bluuebunny/crossref_metadata_2025 huggingface dataset:
The variation in the levels of 18 amino acids in the cortex and plasma of cerebral ischemia C57BL/6 mice
Authors: Li Jian‐Sha , Qiu Hong‐mei , Jiang Qing‐song , Liu Yong‐hong , Zhang Jing , Gong Tao , Jiang Xin‐hui
Published: February 2021

Emerging evidence suggests that amino acid (AA) neurotransmitters play important roles in the pathophysiological processes of cerebral ischemia. In this work, an HPLC with fluorescence detection (HPLC‐FLR) method was developed for the simultaneous determination of 18 AAs in the cortex and plasma after cerebral ischemia in mice. The ischemia model was prepared by bilateral common carotid artery occlusion, and then the cortex and plasma of the sham, ischemia, and naringenin groups were collected. Based on the protein precipitation method, a simple and effective sample preparation method was developed. The treated sample contained minimal proteins and lipids. The analysis of the sample was performed by the proposed HPLC‐FLR method in combination witho‐phthalaldehyde. The results showed a statistically significant increase in excitatory AAs (aspartic acid and glutamic acid), inhibitory AAs (glycine and 4‐aminobutyric acid), phenylalanine, citrulline, isoleucine, and leucine levels, and a decrease of glutathione and phenylalanine levels when compared with the sham group in the cortex. Besides, the administration of naringenin had significant effects on excitatory AAs, inhibitory AA (glycine), glutamine, tyrosine, phenylalanine, and leucine levels when compared with the sham group in the cortex. These findings could be utilized in studying and clarifying the mechanisms of ischemia.
Accentuating the interconnection between business sustainability and organizational performance in the context of the circular economy: The moderating role of organizational competitiveness
Authors: Sarfraz Muddassar , Ivascu Larisa , Belu Radian , Artene Alin
Published: February 2021

Sustainability development has gained significant importance in the modern business environment. The primary objective is to conduct an explanatory and quantitative study of the impacts of the social, economic, and environmental dimensions on organizational performance, considering the moderating role of organizational competitiveness. Data were collected from Chinese, Italian, and Romanian small and medium enterprises (SMEs). The questionnaires were distributed by applying simple random sampling techniques. The study sample size consists of 320 SME employees. Hierarchical regression was used to investigate the moderating impacts of organizational competitiveness on the relationships of the social, economic, and environmental dimensions and organizational performance. The regression analysis shows a positive relationship between the study variables. Small and medium‐sized enterprises are focusing more on sustainable business practices.
Larotrectinib in a NTRK‐rearranged soft tissue sarcoma in the neoadjuvant setting: A case report
Authors: Percy Catherine , Schubert Thomas , Galant Christine , Kirchgesner Thomas , Mazzeo Filomena
Published: February 2021

Patients with soft tissue sarcomas should be assessed for neurotrophic tropomyosin receptor kinase (NTRK) gene fusions as neoadjuvant treatment with larotrectinib may prevent amputation.
Investigation of Bubble Behavior in Gas‐Solid Fluidized Beds with Different Gas Distributors
Authors: Jang Kwangbyol , Feng Yali , Li Haoran
Published: February 2021

The behavior of gas bubbles in a gas‐solid fluidized bed was investigated by computational fluid dynamics simulation. A two‐phase flow model incorporating the kinetic theory of granular flow was used to study the effect of gas distributor design on the size distribution and the rise velocity of gas bubbles in the bed column. The experiments were conducted on four gas distributors with different orifice sizes and pitches. The geometry of the gas distributor had a significant influence on the bubble behavior in the gas‐solid fluidized bed. The effects of static bed height and superficial gas velocity were also considered. Bubble diameter and bubble rise velocity increased with gas velocity. However, at low bed height, the deviation in bubble size was indistinct because at higher gas velocity the rising tendency of the bubble formed just above the gas distributor increased and the probability of bubble coalescence decreased.
Peptization Control of Composite Materials Containing Water Glass for Spray Drying of Catalysts
Authors: Saavedra Andres Carrasco , Seifert Markus , Hannß Mariella , Henle Thomas , Lê-Anh Mai , Busse Oliver , Weigand Jan J.
Published: February 2021

Silica‐based composite particles are complex catalyst materials that are widely used in petrochemistry. The preparation of particles that are well defined in form, composition, and chemical and rheological behavior by spray drying of suspensions remains an important industrial challenge. Here, zeolite HY, kaolin, and the cheap binder water glass are used. Experimental and model regimes of slurry peptization are analyzed based on their pH value, zeta potential, and mixing speed to control the process. The results show a pseudoplastic behavior of the silica slurries for zeta potential below 20 mV, which is explained by surface charge, hydroxyls, and pH‐dependent coagulation. Thus, a quick acidification of the slurry, additional mechanic shear, and subsequent pH control during spray drying enable control of peptization kinetics.
Study of Heat and Mass Transfer by Bionic Fractal Microchannel Plates
Authors: Niu Yating , Huang Pingnan , Pan Minqiang
Published: February 2021

