bluuebunny/crossref_metadata_2025 huggingface dataset:
Combination of Model for End‐Stage Liver Disease and Lactate Predicts Death in Patients Treated With Salvage Transjugular Intrahepatic Portosystemic Shunt for Refractory Variceal Bleeding
Authors: Walter Aurélie , Rudler Marika , Olivas Pol , Moga Lucile , Trépo Eric , Robic Marie Angèle , Ollivier‐Hourmand Isabelle , Baiges Anna , Sutter Olivier , Bouzbib Charlotte , Peron Jean Marie , Le Pennec Vincent , Ganne‐Carrié Nathalie , Garcia‐Pagán Juan Carlos , Mallet Maxime , Larrue Hélène , Dao Thong , Thabut Dominique , Hernández‐Gea Virginia , Nault Jean‐Charles , Bureau Christophe , Allaire Manon ,   on behalf of the Salvage TIPS Group
Published: May 2021

Background and Aims

Data about the prognosis of salvage transjugular intrahepatic portosystemic shunt (TIPS) using covered stents for refractory variceal bleeding caused by portal hypertension are scarce. We aimed to assess survival and to identify predictors of mortality in these patients.

Approach and Results

One hundred sixty‐four patients with cirrhosis from five centers treated with salvage TIPS between 2007 and 2017 were retrospectively divided into a derivation cohort (83 patients) and a validation cohort (81 patients). Comparisons were performed using the Mann‐Whitney and Fischer’s exact test. Six‐week overall survival (OS) was correlated with variables on the day of the TIPS using Kaplan‐Meier curves with log‐rank test and univariate/multivariate analyses using the Cox model. Eighty‐three patients were included in the derivation cohort (male, 78%; age, 55 years, alcohol‐associated cirrhosis, 88%; Model for End‐Stage Liver Disease [MELD], 19 [15‐27]; arterial lactate, 3.7 mmol/L [2.0‐8.3]). Six‐week OS rate was 58%. At multivariate analysis, the MELD score (OR, 1.064; 95% CI, 1.005‐1.126; P = 0.028) and arterial lactate (OR, 1.063; 95% CI, 1.013‐1.114; P = 0.032) were associated with 6‐week OS. Six‐week OS rates were 100% in patients with arterial lactate ≤2.5 mmol/L and MELD score ≤ 15 and 5% in patients with lactate ≥12 mmol/L and/or MELD score ≥ 30. The 81 patients of the validation cohort had similar MELD and arterial lactate level but lower creatinine level (94 vs 106 µmol/L, P = 0.008); 6‐week OS was 67%. Six‐week OS rates were 86% in patients with arterial lactate ≤2.5 mmol/L and MELD score ≤ 15 and 10% for patients with lactate ≥12 mmol/L and/or MELD score ≥ 30. In the overall cohort, rebleeding rate was 15.8% at 6 weeks, and the acute‐on‐chronic liver failure grade (OR, 1.699; 95% CI, 1.056‐1.663; P = 0.040) was independently associated with rebleeding.

Conclusions

After salvage TIPS, 6‐week mortality remains high and can be predicted by MELD score and lactate. Survival rate at 6 weeks was >85% in patients with arterial lactate ≤2.5 mmol/L and MELD score ≤ 15, while mortality was >90% for lactate ≥12 mmol/L and/or MELD score ≥ 30.
Association Between Proton Pump Inhibitor Use and Biliary Tract Cancer Risk: A Swedish Population‐Based Cohort Study
Authors: Kamal Habiba , Sadr‐Azodi Omid , Engstrand Lars , Brusselaers Nele
Published: May 2021

Background and Aims

Biliary tract cancer is a group of highly aggressive malignant disorders, yet risk factors are poorly understood. In this study, we aim to assess whether prolonged use of proton pump inhibitors (PPIs) increases the risk of incident biliary tract carcinoma in a nation‐wide population‐based cohort in Sweden.

Approach and Results

Using nation‐wide registries, we identified all adults who received maintenance PPIs (≥180 days) according to the Swedish Prescribed Drug Register from 2005 through 2012. Data on incident biliary tract cancer were retrieved from the Swedish Cancer, Death and Outpatient Registers. Risk of biliary tract cancer in persons who received PPI treatment was compared with the general population of the corresponding age, sex, and calendar year yielding standardized incidence ratios (SIRs) with 95% CIs. Of 738,881 PPI users (median follow‐up of 5.3 years), 206 (0.03%) developed gallbladder cancer and 265 (0.04%) extrahepatic and 131 (0.02%) intrahepatic bile duct cancer corresponding to SIRs of 1.58 (95% CI, 1.37‐1.81), 1.77 (95% CI, 1.56‐2.00), and 1.88 (95% CI, 1.57‐2.23), respectively. In sensitivity analyses restricted to persons without a history of gallstones or chronic liver or pancreatic diseases, SIRs were 1.36 (95% CI, 1.17‐1.57) and 1.47 (95% CI, 1.19‐1.80) for extra‐ and intrahepatic duct cancer, respectively. The risk remained higher than the corresponding general population with ≥5 years of PPIs use, ruling out confounding by indication.

