bluuebunny/crossref_metadata_2025 huggingface dataset:
Can Clinical Empathy Survive? Distress, Burnout, and Malignant Duty in the Age of Covid‐19
Authors: Anzaldua Adrian , Halpern Jodi
Published: March 2021

The Covid‐19 crisis has accelerated a trend toward burnout in health care workers, making starkly clear that burnout is especially likely when providing health care is not only stressful and sad but emotionally alienating; in such situations, there is no mental space for clinicians to experience authentic clinical empathy. Engaged curiosity toward each patient is a source of meaning and connection for health care providers, and it protects against sympathetic distress and burnout. In a prolonged crisis like Covid‐19, clinicians provide care out of a sense of duty, especially the duty of nonabandonment. We argue that when duty alone is relied on too heavily, with fear and frustration continually suppressed, the risk of burnout is dramatically increased. Even before Covid‐19, clinicians often worked under dehumanizing and unjust conditions, and rates of burnout were 50 percent for physicians and 33 percent for nurses. The Covid‐19 intensification of burnout can serve as a wake‐up call that the structure of health care needs to be improved if we are to prevent the loss of a whole generation of empathic clinicians.
A dynamic prognostic nomogram to predict the benefit from surgical treatment modality for patients with laryngeal squamous cell carcinoma
Authors: Chen Lin , Lin Gongbiao , Qian Jiawen , Chen Zhihong , Wu Xiaobo , Lin Jing , Chen Ying , Chen Qing , Zhuang Zhaocheng , Hong Yihong , Wang Jing , Liu Fengqiong , Wang Jing , He Baochang , Chen Fa
Published: March 2021

Background

Although nonsurgical treatment strategy is increasingly adopted in patients with locoregionally advanced laryngeal squamous cell carcinoma (LSCC), survival disparities were reported between surgical treatment modality and organ preservation protocols, highlighting the great importance for accurate patients' selection.

Method

This secondary analysis used data from the Surveillance, Epidemiology, and End Results database between 2010 and 2015 with follow‐up data up to 2018. We developed and validated a dynamic prognostic nomogram for overall survival (OS) in 4237 patients with LSCC and subgroup of 2087 patients with locoregionally advanced laryngeal squamous cell carcinoma (LALSCC). Based on the total risk score derived from the dynamic nomogram, two well‐matched risk groups (i.e., low‐ and high‐risk) were created via X‐tile software and 1‐to‐1 propensity score matching (PSM); surgical treatment modality was compared with nonsurgical one in each risk group.

Results

A more accurate and convenient dynamic prognostic nomogram based on age, marital status, T category, N category, M category, tumor size, and tumor differentiation was developed and validated, of which the predictive performance was superior to that of TNM staging system. For high‐risk LALSCC selected by the dynamic nomogram, after 1‐to‐1 PSM, significantly improved OS was observed in patients with receiving surgical treatment compared to those receipt of nonsurgical management (restricted mean survival time at 36‐month: 26.6 vs 22.7, p < 0.001; restricted mean survival time at 60‐month: 36.7 vs 31.0, p = 0.003).

Conclusion

We establish and validate a more accurate and convenient dynamic prognostic nomogram for patients with LSCC, which may predict the benefit from surgical treatment modality for patients with high‐risk LALSCC.
Prognostic value and therapeutic implications of nodal involvement in head and neck mucosal melanoma
Authors: Moya‐Plana Antoine , Mangin David , Blanchard Pierre , Obongo Rais , Casiraghi Odile , Bidault François , Temam Stéphane , Robert Caroline , Gorphe Philippe
Published: March 2021

Background

The prognostic significance of nodal involvement is not well established in head and neck mucosal melanoma (HNMM).

Methods

A retrospective, monocentric study was performed on 96 patients with HNMM treated between 2000 and 2017.

Results

At diagnosis, seventeen patients (17.8%) were cN1, with a higher risk for HNMM arising from the oral cavity (p = 0.01). cN status had no prognostic value in patients with nonmetastatic resectable HNMM. No occult nodal metastasis was observed in the cN0 patients after a nodal dissection (ND). The nodal recurrence rate was similar in the cN1 and the cN0 patients. No isolated nodal recurrences were noted. Among the patients who underwent a ND, no benefit of this procedure was noted.

Conclusions

cN1 status is not a prognostic factor in patients with resectable HNMM. Elective ND should not be systematically performed in cN0 HNMM.
Cytotoxicity and inflammatory effects in human bronchial epithelial cells induced by polycyclic aromatic hydrocarbons mixture
Authors: Wang Hong , Liu Jinren , Kong Qingbo , Li Liang , Gao Junhong , Fang Le , Liu Zhiyong , Fan Xiaolin , Li Cunzhi , Lu Qing , Qian Airong
Published: March 2021

Polycyclic aromatic hydrocarbons (PAHs) are the most common contaminants in the air pollutants. Inhalation exposure to PAHs could increase the risk of respiratory disease, cardiovascular disease and even cancer. However, the biotoxicity of multi‐component PAHs from atmospheric pollutants has been poorly studies. The main topic of this study was to investigate the PAHs mixture, which derived from atmospheric pollutants, induced toxic effects and inflammatory effects on human bronchial epithelial cells in vitro. The results showed that PAHs mixture could decrease the cell viability, increase the apoptosis rate, and induce cell cycle arrest at S‐phase. Furthermore, the expression of inflammatory factors IL‐1β and IL‐6 were increased and NF‐κB signaling pathway was activated in PAHs mixture‐treated cells. The findings of this study indicate that PAHs mixture‐induced cytotoxicity and inflammation may be related to intracellular ROS generation and to the activated NF‐κB signaling pathway.
Pregnancy-Related Change in pQCT and Bone Biochemistry in a Population With a Habitually Low Calcium Intake
Authors: Ó Breasail Mícheál , Ward Kate A , Schoenbuchner Simon M , Ceesay Mustapha , Mendy Michael , Jarjou Landing M , Moore Sophie E , Prentice Ann
Published: March 2021

