bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating debris‐flow and anthropogenic disturbance on 10Be concentration in mountain drainage basins: implications for functional connectivity and denudation rates across time scales
Authors: Brardinoni Francesco , Grischott Reto , Kober Florian , Morelli Corrado , Christl Marcus
Published: October 2020

We examine the sensitivity of 10Be concentrations (and derived denudation rates), to debris‐flow and anthropogenic perturbations in steep settings of the Eastern Alps, and explore possible relations with structural geomorphic connectivity. Using cosmogenic 10Be as a tracer for functional geomorphic connectivity, we conduct sampling replications across four seasons in Gadria, Strimm and Allitz Creek. Sampling sites encompass a range of structural connectivity configurations, including the conditioning of a sackung, all assessed through a geomorphometric index (IC). By combining information on contemporary depth of erosion and sediment yield, disturbance history and post‐LGM (Last Glacial Maximum) sedimentation rates, we constrain the effects of debris‐flow disturbance on 10Be concentrations at the Gadria sites. Here, we argue that bedrock weakening imparted by the sackung promotes high depth of erosion. Consequently, debris flows recruit sediment beyond the critical depth of spallogenic production (e.g., >3 m), which in turn, episodically, due to predominantly muogenic production pathways, lowers 10Be concentration by a factor of 4, for at least 2 years. In contrast, steady erosion in Strimm Creek yields very stable 10Be concentrations through time. In Allitz Creek, we observe two‐ to fourfold seasonal fluctuations in 10Be concentrations, which we explain as the combined effects of water diversion and hydraulic structures on sediment mixing. We further show that 10Be concentration correlates inversely with the IC index, where sub‐basins characterized by high concentrations (long residence times) exhibit low IC values (structurally disconnected) and vice versa, implying that, over millennial time scales a direct relation exists between functional and structural connectivity, and that the IC index performed as a suitable metric for structural connectivity. The index performs comparably better than other metrics (i.e., mean slope and mean normalized channel steepness index) previously used to assess topographic controls on denudation rates in active unglaciated ranges. In terms of landscape evolution, we argue that the sackung, by favouring intense debris‐flow activity across the Holocene, has aided rapid postglacial reshaping of the Gadria basin, which currently exhibits a topographic signature characteristic of unglaciated debris‐flow systems. © 2020 John Wiley & Sons, Ltd.
Leveraging Experimental Evaluations for Understanding Causal Mechanisms
Authors: Peck Laura R.
Published: October 2020

Experimental evaluations—especially when grounded in theory‐based impact evaluation—can provide insights into the mechanisms that generate program impacts. This chapter details variants of experimental evaluation designs and also analytic strategies that leverage experimental evaluation data to learn about causal mechanisms. The design variants are poised to illuminate causal mechanisms related to program implementation and the contribution of selected components of multifaceted programs. The analysis strategies lend themselves to illuminating causal mechanisms related to participants’ responses to program components as well as to the contributions of selected program components themselves. The chapter offers an example from one, theory‐based impact evaluation, which embedded both design and analytic strategies to examine the extent to which specific program components and participant experiences might be identified as causal mechanisms. The particular value in using this theory‐based experimental strategy is that the results are rigorous and potentially highly relevant to policy and practice.
Unpacking Mechanisms in Climate Resilient Agriculture Interventions
Authors: Barrett Sam , D'Errico Stefano , Anderson Simon , Nebsu Bayu
Published: October 2020

The investigation of causal mechanisms has the capacity to provide donors and implementing institutions with a greater understanding of people's reasoning and reactions as they work with interventions. This chapter contributes to the literature by identifying behavioral mechanisms generated through engagement with climate‐resilient agriculture interventions within a larger livelihood project in Ethiopia. It works through the steps that enabled the study to unpack the black box between the climate‐smart interventions and the outcome of crop production. The first step was a matching‐based sampling design, following households over 3 years with six biannual surveys, and setting up a quasi‐experimental evaluation setting. The second step used the data generated from the surveys in difference‐in‐difference models to assess the impact of the intervention on crop production. Third, to gain insight into the mechanisms at work, Focus Group Discussions (FGD) were conducted with smallholder farmer project beneficiaries. The FGDs revealed what the beneficiaries themselves considered the key mechanisms generated from the intervention, thus forming the bridge between the interventions and outcome. The result was an evaluation design enabling deeper insight into attribution claims. The findings offered novel insights for policymakers about how the climate‐resilient interventions worked for the people themselves and shedding light on the inner workings of the climate‐smart technologies. Finally, they provided key stakeholders (commissioning agency and implementing organizations) with a powerful means by which to learn about the last project, so to better plan for the next iteration and improve the climate resilience of smallholder farmers.
Aroma absorption in rapeseed oil using rotating packed bed
Authors: Lukin Ilya , Pietzka Lukas , Wingartz Isabell , Schembecker Gerhard
Published: October 2020

