bluuebunny/crossref_metadata_2025_split huggingface dataset:
One‐Step Synthesis of the 1‐Azaspiro[5.5]undecane Skeleton Characteristic of Histrionicotoxin Alkaloids from Linear Substrates via Hg(OTf)2‐Catalyzed Cycloisomerization
Authors: Matsumura Kunihiro , Nishikawa Keisuke , Yoshida Hiroaki , Niwa Toshiki , Fushii Yuichiro , Doe Matsumi , Morimoto Yoshiki 
Published: May 2021

AbstractHistrionicotoxin (HTX) alkaloids isolated from the poison arrow frogs possess a unique structure characterized by a 1‐azaspiro[5.5]undecane skeleton common to the HTX family. The unique molecular architecture of HTXs and the interest as potential target drugs have prompted synthetic chemists to promote the total synthesis so far. However, all of the synthetic strategies to access the 1‐azaspiro[5.5]undecane framework of HTXs take a multistep approach from linear starting materials due to stepwise construction of either six‐membered carbo‐ or azacycle. Herein, we report the direct one‐step construction of the 1‐azaspiro[5.5]undecane skeleton from linear amino ynone substrates bearing an N‐methoxycarbonyl group utilizing our mercuric triflate (Hg(OTf)2)‐catalyzed cycloisomerization reaction. The utility of this novel methodology was demonstrated by the total and formal syntheses of HTX‐235A and HTX‐283A, respectively, from the azaspirocycle.
Incorporating Guanidinium as Perovskitizer‐Cation of Two‐Dimensional Metal Halide for Crystal‐Array Photodetectors
Authors: Pan Xiong , Chen Huaixi , Lu Lei , Han Shiguo , Ma Yu , Wang Jiaqi , Guo Wuqian , Xu Haojie , Luo Junhua , Sun Zhihua 
Published: May 2021

AbstractTwo‐dimensional (2D) hybrid perovskites are recently emerging as a potential family of semiconductors for versatile optoelectronic applications. Currently, the “perovskitizer” moieties are rigidly limited to small‐size cations, while few 2D metal‐halides containing guanidinium cations inside perovskite cages have been studied for photodetection. Herein, we present a new 2D hybrid perovskite, (i‐BA)2(G)Pb2I7 (where G is guanidinium and i‐BA is isobutylammonium), which adopts a bilayered framework of {GPb2I7}. Single‐crystal structure analyses disclose that G cations act as the perovskitizer, confined in the flexible perovskite cages formed by the distorted PbI6 octahedra. Such inorganic sheets are crucial to the superior semiconducting properties and optical bandgap, as verified by the density functional theory calculation. Furthermore, its planar crystal‐array photodetector shows fascinating photoelectric performance, including a quite low dark current (∼4.6×10−11 A), a large current switching ratio (∼1.0×103), and a notable photo‐responsivity of ∼0.72 A W−1, suggesting great potential of (i‐BA)2(G)Pb2I7 for photodetection.
“Passing” and its effects on Brazilian transgender people's sense of belonging to society: A theoretical study
Authors: Dias Cristiana Kaipper , da Rocha Leonardo Rafael Leite , Tateo Luca , Marsico Giuseppina 
Published: May 2021

AbstractPassing is the research of oneself by trying to look and to be seen as a member of a social group by assuming its features. Individuals performing this process are willing to undergo several physical and behavioural changes to achieve this aspiration. Passing generally occurs among members of minority groups suffering discrimination who want to diminish the psycho‐social discomfort of their experience. Examples of passing are the attempts by ethnic minorities to whiten their skin, or the efforts of transgender people to look as much as possible, in the eyes of others, like the gender with which they identify. This paper aims to discuss aspects related to trans people's pursuit of passing, taking the Theory of Performativity of Gender and the Cultural Semiotic Psychology as its theoretical basis. This is a theoretical‐reflexive study that will debate the topic based on studies of this topic in Brazilian society.
Shengxuening Extracted from Silkworm Excrement Mitigates Myelosuppression via SCF‐Mediated JAK2/STAT3 Signaling
Authors: Ding Lu , Tan Yuxin , Xu Lulin , Jin Yanxia , Liu Yin , Tu Honglei , Zhang Dongdong , Wu Balu , Chen Yiran , Shen Hui , Liu Li , Huang Tingting , Zhou Fuling 
Published: May 2021

