bluuebunny/crossref_metadata_2025 huggingface dataset:
Creating community: a peer‐led, adaptable postdoc program to build transferable career skills and overcome isolation
Authors: Fork Megan L. , Anderson Elsa C. , Castellanos Adrian A. , Fischhoff Ilya R. , Matsler A. Marissa , Nieman Chelsey L. , Oleksy Isabella A. , Wong Michelle Y.
Published: October 2021

Postdoctoral positions provide critical opportunities for early‐career ecologists to build transferable skills, knowledge, and networks that will prepare them for professional success. However, these positions often come with personal and professional challenges such as stress, isolation, and lack of agency. Here, we describe a peer‐led postdoc program we created to maximize benefits and minimize challenges while preparing ourselves for a wide range of possible future careers using our training and expertise in ecology. We also give recommendations for other postdocs and early‐career scientists in ecology and across science, technology, engineering, and mathematics fields seeking to build a similar program.
Atlantic bluefin tuna spawn early to avoid metabolic meltdown in larvae
Authors: Fiksen Øyvind , Reglero Patricia
Published: October 2021

To predict shifts in phenology and distribution of organisms we need to understand how survival through early life stages depends on environmental conditions. Here, we present a mechanistic model of development, feeding and bioenergetics of early life stages in bluefin tuna and predict the optimal time of the year for them to be born. We find that the availability of prey, particularly nauplii, is sufficient for fast growth in tuna larvae while temperature is moderate during midsummer, but not when temperatures increase later in summer. High temperatures benefit egg and yolk‐sac stages, but the metabolic needs of feeding larvae are hard to sustain during the warmest periods. Heatwaves, such as the one in 2003, increase larval survival potential, but shorten the viable part of the season for the larvae. Atlantic bluefin tuna is a large, highly migratory marine top predator that spawns while temperatures are rising, but before the heat leads to a metabolic meltdown in larvae. This means that food resources modulate how temperature change shifts optimal phenology.
Single‐Site and Cooperative Bond Activation Reactions with Ylide‐Functionalized Tetrylenes: A Computational Study
Authors: Steinert Henning , Löffler Julian , Gessner Viktoria H.
Published: October 2021

Due to their transition metal‐like behavior divalent group 14 compounds bear huge potential for their application in bond activation reactions and catalysis. Here we report on detailed computational studies on the use of ylide‐substituted tetrylenes in the activation of dihydrogen and phenol. A series of acyclic and cyclic ylidyltetrylenes featuring various α‐substituents with different σ‐ and π‐donating capabilities have been investigated which demonstrate that particularly π‐accepting boryl groups lead to beneficial properties and low barriers for single‐site activation reactions, above all in the case of silylenes. In contrast, for the thermodynamically more stable germylenes and stannylenes an alternative mechanism involving the active participation of the ylide ligand in the E−H bond (E=H or PhO) activation process by addition across the element carbon linkage was found to be energetically favored. Furthermore, the boryl substituted tetrylenes allowed for a further activation pathway involving the active participation of the boron element bond. These cooperative mechanisms are especially attractive for the heavier cyclic ylidyltetrylenes in which the loss of the protonated ylide group is prevented due to the cyclic framework. Overall, the present studies suggest that cyclic ylide‐substituted germylenes and stannylenes bear huge potential for cooperative bond activations at mild conditions which should be experimentally addressed in the future.
Solution‐Phase Synthesis of Backbone‐Constrained Cationic Peptoid Hexamers with Antibacterial and Anti‐Biofilm Activities
Authors: Shyam Radhe , Forestier Christiane , Charbonnel Nicolas , Roy Olivier , Taillefumier Claude , Faure Sophie
Published: October 2021

Abstract: Submonomer synthesis in solution and block‐coupling protocols were combined to prepare amphiphilic peptoid hexamers. The amphipathic character arises from the use of hydrophobic aliphatic tert‐butyl side‐chains imposing the cis‐amide backbone conformation and various cationic side‐chains periodically introduced each three residues. Evaluation of the effect on Gram‐positive and Gram‐negative bacterial strains as well as the capacity to impair biofilm formation and the toxicity of one selected compound allowed to highlight the potential of a short constrained peptoid carrying triazolium‐type cationic pendant groups.
The Future of Hybrid and Inorganic Perovskite Materials: Technology Forecasting
Authors: Oniy Aghmiuni Karim , Arabpour Roghabadi Farzaneh , Rezvani Hadi , Alidaei Maryam , Falahi Mohammad , Pashaei Soorbaghi Fatemeh , Ahmadi Vahid
Published: October 2021

Perovskite (PSK) materials have received extensive attention because of their potential use as the active layer of different applications, including capacitors, sensors and detectors, memories, catalysts, fuel cells, and optoelectronic devices (solar cell and light‐emitting diode). Herein, the past, current, and future status of these applications are focused on. The state of each application is investigated using diverse technology indicators. It reveals that among all the applications, the optoelectronic application is the youngest one and has not yet reached the technology growth stage though it possesses most of the recently published patents. Using a technology investment potential evaluation method, the most potent area for investment is explored, indicating that detectors and sensors are the ones with the biggest investment potentials. Remarkably, PSK solar cell dedicates more than 70% of the patents to itself with the highest predicted efficiency of 30% that will be achieved in 2023 according to the curve fitting method and in 2030 according to the S‐curve method. As a perspective, currently, the highest efficiency and stability are achieved for small‐sized PSK solar cells, it is expected that they would be commercialized in electronic equipment applications first, and after overcoming the challenges, large‐scale modules would enter the markets.
Study on bearing capacity characteristics of steel structure support in soft rock roadway
Authors: Wu Ya‐bin , Hu Jian‐hua , Zhang Xu‐yang , Qin Ya‐guang , Zhang Zhi‐bo , Zhao Xing‐chang
Published: October 2021

