bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrathin Two‐Dimensional Metal–Organic Framework Nanosheets Based on a Halogen‐Substituted Porphyrin Ligand: Synthesis and Catalytic Application in CO2 Reductive Amination
Authors: Dong Jurong , Mo Qijie , Wang Yufei , Jiang Long , Zhang Li , Su Cheng‐Yong 
Published: May 2022

AbstractUltrathin two‐dimensional metal–organic framework nanosheets have emerged as a promising kind of heterogeneous catalysts. Herein, we report a series of 2D porphyrinic metal–organic framework nanosheets (X‐PMOF, X=F, Cl, Br), which was prepared from the self‐assembly of a halogen‐based porphyrin ligand X‐TCPP (X‐TCPP=5‐(4‐halogenatedphenyl)‐10,15,20‐tris(4‐carboxyphenyl)‐porphyrin) and ZrCl4 in the presence of trifluoroacetic acid as the modulating reagent. The framework of X‐PMOF possessed the ftw topology as in MOF‐525. The lamellar X‐PMOF nanosheets with the thickness of down to 4.5 nm were assembled and aggregated into a flower‐like morphology. With the introduction of iridium(III) atoms into the porphyrin rings, the resultant X‐PMOF(Ir) nanosheets were prepared by a similar method. Catalytic results show that Br‐PMOF(Ir) nanosheets were efficient for CO2 reduction and aminolysis, giving rise to formamides in high yields under room temperature and atmospheric pressure, and can be recycled and reused for 3 runs. The total turnover number of Br‐PMOF(Ir) after 3 runs was 1644 based on Ir. Mechanistic studies disclose that the high efficiency of Br‐PMOF(Ir) nanosheets was ascribed to three factors, including the superior activation capability of iridium(III) porphyrin for Si−H bonds, more active sites on the external surfaces of Br‐PMOF(Ir) nanosheets, and the defects caused by unsymmetrical porphyrin ligand that increased the framework's affinity towards CO2.
Recent Advances in the Synthesis and Biological Applications of Peptidoglycan Fragments
Authors: Vacariu Condurache M. , Tanner Martin E. 
Published: May 2022

AbstractThe biosynthesis, breakdown, and modification of peptidoglycan (PG) play vital roles in both bacterial viability and in the response of human physiology to bacterial infection. Studies on PG biochemistry are hampered by the fact that PG is an inhomogeneous insoluble macromolecule. Chemical synthesis is therefore an important means to obtain PG fragments that may serve as enzyme substrates and elicitors of the human immune response. This review outlines the recent advances in the synthesis and biochemical studies of PG fragments, PG biosynthetic intermediates (such as Park's nucleotides and PG lipids), and PG breakdown products (such as muramyl dipeptides and anhydro‐muramic acid‐containing fragments). A rich variety of synthetic approaches has been applied to preparing such compounds since carbohydrate, peptide, and phospholipid chemical methodologies must all be applied.
Hierarchically Porous Poly(ionic liquid) – Organic Cage Composite Membrane for Efficient Iodine Capture
Authors: Zhao Xue‐Jing , Liu Si‐Hua , Sun Jian‐Ke 
Published: May 2022

AbstractThe effective capture of iodine with high volatility and poisonousness is significant for reprocessing the spent nuclear fuel. In this article, we report a hierarchically porous poly(ionic liquid)‐organic cage composite membrane (PIL@CC3) possessing a gradient content distribution of CC3 cage crystals throughout the membrane to capture iodine vapor. The introduction of microporous CC3 can significantly enhance the uptake capacity of iodine up to 980 mg g−1, which is superior to that of a pristine PIL membrane carrying large meso‐ and macropores (99 mg g−1), and CC3 crystalline powder (662 mg g−1). Such enhanced performance benefits from the micro‐meso‐macroporous structure of the PIL@CC3 membrane in which the large meso‐ and macropores facilitate the mass transfer of iodine molecules from the external environment into the surface of the CC3 crystal, followed by diffusion of iodine molecules from the CC3 surface into the interior and exterior pores of the CC3 crystal. In addition, the asymmetric distribution of CC3 crystals across the PIL@CC3 membrane also displays its advantage in intercepting trace iodine, revealing its great potential for practical application. This study provides an idea for constructing hierarchically porous membrane composites for the removal of toxic vapors.
Lewis Acid Assisted Brønsted Acid Catalysed Decarbonylation of Isocyanates: A Combined DFT and Experimental Study
Authors: Dasgupta Ayan , van Ingen Yara , Guerzoni Michael G. , Farshadfar Kaveh , Rawson Jeremy M. , Richards Emma , Ariafard Alireza , Melen Rebecca L. 
Published: May 2022