In pregnancy, changes in maternal calcium (Ca) economy occur to satisfy fetal Ca demand. It is unclear whether maternal mineral reserves facilitate these requirements and no data exist from sub-Saharan Africa. The aim was to determine skeletal changes with peripheral quantitative computed tomography (pQCT) and bone biochemistry between early second and third trimesters. Pregnant rural Gambians aged 18 to 45 years (n = 467) participating in a trial of antenatal nutritional supplements (ISRCTN49285450) had pQCT scans and blood collections at mean (SD) 14 (3) and 31 (1) weeks’ gestation. Outcomes were pQCT: radius/tibia 4% total volumetric bone mineral density (vBMD), trabecular vBMD, total cross-sectional area (CSA), 33%/38% radius/tibia cortical vBMD, bone mineral content (BMC), total CSA; biochemistry: collagen type 1 cross-linked β-C-telopeptide (β-CTX), type 1 procollagen N-terminal (P1NP), parathyroid hormone (PTH), and 1,25(OH)2D. Independent t tests tested whether pooled or within-group changes differed from 0. Multiple regression was performed adjusting for age. Data for change are expressed as mean (confidence interval [CI] 2.5, 97.5%). Radius trabecular vBMD, cortical vBMD, and BMC increased by 1.15 (0.55, 1.75)%, 0.41 (0.24, 0.58)%, and 0.47 (0.25, 0.69)%. Tibia total and trabecular vBMD increased by 0.34 (0.15, 0.54)% and 0.46 (0.17, 0.74)%, while tibia cortical vBMD, BMC, and cortical CSA increased by 0.35 (0.26, 0.44)%, 0.55 (0.41, 0.68)% and 0.20 (0.09, 0.31)%, respectively. CTX, PTH, and 1,25(OH)2D increased by 23.0 (15.09, 29.29)%, 13.2 (8.44, 19.34)%, and 21.0 (17.67, 24.29)%, while P1NP decreased by 32.4 (−37.19, −28.17)%. No evidence of mobilization was observed in the peripheral skeleton. Resorption, although higher in late versus early gestation, was lower throughout pregnancy compared with non-pregnant non-lactating (NPNL) in the same community. Formation was lower in late pregnancy than in early, and below NPNL levels. This suggests a shift in the ratio of resorption to formation. Despite some evidence of change in bone metabolism, in this population, with habitually low Ca intakes, the peripheral skeleton was not mobilized as a Ca source for the fetus. © 2021 crown copyright . Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). The article published with the permission of the Controller of HMSO and the Queen's Printer of Scotland..
Prior loss of body mass index, low body mass index, and central obesity independently contribute to higher rates of fractures in elderly women and men
Authors: Zheng Rui , Byberg Liisa , Larsson Susanna C. , Höijer Jonas , Baron John A. , Michaëlsson Karl
Published: March 2021

We aimed to comprehensively evaluate the association of body composition with fracture risk using longitudinal data from a Swedish cohort of 44,366 women and men (mean age of 70 years) and a subcohort of 5022 women. We estimated hazard ratios (HRs) of fracture for baseline body mass index (BMI), BMI change during the prior 12 and 18 years, baseline waist-to-height ratio, total and regional distribution of fat and lean mass, with and without areal bone mineral density (BMD) adjustment. During follow-up (median 8.7 years), 7290 individuals sustained a fracture, including 4279 fragility fractures, of which 1813 were hip fractures. Higher baseline BMI and prior gain in BMI were inversely associated with all types of fracture. Lower fracture rate with higher baseline BMI was seen within every category of prior BMI change, whereas higher prior BMI gain conferred a lower rate of fracture within those with normal baseline BMI. Each standard deviation (SD) higher baseline waist-to-height ratio, after adjustment for BMI, was associated with higher rates of hip fracture in both women and men (HR 1.12; 95% CI, 1.05–1.19). In the subcohort (median follow-up 10 years), higher baseline fat mass index (FMI) and appendicular lean mass index (LMI) showed fracture-protective effects. After BMD adjustment, higher baseline BMI, total LMI, FMI, and higher prior BMI gain were associated with higher fracture rate. Baseline fat distribution also was associated with fracture rate; a 1-SD higher android to gynoid fat mass ratio in prior BMI gainers was associated with BMD-adjusted HRs of 1.16 (95% CI, 1.05–1.28) for any fracture and 1.48 (95% CI, 1.16–1.89) for hip fracture. This pattern was not observed among prior BMI losers. These findings indicate that for optimal fracture prevention, low baseline BMI, prior BMI loss and high baseline central obesity should be avoided in both women and men. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Superhydrophilic modification of APA‐TFC membrane surface by grafting QACs and salicylaldehyde units with PEG chains as the spacers
Authors: Wang Jia Jia , Liang Ya Qin , Fan Bian Hua , Zheng Yi Zhong , Zhang Tian Lin
Published: March 2021

