bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent advances in applications of surfactant‐based voltammetric sensors
Authors: Housaindokht Mohammad Reza , Janati‐Fard Fatemeh , Ashraf Narges
Published: August 2021

Voltammetric sensors are simple, powerful, and cheap equipment with easy principles, which have been widely used in electrochemical studies to investigate the properties of the electroactive species. Surfactants are frequently used in the construction of voltammetric sensors to enhance the sensitivity and selectivity of the sensor, which significantly impacted the electrode function in terms of dissolving organic compounds, creating a specific orientation of molecules on the surface of the electrodes, and enhancing electron transfer reactions. This review focuses on the recent contributions of surfactants in the development of efficient voltammetric sensors. In addition, other ingredients commonly employed alongside surfactants, such as nanomaterials, conducting polymers, and composite materials, have been discussed. The comprehension of these aspects can guide the expansion and the use of surfactants in the electrochemical sensing scope.
Effects of Winter Ticks and Internal Parasites on Moose Survival in Vermont, USA
Authors: Debow Jacob , Blouin Joshua , Rosenblatt Elias , Alexander Cedric , Gieder Katherina , Cottrell Walter , Murdoch James , Donovan Therese
Published: August 2021

Moose (Alces alces) have experienced considerable declines along the periphery of their range in the northeastern United States. In Vermont, the population declined 45% from 2010 to 2017 despite minimal hunter harvest and adequate habitat. Similarly, nearby populations recently experienced epizootics characterized by >50% mortality. Declines have largely been associated with the effects of winter ticks (Dermacentor albipictus), but uncertainty exists about the effects of environmental and other parasite‐related conditions on moose survival. We examined patterns of moose survival among a radio‐collared population (n = 127) in Vermont from 2017 to 2019. Our objectives were to estimate causes of mortality and model survival probability as a function of individual and landscape variables for calves (<1 yr) and adults (≥1 yr). Observed adult survival was 90% in 2017, 84% in 2018, and 86% in 2019, and winter calf survival was 60% in 2017, 50% in 2018, and 37% in 2019. Winter tick infestation was the primary cause of mortality (91% of calves, 25% of adults), and 32% of all mortalities had evidence of meningeal worm (Parelaphostrongylus tenuis). Other sources of mortality such as vehicles, harvest, predation, deep snow, and other parasitic infections were negligible. The best supported calf model included sex differences and negative effects of tick engorgement (%/week) and parasite level (roundworm and lungworm). The best supported adult model included the effect of cumulative tick engorgement (cumulative %/week), which negatively affected survival. Our results indicate that winter tick engorgement strongly affects survival, and is probably compounded by the presence of meningeal worm and other parasites. Reduced tick effects may be achieved by decreasing moose density through harvest and managing late winter habitat to minimize tick density. Management of white‐tailed deer (Odocoileus virginianus) density may also affect the transmission of meningeal worm. © 2021 The Authors.The Journal of Wildlife Managementpublished by Wiley Periodicals LLC on behalf of The Wildlife Society.
Understanding the effects of climate change via disturbance on pristine arctic lakes—multitrophic level response and recovery to a 12‐yr, low‐level fertilization experiment
Authors: Budy Phaedra , Pennock Casey A. , Giblin Anne E. , Luecke Chris , White Daniel L. , Kling George W.
Published: August 2021

Effects of climate change‐driven disturbance on lake ecosystems can be subtle; indirect effects include increased nutrient loading that could impact ecosystem function. We designed a low‐level fertilization experiment to mimic persistent, climate change‐driven disturbances (deeper thaw, greater weathering, or thermokarst failure) delivering nutrients to arctic lakes. We measured responses of pelagic trophic levels over 12 yr in a fertilized deep lake with fish and a shallow fishless lake, compared to paired reference lakes, and monitored recovery for 6 yr. Relative to prefertilization in the deep lake, we observed a maximum pelagic response in chl a (+201%), dissolved oxygen (DO, −43%), and zooplankton biomass (+88%) during the fertilization period (2001–2012). Other responses to fertilization, such as water transparency and fish relative abundance, were delayed, but both ultimately declined. Phyto‐ and zooplankton biomass and community composition shifted with fertilization. The effects of fertilization were less pronounced in the paired shallow lakes, because of a natural thermokarst failure likely impacting the reference lake. In the deep lake there was (a) moderate resistance to change in ecosystem functions at all trophic levels, (b) eventual responses were often nonlinear, and (c) postfertilization recovery (return) times were most rapid at the base of the food web (2–4 yr) while higher trophic levels failed to recover after 6 yr. The timing and magnitude of responses to fertilization in these arctic lakes were similar to responses in other lakes, suggesting indirect effects of climate change that modify nutrient inputs may affect many lakes in the future.
Nonlinear Moiré Superlattice for Super‐Resolution Nondestructive Detection of Nonlinear Photonic Crystals
Authors: Liu Haigang , Chen Xianfeng
Published: August 2021

The moiré effect is a universal phenomenon originating from the interference of waves, and it is widely applied in metrology as well as superconductor phenomena in graphene. The present study demonstrates a nonlinear moiré effect originating from the moiré superlattices of two nonlinear photonic crystals (NPCs). It is experimentally shown that these nonlinear moiré superlattices facilitate the nondestructive detection of nonlinear photonic crystals. Two identical periodically poled lithium niobates (PPLNs) are used to observe the nonlinear moiré effect originating from the nonlinear moiré superlattices. This is followed by a demonstration of the detection capability of the nonlinear optical method for dissimilar PPLNs and calculation of the period detection range. The theoretically and experimentally obtained periods of the target PPLN are consistent, and the resolution of the nonlinear moiré effect surpasses to that of presently used optical systems. Furthermore, the detection range of the nonlinear moiré effect enables the sub‐micrometer‐ and nanometer‐scale detection of the nonlinear photonic crystal structure using only an optical microscope. The present study conceptually extends the conventional moiré lattice to nonlinear optics, and it can also be extended to other fields where nonlinear effects cannot be avoided, such as polaritons and Bose–Einstein condensates.
Pulsed‐Laser Detectors Based on Metal Halide Perovskites
Authors: Xu Yalun , Li Wei , Yu Tian , Li Yanyan , Li Ruiming , Lin Qianqian
Published: August 2021