Conclusions

 In this study, long‐term use of PPIs was associated with an increased risk of gallbladder, intrahepatic, and extrahepatic bile duct cancer compared with the general population.
Numerical solution for Sisko nanofluid flow through stretching surface in a Darcy–Forchheimer porous medium with thermal radiation
Authors: Upreti Himanshu , Joshi Navneet , Pandey Alok K. , Rawat Sawan K.
Published: May 2021

The heat transfer assessments in a Sisko nanofluid flow over a stretching surface in a Darcy–Forchheimer porous medium with heat generation and thermal radiation are studied. The numerical analysis technique is used to assess the governing nonlinear equations of the model. The influence of Forchheimer number, porosity, heat generation, radiation, and material parameters is examined. The outlines of Nusselt number and skin friction coefficient corresponding to pertinent parameters are revealed. The comparison of Nusselt number outlines of working fluid and Newtonian fluid is depicted. From the analysis, it has been examined that with the increase in Forchheimer number and material parameter values, heat transfer function decreases, whereas heat transfer characteristics of Sisko nanofluid increase with heat generation and material parameters. Moreover, working fluid velocity outlines depreciate when there is an increase in porosity parameter for both shear‐thinning and shear‐thickening. The comparison of this study with previous research has been conducted.
Soil moisture influenced the variability of air temperature and oasis effect in a large inland basin of an arid region
Authors: Hao Xingming , Hao Haichao , Zhang Jingjing
Published: May 2021

Soil moisture plays a significant role in land‐atmosphere interactions. Changing fractions of latent and sensible heat fluxes caused by soil moisture variations can affect near‐surface air temperature, thus influencing the oasis's cooling effect in arid regions. In this study, the framework for the evaporative fraction (EF) dependence on soil moisture is used to analyse the impacts of soil moisture variation on near‐surface air temperature and the oasis effect. The result showed that soil moisture's contribution rate to EF was significantly higher than that of EF to temperature. Under the interaction of temperature sensitivity to EF and EF to soil moisture, the ∂T/∂ϴ presented a similar tempo‐spatial variation with both of the above. It was most significant in oasis areas during summer (−1.676), while it was weaker in plain desert areas during the autumn (−0.071). In the study region, the effect of soil moisture variation on air temperature can reach 0.018–0.242 K for different land‐cover types in summer. The maximum variation of soil moisture in summer can alter air temperature by up to 0.386 K. The difference in temperature variability between the oasis and desert areas promoted the formation of the oasis effect. For different oasis, the multi‐year average oasis cold effect index (OCI) ranged from −1.36 to −0.26 K. In comparison, the average summer OCI ranged from −1.38 to −0.29 K. The lower bound of the cooling effect of oasis ranged from −4.97 to −1.69 K. The analysis framework and results of this study will provide a new perspective for further research on the evolution process of the oasis effect and water–heat balance in arid areas.
A feasibility study of a portable intraoperative specimen imaging X‐ray system based on carbon nanotube field emitters
Authors: Gupta Amar Prasad , Yeo Seung Jun , Mativenga Mallory , Jung Jaeik , Kim Wooseob , Lim Jongmin , Park Junyoung , Ahn Jeung Sun , Kim Seung Hoon , Chae Moon Shik , Yeon Yeong Heum , Kim Namkug , Ko Beom‐Seok , Ryu Jehwang
Published: May 2021

Abstracts

When breast cancer is surgically removed, a rim of normal tissue surrounding the tumor is also removed. This rim of normal tissue is called a margin and is studied by a pathologist to determine whether or not all tumor was removed. The pathologist achieves this by cutting the surgically removed tissue into thin slices and observing each slice under a microscope. This process is time‐consuming. Here, we investigate the feasibility of using a portable carbon nanotube (CNT)‐based X‐ray system for in situ detection of the presence of tumor cells in the surgical margin. Using the proposed technique, we successfully obtain X‐ray images, which clearly show cancer masses and microcalcifications. This feasibility study shows that portable CNT‐based X‐ray systems are promising candidates for next‐generation in situ pathological examinations.
Regional gene therapy for bone healing using a 3D printed scaffold in a rat femoral defect model
Authors: Kang H Paco , Ihn Hansel , Robertson Djani M , Chen Xiao , Sugiyama Osamu , Tang Amy , Hollis Roger , Skorka Tautis , Longjohn Donald , Oakes Daniel , Shah Ramille , Kohn Donald , Jakus Adam E , Lieberman Jay R
Published: May 2021

At the present time there are no consistently satisfactory treatment options for some challenging bone loss scenarios. We have previously reported on the properties of a novel 3D‐printed hydroxyapatite‐composite material in a pilot study, which demonstrated osteoconductive properties but was not tested in a rigorous, clinically relevant model. We therefore utilized a rat critical‐sized femoral defect model with a scaffold designed to match the dimensions of the bone defect. The scaffolds were implanted in the bone defect after being loaded with cultured rat bone marrow cells (rBMC) transduced with a lentiviral vector carrying the cDNA for BMP‐2. This experimental group was compared against 3 negative and positive control groups. The experimental group and positive control group loaded with rhBMP‐2 demonstrated statistically equivalent radiographic and histologic healing of the defect site (p > 0.9), and significantly superior to all three negative control groups (p < 0.01). However, the healed defects remained biomechanically inferior to the unoperated, contralateral femurs (p < 0.01). When combined with osteoinductive signals, the scaffolds facilitate new bone formation in the defect. However, the scaffold alone was not sufficient to promote adequate healing, suggesting that it is not substantially osteoinductive as currently structured. The combination of gene therapy with 3D‐printed scaffolds is quite promising, but additional work is required to optimize scaffold geometry, cell dosage and delivery.
Modifying the catalytic preference of alpha‐amylase toward n‐alkanes for bioremediation purposes using in silico strategies
Authors: Pinto Éderson Sales Moreira , Feltes Bruno César , Pedebos Conrado , Dorn Márcio
Published: May 2021

