bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiscale mechanics of tissue‐engineered cartilage grown from human chondrocytes and human‐induced pluripotent stem cells
Authors: Middendorf Jill M. , Diamantides Nicole , Shortkroff Sonya , Dugopolski Caroline , Kennedy Stephen , Cohen Itai , Bonassar Lawrence J.
Published: March 2020

Tissue‐engineered cartilage has shown promising results in the repair of focal cartilage defects. However, current clinical techniques rely on an extra surgical procedure to biopsy healthy cartilage to obtain human chondrocytes. Alternatively, induced pluripotent stem cells (iPSCs) have the ability to differentiate into chondrocytes and produce cartilaginous matrix without the need to biopsy healthy cartilage. However, the mechanical properties of tissue‐engineered cartilage with iPSCs are unknown and might be critical to long‐term tissue function and health. This study used confined compression, cartilage on glass tribology, and shear testing on a confocal microscope to assess the macroscale and microscale mechanical properties of two constructs seeded with either chondrocyte‐derived iPSCs (Ch‐iPSCs) or native human chondrocytes. Macroscale properties of Ch‐iPSC constructs provided similar or better mechanical properties than chondrocyte constructs. Under compression, Ch‐iPSC constructs had an aggregate modulus that was two times larger than chondrocyte constructs and was closer to native tissue. No differences in the shear modulus and friction coefficients were observed between Ch‐iPSC and chondrocyte constructs. On the microscale, Ch‐iPSC and chondrocyte constructs had different depth‐dependent mechanical properties, neither of which matches native tissue. These observed depth‐dependent differences may be important to the function of the implant. Overall, this comparison of multiple mechanical properties of Ch‐iPSC and chondrocyte constructs shows that using Ch‐iPSCs can produce equivalent or better global mechanical properties to chondrocytes. Therefore, iPSC‐seeded cartilage constructs could be a promising solution to repair focal cartilage defects. The chondrocyte constructs used in this study have been implanted into humans for clinical trials. Therefore, Ch‐iPSC constructs could also be used clinically in place of the current chondrocyte construct.
Pressure dependence of micro‐Raman mass spectrometry for carbon isotopic composition of carbon dioxide fluid
Authors: Yokokura Lena , Hagiwara Yuuki , Yamamoto Junji
Published: March 2020

Micro‐Raman spectroscopy can find the carbon isotopic ratio of CO2 fluid from the ratio of intensity or area of a 13CO2 peak to that of a 12CO2 peak. We examined the precisions of carbon isotopic ratios (δ13C) of CO2 at constant room temperature and pressure of 10–150 MPa. Measurement of the intensity ratio has precision of 2.8–8.7‰, which is better than that of the area ratio of 4.5–14.7‰. We also investigated the pressure dependence of the Raman intensity ratios and area ratio by changing fluid pressure. When changing fluid pressure from 10 to 150 MPa, the ratios of intensity and area both show negative correlation with fluid pressure (CO2 density). Pressures of two types affect the Raman spectrum of CO2 peaks, affecting the peak position and peak shape. To evaluate effects on the peak position, we repeatedly measured the intensity ratio at constant CO2 pressure (10 MPa) with movement of the grating center position, which is defined as the center value of the analyzed wave number range. Although we moved the grating center position from 1,248.5 to 1,251.5 cm−1, no significant correlation was observed for either ratio of intensity or area. The pressure effect on the ratios can be corrected by ascertaining the CO2 pressure. Combination with the Raman spectroscopic barometry for CO2 enables analyses of δ13C of CO2 respectively using the intensity ratio and the area ratio of CO2 Raman peaks within 8.7 and 14.7‰.
Fast and efficient immunoaffinity column cleanup and liquid chromatography–tandem mass spectrometry method for the quantitative analysis of aflatoxins in baby food and feeds
Authors: AlFaris Nora Abdullah , Wabaidur Saikh Mohammad , Alothman Zeid Abdullah , Altamimi Jozaa Zaidan , Aldayel Tahany Saleh
Published: March 2020

An ultra high performance liquid chromatography‐tandem mass spectrometric method has been developed for the highly sensitive and selective determination of regulated aflatoxins. The extraction of aflatoxins from baby food matrices were performed using liquid–liquid extraction procedure followed by immunoaffinity column cleanup. The higher sensitivity for the determination of target aflatoxins was fulfilled by applying a preconcentration step with immunoaffinity columns after acetonitrile–water extraction. The enhanced selectivity was attained with the triple quadrupole mass analyzer operated in electrospray positive ionization mode. Method validation was tested in five different baby food matrices by recovery experiments. Satisfactory recoveries, between 92 and 103%, with relative standard deviations lower than 8% were achieved in all the tested matrices. The proposed method was found to be specific as no interference peaks were observed for blank samples. The limit of detection of the method was found to be in the range of 0.003–0.008 ng/mL. The validated method was fruitfully applied to the screening of aflatoxins in baby foods and feeds sample retailed in local markets of Riyadh, Saudi Arabia. The obtained levels of all analyzed aflatoxins were below the regulation limits set by European Agency.
Phase Control Behavior of Lateral Polymer Photodetectors Using Strong Aggregation Bulk Heterojunction Film
Authors: Han Tao , Liu Qiao , Guo Yanxi , Jin Gui , Ding Shufang , Yao Min , Jiang Chunzhi , Wang Huanyou , Huang Xiaoyi , Chang Fa
Published: March 2020