An increasing consumers’ call for natural aromas fuels the development of biotechnological aroma production. Although aroma fermentation is quite advantageous, especially severe product losses of volatile compounds through the bioreactor off‐gas may challenge the downstream processing. The application of novel process intensification methods to overcome the common drawbacks of conventional apparatuses might be helpful on a way to commercial competitiveness of biotechnological aromas. This study explored the suitability of rotating packed bed (RPB), a rotating mass transfer enhancing machine, for the absorption of model aroma compounds in rapeseed oil. Increasing the rotation speed from 500 to 2750 rpm led to two‐ to threefold higher absorption efficiencies at elsewise constant conditions. Aiming for an enriched aromatic intermediate, 2.5 L of rapeseed oil was processed in a recycle for 200 minutes, and a final concentration of benzaldehyde of 0.323 ± 0.026 g/Loil was achieved. Compared to packed columns, the RPB outperforms at equal packing depth or requires less packing area to deliver same efficiency. Especially, the use of custom 3D‐printed spiral packing with elaborated wall film flow combined with rotation supported liquid distribution allows using absorbents with viscosities as high as 100 mPa·s at low pressure drop increase. However, small dimensions severely limit the performance of a laboratory‐scale RPB as the casing contributes disproportionally to mass transfer.
Solid‐State Alkaline Fuel Cell Performance of Pentablock Terpolymer with Methylpyrrolidinium Cations as Anion Exchange Membrane and Ionomer
Authors: Hwang M. , Sun R. , Willis C. , Elabd Y. A.
Published: October 2020

In this study, pentablock terpolymers with methylpyrrolidinium cations were characterized and investigated as anion exchange membranes and ionomers for solid‐state alkaline fuel cells. The pentablock terpolymer (with methylpyrrolidinium cations) membranes exhibited higher fuel cell power density and durability than commercial FuMA‐Tech (with quaternary ammonium cations) membranes at 30 °C, 100% relative humidity (RH). Optimization of the catalyst ink composition (i.e., solids and solvent ratio) and fuel cell performance of membrane electrode assemblies (MEAs) with pentablock terpolymers as both the membrane and ionomer were also investigated. Optimization of the fuel cell operating conditions corroborates with the in situ electrochemical impedance spectroscopy results. The pentablock terpolymer MEA exhibited a maximum power density of 83.3 mW cm−2 and voltage decay rate of 0.7 mV h−1 after 100 h of operation under 40 °C, 100% RH. These results show promise for pentablock terptolymers with methylpyrrolidinium cations as a commercially attractive low‐cost alternative anion exchange membrane and ionomer for solid‐state alkaline fuel cells.
Computing and visualising intra‐voxel orientation‐specific relaxation–diffusion features in the human brain
Authors: de Almeida Martins João P. , Tax Chantal M. W. , Reymbaut Alexis , Szczepankiewicz Filip , Chamberland Maxime , Jones Derek K. , Topgaard Daniel
Published: October 2020

Diffusion MRI techniques are used widely to study the characteristics of the human brain connectome in vivo. However, to resolve and characterise white matter (WM) fibres in heterogeneous MRI voxels remains a challenging problem typically approached with signal models that rely on prior information and constraints. We have recently introduced a 5D relaxation–diffusion correlation framework wherein multidimensional diffusion encoding strategies are used to acquire data at multiple echo‐times to increase the amount of information encoded into the signal and ease the constraints needed for signal inversion. Nonparametric Monte Carlo inversion of the resulting datasets yields 5D relaxation–diffusion distributions where contributions from different sub‐voxel tissue environments are separated with minimal assumptions on their microscopic properties. Here, we build on the 5D correlation approach to derive fibre‐specific metrics that can be mapped throughout the imaged brain volume. Distribution components ascribed to fibrous tissues are resolved, and subsequently mapped to a dense mesh of overlapping orientation bins to define a smooth orientation distribution function (ODF). Moreover, relaxation and diffusion measures are correlated to each independent ODF coordinate, thereby allowing the estimation of orientation‐specific relaxation rates and diffusivities. The proposed method is tested on a healthy volunteer, where the estimated ODFs were observed to capture major WM tracts, resolve fibre crossings, and, more importantly, inform on the relaxation and diffusion features along with distinct fibre bundles. If combined with fibre‐tracking algorithms, the methodology presented in this work has potential for increasing the depth of characterisation of microstructural properties along individual WM pathways.
Recurrent amplification of grid‐cell activity
Authors: D'Albis Tiziano , Kempter Richard
Published: October 2020

High‐level cognitive abilities such as navigation and spatial memory are thought to rely on the activity of grid cells in the medial entorhinal cortex (MEC), which encode the animal's position in space with periodic triangular patterns. Yet the neural mechanisms that underlie grid‐cell activity are still unknown. Recent in vitro and in vivo experiments indicate that grid cells are embedded in highly structured recurrent networks. But how could recurrent connectivity become structured during development? And what is the functional role of these connections? With mathematical modeling and simulations, we show that recurrent circuits in the MEC could emerge under the supervision of weakly grid‐tuned feedforward inputs. We demonstrate that a learned excitatory connectivity could amplify grid patterns when the feedforward sensory inputs are available and sustain attractor states when the sensory cues are lost. Finally, we propose a Fourier‐based measure to quantify the spatial periodicity of grid patterns: the grid‐tuning index.
Governance disclosure quality and market valuation of firms in UK and Germany
Authors: Ullah Subhan , Ahmad Sardar , Akbar Saeed , Kodwani Devendra , Frecknall‐Hughes Jane
Published: October 2020

