Journal articles: 'Needlets'

1

Geller, Daryl, and Domenico Marinucci. "Mixed needlets." Journal of Mathematical Analysis and Applications 375, no. 2 (March 2011): 610–30. http://dx.doi.org/10.1016/j.jmaa.2010.09.046.

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Lan, Xiaohong, and Domenico Marinucci. "The needlets bispectrum." Electronic Journal of Statistics 2 (2008): 332–67. http://dx.doi.org/10.1214/08-ejs197.

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3

Baldi, P., G. Kerkyacharian, D. Marinucci, and D. Picard. "Asymptotics for spherical needlets." Annals of Statistics 37, no. 3 (June 2009): 1150–71. http://dx.doi.org/10.1214/08-aos601.

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Geller, Daryl, Xiaohong Lan, and Domenico Marinucci. "Spin needlets spectral estimation." Electronic Journal of Statistics 3 (2009): 1497–530. http://dx.doi.org/10.1214/09-ejs448.

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5

Durastanti, Claudio. "Tail behavior of Mexican needlets." Journal of Mathematical Analysis and Applications 447, no. 2 (March 2017): 716–35. http://dx.doi.org/10.1016/j.jmaa.2016.10.046.

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6

Mayeli, Azita. "Asymptotic uncorrelation for Mexican needlets." Journal of Mathematical Analysis and Applications 363, no. 1 (March 2010): 336–44. http://dx.doi.org/10.1016/j.jmaa.2009.07.044.

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7

Scodeller, S., Ø. Rudjord, F. K. Hansen, D. Marinucci, D. Geller, and A. Mayeli. "INTRODUCING MEXICAN NEEDLETS FOR CMB ANALYSIS: ISSUES FOR PRACTICAL APPLICATIONS AND COMPARISON WITH STANDARD NEEDLETS." Astrophysical Journal 733, no. 2 (May 16, 2011): 121. http://dx.doi.org/10.1088/0004-637x/733/2/121.

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Durastanti, Claudio, Yabebal T. Fantaye, Frode K. Hansen, Domenico Marinucci, and Isaac Z. Pesenson. "Radial 3D-Needlets on the Unit Ball." Proceedings of the International Astronomical Union 10, S306 (May 2014): 75–77. http://dx.doi.org/10.1017/s1743921314010801.

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AbstractWe present a simple construction of spherical wavelets for the unit ball, which we label Radial 3D Needlets. We envisage an experimental framework where data are collected on concentric spheres with the same pixelization at different radial distances from the origin. The unit ball is hence viewed as a tensor product of the unit interval with the unit sphere: a set of eigenfunctions is therefore defined on the corresponding Laplacian operator. Wavelets are then constructed by a smooth convolution of the projectors defined by these eigenfunctions. Localization properties may be rigorously shown to hold in the real and harmonic domain, and an exact reconstruction formula holds; the system allows a very convenient computational implementation.

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9

Cammarota, Valentina, and Domenico Marinucci. "On the limiting behaviour of needlets polyspectra." Annales de l'Institut Henri Poincaré, Probabilités et Statistiques 51, no. 3 (August 2015): 1159–89. http://dx.doi.org/10.1214/14-aihp609.

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Baldi, P., G. Kerkyacharian, D. Marinucci, and D. Picard. "Adaptive density estimation for directional data using needlets." Annals of Statistics 37, no. 6A (December 2009): 3362–95. http://dx.doi.org/10.1214/09-aos682.

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11

Regan, Donough, Mateja Gosenca, and David Seery. "Constraining the WMAP9 bispectrum and trispectrum with needlets." Journal of Cosmology and Astroparticle Physics 2015, no. 01 (January 9, 2015): 013. http://dx.doi.org/10.1088/1475-7516/2015/01/013.

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12

Marinucci, D., D. Pietrobon, A. Balbi, P. Baldi, P. Cabella, G. Kerkyacharian, P. Natoli, D. Picard, and N. Vittorio. "Spherical needlets for cosmic microwave background data analysis." Monthly Notices of the Royal Astronomical Society 383, no. 2 (December 10, 2007): 539–45. http://dx.doi.org/10.1111/j.1365-2966.2007.12550.x.

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13

Kerkyacharian, Gérard, George Kyriazis, Erwan Le Pennec, Pencho Petrushev, and Dominique Picard. "Inversion of noisy Radon transform by SVD based needlets." Applied and Computational Harmonic Analysis 28, no. 1 (January 2010): 24–45. http://dx.doi.org/10.1016/j.acha.2009.06.001.

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Yan, Hao, Owen Carmichael, Debashis Paul, and Jie Peng. "Estimating fiber orientation distribution from diffusion MRI with spherical needlets." Medical Image Analysis 46 (May 2018): 57–72. http://dx.doi.org/10.1016/j.media.2018.01.003.

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15

Kueh, A. "Locally Adaptive Density Estimation on the Unit Sphere Using Needlets." Constructive Approximation 36, no. 3 (May 16, 2012): 433–58. http://dx.doi.org/10.1007/s00365-012-9170-2.

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16

Faÿ, Gilles, and Frédéric Guilloux. "Spectral estimation on the sphere with needlets: high frequency asymptotics." Statistical Inference for Stochastic Processes 14, no. 1 (January 18, 2011): 47–71. http://dx.doi.org/10.1007/s11203-010-9050-y.

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17

Faÿ, Gilles, Jacques Delabrouille, Gérard Kerkyacharian, and Dominique Picard. "Testing the isotropy of high energy cosmic rays using spherical needlets." Annals of Applied Statistics 7, no. 2 (June 2013): 1040–73. http://dx.doi.org/10.1214/12-aoas619.

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Remazeilles, Mathieu, Nabila Aghanim, and Marian Douspis. "Reconstruction of high-resolution Sunyaev–Zeldovich maps from heterogeneous data sets using needlets." Monthly Notices of the Royal Astronomical Society 430, no. 1 (January 22, 2013): 370–85. http://dx.doi.org/10.1093/mnras/sts636.

