bluuebunny/crossref_metadata_2025 huggingface dataset:
Contrasting growth response of evergreen and deciduous arctic‐alpine shrub species to climate variability
Authors: Dobbert Svenja , Pape Roland , Löffler Jörg
Published: August 2021

Broad‐scale changes in arctic‐alpine vegetation and their global effects have long been recognized and labeled one of the clearest examples of the terrestrial impacts of climate change. Arctic‐alpine dwarf shrubs are a key factor in those processes, responding to accelerated warming in complex and still poorly understood ways. Here, we look closely into such responses of deciduous and evergreen species, and for the first time, we make use of high‐precision dendrometers to monitor the radial growth of dwarf shrubs at unprecedented temporal resolution, bridging the gap between classical dendroecology and the underlying growth physiology of a species. Using statistical methods on a five‐year dataset, including a relative importance analysis based on partial least squares regression, linear mixed modeling, and correlation analysis, we identified distinct growth mechanisms for both evergreen (Empetrum nigrum ssp. hermaphroditum) and deciduous (Betula nana) species. We found those mechanisms in accordance with the species respective physiological requirements and the exclusive micro‐environmental conditions, suggesting high phenotypical plasticity in both focal species. Additionally, growth in both species was negatively affected by unusually warm conditions during summer and both responded to low winter temperatures with radial stem shrinking, which we interpreted as an active mechanism of frost protection related to changes in water availability. However, our analysis revealed contrasting and inter‐annually nuanced response patterns. While B. nana benefited from winter warming and a prolonged growing season, E. hermaphroditum showed high negative sensitivity to spring cold spells after an earlier growth start, relying on additional photosynthetic opportunities during snow‐free winter periods. Thus, we conclude that climate–growth responses of dwarf shrubs in arctic‐alpine environments are highly seasonal and heterogenic, and that deciduous species are overall likely to show a positive growth response to predicted future climate change, possibly dominating over evergreen competitors at the same sites, contributing to the ongoing greening trend.
Understanding the future of big sagebrush regeneration: challenges of projecting complex ecological processes
Authors: Schlaepfer Daniel R. , Bradford John B. , Lauenroth William K. , Shriver Robert K.
Published: August 2021

Regeneration is an essential demographic step that affects plant population persistence, recovery after disturbances, and potential migration to track suitable climate conditions. Challenges of restoring big sagebrush (Artemisia tridentata) after disturbances including fire‐invasive annual grass interactions exemplify the need to understand the complex regeneration processes of this long‐lived, woody species that is widespread across the semiarid western U.S. Projected 21st century climate change is expected to increase drought risks and intensify restoration challenges. A detailed understanding of regeneration will be crucial for developing management frameworks for the big sagebrush region in the 21st century. Here, we used two complementary models to explore spatial and temporal relationships in the potential of big sagebrush regeneration representing (1) range‐wide big sagebrush regeneration responses in natural vegetation (process‐based model) and (2) big sagebrush restoration seeding outcomes following fire in the Great Basin and the Snake River Plains (regression‐based model). The process‐based model suggested substantial geographic variation in long‐term regeneration trajectories with central and northern areas of the big sagebrush region remaining climatically suitable, whereas marginal and southern areas are becoming less suitable. The regression‐based model suggested, however, that restoration seeding may become increasingly more difficult, illustrating the particularly difficult challenge of promoting sagebrush establishment after wildfire in invaded landscapes. These results suggest that sustaining big sagebrush on the landscape throughout the 21st century may climatically be feasible for many areas and that uncertainty about the long‐term sustainability of big sagebrush may be driven more by dynamics of biological invasions and wildfire than by uncertainty in climate change projections. Divergent projections of the two models under 21st century climate conditions encourage further study to evaluate potential benefits of re‐creating conditions of uninvaded, unburned natural big sagebrush vegetation for post‐fire restoration seeding, such as seeding in multiple years and, for at least much of the northern Great Basin and Snake River Plains, the control of the fire‐invasive annual grass cycle.
Intraspecific trait variation drives grassland species richness and productivity under changing precipitation
Authors: Deng Meifeng , Liu Weixing , Li Ping , Jiang Lin , Li Shaopeng , Jia Zhou , Yang Sen , Guo Lulu , Wang Zhenhua , Liu Lingli
Published: August 2021