The superhydrophilic modification of the aromatic polyamide (APA) thin‐film composite (TFC) membrane surface was achieved by densely grafting quaternary ammonium cations (QACs) and salicylaldehyde units with polyethylene glycol (PEG) chains as the spacers. The experimental results showed that the superhydrophilicity of the modified membrane surfaces was due to the abundant hydrophilic groups, such as PEG chains and QACs. The water fluxes of the modified membranes significantly increased by 36–39% compared with the hydrolyzed membrane, and the salt rejections slightly decreased. The accelerating chlorination tests showed that the modified membranes had the durable chemical stability in 7 × 105 ppm/hr chlorine aqueous solution at room temperature. Gram‐negative bacteria Escherichia coli and gram‐positive bacteria Staphyloccus aureus adhering to and growing on the modified membrane surface had been effectively prevented due to a combination of obstructing bacterial adhesion and contact‐killing during the incubation.
Phenotypic features of cancer cachexia‐related loss of skeletal muscle mass and function: lessons from human and animal studies
Authors: Martin Agnès , Freyssenet Damien
Published: March 2021

Cancer cachexia is a complex multi‐organ catabolic syndrome that reduces mobility, increases fatigue, decreases the efficiency of therapeutic strategies, diminishes the quality of life, and increases the mortality of cancer patients. This review provides an exhaustive and comprehensive analysis of cancer cachexia‐related phenotypic changes in skeletal muscle at both the cellular and subcellular levels in human cancer patients, as well as in animal models of cancer cachexia. Cancer cachexia is characterized by a major decrease in skeletal muscle mass in human and animals that depends on the severity of the disease/model and the localization of the tumour. It affects both type 1 and type 2 muscle fibres, even if some animal studies suggest that type 2 muscle fibres would be more prone to atrophy. Animal studies indicate an impairment in mitochondrial oxidative metabolism resulting from a decrease in mitochondrial content, an alteration in mitochondria morphology, and a reduction in mitochondrial metabolic fluxes. Immuno‐histological analyses in human and animal models also suggest that a faulty mechanism of skeletal muscle repair would contribute to muscle mass loss. An increase in collagen deposit, an accumulation of fat depot outside and inside the muscle fibre, and a disrupted contractile machinery structure are also phenotypic features that have been consistently reported in cachectic skeletal muscle. Muscle function is also profoundly altered during cancer cachexia with a strong reduction in skeletal muscle force. Even though the loss of skeletal muscle mass largely contributes to the loss of muscle function, other factors such as muscle–nerve interaction and calcium handling are probably involved in the decrease in muscle force. Longitudinal analyses of skeletal muscle mass by imaging technics and skeletal muscle force in cancer patients, but also in animal models of cancer cachexia, are necessary to determine the respective kinetics and functional involvements of these factors. Our analysis also emphasizes that measuring skeletal muscle force through standardized tests could provide a simple and robust mean to early diagnose cachexia in cancer patients. That would be of great benefit to cancer patient's quality of life and health care systems.
Honeycomb in the heart: A rare case of hydatid cyst of the interventricular septum
Authors: Singh Avneet , Negi Sunder , Kumar Rupesh , Toshkani Dheemta , Niyogi Subrashish Guha
Published: March 2021

The incidence of cardiac hydatid disease, caused by Echinococcus granulosus, is 0.5% to 2% in the sheep grazing areas of developing and under‐developed countries. The cyst can be present in the interventricular septum in 5% to 9% of the patients, along with conduction block or arrythmia. Intraoperative transesophageal echocardiography (TEE) can guide the surgeon in cyst localization and excision. This image review highlights the TEE findings in a young patient with multiple hydatid cysts of the interventricular septum, and the cyst membrane adhering to the septal tricuspid leaflet.
Ultrasound‐guided hydrostatic enema reduction of intussusception and confirmation with single abdominal radiograph in children
Authors: Karakuş Osman Z. , Sabuncu Serra , Ulusoy Oktay , Sarioglu Fatma Ceren , Güleryüz Handan , Ateş Oğuz , Hakgüder Gülce , Olguner Mustafa , Akgür Feza M.
Published: March 2021

Purpose

To detect false‐positive reduction results after ultrasound (US)‐guided hydrostatic intussusception reduction, we have incorporated water‐soluble contrast material to the enema fluid and confirmed the reduction with a single abdominal radiograph. We present the results of the combined imaging method for the reduction of intussusception in children.

Materials and Methods

The records of the patients who were treated for intussusception were analyzed retrospectively. Patients were divided into two groups: a US‐guided reduction group and a US‐guided reduction plus radiographic control group. The patient characteristics, symptoms, treatment methods, outcomes, and complications and follow‐up were analyzed.

Results

A total of 164 intussusception episodes were treated in 153 patients. Hydrostatic reduction of intussusception was performed in 59 patients in the US‐guided group and in 94 patients in the US‐guided plus radiographic control group. Recurrence rate in the US‐guided group was 15.7%, vs 3.5% in the US‐guided plus radiography group (P = .029). In the US‐guided plus radiographic control group, 5 (5.3%) false positive reductions under US guidance were determined by abdominal radiography.

