bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of the 2017 Kidney Allocation Policy Change on Simultaneous Liver‐Kidney Utilization and Outcomes
Authors: Samoylova Mariya L. , Wegermann Kara , Shaw Brian I. , Kesseli Samuel J. , Au Sandra , Park Christine , Halpern Samantha E. , Sanoff Scott , Barbas Andrew S. , Patel Yuval A. , Sudan Debra L. , Berg Carl , McElroy Lisa M.
Published: March 2021

Historically in the United States, kidneys for simultaneous liver‐kidney transplantation (SLKT) candidates were allocated with livers, prioritizing SLKT recipients over much of the kidney waiting list. A 2017 change in policy delineated renal function criteria for SLKT and implemented a safety net for kidney‐after‐liver transplantation. We compared the use and outcomes of SLKT and kidney‐after‐liver transplant with the 2017 policy. United Network for Organ Sharing Standard Transplant Analysis and Research files were used to identify adults who received liver transplantations (LT) from August 10, 2007 to August 10, 2012; from August 11, 2012 to August 10, 2017; and from August 11, 2017 to June 12, 2019. LT recipients with end‐stage renal disease (ESRD) were defined by dialysis requirement or estimated glomerular filtration rate <25. We evaluated outcomes and center‐level, regional, and national practice before and after the policy change. Nonparametric cumulative incidence of kidney‐after‐liver listing and transplant were modeled by era. A total of 6332 patients received SLKTs during the study period; fewer patients with glomerular filtration rate (GFR) ≥50 mL/min underwent SLKT over time (5.8%, 4.8%, 3.0%; P = 0.01 ). There was also less variability in GFR at transplant after policy implementation on center and regional levels. We then evaluated LT‐alone (LTA) recipients with ESRD (n = 5408 from 2012‐2017; n = 2321 after the policy). Listing for a kidney within a year of LT increased from 2.9% before the policy change to 8.8% after the policy change, and the rate of kidney transplantation within 1 year increased from 0.7% to 4% (P < 0.001). After the policy change, there was no difference in patient survival rates between SLKT and LTA among patients with ESRD. Implementation of the 2017 SLKT policy change resulted in reduced variability in SLKT recipient kidney function and increased access to deceased donor kidney transplantation for LTA recipients with kidney disease without negatively affecting outcomes.
Update of the CLRP eye plaque brachytherapy database for photon‐emitting sources
Authors: Safigholi Habib , Parsons Zack , Deering Stephen G. , Thomson Rowan M.
Published: March 2021

Purpose

To update and extend the Carleton Laboratory for Radiotherapy Physics (CLRP) Eye Plaque (EP) dosimetry database for low‐energy photon‐emitting brachytherapy sources using egs_brachy, an open‐source EGSnrc application. The previous database, CLRP_EPv1, contained datasets for the Collaborative Ocular Melanoma Study (COMS) plaques (10–22 mm diameter) with 103Pd or 125I seeds (BrachyDose‐computed, 2008). The new database, CLRP_EPv2, consists of newly calculated three‐dimensional (3D) dose distributions for 17 plaques [eight COMS, five Eckert & Ziegler BEBIG, and four others representative of models used worldwide] for 103Pd, 125I, and 131Cs seeds.

Acquisition and validation methods

Plaque models are developed with egs_brachy, based on published/manufacturer dimensions and material data. The BEBIG plaques (modeled for the first time) are identical in dimensions to COMS plaques but differ in elemental composition and/or density. Previously benchmarked seed models are used. Eye plaques and seeds are simulated at the center of full‐scatter water phantoms, scoring in (0.05 cm)3 voxels spanning the eye for scenarios: (a) “HOMO”: simulated TG43 conditions; (b) “HETERO”: eye plaques and seeds fully modeled; (c) “HETsi” (BEBIG only): one seed is active at a time with other seed geometries present but not emitting photons (inactive); summation over all seeds in a plaque then yields “HETsum” (includes interseed effects). For validation, doses are compared to those from CLRP_EPv1 and published data.

Data format and access

Data are available at https://physics.carleton.ca/clrp/eye_plaque_v2, http://doi.org/10.22215/clrp/EPv2. The data consist of 3D dose distributions (text‐based EGSnrc “3ddose” file format) and graphical presentations of the comparisons to previously published data.

Potential applications

The CLRP_EPv2 database provides accurate reference 3D dose distributions to advance ocular brachytherapy dose evaluations. The fully‐benchmarked eye plaque models will be freely distributed with egs_brachy, supporting adoption of model‐based dose evaluations as recommended by TG‐129, TG‐186, and TG‐221.
Low‐carbohydrate, high‐fat enteral formulas for managing glycemic control in patients who are critically ill: A review of the evidence
Authors: Burslem Ryan , Rigassio Radler Diane , Parker Anna , Zelig Rena
Published: March 2021

Hyperglycemia is associated with increased morbidity and mortality. Low‐carbohydrate, high‐fat (LCHF) enteral formulas are marketed to improve glycemic control; however, given the multifactorial mechanisms contributing to hyperglycemia in patients who are critically ill, the effect that LCHF formulas may have on improving glycemic control in this patient population is unclear. Current guidelines for the use of LCHF formulas among patients who are critically ill are limited by a lack of evidence. This review explores recent research published in the past 7 years to determine whether LCHF enteral formulas improve glycemic control compared with standard enteral formulas in patients who are critically ill. Four randomized controlled trials met the inclusion criteria for this review. Their results suggest that LCHF formulas may improve glycemic control in patients who are critically ill with diabetes mellitus and/or who are hyperglycemic. Further large‐scale randomized controlled trials are warranted to validate these findings among different subgroups of patients with critical illness. The potential benefits of LCHF formulas need to be weighed against specific limitations, including that LCHF formulas typically do not contain sufficient protein to meet the recommended needs of patients who are critically ill.
A cellular expression map of epidermal and subepidermal cell layer‐enriched transcription factor genes integrated with the regulatory network in Arabidopsis shoot apical meristem
Authors: Bhatia Shivani , Kumar Harish , Mahajan Monika , Yadav Sonal , Saini Prince , Yadav Shalini , Sahu Sangram Keshari , Sundaram Jayesh Kumar , Yadav Ram Kishor
Published: March 2021