When the soft rock roadway in underground mine is supported by steel frame, the bearing capacity of steel structure is the key to the success of roadway support. Taking the soft rock roadway support in Mengnuo lead‐zinc mine as an example, this paper studies the displacement and stress change law of U‐shaped steel, I‐shaped steel, rail steel, and surrounding rock, analyzes the bearing capacity characteristics of steel structure support, and conducts field application tests. The results show that: (a) the deformation resistance of U‐shaped steel is the best, the overall deformation of which is 85.0% of that of track steel, followed by that of I‐shaped steel, which is 92% of that of track steel, and the deformation resistance of track steel is the weakest in comparison; (b) the main stress positions of the three kinds of supporting steel structures are the joint of the support shoulder and the waist. When simulating the support of 10 m roadway, the deformation of the middle 4‐6 m roadway is larger than that of the surrounding rock of the head and tail roadway; (c) when the horizontal stress of the deep soft rock roadway is larger, the floor heave of the roadway is larger than that of the shallow roadway only when the side and top support are used; (d) by the analysis of three different forms and stress states of support steel structures, it is found that the shape of support has a great impact on the bearing mechanical characteristics. It is of great value to study the shape of support with more bearing advantages under the same amount of steel.
Study on the influence mechanism of mixture stratification on GCI combustion and the compound injection strategy under high load operation
Authors: Zhang Lipeng , Wang Hu , Zhong Xin , Han Xu , Wang Mengyu , Zheng Zunqing , Yao Mingfa
Published: October 2021

Gasoline compression ignition combustion has demonstrated the potential of getting high fuel efficiency. In this work, two engine models are established in the commercial software Converge 2.3 based on the experimental results of an optical engine and a modified metal engine. The effect mechanism of mixture stratification and the influence of compound control strategy on gasoline compression ignition (GCI) combustion and soot emissions under high load condition are investigated. Results show that synergistic effect of physics and chemistry is the dominant control mechanism of GCI combustion. Stronger mixture stratification can effectively reduce the maximum pressure rise rate (MPRR) and improve the indicated thermal efficiency (ITE) and emissions; applying high EGR will significantly reduce OH radical in the cylinder and subsequently weaken the soot oxidation process, resulting in high soot emission; under the premise of reasonable NOx emission and MPRR, the soot emission can be effectively reduced with a proper advanced main injection timing. The effect of temperature on the soot oxidation process is the primary mechanism for the ultimate soot emission at different main injection timings; properly increasing the interval between the pre‐ and main injection can reduce NOx and soot emissions under the premise of ensuring that the MPRR is within the upper limit. However, the effect is not significant because of the small proportion of preinjection fuel.
Estimating origination times from the early hominin fossil record
Authors: Bobe René , Wood Bernard
Published: October 2021

The age of the earliest recovered fossil evidence of a hominin taxon is all too often equated with that taxon's origination. However, the earliest known fossil record nearly always postdates, sometimes by a substantial period of time, the true origination of a taxon. Here we evaluate the first appearance records of the earliest potential hominins (Sahelanthropus, Ardipithecus, Orrorin), as well as of the genera Australopithecus, Homo, and Paranthropus, to illustrate the considerable uncertainty regarding the actual timing of origin of these taxa. By placing confidence intervals on the first appearance records of early hominin taxa, we can better evaluate patterns of hominin diversity, turnover, and potential correlations with climatic and environmental changes.
Analysis of aroma and polyphenolic compounds in Saperavi red wine vinified in Qvevri
Authors: Ieri Francesca , Campo Margherita , Cassiani Chiara , Urciuoli Silvia , Jurkhadze Ketie , Romani Annalisa
Published: October 2021

The purpose of this study is to analyze and characterize a Georgian red wine from Saperavi grape, obtained in Qvevri (Georgian traditional winemaking method), by using innovative techniques for the determination of the polyphenolic content, aroma, and its correlation to the sensory characteristics. This peculiar red wine, after high‐performance liquid chromatography with diode‐array detection and mass spectrometry (HPLC‐DAD‐MS), headspace solid‐phase microextraction–gas chromatography–mass spectrometry (HS‐SPME‐GC‐MS), and HS‐SPME‐GCxGC‐MS/TOF (two‐dimensional gas chromatography) chemical characterization showed a high polyphenol content (19.6 × 102 mg/L, 38.4% anthocyanins) and a wide range of volatile compounds, among which terpenes were associated with the aroma of flowers, lemongrass, and wood. Analyses were also conducted to determine the total polyphenol content correlated to antioxidant activity with the Folin–Ciocalteu spectrophotometric in vitro method (4.650 g GAE/L). In conclusion, for the first time on Saperavi wine, innovative techniques such as HPLC‐DAD‐MS, GC‐MS, and GCxGC‐MS/TOF were simultaneously applied in association with the traditional analytic techniques to perform a complete chemical characterization. These activities are part of a project about circular viticulture in the Georgian territory that will lead the production of traced quality wines and the valorization of the Georgian wine sector.
Effect of heat‐moisture treatment on the structural and physicochemical characteristics of sand rice (Agriophyllum squarrosum) starch
Authors: Wu Chunsen , Ji Guiying , Gao Fan , Qian Jian‐Ya , Zhang Liang , Li Qian , Zhang Chen
Published: October 2021