Conventionally, the detection of pulsed‐lasers is mainly based on thermal effects, such as thermoelectric detectors and pyroelectric detectors, which possess a photothermal conversion process, resulting in slow response and significant energy loss. Fast photodiodes are also introduced to calibrate pulsed‐lasers. However, they require advanced oscilloscopes with high bandwidth and amplification systems, limiting their practical application to some extent. To address the issues of these two types of pulsed‐laser detectors, an interfacial modification strategy is introduced to the conventional perovskite photodiodes. The incorporation of the polyvinylidene fluoride layer can effectively slow down the photovoltage decay of the perovskite devices via electric‐field induced polarization, which enables the detection of both modulated light emitting diodes and ultra‐fast pulsed‐lasers in a facile way. With such effect, the polyvinylidene fluoride (PVDF) based photodetectors can effectively convert the pulsed light input to a quasi‐DC output, which can be easily recorded with a multimeter or source meter. These devices also exhibit low noise voltage of <10−5 V Hz−1/2, high responsivity of >2 × 104 V W−1 @ 1 µW cm−2, indicating great potential for real applications.
In Vivo Versus In Vitro Degradation of a 3D Printed Resorbable Device for Ligation of Vascular Tissue in Horses
Authors: Adolfsson Karin H. , Sjöberg Ida , Höglund Odd V. , Wattle Ove , Hakkarainen Minna
Published: August 2021

A resorbable 3D printed polydioxanone (PDO) device is manufactured to facilitate ligation of vascular tissue during surgery. The device must provide sufficient mechanical performance throughout the healing period. Therefore, degradation and mechanical performance of the device are investigated as a function of in vivo and in vitro aging. During aging the PDO device released cyclic and linear water‐soluble products. In vivo aging resulted in higher relative number of linear oligomers in comparison to in vitro aging. A major loss of mechanical performance is observed after only 10 days in vivo and the Young’s modulus (E) and tensile strength at break (σb) decreased by 28% and 54%, respectively. This is in contrast to in vitro aging, where no loss of mechanical properties is observed during the same period. The in vivo aged devices exhibit clear holes in the matrices after 28 days, while apparent cracks are observed first after 140 days in vitro. These results highlight the sensitivity of the degradation process of resorbable devices with regards to the interactions of the device with the surrounding environment (tissues) and demonstrate the importance of in vivo testing as compliment to in vitro testing before clinical use of devices.
Stimuli‐Responsive Depolymerization of Poly(Phthalaldehyde) Copolymers and Networks
Authors: Soars Shafer , Kamps Joshua , Fairbanks Benjamin , Bowman Christopher
Published: August 2021

This article describes a stimuli‐responsive cross‐linked network based on a poly(phthalaldehyde) (PPA) self‐immolating polymer backbone which, upon removal of polymer end‐caps, becomes degradable under ambient conditions. Self‐immolating polymers (SIPs) are of particular interest due to their ability to undergo controlled depolymerization resulting in the elimination of the polymer structure and potential recovery and reuse of the original monomers. Linear copolymers of phthalaldehyde and unsymmetrical allylated‐phthalaldehyde monomers are obtained via anionic polymerization with appreciable incorporation of the allyl‐functional monomeric units. This approach enables crosslinking of the otherwise linear polymers via thiol–ene reactions with the allyl functional phthalaldehyde polymers. The polymer network thus formed unzips along the phthalaldehyde backbone to yield monomers and low molecular weight fragments in response to chemical (F−, H+) or physical (light, sonication) stimuli that remove the stabilizing functional endcaps on the phthalaldehyde polymers. Rheology is used to demonstrate gelation within 5 s of light exposure of the allylated‐phthalaldehyde polymers reacted with pentaerythritol tetrakis(3‐mercaptopropionate) and photoinitiator (3 wt%). Triggerable degelation makes this material well suited for photolithography and additive manufacturing as well as other applications that necessitate polymer network degradation or elimination. Further, a method is described for determining the degelation temperature of a self‐immolative cross‐linked network.
ABA Type Amphiphiles with Poly(2‐benzhydryl‐2‐oxazine) Moieties: Synthesis, Characterization and Inverse Thermogelation
Authors: Hahn Lukas , Keßler Larissa , Polzin Lando , Fritze Lars , Forster Stefan , Helten Holger , Luxenhofer Robert
Published: August 2021

