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Wang, Dong Hong, Bo He, Fei Li, and Bao De Sun. "The Influence of Injection Processing on the Shrinkage Variation and Dimensional Stability of Wax Pattern in Investment Casting." Advanced Materials Research 538-541 (June 2012): 1217–21. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1217.
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The accuracy of the wax patterns used in the investment casting process has a direct bearing on the accuracy of the final cast part. Wax injection process plays a key role in production of nearly net shape wax pattern. Dimension shrinkage is one of the most significant problems of a wax pattern in terms of dimensional stability in the wax injection molding. This study aimed to determine the effects of injection parameters on the dimensional accuracy of the wax patterns. Linear contractions normal to flow direction and weight of wax patterns were measured and dimensional variations were evaluated. The results highlight it is important that when dealing with thick gates, short packing time appears to be the best way to avoid gate area over packing and dimensional variations, high packing pressure appears to increase expansion and dimensional variation of wax pattern.
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Liu, Chang Hui, Sun Jin, Xin Min Lai, Dong Hong Wang, and Yu Lian Wang. "Experimental Study of Injection Conditions for a Thin-Walled Wax Pattern Using Response Surface Methodology." Applied Mechanics and Materials 607 (July 2014): 185–92. http://dx.doi.org/10.4028/www.scientific.net/amm.607.185.
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In this paper, the relationship between the shrinkage of the thin-walled wax part in the investment casting process (ICP) and the process parameters including mold temperature, melt temperature, packing pressure and holding time are investigated through a series of experiments. The relationship is successfully described by a mathematical regression model which is based on the response surface methodology (RSM). The rationality and adequacy of the mathematical model are checked via analysis of variation (ANOVA) and a sensitivity analysis for process parameters on the dimensional shrinkage variation are conducted which shows that the contribution percentages of mold temperature, melt temperature, packing pressure and holding time are 23.77%, 43.67%, 11.85% and 16.99%, respectively. Additionally, the optimal setting of the process parameters is also obtained by calculating the desirability function. The optimal combination of the mold temperature, melt temperature, packing pressure, and holding time is 74°C, 30°C 25bar, and 5 sec, respectively.
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ARAKI, Yoshima, Naoyuki KATAKURA, and Michio KAWAKAMI. "Numerical Analysis of Thermal Stress and Shrinkage of Wax Patterns." Dental Materials Journal 7, no. 2 (1988): 197–205. http://dx.doi.org/10.4012/dmj.7.197.
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Macků, M., and M. Horáček. "Applying RP-FDM Technology to Produce Prototype Castings Using the Investment Casting Method." Archives of Foundry Engineering 12, no. 3 (September 1, 2012): 75–82. http://dx.doi.org/10.2478/v10266-012-0085-y.
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Abstract The research focused on the production of prototype castings, which is mapped out starting from the drawing documentation up to the production of the casting itself. The FDM method was applied for the production of the 3D pattern. Its main objective was to find out what dimensional changes happened during individual production stages, starting from the 3D pattern printing through a silicon mould production, wax patterns casting, making shells, melting out wax from shells and drying, up to the production of the final casting itself. Five measurements of determined dimensions were made during the production, which were processed and evaluated mathematically. A determination of shrinkage and a proposal of measures to maintain the dimensional stability of the final casting so as to meet requirements specified by a customer were the results.
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Nikitin, K. V., V. N. D’yachkov, V. I. Nikitin, A. Yu Barinov, and V. B. Deev. "Influence of temperature conditions on the shrinkage of wax patterns for investment casting." IOP Conference Series: Materials Science and Engineering 919 (September 26, 2020): 022041. http://dx.doi.org/10.1088/1757-899x/919/2/022041.
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Nikitin, K. V., V. N. D’yachkov, V. I. Nikitin, and А. Yu Barinov. "Investigation of linear shrinkage of model compounds and interaction mechanisms in the «lost wax pattern – refractory ceramic mold» system." Izvestiya Vuzov. Tsvetnaya Metallurgiya (Universities' Proceedings Non-Ferrous Metallurgy), no. 6 (December 15, 2019): 621–74. http://dx.doi.org/10.17073/0021-3438-2019-6-42-50.
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Fukada, Ippei, Shunji Takahashi, Masahiko Tanabe, Kazuhiro Araki, Takayuki Kobayashi, Kokoro Kobayashi, Naoya Gomi, et al. "Magnetic resonance imaging with concentric shrinkage as a prognostic factor in patients with luminal breast cancer during neoadjuvant chemotherapy." Journal of Clinical Oncology 31, no. 15_suppl (May 20, 2013): e11587-e11587. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.e11587.
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e11587 Background: The important characteristics of breast cancer is its tumor heterogeneity and response to neoadjuvant chemotherapy (NAC). We analyzed the patterns of tumor shrinkage as a prognostic indicator after NAC for luminal breast cancer. Methods and Results. Methods: Of 854 patients who had received NAC in the single institute between January 2000 and December 2009, 265 luminal breast cancerwere retrospevively examined. Luminal breast cancer was defined as ER and/or PgR positive in more than 10% of cancer cells and HER2 negative (IHC 0, 1+ or FISH <2.0). Before and after NAC, the primary lesion was evaluated by enhanced MRI in 235 patients. Results: The median follow-up period was 51.4 months. 38 patients(16.2%) experienced recurrence after a median DFI of 49.1 months. The median age was 50 and 232 patients received anthracycline containing chemotherapy and 179 patients received taxane. 120 out of 235 patients exhibited concentric shrinkage pattern. Multivariate analysis for DFS identified Age(49>), strong ER/PgR positivity and concentric shrinkage as significantly favorable, and lymph node metastases as significantly unfavorable prognostic factors. Multivariate analysis for OS identified tumor size as significantly unfavorable prognostic factors(p=0.012). Conclusions: the tumor shrinkage pattern could be an important prognostic factor for luminal breast cancer and this suggests that a concentric shrinkage pattern of response may be infrequently associated with chemotherapy-resistant residual cancer cells.
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Omar, M. F. M., S. Sharif, M. Ibrahim, H. Hehsan, M. N. M. Busari, and M. N. Hafsa. "Evaluation of Direct Rapid Prototyping Pattern for Investment Casting." Advanced Materials Research 463-464 (February 2012): 226–33. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.226.
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The ability of rapid prototyping (RP) technology to fabricate direct part of any complex shape as a sacrificial pattern in shorter lead time has benefited the foundry industries significantly. The quality of investment casting (IC) parts is directly related to the master pattern fabricated from RP process. The main objective of this study was to evaluate the quality characteristics of various RP patterns that were fabricated by various RP processes which include 3D Printer (3DP), Fused Deposition Modeling (FDM) and Multijet Modeling (MJM). Evaluation of the RP patterns was carried out on dimensional accuracy, surface roughness and pattern shrinkage. Different internal pattern designs for the RP parts were developed using Insight software for FDM process and Solidworks 2011 for other RP systems. In addition to the quality assessments, the effect of the internal pattern designs on the burn out behaviour of the RP patterns was also evaluated. Experimental results showed that FDM and MJM produced patterns with better accuracy, surface roughness and part shrinkage when compared to 3DP. It was evident that the internal pattern structure improved the accuracy of the patterns produced from all RP processes. Results showed that FDM and MJM processes were superior in terms of mold cleanliness when no residual ash was observed during the burn out stage. Significant oxidation of ceramic powder was observed on the molds of the 3DP patterns which need to be removed manually from the molds.
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Deandrea, Maurilio, Francesca Garino, Mormile Alberto, Roberto Garberoglio, Ruth Rossetto, Nadia Bonelli, Stefano Spiezia, et al. "Radiofrequency ablation for benign thyroid nodules according to different ultrasound features: an Italian multicentre prospective study." European Journal of Endocrinology 180, no. 1 (January 2019): 79–87. http://dx.doi.org/10.1530/eje-18-0685.
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Background The purpose of this study was to confirm the generalisation of radiofrequency ablation (RFA) in the treatment of benign thyroid nodules (BTN) and to look for a correlation between final shrinkage and some ultrasound (US) findings in a large Italian population data set. Methods This prospective study included 337 patients with solid cold BTN from six Italian institutions. Nodule volume, US pattern, thyroid function, symptom/cosmetic scores and complications were evaluated before treatment and at 6 and 12 months. The primary outcome was to find a correlation between basal volume and US pattern of the nodules and final shrinkage. The secondary outcome was to confirm the efficacy and safety of RFA in a large data set. Results The median basal volume was 20.7 mL, and this significantly decreased after RFA at 6 months (7.3 mL (−63.5%), P < 0.001) and at 12 months (6 mL (−70%), P vs 6 months = 0.009). A significant correlation was found for US structure (a spongiform pattern showing a 76% reduction vs 67 and 66% of mix and solid patterns respectively, P < 0.01) as well as for vascularity (intense peripheral and intranodal patterns showing 71 vs 68 and 67% of weak peripheral and intranodal and peripheral patterns respectively, P < 0.03), but not for macrocalcifications. A slight inverse correlation was found between nodule basal volume and shrinkage (Spearman: −0.23). Mean symptoms/cosmetic scores were significantly reduced. No major complications were encountered. Conclusions This multicentre study validated the efficacy and safety of RFA for treating BTN and showed a clear correlation between final shrinkage and some common US findings.
