bluuebunny/crossref_metadata_2025 huggingface dataset:
Direction of arrival estimation in multipath environments using deep learning
Authors: Harkouss Youssef
Published: May 2021

This article aims to present a novel direction of arrival (DOA) estimation strategy in multipath environments using deep learning. Eigen decomposition‐based algorithms, such as multiple signal classification (MUSIC), have high‐resolution DOA estimation performance, but they fail to work in the case of coherent signals. These algorithms require extensive computation and are difficult to implement in real time. Neural networks (multilayer perceptron [MLP] and radial basis function neural network [RBFNN]) are also applied to DOA estimation problem, and they are found to be faster than the conventional techniques, but they fail to ensure the desired accuracy in multipath environments when the training data set contains a huge number of samples and the number of incident signals was unknown. To enhance the DOA estimation performance, an efficient convolutional neural network (CNN)‐based smart antenna is proposed. This smart antenna is composed of a uniform linear array (ULA), an intelligent DOA estimator, and an efficient adaptive beamformer, and the space is decomposed into five space sectors. The intelligent DOA estimator contains six CNN networks. One network is used as a classifier to select one or more space sectors, and five networks are used to calculate the DOAs of unknown number of coherent or noncoherent incident signals that received in the selected space sectors. The simulation results demonstrate that the proposed DOA estimator enables reliable DOA estimation despite very challenging multipath environment, and the CNN substantially reduces the CPU time for the DOA estimation computations especially when the number of incident signals is large.
Quadrature spatial modulation‐aided single‐input multiple‐output‐media‐based modulation
Authors: Bamisaye Ayodeji J. , Quazi Tahmid
Published: May 2021

Single‐input multiple‐output media‐based modulation (SIMO‐MBM) improves the limitation of single‐input multiple‐output (SIMO) systems by minimizing the required number of antennas to achieve a high data rate and enhanced error performance. In this paper, we employ the quadrature dimension of the spatial constellation by decomposing the amplitude/phase modulation (APM) symbol into real and imaginary components similar to quadrature spatial modulation (QSM) to improve the overall error performance of the conventional SIMO‐MBM and to achieve a higher data rate. The average bit error probability of the proposed scheme is formulated using a lower bound approach and validated by the Monte Carlo (MC) simulation results obtained. Furthermore, the effect of the suboptimal mirror activation pattern selection using channel amplitude coupled with antenna correlatio n is examined for the proposed system. The MC simulation results achieved demonstrate a substantial improvement of 3.5 dB at 10 b/s/Hz withmrf = 2 and 7 dB at 12 b/s/Hz withmrf = 4 over the conventional SIMO‐MBM scheme.
Elevated urinary albumin concentration predicts worse clinical outcomes in hospitalized acute decompensated heart failure patients
Authors: Wang Yunhong , Zhao Xuemei , Zhai Mei , Fan Chaomei , Huang Yan , Zhou Qiong , Tian Pengchao , An Tao , Zhang Yuhui , Zhang Jian
Published: May 2021

Objective

To investigate the prognostic value of elevated urinary albumin concentration (UAC) in hospitalized acute decompensated heart failure (ADHF) patients.

Methods

We measured UAC at baseline in 1818 hospitalized ADHF patients who were admitted to our Heart Failure Center. All patients were followed up for a median period of 937.5 days. The primary endpoint was a composite of all‐cause death or heart transplantation (HTx) or left ventricular assist device (LVAD) implantation.

Results

In total, 41.5% of ADHF patients had albuminuria (UAC ≥ 20 mg/L). The median value of UAC was 15.5 mg/L. A total of 679 patients died or underwent HTx/LVAD during follow‐up. The median UAC was significantly lower in non‐HTx/LVAD survivors (14.3 mg/L) than in those who died or underwent HTx/LVAD (18.0 mg/L, P < 0.001). Compared with patients without albuminuria (reference, n = 1064), those with albuminuria had a 1.47‐fold higher risk of all‐cause death or HTx/LVAD (95% confidence interval [CI]:1.26–1.71, P < 0.001), with hazard ratios (HRs) of 1.42 (95% CI: 1.21–1.66) and 1.74 (95% CI: 1.33–2.26) in patients with microalbuminuria (20 mg/L ≤ UAC < 200 mg/L, n = 617) and macroalbuminuria (UAC ≥ 200 mg/L, n = 137), respectively (both P < 0.001). After adjustment for significant clinical risk factors, the albuminuria group had a higher risk of primary adverse events than the non‐albuminuria group (HR = 1.28, 95% CI: 1.09–1.50, P = 0.003), with HRs of 1.27 [95% CI: 1.07–1.49] and 1.36 [95% CI: 1.01–1.84] in patients with microalbuminuria and macroalbuminuria, respectively (P = 0.006 and P = 0.041). The adjusted risk of primary adverse events also increased with the degree of albuminuria in the test for trend (HR = 1.21, 95% CI: 1.06–1.37, P for trend = 0.004). In the subgroup analysis, albuminuria had a significantly greater prognostic value for patients with left ventricular ejection fraction ≥ 40%, eGFR ≥ 60 mL/min/1.73 m2, BUN/creatinine ratio ≥ 20 or NT‐proBNP < 2098 pg/mL.