Thermoresponsive polymers are frequently involved in the development of materials for various applications. Here, polymers containing poly(2‐ benzhydryl‐2‐oxazine) (pBhOzi) repeating units are described for the first time. The homopolymer pBhOzi and an ABA type amphiphile comprising two flanking hydrophilic A blocks of poly(2‐methyl‐2‐oxazoline) (pMeOx) and the hydrophobic aromatic pBhOzi central B block (pMeOx‐b‐pBhOzi‐b‐pMeOx) are synthesized and the latter is shown to exhibit inverse thermogelling properties at concentrations of 20 wt.% in water. This behavior stands in contrast to a homologue ABA amphiphile consisting of a central poly(2‐benzhydryl‐2‐oxazoline) block (pMeOx‐b‐pBhOx‐b‐pMeOx). No inverse thermogelling is observed with this polymer even at 25 wt.%. For 25 wt.% pMeOx‐b‐pBhOzi‐b‐pMeOx, a surprisingly high storage modulus of ≈22 kPa and high values for the yield and flow points of 480 Pa and 1.3 kPa are obtained. Exceeding the yield point, pronounced shear thinning is observed. Interestingly, only little difference between self‐assemblies of pMeOx‐b‐pBhOzi‐b‐pMeOx and pMeOx‐b‐pBhOx‐b‐pMeOx is observed by dynamic light scattering while transmission electron microscopy images suggest that the micelles of pMeOx‐b‐pBhOzi‐b‐pMeOx interact through their hydrophilic coronas, which is probably decisive for the gel formation. Overall, this study introduces new building blocks for poly(2‐oxazoline) and poly(2‐oxazine)‐based self‐assemblies, but additional studies will be needed to unravel the exact mechanism.
Catalytic Activity of Various β‐Diketiminate Zinc Complexes toward the Ring‐Opening Polymerization of Caprolactone and Derivatives
Authors: Köhler Moritz , Rinke Philipp , Fiederling Kevin , Görls Helmar , Ueberschaar Nico , Schacher Felix Helmut , Kretschmer Robert
Published: August 2021

The ring‐opening polymerization (ROP) of lactones is mainly catalyzed by tin(II) octanoate Sn(Oct)2, due to its efficiency and easy handling despite the toxic issues of tin. Herein, two novel dinuclear bis(β‐diketiminate) complexes with flexible alkylene bridging groups (1,2‐ethylene and 1,3‐propylene) and biocompatible zinc centers are introduced. The complexes are obtained by deprotonation of the protio‐ligands with Zn(HMDS)2 and fully characterized. Afterwards the complexes are studied regarding their catalytic activity towards the ROP of caprolactones. Briefly, ε‐caprolactone (CL), ε‐phenyl‐ε‐caprolactone (phCL) and ε‐methyl‐ε‐caprolactone (meCL) with and without benzyl alcohol (BnOH) as initiator in toluene are homopolymerized and compared to the known dinuclear 1,4‐phenylene bridged bis(β‐diketiminate) zinc catalyst and the mononuclear counterpart. Thereby, the catalysts are classified upon their efficiency by in situ IR measurements, selectivity, and polymerization control by size exclusion chromatography (SEC) of samples, which are terminated at 60% conversion. The novel zinc catalysts prevent Sn(Oct)2 typical molar mass broadening, show slower reaction rates than 1,4‐phenylene bridged bis(β‐diketiminate) and improve control compared to the mononuclear relative. However, a drastic loss of polymerization control resulting in high molar masses and polydispersities occurrs in the absence of BnOH. Furthermore, these complexes allow the ROP of phCL but are inactive for meCL.
Room‐Temperature Solid‐State Lithium Metal Batteries Using Metal Organic Framework Composited Comb‐Like Methoxy Poly(ethylene glycol) Acrylate Solid Polymer Electrolytes
Authors: Lei Zhiwen , Qiu Qi , Shen Jinlai , Ao Xiaohu , Zhang Bingqi , Guo Yuanfa , Wang Jun , Deng Yonghong , Wang Chaoyang
Published: August 2021

Solid polymer electrolyte with good thermal stability and flexibility is an excellent candidate for solid‐state lithium metal batteries, while its low ionic conductivity caused by high crystallinity limits its application at ambient temperature. Here a metal organic framework (zeolitic imidazolate framework‐8, ZIF‐8) composited comb‐like methoxy poly(ethylene glycol) acrylate polymer electrolyte (MCPE) with high ionic conductivity (9.96 × 10−5 S cm−1 at 30 °C) is prepared by an in situ UV polymerization method. The as‐prepared MCPE exhibits improved mechanical property due to the introduction of porous ZIF‐8 nanofillers, which is beneficial to suppress the growth of lithium dendrites. Consequently, the LiFePO4||MCPE||Li cells show a high capacity of 116 mAh g−1 at 30 °C and 0.5 C, and maintain 89.4% of initial capacity after 150 cycles with the average Coulombic efficiency of 99.9%. These results demonstrate that the MCPE shows great potential in solid‐state lithium metal batteries near room temperature.
Highly Stretchable, Tough, and Conductive Ag@Cu Nanocomposite Hydrogels for Flexible Wearable Sensors and Bionic Electronic Skins
Authors: Chen Kai , Hu Yunping , Liu Mingxiang , Wang Feng , Liu Pei , Yu Yongsheng , Feng Qian , Xiao Xiufeng
Published: August 2021

Flexible conductive materials and flexible electronic devices are driving the development of the next generation of cutting‐edge wearable electronics. However, the existing hydrogel‐based flexible conductive materials have limited tensile capacity, low toughness, and poor anti‐fatigue performance, resulting in narrow sensing area and insufficient durability. In this paper, a conductive nanocomposite hydrogel with high ductility, toughness, and fatigue resistance is prepared by combining silver coated copper (Ag@Cu) nanoparticles with gelatin followed by one‐step immersion in sodium sulfate (Na2SO4) solution. The salting‐out of gelatin in Na2SO4 solution greatly improve the mechanical properties of this gelatin‐based hydrogel. The uniform distribution of Ag@Cu nanoparticles inside the whole hydrogel endow the composite hydrogel with excellent electrical conductivity (1.35 S m−1). In addition, it displayed high and stable tensile strain sensitivity over a wide strain range (gauge factor = 2.08). Therefore, the Ag@Cu‐Gel hydrogel is sensitive and stable enough to be successfully utilized as flexible wearable sensor for detecting human motion signals in real time, such as bending of human joints, swallowing, and throat vocalization. Furthermore, this hydrogel is also suitable for application as electronic skin for bionic robots. The above results demonstrate the promising application of Ag@Cu‐Gel hydrogel for wearable electronics.
Defect distribution index: A novel metric for functional lung MRI in cystic fibrosis
Authors: Valk Anne , Willers Corin , Shahim Kamal , Pusterla Orso , Bauman Grzegorz , Sandkühler Robin , Bieri Oliver , Wyler Florian , Latzin Philipp
Published: August 2021

Purpose

Lung impairment from functional MRI is frequently assessed as defect percentage. The defect distribution, however, is currently not quantified. The purpose of this work was to develop a novel measure that quantifies how clustered or scattered defects in functional lung MRI appear, and to evaluate it in pediatric cystic fibrosis.