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Ballesio, Laura, Silvia Gigli, Francesca Di Pastena, Guglielmo Giraldi, Lucia Manganaro, Emanuela Anastasi, and Carlo Catalano. "Magnetic resonance imaging tumor regression shrinkage patterns after neoadjuvant chemotherapy in patients with locally advanced breast cancer: Correlation with tumor biological subtypes and pathological response after therapy." Tumor Biology 39, no. 3 (March 2017): 101042831769454. http://dx.doi.org/10.1177/1010428317694540.
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The objective of this study is to analyze magnetic resonance imaging shrinkage pattern of tumor regression after neoadjuvant chemotherapy and to evaluate its relationship with biological subtypes and pathological response. We reviewed the magnetic resonance imaging studies of 51 patients with single mass-enhancing lesions (performed at time 0 and at the II and last cycles of neoadjuvant chemotherapy). Tumors were classified as Luminal A, Luminal B, HER2+, and Triple Negative based on biological and immunohistochemical analysis after core needle biopsy. We classified shrinkage pattern, based on tumor regression morphology on magnetic resonance imaging at the II cycle, as concentric, nodular, and mixed. We assigned a numeric score (0: none; 1: low; 2: medium; 3: high) to the enhancement intensity decrease. Pathological response on the surgical specimen was classified as complete (grade 5), partial (grades 4–3), and non-response (grades 1–2) according to Miller and Payne system. Fisher test was used to relate shrinkage pattern with biological subtypes and final pathological response. Seventeen patients achieved complete response, 25 partial response, and 9 non-response. A total of 13 lesions showed nodular pattern, 20 concentric, and 18 mixed. We found an association between concentric pattern and HER2+ (p < 0.001) and mixed pattern and Luminal A lesions (p < 0.001). We observed a statistical significant correlation between concentric pattern and complete response (p < 0.001) and between mixed pattern and non-response (p = 0.005). Enhancement intensity decrease 3 was associated with complete response (p < 0.001). Shrinkage pattern and enhancement intensity decrease may serve as early response indicators after neoadjuvant chemotherapy. Shrinkage pattern correlates with tumor biological subtypes.
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Peng, Mingkai, John A. Kershaw, Ying Hei Chui, and Meng Gong. "Modelling of tangential, radial, and longitudinal shrinkage after drying in jack pine and white spruce." Canadian Journal of Forest Research 43, no. 8 (August 2013): 742–49. http://dx.doi.org/10.1139/cjfr-2013-0127.
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The purpose of this study was to develop an understanding of the pattern of variation in longitudinal, radial, and tangential shrinkage in two commercially important Canadian wood species using multivariate nonlinear mixed-effects models. Shrinkage data were measured in each growth ring at different heights on trees harvested from a mixed-species Nelder tree-spacing plot located in New Brunswick, Canada. Live crown base was reconstructed based on stem analysis. Cambial age, sampling height, crown characteristics (crown length, crown ratio, and distance to live crown base), and ring width at time of wood formation were used as prediction variables. The results indicated that shrinkage magnitude and pattern were closely related to crown dimensions and stem position at time of wood formation. Trees from wider tree spacings with larger crown lengths and ratios tended to have smaller tangential and radial shrinkage. Longitudinal shrinkage decreased nonlinearly from pith outwards with slower rate changes near the bottom of the trees. The model fixed effects accounted for more variation in jack pine (Pinus banksiana Lamb.) than in white spruce (Picea glauca (Moench) Voss) for shrinkage in the same anatomical direction. After further validation, the model developed can be used to provide shrinkage predictions for lumber distortion models within the framework of an individual tree growth model.
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Horton, Jonathan C., and Davina R. Hocking. "Pattern of ocular dominance columns in human striate cortex in strabismic amblyopia." Visual Neuroscience 13, no. 4 (July 1996): 787–95. http://dx.doi.org/10.1017/s0952523800008658.
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AbstractPrevious experiments in animals have shown that early unilateral eyelid suture, a model of amblyopia induced by cataract, causes shrinkage of ocular dominance columns serving the deprived eye in the striate cortex. It is unknown whether the ocular dominance columns are affected in amblyopia produced by strabismus. We examined specimens of striate cortex obtained postmortem from a 79-year-old woman with a history of amblyopia in her left eye (20/800) since age 2 from accommodative esotropia. Four years prior to her death, she suffered an ischemic infarct of the left optic disc. This injury to the left optic disc made it possible to label the ocular dominance columns using cytochrome oxidase histochemistry. The pattern of ocular dominance columns was reconstructed throughout most of the right striate cortex. No shrinkage of columns was found. In the left cortex only half the column mosaic was labelled, because the patient had some residual vision in the temporal retina of her left eye. The columns within the labelled portion of the overall mosaic appeared normal. These findings indicate that shrinkage of ocular dominance columns does not occur in humans with amblyopia caused by accommodative esotropia. The ocular dominance columns are probably no longer susceptible to shrinkage at the age when most children with this condition begin to develop amblyopia.
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Kobayashi, Shogo, Hidetoshi Eguchi, Masashi Kanai, Hiroshi Wada, Daisuke Sakai, Hideo Baba, Satoru Seo, et al. "Impact of tumor shrinkage pattern by biweekly triplet gemcitabine/cisplatin/s-1 for biliary tract cancers: Implication for neoadjuvant therapy (KHBO1401-1A study)." Journal of Clinical Oncology 37, no. 15_suppl (May 20, 2019): 4093. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.4093.
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4093 Background: There have not been any new evidenced regimen for biliary tract cancers (BTC) after ABC-02 study, we conducted biweekly triplet gemcitabine/cisplatin/s-1 regimen (GCS) and compared with conventional doublet gemcitabine/cisplatin regimen (GC) as phase III (KHBO1401) study. Biweekly GCS was proved not only to prolong patients’ survival (HR 0.791 (90% C.I. 0.628-0.996), one-sided P = 0.046) but also to achieve high response rate (42% versus 15%, P < 0.001) and good conversion rate (2.5% versus 0.0%), and would be good for neoadjuvant therapy. Herein, we investigated tumor shrinkage pattern to explore possibilities of neoadjuvant therapy. Methods: Totally 246 patients were enrolled in multi-center phase III KHBO1401 study between 2014 and 2016. Tumor shrinkage pattern (best response, timing, response at 100 days (14 weeks, approx. 6 cycles in GCS and 4 cycles in GC), etc.) and survival were investigated in the patients with measurable BTC (n = 183, 74%, 91 in GCS and 92 in GC) as sub-analysis. P < 0.05 was considered statistically significant. Results: Tumor shrinkage pattern could be divided to 4 categories by the response at 100 days after enrollment; category A ( < -30% in size), B (-30% to 0%), C (0% to +20%), and D ( > +20%). GCS arm contained more category A & B (61 (67%) vs. 33 (36%), P < 0.0001). Each category predicted best response and overall survival (p < 0.0001). Timing for maximum tumor response were different among categories, category A achieved maximum tumor shrinkage at 165 +/- 76 days in GCS and 225 +/- 190 days in GC, category B at 139 +/- 78 versus 154 +/- 82 days, and category C and D did not achieve tumor shrinkage. Maximum tumor shrinkage in category A was -53% in GCS versus -65% in GC (P = 0.0892), and 20% patients in GCS underwent tumor regrowth 154 +/- 143 days later. Conclusions: GCS provided faster and more tumor shrinkage with better survival in the comparison of GC, although it had 20% risk of re-growth after 6 cycles.
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MUNTEANU, ANDREEA, and RICARD V. SOLÉ. "PATTERN FORMATION IN NOISY SELF-REPLICATING SPOTS." International Journal of Bifurcation and Chaos 16, no. 12 (December 2006): 3679–85. http://dx.doi.org/10.1142/s0218127406017063.
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Among reaction–diffusion systems showing Turing patterns, the diffusive Gray–Scott model [Pearson, 1993], stands out by showing self-replicating patterns (spots), which makes it the ideal simple model for developmental research. A first study of the influence of noise in the Gray–Scott model was performed by Lesmes et al. [2003] concluding that there exists an optimal noise intensity for which spot multiplication is maximal. Here we show in detail the transition from nonspotlike to spotlike pattern, with the identification of a wide range of noise intensities instead of an optimal value for which this transition occurs. Additional studies also reveal that noise produces a shift and a shrinkage of the regions of spatial patterns in the parameters space, without introducing qualitative changes to the diagram.