A small granule starch from sand rice (Agriophyllum squarrosum) was subjected to heat‐moisture treatment (HMT) at different moisture contents (MCs,15%–30%). With MC≤20%, a higher MC resulted in increases in the starch orders (i.e., short‐range and crystalline structure) with unchanged granule morphology. Nonetheless, a further elevated MC (>20%) gradually destroyed the granule morphology and starch orders. Also, HMT gradually vanished the lamellar structure as MC increased during HMT. These structural evolutions in HMT‐modified starch resulted in greater thermal stability, higher pasting temperature, lower pasting viscosity and weakened digestibility. Particularly, HMT applied directly in sand rice starch at 20% MC obtained the highest amount of SDS and RS (23.6%), which was 2.2‐fold higher than that of native starch. Therefore, the small granule sand rice starch can be modulated by HMT through controlled MC to expand their application range in food production.
3D‐multilayer simulation of microstructure and mechanical properties of porous materials by selective sintering
Authors: Zhou Xiandong , Yang Yangyiwei , Bharech Somnath , Lin Binbin , Schröder Jörg , Xu Bai‐Xiang
Published: October 2021

This work presents multilayer phase‐field simulation of selective sintering process and the calculation of effective mechanical properties and residual stress of the microstructure using the finite element method. The dependence of the effective properties and residual stress on the process parameters, such as beam power and scan speed, are analyzed. Significant partial melting of powders is observed for large beam power and low scan speed, which results in low porosity of the microstructure. Nonlinear relationship between the effective mechanical properties and process parameters is observed. The increasing rate of effective mechanical properties decreases with increasing beam power, while increases with decreasing scan speed. The dependence of effective Young's modulus and Poisson's ratio on porosity are well established using power law models. Stress concentrations are found at the necking region of powders and the intensity increases with the level of partial melting, which results in increasing residual stress in the microstructure. The numerical results reveal quantitatively the process‐microstructure‐property relation, which implies the feasibility of the subsequent data‐driven approach.
The characteristics and controlling factors of glutenite reservoirs in the Permian Upper Urho Formation, southern Zhongguai Rise, Junggar Basin, NW China
Authors: Chen Hongfei , Lv Qijun , Gao Jun , Yu Jingfeng , Pang Yanqing , Li Bin , Zheng Aiping , Ju Shichang , He Naixiang , Luo Shuai , Wang Xiaoqiang
Published: October 2021

The southern Zhongguai Rise, the petroliferous zones in northwestern Junggar Basin, is among the most significant sedimentary basins in China because of its abundant petroleum reserves. The reservoir characteristics and their responses to controlling factors have been complex in the Permian Upper Urho Formation. A systematic investigation has been conducted based on integrated analysis of seismic volumes, wireline logs, mud logs, cores, thin sections, SEM, grain size data, porosity‐permeability data, and mercury injection test results. The results indicate that the Upper Urho Formation consists of five types of lithology (glutenite, coarse‐grained sandstone, medium‐grained sandstone, fine‐grained sandstone, and siltstone). Furthermore, the detrital composition in Upper Urho Formation is predominantly composed of debris (mainly volcanic rocks), with relatively less contents of quartz and feldspar. The cement is dominated by calcite, laumontite, and siliceous. In addition, the reservoir space in Upper Urho Formation includes intergranular pore, intragranular pore, dissolution pore, and microfracture. The intergranular pore and dissolution pore comprise the main reservoirs. The reservoirs in Upper Urho Formation are characterized by micro‐fine pore‐throat and low‐porosity permeability. Diagenesis along with sedimentary facies exerts the controls on the reservoir heterogeneity and physical properties.
Early Cretaceous uplift of the Jiaobei Terrane: Evidence from the detrital zircon and sediment compositions of sandstones in the Jiaodong Peninsula, China
Authors: Ren Xiang , Han Zuozhen , Dong Yunpeng , Han Chao , Song Zhigang , Zhong Wenjian
Published: October 2021

In this study, we conducted sandstone petrography analyses and determined detrital zircon U–Pb ages and Hf isotopes for sandstones collected at different stratigraphic levels of the lowest strata of the Laiyang Group. All results nearly point to an evolutionary trend for the source regions of the strata. The detrital zircon U–Pb results reveal multiple age groups at 140–123 Ma, 810–700 Ma, and 2,500–1,750 Ma, but variable age proportions for two sandstones (19LY‐01Z and ‐05Z) collected at lowermost and middle levels of strata, respectively, but only one unimodal age mode at ca. 1,850 Ma for the uppermost sandstone 19LY‐09Z. Provenance analysis illustrates that the lower strata likely include two source regions, including the Jiaobei Terrane and the Sulu orogen, whereas the upper strata appeared to have one dominant source region (i.e., Jiaobei Terrane). Framework modes of sandstones display that lower samples contain more metamorphic lithic fragments, which corresponds to the recycled orogenic field in the Q‐F‐L diagram, while middle‐upper samples are enriched in feldspars but deficient in lithics and plot in the basement uplift field of the Q‐F‐L diagram. This compositional variation reflects an evolution of the source regions from the Sulu Orogen to the Jiaobei Terrane, completely consistent with the observation of an increase in the amount of detrital zircons sourced from the Jiaobei Terrane, but decreasing detrital zircons from the Sulu Orogen in an upward order. This shift in the provenance of sediments reflects two tectonic events including exhumation of the Sulu Orogen to the surface before sedimentation of the Laiyang Group, and a rapid uplift of the Jiaobei Terrane after ca. 125 Ma following removal of lithospheric mantle.
What motivates individual public service motivation and cooperation at the initial stage of the COVID‐19 outbreak: A cross‐sectional survey
Authors: Zhang Shu'e , Wang Xiaohe , Shi Yu , Liu Bei , Huang XianHong , Wang Hongni , Zhao Xin , Cao Depin , Sun Tao
Published: October 2021

Objectives

This study assesses the status of public service motivation and explains it's the positive association with public cooperation during the initial stage of the COVID‐19 crisis. Moreover, potential causes of Chinese citizens' public service motivation have been explored.