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19

Scodeller, Sandro, Frode K. Hansen, and Domenico Marinucci. "DETECTION OF NEW POINT SOURCES INWMAP7 YEAR DATA USING INTERNAL TEMPLATES AND NEEDLETS." Astrophysical Journal 753, no. 1 (June 12, 2012): 27. http://dx.doi.org/10.1088/0004-637x/753/1/27.

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20

Ivanov, Kamen G., and Pencho Petrushev. "Fast and accurate evaluation of geomagnetic field elements at arbitrary points in space." Geophysical Journal International 224, no. 1 (September 18, 2020): 181–90. http://dx.doi.org/10.1093/gji/ggaa439.

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SUMMARY An algorithm and software are developed for fast and accurate evaluation of the elements of the geomagnetic field represented in high-degree (>720) solid spherical harmonics at many scattered points in the space above the surface of the Earth. The algorithm is based on representation of the geomagnetic field elements in solid ellipsoidal harmonics and application of tensor product needlets. Open source FORTRAN and MATLAB realizations of this algorithm that rely on data from the Enhanced Magnetic Models 2015, 2017 (EMM2015, EMM2017) have been developed and extensively tested. The capabilities of the software are demonstrated on the example of the north, east and down components of the geomagnetic field as well as the derived horizontal intensity, total intensity, inclination and declination. For the range from −417 m under the Earth reference ellipsoid up to 1000 km above it the FORTRAN and MATLAB versions of the software run 465 and 189 times faster than the respective FORTRAN and MATLAB versions of the software using the standard spherical harmonic series method, while the accuracy is less than 1 nT and the memory (RAM) usage is 9 GB.

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21

Mashroteh, Hasan, and Mohammad Zarrebini. "Multivariate Regression Modeling of Parameters Affecting Punching Force during Random Velour Needling." Journal of Engineered Fibers and Fabrics 10, no. 2 (June 2015): 155892501501000. http://dx.doi.org/10.1177/155892501501000211.

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Manufacturing of random velour needled fabrics comprises two separate needling operations. In the first stage a carded fibrous assembly is consolidated using a barbed needle. The consolidated assembly is opened-up due to action of fork needles of the second needling stage. In this special needling operation the mono-structure consolidated fibrous assembly is converted to a bi-structure fibrous assembly, comprised of base and pile layers. The extent of imparted structural changes influences physical and mechanical properties of the resultant random velour fabric. Fork needles which are the culprit of the structural alteration are subjected to relatively large forces. In this work the effect of random velour needling parameters and fiber characteristics on force exerted on the fork needle were investigated. Force measurement and data analysis were carried out using a purposely designed twin load cell force measuring unit and required software. Sixty four samples of polyester fabrics were prepared. Separate identification of the effect of principle independent parameters on the exerted force on individual fork needles was achieved using a linear multivariate regression analysis based on SAS 9.1 statistical software. Estimation of total average force (Frms) and peak average force (FPA) were used as response variables of the model. Results manifested that force exerted on the fork needle is profoundly affected by a large number of parameters. It was also found that, total fiber displacement “ TFD“, occurring during random-velour needling was the foremost factor directly influencing force on the fork needles.

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22

Babović, Miloš, and Vukota Babović. "How needless are Buffon's needles?" European Journal of Physics 34, no. 3 (April 2, 2013): 715–28. http://dx.doi.org/10.1088/0143-0807/34/3/715.

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23

Seyam, Abdelfattah M., and Siddartha Sarin. "Effect of Needle Position and Orientation on Forces Experienced by Individual Needles during Needle Punching." Textile Research Journal 67, no. 10 (October 1997): 772–76. http://dx.doi.org/10.1177/004051759706701011.

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Needle force is measured on felting needles at four different locations simultaneously using four mini-transducers mounted on the needle board of a James Hunter 12 inch model loom. The machine speed is 300 strokes/minute, needling density is 34.6 punches/cm2, and the depth of penetration is 16 mm. Results indicate that differences in the needling force between needles of the same type and needle location in the needle board are significant. Needle force is also significantly greater at the back of the needle board where the needles penetrate fresh web, compared to the front of the needle board. An absence of needles surrounding the test needles causes the test needles to experience significantly greater force.

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Bawor-Omatseye, A., and A. Majumdar. "Needless needle loss." British Dental Journal 215, no. 4 (August 2013): 153–54. http://dx.doi.org/10.1038/sj.bdj.2013.795.

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25

Liang, Yu Dan, and Xiu Hua Chen. "The Progress of Advanced Engineering Materials in Acupuncture Needle." Key Engineering Materials 723 (December 2016): 277–81. http://dx.doi.org/10.4028/www.scientific.net/kem.723.277.

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In order to promote the development of acupuncture technique and improve the effect of acupuncture, acupuncturists have innovated and produced many new acupuncture needles using suitable engineering materials. This article aims to show the progress of advance engineering materials in acupuncture needles. We searched the international database PubMed, EI, and the Chinese database CNKI, Wangfang. The MESH and Key words were: acupuncture needle, needle implement, acupuncture implement, float needle, new nine needles, fire needle, laser acupuncture. And we classified the new needles into 5 related parts: name, inventor, function, materials and application. In this study, we had summarized common used 13 needles and 15 materials. The mainly used needles were Stone Needle, Metal needle, Stainless steel needle, New nine needles, Magnetic pole needle and Floating-Acupuncture. The mainly used materials were Si Bin floating stone, stainless steel, magnet, molybdenum, tungsten .Stainless steel needle is the most frequently used in clinic. In conclusion, there are not many advance engineering materials applied in acupuncture needles. A few materials help to promote the development of acupuncture but they are not frequently used enough. The development of acupuncture needs more suitable materials to improve the function of needle. An ideal needle may be painless but thicker enough to manipulate, and produce some material effect to produce enough stimulating quantity.

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26

English, Judith Fay Boylan. "Reported Hospital Needlestick Injuries in Relation to Knowledge/Skill, Design, and Management Problems." Infection Control & Hospital Epidemiology 13, no. 5 (May 1992): 259–64. http://dx.doi.org/10.1086/646524.