This study develops a “comply or explain” index which captures compliance and quality of explanations given for non‐compliance with the corporate governance codes in UK and Germany. In particular, we explain, how compliance and quality of explanations provided in non‐compliance disclosures, and various other internal corporate governance mechanisms, affect the market valuation of firms in the two countries. A dynamic generalised method of moments (GMM) estimator is employed as the research technique for our analysis, which enabled us to control for the potential effects of endogeneity in our models. The findings of our content analysis suggest that firms exhibit significant differences in compliance, board independence and ownership structure in both countries. The “comply or explain” index is positively associated with the market valuation of UK firms suggesting that compliance and quality governance disclosure are value relevant in the UK. Institutional blockholders' ownership is, however, negatively associated with the market value of firms, which raises questions about the monitoring role of institutional shareholders in both countries. We argue that both compliance and explanations given for non‐compliance are equally important, as long as valid reasons and justifications for non‐compliance are provided by the reporting companies. These findings thus imply that the “comply or explain” principle is working well and that UK and German companies could benefit from the flexibility offered by this principle. With respect to the role of board size, board independence, ownership structure, and institutional ownership of firms, this study offers policy implications.
The SARS‐CoV‐2 pandemic scenario in Africa: What should be done to address the needs of pregnant women?
Authors: Charles Charles M’poca , Amoah Emefa Modey , Kourouma Kadidiatou Raissa , Bahamondes Luis Guilhermo , Cecatti José Guilherme , Osman Nafissa Bique , Govule Philip , Diallo Abdou Karim , Sacarlal Jahit , Pacagnella Rodolfo de Carvalho
Published: October 2020

Synopsis

The need for prospective monitoring of COVID‐19 cases among pregnant women, and coordinated information‐sharing to inform pragmatic responses to the pandemic in the context of LMICs, is greater now than ever.
Prognostic factors associated with cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy in recurrent ovarian cancer
Authors: Ayhan Ali , Akilli Huseyin
Published: October 2020

Objective

To identify factors affecting survival for women undergoing cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (HIPEC).

Methods

A retrospective study at Baskent University School of Medicine, Ankara, Turkey. Data were evaluated for 71 women with recurrent ovarian cancer who underwent cytoreductive surgery with R0 resection plus HIPEC between 2016 and 2019. Potential factors affecting survival (platinum sensitivity, bevacizumab administration before HIPEC, albumin and CA125 levels, presence of ascites, age, number of chemotherapy lines, and time interval between last chemotherapy and HIPEC) were evaluated. Complications of HIPEC were documented.

Results

The median age was 58 years, and the median follow‐up was 12 months. In univariate analyses, platinum sensitivity, albumin level, and time since last chemotherapy cycle affected overall survival. In multivariate Cox regression analysis, use of bevacizumab before HIPEC (hazard ratio [HR], 6.7; 95% confidence interval [CI], 1.39–32.3; P=0.018) and presence of ascites (HR, 5.3; 95% CI, 1.65–17.5; P=0.005) were independent negative prognostic factors. Seven (8.9%) women experienced grade III–IV complications.

Conclusion

In recurrent ovarian cancer, HIPEC is a promising treatment with mild‐to‐moderate toxicity. However, the presence of ascites and progression under bevacizumab treatment before HIPEC seem to be negative prognostic factors; these findings will be important for patient selection.
My Life the Way I See It: Reconstructing Minoritized Youth With Disabilities as Critical Thinkers
Authors: Leu Grace Shih-en
Published: October 2020

The author looked closely at students’ artifacts as a way to consider how students with disabilities engage in critical literacy to develop critical consciousness of their worlds and re‐create positive identities of themselves. Findings include how high school minoritized students with disabilities create counternarratives that reject dominant narratives of their identities as underachievers and academically deficient. Students’ work revealed their critical consciousness of problems within policing and urban schooling and reconstructed themselves as academically successful, persistent in overcoming difficulties, and hopeful of a positive future. Significance for educators includes the possibilities of teaching students with disabilities using a general education curriculum.
The performance of 3D bioscaffolding based on a human periodontal ligament stem cell printing technique
Authors: Tian Yinping , Liu Minyi , Liu Yaoyao , Shi Changzheng , Wang Yayu , Liu Tong , Huang Yi , Zhong Peihua , Dai Jian , Liu Xiangning
Published: October 2020

Bone tissue plays an important role in supporting and protecting the structure and function of the human body. Bone defects are a common source of injury and there are many reconstruction challenges in clinical practice. However, 3D bioprinting of scaffolds provides a promising solution. Hydrogels have emerged as biomaterials with good biocompatibility and are now widely used as cell‐loaded materials for bioprinting. This study involved three steps: First, sodium alginate (SA), gelatin (Gel), and nano‐hydroxyapatite (na‐HA) were mixed into a hydrogel and its rheological properties assessed to identify the optimum slurry for printing. Second, SA/Gel/na‐HA bioscaffolds were printed using 3D bioprinting technology and their physical properties characterized for surface morphology, swelling, and mechanical properties. Finally, human periodontal ligament stem cells (hPDLSCs) were mixed with SA/Gel/na‐HA printing slurry to create a “bioink” to prepare SA/Gel/na‐HA/ hPDLSCs cell bioscaffolds. These were tested for biocompatibility and osteogenic differentiation performance using live/dead cell staining, cell adhesion, cell proliferation, and alkaline phosphatase activity. The SA/Gel/na‐HA hydrogel exhibited shear‐thinning behavior. The equilibrium swelling of the bioscaffold was 125.9%, the compression stress was 0.671 MPa, and the compression elastic modulus was 8.27 MPa. The SA/Gel/na‐HA/hPDLSCs cell bioscaffolds caused effective stimulation of cell survival, proliferation, and osteoblast differentiation. Therefore, the SA/Gel/na‐HA/hPDLSCs cell bioscaffolds displayed potential as a material for bone defect reconstruction.
Autophagy displays divergent roles during intermittent amino acid starvation and toxic stress‐induced senescence in cultured skeletal muscle cells
Authors: Bloemberg Darin , Quadrilatero Joe
Published: October 2020