Conclusion

The presence of albuminuria evaluated by UAC predicts adverse clinical outcomes in hospitalized ADHF patients.
Optimization of Ultrasound‐Assisted Alkali Neutralization in the Refining of Safflower Oil to Minimize the Loss of Bioactive Compounds
Authors: Ablay Özgür Devrim , Özdikicierler Onur , Saygın Gümüşkesen Aytaç
Published: May 2021

In this study, ultrasound‐assisted (UA) neutralization parameters are optimized using the response surface methodology to develop a novel alkali neutralization method based on the minimal refining concept. Sodium hydroxide (NaOH), magnesium oxide (MgO), and calcium hydroxide (Ca(OH)2) are used in both the traditional (TR) and UA neutralizations. Optimum probe depth, duration, and intensity levels are calculated as 3.7 cm, 25 s, and 54.3%, respectively, for UA neutralization with NaOH, which is more successful at free fatty acid (FFA) reduction and total phenolic content (TPC) retention than MgO and Ca(OH)2. Validation results of optimum conditions show that lowest average FFA content (0.29%) and highest average TPC (211.2 mg kg−1) are determined for the UA‐neutralized safflower oil samples. The comparison of all the neutralization experiments reveal that the UA neutralization under optimum conditions using NaOH reduced 82.8% of the FFA content, whereas the TR alkali neutralization reduced the FFA content at a maximum of only 47.8%.

Practical Applications: From the results, it can be inferred that the UA neutralization exhibits good performance in FFA content reduction and bioactive compound retention while offering a good solution within the concept of minimal refining.
Supercritical transesterification route for biodiesel production: Effect of parameters on yield and future perspectives
Authors: Singh Chandra Shekhar , Kumar Naveen , Gautam Raghvenrda
Published: May 2021

Catalyst‐free biodiesel production through supercritical transesterification is faster with the high conversion and a more environment‐friendly route than conventional catalyst transesterification. Improving and exploring the new possibilities in this alternative biodiesel production method by including newly available technology will lead us to a more sustainable future. In this paper, supercritical transesterification of biodiesel production has been reviewed in detail. The different parameters of this method, such as temperature, pressure, molar ratio, alcohol types, and residence time which affect the yielding and quality of fuel, have been reviewed. Besides, recycling the energy and suitable feedstock for this method has also been explored to reduce the intensive energy demand and operating cost. Furthermore, light has also thrown on co‐solvents effect on this method to reduce the extreme reaction conditions required. At last, the review concludes future recommendations in supercritical transesterification along with the challenges in energy integration and recycling.
Caution against examining the role of reverse causality in Mendelian Randomization
Authors: Lutz Sharon M. , Wu Ann Chen , Hokanson John E. , Vansteelandt Stijn , Lange Christoph
Published: May 2021

Recently, Mendelian Randomization (MR) has gained in popularity as a concept to assess the causal relationship between phenotypes in genetic association studies. An extension of standard MR methodology, the MR Steiger approach, has recently been developed to infer the causal direction between two phenotypes in prospective studies. Through simulation studies, we examined and quantified the ability of the MR Steiger approach to determine the causal direction between two phenotypes (i.e., effect direction). Through simulation studies, our results show that the MR Steiger approach may fail to correctly identify the direction of causality. This is true, especially in the presence of pleiotropy. We also applied the MR Steiger method to the COPDGene study, a case‐control study of chronic obstructive pulmonary disease (COPD) in current and former smokers, to examine the role of smoking on lung function. We have created an R package on Github called reverseDirection which runs simulations for user‐specified scenarios to examine when the MR Steiger approach can correctly determine the causal direction between two phenotypes in any user specified scenario. In summary, our results emphasize the importance of caution when the MR Steiger approach is used in to infer the direction of causality.
Spatiotemporal Phylodynamics of Hepatitis C Among People Who Inject Drugs in India
Authors: Clipman Steven J. , Mehta Shruti H. , Rodgers Mary A. , Duggal Priya , Srikrishnan Aylur K. , Saravanan Shanmugam , Balakrishnan Pachamuthu , Vasudevan Canjeevaran K. , Ray Stuart C. , Kumar Muniratnam S. , Quinn Thomas C. , Cloherty Gavin A. , Lucas Gregory M. , Solomon Sunil S.
Published: May 2021

Background and Aims

Implementing effective interventions for HCV requires a detailed understanding of local transmission dynamics and geospatial spread. Little is known about HCV phylodynamics, particularly among high‐burden populations, such as people who inject drugs (PWID).

Approach and Results

We used 483 HCV sequences and detailed individual‐level data from PWID across four Indian cities. Bayesian phylogeographic analyses were used to evaluate transmission hotspots and geospatial diffusion of the virus. Phylogenetic cluster analysis was performed to infer epidemiologic links and factors associated with clustering. A total of 492 HIV sequences were used to draw comparisons within the same population and, in the case of coinfections, evaluate molecular evidence for shared transmission pathways. Overall, 139/483 (28.8%) of HCV sequences clustered with a median cluster size of 3 individuals. Genetically linked participants with HCV were significantly younger and more likely to be infected with HCV subtype 3b as well as to live and inject close to one another. Phylogenetic evidence suggests likely ongoing HCV infection/reinfection with limited support for shared HIV/HCV transmission pathways. Phylogeographic analyses trace historic HCV spread back to Northeastern India and show diffusion patterns consistent with drug trafficking routes.