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Pattnaik, Sarojrani, D. Benny Karunakar, and PK Jha. "A prediction model for the lost wax process through fuzzy-based artificial neural network." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 7 (October 8, 2013): 1259–71. http://dx.doi.org/10.1177/0954406213507701.
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The application of investment casting process is rapidly increasing, specifically for near net shape manufacturing of complex and small engineering components. The process begins with making of wax patterns, thereafter employing a precision mould, dewaxing, pouring molten alloy and knocking the shell, followed by minor finishing operations. This study is about predicting the quality of responses of the wax patterns namely linear shrinkage and surface roughness using fuzzy-based artificial neural network. The process parameters considered are injection temperature, injection pressure and holding time, and experiments have been performed as per Taguchi’s L18 orthogonal array. As optimum parameter levels were different for both the responses, fuzzy logic reasoning has been used to combine all the objectives and transform the experimental results into single performance index known as multi-response performance index. Later, modelling of the process has been done using artificial neural network with experimental process parameters as inputs and multi-response performance index as output obtained from fuzzy modelling. Further, experiments have been conducted at random combination of parameter levels to validate the developed model, and it has been found that the actual results agreed well with that of the predicted value on the basis of mean absolute percentage error and correlation plots.
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Yang, C. C., C. C. Ko, H. Ou Yang, K. F. Chen, Y. Y. Peng, J. W. Liou, C. C. Chou, et al. "Wet Clean Induce Pattern Collapse Mechanism Study." Solid State Phenomena 187 (April 2012): 253–56. http://dx.doi.org/10.4028/www.scientific.net/ssp.187.253.
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Pattern collapse phenomenon was first time observed in BEOL application with the integration of ultra low-k film scheme. With the dimension and pitch shrinkage, the pattern collapse defects are getting worse during wet clean process. In this study, the line collapse defects can be significantly reduced by adding surfactant solution to the rinse liquid. Moreover, higher aspect ratio (>4) will also deteriorate the collapse window. In addition, the kink or bowing trench profile will induce localized stress at the interface. Accordingly, optimization of both wet clean and dry etch process are the successful keys to solve line collapse issue toward future generation and beyond.
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Rashid, Abira. "Optimization of Shrinkage Porosity in Grinding Media Balls by Casting Design Modification and Simulation Technique." International Journal for Research in Applied Science and Engineering Technology 9, no. VIII (August 15, 2021): 344–53. http://dx.doi.org/10.22214/ijraset.2021.37352.
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Shrinkage porosity or cavity are associated with the solidification of the metal either due to gas/air entrapment or when the shrinkage occurring during solidification is not entirely compensated by the riser. Shrinkage cavities occurring in the casting reduces its strength which leads to unfulfillment of the desired serviceability. In this paper, casting design has been modified using the DISA manual to achieve directional solidification which directly relates to improvement of casting quality. The running of metal from pouring basin into casting along with solidification has been analysed through PROCAST which is a casting simulation software based on Finite Element Method and CAFE (Cellular Automata Finite Element) Model. The feeding system of the casting has been modified in terms of shape and volume to minimize air aspiration effect and promote directional solidification. The model used is of grinding media balls casting of high chromium cast iron. The feeding pattern, feeding velocity and solidification with respect to pouring temperature, pouring rate, ambient temperature and film coefficient has been analysed. The final optimum range of all parameters with corresponding minimum shrinkage porosity in casting was obtained. Main aim was to minimize shrinkage porosity in the main casting, ignoring gating and feeding system. The actual minimization of shrinkage porosity comes out around 56 %.
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Sampaio, CS, K.-J. Chiu, E. Farrokhmanesh, M. Janal, RM Puppin-Rontani, M. Giannini, EA Bonfante, PG Coelho, and R. Hirata. "Microcomputed Tomography Evaluation of Polymerization Shrinkage of Class I Flowable Resin Composite Restorations." Operative Dentistry 42, no. 1 (January 1, 2017): E16—E23. http://dx.doi.org/10.2341/15-296-l.
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SUMMARY The present study aimed to characterize the pattern and volume of polymerization shrinkage of flowable resin composites, including one conventional, two bulk fill, and one self-adhesive. Standardized class I preparations (2.5 mm depth × 4 mm length × 4 mm wide) were performed in 24 caries-free human third molars that were randomly divided in four groups, according to the resin composite and adhesive system used: group 1 = Permaflo + Peak Universal Bond (PP); group 2 = Filtek Bulk Fill + Scotchbond Universal (FS); group 3 = Surefil SDR + XP Bond (SX); and group 4 = Vertise flow self-adhering (VE) (n=6). Each tooth was scanned three times using a microcomputed tomography (μCT) apparatus. The first scan was done after the cavity preparation, the second after cavity filling with the flowable resin composite before curing, and the third after it was cured. The μCT images were imported into three-dimensional rendering software, and volumetric polymerization shrinkage percentage was calculated for each sample. Data were submitted to one-way analysis of variance and post hoc comparisons. No significant difference was observed among PP, FS, and VE. SX bulk fill resin composite presented the lowest values of volumetric shrinkage. Shrinkage was mostly observed along the occlusal surface and part of the pulpal floor. In conclusion, polymerization shrinkage outcomes in a 2.5-mm deep class I cavity were material dependent, although most materials did not differ. The location of shrinkage was mainly at the occlusal surface.
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Kuo, Chil Chyuan, Ying Jie Wang, and Zhong Sheng Shi. "Development of a High Precision Silicone Rubber Mold for Cylinder Block." Applied Mechanics and Materials 459 (October 2013): 342–48. http://dx.doi.org/10.4028/www.scientific.net/amm.459.342.
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This work demonstrates a technique for producing accurate wax patterns made from a high precision silicone rubber mold. Silicon rubber mold was cut into five components, which is the minimum number of components for assembling the silicone rubber mold. The advantages of this silicon rubber mold include savings in assembly time, reduction of human error while assembling the silicone rubber mold and good assembly precision. The shrinkage of critical dimensions can be controlled within 2.19%. Results reported here can speed up the velocity in the development of a new cylinder block in the motorcycle industry.
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Mutuli, Gibson P., Duncan O. Mbuge, and Ayub N. Gitau. "Mathematical Modelling, Moisture Transport, Shrinkage and Nutrient Content Properties in Drying Selected African Leafy Vegetables." Applied Engineering in Agriculture 36, no. 1 (2020): 95–104. http://dx.doi.org/10.13031/aea.13532.
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HighlightsPage model best described their drying pattern at moisture content above 0.5 w.b.Shrinkage linearly correlates to moisture loss.Activation energy correlates to air temperature.Vitamins A, C, and E are preserved by drying and storage. ABSTRACT. The study investigated physical, thermodynamic, and nutritional properties with drying and storage of selected African green leafy vegetables. The vegetables studied were: (Jute Mallow), (Slender Leaf), (Cowpea), (Nightshade), and (Amaranthus). Drying experiment was done at 30°C, 40°C, and 50°C in a convective laboratory dryer and drying was pattern fitted to existing models, moisture diffusivity, and activation energy trends were determined, shrinkage was determined from change in leaf thickness, and vitamins A, C, and E were analyzed using spectroscopy and high-pressure liquid chromatography as freshly harvested and after drying at 40°C and storage for 60 days. Results showed that drying occurred in the falling rate period and Page model could simulate the drying pattern of the vegetables with a ˜97% correlation between the empirical and predicted values with the model prediction being precise above 0.5 moisture content on wet basis (w.b.). Shrinkage was found to be a function of moisture loss at a range of 89% to 98% linear correlation. The rate of moisture loss and activation energy correlated with air temperature. The trend in the drying characteristics and moisture transport of the vegetables was unique with each vegetable. Drying at 40°C and storage for 60 days realized a retention in the scale range of 50% to 75% for vitamins A, C, and E. The study showed that drying is an effective way to preserve the vegetables. Keywords: Mathematical modeling, Mass transfer, Nutrient preservation, Shrinkage, Thermodynamic properties.
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Mansmann, Ulrich Robert, Ruediger P. Laubender, Clemens Albrecht Giessen, Ute Sartorius, and Volker Heinemann. "Validating the prognostic relevance of initial change in tumor size using a series of therapeutic regimens for patients with metastatic colorectal cancer (mCRC)." Journal of Clinical Oncology 30, no. 4_suppl (February 1, 2012): 580. http://dx.doi.org/10.1200/jco.2012.30.4_suppl.580.