Due to the ever‐expanding functions attributed to autophagy, there is widespread interest in understanding its contribution to human physiology; however, its specific cellular role as a stress‐response mechanism is still poorly defined. To investigate autophagy's role in this regard, we repeatedly subjected cultured mouse myoblasts to two stresses with diverse impacts on autophagic flux: amino acid and serum withdrawal (Hank's balanced salt solution [HBSS]), which robustly induces autophagy, or low‐level toxic stress (staurosporine, STS). We found that intermittent STS (int‐STS) administration caused cell cycle arrest, development of enlarged and misshapen cells/nuclei, increased senescence‐associated heterochromatic foci and senescence‐associated β‐galactosidase activity, and prevented myogenic differentiation. These features were not observed in cells intermittently incubated in HBSS (int‐HB). While int‐STS cells displayed less DNA damage (phosphorylated H2A histone family, member X content) and caspase activity when administered cisplatin, int‐HB cells were protected from STS‐induced cell death. Interestingly, STS‐induced senescence was attenuated in autophagy related 7‐deficient cells. Therefore, while repeated nutrient withdrawal did not cause senescence, autophagy was required for senescence caused by toxic stress. These results illustrate the context‐dependent effects of different stressors, potentially highlighting autophagy as a distinguishing factor.
Combination of ethanol and Fe3O4@C‐SO3H pretreatment of Eucalyptus for glucose release via enzymatic saccharification
Authors: Luo Jia , Qian Le , Zhu Yu‐Qin , Zhang Fan , Jiang Li‐Qun
Published: October 2020

BACKGROUND

Enzymatic hydrolysis of lignocellulose is regarded as the most efficient route to producing fermentable sugars, one kind of promising future biofuel, while physiochemical pretreatment is the initial but most critical step for the efficient utilization of lignocellulose.

RESULTS

In this study, a recoverable carbonaceous solid acid catalyst Fe3O4@C‐SO3H was used in combined organosolv pretreatment of Eucalyptus biomass at 140–180 °C with 50 vol% ethanol. The introduction of solid acid in ethanol pretreatment remarkably alleviated the requirement of smaller biomass size, but provided less influence on cellulosic degradation, which benefited the subsequent enzymatic hydrolysis to glucose. After the pretreatment using 50 vol% ethanol and 20% catalyst at 160 °C, 60.3% hemicellulose and 52.6% lignin were removed from Eucalyptus (75–250 μm) within 60 min, which resulted in a cellulose retention ratio of >90% and improved hydrolysis efficiency by nearly 20 and 2 folds, respectively, compared to untreated and ethanol pretreated materials.

CONCLUSION

This study explored a novel pretreatment technique to improve the efficiency of enzymatic saccharification. It also demonstrated that the hydrolysis yield of cellulose had significantly positive correlation with the removal of lignin and hemicellulose in Eucalyptus, but was less affected by cellulose crystallinity. © 2020 Society of Chemical Industry
Monocyte subsets predict mortality after cardiac arrest
Authors: Krychtiuk Konstantin A , Lenz Max , Richter Bernhard , Hohensinner Philipp J , Kastl Stefan P , Mangold Andreas , Huber Kurt , Hengstenberg Christian , Wojta Johann , Heinz Gottfried , Speidl Walter S
Published: October 2020

After successful cardiopulmonary resuscitation (CPR), many patients show signs of an overactive immune activation. Monocytes are a heterogeneous cell population that can be distinguished into 3 subsets by flow cytometry (classical monocytes [CM: CD14++CD16-], intermediate monocytes [IM: CD14++CD16+CCR2+] and non-classical monocytes [NCM: CD14+CD16++CCR2-]). Fifty-three patients admitted to the medical intensive care unit (ICU) after cardiac arrest were included. Blood was taken on admission and after 72 h. The primary endpoint of this study was survival at 6 months and the secondary endpoint was neurological outcome as determined by cerebral performance category (CPC)-score at 6 months. Median age was 64.5 (49.8-74.3) years and 75.5% were male. Six-month mortality was 50.9% and survival with good neurological outcome was 37.7%. Monocyte subset distribution upon admission to the ICU did not differ according to survival. Seventy-two hours after admission, patients who died within 6 months showed a higher percentage of the pro-inflammatory subset of IM (8.3% [3.8-14.6]% vs. 4.1% [1.5–8.2]%; P = 0.025), and a lower percentage of CM (87.5% [79.9–89.0]% vs. 90.8% [85.9–92.7]%; P = 0.036) as compared to survivors. In addition, IM were predictive of outcome independent of time to ROSC and witnessed cardiac arrest, and correlated with CPC-score at 6 months (R = 0.32; P = 0.043). These findings suggest a possible role of the innate immune system in the pathophysiology of post cardiac arrest syndrome.
Is serum biotinidase enzyme activity a potential marker of perturbed glucose and lipid metabolism?
Authors: Forny Patrick , Burda Patricie , Bode Peter , Rohrbach Marianne
Published: October 2020

