bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual-layer collimator for improved spatial resolution in SPECT with CZT camera: an analytical and Monte Carlo study
Authors: Boutaghane Nasreddine , Hesse Michel , Bouzid Boualem , Zaidi Habib , Jamar François , Walrand Stephan 
Published: February 2022

Abstract

Purpose. Current hole matching pixel detector (HMPD) collimators for SPECT imaging exist in two configurations: one hole per pixel (1HMPD) or four holes per pixel (4HMPD). The aim of this study was to assess the performance of a dual-layer collimator made by stacking up these two collimator types (1H/4HMDP) for low- and medium energy gamma emitters. Method. Analytical equations describing geometrical efficiency and full width at half maximum (FWHM) of the 1H/4HMDP collimator were derived. In addition, a fast dedicated Monte Carlo (MC) code neglecting scattering and designed for the collimator geometry was developed to assess the collimator’s point spread function and to simulate planar and SPECT acquisitions. Results. A relative agreement between analytical equations and MC simulations better than 3% was observed for the efficiency and for the FWHM. The length of the two layers was optimized to get the best spatial resolution while keeping the geometrical efficiency equal to that of the 45 mm length 1HMPD collimator. An optimized combination of the 1H/4HMPD configuration with respective hole lengths of 20 and 13 mm has been derived. For source-collimator distances above 5 cm and equal collimator geometrical efficiency, the spatial resolution of this optimal 1H/4HMDP collimator supersedes that of the 45 mm length 1HMPD collimator, and that of the 19.1 mm length 4HMPD collimator. This improvement was observed in simulations of bar phantom planar images and of hot rods phantom SPECT. Remarkably, the spatial resolution was preserved along the whole radial range within the Jaszczak phantom. Conclusion. The 1H/4HMDP collimator is a promising solution for CZT SPECT imaging of low- and medium energy emitters.
Study on interfacial interactions and optoelectronic properties of MEH-PPV/SnO2 hetero-structure
Authors: Ashok Kumar Sangeetha , Shankar Jaya Seeli , Periyasamy Bhuvana K 
Published: February 2022

Abstract
The exciton dynamics in nanocomposites of tin oxide (SnO2) nanoparticles with a conjugated polymer (poly (2-methoxy-5-(2'-ethylhexyloxy) 1,4-phenylenevinylene) (MEH-PPV) have been investigated by steady-state, time-resolved photoluminescence (PL) spectroscopy and cyclic voltammetry (CV) analysis. SnO2 is an air-stable, optically transparent, electrically conductive deep valance band metal oxide which is suitable as an electron-accepting material in organic photovoltaics (PVs). Results reveals that SnO2 is an efficient electron-accepting material in comparison with titanium dioxide (TiO2) nanoparticles. Efficient charge separation takes places at SnO2/MEH-PPV interfaces when the polymer is excited, leading to enhancement in quenching of PL efficiency (10%) and shortening of the measured PL lifetime. In addition, the reduction in recombination rate of MEH-PPV/SnO2 nanocomposite show that the incorporation of nanoparticles in the polymer chain reduce disorders in the polymer chains. The blue-shift in the absorbance and emission maxima denotes that the process of in situ polymerization resulted in shortening of polymer chain conjugation. The electrochemical analysis for MEH-PPV/SnO2 nanocomposite shows increase in current density compared to MEH-PPV/TiO2 and pristine MEH-PPV. Moreover, the PL degradation experiments showed that MEH-PPV/SnO2 exhibited enhanced stability. MEH-PPV/SnO2 film attained 50% of the original intensity in ∼10 d, while pristine MEH-PPV and MEH-PPV/TiO2 exhibited half-life of ∼5 d when exposed to an ambient environment. The effect of TiO2 nanoparticles to stabilize MEH-PPV is though less important than that of SnO2. Thus MEH-PPV/SnO2 nanocomposite with enhanced absorbance, conductivity, stability and lowered bandgap formed an effective type-II band structure suitable for the PV active layer.
Metal-nitride dual-anode AlGaN/GaN heterostructure Schottky barrier diodes with tunable turn-on voltage and reverse leakage current
Authors: Wang Ting-Ting , Wang Xiao , Cui Zhen-Hai , Hong Wen , Li Yang , Li Liu-An , He Yue , Jia Mao , Guo Chen , Bai Li-Hua , Geng Ying-Zhao , Hao Yue , Ao Jin-Ping 
Published: February 2022