The aggregation behavior of polymers can ultimately have a significant impact on the performance of polymer photodetectors depends mainly on the main solvent, solvent additive, thermal annealing treatment, and so on. In this work, a phase control behavior of lateral polymer photodetectors (L‐PPDs) is realized by changing the acceptor concentration or introducing 1,8‐diiodooctane (DIO) in strong aggregation of bulk heterojunction (BHJ) films, which can effectively regulate the minority carriers trapping under high PC61BM ratio. Additionally the responsivity (R), gain (G) and specific detectivity (D*) value of the L‐PPDs can reach 94.4 A W−1, 289.7, and 1.33 × 1014 Jones under 0.0031 mW cm−2 @405 nm, respectively. The structure of the L‐PPDs is optimized as quartz/ PMMA (30 nm)/ PffBT4T‐2OD:PC61BM (D/A ratio = 1:1.2)/ Ag–Ag electrodes. Furthermore, the phase separation of the thin films is promoted by introducing 3% DIO, resulting in a clear increase of response speed (fall time is about tenfold faster than that of the control device), and an improved switching performance about 60‐fold higher under strong light (10.42 mW cm−2). This research represents an important step forward in the fabrication of high‐performance polymer photodetectors, which show promising application potential.
An investigation of the regional correlation gradients between Euro‐Atlantic atmospheric teleconnections and winter solar short wave radiation in northwest Europe
Authors: Correia João M. , McDermott Frank , Sweeney Conor , Doddy Eadaoin , Griffin Seánie
Published: March 2020

Increased use of solar photovoltaic electricity requires a better understanding of the impact of large‐scale atmospheric teleconnections on incident short wave (SW) solar radiation. Our focus is on the relationship between winter (December to February) SW radiation in northwest Europe and the dominant Euro‐Atlantic atmospheric teleconnection patterns using multiple multi‐decadal observational and gridded reanalysis datasets, with a focus on the islands of Ireland and Britain. Our study reveals that the previously reported west–east seesaw in the correlation pattern between the winter North Atlantic Oscillation (NAO) index and winter SW radiation across the United Kingdom is complex, involving several zonal changes in the sign of the NAO–SW correlations (multiple seesaws). By comparison with the NAO, the east Atlantic pattern exerts only a weak control on winter SW radiation across the United Kingdom and Ireland, although in the western part of the Iberian Peninsula and adjacent Atlantic Ocean significant positive correlations occur. High values of the Scandinavian pattern index result in higher than average winter SW radiation in much of northern Europe, although it is evident that some regions (e.g. northeast England, east Scotland and the adjacent North Sea area) exhibit the opposite behaviour. Inter‐seasonal variations in the dominant atmospheric flow and moisture transport directions, steered by large‐scale atmospheric pressure patterns, combined with orographic uplift and rainout effects on the windward side of hills and mountains are interpreted to be the physical drivers of the observed zonal variations and correlation sign reversals between winter SW anomalies and the NAO index.
Imaging quality of PROPELLER diffusion‐weighted MR imaging and its diagnostic performance in distinguishing pleomorphic adenomas from Warthin tumors of the parotid gland
Authors: Liu Yi‐Jui , Lee Yi‐Hsiung , Chang Hing‐Chiu , Chung Hsiao‐Wen , Wang Chih‐Wei , Juan Cheng‐Hsuan , Chu Yueng‐Hsiang , Lee Jih‐Chin , Juan Chun‐Jung
Published: March 2020

The aim of this study was to evaluate the imaging quality and diagnostic performance of fast spin echo diffusion‐weighted imaging with periodically rotated overlapping parallel lines with enhanced reconstruction (FSE‐PROP‐DWI) in distinguishing parotid pleomorphic adenoma (PMA) from Warthin tumor (WT). This retrospective study enrolled 44 parotid gland tumors from 34 patients, including 15 PMAs and 29 WTs with waived written informed consent. All participants underwent 1.5 T diffusion‐weighted imaging including FSE‐PROP‐DWI and single‐shot echo‐planar diffusion‐weighted imaging (SS‐EP‐DWI). After imaging resizing and registration among T2WI, FSE‐PROP‐DWI and SS‐EP‐DWI, imaging distortion was quantitatively analyzed by using the Dice coefficient. Signal‐to‐noise ratio and contrast‐to‐noise ratio were qualitatively evaluated. The mean apparent diffusion coefficient (ADC) of parotid gland tumors was calculated. Wilcoxon signed‐rank test was used for paired comparison between FSE‐PROP‐DWI versus SS‐EP‐DWI. Mann–Whitney U test was used for independent group comparison between PMAs versus WTs. Diagnostic performance was evaluated by receiver operating characteristics curve analysis. P < 0.05 was considered statistically significant. The Dice coefficient was statistically significantly higher on FSE‐PROP‐DWI than SS‐EP‐DWI for both tumors (P < 0.005). Mean ADC was statistically significantly higher in PMAs than WTs on both FSE‐PROP‐DWI and SS‐EP‐DWI (P < 0.005). FSE‐PROP‐DWI and SS‐EP‐DWI successfully distinguished PMAs from WTs with an AUC of 0.880 and 0.945, respectively (P < 0.05). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy in diagnosing PMAs were 100%, 69.0%, 62.5%, 100% and 79.5% for FSE‐PROP‐DWI, and 100%, 82.8%, 75%, 100% and 88.6% for SS‐EP‐DWI, respectively. FSE‐PROP‐DWI is useful to distinguish parotid PMAs from WTs with less distortion of tumors but lower AUC than SS‐EP‐DWI.
Study of the nanostructure of γ‐irradiated high‐density polyethylene/carbon black composite and its durability as geomembrane
Authors: Taha Howayda G. , Mohamed Hamdy F. M.
Published: March 2020