Bionic fractal microchannel plates are becoming popular because of their low pressure drop and high heat‐transfer efficiency. But there is still no systematic research on the heat and mass transfer mechanism of bionic fractal microchannel plates, which has limited their widespread use. A mathematical model of heat and mass transfer in bionic fractal microchannel plates is developed and the influences of their structural parameters on heat and mass transfer are evaluated. The results provide a systematic knowledge of bionic fractal microchannel plates which may help to guide their optimization for practical applications.
Ionomer Thin‐Films by Electrochemical Synthesis: Bipolar and Ampholytic Membranes
Authors: Pasquini Luca , Di Vona Maria Luisa , Sgreccia Emanuela , Ruzimuradov Olim , Knauth Philippe
Published: February 2021

Thin‐films of cation‐conducting poly(styrene sulfonate) (PSS) and anion‐conducting poly(N‐vinyl‐N‐benzyl‐N,N,N‐trimethylammonium chloride) (PVBTMA) were electrochemically deposited. A low film thickness can be obtained, because the electrodeposition is a self‐limiting process. Various cases were explored: i) the deposition of a single ionomer layer on various substrates, ii) the sequential deposition of the ionomers giving a bipolar membrane, and iii) the co‐deposition of the ionomers giving an ampholytic membrane. The structure and microstructure of the thin films were investigated by NMR spectroscopy and optical and scanning electron microscopy (SEM). Impedance spectroscopy in through‐plane configuration revealed a large resistance of the bipolar membrane, due to the ionic blocking interface between the ionomers. The ampholytic membrane also showed a low conductivity, probably due to the loss of ionic carrier pairs that can leave the ionomer without break of electroneutrality.
(Fe,Ni)9S8 Nanosheets on a Three‐Dimensional Conductive Substrate for Efficient Oxygen Evolution Reaction Electrocatalysis
Authors: Shi Bu‐Yan , Huang Yuan , Jiang Li‐Wen , Chowdhury Mahabubur , Liu Hong , Wang Jian‐Jun
Published: February 2021

The development of low‐cost and high‐efficiency electrocatalysts for the oxygen evolution reaction (OER) is essential for a number of applications in the field of energy conversion and storage. Herein, we present an efficient OER electrocatalyst in the form of thin (Fe,Ni)9S8 nanosheets (FNS NSs) anchored on a three‐dimensional (3D) conductive substrate of Fe/Fe3O4 nanoislands/carbon cloth (Fe NIs/CC). The resulting electrode exhibits an impressive OER performance with a low overpotential of 147 mV at 10 mA cm−2 and a Tafel slope of 29.8 mV dec−1 in 1 M KOH alkaline solution. The enhanced performance is ascribed to the thin nanosheet structure with ample active sites, the high conductivity of the substrate, and the 3D structure, which endow the electrode with a large specific surface area and more catalytic active sites. Study of the kinetic process reveals that the incorporation of Fe from the substrate can reduce the kinetic barrier of OER, allowing for a faster reaction rate.
Mathematical modelling of hydrothermal performance for Kenics type static mixer using power law obeying fluids
Authors: Mukherjee Joydeb , Pandit Aniruddha B.
Published: February 2021

In this study, analytical, numerical, and experimental works are presented to demonstrate hydrothermal characteristics of a flow choosing non‐Newtonian behaviour through a Kenics type static mixer. Experiments are conducted by varying the superficial fluid velocities of the heterogeneous mixture oil with Sudan dye and water, as well as for the homogeneous aqueous system, consisting of CMC (2 wt%) in water. Six static mixing elements are placed in series, and the corresponding wall temperatures of the inline pipe are varied over a range of 293–363 K. In the context of hydrodynamic study, analytical models are solved using the Bessel function and Laguerre function and validated with the in‐house experimental results and numerical results. In the thermal performance study, mathematical models are formulated based on differential transformation method (DTM) and homotopy perturbation method (HPM), and have been validated with the numerical results. The deviation among the experimentally measured average pressure drops estimated from our experiment and that predicted by analytical models is found to be as low as ±8.1%. The deviation between the analytical results obtained from the HPM and DTM method and numerical results based on the finite volume method solution of the same equation is observed as low as ±4%. Additionally, both proposed analytical methods used are compared with each other to evaluate the dimensionless swirl flow velocity and temperature gradient of the inline Kenics Static mixer. In the thermal performance study, we observe that the DTM is in good agreement with the numerical method as compared to HPM.
Recent Progress in Extending the Cycle‐Life of Secondary Zn‐Air Batteries
Authors: Prakoso Bagas , Mahbub Muhammad Adib Abdillah , Yilmaz Meltem , Khoiruddin  , Wenten I. Gede , Handoko Albertus Denny , Sumboja Afriyanti
Published: February 2021