Transcriptional control of gene expression is an exquisitely regulated process in both animals and plants. Transcription factors (TFs) and the regulatory networks that drive the expression of TF genes in epidermal and subepidermal cell layers in Arabidopsis are unexplored. Here, we identified 65 TF genes enriched in the epidermal and subepidermal cell layers of the shoot apical meristem (SAM). To determine the cell type specificity in different stages of Arabidopsis development, we made YFP based transcriptional fusion constructs by taking a 3‐kb upstream noncoding region above the translation start site. Here, we report that for ~52% (22/42) TF genes, we detected transcription activity. TF genes derived from epidermis show uniform expression in early embryo development; however, in the late globular stage, their transcription activity is suppressed in the inner cell layers. Expression patterns linked to subepidermal cell layer identity were apparent in the postembryonic development. Potential upstream regulators that could modulate the activity of epidermal and subepidermal cell layer‐enriched TF genes were identified using enhanced yeast‐one‐hybrid (eY1H) assay and validated. This study describes the activation of TF genes in epidermal and subepidermal cell layers in embryonic and postembryonic development of Arabidopsis shoot apex.
Estane‐Assisted Preparation of Submicron β‐Form HMX Particles through Antisolvent Crystallization
Authors: Kim Dong Woo , Kim Hyejoo , Huh Eugene , Park Sewon , Lee Chang Ha , Ahn Ik Sung , Koo Kee Kahb , Lee Keun Deuk
Published: March 2021

Octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) particles were prepared through solvent‐antisolvent crystallization at room temperature by using dimethyl sulfoxide and ethanol as a solvent and an antisolvent, respectively. Estane, which has been used as a polymer binder in polymer‐bound explosives, was added to retard nucleation and inhibit crystal growth. The particles were characterized using scanning electron microscopy, X‐ray diffraction analysis, nuclear magnetic resonance spectroscopy, and thermogravimetric analysis. Owing to the nucleation at a high degree of supersaturation, thermodynamically unstable submicron non‐β‐form HMX particles were formed initially. Their morphology was changed to β‐form; the submicron size was maintained while the particles were entrapped in Estane. Estane was removed by washing with tetrahydrofuran, and the purity of the submicron β‐form HMX particles was greater than 99 %.
Effects of standardized health education pathway on patients undergoing endobronchial ultrasound‐guided transbronchial needle aspiration
Authors: Mao Changmin , Cheng Jing , Xia Hongxiang , Li Jing , Zhou Jing , Meng Aifeng , Zhi Xiaoxu , Wang Meixiang
Published: March 2021

Background

To explore the application and effect of standardized health education pathway in patients undergoing EBUS‐TNBA.

Methods

Hundred and one patients undergoing EBUS‐TBNA for the first time from September 2017 to June 2018 were divided into the study group and the control group. Patients in the control group (n = 50)received routine health education, while those in the study group (n = 51) received health education intervention based on the standardized health education pathway. Differences of anxiety, heart rate and oxygen saturation recovery time, success rate of first intubation attempt, and patient satisfaction between the two groups were observed.

Results

Basic information of patients in the two groups was comparable (P > .05). The SAS scores of the recovery time of heart rate and oxygen saturation in the study group were observably lower than those in the control group (P < .05), while the success rate of first intubation attempt and the satisfaction rate of the patients in the study group were remarkably higher (P < .05).

Conclusion

Health education based on the standardized pathway can reduce the anxiety level of patients undergoing EBUS‐TNBA, reduce the operation time, and improve the success rate of first intubation attempt as well as the satisfaction of patients.
Transcript analysis of commercial prostate cancer risk stratification panels in hard‐to‐predict grade group 2–4 prostate cancers
Authors: Lehto Timo‐Pekka K. , Stürenberg Carolin , Malén Adrian , Erickson Andrew M. , Koistinen Hannu , Mills Ian G. , Rannikko Antti , Mirtti Tuomas
Published: March 2021

Background

Improved prognostication is needed to minimize overtreatment in grade group (GG) 2–4 prostate cancer. Our aim was to determine, at messenger RNA (mRNA) level, the performance of the genes in the commercial panels Decipher, Oncotype DX, Prolaris, and mutational panel MSK‐IMPACT to predict metastasis‐free and prostate cancer‐specific death (PCSD) in patients with GG 2–4 prostate cancer at radical prostatectomy.

Methods

The retrospective cohort consisted of GG 2–4 patients treated with radical prostatectomy (median follow‐up 10.4 years). Seventy‐six cases with postoperative metastasis or PCSD and 84 controls with similar clinical baseline risk, but without progression, were analyzed. Index lesion mRNA transcripts were analyzed using NanoString technology. Random forest models were trained using panel gene sets to predict clinical endpoints and area under the curve (AUC), sensitivity, specificity, Youden index, and number needed to diagnose (NND) was measured. Survival probability was assessed with Kaplan–Meier estimator.

