bluuebunny/crossref_metadata_2025 huggingface dataset:
Programming as Language and Manipulative for Second-Grade Mathematics
Authors: Goldenberg E. Paul , Carter Cynthia J. , Mark June , Reed Kristen , Spencer Deborah , Coleman Kate
Published: February 2021

This article reports on an exploration of how second-graders can learn mathematics through programming. We started from the theory that a suitably designed programming language can serve children as a language for expressing and experimenting with mathematical ideas and processes in order to do mathematics and thereby, with appropriate tasks and teaching, learn and enjoy the subject. This is very different from using the computer as a teaching app or a digital medium for exploration. Children tackled genuine puzzles – problems for which they did not already have a pre-learned solution. So far, we have built four microworlds for second-graders and tested them with a diverse population of well over three hundred children. The microworlds focus on the most critical second-grade mathematical content (as mandated in state standards), let children pick up all key programming ideas in contexts that make them ‘obvious’ (to maintain focus on the mathematics) and suppress all other distractions to minimize overhead for teachers or students using the microworlds. Because children see the results of the actions they articulate (in the computer language, Snap!), they can evaluate their methods and solutions themselves. The feedback is purely the outcome, not happy or sad sounds from the computer. Notably, nearly all children showed intense engagement, some choosing microworlds even outside of mathematics time. Teachers spontaneously reported this as well, with special mention of children whom they found hard to engage in regular lessons. We report our experiments and observations in the spirit of sharing the ideas and promoting more research.
Computational evaluation of a novel beta radiation probe design using integrated circuits
Authors: King Jeremy W. , Shah Manit D. , Marianno Craig M. , Khatri Sunil P. , Chirayath Sunil S.
Published: February 2021

Researchers at Texas A&M University (TAMU) have designed the radiation integrated circuit (RIC) for deployment as a new radiation detection system. Most integrated circuits are susceptible to radiation-induced failures, and decades of research have gone into solving this problem. Research at TAMU has led to a novel integrated circuit design that utilizes both radiation-hardened areas (RHAs) and radiation-sensitive areas (RSAs) to take advantage of these failures. The RSAs are susceptible to charged particle interactions, allowing the RIC to detect alpha and beta particles. However, beta particles are more penetrating compared to alpha particles, resulting in a lower interaction probability for beta particles incident on a bare RIC. In any material, the higher the beta energy, the deeper the beta particle can penetrate; therefore, the use of a wedge-shaped attenuator for beta particle detection not only increases interaction probability, but also provides the capability to perform maximum beta energy discrimination in the field. The objective of this research was to optimize the design of the RIC. Monte Carlo N-particle radiation transport code (MCNP) simulations assessed the beta particle detection and maximum energy discrimination performance of plate glass, borosilicate (Pyrex®) glass, acrylic (Lucite®), and natural rubber attenuators. In this proof-of-concept analysis, natural rubber was observed to be the optimal attenuating material for the beta probe with respect to maximum energy discrimination capability and weight, but all materials considered proved to be good candidates. The results of this study are promising and indicate the potential to achieve maximum beta particle energy discrimination of 50 keV using a wedged, natural rubber attenuator on the RIC.
Addressing the challenges in projects of water treatment plants and storage of potable water: a case studies of the water supply system in the state of Goiás, Brazil
Authors: de Melo Dores Anne Louise , Corrêa Veloso dos Santos Felipe
Published: February 2021

To elaborate efficient and economical water supply systems is one of the main objectives in the sanitation companies water system projects. In order to address the challenges faced in reaching this objective, this study aims to identify, first, the relation between the percentage of non-conformed samples in treated water and the inefficiency of the filtering units installed in the water treatment plant, and second, if, by drawing the consumption variation curve it is the most efficient way to predict the storage tanks volume—comparing necessary capacity, determined by the consumption curve, and installed capacity, predict by the outdated Brazilian normative. In order to reach answers for these two questions, this study measured the operating efficiency of the treatment plant as well as have set a quantitative comparison between the two dimensioning criteria for storage tanks volume present in the literature. As a result, the analysis provided the authors to detect a focus of contamination in the single-layered filtering units, limited by the filtering capacity of 2–6 m3/(m2 day), whilst operating at 333.13 m3/(m2 day). As well as to detect by the drawing of the consumption variation curve an oversize of 68% and 60% in the dimensioning of the studied storage tanks. With the results provided by this analysis approach, it was possible to efficiently detect and correct critical impairments in the treatment phase and to conclude that a long-term analysis should be drawn in order to affirm if the consumption variation curve is the best design methodology for the reservoirs.
Searching for optimum adsorption curve for metal sorption on soils: comparison of various isotherm models fitted by different error functions
Authors: Sipos Péter
Published: February 2021