Conclusion

In order to decrease false positive reduction rate and early recurrence, US‐guided intussusception reduction can be performed with saline plus water‐soluble contrast material and confirmation of reduction obtained with a single direct abdominal radiograph.
Rare case of human tail with tethered cord
Authors: Erdogdu Emre
Published: March 2021

Dorsal cutaneous appendage or human tail is a rare lesion with a variable prognosis depending on the presence of associated anomalies. In the absence of structural, chromosomal abnormalities and genetic syndromes, this cutaneous lesion may be a marker for underlying occult spinal dysraphism. The evaluation of the conus medullaris can help to detect of small a skin lesions related with low‐lying spinal cord conus. We report a case of the tail with tethered cord diagnosed with ultrasound at 21 weeks of gestation.
A reduction of the number of assays and turnaround time by optimizing polymerase chain reaction (PCR) pooled testing for SARS‐CoV‐2
Authors: Perivolaropoulos Christos , Vlacha Vasiliki
Published: March 2021

Early detection of the severe acute respiratory syndrome coronavirus 2 infection can decrease the spread of the disease and provide therapeutic options promptly in affected individuals. However, the diagnosis by reverse‐transcription polymerase chain reaction is costly and time‐consuming. Several methods of group testing have been developed to overcome this problem. The proposed strategy offers optimization of group testing according to the available resources by decreasing not only the number of the assays but also the turnaround time. The initial classification of the samples would be done according to the intention of testing defined as diagnostic or screening/surveillance, achieving the best possible homogeneity. The proposed stratification of pooling is based on branching (divisions) and depth (levels of re‐pooling) of the original group in association with the estimated probability of a positive sample. The dilutional effect of the grouped samples has also been considered. The margins of minimum and maximum conservation of assays of pooled specimens are calculated and the optimum strategy can be selected in association with the probability of positive samples in the original group. This algorithm intends to be a useful tool for group testing offering a choice of strategies according to the requirements.
Electronic monitoring of adherence to once‐daily and twice‐daily direct oral anticoagulants in patients with atrial fibrillation: Baseline data from the SMAAP‐AF trial
Authors: Shiga Tsuyoshi , Kimura Toshimi , Fukushima Noritoshi , Yoshiyama Yuji , Iwade Kazunori , Mori Fumiaki , Ajiro Yoichi , Haruta Shoji , Yamada Yuichiro , Sawada Emi , Hagiwara Nobuhisa ,   the SMAAP‐AF investigators
Published: March 2021

Background

Nonadherence diminishes the efficacy of direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation (NVAF). This report presents the baseline survey results regarding medication adherence among NVAF patients who were treated with once‐daily edoxaban or twice‐daily apixaban from a randomized control trial of the effect of an educational intervention on DOAC adherence.

Methods

We prospectively studied 301 NVAF patients who were treated with edoxaban (n = 175) or apixaban (n = 126) during the 12‐week observation period. Adherence was measured with an electronic monitoring system and is expressed as the percentage of days with the correct doses in the measurement period (days). Adherence to DOAC therapy was defined based on the standard threshold (≥80%) or a strict threshold (≥90%).

Results

Of the 301 patients, 33 had incomplete data or protocol deviations, leaving 268 patients (edoxaban 158 and apixaban 110) for the per‐protocol baseline analysis. There was no difference in adherence (threshold ≥80%) between the groups (edoxaban 95% vs apixaban 91%, P = .2), but there was a lower proportion of patients with strict adherence (threshold ≥90%) among apixaban users than among edoxaban users (edoxaban 87% vs apixaban 76%, P = .02). Multivariate analysis showed a negative relationship between apixaban use and an adherence rate ≥90% (odds ratio 0.49, 95% confidence interval [CI]: 0.25‐0.94).

Conclusions

Our study showed that the proportion of DOAC users with adherence (≥80%) did not differ between the groups, but the proportion of patients with strict adherence (≥90%) was lower among those using apixaban than among those using edoxaban.
Numerical study of effects of synoptic‐scale disturbances at high and low latitudes on mean summer precipitation over north‐eastern China and the Tibetan Plateau
Authors: Wang Chenyu , Yao Suxiang
Published: March 2021

We analysed the effects of synoptic‐scale disturbances (below periods <10 d) on summer precipitation over north‐eastern China and the Tibetan Plateau using observations and the regional climate model (RegCM4.6). Based on observed rainfall and ERA‐Interim reanalysis, singular value decomposition analysis showed that rainfall in these regions was significantly coupled with such disturbances at different latitudes in the troposphere. We further analysed this dynamic process by filtering out disturbances at different latitudes with respect to lateral boundary conditions. We then used sensitivity experiments to determine that the background specific humidity and wind (over periods >10 d) would be affected by the change of synoptic scale disturbances at lateral boundary. Weak mid‐high‐latitude (north of 30°N) disturbances also enhanced the intensity of mean meridional winds, leading to the northward transport of warm/wet advection that changed the thermal structure of the lower troposphere. The subsequent formation of divergence and high pressure in the upper troposphere caused increased precipitation in the two regions, though changes in low‐latitude (south of 30°N) disturbances had little effect. Further sensitivity experiments aimed at filtering out such disturbances to the west and north of the mid‐high‐latitude area revealed two propagation paths: disturbances in the west affected precipitation in both regions, while disturbances in the north mainly affected precipitation in north‐eastern China.
A 45‐year climatology of extratropical cyclone locations relative to upper‐level jet streak determined by an automatic procedure
Authors: Degirmendžić Jan
Published: March 2021