Since the beginning of oil exploration, whole ecosystems have been affected by accidents and bad practices involving petroleum compounds. In this sense, bioremediation stands out as the cheapest and most eco‐friendly alternatives to reverse the damage done in oil‐impacted areas. However, more efforts must be made to engineer enzymes that could be used in the bioremediation process. Interestingly, a recent work described that α‐amylase, one of the most evolutionary conserved enzymes, was able to promiscuously degrade n‐alkanes, a class of molecules abundant in the petroleum admixture. Considering that α‐amylase is expressed in almost all known organisms, and employed in numerous biotechnological processes, using it can be a great leap toward more efficient applications of enzyme or microorganism‐consortia bioremediation approaches. In this work, we employed a strict computational approach to design new α‐amylase mutants with potentially enhanced catalytic efficiency toward n‐alkanes. Using in silico techniques, such as molecular docking, molecular dynamics, metadynamics, and residue–residue interaction networks, we generated mutants potentially more efficient for degrading n‐alkanes, L183Y, and N314A. Our results indicate that the new mutants have an increased binding rate for tetradecane, the longest n‐alkane previously tested, which can reside in the catalytic center for more extended periods. Additionally, molecular dynamics and network analysis showed that the new mutations have no negative impact on protein structure than the WT. Our results aid in solidifying this enzyme as one more tool in the petroleum bioremediation toolbox.
Effect of miR‐630 expression on esophageal cancer cell invasion and migration
Authors: Liu Xi , Wu Wei , Zhang Shixin , Tan Wenfeng , Qiu Yang , Liao Kelong , Yang Kang
Published: May 2021

Background

Esophageal cancer (EC) is a common malignancy of the digestive tract, with high incidence. The objective of this study was to investigate the effect of miR‐630 expression on esophageal cancer (EC) cell invasion and migration.

Methods

The study group comprised 58 EC patients admitted to our hospital from April 2014 to 2016, and the control group comprised 60 healthy people visiting the hospital during the same period. miR‐630 levels in the peripheral blood of the two groups were compared, and the diagnostic value of miR‐630 for EC was analyzed. EC cell lines were used to evaluate the influence of miR‐630 expression on EC cell invasion and migration.

Results

miR‐630 expression was low in EC (p < 0.050). A receiver operating characteristic curve analysis showed that miR‐630 expression had a good diagnostic value for EC (p < 0.050) and was associated with disease course, pathological stage, differentiation degree, tumor metastasis, and patient prognosis and survival (p < 0.05). The ROC curve analysis showed that when cutoff value was 5.38, the diagnostic sensitivity and specificity of miR‐630 for EC were 73.33% and 76.67%, respectively; area under the ROC curve was 0.778 (95%CI 0.695–0.861). Transfection of miR‐630 into EC cells indicated that miR‐630 overexpression can reduce EC cell invasion and migration (p < 0.05). miR‐630 expression is low in EC and has good diagnostic value for EC.

Conclusion

miR‐630 overexpression can reduce EC cell invasion and migration, showing a possible key role of miR‐630 in EC diagnosis and treatment in the future.
FASCIN regulates actin assembly for spindle movement and polar body extrusion in mouse oocyte meiosis
Authors: Hu Lin‐Lin , Pan Meng‐Hao , Yang Feng‐Lian , Zong Zi‐Ao , Tang Feng , Pan Zhen‐Nan , Lu Xiang , Ren Yan‐Ping , Wang Jun‐Li , Sun Shao‐Chen
Published: May 2021

During mouse oocyte meiotic maturation, actin filaments play multiple roles in meiosis such as spindle migration and cytokinesis. FASCIN is shown to be an actin‐binding and bundling protein, making actin filaments tightly packed and parallel‐aligned, and FASCIN is involved in several cellular processes like adhesion and migration. FASCIN is also a potential prognostic biomarker and therapeutic target for the treatment of metastatic disease. However, little is known about the functions of FASCIN in oocyte meiosis. In the present study, we knocked down the expression of FASCIN, and our results showed that FASCIN was essential for oocyte maturation. FASCIN was all expressed in the different stages of oocyte meiosis, and it mainly localized at the cortex of oocytes from the GV stage to the MII stage and showed a similar localization pattern with actin and DAAM1. Depletion of FASCIN affected the extrusion of the first polar body, and we also observed that some oocytes extruded from the large polar bodies. This might have resulted from the defects of actin assembly, which further affected the meiotic spindle positioning. In addition, we showed that inhibition of PKC activity decreased FASCIN expression, indicating that FASCIN might be regulated by PKC. Taken together, our results provided evidence for the important role of FASCIN on actin filaments for spindle migration and polar body extrusion in mouse oocyte meiosis.
Perivascular cell‐derived extracellular vesicles stimulate colorectal cancer revascularization after withdrawal of antiangiogenic drugs
Authors: Huang Maohua , Chen Minfeng , Qi Ming , Ye Geni , Pan Jinghua , Shi Changzheng , Yang Yunlong , Zhao Luyu , Mo Xukai , Zhang Yiran , Li Yong , Zhong Jincheng , Lu Weijin , Li Xiaobo , Zhang Jiayan , Lin Jinrong , Luo Liangping , Liu Tongzheng , Tang Patrick Ming‐Kuen , Hong An , Cao Yihai , Ye Wencai , Zhang Dongmei
Published: May 2021