Secondary Zn‐air batteries with stable voltage and long cycle‐life are of immediate interest to meet global energy storage needs at various scales. Although primary Zn‐air batteries have been widely used since the early 1930s, large‐scale development of electrically rechargeable variants has not been fully realized due to their short cycle‐life. In this work, we review some of the most recent and effective strategies to extend the cycle‐life of Zn‐air batteries. Firstly, diverse degradation routes in Zn‐air batteries will be discussed, linking commonly observed failure modes with the possible mechanisms and root causes. Next, we evaluate the most recent and effective strategies aimed at tackling individual or multiple of these degradation routes. Both aspects of cell architecture design and materials engineering of the electrodes and the electrolytes will be thoroughly covered. Finally, we offer our perspective on how the cycle‐life of Zn‐air batteries can be extended with concerted and tailored research directions to pave the way for their use as the most promising secondary battery system of the future.
Optimizing bitmap index encoding for high performance queries
Authors: Yildiz Beytullah
Published: February 2021

Many sources such as historical archives, sensor readings, health systems, and machine records produce ever‐increasing but often unchanging data. These accumulating data create a need for faster processing. Bitmap index, which can take advantage of multi‐core and multiprocessor systems, is designed to process data that increase over time but do not change frequently. It has a well‐known advantage, especially in queries on data with low cardinality. However, bitmap index can handle high cardinality data efficiently because it can use its own compression algorithm. Bitmap index has many encoding schemes that affect query processing time. In this study, we developed an algorithm that improves query performance by using optimal encoding among bitmap encodings. With this optimization algorithm, we witnessed up to 40% performance increase in queries made with bitmap indexes created with different encodings. Furthermore, in comparison with a commonly used relational database, we found significant improvements in the number of query operations per second performed on optimized encoded bitmap indexes generated by the introduced algorithm.
Graphitic Carbon Nitride (g‐C3N4) Nanosheets as a Multipurpose Material for Detection of Amines and Solar‐Driven Hydrogen Production
Authors: Vu Manh Hiep , Nguyen Chinh Chien , Do Trong‐On
Published: February 2021

Graphitic carbon nitride nanosheets decorated by multiple functional groups (denoted as CN−KNa) were as a multipurpose material, both in photocatalytic applications and as a photo‐induced indicator. The presented g‐C3N4 is fabricated via a facile alkali‐salt‐assisted calcination method. The structural analysis reveals significant changes in the structure of the host CN−KNa nanosheets associated with the existence of multiple functional groups (for example, hydroxy, carbonyl, and cyano groups). Such modifications lead to enhanced light absorption and charge separation, resulting in an efficient photocatalyst not only for solar‐driven hydrogen production but also for primary amine detection in aqueous solution. Thus, the solar light driven photocatalytic hydrogen evolution yield using the synthesized CN−KNa sample is found to be 50.3 μmol h−1, which is approximately 14 times higher than that of bulk g‐C3N4. More importantly, this functional‐group‐decorated CN−KNa facilitated electron transportation between CN−KNa and amine compounds, causing a colour change in the solution mixture, which has been observed for the first time. This novel observation indicates that CN−KNa can be considered a new class of photo‐induced indicator agent to detect primary amine compounds in aqueous solution.
The higher they climb, the harder they fall: The role of self‐brand connectedness in consumer responses to corporate social responsibility hypocrisy
Authors: Baghi Ilaria , Antonetti Paolo
Published: February 2021

Past research shows how information about corporate irresponsibility that contradicts an organization's social responsibility commitments causes hypocrisy perceptions. Extant research on stakeholder engagement however, has not explained how inconsistent corporate social responsibility (CSR) information affects the perceptions of consumers strongly connected with a brand. This study investigates how, rather than protecting the firm against hypocrisy perceptions, self‐brand connectedness magnifies the negative effect of inconsistent CSR information. We tested the research hypotheses across two experimental studies, using both fictitious and real brands in two different industries. We estimated a multi‐group structural equation model model to show how self‐brand connectedness increases people's willingness to distance themselves from the hypocritical brand. Results show that consumers that feel close to the hypocritical brand have a stronger desire to disengage their identity from the brand and protect their self‐esteem. The desire to avoid the brand in turn drives more negative consumer reactions in terms of brand attitudes, brand loyalty and negative word of mouth. Our findings contribute to the literature by demonstrating that a close relationship between the consumer and the brand may aggravate behavioral reactions to hypocrisy perceptions. This is the first study to consider how hypocrisy perceptions influence attitude and behaviors of consumers that are closely connected to the company. Our results extend research on hypocrisy perceptions and brand avoidance by showing that closely connected consumers are especially likely to reject brands that send inconsistent messages about their involvement in CSR.
Pericardial metastasis from alveolar rhabdomyosarcoma: A case report
Authors: Straccia Patrizia , Martini Maurizio , Pierconti Francesco
Published: February 2021

