bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new transformerless semi‐quadratic buck–boost converter based on combination of Cuk and traditional buck–boost converters
Authors: Hosseinpour Majid , Ahmadi Mahsa , Seifi Ali , Mousavi‐Aghdam Seyed Reza 
Published: July 2022

AbstractIn this paper, a new transformerless buck–boost converter is proposed. This converter is based on combining two basic converters, including Cuk and traditional buck–boost converters, along with a voltage multiplier (VM) at the output side. The proposed semi‐quadratic buck–boost converter operates in continuous conduction mode (CCM) and provides two operation modes by turning the switches on and off. This converter has some merits such as a wide conversion ratio and continuous input current. The proposed converter consists of two switches with simultaneous operation resulting in simplicity in control. A modular configuration and a wide range of duty cycles are available through the proposed converter, which causes higher or lower output voltage and facilitates the converter maintenance. The calculations of the ideal and the real voltage gain, voltage stress of switches and diodes, efficiency, and design consideration of elements are given in this paper. Finally, a prototype is implemented, and experimental waveforms are obtained to prove and validate the simulation results as well as the theoretical analysis of the proposed converter.
Treg cell abnormality and its potential treatments in patients with primary immune thrombocytopenia
Authors: Ji Lili , Cheng Yunfeng 
Published: July 2022

AbstractPrimary immune thrombocytopenia (ITP) is an autoimmune heterogeneous disorder. T regulatory cells (Treg), play an important role in the pathogenesis of the disease. Numerical and functional disorders of Treg cells were both demonstrated in ITP. Thymocyte output decrease and instability of Treg cells contributed to the lower count of the cells. Several immune deregulatory defects of Treg cells further led to the disease's onset. Restoring Treg cells might have a therapeutic effect on ITP. New options focusing on increasing the number, or enhancing the immunomodulating function of Treg cells was reviewed in this manuscript.
Predicting changes in molluscan spatial distributions in mangrove forests in response to sea level rise
Authors: Ma Wei , Wang Mao , Fu Haifeng , Tang Chaoyi , Wang Wenqing 
Published: July 2022

AbstractMollusks are an important component of the mangrove ecosystem, and the vertical distributions of molluscan species in this ecosystem are primarily dictated by tidal inundation. Thus, sea level rise (SLR) may have profound effects on mangrove mollusk communities. Here, we used dynamic empirical models, based on measurements of surface elevation change, sediment accretion, and molluscan zonation patterns, to predict changes in molluscan spatial distributions in response to different sea level rise rates in the mangrove forests of Zhenzhu Bay (Guangxi, China). The change in surface elevation was 4.76–9.61 mm year−1 during the study period (2016–2020), and the magnitude of surface‐elevation change decreased exponentially as original surface elevation increased. Based on our model results, we predicted that mangrove mollusks might successfully adapt to a low rate of SLR (2.00–4.57 mm year−1) by 2100, with mollusks moving seaward and those in the lower intertidal zones expanding into newly available zones. However, as SLR rate increased (4.57–8.14 mm year−1), our models predicted that surface elevations would decrease beginning in the high intertidal zones and gradually spread to the low intertidal zones. Finally, at high rates of SLR (8.14–16.00 mm year−1), surface elevations were predicted to decrease across the elevation gradient, with mollusks moving landward and species in higher intertidal zones blocked by landward barriers. Tidal inundation and the consequent increases in interspecific competition and predation pressure were predicted to threaten the survival of many molluscan groups in higher intertidal zones, especially arboreal and infaunal mollusks at the landward edge of the mangroves, resulting in a substantial reduction in the abundance of original species on the landward edge. Thus, future efforts to conserve mangrove floral and faunal diversity should prioritize species restricted to landward mangrove areas and protect potential species habitats.
Grassland type and seasonal effects have a bigger influence on plant functional and taxonomical diversity than prairie dog disturbances in semiarid grasslands
Authors: Rodriguez‐Barrera Maria Gabriela , Kühn Ingolf , Estrada‐Castillón Eduardo , Cord Anna F. 
Published: July 2022

Abstract

Prairie dogs (Cynomys sp.) are considered keystone species and ecosystem engineers for their grazing and burrowing activities (summarized here as disturbances). As climate changes and its variability increases, the mechanisms underlying organisms' interactions with their habitat will likely shift. Understanding the mediating role of prairie dog disturbance on vegetation structure, and its interaction with environmental conditions through time, will increase knowledge on the risks and vulnerability of grasslands.