Studies comparing numerous sorption curve models and different error functions are lacking completely for soil-metal adsorption systems. We aimed to fill this gap by studying several isotherm models and error functions on soil-metal systems with different sorption curve types. The combination of fifteen sorption curve models and seven error functions were studied for Cd, Cu, Pb, and Zn in competitive systems in four soils with different geochemical properties. Statistical calculations were carried out to compare the results of the minimizing procedures and the fit of the sorption curve models. Although different sorption models and error functions may provide some variation in fitting the models to the experimental data, these differences are mostly not significant statistically. Several sorption models showed very good performances (Brouers-Sotolongo, Sips, Hill, Langmuir-Freundlich) for varying sorption curve types in the studied soil-metal systems, and further models can be suggested for certain sorption curve types. The ERRSQ error function exhibited the lowest error distribution between the experimental data and predicted sorption curves for almost each studied cases. Consequently, their combined use could be suggested for the study of metal sorption in the studied soils. Besides testing more than one sorption isotherm model and error function combination, evaluating the shape of the sorption curve and excluding non-adsorption processes could be advised for reliable data evaluation in soil-metal sorption system.
An Internet of Medical Things System to Increase Continuous Positive Airway Pressure Usage in Patients with Sleep-Disordered Breathing
Authors: Croatti Angelo , Montagna Sara , Lombardi Carolina , Parati Gianfranco , Pengo Martino F. , Silvani Alessandro
Published: February 2021

Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder associated with increased daytime sleepiness and cardiovascular risk. Continuous positive airway pressure (CPAP), requiring a pressure-generating device connected via tubing to a mask during sleep, is an effective treatment. However, patients’ adherence to CPAP is often suboptimal. Behavioral interventions are effective in improving adherence to CPAP. We aimed to provide proof of principle for the operation of a low-cost, self-standing, internet-based system to measure and promote adherence to CPAP. The system is composed of triaxial acceleration sensors attached to the CPAP mask and to the wrist, able to record CPAP usage information, and a mobile app that collects such information and, thorough a chatbot, feeds back to the patient to improve adherence to treatment. The mask subsystem identifies time periods when the mask is put on based on relatively high values of the ratio between acceleration spectral power at frequencies$$< 0.35$$<0.35Hz vs. 0.35–2 Hz over 1-min windows. Accuracy in identification may be increased taking account of the surges in the standard deviation of wrist accelerations over 1-min windows that accompany putting on and taking off the mask. The whole system can represent a unique tool capable of monitoring and improving patients’ adherence to CPAP treatment. Its main strength lies in its simplicity, low cost, and independence from the specific CPAP device and mask employed.
Vaginal Microbiome Is Associated With Vulvodynia, Vulvar Pain Syndrome: A Case-Control Study
Authors: Park So Yun , Lee Eun Sil , Lee Sa Ra , Kim Sung Hoon , Chae Hee Dong
Published: February 2021

Introduction

Vulvodynia, vulvar pain syndrome, is defined as vulvar pain of at least a 3-month duration without a clear identifiable cause, which may have associated factor and the etiology and treatment of this challenging disease is still unclear. Dyspareunia is a relevant symptom of patients with vulvodynia. Vaginal microbiome has known an important role in local immune-inflammatory responses and it may be important pathogenic mechanism in vulvodynia.

Aim

The objective of this study was to investigate the association of vaginal microbiome and vulvodynia.

Methods

We analyzed the microbial compositions of the vestibule and vagina among women with clinically diagnosed vulvodynia (n = 22) and age-matched healthy controls (n = 22) without vulvodynia. The compositions of bacterial microbiomes were compared by pyrosequencing of the 16S rRNA.

Main outcome measure

Vaginal microbiome alpha and beta diversity were assessed using the Shannon diversity index and Heat map. Linear discriminant analysis effect size was used to find out marker for vulvodynia.

Results

There were no significant differences in the age, duration of marriage, history of gynecologic surgery, parity, and menopause status between cases and controls. A total of 1,661,934 high-quality pyrosequencing reads was obtained to evaluate bacterial diversity, and 50,246 unique sequences represented all phylotypes. The type and mean number of the genera were not different between cases and controls. However, the most predominant phyla of bacteria were significantly different between cases and controls. 3 phyla (Firmicutes, Actinobacteria, and Tenericutes) and 11 genera including Gardnerella, Ureaplasma, Achromobacter, Mycoplasma, and Bifidobacteria were significantly more prevalent in cases than in controls (P < .05). Linear discriminant analysis effect size analysis suggest the Bifidobacterium, Mycoplasma, and Fenollaria species can be potential markers for vulvodynia.

Conclusion

Our results suggest the differences in vaginal microbiome can be associated with the vulvodynia.
Access to Liver Transplantation for Hepatocellular Carcinoma: Does Candidate Age Matter?
Authors: Ahmed Ola , Vachharajani Neeta , Chang Su-Hsin , Park Yikyung , Khan Adeel S. , Chapman William C. , Doyle Majella B.
Published: February 2021

BACKGROUND:

Liver transplantation (LT) offers an effective alternative treatment for unresectable hepatocellular carcinoma (HCC). Despite its growing acceptance and longer life expectancy rates, survival data in older patients are conflicting and consensus guidelines are lacking in terms of a cut-off age range for operations.

STUDY DESIGN:

We explored our prospectively maintained institutional database to identify patients diagnosed with HCC between January 1, 2002 and December 31, 2019. Long-term oncologic outcomes were analyzed in patients undergoing LT or hepatic resection, with patient age considered as the primary variable.