Antiangiogenic tyrosine kinase inhibitors (AA‐TKIs) have become a promising therapeutic strategy for colorectal cancer (CRC). In clinical practice, a significant proportion of cancer patients temporarily discontinue AA‐TKI treatment due to recurrent toxicities, economic burden or acquired resistance. However, AA‐TKI therapy withdrawal‐induced tumour revascularization frequently occurs, hampering the clinical application of AA‐TKIs. Here, this study demonstrates that tumour perivascular cells mediate tumour revascularization after withdrawal of AA‐TKI therapy. Pharmacological inhibition and genetic ablation of perivascular cells largely attenuate the rebound effect of CRC vascularization in the AA‐TKI cessation experimental settings. Mechanistically, tumour perivascular cell‐derived extracellular vehicles (TPC‐EVs) contain Gas6 that instigates the recruitment of endothelial progenitor cells (EPCs) for tumour revascularization via activating the Axl pathway. Gas6 silence and an Axl inhibitor markedly inhibit tumour revascularization by impairing EPC recruitment. Consequently, combination therapy of regorafenib with the Axl inhibitor improves overall survival in mice metastatic CRC model by inhibiting tumour growth. Together, these data shed new mechanistic insights into perivascular cells in off‐AA‐TKI‐induced tumour revascularization and indicate that blocking the Axl signalling may provide an attractive anticancer approach for sustaining long‐lasting angiostatic effects to improve the therapeutic outcomes of antiangiogenic drugs in CRC.
Human d‐lactate dehydrogenase deficiency by LDHD mutation in a patient with neurological manifestations and mitochondrial complex IV deficiency
Authors: Kwong Anna Ka‐Yee , Wong Sheila Suet‐Na , Rodenburg Richard J. T. , Smeitink Jan , Chan Godfrey Chi Fung , Fung Cheuk‐Wing
Published: May 2021

Background

d‐lactate, one of the isomers of lactate, exists in a low concentration in healthy individuals and it can be oxidized to pyruvate catalyzed by d‐lactate dehydrogenase. Excessive amount of d‐lactate causes d‐lactate acidosis associated with neurological manifestations.

Methods and Results

We report here a patient with developmental delay, cerebellar ataxia, and transient hepatomegaly. Enzyme analysis in the patient's skin fibroblast showed decreased mitochondrial complex IV activity. Using whole exome sequencing, we identified compound heterozygous variants in the LDHD gene, which encodes the d‐lactate dehydrogenase, consisting of a splice site variant c.469+1dupG and a missense variant c.752C>T, p.(Thr251Met) which are pathogenic and likely pathogenic respectively according to the American College of Medical Genetics and Genomics (ACMG) classification. The serum d‐lactate level was subsequently detected to be elevated (0.61 mmol/L, reference value: 0‐0.25 mmol/L).

Conclusion

This is the third report on LDHD mutations associated with d‐lactate elevation and was first reported to have decreased mitochondrial complex IV activity. The study provides more information on this rare metabolic condition but the association of LDHD deficiency with the clinical presentations requires further investigations.
Uncertainty of central China summer precipitation and related natural internal variability under global warming of 1 to 3°C
Authors: Li Zhibo , Chen Wen , Chen Shangfeng , Sun Ying , Qian Danlei
Published: May 2021

This study examines the response of summer precipitation over central China to global warming via the 50‐member large‐ensemble simulations conducted with the Canadian Earth System Model Version 2. It is found that the model ensemble mean summer precipitation stagnates under warming of 1 to 3°C, while precipitation increases rapidly over central China after 3°C of warming. This phenomenon indicates a strong nonlinear relationship between precipitation change and global warming, and the effects due to natural internal variability are more substantial than those of CO2 forcing in the early warming stage. We further examine the factors responsible for the large uncertainty of the precipitation projection over central China under warming of 1 to 3°C. For the members producing a precipitation increase over central China, the geopotential height and sea level pressure changes show a positive North Atlantic Oscillation–like trend pattern over the North Atlantic and a southeastward propagating atmospheric teleconnection from the North Atlantic to China. The atmospheric teleconnection from the mid–high‐latitude Atlantic to China provides diverging winds in the upper troposphere, causing ascending motion, and contributes to increased precipitation over central China. Besides, an El Niño‐like trend pattern of sea surface temperature (SST) is apparent in the preceding winter, which could contribute to the formation a low‐level anticyclone trend over the western North Pacific (WNP) in the subsequent summer via modulating the SST anomalies in the Indian and Atlantic oceans. The northward water vapour transport in the western part of the anticyclone also favours increased precipitation in central China. The above processes also apply to decreased precipitation, except with opposite signs of anomalies. This study highlights the combined contributions of mid–high‐latitude teleconnection and the WNP anticyclone related to tropical Pacific SST to the uncertainty in the projection of precipitation over central China.
The drivers of extreme rainfall event timing in Australia
Authors: Dey Raktima , Bador Margot , Alexander Lisa V. , Lewis Sophie C.
Published: May 2021

Australia experiences some of the world's most variable rainfall. Previous studies have mostly focused on understanding rainfall variability in terms of frequency and intensity. However, understanding the timing of when extreme rainfall occurs is crucial for seasonal prediction, although it largely remains unexplored. Here we investigate the timing of extreme rainfall in Australia and the spatial variability of this timing. This study examines how some of the large‐scale drivers, such as the El Niño–Southern Oscillation (ENSO) and the Interdecadal Pacific Oscillation (IPO), determine the timing and interannual variability of the timing of extreme rainfall in Australia. Our results show that there is a clear spatial north–south delineation in the season when extreme rainfall occurs in Australia, shown by a contour diagonally extending roughly from 21°S in the west of Australia to 33°S in the east. North of this contour, extreme rainfall usually occurs in austral summer, with the smallest interannual variability in the timing of extreme rainfall in this region. In the south, extreme rainfall usually occurs in autumn/winter months; however, the timing is highly variable. In southeast Australia (SEA), extreme rainfall can fall at any time of the year, which makes seasonal prediction extremely challenging for this region. Both observation and reanalysis data show that the area where extreme rainfall occurs in summer extends further south during negative IPO years. We also find that IPO and ENSO phases, and the interaction between them, play significant roles in both determining the timing of extreme rainfall and constraining the interannual variability, especially in SEA. We focus on SEA for further analysis as this region shows the greatest shift in seasonality of extremes in response to large‐scale variability. We conclude that studying the relationship between rainfall and large‐scale drivers is important for verification and improvement of the seasonal prediction of extreme rainfall.
Comparison of methods for filling in gaps in monthly rainfall series in arid regions
Authors: Abu Romman Zeinab , Al‐Bakri Jawad , Al Kuisi Mustafa
Published: May 2021