Theory

The defect distribution index (DDI) calculates a score for each lung voxel categorized as defected. The index increases according to how densely and how far an expanding circle around a defect voxel contains more than 50% defect voxels.

Methods

Fractional ventilation and perfusion maps of 53 children with cystic fibrosis were previously acquired with matrix pencil decomposition MRI. In this work, the DDI is compared to a visual score of 3 raters who evaluated how clustered the lung defects appear. Further, spearman correlations between DDI and lung function parameters were determined.

Results

The DDI strongly correlates with the visual scoring (r = 0.90 for ventilation; r = 0.88 for perfusion; P < .0001). Although correlations between DDI and defect percentage are moderate to strong (r = 0.61 for ventilation; r = 0.75 for perfusion; P < .0001), the DDI distinguishes between patients with comparable defect percentage.

Conclusion

The DDI is a novel measure for functional lung MRI. It provides complementary information to the defect percentage because the DDI assesses defect distribution rather than defect size. The DDI is applicable to matrix pencil MRI data of cystic fibrosis patients and shows very good agreement with human perception of defect distributions.
Evaluation of Supplemental Crappie Stocking in Small Southern Reservoirs
Authors: Haley Bryant M. , Wesley Neal J.
Published: August 2021

Supplemental stocking of crappie is a primary management strategy in many small southern reservoirs, but survival and contribution to the year-class in these systems is not known. We assessed the contribution of hatchery fish to the age-1 year-class within established crappie populations in four reservoirs ranging 29–74 ha in surface area. Chemically marked White Crappie Pomoxis annularis and magnolia crappie (Black Crappie Pomoxis nigromaculatus × ♀White Crappie) were stocked at 125 fish/ha in 2015 and 2016, respectively. We also stocked a renovated reservoir (40 ha) with White Crappie in 2015 to serve as a reference without intraspecific competition and to provide an estimate of marking efficacy and mark retention. The total length of wild age-0 fish at the time of stocking averaged 52–60 mm larger than that of their hatchery conspecifics. We only recaptured 11 marked crappie, 10 of which were from the reference reservoir. The recovery of only one hatchery fish from the supplemental stockings yielded a combined stocking contribution of 0.59%, or 0.71% when adjusted for marking efficacy (at least 83%). We concluded that supplemental stocking of crappie in smaller reservoirs is not effective under current the stocking protocols, as contributions <1% cannot justify hatchery and personnel costs. It may be possible to modify the stocking procedures, and potential modifications are discussed.
Combination and development of carbon filament tows: Application of coextrusion with long fiber‐reinforced thermoplastics
Authors: Lin Mei‐Chen , Lin Jia‐Horng , Bao Limin
Published: August 2021

In this study, long fiber‐reinforced thermoplastics (LFT) and coextrusion are applied to wrap carbon fiber tows in a thermoplastic polyurethane (TPU) outer layer. In this way, the proposed wrapped yarns have a sheath–core structure. Scanning electron microscopy observation reveals that TPU and carbon fiber tows form a physical combination that allows TPU to further enhance the tensile strength of carbon fiber tows by 35.87%, which is 19.62 ± 1.88 MPa. The tensile strain of carbon fiber tows also improves. LFT and coextrusion are performed to produce successive carbon fiber tows that can be successfully fabricated into textiles, possessing good fabric flexibility. The technique of carbon fiber tows can be applied to mass production feasibility for the field of carbon fiber composites.
Registration of three Arkot 0908 cotton germplasm lines
Authors: Bourland Fred M. , Chee Peng , Jones Don C.
Published: August 2021

Arkot 0908‐52 (Reg. no. GP‐1091, PI 697035), Arkot 0908‐56 (Reg. no. GP‐1090, PI 697034), and Arkot 0908‐60 (Reg. no. GP‐1089, PI 697033) are conventional cotton (Gossypium hirsutum L.) germplasm lines released by the Arkansas Agricultural Experiment Station in October 2020. The lines are high performing, early maturing germplasm derived from parents (‘GA 230’ and ‘UA222’) having contrasting backgrounds and maturity. The lines produced higher lint yields than UA222 and ‘UA48’ over 5 yr and at four test sites in Arkansas, producing similar relative lint yields across all test sites and about 15 and 25% higher than lint yields of UA222 and UA48, respectively. Additionally, they had smaller seed while producing more seed per area and more or equal amount of lint per seed than UA222 or UA48. Arkot 0908‐52 and Arkot 0908‐60 performed well in the 2017 Regional High Quality Test and the 2017 Regional Breeders Network Test, respectively. Leaf pubescence and bract trichome density of Arkot 0908‐56 were greater than Arkot 0908‐52, Arkot 0908‐60, and UA48. Stem pubescence density of Arkot 0908‐52 and Arkot 0908‐56 was similar to UA48 and UA222 but greater than Arkot 0908‐60. All three lines displayed high resistance to bacterial blight and were similar to UA222 and UA48 in their response to other diseases. Arkot 0908‐56 and Arkot 0908‐60 were more resistant to tarnished plant bug than Arkot 0908‐52 and UA48, but all were more susceptible to tarnished plant bug than UA222. Fiber quality of Arkot 0908‐52 and Arkot 0908‐56 was similar to UA48, while fiber quality of Arkot 0908‐60 was similar to UA222.
Modulating Endogenous Oxygen Consumption Enhanced AIEgens‐Mediated Photodynamic Therapy against Advanced Bladder Tumor
Authors: Hao Jiange , Yin Haoli , Lu Wenfeng , Zhuang Junlong , Chen Mengxia , Gao Jie , Zhu Guanchen , Cao Wenmin , Kan Yansheng , Lu Yingqiang , Guo Hongqian
Published: August 2021