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AbstractObjectives:To investigate reported needlestick injuries in hospital workers from an adult learner theory perspective: identifying safe needle device knowledge and practice, and flaws in needle designs and management practices surrounding such problems.Design:Exploratory descriptive study of reported needlestick injuries from hollow needled devices in a hospital. Injured healthcare workers were counseled via hospital protocol, then a survey was filled out containing no identifiers of individual or institution.Setting:Seventeen Metropolitan Washington, DC, area hospitals.Participants:All workers reporting needlestick injuries during February 1-28, 1990.Results:Seventy-two injuries were reported; there were no multiple injuries to any individual. Thirty-three (45.8%) were to registered nurses (RNs)-more than any other group of workers. Recapping accounted for a higher percentage than any other activity (10 sticks, 14.1%). Of workers incurring recapping injuries, 3 identified a knowledge of a one-handed spearing technique and did not practice it; 4 neither knew nor practiced it. Eighteen (25.0%) were to “down-stream” housekeepers and aides who did not use such devices in their practice. Disposable needle/syringes caused 49.3% of injuries; hypodermic needles on intravenous lines caused 16.9%. Of the needlesticks, 60.6% were after use and before disposal, 4.2% occurred as the worker was putting an item into a needlebox, and 9.9% occurred from needles protruding from inappropriate bags. Many injuries occurred in the first 2 hours of work after being off the previous day, on Sunday, and on MondayConclusions:Of nurses and medical technologists reporting knowledge of a spearing recapping technique, 97.3% suffered injury via other methods. This strongly suggests that knowledge leads to different action. Safer needled devices and needle-free systems would make a safer workplace. Further study is indicated to identify if and why the first two hours after returning to work on Sunday or Monday are risky for needlestick injuries. Management practices must ensure compliance to safe practice both by employees and related medical staff.

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27

Li, Zihao, Shuang Song, Li Liu, and Max Q. H. Meng. "Tip Estimation Method in Phantoms for Curved Needle Using 2D Transverse Ultrasound Images." Applied Sciences 9, no. 24 (December 5, 2019): 5305. http://dx.doi.org/10.3390/app9245305.

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Flexible needles have been widely used in minimally invasive surgeries, especially in percutaneous interventions. Among the interventions, tip position of the curved needle is very important, since it directly affects the success of the surgeries. In this paper, we present a method to estimate the tip position of a long-curved needle by using 2D transverse ultrasound images from a robotic ultrasound system. Ultrasound is first used to detect the cross section of long-flexible needle. A new imaging approach is proposed based on the selection of numbers of pixels with a higher gray level, which can directly remove the lower gray level to highlight the needle. After that, the needle shape tracking method is proposed by combining the image processing with the Kalman filter by using 3D needle positions, which develop a robust needle tracking procedure from 1 mm to 8 mm scan intervals. Shape reconstruction is then achieved using the curve fitting method. Finally, the needle tip position is estimated based on the curve fitting result. Experimental results showed that the estimation error of tip position is less than 1 mm within 4 mm scan intervals. The advantage of the proposed method is that the shape and tip position can be estimated through scanning the needle’s cross sections at intervals along the direction of needle insertion without detecting the tip.

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28

Matheson, Eloise, Riccardo Secoli, Christopher Burrows, Alexander Leibinger, and Ferdinando Rodriguez y Baena. "Cyclic Motion Control for Programmable Bevel-Tip Needles to Reduce Tissue Deformation." Journal of Medical Robotics Research 04, no. 01 (March 2019): 1842001. http://dx.doi.org/10.1142/s2424905x18420011.

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Robotic-assisted steered needles aim to accurately control the deflection of the flexible needle’s tip to achieve accurate path following. In doing so, they can decrease trauma to the patient, by avoiding sensitive regions while increasing placement accuracy. This class of needle presents more complicated kinematics compared to straight needles, which can be exploited to produce specific motion profiles via careful controller design and tuning. Motion profiles can be optimized to minimize certain conditions such as maximum tissue deformation and target migration, which was the goal of the formalized cyclic, low-level controller for a Programmable Bevel-tip Needle (PBN) presented in this work. PBNs are composed of a number of interlocked segments that are able to slide with respect to one another. Producing a controlled, desired offset of the tip geometry leads to the corresponding desired curvature of the PBN, and hence desired path trajectory of the system. Here, we propose a cyclical actuation strategy, where the tip configuration is achieved over a number of reciprocal motion cycles, which we hypothesize will reduce tissue deformation during the insertion process. A series of in vitro, planar needle insertion experiments are performed in order to compare the cyclic controller performance with the previously used direct push controller, in terms of targeting accuracy and tissue deformation. It is found that there is no significant difference between the target tracking performance of the controllers, but a significant decrease in axial tissue deformation when using the cyclic controller.

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Han, Samuel, Furqan Bhullar, Omar Alaber, Ayesha Kamal, Puanani Hopson, Kavin Kanthasamy, Sarah Coughlin, et al. "Comparative diagnostic accuracy of EUS needles in solid pancreatic masses: a network meta-analysis." Endoscopy International Open 09, no. 06 (May 27, 2021): E853—E862. http://dx.doi.org/10.1055/a-1381-7301.

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Abstract Background and study aims Endoscopic ultrasound (EUS)-guided tissue sampling is the standard of care for diagnosing solid pancreatic lesions. While many two-way comparisons between needle types have been made in randomized controlled trials (RCTs), it is unclear which size and type of needle offers the best probability of diagnosis. We therefore performed a network meta-analysis (NMA) to compare different sized and shaped needles to rank the diagnostic performance of each needle. Methods We searched MEDLINE, EMBASE and Cochrane Library databases through August, 2020 for RCTs that compared the diagnostic accuracy of EUS fine-needle aspiration (FNA) and biopsy (FNB) needles in solid pancreatic masses. Using a random-effects NMA under the frequentist framework, RCTs were analyzed to identify the best needle type and sampling technique. Performance scores (P-scores) were used to rank the different needles based on pooled diagnostic accuracy. The NMA model was used to calculate pairwise relative risk (RR) with 95 % confidence intervals. Results Review of 2577 studies yielded 29 RCTs for quantitative synthesis, comparing 13 different needle types. All 22G FNB needles had an RR > 1 compared to the reference 22G FNA (Cook) needle. The highest P-scores were seen with the 22G Medtronic FNB needle (0.9279), followed by the 22G Olympus FNB needle (0.8962) and the 22G Boston Scientific FNB needle (0.8739). Diagnostic accuracy was not significantly different between needles with or without suction. Conclusions In comparison to FNA needles, FNB needles offer the highest diagnostic performance in sampling pancreatic masses, particularly with 22G FNB needles.