Results

All gene sets outperformed clinical parameters and predicted metastasis‐free and prostate cancer‐specific survival. However, there were significant differences between the panels. In metastasis prediction, the genes in Oncotype DX had inferior performance (area under the curve [AUC] = 0.65) compared to other panels (AUC = 0.73–0.74). Decipher, MSK‐IMPACT and Prolaris showed similar NND (2.83–3.12) with Oncotype DX having highest NND (4.79). In PCSD prediction, the Prolaris gene set performed worse (AUC = 0.66) than MSK‐IMPACT or Decipher (AUC = 0.72). Oncotype DX performed similarly to other panels (AUC = 0.69, p > .05). Oncotype DX demonstrated lowest NND (2.79) compared to other panels (4.22–5.66).

Conclusion

Transcript analysis of genes included in commercial panels is feasible in survival prediction of GG 2‐4 patients after radical prostatectomy and may aid in clinical decision making. There were significant differences between the panels, and overall stronger predictive gene sets are needed. Prospective investigation is warranted in biopsy materials.
Bandgap Tailoring of Monoclinic Single‐Phase β‐(AlxGa1−x)2O3 (0 ≤ x ≤ 0.65) Thin Film by Annealing β‐Ga2O3/Al2O3 Heterojunction at High Temperatures
Authors: Li Zhengcheng , Wu Ying , Feng Boyuan , Li Yao , Liu Tong , Feng Jiagui , Chen Xiao , Huang Rong , Xu Leilei , Li Zhiyun , Hu Nan , Li Fangsen , Jia Zhitai , Niu Gang , Guo Qixin , He Gaohang , Ding Sunan
Published: March 2021

Herein, bandgap tuning of monoclinic (−201)‐oriented β‐(AlxGa1−x)2O3 thin films is achieved through a β‐Ga2O3/Al2O3 heterojunction by a feasible annealing process with an O2 atmosphere. During the annealing process, Al atoms of the Al2O3 substrate outdiffuse easily into the β‐Ga2O3 thin film deposited by ozone‐assisted molecular beam epitaxy (OMBE). The Al compositions in the β‐(AlxGa1−x)2O3 samples are tuned through adjusting the annealing temperature from 800 to 1300 °C and experimentally determined from the result of X‐ray photoelectron spectroscopy (XPS) measurements combined with Vegard's law. Successive Al‐composition‐gradient β‐(AlxGa1−x)2O3 thin films with controlled bandgap are constructed. On these bases, β‐Ga2O3 thin films are deposited on β‐(AlxGa1−x)2O3 (0 ≤ x ≤ 0.65) substrates through OMBE, yielding β‐Ga2O3/β‐(AlxGa1−x)2O3 (0 ≤ x ≤ 0.65) heterojunction structures, and the band offsets of this heterojunction are determined by XPS accordingly. This methodology to achieve high‐quality β‐(AlxGa1−x)2O3 thin films with adjustable Al composition and tunable band offsets of the β‐Ga2O3/β‐(AlxGa1−x)2O3 interface will provide guidance for potential strategies to develop and fabricate β‐(AlxGa1−x)2O3‐based deep‐UV photodetectors and power devices.
Using recurrent time‐to‐event models with multinomial outcomes to generate toxicity profiles
Authors: Gebski Val , Marschner Ian , Asher Rebecca , Byth Karen
Published: March 2021

Most clinical studies, which investigate the impact of therapy simultaneously, record the frequency of adverse events in order to monitor safety of the intervention. Study reports typically summarise adverse event data by tabulating the frequencies of the worst grade experienced but provide no details of the temporal profiles of specific types of adverse events. Such 'toxicity profiles' are potentially important tools in disease management and in the assessment of newer therapies including targeted treatments and immunotherapy where different types of toxicity may be more common at various times during long‐term drug exposure. Toxicity profiles of commonly experienced adverse events occurring due to exposure to long‐term treatment could assist in evaluating the costs of the health care benefits of therapy. We show how to generate toxicity profiles using an adaptation of the ordinal time‐to‐event model comprising of a two‐step process, involving estimation of the multinomial response probabilities using multinomial logistic regression and combining these with recurrent time to event hazard estimates to produce cumulative event probabilities for each of the multinomial adverse event response categories. Such a model permits the simultaneous assessment of the risk of events over time and provides cumulative risk probabilities for each type of adverse event response. The method can be applied more generally by using different models to estimate outcome/response probabilities. The method is illustrated by developing toxicity profiles for three distinct types of adverse events associated with two treatment regimens for patients with advanced breast cancer.
Reliability analysis incorporating exponentiated inverse Weibull distribution and inverse power law
Authors: Sindhu Tabassum Naz , Atangana Abdon
Published: March 2021

In reliability research, electronic devices are an important part of our lives and modelling their lives is the most difficult and fascinating area. To investigate the failure functioning of electronic equipments, reliability monitoring of systems is widely used. However, it is stated in the literature that one in five electronic system collapses are a consequence of degradation and saving energy and forecasting future losses, it is necessary to summarize the data through certain versatile models of probability . In current article, a model of reliability formed on inverse power law and generalized inverse Weibull model is suggested. This current distribution presents a clearer framework to modelling the efficiency and functionality lifespan of electronic equipments. In this article, an empirical analysis is discussed related to life cycle of a surface‐mounted electrolytic capacitor (SMEC). In addition, it has noticed that evaluation of suggested distribution varies from classical model of inverse Weibull and that influences average time to failure (ATTF) of the studied capacitor.
GC/MSn analysis of the crude reaction mixtures from Friedel–Crafts acylation: Unambiguous identification and differentiation of 3‐aroylbenzofurans from their 4‐ and 6‐regioisomers
Authors: Begala Michela , Mancinelli Michele , Quezada Elias , Delogu Giovanna Lucia
Published: March 2021

Rationale

3‐Aroylbenzofurans and their 2‐nitrophenyl derivatives constitute fundamental intermediates for the synthesis of target compounds with pharmaceutical properties. However, their preparation via the Friedel–Crafts acylation of 2‐phenylbenzofurans, using Lewis acid as catalyst, often leads to mixtures of regioisomeric aroylbenzofurans that can be challenging to distinguish, thus preventing the reaction characterization.

