bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of efficient, reusable, biomorphic hierarchical MgAlLa mixed metal oxides for removal of fluoride ions
Authors: Shi Yuemei , Li Qiurong , Xu Hua , Xiao Haiyan , Pei Jiarong , Zhang Tingting , Zhang Tao
Published: November 2022

As an easily available layered double hydroxides (LDHs), hydrotalcites show significant effect in the adsorption of various ions in wastewater. It is worth noting that the calcined products (LDOs) of LDHs as adsorbents have the advantages of large specific surface area, low cost, renewable and non‐toxic to the environment. Herein, sustainable, efficient, biological, and hierarchical structure MgAlLa mixed metal oxides using catkins as a template (BC‐LDOs) are reported. A facile synthetic approach was presented for hierarchical MgAlLa layered double hydroxides via the simple coprecipitation method followed by a subsequent calcination at 550°C for 3 h. BC‐LDOs were characterized with IR, XRD, SEM, TEM, and BET and were studied for their adsorption performance of fluoride. The results showed that high‐specific surface area of BC‐LDOs is 118.02 m2/g, which is 10 times higher than that of MgAlLa mixed metal oxides without template (MgAlLa‐LDOs). BC‐LDOs had the best adsorption effect at pH 4–5 and the removal efficiency could reach more than 98%. In the experimental results involved in the study, the maximum adsorption capacity is 33.15 mg/g. In addition, the adsorption process of fluoride ions conformed to the pseudo‐second‐order model and the Freundlich model. Furthermore, the synthesized BC‐LDOs were recyclable and still exhibited good adsorption effect after 5 times of regeneration. The innovation of this study lies in the introduction of multi‐fiber catkins. There is no report on the introduction of catkins into LDHs in relevant studies. Hence, BC‐LDOs have a broad application prospect in the treatment and adsorption of fluoride‐containing wastewater.
Theoretical analysis and experimental research on R1234yf as alternative to R134a in a heat pump system
Authors: Wang Hongli , Zhang Shuaihua , Li Huasong , Guo Xiaoying
Published: November 2022

With the growing awareness of dual threats of global warming potential (GWP) and ozone depletion potential (ODP), the theoretical analysis and experimental testing of R1234yf refrigerant as alternative to R134a in a heat pump were analyzed. The results show that when the discharge pressure decreases from 1.6 MPa to 0.9 MPa, the heating COPh of R134a and R1234yf heat pumps decreases by 26.97% and 28.78%, respectively. When the evaporation temperature increases from −10 to 10°C, the heating COPh of R134a and R1234yf heat pumps increases by 12.68% and 20.88%. When the cooling water volume flow increases from 0.14m3/h to 0.35m3/h, the heating COPh of R134a and R1234yf heat pumps increases by 13.07% and 6.56%. When the chilled water volume flow increases from 0.35 to 0.53 m3/h, the heating COPh of R134a and R1234yf heat pumps increases by 30.31% and 29.38%. The error of theoretical calculation and experimental testing is between +10% and −15%.
Effect of oxides composition on the mechanical properties of non‐sintered spherical filters from waste steel slag
Authors: Yan Xiaoya , Shen Xinyu , Lin Yang , Xu Yueqing , Han Yan , Liu Rong
Published: November 2022

Non‐sintered spherical filters (NSSFs) from the waste steel slag for bottom filtration process are regarded as promising materials for sustainable development with economical benefits due to saving natural resource pebbles. To further optimize the preparation process, the influence mechanism of the main oxides on characteristics are comprehensively examined in this work. CaO in the raw materials makes it easier to release active components from the resulting glass body structure, while the expansion stress of Ca(OH)2 crystals precipitated under highly basic circumstances needs special consideration. SiO2 can positively contribute to the properties due to its adequate participation in the hydration reaction and the micro‐aggregate effect. Al3+ tends to combine and form a stable tetrahedral structure, which is conducive to liquid viscosity and the hindrance of hydration reaction of the active substance. Under the 6% mass ratio of MgO, NSSFs exhibit relatively excellent in physical properties. Specifically, the stimulation and promotion effect of MgO on hydration reaction is superior to the negative effect of excessive product Mg(OH)2 on expansion stress. Fe2O3 particles convert the structure in NSSFs to a dense state by the filling effect and serving as nucleation sites to promote the formation of hydration products.
Insights into the particle diameter and base chosen for dry powder fire extinguishing agents
Authors: Zhao Junchao , Xue Feng , Fu Yangyang , Lu Song , Zhang Heping
Published: November 2022

Sodium bicarbonate and potassium bicarbonate are commonly used as the bases of dry powder fire extinguishing agents. However, the choices of particle diameter and base are still not obvious, bringing difficulties to the design of fire extinguishing agents. Through the study on thermal decomposition kinetics, it was found that the smaller the particle size, the faster the decomposition rate of dry powder agents. For instance, if the D90 of sodium bicarbonate is reduced from 46.2 to 1 μm, the decomposition rate triples. As determined by thermal decomposition experiments, the residues after a fire could be bicarbonates, carbonates, and mixtures. The residue solutions' pH shows that carbonates are more alkaline than bicarbonates, and potassium salts are more alkaline than sodium salts. The corrosion tests on four common metals reveal that the residues of potassium bicarbonate after a fire could accelerate the electrochemical corrosion of metal surfaces, especially aluminum alloys. This research identifies the ideal particle diameter and supports the choice of alkali metal salts for the design of dry powder agents.
Diversity, equity, and inclusion in gastroenterology and hepatology: A survey of where we stand
Authors: Rahal Harman K. , Tabibian James H. , Issaka Rachel B. , Quezada Sandra , Gray Darrell M. , Balzora Sophie , Yang Liu , Badiee Jayraan , May Folasade P.
Published: November 2022

Background and Aims

In the setting of increasing attention to representation in medicine, we aimed to assess current perspectives of racial and ethnic workforce diversity and health care disparities among gastroenterology (GI) and hepatology professionals in the United States.