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580 Background: Piessevaux et al. (ESMO 2010, Abstr. #596P) proposed a decrease in tumor size of 20% at week 8 following 1st-line therapy for mCRC as a predictor of clinical outcome (PFS and OS). Based on the results of a single study Suzuki et al. (Ann. Oncol. 2011) also claimed that change in tumor size at the first follow-up CT scan was strongly prognostic for PFS and OS in mCRC. It is of interest to validate these findings in different treatment regimens. Methods: Based on data from 4 randomized trials (FIRE-1, n = 479; CIOX, n = 185; OPUS, n = 337; CRYSTAL, n = 1198) a total of 6 treatment regimens were studied (mIROX/FUFIRI, CAPIRI/CAPOX + cetuximab, FOLFOX4 + cetuximab, FOLFOX4, FOLFIRI + cetuximab, FOLFIRI). A joint model was used to quantify the non-linear, J-shaped individual relationships between time and largest diameter (LD) and incorporate them into the formal risk calculation for PFS and OS. The first radiological tumor assessment was performed weeks 7-9 after the start of treatment and relative tumor shrinkage compared to baseline evaluated. Results: All 6 groups showed a consistent pattern for PFS and OS. Distinctive shrinkage week 8 (weeks 7-9) was associated with an improved individual prognosis (p<0.0001 in each group). This was even more pronounced for larger sized tumors (LD >100 mm) at baseline (p<0.01 in each group). Distinctive individual shrinkage for a corresponding treatment was defined as shrinkage exceeding the 8 week shrinkage of its mean tumor kinetics. Distinctive shrinkage for the 3 combination chemotherapy regimens was observed with individual shrinkage above 16%, 23%, or 26%. For the 3 combination chemotherapy regimens + cetuximab distinctive shrinkage was reached if individual shrinkage was greater than 21%, 24%, and 29% respectively, independent of KRAS status. Predictivity has not yet been examined. Conclusions: Our results validate the prognostic relevance of the 20% cut-off for shrinkage at week 8. Early tumor shrinkage is a promising surrogate for PFS and OS using a variety of therapeutic regimens for mCRC. These data may serve as a basis for modifying the widely adopted RECIST criteria in favor of modified response evaluation criteria.
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Paul, Rajendra D., and Martin G. Helander. "Effect of Sit-Stand Schedule on Spinal Shrinkage fn VDT Operators." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 39, no. 10 (October 1995): 563–67. http://dx.doi.org/10.1177/154193129503901005.
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A controlled field study was conducted to measure spinal shrinkage in office employees with sit-stand type workstations. Thirteen office employees, ten healthy and three with spinal disorders participated in the study. Using a stadiometer, changes in stature were measured at 8 a.m., 12 p.m., 1 p.m. and 5 p.m. From 12 p.m. to 1 p.m., all subjects sat for 40 minutes and walked for 20 minutes. Out of the ten healthy employees, six were instructed to stand for 30 minutes four times during the day. The remaining four subjects stood eight times 15 minutes each. Office workers who stood in 30 minute sessions experienced significantly less shrinkage than those who stood in 15 minute sessions. Office workers with spinal disorders also stood eight times 15 minutes each. They incurred a greater variability in the shrinkage pattern.
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Tripathy, S., KS Subba Rao, and D. G. Fredlund. "Water content - void ratio swell-shrink paths of compacted expansive soils." Canadian Geotechnical Journal 39, no. 4 (August 1, 2002): 938–59. http://dx.doi.org/10.1139/t02-022.
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This paper addresses the behaviour of compacted expansive soils under swellshrink cycles. Laboratory cyclic swellshrink tests were conducted on compacted specimens of two expansive soils at surcharge pressures of 6.25, 50.00, and 100.00 kPa. The void ratio and water content of the specimens at several intermediate stages during swelling until the end of swelling and during shrinkage until the end of shrinkage were determined to trace the water content versus void ratio paths with an increasing number of swellshrink cycles. The test results showed that the swellshrink path was reversible once the soil reached an equilibrium stage where the vertical deformations during swelling and shrinkage were the same. This usually occurred after about four swellshrink cycles. The swelling and shrinkage path of each specimen subjected to full swelling full shrinkage cycles showed an S-shaped curve (two curvilinear portions and a linear portion). However, the swelling and shrinkage path occurred as a part of the S-shaped curve, when the specimen was subjected to full swelling partial shrinkage cycles. More than 80% of the total volumetric change and more than 50% of the total vertical deformation occurred in the central linear portion of the S-shaped curve. The volumetric change was essentially parallel to the saturation line within a degree of saturation range of 5080% for the equilibrium cycle. The primary value of the swellshrink path is to provide information regarding the void ratio change that would occur for a given change in water content for any possible swellshrink pattern. It is suggested that these swellshrink paths can be established with a limited number of tests in the laboratory.Key words: expansive soils, oedometer tests, swellshrink behaviour, shrinkage tests.
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Zhang, Pei, Feng Shan Du, Zhi Qiang Xu, and Ling Ling Zhao. "Numerical Simulation on the Dendritic Spacing and Microporosity in A356 Alloy Ingot." Materials Science Forum 575-578 (April 2008): 115–20. http://dx.doi.org/10.4028/www.scientific.net/msf.575-578.115.
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A stochastic mathematic model contained the effects of dendrite morphology, solidification shrinkage and dissolved gases was formed to simulate microporosity formation and growth. Microporosities appear in the interspaces of primary dendrites as well as secondary dendrites from microscopic view of A356 aluminum alloy experimental ingot with a metal mold. In the past literatures it took the volumetric fraction of microporosities as a function of the local density. In the present work a single pore size and distribution were predicted concerning the combination of shrinkage and dissolved gases and dendritic spacing. The dendritic spacing is a main parameter to decide the pore pattern. For shrinkage and dissolved gases causes, the favorable one is determined by dendritic spacing, also the local cool rate and tip growth rate. The dense degree of the experimental ingots in different casting conditions was discussed. The variations of dens degree from the measured values in different casting conditions are similar to that of porosity volume fraction from the predicted results.
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Rozana, Rozana, Daud Perdana, and Oktavia Nurmawaty Sigiro. "SIMULASI TRANSPORTASI TOMAT DAN PERUBAHAN MUTU TOMAT SELAMA PENYIMPANAN." Journal of Food Technology and Agroindustry 3, no. 1 (February 23, 2021): 13–20. http://dx.doi.org/10.24929/jfta.v3i1.1209.
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Chemical, physical, and microbiological damage of fruits and vegetables can occur during the transportation process. The percentage of damage can reach 30-50% if the treatment during transportation is not carried out properly. The research objective was to determine the quality changes in tomatoes after transportation simulation based on the arrangement of the fruit in cardboard packaging. The treatment in this research is tomato arrangement patterns: the face centered cubic (FCC) arrangement, the traditional arrangement and the jumble (farmer) arrangement. The research begins with a transportation simulation using a vibrating table in a vertical direction, using a frequency range of 3.9 Hz and an amplitude of 5.2 cm. The simulation is carried out in 1 hour. After the simulation at the 1st hour, amount of mechanical damage (bruising) on every package was carried out. The results showed that the pattern of arranging tomatoes in cardboard packaging that gave the least damage was the FCC arrangement pattern. The FCC pattern only causes shrinkage of 0.11% and the smallest amount of mechanical damage (bruising) is 0.64%.
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Al-Jeznawi, Duaa, Marcelo Sanchez, and Abbas J. Al-Taie. "Effect of Wetting-Drying Cycles on Desiccation Crack Pattern and Soil Behavior." Key Engineering Materials 857 (August 2020): 188–94. http://dx.doi.org/10.4028/www.scientific.net/kem.857.188.
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Cracking, shrinkage, and curling of soils, in general, take place due to drying. These deformations lead to many problems include the development of main paths for water flow and pollutant transport, reduction of soil strength (and impact on other mechanical properties of soils), erosion in slopes, landslides, increase infiltration capacity of the soil and the differential settlement problems. Few studies have investigated the effect of wetting-drying (W-D) cycles on desiccation cracks of soils. The effect of multiple wetting-drying cycles in the cracking behavior was investigated in this research by performing several wetting-drying (W-D) cycles on the initially saturated samples (of pure kaolinite and a mixture of kaolinite with bentonite) under the lab atmosphere (24 ± 1 °C, and 52 ± 2% of RH). The weight of each sample was monitored using a computerized scale (with an accuracy of 0.01 g) connected to the computer. During the test, the water evaporation path with the development of surface cracks and volume shrinkage was monitored by means of digital images. It was observed that the crack patterns changed during the initial cycles, but there was an equilibrium state in the third and fourth W-D cycles. Additionally, it was observed that the main cracks formed in the first dry path were virtually closed after 10 minutes of the second wetting path; in the meantime, small cracks (fissures) were initiated after this wetting process. It was, also, detected that soils with high plasticity required more W-D cycles to reach the equilibrium condition than soils with low plasticity. The results of these experiments are useful for understanding the effect of different seasons on soil behavior.
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Berkmann, Sven, Sven Schlaffer, and Michael Buchfelder. "Tumor shrinkage after transsphenoidal surgery for nonfunctioning pituitary adenoma." Journal of Neurosurgery 119, no. 6 (December 2013): 1447–52. http://dx.doi.org/10.3171/2013.8.jns13790.