Method

We report a method for the unambiguous identification and differentiation of the desired 3‐benzoyl isomers from their 4‐ and 6‐regioisomers in a crude reaction mixture using gas chromatography coupled to multiple‐stage mass spectrometric (GC/MSn) analysis performed in collision‐induced dissociation (CID) mode.

Results

Upon electron ionization, each set of isomers displayed nearly identical mass spectra. MSn revealed fragmentation patterns that varied in the location of the benzoyl group on the benzofuran scaffold: CID experiments performed on the molecular ion allowed the distinction of the 3‐acyl isomers from the 4‐ and 6‐regioisomers; CID experiments on the [M − Ar]+ ion allowed the distinction of the 4‐benzoyl from the 6‐benzoyl regioisomer, when the nitro group is located on the 2‐phenyl ring. Moreover, the unusual loss of OH• radical allowed ascertaining the position of the nitro group in 3‐acyl regioisomers bearing the NO2 group. The origin of the diagnostic OH• loss was investigated through MSn experiments using 18O‐labelled 3‐benzoyl derivatives.

Conclusions

The method allows the rapid characterization of crude reaction mixtures of benzoylbenzofurans using solely GC/MSn analysis, simplifying the workflow of extensive isolation and purification for structure elucidation.
Chromosomal analyses of human giant diploid oocytes by next‐generation sequencing
Authors: Kawano Hiroomi , Yamashita Naoki , Ito Junya , Kashiwazaki Naomi
Published: March 2021

Purpose

Although giant oocytes (GOs) having about twice cytoplasmic volume compared with general oocytes in mammals including the human are rarely recovered, it is thought that GOs have potentially chromosomal abnormalities. The aim of the present study was to assess chromosome numbers in chromosome‐spindle complexes (CSCs) and polar bodies of human GOs by using micromanipulation for sampling and next‐generation sequencing (NGS) for analyses of the chromosome numbers.

Methods

When recovered oocytes whose cytoplasm has lager than 140 µm or above, the oocytes were defined as GOs, and recovered GOs were vitrified. After warming, the CSCs, polar bodies, and enucleated cytoplasm were collected by micromanipulation from 3 GOs. The collected samples were analyzed by NGS.

Results

Chromosomal aneuploidy in the GOs was confirmed in all the three GOs. Comparing the CSCs with the chromosomes from polar bodies, the deletion and overlapping chromosome numbers were complementary in each GO.

Conclusions

The authors could collect the CSCs and the polar bodies from human GOs by micromanipulation, and then could analyze the chromosome numbers of the GOs by NGS method. As our data suggest that human GOs have chromosomal abnormalities, GOs should be excluded from clinical purpose as gamete sources for embryo transfer in the human.
Adaptive tracking control of stochastic switched nonlinear systems with unknown dead‐zone output
Authors: Liu Yanli , Ma Hongjun
Published: March 2021

In this article, the problem of adaptive output feedback control is carried out for stochastic switched nonlinear systems with dead‐zone output and asymmetric tracking constraints. A type of smooth approximate model is proposed, which unfastens the nondifferentiable phenomena of dead‐zone output. The Nussbaum‐type function is utilized to develop the control design of the unknown dead‐zone output. Subsequently, an improved first‐order filter is cooperated into the barrier Lyapunov function analysis, which avoids the repeated derivative problem of virtual control inputs in the backstepping design procedure and completes the control design successfully. The proposed constructive control algorithm can achieve the control goal well. Finally, a numerical example with comparison results is given to further verify the validity of the new control tactic.
Sample size re‐estimation for covariate‐adaptive randomized clinical trials
Authors: Li Xin , Ma Wei , Hu Feifang
Published: March 2021

Covariate‐adaptive randomization (CAR) procedures have been developed in clinical trials to mitigate the imbalance of treatments among covariates. In recent years, an increasing number of trials have started to use CAR for the advantages in statistical efficiency and enhancing credibility. At the same time, sample size re‐estimation (SSR) has become a common technique in industry to reduce time and cost while maintaining a good probability of success. Despite the widespread popularity of combining CAR designs with SSR, few researchers have investigated this combination theoretically. More importantly, the existing statistical inference must be adjusted to protect the desired type I error rate when a model that omits some covariates is used. In this article, we give a framework for the application of SSR in CAR trials and study the underlying theoretical properties. We give the adjusted test statistic and derive the sample size calculation formula under the CAR setting. We can tackle the difficulties caused by the adaptive features in CAR and prove the asymptotic independence between stages. Numerical studies are conducted under multiple parameter settings and scenarios that are commonly encountered in practice. The results show that all advantages of CAR and SSR can be preserved and further improved in terms of power and sample size.
Potential of Magnetic Hyperthermia to Stimulate Localized Immune Activation
Authors: Carter Thomas J. , Agliardi Giulia , Lin Fang‐Yu , Ellis Matthew , Jones Clare , Robson Mathew , Richard‐Londt Angela , Southern Paul , Lythgoe Mark , Zaw Thin May , Ryzhov Vyacheslav , de Rosales Rafael T. M. , Gruettner Cordula , Abdollah Maha R. A. , Pedley R. Barbara , Pankhurst Quentin A. , Kalber Tammy L. , Brandner Sebastian , Quezada Sergio , Mulholland Paul , Shevtsov Maxim , Chester Kerry
Published: March 2021