RESULTS:

In total, 1,629 patients with HCC were identified, of whom 700 were considered for curative operations (LT, n = 538; resection, n = 162). Patients older than 65 years were less likely to be considered for LT (p < 0.01), although there were no age-related differences in the de-listing rate among age groups (p = 0.90). Older patients had overall survival (OS) outcomes comparable with younger patients after LT (3-year OS: 85.5% vs 84%; 5-year OS: 73.9% vs 77%; p = 0.26). Long-term survival was lower in the group who underwent resection, however, older patients still demonstrated equivalent OS outcomes (3-year OS: 59% vs 64.8%; 5-year OS: 44.8% vs 49%; p = 0.13). There were no differences in the development of local or distant metastatic disease between groups.

CONCLUSIONS:

Although older candidates were less likely to be considered for LT in the management of HCC, judicious matching can lead to OS data comparable with their younger counterparts. Previous age misconceptions need to be challenged without the concern of worse long-term oncologic outcomes after surgery.
Penile Length Measurement: Methodological Challenges and Recommendations, a Systematic Review
Authors: Cakir Omer Onur , Pozzi Edoardo , Castiglione Fabio , Alnajjar Hussain M. , Salonia Andrea , Muneer Asif
Published: February 2021

Background

Penile length measurement techniques vary widely in published studies leading to inaccurate and nonstandardized measurements.

Aim

To review the methodology used to report data in studies evaluating penile length and provide a detailed recommendation in conducting future high-quality research.

Methods

The MEDLINE database was searched for randomized clinical trials and open-label prospective or retrospective studies.

Outcomes

The panel reviewed the modality of data reporting on these specific areas: patients’ age and assessment, patient position, type of measurement instrument used, penile length technique description, examination conditions, and actual examiner.

RESULTS

Overall, 70 studies investigating penile length were selected; among these, 72.85% included at least 50 patients: 16 prospective studies, 5 randomized clinical trials, and 49 retrospective cross-sectional studies. Amongst all studies, 90% reported to measure penile length by health care practitioners in clinical settings. Penile length was assessed in all 70 studies, whereas penile girth was measured in 57.14% of patients. A semi-rigid ruler was the most commonly used measurement aid to assess penile length/girth in 62.86% of studies. Penile measurements were reportedly obtained: (i) stretched state, 60%; (ii) flaccid state only, 52.68%; and (iii) during erection, 27.43%. All studies investigating the penile length in an erect state were simultaneously assessing penile length in the flaccid state. About 90% of studies investigated penile length in adults, whereas 10% were conducted in adolescents.

Clinical Implications

The use of shared methodology to assess penile length in both adults and adolescents allows more accurate and standardized measurements.

Strength & Limitations

A systematic review of the published literature allowed proper data interpretation in order to provide accurate recommendations. Main limitations of the study relied on a relatively limited number of databases for the identification of potentially eligible studies.

CONCLUSION

The methodology used in studies measuring penile length should be precise and standardized in order to provide accurate data to both clinicians and researchers.
Dielectric response of (Pb0.7Nd0.15Bi0.15)(Fe0.3Ti0.7)O3 material
Authors: Samal S.K. , Pradhan S.K. , Mallick M.K. , Choudhary R.N.P. , Bhuyan S.
Published: February 2021

A neodymium (Nd substituted BiFeO3: BFO and PbTiO3: PT) binary electronic compound has been developed with the help of solid state oxide-mixing process. The electrical properties, such as dielectric response (relative permittivity & loss tangent), resistive behavior (impedance spectrum) and conductivity, as well as electric modulus of the developed ceramic powder material, have been delineated. The compound entails high dielectric constant with relatively lower loss tangent with increased conductivity which affirmed the material as a potential contender for ferroelectric based electronic device applications.
Impact of Assimilation of Satellite Retrieved Ocean Surface Winds on the Tropical Cyclone Simulations Over the North Indian Ocean
Authors: Bhate Jyoti , Munsi Arpita , Kesarkar Amit , Kutty Govindan , Deb Sanjib K.
Published: February 2021

The study intends to examine the impact of assimilation of ocean surface winds on the simulation of the tropical cyclones Ockhi, Mekunu, and Luban formed over the north Indian Oceans. We have conducted two assimilation experiments, cyclic control (CyclicCntl) and Hybrid, using the Weather Research and Forecast model. The CyclicCntl experiment and Hybrid experiment are the analysis generated without and with adding ocean surface winds, respectively. The ocean surface winds from Ocean Scatterometer, Advanced Scatterometer, and Windsat are assimilated using the ensemble three‐dimensional variational assimilation technique. The analysis generated by Hybrid and CyclicCntl is compared with the ocean surface winds observations from buoys, and it is found that the assimilation of ocean surface winds reduces the root mean square error between observation and analysis for zonal and meridional winds by 2–3 m s−1 (42%) compared to CyclicCntl simulations. The comparison with the International Best Track Archive for Climate Stewardship locations of cyclones derived from the analyses indicates that track error is maximum in genesis and landfall stage for both the Hybrid and CyclicCntl experiments, and the average track error is less than 80 km for the three cyclones. In a Hybrid experiment, during the intensifications from deep depression to the very severe cyclonic storm, the wind speed enhancement is dominant over the southeast and northwest sectors of the eyewall regions and subsequently in the rainband region. Thus, the assimilation of ocean surface winds from the three sensors improves the prediction of intensity and the evolution of tropical cyclones in general.
Inhibition of Bruton’s tyrosine kinase as a therapeutic strategy for chemoresistant oral squamous cell carcinoma and potential suppression of cancer stemness
Authors: Liu Shao-Cheng , Wu Yang-Che , Huang Chih-Ming , Hsieh Ming-Shou , Huang Ting-Yi , Huang Chin-Sheng , Hsu Tung-Nien , Huang Mao-Suan , Lee Wei-Hwa , Yeh Chi-Tai , Lin Chun-Shu
Published: February 2021