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Object Volume reduction of nonfunctioning pituitary adenomas has been described, for example, after radiotherapy and pituitary tumor apoplexy. Even when considerable remnants remain after surgery, spontaneous shrinkage and relief of mass lesion symptoms can sometimes occur. The aim of this study was to assess shrinkage of tumor residues after transsphenoidal surgery and to identify predictors of tumor shrinkage. Methods A total of 140 patients with postoperative remnants of nonfunctioning pituitary adenomas treated at the Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany, were included in this study. All patients underwent transsphenoidal procedures with guidance by 1.5-T intraoperative MRI. The intraoperative images of remnants were compared with images taken at 3 months and at 1 year after surgery. The possible predictors analyzed were age; sex; preoperative and intraoperative tumor dimensions; tumor growth pattern; endocrinological, ophthalmological, and histological characteristics; and history of previous pituitary surgery. For statistical analyses, the Fisher's exact test, Mann-Whitney U-test, and multivariate regression table analysis were used. Results Follow-up imaging 3 months after surgery showed tumor remnant shrinkage of 0.5 ± 0.6 cm3 for 70 (50%) patients. This reduction was 89% ± 20% of the residual volume depicted by intraoperative MRI. In 45 (64%) patients, the remnants disappeared completely. Age, sex, and preoperative tumor volume did not significantly differ between the shrinkage and no-shrinkage groups. Positive predictors for postoperative shrinkage were cystic tumor growth (p = 0.02), additional resection of tumor remnants guided by intraoperative MRI (p = 0.04), smaller tumor volume (p = 0.04), and smaller craniocaudal tumor diameter of remnants (p = 0.0014). Negative predictors were growth into the cavernous sinus (p = 0.009), history of previous pituitary surgery (p = 0.0006) and tumor recurrence (p = 0.04), and preoperative panhypopituitarism (p = 0.04). Multivariate regression analysis indicated a positive correlation between tumor shrinkage and smaller tumor remnants (p < 0.0001) and no history of previous pituitary surgery (p = 0.003). No spontaneous change in tumor remnant volume was detected between 3 months and 1 year postoperatively. During a mean follow-up time of 2.7 years, 1 (2%) patient with postoperative tumor shrinkage had to undergo another operation because of tumor progression. Conclusions Spontaneous volume reduction of nonfunctioning pituitary adenoma remnants can occur within 3 months after surgery. Predictors of shrinkage are smaller tumor remnant volume and no history of previous pituitary surgery.
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Kaisarly, Dalia, D. Meierhofer, M. El Gezawi, P. Rösch, and K. H. Kunzelmann. "Effects of flowable liners on the shrinkage vectors of bulk-fill composites." Clinical Oral Investigations 25, no. 8 (January 27, 2021): 4927–40. http://dx.doi.org/10.1007/s00784-021-03801-2.
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Abstract Objectives This investigation evaluated the effect of flowable liners beneath a composite restoration applied via different methods on the pattern of shrinkage vectors. Methods Forty molars were divided into five groups (n = 8), and cylindrical cavities were prepared and bonded with a self-etch adhesive (AdheSe). Tetric EvoCeram Bulk Fill (TBF) was used as the filling material in all cavities. The flowable liners Tetric EvoFlow Bulk Fill (TEF) and SDR were used to line the cavity floor. In gp1-TBF, the flowable composite was not used. TEF was applied in a thin layer in gp2-fl/TEF + TBF and gp3-fl/TEF + TBFincremental. Two flowable composites with a layer thickness of 2 mm were compared in gp4-fl/TEF + TBF and gp5-fl/SDR + TBF. TEF and SDR were mixed with radiolucent glass beads, while air bubbles inherently present in TBF served as markers. Each material application was scanned twice by micro-computed tomography before and after light curing. Scans were subjected to image segmentation for calculation of the shrinkage vectors. Results The absence of a flowable liner resulted in the greatest shrinkage vectors. A thin flowable liner (gp2-fl/TEF + TBFbulk) resulted in larger overall shrinkage vectors for the whole restoration than a thick flowable liner (gp4-fl/TEF + TBF). A thin flowable liner and incremental application (gp3-fl/TEF + TBFincremental) yielded the smallest shrinkage vectors. SDR yielded slightly smaller shrinkage vectors for the whole restoration than that observed in gp4-fl/TEF + TBF. Conclusions Thick flowable liner layers had a more pronounced stress-relieving effect than thin layers regardless of the flowable liner type. Clinical relevance It is recommended to apply a flowable liner (thin or thick) beneath bulk-fill composites, preferably incrementally.
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Mi, Guo Fa, Xiang Yu Liu, Kuang Fei Wang, and Ji Tai Niu. "Numerical Simulation for Low Pressure Die Casting of Al-Alloy Motor Enclosure and Technology Improvement." Materials Science Forum 575-578 (April 2008): 1389–95. http://dx.doi.org/10.4028/www.scientific.net/msf.575-578.1389.
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The FDM numerical simulation software, View-Cast system, was employed to simulate the mould-filling and solidification process in low pressure die casting (LPDC) of Al-alloy motor enclosure. The distribution of liquid fraction, temperature field and the solidification pattern of casting were revealed and the formation mechanism as well as distribution rule of the potential defects, namely gas pores and shrinkage pores, were predicted. Furthermore the solutions to eliminate them were presented. By reducing the pouring rate, the turbulent flow at the corner of casting had eased, so the gas pores could be eliminated. Then the force-cooling system was installed on the top of mould, which could reduce the volume of liquid islands efficiently so that the shrinkage defects can be decreased to its limit.
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Purghé, F., and A. Olivero. "Phenomenal Shrinkage and Expansion of Visual Surfaces: Is Amodal Completion a Factor?" Perception 26, no. 1_suppl (August 1997): 320. http://dx.doi.org/10.1068/v970189.
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When two figures intersect, two apparently paradoxical size effects take place (Kanizsa, 1979 Organization in Vision chapter 11): (1) the partly occluded figure looks shorter than an identical unoccluded figure, and (2) the modally visible parts of the occluded figure look larger than identical isolated parts. Kanizsa explains such effects as due to amodal completion. Three experiments were carried out by the method of adjustment to test this explanation: two were devoted to the shrinkage effect, and the third one was devoted to the expansion effect. The first experiment exploited the properties of the so-called Helmholtz - Ratoosh law (T-shaped vs Y-shaped junctions) to test whether a figural shrinkage is also present in a pattern in which amodal completion should not occur. The second experiment was aimed at checking whether stereoscopic displacement of the ‘occluded’ figure ‘behind’ or ‘in front of’ the ‘occluding’ one is capable of affecting the amount of shrinkage. In the third experiment the Helmholtz - Ratoosh law was again applied to the expansion. The results of all three experiments converge in showing that the amount of shrinkage of the whole ‘occluded’ figure as well as the ammount of expansion of the ‘modally visible’ parts are not affected by the presence or the absence of amodal completion. We conclude that both the shrinkage and the expansion effects are due to other factors, probably the same factors as those that affect classical optical-geometrical illusions, such as the Oppel - Kundt or the horizontal - vertical illusions.
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Khan, Sajid U., and Johan E. ten Elshof. "Patterning Luminescent Nanocrystalline : Eu and : Tb Particles Embedded in Hybrid Organosilica with Soft-Lithographic Techniques." Journal of Nanomaterials 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/279810.
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Eu3+-doped LaPO4and Tb3+-doped CePO4luminescent nanoparticles embedded in hybrid organosilica were patterned by two soft lithographic techniques. The role of various parameters such as solution chemistry, thermal protocols, and modification of the mold-substrate surface energies related to pattern shape formation and adhesion to the substrates have been studied. The shrinkage of the oxide patterns and shape evolution during the process was also examined. The patterns were characterized with optical and photoluminescence (PL) microscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Compositional analyses were carried out with X-ray photoelectron spectroscopy (XPS), low-energy ion scattering (LEIS), and secondary ion mass spectroscopy (SIMS). The results indicated that the final patterns obtained with these two techniques for the same material have different shapes and adherence to the substrates.
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Gracie, A. J., and P. H. Brown. "Effects of climatic factors, fluctuating water availability and partial defoliation on the diurnal radial growth pattern of carrot (Daucus carota) taproots." Australian Journal of Experimental Agriculture 44, no. 12 (2004): 1231. http://dx.doi.org/10.1071/ea03040.
