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1
Simpson, A. "On flexure-torsion flutter criteria." Aeronautical Journal 103, no. 1028 (October 1999): 457–74. http://dx.doi.org/10.1017/s0001924000064411.
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Abstract The classical criteria of the 1920s for the avoidance of flexure-torsion flutter were based on parameters such as stiffness ratio and the position across the typical chord of the aerodynamic, elastic and mass centres. In more recent times, and in the context of aeroelastic tailoring of lifting surfaces constructed with composite materials, a new terminology has emerged — as evident from technical papers produced in the USA over the past decade. The prevention of flexure-torsion flutter, or the raising of the critical speed, is now achieved by providing more wash-in or less wash-out , where these terms do not have their established aeronautical meanings — and for this reason (and other, non-semantic ones) are to be deprecated. By recourse to a typical section model (with quasi-steady and unsteady compressible aerodynamics), the writer argues that, for conventionally constructed wings, the new criteria are ‘fuzzy’ and incomplete versions of the earlier criteria in respect of the positioning of the various ‘centres’ (i.e., elastic, mass and aerodynamic) across the typical chord, and therefore that the new terminology is redundant in this context. For laminated composite wing structures, even when the construction is uniform and the fiexural axis straight, it is established that the inclination of this axis with respect to the CG and aerodynamic axes may be so large that the fiexural and shear centres at the tip could be several chords forward or aft of the mid-chord axis; the criteria of the 1920s are then irrelevant. The wash-in/wash-out criteria may then be said to ‘come into their own’, albeit that it is shown herein that they remain fuzzy and incomplete — even for quasisteady binary problems. A crude modal binary model of a rudimentary laminated composite wing is included to illustrate this and other features. By recourse to a higher-order flutter formulation, the writer demonstrates that the wash-in/wash-out criteria are, in certain respects, unreliable.
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KIRCHNER, H. P., and J. C. CONWAY. "Criteria for Crack Branching in Cylindrical Rods: II, Flexure." Journal of the American Ceramic Society 70, no. 6 (June 1987): 419–25. http://dx.doi.org/10.1111/j.1151-2916.1987.tb05662.x.
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Grammatikou, Sofia, Dionysis Biskinis, and Michael N. Fardis. "Ultimate Strain Criteria for RC Members in Monotonic or Cyclic Flexure." Journal of Structural Engineering 142, no. 9 (September 2016): 04016046. http://dx.doi.org/10.1061/(asce)st.1943-541x.0001501.
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Nowakowski, Michał, Piotr Małczak, Magdalena Mizera, Mateusz Rubinkiewicz, Anna Lasek, Mateusz Wierdak, Piotr Major, Andrzej Budzyński, and Michał Pędziwiatr. "The Safety of Selective Use of Splenic Flexure Mobilization in Sigmoid and Rectal Resections—Systematic Review and Meta-Analysis." Journal of Clinical Medicine 7, no. 11 (October 27, 2018): 392. http://dx.doi.org/10.3390/jcm7110392.
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Background: According to traditional textbooks on surgery, splenic flexure mobilization is suggested as a mandatory part of open rectal resection. However, its use in minimally invasive access seems to be limited. This stage of the procedure is considered difficult in the laparoscopic approach. The aim of this study was to systematically review literature on flexure mobilization and perform meta-analysis. Methods: A systematic review of the literature was performed using the Medline, Embase and Scopus databases to identify all eligible studies that compared patients undergoing rectal or sigmoid resection with or without splenic flexure mobilization. Inclusion criteria: (1) comparison of groups of patients with and without mobilization and (2) reports on overall morbidity, anastomotic leakage, operative time, length of specimen, number of harvested lymph nodes, or length of hospital stay. The outcomes of interest were: operative time, conversion rate, number of lymph nodes harvested, overall morbidity, mortality, leakage rate, reoperation rate, and length of stay. Results: Initial search yielded 2282 studies. In the end, we included 10 studies in the meta-analysis. Splenic flexure is associated with longer operative time (95% confidence interval (CI) 23.61–41.25; p < 0.001) and higher rate of anastomotic leakage (risk ratios (RR): 1.02; 95% CI 1.10–3.35; p = 0.02), however the length of hospital stay is shorter by 0.42 days. There were no differences in remaining outcomes. Conclusions: Not mobilizing the splenic flexure results in a significantly shorter operative time and a longer length of stay. Further research is required to establish whether flexure mobilization is required in minimally invasive surgery.
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Bai, J. B., R. A. Shenoi, X. Y. Yun, and J. J. Xiong. "Progressive damage modelling of hybrid RTM-made composite Π-joint under four-point flexure using mixed failure criteria." Composite Structures 159 (January 2017): 327–34. http://dx.doi.org/10.1016/j.compstruct.2016.09.083.
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Molina-Cerrillo, Javier, María San Román, Javier Pozas, Teresa Alonso-Gordoa, Miguel Pozas, Elisa Conde, Marta Rosas, Enrique Grande, María Laura García-Bermejo, and Alfredo Carrato. "BRAF Mutated Colorectal Cancer: New Treatment Approaches." Cancers 12, no. 6 (June 14, 2020): 1571. http://dx.doi.org/10.3390/cancers12061571.
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Colon cancer is one of the most frequently diagnosed malignancies in adults, considering both its incidence and prevalence. Anatomically, the right colon is considered as being from the cecum to the splenic flexure, and the left colon is from the splenic flexure to the rectum. Sidedness is a surrogate of a wide spectrum of colorectal cancer (CRC) biology features (embryology, microbiome, methylation, microsatellite instability (MSI), BRAF, aging, KRAS, consensus molecular subtypes (CMS), etc.), which result in prognostic factors. Different molecular subtypes have been identified, according to genomic and transcriptomic criteria. A subgroup harboring a BRAF mutation has been described, and represents approximately 10% of the patients diagnosed with colon cancer. This subgroup has morphological, clinical, and therapeutic characteristics that differ substantially from patients who do not carry this genetic alteration. Unfortunately, there is no established standard of care for this particular cohort of patients. This manuscript aims to study the biology of this subgroup of colon cancer, to understand the current approach in clinical research.
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Kelly, Trevor. "Nonlinear analysis of reinforced concrete shear wall structures." Bulletin of the New Zealand Society for Earthquake Engineering 37, no. 4 (December 31, 2004): 156–80. http://dx.doi.org/10.5459/bnzsee.37.4.156-180.
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Although shear walls are a widely used system for providing lateral load resistance, nonlinear analysis procedures for this type of element are much less well developed than those for frame and truss elements. Equivalent flexural models do not include shear deformation and are only suited for symmetric, straight walls. This paper describes the development of an analysis model which includes nonlinear effects for both shear and flexure. The formulation is based on a "macro" modelling approach which is suitable for complete building models in a design office environment.
An analysis methodology is developed using engineering mechanics and experimental results and implemented in an existing nonlinear analysis computer program. A model is developed and validated against test results of solid walls and walls with openings. This shows that the model can capture the general characteristics of hysteretic response and the maximum strength of the wall. Results can be evaluated using acceptance criteria derived from published guidelines. An example shear wall building is then evaluated using both the nonlinear static and the nonlinear dynamic procedures. The procedure is shown to be a practical method for implementing performance based design procedures for shear wall buildings.
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Lisowski, Bartłomiej. "Impact of Fiber Metal Laminates - Literature Research." Mechanics and Mechanical Engineering 22, no. 4 (September 2, 2020): 1355–70. http://dx.doi.org/10.2478/mme-2018-0106.
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AbstractThe paper refers the general idea of composite materials especially Fiber Metal Laminates (FMLs) with respect to low-velocity impact incidents. This phenomenon was characterized by basic parameters and energy dissipation mechanisms. Further considerations are matched with analytical procedures with reference to linearized spring-mass models, impact characteristics divided into energy correlations (global flexure, delamination, tensile fracture and petaling absorbed energies) and set of motion second order differential equations. Experimental tests were based on analytical solutions for different types of FML - GLARE type plates and were held in accordance to ASTM standards. The structure model reveals plenty of dependences related to strain rate effect, deflection represented by the correlations among plate and intender deformation, separate flexure characteristics for aluminium and composite, contact definition based on intender end-radius shape stress analysis supported by FSDT, von Karman strains as well as CLT. Failure criteria were conformed to layers specifications with respect to von Misses stress-strain criterion for aluminium matched with Tsai-Hill or Puck criterion for unidirectional laminate. At the final stage numerical simulation were made in FEM programs such as ABAQUS and ANSYS. Future prospects were based on the experiments held over 3D-fiberglass (3DFG) FMLs with magnesium alloy layers which covers more favorable mechanical properties than FMLs.
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Schmieder, Annett, Thorsten Heinze, and Markus Michael. " Failure Analysis of High-Strength Fiber Ropes." Materials Science Forum 825-826 (July 2015): 891–98. http://dx.doi.org/10.4028/www.scientific.net/msf.825-826.891.
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Until the present days, in discontinuous conveyor systems, e.g. cranes and elevators, steel wire ropes and steel chains are the exclusively used tension members. Nevertheless, these tension members are exhibiting essential disadvantages, e.g. high dead weight, low bending flexure and high susceptibility to corrosion. For fulfilling the steadily increasing requirements especially in running ropes, alternative tension members have to be developed and approved concerning their series-production readiness by utilization of new technologies and new materials. High-strength fiber ropes are demonstrating promising mechanical properties, regarding tensile strength, vibration behavior and bending fatigue life. Still, the application of such high-strength fiber ropes is limited, due to unavailable systematic investigations and insufficient guidelines for dimensioning and processes for determination of discard criteria. With the help of new technologies and procedures, e.g. multi-zone cyclic bend-over-sheave (CBOS) test machinery and computer-assisted tomography, new knowledge concerning the wear behavior of fiber ropes is to be gained and new discard criteria are to be developed.