Approach and Results

We developed and administered a 33‐item electronic cross‐sectional survey to members of five national GI and hepatology societies. Survey items were organized into thematic modules and solicited perspectives on racial and ethnic workforce diversity, health care disparities in GI and hepatology, and potential interventions to enhance workforce diversity and improve health equity. Of the 1219 survey participants, 62.3% were male, 48.7% were non‐Hispanic White, and 19.9% were from backgrounds underrepresented in medicine. The most frequently reported barriers to increasing racial and ethnic diversity in GI and hepatology were insufficient representation of underrepresented racial and ethnic minority groups in the education and training pipeline (n = 431 [35.4%]), in professional leadership (n = 340 [27.9%]), and among practicing GI and hepatology professionals (n = 324 [26.6%]). Suggested interventions were to increase career mentorship opportunities (n = 545 [44.7%]), medical student opportunities (n = 520 [42.7%]), and program and professional society leadership roles for underrepresented racial and ethnic minority groups (n = 473 [38.8%]).

Conclusions

Our survey explored imperative and timely perspectives on racial and ethnic representation and health equity among professionals in GI and hepatology. The findings should inform future interventions to address workforce diversity and establish priorities toward improving health equity, ultimately serving as a springboard for professional societies, academic institutions, and other organizations that aim to increase diversity, equity, and inclusion in our field.
Cautionary tale of right ventricular perforation during Micra™ leadless pacemaker insertion
Authors: Gulkarov Iosif , Stein Louis H. , Karanam Ravindranath N. , Lackey Adam , Dobesh David , Ahmad Ahsanuddin , Salemi Arash
Published: November 2022

Transcatheter pacing systems are self‐contained, leadless, devices that offer the potential benefits of avoiding complications related to pectoral pocket and upper extremity vascular access. These systems in preapproval trials demonstrated excellent safety profile with the incidence of device‐related cardiac perforation as low as 1.6% with Micra™ (Medtronic) and 1.3% in Nanostim (Abbott). In post‐approval registry of Micra™ TPS, the rate of major complications was even lower than in the investigational study ranging from 0.63% to 0.77%. Recently, published report found much higher rates of need for rescue surgery, shock, tamponade, and death among patients implanted with the Micra™ device when compared with transvenous devices. This case report describes two cases of major right ventricular perforation requiring surgical intervention.
Interleukin‐2 promotes pegylated interferon alpha for hepatitis B surface antigen loss: A retrospective pragmatic clinical study at the Fourth Affiliated Hospital of Zhejiang University Medical College
Authors: Qi Wencai , Wang Yuming , Huang Guangyu , Wang Kaifa
Published: November 2022

Background and Aims

Interleukin‐2 (IL‐2) can be used as an adjuvant therapy when pegylated interferon alpha (Peg‐IFN‐α) does not effectively promote hepatitis B surface antigen (HBsAg) loss, but the relevant timing, kinetic patterns, and prognostic associations of this intervention are unclear.

Methods

A total of 115 patients with chronic hepatitis B (CHB) treated at our institution between October 2018 and March 2021 were included in this retrospective analysis. They were divided into two kinetic patterns by using K‐medoids cluster analysis. Profile and prognostic associations were statistically analyzed between the two patterns.

Results

After baseline standardization, before the intervention, the relative HBsAg level showed a continuously increasing trend, but after the intervention, it showed a continuously decreasing trend. Based on the relative change in the HBsAg level, two kinetic patterns, namely, a fluctuation platform pattern and a stepwise growth pattern, were identified by using K‐medoids cluster analysis for all 115 patients before IL‐2 intervention. Profile analysis showed that there were statistically significant differences between the two patterns before IL‐2 intervention (p < 0.05), but their profiles showed the same trend after 2 weeks of IL‐2 intervention. Prognostic association analysis showed that CD8+ T cells, alanine transaminase (ALT), age, natural killer (NK) cells, neutrophils, and course of treatment before IL‐2 intervention were the six main indicators affecting the relative decrease in the HBsAg level.