Abstract
AlGaN/GaN heterostructure lateral Schottky barrier diodes (SBDs) with TiN and NiN dual anode (DA) on sapphire substrates are investigated in this letter. The NiN anode with its high work-function leads to low leakage current and high breakdown voltage, while TiN anode with its low work-function determines the low turn-on voltage of the DA SBDs. Tunable turn-on voltage and leakage current are obtained in the DA SBDs by varying the radius of the TiN anode. As the radius of the TiN anode decreases from 80 to 8 μm, the turn-on voltage increases from 0.64 to 0.94 V, while the reverse leakage current decreases from 1 × 10−2 to 1 × 10−4 mA mm−1 at a reverse bias of −10 V and cathode–anode distance of 20 μm. The differential specific on-resistance at 100 mA mm−1 is 4.5 mΩ cm2 and barely changes with various radius of the TiN anode. A high breakdown voltage of 1.49 kV is achieved in the AlGaN/GaN DA SBDs with the radius of 80 μm of the TiN anode, obtaining a power Baliga’s figure of merit of 0.48 GW cm−2 at the cathode–anode distance of 20 μm. Besides, dynamic on-resistance increases less than 15% under pulse voltage bias at −60 V which may account on the good interface between metal nitrides and AlGaN, which is beneficial to the high frequency and high power application.
Review of the temporal stability of the magnetic field for ultra-high field superconducting magnets with a particular focus on superconducting joints between HTS conductors
Authors: Takeda Y , Maeda H , Ohki K , Yanagisawa Y 
Published: February 2022

Abstract
Superconducting magnets used in applications such as magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) require significant temporal magnetic field stability, which can be achieved when the MRI and NMR magnets are operated in the persistent current mode (persistent-mode) using superconducting joints. However, the ultra-high field MRI and NMR magnets are sometimes operated in the driven mode. Herein, we present an analysis of the temporal magnetic field drift and fluctuations observed for MRI and NMR magnets operating in the driven mode and an exploration of effective methods for stabilizing the temporal magnetic field fluctuations. In the last decade, substantial improvements have been achieved in superconducting joints between high-temperature superconductors (HTSs). These superconducting joints enable the development of persistent-mode ultra-high field magnets using HTS coils. Therefore, we herein review the superconducting joint technology for HTS conductors and describe the results of the persistent-mode operation achieved by a medium-field NMR magnet using an HTS coil. Particularly, the cutting-edge progress achieved concerning HTS superconducting joints, including joining methods, superconducting properties, and future prospects, is highlighted along with the issues that need to be addressed.
Enhanced radio-frequency performance of niobium films on copper substrates deposited by high power impulse magnetron sputtering
Authors: Arzeo M , Avino F , Pfeiffer S , Rosaz G , Taborelli M , Vega-Cid L , Venturini-Delsolaro W 
Published: February 2022

Abstract
We present a study of radio frequency properties of niobium films deposited on copper by two different approaches based on High Power Impulse Magnetron Sputtering, namely with a DC voltage biased substrate and with bipolar target voltage. Such approaches enable the synthesis of dense superconducting (SC) layers. The SC radio frequency losses of these films are characterized as a function of the applied RF magnetic field using a dedicated calorimetric method. We report on a significant reduction of the Q-slope phenomenon and the residual surface resistance in the characterized films, achieving similar values as those obtained on bulk niobium surfaces qualified with the same technique. Our results pave the way towards the realization of Nb/Cu coated accelerating cavities featuring a surface resistance 2–3 times lower than the state-of-the-art values at working frequencies of 400 and 800 MHz, making this technology even more appealing for future particle accelerators and colliders.
Stability of Captisol-enabled versus propylene glycol–based melphalan at room temperature and after refrigeration
Authors: Kawedia Jitesh D , Ramchandran Sumankalai , Liu Xiaoqian , Gulbis Alison M , Titus Mark , Bashir Qaiser , Qazilbash Muzaffar H , Champlin Richard E , Ciurea Stefan O 
Published: February 2022

Abstract

Purpose
To compare the chemical stability of Captisol-enabled (CE) melphalan (“CE-melphalan”; Evomela, Acrotech Biopharma LLC) and propylene glycol (PG)–based melphalan (“PG-melphalan”; Alkeran, GlaxoSmithKline) admixtures prepared with 0.9% sodium chloride injection in polyvinyl chloride (PVC) bags or reconstituted vials stored at room temperature (RT) and under refrigeration.