AbstractAn efficient and mild reaction protocol for the decarbonylation of isocyanates has been developed using catalytic amounts of Lewis acidic boranes. The electronic nature (electron withdrawing, electron neutral, and electron donating) and the position of the substituents (ortho/meta/para) bound to isocyanate controls the chain length and composition of the products formed in the reaction. Detailed DFT studies were undertaken to account for the formation of the mono/di‐carboxamidation products and benzoxazolone compounds.
Opioid Ligands Addressing Unconventional Binding Sites and More Than One Opioid Receptor Subtype
Authors: Drakopoulos Antonios , Moianos Dimitrios , Prifti Georgia‐Myrto , Zoidis Grigoris , Decker Michael 
Published: May 2022

AbstractOpioid receptors (ORs) represent one of the most significant groups of G‐protein coupled receptor (GPCR) drug targets and also act as prototypical models for GPCR function. In a constant effort to develop drugs with less side effects, and tools to explore the ORs nature and function, various (poly)pharmacological ligand design approaches have been performed. That is, besides classical ligands, a great number of bivalent ligands (i. e. aiming on two distinct OR subtypes), univalent heteromer‐selective ligands and bitopic and allosteric ligands have been synthesized for the ORs. The scope of our review is to present the most important of the aforementioned ligands, highlight their properties and exhibit the current state‐of‐the‐art pallet of promising drug candidates or useful molecular tools for the ORs.
Potentially traumatic events and post‐traumatic growth among Chinese peacekeepers: A moderated mediation model
Authors: Qu Jingrui , Tu Zhihao , Zheng Xican , Wang Minjie , Shen Xinghua 
Published: May 2022

AbstractPeacekeepers are inherently exposed to potentially traumatic events (PTEs) in the line of duty. However, little is known about whether PTEs during peacekeeping missions may foster post‐traumatic growth (PTG) among peacekeepers and its mechanisms. This study aimed to investigate the association between PTEs and PTG among Chinese peacekeepers, as well as the mediating role of coping style and the moderating role of resilience. Five hundred ninety‐five Chinese peacekeepers completing the United Nations (UN) peacekeeping mission in South Sudan and returning to China were recruited to complete Peacekeeping Traumatic Stress Exposure Scale, Posttraumatic Growth Inventory, Simplified Coping Style Questionnaire and the Chinese version of Connor and Davidson's Resilience Scale. PTEs were positively associated with PTG among Chinese peacekeepers. Coping style partially mediated the association between PTEs and PTG. Resilience moderated the association between coping style and PTG. Specifically, at a lower level of resilience, positive coping style was more effective in predicting PTG. This study contributes to understanding the complex association between PTEs in peacekeeping missions, coping style, resilience and PTG by focusing on the experiences of Chinese peacekeepers and adds value to the current literature on psychological health in peacekeepers.
Early stages of speciation with gene flow in the Amazilia Hummingbird (Amazilis amazilia) subspecies complex of Western South America
Authors: Cowles Sarah A. , Witt Christopher C. , Bonaccorso Elisa , Grewe Felix , Uy J. Albert C. 
Published: May 2022

AbstractDisentangling the factors underlying the diversification of geographically variable species with a wide geographical range is essential to understanding the initial stages and drivers of the speciation process. The Amazilia Hummingbird, Amazilis amazilia, is found along the Pacific coast from northern Ecuador down to the Nazca Valley of Peru, and is currently classified as six phenotypically differentiated subspecies. We aimed to resolve the evolutionary relationships of the six subspecies, to assess the geographical pattern and extent of evolutionary divergence, and to test for introgression using both a mtDNA marker and a genome‐by‐sequencing dataset from 86 individuals from across the species range. The consensus phylogenetic tree separated the six subspecies into three distinct clades, corresponding with the Ecuador lowlands (A. amazilia dumerilii), the Ecuador highlands (A. amazilia alticola and A. amazilia azuay), and the Peruvian coast (A. amazilia leucophoea, A. amazilia amazilia, and A. amazilia caeruleigularis). However, an unresolved mtDNA network suggests that the diversification of the subspecies was recent and rapid. We found evidence of gene flow among the subspecies A. amazilia dumerilii, A. amazilia alticola, and A. amazilia leucophoea, with strong genetic isolation of the subspecies A. amazilia azuay in the isolated Yunguilla Valley of Ecuador. Finally, environmental data from each subspecies’ capture locations were concordant with the three distinct clades. Overall, our results suggest that both expansions into new habitats and geographic isolation shaped the present‐day phylogeny and range of the A. amazilia subspecies, and that A. amazilia azuay may be genetically divergent enough to be considered a separate species.
Genetic diversity and demographic history of the Old World Bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), in Ethiopia inferred from mitochondrial gene sequences
Authors: Fite Tarekegn , Tefera Tadele , Goftishu Muluken , Damte Tebekew 
Published: May 2022