Conclusion

For CHB patients who have received continuous Peg‐IFN‐α treatment, IL‐2 intervention should be given as early as possible when the HBsAg level has not decreased for four consecutive weeks or a fluctuation platform pattern is observed. After the intervention, a downward relative change in the HBsAg level can be maintained over 4 weeks. CD8+ T cells, ALT, NK cells, and neutrophils are baseline indicators closely related to the prognosis of this intervention.
Surgical disorders in pediatric and adolescent gynecology: Adnexal abnormalities
Authors: Mentessidou Anastasia , Mirilas Petros
Published: November 2022

Surgical abnormalities of the adnexa in children and adolescents include a variety of ovarian and paraovarian lesions ranging from benign functional cysts to malignant tumors, torsion of the ovary and/or the fallopian tube, and adnexal infectious lesions ranging from salpingitis to tubo‐ovarian abscesses. Presentations vary from asymptomatic pelvic masses to acute abdomen, and some ovarian tumors might present with precocious puberty or virilization. Acute pain might be caused by hemorrhage or rupture of ovarian or paraovarian cysts, adnexal torsion or adnexal infection. Differential diagnosis of adnexal masses should include peri‐appendiceal abscess in all age groups, and endometriomas and ectopic pregnancy in adolescents. This review provides guidance on the differentiation between adnexal abnormalities, based on important clues from clinical assessment and diagnostic workup, and ultimately on the decision making about the need for surgery, its level of urgency, and the type of surgery to clinicians of all specialties involved in the care of young females.
A literature review and proposed framework for a core curriculum in obstetrics and gynecology for medical students globally
Authors: Atiomo William U. , Stanley Adrian G. , Ezimokhai Mutairu M.
Published: November 2022

Background

There have been challenges in deciding the curricular content in obstetrics and gynecology (Ob/Gyn) for medical students because the core knowledge, competencies, and duration of Ob/Gyn clerkships, varies widely by country.

Objectives

To investigate current recommendations for Ob/Gyn curricula for medical students globally, in a rapid review of the literature and websites of a selection of medical schools.

Search Strategy

A targeted search of selected databases (PubMed and Google Scholar) using relevant key words and a search of university websites.

Selection Criteria

Studies that applied to medical or undergraduate students in Ob/Gyn.

Data Collection and Analysis

A standardized extraction form on Microsoftexcelto extract and chart data.

Main Results

We identified recommendations from national professional bodies (Royal College of Obstetricians and Gynaecologists, Royal Australian and New Zealand College of Obstetricians and Gynaecologists, Association of Professors of Gynecology and Obstetrics, and the Turkish‐National Core Curriculum), and descriptions from five university websites. We also identified additional objectives, including teaching on intimate partner violence, health priorities in low‐ and middle‐income countries, and a variation in practical skills recommended.

Conclusions

Fitting all the recommended curricula content into medical student Ob/Gyn clerkships is a challenge. A framework to address this, for consideration by the International Federation of Gynaecology and Obstetrics and other stakeholders, is proposed in which priority is given to topics related to emergency Ob/Gyn, history taking, and examination of the pregnant and non‐pregnant patient.
Structural stability and the low‐lying singlet and triplet states of BN‐n‐acenes, n = 1–7
Authors: Milanez Bruno D. , dos Santos Gustavo M. , Pinheiro Max , Ueno Leonardo T. , Ferrão Luiz F. A. , Aquino Adelia J. A. , Lischka Hans , Machado Francisco B. C.
Published: November 2022

The chemical stability and the low‐lying singlet and triplet excited states of BN‐n‐acenes (n = 1–7) were studied using single reference and multireference methodologies. From the calculations, descriptors such as the singlet‐triplet splitting, the natural orbital (NO) occupations and aromaticity indexes are used to provide structural and energetic analysis. The boron and nitrogen atoms form an isoelectronic pair of two carbon atoms, which was used for the complete substitution of these units in the acene series. The structural analysis confirms the effects originated from the insertion of a uniform pattern of electronegativity difference within the molecular systems. The covalent bonds tend to be strongly polarized which does not happen in the case of a carbon‐only framework. This effect leads to a charge transfer between neighbor atoms resulting in a more strengthened structure, keeping the aromaticity roughly constant along the chain. The singlet‐triplet splitting also agrees with this stability trend, maintaining a consistent gap value for all molecules. The BN‐n‐acenes molecules possess a ground state with monoconfigurational character indicating their electronic stability. The low‐lying singlet excited states have charge transfer character, which proceeds from nitrogen to boron.
Model‐Informed Dose Justifications of Posaconazole in Japanese Patients for Prophylaxis and Treatment Against Fungal Infection
Authors: Iwasa Takashi , de Almeida Camila , Fauchet Floris , Winchell Gregory A. , de Greef Rik , Hasegawa Chihiro , Yoshitsugu Hiroyuki , Wrishko Rebecca Ellen
Published: November 2022

Posaconazole is a globally approved broad‐spectrum triazole antifungal compound. In Japanese patients, posaconazole has identical dosing regimens as those approved globally for both tablet and intravenous formulations. This article aims to describe a model‐informed approach for dose justification of posaconazole in the Japanese population as either high‐risk patients with fungal infections (prophylaxis patients) or patients with fungal infections (treatment patients). A simultaneous population pharmacokinetic (PK) model for tablet and intravenous formulation was developed on the basis of a data set including Japanese data from healthy participants and treatment patients. The PK profiles and exposure distributions in Japanese patients were predicted and compared against foreign patients, that is, patients outside of Japan. Relationships between the post hoc posaconazole exposures and frequently observed clinical adverse events were evaluated. Although clinical trials for Japanese prophylaxis patients were not conducted, PK profiles in Japanese prophylaxis patients were predicted using the population PK model and demographic covariate information obtained from the published literature. Based upon the globally approved dosing regimen, posaconazole exposure distribution was predicted to be the highest in Japanese treatment patients, and generally similar between Japanese and foreign prophylaxis patients. Exposures in Japanese patients exceeded the efficacy target level (500 ng/mL). Safety profiles in Japanese treatment patients with the highest exposures were clinically acceptable without specific concerns to Japanese patients and appeared to have no relationship with posaconazole exposures. From PK, safety, and efficacy perspectives, the use of the same dosing regimen as in foreign patients was justified in Japanese prophylaxis and treatment patients.
Development of a polyurethane‐coated thin film solid phase microextraction device for multi‐residue monitoring of pesticides in fruit and tea beverages
Authors: Li Wenhui , Gu Ying , Liu Zikun , Hua Rimao , Wu Xiangwei , Xue Jiaying
Published: November 2022