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Boroomand, Arefeh, Mahdi Tavakoli, Ron Sloboda, and Nawaid Usmani. "Dynamical modeling and controllability analysis of a flexible needle in soft tissue." International Journal of Modeling, Simulation, and Scientific Computing 05, no. 02 (February 25, 2014): 1350031. http://dx.doi.org/10.1142/s1793962313500311.

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This paper is concerned with deriving a dynamic model of a moderately flexible needle inserted into soft tissue, where the model's output is the needle deflection. The main advantages of the proposed dynamic modeling approach are that the presented model structure involves parameters that are all measurable or identifiable by simple experiments and that it considers the same inputs that are currently used in the clinical practice of manual needle insertion. Conventional manual needle insertion suffers from the fact that flexible needles bend during insertion and their trajectories often vary from those planned, resulting in positioning errors. Enhancement of needle insertion accuracy via robot-assisted needle steering has received significant attention in the past decade. A common assumption in previous research has been that the needle behavior during insertion can be adequately described by static models relating the needle's forces and torques to its deflection. For closed-loop control purposes, however, a dynamic model of the flexible needle in soft tissue is desired. In this paper, we propose a Lagrangian-based dynamic model for the coupled needle/tissue system, and analyze the response of the dynamic system. Steerability (controllability) analysis is also performed, which is only possible with a dynamic model. The proposed dynamic model can serve as a cornerstone of future research into designing dynamics-based control strategies for closed-loop needle steering in soft tissue aimed at minimizing position error.

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Hayhoe, Simon, Maria McCrossan, Aden Smith, David Ellis, Simon Croft, and Man Fong Mei. "Single-Use Acupuncture Needles: Scanning Electron-Microscopy of Needle-Tips." Acupuncture in Medicine 20, no. 1 (March 2002): 11–18. http://dx.doi.org/10.1136/aim.20.1.11.

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Unselected, disposable acupuncture needles from various manufacturers and retail suppliers were taken from a pool of donated and bought samples. Three needles of each type were prepared for electron-microscopy. The needle tips were inspected at two magnifications (x39.37 and x612.5): 52 electron-micrographs were taken of 31 individual needles from 11 different types. No needle-tip looked perfect and significant faults were seen in most; some appeared seriously deformed. The faults noted were: scratch marks along or across the needle, metallic scuff, lumps and irregularities in the needle surface, needle-tip stubbed or malformed, and needle point off-centre. An additional test made was to wipe a number of needles firmly on white paper tissue. Some left grey lines, and these were regarded as evidence of metallic or oily residue from the needle surface which could have been deposited in the patient. These unexpected findings, in a variety of popularly used needles from well-respected suppliers, suggest that most manufacturers need to reassess their quality control procedures.

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Deam, R. K., R. Kluger, J. Barrington, and C. A. McCutcheon. "Investigation of a New Echogenic Needle for use with Ultrasound Peripheral Nerve Blocks." Anaesthesia and Intensive Care 35, no. 4 (August 2007): 582–86. http://dx.doi.org/10.1177/0310057x0703500419.

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A new ‘texturing method’ has been developed for nerve block needles in an attempt to improve the ultrasonic image of the needles. Using a synthetic phantom, these textured needles were compared to currently available needles. The textured needle had improved visibility under ultrasound. This type of needle may assist the anaesthetist perform ultrasound-guided regional anaesthesia.

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Dong, YiJie, LiLi Gao, Yang Sui, MinJing Mao, WeiWei Zhan, and JianQiao Zhou. "Comparison of Ultrasound-Guided Fine-Needle Cytology Quality in Thyroid Nodules with 22-, 23-, and 25-Gauge Needles." Analytical Cellular Pathology 2021 (June 7, 2021): 1–7. http://dx.doi.org/10.1155/2021/5544921.

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Objective. To compare the cytology quality of ultrasound-guided fine-needle biopsy in thyroid nodules with 22-, 23-, and 25-gauge (G) needles prospectively. Methods. A total of 240 consecutive nodules underwent ultrasound-guided fine-needle aspiration (USG-FNA) and 240 nodules underwent ultrasound-guided fine-needle capillary (USG-FNC) were included in this prospective study from October 2014 to February 2016. Each nodule was sampled using 22 G, 23 G, and 25 G needle according to designed orders, and 1240 smears were finally obtained. Cytology quality was scored by a cytologist blinded to needle selection. Results. In USG-FNA, the average scores and standard deviations were 5.50 ± 2.87 for 25 G needles, 4.82 ± 2.95 for 23 G needles, and 5.19 ± 2.81 for 22 G needles. In USG-FNC, the average scores and standard deviations of each group were 5.12 ± 2.69 for 25 G, 4.60 ± 2.90 for 23 G, and 4.90 ± 2.90 for 22 G needles. The specimen quality scores of 25 G group were significantly higher than that of 23 G group ( P < 0.017 ) in both USG-FNA and USG-FNC. However, the differences were not statistically significant in nondiagnostic rate using different gauge of needles ( P > 0.017 for all). Conclusions. 25 G needles obtained the highest scores of sample quality in thyroid FNA and FNC comparing with 22 G and 23 G needles. 25 G needle should be first choice of thyroid FNA and FNC in routine work.

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Hata, Kunihiko, Kazuyoshi Futai, and Mitsuya Tsuda. "Seasonal and needle age-dependent changes of the endophytic mycobiota in Pinus thunbergii and Pinus densiflora needles." Canadian Journal of Botany 76, no. 2 (February 1, 1998): 245–50. http://dx.doi.org/10.1139/b97-177.