Methods
Lyophilized CE-melphalan and generic PG-melphalan were reconstituted to 5 mg/mL with 0.9% sodium chloride injection or manufacturer-supplied diluent, respectively. The reconstituted vials were then diluted to the desired concentrations with 0.9% sodium chloride injection in PVC bags and were stored at RT (23oC) or under refrigeration (4oC). Aliquots were withdrawn from the bags and reconstituted vials of CE-melphalan and PG-melphalan immediately after preparation and at predetermined time intervals. Melphalan concentrations were measured using a validated high-performance liquid chromatography method.

Results
CE-melphalan reconstituted in PVC bags at concentrations of 1 and 2 mg/mL was stable for 6 and 24 hours, respectively, at RT and for 8 and 24 hours, respectively, at 4oC. PG-melphalan reconstituted in bags at 1, 1.5, and 2 mg/mL was stable for 1, 2, and 2 hours, respectively, at RT and for 2, 4, and 4 hours, respectively, at 4oC. Reconstituted CE-melphalan vials were stable for 48 hours at both RT and 4oC, whereas PG-melphalan vials were stable for 6 hours at RT but formed precipitate within 2 hours at 4oC.

Conclusion
CE-melphalan remained stable longer than generic PG-melphalan under the test conditions. CE-melphalan at 2 mg/mL has 24-hour stability at RT and can be used for extended infusion times or may be compounded ahead of time. Reconstituted CE-melphalan vials are stable for 48 hours at both RT and 4oC.
Reducing healthcare disparities using multiple multiethnic data distributions with fine-tuning of transfer learning
Authors: Toseef Muhammad , Li Xiangtao , Wong Ka-Chun 
Published: February 2022

Abstract
Healthcare disparities in multiethnic medical data is a major challenge; the main reason lies in the unequal data distribution of ethnic groups among data cohorts. Biomedical data collected from different cancer genome research projects may consist of mainly one ethnic group, such as people with European ancestry. In contrast, the data distribution of other ethnic races such as African, Asian, Hispanic, and Native Americans can be less visible than the counterpart. Data inequality in the biomedical field is an important research problem, resulting in the diverse performance of machine learning models while creating healthcare disparities. Previous researches have reduced the healthcare disparities only using limited data distributions. In our study, we work on fine-tuning of deep learning and transfer learning models with different multiethnic data distributions for the prognosis of 33 cancer types. In previous studies, to reduce the healthcare disparities, only a single ethnic cohort was used as the target domain with one major source domain. In contrast, we focused on multiple ethnic cohorts as the target domain in transfer learning using the TCGA and MMRF CoMMpass study datasets. After performance comparison for experiments with new data distributions, our proposed model shows promising performance for transfer learning schemes compared to the baseline approach for old and new data distributation experiments.
Impact of Tamoxifen on Vorinostat-Induced Human Immunodeficiency Virus Expression in Women on Antiretroviral Therapy: AIDS Clinical Trials Group A5366, The MOXIE Trial
Authors: Scully Eileen P , Aga Evgenia , Tsibris Athe , Archin Nancie , Starr Kate , Ma Qing , Morse Gene D , Squires Kathleen E , Howell Bonnie J , Wu Guoxin , Hosey Lara , Sieg Scott F , Ehui Lynsay , Giguel Francoise , Coxen Kendyll , Dobrowolski Curtis , Gandhi Monica , Deeks Steve , Chomont Nicolas , Connick Elizabeth , Godfrey Catherine , Karn Jonathan , Kuritzkes Daniel R , Bosch Ronald J , Gandhi Rajesh T 
Published: February 2022

Abstract

Background
Biological sex and the estrogen receptor alpha (ESR1) modulate human immunodeficiency virus (HIV) activity. Few women have enrolled in clinical trials of latency reversal agents (LRAs); their effectiveness in women is unknown. We hypothesized that ESR1 antagonism would augment induction of HIV expression by the LRA vorinostat.

Methods
AIDS Clinical Trials Group A5366 enrolled 31 virologically suppressed, postmenopausal women on antiretroviral therapy. Participants were randomized 2:1 to receive tamoxifen (arm A, TAMOX/VOR) or observation (arm B, VOR) for 5 weeks followed by 2 doses of vorinostat. Primary end points were safety and the difference between arms in HIV RNA induction after vorinostat. Secondary analyses included histone 4 acetylation, HIV DNA, and plasma viremia by single copy assay (SCA).