Glycogen storage diseases (GSDs) belong to the group of inborn errors of carbohydrate metabolism. Hepatic GSDs predominantly involve the liver and most present with hepatomegaly. Biochemically they show known disturbances in glucose and fatty acids metabolism, namely fasting hypoglycaemia and increased triglycerides. Additionally, increased biotinidase (BTD) enzyme activity has been shown to be associated with many GSD types, whereas the mechanism by which BTD enzyme activity is altered remains unknown so far. We aimed to delineate changes in gluconeogenesis and fatty acid synthesis, potentially explaining raised BTD enzyme activity, by using liver (specimens from 2 patients) and serum samples of GSD Ia and GSD IV patients. By expression analysis of genes involved in gluconeogenesis, we ascertained increased levels of phosphoenolpyruvate carboxykinase and fructose‐1,6‐biphosphatase, indicating an increased flux through the gluconeogenic pathway. Additionally, we found increased gene expression of the biotin‐dependent pyruvate and acetyl‐CoA carboxylases, providing substrate for gluconeogenesis and increased fatty acid synthesis. We also observed a significant linear correlation between BTD enzyme activity and triglyceride levels in a cohort of GSD Ia patients. The results of this pilot study suggest that enhancement of BTD activity might serve the purpose of providing extra cofactor to the carboxylase enzymes as an adjustment to disturbed glucose and fatty acid metabolism. Future studies involving a higher number of samples should aim at confirming the here proposed mechanism, which extends the application of BTD enzyme activity measurement beyond its diagnostic purpose in suspected GSD, and opens up possibilities for its use as a sensor for increased gluconeogenesis and fatty acid synthesis.
Employing molecularly imprinted polymers in the development of electroanalytical methodologies for antibiotic determination
Authors: Benachio Ingrid , Lobato Alnilan , Gonçalves Luís Moreira
Published: October 2020

Antibiotics, although being amazing compounds, need to be monitored in the environment and foodstuff. This is primarily to prevent the development of antibiotic resistance that may make them ineffective. Unsurprisingly, advances in analyticalsciences that can improve their determination are appreciated. Electrochemical techniques are known for their simplicity, sensitivity, portability and low‐cost; however, they are often not selective enough without recurring to a discriminating element like an antibody. Molecular imprinting technology aims to create artificial tissues mimicking antibodies named molecularly imprinted polymers (MIPs), these retain the advantages of selectivity but without the typical disadvantages of biological material, like limited shelf‐life and high cost. This manuscript aims to review all analytical methodologies for antibiotics, using MIPs, where the detection technique is electrochemical, like differential pulse voltammetry (DPV), square‐wave voltammetry (SWV) or electrochemical impedance spectroscopy (EIS). MIPs developed by electropolymerization (e‐MIPs) were applied in about 60 publications and patents found in the bibliographic search, while MIPs developed by other polymerization techniques, like temperature assisted (“bulk”) or photopolymerization, were limited to around 40. Published works covered the electroanalysis of a wide range of different antibiotics (β‐lactams, tetracyclines, quinolones, macrolides, aminoglycosides, among other), in a wide range of matrices (food, environmental and biological).
Features of the upper tropospheric cyclonic vortices of Northeast Brazil in life cycle stages
Authors: de Morais Michelyne Duarte Coutinho , Gan Manoel Alonso , Yoshida Marcos Cezar
Published: October 2020

The main purpose of the study is to explore in more detail the Upper Tropospheric Cyclonic Vortices (UTCVs) features over Northeast Brazil (NEB) in an attempt to improve weather forecasts. The various aspects of the life cycle features of the UTCVs over NEB are presented here, because these aspects have not been investigated in previous studies. Initially, the UTCVs were identified at 200 hPa, and then, they were identified at lower levels to analyse their vertical structure, using 6‐hr data for a 30‐year period (1984–2013) from the European Center for Medium Range Weather Forecasts' reanalysis (ERA Interim). An objective method was improved to obtain at first‐hand the trajectory and the vertical extent of the UTCVs over NEB. Some statistics results were consistent with previous studies related to relative frequency, duration and direction of movement. However, further results were obtained too. An average distance of 2,000 km for the UTCVs total travel was found. Of this average distance, 750 km was reached by UTCVs on the first day of the life cycle, leading to the presumption of a possible suppression of vortex movement that depends on a diabatic mechanism. We also found predominance of UTCVs without vertical tilt or with east tilt with increasing height. When considering life cycle stages (formation, maximum depth and dissipation), diversity was observed in intensity with stages, levels and seasons of the year, with spring exhibiting the most intense UTCVs over all seasons. Finally, our finding about interannual variability is novel. There was a tendency for the average number of UTCVs to be slightly higher during El Niño summers compared with La Niña summers.
Changes in temperature extremes and their relationship with ENSO in Malaysia from 1985 to 2018
Authors: Tan Mou Leong , Juneng Liew , Tangang Fredolin T. , Chung Jing Xiang , Radin Firdaus R. B.
Published: October 2020