The main purpose of the analysis is to characterize the location of extratropical lows relative to the jet streaks over Europe and the North Atlantic. Algorithms are presented for jet streak detection and cyclone positioning relative to jet streaks. All time steps in the tracked cyclone lifetime together as well as cyclogenesis, maximum deepening and cyclolysis stages separately are examined. The analysis includes strong jet streaks (>50 ms−1) detected in 300 hPa wind fields in the winter period (1958–2002). The location of cyclones in the jet streak‐associated coordinate system is determined. The cyclone positions, situated near jet streak (<1,300 km), are depicted in the circular distribution diagrams and counted within 15° intervals and jet streak quadrants. The distribution of low‐pressure systems at the cyclogenesis and maximum deepening stages resembles the four‐quadrant model of upper‐level divergence: modal intervals are situated in the Left Front (LF) (primary mode: 45–60°) and the Right Rear (RR) (secondary mode: 195–210°) quadrants. Significant changes in cyclone counts at the LF‐LR and LR‐RR boundaries are likely to be a response to the divergence field aloft. Bimodality is distinctly pronounced in the case of cyclogenesis events and maximum deepening phases. The cyclolysis sites are unimodally distributed with maximum frequency in the Left Rear (LR) quadrant. The modal intervals of cyclogenesis and maximum deepening samples deviate towards the LF‐LR and RR‐LR boundary lines from the bisectors of the LF and RR quadrants, respectively. Such angular displacement is congruent with the shift of divergence‐convergence meridional dipoles in the entrance and exit region towards the cyclonic side of the jet stream. The incipient and maximum deepening stages of cyclones are located within the divergent quadrants in almost 80% of cases (of those near jet streaks). Nearly 60% of the cyclolysis events are situated in the convergent quadrants.
Knee joint unloading and daily physical activity associate with cartilage T2 relaxation times 1 month after ACL injury
Authors: Wellsandt Elizabeth , Kallman Tyler , Golightly Yvonne , Podsiadlo Daniel , Dudley Andrew , Vas Stephanie , Michaud Kaleb , Tao Matthew , Sajja Balasrinivasa , Manzer Melissa
Published: March 2021

Osteoarthritis (OA) is prevalent after anterior cruciate ligament (ACL) injury, but mechanismsunderlying its development are poorly understood. The purpose of this study was to determine if gait biomechanics and daily physical activity (PA) associate with cartilage T2 relaxation times, a marker of collagen organization and water content, 1 month after ACL injury. Twenty‐seven participants (15–35 years old) without chondral lesions completed magnetic resonance imaging, three‐dimensional gait analysis, and 1 week of PA accelerometry. Interlimb differences and ratios were calculated for gait biomechanics and T2 relaxation times, respectively. Multiple linear regression models adjusted for age, sex, and concomitant meniscus injury were used to determine the association between gait biomechanics and PA with T2 relaxation times, respectively. Altered knee adduction moment (KAM) impulse, less knee flexion excursion (kEXC) and higher daily step counts accounted for 35.8%–65.8% of T2 relaxation time variation in the weightbearing and posterior cartilage of the medial and lateral compartment (all p ≤ .011). KAM impulse was the strongest factor for T2 relaxation times in all models (all p ≤ .001). Lower KAM impulse associated with longer T2 relaxation times in the injured medial compartment (β = −.720 to −.901) and shorter T2 relaxation in the lateral compartment (β = .713 to .956). At 1 month after ACL injury, altered KAM impulse, less kEXC, and higher PA associated with longer T2 relaxation times, which may indicate poorer cartilage health. Statement of Clinical Significance: Gait biomechanics and daily PA are modifiable targets that may improve cartilage health acutely after ACL injury and slow progression to OA.
Covalent organic nanospheres modified magnetic nanoparticles for extraction of blood lipid regulators in water samples
Authors: Wan Tianfeng , Chen Zilin
Published: March 2021

Covalent organic nanospheres are new kind of nanospherical polymer with large specific surface area, uniform morphology, and excellent chemical and thermal stability. This material can be fabricated by a facile and rapid room temperature solution‐phase strategy. In this work, magnetic nanoparticles were attached to the surface of covalent organic nanospheres, and the obtained composites were used for the extraction of blood lipid regulators such as clofibrate and fenofibrate. These composites were characterized with Fourier‐transformed infrared spectroscopy, X‐ray photoelectron spectroscopy, and transmission electron microscopy. Several parameters that might affect the extraction efficiency including acetonitrile content, pH value, extraction time, and sample volume were investigated. Under optimum conditions, the proposed analytical method showed high extraction efficiency toward clofibrate and fenofibrate with enrichment factors between 60 and 83. This method exhibited outstanding analytical performance with wide linear range and excellent reproducibility and had low limits of detection in the range of 0.02–0.03 ng/mL. This method was also applied to the detection of clofibrate and fenofibrate in lake water samples, and good recoveries in the range of 92.6–112.6% was obtained.
Thermo‐Mechanical Fractional Injury Therapy for Facial Skin Rejuvenation in Skin Types II to V: A Retrospective Double‐Center Chart Review
Authors: Daniely Danny , Judodihardjo Harryono , Rajpar Sajjad F. , Mehrabi Joseph N. , Artzi Ofir
Published: March 2021

Background and Objectives

Thermo‐mechanical fractional injury (TMFI) therapy (Tixel®; Novoxel®, Netanya, Israel) is an innovative technology. Along with its drug delivery enhancement features, it is widely used for facial skin rejuvenation. Our study explores the beneficial effect of the Tixel® on the different features of facial skin rejuvenation along with patients′ satisfaction rate, aiming to suggest practical recommendations for an optimal aesthetic result.

