bluuebunny/crossref_metadata_2025 huggingface dataset:
Low‐Valent Titanium Species Stabilized with Aluminum/Boron Hydride Fragments
Authors: del Horno Estefanía , Jover Jesús , Mena Miguel , Pérez‐Redondo Adrián , Yélamos Carlos
Published: November 2021

Low‐valent titanium species were prepared by reaction of [TiCp*X3] (Cp*=η5‐C5Me5; X=Cl, Br, Me) with LiEH4 (E=Al, B) or BH3(thf), and their structures elucidated by experimental and theoretical methods. The treatment of trihalides [TiCp*X3] with LiAlH4 in ethereal solvents (L) leads to the hydride‐bridged heterometallic complexes [{TiCp*(μ‐H)}2{(μ‐H)2AlX(L)}2] (L=thf, X=Cl, Br; L=OEt2, X=Cl). Density functional theory (DFT) calculations for those compounds reveal an open‐shell singlet ground state with a Ti−Ti bond and can be described as titanium(II) species. The theoretical analyses also show strong interactions between the Ti−Ti bond and the empty s orbitals of the Al atom of the AlH2XL fragments, which behave as σ‐accepting (Z‐type) ligands. Analogous reactions of [TiCp*X3] with LiBH4 (2 and 3 equiv.) in tetrahydrofuran at room temperature and at 85 °C lead to the titanium(III) compounds [{TiCp*(BH4)(μ‐X)}2] (X=Cl, Br) and [{TiCp*(BH4)(μ‐BH4)}2], respectively. The treatment of [TiCp*Me3] with 4 and 5 equiv. of BH3(thf) produces the diamagnetic [{TiCp*(BH3Me)}2(μ‐B2H6)] and paramagnetic [{TiCp*(μ‐B2H6)}2] complexes, respectively.
Diastereoselective Alkene Hydroesterification Enabling the Synthesis of Chiral Fused Bicyclic Lactones
Authors: Shi Zhanglin , Shen Chaoren , Dong Kaiwu
Published: November 2021

Palladium‐catalysed diastereoselective hydroesterification of alkenes assisted by the coordinative hydroxyl group in the substrate afforded a variety of chiral γ‐butyrolactones bearing two stereocenters. Employing the carbonylation‐lactonization products as the key intermediates, the route from the alkenes with single chiral center to chiral THF‐fused bicyclic γ‐lactones containing three stereocenters was developed.
Racemization mechanism of lithium tert‐butylphenylphosphido‐borane: A kinetic insight
Authors: Fortrie Rémy , Gatineau David , Hérault Damien , Béal Aurélie , Naubron Jean‐Valère , Giordano Laurent , Buono Gérard
Published: November 2021

The racemization mechanism of tert‐butylphenylphosphido‐borane is investigated experimentally and theoretically. Based on this converging approach, it is shown, first, that several phosphido‐borane molecular species coexist at the time of the reaction and, second, that one particular of both initially assumed reactive routes most significantly contribute to the overall racemization process. From our converging modeling and experimental measurement, it comes out that the most probable species to be here encountered is a phosphido‐borane‐Li (THF)2 neutral solvate, whose P‐stereogenic center monomolecular inversion through a Y‐shaped transition structure (ΔrG°≠: 81 kJ mol−1) brings the largest contribution to the racemization process.
Temperature and Composition Dependent Optical Properties of CdSe/CdS Dot/Rod‐Based Aerogel Networks
Authors: Rusch Pascal , Pluta Denis , Lübkemann Franziska , Dorfs Dirk , Zámbó Dániel , Bigall Nadja C.
Published: November 2021

Employing nanocrystals (NCs) as building blocks of porous aerogel network structures allows the conversion of NC materials into macroscopic solid structures while conserving their unique nanoscopic properties. Understanding the interplay of the network formation and its influence on these properties like size‐dependent emission is a key to apply techniques for the fabrication of novel nanocrystal aerogels. In this work, CdSe/CdS dot/rod NCs possessing two different CdSe core sizes were synthesized and converted into porous aerogel network structures. Temperature‐dependent steady‐state and time‐resolved photoluminescence measurements were performed to expand the understanding of the optical and electronic properties of these network structures generated from these two different building blocks and correlate their optical with the structural properties. These investigations reveal the influence of network formation and aerogel production on the network‐forming nanocrystals. Based on the two investigated NC building blocks and their aerogel networks, mixed network structures with various ratios of the two building blocks were produced and likewise optically characterized. Since the different building blocks show diverse optical response, this technique presents a straightforward way to color‐tune the resulting networks simply by choosing the building block ratio in connection with their quantum yield.
Information seeking and health anxiety during the COVID‐19 pandemic: The mediating role of catastrophic cognitions
Authors: Jagtap Shreya , Shamblaw Amanda L. , Rumas Rachel , Best Michael W.
Published: November 2021