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Carrot taproots are prone to radial longitudinal tissue fractures (splitting). The longitudinal alignment of the fractures is consistent with the tangential stress induced by radial growth in the annular cambium. In this study linear variable differential transformers were used to monitor the diurnal radial growth pattern of mature carrot taproots. The diurnal growth pattern was characterised by rapid expansion during the night (dark) period and small shrinkage during the light period. The magnitude of the daily shrinkage was positively correlated with both vapour pressure deficit and global radiation. A positive correlation between the rate of taproot expansion during the night period and global radiation level the preceding day was also recorded. Water stress reduced the taproot night time expansion rate, but the taproot of water stressed plants expanded rapidly when watered to field capacity. Partial defoliation of plants at midday resulted in immediate expansion of the taproot, however, the daily growth rates of the partially defoliated plants was less than untreated control plants over the following 3 days. It was concluded that the short-term changes in taproot diameter could be used to infer changes in tangential stresses and therefore taproot splitting propensity.
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Horton, Jonathan C., Davina R. Hocking, and Lynne Kiorpes. "Pattern of ocular dominance columns and cytochrome oxidase activity in a macaque monkey with naturally occurring anisometropic amblyopia." Visual Neuroscience 14, no. 4 (July 1997): 681–89. http://dx.doi.org/10.1017/s0952523800012645.
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AbstractUnilateral eyelid suture, a model for amblyopia induced by congenital cataract, produces shrinkage of the deprived eye's ocular dominance columns in the striate cortex. Loss of geniculocortical projections are thought to account for the poor vision in the amblyopic eye. It is uncertain whether ocular dominance columns become shrunken in other forms of amblyopia. We examined the striate cortex in a pigtailed macaque with natural anisometropia discovered at age 5 months. Amblyopia in the left eye was documented at 1 year by behavioral testing. At age 6 years, the left eye was injected with [3H]proline and the striate cortex was processed for autoradiography and cytochrome oxidase (CO). The ocular dominance columns in layer IVc labelled with [3H]proline were normal. CO staining showed a novel pattern of thin dark bands in layer IV. These bands occupied the core zones at the center of the ocular dominance columns. Their appearance resulted from relative loss of CO activity along the borders of the ocular dominance columns, regions specialized for binocular processing. These findings indicate that not all forms of amblyopia are accompanied by shrinkage of ocular dominance columns. The unusual pattern of CO staining in layer IVc reflected a subtle alteration in metabolic activity which may have resulted from impairment of binocular function in anisometropic amblyopia.
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Yonemori, Fumihiko, Tohru Yamaguchi, Hideki Yamada, and Akira Tamura. "Spatial Cognitive Performance after Chronic Focal Cerebral Ischemia in Rats." Journal of Cerebral Blood Flow & Metabolism 19, no. 5 (May 1999): 483–94. http://dx.doi.org/10.1097/00004647-199905000-00002.
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The authors investigated the impairment of spatial cognitive performance in rats with chronic focal cerebral ischemia using the Morris maze, and examined the correlation between this deficit and other behavioral changes, such as step-through latency in passive avoidance task and neurologic score, or pathologic changes. The authors focused on the relationship between the damaged brain region and the affected spatial learning behavior. In the Morris maze task at 8 weeks after the middle cerebral artery (MCA) occlusion, escape latency, swimming path length, and percent time spent in goal quadrant of MCA-occluded rats were impaired, which correlated with shrinkage of the cortex involving parietal cortex, but not caudate-putamen (CP). Middle cerebral artery-occluded rats were also impaired in the percent time spent in the outermost annulus and in turning ratio, which significantly correlated with shrinkage of CP, but not cortex. Middle cerebral artery-occluded rats showed two typical search patterns; one was almost the same as that of sham-operated and intact rats, and the other was round shaped and had less turning behavior. Both subgroups of MCA-occluded rats divided by turning ratio had significantly impaired spatial cognitive performance, which indicates that the changes of search pattern did not affect cognitive performance in the Morris maze. The neurologic deficits recovered gradually after MCA occlusion, which correlated with shrinkage of cortex and CP. The step-through latency in passive avoidance task of the MCA-occluded rats was impaired, but did not correlate with shrinkage of cortex or CP. These results suggest that the long-term spatial cognitive deficit of MCA-occluded rats is in part associated with damage to the cortex involving parietal cortex, and that the change of search strategies is associated with damage to CP. These findings support the idea that different brain regions contribute differently to cognitive performance, search strategies, avoidance task, and neurologic performance, and may be useful for estimating the related region of functional disorder in the clinical situation.
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Abasolo, Willie P., Masato Yoshida, Hiroyuki Yamamoto, and Takashi Okuyama. "Microfibril Angle Determination of Rattan Fibers and its Influence on the Properties of the Cane." Holzforschung 54, no. 4 (July 4, 2000): 437–42. http://dx.doi.org/10.1515/hf.2000.072.
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Summary The microfibril angle of rattan fibers was determined using the iodine staining method and the X-ray diffraction technique. The two were compared to assess the applicability of the X-ray technique in estimating the actual microfibril angle (MFA) of the fiber walls. Likewise, longitudinal Young's modulus and longitudinal shrinkage were evaluated to determine the influence of MFA on the properties of the cane. The X-ray technique gave an accurate and objective estimate of the actual MFA of the fiber walls. A nonlinear relationship existed between MFA and longitudinal Young's modulus while a curvilinear relationship was observed between MFA and longitudinal shrinkage. This pattern is similar to the behavior of wood. Thus, it was deduced that the influence of microfibril angle on the properties of rattan cane is similar to its influence on the properties of wood.
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Chokkalingam, B., V. Raja, J. Anburaj, R. Immanual, and M. Dhineshkumar. "Investigation of Shrinkage Defect in Castings by Quantitative Ishikawa Diagram." Archives of Foundry Engineering 17, no. 1 (March 1, 2017): 174–78. http://dx.doi.org/10.1515/afe-2017-0032.
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Abstract Metal casting process involves processes such as pattern making, moulding and melting etc. Casting defects occur due to combination of various processes even though efforts are taken to control them. The first step in the defect analysis is to identify the major casting defect among the many casting defects. Then the analysis is to be made to find the root cause of the particular defect. Moreover, it is especially difficult to identify the root causes of the defect. Therefore, a systematic method is required to identify the root cause of the defect among possible causes, consequently specific remedial measures have to be implemented to control them. This paper presents a systematic procedure to identify the root cause of shrinkage defect in an automobile body casting (SG 500/7) and control it by the application of Pareto chart and Ishikawa diagram. with quantitative Weightage. It was found that the root causes were larger volume section in the cope, insufficient feeding of riser and insufficient poured metal in the riser. The necessary remedial measures were taken and castings were reproduced. The shrinkage defect in the castings was completely eliminated.
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Dong, Baiyu, Yang Ye, Shixue You, Qiming Zheng, Lingyan Huang, Congmou Zhu, Cheng Tong, Sinan Li, Yongjun Li, and Ke Wang. "Identifying and Classifying Shrinking Cities Using Long-Term Continuous Night-Time Light Time Series." Remote Sensing 13, no. 16 (August 8, 2021): 3142. http://dx.doi.org/10.3390/rs13163142.
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Shrinking cities—cities suffering from population and economic decline—has become a pressing societal issue of worldwide concern. While night-time light (NTL) data have been applied as an important tool for the identification of shrinking cities, the current methods are constrained and biased by the lack of using long-term continuous NTL time series and the use of unidimensional indices. In this study, we proposed a novel method to identify and classify shrinking cities by long-term continuous NTL time series and population data, and applied the method in northeastern China (NEC) from 1996 to 2020. First, we established a long-term consistent NTL time series by applying a geographically weighted regression model to two distinct NTL datasets. Then, we generated NTL index (NI) and population index (PI) by random forest model and the slope of population data, respectively. Finally, we developed a shrinking city index (SCI), based on NI and PI to identify and classify city shrinkage. The results showed that the shrinkage pattern of NEC in 1996–2009 (stage 1) and 2010–2020 (stage 2) was quite different. From stage 1 to stage 2, the shrinkage situation worsened as the number of shrinking cities increased from 102 to 162, and the proportion of severe shrinkage increased from 9.2% to 30.3%. In stage 2, 85.4% of the cities exhibited population decline, and 15.7% of the cities displayed an NTL decrease, suggesting that the changes in NTL and population were not synchronized. Our proposed method provides a robust and long-term characterization of city shrinkage and is beneficial to provide valuable information for sustainable urban planning and decision-making.
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Podder, Debarata, Amith Gadagi, Nisith Ranjan Mandal, and Sreekanta Das. "In Sight of a Fillet Joint Based on Welding Force Method." Journal of Ship Production and Design 32, no. 04 (November 1, 2016): 206–15. http://dx.doi.org/10.5957/jspd.2016.32.4.206.
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Analysis of fillet-welded T-sections was carried out using the commercial finite element software ANSYS® for SM400A shipbuilding steel. To avoid the time consuming experimental technique, this model was validated with the existing experimental and numerical results. The vertical deflection, transverse shrinkage, and longitudinal residual stress were considered to validate the present model. After validating the model, the longitudinal, transverse, and normal plastic strains were collected from flange, web, and weld bead portions throughout the thickness and were averaged. These plastic strains were converted into corresponding longitudinal, transverse, and normal welding forces and were applied in an elastic model to obtain the distortions. The average welding force method was found to be very efficient in determining the distortions of welded structures. It was found that the proper distortion pattern for single-sided fillet welding can be obtained by incorporating the additional shrinkage forces from the weld bead.