The degradation of the nearby generation of high‐density polyethylene (HDPE) loaded with 2.5% of carbon black (CB) content (ie, HDPE/CB composites) is studied experimentally with the end goal of radiation safety applications. The impact of various γ‐irradiation doses in the air on the nanostructure of free volume and durability has been researched. The free volume was evaluated utilizing the positron annihilation lifetime (PAL) technique while the durability was contemplated by measuring the mechanical properties such as strain, elongation at break, and tear resistance. The electrical conductivity was explored to demonstrate the impact of the irradiation dose on the conductivity of the samples. Surface morphology studies using a scanning electron microscope (SEM) showed the surface fracture of HDPE/CB composites for unirradiated and irradiated samples. The surface roughness of the HDPE/CB GMs increases with increasing the irradiation dose. Among various uses of HDPE/CB composites, sheets are liners of dumps used to dispose of interim storage for Low and Medium Level Waste of NORMs and TENORMs. HDPE Geomembrane liners proved its utilization from the results of present research of electrical, mechanical tests, and SEM morphology to have the required resistance to weather conditions.
Validation of algorithms to identify adverse perinatal outcomes in the Medicaid Analytic Extract database
Authors: He Mengdong , Huybrechts Krista F. , Dejene Sara Z. , Straub Loreen , Bartels Devan , Burns Stacey , Combs David J. , Cottral Jennifer , Gray Kathryn J. , Manning‐Geist Beryl L. , Mogun Helen , Reimers Rebecca M. , Hernandez‐Diaz Sonia , Bateman Brian T.
Published: March 2020

Background

The Medicaid Analytic eXtract (MAX) is a health care utilization database from publicly insured individuals that has been used for studies of drug safety in pregnancy. Claims‐based algorithms for defining many important maternal and neonatal outcomes have not been validated.

Objective

To validate claims‐based algorithms for identifying selected pregnancy outcomes in MAX using hospital medical records.

Methods

The medical records of mothers who delivered between 2000 and 2010 within a single large healthcare system were linked to their claims in MAX. Claims‐based algorithms for placental abruption, preeclampsia, postpartum hemorrhage, small for gestational age, and noncardiac congenital malformation were defined. Fifty randomly sampled cases for each outcome identified using these algorithms were selected, and their medical records were independently reviewed by two physicians to confirm the presence of the diagnosis of interest; disagreements were resolved by a third physician reviewer. Positive predictive values (PPVs) and 95% confidence intervals (CIs) of the claims‐based algorithms were calculated using medical records as the gold standard.

Results

The linked cohort included 10,899 live‐birth pregnancies. The PPV was 92% (95% CI, 82%‐97%) for placental abruption, 82% (95% CI, 70%‐91%) for preeclampsia, 74% (95% CI, 61%‐85%) for postpartum hemorrhage, 92% (95% CI, 82%‐97%) for small for gestational age, and 86% (95% CI, 74%‐94%) for noncardiac congenital malformation.

Conclusions

Across the perinatal outcomes considered, PPVs ranged between 74% and 92%. These PPVs can inform bias analyses that correct for outcome misclassification.
Evaluating the performance of school psychologists: Current status and future directions with a 360‐degree evaluation process
Authors: Morrison Julie Q. , Hutchinson Courtney E. , Talapatra Devadrita
Published: March 2020

The purpose of this article is twofold: (a) to present the results of a study examining the current status of performance evaluations for school psychologist and (b) to use those findings to inform future directions. A content analysis of a national sample of 36 performance appraisal rubrics was conducted to examine their alignment with the professional standards established by the National Association of School Psychologists (NASP). Among the rubrics reviewed, 88.9% featured eight or more of the NASP domains of practice, yet only 56% of the rubrics featured all 10 domains, suggesting variability in the degree to which the rubrics aligned with the standards of practice, particularly for rubrics developed at the district‐level. The results of this study informed the development of a 360‐evaluation process based on the Framework for Personnel Evaluation of School Psychologists Utilizing the NASP Practice Model and Morrison's four key principles for evaluating the performance of school psychologists.
A Sensitive “Optical Nose” for Detection of Volatile Organic Molecules Based on Au@MOFs Nanoparticle Arrays through Surface‐Enhanced Raman Scattering
Authors: Men Dandan , Feng Sujuan , Liu Guangqiang , Hang Lifeng , Zhang Tao
Published: March 2020

Surface‐enhanced Raman scattering (SERS) is an effective technique for detecting toxic gas and volatile organic molecules (VOMs); however, recent SERS‐based gas sensors have disadvantages and lack an effective approach to capture toxic gas and insufficient reproducibility of SERS substrates. Herein, a facile strategy is developed to integrate metal‐organic frameworks with Au nanoparticle (NP) arrays to form Au@ZIF‐8 NP arrays, which can be used as an “optical nose” based on SERS to detect toxic VOMs with good reproducibility and sensitivity. Toluene as a target molecule is recognized at ppm levels by the Au@ZIF‐8 NP arrays in situ. And the analytical enhancement factor of Au@ZIF‐8 NP arrays for toluene is about 1.2 × 105. Importantly, this SERS substrate can also detect the 1‐butanol molecule, which provides an idea for designing a universal VOM sensor. In addition, the coating method of the ZIF‐8 shell can be extended to synthetize various NPs@ZIF‐8 core–shell composites, such as Au nanospheres@ZIF‐8, Au@Ag nanorods@ZIF‐8, PS microspheres@ZIF‐8, and Fe2O3 microellipsoids@ZIF‐8 composites.
2D CdO‐Based Heterostructure as a Promising Visible Light Water‐Splitting Photocatalyst
Authors: Wang Guangzhao , Zhi Yan , Xia Liangping , Chang Junli , Yuan Binfang , Guo Xiaogang , Li Yadong , Xiao Shuyuan , Yuan Hongkuan
Published: March 2020