Understanding the changes in temperature extremes is important for managing and coping with the risks associated with regional climate change. However, the climatological characteristics of temperature extremes and their variabilities is still not adequately studies in Malaysia. This study evaluates the spatial and temporal variations of temperature extremes over Malaysia for the period 1985–2018. This study includes four phases: (a) collection, quality control and homogeneity analysis of temperature data; (b) general (TXmean, TNmean, TMmean and DTR), warm (TXx, TNx, TX90p and TN90p) and cool (TXn, TNn, TX10p and TN10p) temperature extreme indices calculations; (c) trend analysis of temperature extremes using the Mann‐Kendall and Sens's slope test; and (d) analyses of correlations between temperature extremes and El Niño‐Southern Oscillation (ENSO). The results indicate a warming of surface temperature across Malaysia, particularly in Peninsular Malaysia. In general, TXmean, TNmean and TMmean increased significantly at 5% significance level by 0.12°C/decade, 0.27°C/decade and 0.17°C/decade, respectively. A significant decreasing trend in DTR by 0.12°C/decade is seen, which is related to the higher increasing rate of TNmean. All of the warm extreme indices, TXx, TNx, TX90p and TN90p presents significant increasing trends by 0.19°C/decade, 0.28°C/decade, 2.86%/decade and 3.08%/decade, respectively. For the cool extreme indices, TX10p and TN10p decreased significantly by 0.95%/decade and 3.18%/decade, respectively, though the trend in TXn by 0.11°C/decade is not statistically significant. The only cool index presenting a significant increasing trend is TNn by 0.44°C/decade, indicating a reduction of cool nights. Besides that, major cities in the northern and western parts of Peninsular Malaysia generally exhibit a higher warming trend compared to rural and highland area. These are possibly related to the intensified urban heat island effect under the rapid urbanization. This study also found that the ENSO affected warm extreme indices much stronger than cool extreme indices in Malaysia.
Chemical composition and health benefits of coconut oil: an overview
Authors: Deen Afka , Visvanathan Rizliya , Wickramarachchi Dhanushki , Marikkar Nazrim , Nammi Sirinivas , Jayawardana Barana C , Liyanage Ruvini
Published: October 2020

Coconut oil is an integral part of Sri Lankan and many South Asian diets. Initially, coconut oil was classified along with saturated fatty acid food items and criticized for its negative impact on health. However, research studies have shown that coconut oil is a rich source of medium‐chain fatty acids. Thus, this has opened new prospects for its use in many fields. Beyond its usage in cooking, coconut oil has attracted attention due to its hypocholesterolemic, anticancer, antihepatosteatotic, antidiabetic, antioxidant, anti‐inflammatory, antimicrobial and skin moisturizing properties. Despite all the health benefits, consumption of coconut oil is still underrated due to a lack of supportive scientific evidence. Even though studies done in Asian countries claim a favorable impact on cardiac health and serum lipid profile, the limitations in the number of studies conducted among Western countries impede the endorsement of the real value of coconut oil. Hence, long‐term extensive studies with proper methodologies are suggested to clear all the controversies and misconceptions of coconut oil consumption. This review discusses the composition and functional properties of coconut oils extracted using various processing methods. © 2020 Society of Chemical Industry
Isomer‐dependent reaction mechanisms of cyclic ether intermediates: cis‐2,3‐dimethyloxirane and trans‐2,3‐dimethyloxirane
Authors: Doner Anna C. , Davis Matthew M. , Koritzke Alanna L. , Christianson Matthew G. , Turney Justin M. , Schaefer Henry F. , Sheps Leonid , Osborn David L. , Taatjes Craig A. , Rotavera Brandon
Published: October 2020

Oxiranes are a class of cyclic ethers formed in abundance during low‐temperature combustion of hydrocarbons and biofuels, either via chain‐propagating steps that occur from unimolecular decomposition of β‐hydroperoxyalkyl radicals (β‐̇QOOH) or from reactions of HȮO with alkenes. The cis‐ and trans‐isomers of 2,3‐dimethyloxirane are intermediates of n‐butane oxidation, and while rate coefficients for β‐̇QOOH → 2,3‐dimethyloxirane + ̇OH are reported extensively, subsequent reaction mechanisms of the cyclic ethers are not. As a result, chemical kinetics mechanisms commonly adopt simplified chemistry to describe the consumption of 2,3‐dimethyloxirane by convoluting several elementary reactions into a single step, which may introduce mechanism truncation error—uncertainty derived from missing or incomplete chemistry.

The present research examines the isomer dependence of 2,3‐dimethyloxirane reaction mechanisms in support of ongoing efforts to minimize mechanism truncation error. Reaction mechanisms are inferred via the detection of products from Cl‐initiated oxidation of both cis‐2,3‐dimethyloxirane and trans‐2,3‐dimethyloxirane using multiplexed photoionization mass spectrometry (MPIMS). The experiments were conducted at 10 Torr and temperatures of 650 K and 800 K. To complement the experiments, the enthalpies of stationary points on the ̇R + O2 surfaces were computed at the ccCA‐PS3 level of theory. In total, 28 barrier heights were computed on the 2,3‐dimethyloxiranylperoxy surfaces. Two notable aspects are low‐lying pathways that form resonance‐stabilized ketohydroperoxide‐type radicals caused by ̇QOOH ring‐opening when the unpaired electron is localized adjacent to the ether group, and cis‐trans isomerization of ̇R and ̇QOOH radicals, via inversion, which enable reaction pathways otherwise restricted by stereochemistry.