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Monthly changes in the endophytic mycobiota in Pinus thunbergii Parl. and Pinus densiflora Sieb. et Zucc. needles were detected by tissue culture. Endophytic mycobiota of these pine needles were dominated by four taxa: the Leptostroma anamorph of the Lophodermium pinastri (Schrad. ex Hook.) Chev. complex, Phialocephala sp., Cenangium ferruginosum Fr.:Fr., and an unidentified hyphomycete species (BrS). The mycobiota differed with host pine species, position on the needle, and needle age. Virtually no endophytes were detected in needles just after emergence, but most segments of the older needles harbored endophytes. The endophytic mycobiota changed slowly with needle aging, except for the periods of rapid increase in the detection frequency of Leptostroma and Phialocephala sp. Detection frequency of Leptostroma, the most frequently detected endophyte taxon in the needles of the two pine species, continuously increased with needle aging, while that of Phialocephala sp., the endophyte mainly detected from the basal segments of Pinus densiflora, slowly decreased with needle aging after a massive emergence in current-year needles.Key words: Pinus thunbergii, Pinus densiflora, pine needle, endophytic fungi.

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N, Saifuddin Kusuma, Fonny Dahong, and Muh Ruslin. "Penatalaksanaan patah jarum akibat anastesi lokal pada ekstraksi gigi Management of broken needle cause by local anesthesia on teeth extraction." Journal of Dentomaxillofacial Science 11, no. 3 (October 30, 2012): 192. http://dx.doi.org/10.15562/jdmfs.v11i3.337.

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Since the inroduction of disposable needles, breakage of needles within tissues have become extremely rare.However, reports of needle breakage still appear. This paper discussed the cause of needle breakage, problem ofneedle breakage, prevention of needle breakage, and management of needle breakage. If the needle broken duringanesthesia of the alveolar dental nerve process, the needle will probably be located in the pterygomandibular space.It can migrate to vital structure.

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Stone, Jeffrey K. "Initiation and development of latent infections by Rhabdocline parkeri on Douglas-fir." Canadian Journal of Botany 65, no. 12 (December 1, 1987): 2614–21. http://dx.doi.org/10.1139/b87-352.

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Quantitative estimates of frequencies of latent infections by Rhabdocline parkeri Sherw. on Douglas-fir were obtained by direct microscopy of cleared needles from three half-sib trees. The infections are intracellular and are confined to a single epidermal cell until the onset of needle senescence, a period of 2 – 5 years. Infection frequencies varied widely among trees but increase logarithmically with needle age on all three trees. Differences in infection frequencies among trees were not demonstrably related to levels of infestation by Contarinia spp., a needle-galling dipteran. Active colonization of the needle resumes at the onset of needle senescence, beginning with the production of haustoria in cells adjacent to the original infection sites. Rapid colonization of the needle and sporulation of R. parkeri coincide with needle abscission, occurring before substantial colonization of the needles by saprophytic fungi. Saprophytic fungi colonized needles rapidly following abscission, but R. parkeri was recoverable in culture from needles up to 35 days after abscission.

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Takakura, Nobuari, Miho Takayama, Akiko Kawase, Ted J. Kaptchuk, and Hiroyoshi Yajima. "Double Blinding with a New Placebo Needle: A Further Validation Study." Acupuncture in Medicine 28, no. 3 (September 2010): 144–48. http://dx.doi.org/10.1136/aim.2009.001230.

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Background The masking properties of a new, non-penetrating, double-blind placebo acupuncture needle were demonstrated. Practitioners correctly identified some of the needles; if they were confident in this opinion, they would be unblinded. Objective To investigate the clues that led to correct identification, and the confidence in this decision. Methods Ten acupuncture practitioners, blindly and randomly, applied 10 each of three types of needle to the shoulder: blunt, non-penetrating needles that pressed the skin (‘skin-touch placebo needle’); new non-penetrating needles that penetrated soft material (stuffing) but did not reach the skin (‘non-touch control needle’); matching penetrating needles. Afterwards, practitioners were asked to judge the type of needle, their confidence in their decision and what clues led them to their judgements. Results Of the 30 judgements made by each practitioner, the mean number of correct, incorrect and unidentifiable answers were 10.4 (SD 3.7), 15.2 (SD 4.9) and 4.4 (SD 6.1), respectively. There was no significant difference in the confidence scores for 104 correct (mean, 54.0 (SD 20.2)%) and 152 incorrect (mean, 50.3 (SD 24.3)%) judgements. Twelve needles were identified with 100% confidence—three correct, and nine incorrect. For needles correctly identified, the proportions of non-touch (p = 0.14) and skin-touch (p = 0.17), needles were no greater than chance, but the proportion of penetrating needles correctly identified exceeded chance (p < 0.01). 53% of judgements were made from the “feeling of needle insertion”, but 57% of these were wrong. Conclusion Practitioners had a slight tendency to guess the penetrating needles correctly, but were uncertain about most of their judgments, posing only a very small risk to double blinding.

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Mei, Ling, Xiaojing Long, Yanjun Diao, Haibo Yu, Wanzhang Yang, Leanna J. Standish, and Bensheng Qiu. "Mri Evaluation of Metal Acupuncture Needles." Acupuncture in Medicine 31, no. 4 (December 2013): 404–8. http://dx.doi.org/10.1136/acupmed-2013-010392.

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Objective To evaluate the MR compatibility of three metal acupuncture needles (a standard stainless steel needle, a gold needle and an austenitic stainless steel needle) by comparing their imaging artefacts, radiofrequency heating effects and ease of operation. Methods The MRI artefacts of the three metal needles were first evaluated by placing them in an agar gel phantom and performing MRI of the phantom. The increase in temperature during MRI was recorded using an MR-compatible fibreoptic thermometer. MRI of acupuncture at SP6 was performed using the MR-compatible gold needle and the austenitic stainless steel needle. Results The standard stainless steel acupuncture needle produced large imaging artefacts on MRI. The gold needle was superior for MRI but not rigid enough for some clinical applications such as scalp acupuncture. The austenitic stainless steel needle is non-ferromagnetic and compatible with MRI. None of these acupuncture needles introduced radiofrequency heating during MRI. Conclusions The evaluation of MR compatibility showed that gold and austenitic stainless steel needles are MR-compatible and therefore can be used for MRI of acupuncture.