Study Design/Materials and Methods

A retrospective chart review of 24 patients (20 women, 4 men, average age 56 years old) with skin types II–V who received 2 or 3 Tixel® treatments, 3–5 weeks apart in two medical centers (12 from Israel, 12 from the United Kingdom). Four experienced dermatologists compared standardized clinical photographs taken before each treatment and 3 months after the final treatment based on seven parameters that were set by 10 physicians and rated the difference on a scale of −1 to 4. Furthermore, epidemiology, treatment data, satisfaction, and safety were reviewed.

Results

Out of the seven parameters that were compared (blood vessels and erythema, skin complexion, periorbital wrinkles, pigmentation and toning, pore size, vitality, wrinkles, and laxity), all features demonstrated an overall improvement, with the greatest improvement demonstrated in skin complexion (2.1 ± 0.49) and periorbital wrinkling (2.09 ± 0.65) followed by vitality (1.7 ± 0.49). Side effects were transient, including erythema and hyperpigmentation, and the average downtime was 1.7 days.

Conclusion

TMFI is a safe and effective method for improving facial skin quality. Addressing patient′s expectations while maximizing the benefits of this novel technology will provide superior aesthetical results.
One‐Step Modification of Diacid‐Functional Polythioethers via Simultaneous Passerini and Esterification Reactions
Authors: Gungor Begum , Daglar Ozgun , Gunay Ufuk Saim , Hizal Gurkan , Tunca Umit , Durmaz Hakan
Published: March 2021

This study describes a one‐step Passerini and esterification reaction strategy for the first time at the macromolecular level in the literature. Polythioether (PT) including di‐tert‐butyl acetylenedicarboxylate (DTBADC) units is synthesized via a previously described rapid double thiol‐Michael addition polymerization method, followed by hydrolysis of tert‐butyl groups to produce dicarboxylic acid pendant polythioether (PH). PH is then utilized for postpolymerization modification via Passerini 3‐component reaction (Passerini‐ 3CR). Interestingly, it is found that on the course of Passerini‐3CR, the use of methanol (CH3OH) as a co‐solvent not only dissolves PH but also leads to the esterification reaction, which thereby further modifies the resultant polymer. This finding encourages the creation of a variety of ester functionality in the final polymer via Passerini‐3CR, by solely varying alcohols. The ratio of both ester and Passerini products in the modified polymers is monitored by 1H NMR analyses and a mechanistic aspect is also presented to product distribution. In addition, a monoacid containing polythioether (PMH) is prepared and used for the modification with Passerini‐3CR under the identical conditions described for PH, only Passerini product is obtained with no sign related to the ester product.
Ground state solutions for planar coupled system involving nonlinear Schrödinger equations with critical exponential growth
Authors: Wei Jiuyang , Lin Xiaoyan , Tang Xianhua
Published: March 2021

We consider the following two coupled nonlinear Schrödinger system:

where the coupling parameter satisfies 0 < λ(x) ≤ λ0 < 1 and the reactions f1, f2 have critical exponential growth in the sense of Trudinger–Moser inequality. Using non‐Nehari manifold method together with the Lions's concentration compactness and the Trudinger‐Moser inequality, we show that the above system has a Nehari‐type ground state solution and a nontrivial solution. Our results improve and extend the previous results.
A graded mesh refinement approach for boundary layer originated singularly perturbed time‐delayed parabolic convection diffusion problems
Authors: Kumar Kamalesh , Podila Pramod Chakravarthy , Das Pratibhamoy , Ramos Higinio
Published: March 2021

In this work, we consider a graded mesh refinement algorithm for solving time‐delayed parabolic partial differential equations with a small diffusion parameter. The presence of this parameter leads to boundary layer phenomena. These problems are also known as singularly perturbed problems. For these problems, it is well‐known that one cannot achieve a convergent solution to maintain the boundary layer dynamics, on a fixed number of uniform meshes irrespective of the arbitrary magnitude of perturbation parameter. Here, we consider an adaptive graded mesh generation algorithm, which is based on an entropy function in conjunction with the classical difference schemes, to resolve the layer behavior. The advantage of the present algorithm is that it does not require to have any information about the location of the layer. Several examples are presented to show the high performance of the proposed algorithm.
Fractional nonuniform multiresolution analysis in L2(ℝ)
Authors: Srivastava Hari M. , Shah Firdous A. , Lone Waseem Z.
Published: March 2021

To provide a significantly richer representation of non‐stationary signals appearing in various disciplines of science and engineering, we introduce a novel fractional nonuniform multiresolution analysis (FrNUMRA) on the spectrum Λ given by
, where
is an integer and r is an odd integer with
such that r and N are relatively prime. The necessary and sufficient condition for the existence of nonuniform wavelets of fractional order is derived and an algorithm is also presented for the construction of fractional NUMRA starting from a fractional low‐pass filter
with appropriate conditions. Besides, we provide a complete characterization for the biorthogonality of the translates of the scaling functions of two fractional nonuniform multiresolution analyses and the associated fractional biorthogonal wavelet families.
A philos‐type criterion to determine the oscillatory character of a class of neutral delay differential equations
Authors: Ramos Higinio , Bazighifan Omar
Published: March 2021

This paper is devoted to obtaining a new oscillation criterion for a class of neutral delay differential equations of the type wherem  ≥  4 is an even integer and . It should be noted here that the results obtained improve and complement those given by Xing et al. (2016). An example illustrating the applicability of the new criterion is presented.
Structural design of metal catalysts based on ZIFs: From nanoscale to atomic level
Authors: Zhang Kangjie , Shang Hailin , Li Bin , Wang Zhe , Lu Yuexiang , Wang Xiangke
Published: March 2021