It has been increasingly recognized that plant traits and their intraspecific variation play pivotal roles in determining how ecosystem structure and function respond to a changing environment. Yet, it remains unclear how and which plant traits regulate the assembly process and thus affect ecosystem structure and function under climate changes. Here, we selected six steppe sites with snow fences along a precipitation gradient in inner Mongolia. We measured traits including plant height and leaf carbon, nitrogen, and phosphorus concentrations. We incorporated intraspecific trait variation to quantify the strength of external filters (assembly processes outside the community at a larger spatial scale), the strength of internal filters (assembly processes within the local community), and functional redundancy (the number of species having a similar function to an ecosystem). We applied these assembly rules to explain the changes in biodiversity and productivity in response to changing precipitation. We found that increased rainfall reduced plant carbon (C), nitrogen (N), and phosphorous (P) concentrations, but did not affect plant height. High snowfall increased phosphorous concentration, but did not affect other traits. Latent variable models identified climate (rainfall) and soil nutrient conditions (soil total N and P content) were more important than external filtering processes in predicting species richness. However, external filtering processes were the most important predictor of productivity. More specifically, we found with the increase in steppe productivity, the strength of the external filtering on leaf N increased and on plant height decreased, leading to leaf N converging into a small range but broadening the range of plant height. The internal filters had no significant effects on species richness or productivity. Additionally, we found that low precipitation reduced functional redundancy. We emphasize that intraspecific trait‐variation drives plant productivity and richness responses to precipitation changes by regulating community assemblage. Our finding also underlines the importance to separate the contributions of different functional traits in regulating the responses of ecosystem structure and function to climate changes.
Identification of the Gulf of Mexico as an important high‐use habitat for leatherback turtles from Central America
Authors: Evans Daniel R. , Valverde Roldán A. , Ordoñez Cristina , Carthy Raymond R.
Published: August 2021

Endangered leatherback sea turtles (Dermochelys coriacea) are wide‐ranging, long‐distance migrants whose movements are often associated with environmental cues. We examined the spatial distribution and habitat use for 33 satellite‐tracked leatherbacks from nesting beaches on the Caribbean coast of Costa Rica and Panama from 2004 to 2018, an important nesting population for the leatherback Northwest Atlantic Distinct Population Segment. Tracking revealed the use of two distinct regions, the Gulf of Mexico (GoM, n = 18) and the North Atlantic Ocean (NAO, n = 15). We developed density utilization maps to elucidate high‐use habitats, migration pathways, and seasonal movements. GoM leatherbacks were found in three concentrated high‐use habitats connected by a migration pathway, while NAO leatherbacks were primarily found in a single, large high‐use habitat. Leatherbacks in both regions have the potential to interact with Atlantic pelagic longline fisheries based on seasonal overlap with high fishing effort. Our findings suggest that the GoM is an important destination for leatherbacks from the Caribbean coast of Central America with seasonal movements between high‐use habitats within the GoM. While leatherbacks are utilizing high‐use habitats in both the NAO and the GoM, the proportion of individuals migrating into the GoM increased over the study period. Additionally, NAO leatherbacks have increased the distance they travel in the first 90 d. Regional differences in movement and spatial distribution of high‐use habitats are important considerations when developing conservation plans for the Northwest Atlantic leatherback population.
The Elemental Multifariousness of the Defect‐Pyrochlore Crystal Structure and Application in Photocatalytic Hydrogen Generation
Authors: Weiss Morten , Hoerner Gerald , Weber Birgit , Marschall Roland
Published: August 2021

Tungsten‐based defect‐pyrochlores CsM
x
W2−x
O6 are used as model oxides to investigate the high number of possible M cations that can be used to form the defect‐pyrochlore crystal structure. A large variety of possible compounds are presented, several of which have been unknown so far. These compounds are used in photocatalytic hydrogen evolution to investigate possible correlations between the photocatalytic activity and the varying elemental compositions.
Experimental investigation of self‐centering hybrid concrete shear walls subjected to horizontal cyclic loading
Authors: Liu Yang , Zhou Wei
Published: August 2021

As an effective way to facilitate functional recovery, self‐centering structures are gaining increased attention from researchers. Extensive experimental studies of self‐centering concrete shear walls have been conducted in recent decades, but there are still a limited number of full‐scale tests assessing the stiffness, ductility, and tendon stress variation. In this study, the seismic performance of self‐centering concrete shear walls was investigated. Full‐scale tests of seven cantilever walls were conducted under a constant gravity load, including six self‐centering shear walls and one cast‐in situ shear wall. The failure modes of the cast‐in situ wall and the self‐centering walls were compared, and different indices representing the seismic performance were calculated and analyzed further, such as the stiffness, ductility, residual drift, contact length, tendon stress variation, and the energy‐dissipating capacity, to present a full assessment of the seismic performance of the self‐centering concrete shear walls. It was found that although the longitudinal bars and concrete were terminated at the wall base joint, the self‐centering walls showed comparable stiffness and larger ductility than the cast‐in situ wall, and sufficient dissipating capacity to resist seismic events. Also, the tendons worked elastically to provide a stable contribution to the self‐centering ability.
Lactobacillus casei relieves liver injury by regulating immunity and suppression of the enterogenic endotoxin‐induced inflammatory response in rats cotreated with alcohol and iron
Authors: Li Xuelong , Han Jianmin , Liu Ying , Liang Hui
Published: August 2021