Magnetic hyperthermia (MH) harnesses the heat‐releasing properties of superparamagnetic iron oxide nanoparticles (SPIONs) and has potential to stimulate immune activation in the tumor microenvironment whilst sparing surrounding normal tissues. To assess feasibility of localized MH in vivo, SPIONs are injected intratumorally and their fate tracked by Zirconium‐89‐positron emission tomography, histological analysis, and electron microscopy. Experiments show that an average of 49% (21–87%, n = 9) of SPIONs are retained within the tumor or immediately surrounding tissue. In situ heating is subsequently generated by exposure to an externally applied alternating magnetic field and monitored by thermal imaging. Tissue response to hyperthermia, measured by immunohistochemical image analysis, reveals specific and localized heat‐shock protein expression following treatment. Tumor growth inhibition is also observed. To evaluate the potential effects of MH on the immune landscape, flow cytometry is used to characterize immune cells from excised tumors and draining lymph nodes. Results show an influx of activated cytotoxic T cells, alongside an increase in proliferating regulatory T cells, following treatment. Complementary changes are found in draining lymph nodes. In conclusion, results indicate that biologically reactive MH is achievable in vivo and can generate localized changes consistent with an anti‐tumor immune response.
Intralayered Ostwald Ripening‐Induced Self‐Catalyzed Growth of CNTs on MXene for Robust Lithium–Sulfur Batteries
Authors: Xu Mengyao , Liang Lin , Qi Jing , Wu Tianli , Zhou Dan , Xiao Zhubing
Published: March 2021

The distinguishable physicochemical properties of MXenes render them attractive in electrochemical energy storage. However, the strong tendency to self‐restack owing to the van der Waals interactions between the MXene layers incurs a massive decrease in surface area and blocking of ions transfer and electrolytes penetration. Here, in situ generated Ti3C2Tx MXene‐carbon nanotubes (Ti3C2Tx‐CNTs) hybrids are reported via low‐temperature self‐catalyzing growth of CNTs on Ti3C2Tx nanosheets without the addition of any catalyst precursors. With combined spectroscopic studies and theoretical calculation results, it is certified that the intralayered Ostwald ripening‐induced Ti3C2Tx nanomesh structure contributes to the uniform precipitation of ultrafine metal Ti catalysts on Ti3C2Tx, thus giving rise to the in situ CNTs formation on the surface of Ti3C2Tx with high integrity. Taking advantages of intimate electrolyte penetration, unobstructed 3D Li+/e transport, and rich electroactive sites, the Ti3C2Tx‐CNTs hybrids are confirmed to be ideal 3D scaffolds for accommodating sulfur and regulating the polysulfides conversion for high‐loaded lithium–sulfur batteries.
Multi‐Phase Heterostructure of CoNiP/CoxP for Enhanced Hydrogen Evolution Under Alkaline and Seawater Conditions by Promoting H2O Dissociation
Authors: Liu Dong , Ai Haoqiang , Chen Mingpeng , Zhou Pengfei , Li Bowen , Liu Di , Du Xinyu , Lo Kin Ho , Ng Kar‐Wei , Wang Shuang‐Peng , Chen Shi , Xing Guichuan , Hu Jinsong , Pan Hui
Published: March 2021

Hydrogen evolution reaction (HER) is a key step for electrochemical energy conversion and storage. Developing well defined nanostructures as noble‐metal‐free electrocatalysts for HER is promising for the application of hydrogen technology. Herein, it is reported that 3D porous hierarchical CoNiP/CoxP multi‐phase heterostructure on Ni foam via an electrodeposition method followed by phosphorization exhibits ultra‐highly catalytic activity for HER. The optimized CoNiP/CoxP multi‐phase heterostructure achieves an excellent HER performance with an ultralow overpotential of 36 mV at 10 mA cm−2, superior to commercial Pt/C. Importantly, the multi‐phase heterostructure shows exceptional stability as confirmed by the long‐term potential cycles (30,000 cycles) and extended electrocatalysis (up to 500 h) in alkaline solution and natural seawater. Experimental characterizations and DFT calculations demonstrate that the strong electronic interaction at the heterointerface of CoNiP/CoP is achieved via the electron transfer from CoNiP to the heterointerface, which directly promotes the dissociation of water at heterointerface and desorption of hydrogen on CoNiP. These findings may provide deep understanding on the HER mechanism of heterostructure electrocatalysts and guidance on the design of earth‐abundant, cost‐effective electrocatalysts with superior HER activity for practical applications.
Bottom‐Up Synthesis of Hexagonal Boron Nitride Nanoparticles with Intensity‐Stabilized Quantum Emitters
Authors: Chen Yongliang , Xu Xiaoxue , Li Chi , Bendavid Avi , Westerhausen Mika T. , Bradac Carlo , Toth Milos , Aharonovich Igor , Tran Toan Trong
Published: March 2021