Cognitive–behavioural models of health anxiety propose a positive association between information seeking and health anxiety; however, it is unclear the extent to which cognitive mechanisms may mediate this relationship. Catastrophic cognitions are one type of cognition that may mediate this relationship, and the COVID‐19 pandemic has presented an opportunity to examine these relationships within the context of a global health catastrophe. The current study investigated both cross‐sectional (N = 797) and longitudinal (n = 395) relationships between information seeking, health anxiety and catastrophizing during the pandemic. Data were collected using Amazon Mechanical Turk during April and May 2020. Information seeking and health anxiety were positively associated both cross‐sectionally and longitudinally (rs = .25–.29). Catastrophic cognitions significantly mediated the relationship between information seeking and health anxiety both cross‐sectionally and longitudinally. Developing effective methods of reducing information seeking and catastrophizing may serve to reduce health anxiety during global health crises such as the current pandemic.
Therapeutic targeting of SPIB/SPI1‐facilitated interplay of cancer cells and neutrophils inhibits aerobic glycolysis and cancer progression
Authors: Wang Jianqun , Wang Xiaojing , Guo Yanhua , Ye Lin , Li Dan , Hu Anpei , Cai Shuang , Yuan Boling , Jin Shikai , Zhou Yi , Li Qilan , Zheng Liduan , Tong Qiangsong
Published: November 2021

Background

As a metabolic reprogramming feature, cancer cells derive most of their energy from aerobic glycolysis, while its regulatory mechanisms and therapeutic strategies continue to be illusive.

Methods

Integrative analysis of publically available expression profile datasets was used to identify critical transcriptional regulators and their target glycolytic enzymes. The functions and acting mechanisms of transcriptional regulators in cancer cells were investigated by using in vitro and in vivo assays. The Kaplan–Meier curve and log‐rank assay were used to conduct the survival study.

Results

Salmonella pathogenicity island 1 (SPI1/PU.1), a haematopoietic transcription factor, was identified to facilitate glycolytic process, tumourigenesis, invasiveness, as well as metastasis of colon cancer cells, which was interplayed by tumour‐associated neutrophils. Mechanistically, neutrophils delivered SPI1 mRNA via extracellular vesicles, resulting in enhanced SPI1 expression of cancer cells. Through physical interaction with SPI1‐related protein (SPIB), SPI1 drove expression of glycolytic genes within cancer cells, which in turn induced polarization of neutrophils via glycolytic metabolite lactate. Depletion of neutrophils or SPIB–SPI1 interaction in cancer cells significantly inhibited glycolytic process, tumourigenesis and aggressiveness. Upregulation of SPI1 or SPIB was found to be associated with poor prognosis in patients suffering from colon cancer.

Conclusions

Therapeutic targeting of SPIB/SPI1‐facilitated interplay of cancerous cells and neutrophils suppresses aerobic glycolysis and progression of cancer.
An efficient three‐factor user authentication scheme for industrial wireless sensor network with fog computing
Authors: Sahoo Shreeya Swagatika , Mohanty Sujata , Majhi Banshidhar
Published: November 2021

User authentication in industrial wireless sensor network (IWSN) is a security issue due to the hostile deployment of sensors in the field. The generated data from these sensors are generally processed in a cloud environment to provide on‐demand services. However, cloud computing suffers from several issues such as transmission latency and response time, and fog computing is hence introduced to resolve these issues. In the fog environment, the fog devices are placed near the user and responsible for intermediate computation and storage. This paper proposes a three‐factor‐based user authentication scheme for IWSN using fog computing (UASFI). The proposed scheme supports dynamic sensor node addition and smart card revocation phase. We employed the real‐or‐random (ROR) model for formal security analysis, which demonstrates the secrecy of the session key during communication. Furthermore, the simulation using NS2 and the comparison with existing schemes in terms of communicational and storage cost show that the proposed scheme is efficient for practical use.
Life impact of VA‐ECMO due to primary graft dysfunction in patients after orthotopic heart transplantation
Authors: M'Pembele René , Roth Sebastian , Stroda Alexandra , Buse Giovanna Lurati , Sixt Stephan U. , Westenfeld Ralf , Polzin Amin , Rellecke Philipp , Tudorache Igor , Hollmann Markus W. , Aubin Hug , Akhyari Payam , Lichtenberg Artur , Huhn Ragnar , Boeken Udo
Published: November 2021

Aims

Primary graft dysfunction (PGD) is a feared complication after heart transplantation (HTX). HTX patients frequently receive veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) until graft recovery. Long‐term mortality of patients weaned from VA‐ECMO after HTX is comparable with non‐ECMO patients. However, impact on quality of life is unknown. This study investigated days alive and out of hospital (DAOH) as patient‐centred outcome in HTX patients at 1 year after surgery.

Methods and results

This retrospective single‐centre cohort study included patients who underwent HTX at the University Hospital Düsseldorf, Germany, from 2010 to 2020. Main exposure was VA‐ECMO due to PGD. VA‐ECMO and non‐VA‐ECMO patients were compared regarding the primary endpoint DAOH at 1 year after HTX. Subgroup analysis for patients weaned from VA‐ECMO was performed. In total, 144 patients were included into analysis; 1 year mortality was significantly lower in non‐ECMO patients [non‐ECMO 14.3% (14/98) vs. VA‐ECMO 34.8% (16/46), adjusted hazard ratio: 0.32, 95% confidence interval: 0.15–0.74; P = 0.002]. Mortality did not differ significantly between patients weaned from VA‐ECMO and non‐ECMO patients [non‐ECMO 14.3% (14/98) vs. VA‐ECMO (weaned) 18.9% (7/37), adjusted hazard ratio: 0.72, 95% confidence interval: 0.27–1.90; P = 0.48]. DAOH were significantly higher in non‐ECMO patients compared with VA‐ECMO patients and patients weaned from VA‐ECMO [non‐ECMO vs. VA‐ECMO: median 310 (inter‐quartile range 277–327) days vs. 243 (0–288) days; P < 0.0001; non‐ECMO vs. VA‐ECMO (weaned): 310 (277–327) days vs. 253 (208–299) days; P < 0.0001]. These results were still significant after multivariable adjustment with forced entry of predefined covariables.