Methods

A cross‐sectional survey of 30 provinces in China was conducted using an online questionnaire. The study was conducted in February 2020 during the initial stage of the COVID‐19 pandemic. Socio‐demographic factors, public service motivation, public satisfaction, public confidence, and public cooperation were assessed using questionnaires. Hierarchical multiple regression was used to identify clusters of interrelationships among public service motivation, public satisfaction, public confidence, and public cooperation among Chinese citizens.

Results

We found that participants' public satisfaction with COVID‐19‐related public services had a positive association with public confidence (B = 0.456, p < 0.001) and public service motivation (B = 0.177,p < 0.001). Moreover, public confidence regarding anti‐COVID‐19 measures had a positive influence on public service motivation (B = 0.308, p < 0.001) while mediating the relationship between public satisfaction and public service motivation. Public service motivation were positively associated with public cooperation with anti‐COVID‐19 measures during the initial stage of the COVID‐19 pandemic.

Conclusion

A considerably high level of public service motivation among Chinese citizens appeared during the initial stage of the COVID‐19 pandemic, resulting in an increase in public cooperation. Moreover, the findings prove that a high degree of satisfaction with the government's initiatives regarding anti‐COVID‐19 measures encouraged greater personal public service motivation in respondents by increasing confidence in governmental responses and performance.
Charge Transfer in Ternary Solar Cells Employing Two Fullerene Derivatives: Where do Electrons Go?
Authors: Sperlich Andreas , Auth Michael , Dyakonov Vladimir
Published: October 2021

Earlier reports demonstrated that ternary organic solar cells (OSC) made of donor polymers (D) blended with different mixtures of fullerene acceptors (A : A) performed very similarly. This finding is surprising, as the corresponding fullerene LUMO levels are slightly different, which might result in decisive differences in the charge transfer step. We investigate ternary OSC (D : A : A) made of the donor polymer P3HT with stoichiometric mixtures of different fullerene derivatives, PC60BM : PC70BM and PC70BM : IC60BA, respectively. Using quantitative electron paramagnetic resonance (EPR) we can distinguish between positive and negative polarons, localized on the specific molecules. We found that after the initial charge transfer step, the electrons are re‐distributed over two nearby acceptors in agreement with their stoichiometry and their relative LUMO energy difference. Remarkably, the measured ΔLUMO differences in fullerene mixtures are reduced by an order of magnitude compared to that of the pristine materials, i. e., below 1 meV for PC60BM : PC70BM and (20±5) meV for PC70BM : IC60BA. Furthermore, we found that this reduced ΔLUMO explains the shift in open circuit voltage for D : A : A organic solar cells. We attribute these findings to hybridization, leading to an effective fullerene LUMO. Consequently, multi‐acceptor blends are indeed a viable option for photodetectors and solar cells, as they combine the best electron acceptor and light absorbing properties.
Progress in the pathological arena of gynecological cancers
Authors: McCluggage W. Glenn
Published: October 2021

This review covers the significant new developments in the pathological classification of gynecological tumors. Many of these were included in the updated World Health Organization Classification of Female Genital Tract Tumours, published in 2020. Topics include the compelling evidence that a large majority of extrauterine high‐grade serous carcinomas arise from the fallopian tube; the Cancer Genome Atlas (TCGA) Classification of endometrial carcinomas; the discovery that most so‐called synchronous endometrial and ovarian endometrioid carcinomas represent metastasis from the endometrium to the ovary; and the division of cervical, vaginal, and vulval carcinomas into clinically meaningful HPV‐associated and HPV‐independent types. Newly described tumor types are covered, including endometrial and ovarian mesonephric‐like adenocarcinoma, uterine sarcoma types associated with specific molecular abnormalities, and gastric (gastrointestinal)‐type adenocarcinomas of the endometrium and vagina. Important molecular events in ovarian sex cord–stromal tumors are also discussed.
Increased spontaneous preterm births during the second wave of the coronavirus disease 2019 pandemic in India
Authors: Mahajan Niraj N. , Pednekar Rahi , Gaikwad Chaitanya , More Prajakta , Pophalkar Madhura , Kesarwani Shweta , Jnanananda Bhargavi , Mahale Smita D , Gajbhiye Rahul K
Published: October 2021

Objective

To compare spontaneous preterm birth (SPTB) and iatrogenic preterm birth (IPTB) rates during both waves of the coronavirus disease 2019 (COVID‐19) pandemic.

Methods

Retrospective analysis of the PregCovid registry of pregnant women with COVID‐19 was performed at a dedicated COVID‐19 hospital in Mumbai, India. The data of 1630 women were analyzed for this study between April 4, 2020 and July 4, 2021. Prepandemic data were analyzed and compared with pandemic data. Main outcome measure was spontaneous preterm birth rate.

Results

Preterm deliveries were higher during the second wave (46/329; 14%) compared with the first wave (82/807; 10.2%) of the COVID‐19 pandemic (P = 0.065). Higher SPTBs were reported during the second wave than the first wave (12.5% versus 8.3%) (P = 0.03) as well as the prepandemic period (12.5% versus 10.5%) (P = 0.286). IPTBs were significantly lower in the pandemic period than in the prepandemic period (1.8 versus 3.3) (P = 0.012).