Fluorescent nanoparticles are widely utilized in a large range of nanoscale imaging and sensing applications. While ultra‐small nanoparticles (size ≤10 nm) are highly desirable, at this size range, their photostability can be compromised due to effects such as intensity fluctuation and spectral diffusion caused by interaction with surface states. In this article, a facile, bottom‐up technique for the fabrication of sub‐10‐nm hexagonal boron nitride (hBN) nanoparticles hosting photostable bright emitters via a catalyst‐free hydrothermal reaction between boric acid and melamine is demonstrated. A simple stabilization protocol that significantly reduces intensity fluctuation by ≈85% and narrows the emission linewidth by ≈14% by employing a common sol–gel silica coating process is also implemented. This study advances a promising strategy for the scalable, bottom‐up synthesis of high‐quality quantum emitters in hBN nanoparticles.
Effect of age and waste crumb rubber aggregate proportions on flexural characteristics of self‐compacting rubberized concrete
Authors: Wanasinghe Dimuthu , Aslani Farhad , Dai Kunyou
Published: March 2021

Generation of waste has been a significant problem in recent decades in many engineering fields. Self‐compacting rubberized concrete (SCRC) is a new type of SCC, which replaces part of natural aggregates by rubber aggregates in SCC to increase the application range of waste tyre rubber. This study investigates the effect of age and crumb rubber aggregate ratio on fresh and mechanical performance. Eight different SCRC mixtures using 2–5 mm rubber aggregates to replace 10%, 20%, 30%, and 40% natural aggregates by volume respectively, and 5–10 mm rubber aggregates to replace 10%, 20%, 30%, and 40% natural aggregates by volume respectively, are tested after 7, 28, 56, and 91 days for their mechanical properties. Results show that both the compressive and the tensile strength increase with the aging time, both of these properties drop with the amount and size of the crumb rubber content. Similar to compressive and tensile properties, flexural toughness and the modulus of rupture showed increased with the aging time. Small addition of crumb rubber has shown improvements in both rupture and fracture toughness properties, which diminishes when the crumb rubber content becomes significantly large.
Performance of self‐compacting rubberized concrete against carbonation and chloride penetration
Authors: Mallek Jihen , Daoud Atef , Omikrine‐Metalssi Othman , Loulizi Amara
Published: March 2021

This study assessed the performance of self‐compacting rubberized concrete against carbonation and chloride penetration. In addition to fresh‐state and compressive strength tests, durability of the studied mixes was evaluated by measuring carbonation and chloride penetration depths, total porosity, and pores'size distribution. It was found that an increase in rubber content leads to a decrease in compressive strength. However, stadequate strength for structural applications was achieved up to an incorporation of 15% rubber by volume. As for durability, the presence of rubber was found to enhance performance against carbonation, but to worsen the resistance to chloride ion penetration.
How Glycine Betaine Modifies Lipid Membrane Interactions
Authors: Shakhman Yuri , Harries Daniel
Published: March 2021

Ubiquitous in the cellular milieu, small organic compounds termed osmolytes help to regulate the response to environmental stress. Elasmobranchii, such as sharks, accumulate high concentrations of several osmolytes, most notably urea, trimethylamine N‐oxide (TMAO), and glycine betaine (GB). These three compounds are used to osmoregulate the organism's body fluids, so that they counteract seawater salinity, as well as the destabilizing effects of hydrostatic pressure on cells and their molecular components. Herein we focus on glycine betaine and show how it modifies interactions between lipid membranes. We find that the addition of GB exerts an apparent attractive force that draws neighboring membranes toward one another. We show that, at the molecular level, this apparent attraction between membranes in the presence of GB is due to its preferential exclusion from the space between adjacent membranes, which thereby exerts an osmotic pressure that brings membranes closer together. This action is similar to the one we have previously reported for TMAO. However, we find that the net effect of GB is significantly smaller than that of TMAO, because GB concomitantly significantly weakens van der Waals attractions between membranes by changing the dielectric properties of the intervening solution. Finally, we show how GB acts in combination with urea. At high total concentrations and over a wide range of GB‐to‐urea ratios, urea counteracts the effect of GB, so that the equilibrium separation between membranes is close to their values in pure water. This finding supports the prevailing idea that mixtures of several osmolytes can achieve minimal net impact on biomacromolecular stability while also counteracting osmotic stress.
Transition‐Metal‐Free C−S, C−Se, and C−Te Bond Formation from Organoboron Compounds
Authors: Sacramento Manoela , Costa Gabriel P. , Barcellos Angelita M. , Perin Gelson , Lenardão Eder J. , Alves Diego
Published: March 2021

The present review describes the successful application of organoboron compounds in transition‐metal‐free C−S, C−Se, and C−Te bond formations. We presented studies regarding these C‐Chalcogen bond formations using organoboron reagents, such as boronic acids, boronic esters, borate anions, and several sources of chalcogen atoms/moieties. Moreover, a broad range of transition‐metal‐free approaches to synthesize sulfides, selenides, and tellurides were described using conventional heating methods, which are sometimes green since they use green solvents, safe reagents, among others. Furthermore, protocols using alternative energy sources, including ultrasound, microwave irradiation, photocatalysis, and electrolytic processes, were also shown to be suitable. These protocols were applied to prepare a broad scope of functionalized chalcogenides with high molecular diversity. These studies and their proposed mechanisms were also reported herein in addition to the reuse of reaction promoters.
A Parisian Vision of the Chemistry of Hypercoordinated Silicon Derivatives
Authors: Lemière Gilles , Millanvois Alexandre , Ollivier Cyril , Fensterbank Louis
Published: March 2021