Results
No significant adverse events were attributed to study treatments. Tamoxifen did not enhance vorinostat-induced HIV transcription (between-arm ratio, 0.8; 95% confidence interval [CI], .2–2.4). Vorinostat-induced HIV transcription was higher in participants with increases in H4Ac (fold increase, 2.78; 95% CI, 1.34–5.79) vs those 9 who did not (fold increase, 1.04; 95% CI, .25–4.29). HIV DNA and SCA plasma viremia did not substantially change.

Conclusions
Tamoxifen did not augment vorinostat-induced HIV RNA expression in postmenopausal women. The modest latency reversal activity of vorinostat, postmenopausal status, and low level of HIV RNA expression near the limits of quantification limited assessment of the impact of tamoxifen. This study is the first HIV cure trial done exclusively in women and establishes both the feasibility and necessity of investigating novel HIV cure strategies in women living with HIV.

Clinical Trials Registration
NCT03382834.
Utility of Epstein–Barr Virus DNA in Nasopharynx Swabs as a Reflex Test to Triage Seropositive Individuals in Nasopharyngeal Carcinoma Screening Programs
Authors: Chen Geng Hang , Liu Zhiwei , Yu Kelly J , Coghill Anna E , Chen Xiao Xia , Xie Shang Hang , Lin Dong Feng , Huang Qi Hong , Lu Yu Qiang , Ling Wei , Lin Chu Yang , Lu Zi Jian , Fan Yu Ying , Tang Lin Quan , Sampson Joshua N , Li Hui , King Ann D , Middeldorp Jaap M , Hildesheim Allan , Cao Su Mei 
Published: February 2022

Abstract

Background
Epstein–Barr virus (EBV) DNA detection in the nasopharynx is considered a biomarker for nasopharyngeal carcinoma (NPC). We evaluated its performance as a reflex test to triage EBV seropositives within an NPC screening program in China.

Methods
The study population was embedded within an ongoing NPC screening trial and included 1111 participants who screened positive for anti-EBV VCA (antibodies against EBV capsid antigens)/EBNA1 (EBV nuclear antigen1)-IgA antibodies (of 18 237 screened). Nasopharynx swabs were collected/tested for EBNA1 gene EBV DNA load. We evaluated performance of EBV DNA in the nasopharynx swab as a reflex test to triage EBV serological high-risk (those referred to endoscopy/MRI) and medium-risk (those referred to accelerated screening) individuals.

Results
By the end of 2019, we detected 20 NPC cases from 317 serological high-risk individuals and 4 NPC cases from 794 medium-risk individuals. When used to triage serological high-risk individuals, nasopharynx swab EBV DNA was detected in 19/20 cases (positivity rate among cases: 95.0%; 95% CI, 75.1%–99.9%), with a referral rate of 63.4% (201/317, 95% CI, 57.8%–68.7%) and NPC detection rate among positives of 9.5% (19/201, 95% CI, 5.8%–14.4%). The performance of an algorithm that combined serology with triage of serology high-risk individuals using EBV DNA testing yielded a sensitivity of 72.4% (95% CI, 3.0%-81.4%) and specificity of 97.6% (95% CI, 97.2%-97.9%). When used to triage EBV serological medium-risk individuals, the positivity rate among cases was 75.0% (95% CI, 19.4%-99.4%), with a referral rate of 61.8% (95% CI, 58.4%-65.2%) and NPC detection rate among positives of 0.6% (95% CI, 0.1%-1.8%).

Conclusions
Nasopharynx swab EBV DNA showed promise as a reflex test to triage serology high-risk individuals, reducing referral by ca. 40% with little reduction in sensitivity compared to a serology-only screening program.
A Self-Stabilizing Distributed Algorithm for the Generalized Dominating Set Problem With Safe Convergence
Authors: Kobayashi Hisaki , Sudo Yuichi , Kakugawa Hirotsugu , Masuzawa Toshimitsu 
Published: February 2022