Locally advanced oral squamous cell carcinoma (OSCC) requires multimodal therapy, including surgery and concurrent chemoradiotherapy (CCRT). CCRT-resistant and recurrent cancer has a poor prognosis. We investigated the effects of Bruton’s tyrosine kinase (BTK) on CCRT-resistant OSCC tissues. The effect of ibrutinib, a first-in-class BTK inhibitor, was tested on stem cell-like OSCC tumorspheres. A tissue array was constructed using tissue samples from 70 patients with OSCC. Human OSCC cell lines, SAS, TW2.6 and HSC-3, were examined. Wound healing, Matrigel invasion, and tumorsphere formation assays, as well as immunofluorescence analysis and flow cytometry, were used to investigate the effects of BTK knockdown (shBTK), ibrutinib, cisplatin, and ibrutinib/cisplatin combination on OSCC cells. We demonstrated that BTK was aberrantly highly expressed in the clinical CCRT-resistant OSCC tissue array, which resulted in poor overall survival in our local Tri-Service General Hospital and freely accessible TCGA OSCC cohorts. shBTK significantly downregulated the stemness markers Nanog, CD133, T cell immunoglobulin-3 (TIM-3), and Krüppel-like factor 4 (KLF4) in SAS tumorspheres and attenuated OSCC cell migration and colony formation. Ibrutinib reduced the number of aldehyde dehydrogenase (ALDH)-rich OSCC cells and reduced tumorsphere formation, migration, and invasion in a dose-dependent manner. Compared with ibrutinib or cisplatin monotherapy, the ibrutinib/cisplatin combination significantly reduced the formation of ALDH + OSCC tumorspheres and enhanced apoptosis. These results demonstrate that ibrutinib effectively inhibits the CSCs-like phenotype of OSCC cells through dysregulation of BTK/CD133 signaling. The ibrutinib/cisplatin combination may be considered for future clinical use.
Direct observation of ion emission from charged aqueous nanodrops: effects on gaseous macromolecular charging
Authors: Harper Conner C. , Brauer Daniel D. , Francis Matthew B. , Williams Evan R.
Published: February 2021

Ion evaporation from aqueous nanodrops is measured for the first time using charge detection mass spectrometry, and the origin of solute ion dependent charging of large (MDa) macromolecules is revealed.
A novel biocompatible polymeric blend for applications requiring high toughness and tailored degradation rate
Authors: Heidari Behzad Shiroud , Chen Peilin , Ruan Rui , Davachi Seyed Mohammad , Al-Salami Hani , De Juan Pardo Elena , Zheng Minghao , Doyle Barry
Published: February 2021

Finding the right balance in mechanical properties and degradation rate of biodegradable materials for biomedical applications is challenging, not only at the time of implantation but also during biodegradation.
Single-atom silver loaded on tungsten oxide with oxygen vacancies for high performance triethylamine gas sensors
Authors: Zeng Jiyang , Rong Qian , Xiao Bin , Yu Ruohan , Zi Baoye , Kuang Xinya , Deng Xiyu , Ma Yiwen , Zhang Jin , Wu Jinsong , Liu Qingju
Published: February 2021

Traditional sensor materials for detecting gaseous and volatile compounds still have relatively low sensitivity and high price, which limits their large-scale applications.
Secrecy transmission capacity in mobile ad hoc networks with security‐aware Aloha protocol
Authors: Li Xiaochen , Zhang Yuanyu , Shen Yulong , Jiang Xiaohong
Published: February 2021

Mobile ad hoc networks (MANETs) represent a class of important network models for supporting various critical applications, while the security breach due to eavesdropping attacks has been a critical issue. This study investigates the security issue of MANETs from the perspective of physical layer security (PLS). In particular, by combining PLS techniques [e.g. artificial noise (AN) injection and Secrecy Guard zoNe (SGN)] and the conventional Aloha protocol, the authors first propose an AN‐based Aloha protocol and a SGN‐based Aloha protocol to ensure secure medium access for legitimate transmitters. In the AN‐based Aloha protocol, all potential transmitters are allowed to be active and each active transmitter injects AN into its transmitted signals to confuse eavesdroppers. In the SGN‐based protocol, each potential transmitter has an SGN, a circle centred at itself, and only the potential transmitters whose SGN contains no eavesdroppers are allowed to be active. To understand the security performances of the proposed security‐aware Aloha protocols, the authors then apply tools from Stochastic Geometry to analyse the secrecy transmission capacity (STC) performances of MANETs under both protocols. Finally, the authors provide simulation/numerical results to corroborate the proposed theoretical analysis and also to show the impacts of network parameters on the STC performances.
Protection schemes and settings of DC distribution systems
Authors: Ke Jia , Cong Chen , Qijuan Zhao , Tao Feng , Tianshu Bi , Haijun Liu
Published: February 2021