Here, we compared how plant taxonomical diversity, functional diversity metrics, and community‐weighted trait means (CWM) respond to prairie dog C. mexicanus disturbance across grassland types and seasons (dry and wet) in a priority conservation semiarid grassland of Northeast Mexico.

Our findings suggest that functional metrics and CWM analyses responded to interactions between prairie dog disturbance, grassland type and season, whilst species diversity and cover measures were less sensitive to the role of prairie dog disturbance. We found weak evidence that prairie dog disturbance has a negative effect on vegetation structure, except for minimal effects on C4 and graminoid cover, but which depended mainly on season. Grassland type and season explained most of the effects on plant functional and taxonomic diversity as well as CWM traits. Furthermore, we found that leaf area as well as forb and annual cover increased during the wet season, independent of prairie dog disturbance.

Our results provide evidence that grassland type and season have a stronger effect than prairie dog disturbance on the vegetation of this short‐grass, water‐restricted grassland ecosystem. We argue that focusing solely on disturbance and grazing effects is misleading, and attention is needed on the relationships between vegetation and environmental conditions which will be critical to understand semiarid grassland dynamics under future climate change conditions in the region.
Distribution and population structure of the smooth‐hound shark, Mustelus mustelus (Linnaeus, 1758), across an oceanic archipelago: Combining several data sources to promote conservation
Authors: Espino Fernando , González José Antonio , Bosch Néstor E. , Otero‐Ferrer Francisco J. , Haroun Ricardo , Tuya Fernando 
Published: July 2022

AbstractSharks play a key role in the structure and functioning of marine ecosystems. More ecological information is essential to implement responsible management and conservation actions on this fauna, particularly at a regional level for threatened species. Mustelus mustelus is widely found in the eastern Atlantic Ocean and catalogued as “Vulnerable” by the IUCN European assessment. In this study, data on the distribution and population structure of this species across the islands of the Canarian archipelago, located along an east to west gradient in the north‐eastern Atlantic, were collected by taking advantage of “Local Ecological Knowledge,” in terms of sightings in coastal waters and long‐term imprints on the local gastronomic heritage, and decadal fisheries landings. Both sources of quantitative data (sightings and fisheries landings) demonstrated that adults of M. mustelus has a significantly larger presence in the eastern and central, than in the western islands of the archipelago. This is also reflected on local gastronomic legacies, with a larger number of recipes in the eastern and central islands. Adult smooth‐hound sharks were significantly more observed in sandy and sandy‐rocky bottoms, with individuals seen throughout the entire year, whereas juveniles aggregate on very shallow waters in spring and summer. Such aggregations require a special management strategy, as they play a key role in critical life stages; these sites should be protected from human perturbations. We also suggest a temporal fishing ban between April and October, when individuals tend to concentrate on nearshore waters. Because of the large differences in presence of this shark among the Canary Islands, management of the species should be adapted to the specific peculiarities of each island, rather than adopting a management policy at the entire archipelago‐scale. Overall, this study sets the basis for further investigation to promote conservation of this vulnerable shark in the study region.
Laying low: Rugged lowland rainforest preferred by feral cats in the Australian Wet Tropics
Authors: Bruce Tom , Williams Stephen E. , Amin Rajan , L'Hotellier Felicity , Hirsch Ben T. 
Published: July 2022