Conclusions

This study characterizes HCV phylodynamics among PWID in a low and middle‐income country setting. Heterogeneity and recent genetic linkage of HCV across geographically disparate Indian states suggest that targeted interventions could help prevent reimportation of virus through drug trafficking routes.
Interactions between aquatic vegetation, hydraulics and fine sediment: A case study in the Halswell River, New Zealand
Authors: Biggs Hamish J. , Haddadchi Arman , Hicks D. Murray
Published: May 2021

This paper contributes a field study of suspended sediment transport through aquatic vegetation. The study was run over a 3 month period which was selected to coincide with scheduled weed cutting activities. This provided the opportunity to obtain data points with no vegetation cover, as well as to investigate the effects of weed cutting on Suspended Sediment Concentrations (SSC), particle size distributions and river hydraulics. Aquatic vegetation cover was quantified through remote sensing with Unmanned Aerial Vehicles and biomass estimated from ground truth sampling. SSC was highly dependent on aquatic vegetation abundance, and the distance upstream that had been cleared of aquatic vegetation. The data indicates that fine sediment was being trapped and stored by aquatic vegetation, then likely remobilised after vegetation removal. Investigation of suspended sediment spatial dynamics illustrated changes in particle size distribution due to preferential settling of coarse particles within aquatic vegetation, for example D50 decreased from 36.08 μm to 15.64 μm after suspended sediment travelled 304.2 m downstream and passed ~3700 kg of aquatic vegetation biomass. Hydraulic resistance in the study reach (parameterized by Manning'sn) dropped by over 70% following vegetation cutting. Prior to cutting hydraulic resistance was discharge dependent (likely due to vegetation pronating at higher flows), while post cutting hydraulic resistance was approximately invariant of discharge. Aerial surveying captured interesting changes in aquatic vegetation cover prior to vegetation cutting, where some very dense regions of aquatic vegetation were naturally removed (without any high flow events) leaving behind unvegetated riverbed and fine sediment. The weed cutting boat had a lower impact on SSC than was originally expected, which indicates that it may offer a less damaging solution to aquatic vegetation removal in rivers than some other approaches such as mechanical excavation. This paper contributes valuable field data (which are generally scarce) on the research topic of flow‐vegetation‐sediment interactions, to supplement laboratory and numerical studies.
Transport energy consumption and carbon emissions: The role of urbanization towards environment in SAARC region
Authors: Mehmood Usman
Published: May 2021

Most of the existing literature on environmental assessment has concentrated on the linkages between energy consumption and CO2 emissions, and little attention has been paid to the association between transport energy consumption and CO2 emissions, which cannot be underestimated. Therefore, the present study contributes to the literature on the sustainable transport sector and urban settlements in South Asian Association for Regional Cooperation (SAARC) countries through an analysis of annual data from 1996 to 2015. Two unit root tests revealed mixed orders of integration for all variables. The Kao cointegration test revealed a strong association among the variables. The panel mean group (PMG) estimator confirmed that urbanization and regulatory quality improve air quality in the SAARC region. Gross domestic product (GDP) and the use of transport energy lower air quality. Considering the role of transport energy use in increasing CO2 emissions, this study provides some policy implications for the sustainable transport sector in SAARC countries. Integr Environ Assess Manag 2021;17:1286–1292. © 2021 SETAC

KEY POINTS

This work links transport energy consumption, urbanization, regulatory quality, and GDP in SAARC countries. Transport energy consumption is increasing CO2 emissions in SAARC countries. GDP and regulatory quality is decreasing CO2 emissions in SAARC countries. Important policy implications regarding the promotion of renewable energy in transport sector are recommended.
China's carbon emissions from the electricity sector: Spatial characteristics and interregional transfer
Authors: Fan Fengyan , Wang Yuying , Liu Qunyi
Published: May 2021

As a major carbon emitter, the electricity sector is crucial to the realization of China's emission reduction objectives. Existing studies focus mostly on the influencing factors, emission efficiency and low carbon development of carbon emissions in the electricity sector. Missing from the literature is an analysis of spatial characteristics of carbon emissions and the embodied carbon emission transfer caused by the separation of electricity production and consumption, which is the basis for assigning the responsibility for emission reduction. Thirty provinces in China were taken as research objects, and Moran's I index was adopted to analyze the spatial characteristics of the electricity sector's carbon emissions and carbon emission intensity. Based on multiregional input–output tables, we compared the transfer situation of China's provincial electricity carbon emissions in 2010 and 2015. The results demonstrate that, from 2010 to 2015, the electricity carbon emissions in 20 provinces increased, whereas the carbon emission intensity in 21 provinces decreased. Carbon emissions and carbon emission intensity of electricity in most provinces demonstrate positive spatial clustering characteristics. The total amount of carbon emission transfer in the electricity sector increased from 421.22 million tons in 2010 to 581.369 million tons in 2015, the number of net transfers out of areas increased from 13 to 15, and the number of net transfers into areas decreased from 16 to 15. The active degree of carbon emission transfer reveals the eastern region > the central region > the western region. Different emission reduction policies should be formulated based on the difference in resource endowment between the north and south. Provinces that transferred out large amounts of electricity carbon emissions should take greater responsibility for emission reduction. Integr Environ Assess Manag 2022;18:258–273. © 2021 SETAC