Conclusions

Despite similar survival rates, VA‐ECMO due to PGD has a relevant life impact as defined by DAOH in the first year after HTX. As a more patient‐centred endpoint, DAOH may contribute to a more comprehensive assessment of outcome in HTX patients.
Mixed RuIIComplexes Containing Diseleno‐Ligand and α,β‐Diketones Donors with Anticancer Activity. Synthesis, Characterization, Electrochemical and DFT Studies
Authors: Hernández‐Ayala Luis Felipe , Novoa‐Ramírez Cynthia Sinaí , Reina Miguel , Ruiz‐Azuara Lena
Published: November 2021

This work presents the synthesis, characterization, electrochemical studies, DFT calculations and in vitro evaluation of antiproliferative activity in HeLa cells of four novel direct bonded ruthenium‐selenium compounds. The complexes are [Ru(BP3Se2)Cl(PPh3)]Cl(1)and mixed [Ru(BP3Se2)(O−O)(PPh3)]Cl (2 a,2 b,2 c) systems with diseleno‐ligandBP3Se2: 1,9‐bis(2‐pyridyl)‐3,7‐diselenanonane as a primary donor and O−O: α,β‐diketones as a secondary donors. In1,BP3Se2is linked in tetradentate N2Se2form while in mixed complexes, present a tridentate NSe2linkage. Diketone nature and electroactive groups has a fundamental role in the modulation of the electronic, steric and lipophilic properties as well as in its cytotoxic activity. Among the tested compounds,2 chas the best cytotoxic performance (IC50=2.8 μmol/L) even higher than metallodrug cisplatin. In this regard, cytotoxic activity is strongly determined by experimental redox potential (E0) and calculated molar volume (VM) of the compounds.
Borrowing Hydrogen and Acceptorless Dehydrogenative Coupling in the Multicomponent Synthesis of N‐Heterocycles: A Comparison between Base and Noble Metal Catalysis
Authors: Hofmann Natalie , Hultzsch Kai C.
Published: November 2021

Acceptorless dehydrogenative coupling reactions (ADC) and hydrogen transfer strategies (HT) provide a powerful tool in the multicomponent formation of N‐heterocycles. A broad variety of complex products can be obtained starting from simple, cheap and commercially available reagents. The protocols are highly atom‐efficient, as water, dihydrogen, or in some cases hydrogen peroxide, are the only by‐products. Moreover, neither further reducing or oxidizing agents, nor external hydrogen are in general required. Especially base metal‐catalyzed strategies become ever more important. Therefore, in recent years, various different manganese, iron, cobalt, nickel and copper catalysts have been developed. This Minireview highlights the progress that has been made by using abundant metal complexes to promote multicomponent cyclizations for the formation of N‐heterocycles and compares their performance with available noble metal catalyst systems.
Geochemistry and zircon U–Pb dating of Early Jurassic syenogranite in the Kaoshan area, southern part of the Zhangguangcai Range, NE China, and tectonic implications
Authors: Ye Xiqing , Sun Liying , Xu Zhitao , Yan Donghan , Yang Qingfu , Zhu Daqing , Feng Jingqiao , Chen Linrong
Published: November 2021

Early Jurassic Kaoshan medium‐ and fine‐grained syenogranites emplaced along the Yitong–Shulan Fault Zone in the southern part the Zhangguangcai Range, central Jilin Province, intruded Middle Triassic granitoids and Carboniferous‐Devonian intrusive rocks. They have medium‐ and fine‐grained textures and contain K‐feldspar, quartz, plagioclase, and biotite. They are peraluminous (A/CNK = 1.13–1.20) and have high values of SiO2 (74.60–75.82 wt%), total alkalis (Na2O + K2O = 8.28–9.18 wt%), light rare earth elements (20.89–56.14 ppm), large‐ion lithophile elements, and FeO/MgO = 2.78–5.93. In contrast, they feature low values of CaO (0.40–0.49 wt%), TiO2 (0.05–0.14 wt%), P2O5 (0.02–0.04 wt%), Sr (24.20–62.59 ppm), heavy rare earth elements (5.14–11.80 ppm), high‐field‐strength elements, and δEu (0.41–0.76), and the calculated zircon saturation temperatures (Tzr) range from 804 to 870°C, all of which are similar to the geochemical signatures of anorogenic A1‐type granites. Zircon U–Pb geochronology analyses from the medium‐ and fine‐grained syenogranites yield concordia ages of 193.18 ± 0.95 Ma (MSWD = 6.7, n = 18) and 190.29 ± 0.92 Ma (MSWD = 8.7, n = 17), respectively, and belong to the Early Jurassic Sinemurian stage. In situ Hf isotope analyses of dated zircons yield εHf(t) values ranging from +17.0 to +9.7 and Hf model ages (TDMC) of 225–614 Ma. Their whole‐rock (87Sr/86Sr)i (0.704740–0.704133) and εNd(t) values (+2.8 to +0.2) are similar to those of many coeval A2‐type granites in this region, and they form an A‐type granite assemblage. Consequently, the Kaoshan medium‐ and fine‐grained syenogranites were probably derived from partial melting of juvenile lower crust and might be related to the subduction of the Palaeo‐Pacific Plate.
Improving youth physical, mental and social health through physical activity: A Systematic literature review
Authors: Kemel Paul N. , Porter Joanne E. , Coombs Nicole
Published: November 2021