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Joseph, Thomas K., K. Renji, and Kartik Venkatraman. "On the Region for the Application of Passive Damping Treatment and Loss Factor Enhancement." International Journal of Acoustics and Vibration 24, no. 4 (December 31, 2019): 693–700. http://dx.doi.org/10.20855/ijav.2019.24.41432.
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The loss factor of a structure is significantly improved by using constrained damping treatment. For a mass efficient design, the damping material is to be applied at suitable locations. The studies reported in literature use the modal strain energy distribution in the viscoelastic material or the strain energy distribution in the base structure as tools to arrive at these suitable locations for the damping treatment. It is shown here that the regions identified through the above criteria need not be suitable for certain bending modes of vibration. A new approach is proposed in which the strain in the viscoelastic material and the angle of flexure are shown to be more reliable in arriving at the locations for the damping treatment. Providing damping layers at identified locations using these parameters results in significant loss factors with minimal added mass.
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Hallad, Shankar A., Nagaraj R. Banapurmath, Arun Y. Patil, Anand M. Hunashyal, and Ashok S. Shettar. "Studies on the effect of multi-walled carbon nanotube–reinforced polymer-based nano-composites using finite element analysis software tool." Proceedings of the Institution of Mechanical Engineers, Part N: Journal of Nanomaterials, Nanoengineering and Nanosystems 230, no. 4 (August 3, 2016): 200–212. http://dx.doi.org/10.1177/1740349915599182.
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This article confirms experimental results by finite element analysis. The study includes meshing the specimen of size 40 × 12 × 6 mm3. The model is constructed in DesignModeler (ANSYS Workbench). Multi-walled carbon nanotubes are aligned in different angles to correlate the experimental results. The modelling method employed for analysis is based on weight ratio. The proportion of multi-walled carbon nanotubes is 0.25%, 0.5%, 0.75% and 1% by weight of polymer matrix (epoxy resin) for different specimens. Multi-walled carbon nanotubes are dispersed in epoxy matrix using ultrasonic energy. Composite beams were tested under flexure in order to evaluate their mechanical property such as load–deflection criteria by three-point bending test. Finite element method results were in close agreement with the experimental outcomes with different orientation of multi-walled carbon nanotubes into the matrix considered.
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Czechowski, Leszek, Wojciech Śmiechowicz, Gabriela Kmita-Fudalej, and Włodzimierz Szewczyk. "Flexural Damage of Honeycomb Paperboard—A Numerical and Experimental Study." Materials 13, no. 11 (June 7, 2020): 2601. http://dx.doi.org/10.3390/ma13112601.
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This paper presents an experimental and numerical analysis using the finite element method (FEM) of the bending of honeycomb-core panel. Segments of honeycomb paperboard of several thicknesses were subjected to four-point flexure tests to determine their bending stiffness and maximum load. Several mechanical properties of orthotropic materials were taken into account to account for the experimental results. The numerical analysis of the damage prediction was conducted by using well-known failure criteria such as maximum stress, maximum strain and Tsai-Wu. The present study revealed how to model the honeycomb panel to obtain curves close to experimental ones. This approach can be useful for modelling more complex structures made of honeycomb paperboard. Moreover, thanks to the use of variously shaped cells in numerical models, i.e., the shape of a regular hexagon and models with a real shape of the core cell, results of the calculation were comparable with the results of the measurements. It turned out that the increase of maximum loads and rise in stiffness for studied samples were almost either linearly proportional or quadratically proportional as a function of the panel thickness, respectively. On the basis of failure criteria, slightly lower maximum loads were attained in a comparison to empiric maximum loads.
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Mansouri, Lilla, Arezki Djebbar, Samir Khatir, Hafiz Tauqeer Ali, Amar Behtani, and Magd Abdel Wahab. "Static and fatigue behaviors of short glass fiber–reinforced polypropylene composites aged in a wet environment." Journal of Composite Materials 53, no. 25 (July 11, 2019): 3629–47. http://dx.doi.org/10.1177/0021998319861142.
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In this paper, a new experimental study of the bending static and fatigue behaviors of a composite material reinforced with 40% by mass of short glass fibers (type E) and polypropylene matrix is presented. The composite material is obtained in the form of plates by an injection process, which inevitably affects the distribution of the fibers and therefore the behavior of the material studied. To do this, several techniques are implemented on specimens by cutting them in transverse and longitudinal directions. The effect of aging in distilled water at 40℃ on the mechanical characteristics is studied under static and fatigue loading conditions. The static tests, three-point flexure up to failure, allow us to choose the levels of stress for the fatigue tests. The endurance curves as a function of the number of cycles are plotted by adapting the end-of-test criteria N5, N10, and N20, which represent a rigidity drop of 5%, 10%, and 20%, respectively. An interpretation of the Wöhler curve equations defined for the end-of-test criteria allows defining the kinetics of material damage. The results highlighted the influence of distilled water on the mechanical behavior and the lifetime of the material. We also perform macroscopic observations of fracture and microscopic facies in order to identify the damage mechanisms of the composite material.
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Muzaffar, Mahvish, and Abdul Rafeh Naqash. "Synchronous brain metastasis and impact of primary tumor side in colorectal cancers." Journal of Clinical Oncology 37, no. 4_suppl (February 1, 2019): 712. http://dx.doi.org/10.1200/jco.2019.37.4_suppl.712.
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712 Background: 25% of patients with colorectal cancer(CRC) present with synchronous metastatic disease. The incidence of brain metastasis (BM) in CRC is very low (1.2–3.2%) and tend to occur later in the disease course. Synchronous BM(SBM) in CRC is very rare. We sought to explore the impact of primary tumor characteristics on SBM. Methods: Surveillance Epidemiology End Results Program (SEER) 18 registries research data on primary colorectal cancer cases diagnosed during 2010-2015 with brain metastasis at diagnosis were identified. Patients with unlabeled primary site and autopsy alone cases were excluded. Demographic and colorectal cancer characteristics including age, gender, race, tumor grade and primary tumor side were analyzed. Logistic regression model was used to test the association between survival and side of cancer. Results: A total of 475 cases met the inclusion criteria. The mean age was 64.04 yrs. (range 28-95). Majority of the patients (80%) were white, 12% black and others (8%), Male: Female ratio was 1:1.58% patients had primary tumor on left side (splenic flexure, sigmoid, rectosigmoid and rectal) and 42% had right sided (ascending colon, hepatic flexure, cecum, transverse colon) primary tumor. The median overall survival was 5 months with 1-year survival of 26% in the whole cohort. The 1-year overall survival was 21% for patients with right sided primary tumor versus 30% for patients with SBM and left sided primary tumor(p = 0.03). The median disease specific survival was 5 months for right side and 7 months for Left sided tumor with SBM. The regression model showed that higher grade (RR 14, p = 0.003)) and right sided primary tumor (RR 4.2, p = 0.04) were associated with worse outcome among patients with SBM in colorectal cancer. Conclusions: Synchronous brain metastasis is very rare in colorectal cancer. Tumor side seems to be prognostic even in this aggressive disease subset. This differential outcome further indicates that sidedness should be considered in goals of care and treatment discussion.
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Nessim, Maher A., Han Ping Hong, and James G. MacGregor. "Verification of the material resistance factors in the CSA-S474 code for offshore concrete structures." Canadian Journal of Civil Engineering 20, no. 4 (August 1, 1993): 660–71. http://dx.doi.org/10.1139/l93-083.
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The Canadian Standards Association has developed a national code for the design, construction and installation of fixed offshore structures. This code was developed on the basis of probabilistic principles. It consists of five parts (CAN/CSA-S471 to S475), dealing with general loading and design requirements, foundations, steel structures, concrete structures, and sea operations. The material resistance factors cited in the part on concrete structures (S474-M1989) were verified using data typical of offshore structures for a set of representative design cases. The test cases were based on reinforced concrete ice resisting walls with configurations typical of those contemplated for offshore structures in Canada. They covered rare and frequent ice loading for safety classes I and II under flexure, combined flexure and axial force, and shear. The test cases were designed according to the CSA and DnV code provisions, and the reliabilities associated with the resulting members were calculated and assessed. The results indicate that the reliabilities achieved by designing to the CSA standard for safety class I sections are greater than those obtained by designing to DnV rules for all cases considered. Designs carried out according to CSA-S474 meet the target reliabilities implied by CSA-S471 for values of the coefficient of variation of the in situ concrete strength of up to 12% and are, in many cases, very conservative. Sensitivity analysis of safety class I members suggests that the material resistance factors can be increased. Issues that need to be addressed in order to justify an increase in the factors include the acquisition of more data on in situ concrete strength and a more comprehensive consideration of the design conditions covered by the code. The overall consistency of the reliability levels associated with the CSA code can be improved by simultaneous verification of the material factors in CSA-S474 and the load criteria and factors in CSA-S471. Key words: concrete structures, offshore structures, code verification, structural reliability, in situ concrete strength.
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Yoon, Soon Jong, Jae Ho Jung, and Won Sup Jang. "Elastic Web Buckling Strength of Pultruded Flexural Members." Key Engineering Materials 261-263 (April 2004): 621–26. http://dx.doi.org/10.4028/www.scientific.net/kem.261-263.621.