Ultrasmall metal nanoparticles (MNPs) and atomically dispersed metal sites (ADMSs) exhibit excellent catalytic activity and selectivity. However, they tend to aggregate into large particles during synthesis and catalysis due to high surface free energy. Aiming to break out of this dilemma, zeolite imidazolate frameworks (ZIFs) have proved to be ideal substrates for stabilizing the ultrafine metal nanostructures. The stabilizing mode includes confining MNPs inside their pore structures and converting intrinsic metal nodes into coordinately unsaturated metal sites (i.e., ZIF‐confined metal catalysts). Furthermore, various MNPs and ADMSs can also be immobilized into ZIF‐derived porous carbon through high‐temperature pyrolysis (i.e., ZIF‐derived carbon‐supported metal catalysts). In brief, ZIFs and their derivatives have gradually emerged as good platforms for designing metal catalysts at nanoscale and even atomic level. In this review, recent progress in the structural analysis and synthetic strategies of metal catalysts supported by ZIFs and their derivatives is presented. Besides, current challenges and future directions of atomically dispersed metal catalysts are discussed. This article will provide valuable insights into rational design of metal catalysts with exquisite nanostructure and high catalytic performance to meet further material requirements in the catalytic field.
Magnetic resonance imaging to evaluate anterior pelvic prolapse: H line is the key
Authors: Rechi‐Sierra Kevin , Sánchez‐Ballester Francisco , García‐Ibáñez Joan , Pardo‐Duarte Paola , Flores‐DelaTorre Melchor , Monzó‐Cataluña Alba , López‐Alcina Emilio
Published: March 2021

Introduction

The aim of the study is to compare clinical staging of anterior pelvic prolapse with magnetic resonance imaging (MRI) staging, using the pubococcygeal line (PCL), the midpubic line (MPL), and the H line as reference lines. Moreover, we aim to analyze interrater reliability of each reference line.

Material and Methods

Forty‐two women with pelvic organ prolapse (POP) symptoms were studied using the pelvic organ prolapse quantification on physical examination. Two different observers calculated anterior POP using the three MRI reference lines, retrospectively. Agreement between MRI and clinical staging was estimated using Pearson correlation for the quantitative measurements and kappa index for the stages. Interrater reliability was estimated using the intraclass correlation coefficient (ICC).

Results

Correlation between physical examination and the H line was high by both observers (r = 0.86 and r = 0.76, p < 0.01). The correlation was lower using MPL (r = 0.76 and r = 0.65, p < 0.01). The results of comparing MRI staging and physical examination were: κ = 0.618 and κ = 0.602 for the H line, κ = 0.273 and κ = 0.267 for MPL and κ = −0.105 and κ = −0.140 for PCL. The results of interrater reliability were: ICC of 0.968 for the H line, ICC of 0.788 for MPL, and ICC of 0.737 for PCL.

Conclusion

Anterior POP staging using MRI H line as a reference presents a better agreement with clinical staging than PCL or MPL. The H line has better interrater reliability. The H line could replace the current lines.
Comparison between algebraic and matrix‐free geometric multigrid for a Stokes problem on adaptive meshes with variable viscosity
Authors: Clevenger Thomas C. , Heister Timo
Published: March 2021

Problems arising in Earth's mantle convection involve finding the solution to Stokes systems with large viscosity contrasts. These systems contain localized features which, even with adaptive mesh refinement, result in linear systems that can be on the order of 109or more unknowns. One common approach for preconditioning to the velocity block of these systems is to apply an Algebraic Multigrid (AMG) V‐cycle (as is done in the ASPECT software, for example), however, we find that AMG is lacking robustness with respect to problem size and number of parallel processes. Additionally, we see an increase in iteration counts with refinement when using AMG. In contrast, the Geometric Multigrid (GMG) method, by using information about the geometry of the problem, should offer a more robust option.Here we present a matrix‐free GMG V‐cycle which works on adaptively refined, distributed meshes, and we will compare it against the current AMG preconditioner (Trilinos ML) used in theASPECT1software. We will demonstrate the robustness of GMG with respect to problem size and show scaling up to 114,688 cores and 217 billion unknowns. All computations are run using the open‐source, finite element librarydeal.II.2
Whom you connect with matters for transparency: Board networks, political embeddedness, and information disclosure by Chinese foundations
Authors: Zhou Shuai , Zhu Jiangang , Zheng Guanghuai
Published: March 2021

Although the requirements for nonprofit transparency are increasing worldwide, the implementation of disclosure practices remains questioned. Drawing on social network theory, this study proposed that the size of and position in interlocking board networks can increase the propensity of foundations to promote transparency. It also hypothesized that political embeddedness, measured by the presence of powerful government officials, will negatively affect information disclosure. Using a short panel data set spanning 2,372 Chinese foundations, results showed that foundations with more board interlocks and occupying a brokerage position were more likely to implement information disclosure. However, when foundations were embedded with the government through officials, their transparency ratings were lower. It was further found that the effects of brokerage position and political embeddedness were more salient in public fundraising foundations than in nonpublic fundraising foundations. These findings therefore allude to the urgency that encouraging networking activities and democratizing the charitable field could heighten the diffusion of transparency.
Risk of COVID-19 in Patients with Cancer Receiving Immune Checkpoint Inhibitors
Authors: Klebanov Nikolai , Pahalyants Vartan , Murphy William S. , Theodosakis Nicholas , Zubiri Leyre , Klevens R. Monina , Kwatra Shawn G. , Lilly Evelyn , Reynolds Kerry L. , Semenov Yevgeniy R.
Published: March 2021

Objective

The aim of this study was to determine the rate of coronavirus disease-19 (COVID-19) among patients with cancer treated with immune checkpoint inhibitors (ICIs).

