Modeling Compressible Non-Newtonian Chicken Flow

This paper addresses a few modeling issues relevant for the basic theoretical understanding of the meat flow behavior in simple geometries. We model the meat mixture as a non-Newtonian compressible fluid. Focusing on conceptually easy-to-follow cases like flow in thin molds, or steady incompressible or compressible flow in straight pipes we derive explicit expressions for the velocity and pressure profiles. For the thin moldcase, we formulate a one-dimensional free-boundary problem able to capture the a priori unknown position of the moving meat-air interface. Special attention is payed on the derivation of the free boundary conditions

Fairness Behind a Veil of Ignorance: A Welfare Analysis for Automated Decision Making

We draw attention to an important, yet largely overlooked aspect of evaluating fairness for automated decision making systems---namely risk and welfare considerations. Our proposed family of measures corresponds to the long-established formulations of cardinal social welfare in economics, and is justified by the Rawlsian conception of fairness behind a veil of ignorance. The convex formulation of our welfare-based measures of fairness allows us to integrate them as a constraint into any convex loss minimization pipeline. Our empirical analysis reveals interesting trade-offs between our proposal and (a) prediction accuracy, (b) group discrimination, and (c) Dwork et al.'s notion of individual fairness. Furthermore and perhaps most importantly, our work provides both heuristic justification and empirical evidence suggesting that a lower-bound on our measures often leads to bounded inequality in algorithmic outcomes; hence presenting the first computationally feasible mechanism for bounding individual-level inequality.Comment: Conference: Thirty-second Conference on Neural Information Processing Systems (NIPS 2018

A Moral Framework for Understanding of Fair ML through Economic Models of Equality of Opportunity

We map the recently proposed notions of algorithmic fairness to economic models of Equality of opportunity (EOP)---an extensively studied ideal of fairness in political philosophy. We formally show that through our conceptual mapping, many existing definition of algorithmic fairness, such as predictive value parity and equality of odds, can be interpreted as special cases of EOP. In this respect, our work serves as a unifying moral framework for understanding existing notions of algorithmic fairness. Most importantly, this framework allows us to explicitly spell out the moral assumptions underlying each notion of fairness, and interpret recent fairness impossibility results in a new light. Last but not least and inspired by luck egalitarian models of EOP, we propose a new family of measures for algorithmic fairness. We illustrate our proposal empirically and show that employing a measure of algorithmic (un)fairness when its underlying moral assumptions are not satisfied, can have devastating consequences for the disadvantaged group's welfare

Study of burst mode for enhancing the ps-laser cutting performance of lithium-ion battery electrodes

The demand for lithium-ion batteries (LIBs) has increased significantly, leading to an increased focus on high quality production methods. In response to this growing demand, laser technology has been increasingly used for electrode notching and cutting. In addition, the advent of high-power ultrashort lasers equipped with burst mode capabilities represents a promising option for electrode cutting of LIBs. On the other hand, these types of lasers for this purpose are relatively unexplored in the literature. This study investigates the effect of various parameters, including the number of pulses per burst (ranging from 1 to 8), the pulse repetition rate (200.0, 550.3, and 901.0 kHz), and the burst shape (equal pulse peak and increasing pulse peak), on the laser cutting process of aluminum foil, cathode, copper foil, and anode. The results indicate that increasing the number of pulses per burst and the pulse repetition rate improves productivity and quality for all materials, with a more significant effect observed for metal foil than for cathode and anode materials due to the different laser-material interactions for metal foil and active material. The burst shape with equal pulse peaks was found to be a more suitable temporal distribution for cutting all materials compared to an increasing pulse peak distribution. The ablation efficiency was evaluated as a function of the peak fluence of a single pulse within the burst. The results emphasize that higher productivity at higher average power can be achieved by increasing the pulse repetition rate toward the MHz range with moderate pulse energies

A handheld high-sensitivity micro-NMR CMOS platform with B-field stabilization for multi-type biological/chemical assays