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This paper presents the analytical investigations pertaining to the elastic buckling behavior of orthotropic composite plates. By the pultrusion process the structural shapes composed of orthotropic plate components are readily available in the construction market. When the member is utilized for the flexure, lateral-torsional buckling and local buckling behaviors must be taken into consideration. In the local buckling analysis, flange and web local buckling analyses must be conducted in the design of such a member. For finding the web buckling strength, the buckling equation for the orthotropic plate under linearly distributed in-plane forces is derived by using the Rayleigh-Ritz method. The boundary conditions of plate are assumed that the loaded edges are simply supported and the unloaded edges are simply supported or fixedly supported. The buckling coefficient of a plate having different orthogonal mechanical properties is found by using the numerical technique and the minimum buckling coefficient is suggested. In addition, simplified form of equation for predicting the minimum buckling coefficient for the plate is proposed. Brief discussion on the design criteria relating to the web local buckling is also provided.
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Bertario, Lucio, Hugo Aste, Arrigo Arrigoni, Pierluigi Fracasso, Francesco Paolo Rossini, Carlo Rossetti, and Rosa Valanzano. "Clinical Aspects and Management of Hereditary Non-Polyposis Colorectal Cancer (HNPCC)." Tumori Journal 82, no. 2 (March 1996): 117–21. http://dx.doi.org/10.1177/030089169608200205.
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Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomical dominant trasmitted disease phenotypically defined according to the “Amsterdam criteria” as follows: at least 3 affected relatives, one of whom first degree relative of other two, at least two successive generations affected. Important cardinal features are: 1 prevalent proximal location of cancers (above splenic flexure); 2 multiple synchronous or methachronous large bowel cancers; 3 early age of onset (<50 years); 4 presence of extracolonic cancers (endometrium, stomach, urinary tract, skin). The treatment is essentially surgical and total colectomy with ileo-rectum anastomosis is already proposed as standard procedure with annual endoscopic examination of retained rectum. The screening of individuals at risk, so determined by the analysis of pedigree or the results of molecular tests, must be performed every 1-2 years by colonoscopy starting around the age of 25 years. In this review are described and analysed the spectrum of the disease with particular attention to the frequency and characteristics of extracolonic cancers. Moreover, the guidelines of the surveillance and screening are reported following the data of the literature and as proposed by the International Collaborative Group (ICG-HNPCC).
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Jung, Woo-tai, Jong-sup Park, Jae-yoon Kang, and Moon-seoung Keum. "Flexural Behavior of Concrete Beam Strengthened by Near-Surface Mounted CFRP Reinforcement Using Equivalent Section Model." Advances in Materials Science and Engineering 2017 (2017): 1–16. http://dx.doi.org/10.1155/2017/9180624.
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FRP (fiber reinforced polymer) has found wide applications as an alternative to steel rebar not only for the repair and strengthening of existing structures but also for the erection of new structures. Near-surface mounted (NSM) strengthening was introduced as an alternative of externally bonded reinforcement (EBR) but this method also experiences early bond failure, which stresses the importance of predicting accurately the bond failure behavior in order to evaluate precisely the performance of NSM reinforcement. This study proposes the equivalent section model assuming monolithic behavior of the filler and CFRP reinforcement. This equivalent section model enables establishing a bond failure model applicable independently of the sectional shape of the CFRP reinforcement. This so-derived bond failure model is then validated experimentally by means of beams flexure-strengthened by NSM CFRP reinforcements with various cross-sections. Finally, analytical analysis applying the bond failure model considering the equivalent section and defined failure criteria is performed. The results show the accuracy of the prediction of the failure mode as well as the accurate prediction of the experimental results regardless of the sectional shape of the CFRP reinforcement.
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Campilho, Raul D. S. G., Marcelo F. S. F. de Moura, A. M. G. Pinto, Dimitra A. Ramantani, J. J. L. Morais, and J. J. M. S. Domingues. "Strength Prediction of Adhesively-Bonded Scarf Repairs in Composite Structures under Bending." Materials Science Forum 636-637 (January 2010): 233–38. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.233.
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This work reports on the experimental and numerical study of the bending behaviour of two-dimensional adhesively-bonded scarf repairs of carbon-epoxy laminates, bonded with the ductile adhesive Araldite 2015®. Scarf angles varying from 2 to 45º were tested. The experimental work performed was used to validate a numerical Finite Element analysis using ABAQUS® and a methodology developed by the authors to predict the strength of bonded assemblies. This methodology consists on replacing the adhesive layer by cohesive elements, including mixed-mode criteria to deal with the mixed-mode behaviour usually observed in structures. Trapezoidal laws in pure modes I and II were used to account for the ductility of the adhesive used. The cohesive laws in pure modes I and II were determined with Double Cantilever Beam and End-Notched Flexure tests, respectively, using an inverse method. Since in the experiments interlaminar and transverse intralaminar failures of the carbon-epoxy components also occurred in some regions, cohesive laws to simulate these failure modes were also obtained experimentally with a similar procedure. A good correlation with the experiments was found on the elastic stiffness, maximum load and failure mode of the repairs, showing that this methodology simulates accurately the mechanical behaviour of bonded assemblies.
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Hu, Yong, Paul M. Jones, and Kangjie Li. "Air Bearing Dynamics of Sub-Ambient Pressure Sliders During Dynamic Unload." Journal of Tribology 121, no. 3 (July 1, 1999): 553–59. http://dx.doi.org/10.1115/1.2834103.
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The increasing effort to use sub-ambient pressure air bearing sliders for dynamic load/unload applications in magnetic hard disk drives requires desirable air bearing characteristics during the dynamic unload event. This paper establishes air bearing design criteria for achieving a smooth head unload performance, through a correlation study between the modeled unloading air bearing dynamics of two 30 percent proximity recording sub-ambient pressure sliders and motion sequence of the same sliders by a high-speed video camera. It is shown that the air bearing lifting force quickly responds to changes in fly height and pitch, while the suction force is relatively resistant to changes in fly height, but somewhat more sensitive to changes in pitch. This unique distinction results in different decreasing rates between the air bearing lifting and suction forces during the unload process, creating a strong dependence of the unloading characteristics on the location of the suction cavities. Both the modeled unloading air bearing dynamics and experimentally recorded motion sequence illustrate that a toward-trailing-edge located suction force acts to pitch the slider up, while the moment produced by a toward-leading-edge located suction force induces a negative pitch motion, resulting in an excessive flexure deformation and dimple separation. Therefore, placing the suction cavities towards the trailing edge offers a reliable unloading performance for the sub-ambient pressure air bearing sliders.
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Zahari, Asril, and Sudiyatmo Sudiyatmo. "HEREDITARY NON-POLYPOSIS COLORECTAL CANCER (LYNCH SYNDROME) PADA WANITA UMUR 16 TAHUN." Majalah Kedokteran Andalas 35, no. 2 (August 29, 2011): 172. http://dx.doi.org/10.22338/mka.v35.i2.p172-180.2011.
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AbstrakKanker kolorektal menduduki peringkat ketiga jenis kanker yang paling sering terjadi di dunia. Sekitar 3% kasus kanker kolorektal merupakan jenis hereditary non polyposis colorectal cancer (HNPCC)/Lynch syndrome, yang sering muncul pada usia muda. Dilaporkan satu kasus di rumah sakit Dr. M. Djamil Padang, wanita berumur 16 tahun dengan keluhan nyeri perut kanan bawah. Didapatkan riwayat penyakit serupa pada kakek, bibi pasien dan enam anggota keluarga yang lain. Pada pemeriksaan fisik abdomen teraba massa dengan konsistensi keras dan terfiksir. Pada kolonoskopi dan biopsi ditemukan tumor jenis adenocarcinoma colon moderatly differentiated di fleksura hepatika dan polip di kolon sigmoid. Berdasarkan kriteria Amsterdam pasien didiagnosa Lynch syndrome. Pada Pasien dilakukan subtotal kolektomi, anastomose ileorectal dan kemoterapi ajuvan. Identifikasi genetik sedang dikerjakan untuk melihat adanya kelainan genetik pada pasien. Pasien melakukan skrining berkala untuk mencegah kanker HNPCC jenis yang lain.Kata kunci : Hereditary non polyposis colorectal cancer, Lynch syndrome, Microsatellite instability, skrining.AbstractCarcinoma colorectal is the third most common type of cancer that occurs in the world. About 2% -3% of cases of colorectal cancer is hereditary non-polyposis colorectal cancer (HNPCC)/Lynch syndrome, which often appear at a young age. Amsterdam and Bethesda criteria have been used to identify patients with Lynch syndrome.one case was reported at the Dr. M. Djamil Padang hospital, a 16-year-old girl with right lower abdominal pain. Obtained a history of similar disease in grandparents, aunts and six other family members. On physical examination found palpable fixed abdominal mass with hard consistency in the lower right abdomen. At colonoscopy and biopsy found a moderatly differentiated adenocarcinoma colon type at the hepatic flexure and the sigmoid colon polyp. Based on the Amsterdam criteria, patients diagnosed with HNPCC/Lynch syndrome. Patients treated with subtotal colectomy, ileorectal anastomose and adjuvant chemotherapy.LAPORAN KASUS173Genetic identification is underway to see any genetic abnormalities. Patients be screened regularly to prevent other types of cancer HNPCC.Key word : Hereditary non-polyposis colorectal cancer, Lynch syndrome, Microsatellite instability, screening.