Excessive alcohol and iron intake can reportedly cause liver damage. In the present study, we investigated the effect of Lactobacillus casei on liver injury in rats co‐exposed to alcohol and iron and evaluated its possible mechanism. Sixty male Wistar rats were randomly divided into three groups for 12 weeks: the Control group (administered normal saline by gavage and provided a normal diet); alcohol +iron group (Model group, treated with alcohol [3.5–5.3 g/kg/day] by gavage and dietary iron [1,500 mg/kg]); Model group supplemented with L. casei (8 × 108 CFU kg−1 day−1) (L. casei group). Using hematoxylin and eosin (HE) staining and transmission electron microscopy, we observed that L. casei supplementation could alleviate disorders associated with lipid metabolism, inflammation, and intestinal mucosal barrier injury. Moreover, levels of serum alanine aminotransferase, gamma‐glutamyl transferase, triglyceride (TG), and hepatic TG were significantly increased in the model group; however, these levels were significantly decreased following the 12‐week L. casei supplementation. In addition, we observed notable improvements in intestinal mucosal barrier function and alterations in T lymphocyte subsets and natural killer cells in L. casei‐treated rats when compared with the model group. Furthermore, L. casei intervention alleviated serum levels of tumor necrosis factor‐α and interleukin‐1β, accompanied by decreased serum endotoxin levels and downregulated expression of toll‐like receptor 4 and its related molecules MyD88, nuclear factor kappa‐B p65, and TNF‐α. Accordingly, supplementation with L. casei could effectively improve liver injury induced by the synergistic interaction between alcohol and iron. The underlying mechanism for this improvement may be related to immune regulation and inhibition of enterogenic endotoxin‐mediated inflammation.
Additive manufacturing applications of phase‐field‐based topology optimization using adaptive isogeometric analysis
Authors: Carraturo Massimo , Hennig Paul , Alaimo Gianluca , Heindel Leonhard , Auricchio Ferdinando , Kästner Markus , Reali Alessandro
Published: August 2021

In this contribution, we apply adaptive isogeometric analysis to a diffuse interface model for topology optimization. First, the influence of refinement and coarsening parameters on the optimization procedure are evaluated and discussed on a two‐dimensional problem and a possible workflow to convert smooth isogeometric solutions into 3D printed products is described. Second, to assess the required numerical accuracy of the proposed simulation framework, numerical results obtained adopting different stopping criteria are experimentally evaluated for a three‐dimensional benchmark problem.
Geochronology and tectonic significance of A‐type granite from Misho, NW Iran: Implications for the detachment of Cimmeria from Gondwana and the opening of Neo‐Tethys
Authors: Jamei Susan , Ghorbani Mansour , Jafari Amin , Williams Ian S. , Moayyed Mohsen
Published: August 2021

The Cimmerian Terrane, part of which forms the Central Iranian Plateau, is one of several continental fragments produced during the early‐ to mid‐Palaeozoic breakup of the northern margin of Gondwana. Magmatic evidence for the final separation of the Terrane from Gondwana and formation of the intervening Neo‐Tethys Ocean is preserved in the Misho Mountains SW of Marand, NW Iran. A small (30 km2) body of subalkaline granite intruding Precambrian sedimentary rocks of the Kahar Formation has numerous chemical features that identify it as an A‐type granite, including high Ga/Al, K2O + Na2O, FeOt/(FeOt + MgO) and incompatible elements (LILE and HFSE), and low CaO and P2O5. Such features are consistent with the asthenospheric upwelling above a rising mantle plume. Zircon ages of 350.8 ± 3.0, 345.4 ± 3.2, and 343.6 ± 4.0 Ma measured on three samples of the Misho A‐type granite along with the same granites exposed in the western domain (Herris area, 306 Ma) reveal that the crystallization process occurred sequentially in different stages. The obtained ages record detachment of the Cimmerian Terrane from Gondwana and the initiation of Neo‐Tethys at least in the Early Carboniferous, significantly earlier than previous researchers have proposed.
The barriers and enablers to implementing the New South Wales Healthy School Canteen Strategy in secondary schools in the Illawarra and Shoalhaven regions – A qualitative study
Authors: Johnston Rosi , Norman Jennifer , Furber Susan , Parkinson Julie
Published: August 2021

Issue addressed

In 2017, the New South Wales Healthy School Canteen Strategy (Strategy) was introduced into primary and secondary schools. Studies have reported that secondary schools have a lower level of compliance with healthy canteen policies compared with primary schools. This study aims to identify and describe the barriers and enablers to implementing the Strategy in Department of Education (DoE) secondary schools in the Illawarra and Shoalhaven regions.

Methods

The framework underpinning the study was the systems theory. Canteen managers (CM) and principals from the 21 DoE secondary schools in the Illawarra and Shoalhaven regions were invited to participate in semi‐structured interviews. The interviews were structured around the five focus areas of the Strategy, including questions on school nutrition policies and the role of the canteen. Data were collated using the interview guides as a framework and qualitative content analysis, using manual coding, was undertaken.

Results

Eight (38%) schools participated with seven CMs and six principals interviewed. Barriers to implementing the Strategy included the changing role of the canteen, the increased demands placed on CMs and inconsistencies between the school food environment and the Strategy. Enablers included monitoring implementation, and internal and external support. This study also recognised that previously identified barriers to healthy canteen strategy implementation are ongoing.

Conclusions

The school canteen is an integral part of the school environment and therefore needs whole‐of‐school support if successful implementation of the Strategy is to occur.