Background

Across various parts of the world there is an increasing trend in adolescent and young adult physical inactivity, which has been linked to a multitude of illnesses throughout the lifespan. To further understand the link between physical inactivity and illness, it is important to determine the effect that physical activity has various components of wellbeing. The primary aim of this review was to compile and synthesise the recent evidence on physical activity and its effect on physical, mental and social wellbeing across younger populations. The secondary aim was to determine whether there is relationship between the amount, type and intensity of exercise, and changes in wellbeing outcomes.

Methods

Main databases were searched using MeSH terms for the population of interest (young adult, adolescent), intervention (physical activity) and outcome (wellbeing). Upon screening papers of eligibility, quality appraisal was completed through the Critical Appraisals Skills Programme (CASP).

Results

Nineteen studies were included in this review. The majority of studies found an associated link between the participation of physical activity and improvements in physical, mental and social wellbeing outcomes. There was evidence to suggest that lower levels of physical intensity produced similar results in mental and social outcomes when compared to higher levels of physical intensity.

Conclusion

This review supports the encouragement of adolescent and young adult physical activity, noting the improvements seen across the physical, mental and social wellbeing outcomes. Future research is still required to further understand the benefits of lower intensity exercise within the adolescent and young adult population.
Development and application of quality measures of clinical pharmacist services provided in inpatient/acute care settings
Authors: Acquisto Nicole M. , Beavers Craig J. , Bolesta Scott , Buckley Mitchell S. , Dobbins Kelsey F. , Finch Christopher K. , Hayes Sarah M. , Holdren Danielle B. , Johnson Steven T. , Kane‐Gill Sandra L. , Lat Ishaq
Published: November 2021

As health care transitions to value‐based care, it is more critical than ever to emphasize and quantify the impact on patient outcomes made by inpatient/acute care pharmacists and pharmacist extenders as members of the interprofessional care team. Thus, the American College of Clinical Pharmacy (ACCP) took to task the development of quality measures that were broadly applicable to the diverse inpatient/acute care landscape and important for standardizing practice, measuring impact, contextualizing benefit within the health care landscape, and allowing benchmarking within and between institutions. A framework was established by the writing committee of this paper in order to develop quality measures in a methodical manner. The resulting process led the writing committee to devise 31 foundational quality measures to be used in efforts to champion the pharmacist's role in achieving the quadruple aims in health care. Application and evaluation of quality measure performance as well as limitations and future implications of the measures are addressed to further highlight the evolving role of the inpatient/acute care pharmacist and pharmacist extender.
Psychopathic dispositions and emotion dysregulation: A dual‐disposition model perspective
Authors: Guo Peiyang , Wang Mengya , Cheng Cheng , Chen Hao
Published: November 2021

The Dual‐Disposition Model proposes to understand psychopathy through two dispositions (i.e., threat sensitivity and poor inhibitory control) with distinct etiological substrates. In the current study, we examined the predictive contributions of threat sensitivity, poor inhibitory control, and their interaction to emotion dysregulation in 694 Chinese undergraduates based on the Disinhibition subscale of Triarchic Psychopathy Measure, Behavioral Inhibition System Scale, and Difficulties in Emotion Regulation Scale. Our results suggested that two dispositions have independent contributions to emotion dysregulation. Additionally, interactive effects of two dispositions were found for emotion awareness, impulse control, emotional acceptance, and limited emotion regulation strategies when upset. These provide evidence that deficits associated with poor inhibitory control can be selectively suppressed by low threat sensitivity or exacerbated by high threat sensitivity. Training individuals with high psychopathic dispositions to focus on their emotional state might be able to enhance their ability of emotion regulation.
(Not) minding the gap: A qualitative interview study of how social class bias can influence youth mentoring relationships
Authors: Spencer Renée , McCormack Martha J. , Drew Alison L. , Gowdy Grace , Keller Thomas E.
Published: November 2021

This study sought to examine how social class bias may be enacted by mentors and mentoring program staff within community‐based youth mentoring relationships and how these biases may influence the mentoring relationship. A narrative thematic analysis was conducted with interviews from mentors, mentees’ parents/caregivers, and mentoring program staff representing 36 matches participating in a larger, prospective, mixed‐methods study examining factors associated with early match closures. Findings indicate that although some mentors were able to partner with the youth and family to effectively navigate challenges related to the family's economic circumstances, other mentors and some mentoring program staff held deficit views of the youth and their family that appeared to be at least partially rooted in negative social class‐based assumptions about attitudes and behaviors. Specifically, we observed tendencies on the part of some mentors and program staff toward (a) deficit‐based views of families and youth, (b) individual‐level attributions for the family's economic circumstances and blaming of caregivers, and (c) perceiving mentors as being underappreciated by the youth's caregiver. These deficit perspectives contributed to the minimization of parent/caregiver voice in the mentoring process and negative interpretations of parent/caregiver and, in some cases, youth attitudes and behaviors.
Preparing for the 2070s: Reflections from the Journal of Community Psychology's initial decade: Pathways to Community Psychology's continuing maturation
Authors: Lorion Raymond P.
Published: November 2021