Conclusion

In Mumbai, India, we found an unusual change in SPTBs during the 6 months of the second wave of COVID‐19 compared with the previous 10 months of the first wave of pandemic and 1 year of prepandemic.
Placenta accreta risk—antepartum score in predicting clinical outcomes of placenta accreta spectrum: A multicenter validation study
Authors: Shazly Sherif A. , Anan Mohamed A. , Makukhina Tatiana B. , Melekoglu Rauf , Ahmed Farhat ul A. , Pinto Pedro V. , Takahashi Hironori , Ahmed Nermeen B. , Sayed Esraa G. , Elassall Gena M. , Said Aliaa E. , Fahmy Mohamed S. , Dawyee Diaa M. , Penzhoyan Gregory A. , Amirkhanyan Arpine M. , Yılmaz Ercan , Celik Nesibe Z. , Aziz Hijab , Akhter Tayyaba , Ambreen Afshan , Abdelbadie Amr S.
Published: October 2021

Objective

To validate the use of placenta accreta risk—antepartum (PAR‐A) score as a predictive tool of clinical outcomes of placenta accreta spectrum (PAS).

Methods

This is a prospective study, conducted in six PAS specialized centers in six different countries. The study was conducted between October 1, 2020 and March 31, 2021. Women who were provisionally diagnosed with PAS during pregnancy were considered eligible. A machine‐learning‐based PAR‐A score was calculated. Diagnostic performance of the PAR‐A score was evaluated using a receiver operating characteristic curve, for perioperative massive blood loss and admission to intensive care unit (ClinicalTrials.gov identifier NCT04525001).

Results

Of 97 eligible women, 86 were included. PAS‐associated massive blood loss occurred in 10 patients (11.63%). Median PAR‐A scores of massive blood loss in the current cohort were 8.9 (interquartile range 6.9–14.1). In predicting massive blood loss, the area under the curve of PAR‐A scores was 0.85 (95% confidence interval [CI] 0.74–0.95), which was not significantly different from the original cohort (P = 0.2). PAR‐A score prediction of intensive care unit admission was slightly higher compared with the original cohort (0.88, 95% CI 0.81–0.95; P = 0.06).

Conclusion

PAR‐A score is a novel scoring system of PAS outcomes, which showed external validity based on current data.
First successful case of platinum‐based chemotherapy for neuroendocrine prostate cancer withBRCA2andPTENalterations
Authors: Omura Minami , Kosaka Takeo , Aimono Eriko , Nakamura Kohei , Hongo Hiroshi , Mikami Shuji , Nishihara Hiroshi , Oya Mototsugu
Published: October 2021

Introduction

Deoxyribonucleic acid repair gene mutations are now being studied in a variety of solid tumors, with the hope of predicting prognosis, pathogenesis, and treatment outcomes.

Case presentation

We report the case of a Japanese patient with advanced castration‐resistant prostate cancer who exhibited a prominent response to platinum therapy and had coexistingBRCA2andPTENmutations according to retrospective multigene panel analysis.

Conclusion

Through a review of clinical outcomes and genetic/pathologic profiling, the presented case provides insights into future management strategies based on the tumor genetic status.
Polarization‐sensitive and wide‐spectrum photovoltaic detector based on quasi‐1D ZrGeTe4 nanoribbon
Authors: Bai Ruixue , Xiong Tao , Zhou Jinshu , Liu Yue‐Yang , Shen Wanfu , Hu Chunguang , Yan Faguang , Wang Kaiyou , Wei Dahai , Li Jingbo , Yang Juehan , Wei Zhongming
Published: October 2021

Low‐dimensional semiconductors with in‐plane anisotropy and narrow bandgap have been extensively applied to polarized detection in the near‐infrared (NIR) region. However, the narrow bandgap can cause noise owing to the high dark current in photodetectors. This article reports quasi‐1D ZrGeTe4 nanoribbon‐based photodetectors with low dark current and broadband polarization detection. The photodetector was fabricated by evaporating 50‐nm‐thick Au electrodes on a ZrGeTe4 nanoribbon. Benefiting from the photovoltaic characteristics in the ZrGeTe4 nanoribbon and Au electrodes, these photodetectors can operate without bias voltage, with decreased dark current, and improved device performance. Furthermore, the quasi‐1D ZrGeTe4 nanoribbon‐based photodetectors demonstrate a polarization sensitivity in a broadband from visible (VIS) to the NIR region, such as a high photoresponsivity of 625.65 mA W−1, large external quantum efficiency of 145.9% at 532 nm, and photocurrent anisotropy ratio of 2.04 at 1064 nm. They exhibit a novel perpendicular optical reversal of 90° in polarization‐sensitive photodetection, angle‐resolved absorption spectra, and azimuth‐dependent reflectance difference microscopy (ADRDM) from VIS to the NIR region, as opposed to other nanoribbon‐based polarization‐sensitive photodetectors. This work paves the way for utilizing photovoltaic photodetectors based on low‐dimensional materials for broad‐spectrum polarized photodetection.
Celecoxib decreases mitochondrial complex IV activity and induces oxidative stress in isolated rat heart mitochondria: An analysis for its cardiotoxic adverse effect
Authors: Atashbar Saman , Jamali Zhaleh , Khezri Saleh , Salimi Ahmad
Published: October 2021