So what

Addressing the barriers and promoting the enablers identified in this study will support better nutrition policy implementation in secondary schools.
Early‐term deliveries and long‐term pediatric ophthalmic morbidity of the offspring#
Authors: Ben‐Shmuel Atar , Sheiner Eyal , Tsumi Erez , Wainstock Tamar , Feinblum Dvora , Walfisch Asnat
Published: August 2021

Objective

To examine whether early‐term delivery impacts on the long‐term ophthalmic health of offspring.

Methods

A retrospective population‐based cohort study was conducted, including all singleton deliveries (1991–2014) occurring at a tertiary medical center. Gestational age was divided into: early prematurity, late prematurity, and early, full, late, and post term. Hospitalizations of offspring up to 18 years of age involving ophthalmic morbidity were evaluated. Survival curves compared cumulative hospitalizations and regression models controlled for confounders.

Results

During the study period, 243 363 deliveries met the inclusion criteria. Ophthalmic‐related hospitalization rates were lower among early‐term born children (1.0%) as compared with early‐ (2.2%) and late‐preterm (1.3%) born children, but higher than those in full‐ (0.9%), late‐ (0.8%), and post‐term (0.8%) born offspring (P < 0.001). The survival curve demonstrated significantly different hospitalization rates in the different gestational ages (P < 0.001). The regression demonstrated an independent risk for ophthalmic morbidity among early‐term born offspring (adjusted hazard ratio 1.14, confidence interval 1.03–1.27, P = 0.009), whereas late‐ and post‐term deliveries were associated with a lower risk (adjusted hazard ratio 0.83 and 0.74, respectively) as compared with full‐term deliveries.

Conclusion

The risk for long‐term ophthalmic‐related hospitalizations of offspring gradually declines as gestational age advances.
Prenatal detection of placenta previa and placenta accreta spectrum: Evaluation of the routine mid‐pregnancy obstetric ultrasound screening between 2013 and 2017
Authors: Svanvik Teresia , Jacobsson Anna‐Karin , Carlsson Ylva
Published: August 2021

Objective

To examine the detection rate of placenta previa and placenta accreta spectrum (PAS) by routine mid‐pregnancy obstetric ultrasound and to estimate risk factors and prevalence within this cohort.

Methods

This was an observational cohort study with prospectively collected data. Women attending routine mid‐pregnancy obstetric ultrasound at the Sahlgrenska University Hospital with a suspected cup‐shaped placenta (cohort 1, n = 339) and women diagnosed with placenta previa or PAS (cohort 2, n = 227) were analyzed according to detection rate, risk factors, and prevalence.

Results

The detection rates of placenta previa and PAS were 49% (98) and 25% (14), respectively. However, 216 (99%) women with placenta previa were diagnosed prenatally, as were 14 (50%) women with PAS. In vitro fertilization was identified as the strongest independent risk factor for placenta previa (odds ratio 6.96; 95% confidence interval 4.77–10.16, P < 0.001). Risk factors were present for all women with PAS. The prevalence of placenta previa was 44/10 000 deliveries, and for PAS, 5.6/10 000 deliveries.

Conclusion

The existing routine mid‐pregnancy obstetric ultrasound screening showed low detection rate for placenta previa and PAS. Adding risk factors could improve the detection rate.
Sulfur‐containing compounds as electrolyte additives for lithium‐ion batteries
Authors: Tong Bo , Song Ziyu , Wan Huihai , Feng Wenfang , Armand Michel , Liu Jincheng , Zhang Heng , Zhou Zhibin
Published: August 2021

Originating from “rocking‐chair concept”, lithium‐ion batteries (LIBs) have become one of the most important electrochemical energy storage technologies, which have largely impacted our daily life. The utilization of electrolyte additives in small quantities (≤5% by wt or vol) has been long viewed as an economical and efficient approach to regulate the properties of electrolyte and electrode–electrolyte interphases and consequently improve the cycling performance of LIBs. Among all the kinds of electrolyte additives, sulfur‐containing compounds have gained significant attention due to their unique features in building stable electrode–electrolyte interphases and protect battery cells from overcharging. In this work, advances and progresses of sulfur‐containing additives used in LIBs are overviewed, with special attention paid to the working mechanisms of these electrolyte additives. Particularly, four representative sulfur‐containing compounds (i.e., 1,3‐propane sultone, prop‐1‐ene‐1,3‐sultone, 1,3,2‐dioxathiolane‐2,2‐dioxide, and ethylene sulfite) are comparatively discussed concerning their impact on electrode–electrolyte interphases and cell performances. Future work on the development of sulfur‐containing compounds as functional electrolyte additives is also provided. The present review is anticipated to be not only a base document to access the status quo in this research domain but also a guideline to select specialized additives and electrolytes for practical applications.

image
Improving cerebral microvascular image quality of optical coherence tomography angiography with deep learning‐based segmentation
Authors: Fan Fan , Zhang Jisheng , Zhu Lianqing , Ma Zongqing , Zhu Jiang
Published: August 2021