This commentary introduces a virtual monograph that celebrates the 50th anniversary of the Journal of Community Psychology. The commentary focuses on originating goals of the discipline and pathways taken in their pursuit and change. The monograph challenges current leaders to define pathways for the next 50 years.
The link between food insecurity and psychological distress: The role of stress exposure and coping resources
Authors: Ciciurkaite Gabriele , Brown Robyn Lewis
Published: November 2021

This study examines the association between food insecurity and mental health over a 3‐year period. It also assesses the salience of life stressors and psychosocial coping resources for this association. We utilize data from a two‐wave community survey of Miami‐Dade County, Florida residents (N = 1488). Findings from SEM analysis reveal that greater food insecurity at W1 is associated with greater depressive symptoms at W2, lending credence to characterizations of food insecurity as a chronic stressor. This association is partly mediated by variation over the study period in social support and mastery. However, no significant mediating effects are observed for the social stress indicators assessed. Food insecurity is associated with diminished psychosocial coping resources, which leads to greater psychological distress. We discuss how these findings extend a stress and coping model of food insecurity, and implications for research and practice.
The effect of social support on work stress in health workers during the pandemic: The mediation role of resilience
Authors: Karadaş Ayşe , Duran Songül
Published: November 2021

Stressful experiences commonly increase among health workers during the coronavirus disease 2019 (COVID‐19) pandemic. From this perspective, this study primarily aimed to examine the mediating role of resilience in the effect of perceived social support on work stress among health workers. The sample of the study consisted of 402 health workers. In the research, the “General Work Stress Scale,” “Brief Resiliency Scale,” and “Multidimensional Scale of Perceived Social Support” were used. There was a statistically significant negative correlation between work stress and social support (r = −0.223, p = 0.00) and resilience (r = −0.432, p = 0.00), and a statistically significant positive correlation between social support and resilience (r = 0.226, p = 0.00). Resilience mediates the relationship between perception of social support and work stress. When planning effective intervention strategies, it will be critical to reduce the risk of adverse mental health outcomes in health workers, who are fighting against the COVID‐19 pandemic, by increasing social support and resilience and reducing work stress.
Anterior‐posterior patterning of segments in Anopheles stephensi offers insights into the transition from sequential to simultaneous segmentation in holometabolous insects
Authors: Cheatle Jarvela Alys M. , Trelstad Catherine S. , Pick Leslie
Published: November 2021

The gene regulatory network for segmentation in arthropods offers valuable insights into how networks evolve owing to the breadth of species examined and the extremely detailed knowledge gained in the model organism Drosophila melanogaster. These studies have shown that Drosophila's network represents a derived state that acquired changes to accelerate segment patterning, whereas most insects specify segments gradually as the embryo elongates. Such heterochronic shifts in segmentation have potentially emerged multiple times within holometabolous insects, resulting in many mechanistic variants and difficulties in isolating underlying commonalities that permit such shifts. Recent studies identified regulatory genes that work as timing factors, coordinating gene expression transitions during segmentation. These studies predict that changes in timing factor deployment explain shifts in segment patterning relative to other developmental events. Here, we test this hypothesis by characterizing the temporal and spatial expression of the pair‐rule patterning genes in the malaria vector mosquito, Anopheles stephensi. This insect is a Dipteran (fly), like Drosophila, but represents an ancient divergence within this clade, offering a useful counterpart for evo‐devo studies. In mosquito embryos, we observe anterior to posterior sequential addition of stripes for many pair‐rule genes and a wave of broad timer gene expression across this axis. Segment polarity gene stripes are added sequentially in the wake of the timer gene wave and the full pattern is not complete until the embryo is fully elongated. This “progressive segmentation” mode in Anopheles displays commonalities with both Drosophila's rapid segmentation mechanism and sequential modes used by more distantly related insects.
Southern Baffin Island mean annual precipitation isotopes modulated by summer and autumn moisture source changes during the past 5800 years
Authors: Gorbey Devon B. , Thomas Elizabeth K. , Crump Sarah E. , Hollister Kayla V. , Raynolds Martha K. , Raberg Jonathan H. , de  Wet Gregory , Sepúlveda Julio , Miller Gifford H.
Published: November 2021

Paleo water isotope records can elucidate how the Arctic water cycle responded to past climate changes. We analyze the hydrogen isotope composition (δ2H) of plant‐derived n‐alkanoic acids (waxes) from Lake Qaupat, Baffin Island, Nunavut, Canada, to assess moisture sources and seasonality during the past 5.8 ka. We compare this record to a sedimentary ancient DNA (sedaDNA)‐inferred vascular plant record from the same lake, aiming to overcome the uncertainty of plant community impacts on leaf waxes. As the sedaDNA record reveals a stable plant community after the colonization of Betula sp. at 6.1 ka, we interpret plant wax δ2H values to reflect climate, specifically mean annual precipitation δ2H. However, the distributions of n‐alkanoic acid homologs suggest that aquatic mosses, which are not represented in the sedaDNA record, may become more abundant towards the present. Therefore, we cannot exclude the possibility that changes in the plant community cause changes in the plant wax δ2H record, particularly long‐chain waxes, which become less abundant through this record. We find that Lake Qaupat mid‐chain plant wax δ2H is enriched coincident with high Labrador Sea summer surface temperature, which suggests that local moisture sources in summer and early autumn have the greatest impact on precipitation isotopes in this region.
Balancing reality in embedded research and evaluation: Low vs high embeddedness
Authors: Jackson George L. , Damschroder Laura J. , White Brandolyn S. , Henderson Blake , Vega Ryan J. , Kilbourne Amy M. , Cutrona Sarah L.
Published: November 2021