KEY POINTS

From 2010 to 2015, the electricity carbon emissions of most provinces in China increased, but the intensity of carbon emissions decreased, which indicates that the carbon emission efficiency of electricity consumption in most Chinese provinces has improved. The carbon emission efficiency of electricity consumption in China's provinces is conversely correlated to the level of regional economic development. From 2010 to 2015, the number of net transfer-out regions increased, mainly in the eastern region, whereas the number of net transfer-in regions decreased, mainly in the central and western regions with low economic development. The degree of activity in electricity carbon emission transfer reveals the eastern region > the central region > the western region.
Polydatin has anti‐inflammatory and antioxidant effects in LPS‐induced macrophages and improves DSS‐induced mice colitis
Authors: Chen Guangxin , Yang Ziyue , Wen Da , Guo Jian , Xiong Qiuhong , Li Ping , Zhao Liping , Wang Junping , Wu Changxin , Dong Lina
Published: May 2021

Polydatin (PD), a monocrystalline compound isolated from the root and rhizome of Polygonum cuspidatum, is widely used in inhibiting the inflammatory response and oxidative stress. PD has an anti‐inflammatory effect on colitis mice; however, information regulating the mechanism by which maintains the intestinal epithelium barrier is currently scarce. Here, we assessed the anti‐inflammatory and antioxidant of PD in lipopolysaccharide (LPS)‐induced macrophages in vitro, and explored its effects on inhibiting intestinal inflammation and maintaining the intestinal epithelium barrier in dextran sodium sulfate (DSS)‐induced colitis mice. Results showed that PD reduced the level of proinflammatory cytokines and enzymes, including tumor necrosis factor‐α, interleukin‐4 (IL‐4), IL‐6, cyclooxygenase‐2, and inducible nitric oxide synthase, in LPS‐induced macrophages, and improved the expression level of IL‐10. PD maintained the expression of tight junction proteins in medium (LPS‐induced macrophages medium)‐induced MCEC cells. Additionally, PD inhibited the phosphorylation of nuclear factor‐κB (NF‐κB), p65, extracellular signal‐regulated kinase‐1/2, c‐Jun N‐terminal kinase, and p38 signaling pathways in LPS‐induced macrophages and facilitated the phosphorylation of AKT and the nuclear translocation of Nrf2, improving the expression of HO‐1 and NQO1. Furthermore, PD ameliorated the intestinal inflammatory response and improved the dysfunction of the colon epithelium barrier in DSS‐induced colitis mice. Taken together, our results indicated that PD inhibited inflammation and oxidative stress, maintained the intestinal epithelium barrier, and the protective role of PD was associated with the NF‐κB p65, itogen‐activated protein kinases, and AKT/Nrf2/HO‐1/NQO1 signaling pathway.
SARS‐CoV‐2 congenital infection and pre‐eclampsia‐like syndrome in dichorionic twins: A case report and review of the literature
Authors: Abadía‐Cuchí Natalia , Ruiz‐Martínez Sara , Fabre Marta , Mateo Purificación , Remacha Sienes María , Ventura Faci Purificación , Bueno Sancho Jessica , Benito Rafael , Paules Cristina
Published: May 2021

Synopsis

Description of a case of probable transplacental transmission of severe acute respiratory syndrome coronavirus 2 to both twins and development of pre‐eclampsia‐like syndrome in the mother.
High‐security photoacoustic identity recognition by capturing hierarchical vascular structure of finger
Authors: Sun Mingman , Ma Yuanzheng , Tong Zhuangzhuang , Wang Zhiyang , Zhang Wuyu , Yang Sihua
Published: May 2021

Currently, most biometric methods mainly use single features, making them easily forged and cracked. In this study, a novel triple‐layers biometric recognition method, based on photoacoustic microscopy, is proposed to improve the security of biometric identity recognition. Using the photoacoustic (PA) dermoscope, three‐dimensional absorption‐structure information of the fingers was obtained. Then, by combining U‐Net, Gabor filtering, wavelet analysis and morphological transform, a lightweight algorithm called photoacoustic depth feature recognition algorithm (PADFR) was developed to automatically realize stratification (the fingerprint, blood vessel fingerprint and venous vascular), extracting feature points and identity recognition. The experimental results show that PADFR can automatically recognize the PA hierarchical features with an average accuracy equal to 92.99%. The proposed method is expected to be widely used in biometric identification system due to its high security.
Renal Contributions to Age‐Related Changes in Mineral Metabolism
Authors: Irsik Debra L , Bollag Wendy B , Isales Carlos M
Published: May 2021

Aging results in a general decline in function in most systems. This is particularly true with respect to the skeleton and renal systems, impacting mineral homeostasis. Calcium and phosphate regulation requires tight coordination among the intestine, bone, parathyroid gland, and kidney. The role of the intestine is to absorb calcium and phosphate from the diet. The bone stores or releases calcium and phosphate depending on the body's needs. In response to low plasma ionized calcium concentration, the parathyroid gland produces parathyroid hormone, which modulates bone turnover. The kidney reabsorbs or excretes the minerals and serves as the final regulator of plasma concentration. Many hormones are involved in this process in addition to parathyroid hormone, including fibroblast growth factor 23 produced by the bone and calcitriol synthesized by the kidney. Sclerostin, calcitonin, osteoprotegerin, and receptor activator of nuclear factor‐κB ligand also contribute to tissue‐specific regulation. Changes in the function of organs due to aging or disease can perturb this balance. During aging, the intestine cannot absorb calcium efficiently due to decreased expression of key proteins. In the bone, the balance between bone formation and bone resorption tends toward the latter in older individuals. The kidney may not filter blood as efficiently in the later decades of life, and the expression of certain proteins necessary for mineral homeostasis declines with age. These changes often lead to dysregulation of organismal mineral homeostasis. This review will focus on how mineral homeostasis is impacted by aging with a particular emphasis on the kidney's role in this process. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Fractures After Denosumab Discontinuation: A Retrospective Study of 797 Cases
Authors: Burckhardt Peter , Faouzi Mohamed , Buclin Thierry , Lamy Olivier ,   and the Swiss Denosumab Study Group
Published: May 2021