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Morales-Conde, Salvador, Isaias Alarcón, Tao Yang, Eugenio Licardie, and Andrea Balla. "A Decalogue to Avoid Routine Ileostomy in Selected Patients With Border Line Risk to Develop Anastomotic Leakage After Minimally Invasive Low-Anterior Resection: A Pilot Study." Surgical Innovation 27, no. 1 (December 1, 2019): 44–53. http://dx.doi.org/10.1177/1553350619890720.
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Purpose. Protective ileostomy (PI) during anterior resection (AR) for rectal cancer decreases the incidence of anastomotic leakage (AL) and its subsequent complications, but it may itself be the cause of morbidity. The aim is to report our protocol in the management of selected patients with borderline risk to develop AL after laparoscopic AR and ghost ileostomy (GI) creation. Methods. Patients who underwent AR were stratified based on the risk to develop AL. Steps to avoid PI were splenic flexure mobilization, reduced pelvic bleeding, to employ different stapler charge if neoadjuvant chemo-radiotherapy is performed, to perform a horizontal section of the rectum, to evaluate the anastomotic vascularization with a fluorescence angiography, to perform a side-to-end anastomosis, intraoperative methylene blue test, pelvic and transanal drainage tubes placement, and the GI creation. After surgery, inflammatory blood markers were monitored to detect potential leakages. Results. Twelve patients were included. In one case, the specimen proximal section was changed after fluorescence angiography. There were no conversions in this group of patients. One postoperative AL occurred and was treated with radiological drainage placement, not being necessary to convert the GI. PI was avoided in 100% of cases. Conclusions. Patients’ characteristics cannot be changed, but several steps were used to avoid routine PI creation. The present protocol could be a valuable option to avoid PI in selected patients. Further studies with a wider sample size, and defined criteria to stratify the patients based on the risk to develop AL, are required.
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Aggarwal, Himani, Kristin M. Sheffield, Li Li, David Lenis, Rachael Sorg, and Rebecca Miksad. "HSR19-077: Primary Tumor Location (PTL) and Survival Outcomes in a Real World Cohort of KRAS Wild-Type (WT) Metastatic Colorectal Cancer (mCRC) Patients in the United States." Journal of the National Comprehensive Cancer Network 17, no. 3.5 (March 8, 2019): HSR19–077. http://dx.doi.org/10.6004/jnccn.2018.7164.
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Background: PTL is a prognostic factor for mCRC. Recent data suggest PTL is also predictive of survival benefit with cetuximab (CET) and bevacizumab (BEV). This study evaluated the prognostic and predictive effect of PTL in patients with KRAS WT mCRC who initiated first-line (1L) therapy with CET vs BEV in the real world. Methods: This retrospective study selected patients with KRAS WT mCRC who initiated 1L therapy with CET or BEV + FOLFIRI or FOLFOX between January 2013 and April 2017 from Flatiron Health’s electronic health record-derived database. PTL was abstracted from patients’ charts. Left-sided PTL (LPTL): splenic flexure to rectum; right-sided PTL (RPTL): cecum to splenic flexure. Propensity score matching was used to balance treatment cohorts on baseline characteristics. Kaplan Meier and Cox regression methods were used for survival analyses. Results: 1,312 patients met the selection criteria. Of 248 CET + FOLFIRI or FOLFOX patients, 164 had LPTL and 84 had RPTL; of 1,064 BEV + FOLFIRI or FOLFOX patients, 679 had LPTL and 385 had RPTL. CET LPTL and RPTL patients were more likely to receive FOLFIRI vs BEV patients (LPTL: 64.0% vs 24.3%; P<.001; RPTL: 76.2% vs 24.9%; P<.001). Stage at initial diagnosis was different between CET RPTL vs BEV RPTL patients (P<.001). CET RPTL patients were more likely to be stage III (44.0% vs 22.6%) while BEV RPTL patients were more likely to be stage IV (48.8% vs 65.7%) at initial diagnosis. CET RPTL patients were more likely to have a history of adjuvant chemotherapy vs BEV RPTL patients (47.6% vs 22.3%; P<.001). In the matched sample, median overall survival (OS) was 29.7 months (95% CI, 26.9–35.2) for LPTL patients vs 18.3 months (95% CI, 15.8–21.3) for RPTL patients (P<.001). Median OS was 29.7 months (95% CI, 27.4–NA) for CET LPTL vs 29.1 months (95% CI, 26.6–35.6) for BEV LPTL patients (HR, 0.87; 95% CI, 0.63–1.19; P=.378), and 17.0 months (95% CI, 12.0–32.6) for CET RPTL vs 18.8 months (95% CI, 15.8–22.3) for BEV RPTL patients (HR, 1.00; 95% CI, 0.68–1.46; P=.996). The interaction of treatment and PTL was not significant in the Cox regression. Conclusions: This study found a prognostic effect of PTL but not a predictive effect. LPTL patients had significantly longer OS vs RPTL patients. However, the treatment effect for CET vs BEV by PTL was not significantly different. Future research is needed to examine differences between real-world and clinical trial populations that may have contributed to divergent results.
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Mohammadi, Sajjad, Abd-ol-Reza Sarvghad Moghaddam, and Alireza Faroughi. "The effect of number and position of braced frames on column behavior of the dual steel structural system (MRF and EBF) (With a view on amplified seismic load)." Ciência e Natura 37 (December 21, 2015): 277. http://dx.doi.org/10.5902/2179460x20858.
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In seismic design of structures, determination of number and position of braced frames, considering the architectural scheme of projects, is usually confronted by obstacles. Due to this fact, in some cases, selecting the best location and number of braced bays has led to mistakes in determination of their adjacent members (columns) design loads. One of the seismic design requirements of lateral resisting system is to control the columns adjacent to braced bays for load combinations of amplified seismic load, which is a function of over-strength factor of the structure. This research aims to present and introduce the best structural model of number and position of braced frames in a structural system, such as steel moment resisting frame and eccentric braces dual system; because in 3rd revision of Iranian 2800 standard of seismic provision, there are statements and criteria provided only for capacity of moment frame, not for braces. Though the amplified seismic load function is controlled in models which columns are connected to braces in 2 directions, and seismic loads are applied in those 2 directions, number of damage hinges (Exceeding CP) is significantly increased in comparison to the models with straggly braces. As the increase in axial force of these columns leads to decrease in their moment capacity (despite controlling the amplified seismic load provision), columns in dual systems that resist flexure, would be damaged and exceed the collapse threshold much sooner than other columns. This important fact is not presented in Iranian or even American codes and provisions.
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Cheung, Ka-Shing, Lijia Chen, Esther W. Chan, Wai-Kay Seto, Ian C. K. Wong, and Wai K. Leung. "Statins reduce the progression of non-advanced adenomas to colorectal cancer: a postcolonoscopy study in 187 897 patients." Gut 68, no. 11 (February 26, 2019): 1979–85. http://dx.doi.org/10.1136/gutjnl-2018-317714.
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Background and aimsPostcolonoscopy colorectal cancer (PCCRC) accounts for up to 9% of all CRCs. Statins have been shown to be associated with a lower CRC risk. We aimed to investigate whether PCCRC risk was also lower among statin users.MethodsThis is a retrospective cohort study using a territory-wide electronic healthcare database in Hong Kong including patients aged 40 years or above who had undergone colonoscopies between 2005 and 2013. Exclusion criteria included prior colorectal cancer (CRC), inflammatory bowel disease, prior colectomy and CRC detected within 6 months of index colonoscopy. We defined statin use as at least 90-day use before index colonoscopy. Medication use was traced up to 5 years before index colonoscopy. PCCRC-3y was defined as cancer diagnosed between 6 and 36 months after index colonoscopy. Sites of CRC were categorised as proximal (proximal to splenic flexure) and distal cancer. The subdistribution HR (SHR) of PCCRC-3y with statin use was derived by propensity score matching based on covariates (including patient factors, concurrent medication use and endoscopy centre’s performance).ResultsOf 187 897 eligible subjects, 854 (0.45%) were diagnosed with PCCRC-3y. Statin use was associated with a lower PCCRC-3y risk (SHR: 0.72; 95% CI 0.55 to 0.95; p=0.018). Subgroup analysis shows that SHRs were 0.50 (95% CI 0.28 to 0.91; p=0.022) for proximal and 0.80 (95% CI 0.59 to 1.09; p=0.160) for distal cancer. Older (>60 years) patients, women and those without diabetes mellitus or polyps appeared to benefit more from statins.ConclusionsStatins were associated with a lower PCCRC risk, particularly for proximal cancer.
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Cheung, Ka Shing, Esther W. Chan, Wai Kay Seto, Ian C. K. Wong, and Wai K. Leung. "ACE (Angiotensin-Converting Enzyme) Inhibitors/Angiotensin Receptor Blockers Are Associated With Lower Colorectal Cancer Risk." Hypertension 76, no. 3 (September 2020): 968–75. http://dx.doi.org/10.1161/hypertensionaha.120.15317.