Photodynamic therapy (PDT) plays an important role in tumor therapy. However, PDT outcomes remain poor due to the insufficient reactive oxygen species (ROS) yield of the photosensitizer and the aggravation of hypoxia in the tumor microenvironment through PDT. To solve this issue, a puissant PDT nanoparticles (NPs) platform is developed to defeat tumors by employing powerful PDT in an oxygen‐enriched tumor microenvironment and by inhibiting tumor migration through regulating hypoxia‐related pathways. Specifically, TFM, as a previously reported AIEgen, does not emit brightly but instead makes use of its nonradiative relaxation for ROS generation, along with oxygen regulator doxycycline (DOXY), both of which are encapsulated in NPs that can specifically penetrate deep into tumor tissue. After released from the NPs, TFM functions as a powerful ROS generator, and DOXY reduces endogenous oxygen consumption via regulating mitochondrial cytochrome oxidase 1, further enhancing TFM‐mediated PDT efficacy. Meanwhile, reoxygenation is observed to reduce the expression of hypoxia inducible factor‐1α and M2 macrophages induced by PDT. The amplified PDT not only strongly killed tumor but, along with the downregulated hypoxia related pathways during the post‐PDT process, inhibited tumor migration. In summary, such NPs exhibit potent anti‐tumor effects for advanced bladder cancer therapy.
An overview on the seven pathogenic human coronaviruses
Authors: Kesheh Mina Mobini , Hosseini Parastoo , Soltani Saber , Zandi Milad
Published: August 2021

To date, seven human coronaviruses (HCoVs) have been detected: HCoV‐NL63, HCoV‐229E, HCoV‐HKU1, HCoV‐OC43, severe acute respiratory syndrome coronavirus (SARS‐CoV), Middle East respiratory syndrome coronavirus (MERS‐CoV) and SARS‐CoV‐2. Four of these viruses, including HCoV‐NL63, ‐229E, ‐HKU1 and ‐OC43, usually cause mild‐to‐moderate respiratory diseases with a seasonal pattern. Since 2000, three new HCoVs have emerged with a significant mortality rate. Although SARS‐CoV and MERS‐CoV caused an epidemic in some countries, SARS‐CoV‐2 escalated into a pandemic. All HCoVs can cause severe complications in the elderly and immunocompromised individuals. The bat origin of HCoVs, the presence of intermediate hosts and the nature of their viral replication suggest that other new coronaviruses may emerge in the future. Despite the fact that all HCoVs share similarities in viral replication, they differ in their accessory proteins, incubation period and pathogenicity. This study aims to review these differences between the seven HCoVs.
Systematic review of host genetic association with Covid‐19 prognosis and susceptibility: What have we learned in 2020?
Authors: Ferreira de Araújo João Locke , Menezes Diego , Saraiva‐Duarte Julia Maria , de Lima Ferreira Luciana , Santana de Aguiar Renato , Pedra de Souza Renan
Published: August 2021

Biomarker identification may provide strategic opportunities to understand disease pathophysiology, predict outcomes, improve human health, and reduce healthcare costs. The highly heterogeneous Covid‐19 clinical manifestation suggests a complex interaction of several different human, viral and environmental factors. Here, we systematically reviewed genetic association studies evaluating Covid‐19 severity or susceptibility to SARS‐CoV‐2 infection following PRISMA recommendations. Our research comprised papers published until December 31st, 2020, in PubMed and BioRXiv databases focusing on genetic association studies with Covid‐19 prognosis or susceptibility. We found 20 eligible genetic association studies, of which 11 assessed Covid‐19 outcome and 14 evaluated infection susceptibility (five analyzed both effects). Q‐genie assessment indicated moderate quality. Five large‐scale association studies (GWAS, whole‐genome, or exome sequencing) were reported with no consistent replication to date. Promising hits were found on the 3p21.31 region and ABO locus. Candidate gene studies examined ACE1, ACE2, TMPRSS2, IFITM3, APOE, Furin, IFNL3, IFNL4, HLA, TNF‐ɑ genes, and ABO system. The most evaluated single locus was the ABO, and the most sampled region was the HLA with three and five candidate gene studies, respectively. Meta‐analysis could not be performed. Available data showed the need for further reports to replicate claimed associations.
Optimal game theoretic solution of the pursuit‐evasion intercept problem using on‐policy reinforcement learning
Authors: Kartal Yusuf , Subbarao Kamesh , Dogan Atilla , Lewis Frank
Published: August 2021

This article presents a rigorous formulation for the pursuit‐evasion (PE) game when velocity constraints are imposed on agents of the game or players. The game is formulated as an infinite‐horizon problem using a non‐quadratic functional, then sufficient conditions are derived to prove capture in a finite‐time. A novel tracking Hamilton–Jacobi–Isaacs (HJI) equation associated with the non‐quadratic value function is employed, which is solved for Nash equilibrium velocity policies for each agent with arbitrary nonlinear dynamics. In contrast to the existing remedies for proof of capture in PE game, the proposed method does not assume players are moving with their maximum velocities and considers the velocity constraints a priori. Attaining the optimal actions requires the solution of HJI equations online and in real‐time. We overcome this problem by presenting the on‐policy iteration of integral reinforcement learning (IRL) technique. The persistence of excitation for IRL to work is satisfied inherently until capture occurs, at which time the game ends. Furthermore, a nonlinear backstepping control method is proposed to track desired optimal velocity trajectories for players with generalized Newtonian dynamics. Simulation results are provided to show the validity of the proposed methods.
Testing and correcting for weak and pleiotropic instruments in two‐sample multivariable Mendelian randomization
Authors: Sanderson Eleanor , Spiller Wes , Bowden Jack
Published: August 2021

