bluuebunny/crossref_metadata_2025_split huggingface dataset:
Germination and seedling growth of Calluna vulgaris is sensitive to regional climate, heathland succession, and drought
Authors: Birkeli Kristine , Gya Ragnhild , Haugum Siri Vatsø , Velle Liv Guri , Vandvik Vigdis 
Published: July 2023

AbstractThe coastal heathlands of Northwest Europe are highly valued cultural landscapes, that are critically endangered due to land use and climatic changes, such as increased frequency and severity of drought events. Our study is the first to assess how the germination and early seedling growth of Calluna vulgaris respond to drought. In a factorial design field experiment, we exposed maternal plants to three in‐situ drought treatments (control, 60%, 90% roof coverage), across three successional stages after fire (pioneer, building, mature), and two regions (60°N, 65°N). Seeds from 540 plants within the experiment were, weighed, and exposed to five water potentials, ranging from −0.25 to −1.7 MPa, in a growth chamber experiment. We recorded germination (percentage, rate), seedling growth (above‐ vs. belowground allocation), and seedling functional traits (specific leaf area [SLA], specific root length [SRL]). Overall variation in germination between regions, successional stages, and maternal drought treatments was largely mediated by variation in seed mass. Plants from the northernmost region had higher seed mass and germination percentages. This is indicative of higher investment in seeds, likely linked to the populations' absence of vegetative root sprouting. Seeds from the mature successional stage germinated to lower final percentages than those from earlier successional stages, especially when the maternal plants had been exposed to drought (60% and 90% roof coverage). Exposure to reduced water availability decreased germination percentage and increased the time to 50% germination. Seedlings fully developed in the range −0.25 to −0.7 MPa, with increased root:shoot and lower SRL during reduced water availability, suggesting a resource‐conservative response to drought during the early stages of development. Our results thus suggest a sensitivity to drought during the germination and seedling life‐history stages that may reduce Calluna's ability to re‐establish from seeds as the incidence and severity of droughts are projected to increase under future climates.
SensorDrop: A system to remotely detach individual sensors from wildlife tracking collars
Authors: Rafiq K. , Appleby R. G. , Davies A. , Abrahms B. 
Published: July 2023

AbstractThe growing diversity of animal‐borne sensor types is revolutionizing our understanding of wildlife biology. For example, researcher‐developed sensors, such as audio and video loggers, are being increasingly attached to wildlife tracking collars to provide insights into a range of topics from species interactions to physiology. However, such devices are often prohibitively power‐intensive, relative to conventional wildlife collar sensors, and their retrieval without compromising long‐term data collection and animal welfare remains a challenge. We present an open‐source system (SensorDrop) for remotely detaching individual sensors from wildlife collars. SensorDrop facilitates the retrieval of power‐intensive sensors while leaving non‐resource‐intensive sensors intact on animals. SensorDrop systems can be made using commercially available components and are a fraction of the cost of other timed drop‐off devices that detach full wildlife tracking collars. From 2021 to 2022, eight SensorDrop units were successfully deployed on free‐ranging African wild dog packs in the Okavango Delta as part of audio‐accelerometer sensor bundles attached to wildlife collars. All SensorDrop units detached after 2–3 weeks and facilitated the collection of audio and accelerometer data while leaving wildlife GPS collars intact to continue collecting locational data (>1 year), critical for long‐term conservation population monitoring in the region. SensorDrop offers a low‐cost method to remotely detach and retrieve individual sensors from wildlife collars. By selectively detaching battery‐depleted sensors, SensorDrop maximizes the amount of data collected per wildlife collar deployment and mitigates ethical concerns on animal rehandling. SensorDrop adds to the growing body of open‐source animal‐borne technologies being utilized by wildlife researchers to innovate and expand upon data collection practices and supports the continued ethical use of novel technologies within wildlife studies.
Inter‐annual variation in amphibian larval interspecies interactions
Authors: Ford Jessica , Green David M. 
Published: July 2023