Materials and Methods

This was a retrospective study of 1,545 patients with cancer treated with ICIs between July 1, 2019, and February 29, 2020, and 20,418 age-, sex-, and cancer category-matched controls in a large referral hospital system. Confirmed COVID-19 case and mortality data were obtained with Massachusetts Department of Public Health from March 1 through June 19, 2020.

Results

The mean age was 66.6 years, and 41.9% were female. There were 22 (1.4%) and 213 (1.0%) COVID-19 cases in the ICI and control groups, respectively. When adjusting for demographics, medical comorbidities, and local infection rates, ICIs did not increase COVID-19 susceptibility.

Conclusion

ICIs did not increase the rate of COVID-19. This information may assist patients and their oncologists in decision-making surrounding cancer treatment during this pandemic.
Effects of different interface conditions on energy absorption characteristics of Al/carbon fiber reinforced polymer hybrid structures for multiple loading conditions
Authors: Ma Qi‐hua , Dong Fan , Gan Xue‐hui , Zhou Tianjun
Published: March 2021

The treatment of carbon fiber reinforced polymer (CFRP)–metal bond interface is very important for the practical application of CFRP‐reinforced metal structures in automobile, aviation, and other transportation vehicles. In this article, the effects of different interface connection conditions on the failure mode and energy absorption of hybrid tubes were studied by experimental and simulation methods. For this purpose, the two aspects metal surface treatment (sandblasting) and connection mode (socket, co‐curing, and secondary bonding) were used for adhesive joining. By observing the force–displacement curve, the energy absorption capacity of the hybrid tube under different interface connection conditions was quantified, and the performance was evaluated. The calculation results show that the interfacial connection conditions have different effects on the crashworthiness of the hybrid tube under different loading conditions. Among them, for axial crushing and transverse bending loads, the energy absorption characteristics of the hybrid tube can be effectively improved by sandblasting and cementing. Under the action of radial compression, although the roughness of the interface is increased by sandblasting, the energy absorption capacity is reduced rather than enhanced. In order to reveal the mechanism and make parameterized definitions of the interface characteristics, so as to effectively predict the finite element model is especially necessary. With the improvement of interface bond strength, its bearing limit distribution area also increases, and the corresponding deformation is also large, which eventually leads to more energy absorption under axial crushing and transverse bending loads. The increase in the interface connection strength has little effect on its crashworthiness under radial pressure.
Tribological and mechanical behaviors of mollusk shell‐ultrahigh molecular weight polyethylene bio‐composite
Authors: Sidia Besma , Bensalah Walid
Published: March 2021

This work is focused on the study of the tribological and mechanical properties of mollusk shell (MS)‐ultrahigh molecular weight polyethylene (UHMWPE) biocomposite against stainless steel. Wear tests were carried out on a reciprocating pin on disc apparatus. Tensile tests were achieved using a computerized universal traction machine, model EZ‐20 LLOYD. Rockwell hardness of the bio‐reinforced composite was carried out using an AFFRI universal hardness test. The coefficient of friction and wear rate were measured after tribological tests. From tensile tests, the ultimate strength, Young's modulus, fracture strain, and fracture strength were determined. It is found that wear tests of MS‐UHMWPE biocomposites achieved high tribological performance in terms of specific wear rate and coefficient of friction compared to pure UHMWPE. The mechanical properties of UHMWPE were enhanced by the addition of MS particles. The correlation between the mechanical and tribological properties of MS‐UHMWPE biocomposites was investigated. It is established that there is no solid confirmation of a strong correlation between the mechanical properties and the specific wear rate of MS‐UHMWPE biocomposites. However, the coefficient of friction gives a reasonable correlation with the hardness, fracture strain, fracture strength, and Young's modulus of the MS‐UHMWPE.
Prenatal diagnosis and postnatal management of congenital mesoblastic nephroma: Experience at a single center in China
Authors: Chen Yan‐Xiong , Huang Chao , He Qiu‐Ming , Wang Zhe , Huang Li , Wang Hai‐Yu , Mei Shan‐Shan , Chai Cheng‐Wei , Zhang Guang‐Lan , Zhong Wei , Li Dong‐Zhi
Published: March 2021

Objective

To review the prenatal and postnatal clinical characteristics and pathological subtypes, as well as the surgical outcome for congenital mesoblastic nephroma (CMN) cases.

Method

A retrospective review was performed in 11 cases with CMN prenatally diagnosed at a single center between 2015 and 2019. The clinical characteristics, surgical outcome, histopathology, and follow‐up were retrospectively obtained and reviewed.

Results

The median gestational age at which the sonographic diagnosis was made was 35 weeks. Polyhydramnios was found in four (36.4%) cases, and all resulted in a preterm birth. Nine infants had hypertension. Ten cases underwent radical nephrectomy, and one underwent radical nephrectomy and partial adrenalectomy. The pathological results showed that six tumors were classical variants, four mixed variants, and one was a cellular variant. Three cases presented as a stage I, eight as stage II, and no stage III or IV cases were diagnosed. All patients are alive so far. At a median follow‐up of 14 months, no local recurrence, or remote metastases were found.

Conclusion

The prognosis of prenatal CMN cases is excellent after early surgery.