A rebound of osteoclast activity during the 2 years after a treatment or prevention of osteoporosis with denosumab (Dmab) leads to an increased risk of vertebral fractures (VFs). We attempted to identify the risk factors for these VF and to examine the protective role of bisphosphonates. For that, 22 specialists in Switzerland provided data of unselected patients, treated with denosumab for osteoporosis or breast cancer without metastases under aromatase inhibitors, who have received at least two injections of Dmab, with at least 1 year of follow-up after discontinuation. The questionnaire covered separately the periods before, during, and after Dmab treatment, and registered clinical, radiological, and lab data. For the analysis of the risk factors, the main outcomes were the time to the first VF after the treatment, the presence of multiple VFs (MVFs), and the number of VFs. The incidence of VF was 16.4% before, 2.2% during, and 10.3% after the treatment with Dmab. The risk of VF after Dmab discontinuation was associated with an increased risk of non-vertebral fractures. The pretreatment predictors of the post-treatment fracture risk were a parental hip fracture and previous VFs. Further risk factors appeared later, such as low total hip bone mineral density (BMD) during and after denosumab, increased bone resorption markers, and the loss of total hip BMD after the denosumab. Treatment with bisphosphonates, especially after Dmab, had a protective effect. Bisphosphonates given before Dmab did not further decrease the risk of VF in cases who got bisphosphonates after Dmab. This study shows that the risk of VF is poorly predictable before the prescription of denosumab. But during and after the treatment, bone resorption markers and BMD have a significant predictive value. Bisphosphonates after the treatment with denosumab are protective against VFs. © 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).
Active autophagy in cancer‐associated fibroblasts: Recent advances in understanding the novel mechanism of tumor progression and therapeutic response
Authors: Jena Bikash Chandra , Rout Lipsa , Dey Ankita , Mandal Mahitosh
Published: May 2021

Autophagy is primarily a homeostatic and catabolic process that is increasingly being recognized to have a pivotal role in the initiation and maintenance of cancer cells, as well as in the emergence of therapeutic resistance. Moreover, in the tumor microenvironment (TME) autophagy plays a crucial and sometimes dichotomous role in tumor progression. Recent studies show that during the early stages of tumor initiation, autophagy suppresses tumorigenesis. However, in the advanced stage of tumorigenesis, autophagy promotes cancer progression by protecting cancer cells against stressful conditions and therapeutic assault. Specifically, in cancer‐associated fibroblasts (CAFs), autophagy promotes tumorigenesis not only by providing nutrients to the cancerous cells but also by inducing epithelial to mesenchymal transition, angiogenesis, stemness, and metastatic dissemination of the cancer cells, whereas in the immune cells, autophagy induces the tumor‐localized immune response. In the TME, CAFs play a crucial role in cancer cell metabolism, immunoreaction, and growth. Therefore, targeting autophagy in CAFs by several pharmacological inducers like rapamycin or the inhibitor such as chloroquine has gained importance in preclinical and clinical trials. In the present review, we summarized the basic mechanism of autophagy in CAFs along with its role in driving tumorigenic progression through several emerging as well as classical hallmarks of cancer. We also addressed various autophagy inducers as well as inhibitors of autophagy for more efficient cancer management. Eventually, we prioritized some of the outstanding issues that must be addressed with utmost priority in the future to elucidate the role of autophagy in CAFs on tumor progression and therapeutic intervention.
Potassium channels and autism spectrum disorder: An overview
Authors: Cheng Peipei , Qiu Zilong , Du Yasong
Published: May 2021

Autism spectrum disorder (ASD) comprises a group of neurodevelopmental disorders characterized by impaired social interaction and communication, and restricted, repetitive patterns of behaviors, interests, or activities. It had been demonstrated that potassium channels played a key role in regulating neuronal excitability, which was closely associated with neurological diseases including epilepsy, ataxia, myoclonus, and psychiatric disorders. In recent years, a growing body of evidence from whole‐genome sequencing and whole‐exome sequencing had identified several ASD susceptibility genes of potassium channels in ASD subjects. Genetically dysfunction of potassium channels may be involved in altered neuronal excitability and abnormal brain function in the pathogenesis of ASD. This review summarizes current findings on the features of ASD‐risk genes (KCND2, KCNQ2, KCNQ3, KCNH5, KCNJ2, KCNJ10, and KCNMA1) and further expatiate their potential role in the pathogenicity of ASD.
Three‐dimensional study of the lingual papillae and their connective tissue cores in the Nile fox (Vulpes vulpes aegyptica) (Linnaeus, 1758)
Authors: Mahdy Mohamed A. A.
Published: May 2021