Full and reliable rainfall data are required for hydrological modelling, integrated water resource management, and planning. However, these data suffer from record gaps and sparse rain gage distribution, which implies that the use of an imputation method is crucial. This study aims to compare the outputs from 10 imputation methods that were used to infill missing rainfall depth data (MRD) in an arid Mediterranean region. Different statistical tests were used to assess the outputs from the imputation methods. The results showed that for MRD ranges between 5 and 20% the stepwise multiple linear regression (MLRsw) method was valid and produced the best results with a root‐mean‐square error (RSME) and mean absolute error (MAE) of less than 7 and 2 mm, respectively. This was followed by the Monte Carlo Markov chain expectation–maximization‐based multiple imputation (MI‐MCMC) method, which had an RSME and MAE of 1.01 and 0.08 mm, respectively, at 20% MRD. On the other hand, the use of satellite data for imputation (LR_GPCC estimates) was appropriate for MRD ranging between 10 and 15%, while the statistical and spatial method was suitable for MRD of less than 5%.
Intracochlear Electrocochleography and Speech Perception Scores in Cochlear Implant Recipients
Authors: Valenzuela Carla V. , Lichtenhan Jeffery T. , Lefler Shannon M. , Koka Kanthaiah , Buchman Craig A. , Ortmann Amanda J.
Published: May 2021

Objectives/Hypothesis

Previous studies have demonstrated that electrocochleography (ECochG) measurements made at the round window prior to cochlear implant (CI) electrode insertion can account for 47% of the variability in 6‐month speech perception scores. Recent advances have made it possible to use the apical CI electrode to record intracochlear responses to acoustic stimuli. Study objectives were to determine 1) the relationship between intracochlear ECochG response amplitudes and 6‐month speech perception scores and 2) to determine the relationship between behavioral auditory thresholds and ECochG threshold estimates. The hypothesis was that intracochlear ECochG response amplitudes made immediately after electrode insertion would be larger than historical controls (at the extracochlear site) and explain more variability in speech perception scores.

Study Design

Prospective case series.

Methods

Twenty‐two adult CI recipients with varying degrees of low‐frequency hearing had intracochlear ECochG measurements made immediately after CI electrode insertion using 110 dB SPL tone bursts. Tone bursts were centered at five octave‐spaced frequencies between 125 and 2,000 Hz.

Results

There was no association between intracochlear ECochG response amplitudes and speech perception scores. But, the data suggest a mild to moderate relationship between preoperative behavioral audiometric testing and intraoperative ECochG threshold estimates.

Conclusion

Performing intracochlear ECochG is highly feasible and results in larger response amplitudes, but performing ECochG before, rather than after, CI insertion may provide a more accurate assessment of a patient's speech perception potential.

Level of Evidence

4 Laryngoscope, 131:E2681–E2688, 2021
Cycles of grazing and agricultural activity during the historical period and its relationship with climatic and societal changes in northern China
Authors: Zhang Jun , Huang Xiaozhong , Zhang Shengrui , Ren Xiuxiu , Xiao Yulin , Wang Jiale , Xiang Lixiong , Xu Qinghai , Birks Harry John Betteley
Published: May 2021

The arable‐pastoral ecotone in northern China is ecologically fragile and the region has experienced substantial climatic variability, triggering population migrations, and the alternation of subsistence strategies during the historical period. However, the lack of continuous proxy records of arable and grazing activity has hampered our understanding of shifts in subsistence strategies and their relationship with climatic and societal changes. We obtained records of Sporormiella‐type spores and crop pollen from Gonghai Lake in northern China to reconstruct changes in cultivation and grazing intensity over the past approximately 2000 years. The results show that intensive grazing and cultivation occurred during the Sui and early‐middle Tang Dynasties (581–820 CE), when there was a relatively favourable climate, harmonious ethnic relations, and strong central government control. Conversely, weakened agricultural activity in the late Tang Dynasty (820–907 CE) corresponded to a deteriorating climate and frequent wars. High temperatures during the northern Song Dynasty (960–1127 CE) promoted the expansion of arable land in mountainous areas, whereas a cold climate and societal crises during the Era of Disunity (220–580 CE) and the Ming‐Qing Dynasties (1368–1912 CE) limited the expansion of cultivated land and there was a shift to grazing as a subsistence activity. Time‐series analysis reveals that the arable farming phases had a longer periodicity than the grazing phases, possibly because of the greater resilience of the former to climate change and the attachment of agriculturalists to their land. Our findings potentially help improve our understanding of the impact of land use on soil degradation.
Cannabinoid Use Among Liver Transplant Recipients
Authors: Yan Kathleen , Forman Lisa
Published: May 2021