A 2D CdO/g‐C3N4 heterostructure (CdCHT) is designed as a potential photocatalyst. Using first‐principle calculations, it is found that CdCHT is a type‐II heterostructure, which promotes the separation of photoinduced carriers and thereby facilitates water reduction and oxidation at different layers. Visible light‐absorption ability is obviously improved compared with the constituent single layers. Especially, the band edge alignments of CdCHTs with biaxial strains satisfy water redox energy levels within the pH range between 4.3 and 12.3, which ensures the occurrence of the water redox reaction. Furthermore, the calculation of free energy proves the high hydrogen production activity of CdCHT. These factors render CdCHT to be suitable for water‐splitting photocatalysis.
Ultraviolet Stimulated Emission in AlGaN Layers Grown on Sapphire Substrates Using Ammonia and Plasma‐Assisted Molecular Beam Epitaxy
Authors: Rzheutski Mikalai V. , Lutsenko Evgenii V. , Vainilovich Aliaksei G. , Svitsiankou Illia E. , Nahorny Aliaksei V. , Yablonskii Gennadii P. , Zubialevich Vitaly Z. , Petrov Stanislav I. , Alexeev Alexey N. , Nechaev Dmitrii V. , Jmerik Valentin N.
Published: March 2020

Ammonia and plasma‐assisted (PA) molecular beam epitaxy modes are used to grow AlN and AlGaN epitaxial layers on sapphire substrates. It is determined that the increase in the thickness of the AlN buffer layer grown by ammonia molecular beam epitaxy (MBE) from 0.32 to 1.25 μm results in the narrowing of 101 X‐Ray rocking curves (XRCs), whereas no clear effect on the 002 XRC width is observed. It is shown that strong GaN decomposition during growth by ammonia MBE causes AlGaN surface roughening and compositional inhomogeneity, which leads to deterioration of its lasing properties. AlGaN layers grown by ammonia MBE at an optimized temperature demonstrate stimulated emission (SE) which peaks at λ = 330, 323, 303, and 297 nm, with SE threshold values of 0.7, 1.1, 1.4, and 1.4 MW cm−2, respectively. In comparison with these, AlGaN layers grown using PA MBE pulsed modes (migration‐enhanced epitaxy, metal‐modulated epitaxy, and droplet elimination by thermal annealing) show SE with a relatively low threshold (0.8 MW cm−2) at a considerably shorter wavelength of λ = 267 nm.
Solution‐Processable Anode Double Buffer Layers for Inverted Polymer Solar Cells
Authors: Cominetti Alessandra , Serrano Giulia , Savoini Alberto , Carbonera Chiara , Melchiorre Fabio , Perucchini Sara , Congiu Annalisa , Corso Gianni , Barbieri Riccardo , Trippodo Elisa , Caneschi Andrea , Po Riccardo
Published: March 2020

Although organic solar cells have surpassed the 17% power conversion efficiency threshold, commercial modules efficiencies are only around 4–5%. One of the reason is the lack of effective solution‐processable hole transport materials that are a key element for the scale‐up on roll‐to‐roll printing equipments and the commercial development. Herein, a class of novel vanadium and molybdenum polyoxometallate salts are developed that, alone or in combination with a traditional poly(ethylene‐3,4‐dioxytiophene):poly(styrene sulfonate) (PEDOT:PSS) layer, can be used as anodic buffer layer in inverted polymer solar cells. These materials exhibit work function values around 5.8 eV that match well with highest occupied molecular orbital energies of typical polymer donors. They are tested with different widely used active systems, including PTB7:PC71BM, PV2000:PCBM, and PffBT4T:PC71BM. Vanadium and molybdenum polyoxometallate can be deposited from solutions and, contrary to PEDOT:PSS used alone, do not cause a drop of performances compared with evaporated molybdenum oxide (e‐MoOx); on the contrary, in the best cases they achieve similar performances to e‐MoOx. Slot‐die‐coated PV2000:PCBM solar cells on flexible substrate achieve a remarkable power conversion efficiency of almost 7.6%.
Multifunctionalized Polyamides Prepared by Facile Ugi Reaction as Thermosensitive, Biocompatible and Antibacterial Biomaterials
Authors: Liu Na , Fu Congcong , Zhang Qi , Zhao Ronghui , Sun Zhuxing , Zhang Pengfei , Ding Lan , Deng Kuilin
Published: March 2020