AbstractThe Old World bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), is a globally distributed agricultural and horticultural insect pest. Despite the economic importance of this insect in Ethiopia, its genetic diversity and demographic history are poorly understood. We examined the nucleotide variation of the mitochondrial cytochrome c oxidase subunit I (COI) gene fragment of 74 H. armigera individuals from six collection sites in Ethiopia. We recorded 15 COI haplotypes in H. armigera, ten globally shared and five exclusive to Ethiopia (HaET15, HaET14, HaET10, HaET7, and HaET4). Haplotype HaET1 was the most widely geographically distributed and frequent (71.62%). Analysis of molecular variance (AMOVA) revealed a high and significant level of variation within H. armigera populations (θST = −0.0135). Negative values of the neutrality test and nonsignificant index of mismatch distribution supported the demographic expansion of H. armigera populations in Ethiopia; furthermore, this was also supported by the nonsignificant values of the sum of squared deviations (SSD) and raggedness index (r). The high genetic variation and population expansion of H. armigera have immense implications for devising locally adapted management strategies in area‐wide integrated pest management IPM programs. However, a comprehensive study of H. armigera genetic diversity and population structure using various molecular markers is needed for future confirmation.
Phenotypic responses to light, water, and nutrient conditions in the allopolyploid Arabidopsis suecica and its parent species A. thaliana and A. arenosa: Does the allopolyploid outrange its parents?
Authors: Kornstad Torbjørn , Ohlson Mikael , Fjellheim Siri 
Published: May 2022

AbstractPolyploid species possess more than two sets of chromosomes and may show high gene redundancy, hybrid vigor, and masking of deleterious alleles compared to their parent species. Following this, it is hypothesized that this makes them better at adapting to novel environments than their parent species, possibly due to phenotypic plasticity. The allopolyploid Arabidopsis suecica and its parent species A. arenosa and A. thaliana were chosen as a model system to investigate relationships between phenotypic plasticity, fitness, and genetic variation. Particularly, we test if A. suecica is more plastic, show higher genetic diversity, and/or have higher fitness than its parent species. Wild Norwegian populations of each species were analyzed for phenotypic responses to differences in availability of nutrient, water, and light, while genetic diversity was assessed through analysis of AFLP markers. Arabidopsis arenosa showed a higher level of phenotypic plasticity and higher levels of genetic diversity than the two other species, probably related to its outbreeding reproduction strategy. Furthermore, a general positive relationship between genetic diversity and phenotypic plasticity was found. Low genetic diversity was found in the inbreeding A. thaliana. Geographic spacing of populations might explain the clear genetic structure in A. arenosa, while the lack of structure in A. suecica could be due to coherent populations. Fitness measured as allocation of resources to reproduction, pointed toward A. arenosa having lower fitness under poor environmental conditions. Arabidopsis suecica, on the other hand, showed tendencies toward keeping up fitness under different environmental conditions.
The benefits of merging passive and active tracking approaches: New insights into riverine migration by salmonid smolts
Authors: Chavarie Louise , Honkanen Hannele M. , Newton Matthew , Lilly Jessie M. , Greetham Hannah R. , Adams Colin E. 
Published: May 2022

AbstractThe process of smolting is a critical phase in the life cycle of anadromous salmonids, and it has been associated with substantial rates of mortality. Survival during freshwater and marine migration is known to have population‐level effects; thus, an understanding of the patterns of mortality has the potential to yield important insights into population bottlenecks. Despite important advancements in tracking techniques, the specifics of mortality events in anadromous salmonids during their initial migration to sea remain somewhat elusive. Here, we develop a framework combining spatial and temporal detections of smolt riverine migration from two tracking techniques, which enable inferences to be made about mortality locations, causes, and rates. In this study, we demonstrate that during their initial riverine transitional phase, smolts were particularly vulnerable to predators. Specifically, avian predation appeared to be the main cause of mortality (42%), although piscine predation events were not trivial (14%). Our results suggested some direct and indirect tagging‐induced mortality (e.g., through increased predation vulnerability), which highlights the importance of determining tagging mortality in a telemetry study to ensure adequate interpretation of migration success. Overall, by estimating migration loss and its variability, our study framework should help to guide management actions to mitigate the widespread population declines these species are currently facing.
Tropical montane forest in South Asia: Composition, structure, and dieback in relation to soils and topography
Authors: Lakkana Tithira , Ashton Mark S. , Hooper Elaine R. , Perera Anoma , Ediriweera Sisira 
Published: May 2022