The Nile fox (Vulpes vulpes aegyptica) is the largest Egyptian fox being distributed in different geographical regions in Egypt. The current study aims to investigate the three‐dimensional features of the lingual papillae and their connective tissue cores (CTCs) in the Nile fox by using scanning electron microscopy. Five types of lingual papillae were present on the dorsal aspect of the tongue: filiform, conical, fungiform, vallate, and foliate. Generally, the filiform papilla consisted of a main papilla and several accessory processes emerged from its basal part. Filiform papillae differed in their length, shape, and number of accessory processes according to the region of the tongue. Two types of filiform CTCs were present; either conical‐shaped or consisted of a main core and several accessory cores. Two types of conical papillae and two types of conical CTCs were demonstrated; elongated triangular‐shaped and large conical‐shaped. In addition, two types of fungiform papillae were demonstrated; rounded‐shaped and elongated fungiform papillae. The fungiform CTCs were thick columnar in shape with several parallel vertical folds. Six vallate papillae were present, they were surrounded by a groove and either conical papillae or an annular pad. The surface of the vallate CTCs and their surrounding pad had small protrusions. The foliate papillae were represented by 5–6 laminae separated by grooves. The foliate CTCs appeared as oval grooves limited by laminar projections. Regional variations of the filiform papillae and the presence of three types of gustatory papillae suggest specialization of the Nile foxes' tongue to their omnivorous diet.
Equal access of COVID‐19 vaccine distribution in Africa: Challenges and way forward
Authors: Aborode Abdullahi T. , Olofinsao Oluwatosin A. , Osmond Ekwebelem , Batubo Abiokpoyanam P. , Fayemiro Omowonuola , Sherifdeen Onigbinde , Muraina Luqman , Obadawo Babatunde S. , Ahmad Shoaib , Fajemisin Emmanuel A.
Published: May 2021

The World Health Organization (WHO) in Africa and Africa Center Disease Control (Africa CDC) urge the international community and different countries in Africa to ensure sustainable and concrete action to ensure equal and easy access to the COVID‐19 vaccines, as different countries in Africa are still struggling to develop a safe and effective strategy to ensure equal vaccine distribution, if available. Africa CDC has called on the international community to come together to help Africa with COVID‐19 vaccines to make equal the vaccine distribution among African countries as many cannot afford the vaccine costs due to the level of poverty and other negative factors. The African Union has endorsed the need for Africa to develop a framework to actively engage in easy accessibility to COVID‐19 vaccines, which will allow different countries in Africa to take easy steps that will strengthen the local vaccine distribution system, building workforce skills and knowledge, and enrich outreach services in Africa. The article discusses the need for equal access in the distribution of COVID‐19 vaccines in Africa, the challenges, and the necessary recommendations that can help to mitigate these challenges.
A time to act and a time for restraint: Everyday sensegiving in the context of paradox
Authors: Benbenisty Yizhaq , Luria Gil
Published: May 2021

Using a mixed‐methods approach, this study examines how leaders' everyday sensegiving strategies shape followers' compliance with a paradoxical use‐of‐force policy. Building on performance data derived from 41 teams and interviews with their respective team leaders, our findings point to two sensegiving strategies: practical (connecting the policy to larger organizational goals) and internalization (connecting the policy to team members' personal norms, experiences, and values). We also identified a third communication strategy, which did not involve sensegiving: bureaucratic communication (ignoring the paradox and delivering the policy). Findings show that followers deviated less from the paradoxical policy when their leaders used either of the two sensegiving strategies (internalization and practical) compared with the bureaucratic strategy. The findings shed light on the interplay between sensegiving and leadership theories that relate to the dynamics of motivating followers in contexts of paradox, particularly meaning‐based leadership.
What Neanderthals and AMH ate: reassessment of the subsistence across the Middle–Upper Palaeolithic transition in the Vasco‐Cantabrian region of SW Europe
Authors: MarÍN‐Arroyo Ana B. , Sanz‐Royo Alicia
Published: May 2021

Recent research in northern Spain has revealed the disappearance of Neanderthal populations in the Vasco‐Cantabrian region a few millennia earlier than in eastern and southern Iberia and discovered a short period of overlap with modern humans, at least, in terms of radiocarbon dates. However, the causes of Neanderthal decline understood as a regional and temporal process remain open. Despite the abundance of technological studies, modern‐quality chronological dating, and the availability of archaeofaunal and palaeoenvironmental data, there is a lack of consensus about how climatic and environmental conditions could have affected ungulate prey and, therefore, Neanderthal subsistence strategies. In this paper, an analytical summary of the archaeofaunal and taphonomic data available for the Vasco‐Cantabrian region, combined with the most recent chronological evidence, present general knowledge about animal biogeography and ecology during the Middle–Upper Palaeolithic transition, and provides an interpretation of the behaviour of both human species in the region. This work reviews the palaeomammal community of animals represented in the record as exploited by human groups in several caves and rock shelters and pointing to continuing lacunae in knowledge. Further research is needed to verify and potentially explain the apparent hominin population gap and the ultimate fate of the Neanderthals.
Case‐specific three‐dimensional hologram with a mixed reality technique for tumor resection in otolaryngology
Authors: Mitani Sohei , Sato Eriko , Kawaguchi Naoto , Sawada Shun , Sakamoto Kayo , Kitani Takashi , Sanada Tomoyoshi , Yamada Hiroyuki , Hato Naohito
Published: May 2021

Objective

We report our first experience of using a case‐specific three‐dimensional (3D) hologram for tumor resection in otolaryngology to show the proof of concept. In addition, a questionnaire was administered to assess the usefulness of the mixed reality technique in otolaryngology.