A series of multifunctionalized polyamides were facilely prepared by Ugi four‐component polymerization (Ugi‐4CP) in one‐pot method at room temperature using several diacids, aldehydes, 1,4 bis‐(3‐aminopropyl) piperazine and tert‐butyl isocyanide as monomers. The simple combination of monomers in Ugi‐4CP led to formation of nine thermosensitive polyamides in water, and their lower critical solution temperatures (LCSTs) were in range of 13.1‐70.1°C. The LCSTs for the subsequently‐quaternized polyamides (PBA‐800‐Br, PIA‐800‐Br and PCA‐800‐Br) were easily readjusted to the desired value in the inorganic salt solutions. PBA‐800‐Br and PIA‐800‐Br exhibited high antibacterial activity against Gram negative E. coli and Gram positive S. aureus. Confocal laser scanning microscope (CLSM) manifested the clear internalization into the cellular inside for the fluorescent molecule‐labelled polyamides. After 24–72 hours of incubation in polyamide solution, the viability rate of HeLa cells reached up to 80–141%, indicating the excellent biocompatibility. In conclusion, the thermosensitive, antibacterial and biocompatible polyamides have great potential to be used as biomaterials.
Guidelines for evaluating bug‐assignment research
Authors: Sajedi‐Badashian Ali , Stroulia Eleni
Published: March 2020

Bug assignment is the task of ranking candidate developers in terms of their potential competence to fix a bug report. Numerous methods have been developed to address this task, relying on different methodological assumptions and demonstrating their effectiveness with a variety of empirical studies with numerous data sets and evaluation criteria. Despite the importance of the subject and the attention it has received from researchers, there is still no unanimity on how to validate and comparatively evaluate bug‐assignment methods and, often times, methods reported in the literature are not reproducible.

In this paper, we first report on our systematic review of the broad bug‐assignment research field. Next, we focus on a few key empirical studies and review their choices with respect to three important experimental‐design parameters, namely, the evaluation metric(s) they report, their definition of who the real assignee is, and the community of developers they consider as candidate assignees.

The substantial variability on these criteria led us to formulate a systematic experiment to explore the impact of these choices. We conducted our experiment on a comprehensive data set of bugs we collected from 13 long‐term open‐source projects, using a simple Tf‐IDf similarity metric. On the basis of our arguments and/or experiments, we provide useful guidelines for performing further bug‐assignment research. We conclude that mean average precision (MAP) is the most informative evaluation metric, the developer community should be defined as “all the project members,” and the real assignee should be defined as “any developer who worked toward fixing a bug.”
Mitigation of radiation‐induced hematopoietic system injury by melatonin
Authors: Amini Peyman , Ashrafizadeh Milad , Motevaseli Elahe , Najafi Masoud , Shirazi Alireza
Published: March 2020

Background

Increased risks of exposure to accidental radiation events are a concern in today's world. Radiation terror, nuclear explosion, as well as accidental exposure to radioactive sources in some industries pose a threat to the life of exposed persons. Studies have been conducted using some low‐toxic agents to mitigate radiation toxicity and increase survival probability for exposed people. In the current study, we aimed to show the mitigation of radiation‐induced mortality and bone marrow toxicity using postirradiation treatment with melatonin.

Method

Mice whole bodies were exposed to 4 or 7 Gy radiation followed by treatment with melatonin after 24 hours. Survival of mice with or without melatonin, the levels of peripheral cells, transforming growth factor (TGF)‐β and 8‐hydroxy‐2' ‐deoxyguanosine (8‐OHdG) in the bone marrow, as well as the expression of NADPH oxidase (NOX)2 and NOX4 in bone marrow cells were evaluated.

Results

Whole body irradiation led to mortality 30 days after irradiation. However, melatonin treatment reduced mortality. Irradiation also showed severe reduction of lymphocytes, platelets, and red blood cells. The expressions of NOX2 and NOX4, in addition to TGF‐β level, were increased after exposure to radiation. Melatonin ameliorated the increased levels of these factors and improved the number of blood cells.

Conclusions

Melatonin showed ability to mitigate radiation‐induced hematopoietic system toxicity and also increased survival rate. These results suggest that melatonin could be a potential mitigator for accidental radiation events.
Generalised μ-τ symmetries and calculable gauge kinetic and mass mixing in $$ \mathrm{U}{(1)}_{L_{\mu }-{L}_{\tau }} $$ models
Authors: Joshipura Anjan S. , Mahajan Namit , Patel Ketan M.
Published: March 2020

Abstract

Extensions of the standard model with a U(1) gauge symmetry contain gauge invariant kinetic mixing, sin χ, and gauge non-invariant mass mixing, δM2, between the hypercharge and the new gauge boson Z′. These represent a priori incalculable but phe- nomenologically important parameters of the theory. They become calculable if there exist spontaneously or softly broken symmetries which forbid them at tree level but allow their generation at the loop level. We discuss various symmetries falling in this category in the context of the gauged Lμ − Lτ models and their interplay with lepton mixing. It is shown that one gets phenomenologically inconsistent lepton mixing parameters if these symmetries are exact. Spontaneous breaking of these symmetries can lead to consistent lepton mixing and also generates finite and calculable values of these parameters at one or two loop order depending on the underlying symmetry. We calculate these parameters in two specific cases: (i) the standard seesaw model with μ-τ symmetry broken by the masses of the right-handed neutrinos and (ii) in a model containing a pair of vectorlike charged leptons which break μ-τ symmetry. In case (i), the right-handed neutrinos are the only source of gauge mixing. The kinetic mixing parameters are suppressed and vanish if the right-handed neutrinos decouple from the theory. In contrast, there exists a finite gauge mixing in case (ii) which survives even when the masses of vectorlike leptons are taken to infinity, exhibiting non-decoupling behaviour. The seesaw model discussed here represents a complete framework with practically no kinetic mixing and hence can survive a large number of experimental probes used to rule out specific ranges in the coupling g′ and mass $$ {M}_{Z^{\prime }} $$