AbstractThe outcomes of species interactions can vary by life stage, year, and surrounding environmental conditions. Amphibian species are expected to compete most strongly during their tadpole stage when they exist in the highest densities. Changes in arrival timing, surrounding aquatic communities, and yearly conditions could all affect the outcome of larval competition. In Long Point, Ontario, the Fowler's toad (Anaxyrus fowleri) is at the northern edge of its range and overlaps with the more common American toad (Anaxyrus americanus). Both species breed in ponds that encounter high inter‐annual variation. To determine whether these species compete strongly, and if this effect was replicated across multiple years, we raised both species as tadpoles together and, apart, in mesocosms in 2018 and 2021. We measured survivorship to, weight at, and time to metamorphosis for both species in both years. We determined that the presence of American toad tadpoles consistently had a detrimental effect on Fowler's toad tadpoles, even though this effect presented itself differently across years. Our study suggests that competitive exclusion by American toads could be occurring at the edge of the Fowler's toad's range. This study further demonstrates the importance of studying communities across multiple years to understand the full scope of species interactions.
Possible niche compression and individual specialization in Pacific Arctic beluga (Delphinapterus leucas) from the 19th to 20th century
Authors: Fraleigh Devin C. , Archer Frederick I. , Williard Amanda S. , Hückstädt Luis A. , Fleming Alyson H. 
Published: July 2023

AbstractCetaceans have shown a potential to be used as sentinel species for tracking environmental change in marine ecosystems, yet our assessment of change is typically limited to recent decades and lacks ecological baselines. Using historical museum specimens, we compared community niche metrics and degree of individual dietary specialization in groups of Pacific Arctic beluga (Delphinapterus leucas) from the 1800s (n = 5) to 1900s (n = 10) using stable carbon and nitrogen isotopes drilled from teeth. Beluga occupied a broader trophic niche and demonstrated a higher degree of individual specialization in the 1800s than in the 1900s. The cause of this shift is difficult to confirm given long timescales and constraints of specimen‐based research but could indicate changes in the prey base or competition. The scale and nature of this detected shift provide perspective for continued research on these climate‐vulnerable species.
Influence of serum transferrin concentration on diagnostic criteria for iron deficiency in chronic heart failure
Authors: Graham Fraser J. , Pellicori Pierpaolo , Masini Gabriele , Cuthbert Joseph J. , Clark Andrew L. , Cleland John G. F. 
Published: July 2023

AbstractAimsTransferrin saturation (TSAT), a marker of iron deficiency, reflects both serum concentrations of iron (SIC) and transferrin (STC). TSAT is susceptible to changes in each of these biomarkers. Little is known about determinants of STC and its influence on TSAT and mortality in patients with heart failure. Accordingly, we studied the relationship of STC to clinical characteristics, to markers of iron deficiency and inflammation and to mortality in chronic heart failure (CHF).Methods and resultsProspective cohort of patients with CHF attending a clinic serving a large local population. A total of 4422 patients were included (median age 75 (68–82) years; 40% women; 32% with left ventricular ejection fraction ≤40%). STC ≤ 2.3 g/L (lowest quartile) was associated with older age, lower SIC and haemoglobin and higher high‐sensitivity C‐reactive protein, ferritin and N‐terminal pro‐brain natriuretic peptide compared with those with STC > 2.3 g/L. In the lowest STC quartile, 624 (52%) patients had SIC ≤13 μmol/L, of whom 38% had TSAT ≥20%. For patients in the highest STC quartile, TSAT was <20% when SIC was >13 μmol/L in 185 (17%) patients. STC correlated inversely with ferritin (r = −0.52) and high‐sensitivity C‐reactive protein (r = −0.17) and directly with albumin (r = 0.29); all P < 0.001. In models adjusted for age, N‐terminal pro‐brain natriuretic peptide and haemoglobin, both higher SIC (hazard ratio 0.87 [95% CI: 0.81–0.95]) and STC (hazard ratio 0.82 [95% CI: 0.73–0.91]) were associated with lower mortality. SIC was more strongly associated with both anaemia and mortality than either STC or TSAT.ConclusionsMany patients with CHF and a low STC have low SIC even when TSAT is >20% and serum ferritin >100 μg/L; such patients have a high prevalence of anaemia and a poor prognosis and might have iron deficiency but are currently excluded from clinical trials of iron repletion.
Changes in mid‐regional pro‐adrenomedullin during treatment with sacubitril/valsartan
Authors: Myhre Peder L. , Liu Yuxi , Kulac Ian J. , Claggett Brian L. , Prescott Margaret F. , Felker G. Michael , Butler Javed , Piña Ileana L. , Rouleau Jean L. , Zile Michael R. , McMurray John J.V. , Ward Jonathan H. , Solomon Scott D. , Januzzi James L. 
Published: July 2023