AbstractInvasive mesopredators are responsible for the decline of many species of native mammals worldwide. Feral cats have been causally linked to multiple extinctions of Australian mammals since European colonization. While feral cats are found throughout Australia, most research has been undertaken in arid habitats, thus there is a limited understanding of feral cat distribution, abundance, and ecology in Australian tropical rainforests. We carried out camera‐trapping surveys at 108 locations across seven study sites, spanning 200 km in the Australian Wet Tropics. Single‐species occupancy analysis was implemented to investigate how environmental factors influence feral cat distribution. Feral cats were detected at a rate of 5.09 photographs/100 days, 11 times higher than previously recorded in the Australian Wet Tropics. The main environmental factors influencing feral cat occupancy were a positive association with terrain ruggedness, a negative association with elevation, and a higher affinity for rainforest than eucalypt forest. These findings were consistent with other studies on feral cat ecology but differed from similar surveys in Australia. Increasingly harsh and consistently wet weather conditions at higher elevations, and improved shelter in topographically complex habitats may drive cat preference for lowland rainforest. Feral cats were positively associated with roads, supporting the theory that roads facilitate access and colonization of feral cats within more remote parts of the rainforest. Higher elevation rainforests with no roads could act as refugia for native prey species within the critical weight range. Regular monitoring of existing roads should be implemented to monitor feral cats, and new linear infrastructure should be limited to prevent encroachment into these areas. This is pertinent as climate change modeling suggests that habitats at higher elevations will become similar to lower elevations, potentially making the environment more suitable for feral cat populations.
Solar radiation and soil moisture drive tropical forest understory responses to experimental and natural hurricanes
Authors: Hogan J. Aaron , Sharpe Joanne M. , Van Beusekom Ashley , Stankavich Sarah , Matta Carmona Samuel , Bithorn John E. , Torres‐Díaz Jamarys , González Grizelle , Zimmerman Jess K. , Shiels Aaron B. 
Published: July 2022

AbstractTropical forest understory regeneration occurs rapidly after disturbance with compositional trajectories that depend on species availability and environmental conditions. To predict future tropical forest regeneration dynamics, we need a deeper understanding of how pulse disturbance events, like hurricanes, interact with environmental variability to affect understory demography and composition. We examined fern and sapling mortality, recruitment, and community composition in relation to solar radiation and soil moisture using 17 years of forest dynamics data (2003–2019) from the Canopy Trimming Experiment in the Luquillo Experimental Forest, Puerto Rico. Solar radiation increased 150% and soil moisture increased 40% following canopy trimming of experimental plots relative to control plots. All plots were disturbed in 2017 by Hurricanes Irma and Maria, so experimentally trimmed plots presented the opportunity to study the effects of multiple hurricanes, while control plots isolated the effects of a single natural hurricane. Recruitment rates maximized at 0.14 individuals/plot/month for ferns and 0.20 stems/plot/month for saplings. Recruitment and mortality were distributed more evenly over the 17 years of monitoring in experimentally trimmed plots than in control plots; however, following Hurricane Maria demographic rates substantially increased in control plots only. In experimentally trimmed plots, the largest community compositional shifts occurred as a result of the trimming events, and compositional changes were greatest for control plots after Hurricane Maria in 2017. Pioneer tree and fern species increased in abundance in response to both simulated and natural hurricanes. Following Hurricane Maria, two dominant pioneer species, Cyathea arborea and Cecropia schreberiana, recruited abundantly, but only in control plots. In trimmed plots, increased solar radiation and soil moisture shifted understory species composition steadily toward pioneer and secondary‐successional species, with soil moisture interacting strongly with canopy trimming. Thus, both solar radiation and soil moisture are environmental drivers affecting pioneer species recruitment following disturbance, which interact with canopy opening following hurricanes. Our results suggest that if hurricane disturbances increase in frequency and severity, as suggested by climate change predictions, the understory regeneration of late‐successional species, such as Manilkara bidentata and Sloanea berteroana, which prefer deeper shade and slightly drier soil microsites, may become imperiled.
Sedimentary DNA records long‐term changes in a lake bacterial community in response to varying nutrient availability
Authors: Thorpe Amy C. , Anderson Amy , Goodall Tim , Thackeray Stephen J. , Maberly Stephen C. , Bendle James A. , Gweon Hyun S. , Read Daniel S. 
Published: July 2022