AbstractWe evaluated the composition, structure, and dieback of a montane forest in relation to soils and physiography of an important biogeographic region that has been sparsely studied. Our objectives were to (1) describe the forest composition and structure; (2) assess the current extent of dieback; and (3) relate tree composition, structure, and dieback proneness to edaphic and physiographic measures. We enumerated all live and dead standing plants ≥3 cm dbh, in thirty 20 × 15 m2 overstory plots. We measured all regeneration ≤1 m height in subplots, sampled soils and measures of physiography, and visually rated the proportion of crown dieback, and recorded standing dead trees. Woody plants belonged to 58 species and 25 families, of which 5% were dead. The plant families Lauraceae, Myrtaceae, and Symplocaceae represented over 50% of the basal area; Rubiaceae alone represented 25% of the stems. Multiple regressions revealed measures of edaphic and physiographic factors are associated with tree species richness and diversity, structure (e.g., basal area and stem density), and tree dieback and standing dead trees. Canopy openness and measures of soil toxicity from metals (Al and Cu) on clay‐based soils showed a predictably negative relationship with tree species richness and diversity. Basal area and stem density are positively associated with aspect and slope, and predictably negatively associated with canopy openness. Lastly, dieback and standing dead trees of the dominant canopy tree species are both positively associated with south and southwest aspects. The forest is now in a period of regeneration recovery with high numbers of regenerating secondary successional species. We propose the primary underlying factors that caused the dieback of this forest was a drought during 1970–1980 compounded by accumulations of salts and metals in the soil conveyed by winds from the sea (sodium) and from an ancient period of metallurgy downwind of the forest. However, our results are only suggestive of these causative factors and further study is necessary to confirm or refute these speculative causes for dieback.
Multimorbidity, guideline‐directed medical therapies, and associated outcomes among hospitalized heart failure patients
Authors: Takeuchi Shinsuke , Kohno Takashi , Goda Ayumi , Shiraishi Yasuyuki , Kawana Masataka , Saji Mike , Nagatomo Yuji , Nishihata Yosuke , Takei Makoto , Nakano Shintaro , Soejima Kyoko , Kohsaka Shun , Yoshikawa Tsutomu ,   West Tokyo Heart Failure Registry Investigators
Published: May 2022

AbstractAimsMultimorbidity is common among heart failure (HF) patients and may attenuate guideline‐directed medical therapy (GDMT). Multimorbid patients are under‐represented in clinical trials; therefore, the effect of multimorbidity clustering on the prognosis of HF patients remains unknown. We evaluated the prevalence of multimorbidity clusters among consecutively registered hospitalized HF patients and assessed whether GDMT attenuated outcomes.Methods and resultsWe examined 1924 hospitalized HF patients with reduced left ventricular ejection fraction (<50%) in a multicentre registry (West Tokyo HF Registry: WET‐HF). Ten comorbid conditions in the WET‐HF were abstracted: coronary artery disease, atrial fibrillation, stroke, anaemia, chronic obstructive pulmonary disease, renal dysfunction, obesity, hypertension, dyslipidaemia, and diabetes. Patients were divided into three groups (0–2: n = 451; 3–4: n = 787; and ≥5: n = 686) based on the number of comorbid conditions. The primary composite endpoint was all‐cause mortality and HF rehospitalization. The most prevalent comorbidities were renal dysfunction (67.9%), hypertension (66.0%), and anaemia (53.8%). Increased comorbidity was associated with increased adverse outcomes [3–4: hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.13–1.77, P = 0.003; ≥5: HR 2.12, 95%CI 1.69–2.65, P < 0.001; and reference: 0–2] and lower GDMT prescription rate (0–2: 69.2%; 3–4: 57.7%; and ≥5: 57.6%). GDMT was associated with decreased adverse outcomes; this association was maintained even as the comorbidity burden increased but tended to weaken (0–2: HR 0.53, 95%CI 0.35–0.78; P = 0.001; 3–4: HR 0.82, 95%CI 0.65–1.04, P = 0.095; and ≥5: HR 0.81, 95%CI 0.65–1.00, P = 0.053; P for interaction = 0.156).ConclusionsComorbidity clusters were prevalent and associated with poorer outcomes. GDMT remained beneficial regardless of the comorbidity burden but tended to weaken with increasing comorbidity burden. Further research is required to optimize medical care in these patients.
Ruthenium‐Catalyzed Intermolecular Cyclization and N‐Methylation of Salicyl N‐Tosylhydrazones
Authors: Kurma Siva Hariprasad , Kolla Sai Teja , Sridhar Balasubramanian , Bhimapaka China Raju 
Published: May 2022