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Tuka, Vladimir, Edwin Wijnen, Frank M. van der Sande, and Jan Hm Tordoir. "Dialysis Needle Hemodynamics in Arterio-Venous Fistulae: A Technical Report." Journal of Vascular Access 10, no. 3 (July 2009): 157–59. http://dx.doi.org/10.1177/112972980901000304.

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Background Vascular access is the lifeline for end-stage renal disease patients needing hemodialysis treatment. For dialysis treatment two needles are placed into the vascular access. Few studies on needle hemodynamics have been published. Methods We investigated needle hemodynamics by means of Doppler ultrasonography, both in B-mode and in pulsed Doppler mode. Results Direct visualization of the needles, turbulence around the arterial needle and blood flow jet from the venous needle are presented. Conclusions Ultrasound investigation of the hemodynamics of the dialysis needles is feasible. The extreme blood flow jet through the arterial needle was directed in all patients to the anterior vessel wall.

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Xu, Yingqiang, Xuemei Qin, Guowei Liu, Lei Tan, Hongjian Dong, Pengpeng Wei, Qinhe Zhang, and Hongcai Zhang. "A new method for evaluating the normal rake angle and inclination angle on medical needles." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 232, no. 1 (November 22, 2017): 24–32. http://dx.doi.org/10.1177/0954411917742942.

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Hollow needles are the most frequently used medical equipment. The design of a hollow needle that best enables medical procedures requires a better understanding of needle tip geometry. Calculating the cutting angles of a needle for a complex surface topology is difficult. This article proposes a new method based on non-Euclidean geometry for the analysis of biopsy needle tip. The method can be used to calculate the cutting angles on any pipe needle. To verify the validity of this method, the normal rake angle and inclination angle on four types of needles (bias bevel needle, cylinder surface needle, curved surface needle and Cournand-type needle) were investigated. It was found that calculation of the cutting angles was simple and convenient using this method, especially for the curved surface needles. Images of the cutting angles from the Cournand-type needles revealed that the smaller bevel angle [Formula: see text] resulted in a higher normal rake angle [Formula: see text] and inclination angle [Formula: see text]. As [Formula: see text] increased, the range of the normal rake angle [Formula: see text] became larger at first and then became smaller.

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Leonard, Laura T., Kristin Mikkelson, Zhao Hao, Eoin L. Brodie, Kenneth H. Williams, and Jonathan O. Sharp. "A comparison of lodgepole and spruce needle chemistry impacts on terrestrial biogeochemical processes during isolated decomposition." PeerJ 8 (July 16, 2020): e9538. http://dx.doi.org/10.7717/peerj.9538.

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This study investigates the isolated decomposition of spruce and lodgepole conifer needles to enhance our understanding of how needle litter impacts near-surface terrestrial biogeochemical processes. Harvested needles were exported to a subalpine meadow to enable a discrete analysis of the decomposition processes over 2 years. Initial chemistry revealed the lodgepole needles to be less recalcitrant with a lower carbon to nitrogen (C:N) ratio. Total C and N fundamentally shifted within needle species over time with decreased C:N ratios for spruce and increased ratios for lodgepole. Differences in chemistry correlated with CO2 production and soil microbial communities. The most pronounced trends were associated with lodgepole needles in comparison to the spruce and needle-free controls. Increased organic carbon and nitrogen concentrations associated with needle presence in soil extractions further corroborate the results with clear biogeochemical signatures in association with needle chemistry. Interestingly, no clear differentiation was observed as a function of bark beetle impacted spruce needles vs those derived from healthy spruce trees despite initial differences in needle chemistry. These results reveal that the inherent chemistry associated with tree species has a greater impact on soil biogeochemical signatures during isolated needle decomposition. By extension, biogeochemical shifts associated with bark beetle infestation are likely driven more by changes such as the cessation of rhizospheric processes than by needle litter decomposition.

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Prince, Jeffrey S. "Raphides in the Uncalcified Siphonous Green Seaweed,Codium minus(Schmidt) P. C. Silva." Journal of Marine Biology 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/382498.

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The vacuole of utricles, the outermost cell layer of the siphonous green seaweed,Codium minus, had numerous single needles and needle bundles. The crystals composing each needle appeared arranged in a twisted configuration, both ends were pointed, and each needle was contained in a matrix or membrane; bundles of needles appeared enclosed by a matrix. Chemical and electron diffraction analysis indicated that the needles consisted of calcium oxalate. This is the first paper on terrestrial plant-like raphides in an alga.

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Lin, Jinxing, D. A. Sampson, G. Deckmyn, and R. Ceulemans. "Significant overestimation of needle surface area estimates based on needle dimensions in Scots pine (Pinus sylvestris)." Canadian Journal of Botany 80, no. 9 (September 1, 2002): 927–32. http://dx.doi.org/10.1139/b02-081.

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Needle length and width at midpoint are often used to make estimates of needle surface area for conifers. For these estimates, Scots pine (Pinus sylvestris L.) fascicles are assumed to be cylindrical; thus, for a two-needle pine, the cross section of a needle within the fascicle is assumed to be hemicylindrical. The objectives of this study were to determine whether these assumptions lead to a good estimate of the actual surface area and how needles vary with tree age and crown position. We used a digital scanning microscope to measure needle width, thickness, and perimeter at 11 positions along 28 needles from different crown positions in different-aged trees and found that they varied with position within the individual needle as well as with tree age and crown position. Needle shape was relatively constant: needle width and perimeter both increased from the base to the needle midpoint and then decreased slightly to the needle tip, but needles were not hemicylindrical and actual perimeters were nearly 12% larger than predicted perimeters. The predicted surface areas based on measurements of width at the needle midpoint and length need to be reduced by 9% to account for the fact that needles taper and are not cylindrical. Furthermore, tree age and crown position must be considered when crown-level estimates are made.Key words: digital image analyzer, light microscope, needle width, needle thickness, needle perimeter, Pinus sylvestris.

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Polkowski, Marcin, Christian Jenssen, Philip Kaye, Silvia Carrara, Pierre Deprez, Angels Gines, Gloria Fernández-Esparrach, et al. "Technical aspects of endoscopic ultrasound (EUS)-guided sampling in gastroenterology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Guideline – March 2017." Endoscopy 49, no. 10 (September 12, 2017): 989–1006. http://dx.doi.org/10.1055/s-0043-119219.