AbstractShengxuening (SXN) is a Chinese patent medicine with main ingredients (including chlorophyll derivatives and sodium iron chlorophyllin) extracted from silkworm excrement. SXN exhibited efficacy in clinical trials of renal anemia and iron deficiency anemia; however, the specific mechanisms remain unclear. This study found that SXN increased the number of peripheral blood cells and improved the bone marrow morphology in myelosuppressed mouse model, reversed the reduction in body weight and spleen indices, and increased the serum levels of erythropoietin and granulocyte‐macrophage colony‐stimulating factor. Quantitative real‐time PCR array and Western blot analysis showed the enhanced expression of stem cell factor (SCF), JAK2, and STAT3 in the liver. These results suggested that SXN promoted the recovery of hemopoietic function in myelosuppressed models by increasing the secretion of hematopoietic factors and activating the JAK2/STAT3 pathway. Therefore, this medicine may be applied as therapeutic pharmaceutical drug to mitigate myelosuppression.
Lies, damned lies, and statistics, but bleeding and acute limb ischemia are facts!
Authors: Damluji Abdulla A. , Gilchrist Ian C. 
Published: May 2021

Key Points
Bleeding and ischemic limb complications continue to plague patients with cardiogenic shock.
These complications are iatrogenic as they are not part of the pathophysiology of cardiogenic shock syndrome and are an attractive target for quality improvement.
Standardized care with vascular bundles may represent an important concept to reduce complications in this high‐risk patient group.
Clipping mitral valve or atrial fibrillation? Two is better than one!
Authors: Aranzulla Tiziana Claudia , Musumeci Giuseppe 
Published: May 2021

Key Points
Patients with atrial fibrillation (AF) undergoing MitraClip experience a doubled risk of in‐hospital stroke and higher 30‐day mortality.
Strategies to prevent in‐hospital stroke in AF patients undergoing MitraClip may involve both pre‐ and intra‐procedural management.
Specific trials are needed to assess the impact of uninterrupted anticoagulation, early heparinization, and previous AF ablation on outcome following MitraClip.
Achieving radiation reduction by adapting to technology advances
Authors: Balter Stephen , Moses Jeffrey W. 
Published: May 2021

Key Points
This study demonstrates that the combination of image processing enhancements along with meticulous attention by operators to radiation hygiene can lead to significant and clinically meaningful reductions in radiation exposure.
The results obtained from a single experienced chronic total occlusion (CTO) operator in two sequential time periods are a reasonable substitute for a randomized trial.
Radiation exposure to patients and operators remains a significant hazard of CTO procedures.
Avoiding excessive dosage removes a barrier to successful procedural completion.
The prognostic significance of electrocardiography findings in patients with coronavirus disease 2019: A retrospective study
Authors: Yang Deyan , Li Jing , Gao Peng , Chen Taibo , Cheng Zhongwei , Cheng Kangan , Deng Hua , Fang Quan , Yi Chunfeng , Fan Hongru , Wu Yonghong , Li Liwei , Fang Yong , Tian Guowei , Pan Wan , Zhang Fan 
Published: May 2021

AbstractBackgroundCoronavirus disease 2019 (COVID‐19) has reached a pandemic level. Cardiac injury is not uncommon among COVID‐19 patients. We sought to describe the electrocardiographic characteristics and to identify the prognostic significance of electrocardiography (ECG) findings of patients with COVID‐19.HypothesisECG abnormality was associated with higher risk of death.MethodsConsecutive patients with laboratory‐confirmed COVID‐19 and definite in‐hospital outcome were retrospectively included. Demographic characteristics and clinical data were extracted from medical record. Initial ECGs at admission or during hospitalization were reviewed. A point‐based scoring system of abnormal ECG findings was formed, in which 1 point each was assigned for the presence of axis deviation, arrhythmias, atrioventricular block, conduction tissue disease, QTc interval prolongation, pathological Q wave, ST‐segment change, and T‐wave change. The association between abnormal ECG scores and in‐hospital mortality was assessed in multivariable Cox regression models.ResultsA total of 306 patients (mean 62.84 ± 14.69 years old, 48.0% male) were included. T‐wave change (31.7%), QTc interval prolongation (30.1%), and arrhythmias (16.3%) were three most common found ECG abnormalities. 30 (9.80%) patients died during hospitalization. Abnormal ECG scores were significantly higher among non‐survivors (median 2 points vs 1 point, p < 0.001). The risk of in‐hospital death increased by a factor of 1.478 (HR 1.478, 95% CI 1.131–1.933, p = 0.004) after adjusted by age, comorbidities, cardiac injury and treatments.ConclusionsECG abnormality was common in patients admitted for COVID‐19 and was associated with adverse in‐hospital outcome. In‐hospital mortality risk increased with increasing abnormal ECG scores.
Aspirin, ibuprofen, and reduced risk of advanced colorectal adenoma incidence and recurrence and colorectal cancer in the PLCO Cancer Screening Trial
Authors: Chudy‐Onwugaje Kenechukwu , Huang Wen‐Yi , Su L. Joseph , Purdue Mark P. , Johnson Christine C. , Wang Lingxiao , Katki Hormuzd A. , Barry Kathryn Hughes , Berndt Sonja I. 
Published: May 2021