Embedding research and evaluation into organizations is one way to generate “practice‐based” evidence needed to accelerate implementation of evidence‐based innovations within learning health systems. Organizations and researchers/evaluators vary greatly in how they structure and operationalize these collaborations. One key aspect is the degree of embeddedness: from low embeddedness where researchers/evaluators are located outside organizations (eg, outside evaluation consultants) to high embeddedness where researchers/evaluators are employed by organizations and thus more deeply involved in program evolution and operations. Pros and cons related to the degree of embeddedness (low vs high) must be balanced when developing these relationships. We reflect on this process within the context of an embedded, mixed‐methods evaluation of the Veterans Health Administration (VHA) Diffusion of Excellence (DoE) program. Considerations that must be balanced include: (a) low vs high alignment of goals; (b) low vs high involvement in strategic planning; (c) observing what is happening vs being integrally involved with programmatic activities; (d) reporting findings at the project's end vs providing iterative findings and recommendations that contribute to program evolution; and (e) adhering to predetermined aims vs adapting aims in response to evolving partner needs.
Organic/Inorganic Self‐Assembled Hybrid Nano‐Architectures for Cancer Therapy Applications
Authors: Yang Chengbin , Lin Zheng‐Ian , Chen Jian‐An , Xu Zhourui , Gu Jiayu , Law Wing‐Cheung , Yang Jason Hsiao Chun , Chen Chih‐Kuang
Published: November 2021

Since the conceptualization of nanomedicine, numerous nanostructure‐mediated drug formulations have progressed into clinical trials for treating cancer. However, recent clinical trial results indicate such kind of drug formulations has a limited improvement on the antitumor efficacy. This is due to the biological barriers associated with those formulations, for example, circulation stability, extravasation efficiency in tumor, tumor penetration ability, and developed multi‐drug resistance. When employing for nanomedicine formulations, pristine organic‐based and inorganic‐based nanostructures have their own limitations. Accordingly, organic/inorganic (O/I) hybrids have been developed to integrate the merits of both, and to minimize their intrinsic drawbacks. In this context, the recent development in O/I hybrids resulting from a self‐assembly strategy will be introduced. Through such a strategy, organic and inorganic building blocks can be self‐assembled via either chemical covalent bonds or physical interactions. Based on the self‐assemble procedure, the hybridization of four organic building blocks including liposomes, micelles, dendrimers, and polymeric nanocapsules with five functional inorganic nanoparticles comprising gold nanostructures, magnetic nanoparticles, carbon‐based materials, quantum dots, and silica nanoparticles will be highlighted. The recent progress of these O/I hybrids in advanced modalities for combating cancer, such as, therapeutic agent delivery, photothermal therapy, photodynamic therapy, and immunotherapy will be systematically reviewed.
Significant Performance Improvement of Thermoplastic Polyurethane Composites by Multiple Effects of Monodispersed Graphene: Micro‐Crosslinking, Isolation, and Induced Crystallization
Authors: Yang Lide , Lou Jiankun , Yuan Jianmin , Deng Jianru
Published: November 2021

Thermoplastic polyurethane composites (TPCs) in kilogram scale reinforced with monodispersed functionalized graphene (FGr) are prepared by melt‐blending on industrial extruder and their properties are studied in this work. It shows that the saturation content of monodispersed FGr in TPCs is ≈0.5 wt%, beyond which part of it will agglomerate. The multiple effects of monodispersed FGr—micro‐crosslinking, isolation, and induced crystallization—have great impact on the properties of TPCs. With the content increase of FGr, the melt rheological properties, crystallization properties, mechanical properties, and shape memory properties of TPCs show regular changes. More importantly, the tensile fracture behaviors of TPCs are dramatically changed by FGr. Some microfibers with high strength are formed and lay astride the cracks to prevent crack propagation during the damage process. Therefore, the tensile strength of TPC with 0.5 wt% FGr is maximumly improved, showing an increase of 139% compared to neat thermoplastic polyurethane. Its shape fixed ratio and shape recovery ratio are respectively raised to 96% and 94%, showing a good shape memory performance.
Explicit, determinantal, recursive formulas and relations of the Peters polynomials and numbers
Authors: Dağlı Muhammet Cihat
Published: November 2021

In this paper, with the help of the Faà di Bruno formula and an identity for the Bell polynomials of the second kind, we find several explicit formulas for the Peters polynomials and numbers. Also, we present determinantal representations for the Peters polynomials and numbers by virtue of a general derivative formula for the ratio of two differentiable functions. Moreover, we give several recursive relations for the Peters polynomials and numbers. As an application, we establish alternative recursive relations for them with the aid of a recursive relation for the Hessenberg determinants. These results cover counterparts for the Boole polynomials and numbers.
Bladder surface dose modeling in prostate cancer radiotherapy: An analysis of motion‐induced variations and the cumulative dose across the treatment
Authors: Lao Yi , Cao Minsong , Yang Yingli , Kishan Amar U. , Yang Wensha , Wang Yalin , Sheng Ke
Published: November 2021

Purpose

To introduce a novel surface‐based dose mapping method to improve quantitative bladder dosimetric assessment in prostate cancer (PC) radiotherapy.