Less than ten years of acquaintance with hypercoordinated silicon derivatives in our lab is described in this account. Martin's spirosilane derivatives open new opportunities as ligands and as agents for the activation of small molecules and bis‐catecholato silicates have proven to be exquisite radical precursors in photoredox conditions for broad synthetic applications.
Observations on spindly leg syndrome in a captive population ofAndinobates geminisae
Authors: Higgins Kathleen , Guerrel Jorge , Lassiter Elliot , Mooers Arne , Palen Wendy J. , Ibáñez Roberto
Published: March 2021

Amphibian health problems of unknown cause limit the success of the growing number of captive breeding programs. Spindly leg syndrome (SLS) is one such disease, where affected individuals with underdeveloped limbs often require euthanization. We experimentally evaluated husbandry‐related factors of SLS in a captive population of the critically endangered frog,Andinobates geminisae. SLS has been linked to tadpole nutrition, vitamin B deficiency, water filtration methods, and water quality, but few of these have been experimentally tested. We tested the effects of water filtration method and vitamin supplementation (2017) and the effects of tadpole husbandry protocol intensity (2018) on time to metamorphosis and the occurrence of SLS. We found that vitamin supplementation and reconstituted reverse osmosis filtration of tadpole rearing water significantly reduced SLS prevalence and that reduced tadpole husbandry delayed time to metamorphosis. A fortuitous accident in 2018 resulted in a decrease in the phosphate content of rearing water, which afforded us an additional opportunity to assess the influence of phosphate on calcium sequestration. We found that tadpoles that had more time to sequester calcium for ossification during development had decreased the prevalence of SLS. Taken together, our results suggest that the qualities of the water used to rear tadpoles plays an important role in the development of SLS. Specifically, filtration method, vitamin supplementation, and calcium availability of tadpole rearing water may play important roles. Focused experiments are still needed, but our findings provide important information for amphibian captive rearing programs affected by high SLS prevalence.
Higher spins from exotic dualisations
Authors: Boulanger Nicolas , Lekeu Victor
Published: March 2021

Abstract

At the free level, a given massless field can be described by an infinite number of different potentials related to each other by dualities. In terms of Young tableaux, dualities replace any number of columns of height hi by columns of height D − 2 − hi, where D is the spacetime dimension: in particular, applying this operation to empty columns gives rise to potentials containing an arbitrary number of groups of D − 2 extra antisymmetric indices. Using the method of parent actions, action principles including these potentials, but also extra fields, can be derived from the usual ones. In this paper, we revisit this off-shell duality and clarify the counting of degrees of freedom and the role of the extra fields. Among others, we consider the examples of the double dual graviton in D = 5 and two cases, one topological and one dynamical, of exotic dualities leading to spin three fields in D = 3.
Gravitational vector Dark Matter
Authors: Gross Christian , Karamitsos Sotirios , Landini Giacomo , Strumia Alessandro
Published: March 2021

Abstract

A new dark sector consisting of a pure non-abelian gauge theory has no renormalizable interaction with SM particles, and can thereby realise gravitational Dark Matter (DM). Gauge interactions confine at a scale ΛDM giving bound states with typical lifetimes $$ \tau \sim {M}_{\mathrm{P}1}^4/{\Lambda}_{\mathrm{DM}}^5 $$
τ
∼

M

P
1

4

/

Λ
DM
5

that can be DM candidates if ΛDM is below 100 TeV. Furthermore, accidental symmetries of group-theoretical nature produce special gravitationally stable bound states. In the presence of generic Planck-suppressed operators such states become long-lived: SU(N) gauge theories contain bound states with $$ \tau \sim {M}_{\mathrm{P}1}^8/{\Lambda}_{\mathrm{DM}}^9 $$
τ
∼

M

P
1

8

/

Λ
DM
9

; even longer lifetimes τ = (MPl/ΛDM)2N−4/ΛDM arise from SO(N) theories with N ≥ 8, and possibly from F4 or E8. We compute their relic abundance generated by gravitational freeze-in and by inflationary fluctuations, finding that they can be viable DM candidates for ΛDM ≳ 1010 GeV.
Continuous LTI Input–Output Stable Systems on $${L^{p}(\mathbb {R})}$$ and $${\mathscr {D'}_{L^{p}}(\mathbb {R})}$$ Associated with Differential Equations: Existence, Invertibility Conditions and Inversion
Authors: Ciampa M.
Published: March 2021

A usual problem in analog signal processing is to ascertain the existence of a continuous single-input single-output linear time-invariant input–output stable system associated with a linear differential equation, i.e., of a continuous system such that, for every input signal in a given space of signals, yields an output, in the same space, which verifies the equation with known term the input, and to ascertain the existence of its inverse system. In this paper, we consider, as space of signals, the usual Banach space of $${L^{p}}$$

L
p

functions, or the space of distributions spanned by $${L^{p}}$$

L
p

functions and by their distributional derivatives, of any order (input spaces which include signals with not necessarily left-bounded support), we give a systematic theoretical analysis of the existence, uniqueness and invertibility of continuous linear time-invariant input–output stable systems (both causal and non-causal ones) associated with the differential equation and, in case of invertibility, we characterize the continuous inverse system. We also give necessary and sufficient conditions for causality. As an application, we consider the problem of finding a suitable almost inverse of a causal continuous linear time-invariant input–output stable non-invertible system, defined on the space of finite-energy functions, associated with a simple differential equation.
Pathogen inferred to have dispersed thousands of kilometres at sea, infecting multiple keystone kelp species
Authors: Mabey Abigail L. , Parvizi Elahe , Fraser Ceridwen I.
Published: March 2021