BackgroundStudying the differential impact of aspirin and other nonsteroidal anti‐inflammatory drugs across the stages of colorectal neoplasia from early adenoma to cancer is critical for understanding the benefits of these widely used drugs.MethodsWith 13 years of follow‐up, the authors prospectively evaluated the association between aspirin and ibuprofen use and incident distal adenoma (1221 cases), recurrent adenoma (862 cases), and incident colorectal cancer (CRC; 2826 cases) among men and women in the population‐based Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. With multivariable‐adjusted models, odds ratio (ORs) and 95% confidence intervals (CIs) for adenoma incidence and recurrence and hazard ratios (HRs) and 95% CIs for incident CRC were determined.ResultsThe authors observed a significantly reduced risk of incident adenoma with ibuprofen use (≥30 vs <4 pills per month: OR, 0.76 [95% CI, 0.60‐0.95]; Ptrend = .04), particularly advanced adenoma (OR, 0.48 [95% CI, 0.28‐0.83]; Ptrend = .005). Among those with a previous adenoma detected through screening, aspirin use was associated with a decreased risk of advanced recurrent adenoma (≥30 vs <4 pills per month: OR, 0.56 [95% CI, 0.36‐0.87]; Ptrend = 0.006). Both aspirin (HR, 0.88 [95% CI, 0.81‐0.96]; Ptrend <.0001) and ibuprofen use (HR, 0.81 [95% CI, 0.70‐0.93); Ptrend = 0.003) ≥30 versus <4 pills per month were significantly associated with reduced CRC risk.ConclusionsIn this large prospective study with long‐term follow‐up, a beneficial role for not only aspirin, but also ibuprofen, in preventing advanced adenoma and curbing progression to recurrence and cancer among older adults was observed.
Subphthalocyanine‐Diketopyrrolopyrrole Conjugates: 3D Star‐Shaped Systems as Non‐Fullerene Acceptors in Polymer Solar Cells with High Open‐Circuit Voltage
Authors: Álvaro‐Martins Maria J. , Sánchez José G. , Lavarda Giulia , Molina Desiré , Pallarès Josep , Torres Tomás , Marsal Lluis F. , Sastre‐Santos Ángela 
Published: May 2021

AbstractFour star‐shaped electron acceptors (C1‐OPh, C3‐OPh, C1‐Cl and C3‐Cl) based on a subphthalocyanine core bearing three diketopyrrolopyrrole wings linked by an acetylene bridge have been synthesized. These derivatives feature two different axial substituents (i. e., 4‐tert‐butylphenoxy (OPh) or chlorine (Cl)) and for each of them, both the C1 and the C3 regioisomers have been investigated. The four compounds exhibit a broad absorption band in the 450–700 nm region, with bandgap values near to 2 eV. These materials were applied in the active layer of inverted bulk‐heterojunction polymer solar cells in combination with the donor polymer PBDB‐T. Derivatives bearing the OPh axial group showed the best performances, with C1‐OPh being the most promising with a PCE of 3.27 % and a Voc as high as 1.17 V. Despite presenting the widest absorption range, the photovoltaic results obtained with C1‐Cl turned out to be the lowest (PCE=1.01 %).
Photoassisted Charge Transfer Between DMF and Substrate: Facile and Selective N,N‐Dimethylamination of Fluoroarenes
Authors: Ansari Tharique N. , Sharma Sudripet , Bora Pranjal P. , Ogulu Deborah , Parmar Saurav , Gallou Fabrice , Kozlowski Pawel M. , Handa Sachin 
Published: May 2021

AbstractA reversible Van der Waals complex formation between the electron‐deficient fluorinated aromatic ring and N,N‐dimethylformamide (DMF) molecules followed by light irradiation resulted in charge transfer (CT) process. The complex was stabilized by ammonium formate and further decomposed to form the C−N bond. Control experiments revealed that the simultaneous SNAr pathway also contributes to product formation. This methodology is mild, metal‐free, and effective for the amination of a variety of substrates. The reproducibility of this methodology was also verified on gram‐scale reactions. The CT states were supported by control UV/Vis spectroscopy and computational studies.
Molecular Triad Containing a TEMPO Catalyst Grafted on Mesoporous Indium Tin Oxide as a Photoelectrocatalytic Anode for Visible Light‐Driven Alcohol Oxidation
Authors: Pati Palas Baran , Abdellah Mohamed , Diring Stéphane , Hammarström Leif , Odobel Fabrice 
Published: May 2021