Several species were identified in the MPIMS experiments from ring opening of 2,3‐dimethyloxiranyl radicals. Neither of the two conjugate alkene isomers prototypical of ̇R + O2 reactions were detected. Products were also identified from decomposition of ketohydroperoxide‐type radicals. The present work provides the first analysis of 2,3‐dimethyloxirane oxidation chemistry and reveals that consumption pathways are complex and require the expansion of submechanisms in chemical kinetics mechanisms.
LncRNA H19 inhibits high glucose‐induced inflammatory responses of human retinal epithelial cells by targeting miR‐19b to increase SIRT1 expression
Authors: Luo Rong , Li Lan , Hu Yu‐Xiang , Xiao Fan
Published: October 2020

Diabetic retinopathy (DR) is a common complication of diabetes mellitus. Inflammatory responses play crucial roles in the progress of DR. Long noncoding RNA (lncRNAs) and microRNAs (miRNAs) are key signal transduction molecules in retina, and tightly connected with DR occurrence and development. Our study aimed to explore the functions of lncRNA H19, miR‐19b and silence information regulator factor related enzymes 1 (SIRT1) in the progress of DR. Retinal pigment epithelial cells (ARPE‐19) were used to build high‐glucose (HG) model. Quantitative real‐time PCR (qPCR) was performed to detect expression of H19, miR‐19b and SIRT1 at normal glucose (NG) and HG conditions. And western blotting was performed to test protein level of SIRT1. QPCR and enzyme‐linked immunosorbent assay were performed to detect expression of inflammatory cytokines. Finally, the interactions among H19, miR‐19b and SIRT1 were determined by dual‐luciferase reporter assay. Our results showed that lncRNA H19 and SIRT1 were reduced, while miR‐19b was increased in ARPE‐19 cells with HG condition. MiR‐19b positively regulated the expression of inflammatory cytokines, including TNF‐α, IL‐1β and IL‐6. Inhibition of miR‐19b and overexpression of H19 inhibited the expression of inflammatory cytokines, such as TNF‐α, IL‐1β and IL‐6, while knockdown of SIRT1 reversed their effects on inflammatory cytokines. Furthermore, overexpression of miR‐19b reversed the inhibitory effects of overexpression of H19 on inflammatory cytokines. Importantly, H19 targeted miR‐19b to downregulate miR‐19b expression. Furthermore, miR‐19b bound to SIRT1 and declined SIRT1 expression. H19/miR‐19b/SIRT1 axis plays a key role of HG‐induced inflammatory response in ARPE‐19 cells, which provides new targets for DR treatment.
Biocompatible Crosslinked Nanofibers of Poly(Vinyl Alcohol)/Carboxymethyl‐Kappa‐Carrageenan Produced by a Green Process
Authors: Madruga Liszt Y. C. , Balaban Rosangela C. , Popat Ketul C. , Kipper Matt J.
Published: October 2020

This study presents a new type of biocompatible nanofiber based on poly(vinyl alcohol) (PVA) and carboxymethyl‐kappa‐carrageenan (CMKC) blends, produced with no generation of hazardous waste. The nanofibers are produced by electrospinning using PVA:CMKC blends with ratios of 1:0, 1:0.25, 1:0.4, 1:0.5, and 1:0.75 (w/w PVA:CMKC) in aqueous solution, followed by thermal crosslinking. The diameter of the fibers is in the nanometer scale and below 300 nm. Fourier transform infrared spectroscopy shows the presence of the carboxyl and sulfate groups in all the fibers with CMKC. The nanofibers from water‐soluble polymers are stabilized by thermal crosslinking. The incorporation of CMKC improves cytocompatibility, biodegradability, cell growth, and cell adhesion, compared to PVA nanofibers. Furthermore, the incorporation of CMKC modulates phenotype of human adipose‐derived stem cells (ADSCs). PVA/CMKC nanofibers enhance ADSC response to osteogenic differentiation signals and are therefore good candidates for application in tissue engineering to support stem cells.
Assessment of Ataxia Rating Scales and Cerebellar Functional Tests: Critique and Recommendations
Authors: Perez‐Lloret Santiago , van de Warrenburg Bart , Rossi Malco , Rodríguez‐Blázquez Carmen , Zesiewicz Theresa , Saute Jonas A.M. , Durr Alexandra , Nishizawa Masatoyo , Martinez‐Martin Pablo , Stebbins Glenn T. , Schrag Anette , Skorvanek Matej ,   and members of the MDS Rating Scales Review Committee
Published: October 2020

Background

We assessed the clinimetric properties of ataxia rating scales and functional tests, and made recommendations regarding their use.

Methods

A systematic literature search was conducted to identify the instruments used to rate ataxia symptoms. The identified rating scales and functional ability tests were reviewed and ranked by the panel as “recommended,” “suggested,” or “listed” for the assessment of patients with discrete cerebellar disorders, using previously established criteria.

Results

We reviewed 14 instruments (9 rating scales and 5 functional tests). “Recommended” rating scales for the assessment of symptoms severity were: for Friedreich's ataxia, the Friedreich's Ataxia Rating Scale, the International Cooperative Ataxia Rating Scale (ICARS), and the Scale for the Assessment and Rating of Ataxia (SARA); for spinocerebellar ataxias, ICARS and SARA; for ataxia telangiectasia: ICARS and SARA; for brain tumors, SARA; for congenital disorder of glycosylation‐phosphomannomutase‐2 deficiency, ICARS; for cerebellar symptoms in multiple sclerosis, ICARS; for cerebellar symptoms in multiple system atrophy: Unified Multiple System Atrophy Rating Scale and ICARS; and for fragile X–associated tremor ataxia syndrome, ICARS. “Recommended” functional tests were: for Friedreich's ataxia, Ataxia Functional Composite Score and Composite Cerebellar Functional Severity Score; and for spinocerebellar ataxias, Ataxia Functional Composite Score, Composite Cerebellar Functional Severity Score, and SCA Functional Index.