ABSTRACTAimsAdrenomedullin is a vasodilatory peptide with a role in microcirculatory and endothelial homeostasis. Adrenomedullin is a substrate for neprilysin and may therefore play a role in beneficial effects of sacubitril/valsartan (Sac/Val) treatment.Methods and resultsMid‐regional pro‐adrenomedullin (MR‐proADM) was measured in 156 patients with heart failure with reduced ejection fraction (HFrEF) treated with Sac/Val and 264 patients with heart failure with preserved ejection fraction (HFpEF) randomized to treatment with Sac/Val or valsartan. Echocardiography and Kansas City Cardiomyopathy Questionnaire results were collected at baseline and after 6 and 12 months in the HFrEF cohort. Median (Q1–Q3) baseline MR‐proADM concentrations were 0.80 (0.59–0.99) nmol/L in HFrEF and 0.88 (0.68–1.20) nmol/L in HFpEF. After 12 weeks of treatment with Sac/Val, MR‐proADM increased by median 49% in HFrEF and 60% in HFpEF, while there were no significant changes in valsartan‐treated patients (median 2%). Greater increases in MR‐proADM were associated with higher Sac/Val doses. Changes in MR‐proADM correlated weakly with changes in N‐terminal pro‐B‐type natriuretic peptide, cardiac troponin T and urinary cyclic guanosine monophosphate. Increases in MR‐proADM were associated with decreases in blood pressure, but not significantly associated with changes in echocardiographic parameters or health status.ConclusionsMR‐proAD concentrations rise substantially following treatment with Sac/Val, in contrast to no change from valsartan. Change in MR‐proADM from neprilysin inhibition did not correlate with improvements in cardiac structure and function or health status. More data are needed regarding the role of adrenomedullin and its related peptides in the treatment of heart failure.Clinical Trial Registration: PROVE‐HF ClinicalTrials.gov Identifier: NCT02887183, PARAMOUNT ClinicalTrials.gov Identifier: NCT00887588.
Ion transport properties in the pH‐dependent bipolar nanochannels
Authors: Liu Tao , He Xiaohan , Zhao Juncheng , Shi Liuyong , Zhou Teng , Wen Liping 
Published: July 2023

AbstractIn recent years, researchers have made significant strides in understanding the ion transport characteristics of nanochannels, resulting in the development of various materials, modifications, and shapes of nano ion channel membranes. The aim is to create a nanochannel membrane with optimal ion transport properties and high stability by adjusting factors, such as channel size, surface charge, and wettability. However, during the nanochannel film fabrication process, controlling the geometric structures of nanochannels can be challenging. Therefore, exploring the stability of nanochannel performance under different geometric structures has become an essential aspect of nanochannel design. This article focuses on the study of cylindrical nanochannel structures, which are categorized based on the different methods for generating bipolar surface charges on the channel's inner surface, either through pH gradient effects or different material types. Through these two approaches, the study designed and analyzed the stability of ion transport characteristics in two nanochannel models under varying geometric structures. Our findings indicate that nanochannels with bipolar properties generated through pH gradients demonstrate more stable ion selection, whereas nanochannels with bipolar properties generated through different materials show stronger stability in ion rectification. This conclusion provides a theoretical foundation for future nanochannel designs.
20(S)‐Protopanaxadiol saponins isolated from Panax notoginseng target caveolin‐1 against intestinal barrier dysfunction by alleviating inflammatory injury and oxidative stress in experimental murine colitis
Authors: Lu Pengde , Chen Jinfen , Chen Ying , Quan Xingping , Liu Jiayue , Han Yan , Li Yiyang , Yang Li , Wan Jian‐Bo , Zhao Yonghua 
Published: July 2023