A novel solid‐phase microextraction device coated with an efficient and cheap thin film of polyurethane was developed for trace determination of 13 widely used pesticides in fruit and tea beverages. A round‐shaped polyurethane film covering the bottom of a glass vial was fabricated as the sorbent to exhibit a superior capacity for preconcentrating target compounds and reducing matrix interferences. After optimization of the key parameters including the film type, extraction time, solution pH, ionic strength, desorption solvent, and conditions, this device allowed an efficient adsorption‐desorption cycle for the pesticides accomplished in one vial. Coupled with gas chromatography‐electron capture detection, the polyurethane‐coated thin film microextraction method was successfully established and applied for the analysis of real fruit and tea drinks, showing low limits of detection (0.001–0.015 μg/L), wide linear ranges (1.0–500.0 μg/L, r2 > 0.9931), good relative recoveries (77.2%–106.3%) and negligible matrix effects (86.1%–107.5%) for the target pesticides. The proposed approach revealed strong potential of extending its application by flexibly modifying the type or size of the coating film. This study provides insights into the enrichment of contaminants from complex samples using inexpensive and reusable microextraction devices that can limit the environmental and health impact of the sample preparation protocol.
Efficiency of visual selection of agronomic traits for soybean production in a protected environment
Authors: dos Santos Silva Francisco Charles , da Silva Amilton Ferreira , Gomes Bezerra André Ricardo , Costa Nobre Danúbia Aparecida , Rosa Daniele Piano , Sediyama Tuneo , Guimarães Claudinei Martins , Zuffo Alan Mario , da Silva Felipe Lopes , Soto Gonzales Hebert Hernán , Paucar Flores Luis Angel , Aguilera Jorge González
Published: November 2022

The objectives of this work were to evaluate the efficiency of visual selection in soybean under a protected environment, to determine if the ability of an evaluator to select visually depends on their experience with the crop, and to study the efficiency of visual selection of traits associated with productivity to obtain income gains. For that, three soybean populations (F3, F4, and F5) were used, composed of 20 families each, conducted in a greenhouse in a randomized block design, with three replicates and experimental units, two plants per pot. In these, five evaluators with different levels of experience with the crop made the visual selection for each plant. Evaluators differ in their ability to identify more productive plants, but this ability is not associated with the evaluator's experience with the crop. In the search for more productive soybean plants, the number of pods per plant is the characteristic that most assists visual selection, provided there is uniformity of experimental conditions and genetic variability.
Poly(acrylamide) Spheroids with Tunable Elasticity for Scalable Cell Culture Applications
Authors: Pieroth Stephanie , Heras‐Bautista Carlos O. , Hamad Sarkawt , Brockmeier Konrad , Hescheler Jürgen , Pfannkuche Kurt , Schmidt Annette M.
Published: November 2022

Many biological tissues resemble hydrogels and display Young's moduli below 50 kPa, corresponding to most cell types for the natural environmental conditions to grow. Contrastingly, conventional cell culture usually involves rigid substrates resulting in stiff priming effects, which are of increasing concern when it comes to scalable culturing of adhesive cells for regenerative purposes. As a solution to this problem, the employment of synthetic poly(acryl amide) (PAAm)‐based hydrogel beads with tissue‐matched mechanical properties are proposed as soft matrix for culture modes suitable for tidal bioreactor culture. Herein, technology is described to generate spherical, mm‐scaled PAAm hydrogel beads with adjustable, soft elastic properties that are produced by a continuous microfluidic approach. A simple and robust method is demonstrated to functionalize the spheroids with protein ligands, and the suitability of the matrix for cell cultivation is successfully demonstrated with three different cell types (murine mesenchymal stem cells, renal carcinoma cells, and human induced pluripotent stem cells) in model experiments and in a tidal bioreactor system. This versatile approach will pave the way toward novel cell culture systems based on bioreactors that allow scalable, soft carrier‐based expansion of cells on matrices with tissue‐matched elasticity.
Eigenvalue inequalities for the buckling problem of the drifting Laplacian
Authors: Qi Xuerong , Wang Zhaoxia
Published: November 2022

In this paper, we study the buckling problem of the drifting Laplacian on bounded domains in a complete Riemannian manifold with nonnegative ∞‐dimensional Bakry–Émery Ricci curvature. According to the property of the manifold, we obtain a family of trial functions. By making use of these trial functions, we derive a universal inequality of eigenvalues, which is independent of the domains.
Influence of image contrasts and reconstruction methods on the classification of multiple sclerosis‐like lesions in simulated sodium magnetic resonance imaging
Authors: Ruck Laurent , Mennecke Angelika , Wilferth Tobias , Lachner Sebastian , Müller Max , Egger Nico , Doerfler Arnd , Uder Michael , Nagel Armin M.
Published: November 2022

Purpose

To evaluate the classifiability of small multiple sclerosis (MS)‐like lesions in simulated sodium (23Na) MRI for different 23Na MRI contrasts and reconstruction methods.