Optical coherence tomography angiography (OCTA) can map the microvascular networks of the cerebral cortices with micrometer resolution and millimeter penetration. However, the high scattering of the skull and the strong noise in the deep imaging region will distort the vasculature projections and decrease the OCTA image quality. Here, we proposed a deep learning‐based segmentation method based on a U‐Net convolutional neural network to extract the cortical region from the OCT image. The vascular networks were then visualized by three OCTA algorithms. The image quality of the vasculature projections was assessed by two metrics, including the peak signal‐to‐noise ratio (PSNR) and the contrast‐to‐noise ratio (CNR). The results show the accuracy of the cortical segmentation was 96.07%. The PSNR and CNR values increased significantly in the projections of the selected cortical regions. The OCTA incorporating the deep learning‐based cortical segmentation can efficiently improve the image quality and enhance the vasculature clarity.
Physiologically Based Pharmacokinetic Modeling to Assess the Impact of CYP2D6‐Mediated Drug‐Drug Interactions on Tramadol and O‐Desmethyltramadol Exposures via Allosteric and Competitive Inhibition
Authors: Long Tao , Cristofoletti Rodrigo , Cicali Brian , Michaud Veronique , Dow Pamela , Turgeon Jacques , Schmidt Stephan
Published: August 2021

Tramadol is an opioid medication used to treat moderately severe pain. Cytochrome P450 (CYP) 2D6 inhibition could be important for tramadol, as it decreases the formation of its pharmacologically active metabolite, O‐desmethyltramadol, potentially resulting in increased opioid use and misuse. The objective of this study was to evaluate the impact of allosteric and competitive CYP2D6 inhibition on tramadol and O‐desmethyltramadol pharmacokinetics using quinidine and metoprolol as prototypical perpetrator drugs. A physiologically based pharmacokinetic model for tramadol and O‐desmethyltramadol was developed and verified in PK‐Sim version 8 and linked to respective models of quinidine and metoprolol to evaluate the impact of allosteric and competitive CYP2D6 inhibition on tramadol and O‐desmethyltramadol exposure. Our results show that there is a differentiated impact of CYP2D6 inhibitors on tramadol and O‐desmethyltramadol based on their mechanisms of inhibition. Following allosteric inhibition by a single dose of quinidine, the exposure of both tramadol (51% increase) and O‐desmethyltramadol (52% decrease) was predicted to be significantly altered after concomitant administration of a single dose of tramadol. Following multiple‐dose administration of tramadol and a single‐dose or multiple‐dose administration of quinidine, the inhibitory effect of quinidine was predicted to be long (≈42 hours) and to alter exposure of tramadol and O‐desmethyltramadol by up to 60%, suggesting that coadministration of quinidine and tramadol should be avoided clinically. In comparison, there is no predicted significant impact of metoprolol on tramadol and O‐desmethyltramadol exposure. In fact, tramadol is predicted to act as a CYP2D6 perpetrator and increase metoprolol exposure, which may necessitate the need for dose separation.
Pharmacokinetic/Pharmacodynamic Analysis of Guselkumab for Treatment of Palmoplantar Pustulosis: Clinical Implications of Guselkumab Dose, Disease Severity, and Smoking in Japanese Patients
Authors: Iwaki Yuki , Shibata Sayori , Hu Chuanpu
Published: August 2021

Guselkumab is a human IgG1λ monoclonal antibody that has been approved for treatment of multiple immunologic diseases including palmoplantar pustulosis in Japan. The efficacy of guselkumab in reducing disease severity as compared with placebo has been demonstrated in phase 2 and 3 clinical studies. In some patients assigned to the placebo treatment, worsening of Palmoplantar Pustulosis Area and Severity Index (PPPASI) score was noted. Most of these patients were smokers, raising a possibility of an association of smoking with the disease progression. To understand the clinical implications of guselkumab dose, baseline disease severity, and smoking on the treatment effect and describe the longitudinal relationship between guselkumab exposure and the PPPASI score, a pharmacokinetic/pharmacodynamic modeling analysis was conducted using the pooled data from 1 phase 2 and 1 phase 3 study. Data from 207 Japanese patients (77% women and 60% smokers) with a median PPPASI score of 24.6 were included in the analysis. The observed treatment efficacy (the PPPASI score reduction) appeared to be similar at the current approved dose (100 mg) and the higher dose (200 mg). A greater PPPASI score reduction (in absolute points) is expected in patients with higher baseline PPPASI score (severe disease). However, the higher baseline did not translate to larger magnitude of the change from baseline (in percentage) in the PPPASI score. Incorporating a linear disease progression effect in the model significantly decreased the Nonlinear Mixed Effects Modeling objective function value (P < .001). Smoking status appeared to be related to disease worsening in some patients, but the covariate did not reach statistical significance in the model.
Extracellular vesicles from in vivo liver tissue accelerate recovery of liver necrosis induced by carbon tetrachloride
Authors: Lee Jaemin , Kim Sae Rom , Lee Changjin , Jun Ye In , Bae Seoyoon , Yoon Yae Jin , Kim Oh Youn , Gho Yong Song
Published: August 2021