Methods

A case‐specific 3D hologram was developed from enhanced images of dynamic computed tomography, with reference to contrast‐enhanced magnetic resonance images, and used for preoperative planning and intraoperative image reference. To evaluate the usefulness of the 3D hologram with head mount displays (HMDs), 18 attendings and resident otolaryngologists completed a questionnaire with the Likert scale.

Results

The case‐specific 3D hologram on HMDs was successfully used by means of easy gesture‐handling without any monitors preoperatively and intraoperatively. The experience of picturing the tumor localization and evaluating the surgical approach was statistically better using the 3D hologram on HMDs than using the computer images (P < .01). Similarly, the holograms were observed to be better for intraoperative application and surgical education than computer images (P < .01).

Conclusion

We demonstrated the use of a case‐specific 3D hologram for tumor resection in otolaryngology. The technology may be useful for preoperative planning and intraoperative image reference, especially for challenging cases, and surgical education.

Level of Evidence

NA.
Milk Polar Lipids Supplementation to Obese Rats During Pregnancy and Lactation Benefited Skeletal Outcomes of Male Offspring
Authors: Han Lihua , Du Min , Ren Fazheng , Mao Xueying
Published: May 2021

Scope

Dietary intervention to obese dams during pregnancy and lactation period provides avenues for improving metabolic profiles of the offspring. In the current study, the effects of polar lipids‐enriched milk fat globule membrane (MFGM‐PL) supplementation to obese dams during pregnancy and lactation on the skeletal outcomes of male offspring are investigated.

Methods and Results

MFGM‐PL is supplemented to obese rats induced by high‐fat diet during pregnancy and lactation at a dose of 400 mg kg‐1 body weight. Results show that maternal MFGM‐PL supplementation significantly ameliorates the stunted skeletal growth of male offspring at weaning. In adulthood offspring, maternal MFGM‐PL supplementation protects against high‐fat diet (HFD)‐induced bone microstructure degeneration and bone marrow adipocyte accumulation. Further investigation shows that maternal supplementation of MFGM‐PL significantly ameliorates insulin resistance and increases the mRNA expression of growth hormone releasing hormone (GHRH) in the hypothalamus of HFD offspring. The growth hormone (GH)/insulin‐like growth factor‐1 (IGF‐1) axis is subsequently enhanced in MFGM‐PL + HFD offspring, contributing to the beneficial skeletal outcomes.

Conclusion

The findings suggest that maternal MFGM‐PL supplementation of HFD dam during pregnancy and lactation shows desirable effects on fetal skeletal development, with lasting beneficial programming impacts on skeletal outcomes of offspring.
Moderate Folic Acid Supplementation in Pregnant Mice Results in Altered Methyl Metabolism and in Sex‐Specific Placental Transcription Changes
Authors: Luan Yan , Leclerc Daniel , Cosín‐Tomás Marta , Malysheva Olga V. , Wasek Brandi , Bottiglieri Teodoro , Caudill Marie A. , Rozen Rima
Published: May 2021

Scope

Many pregnant women have higher folic acid (FA) intake due to food fortification and increased vitamin use. It is reported that diets containing five‐fold higher FA than recommended for mice (5xFASD) during pregnancy resulted in methylenetetrahydrofolate reductase (MTHFR) deficiency and altered choline/methyl metabolism, with neurobehavioral abnormalities in newborns. The goal is to determine whether these changes have their origins in the placenta during embryonic development.

Methods and Results

Female mice are fed control diet or 5xFASD for a month before mating and maintained on these diets until embryonic day 17.5. 5xFASD led to pseudo‐MTHFR deficiency in maternal liver and altered choline/methyl metabolites in maternal plasma (increased methyltetrahydrofolate and decreased betaine). Methylation potential (S‐adenosylmethionine:S‐adenosylhomocysteine ratio) and glycerophosphocholine are decreased in placenta and embryonic liver. Folic acid supplemented diet results in sex‐specific transcriptome profiles in placenta, with validation of dietary expression changes of 29 genes involved in angiogenesis, receptor biology or neurodevelopment, and altered methylation of the serotonin receptor 2A gene.

Conclusion

Moderate increases in folate intake during pregnancy result in placental metabolic and gene expression changes, particularly in angiogenesis, which may contribute to abnormal behavior in pups. These results are relevant for determining a safe upper limit for folate intake during pregnancy.
Recent advancements in corrosion inhibitor systems through carbon allotropes: Past, present, and future
Authors: Verma Chandrabhan , Quraishi M.A. , Ebenso Eno E. , Hussain Chaudhery Mustansar
Published: May 2021