In spite of the cardiotoxic effect of selective cyclooxygenase‐2 inhibitors, they are most widely used as anti‐inflammatory and analgesic drugs. Today, valdecoxib and rofecoxib have been withdrawn in the market but celecoxib remains. In this study, we focused on an analysis of celecoxib toxic effects on isolated mitochondria. Isolated rat heart mitochondria were obtained using differential centrifugation. Using flow cytometry and biochemical assays, we searched succinate dehydrogenases, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) formation, mitochondrial swelling, ATP/ADP ratio, lipid peroxidation, and mitochondrial complexes activity in rat heart isolated mitochondria. Herein, our results indicated a significant decrease in the activity of complex IV after exposure with celecoxib (16 µg/ml). This decrease in the activity of complex IV is paralleled by the MMP collapse, ROS formation, mitochondrial swelling, depletion of ATP, and lipid peroxidation. For the first time, this introductory study has shown a significant decrease in the activity of complex IV and mitochondrial dysfunction after exposure with celecoxib in rat heart isolated mitochondria.
Refractory vaccine‐induced immune thrombotic thrombocytopenia (VITT) managed with delayed therapeutic plasma exchange (TPE)
Authors: Major Ajay , Carll Timothy , Chan Clarence W. , Christenson Chancey , Aldarweesh Fatima , Wool Geoffrey D. , Cohen Kenneth S.
Published: October 2021

Vaccine‐induced immune thrombotic thrombocytopenia (VITT) is a newly described hematologic disorder, which presents as acute thrombocytopenia and thrombosis after administration of the ChAdOx1 nCov‐19 (AstraZeneca) and Ad26.COV2.S (Johnson & Johnson) adenovirus‐based vaccines against COVID‐19. Due to positive assays for antibodies against platelet factor 4 (PF4), VITT is managed similarly to autoimmune heparin‐induced thrombocytopenia (HIT) with intravenous immunoglobulin (IVIG) and non‐heparin anticoagulation. We describe a case of VITT in a 50‐year‐old man with antecedent alcoholic cirrhosis who presented with platelets of 7 × 103/μL and portal vein thrombosis 21 days following administration of the Ad26.COV2.S COVID‐19 vaccine. The patient developed progressive thrombosis and persistent severe thrombocytopenia despite IVIG, rituximab and high‐dose steroids and had persistent anti‐PF4 antibodies over 30 days after his initial presentation. As such, delayed therapeutic plasma exchange (TPE) was pursued on day 32 of admission as salvage therapy, with a sustained improvement in his platelet count. Our case serves as proof‐of‐concept of the efficacy of TPE in VITT.
Harnessing autophagy to fight SARS‐CoV‐2: An update in view of recent drug development efforts
Authors: Rein Theo
Published: October 2021

Drug repurposing is an attractive option for identifying new treatment strategies, in particular in extraordinary situations of urgent need such as the current coronavirus disease 2019 (Covid‐19) pandemic. Recently, the World Health Organization announced testing of three drugs as potential Covid‐19 therapeutics that are known for their dampening effect on the immune system. Thus, the underlying concept of selecting these drugs is to temper the potentially life‐threatening overshooting of the immune system reacting to severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) infection. This viewpoint discusses the possibility that the impact of these and other drugs on autophagy contributes to their therapeutic effect by hampering the SARS‐CoV‐2 life cycle.
The effects of blood in self‐injurious cutting: Positive and negative affect regulation
Authors: Stacy Stephanie E. , Pepper Carolyn M. , Clapp Joshua D. , Reyna Alejandra H.
Published: October 2021

Objective

Seeing one's own blood may be a factor in affect regulation in nonsuicidal self‐injury (NSSI). This study examined changes in a negative (NA) and positive affect (PA) in response to a finger prick eliciting a small drop of participants' blood.

Methods

Two groups (NSSI; N = 56 and Control; N = 70) of undergraduate students were randomly assigned to receive a finger prick and look at blood, receive a finger prick and not look at blood, or receive a sham finger prick. Following a mood induction, participants completed the PANAS three times: Time 1 (pre mood‐induction, baseline), Time 2 (post‐mood induction), and Time 3 (post‐finger prick condition), and a Pain Severity Scale.

Results

A significant three‐way interaction revealed that the NSSI: Blood Group had an increased positive effect between Time 2 and Time 3.

Conclusion

Blood serves an important function in NSSI and requires additional research to fully understand the relationship.
Suicide attempts among adults denying active suicidal ideation: An examination of the relationship between suicidal thought content and suicidal behavior
Authors: Wastler Heather M. , Bryan AnnaBelle O. , Bryan Craig J.
Published: October 2021

Objectives

The purpose of the current study was to examine the possibility that there are multiple pathways to suicidal behavior by conducting a fine‐grained investigation of the relationship between suicidal thought content and suicidal behavior.

Methods

Six thousand two hundred US adults completed self‐report measures of suicidal thoughts and behaviors. Descriptive statistics and logistic regression were used to examine the relationship between suicidal thoughts and behaviors.

Results

About 36.0% of participants with a lifetime suicide attempt denied ever experiencing any active suicidal thoughts and 11.0% denied ever experiencing any suicidal thoughts; 53.8% of recent attempters denied recent active suicidal thoughts and 22.6% denied any recent suicidal thoughts. Additionally, the sole presence of passive suicidal ideation was associated with increased odds of lifetime and past‐month suicide attempts.