Extracellular vesicles (EVs) are nano‐sized vesicles composed of proteolipid bilayers carrying various molecular signatures of the cells. As mediators of intercellular communications, EVs have gained great attention as new therapeutic agents in the field of nanomedicine. Therefore, many studies have explored the roles of cell‐derived EVs isolated from cultured hepatocytes or stem cells as inducer of liver proliferation and regeneration under various pathological circumstances. However, study investigating the role of EVs directly isolated from liver tissue has not been performed. Herein, to understand the pathophysiological role and to investigate the therapeutic potential of in vivo liver EVs, we isolated EVs from both normal and carbon tetrachloride (CCl4)‐induced damaged in vivo liver tissues. The in vivo EVs purified from liver tissues display typical features of EVs including spherical morphology, nano‐size, and enrichment of tetraspanins. Interestingly, administration of both normal and damaged liver EVs significantly accelerated the recovery of liver tissue from CCl4‐induced hepatic necrosis. This restorative action was through the induction of hepatocyte growth factor at the site of the injury. These results suggest that not only normal liver EVs but also damaged liver EVs play important pathophysiological roles of maintaining homeostasis after tissue damage. Our study, therefore, provides new insight into potentially developing in vivo EV‐based therapeutics for preventing and treating liver diseases.
Leader interpersonal emotion regulation motives, group leader–member exchange, and leader effectiveness in work groups
Authors: Vasquez Cristian A. , Madrid Hector P. , Niven Karen
Published: August 2021

Recent research has shown that leader interpersonal emotion regulation is a relevant process for fostering desirable work outcomes. Expanding knowledge on this stream of research, here we argue that to have a complete view of the influence of leader interpersonal emotion regulation, the motives underlying the regulation behavior, namely, egocentric or prosocial, should also be taken into account. We draw on the informational function of interpersonal emotion regulation motives and use a multisource survey study with 99 group leaders and their 1482 group members to examine the effects of leader interpersonal emotion regulation motives. We found evidence that leader egocentric interpersonal emotion regulation motives were negatively related to group members' perceptions of the relationship quality with their leaders, expressed in the group's mean leader–member exchange (LMX), and, thereby, related to lower leader appraisals of their own effectiveness. However, these negative effects were mitigated when leaders were at the same time prosocially motivated to regulate the emotions of the members of their groups. Therefore, this study contributes to expanding theory on interpersonal emotion regulation and its application to leadership, which is informative for theory and interventions about leaders' affective influence in organizations.
Possible impacts of anomalous Arctic sea ice melting on summer atmosphere
Authors: Wu Bingyi , Li Zhenkun
Published: August 2021

Arctic sea ice melting and its possible impacts on climate variability and extreme weather events in the mid‐latitudes have been of wide concern over the past two decades. Compared with the impacts of sea ice melting on winter, its impacts on summer atmospheric circulation variability and extreme weather events have received less attention, and it is not clear whether the rapid sea ice melting can affect summer temperature and precipitation in the mid‐latitudes. Through observational analyses and simulation experiments forced by observed Arctic sea ice concentration, this study investigates possible impacts of anomalous summer sea ice melting on air temperature, frequency of heatwaves, precipitation, and East Asian summer monsoon variability. It is found that the enhanced summer sea ice melting has occurred since 2007 and dynamically corresponded to the positive phase of the summer Arctic dipole anomaly. Simulation experiments showed that the ensemble means of anomalous summer sea ice melting cases significantly increase surface air temperatures (SATs) and frequencies of heatwaves in the mid‐ and high‐latitudes of both Asia and North America, and decreases SATs in Europe and parts of the Asian continent. Anomalous summer sea ice melting increases summer precipitation in the circumpolar region, mid‐latitudes of East Asia, and the Northwestern Pacific and significantly decreases precipitation in mid‐ and low‐latitudes of North America. In addition, anomalous sea ice melting in simulations deepens the thermal depression in East Asia and strengthens East Asian summer monsoon and its variability. These model results suggest that anomalous sea ice melting may exacerbate impacts of global warming on summer atmosphere over Asia and North America though its impact may not be dominant due to atmospheric internal variability and impacts of other factors.
Changes in the spatial–temporal characteristics of daily snowfall events over the Eurasian continent from 1980 to 2019
Authors: Lin Wenqing , Chen Huopo
Published: August 2021

The observed spatial–temporal variations in daily snowfall over the Eurasian continent from 1980 to 2019 are explored in this study. The results show that the snowfall amount and its number of days are mainly centred in the high latitudes and high terrain regions of the Eurasian continent (such as North Asia), while they are relatively small in Southern Europe, Central Asia and East Asia. During the past decades, a decreasing trend can be observed for snowfall amounts and the numbers of days over most regions of Eurasia, while increases are clear in terms of the mean intensity. In response to climate warming in recent decades, the first date of snowfall occurrence postponed and the ending date advanced across the Eurasian continent. Furthermore, the change characteristics of the different grades of snowfall are also investigated across this region, including light snowfall, moderate snowfall, heavy snowfall and snowstorm. The light snowfall and number of days show a decreasing tendency, which mainly results in a decrease in the total snowfall amount and number of days. However, the amounts of heavy snowfall and snowstorms and their numbers of days are significantly increased, implying that the Eurasian continent has experienced increased severe snowfall events during recent decades.
An application of multiple‐point statistics downscaling approach over North‐West Himalayas in avalanche‐prone areas
Authors: Singhal Akshay , Jha Sanjeev K.
Published: August 2021