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Whether ACE (angiotensin-converting enzyme) inhibitors and angiotensin receptor blockers modify colorectal cancer risk remains controversial. We aimed to determine association between their use and colorectal cancer risk after a negative baseline colonoscopy. This is a territory-wide retrospective cohort study recruiting patients aged ≥40 who had undergone colonoscopy between 2005 and 2013. Exclusion criteria included colorectal cancer detected <6 months of index colonoscopy, prior colorectal cancer, inflammatory bowel disease, and prior colectomy. The primary outcome was colorectal cancer diagnosed between 6 and 36 months after index colonoscopy. Sites of colorectal cancer were categorized as proximal (proximal to splenic flexure) and distal cancer. The adjusted hazard ratio of colorectal cancer with ACE inhibitor/angiotensin receptor blocker use (≥180-day use within 5 years before index colonoscopy) was derived by propensity score regression adjustment of 23 covariates (including patient’s factors, concurrent medication use, and endoscopy center’s performance). Of 187 897 eligible patients, 30 856 (16.4%) were ACE inhibitors/angiotensin receptor blocker users. Eight hundred fifty-four (0.45%) developed colorectal cancer between 6 and 36 months after index colonoscopy (proximal cancer: 147 [17.2%]). These drugs were associated with lower risk of colorectal cancer that developed <3 years after index colonoscopy (adjusted hazard ratio, 0.78 [95% CI, 0.64–0.96]), but not colorectal cancer that developed >3years (adjusted hazard ratio, 1.18 [95% CI, 0.88–1.57]); every single year increase in the drug use was associated with 5% reduction in adjusted hazard ratio risk. ACE inhibitors/angiotensin receptor blocker were associated with a lower colorectal cancer risk in a duration-response manner.
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Gowarty, Jasmine Lizette, Charis Durham, Lucas Wong, and Wencong Chen. "Survival outcomes of left-sided versus right-sided colon cancer." Journal of Clinical Oncology 37, no. 4_suppl (February 1, 2019): 502. http://dx.doi.org/10.1200/jco.2019.37.4_suppl.502.
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502 Background: Right-sided colon cancers (RCC) are defined up to the splenic flexure where as left-sided colon cancers (LCC) involve the descending, sigmoid, and rectosigmoid regions. The landmark CALGB/SWOG 80405 study concluded that sidedness was an independent prognostic factor for survival in stage IV adenocarcinoma of the colon or rectum, with a poorer prognosis in RCC. This raises the question as to whether or not stage of malignancy plays a role. We performed a retrospective analysis on survival for stage I to IV colon cancer treated at our institution in order to assess if tumor location is an independent prognostic factor as described in previous studies. Methods: Primary site of cancer, sex, age at diagnosis, vital status, and year of diagnosis for stage I, II, III, and IV colon cancer was collected from our institution’s tumor registry from 2007 to 2017. The inclusion criteria included those diagnosed with stage I to IV colon cancer at 18 years of age and above. Exclusion criteria included a diagnosis of both RCC and LCC and patients under age 18. The median of overall survival and time to recurrence between LCC and RCC were compared using Wilcoxon Rank Sum Test with two-sided significance level at 0.05. Results: Time to overall survival and time to recurrence was shown to have no significant difference between RCC and LCC (p = 0.3398 and 0.9467, respectively). Cox proportional hazards model adjusted for age and sex also support the claim (p = 0.1725 and 0.0633). There was a statistically significant difference in age between the two groups with the older mean age seen in RCC (68 versus 62). The distribution of recurrence was statistically significant with a higher recurrence in RCC (p = 0.0105). Conclusions: Unlike CALGB/SWOG 80405, our analysis included the transverse colon as part of RCC and examined stage I to IV colon cancer to ultimately conclude that there was no significant difference in overall survival or time to recurrence. Our study suggests that tumor location is not an independent prognostic factor on survival for all stages of colon cancer. However, a higher suspicion for recurrence may be needed for those diagnosed with RCC. Future investigations involving molecular subtypes and mutations are needed to further clarify prognosis and tumor sidedness.
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Wang, Xiao-Tong, Lei Li, Fan-Biao Kong, Xiao-Gang Zhong, and Wei Mai. "Surgical-related risk factors associated with anastomotic leakage after resection for rectal cancer: a meta-analysis." Japanese Journal of Clinical Oncology 50, no. 1 (October 30, 2019): 20–28. http://dx.doi.org/10.1093/jjco/hyz139.
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Abstract Objectives Anastomotic leakage (AL) after anterior resection always leads to longer hospital stays, decreased quality of life and even increased mortality. Despite extensive research, no consensus on the world well-concerned surgical-related risk factors exists. We therefore conducted a meta-analysis of the available published literature to identify the effects of surgical-related risk factors for AL after anterior resection for rectal cancer, hoping to provide more information and improved guidance for clinical workers managing patients with rectal cancer who are at a high risk for AL. Methods In this study, the relevant articles were systematically searched from EMBASE, MEDLINE, PubMed, WangFang (Database of Chinese Ministry of Science & Technology), Chinese National Knowledge Infrastructure Database and China Biological Medicine Database. The pooled odds ratio (OR) with 95% confidence interval (95% CI) were calculated. Meta-analysis was performed using of RevMan 5.3 software. Results A total of 26 studies met the inclusion criteria and comprised 34238 cases. Analysis of these 26 studies showed that no defunctioning stoma was highly correlated with AL (pooled OR = 1.28, 95%CI: 1.05–1.57, P = 0.01, random effect), and intraoperative blood transfusion was significantly associated with AL (pooled OR = 1.64, 95%CI: 1.34–2.02, P = 0.02, random effect). However, the AL was not associated with type of anastomosis, type of surgery, technique of anastomosis, level of inferior mesenteric artery ligation, operation time and splenic flexure mobilization. Conclusions Depend on this meta-analysis, no defunctioning stoma and intraoperative blood transfusion are the major surgical-related risk factors for AL after resection for rectal cancer. Because of the inherent limitations of the research, future prospective randomized controlled trials will need to confirm this conclusion.
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Chen, Gong, Feng Wang, Weiwei Xiao, Ying Jin, Rong-Xin Zhang, Peiqiang Cai, Min Liu, et al. "Pd1 antibody sintilimab for dMMR/MSI-H locally advanced rectal cancer: An open-label, phase 2, single-arm study (cohort A)." Journal of Clinical Oncology 39, no. 15_suppl (May 20, 2021): e15602-e15602. http://dx.doi.org/10.1200/jco.2021.39.15_suppl.e15602.
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e15602 Background: Immunotherapy has shown satisfactory effect for dMMR/MSI-H colorectal cancer patients. Whether Pd-1 antibody would bring benefit for dMMR/MSI-H locally advanced rectal cancer (LARC) patients in neoadjuvant setting is worthy of investigation. This is a clinical trial with two cohorts according the MMR/MSI status(clinicalTrials.gov, NCT04304209). Methods: LARC patients with dMMR or MSI-H tumor will enter Cohort A and receive neoadjuvant Pd1 antibody sintilimab for four cycles and subsequent surgery or watch and wait, followed by adjuvant four cycles of Pd1 antibody sintilimab with or without chemotherapy. Main inclusion criteria include: cT3-4N0M0 or cTxN+M0 rectal adenocarcinoma, dMMR/MSI-H confirmed by immunohistochemistry (IHC) or gene test, aged 18-75y; ECOG performance 0-1; no previous anti-tumor treatment for rectal adenocarcinoma. Primary outcome is pathologic complete response (pCR) rate. We use a Simon two-stage optimum design to test the null hypothesis of a 15% pCR rate, the historical response rate to standard neoadjuvant chemoradiotherapy (NACRT), against the desired alternative of 30% pCR rate. This had a one-sided type I error of 5% and a power of 80%. In the first stage of this design, 19 patients will be accrued. If 3 or fewer pCR was observed, the study was to be terminated and declared negative. If the trial goes on to the second stage, a total of 55 patients will be studied. The study was deemed to have met its primary endpoint if confirmed pCR were observed in 13 or more patients. Considering 10% dropout rate, a total of 61 patients will be enrolled. Whole exome sequencing, bulk RNA sequencing, single cell RNA sequencing and IHC of the rectal primary tumor are planned. The study started in October, 2019. Results: Eight patients have been enrolled and six have response evaluation results. Four patients achieved clinical complete response (cCR) after 4 cycles of neoadjuvant Pd1 antibody sintilimab treatment and three of them enter watch and wait strategy and finished the adjuvant 4 cycles of Pd1 antibody sintilimab treatment. The 4th patient was diagnosed as lynch syndrome, but molecular test was not feasible for the tumors located at the sigmoid and hepatic flexure because of ileus. He received subtotal colectomy and tumors at the sigmoid and hepatic flexure also achieved pCR. The 5th patient has partial response after 4 and 8 cycles of sintilimab treatment, and then received Dixon surgery and pathology showed major reponse (5% cancer cell left only in the mucosal layer, ypTis). The 6th patient has partial response after 4 and 8 cycles of sintilimab treatment, and sintilimab was still continued concerning intact bladder conservation. No grade 3 toxicity was noted yet. Conclusions: Pd1 antibody sintilimab achieved 4CR (pCR+cCR) in 6 dMMR/MSI-H LARC patients with limited toxicities. Pd1 antibody is quite effective and may be an alternative for these patients. Clinical trial information: NCT04304209.
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Schramm, Christoph, Katharina Janhsen, Jan-Hinnerk Hofer, Hans Toermer, Annette Stelzer, Frank Stenschke, Michael Stollenwerk, et al. "Detection of clinically relevant serrated polyps during screening colonoscopy: results from seven cooperating centers within the German colorectal screening program." Endoscopy 50, no. 10 (May 4, 2018): 993–1000. http://dx.doi.org/10.1055/a-0598-4477.