Conclusions

These findings suggest that there are likely multiple pathways to suicide, some of which do not involve progressively worsening suicidal thoughts.
Multidirectional focus measure for accurate three‐dimensional shape recovery of microscopic objects
Authors: Shim Seong‐O
Published: October 2021

Shape from focus (SFF) is a technique to recover the shape of an object from multiple images taken at various focus settings. Most of conventional SFF techniques compute focus value of a pixel by applying one of focus measure operators on neighboring pixels on the same image frame. However, in the optics with limited depth of field, neighboring pixels of an image have different degree of focus for curved objects, thus the computed focus value does not reflect the accurate focus level of the pixel. Ideally, an accurate focus value of a pixel needs to be measured from the neighboring pixels lying on tangential plane of the pixel in image space. In this article, a tangential plane on each pixel location (i, j) in image sensor is searched by selecting one of five candidate planes based on the assumption that the maximum variance of focus values along the optical axis is achieved from the neighborhood lying on tangential plane of the pixel (i, j). Then, a focus measure operator is applied on neighboring pixels lying on the searched plane. The experimental results on both the synthetic and real microscopic objects show the proposed method produces more accurate three‐dimensional shape in comparison to conventional SFF method that applies focus measures on original image planes.
Cell trafficking and regulation of osteoblastogenesis by extracellular vesicle associated bone morphogenetic protein 2
Authors: Yerneni Saigopalakrishna S. , Adamik Juraj , Weiss Lee E. , Campbell Phil G.
Published: October 2021

Extracellular vesicles (EVs) are characterized by complex cargo composition and carry a wide array of signalling cargo, including growth factors (GFs). Beyond surface‐associated GFs, it is unclear if EV intralumenal growth factors are biologically active. Here, bone morphogenetic protein‐2 (BMP2), loaded directly into the lumen of EVs designated engineered BMP2‐EVs (eBMP2‐EVs), was comprehensively characterized including its regulation of osteoblastogenesis. eBMP2‐EVs and non‐EV ‘free’ BMP2 were observed to similarly regulate osteoblastogenesis. Furthermore, cell trafficking experiments suggest rapid BMP2 recycling and its extracellular release as ‘free’ BMP2 and natural occurring BMP2‐EVs (nBMP2‐EVs), with both being osteogenic. Interestingly, BMP2 occurs on the EV surface of nBMP2‐EVs and is susceptible to proteolysis, inhibition by noggin and complete dissociation from nBMP2‐EVs over 3 days. Whereas, within the eBMP2‐EVs, BMP2 is protected from proteolysis, inhibition by noggin and is retained in EV lumen at 100% for the first 24 h and ∼80% after 10 days. Similar to ‘free’ BMP2, bioprinted eBMP2‐EV microenvironments induced osteogenesis in vitro and in vivo in spatial registration to the printed patterns. Taken together, BMP2 signalling involves dynamic BMP2 cell trafficking in and out of the cell involving EVs, with distinct differences between these nBMP2‐EVs and eBMP2‐EVs attributable to the BMP2 cargo location with EVs. Lastly, eBMP2‐EVs appear to deliver BMP2 directly into the cytoplasm, initiating BMP2 signalling within the cell, bypassing its cell surface receptors.
Evaluation of Hepatic Iron Overload Using a Contemporary 0.55 T MRI System
Authors: Campbell‐Washburn Adrienne E. , Mancini Christine , Conrey Anna , Edwards Lanelle , Shanbhag Sujata , Wood John , Xue Hui , Kellman Peter , Bandettini W. Patricia , Thein Swee Lay
Published: October 2021

Background

MRI T2* and R2* mapping have gained clinical acceptance for noninvasive assessment of iron overload. Lower field MRI may offer increased measurement dynamic range in patients with high iron concentration and may potentially increase MRI accessibility, but it is compromised by lower signal‐to‐noise ratio that reduces measurement precision.

Purpose

To characterize a high‐performance 0.55 T MRI system for evaluating patients with liver iron overload.

Study Type

Prospective.

Population

Forty patients with known or suspected iron overload (sickle cell anemia [n = 5], ß‐thalassemia [n = 3], and hereditary spherocytosis [n = 2]) and a liver iron phantom.

Field strength/sequence

A breath‐held multiecho gradient echo sequence at 0.55 T and 1.5 T.

Assessment

Patients were imaged with T2*/R2* mapping 0.55 T and 1.5 T within 24 hours, and 16 patients returned for follow‐up exams within 6–16 months, resulting in 56 paired studies. Liver T2* and R2* measurements and standard deviations were compared between 0.55 T and 1.5 T and used to validate a predictive model between field strengths. The model was then used to classify iron overload at 0.55 T.

Statistical Tests

Linear regression and Bland–Altman analysis were used for comparisons, and measurement precision was assessed using the coefficient of variation. A P‐value < 0.05 was considered statistically significant.

Results

R2* was significantly lower at 0.55 T in our cohort (488 ± 449 s−1 at 1.5 T vs. 178 ± 155 s−1 at 0.55 T, n = 56 studies) and in the patients with severe iron overload (937 ± 369 s−1 at 1.5 T vs. 339 ± 127 s−1 at 0.55 T, n = 23 studies). The coefficient of variation indicated reduced precision at 0.55 T (3.5 ± 2.2% at 1.5 T vs 6.9 ± 3.9% at 0.55 T). The predictive model accurately predicted 1.5 T R2* from 0.55 T R2* (Bland Altman bias = −6.6 ± 20.5%). Using this model, iron overload at 0.55 T was classified as: severe R2* > 185 s−1, moderate 81 s−1 < R2* < 185 s−1, and mild 45 s−1 < R2* < 91 s−1.

Data Conclusion

We demonstrated that 0.55 T provides T2* and R2* maps that can be used for the assessment of liver iron overload in patients.

Evidence Level

2

Technical Efficacy

Stage 2
Transfer Learning Strategy Based on Unsupervised Learning and Ensemble Learning for Breast Cancer Molecular Subtype Prediction Using Dynamic Contrast‐Enhanced MRI
Authors: Sun Rong , Hou Xuewen , Li Xiujuan , Xie Yuanzhong , Nie Shengdong
Published: October 2021

Background

Imaging‐driven deep learning strategies focus on training from scratch and transfer learning. However, the performance of training from scratch is often impeded by the lack of large‐scale labeled training data. Additionally, owing to the differences between source and target domains, analyzing medical image tasks satisfactorily via transfer learning based on ImageNet is difficult.