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Hai, Phi Hong, B. Hannrup, C. Harwood, G. Jansson, and Do Van Ban. "Wood stiffness and strength as selection traits for sawn timber in Acacia auriculiformis." Canadian Journal of Forest Research 40, no. 2 (February 2010): 322–29. http://dx.doi.org/10.1139/x09-191.
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Acacia auriculiformis A. Cunn. ex Benth. is an important planting tree species, but little attention has been paid to its wood properties, such as shrinkage, stiffness, strength, and basic density, which are important for use in structural and appearance-grade timber applications. Here we report the genetic variation in static bending stiffness and strength of wood in a 5½-year-old clone trial in southern Vietnam and the genotypic correlations among these traits and tree diameter, wood shrinkage, and basic density. There was significant variation in stiffness and strength among 40 randomly selected clones. Clonal repeatability (H2) was high for stiffness and moderate for strength. There was no consistent pattern of difference between heartwood and sapwood for the estimates of H2 for stiffness and strength, whereas the estimates of H2 were lower for heartwood density than for sapwood density. Diameter showed a significant negative genotypic correlation with stiffness but a nonsignificant correlation with strength. Genotypic correlations between density and stiffness, and density and strength, were positive, but only the latter was significant. Stiffness and strength were not significantly correlated with wood shrinkage. There is potential to simultaneously improve tree growth, wood basic density, and the mechanical properties of juvenile wood of this species.
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Šrámek, Jaromír, Aneta Pierzynová, and Tomáš Kučera. "THE FRACTAL DIMENSION-BASED DESCRIPTOR OF THE MICROVASCULAR PATTERN ON THE HISTOLOGICAL SECTION." Lékař a technika - Clinician and Technology 49, no. 3 (March 19, 2020): 83–86. http://dx.doi.org/10.14311/ctj.2019.3.02.
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The microvascular pattern in the histological section, i.e. the point-pattern composed of capillaries perpendicular to the plane of section, contains information about the three-dimensional structure of the capillary network. Histological processing is followed by the shrinkage of tissue of uncertain magnitude. In order to obtain relevant information, the scale-independent analysis is necessary. We used an approach based on the Minkowski cover of measured set. The true fractal dimension of the point pattern is obviously of zero, but the artificial result of the algorithm can be related to the complexity of shape. We fitted the log-log plot by the modified rounded ramp function and the slope of the oblique part was used as the fractal based descriptor. We demonstrated on histological samples of the heart that this fractal-based parameter has the property of scale and rotation invariance.
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MINETTI, Giampaolo, Claudio SEPPI, Annarita CIANA, Cesare BALDUINI, Philip S. LOW, and Augusta BROVELLI. "Characterization of the hypertonically induced tyrosine phosphorylation of erythrocyte band 3." Biochemical Journal 335, no. 2 (October 15, 1998): 305–11. http://dx.doi.org/10.1042/bj3350305.
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Human erythrocyte band 3 becomes rapidly phosphorylated on tyrosine residues after exposure of erythrocytes to hypertonic conditions. The driving force for this phosphorylation reaction seems to be a decrease in cell volume, because (1) changes in band 3 phosphotyrosine content accurately track repeated changes in erythrocyte volume through several cycles of swelling and shrinking; (2) the level of band 3 phosphorylation is independent of the osmolyte employed but strongly sensitive to the magnitude of cell shrinkage; and (3) exposure of erythrocytes to hypertonic buffers under conditions in which intracellular osmolarity increases but volume does not change (nystatin-treated cells) does not promote an increase in tyrosine phosphorylation. We hypothesize that shrinkage-induced tyrosine phosphorylation results either from an excluded-volume effect, stemming from an increase in intracellular crowding, or from changes in membrane curvature that accompany the decrease in cell volume. Although the net phosphorylation state of band 3 is shown to be due to a delicate balance between a constitutively active tyrosine phosphatase and constitutively active tyrosine kinase, the increase in phosphorylation during cell shrinkage was demonstrated to derive specifically from an activation of the latter. Further, a peculiar inhibition pattern of the volume-sensitive erythrocyte tyrosine kinase that matched that of p72syk, a tyrosine kinase already known to associate with band 3 in vivo, suggested the involvement of this kinase in the volume-dependent response.
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Hussaini, A., M. R. Mahmud, K. K. W. Tang, and A. G. Abubakar. "WATER LEVEL FLUCTUATION ASSESSMENT OF LAKE CHAD FOR ENVIRONMENTAL SUSTAINABILITY USING REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM TECHNIQUE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W16 (October 1, 2019): 261–66. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w16-261-2019.
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Abstract. Surface water is a significant constituent of the water cycle, and is paramount for human survival, social and economic development as well as environmental sustainability. Water level shrinkage and global warming are the main phenomena that becoming worldwide environmental problems. Lake Chad has been in a critical situation in recent years due to a continuous decline in surface water and drought, over abstraction of water and climate change caused a significant change of a land cover patterns. The present study aimed to highlight the change pattern of water level in the lake over the past three decades, and the satellite images of the Lake Chad from Landsat-TM, ETM+ and OLI were analyzed to investigate the change of land cover pattern during three periods: the 1985, 2000 and 2015. Supervised classification was performed for land cover change analysis. Then the overall accuracies of the classification of Landsat-TM is 93.80, Landsat-ETM+ is 90.80 and Landsat-OLI is 86.20 respectively. The result shows that there are continuous decline of water bodies, barren land and shrub, with rapid increment of farmland and gallery forest.
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Jo, Jeong Dai, Taik Min Lee, Chung Hwan Kim, Kwang Young Kim, Eung Sug Lee, and Masayoshi Esashi. "Fabrication of OTFT Array with Coated Thin Film Dielectric and Printed Electrodes by Using Microcontact Printing." Advanced Materials Research 26-28 (October 2007): 661–64. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.661.
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The gate, source, and drain electrodes of organic thin-film transistor(OTFT) to use as a switching device for a flexible display was fabricated in microcontact printing process with hard poly(dimethylsiloxane)(h-PDMS) stamp. The OTFT with thin-film dielectric layer of parylene-C(4300Å, 5000Å, 6500Å, 7500Å, and 9000Å) were formed using special coating system, and organic semiconductor layer was ink-jet printing process at room temperature. The microcontact printing process using self-assembled monolayer(SAM) and h-PDMS stamp made it possible to fabricate OTFT with channel length down to 600nm, fabricated thin film electrode of Au/Cr (100nm/5nm), and reduced the fabrication process by 20steps compared with photolithography process. Since the fabrication process was done in room temperature, there was no appeared such as pattern shrinkage, pattern transformation and bending problem.
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Ragusi, Max AA, Gonneke AO Winter-Warnars, Jelle Wesseling, Sabine C. Linn, Regina G. Beets-Tan, Bas HM van der Velden, Sjoerd G. Elias, Kenneth GA Gilhuijs, and Claudette E. Loo. "Prognostic value of breast MRI characteristics before and during neoadjuvant endocrine therapy in patients with ER+/HER2- breast cancer." British Journal of Radiology 94, no. 1123 (July 1, 2021): 20201125. http://dx.doi.org/10.1259/bjr.20201125.
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Objective: To investigate whether BIRADS MRI characteristics before or during neoadjuvant endocrine therapy (NET) are associated with the preoperative endocrine prognostic index (PEPI) in ER+/HER2- breast cancer patients. Methods: This retrospective observational cohort study included 35 ER+/HER2- patients with 38 tumors (3 bilateral cases) treated with NET. The pre- and midtreatment (after 3 months) MRIs were evaluated by two breast radiologists for BIRADS imaging characteristics, shrinkage pattern, and radiologic response. PEPI was used as end point. PEPI is based on the post-treatment surgical specimen’s pT- and pN-stage, Ki67, and ER-status. Tumors were assigned PEPI-1 (good prognosis) or PEPI-2/3 (poor prognosis). We investigated whether pre- and midtreatment BIRADS characteristics were associated with PEPI. Results: Median patient age was 65 years (interquartile interval [IQI]: 53, 70). 17 tumors (44.7%) were associated with good prognosis (PEPI-1), and 21 tumors (55.3%) with poor prognosis (PEPI-2/3). A larger reduction in tumor size after 3 months of NET was significantly associated with PEPI; 10 mm (IQI: 5, 13.5) in PEPI-1 tumors vs 4.5 mm (IQI: 3, 7; p = .045) in PEPI-2/3 tumors. Other BIRADS characteristics, shrinkage pattern or radiologic response were not associated with PEPI. Conclusion: Only a larger reduction in tumor size on MRI after 3 months of NET was associated with PEPI-1 (good prognosis) in ER+/HER2- breast cancer patients. Advances in knowledge: MRI characteristics previously reported to be associated with prognosis during neoadjuvant chemotherapy are not necessarily associated with prognosis during NET in ER+/HER2- breast cancer patients.