AbstractUlcerative colitis (UC) is a digestive disease with a high incidence and is difficult to be cured due to its complex etiology. It has evidenced that intestinal barrier dysfunction plays a predominant role in UC. 20(S)‐protopanaxadiol saponins (PDS) isolated from Panax notoginseng possess anti‐inflammatory and antioxidative activities, suggesting its potential of treating UC. Herein, the therapeutic effects of PDS against UC and underlying mechanisms in the aspect of intestinal barrier dysfunction were investigated in vivo and in vitro. The results showed PDS had protective effects against dextran sulfate sodium–induced colitis, including attenuating weight loss, disease activity index score elevation, colon length shortening, and histological lesions. Additionally, PDS reduced the colonic activity of myeloperoxidase and the cytokine levels of TNF‐α, IL‐6, and IL‐1β, decreased MDA production, and elevated colonic activities of SOD and GSH‐Px in the colitis mice. The expressions of proteins related to tight junction (TJ), including ZO‐1, claudin‐5, occludin, caveolin‐1 (Cav‐1), and Nrf2 were downregulated, whereas that of Keap1 was upregulated after colitis induction. These changes were reversed by PDS. Cav‐1 expression was downregulated in lipopolysaccharides (LPS)‐ and H2O2‐induced HCT116 cells, and the expressions of ZO‐1, claudin‐5, and occludin were suppressed in HCT116 cells stimulated by LPS and H2O2 combined with Cav‐1 small interfering RNA transfection, which were ameliorated by PDS, suggesting PDS targeted Cav‐1 against intestinal barrier damage. Collectively, PDS alleviates inflammatory injury and oxidative stress by regulating the Nrf2/Keap1 pathway, contributing to targeting Cav‐1 against intestinal epithelial TJ proteins loss. It suggests PDS might be a promising therapeutic natural product for UC treatment.
Low back pain in a sample of Syrian pregnant women: A cross‐sectional study
Authors: Amayri Alaa , Khalayli Naram , Haj Ali Diaa , Kudsi Maysoun 
Published: July 2023

AbstractIntroductionLow back pain related to pregnancy occurs in 60%–70% of pregnancies, at any time during pregnancy. During pregnancy, many factors such as weight gain, and others are the causes of the back pain. In Syria, due to the circumstances of the war, many pregnant women may be exposed to increase the risk of lower back pain, so this study will determine the prevalence of lower back pain among pregnant women and its potential risk factors. We aimed to evaluate the prevalence of low back pain in pregnant women and to assess the risk factors related to it.MethodsA cross‐sectional, observational study was conducted between May 2020 and December 2022 at Obstetrics and Gynecology University Hospital in Damascus, Syria. Pregnant women aged over 18 years were selected from the outpatient clinic. Participants, after signing the informed consent, fill out the survey, which included the following parameters: age, weight, height, body mass index (BMI), education, parity, shoe type, weekly walking hours, occupation, low back pain, in which semester, radiation, onset, alleviating and aggravating factors, disability, and pain in previous pregnancies. We used Excel 2010, and the Statistical Package for the Social Sciences version 23.0. p < 0.05 was considered statistically significant, and we used the Chi‐square test (χ2 test), t student test to test the basal differences between groups.ResultsA number of 551 pregnant participants were included and low back pain prevalence was 62%. There was a statistically significant relation between low back pain and each of the following: Obesity, weekly walking hours, pain in previous pregnancies, and occupation.ConclusionLow back pain is prevalent during pregnancy and the most important risk factors include obesity and pain in previous pregnancies whereas walking and employment are protective measures to prevent low back pain.
Level of agreement between midwives and obstetricians performing ultrasound examination during labor
Authors: Fidalgo Ana M. , Miguel Raquel , Fernández‐Buhigas Irene , Aguado Asunción , Cuerva Marcos J. , Corrales Elisa , Rolle Valeria , Santacruz Belén , Gil María M. , Poon Liona C. 
Published: July 2023