Multivariable Mendelian randomization (MVMR) is a form of instrumental variable analysis which estimates the direct effect of multiple exposures on an outcome using genetic variants as instruments. Mendelian randomization and MVMR are frequently conducted using two‐sample summary data where the association of the genetic variants with the exposures and outcome are obtained from separate samples. If the genetic variants are only weakly associated with the exposures either individually or conditionally, given the other exposures in the model, then standard inverse variance weighting will yield biased estimates for the effect of each exposure. Here, we develop a two‐sample conditional F‐statistic to test whether the genetic variants strongly predict each exposure conditional on the other exposures included in a MVMR model. We show formally that this test is equivalent to the individual level data conditional F‐statistic, indicating that conventional rule‐of‐thumb critical values of 10, can be used to test for weak instruments. We then demonstrate how reliable estimates of the causal effect of each exposure on the outcome can be obtained in the presence of weak instruments and pleiotropy, by repurposing a commonly used heterogeneity Q‐statistic as an estimating equation. Furthermore, the minimized value of this Q‐statistic yields an exact test for heterogeneity due to pleiotropy. We illustrate our methods with an application to estimate the causal effect of blood lipid fractions on age‐related macular degeneration.
Bio‐waste Derived Catalytic Approach Towards NH‐1,2,3‐Triazole Synthesis
Authors: Garg Anirban , Hazarika Roktopol , Dutta Nilakshi , Dutta Bidyutjyoti , Sarma Diganta
Published: August 2021

A bio‐waste derived catalyst towards the synthesis of 4‐aryl‐NH‐1,2,3‐triazole is reported. Curd whey is the major by‐product produced from dairy industry which is mostly discarded to water or used as fertilizer and animal feed after drying. Here, whey is used as an efficient bio‐waste derived catalyst for straight forward synthesis of NH‐1,2,3‐triazoles under very mild condition. Current method is highly versatile, inexpensive, offers various NH‐1,2,3‐triazoles in good to excellent yields. The solvent‐catalyst combination can be effectively reused up to 4th consecutive cycles without significant loss in its catalytic efficiency.
Recent Progress on the Scanning Tunneling Microscopy and Spectroscopy Study of Semiconductor Heterojunctions
Authors: Peng Wenbing , Wang Haolin , Lu Hui , Yin Lei , Wang Yue , Grandidier Bruno , Yang Deren , Pi Xiaodong
Published: August 2021

The band alignment, interface states, interface coupling, and carrier transport of semiconductor heterojunctions (SHs) need to be well understood for the design and fabrication of various important semiconductor structures and devices. Scanning tunneling microscopy (STM) with high spatial resolution and scanning tunneling spectroscopy (STS) with high energy resolution are significantly contributing to the understanding on the important properties of SHs. In this work, the recent progress on the use of STM and STS to study lateral, vertical and bulk SHs is reviewed. The spatial structures of SHs with atomically flat surface have been examined with STM. The electronic band structures (e. g., the band offset, interface state, and space charge region) of SHs are measured with STS. Combined with the spatial structures and the tunneling spectra features, the mechanism for the carrier transport in the SH may be proposed.
Oxygen Defect Engineering of β‐MnO2 Catalysts via Phase Transformation for Selective Catalytic Reduction of NO
Authors: Yang Runnong , Peng Shaomin , Lan Bang , Sun Ming , Zhou Zihao , Sun Changyong , Gao Zihan , Xing Guichuan , Yu Lin
Published: August 2021

The catalysts for low‐temperature selective catalytic reduction of NO with NH3 (NH3‐SCR) are highly desired due to the large demand in industrial furnaces. The characteristic of low‐temperature requires the catalyst with rich active sites especially the redox sites. Herein, the authors obtain oxygen defect‐rich β‐MnO2 from a crystal phase transformation process during air calcination, by which the as‐prepared γ‐MnO2 nanosheet and nanorod can be conformally transformed into the corresponding β‐MnO2. Simultaneously, this transformation accompanies oxygen defects modulation resulted from lattice rearrangement. The most active β‐MnO2 nanosheet with plentiful oxygen defects shows a high efficiency of > 90% NO conversion in an extremely wide operation window of ≈120–350 °C. The detailed characterizations and density functional theory (DFT) calculations reveal that the introduction of oxygen defects enhances the adsorption properties for reactants and decreases the energy barriers of *NH2 formation more than 0.3 eV (≈0.32–0.37 eV), which contributes to a high efficiency of low‐temperature SCR activity. The authors finding provides a feasible approach to achieve the oxygen defect engineering and gains insight into manganese‐based catalysts for low‐temperature NO removal or pre‐oxidation.
High‐Performance MnO2/Al Battery with In Situ Electrochemically Reformed AlxMnO2 Nanosphere Cathode
Authors: Pan Wending , Mao Jianjun , Wang Yifei , Zhao Xiaolong , Leong Kee Wah , Luo Shijing , Chen Yue , Leung Dennis Y. C.
Published: August 2021