M

Z
′

. The model can generate non-universality in tau decays, which can be tested in future experiments.
CTBTO’s Data and Analysis Pertaining to the Search for the Missing Argentine Submarine ARA San Juan
Authors: Nielsen Peter L. , Zampolli Mario , Le Bras Ronan , Mialle Pierrick , Bittner Paulina , Poplavskiy Alexander , Rozhkov Mikhail , Haralabus Georgios , Tomuta Elena , Bell Randy , Grenard Patrick , Taylor Tammy , Özel Nurcan Meral
Published: March 2020

The Argentine submarine ARA (Armada de la República Argentina) San Juan went missing on November 15th, 2017, with its last confirmed contact location around 600 kilometres East of Comodoro Rivadavia, Chubut, Argentina. In the days following the initiation of the multi-national search and rescue mission, the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) analysed data recorded by its International Monitoring System (IMS) sensor network for any signals that could support this effort. Two of the IMS hydrophone stations, HA10 in the central Atlantic Ocean and HA04 in the southern Indian Ocean, were found to have recorded an unusual hydroacoustic signal of unknown nature (a “hydroacoustic anomaly”), which originated from the vicinity of the last known location of the ARA San Juan. On December 1st, 2017, confirmation of the detection and localization capability of the IMS network was made possible by a calibration test involving a depth charge deployed by the Argentine Navy. Also this signal was detected by the two IMS hydrophone stations and its origin located to within 39 km of the announced deployment location. After extended search operations, on November 17th, 2018, the ARA San Juan was found on the seabed at approximately 900 metres depth less than 20 km from the location of the hydroacoustic anomaly provided by CTBTO. This paper presents the methodologies applied by CTBTO within months after the loss of the submarine, aimed at detecting, locating and characterizing the November 15th signal of unknown origin and the December 1st calibration explosion.
Freshening rather than warming drives trematode transmission from periwinkles to mussels
Authors: Bommarito Claudia , Pansch Christian , Khosravi Maral , Pranovi Fabio , Wahl Martin , Thieltges David W.
Published: March 2020

In the Western Baltic Sea, climate change is happening at much faster rate than in most other seas and organisms are additionally exposed to a steep and variable salinity gradient. Climate change has previously been shown to affect parasite transmission in other marine ecosystems, yet little is known about potential effects of warming and desalination on parasite–host interactions. In laboratory experiments, we determined the combined effects of projected seawater warming and freshening on the emergence, activity, survival, and infectivity of cercariae (free-swimming infectious stage) of the trematode Himasthla elongata (Mehlis 1831), shed from its first intermediate host, the periwinkle Littorina littorea (Linnaeus 1758), in the Baltic Sea. We also assessed the susceptibility of the second intermediate host, the mussel Mytilus edulis Linnaeus, 1758, to cercarial infections. Generally, salinity was the main driver, particularly of cercarial activity, infectivity, and mussel susceptibility to infection. At the lowest salinity (13), cercariae were 50% less active compared to the highest salinity (19). Infection success and host susceptibility followed a similar pattern, with 47% and 43% less metacercariae (encysted stage) present at salinity 13 than at salinity 19, respectively. In contrast, effects of simulated warming were found only for cercarial survival, with cercarial longevity being higher at 19 than at 23 °C. No significant interactions between temperature and salinity were found. In contrast to the literature, the results suggest that a climate change-driven freshening (partly also warming) may lead to a general decline of marine trematodes, with possible beneficial effects for the involved hosts.
Biotransformation of bisphenol A analogues by the biphenyl-degrading bacterium Cupriavidus basilensis - a structure-biotransformation relationship
Authors: Zühlke Marie-Katherin , Schlüter Rabea , Mikolasch Annett , Henning Ann-Kristin , Giersberg Martin , Lalk Michael , Kunze Gotthard , Schweder Thomas , Urich Tim , Schauer Frieder
Published: March 2020

Comparative analyses determined the relationship between the structure of bisphenol A (BPA) as well as of seven bisphenol analogues (bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bisphenol F (BPF), bisphenol Z (BPZ), bisphenol AP (BPAP), bisphenol PH (BPPH)) and their biotransformability by the biphenyl-degrading bacterium Cupriavidus basilensis SBUG 290. All bisphenols were substrates for bacterial transformation with conversion rates ranging from 6 to 98% within 216 h and 36 different metabolites were characterized. Transformation by biphenyl-grown cells comprised four different pathways: (a) formation of ortho-hydroxylated bisphenols, hydroxylating either one or both phenols of the compounds; (b) ring fission; (c) transamination followed by acetylation or dimerization; and (d) oxidation of ring substituents, such as methyl groups and aromatic ring systems, present on the 3-position. However, the microbial attack of bisphenols by C. basilensis was limited to the phenol rings and its substituents, while substituents on the carbon bridge connecting the rings were not oxidized. All bisphenol analogues with modifications at the carbon bridge could be oxidized up to ring cleavage, while substituents at the 3-position of the phenol ring other than hydroxyl groups did not allow this reaction. Replacing one methyl group at the carbon bridge of BPA by a hydrophobic aromatic or alicyclic ring system inhibited both dimerization and transamination followed by acetylation. While most of the bisphenol analogues exhibited estrogenic activity, four biotransformation products tested were not estrogenically active.
Prevalence of ankylosing spondylitis in a Chinese population: a systematic review and meta-analysis
Authors: Zhao Jinlong , Huang Chuyao , Huang Hetao , Pan Jian-ke , Zeng Ling-feng , Luo Ming-hui , Liang Gui-hong , Yang Wei-yi , Liu Jun
Published: March 2020