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Abstract Background Serrated polyps have been recognized as precursors of colorectal cancer (CRC) via the serrated pathway. Endoscopic detection and histopathological evaluation of serrated polyps are challenging. The aims of this study were to determine detection rates of the recently proposed entity of clinically relevant serrated polyps (crSPs) and to identify factors that influence their detection in a primary colonoscopy screening cohort. Methods We retrospectively analyzed average-risk screening colonoscopies performed at a tertiary academic hospital and six community-based private practices in Germany between 01/01/2012 and 14/12/2016. Exclusion criteria were age < 50 years, conditions with increased risk for CRC (e. g. inflammatory bowel disease, history of CRC, hereditary cancer syndromes), and incomplete procedures. CrSPs were defined as serrated polyps ≥ 10 mm and/or > 5 mm located proximally to the splenic flexure. Conventional adenomas were defined as adenomas excluding serrated polyps. Results A total of 4161 colonoscopies from average-risk individuals were included (median age 62 years [interquartile range 56 – 69]; 48.6 % male). CrSPs were detected in 6.9 %, with a mean detection rate of 4.7 % (95 % confidence interval 2.3 % – 7.2 %). Detection rates ranged from 0 % to 16.2 %. In multivariate analysis, simultaneous detection of conventional adenomas and an endoscopist adenoma detection rate of ≥ 25 % were significantly associated with increased detection of crSPs, with odds ratios of 1.43 (95 %CI 1.11 – 1.85; P = 0.01) and 7.35 (95 %CI 4.43 – 12.19; P < 0.001). The individual endoscopist’s detection rate for conventional adenomas and crSPs were significantly correlated (r = 0.54, P = 0.02). Conclusion Detection rates for crSPs differed between participating endoscopists. However, individual skills to detect polypoid lesions have a relevant bearing on the detection rate of crSPs.
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Stintzing, Sebastian. "Recent advances in understanding colorectal cancer." F1000Research 7 (September 24, 2018): 1528. http://dx.doi.org/10.12688/f1000research.14604.1.
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The achievements in the treatment of metastatic colorectal cancer during recent years are based on a better understanding of the disease and individualized regimen planning. In adjuvant treatment, the highly important IDEA (International Duration Evaluation of Adjuvant Chemotherapy) study has shown that treatment duration can safely be reduced in selected patient populations. In patients with pN1 and pT1-pT3 tumors, 3 months of treatment with 5-fluorouracil and oxaliplatin is comparable with respect to 3-year survival rate to 6 months of treatment. For patients with N2 tumors, 6 months of treatment should stay the standard of care. The limitation of the duration of the adjuvant treatment is significantly reducing the chemotherapy-induced morbidity. New studies will explore the use of immune-checkpoint inhibitors in the adjuvant setting in microsatellite-instable (MSI) tumors. In metastatic disease, next to the required molecular testing for RAS and BRAF mutations, MSI testing is recommended. In the rare group of patients with a MSI tumor, immune-checkpoint inhibition is changing the course of the disease dramatically. Therefore, it is important to identify those patients early. For the RAS-mutant cases, no new and targeted treatment options have been identified yet. An optimal treatment strategy for those patients is urgently needed. RAS wild-type patients with tumors derived from the left side of the colon (splenic flexure to rectum) should be treated in first line with epithelial growth factor receptor (EGFR) antibodies. This selection by a molecular and a clinical marker increased the benefit derived by EGFR antibodies dramatically and defined the most effective treatment option for those patients. New selection criteria based on gene expression, methylation, and other molecular changes are explored and will further influence our therapeutic strategies in the future.
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Xiao, Zhi-tao, Rong-xin Zhang, Yang Zhao, Jian-Hong Peng, Pei-Rong Ding, Xiao Jun Wu, Zhen-hai LU, et al. "The correlation between mismatch repair status and clinicopathological characteristics in Chinese colorectal cancer patients." Journal of Clinical Oncology 35, no. 4_suppl (February 1, 2017): 544. http://dx.doi.org/10.1200/jco.2017.35.4_suppl.544.
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544 Background: Our study aimed to explore the relationship between mismatch repair (MMR) status and clinicopathological characteristics in Chinese patients with colorectal cancer (CRC). Methods: A total of 2684 patients with histologically confirmed adenocarcinoma of CRC were consecutively recruited between May 2011 and May 2015 at Sun Yat-sen University cancer center. The exclusion criteria included multiple primary tumors, synchronous and metachronous CRC, and familial adenomatous polyposis. The CRC was defined as left colon with the tumor located below the splenic flexure or rectum, otherwise grouped as right colon. Correlations of MMR status and patient’s demographics, tumor characteristics and TNM staging (exclude 315 CRC patients receiving neoadjuvant therapy) were investigated. Results: We found that deficient MMR (dMMR) status was more likely detected in younger CRC patients compared to the the elderly (12.7% vs 7.5%, P < 0.001). The dMMR rate in right colon cancer was significantly higher than that in left colon cancer and rectal cancer (22.7% vs 7.2% vs 5.2%, P < 0.001).With respect to tumor differentiation, we found that the mucinous adenocarcinoma had the highest rate of dMMR(24.4%), followed by poorly differentiated adenocarcinoma(18.5%), signet-ring cell carcinoma(17.6%), well differentiated adenocarcinoma(9.5%), moderately differentiated adenocarcinoma(8.9%), and neuroendocrine carcinoma (0%) ( P < 0.001). In addition, the proportions in stage I, stage II, stage III and stage IV CRC were 9.7%, 16.5% , 8.5% and 3.9%, respectively ( P < 0.001). There was no significant difference in gender (P = 0.114). Conclusions: At the first time, our study demonstrated that dMMR status was most likely detected at younger age (less than 59 years) and stage II right colon mucinous adenocarcinoma in large volume Chinese patients, which was similar to the results in western countries.
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Mishani, Siamak, Brian Evans, Vamegh Rasouli, Reem Roufail, Soren Soe, and Peter Jaensch. "Interlaminar modelling to predict composite coiled tube failure." APPEA Journal 55, no. 1 (2015): 361. http://dx.doi.org/10.1071/aj14029.
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In a field operation that uses coiled tubing in its applications, fibre-reinforced polymer matrix composite tubing is seldom used. Fibre-composite coiled tubes offer advantages, compared to steel material, through a reduction in weight and improvement in fatigue life. The stiffness of composite material degrades progressively when increasing the number of cyclic loading. The fatigue damage and failure criteria of fibre-reinforced composite coiled tubes are more complex than that of steel; hence, failure predictions are somewhat unreliable. Among the defects in composite materials, interlaminar delamination is the foremost problem in fibre-reinforced composite material, and it leads to a reduction in strength and stiffness especially in cyclic-load conditions. Delamination causes a redistribution of the load path along the composite structure, which is unpredictable; therefore, delamination in a composite coiled tube in an oil and gas field eventually leads to final failure, which could be catastrophic. A-ply-by-ply mathematical modelling and numerical simulation method was developed to predict interlaminar delamination of filament-wound composite coiled tubes under a combination of different loading scenarios with consideration to low-cycle fatigue. The objective of this paper is to explain interlaminar delamination as an initial crack and source of stress concentration in composite coiled tubes in the framework of meso-cracking progression of matrix damage modelling of composite laminates. The paper focuses on delamination failure because the largest span of the composite lifecycle is at the crack propagation phase, which manifests itself in the form of delamination. The analysis shows that the crack front tip is not uniform, and also shows that carbon fibre possesses higher stiffness values compared to glass fibre. The paper confirms that 2D modelling cannot express the real release strain energy rate at the crack front tip. Mode-I testing, however, showed that the double cantilever beam (DCB) only represents the normal stress from the release strain energy rate. The results also indicated that there were other sources contributing to the strain energy release rate, such as inter-layer frictions and normal stress in the end notched flexure (ENF) testing mode.
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Jull, G., C. Barrett, R. Magee, and P. Ho. "Further Clinical Clarification of the Muscle Dysfunction in Cervical Headache." Cephalalgia 19, no. 3 (April 1999): 179–85. http://dx.doi.org/10.1046/j.1468-2982.1999.1903179.x.
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The Headache Classification Committee of the International Headache Society listed impairments in cervical muscle function as criteria for headaches of cervical spine origin. Fifteen subjects with cervical headache and 15 controls were tested for the frequency of abnormal responses to passive stretching and abnormal muscle contraction. A new test of cranio-cervical flexion was used to assess the contraction of the deep neck flexors. Results indicated a trend towards a higher frequency of abnormal response to passive stretching of the muscles examined in the cervical headache group but only the upper trapezius proved significantly different to the control group. Deep neck flexor muscle contraction was significantly inferior in the cervical headache group. From the perspective of physical characterization of cervical headache, it appears mat response from passive stretch of muscle may not be a strong criterion for cervical headache but deep neck flexor performance may have potential to identify musculoskeletal involvement in headache. The finding may also provide positive directions for conservative treatment of cervical headache.
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Akınoğlu, Bihter, Tuğba Kocahan, Necmiye Ün Yıldırım, Çağlar Soylu, Ufuk Apur, and Adnan Hasanoğlu. "A comparison of wrist isokinetic muscle strength in wheelchair table tennis and wheelchair basketball players." Orthopaedic Journal of Sports Medicine 5, no. 2_suppl2 (February 1, 2017): 2325967117S0006. http://dx.doi.org/10.1177/2325967117s00068.