AbstractPhotoelectrochemical cells based on semiconductors are among the most studied methods of artificial photosynthesis. This study concerns the immobilization, on a mesoporous conducting indium tin oxide electrode (nano‐ITO), of a molecular triad (NDADI−P−Ru‐TEMPO) composed of a ruthenium tris‐bipyridine complex (Ru) as photosensitizer, connected at one end to 2,2,6,6‐tetramethyl‐1‐piperidine N‐oxyl (TEMPO) as alcohol oxidation catalyst and at the other end to the electron acceptor naphthalenedicarboxyanhydride dicarboximide (NDADI). Light irradiation of NDADI−P−Ru‐TEMPO grafted to nano‐ITO in a pH 10 carbonate buffer effects selective oxidation of para‐methoxybenzyl alcohol (MeO−BA) to para‐methoxybenzaldehyde with a TON of approximately 150 after 1 h of photolysis at a bias of 0.4 V vs. SCE. The faradaic efficiency is found to be of 80±5 %. The photophysical study indicates that photoinduced electron transfer from the Ru complex to NDADI is a slow process and must compete with direct electron injection into ITO to have a better performing system. This work sheds light on some of the important ways to design more efficient molecular systems for the preparation of photoelectrocatalytic cells based on catalyst‐dye‐acceptor arrays immobilized on conducting electrodes.
Gastrointestinal symptomatology, diagnosis, and treatment history in patients with underweight avoidant/restrictive food intake disorder and anorexia nervosa: Impact on weight restoration in a meal‐based behavioral treatment program
Authors: Cooper Marita , Collison Amira O. , Collica Sarah C. , Pan Isabella , Tamashiro Kellie L. , Redgrave Graham W. , Schreyer Colleen C. , Guarda Angela S. 
Published: May 2021

AbstractObjectiveGastrointestinal (GI) concerns are often presumed to complicate nutritional rehabilitation for restrictive eating disorders, yet their relationship to weight restoration outcomes is unclear. This retrospective chart review examined GI history and weight‐related discharge outcomes in primarily adult, underweight inpatients with anorexia nervosa (AN, N = 107) or avoidant/restrictive food intake disorder (ARFID, N = 22) treated in a meal‐based, behavioral eating disorder program.MethodLifetime GI symptomatology, diagnoses, diagnostic tests, and procedures were abstracted from medical records. Generalized linear models examined associations of GI diagnoses, tests, and procedures with discharge BMI and rate of weight gain.ResultsNinety‐nine percent of patients reported GI symptomatology and 83% had one or more GI diagnoses; with constipation and GERD most common. GI diagnoses (p <.01) and testing (p <.001) were more common in ARFID than AN. Average inpatient weight gain (1.59 kg/week), and discharge BMI (18.5 kg/m2), did not differ by group. Slower weight gain in patients with (1.3 kg/week), versus without (1.7 kg/week), history of tube feeding (p = .02), accounted for a main effect of GI procedures on inpatient rate of gain (p = .01).DiscussionDespite ubiquitous GI symptomatology, meal‐based weight restoration achieved average weekly weight gain above recommended APA guidelines for hospitalized patients with an eating disorder. History of tube feeding was associated with slower mean weight gain, which remained, however, within recommended APA guidelines.
The effect of competing carnivores on the feeding behaviour of leopards (Panthera pardus) in an African savanna
Authors: Tarugara Allan , Clegg Bruce W. , Gandiwa Edson , Muposhi Victor K. 
Published: May 2021