Flexible DC distribution system has become the research and development trend of the future distribution network with its unique advantages such as high efficiency and flexibility. However, the DC fault identification and protection is challenging due to the fact that the short‐circuit current provided by converters is limited and last for a very short period, how to identify and isolate faults reliably using limited fault transient information becomes a serious problem faced by system protection. Based on the analysis of the fault characteristics of three typical faults in the DC distribution system, the setting principle and the calculation methods are proposed, and the reasonable range of protection setting boundaries is derived. According to the requirements of protections, the parameters of the actual DC distribution system are used for setting calculations, and a complete set of DC line protection schemes is designed in this study. Finally, the performance of the proposed protection scheme is verified in PSCAD/EMTDC simulation platform, the built simulation model has been successfully applied to the analysis and calculation in the commissioning of the DC distribution system.
Krebserkrankung und das letzte Lebensjahr: Palliative Leistungen, Krankenhausaufenthalte und Sterbeort
Authors: Blaschke Katja , Hermes-Moll Kerstin , Lappe Veronika , Ihle Peter , Baumann Walter , Schubert Ingrid
Published: February 2021

Einleitung Palliativ versorgte Patientinnen und Patienten haben zu einem hohen Anteil onkologische Diagnosen. Die spezialisierte ambulante Palliativversorgung (SAPV) richtet sich an Erkrankte mit komplexem Symptomgeschehen und intensivem Betreuungsbedarf und soll eine Betreuung im häuslichen Umfeld bis zum Lebensende ermöglichen. In Hessen wurden ab 2009 die ersten SAPV-Angebote geschaffen. Entsprechend untersucht diese Studie (i) die Inanspruchnahme von SAPV und spezialisierten stationären palliativen Leistungen im letzten Lebensjahr von Krebserkrankten, (ii) die SAPV verordnende Arztgruppe und (iii) den Sterbeort und Krankenhausaufenthalte in den letzten 91 Lebenstagen.

Methoden In der retrospektiven Sekundärdatenanalyse wurden Daten der AOK Hessen für 2009–2014 deskriptiv ausgewertet. Studienpopulation waren an Brust-, Prostata- oder Darmkrebs Erkrankte, die im jeweiligen Beobachtungsjahr (2010–2014) verstarben und 360 Tage vor ihrem Tod durchgängig versichert waren.

Ergebnisse In die Studie konnten je nach Beobachtungsjahr 492–545 Personen mit Brust-, 546–625 mit Prostata- und 709–752 mit Darmkrebs eingeschlossen werden. In allen 3 Gruppen Krebserkrankter stieg zwischen 2010 und 2014 der Anteil mit Inanspruchnahme von mindestens einer Palliativleistung. Die Häufigkeit der Inanspruchnahme von SAPV-Leistungen lag bei den betrachteten Krebserkrankten meist höher im Vergleich zu Palliativstationen bzw. stationären Hospizen. SAPV wurde bei den 3 Krebsdiagnosen zu über 90 % von Hausärztinnen bzw. -ärzten verordnet. Sowohl der Anteil von Personen mit einem Krankenhausaufenthalt in den letzten 91 Lebenstagen als auch der im Krankenhaus Verstorbenen ging von 2010 bis 2014 bei allen 3 Krebsarten zurück.

Schlussfolgerung Die Ergebnisse sind vor dem Hintergrund des Aufbaus der SAPV in Hessen zu bewerten. Die Zunahme an SAPV-Leistungen und der Rückgang an Krankenhauseinweisungen am Lebensende weist auf eine gelungene Etablierung der SAPV in Hessen hin.
Heterogeneity in Bleeding Tendency and Arthropathy Development in Individuals with Hemophilia
Authors: Rehill Aisling M. , McCluskey Seán , O'Donnell James S. , Dockal Michael , Preston Roger J.S. ,   on behalf of the iPATH Study Group
Published: February 2021

People with hemophilia (PWH) have an increased tendency to bleed, often into their joints, causing debilitating joint disease if left untreated. To reduce the incidence of bleeding events, PWH receive prophylactic replacement therapy with recombinant factor VIII (FVIII) or FIX. Bleeding events in PWH are typically proportional to their plasma FVIII or IX levels; however, in many PWH, bleeding tendency and the likelihood of developing arthropathy often varies independently of endogenous factor levels. Consequently, many PWH suffer repeated bleeding events before correct dosing of replacement factor can be established. Diagnostic approaches to define an individual's bleeding tendency remain limited. Multiple modulators of bleeding phenotype in PWH have been proposed, including the type of disease-causing variant, age of onset of bleeding episodes, plasma modifiers of blood coagulation or clot fibrinolysis pathway activity, interindividual differences in platelet reactivity, and endothelial anticoagulant activity. In this review, we summarize current knowledge of established factors modulating bleeding tendency and discuss emerging concepts of additional biological elements that may contribute to variable bleeding tendency in PWH. Finally, we consider how variance in responses to new gene therapies may also necessitate consideration of patient-specific tailoring of treatment. Cumulatively, these studies highlight the need to reconsider the current “one size fits all” approach to treatment regimens for PWH and consider therapies guided by the bleeding phenotype of each individual PWH at the onset of therapy. Further characterization of the biological bases of bleeding heterogeneity in PWH, combined with the development of novel diagnostic assays to identify those factors that modulate bleeding risk in PWH, will be required to meet these aspirations.
Point-of-Care Diagnostic Assays and Novel Preclinical Technologies for Hemostasis and Thrombosis
Authors: Caruso Christina , Lam Wilbur A.
Published: February 2021