Protistan pathogens have been found to infect populations of some large brown macroalgae. Infection could reduce the ability of macroalgae to withstand hydrodynamic pressures through weakening tissues and reducing flexibility. Widespread mortality of macroalgae if disease outbreaks were to occur could have important flow-on consequences for biodiversity and ecosystem function. Recent discoveries of the protistan pathogen Maullinia infecting the ecologically keystone southern bull kelp Durvillaea in Chile, Australia, and on Marion Island, raise the possibility that this pathogen is dispersing across ocean basins with buoyant hosts. To determine whether Maullinia also infects southern bull kelp in New Zealand, samples of gall-like tissue from Durvillaea antarctica, D. poha, and D. willana were collected from intertidal sites, and genetic analyses (sequencing of partial 18S rRNA) carried out. Maullinia infections were detected in all three species of Durvillaea. Phylogenetic analyses show a close relationship of New Zealand Maullinia to M. braseltonii previously detected in Chile and on Marion Island. Based on its genetic similarity to distant lineages and its presence on buoyant hosts that have been shown to drift long distances at seas, we infer that Maullinia has dispersed across the Southern Ocean through rafting of infected bull kelp. Understanding the capacity of pathogens to disperse across oceans is critical part of forecasting and managing ecosystem responses to environmental change.
Quantitative assessment of HCC wash-out on CT is a predictor of early complete response to TACE
Authors: Fronda Marco , Doriguzzi Breatta Andrea , Gatti Marco , Calandri Marco , Maglia Claudio , Bergamasco Laura , Righi Dorico , Faletti Riccardo , Fonio Paolo
Published: March 2021

Objectives

To investigate the predictive value of four-phase contrast-enhanced CT (CECT) for early complete response (CR) to drug-eluting-bead transarterial chemoembolization (DEB-TACE), with a particular focus on the quantitatively assessed wash-in and wash-out.

Methods

A retrospective analysis of preprocedural CECTs was performed for 129 HCC nodules consecutively subjected to DEB-TACE as first-line therapy. Lesion size, location, and margins were recorded. For the quantitative analysis, the following parameters were computed: contrast enhancement ratio (CER) and lesion-to-liver contrast ratio (LLC) as estimates of wash-in; absolute and relative wash-out (WOabs and WOrel) and delayed percentage attenuation ratio (DPAR) as estimates of wash-out. The early radiological response of each lesion was assessed by the mRECIST criteria and dichotomized in CR versus others (partial response, stable disease, and progressive disease).

Results

All quantitatively assessed wash-out variables had significantly higher rates for CR lesions (WOabsp = 0.01, WOrelp = 0.01, and DPAR p = 0.00002). However, only DPAR demonstrated an acceptable discriminating ability, quantified by AUC = 0.80 (95% CI0.73–0.88). In particular, nodules with DPAR ≥ 120 showed an odds ratio of 3.3(1.5–7.2) for CR (p = 0.0026). When accompanied by smooth lesion margins, DPAR ≥ 120 lesions showed a 78% CR rate at first follow-up imaging. No significative association with CR was found for quantitative wash-in estimates (CER and LLC).

Conclusions

Based on preprocedural CECT, the quantitative assessment of HCC wash-out is useful in predicting early CR after DEB-TACE. Among the different formulas for wash-out quantification, DPAR has the best discriminating ability. When associated, DPAR ≥ 120 and smooth lesion margins are related to relatively high CR rates.

Key Points

• A high wash-out rate, quantitatively assessed during preprocedural four-phase contrast-enhanced CT (CECT), is a favorable predictor for early radiological complete response of HCC to drug-eluting-bead chemoembolization (DEB-TACE).

• The arterial phase of CECT shows great dispersion of attenuation values among different lesions, even when a standardized protocol is used, limiting its usefulness for quantitative analyses.

• Among the different formulas used to quantify the wash-out rate (absolute wash-out, relative wash-out, and delayed percentage attenuation ratio), the latter (DPAR), based only on the delayed phase, is the most predictive (AUC = 0.80), showing a significant association with complete response for values above 120.
Vergleichende Analyse der Refraktions- und Topographieveränderungen nach lidchirurgischen Eingriffen
Authors: Mehlan J. , Jonca B. , Dulz S. , Green S. , Spitzer M. S. , Schüttauf F.
Published: March 2021

Hintergrund und Ziel der Arbeit

Über die Frage, ob nach Blepharoplastik, Levatorresektion oder lateraler Zügelplastik Refraktions- oder Topographieveränderungen zu erwarten sind, besteht weitestgehend Unklarheit.

Material und Methoden

Daher wurden in der vorliegenden Studie prä- sowie postoperativ von 78 Patienten objektive Refraktion, Vorderabschnittstomographie mittels Pentacam und Visusprüfung durchgeführt und der Analyse zugeführt. Die Untersuchung erfolgte präoperativ, zum Zeitpunkt des Fadenzugs nach 10 Tagen sowie nach 3 Monaten.

Ergebnisse

Wir fanden postoperativ weder nach Blepharoplastik noch nach lateraler Zügelplastik signifikante Veränderungen von Visus oder Refraktion noch in der Topographie. Hingegen zeigt der Wilcoxon-Vorzeichen Test 10 Tage nach der Levatorresektion einen signifikanten Anstieg des Zylinders nach 10 Tagen im Vergleich zum präoperativen Niveau (p = 0,042). Diese Veränderung war jedoch nach 3 Monaten nicht mehr nachweisbar.

Schlussfolgerung

Wir postulieren daher, dass eine umfangreiche Aufklärung von Patienten hinsichtlich passagerer Sehveränderungen insbesondere bei Levatorresektionen unabdingbar ist und postoperativ eine ergänzende Refraktions- und Topographiekontrolle sinnvoll sein kann.