Methods

23Na MRI and 23Na inversion recovery (IR) MRI of a phantom and simulated brain with and without lesions of different volumes (V = 1.3–38.2 nominal voxels) were simulated 100 times by adding Gaussian noise matching the SNR of real 3T measurements. Each simulation was reconstructed with four different reconstruction methods (Gridding without and with Hamming filter, Compressed sensing (CS) reconstruction without and with anatomical 1H prior information). Based on the mean signals within the lesion volumes of simulations with and without lesions, receiver operating characteristics (ROC) were determined and the area under the curve (AUC) was calculated to assess the classifiability for each lesion volume.

Results

Lesions show higher classifiability in 23Na MRI than in 23Na IR MRI. For typical parameters and SNR of a 3T scan, the voxel normed minimal classifiable lesion volume (AUC > 0.9) is 2.8 voxels for 23Na MRI and 19 voxels for 23Na IR MRI, respectively. In terms of classifiability, Gridding with Hamming filter and CS without anatomical 1H prior outperform CS reconstruction with anatomical 1H prior.

Conclusion

Reliability of lesion classifiability strongly depends on the lesion volume and the 23Na MRI contrast. Additional incorporation of 1H prior information in the CS reconstruction was not beneficial for the classification of small MS‐like lesions in 23Na MRI.
Childhood to adulthood: Accounting for age dependence in healthy‐reference distributions in 129Xe gas‐exchange MRI
Authors: Plummer Joseph W. , Willmering Matthew M. , Cleveland Zackary I. , Towe Christopher , Woods Jason C. , Walkup Laura L.
Published: November 2022

Purpose

Xenon‐129 (129Xe) gas‐exchange MRI is a pulmonary‐imaging technique that provides quantitative metrics for lung structure and function and is often compared to pulmonary‐function tests. Unlike such tests, it does not normalize to predictive values based on demographic variables such as age. Many sites have alluded to an age dependence in gas‐exchange metrics; however, a procedure for normalizing metrics has not yet been introduced.

Theory

We model healthy reference values for 129Xe gas‐exchange MRI against age using generalized additive models for location, scale, and shape (GAMLSS). GAMLSS takes signal data from an aggregated heathy‐reference cohort and fits a distribution with flexible median, variation, skewness, and kurtosis to predict age‐dependent centiles. This approach mirrors methods by the Global Lung Function Initiative for modeling pulmonary‐function test data and applies it to binning methods widely used by the 129Xe MRI community to interpret and quantify gas‐exchange data.

Methods

Ventilation, membrane‐uptake, red blood cell transfer, and red blood cell:membrane gas‐exchange metrics were collected on 30 healthy subjects over an age range of 5 to 68 years. A GAMLSS model was fit against age and compared against widely used linear and generalized‐linear binning 129Xe MRI analysis schemes.

Results

All 4 gas‐exchange metrics had significant skewness, and membrane‐uptake had significant kurtosis compared to a normal distribution. Age has significant impact on distribution parameters. GAMLSS‐binning produced narrower bins compared to the linear and generalized‐linear binning schemes and distributed signal data closer to a normal distribution.

Conclusion

The proposed “proof‐of‐concept” GAMLSS‐binning approach can improve diagnostic accuracy of 129Xe gas‐exchange MRI by providing a means of modeling voxel distribution data against age.
Time‐optimal L1/L2 norms optimal control for linear time‐invariant systems
Authors: Mai Heng , Chen Xuesong , Yin Zhaoyang
Published: November 2022

The theoretical properties of a novel time‐optimal / norms optimal control for linear time‐invariant systems are investigated. The ‐optimal control (or sparsest control) is converted to the time‐optimal / norms optimal control which can be solved efficiently. The proposed control is obtained via minimization of the time‐optimal / norms optimal control input along with the constraints on the state variable. Subsequently, by using the nonsmooth maximum principle, the uniqueness and continuity of the optimal solution of the time‐optimal / norms optimal control are proved. The superiority of the time‐optimal / norms optimal control is illustrated by numerical examples.
Nuclear pCHK1 as a potential biomarker of increased sensitivity to ATR inhibition
Authors: Sundararajan Vignesh , Tan Tuan Zea , Lim Diana , Peng Yanfen , Wengner Antje Margret , Ngoi Natalie Yan Li , Jeyasekharan Anand D , Tan David Shao Peng
Published: November 2022

Excessive genomic instability coupled with abnormalities in DNA repair pathways induces high levels of ‘replication stress’ when cancer cells propagate. Rather than hampering cancer cell proliferation, novel treatment strategies are turning their attention towards targeting cell cycle checkpoint kinases (such as ATR, CHK1, WEE1, and others) along the DNA damage response and replicative stress response pathways, thereby allowing unrepaired DNA damage to be carried forward towards mitotic catastrophe and apoptosis. The selective ATR kinase inhibitor elimusertib (BAY 1895344) has demonstrated preclinical and clinical monotherapy activity; however, reliable predictive biomarkers of treatment benefit are still lacking. In this study, using gene expression profiling of 24 cell lines from different cancer types and in a panel of ovarian cancer cell lines, we found that nuclear‐specific enrichment of checkpoint kinase 1 (CHK1) correlated with increased sensitivity to elimusertib. Using an advanced multispectral imaging system in subsequent cell line‐derived xenograft specimens, we showed a trend between nuclear phosphorylated CHK1 (pCHK1) staining and increased sensitivity to the ATR inhibitor elimusertib, indicating the potential value of pCHK1 expression as a predictive biomarker of ATR inhibitor sensitivity. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Numerical study on interactions of atmospheric plasmas and peptides by reactive molecular dynamic simulations
Authors: Ding Yun‐Han , Wang Xiao‐Long , Tian Shu‐Qi , Li Shan‐Rui , Li Lian , Li Quan‐Xin , Zhao Tong , Zhang Yuan‐Tao
Published: November 2022