Methods

Based on the planning and daily pre and postfraction MRIs of 12 PC patients, bladder surface models (SMs) were generated on manually delineated contours and regionally aligned via surface‐based registration. Subsequently, bladder surface dose models (SDMs) were created using face‐wise dose sampling. To determine the bladder intrafractional and interfractional motion and dose variation, we performed a pose analysis between pre and postfraction bladder SMs, as well as surface mapping for fractional SMs. Discrepancies between the received dose, accumulated from daily SDMs, and the planned dose were then assessed on the corresponding SDMs. Complementary to the surface dose mapping, dose surface histogram (DSH)‐based comparisons were also performed.

Results

The intrafraction pose analysis revealed a significant (p < 0.05) bladder expansion, as well as an anterior/superior drift during the treatment. The intrafraction motion substantially altered dose to mid‐bladder body, but not the bladder surface areas distal to or contiguous with the target. A similar pattern of dose variations was also detected by interfraction comparisons. With surface registration to the common SM, the cumulative bladder dose significantly differs from the planned dose. The discrepancy is evident in the mid‐posterior range that corresponds to a mid‐ to high‐dose region. The received DSH significantly differs from the planned DSH after permutation correction (p = 0.0122), while the overall surface‐based comparison after multiple comparison correction is nonsignificant (p = 0.0800).

Conclusions

We developed a novel surface‐based intra and interdose mapping framework applied to a unique daily MR dataset for image‐guided radiotherapy. The framework identified significant intrafraction bladder positional changes, localized the intra and interfraction variations, and quantified planned versus received dose differences on the bladder surface. The result indicates the importance of adopting the motion‐integrated bladder SDM for bladder dose management.
Waitlist mortality and post‐liver transplant outcomes of pediatric patients with hepatocellular carcinoma and hepatoblastoma in the United States
Authors: Wu W. Kelly , Ziogas Ioannis A. , Matsuoka Lea K. , Izzy Manhal , Pai Anita K. , Benedetti Daniel J. , Alexopoulos Sophoclis P.
Published: November 2021

Background

Liver transplantation (LT) is offered in cases of advanced disease for both pediatric patients with hepatoblastoma (HBL) and those with hepatocellular carcinoma (HCC). Current United States organ allocation priorities differ between the two groups.

Methods

We retrospectively examined the waitlist and posttransplant outcomes of pediatric LT candidates with HBL and HCC using the United Network for Organ Sharing registry (February 2002 to September 2020).

Results

Six hundred sixty‐eight children with HBL and 95 children with HCC listed for first LT were identified. Patients with HBL were younger (p < .001), had lower laboratory Model for End‐stage Liver Disease (MELD)/Pediatric End‐stage Liver Disease (PELD) scores (p < .001), and had lesser proportion with encephalopathy (p = .01). Patients with HCC had an increased risk of waitlist mortality in univariable (unadjusted subdistribution hazard ratio [sHR] = 4.37, 95% confidence interval [CI], 2.01–9.51, p < .001) and multivariable competing risk regression (adjusted sHR = 3.08, 95% CI 1.13–8.37, p = .03) accounting for age and laboratory MELD/PELD score. Five hundred ninety‐five children underwent LT for HBL and 76 for HCC. Patients transplanted for HBL had a significantly higher proportion with status 1B exception (71.3% vs. 7.9%, p < .001). No difference was observed in patient (unadjusted log‐rank test, p = .52; adjusted hazard ratio [HR] = 0.77, 95% CI, 0.40–1.48, p = .43) or graft survival (unadjusted log‐rank test, p = .93; adjusted HR = 0.74, 95% CI 0.42–1.33, p = .32) between HCC and HBL recipients.

Conclusion

Waitlist mortality for pediatric LT candidates with HCC is significantly higher than for HBL, while posttransplant patient and graft survival are similar. This highlights an opportunity to improve equitable prioritization for children with HCC who may have reduced access to size‐appropriate deceased donor organs and less effective bridge‐to‐transplant therapies.
An experimental investigation of epoxy‐based hybrid composites with hexagonal boron nitride and short sisal fiber as reinforcement for high performance microelectronic applications
Authors: Agrawal Alok , Chandraker Saurabh
Published: November 2021

In the present article, an investigation is presented on epoxy‐based composites where the discontinuous phases are microsized boron nitride and sisal fiber (SF). Both the reinforcing materials are surface modified before incorporating them into the epoxy matrix. Hexagonal boron nitride (hBN) surface is treated by silane‐coupling agent, whereas the aqueous NaOH solution is used to modify the surface of SF. The effect of fillers on the physical, mechanical, thermal, and dielectric properties of hybrid composites is studied through experimentation. The result shows that the inclusion of hBN increases the thermal conductivity of epoxy appreciably and dielectric constant marginally, while the inclusion of SF reduces the thermal conductivity marginally and dielectric constant appreciably. The maximum thermal conductivity of 1.88 W/m‐K is obtained for the combination of 30 wt% hBN and 3 wt% SF. For the same combination, the dielectric constant is 4.57 at 1 GHz, which is almost similar to neat epoxy. Also, other properties like compressive strength, hardness, glass‐transition temperature, and coefficient of thermal expansion improve when combinations of ceramic filler and natural fiber were incorporated in the epoxy matrix. Due to outstanding comprehensive properties, epoxy/hBN/SF composites found potential application in wide microelectronic applications.
Effect of strain rate on the mechanical properties of polycarbonate processed by compression and injection molding
Authors: Ullrich Fabian , Singh Shailendra Pal Veer , McDonald Sean , Krueger Alex , Vera‐Sorroche Javier , Amirkhizi Alireza , Masato Davide
Published: November 2021