We report a micro-nuclear magnetic resonance (NMR) system compatible with multi-type biological/chemical lab-on-a-chip assays. Unified in a handheld scale (dimension: 14 x 6 x 11 cm³, weight: 1.4 kg), the system is capable to detect<100 pM of Enterococcus faecalis derived DNA from a 2.5 μL sample. The key components are a portable magnet (0.46 T, 1.25 kg) for nucleus magnetization, a system PCB for I/O interface, an FPGA for system control, a current driver for trimming the magnetic (B) field, and a silicon chip fabricated in 0.18 μm CMOS. The latter, integrated with a current-mode vertical Hall sensor and a low-noise readout circuit, facilitates closed-loop B-field stabilization (2 mT → 0.15 mT), which otherwise fluctuates with temperature or sample displacement. Together with a dynamic-B-field transceiver with a planar coil for micro-NMR assay and thermal control, the system demonstrates: 1) selective biological target pinpointing; 2) protein state analysis; and 3) solvent-polymer dynamics, suitable for healthcare, food and colloidal applications, respectively. Compared to a commercial NMR-assay product (Bruker mq-20), this platform greatly reduces the sample consumption (120x), hardware volume (175x), and weight (96x)

The effect of different concentrations of oxygen on postoperative nausea and vomiting after spinal anesthesia

چکیده: زمینه و هدف: تهوع و استفراغ از عوارض شایع پس از عمل جراحی به روش بیهوشی عمومی و نخاعی می باشد. جهت پیشگیری یا درمان تهوع و استفراغ پس از عمل از داروهای مختلف استفاده شده که علیرغم استفاده از آنها این عارضه کماکان پس از عمل جراحی بطور شایع دیده می شود. از طرفی در برخی از تحقیقات استفاده از اکسیژن با غلظت بالا توانسته است سبب کاهش تهوع و استفراغ پس از عمل جراحی، متعاقب بیهوشی عمومی شود. با توجه به آنکه تاکنون هیچ تحقیقی در مورد تأثیر اکسیژن بر روی تهوع و استفراغ پس از عمل جراحی تحت بیهوشی نخاعی انجام نشده است در این تحقیق اثرات اکسیژن با غلظت های مختلف مورد بررسی قرار گرفته است. روش بررسی: در این مطالعه که از نوع کار آزمایی بالینی دوسوکور است تعداد 132 بیمار با مشخصات ASAI,II (American Society of Anesthesiologyists) در محدوده سنی 70-15 سال، داوطلب عمل جراحی جا اندازی و ثابت کردن باز شکستگی ساق پا تحت بِیهوشی نخاعی، بطور تصادفی به سه گروه مساوی تقسیم شدند. پس از انجام بِیهوشی نخاعی با محلول بوپی واکائین 5/. در حین عمل از اکسیژن با غلظت های 30 (گروه اول)، 50 (گروه دوم) و70 (گروه سوم) استفاده شد. تعداد دفعات استفراغ با مشاهده و شدت تهوع به کمک پرسشنامه (Visual Analogue Scale=VAS) ثبت گردید. اطلاعات بدست آمده توسط آزمون های کای دو و ANOVA و با استفاده از نرم افزار SPSS مورد تجزیه و تحلیل آماری قرار گرفته و 05/0p< معنی دار قلمداد گردید. یافته ها: نتایج این بررسی نشان داد که بین میانگین تعداد دفعات استفراغ، شدت تهوع و میزان مصرف متوکلوپرامید حین عمل و در ساعات 2، 12 و 24 پس از عمل، در گروههای 1، 2 و 3 اختلاف آماری معنی دار وجود نداشت. نتیجه گیری: استفاده از اکسیژن با غلظت های بالاتر، در مقایسه با دوزهای کمتر باعث کاهش تهوع، استفراغ و یا مصرف متوکلوپرامید و حین عمل و پس از عمل جراحی نمی شود

Examining the relationship between critical-thinking skills and decision-making ability of emergency medicine students

Background and Aims: Critical-thinking ability would enable students to think creatively and make better decisions and makes them make a greater effort to concentrate on situations related to clinical matters and emergencies. This can bridge the gap between the clinical and theoretical training. Therefore, the aim of the present study is to examine the relationship between critical-thinking ability and decision-making skills of the students of Emergency Medicine. Materials and Methods: This descriptive and analytical research was conducted on all the students of medical emergency students (n = 86) in Shahrekord, Iran. The demographic information questionnaire, the California Critical Thinking Skills Test, and a decision-making researcher-made questionnaire were used to collect data. The data were analyzed by SPSS software version 16 using descriptive and analytical statistical tests and Pearson�s correlation coefficient. Results: The results of the present study indicate that the total mean score for the critical thinking was 8.32 ± 2.03 and for decision making 8.66 ± 1.89. There is a significant statistical relationship between the critical-thinking score and decision-making score (P < 0.05). Conclusions: Although critical-thinking skills and decision-making ability are essential for medical emergency professional competence, the results of this study show that these skills are poor among the students. © 2016 Indian Journal of Critical Care Medicine | Published by Wolters Kluwer - Medknow