Conclusions

We identified some “recommended” scales and functional tests for the assessment of patients with major hereditary ataxias and other cerebellar disorders. The main limitations of these instruments include the limited assessment of patients in the more severe end of the spectrum and children. Further research in these populations is warranted. © 2020 International Parkinson and Movement Disorder Society
Physiotherapists' experiences of managing persons with suspected cauda equina syndrome: Overcoming the challenges
Authors: Paling Claire , Hebron Clair
Published: October 2020

Introduction

Cauda equina syndrome (CES) is rare, but its symptoms are not and musculoskeletal physiotherapists frequently encounter persons with suspected CES. Given that delayed diagnosis of CES can result in devastating consequences for affected persons and costly litigation for healthcare organisations, it is imperative that persons presenting with suspected CES are well managed. However, this may present a challenge to physiotherapists. Therefore, the aim of this study is to explore physiotherapists' experiences of managing persons with suspected CES.

Methods

Semi‐structured interviews were conducted with musculoskeletal physiotherapists. Verbatim transcripts were analysed using an interpretive paradigm and thematic analysis.

Ethical approval

Ethical approval was obtained from a university Ethics committee and NHS Research and Development.

Findings

Five interlinking themes emerged. The themes of worry in relation to risk management and communication difficulties seemed to represent significant challenges. The remaining themes were described as antidotes to these challenges: Lightening the load with teamwork and shared responsibility, the usefulness of a clear pathway and perception of improved confidence and competence with experience and training.

Discussion

The findings are discussed in the context of other literature, and practical recommendations are made relating to pathway implementation, team working, communication aids, training on CES and measures to care for staff wellbeing.

Conclusion

Findings suggest that it is important to be aware of and address the challenges faced by physiotherapists in order to care for clinicians' wellbeing and ensure a safe and smooth journey for persons with suspected CES.

Summary Video: https://www.youtube.com/watch?v=lIHqCKIQ1jk&t=90s
Thermo‐hydro‐mechanical modeling of fracturing porous media with two‐phase fluid flow using X‐FEM technique
Authors: Khoei A. R. , Mortazavi S. M. S.
Published: October 2020

In this paper, a fully coupled thermo‐hydro‐mechanical model is presented for two‐phase fluid flow and heat transfer in fractured/fracturing porous media using the extended finite element method. In the fractured porous medium, the traction, heat, and mass transfer between the fracture space and the surrounding media are coupled. The wetting and nonwetting fluid phases are water and gas, which are assumed to be immiscible, and no phase‐change is considered. The system of coupled equations consists of the linear momentum balance of solid phase, wetting and nonwetting fluid continuities, and thermal energy conservation. The main variables used to solve the system of equations are solid phase displacement, wetting fluid pressure, capillary pressure, and temperature. The fracture is assumed to impose the strong discontinuity in the displacement field and weak discontinuities in the fluid pressure, capillary pressure, and temperature fields. The mode I fracture propagation is employed using a cohesive fracture model. Finally, several numerical examples are solved to illustrate the capability of the proposed computational algorithm. It is shown that the effect of thermal expansion on the effective stress can influence the rate of fracture propagation and the injection pressure in hydraulic fracturing process. Moreover, the effect of thermal loading is investigated properly on fracture opening and fluids flow in unsaturated porous media, and the convective heat transfer within the fracture is captured successfully. It is shown how the proposed computational model is capable of modeling the fully coupled thermal fracture propagation in unsaturated porous media.
A stochastic programming approach for chemotherapy appointment scheduling
Authors: Demir Nur Banu , Gul Serhat , Çelik Melih
Published: October 2020

Chemotherapy appointment scheduling is a challenging problem due to the uncertainty in premedication and infusion durations. In this paper, we formulate a two‐stage stochastic mixed integer programming model for the chemotherapy appointment scheduling problem under limited availability of nurses and infusion chairs. The objective is to minimize the expected weighted sum of nurse overtime, chair idle time, and patient waiting time. The computational burden to solve real‐life instances of this problem to optimality is significantly high, even in the deterministic case. To overcome this burden, we incorporate valid bounds and symmetry breaking constraints. Progressive hedging algorithm is implemented in order to solve the improved formulation heuristically. We enhance the algorithm through a penalty update method, cycle detection and variable fixing mechanisms, and a linear approximation of the objective function. Using numerical experiments based on real data from a major oncology hospital, we compare our solution approach with several scheduling heuristics from the relevant literature, generate managerial insights related to the impact of the number of nurses and chairs on appointment schedules, and estimate the value of stochastic solution to assess the significance of considering uncertainty.
Socioeconomic impact of breast cancer on young women in Ghana: A qualitative study
Authors: Iddrisu Merri , Aziato Lydia , Ohene Lillian A.
Published: October 2020

Aim

This study was undertaken to discover the socioeconomic impact of breast cancer on young women in Ghana.

Methods

A qualitative exploratory and descriptive design was used to recruit 12 young women from the University of Ghana hospital, 37 Military hospital and Ridge hospital. Individual interviews were conducted face to face and data transcribed verbatim and analysed using content analysis.

Results

Three themes emerged: perceptions and beliefs; economic concerns; and secrecy. Participants perceived that breast cancer was a test of faith, a spiritual disease that is contagious and disgraceful. Mostly, participants stopped work to cater for themselves, and as a result, they encountered financial challenges. Their challenges were compounded with conscious efforts to keep diagnosis secret to avoid being stigmatized.

Conclusion

Young women living with breast cancer need support physically, economically and socially from healthcare providers, their families and the society at large.