Experimental observations have shown that peptides are chemically modified under plasma treatment, which impacts the function and lifetime of a protein. This paper investigates the interactions of reactive oxygen species (ROS) produced in atmospheric plasmas and peptides. Results show that the reactions typically start with the H abstraction from the side chain of amino acids. As the reactions continue, the introduction of O atoms is the most common reaction, and the formation of double C = C bonds, detachment of carboxyl groups, and cleavage of the ring are also observed. Moreover, the degree of oxidative modification of the peptides increases with increasing doses of ROS. This study reveals the formation and breaking of chemical bonds and the generation of new reactive groups in the structure of peptides under plasma treatment, which enables us to understand the mechanisms of plasma medicine deeply.
Seasonally distinct runoff–recharge partitioning in an alpine tundra catchment
Authors: Kershaw Geoffrey G. L. , English Michael C. , Wolfe Brent B.
Published: November 2022

Hydrological processes within the alpine tundra of the Taiga Cordillera ecozone in northwestern Canada are poorly understood, yet these areas receive more precipitation per unit area than lowlands and sustain late summer and winter flow in large river systems when contributions from other areas are reduced. The objective of this study was to quantify the spatial and temporal variability in streamflow and groundwater recharge within an alpine tundra basin with discontinuous permafrost and explore the potential impacts of climate change on the timing and intensity of these hydrological processes. Hydrometric and remote sensing methods were used to complete a water balance assessment of the study basin and compare spatial and seasonal differences in inputs, outputs, runoff ratio, and runoff–recharge partitioning during the 2019 open water season. During the freshet, the basin received large daily melt volumes and responded with highly efficient runoff. Evapotranspiration became the primary means of water loss in the early summer but declined as the summer progressed. During the summer, groundwater discharge exceeded precipitation inputs and sustained headwater subbasin streamflow. Groundwater recharge occurred primarily via glaciofluvial upland infiltration during the freshet and channel bed infiltration during the summer. The partitioning of basin outputs between runoff and groundwater recharge was highly seasonal, with a freshet ratio favoring runoff (0.83) while the early and late summer favored recharge (0.28 and 0.17, respectively). As climate change continues, higher air temperatures and greater precipitation are expected for the study basin. Longer open water seasons and declining permafrost extent within the study basin will result in a greater proportion of input water routed to storage and/or groundwater recharge instead of runoff. Shrubification and treeline expansion may also increase evaporative losses from alpine tundra areas, reducing both rapid runoff and delayed aquifer recharge contributions important for larger rivers at lower elevation.
Presence of cells in the polyaneuploid cancer cell (PACC) state predicts the risk of recurrence in prostate cancer
Authors: Trabzonlu Levent , Pienta Kenneth J. , Trock Bruce J. , De Marzo Angelo M. , Amend Sarah R.
Published: November 2022

Background

The nonproliferating polyaneuploid cancer cell (PACC) state is associated with therapeutic resistance in cancer. A subset of cancer cells enters the PACC state by polyploidization and acts as cancer stem cells by undergoing depolyploidization and repopulating the tumor cell population after the therapeutic stress is relieved. Our aim was to systematically assess the presence and importance of this entity in men who underwent radical prostatectomy with curative intent to treat their presumed localized prostate cancer (PCa).

Materials and Methods

Men with National Comprehensive Cancer Network intermediate‐ or high‐risk PCa who underwent radical prostatectomy l from 2007 to 2015 and who did not receive neoadjuvant treatment were included. From the cohort of 2159 patients, the analysis focused on a subcohort of 209 patients and 38 cases. Prostate tissue microarrays (TMAs) were prepared from formalin‐fixed, paraffin‐embedded blocks of the radical prostatectomy specimens. A total of 2807 tissue samples of matched normal/benign and cancer were arrayed in nine TMA blocks. The presence of PACCs and the number of PACCs on each core were noted.

Results

The total number of cells in the PACC state and the total number of cores with PACCs were significantly correlated with increasing Gleason score (p = 0.0004) and increasing Cancer of the Prostate Risk Assessment Postsurgical (CAPRA‐S) (p = 0.004), but no other variables. In univariate proportional hazards models of metastasis‐free survival, year of surgery, Gleason score (9–10 vs. 7–8), pathology stage, CAPRA‐S, total PACCs, and cores positive for PACCs were all statistically significant. The multivariable models with PACCs that gave the best fit included CAPRA‐S. Adding either total PACCs or cores positive for PACCs to CAPRA‐S both significantly improved model fit compared to CAPRA‐S alone.