Abstract
A self-stabilizing distributed algorithm is guaranteed eventually to reach and stay at a legitimate configuration regardless of the initial configuration of a distributed system. In this paper, we propose the generalized dominating set problem, which is a generalization of the dominating set and $k$-redundant dominating set problems. In the generalized dominating set we propose in this paper, each node $P_{i}$ is given its set of domination wish sets, and a generalized dominating set is a set of nodes such that each node is contained in the set or has a wish set in which all its members are in the set. We propose a self-stabilizing distributed algorithm for finding a minimal generalized dominating set in an arbitrary network under the unfair distributed daemon. The proposed algorithm converges in $O(n^{3}m)$ steps and $O(n)$ rounds, where $n$ (resp., $m$) is the number of nodes (resp., edges). Furthermore, it has the safe convergence property with safe convergence time in $O(1)$ rounds. The space complexity of the proposed algorithm is $O(\Delta \log n)$ bits per node, where $\Delta $ is the maximum degree of nodes.
Modelling and Predictive Analytics of COVID-19 Transmission Using Gustafson–Kessel Fuzzy Clustering Approach
Authors: Vijayakarthick M , Sivaraman E , Sathishbabu S , Vinoth N , Sivaraj S N 
Published: February 2022

Abstract
A novel Corona virus disease 2019 (COVID-19) outbreak is declared as the international public health emergency concern by the World Health Organization in the month of March 2020. This viral disease invented from China in the month of December 2019 has previously caused havoc around the world, including India. In this paper, efficient mathematical models using Gustafson–Kessel fuzzy clustering approach for the transmission of the COVID-19 are developed by considering the actual reported cases in the state of Tamil Nadu, India. The results proved a good concord between the reported data and the estimated data given by the proposed models. Moreover, the developed models are also capable to predict the requirements of beds in hospitals on the month of August 2020 in Tamil Nadu, India. Also, this work suggests strictly implementing/extending the complete lockdown for at least 21 days in the month of August 2020 and immediate separation of infected cases are the positive steps to reduce the spread of novel corona virus in Tamil Nadu state, India.
Decentralized Data Flows for the Functional Scalability of Service-Oriented IoT Systems
Authors: Arellanes Damian , Lau Kung-Kiu , Sakellariou Rizos 
Published: February 2022

Abstract
Horizontal and vertical scalability have been widely studied in the context of computational resources. However, with the exponential growth in the number of connected objects, functional scalability (in terms of the size of software systems) is rapidly becoming a central challenge for building efficient service-oriented Internet of Things (IoT) systems that generate huge volumes of data continuously. As systems scale up, a centralized approach for moving data between services becomes infeasible because it leads to a single performance bottleneck. A distributed approach avoids such a bottleneck, but it incurs additional network traffic as data streams pass through multiple mediators. Decentralized data exchange is the only solution for realizing totally efficient IoT systems, since it avoids a single performance bottleneck and dramatically minimizes network traffic. In this paper, we present a functionally scalable approach that separates data and control for the realization of decentralized data flows in service-oriented IoT systems. Our approach is evaluated empirically, and the results show that it scales well with the size of IoT systems by substantially reducing both the number of data flows and network traffic in comparison with distributed data flows.
Paternal grandmother’s smoking in pregnancy is associated with extreme aversion to bitter taste in their grandchildren
Authors: Golding Jean , Pembrey Marcus E , Gregory Steven , Suderman Matthew , Iles-Caven Yasmin , Northstone Kate 
Published: February 2022

Abstract
Although there are many examples in the experimental literature of an environmental exposure in one generation impacting the phenotypes of subsequent generations, there are few studies that can assess whether such associations occur in humans. The Avon Longitudinal Study of Parents and Children (ALSPAC) has, however, been able to determine whether there are associations between grandparental exposures and their grandchildren’s development. Several of our studies, including sensitivity to loud noise, have shown associations between a grandmother smoking in pregnancy and the phenotype of the grandchild. These results were mostly specific to the sex of the grandchild and to whether the prenatal (i.e. during pregnancy) smoking occurred in the maternal or paternal grandmother. Here, we have used ancestral data on prenatal smoking among the grandmothers of the ALSPAC index children to examine possible effects on the grandchild’s ability to detect the bitter taste of PROP (6 n-propylthiouracil), distinguishing between the 10% deemed ‘extreme tasters’, and the rest of the population (total N = 4656 children). We showed that grandchildren whose paternal (but not maternal) grandmothers had smoked in pregnancy were more likely than those of non-smoking grandmothers to be extreme tasters [odds ratio (OR) 1.28; 95% confidence interval (CI) 1.03, 1.59] and that this was more likely in granddaughters (OR 1.42; 95% CI 1.03, 1.95) than grandsons (OR 1.18; 95% CI 0.88, 1.60). This pattern of association between paternal foetal exposure and the granddaughter’s development has been found with several other outcomes, suggesting that investigations should be undertaken to investigate possible mechanisms.