Aqueous Al–ion battery (AAIB) is regarded as a promising candidate for large‐scale energy storage systems due to its high capacity, high safety, and low cost, with MnO2 proved to be a high‐performance cathode. However, the potential commercial application of this type of battery is plagued by the frequent structural collapse of MnO2. Herein, an in situ, electrochemically reformed, urchin‐like AlxMnO2 cathode is developed for water‐in‐salt electrolyte‐based AAIBs. Benefiting from its unique α‐MnO2 coated Mn2AlO4 structure, a high Al ion storage capacity is achieved together with a high discharge voltage plateau of 1.9 V by reversible MnO2 electrolysis. Consequently, the battery exhibits a high specific capacity of 285 mAh g–1 and a high energy density of 370 Wh kg–1 at a high current density of 500 mA g–1. Improved stability with record capacity retention is also obtained at an ultrahigh current density of 5 A g–1 after 500 cycles. Such a high‐capacity and high‐stability AlxMnO2 cathode would pave the way for in situ electrochemical transformation of cathode design and thus boost the practical application of AAIBs.
Characterization of heterosis and genomic prediction‐based establishment of heterotic patterns for developing better hybrids in pigeonpea
Authors: Saxena Rachit K. , Jiang Yong , Khan Aamir W , Zhao Yusheng , Kumar Singh Vikas , Bohra Abhishek , Sonappa Muniswamy , Rathore Abhishek , Kumar C.V. Sameer , Saxena Kulbhushan , Reif Jochen , Varshney Rajeev K.
Published: August 2021

Whole‐genome resequencing (WGRS) of 396 lines, consisting of 104 hybrid parental lines and 292 germplasm lines, were used to study the molecular basis of mid‐parent heterosis (MPH) and to identify complementary heterotic patterns in pigeonpea [Cajanus cajan (L.) Millsp.] hybrids. The lines and hybrids were assessed for yield and yield‐related traits in multiple environments. Our analysis showed positive MPH values in 78.6% of hybrids, confirming the potential of hybrid breeding in pigeonpea. By using genome‐wide prediction and association mapping approaches, we identified 129 single nucleotide polymorphisms and 52 copy number variations with significant heterotic effects and also established a high‐yielding heterotic pattern in pigeonpea. In summary, our study highlights the role of WGRS data in the study and use of heterosis in crops where hybrid breeding is expected to boost selection gain in order to ensure global food security.
Neurocomputational models of altruistic decision‐making and social motives: Advances, pitfalls, and future directions
Authors: Tusche Anita , Bas Lisa M.
Published: August 2021

This article discusses insights from computational models and social neuroscience into motivations, precursors, and mechanisms of altruistic decision‐making and other‐regard. We introduce theoretical and methodological tools for researchers who wish to adopt a multilevel, computational approach to study behaviors that promote others' welfare. Using examples from recent studies, we outline multiple mental and neural processes relevant to altruism. To this end, we integrate evidence from neuroimaging, psychology, economics, and formalized mathematical models. We introduce basic mechanisms—pertinent to a broad range of value‐based decisions—and social emotions and cognitions commonly recruited when our decisions involve other people. Regarding the latter, we discuss how decomposing distinct facets of social processes can advance altruistic models and the development of novel, targeted interventions. We propose that an accelerated synthesis of computational approaches and social neuroscience represents a critical step towards a more comprehensive understanding of altruistic decision‐making. We discuss the utility of this approach to study lifespan differences in social preference in late adulthood, a crucial future direction in aging global populations. Finally, we review potential pitfalls and recommendations for researchers interested in applying a computational approach to their research.

This article is categorized under:

Economics > Interactive Decision‐Making

Psychology > Emotion and Motivation

Neuroscience > Cognition

Economics > Individual Decision‐Making
A Qualitative Similarity Framework for the Interpretation of Natural Language Similarity Expressions
Authors: Gust Helmar , Umbach Carla
Published: August 2021

In this paper, a representational framework is presented featuring a qualitative notion of similarity. It is aimed at issues of natural language semantics, in particular the semantics of expressions of similarity and sameness and their role in comparison and ad-hoc kind formation. The framework makes use of attribute spaces, which are well-established in AI and also in some branches of natural language semantics, e.g., frame-based approaches (Barsalou 1992). What distinguishes attribute spaces and representations as proposed in this paper is the idea of systems of predicates on attribute spaces corresponding to predicates on the domain. On the worldy side, a domain includes a set of relevant predicates talking about individuals. These predicates have counterparts on the representational side talking about points of an attribute space. Counterpart predicates are required to be consistent with their originals; more precisely, they have to agree in truth-value on the set of positive and negative exemplars thereby approximating the original predicates. Moreover, counterpart predicates will be assumed to have convex and open extensions. This system facilitates a qualitative notion of similarity which is suited to account for the meaning of natural language similarity expressions and, furthermore, their role in comparison and ad-hoc kind formation.
Lower BAFF Levels in Myasthenic Patients Treated with Glucocorticoids
Authors: Sobieszczuk Ewa , Szczudlik Piotr , Kubiszewska Justyna , Szyluk Beata , Lipowska Marta , Dutkiewicz Małgorzata , Kostera-Pruszczyk Anna
Published: August 2021

B-cell activating factor (BAFF), a member of tumor necrosis factor family, activates B cells, promotes their survival and proliferation. BAFF is considered to have an influence on development of autoimmune diseases including myasthenia gravis (MG). We aimed to evaluate BAFF serum levels in MG patients, their potential connection with therapy and course of MG. Cross-sectional study. Two hundred eighteen adult patients with MG (67% women, age: 18–89 years, 82.6% AChR antibody seropositive (AChRAb(+)). Serum BAFF levels, their relationship with severity of clinical symptoms, therapy conducted, clinical and demographic features and other factors were analyzed. Patients with AChRAb(+) MG demonstrated significantly higher BAFF levels than MuSK-MG patients (831.2 ± 285.4 pg/ml vs. 745.6 ± 633.4 pg/ml, respectively; p = 0.030). Serum BAFF levels in women were significantly higher than in men (855.9 ± 302.5 vs. 756.6 ± 289.4, respectively; p = 0.017). Mean serum BAFF level was significantly decreased in patients who were ever treated with corticosteroids (CS) (770.4 ± 327.8 pg/ml vs. 891.3 ± 246.1 pg/ml, respectively; p = 0.001). Thymoma-MG patients demonstrated significantly lower BAFF levels (671.2 ± 244.9 vs. 833.5 ± 302.4, respectively; p = 0.044). Thymectomized patients did not differ in BAFF levels from the MG patients who had not undergone thymectomy. In multiple linear regression model, recent CS therapy and male sex were found to be independent predictors of lower BAFF levels. Serum BAFF level is decreased in patients treated with CS, which may suggest inhibiting influence of CS on BAFF—a potential mechanism contributing to the effectiveness of such therapy.
The horizontal shear fracture of the pelvis
Authors: Johns Brenton P. , Balogh Zsolt J.
Published: August 2021