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Jo, Jeong Dai, Kwang Young Kim, Eung Sug Lee, and Masayoshi Esashi. "Fabrication of Organic Thin Film Transistor(OTFT) Array by Using Nanoprinting Process." Key Engineering Materials 326-328 (December 2006): 385–88. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.385.
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The flexible organic thin film transistor(OTFT) array to use as a switching device for an organic light emitting diode(OLED) was designed and fabricated in the nanocontact printing and low-temperature process. The gate, source, and drain electrode patterns of OTFT were fabricated by nanocontact printing process. And dielectric layer of parylene and organic active semiconductor layer of pentacene formed at room temperature or at a temperature lower than 40. The nanocontact printing process using SAM and PDMS stamp made it possible to fabricate OTFT arrays with channel lengths down to even submicron size, and reduced the fabrication process by 10 steps compared with photolithography. Since the process was done in room temperature, there was no pattern shrinkage, transformation, and bending problem appeared. Also, it was possible to improve electric field mobility, to decrease contact resistance, to increase close packing of molecules by SAM, and to reduce threshold voltage by using a parylene.
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Morris, G. J., G. E. Coulson, and E. A. Leeson. "Changes in the shape of mitochondria following osmotic stress to the unicellular green alga Chlamydomonas reinhardii." Journal of Cell Science 76, no. 1 (June 1, 1985): 145–53. http://dx.doi.org/10.1242/jcs.76.1.145.
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The effects of various stresses on mitochondrial activity and structure within the unicellular green alga Chlamydomonas reinhardii were investigated using the fluorescent probe rhodamine 123. Within control cells, treatment with rhodamine 123 stained an intense fluorescent network, which was considered to be mitochondrial from the similarity in structure to models of mitochondria reconstructed from serial-section electron microscopy, and because this pattern of staining was abolished following the addition of metabolic inhibitors. Following osmotic shrinkage and rehydration, fragmentation of the mitochondrial network was observed within potentially viable cells. This was reversible within 1 h of resuspension in isotonic medium. Exposure of cells to hypertonic solutions of rapidly permeating compounds did not induce similar structural alterations. These changes in the mitochondria were confirmed by thin-section electron microscopy. In the presence of higher osmolalities of non-permeating compounds, which induce a greater loss of viability, rhodamine 123 stained cells uniformly. Following the osmotic stresses induced by slow rates of freezing and subsequent thawing no fragmentation in mitochondrial staining was observed. These findings demonstrate that shrinkage and rehydration may induce alterations to the structure and function of organelles and may be factors in determining cellular viability following osmotic stress.
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Tan, Long, Penglin Zheng, and Qingbing Liu. "Effects of Saline Solutions on the Desiccation Cracking and Shrinkage Behavior of Gaomiaozi Bentonite." Advances in Civil Engineering 2020 (December 23, 2020): 1–13. http://dx.doi.org/10.1155/2020/8851838.
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Bentonite, when used as buffer/backfill material in the deep disposal of high-level radioactive waste (HLW), could undergo desiccation shrinkage or even cracking due to the heat released from HLW, impairing the efficiency of the barrier system. Furthermore, in-service buffer materials are inevitably in contact with the groundwater, which sometimes contain high salt concentrations. The groundwater salinity may modify the properties of bentonite and hence affect the process of desiccation and its performance. To investigate this effect, in this study, a series of temperature-controlled desiccation tests was conducted on compacted specimens of Gaomiaozi (GMZ) bentonite preliminarily saturated with two different saline solutions (NaCl and CaCl2) at the concentration varying from 0.5 to 2.0 mol/L. The experimental results indicated that, as the concentration of saline solution increases, the initial saturated water content of bentonite decreases, whereas the residual water content at the completion of the desiccation test increases. The water evaporation rate is reduced for the specimens saturated with a high-concentration saline solution, and CaCl2 has a more significant influence on water evaporation than NaCl. The evolution of cracks on the sample surface during the desiccation process can be divided into four stages: crack growth, maintenance, closure, and stabilization; an increase in the salt concentration effectively inhibits crack development. It was shown that the infiltration of saline solutions alters the microstructure of bentonite by changing the arrangement of clay particles from a dispersed pattern to more aggregate state, which results in a decrease in shrinkage strain and shrinkage anisotropy.
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Ebrahimi, M., Naruporn Monmaturapoj, S. Suttapreyasri, and P. Pripatnanont. "The Fabricated Collagen-Based Nano-Hydroxyapatite/β-Tricalcium Phosphate Scaffolds." Advanced Materials Research 506 (April 2012): 57–60. http://dx.doi.org/10.4028/www.scientific.net/amr.506.57.
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The biphasic calcium phosphate (BCP) concept was introduced to overcome disadvantages of single phase biomaterials. In this study, we prepared BCP from nanoHA and β-TCP that were synthesized via a solid state reaction. Three different ratios of pure BCP and collagen-based BCP scaffolds (%HA/%β-TCP; 30/70, 40/60 and 50/50) were produced using a polymeric sponge method. Physical and mechanical properties of all materials and scaffolds were investigated. XRD pattern proved the purity of each HA, β-TCP and BCP. SEM showed overall distribution of macropores (80-200 µm) with appropriate interconnected porosities. Total porosity of pure BCP (93% ± 2) was found to be higher than collagen-based BCP (85%± 3). It was observed that dimensional shrinkage of larger scaffold (39% ± 4) is lower than smaller one (42% ± 5) and scaffolds with higher HA (50%) ratio experienced greater shrinkage than those with higher β-TCP (70%) ratio (45% ±3 and 36% ±1 respectively). Mechanical properties of both groups tend to be very low and collagen coating had no influence on mechanical behavior. Further studies may improve the physical properties of these composite BCP.
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Chen, Hongyan, Mohsen Bahmani, Miha Humar, and Dali Cheng. "Properties of Wood Ceramics Prepared from Thermo-Modified Poplar." Forests 11, no. 11 (November 16, 2020): 1204. http://dx.doi.org/10.3390/f11111204.
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Wood ceramics (WCS) were prepared from thermo-modified poplar wood residues and untreated poplar wood. At 1000 °C sintering temperature, the ratios of wood powder and phenolic resin at 10:3, 10:6 and 10:9 were tested. The effects of materials on the properties of WCS, carbon yield and volume shrinkage were studied. With the increase in resin content, the carbon yield increased; however, the volume shrinkage decreased. Carbon yield of WCS made from 220 °C thermo-modified poplar wood was 40.45%, as the ratio of wood powder/phenolic resins was 10:6. The microstructure, chemical structure and crystallinity of WCS were analysed by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD), respectively. The results showed that WCS had a porous structure. WCS prepared from thermo-modified materials, amorphous carbon and hard glass carbon melted more evenly; meanwhile, there were more pores on glass carbon. The FTIR spectra showed that the stretching vibration of C-O-C weakened at ceramics made of thermo-modified poplar. The XRD pattern indicated that the raw material has no apparent influence on the graphitization degree of WCS.
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Pongratz, T., K. Siegrist, C. Burgmeier, H. D. Barth, C. G. Schmedt, and R. Sroka. "Endovenous Laser Application." Phlebologie 42, no. 03 (March 2013): 121–29. http://dx.doi.org/10.12687/phleb2134-3-2013.
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SummaryIntroduction: Endoluminal vein treatment is a promising minimal invasive treatment option for peoples suffering from varicose veins. The basic mechanism underlying this procedure is to selectively induce heat in the vessel wall with the result of denaturation of proteins and shrinkage of collagen fibers due to energy application. So far energy could be applied either as RF-current, laser light or water steam. The different approaches to deliver such forms of energies are described.Methods: Investigations on heat dependent vein tissue effects were performed. The degree of shrinkage and wall thickening due to heat induction was calculated. Tensile test on vein tissue were performed. Investigation using the radial emitting laser fibre in the ox-foot-model under reproducible condition were done and wavelengths dependent tissue reaction were explored.Results: The experiments clearly demonstrate the degree of the shrinkage of length and diameter, the thickening of the vein wall, as well as the decrease of the elasticity of the tissue. The optical irradiation pattern of the radial emitting laser fiber serves for safe and reproducible energy application directly to the vein wall. Using a laser wavelength with high absorption by the tissue water needs reduced irradiation and irradiance compared to wavelengths with less water absorption. Conclusion: An experimental approach to improve laser application for endovenous varicose treatment is described. Laser parameters and treatment parameters were found which are now under clinical testing. The demonstrated tissue effects may help to find further arguments for clinical findings and sensations described by the patients during follow-up.