The high impact strength of polycarbonate has been studied and exploited for many applications. However, the interaction between processing‐induced effects and the strain rate affects the mechanical behavior significantly. In this work, the effects of the processing‐induced thermal history, generated by either injection molding or compression molding, were characterized. Polycarbonate samples manufactured with the two processes were experimentally compared using quasi‐static and dynamic compression testing. The processing effects are further evaluated by combining a numerical calculation of the temperature history and a constitutive model to predict the yield strength of the glassy polymer. The constitutive modeling approach considers both the effect of the rate‐dependent and stress‐activated motion of the chain segments, and the strain‐hardening effect due to molecular alignment. The results indicate that the thermal history has a significant effect at low strain rates, while its influence is negligible in the dynamic range. The modeling effort allows estimating the yield strength with different accuracy depending on the strain rate values.
The Inventory of Teacher‐Student Relationships: Factor structure and associations with school engagement among high‐risk youth
Authors: Pham Yen K. , Murray Christopher , Gau Jeff
Published: November 2021

Teacher–student relationships have been studied with increasing intensity during the past three decades, but the majority of this study has focused on young children and has relied on teacher perceptions of these relationships. The current study was designed to add to this growing body of research by exploring the factor structure, reliability, and validity of an instrument designed to measure adolescents' perceptions of their own relationships with teachers. Participants included 687 high school students, half of whom were students with diagnosed disabilities and the other half were students considered at risk of academic failure due to placement in dropout retrieval programs. All youth completed a self‐report instrument of teacher–student relationships along with multidimensional measures of school engagement. Findings from a confirmatory factor analysis of the Inventory of Teacher–Student Relationships indicated that the three hypothesized factors (i.e., Communication, Trust, and Alienation) had robust factor loadings, adequate internal consistency, and were associated with multiple measures of school engagement. These findings align with previous research linking teacher–student relationships with school engagement and support the need for continued research on the importance of teacher–student relationships among adolescents who are at‐risk of experiencing difficulties in school.
CTD of SARS‐CoV‐2 N protein is a cryptic domain for binding ATP and nucleic acid that interplay in modulating phase separation
Authors: Dang Mei , Song Jianxing
Published: November 2021

SARS‐CoV‐2 nucleocapsid (N) protein plays essential roles in many steps of the viral life cycle, thus representing a key drug target. N protein contains the folded N‐/C‐terminal domains (NTD/CTD) and three intrinsically disordered regions, while its functions including liquid–liquid phase separation (LLPS) depend on the capacity in binding various viral/host‐cell RNA/DNA of diverse sequences. Previously NTD was established to bind various RNA/DNA while CTD to dimerize/oligomerize for forming high‐order structures. By NMR, here for the first time we decrypt that CTD is not only capable of binding S2m, a specific probe derived from SARS‐CoV‐2 gRNA but with the affinity even higher than that of NTD. Very unexpectedly, ATP, the universal energy currency for all living cells with high cellular concentrations (2–16 mM), specifically binds CTD with Kd of 1.49 ± 0.28 mM. Strikingly, the ATP‐binding residues of NTD/CTD are identical in the SARS‐CoV‐2 variants while ATP and S2m interplay in binding NTD/CTD, as well as in modulating LLPS critical for the viral life cycle. Results together not only define CTD as a novel binding domain for ATP and nucleic acid, but enforce our previous proposal that ATP has been evolutionarily exploited by SARS‐CoV‐2 to complete its life cycle in the host cell. Most importantly, the unique ATP‐binding pockets on NTD/CTD may offer promising targets for design of specific anti‐SARS‐CoV‐2 molecules to fight the pandemic. Fundamentally, ATP emerges to act at mM as a cellular factor to control the interface between the host cell and virus lacking the ability to generate ATP.
Quantitative systems pharmacology: Landscape analysis of regulatory submissions to the US Food and Drug Administration
Authors: Bai Jane P. F. , Earp Justin C. , Florian Jeffry , Madabushi Rajanikanth , Strauss David G. , Wang Yaning , Zhu Hao
Published: November 2021

Quantitative systems pharmacology (QSP) has been proposed as a scientific domain that can enable efficient and informative drug development. During the past several years, there has been a notable increase in the number of regulatory submissions that contain QSP, including Investigational New Drug Applications (INDs), New Drug Applications (NDAs), and Biologics License Applications (BLAs) to the US Food and Drug Administration. However, there has been no comprehensive characterization of the nature of these regulatory submissions regarding model details and intended applications. To address this gap, a landscape analysis of all the QSP submissions as of December 2020 was conducted. This report summarizes the (1) yearly trend of submissions, (2) proportion of submissions between INDs and NDAs/BLAs, (3) percentage distribution along the stages of drug development, (4) percentage distribution across various therapeutic areas, and (5) nature of QSP applications. In brief, QSP is increasingly applied to model and simulate both drug effectiveness and safety throughout the drug development process across disease areas.