The effect of cannabinoids on liver transplant outcomes is an area of active research. We aimed to investigate marijuana (MJ) and cannabidiol (CBD) use among liver transplant recipients at the University of Colorado Hospital (UCH), specifically prevalence, habits, and predictors of use. Liver transplant recipients followed at UCH with valid email addresses were sent an informed consent postcard and survey invitation. This exploratory survey was conducted using REDCap. IBM SPSS Statistics software was used for statistical analysis. Of 1227 recipients who were sent surveys, 538 people responded. On average, respondents were 59 years old, with 63.7% male and 81.7% White. Hepatitis C virus (HCV; 30.4%) and alcohol use (17.7%) were the most common etiologies of liver disease. Among respondents, 23.8% reported current MJ use. Methods of use included smoking (72.4%), ingestion (55.3%), and vaporization (31.7%). Top reasons for MJ use were recreation (56.5%), anxiety (54.8%), and pain (53.2%). Among respondents, 21.0% currently used CBD, usually in the form of creams or lotions (58.9%) and to relieve pain (84.9%) and anxiety (31.1%). In multivariable analysis, age (odds ratio [OR], 0.941; 95% confidence interval [CI], 0.923‐0.959; P < 0.001), diabetes mellitus (OR, 0.357; 95% CI, 0.171‐0.746; P = 0.01), HCV cirrhosis (OR, 3.949; 95% CI, 2.281‐6.835; P < 0.001), alcohol‐related cirrhosis (OR, 2.101; 95% CI, 1.202‐3.671; P = 0.01), and current tobacco use (OR, 2.918; 95% CI, 1.065‐7.990; P = 0.04) were significant predictors of MJ use. Our study shows that cannabinoid use after liver transplant is common. MJ use is associated with decreasing age, alcohol‐related and HCV cirrhosis, and tobacco use. Anxiety, pain, and recreation were top reasons for its use. Transplant teams should address reasons why their patients use MJ and CBD and develop programs to mitigate anxiety and pain after transplant. Further studies are needed to examine effects of cannabinoids on liver transplant outcomes.
Bilipschitz equivalence of polynomials
Authors: Bodin Arnaud
Published: May 2021

We study a family of two variables polynomials having moduli up to bilipschitz equivalence: two distinct polynomials of this family are not bilipschitz equivalent. However any level curve of the first polynomial is bilipschitz equivalent to a level curve of the second.
Intersection theorems for generalized weak KKM set‐valued mappings with applications in optimization
Authors: Balaj Mircea
Published: May 2021

In this paper, we introduce the concept of generalized weak KKM mapping that is more general than many others encountered in the KKM theory. Then, two previous intersection theorems of the author are extended from weak KKM mappings to generalized weak KKM mappings. Applications of these results to set‐valued equilibrium problems and minimax inequalities are given in the last two sections.
Feed‐forward activation of STAT3 signaling limits the efficacy of c‐Met inhibitors in esophageal squamous cell carcinoma (ESCC) treatment
Authors: Zhao Di , Chen Jie , Wang Yan , Zhang Lingyuan , Zhang Jing , Zhang Weimin , Fan Jiawen , Li Jinting , Zhan Qimin
Published: May 2021

c‐Hepatocyte growth factor receptor (Met) inhibitors have demonstrated clinical benefits in some types of solid tumors. However, the efficacy of c‐Met inhibitors in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, we discovered that c‐Met inhibitors induced “Signal Transducer and Activator of Transcription (STAT3)‐addiction” in ESCC cells, and the feedback activation of STAT3 in ESCC cells limits the tumor response to c‐Met inhibition. Mechanistically, c‐Met inhibition increased the autocrine of several cytokines, including CCL2, interleukin 8, or leukemia inhibitory factor, and facilitated the interactions between the receptors of these cytokines and Janus Kinase1/2 (JAK1/2) to resultantly activate JAKs/STAT3 signaling. Pharmacological inhibition of c‐Met together with cytokines/JAKs/STAT3 axis enhanced cancer cells regression in vitro. Importantly, combined c‐Met and STAT3 inhibitors synergistically suppressed tumor growth and promoted the apoptosis of tumor cells without producing systematic toxicity. These findings suggest that inhibition of the STAT3 feedback loop may augment the response to c‐Met inhibitors via the STAT3‐mediated oncogene addiction in ESCC cells.
Technical Note: Human tissue‐equivalent MRI phantom preparation for 3 and 7 Tesla
Authors: Woletz Michael , Roat Sigrun , Hummer Allan , Tik Martin , Windischberger Christian
Published: May 2021

Purpose

While test objects (phantoms) in magnetic resonance imaging (MRI) are crucial for sequence development, protocol validation, and quality control, studies on the preparation of phantoms have been scarce, particularly at fields exceeding 3 Tesla. Here, we present a framework for the preparation of phantoms with well‐defined T1 and T2 times at 3 and 7 Tesla.

Methods

Phantoms with varying concentrations of agarose and Gd‐DTPA were prepared and measured at 3 and 7 Tesla using T1 and T2 mapping techniques. An empirical, polynomial model was constructed that best represents the data at both field strengths, enabling the preparation of new phantoms with specified combinations of both T1 and T2. Instructions for three different tissue types (brain gray matter, brain white matter, and renal cortex) are presented and validated.

Results

T1 times in the samples ranged from 698 to 2820 ms and from 695 to 2906 ms, whereas T2 times ranged from 39 to 227 ms and from 34 to 235 ms for 3 and 7 Tesla scans, respectively. Models for both relaxation times used six parameters to represent the data with an adjusted R² of 0.998 and 0.997 for T1 and T2, respectively.