Abstract3‐(2,2‐dichloroacetyl)‐2H‐Chromen‐2‐ones were prepared by treating salicyl N‐tosylhydrazones with ethyl 4,4,4‐trichloro‐3‐oxobutanoate in presence of catalytic amount of La(OTf)3 and RuCl3 ⋅ 3H2O for the first time. The chromenones were formed through C‐C, C‐O bond formations, detosylation and more importantly dechlorination protocol. One of the compound 3‐(2,2‐dichloroacetyl)‐6‐methyl‐2H‐chromen‐2‐one structure was confirmed by single‐crystal X‐ray analysis. Further, salicyl N‐tosylhydrazones when treated with dimethyl (1‐diazo‐2‐oxopropyl)‐phosphonate (Bestmann‐Ohira reagent) in presence of K2CO3 and RuCl3 ⋅ 3H2O provided (E)‐N′‐(2‐hydroxybenzylidene)‐N,4‐dimethylbenzenesulfono hydrazide.
Geographical reconfiguration in global value chains: Search within limited space?
Authors: Rodriguez Carlos , Ciravegna Luciano , Petersen Bent 
Published: May 2022

AbstractResearch summaryNegative performance feedback in offshoring service activities entices firms to undertake geographical reconfiguration of their global value chains (GVCs) as a substitute for, or complement to, change of governance modes, decomposition of offshored activities, or shift of local service providers. In this study, we build on performance feedback theory and the concept of problemistic search to examine the extent to which firms move offshored service activities to new countries when facing negative performance gaps. We also examine if these relocations take place within a search space limited by the managers' cognitive span. We formulate a set of hypotheses revolving around this idea of search within a limited space. Our hypotheses are supported when tested on a sample of global sourcing projects undertaken by 223 firms between 1995 and 2012.Managerial summaryThe essence of reconfiguration is the continuous search for efficient combinations of functions, local service providers (when functions are outsourced), governance modes, and—in our case—locations. Limiting the search for improved combinations to fewer locations entails a higher dependence on these locations maintaining the country‐location‐specific advantages that made them attractive in the first place. It is thus possible that multinational enterprise (MNE) managers who reconfigure their GVC in a geographically bounded way in the long run will struggle to compete with MNEs that search for optimality within a broader range of locations as possible remedies for the GVC operations that experience negative performance gaps.
Evaluation of subclasses for T4‐classified squamous cell carcinoma of the external auditory canal
Authors: Nabuurs Cindy H. , Kievit Wietske , Leemans C. René , Smit Conrad F. G. M. , van den Brekel Michiel W. M. , Pauw Robert J. , van der Laan Bernard F. A. M. , Jansen Jeroen C. , Lacko Martin , Braunius Weibel W. , Dai Chunfu , Shi Xunbei , Danesi Giovanni , Bouček Jan , Takes Robert P. , Kunst Henricus P. M. 
Published: May 2022

AbstractBackgroundT4‐classified squamous cell carcinoma (SCC) of external auditory canal (EAC) can potentially involve different anatomical structures, which could translate into different treatment strategies and survival outcomes within one classification. Our aim is to evaluate the clinical added value of T4‐subclasses proposed by Lavieille and by Zanoletti.MethodsRetrospective data, including patients with primary operated cT4‐classified EAC SCC, was obtained from 12 international hospitals. We subclassified according to the T4‐subclasses. The treatment strategies, disease‐free survival (DFS) and overall survival per subclass were calculated.ResultsA total of 130 T4‐classified EAC SCC were included. We found commonly used treatment strategies per subclass according to Lavieille and the DFS seems also to differ per subclass. Subclass according to Zanoletti showed comparable treatment strategies and survival outcomes per subclass.ConclusionOur study suggests that the subclass according Lavieille might have added value in clinical practice to improve care of T4‐classified EAC SCC.