Hemostasis is a complex wound-healing process involving numerous mechanical and biochemical mechanisms and influenced by many factors including platelets, coagulation factors, and endothelial components. Slight alterations in these mechanisms can lead to either prothrombotic or bleeding consequences, and such hemostatic imbalances can lead to significant clinical consequences with resultant morbidity and mortality. An ideal hemostasis assay would not only address all the unique processes involved in clot formation and resolution but also take place under flow conditions to account for endothelial involvement. Global assays do exist; however, these assays are not flow based. Flow-based assays have been limited secondary to their large blood volume requirements and low throughput, limiting potential clinical applications. Microfluidic-based assays address the aforementioned limitations of both global and flow-based assays by utilizing standardized devices that require low blood volumes, offer reproducible analysis, and have functionality under a range of shear stresses and flow conditions. While still largely confined to the preclinical space, here we aim to discuss these novel technologies and potential clinical implications, particularly in comparison to the current, commercially available point-of-care assays.
The Impact of Away Rotations on the Ophthalmology Residency Match
Authors: Tso Hanna L. , Young Jason , Boente Charline S. , Yung Chi Wah
Published: February 2021

Background The ophthalmology residency match is highly competitive, and fourth-year medical students frequently complete away rotations at other institutions hoping to increase their chances of matching.

Objective The study aimed to determine the impact of away rotations on the ophthalmology residency selection process and to provide recommendations to faculty for counseling fourth-year medical students as they prepare for the ophthalmology match.

Methods A survey was sent in June 2020 to program directors (PDs), medical student educators (MSEs), and residents at 119 accredited ophthalmology residency programs via the Association of University Professors of Ophthalmology e-mail listserv. The 43 PDs and 38 MSEs who responded were asked questions about their views regarding away rotations and visiting students during the residency selection process. The 83 resident respondents were asked about their interview and match success after completing away rotations. Categorical variables were analyzed by Chi-square test.

Results The majority of PDs and MSEs typically recommend that fourth-year medical students complete away rotations (p = 0.022 and p = 0.194, respectively). The majority believe that an away rotation will increase the chance of the applicant matching with the host institution (p = 0.004 and p = 0.001, respectively). The vast majority of PDs were more likely to offer an interview to a visiting student compared with another equally qualified applicant (p < 0.001). However, only one-third of PDs were typically more likely to rank an away rotator higher on their rank list (p = 0.047). Two-thirds of residents completed at least one away rotation in medical school (mean = 1.7 rotations). The majority received interview invitations from at least some of their host institutions (p < 0.001). Approximately one-fifth ultimately matched at a host residency program (p < 0.001).

Conclusion The majority of ophthalmology PDs and MSEs surveyed recommend that fourth-year medical students complete away rotations and believe that these rotations will increase the chance of the applicant matching at a host institution. The PDs are more likely to offer an interview to a visiting student compared with another equally qualified applicant. For some programs, visiting students may also receive special consideration by being ranked higher on a program's rank list and being more likely to match.
Optimal Fluoroscopic Angulation to Determine Intercondylar Notch Violation during Pediatric Medial Patellofemoral Ligament Reconstruction
Authors: Knapik Derrick M. , McCarthy Conor F. , Drummond Ian , Liu Raymond W. , Gilmore Allison
Published: February 2021

Previous anatomic data has suggested that during pediatric medial patellofemoral ligament (MPFL) reconstruction, the femoral tunnel must be angled distally and anteriorly to avoid damage to the distal femoral physis and then intercondylar notch. The purpose of this study was to determine the optimal degree of fluoroscopic angulation necessary to radiographically determine the presence of intercondylar notch violation. Fourteen adult cadaveric human femora were disarticulated and under fluoroscopic guidance, Schöttle's point was identified. A 0.62-mm Kirschner wire was then drilled through the condyle to create minimal notch violation. The femur was then placed on a level radiolucent table and coronal plane radiographs angled from −15 to 60 degrees were obtained in 5-degree increments to determine the fluoroscopic angle at which intercondylar notch violation was most evident. Grading of optimal fluoroscopic angle between two authors found that violation of the notch was the best appreciated at a mean angle of 43 ± 15 degrees from neutral. Results from this study emphasize the importance of angling the beam to essentially obtain a notch view to assess for a breech.
Dynamic pricing under competition using reinforcement learning
Authors: Kastius Alexander , Schlosser Rainer
Published: February 2021