AbstractMicrobial communities play important roles in lake ecosystems and are sensitive to environmental change. However, our understanding of their responses to long‐term change such as eutrophication is limited, as long‐term lake monitoring is rare, and traditional paleolimnological techniques (pigments and microfossils) are restricted to a low taxonomic resolution, or organisms with well‐preserved structures. Sedimentary DNA (sedDNA) is a promising technique to reconstruct past microbial communities in sediments, but taphonomic processes and the ability of sedDNA to record bacterial pelagic history accurately are largely unknown. Here, we sequenced the 16S rRNA gene in triplicate sediment cores from Esthwaite Water (English Lake District) which has concurrent long‐term monitoring and observational data. The sediment record spanned 113 years and included an episode of increased nutrient availability from the 1970s, followed by a more recent decline. Trends in bacterial community composition were broadly similar among the three sediment cores. Cyanobacterial richness in the sediment cores correlated significantly with that of cyanobacteria in a 65‐year microscopy‐based monitoring record, and some known pelagic bacterial taxa were detected in the sediment. sedDNA revealed distinct shifts in community composition in response to changing lake physicochemical conditions. The relative abundance of cyanobacteria closely reflected nutrient enrichment, and Proteobacteria, Bacteroidetes, and Verrucomicrobia were relatively more abundant in recent sediments, while Chloroflexi, Firmicutes, Acidobacteria, Nitrospirae, Spirochaetes, and Planctomycetes declined in more recent sediments. Following lake restoration efforts to reduce nutrient enrichment, the relative abundance of cyanobacteria returned to pre‐1970 levels, but the bacterial community did not fully recover from the period of intense eutrophication within the time scale of our study. These results suggest that sedDNA is a valuable approach to reconstruct lake microbial community composition over the 100‐year time scale studied, but an improved understanding of DNA deposition and degradation is required to further the application of sedDNA in paleolimnology.
Use of liver stiffness measurements in acute decompensated heart failure: new applications of a non‐invasive technique
Authors: Dhillon Jaspreet K. , Fong Michael W. , Fong Tse‐Ling 
Published: July 2022

AbstractHeart failure (HF) is a complex disease associated with multisystem organ failure, recurrent hospital admissions, and increased mortality. Acute decompensated heart failure (ADHF) increases central venous pressure (CVP) with resultant hepatic congestion, and this relationship has prognostic significance. The gold standard method of measuring CVP, right heart catheterization, is invasive and costly, prompting further investigation into more accurate non‐invasive assessments in HF patients, including liver elastography. Liver elastography relies on imaging techniques to assess liver stiffness measurements (LSM), with high values equating to increased stiffness. While this was developed to assess fibrosis in liver disease, LSM also reflect increased CVP and hepatic congestion. Multiple studies involving ADHF patients, find that increased LSM are independently predictive of increased cardiac events, all‐cause mortality, and worse post‐operative outcome after both acute HF exacerbation and left ventricular assist device (LVAD) placement. In this review, we discuss the role of LSM as a surrogate for CVP and their applications in determining prognosis in both the ADHF and LVAD populations.
Myocardial strain for heart failure with preserved ejection fraction but without diastolic dysfunction
Authors: Park Jin Joo , Hwang In‐Chang , Kang Si‐Hyuck , Park Jun‐Bean , Park Jae‐Hyeong , Cho Goo‐Yeong 
Published: July 2022