Conclusion

Based on the equations derived from the current study, it is now possible to obtain accurate weight specifications for a test object with desired T1 and T2 relaxation times. This will spare researchers the laborious task of trail‐and‐error approaches in test object preparation attempts.
Translation of the Chinese version of the Self‐Care for Aspiration Pneumonia Prevention Scale and its validation among Chinese community dwelling elderly with risk of dysphasia
Authors: Yang Zhen , Chen Fengmin , Zhang Yibo , Pan Sien , Lu Yingying , Zhang Huijun
Published: May 2021

Aim

To translate the Self‐Care for Aspiration Pneumonia Prevention Scale into the Chinese and validate its reliability and validity among community dwelling elderly with risk of dysphasia.

Design

A cross‐sectional survey.

Methods

A total of 430 elderly with risk of dysphasia were recruited. The reliability was measured by internal consistency, split half reliability, and test–retest reliability. The validity was evaluated by expert consultation and factor analysis.

Results

The translated scale had ideal reliability. The content validity index (S‐CVI) was 0.952. The 3‐factor structure, supported by the eigenvalues, total variance explained, and scree plot, was obtained by using exploratory factor analysis. And as a result of a confirmatory factor analysis, the model fitting indexes were all in the acceptable range. The Chinese version of the Self‐Care for Aspiration Pneumonia Prevention scale can contribute to clinical practice and education to improve self‐care for aspiration pneumonia prevention among elderly at risk of dysphasia.
The COVID‐19 pandemic and agricultural education: An exploration of challenges faced by teachers
Authors: McKim Aaron J. , Sorensen Tyson J. , Burrows Michelle
Published: May 2021

Exploring the challenges faced by agriculture teachers during the Spring 2020 semester brings to light the reality of teaching during the COVID‐19 pandemic. Further, understanding the challenges faced by teachers empowers the profession to make agricultural education more resilient to broader, social forces in the future. In this study, a national sample of agriculture teachers were asked to identify the three most pressing challenges they experienced during the COVID‐19 pandemic. Using qualitative research methods, eight challenge themes emerged: (a) Communication, (b) FFA (National FFA Organization, a student leadership organization previously named the “Future Farmers of America”), (c) Instructional Quality, (d) Program Facilities and Activities, (e) Supervised Agricultural Experiences (SAE), (f) Student Motivation, (g) Technology and the Internet, and (h) Work‐Life Balance. Using quasi‐statistical methods, the most commonly reported challenges were identified ‐ Instructional Quality, FFA, and Student Motivation. Analysis of all the challenges suggested permeation across each aspect of the three‐component model of agricultural education. Furthermore, many challenges appeared to be related to each other. Finally, analysis of the results illuminated responding teachers, and their students, each experienced the challenges brought about by COVID‐19 differently, including evidence of exacerbated educational inequality for students from lower income households.
Obesity and its implications on cerebral circulation and intracranial compliance in severe COVID‐19
Authors: Brasil Sérgio , Renck Alessandra Covallero , Taccone Fabio Silvio , Fontoura Solla Davi Jorge , Tomazini Bruno Martins , Wayhs Sâmia Yasin , Fonseca Sérgio , Bassi Estevão , Lucena Bruno , De Carvalho Nogueira Ricardo , Paiva Wellingson , Teixeira Manoel Jacobsen , Frade Costa Elaine Maria , Sá Malbouisson Luiz Marcelo
Published: May 2021

Objective

Multiple factors have been identified as causes of intracranial compliance impairment (ICCI) among patients with obesity. On the other hand, obesity has been linked with worst outcomes in COVID‐19. Thus, the hypothesis of severe acute respiratory syndrome (SARS) conducing to cerebral hemodynamic disorders (CHD) able to worsen ICCI and play an additional role on prognosis determination for COVID‐19 among obese patients becomes suitable.

Methods

50 cases of SARS by COVID‐19 were evaluated, for the presence of ICCI and cerebrovascular circulatory disturbances in correspondence with whether unfavorable outcomes (death or impossibility for mechanical ventilation weaning [MVW]) within 7 days after evaluation. The objective was to observe whether obese patients (BMI ≥ 30) disclosed worse outcomes and tests results compared with lean subjects with same clinical background.

Results

23 (46%) patients among 50 had obesity. ICCI was verified in 18 (78%) obese, whereas in 13 (48%) of 27 non‐obese (p = 0,029). CHD were not significantly different between groups, despite being high prevalent in both. 69% unfavorable outcomes were observed among obese and 44% for lean subjects (p = 0,075).

Conclusion

In the present study, intracranial compliance impairment was significantly more observed among obese subjects and may have contributed for SARS COVID‐19 worsen prognosis.
LDPE:PLA and LDPE:PLA:OMMT polymer composites: Preparation, characterization, and its biodegradation using Bacillus species isolated from dumping yard
Authors: Khan Mujahid S. , Dhavan Pratik P. , Ratna Debdatta , Sonawane Shriram S. , Shimpi Navinchandra G.
Published: May 2021