Ankylosing spondylitis (AS) is a common inflammatory rheumatic disease that affects the axial skeleton. In this study, we systematically reviewed Chinese AS epidemiological studies from the past 15 years to elucidate its prevalence and provide scientific data for China’s health care system. AS epidemiological research in China was summarized by conducting a literature review. A review and statistical analysis of the literature on the epidemiology of AS in mainland China published from May 2005 to May 2019 were performed via a meta-analysis. We calculated the prevalence of AS and analysed differences by sex, region, and population source using STATA12.0 software. Eleven papers including 122,558 subjects from mainland China were included. Over the past 15 years, the total prevalence of AS in mainland China was 0.29% (95% CI 0.22–0.35%), ranging from 0.42% (95% CI 0.31–0.52%) in males to 0.15% (95% CI 0.13–0.18%) in females; the difference in the prevalence of AS by sex was statistically significant (P < 0.001). The prevalence of AS in both southern and northern China was 0.31% (95% CI 0.21–0.42% and 0.21–0.40%, respectively), with no significant difference noted (P = 0.816 > 0.005). The prevalence of AS in Chinese military populations was 0.27% (95% CI 0.09–0.45%), and in community populations, it was 0.29% (95% CI 0.23–0.35%). There was no statistically significant difference in the prevalence of AS by sampling resource (P = 0.115 > 0.005). The prevalence of AS in China was 0.29% and continues to increase. Sex differences in its prevalence were identified; the prevalence rate was 2.8 times higher in males than in females. Epidemiologists in China should formulate precise scientific investigations to provide additional authoritative epidemiological data for the prevention and treatment of AS.
Detecting scaphoid fractures in wrist injury: a clinical decision rule
Authors: Mallee Wouter H. , Walenkamp M. M. J. , Mulders M. A. M. , Goslings J. C. , Schep N. W. L.
Published: March 2020

Introduction

The aim of this study was to develop and validate an easy to use clinical decision rule, applicable in the ED that limits the number of unnecessary cast immobilizations and diagnostic follow-up in suspected scaphoid injury, without increasing the risk of missing fractures.

Methods

A prospective multicenter study was conducted that consisted of three components: (1) derivation of a clinical prediction model for detecting scaphoid fractures in adult patients following wrist trauma; (2) internal validation of the model; (3) design of a clinical decision rule. The predictors used were: sex, age, swelling of the anatomic snuffbox, tenderness in the anatomic snuffbox, scaphoid tubercle tenderness, painful ulnar deviation and painful axial thumb compression. The outcome measure was the presence of a scaphoid fracture, diagnosed on either initial radiographs or during re-evaluation after 1–2 weeks or on additional imaging (radiographs/MRI/CT). After multivariate logistic regression analysis and bootstrapping, the regression coefficient for each significant predictor was calculated. The effect of the rule was determined by calculating the number of missed scaphoid fractures and reduction of suspected fractures that required a cast.

Results

A consecutive series of 893 patients with acute wrist injury was included. Sixty-eight patients (7.6%) were diagnosed with a scaphoid fracture. The final prediction rule incorporated sex, swelling of the anatomic snuffbox, tenderness in the anatomic snuffbox, painful ulnar deviation and painful axial thumb compression. Internal validation of the prediction rule showed a sensitivity of 97% and a specificity of 20%. Using this rule, a 15% reduction in unnecessary immobilization and imaging could be achieved with a 50% decreased risk of missing a fracture compared with current clinical practice.

Conclusions

This dataset provided a simple clinical decision rule for scaphoid fractures following acute wrist injury that limits unnecessary immobilization and imaging with a decreased risk of missing a fracture compared to current clinical practice.

Clinical prediction rule

1/(1 + EXP (−(0.649662618 × if man) + (0.51353467826 × if swelling anatomic snuffbox) + (−0.79038263985 × if painful palpation anatomic snuffbox) + (0.57681198857 × if painful ulnar deviation) + (0.66499549728 × if painful thumb compression)−1.685).

Trial registration

Trial register NTR 2544, www.trialregister.nl.
Genetic diversity of Fasciola hepatica in Austria
Authors: Husch Christian , Sattmann Helmut , Haefeli Iveta , Prosl Heinrich , Walochnik Julia
Published: March 2020

The worldwide occurring common liver fluke Fasciola hepatica can infect humans and animals and leads to considerable illness and economic loss annually. The aim of this study was to determine the genetic diversity of F. hepatica in Austria. In total, 31 adult flukes isolated from cattle from various regions in Austria were investigated for their cytochrome oxidase subunit 1 (cox1) and nicotinamide dehydrogenase subunit 1 (nad1) gene sequences. It was shown that Austrian isolates of F. hepatica reveal extensive genetic diversity. To the best of our knowledge, these are the first data on the diversity of F. hepatica in Austria.
An anytime algorithm for optimal simultaneous coalition structure generation and assignment
Authors: Präntare Fredrik , Heintz Fredrik
Published: March 2020