Purpose

To investigate two transfer learning algorithms for breast cancer molecular subtype prediction (luminal and non‐luminal) based on unsupervised pre‐training and ensemble learning: M_EL and B_EL, using malignant and benign datasets as the source domain, respectively.

Study Type

Retrospective.

Population

Eight hundred and thirty‐three female patients with histologically confirmed breast lesions (567 benign and 266 malignant cases) were selected. In the 5‐fold cross‐validation, the malignant cohort was randomly divided into 5 subsets to form a training set (80%) and a validation set (20%).

Field Strength/Sequence

3.0 T, dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) using T1‐weighted high‐resolution isotropic volume examination.

Assessment

First, three datasets acquired at different times post‐contrast were preprocessed as unlabeled source domains. Second, three baseline networks corresponding to the different MRI post‐contrast phases were built, optimized by a combination of mutual information maximization between high‐ and low‐level representations and prior distribution constraints. Next, the pre‐trained networks were fine‐tuned on the labeled target domain. Finally, prediction results were integrated using weighted voting‐based ensemble learning.

Statistical Tests

Mean accuracy, precision, specificity, and area under receiver operating characteristic curve (AUC) were obtained with 5‐fold cross‐validation. P < 0.05 was considered to be statistically significant.

Results

Compared with a convolutional long short‐term memory network, pre‐trained VGG‐16, VGG‐19, and DenseNet‐121 from ImageNet, M_EL and B_EL exhibited significantly more optimized prediction performance (specificity: 90.5% and 89.9%; accuracy: 82.6% and 81.1%; precision: 91.2% and 90.9%; AUC: 0.836 and 0.823, respectively).

Data Conclusion

Transfer learning based on unsupervised pre‐training may facilitate automatic prediction of breast cancer molecular subtypes.

Level of Evidence

3

Technical Efficacy

Stage 2
Q‐Dixon and GRAPPATINI T2 Mapping Parameters: A Whole Spinal Assessment of the Relationship Between Osteoporosis and Intervertebral Disc Degeneration
Authors: Li Xiangwen , Xie Yuxue , Lu Rong , Zhang Yuyang , Li Qing , Kober Tobias , Hilbert Tom , Tao Hongyue , Chen Shuang
Published: October 2021

Background

The relationship between osteoporosis and intervertebral disc (IVD) degeneration remains controversial. Novel quantitative Dixon (Q‐Dixon) and GRAPPATINI T2 mapping techniques have shown potential for evaluating the biochemical components of the spine.

Purpose

To investigate the correlation of osteoporosis with IVD degeneration in postmenopausal women.

Study Type

Prospective.

Subjects

A total of 105 postmenopausal females (mean age, 65 years; mean body mass index, 26 kg/m2).

Field Strength/Sequence

3 T; sagittal; 6‐echo Q‐Dixon, multiecho spin‐echo GRAPPATINI T2 mapping, turbo spin echo (TSE) T1‐weighted and TSE T2‐weighted sequences.

Assessment

The subjects were divided into normal (N = 47), osteopenia (N = 28), and osteoporosis (N = 30) groups according to quantitative computed tomography examination. The Pfirrmann grade of each IVD was obtained. Region of interest analysis was performed separately by two radiologists (X.L., with 10 years of experience, and S.C., with 20 years of experience) on a fat fraction map and T2 map to calculate the bone marrow fat fraction (BMFF) from the L1 to L5 vertebrae and the T2 values of each adjacent IVD separately.

Statistical Tests

One‐way analysis of variance, post‐hoc comparisons, and Kruskal–Wallis H tests were performed to evaluate the differences in the magnetic resonance imaging parameters between the groups. The relationships between BMFF and the IVD features were analyzed using the Spearman correlation analysis and linear regression models.

Results

There were significant differences in BMFF among the three groups. The osteoporosis group had higher BMFF values (64.5 ± 5.9%). No significant correlation was found between BMFF and Pfirrmann grade (r = 0.251, P = 0.06). BMFF was significantly negatively correlated with the T2 of the adjacent IVD from L1 to L3 (r = −0.731; r = −0.637; r = −0.547), while significant weak correlations were found at the L4 to L5 levels (r = −0.337; r = −0.278).

Data Conclusion

This study demonstrated that osteoporosis is associated with IVD degeneration.

Level of Evidence

2

Technical Efficacy

Stage 4
Better detection of Torque teno virus in children with leukemia by metagenomic sequencing than by quantitative PCR
Authors: Leijonhufvud Gustaf , Bajalan Amanj , Teixeira Soratto Tatiany Aparecida , Gustafsson Britt , Bogdanovic Gordana , Bjerkner Annelie , Allander Tobias , Ljungman Gustaf , Andersson Björn
Published: October 2021

Torque teno virus (TTV) is a group of chronically persisting viruses with a short circular DNA genome. TTV demonstrates a wide sequence diversity and a large majority of humans are chronically infected by one or more types of TTV. As TTV is ubiquitous, and viral replication correlates with immune status, TTV has been studied as a marker to assess global functional immune competence in transplant recipients. Most studies of the prevalence, amounts, and variation in TTV have been performed using PCR assays. We here present a comparison of the most frequently used quantitative PCR (qPCR) assay for TTV with shotgun metagenomic sequencing for detection and characterization of TTV in a cohort of pediatric cancer patients. The results show that TTV is more common than the qPCR assays indicate, and analysis of the TTV genome sequences indicate that a qPCR with primers and probe designed on a conserved region of the TTV genome may fail to detect some of the TTV strains found in this study.