Nano‐sized carbon allotropes, particularly graphene (G), graphene oxide (GO), single and multi‐walled carbon nanotubes (CNTs, SWCNTs, and MWCNTs) and their chemically modified derivatives are widely used in anticorrosive coating formulations. Generally, carbon allotropes acquire nanofiller property and high hydrophobicity which make them ideal anticorrosive materials. Along with various advantages, using carbon allotropes as anticorrosive materials are connected with some specific challenges including un‐controlled dispersion in polymer matrixes. Chemical functionalization using covalent and non‐covalent methods are widely used to enhance their dispersibility. Magnetic stirring, ultrasonic mixing, ball milling and shear emulsification are also widely used to enhance their dispersibility. Present review article describes the covalent and non‐covalent functionalization of G, GO, and CNTs and their application as corrosion inhibitors in various coating formulations and aqueous phase. Chemically modified GO shows remarkable solubility/dispersibility in the aqueous electrolytes. Advantages and challenges using these materials as corrosion inhibitors have also been discussed herein
Unraveling the cause of degradation in Cu(In,Ga)Se2 photovoltaics under potential induced degradation
Authors: Purohit Zeel , Carolus Jorne , Chaliyawala Harsh , Jain Shubhendra K. , Gundimeda Abhiram , Gupta Govind , Tripathi Brijesh , Daenen Michaël
Published: May 2021

Copper indium gallium diselenide (CIGS) based technology is actively competing in the global photovoltaic market with high conversion efficiency. Commercial CIGS modules are anticipated to perform on rated output in the field condition for 20 years. Potential induced degradation (PID) is considered as one of the critical concerns among all the current reliability assessment issues. PID accelerated tests have been performed on pre‐commercial CIGS modules to investigate reduction in electrical performance. We report the severe reduction in electrical performance after PID is correlated to the microstructural and chemical properties of the constituent materials. Under extreme PID stress, the cell surface reveals various defects including crater formation. The aim of this article is to explore the consequences of PID induced craters on the efficiency of CIGS solar cells by investigating material degradation kinetics. In this perspective, we present the root cause of PID in CIGS thin‐film modules in relation to microstructural defects by detailed investigation using J‐V analysis, field emission scanning electron microscope (FESEM), Raman spectroscopy, X‐Ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). This analysis can provide more effective and sustainable research strategies to cultivate more efficient and reliable CIGS technologies in the long run.
Chemical dynamics from the gas‐phase to surfaces
Authors: Auerbach Daniel J. , Tully John C. , Wodtke Alec M.
Published: May 2021

The field of gas‐phase chemical dynamics has developed superb experimental methods to probe the detailed outcome of gas‐phase chemical reactions. These experiments inspired and benchmarked first principles dynamics simulations giving access to an atomic scale picture of the motions that underlie these reactions. This fruitful interplay of experiment and theory is the essence of a dynamical approach perfected on gas‐phase reactions, the culmination of which is a standard model of chemical reactivity involving classical trajectories or quantum wave packets moving on a Born–Oppenheimer potential energy surface. Extending the dynamical approach to chemical reactions at surfaces presents challenges of complexity not found in gas‐phase study as reactive processes often involve multiple steps, such as inelastic molecule‐surface scattering and dissipation, leading to adsorption and subsequent thermal desorption and or bond breaking and making. This paper reviews progress toward understanding the elementary processes involved in surface chemistry using the dynamical approach.

Key points

The fruitful interplay between chemistry and physics leads to an atomic scale view of reactions taking places at catalytically active surfaces.

Improved observations of chemical reactions taking place in complex environments drive the development of new approaches to theoretical chemistry.

Complex reaction networks from real catalysts are boiled down to their elementary steps and examined from first principles.
Polyacrylonitrile/natural loofah sponge with spider web structure as a novel platform for enhanced oil adsorption
Authors: Yang Yuhang , Luo Hao , Yang Huimin , Shi Huiyan , Hou Jiazi
Published: May 2021

Three‐dimensional, inexpensive and environmentally friendly adsorbent materials were urgently in demand for the absorption of organic compounds. In this study, the 3D ultralight sponge was assembled from fragmented electrospun nanofibers of polyacrylonitrile (PAN) and natural loofah. The PAN nanofibers and loofah short fibers were dispersed in an aqueous solution using polyvinyl alcohol (PVA) as the adhesive, and then formed the 3D ultralight sponge by freeze‐drying technology. By adjusting the content of loofah, a kind of spider web structure which was beneficial to enhance oil adsorption was developed arising from polymers dissolution and reconstruction. At the same time, the loofah was integrated with the PAN by ‐OH···N≡C‐ hydrogen bonds to stabilize the structure. Finally, due to the high porosity (99.3%), low density (7.63 kg/m3) and unique spider web structure, our prepared PAN/loofah sponges could absorb organic compounds up to 177 times of their own weight. Hence, the developed PAN/loofah sponge as an environmentally friendly adsorbent would be promising in wastewater treatment.
A structural perspective on targeting the RTK/Ras/MAP kinase pathway in cancer
Authors: Heppner David E. , Eck Michael J.
Published: May 2021

Precision oncology is premised on identifying and drugging proteins and pathways that drive tumorigenesis or are required for survival of tumor cells. Across diverse cancer types, the signaling pathway emanating from receptor tyrosine kinases on the cell surface to RAS and the MAP kinase pathway is the most frequent target of oncogenic mutations, and key proteins in this signaling axis including EGFR, SHP2, RAS, BRAF, and MEK have long been a focus in cancer drug discovery. In this review, we provide an overview of historical and recent efforts to develop inhibitors targeting these nodes with an emphasis on the role that an understanding of protein structure and regulation has played in inhibitor discovery and characterization. Beyond its well‐established role in structure‐based drug design, structural biology has revealed mechanisms of allosteric regulation, distinct effects of activating oncogenic mutations, and other vulnerabilities that have opened new avenues in precision cancer drug discovery.