Dynamic pricing is considered a possibility to gain an advantage over competitors in modern online markets. The past advancements in Reinforcement Learning (RL) provided more capable algorithms that can be used to solve pricing problems. In this paper, we study the performance of Deep Q-Networks (DQN) and Soft Actor Critic (SAC) in different market models. We consider tractable duopoly settings, where optimal solutions derived by dynamic programming techniques can be used for verification, as well as oligopoly settings, which are usually intractable due to the curse of dimensionality. We find that both algorithms provide reasonable results, while SAC performs better than DQN. Moreover, we show that under certain conditions, RL algorithms can be forced into collusion by their competitors without direct communication.
Achieving drought resilience in the grazing lands of northern Australia: preparing, responding and recovering
Authors: Bowen M. K. , Chudleigh F.
Published: February 2021

Northern Australia is characterised by high rainfall variability and extended droughts that challenge sustainable and profitable management of grazing properties. To achieve drought resilience, emphasis must be placed on supporting livestock managers to prepare for drought as well as implementing appropriate drought response and recovery actions. Here we describe insights and learnings gained from working with scientists, industry development and extension officers, and property managers, to enable more profitable and drought resilient extensive livestock production systems across northern Australia. We provide examples from the modelling and analysis of hypothetical grazing properties representative of enterprises across northern Australia. To prepare for drought, we principally propose the application of the farm-management economics framework to identify investment strategies which can improve enterprise resilience through building wealth over the longer term. The critical first step in drought preparedness for beef businesses was the implementation of management strategies to achieve the optimal herd structure, steer sale age, and breeder body condition. Other key strategies to improve profitability across northern Australia were (1) addressing a phosphorus deficiency for cattle through effective supplementation and (2) establishing adapted perennial legume-grass pastures to improve steer nutrition. In addition, we identify the benefits of working closely with livestock managers and industry to gain adoption of proven technologies that effectively improve decision-making capacity and the drought preparedness of extensive livestock production systems. The usefulness of the farm-management economics approach to assess the relative value of alternative tactical destocking and restocking decisions during drought response and recovery is also discussed. These latter analyses can highlight important differences between options in terms of future profit and cash flow, as well as the ability to rapidly return the property to the most profitable herd structure and age of turnoff, with consideration of production and financial risk. Additionally, integrating pasture growth models with herd or flock economic models can provide insights into the effects, on profitability and sustainability, of alternative destocking and later restocking strategies over the longer term. Combined, the farm-management economics framework approach can support more informed decision-making by livestock producers and hence enable more profitable and drought resilient extensive livestock production systems. However, achieving drought resilience in the grazing lands of northern Australia will require emphasis on drought preparation, in addition to appropriate action in response and recovery phases of drought. Key to this approach is increasing the adoption of strategies that enhance drought preparedness.
Underwater real-time target detection based on key frame and model compression
Authors: Guo Wei , Zhang Youbo , Zhou Yue , Xu Gaofei , Li Guangwei
Published: February 2021

In order to improve the speed and keep high accuracy of UUVs object detection on embedded device. This paper proposes an acceleration strategy based on key frame extraction and model compression. Firstly, selecting shipwreck as target and creating a real-world underwater image dataset of the shipwreck. And this work applies both online and offline data augmentation to accelerate the model convergence and to improve the model generalization. Then, this paper builds a fusion algorithm with structural similarity, color histogram and image entropy to select the key frame of the captured video for removing the redundant information, and analyzing the reason for the complexity of the neural network and the method of model compression. Finally, this work cuts off unimportant structure of network based on channel and layer pruning to reduce model complexity and keeps the model with high accuracy by fine-tuning. The experiment shows the Billion Floating Operations of the compressed YOLOV4 model is reduced to 15.778. On the Nvidia Jetson TX2 embedded image processor, the average detection speed for video with 608 × 608 resolution can reach 15.12FPS. And the detection speed of the video composed of key frames is 2.98 times faster than the raw video.
Design of four-rotor autonomous target-dropping aircraft based on image processing
Authors: Li Ruihan
Published: February 2021

The aim of this study is to design and produce a quad-rotor autonomous target shooting aircraft based on STM32F407 microprocessor and OV7725 image acquisition system. Herein, the quaternion is defined by using Euler’s theorem, navigation coordinate system and carrier coordinate system. Taking STM32F407 master controller as the core, the control system of the aircraft is composed of, distance measuring and height setting module, six-axis motion sensor measurement module, three-axis magnetometer measurement module and camera unit trajectory tracking module. Then, four circuits of the flight control system were designed, including the main control circuit, attitude measurement circuit, throwing rake control circuit and image processing circuit. In addition, three algorithms related to aircraft were prepared, including attitude control cascade PID algorithm, height control algorithm and attitude solution algorithm, and an image processing software was designed. On this basis, the aircraft was built, and finally its flight attitude, height, fixed point, and hover were tested. The results showed that all the algorithms are correct, and the aircraft can successfully pitch, roll, yaw, recognize image trajectory, and automatically drop materials and cruise.
Combining sources from CVE and CNNVD: Data analysis in information security vulnerabilities
Authors: Jin Ruiying , Nan Jing
Published: February 2021