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Aim: The aim of this study was to compare isokinetic muscle strength of wrist flexor and extensor muscles in paralympic athletes. Methods: This study was carried out with the participation of 9 (4 females and 5 males) wheelchair (WC) table tennis players aged 24+3 and 8 male WC basketball players aged 26+3, met the criteria and voluntarly participate in the study. Body weight, height, body mass index and dominant extremity of the study subjects were recorded. İsokinetic measurement were performed with Isomed 2000® device. İsokinetic testing protocol; before the test all players performed the wrist flexion and extension isokinetic test with the 5 repeating at 90º/sec as a warm-up and comprehending the test. Then, wrist flexion and extension concentric-concentric strength measurements were performed with the 5 repeating at 60º/sec and with the 15 repeating at 240º/sec with the angle between 50 degrees of wrist flexion and 60 degrees of wrist extension and peak torque, peak torque/kg values and flexion/extension ratios were recorded. Mann-Whitney U test was used to compare isokinetic muscle strength quantitative variables in athletes. Findings: Isokinetic muscle strength of wrist flexors and extensors was higher in both sides in WC table tennis players with 60º/sec speed (p<0,05). İsokinetic muscle strength of wrist flexors and extensors was higher in both sides in WC basketball players with 240º/sec speed (p<0,05). There was no significant difference statistically between the groups in isokinetic wrist flexion and extansion peak torque/kg ratio in all speeds (p>0,05). Wrist flexion/extension peak torque ratios were similar in both groups. When examining the athletes flexion/extension ratios, wrist extensor muscles were weaker than flexor muscles and flexor muscles were average twice stronger than extensor muscles in both sports ( Table1 ). [Table: see text] Results: We thought that imbalance of muscle strength in the wrist may have occurred because of the use of a WC and requiring the intensive wrist flexors in playing sports. In both groups wrist ekstansor muscles were found to be weaker than wrist flexors and flexor/extensor ratio was found to be imbalance. We believe that all athletes using WC such as WC table tennis and WC basketball players have a strenght imbalance in the muscle of the wrist and as a result, this situation will increase the possibility of injury. Therefore, our study showed that weakness of wrist extensors and imbalance of muscle stenght should be taken into account in WC athletes in athletic training and exercise programs.
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Thiemeier, Thomas, Angelika Bruckner-Foit, and Helmut Kolker. "Influence of the Fracture Criterion on the Failure Prediction of Ceramics Loaded in Biaxial Flexure." Journal of the American Ceramic Society 74, no. 1 (January 1991): 48–52. http://dx.doi.org/10.1111/j.1151-2916.1991.tb07295.x.
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Carda, Stefano, Marco Invernizzi, Gianluca Cognolato, Eugenio Piccoli, Alessio Baricich, and Carlo Cisari. "Efficacy of a Hip Flexion Assist Orthosis in Adults With Hemiparesis After Stroke." Physical Therapy 92, no. 5 (May 1, 2012): 734–39. http://dx.doi.org/10.2522/ptj.20110112.
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Background During gait, the hip flexors generate 40% of the total power. Nevertheless, no device has been tested extensively for clinical purposes to cope with weakness in the hip flexors in patients with stroke. Objective The purpose of this study was to assess the efficacy and safety of a newly developed hip flexion assist orthosis in adult patients with hemiparesis after stroke. Design The study used a prospective, randomized, before-after trial design. The inclusion criteria were hemiparesis resulting from stroke (onset ≥8 weeks); ability to walk, even if with assistance; and hip flexion weakness (Medical Research Council Scale score ≤4). Methods The main outcome measures were the 10-Meter Walk Test and the Six-Minute Walk Test. Patients also were evaluated with the Trunk Control Test, the Functional Ambulation Categories, the Motricity Index, and hip flexor strength on the Medical Research Council Scale. Sixty-two survivors of stroke were tested in random order with and without the orthosis. Any adverse event associated with its use was recorded. Results Both the Six-Minute Walk Test and the 10-Meter Walk Test scores improved with the use of the orthosis. A significant negative correlation was found for improvement between scores on the 2 main outcome measures with the orthosis and the Functional Ambulation Categories scores. The improvement in Six-Minute Walk Test scores with the orthosis was related inversely to hip flexor strength. Conclusions The data showed that the use of a hip flexion assist orthosis can improve gait in patients with poststroke hemiparesis, particularly those with more severe walking impairment.
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Bansal, Manik, Indra Vir Singh, Bhanu K. Mishra, Kamal Sharma, and IA Khan. "A numerical prediction of flexural strength probability for NBG-18 nuclear grade graphite using strength pair model." Journal of Strain Analysis for Engineering Design 52, no. 3 (March 17, 2017): 204–11. http://dx.doi.org/10.1177/0309324717698609.
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In this work, a strength pair model has been proposed for the numerical prediction of flexural strength probability of NBG-18 nuclear grade graphite. The input to the proposed model is a random strength pair of tensile and compressive strengths whose value is based on its probability of occurrence in the experimental data. A finite element–based deterministic numerical approach has been implemented. To account for the large difference in tensile and compressive strengths, Drucker–Prager failure criteria has been implemented. The failure envelope of the Drucker–Prager failure criteria is assumed to have uniaxial fit with Mohr–Coulomb model in the principal stress space. A total of 292 simulations with random pairs of tensile and compressive strength are performed on a three-point bend specimen to obtain a set of flexural strength data. The flexural strength data obtained through numerical simulations are fitted using normal and Weibull distributions. The flexural strength probability obtained from the proposed model is found on conservative side. A goodness-of-fit test concludes that Weibull distribution fits the numerical data better than normal distribution.
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Scollard, C. R., and F. M. Bartlett. "Rehabilitation criteria for post-tensioned voided-slab bridges." Canadian Journal of Civil Engineering 31, no. 6 (December 1, 2004): 977–87. http://dx.doi.org/10.1139/l04-057.
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Current rehabilitation practices for aging, post-tensioned, voided-slab bridges typically reduce the geometric properties of the concrete cross section and so permanently increase post-tensioning stresses, change primary and secondary prestress moments, and create new primary and secondary moments because the original concrete restrains shrinkage of the new concrete. These changes affect the resistance of the rehabilitated bridge at limit states specified for new construction in the Canadian Highway Bridge Design Code (CHBDC) and may cause other limit states not currently identified in the CHBDC to govern. Rehabilitation schemes should be checked for a serviceability limit state of tensile stresses due to permanent service loads that exceed the cracking strength of the original concrete, which is typically not detailed to control crack widths. Ultimate limit states to check are (i) flexural resistance over interior supports, where the total factored demand can be increased markedly by the rehabilitation; and (ii) creep-initiated failure of concrete due to permanent compressive stresses. The application of these procedures is illustrated through example calculations for a typical continuous bridge.Key words: post-tensioned concrete, serviceability, ultimate limit state, restrained shrinkage, secondary prestress moments, critical stress, cracking.
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Smeathers, J. E. "Measurement of Flexural and Torsional Stiffness for the Human Torso in Vivo; Implications for Scoliosis." Engineering in Medicine 16, no. 4 (October 1987): 237–40. http://dx.doi.org/10.1243/emed_jour_1987_016_053_02.
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Voluntary oscillations of the human torso are analysed using engineering beam theory to estimate the flexural and torsional stiffness of the back. Antero-posterior and lateral flexural stiffness are measured as well as the torsional stiffness for both relaxed conditions and at maximum voluntary exertion. The ratio of flexural stiffness in two mutually perpendicular planes is a guide to the torsional stability of a beam in bending. These criteria are used to assess the torsional stability of the human torso when subjected to large bending moments.
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Li, Yang. "Revision for Concrete Members Crack Control Criteria Based on Durability Demand." Applied Mechanics and Materials 578-579 (July 2014): 1489–92. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.1489.
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Based on Monte Carlo method, the concrete durability reliability indexes for typical concrete members in 50-year-period of service were calculated under normally moist environment conditions. By taking the typical concrete members under normally moist environment conditions as example, the fuzzy reliability indexes based on durability for crack control criteria provided in GB 50010-2010 were calculated. The calculation results show that the durability reliability indexes are mainly lower than crack control reliability indexes for normally moist environment conditions. To realize the goal that the durability design safety level can be generally closest to crack control safety level, one revision advice was presented for present concrete design code GB 50010-2010 to properly lower the crack control safety level in normally moist environment conditions: the present short period crack width enlargement coefficient should be multiplied with 0.85 so that the calculation guarantee rate will be lowered to 85% for flexural members.
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Khiem, Nguyen Tien. "On a safety criterion for column-like structure." Vietnam Journal of Mechanics 26, no. 4 (December 31, 2004): 226–36. http://dx.doi.org/10.15625/0866-7136/26/4/5706.
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The practical exploitation of engineering structures needs very much a simple criterion for checking safety of structures instead of reliability index that is very difficult to be computed within the probabilistic theory. This paper deals with establishment of a simple criterion for checking safety of column-like structure based on deterministic analysis. The criterion consists of bound of the flexural displacement at the top of column that is conducted from the displacement analysis combined with ultimate state for the structure.
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White, Richard N., and Peter Smith. "Rehabilitation of Tappan Zee Bridge Using Precast Concrete Composite Deck Units." Transportation Research Record: Journal of the Transportation Research Board 1696, no. 1 (January 2000): 63–72. http://dx.doi.org/10.3141/1696-09.
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The criteria used for successful rehabilitation of decks of major bridges when it is not feasible to close the bridge to traffic are described. These criteria are described with specific reference to recent work on the trestle spans of the Tappan Zee Bridge over the Hudson River near New York City. The results of an experimental program conducted with a full-scale, 10-m-span, lightweight concrete slab-steel beam composite bridge deck unit intended for later use in rehabilitating the through-truss decks of the bridge are also described. Loading history included 107 cycles of flexural fatigue loading followed by a flexural load capacity test. Measured values of capacity and midspan deflection at this ultimate load level are compared with simplified analytical predictions. A description of the actual rehabilitation process used on the Tappan Zee Bridge deck is also provided.