Conclusion

Our findings show that the number of PACCs and the number of cores positive for PACCs are statistically significant prognostic factors for metastasis‐free survival, after adjusting for CAPRA‐S, in a case–cohort of intermediate‐ or high‐risk men who underwent radical prostatectomy. In addition, despite the small number of men with complete data to evaluate time to metastatic castration‐resistant PCa (mCRPC), the total number of PACCs was a statistically significant predictor of mCRPC in univariate analysis and suggested a prognostic effect even after adjusting for CAPRA‐S.
Review on Developments and Progress in Nickelate‐Based Heterostructure Composites and Superconducting Thin Films
Authors: Yang Xiaoping , Li Miao , Ding Zhenyu , Li Liangyu , Ji Ce , Wu Gang
Published: November 2022

In the past decade, the rapid development of modern heterointerface growth and characterization techniques has stimulated great effort to research and design the extraordinary physical properties of transition metal heterostructure composite materials. Here, new physics originates from the rearrangement of orbital, charge, spin, and lattice and the resulting rebalancing of their mutual interactions. In this paper, recent experimental and theoretical progress in the design, preparation, characterization, and physical property measurement of LaNiO3‐based heterostructure composites and the infinite‐layer Ni1 + nickelate superconducting thin films on (001) SrTiO3 substrate is reviewed, mainly by the methods of various X‐ray spectroscopy measurements, scanning transmission electron microscopy, and magneto‐transport measurements. In these materials, the electronic structure and orbital occupation around the Fermi level are modified, enabling nickelate‐based composite materials to exhibit new states of matter and physical phenomena, which are absent in the bulk constituents. Their confined structures, superconductivity, orbital polarization, charge transfer, electronic structures, magnetic properties, and X‐ray spectroscopic analysis, are therefore highlighted, aiming at understanding unconventional superconducting mechanisms and designing new high‐Tc superconducting low‐dimensional materials for device applications.
Robust integrated sequential covariance intersection fusion Kalman filters and their convergence and stability for networked sensor systems with five uncertainties
Authors: Gao Yuan , Deng Zili
Published: November 2022

For networked sensor systems (NSSs) with hard and soft sensors including five uncertainties, two universal approaches of solving the robust fusion estimation problems are presented. It includes an integrated sequential covariance intersection (SCI) fusion minimax robust Kalman filtering approach with cross‐covariance information and a generalized Lyapunov equation approach with four pairs of Lyapunov equations. Applying them, the robust local and SCI fused time‐varying and steady‐state Kalman filters are presented in the sense that their actual estimation error variances are guaranteed to have the corresponding minimal upper bounds. The equivalent batch SCI fusers are also presented. Their robustness and accuracy relations are proved, and the sensitivity of the SCI fuser with respect to the fused orders of sensors is analyzed. Applying the dynamic error system analysis method and the dynamic variance error system analysis method, a new convergence and absolute asymptotic stability theory of robust fusion Kalman filtering is presented. The classical Kalman filtering convergence and stability theory is developed. Compared with the original covariance intersection fuser, they significantly reduced the computational complexity and burden. Compared with the optimal and conservative SCI fusers, they significantly improved the robust accuracies. They are suitable to deal with asynchronous or random delayed data and are suitable for real‐time applications. A simulation applied to the two‐mass spring damper mechanical system shows their effectiveness.
Effect of Cu Vacancy on Cu3Si(001) Surface for the Synthesis of SiHCl3 by Hydrogenation of SiCl4:A DFT Study
Authors: Wang Huhu , Zheng Qing , Wang Yi , Ji Yuwen , Peng Wencai , Zhang Jinli , Zhang Jianshu , Liu Jichang
Published: November 2022

In this paper, the effect of Cu vacancy of Cu3Si(001) surface for the hydrogenation of silicon tetrachloride was systematically studied by density functional theory (DFT). The favorable adsorption sites and stable configurations of reaction species are obtained and three possible reaction paths of SiHCl3 formation were achieved by transition state search. For the perfect Cu3Si(001) surface(P), Path1 is the most favorable, with a reaction barrier of 158.15 kJ mol−1. For both the single Cu‐vacancy(SV) and double Cu‐vacancy Cu3Si(001) surface(DV), Path2 is the most favorable, with the reaction barriers of 130.07 kJ mol−1 and 124.81 kJ mol−1, respectively. The results reflect that the activation energy of the reaction decreased significantly with the increase of Cu‐vacancy on the Cu3Si(001) surface, which may be the reason for the higher catalytic activity of Cu3Si catalysts with smaller Cu−Si stoichiometric ratios. This study can provide a reasonable explanation for previously experimental observation and provide a guidance for future catalyst design.
Recent Advances in Rolling 2D TMDs Nanosheets into 1D TMDs Nanotubes/Nanoscrolls
Authors: Aftab Sikandar , Iqbal Muhammad Zahir , Rim You Seung
Published: November 2022