The information technology level of China continues to improve, and various industries are digitalized in different degrees. However, the development of the network has correspondingly brought the trouble of loopholes, which have caused mass economic losses to many enterprises. In the era of big data, it is necessary to understand the characteristics of the ever-emerging vulnerabilities. In this study, we used descriptive statistics and programming techniques to analyze more than 140,000 vulnerability records from CVE and CNNVD. We visualize the development trend of vulnerabilities through descriptive statistics and summarized the characteristics of vulnerabilities in products from manufacturers of different scales. The result shows that large companies usually face more and severer loopholes. Then, multivariate regression is conducted to explore the relationship between vulnerability type, threat type and hazard level. K-means clustering method is employed to select and extract features based on the description paragraphs of vulnerabilities. Finally, we categorize the loopholes according to different patterns, so as to find a breakthrough point for a quicker solution to new vulnerabilities with the existing classified database. The combined sources are proved to be useful for clustering analysis.
Distribution of the benefits of agricultural supply chain cooperation based on interval-valued least-squares pre-nucleolus solutions
Authors: Zhou Fang , Zhu Chaozhi
Published: February 2021

Fair and reasonable profit distribution is the key to the long-term sustainability of agricultural supply chain cooperation alliances, helping to improve cooperation efficiency and increase profitability, which is a typical fuzzy cooperative game problem. We study the cooperative income distribution of the agricultural product supply chain. Based on the idea of least square, interval valued least square pre-nucleolus solution method is adopted and applied to specific cases. The results show that the algorithm of interval valued least squares pre-nucleolus solution is a more reasonable cooperative income allocation method for agricultural product supply chain. The method considers the principle of minimum dissatisfaction, reduces the fuzziness and uncertainty, and improves the enthusiasm of all participants in the agricultural product supply chain.
Research on the business model of distributed power trading based on blockchain technology
Authors: Lei Yadie , Liu Tianqin , Zhu Hongying
Published: February 2021

With the power system reform deepening, the distributed power trading in the market is prominent. Exploring the business model of distributed power trading has become an important issue to perfect the distributed power trading market. Firstly, the paper describes the current situation and the characteristics of the distributed power trading, summarizes the same characteristics between the distributed power trading and blockchain. Secondly, the paper analyses the interested participant of distributed power trading, clarify the value target of relevant participants, and then analyses the application of blockchain technology in distributed power trading through the literature method. Finally, the paper proposes to build a public service platform for distributed power trading based on blockchain technology, improves the principle of distributed power trading, standardizes the business trading process of distributed power trading, and then forms a kind of distributed power trading business model with multiple subjects participating in the competition. Furthermore, it can maximize the interests of the main participants and promote the distributed power trading fairer and more open.
Computational Study of The Stability of Turbulent Hydrogen Jet Flames with Methane Addition
Authors: Jaafar Syahirah Khaliesah , Hamid Mahar Diana
Published: February 2021

As the world predominately relies on fossil fuels to meet the current energy demands, the increasing consumption of it negatively impacts the environment. Thus, among constant search of a cleaner alternative fuel, hydrogen offers the greatest potential benefits in terms of energy supply and environmental impacts. However, hydrogen combustion is challenged by the difficulties in its production, storage, and end-use. Therefore, another method to enhance hydrogen combustion is to use hydrogen with methane addition as fuel. This study presents the effect of methane addition on the stability of hydrogen-methane flames by performing numerical analysis. In this study, the stability parameters such as lift-off height, lift-off velocity and blow-out velocity of hydrogen-methane jet flames were tested in three different mixing configurations. The first was to inject pure methane and pure hydrogen flames to form a jet flame. The second was to premix hydrogen and methane to form a jet flame. The third was to inject methane as an annular jet with hydrogen as the centre. All three different mixing configurations shows different results in terms of its stability parameters. From the first configuration, the lift-off height of pure methane is higher than pure hydrogen. From the second configuration, as methane concentration increases, the lift-off height increases but the lift-off velocity decreases. From the third configuration, the lift-off height highly depends on the velocity of annular jet flow but weakly depends on the central hydrogen jet flow. Generally, for all the mixing configurations, the lift-off height increases linearly with jet exit velocity.
Derivation of high-resolution orthophoto map from multirotor drone survey for application in infrastructure management
Authors: Mohamad NA , Azmy N , Mohamed Yusof L , Wahap M S
Published: February 2021

An orthophoto is a geometrically corrected aerial image that can be used in the same approach as map. It provides various geospatial information and therefore plays an important role in infrastructure management. This paper describes the methodology of an aerial survey using a multirotor drone and the processing of aerial images acquired from the survey to produce an orthophoto map. The survey work was carried out using Zenmuse X4S photogrammetric camera controlled by an autopilot multirotor drone at 200m above the ground. Optimal flight path for the autonomous mission was created and organized using the Map Pilot software. Five ground control points were laid within the survey area and their locations were determined using a real-time kinematic global navigation satellite system. Aerial images acquired from the survey were processed with the Pix4Dmapper photogrammetry software. The photogrammetric processing generated a 6 cm-resolution orthophoto map. The presented work demonstrates the practicality of multirotor drone survey and intelligent image processing for non-professionals in deriving high-resolution orthophoto map for application in infrastructure management.