An important research problem in artificial intelligence is how to organize multiple agents, and coordinate them, so that they can work together to solve problems. Coordinating agents in a multi-agent system can significantly affect the system’s performance—the agents can, in many instances, be organized so that they can solve tasks more efficiently, and consequently benefit collectively and individually. Central to this endeavor is coalition formation—the process by which heterogeneous agents organize and form disjoint groups (coalitions). Coalition formation often involves finding a coalition structure (an exhaustive set of disjoint coalitions) that maximizes the system’s potential performance (e.g., social welfare) through coalition structure generation. However, coalition structure generation typically has no notion of goals. In cooperative settings, where coordination of multiple coalitions is important, this may generate suboptimal teams for achieving and accomplishing the tasks and goals at hand. With this in mind, we consider simultaneously generating coalitions of agents and assigning the coalitions to independent alternatives (e.g., tasks/goals), and present an anytime algorithm for the simultaneous coalition structure generation and assignment problem. This combinatorial optimization problem has many real-world applications, including forming goal-oriented teams. To evaluate the presented algorithm’s performance, we present five methods for synthetic problem set generation, and benchmark the algorithm against the industry-grade solver CPLEX using randomized data sets of varying distribution and complexity. To test its anytime-performance, we compare the quality of its interim solutions against those generated by a greedy algorithm and pure random search. Finally, we also apply the algorithm to solve the problem of assigning agents to regions in a major commercial strategy game, and show that it can be used in game-playing to coordinate smaller sets of agents in real-time.
How and Why Do Social and Sustainable Initiatives Scale? A Systematic Review of the Literature on Social Entrepreneurship and Grassroots Innovation
Authors: van Lunenburg Marion , Geuijen Karin , Meijer Albert
Published: March 2020

Social and sustainable initiatives generally start small and need to scale to create substantial impact. Our systematic review of 133 articles develops a better understanding of this scaling process. From the literature, we conceptualize impact as the result of two different pathways: ‘scaling out’ (extending geographical space or volume) and ‘scaling up’ (influence on public discourses, political agendas and legislation). The review identified strategy, actor characteristics and institutional environment as key factors for scaling. The literature indicates that for strategy a focus on open structures generates speed and higher impact, but we also found critical views on this. The literature shows that the actor characteristics such as the ambition to scale, equal focus on the economic and the social logic, entrepreneurial skills and leadership are positively related to the level of impact. The institutional environment influences actor characteristics and strategy choices and also has a direct effect on the level of social and sustainable impact.
Assessment of the young adult hip joint using plain radiographs
Authors: Popat R. , Lee S. , George D. A. , Amiras D. , Sarraf K. M.
Published: March 2020

Radiographic examination remains the mainstay of the initial assessment of the young adult hip; however, common parameters are required to assist in the formation of accurate diagnoses and appropriate management plans. This paper aims to summarise the most important aspects of the assessment of plain radiographs performed on the young adult hip joint.
CMR in Pericardial Diseases - an Update
Authors: Vidalakis Eleftherios , Kolentinis Michalis , Gawor Monika , Vasquez Moises , Nagel Eike
Published: March 2020

Purpose of Review

To review the latest developments and the current role of the cardiac magnetic resonance (CMR) in pericardial diseases and their complications.

Recent Findings

Cardiac Magnetic Resonance (CMR) has the ability to incorporate anatomy, physiology, and “virtual histology” strategies to achieve the most accurate diagnosis for even the most demanding, pericardial diseases.

Acute, chronic, recurrent, and constrictive pericarditis as well as pericarditis related complications, pericardial masses and congenital pericardial defects are commonly encountered in clinical practice with relatively significant morbidity and mortality. Owing to the challenging diagnosis, CMR imaging is often employed in confirming the diagnosis and elucidating the underling pathophysiology. In this review we outline the common CMR techniques and their expected diagnostic outcomes.
Long-term strain measurements of traffic and temperature effects on an RC bridge deck slab strengthened with an R-UHPFRC layer
Authors: Sawicki Bartłomiej , Brühwiler Eugen
Published: March 2020

This paper presents the results of 28-month-long monitoring of a slab portion of the Chillon viaducts in Switzerland using strain gauges and thermocouples. This post-tensioned reinforced concrete structure was strengthened with a layer of reinforced ultrahigh-performance fibre-reinforced cementitious composite (UHPFRC). The strain gauges are used to measure stresses in the bottom layer of reinforcement bars in the slab, while thermocouples explain the behaviour of the structure due to temperature variation. The response under both traffic and thermal actions is discussed. It is demonstrated that the stress variation due to the thermal action can be as large as the response due to traffic action even in such a massive structure. Furthermore, recommendations for analysing both traffic and thermal-induced stresses are given. The commonly used simplified method for calculation of fatigue stress is shown to be highly conservative, leading to overestimation of structural action effects by a factor of four.
Challenging the call: Should sports governing bodies be subject to judicial review?
Authors: Cisneros Ben
Published: March 2020

English law is settled in its view that Sports Governing Bodies (“SGBs”) are not amenable to judicial review, following the Court of Appeal decision in R v Disciplinary Committee of the Jockey Club, ex p Aga Khan. However, this article argues that, 27 years on from the leading decision, the issue merits reconsideration owing to flaws in judicial reasoning and, in particular, the subsequent growth of the government’s involvement in sport. Moreover, the availability of judicial review in other jurisdictions and against other self-regulatory organisations suggests that the position of SGBs in English law is anomalous. Since Aga Khan, the courts have developed a private law “supervisory jurisdiction” which somewhat accounts for the absence of judicial review but, building on the work of Michael Beloff QC (among others), this article considers the substantive and procedural limitations of private law in challenging SGBs, finding that judicial review may be a preferable forum for sporting litigants. The paper also provides the opportunity to reflect upon the nature of the public–private divide in English law today.