AbstractObjectiveTo evaluate the level of agreement between ultrasound measurements to evaluate fetal head position and progress of labor by attending midwives and obstetricians after appropriate training.MethodsIn this prospective study, women in the first stage of labor giving birth to a single baby in cephalic presentation at our Obstetric Unit between March 2018 and December 2019 were invited to participate; 109 women agreed. Transperineal and transabdominal ultrasound was independently performed by a trained midwife and an obstetrician. Two paired measurements were available for comparisons in 107 cases for the angle of progression (AoP), in 106 cases for the head‐to‐perineum distance (HPD), in 97 cases for the cervical dilatation (CD), and in 79 cases for the fetal head position.ResultsWe found a good correlation between the AoP measured by obstetricians and midwives (intra‐class correlation coefficient [ICC] = 0.85; 95% confidence interval [CI] 0.80–0.89). There was a moderate correlation between the HPD (ICC = 0.75; 95% CI 0.68–0.82). There was a very good correlation between the CD measured (ICC = 0.94; 95% CI 0.91–0.96). There was a very good level of agreement in the classification of the fetal head position (Cohen's κ = 0.89; 95% CI 0.80–0.98).ConclusionsUltrasound assessment of fetal head position and progress of labor can effectively be performed by attending midwives without previous experience in ultrasound.
Multiobjective Bayesian optimization for a 15‐dB back‐off high‐efficiency load modulated balanced amplifier design
Authors: Chen Peng , Qi Lin , Zhao Yinshuang , Yu Luqi , Yu Chao 
Published: July 2023

AbstractIn this article, multiobjecive Bayesian optimization (MBO) with a non‐penalization strategy is proposed to design a 15‐dB back‐off high‐efficiency load modulated balanced amplifier (LMBA). Applying the proposed method, the output matching networks of the LMBA are optimized to achieve proper load modulation behaviors that providing good performance. To verify the proposed method, a 2.0‐GHz LMBA is designed and measured. Experimental results show that LMBA achieves an output power of 44.5 dBm with a gain higher than 6.6 dB at saturation. The measured drain efficiency (DE)/power‐added efficiency (PAE) are 67%/52% at saturation, 54%/43% at 9‐dB back‐off, and 52%/46% at 15‐dB back‐off, respectively. Tested with 20‐MHz signal with 10‐dB peak‐to‐average power ratio (PAPR) and a 256‐quadrature amplitude modulation (QAM) scheme, the LMBA achieves adjacent channel leakage ratio (ACLR) levels of −46.7/−47.5 dBc and an error vector magnitude (EVM) of 1.2% after digital predistortion.
Synoptic characteristics of heatwave events in Australia during austral summer of 1950/1951–2019/2020
Authors: Wei Jinghua , Wang Bin , Luo Jing‐Jia , Li Chao , Yuan Chaoxia 
Published: July 2023

AbstractAustralia has experienced increasing number of heatwave events (HWEs) in recent decades. This study aims to examine key synoptic features of austral summer HWEs over Australia during 1950/1951–2019/2020. Based on ERA5‐reanalysis and rotated empirical orthogonal functions, HWEs in Australia are categorized into four types according to where they often occur together: East Australia (EA), North Australia (NA), West Australia (WA) and Southeast Australia (SEA). Our results reveal that while anomalous anticyclones at 500 hPa level are the typical synoptic circulations responsible for HWEs of each subregion, their specific mechanisms differ between subregions. The atmospheric heat budget at 850 hPa level shows that anomalous diabatic heating promotes the onset of HWEs in each subregion. While anomalous vertical advection and adiabatic heating due to the anomalous subsidence play an important role in maintaining HWEs till their demise in NA, they only help trigger HWEs in EA, SEA and WA. Our results also suggest that anomalous advection of climatological mean temperature is important to both the onset and persistence of HWEs in EA and SEA, while it only helps sustain (trigger) HWEs in NA (WA). The advection of anomalous temperature also acts to trigger HWEs in EA, SEA and WA. On the surface, upward long‐wave radiation and sensible heat flux contribute to the development of HWEs, whereas both of them are reduced in SEA due to the enhanced anomalous cyclones near the surface and the decreased land–air temperature difference. These findings help improve understanding of the synoptic characteristics and distinctive mechanisms of HWEs in different subregions of Australia.