Weather data at fine spatial resolution in the Himalayan region are important for assessing various hydrological events such as avalanches. In recent years, national agencies have been exploring the use of Weather Research and Forecasting (WRF) model in this region. Setting up a WRF model with fine spatial grids in the Himalayan region is challenging due to large topographical variations and associated computational cost. In this study, we use High Asia Refined analysis (HAR) dataset to set up a Multiple‐Point Statistics (MPS) based downscaling approach using the hindcast data of years 2001–2012 at both coarse and fine spatial grids. A total of 11 covariates are used in the study belonging to various environmental factors such as weather, location, topography and vegetation. We generate multiple realizations of precipitation and temperature for the year 2013. The efficacy of the MPS model is tested in a gridbox consisting of 61 × 61 grids, in 10 districts and at sites prone to avalanches and extreme precipitation events. Results show that the downscaled precipitation and temperature have reasonable accuracy. Mean monthly root mean square error and mean absolute error values for precipitation range between 2.87–8.0 mm and 1.45–3.27 mm, respectively. For temperature, both the error statistics range between 0.65–1.13 K and 0.51–0.83 K, respectively. Overall, the study shows that MPS is an effective tool for generating reliable fine‐resolution weather information over multiple geographical locations, overcoming the diverse challenges of the Northwest Himalayas. Furthermore, it is capable of providing consistent fine‐resolution weather data at point locations. Such data may be highly sensitive for hydrological studies, such as avalanche forecasting in the Himalayas.
Validation of the scored Patient‐Generated Subjective Global Assessment Short Form as a prognostic tool for incurable cancer patients
Authors: Cunha Marcela Souza , Wiegert Emanuelly Varea Maria , Calixto‐Lima Larissa , de Oliveira Livia Costa
Published: August 2021

Background

The Patient‐Generated Subjective Global Assessment Short Form (PG‐SGA SF) is a standardized tool for assessing nutrition risk in patients with cancer. The aim of this study was to propose and validate a cutoff point for the PG‐SGA SF related to the prognosis of patients with incurable cancer in exclusive palliative care.

Methods

This is a prospective cohort study of patients with incurable cancer at the National Cancer Institute in Brazil. A total sample (n = 2,144) was randomly divided into groups: (1) training (n = 1,072), to determine the most accurate PG‐SGA SF cutoff, and (2) validation (n = 1,072), to test the predictive accuracy of this cutoff point. The receiver operating characteristic curve was plotted to determine the best cutoff point of the PG‐SGA SF related to death. Concordance statistics (C statistic) were used to test the predictive accuracy of the models. Kaplan‐Meier curve and the Cox hazard model were used to verify a prognostic value of the cutoff point.

Results

PG‐SGA SF score ≥15 was found to be the best cutoff based on 90‐day mortality with good accuracy discrimination (C statistic ≥ 0.74). Patients whose PG‐SGA SF score was ≥15 had a shorter survival of 32 (interquartile range [IQR], 12–75) vs 83 days (IQR, 31–90) (p‐value < .001) and higher risk of death (hazard ratio: 2.20; 95% CI, 1.64–2.95).

Conclusions

The proposed PG‐SGA SF cutoff score is valid and, alongside its usefulness in nutrition triage, could provide prognostic value for patients with incurable cancer.
The use of Raman and infrared spectroscopy in determining the space symmetry group among the groups with the same rules of systematic absence in the diffraction patterns: Some basic principles and applications
Authors: Moroz Tatyana N. , Edwards Howell G. M.
Published: August 2021

Raman spectroscopy and infrared (IR) spectroscopy can be used in the determination of the structural organization of crystals from the short‐range order (IR) to the mid‐ and far‐range orders (Raman). Among the 230 possible crystal space groups, only 61 can unambiguously be determined by X‐ray diffraction. In other cases, from two to five space groups are characterized by unified diffraction extinction rules. The symmetry of the active irreducible representations of vibrations in IR, Raman, and hyper‐Raman (HR) spectra for all crystallographic systems are systematized, and cases are indicated where the ambiguity in the assignment of crystal structures to the space groups with unified diffraction extinction rules can be overcome. The refinement of a space group of a mineral by analyzing the selection rules from IR and Raman spectra is discussed, and some examples are considered, including nontronite, kladnoite, and ugrandite.
Accurate intensity calibration of multichannel spectrometers using Raman intensity ratios
Authors: Raj Ankit , Kato Chihiro , Witek Henryk A. , Hamaguchi Hiro‐o
Published: August 2021