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RECOMMENDATIONSFor routine EUS-guided sampling of solid masses and lymph nodes (LNs) ESGE recommends 25G or 22G needles (high quality evidence, strong recommendation); fine needle aspiration (FNA) and fine needle biopsy (FNB) needles are equally recommended (high quality evidence, strong recommendation).When the primary aim of sampling is to obtain a core tissue specimen, ESGE suggests using 19G FNA or FNB needles or 22G FNB needles (low quality evidence, weak recommendation).ESGE recommends using 10-mL syringe suction for EUS-guided sampling of solid masses and LNs with 25G or 22G FNA needles (high quality evidence, strong recommendation) and other types of needles (low quality evidence, weak recommendation). ESGE suggests neutralizing residual negative pressure in the needle before withdrawing the needle from the target lesion (moderate quality evidence, weak recommendation).ESGE does not recommend for or against using the needle stylet for EUS-guided sampling of solid masses and LNs with FNA needles (high quality evidence, strong recommendation) and suggests using the needle stylet for EUS-guided sampling with FNB needles (low quality evidence, weak recommendation).ESGE suggests fanning the needle throughout the lesion when sampling solid masses and LNs (moderate quality evidence, weak recommendation).ESGE equally recommends EUS-guided sampling with or without on-site cytologic evaluation (moderate quality evidence, strong recommendation). When on-site cytologic evaluation is unavailable, ESGE suggests performance of three to four needle passes with an FNA needle or two to three passes with an FNB needle (low quality evidence, weak recommendation).For diagnostic sampling of pancreatic cystic lesions without a solid component, ESGE suggests emptying the cyst with a single pass of a 22G or 19G needle (low quality evidence, weak recommendation). For pancreatic cystic lesions with a solid component, ESGE suggests sampling of the solid component using the same technique as in the case of other solid lesions (low quality evidence, weak recommendation).ESGE does not recommend antibiotic prophylaxis for EUS-guided sampling of solid masses or LNs (low quality evidence, strong recommendation), and suggests antibiotic prophylaxis with fluoroquinolones or beta-lactam antibiotics for EUS-guided sampling of cystic lesions (low quality evidence, weak recommendation). ESGE suggests that evaluation of tissue obtained by EUS-guided sampling should include histologic preparations (e. g., cell blocks and/or formalin-fixed and paraffin-embedded tissue fragments) and should not be limited to smear cytology (low quality evidence, weak recommendation).

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Adami, Chiara, Alessandra Bergadano, and Claudia Spadavecchia. "Limitations of the Use of Pressure Waves to Verify Correct Epidural Needle Position in Dogs." Veterinary Medicine International 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/159489.

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The use of pressure waves to confirm the correct position of the epidural needle has been described in several domestic species and proposed as a valid alternative to standard methods, namely, control radiographic exam and fluoroscopy. The object of this retrospective clinical study was to evaluate the sensitivity of the epidural pressure waves as a test to verify the correct needle placement in the epidural space in dogs, in order to determine whether this technique could be useful not only in the clinical setting but also when certain knowledge of needle’s tip position is required, for instance when performing clinical research focusing on epidural anaesthesia. Of the 54 client-owned dogs undergoing elective surgeries and enrolled in this retrospective study, only 45% showed epidural pressure waves before and after epidural injection. Twenty-six percent of the animals showed epidural pressure waves only after the injection, whereas 29% of the dogs showed epidural pressure waves neither before nor after injection and were defined as false negatives. Our results show that the epidural pressure wave technique to verify epidural needle position lacks sensitivity, resulting in many false negatives. As a consequence, the applicability of this technique is limited to situations in which precise, exact knowledge of the needle's tip position is not mandatory.

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Deng, Weimin, and Randolph M. Beaudry. "Overcoming Gas Sampling Problems: Analysis of Volatiles Using Capillary Column Needles." HortScience 31, no. 4 (August 1996): 643f—643. http://dx.doi.org/10.21273/hortsci.31.4.643f.

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Sampling factors that could affect gas chromatograph (GC) response for volatile analysis such as syringe pumping time, injection volume, needle length, temperature, and the type of volatile were investigated. Capillary GC column segments (steel and glass) were installed in gas-tight syringes and used as needles for volatile analysis. Standard stainless-steel needles were also used. Hexylacetate, ethyl-2-methylbutyrate, 6-methyl-5-hepten-2-one, and butanol standard were measured. The number of pumps required to maximize GC response for each needle–volatile combination was determined. Maximal GC response for hexylacetate using standard stainless steel, capillary glass, and capillary steel needles required 10, 20 and 30 pumps, respectively. However, for butanol measurement, the optimal syringe pump number was 5 to 10 for all needle types. The use of a capillary needle resulted in an increase in GC response in the range of 3- to 15-fold relative to a standard stainless steel needle. Injection volume affected GC response in a needle-and volatile-dependent manner. In no case did injection volume vs. GC response extrapolate through origin. The GC response for capillary column needles increased as temperature decreased. Capillary column needles may be useful tools for analysis of volatiles that readily partition into the column coating.

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Percy, K. E., R. Jagels, S. Marden, C. K. McLaughlin, and J. Carlisle. "Quantity, chemistry, and wettability of epicuticular waxes on needles of red spruce along a fog-acidity gradient." Canadian Journal of Forest Research 23, no. 7 (July 1, 1993): 1472–79. http://dx.doi.org/10.1139/x93-184.

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Needle wettability and epicuticular wax physicochemical characteristics were examined for red spruce (Picearubens Sarg.) trees growing along a gradient of fog quantity and acidity. Trees at four coastal and one inland site were sampled in November 1988 for three needle age-classes. Needle wettability was assessed by measuring needle–water droplet contact angles. Mean angles per site and age-class ranged from 73 to 42° and decreased significantly with increasing needle age. Needle contact angles were highly correlated with fog acidity (R = 0.99), decreasing with increasing acidity. Angles were lower on needles from declining trees than on needles from visually healthy trees. Epicuticular wax amount was highly correlated with quantity of fog collected at the sites (R = 0.99). Needles from trees at the inland site located outside the coastal fog zone had the smallest wax deposits, while needles from trees exposed to the greatest amount of fog had the largest wax deposits. Epicuticular wax was comprised of secondary alcohols (42%), diols (19%), alkyl esters (16%), primary alcohols (6%), hydroxy fatty acids (2%), and fatty acids (1%). Estolides (14%) in the wax were tentatively identified but not confirmed by mass spectrometry. Needles from trees exposed to the most fog had the greatest amounts of secondary alcohols and alkyl esters. Needles from trees not exposed to fog had greater amounts of diols. There was no obvious relationship between fog acidity and wax chemical composition.