The focus of the present research is on the biodegradation of low density polyethylene (LDPE):polylactic acid (PLA) and LDPE:PLA:organo modified montmorillonite (OMMT) polymer nanocomposites. PLA was synthesized using the polycondensation method. The surface modification of nanomaterials is affected by various factors such as modifying agent, dispersion medium, and the dispersion of nanoparticles. Ultrasound cavitation technique improves the better dispersion of MMT in reaction mixture and enhances the interaction rate of a modifying agent with clay layered structure. A mixture of aminopropyltriethoxysilane and octadecyl amine was used for the surface modification of MMT. Polymer nanocomposite was prepared using the melt mixing method and used further for the biodegradation study. The mesophilic bacterium isolated from the dumping yard, identified by the 16rRNA technique, was capable of biodegradation of LDPE:PLA and LDPE:PLA:OMMT polymer nanocomposites. Isolated bacterial AP1 is 96.05% identical to the current MCCC1A02146 strain of Bacillus albus. After 50 days of incubation, the polymer nanocomposite sheet was characterized using Fourier transform infrared, X‐ray powder diffractometer, UV–Visible spectroscopy, Field Emission Scanning Electron Microscope (FESEM), etc. Further, LDPE:PLA30% (17.5%) and LDPE:PLA30%:OMMT4.5phr (19.20%), shows maximum percentage degradation. It has been observed that the addition of OMMT contributes to an enhancement in the polymer nanocomposite degradation because it has a large d‐spacing gap that is (21 Å) that enables the water to penetrate in the polymer matrix and increases the growth of bacteria within the polymer matrix. The highest change in biomass and change in extracellular protein content was found to be (39.11 mg/L and OD 0.38) LDPE:PLA30%:OMMT4.5phr composites. In addition, the mechanical properties decrease effectively after the incubation period, for LDPE:PLA 30% and LDPE:PLA30%:OMMT4.5phr.
Enhanced shielding of electromagnetic radiations with flexible, light‐weight, and conductive Ag‐Cu/MWCNT/rGO architected PVDF nanocomposite films
Authors: Rengaswamy Kumaran , Asapu Vinaya Kumar , Muthukaruppan Alagar , Sakthivel Dinesh Kumar , Venkatachalam Subramanian , Kannaiyan Dinakaran
Published: May 2021

High performance electromagnetic interference (EMI) shielding materials with ultra‐low density, excellent flexibility with comprehensive nature are highly demanded for wearable electronics, aeronautic, industries, medical, and research facilities. To address these requirements, the metal‐carbon based polymer composites have been fabricated by simple and scalable synthesis techniques. Combining the effect of multiple scattering with absorption, a high shielding efficiency of up to 29 dB for 0.1 mm is achieved. Selective architects of Ag/Cu nanoparticles along with two‐dimensional conducting sheets of MWCNT/rGO form multiple scattering structures in poly(vinylidene fluoride) matrix, prepared by facile solvent cast technique. The paper discusses the preparation of the composites, studies on morphological aspects, and concludes with a study on EMI shielding in the frequency region between 8 and 12 GHz.
Bilayer films of poly(ε‐caprolactone) electrosprayed with gum rosin microspheres: Processing and characterization
Authors: Pavon Cristina , Aldas Miguel , De La Rosa‐Ramírez Harrison , Samper María Dolores , Arrieta Marina Patricia , López‐Martínez Juan
Published: May 2021

Bilayer systems, consisting of electrosprayed gum rosin microspheres (eGR) and poly(ε‐caprolactone) (PCL), were prepared. First, the electrospraying processing conditions of GR in two different solvents, dichloromethane, and chloroform, were optimized. Various electrospraying polymeric solution flow rates and applied voltages were tested and morphologically analyzed in terms of particle size distribution and microspheres density. The conditions at which a homogeneous and narrow microspheres size distribution was achieved were chosen as the best for each solvent. The eGR was deposited onto a compression‐molded PCL film to obtain the bilayer systems. The bilayer systems were characterized by their visual appearance, microstructural analyses, thermal and mechanical performance, and surface wettability. It was determined that the mechanical and thermal behavior of PCL film was not affected due to the addition of the eGR microspheres layer. Meanwhile, the eGR layer considerably changes the surface color of the PCL film, reduces the film transparency, and produces a blocking effect in the UVB region and high blockage in the UVA region. In addition, the microspheres layer presents a tunable hydrophobicity depending on the solvent used, reaching values of ultrahydrophobic surfaces. Thus, the obtained result reveals a great potential to easily process bilayer systems with high interest in sustainable agricultural, packaging, and/or biomedical applications.
The structural language of crystalline polymers*
Authors: Lotz Bernard
Published: May 2021

In sharp contrast with their amorphous counterparts, crystalline polymers provide a wealth of information on their chain conformation, the packing of the chains in unit‐cells, the existence or not of mirror symmetric conformations, on the crystalline lamellae, on the folds linking the crystalline stems, and so forth. Three illustrations of these insights are presented here: (a) the orientation of polymer folds in crystalline lamellae, (b) the complete structural analysis of the alpha phase of isotactic polypropylene by a simple observation of the lamellar morphology, and (c) the so‐called lateral spread following secondary nucleation on the growth faces of a polymer crystal.
DFT insights into the structure, reactivity and radical scavenging activity of cycloartocarpesin
Authors: Tamafo Fouegue Aymard Didier , Tedongmo Hilaire , Abdoul Ntieche Rahman , Ghogomu Julius Numbonui
Published: May 2021

Daily increase in the number of patients suffering from illnesses due to reactive species has induced the permanent discovery and study of antioxidant compounds. The structure, reactivity, and antioxidant activity (AOA) of a phenolic compound named cycloartocarpesin (CAP), evaluated at DFT/B3LYP/6‐31 + G(d,p) level, is reported herein in the gas, pentyl ethanoate, and water phases. Bader topological analysis revealed that two of the three O‐H groups of CAP are involved in hydrogen bonds while the average local ionization energy (ALIE) and appropriate Fukui functions showed that electrons in the near vicinity of C7, C10, and C12are the least tightly held and can easily be attacked by radicals. Analysis of the transition state of the reaction between CAP and HOO•radical shows that the proton coupled electron transfer process is not favored. Moreover, analyses of electronic spectra calculated at TD‐DFT/B3LYP/6‐31 + G(d,p) has interestingly demonstrate the ability of CAP to filtrate UVA, UVB, and UVC, thus exhibiting a photo‐protective activity.