We present a general multistep procedure for the determination of wavelength/wavenumber‐dependent sensitivity of Raman spectrometers equipped with multichannel detectors. In this approach, we start with photons‐per‐wavenumber conversion (C0) followed by a correction (C1) for the channel‐to‐channel variation in the sensitivity. The final correction (C2) is determined from a set of observed intensity ratios for standard Raman bands of selected molecules, compared with the analogous reference set of their accurate theoretical counterparts. The developed approach is employed here for calibrating our Raman spectrometer in the high‐wavenumber region using the vibration–rotation Raman bands of H2, HD, and D2. Theoretical intensity ratios for these bands were computed using accurate ro–vibrational matrix elements of polarizability invariants. The presented scheme allowed us to significantly improve the accuracy of the relative Raman intensities for measured samples. The accuracy was examined by determining the Boltzmann temperatures from the Raman intensities and comparing them with the corresponding thermocouple measurements. The uncertainty of such a Raman thermometer was found to be within 5%, confirming the validity and robustness of the proposed intensity calibration scheme. The presented intensity correction goes beyond the scope of common calibration schemes, traditionally limited to emission standards like tungsten lamps. While the first two steps of our calibration process (C0 and C1) are fairly typical, the additional correction (C2) derived from Raman spectral intensities seems to constitute an important novel step towards the standardization of Raman spectroscopy.
Aqueous solution thickening of amino acid‐based surfactant by alkylpyrrolidone
Authors: Liu Xuemin , Wu Ke , Song Weili , Lei Qiuyun , Zhang Hui , Pan Jiajia , Ge Xin
Published: August 2021

The thickening behaviors in aqueous solution of mixed surfactant mixtures containing an amino acid‐based surfactant, sodium lauroyl sarcosinate (SLSar), and a nonionic surfactant, N‐dodecylpyrrolidone (C12P) were investigated using the rheological methods of steady‐shear and frequency sweep. The results varying the added C12P concentration and the mass ratio of SLSar and C12P indicate that the addition of C12P can promote the formation of wormlike micelles and hydrogels, resulting in viscosity enhancement in the mixed aqueous solution of SLSar and C12P. Viscosity maxima in SLSar/water/C12P systems are sensitive to pH, temperature, the concentration of added C12P, and the mass ratio of SLSar and C12P. In the high concentration of total surfactant (30–39 wt%), the enhancement of viscosity obviously occurs by adding 6 wt% C12P, whereas in the low concentration of total surfactant (15 wt%), the C12P must be added more than 9 wt% in 15 wt% mixtures of SLSar and C12P. Moreover, during the solution pH lowered from SLSar' natural pH of 7.2 to the mixture's pKa 5.2, the intermolecular forces between SLSar acid, SLSar anionic salt, and C12P gradually reduce the overall headgroups areas and contribute to the formation of wormlike micelles, hydrogels, and the thickening behaviors.
Design and analysis of depth cues on depth perception in interactive mixed reality simulation systems
Authors: Li Hengwei , Wang Wei , Ma Weiwei , Zhang Gangsheng , Wang Qingli , Qu Jue
Published: August 2021

Implementing an interactive mixed reality simulation system is an economical and risk‐free method for skill training. However, research to enhance the accuracy of mixed reality simulation has always been a challenge. One of the key indicators of a simulation's accuracy is the user's depth perception. Adding depth cues to the simulation scene can effectively increase the accuracy of depth perception. Therefore, in this study, we designed five depth cues to find the one most beneficial for depth perception: (1) depth bar, (2) location ball, (3) fixed window, (4) 3D wireframe, and (5) movable silhouettes. These depth cues were tested using an experimental system with two sets of experimental settings. The first experiment compared the five depth cues at five different viewing distances and showed that the movable silhouettes benefited depth perception accuracy the most. The second experiment compared depth perception accuracies among three different horizontal tilt settings, showing that depth perception accuracy is dependent on the horizontal tilt. Furthermore, different depth perception accuracies were obtained with and without depth cues, proving that the effects from the horizontal tilts were independent of depth cues. The results of these studies provide references for designing interactive mixed reality simulation systems.
What is the likelihood of nonpulmonary metastasis occurring in the absence of lung metastasis in bone and soft tissue sarcoma? A nested case‐control from a sarcoma referral centre
Authors: Hasan Obada , Nasir Momin , Jessar Muneeba , Hashimi Mustafa , An Qiang , Miller Benjamin J.
Published: August 2021

Background and Objectives

Nonpulmonary metastases (NPM) are rare, associated with a poorer prognosis, and maybe missed on conventional chest imaging for sarcoma surveillance. We determined (1) the proportion of NPM occurring in isolation or with synchronous or prior pulmonary metastases (PM), and (2) if initial NPM would have been recognized with a standard surveillance protocol.

Methods

Investigators identified patients who developed initial NPM without prior evidence of or concurrent PM from an ongoing cohort of bone and soft tissue sarcoma (STS) patients. Logistic regression at univariate level was done.

Results

There were 138/630 (22%) patients with metastasis and 66 (10%) had NPM: 50 (8%) patients had PM presenting first, while 16 (3%) had initial NPM. Malignant peripheral nerve sheath tumor, angiosarcoma, rhabdomyosarcoma, synovial sarcoma, and myxoid liposarcoma were six times more likely to develop initial NPM than other subtypes of STS with odds ratio = 6 (95% confidence interval: 1.93–18.65, p value < 0.01). Chest imaging and physical examination were sufficient to identify NPM in all except three bone sarcoma patients.

Conclusions

Patients who develop initial NPM are rare and demonstrate a predilection towards some subtypes of extremity sarcoma. They develop oligometastatic disease, which may be amenable for surgical excision. All isolated or initial NPM in STS patients were discovered by physical examination and standard chest imaging.