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Xie, Yi Min, Shanqing Xu, Claire Shuiqing Zhang, and Charlie Changli Xue. "Examination of Surface Conditions and Other Physical Properties of Commonly Used Stainless Steel Acupuncture Needles." Acupuncture in Medicine 32, no. 2 (April 2014): 146–54. http://dx.doi.org/10.1136/acupmed-2013-010472.

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Objectives The present work examined the surface conditions and various other physical properties of sterilised single-use stainless steel acupuncture needles from two of the most popular brands widely used in many countries. Methods Scanning electron microscope (SEM) images were taken for 10 randomly chosen needles from each brand. Further SEM images were taken after each of these needles underwent a standard manipulation with an acupuncture needling practice gel. A comparison of forces and torques during the needling process was also carried out. Results The SEM images revealed significant surface irregularities and inconsistencies at the needle tips, especially for needles from one of the two brands. Metallic lumps and small, loosely attached pieces of material were observed on the surfaces of some needles. Some of the lumps and pieces of material seen on the needle surfaces disappeared after the acupuncture manipulation. If these needles had been used on patients, the metallic lumps and small pieces of material could have been deposited in human tissues, which could have caused adverse events such as dermatitis. Malformed needle tips might also cause other adverse effects including bleeding, haematoma/bruising, or strong pain during needling. An off-centre needle tip could result in the needle altering its direction during insertion and consequently failing to reach the intended acupuncture point or damaging adjacent tissues. Conclusions These findings highlight the need for improved quality control of acupuncture needles, with a view to further enhancing the safety and comfort of acupuncture users.

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Facciorusso, Antonio, Valentina Del Prete, Vincenzo Rosario Buccino, Purvi Purohit, Puneet Setia, and Nicola Muscatiello. "Diagnostic yield of Franseen and Fork-Tip biopsy needles for endoscopic ultrasound-guided tissue acquisition: a meta-analysis." Endoscopy International Open 07, no. 10 (October 2019): E1221—E1230. http://dx.doi.org/10.1055/a-0982-2997.

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Abstract Background and study aims Although newer needle designs are thought to improve diagnostic outcomes of endoscopic ultrasound-guided fine-needle biopsy, there is limited evidence on their diagnostic performance. The aim of this meta-analysis was to provide a pooled estimate of the diagnostic performance and safety profile of Franseen and Fork-tip fine-needle biopsy needles. Patients and methods Computerized bibliographic search on the main databases was performed through March 2019. The primary endpoint was sample adequacy. Secondary outcomes were diagnostic accuracy, optimal histological core procurement, mean number of needle passes, pooled specificity and sensitivity. Safety data were also analyzed. Results Twenty-four studies with 6641 patients were included and pancreas was the prevalent location of sampled lesions. Overall sample adequacy with the two newer needles was 94.8 % (93.1 % – 96.4 %), with superiority of Franseen needle over Fork-tip (96.1 % versus 92.4 %, P < 0.001). Sample adequacy in targeting pancreatic masses was 95.6% and both needles produced results superior to fine-needle aspiration (FNA) (odds ratio 4.29, 1.49 – 12.35 and 1.79, 1.01 – 3.19 with Franseen and Fork-tip needle, respectively). The rate of histological core procurement was 92.5%, whereas diagnostic accuracy and sensitivity were 95 % and 92.8 %, again with no difference between the two needles. Number of needle passes was significantly lower in comparison to FNA (mean difference: –0.42 with Franseen and –1.60 with Fork-tip needle). No significant adverse events were registered. Conclusion Our meta-analysis speaks in favor of use of newer biopsy needles as a safe and effective tool in endoscopic ultrasound-guided tissue acquisition.

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Barszczowska, Lidia, and Mariusz Orion Jędrysek. "Carbon isotope distribution along pine needles (Pinus nigra Arnold)." Acta Societatis Botanicorum Poloniae 74, no. 2 (2011): 93–98. http://dx.doi.org/10.5586/asbp.2005.013.

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In this paper we show spatial carbon isotope variations in black pine (Pinus nigra Arnold) needles, collected in spring 2001 and autumn 2003, from trees at the coast of south-western Croatia island (Žirje) and southern Spain (Benalmadena near Malaga), respectively. Needles were segmented perpendicularly to the longer axis (base, middle and top) and each segment was analysed separately. d13C values in needles from Croatia varied between -26.65‰ to -24.43‰ (2 months old needles) and from -28.25‰ to -25.21‰ (1 year old needles), while d13C values in needles from Spain varied from -27.58‰ to -25.27‰. The difference between d13Cb (base) and d13Ct (top) in the same needle (D13Cb-t) varied from 1.85 to 2.05‰ (in young needles from Croatia), from 0,02 to 1,80‰ (young needles from Spain), and 1.16 to 2.32‰, (in old needles from Croatia). The average D13Cb-t values were 0.78‰ and 1.73‰ in Spain and Croatia, respectively. In each needle the base of the needle was always 13C-enriched as compared to the top of the same needle. This evidences that carbon isotopes are not retranslocated after its fixation into the leaf structure (after the growth process is over). Temperature variation was most probably negligible for the discovered intraneedle carbon isotope distribution. Although, the intraneedle carbon isotope inhomogeneity can be partly the result of seasonal variation in d13C of atmospheric CO2, most probably the remarkably high D13Cb-t values, and regular pattern, are predominantly resulting from isotopic and chemical composition of primary and secondary products contained in the growin part of needle and kinetic isotope fractionation during decomposition of storage materials at the base.

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Journal articles on the topic 'Needlets'

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