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Pasinato, Fernanda, Juliana Bordin, Clarissa C. Santos-Couto-Paz, Juliana Alves Souza, and Eliane C. R. Corrêa. "Cervical-scapular muscles strength and severity of temporomandibular disorder in women with mechanical neck pain." Fisioterapia em Movimento 29, no. 2 (June 2016): 269–78. http://dx.doi.org/10.1590/0103-5150.029.002.ao05.
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Abstract Introduction: Changes in cervical muscle function have been observed in patients with neck pain (NP) and TMD. However, the relationship between TMD severity and neck muscle strength in the presence/absence of NP is unknown. Objective: To determine the prevalence of TMD in women with and without mechanical NP and assess the cervical-scapular muscle strength and its association with TMD severity. Methods: Fifteen volunteers without neck pain (CG) and 14 women with mechanical neck pain (NPG) took part and were selected by the Neck Disability Index. The diagnosis and severity of TMD were determined by the Research Diagnostic Criteria for TMD and Temporomandibular Index (TI), respectively. The strength of the upper trapezius muscle, and cervical flexor and extensor muscles was measured by digital hand dynamometer. Results: 64.5% of women with NP and 33.3% without NP were diagnosed with TMD (p = 0.095). The NPG showed lower strength of the cervical flexor (p = 0.044) and extensor (p=0.006) muscles, and higher TI (p = 0.038) than in the CG. It was also verified moderate negative correlation between TI and the strength of dominant (p = 0.046, r = -0.547) and non-dominant (p = 0.007, r = -0.695) upper trapezius, and cervical flexors (p = 0.023, r = -0.606) in the NPG. Conclusion: There was no difference in the prevalence of TMD in women with and without NP. However, women with NP have lower cervical muscle strength - compared to those without NP - which was associated with greater severity of TMD. Thus, in women with NP associated with TMD, it is advisable to assess and address the severity of this dysfunction and identify the cervical-scapular muscles compromise.
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Sun, Shu-Fen, Chien-Wei Hsu, Chiao-Wen Hwang, Pei-Te Hsu, Jue-Long Wang, and Chia-Lin Yang. "Application of Combined Botulinum Toxin Type A and Modified Constraint-Induced Movement Therapy for an Individual With Chronic Upper-Extremity Spasticity After Stroke." Physical Therapy 86, no. 10 (October 1, 2006): 1387–97. http://dx.doi.org/10.2522/ptj.20050262.
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Abstract Background and Purpose. Constraint-induced movement therapy (CIMT) is a promising intervention for retraining upper-extremity function after a stroke. The purpose of this case report is to describe the use of a combination of botulinum toxin type A (BtxA) and a modified CIMT program for a patient with severe spasticity who was unable to use his right upper extremity. Case Description. The 52-year-old patient, who had a stroke 4 years ago, did not meet the minimum motor criteria for CIMT benefit. After receiving BtxA injections targeting the elbow, wrist, and finger flexors, he completed a 4-week program of modified CIMT followed by a 5-month home exercise program. Outcomes. The patient exhibited improvement in muscle tone (the velocity-dependent resistance to stretch that muscle exhibits) and in scores on several upper-extremity function tests (Modified Ashworth Scale, Motor Activity Log, Wolf Motor Function Test, Action Research Arm Test, and Fugl-Meyer Assessment of Motor Recovery). He also reported making much progress in the functional use of the involved upper extremity. Discussion. In a patient with severe flexor spasticity and nonuse of the dominant upper extremity after a stroke, a combined treatment of BtxA and modified CIMT may have resulted in improved upper-extremity use.
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Lovy, Andrew J., Nicholas Pulos, Michelle F. Kircher, Robert J. Spinner, Allen T. Bishop, and Alexander Y. Shin. "Factors associated with failed ulnar nerve fascicle to biceps motor branch transfer: a case control study." Journal of Hand Surgery (European Volume) 44, no. 9 (May 23, 2019): 913–19. http://dx.doi.org/10.1177/1753193419851092.
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We sought to identify predictors of failed ulnar nerve fascicle (to flexor carpi ulnaris) to biceps motor branch transfer. A retrospective review of adult brachial plexus patients treated with flexor carpi ulnaris to biceps transfer with a minimum 1-year follow-up was performed. Failure, defined as modified British Medical Research Council grade <3 elbow flexion was compared with randomly selected controls (M ≥ 4−). Ninety-one patients, of which 80% regained >M3 flexion met criteria. Eighteen failures and 18 controls, with similar follow-up (20 vs 23 months) were evaluated. Preoperative flexor carpi ulnaris weakness (M < 5) was significantly more common in failures (78% vs 33%). The rate of flexor carpi ulnaris recovery after operation was significantly higher in controls (86% vs 7%). Increased failure risk can be expected with impaired preoperative flexor carpi ulnaris function. The challenge is how to identify which patients will regain near normal flexor carpi ulnaris strength as excellent outcomes can be obtained. Level of evidence: III
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Foroughi, Mohammad, Marzieh Kadivar, Mohammad Mehdi Nabavi, and Mohammad Reza Kadivar. "The Effect of Silica Nanoparticles and Cellulosic Fibers on the Compressive, Tensile and Flexural Properties of Ordinary Concrete." Advanced Materials Research 261-263 (May 2011): 515–19. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.515.
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The present paper is a laboratory study on the effect of using silica nanoparticles with cellulose fibers in increasing compressive, flexural and tensile strength of concrete and the results has been compared with ordinary concrete made of cement alone. Evaluation is conducted based on a 28-day long period, and a 7-day short period; the results showed that the concrete containing a small percentage of nanoparticles, with a determined ratio of water and cement, in comparison with ordinary concrete with the same water and cement ratio, has improved considerably. For comparison, compressive, flexural and tensile strength of plain concrete and the concrete containing cellulose fibers is also measured. The results show that by each of these three criteria, strength of concrete containing nano-materials and the cellulosic fibers has been increased considerably. Finally, the relationship between compressive, flexural and tensile strength of concrete shows that the tensile and flexural strength of the concrete containing nanoparticles increases by increasing compressive strength.
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Cui, Fengdan, Guoqing Wu, Tian Ma, and Weiping Li. "Effect of Ceramic Properties and Depth-of-penetration Test Parameters on the Ballistic Performance of Armour Ceramics." Defence Science Journal 67, no. 3 (April 25, 2017): 260. http://dx.doi.org/10.14429/dsj.67.10664.
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<p>Through an analysis on the relationship among ceramic properties, the depth of penetration (DOP) test parameters and the ballistic performance of armour ceramics based on literatures, the effects of ceramic type, tile thickness and projectile velocity on the ballistic performance of different kinds of ceramics were investigated systematically. The results show that the ballistic performance of different armour ceramics mainly depends on its density, and by using thin ceramic tiles or under high velocity impact, the ceramic composite armour could not provide effective ballistic protection. Furthermore, the differences in the ballistic performance of armour ceramic are found due to the different ballistic performance criteria and DOP test conditions. Additionally, the slope of the depth of penetration (not include tile thickness) (Pa) versus tile thickness has negative correlation with flexural strength of ceramics, indicating the flexural strength can be one of the criteria to evaluate the performance of armour ceramics.</p>
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Castel, Arnaud, Raoul François, Maria Paola Santisi d’Avila, and Doug Jenkins. "New service limit state criteria for reinforced concrete in chloride environments." Corrosion Reviews 37, no. 1 (January 28, 2019): 21–29. http://dx.doi.org/10.1515/corrrev-2017-0100.
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AbstractIn chloride environments, reinforcement stress limits, intended to control flexural cracking, are one of the most important requirements for service limit state (SLS) design. However, concrete damage at the steel-concrete interface between bending cracks, so called cover-controlled cracking, is always correlated to areas of severe steel reinforcement corrosion. Based on the assumption that cover-controlled cracking should be limited, a model has been developed to provide alternative reinforcement stress limits in marine exposure conditions such as concrete in sea water, including permanently submerged, spray zone and tidal/splash zone, as well as coastal constructions located within 1 km of the shoreline. In this paper, the new reinforcement stress limitation is compared to the Australian Standards AS3600 concrete building code and AS5100.5 concrete bridge code provisions. Analysis shows that the new model is very sensitive to the reinforcement percentage of the cross-section. As a result, the existing AS3600 and AS5100.5 code provisions are more conservative than the new limitation for lightly to normally reinforced concrete cross-section. In this case, crack width control governs the SLS design. However, for normally to heavily reinforced concrete cross-section, the new model provides more conservative results suggesting that cover-controlled cracking governs the SLS design.
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GROBBELAAR, A. O., and D. A. HUDSON. "Flexor Tendon Injuries in Children." Journal of Hand Surgery 19, no. 6 (December 1994): 696–98. http://dx.doi.org/10.1016/0266-7681(94)90237-2.
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Flexor tendon injuries in adults differ from those in children. 38 children (22 male and 16 female) with a mean age of 6.7 years were treated for flexor tendon injuries by primary suture and controlled mobilization between 1985 and 1992. 53 flexor tendons were injured (average 1.5 digits per patient) and the injury most commonly affected the little finger (23 patients). 60% of injuries occurred in zone 2. Using Lister’s criteria, 82% achieved excellent or good results. Repair of both FDS and FDP was better than repair of FDP alone, even in zone 2. There were three tendon ruptures (all classified as poor results) and one other poor result occurred in a zone 2 injury with an associated ulnar nerve palsy. The outcome after flexor tendon repair in children is better than in adults in our hands because rapid healing of tendons occurs in children. No child has yet required tenolysis because in children adhesions are more pliable. Both flexor tendons should be repaired irrespective of the zone of injury. A functional hand can be expected after flexor tendon repair in children.