AbstractAimsSome patients with apparent heart failure (HF) have an ejection fraction (EF) ≥ 50% and elevated levels of natriuretic peptides (NPs), but no significant diastolic dysfunction. Among these, some may have HF, others may not. Myocardial strain is an excellent prognostic factor.Methods and resultsAmong 4312 consecutive patients with acute HF from three tertiary hospitals, we included 355 patients with EF of ≥50% and elevated levels of NPs, without significant diastolic dysfunction. Patients were classified as having impaired global longitudinal strain (GLS < 16%) or normal GLS (GLS ≥ 16%). The primary endpoint was 5 year all‐cause mortality. The mean age was 70.3 years and 49% were female. Overall, 107 patients (30.1%) died at 5 years. As per the definition, 176 (49.6%) patients had impaired GLS and 179 (50.4%) had normal GLS. Patients with normal GLS had lower 5 year all‐cause mortality than those with impaired GLS (P < 0.001). When comparing with the 11 365 age‐matched and sex‐matched controls, patients with normal GLS had the same long‐term survival as the controls (P = 0.834), whereas those with impaired GLS had 48% increased risk of all‐cause mortality (hazard ratio, 1.48; 95% confidence interval, 1.17–1.89).ConclusionsAmong patients with apparent HF and preserved EF but without diastolic dysfunction, those with impaired GLS may be considered to have HF.
Metal‐Mediated Interactions in Homo‐ and Heterobimetallic Edifices with Lanthanides: A Study in Solution
Authors: Hamacek Josef , Elhabiri Mourad , Le Guennic Boris , Shanzer Abraham , Albrecht‐Gary Anne‐Marie 
Published: July 2022

AbstractWe report here on the coordination properties of a series of lanthanide cations (Ln=La, Nd, Eu, Tb, Er) with a tripodal homoditopic ligand L, which is bearing three diamido‐dihydroxamate arms anchored on a tertiary amine. The complexes of L with lanthanides were studied in a MeOH/H2O (80/20 by weight) solvent and a marked size‐discriminating effect depending on the intramolecular interactions was observed in the tripodal dinuclear lanthanide edifice. Positive cooperative effects favour the formation of the bimetallic LLn2 complexes compared with the monometallic analogues for the heavier lanthanide cations (Eu, Tb, Er), while the lighter ones (La, Nd) show a decrease of cooperative interactions in the corresponding bimetallic species. Moreover, increased levels of heterobimetallic complexes are detected for Ln(III) pairs containing a lighter Ln(III) ion and a heavier one. In contrast with the adjunctive ligand exchange reported for LFe2 and CDTA, the corresponding substitution reaction for LLn2 occurs according to a disjunctive mechanism. Our work thus highlights the importance of the balance between the rigidity of a tripodal structure and the flexibility of the side arms to accommodate two trivalent cations in a supramolecular ensemble.
Reassignment of Improbable Natural Products Identified through Chemical Principle Screening
Authors: Elyashberg Mikhail , Novitskiy Ivan M. , Bates Roderick W. , Kutateladze Andrei G. , Williams Craig M. 
Published: July 2022

AbstractNatural products continue to be reported at an astonishing rate from a wide range of multidisciplinary research activities in the pursuit of understanding the chemistry of biodiversity. However, the elucidation of chemical structure in the modern era is heavily reliant on the analysis and interpretation of multiple spectroscopic outputs, and in most cases this activity is by no means trivial. Structural errors continue to be described given the inherent complexity of natural products. Computer‐Assisted Structure Elucidation (CASE) continues to provide improved resolving power in this regard, but for enhanced accuracy quantum chemical spectrum prediction methodology is paramount. Reported herein are a range of counterfactual natural products, identified through chemical principal screening, which have been reassigned using a combination of chemical intuition, chemical synthesis, CASE and DU8+ spectrum prediction.
Synthesis of Benzothiazole‐ and Benzoxazole‐2‐carboxamides by 2‐Chloracetamides and 2‐Amino(thio)phenols Cyclocondensation with Elemental Sulfur in Water
Authors: Kozlov Mikhail A. , Bolshakov Konstantin M. , Kolotyrkina Natalia G. , Zavarzin Igor V. 
Published: July 2022

AbstractNew straightforward synthesis of benzothiazole‐2‐carboxamides and benzoxazole‐2‐carboxamides from 2‐chloracetamides, 2‐amino(thio)phenols and elemental sulfur has been developed. Main advantage of this protocol is the utilization of water as reaction media, which lead to simple reaction procedure. Also this process is distinguished by good tolerance toward different functional groups. Yields of products is up to 99 %.