Transition metal dichalcogenides (TMDs) van der Waals (vdW) 1D heterostructures are recently synthesized from 2D nanosheets, which open up new opportunities for potential applications in electronic and optoelectronic devices. The most recent and promising strategies in regards to forming 1D TMDs nanotubes (NTs) or nanoscrolls (NSs) in this review article as well as their heterostructures that are produced from 2D TMDs are summarized. In order to improve the functionality of ultrathin 1D TMDs that are coaxially combined with boron nitride nanotubes and single‐walled carbon nanotubes. 1D heterostructured devices perform better than 2D TMD nanosheets when the two devices are compared. The photovoltaic effect in WS2 or MoS2 NTs without a junction may exceed the Shockley–Queisser limit for the above‐band‐gap photovoltage generation. Photoelectrochemical hydrogen evolution is accelerated when monolayer WS2 or MoS2 NSs are incorporated into a heterojunction. In addition, the photovoltaic performance of the WSe2/MoS2 NSs junction is superior to that of the performance of MoS2 NSs. The summary of the current research about 1D TMDs can be used in a variety of ways, which assists in the development of new types of nanoscale optoelectronic devices. Finally, it also summarizes the current challenges and prospects.
Linking Enhanced Kinetics of Electrocatalytic Oxygen Reduction Reaction with Increased Utilization of Active Sites in a Hierarchical Single‐Atom Catalyst
Authors: Li Lei , Xu Ming , Wang Yameng , Zhang Yanan , Li Yanyan , Li Fayan , Zeng Lin , Zhang Xinyu , Zheng Jiaxin , Zheng Zhiping
Published: November 2022

Single‐atom catalysts (SACs) are of tremendous current research due to maximized use of metal atoms and enhanced activity and selectivity for a great variety of chemical reactions. Hierarchically structured SACs have been explored to further increase the number and accessibility of active sites to realize the full potentials of SACs. However, though plausible‐sounding, these supposed advantages of hierarchically structured SACs are largely untested. The assumed enhancing effects on the formation of intermediates on and the overall reaction kinetics remain largely unknown. Herein is reported a Fe‐SAC with a hierarchical hollow structure (Fe/HH) that showed excellent activity in oxygen reduction reaction and proton exchange membrane fuel cell. Comparative experimental and computational studies with respect to Fe/SS—the counterpart of Fe/HH with a compact primary structure—reveal a significantly increased number of active sites and their utilization in Fe/HH as reflected by the facilitated formation of the rate‐determining‐step intermediate Fe‐OOH*. This work thus establishes unambiguously the connection between the increased utilization of active sites and the enhanced kinetics of the electrocatalytic reduction of oxygen.
Case study: Modifying repetitive behavior in a polar bear (Ursus maritimus)
Authors: Cambrelen Desirae , Nelson Slater Melissa
Published: November 2022

Stereotypic pacing in zoo‐housed carnivores has been intensively researched for decades, revealing that it is a subtly complex behavior with a highly variable etiology. While pacing can be an indicator of poor welfare, it can also be anticipatory in nature, or even have a completely different motivating operation. In this case study, the pacing of a zoo‐housed polar bear, “Tundra,” was maintained through inadvertent reinforcement. Baseline data revealed that in 86% of afternoon observations, Tundra paced when the door to shift him off‐exhibit was opened. Upon changing the contingencies of reinforcement, there was a change in his behavior; initially with a shift in time, and then a shift in duration. Using a strategy of Differential Reinforcement of an Incompatible behavior, the pacing bout duration significantly decreased from a median of 4 min 13 s to 2 min 26 s. Due to the potential for repetitive walking to negatively influence captive carnivore welfare and the high individual variability of this behavior, investigation into the ontogeny and motivation for these behaviors should continue.
Liability Annex to the Protocol on Environmental Protection to the Antarctic Treaty
Authors: Proelss Alexander , Steenkamp Robert C.
Published: November 2022

Twenty-nine States (the ‘Consultative Parties’), each with a substantial interest in Antarctica, collectively manage Antarctica through a system of consensus-based decisions. Traditionally, the Antarctic Treaty together with recommendations and measures adopted by the Antarctic Treaty Consultative Meetings (ATCM), the Convention on the Conservation of Antarctic Marine Living Resources (CAMLR Convention) and the Convention for the Conservation of Antarctic Seals (CCAS) form the basis of the Antarctic Treaty System. However, the Consultative Parties began to expand their environmental responsibilities in Antarctica in 1970 and agreed that they “should assume responsibility for the protection of the environment and the wise use of the Treaty area”. A major step in this regard was the addition to the Antarctic Treaty System of the Protocol on Environmental Protection to the Antarctic Treaty (PEPAT or the Protocol). Together with safeguarding free and peaceful scientific research, the Protocol incorporates the protection of the Antarctic environment into the Antarctic Treaty System. The Protocol has six annexes, with Annex VI (Liabilities Arising from Environmental Emergencies) being a product of the obligations contained in Articles 15 and 16 of the PEPAT. Specifically, Article 16 of the PEPAT states that:
Liability Under Part XI UNCLOS (Deep Seabed Mining)
Authors: Proelss Alexander , Steenkamp Robert C.
Published: November 2022

The part of the seabed and subsoil that is beyond national jurisdiction (hereafter, the Area) is regulated by Part XI of the United Nations Convention on the Law of the Sea (UNCLOS) as well as by the 1994 Implementation Agreement. The regime of deep seabed mining (DSM) in the Area foresees three phases: prospecting, exploration and exploitation. The exploration and exploitation phases involve several actors, including States, the International Seabed Authority (ISA or Authority) and private entities. Established under UNCLOS, the ISA is tasked with controlling and organising “activities in the Area, particularly with a view to administering the resources of the Area”. To date, the ISA has developed regulations related to exploration for minerals in the Area which set out the standard terms of exploration contracts as well as the requirements to apply for exploration rights. DSM in the Area is currently transitioning from the exploration phase into the exploitation phase, and the ISA is developing rules for the assessment and environmental management of future operations.