Purpose

Various classification systems describe fractures of the acetabulum and pelvis separately. Horizontal shear fractures involve the pelvic ring and both acetabula and have not been previously described. The aim of this study is to describe the horizontal shear fracture of the pelvis.

Methods

At a level 1 trauma centre over 10 years from December 2008 to December 2018, 1242 patients had pelvic and acetabular fractures. Six patients had horizontal shear fractures, comprising 0.5% of all pelvic and acetabular fractures. Demographic, clinical and radiological data was collected. Clinical outcomes were pain and mobility level, sciatic nerve symptoms, further acetabular or pelvic surgery, or total hip arthroplasty. Radiological outcomes included fracture displacement, implant migration, femoral head osteonecrosis, and post-traumatic arthritis. Outcomes were assessed at a minimum 12 month follow-up.

Results

The median patient age was 35 years. Five of six shear fractures were due to motorcycle crashes. No mortalities occurred. At follow-up, three patients reported pain, two patients had difficulty mobilising associated with traumatic sciatic nerve injury, and one patient underwent total hip arthroplasty for femoral head osteonecrosis. No fracture displacement or implant migration occurred. The Matta arthritis grade was excellent or good in all except one hip. Median follow-up time was 1.8 (range 1.1–7.8) years.

Conclusion

The horizontal shear fracture of the pelvis is a high-energy injury characterised by separation of the anterior and posterior pelvic ring through the acetabula. Good outcomes can be achieved with open reduction and internal fixation of displaced fractures.
COVID-19: eine Chance zur Digitalisierung der Lehre?
Authors: Hempel Gunther , Weissenbacher Andreas , Stehr Sebastian N.
Published: August 2021

Hintergrund

Die SARS-CoV-2-Pandemie hat die Universitäten vor große Herausforderungen gestellt. Innerhalb kürzester Zeit galt es, Lehrveranstaltungen zu digitalisieren. Dies betraf auch den Bereich Anästhesiologie, Intensiv‑, Notfall‑, Schmerz- und Palliativmedizin an der Universität Leipzig.

Fragestellung

Ziel der fragebogengestützten Untersuchung war es herauszufinden, welche Veranstaltungen aus Sicht der Studierenden am ehesten digitalisiert werden können, und welche technische Infrastruktur die Lehrenden bei der Digitalisierung jeweils bestmöglich unterstützt.

Material und Methoden

Für die digitale Durchführung der Lehrveranstaltungen wurden Videopodcasts, digitale Lernmaterialien, Lehrfilme und Videokonferenzen genutzt. Je nach Veranstaltung wurden verschiedene dieser Angebote kombiniert. Darüber hinaus wurde ein Diskussionsforum für den Austausch zwischen Lehrenden und Studierenden etabliert. Zur Bewertung der Inhalte erfolgte im Anschluss eine Onlineevaluation.

Ergebnisse

An der Befragung haben 82 Studierende teilgenommen. Als effektivste Angebote zur Wissensvermittlung wurden die Videopodcasts der Vorlesung (45,1 %) sowie der elektronische Unterricht am Krankenbett (34,1 %) bewertet. Insbesondere die Vorlesungen könnten nach Meinung von 92,7 % der befragten Studierenden auch dauerhaft digital ersetzt werden. Knapp 90 % haben die digitalen Lehrangebote der Klinik mit einer Gesamtnote von 1 oder 2 bewertet.

Diskussion und Zusammenfassung

Im Zuge des digitalen Semesters ließen sich einzelne Lehrformate unterschiedlich gut digitalisieren: Vorlesungen können aus Sicht der Studierenden auch langfristig besonders gut digital abgebildet werden, währenddessen die Digitalisierung des Unterrichts am Krankenbett bisher nicht adäquat möglich ist.
Ischämische Hirninfarkte bei Coronavirus-19-Erkrankung
Authors: Sander Paulina Laura , Cleff Ulrich , Larrossa-Lombardi Simon , Ali Hatem , Fotiadis Panagiotis , Reimann Gernot , Rohde Stefan , Hofstadt-van Oy Ulrich
Published: August 2021

Zwei Fälle von Patienten mit der Coronavirus-19-Erkrankung (COVID-19) werden berichtet, bei denen Verschlüsse großer Hirnarterien vorlagen. Diese traten bei einer Patientin in der Früh- als auch im 2. Fall in der Spätphase der COVID-19 auf. Eine Patientin konnte erfolgreich mithilfe der i.v.-Thrombolyse und mechanischer Thrombektomie behandelt werden. Gerinnungsstörungen im Rahmen der COVID-19 können auch bei jüngeren Patienten zu fulminanten Hirninfarkten mit schlechtem Outcome führen. Bezüglich der Ätiologie dieser Gefäßverschlüsse (COVID-19-induzierte Hyperkoagulopathie, Kardiomyopathie, Vaskulitis) besteht weiterer Forschungsbedarf.