AbstractKnowledge of competition dynamics among Africa’s large carnivores is important for conservation. However, investigating carnivore behaviour in the field can be challenging especially for species that are difficult to access. Methods that enable remote collection of data provide a means of recording natural behaviour and are therefore useful for studying elusive species such as leopards (Panthera pardus). Camera traps and Global Positioning System (GPS) collars are powerful tools often used independently to study animal behaviour but where their data are combined, the interpretation of a species’ behaviours is improved. In this study we used data from baited camera trap stations to investigate the feeding habits of leopards at Malilangwe Wildlife Reserve, Zimbabwe. We investigated the influence of spotted hyenas, lions and other competing leopards on the feeding duration of leopards using Generalized Linear Mixed Effects Modelling. To test the influence of competing predators on resting distances from bait sites, eight leopards were fitted with GPS collars. Results showed that leopards spent the shortest time feeding on the baits in the presence of competing male leopards compared to other predators while lion presence caused animals to rest farthest from bait sites. Interaction analysis indicated that small‐bodied leopards spent significantly shorter durations feeding when spotted hyenas were present. Our findings demonstrate that competition from guild carnivores has negative impacts on the food intake of leopards, which may have implications for fitness and survival. This study provides a snapshot of the competition dynamics at bait sites which may give insight to ecosystem level interactions among large carnivores in savanna ecosystems.
Global change impacts on arid zone ecosystems: Seedling establishment processes are threatened by temperature and water stress
Authors: Lewandrowski Wolfgang , Stevens Jason C. , Webber Bruce L. , L. Dalziell Emma , Trudgen Melinda S. , Bateman Amber M. , Erickson Todd E. 
Published: May 2021

AbstractRecruitment for many arid‐zone plant species is expected to be impacted by the projected increase in soil temperature and prolonged droughts associated with global climate change. As seed dormancy is considered a strategy to avoid unfavorable conditions, understanding the mechanisms underpinning vulnerability to these factors is critical for plant recruitment in intact communities, as well as for restoration efforts in arid ecosystems. This study determined the effects of temperature and water stress on recruitment processes in six grass species in the genus Triodia R.Br. from the Australian arid zone. Experiments in controlled environments were conducted on dormant and less‐dormant seeds at constant temperatures of 25°C, 30°C, 35°C, and 40°C, under well‐watered (Ψsoil = −0.15 MPa) and water‐limited (Ψsoil = −0.35 MPa) conditions. Success at three key recruitment stages—seed germination, emergence, and survival—and final seed viability of ungerminated seeds was assessed. For all species, less‐dormant seeds germinated to higher proportions under all conditions; however, subsequent seedling emergence and survival were higher in the more dormant seed treatment. An increase in temperature (35–40°C) under water‐limited conditions caused 95%–100% recruitment failure, regardless of the dormancy state. Ungerminated seeds maintained viability in dry soil; however, when exposed to warm (30–40°C) and well‐watered conditions, loss of viability was greater from the less‐dormant seeds across all species. This work demonstrates that the transition from seed to established seedling is highly vulnerable to microclimatic constraints and represents a critical filter for plant recruitment in the arid zone. As we demonstrate temperature and water stress‐driven mortality between seeds and established seedlings, understanding how these factors influence recruitment in other arid‐zone species should be a high priority consideration for management actions to mitigate the impacts of global change on ecosystem resilience. The knowledge gained from these outcomes must be actively incorporated into restoration initiatives.
Wildfire impacts on forest microclimate vary with biophysical context
Authors: Wolf Kyra D. , Higuera Philip E. , Davis Kimberley T. , Dobrowski Solomon Z. 
Published: May 2021

AbstractIncreasing wildfire activity in western North America has the potential to remove forest canopy cover over large areas, increasing the vulnerability of understory plants and juvenile trees to microclimatic extremes. To understand the impacts of wildfire on forest microclimatic buffering, we monitored daily temperature and vapor pressure deficit (VPD) in 33 plots over the first two growing seasons following two wildfires from 2017. The Lolo Peak and Sunrise fires occurred during a regionally extensive fire season, burning mixed‐conifer and subalpine forests across complex mountainous topography in western Montana. Sensors were deployed from June to September in 2018 and 2019 in sites stratified by aspect, elevation, and fire severity (unburned, moderate, high) to capture a range of forest types, biophysical contexts, and fire effects. Loss of canopy and understory vegetation had marked effects on microclimate: On average, sites burned at high severity had 3.7°C higher daily maximum temperatures and 0.81 kPa higher daily maximum VPD relative to paired unburned sites. Differences between burned and unburned sites were most pronounced when ambient temperatures were high, across diurnal and seasonal time scales. Differences were also more pronounced at sites with less canopy cover, more bare ground postfire, and greater long‐term water availability (i.e., low climatic water deficit). Our results reveal fire‐caused changes in microclimate extremes that are biologically meaningful for the postfire establishment of tree seedlings and understory vegetation. These effects depend strongly on biophysical context, with cool‐wet forests more vulnerable to fire‐caused changes in microclimate compared with warm‐dry settings. Our results further highlight the functional importance of standing dead trees for moderating surface temperature in postfire environments. Anticipating forest ecosystem responses to increased warming and wildfire activity, and the potential for fire to catalyze vegetation changes, thus requires considering the substantial impacts of fire on microclimate.