The long term effects of occupational electromagnetic fields exposure on peripheral blood indexes in workers of aluminum processing factory of Arak

زمینه و هدف: نظریه بیماری زا بودن میدان های الکترومغناطیسی بر روی ساکنان و کارکنان مجاور این میدان ها بخصوص کارسینوژن بودن آنها مورد مطالعات زیادی قرار گرفته است. ولی نتایج آنها قطعیت نیافته و هنوز مناقشات زیادی در این مورد وجود دارد. این تحقیق به منظور بررسی اثر میدان های الکترومغناطیسی با شدت بالا بر شاخص های خون محیطی افرادی که بطور طولانی مدت (حداقل سه سال) در مجاورت این میدان ها بوده اند طراحی و اجرا گردید. روش بررسی: در یک مطالعه آینده نگر کارگرانی که در کارگاه الکترولیز کارخانه آلومینیوم اراک کار می کنند مورد بررسی قرار گرفتند. ابتدا با کمک گروه بهداشت صنعتی از قسمت های مختلف کارگاه الکترولیز گوس متری به عمل آمد و سپس دویست نفر از کارگران شاغل در کارگاه انتخاب و دویست نفر نیز از افرادی که در سایر قسمت ها شاغل بوده و در معرض میدان مغناطیسی نبودند با رعایت معیارهای ورود انتخاب شدند و هر دو گروه از نظر شرح حال، معاینه بالینی بررسی و پرسشنامه برای آنها تکمیل شد. سپس در دو نوبت به فاصله یکسال برای هر دو گروه CBC و شمارش پلاکت انجام شد. نهایتاً داده ها با استفاده از آمار توصیفی و تحلیلی (t مستقل) و نرم افزار SPSS تجزیه و تحلیل گردید. یافته ها: افراد دو گروه از نظر میانگین سنی و جنسی تفاوتی نداشتند. میانگین شاخص های خونی گروه مواجهه یافته در دو سال متوالی در رده گلبول های سفید، نوتروفیل ها، گلبول های قرمز، هموگلوبین، هماتوکریت و MCV بیشتر از گروه مواجهه نیافته بود (05/0

Intra-operative point-of-procedure delineation of oral cancer margins using optical coherence tomography.

ObjectivesSurgical margin status is a significant determinant of treatment outcome in oral cancer. Negative surgical margins can decrease the loco-regional recurrence by five-fold. The current standard of care of intraoperative clinical examination supplemented by histological frozen section, can result in a risk of positive margins from 5 to 17 percent. In this study, we attempted to assess the utility of intraoperative optical coherence tomography (OCT) imaging with automated diagnostic algorithm to improve on the current method of clinical evaluation of surgical margin in oral cancer.Materials and methodsWe have used a modified handheld OCT device with automated algorithm based diagnostic platform for imaging. Intraoperatively, images of 125 sites were captured from multiple zones around the tumor of oral cancer patients (n = 14) and compared with the clinical and pathologic diagnosis.ResultsOCT showed sensitivity and specificity of 100%, equivalent to histological diagnosis (kappa, ĸ = 0.922), in detection of malignancy within tumor and tumor margin areas. In comparison, for dysplastic lesions, OCT-based detection showed a sensitivity of 92.5% and specificity of 68.8% and a moderate concordance with histopathology diagnosis (ĸ = 0.59). Additionally, the OCT scores could significantly differentiate squamous cell carcinoma (SCC) from dysplastic lesions (mild/moderate/severe; p ≤ 0.005) as well as the latter from the non-dysplastic lesions (p ≤ 0.05).ConclusionThe current challenges associated with clinical examination-based margin assessment could be improved with intra-operative OCT imaging. OCT is capable of identifying microscopic tumor at the surgical margins and demonstrated the feasibility of mapping of field cancerization around the tumor