Alveolar rhabdomyosarcoma (ARMS) commonly occurring in children and adolescents, is a rare and aggressive soft tissue malignancy demonstrating rapid growth and dissemination. Although their histopathologic and immunohistochemical findings are well known, cytomorphological features on serous effusions have not been well documented. A case of metastatic rhabdomyosarcoma diagnosed on cytological examination of the pericardial fluid cytology and discuss the diagnostic difficulties that were encountered in this case has been presented.
A comparative study between outcomes of an in‐person versus online introductory field course
Authors: Race Alexandra I. , De Jesus Maria , Beltran Roxanne S. , Zavaleta Erika S.
Published: February 2021

The COVID‐19 pandemic has disrupted many standard approaches to STEM education. Particularly impacted were field courses, which rely on specific natural spaces often accessed through shared vehicles. As in‐person field courses have been found to be particularly impactful for undergraduate student success in the sciences, we aimed to compare and understand what factors may have been lost or gained during the conversion of an introductory field course to an online format. Using a mixed methods approach comparing data from online and in‐person field‐course offerings, we found that while community building was lost in the online format, online participants reported increased self‐efficacy in research and observation skills and connection to their local space. The online field course additionally provided positive mental health breaks for students who described the time outside as a much‐needed respite. We maintain that through intentional design, online field courses can provide participants with similar outcomes to in‐person field courses.
Developing hierarchical density‐structured models to study the national‐scale dynamics of an arable weed
Authors: Goodsell Robert M. , Childs Dylan Z. , Spencer Matthew , Coutts Shaun , Vergnon Remi , Swinfield Tom , Queenborough Simon A. , Freckleton Robert P.
Published: February 2021

Population dynamics can be highly variable in the face of environmental heterogeneity, and understanding this variation is central in the study of ecology. Robust management decisions require that we understand how populations respond to management at a range of scales, and under a broad suite of conditions. Population models are potentially valuable tools in addressing this challenge. However, without adequate data, models can fail to produce useful results. Populations of arable weeds are particularly problematic in this respect, as they are widespread and their dynamics are extremely variable. Owing to the inherent cost of collecting data, most studies of plant population dynamics are derived from localized experiments under a small range of environmental conditions, limiting the extent to which variance in population dynamics can be measured. Density‐structured models provide a route to rapid, large‐scale analysis of population dynamics, and can expand the scale of ecological models that are directly tied to data. Here we extend previous density‐structured models to include environmental heterogeneity, variation in management, and to account for inter‐population variation. We develop, parameterize, and test hierarchical density‐structured models for a common agricultural weed, black‐grass (Alopecurus myosuroides). We model the dynamics of this species in response to crop management, using survey data gathered over 4  yr from 364 fields across a network of 45 UK farms. We show that hierarchical density‐structured models provide a substantial improvement over their nonhierarchical counterparts. Using these models, we demonstrate that several alternative crop rotations are effective in reducing weed densities. Rotations with high wheat prevalence exhibit the most severe infestations, and diverse rotations generally have lower weed densities. However, a key outcome is that in many cases the effect of crop rotation is small compared to the high variability arising from spatiotemporal heterogeneity. This result highlights the need to monitor and model population dynamics across large spatial and temporal scales in order to account for variation in the drivers of plant dynamics. Our framework for data collection and modeling provides a means to achieve this.
Unusually large upward shifts in cold‐adapted, montane mammals as temperature warms
Authors: McCain Christy M. , King Sarah R. B. , Szewczyk Tim M.
Published: February 2021

The largest and tallest mountain range in the contiguous United States, the Southern Rocky Mountains, has warmed considerably in the past several decades due to anthropogenic climate change. Herein we examine how 47 mammal elevational ranges (27 rodent and 4 shrew species) have changed from their historical distributions (1886–1979) to their contemporary distributions (post 2005) along 2,400‐m elevational gradients in the Front Range and San Juan Mountains of Colorado. Historical elevational ranges were based on more than 4,580 georeferenced museum specimen and publication records. Contemporary elevational ranges were based on 7,444 records from systematic sampling efforts and museum specimen records. We constructed Bayesian models to estimate the probability a species was present, but undetected, due to undersampling at each 50‐m elevational bin for each time period and mountain range. These models leveraged individual‐level detection probabilities, the number and patchiness of detections across 50‐m bands of elevation, and a decaying likelihood of presence from last known detections. We compared 95% likelihood elevational ranges between historical and contemporary time periods to detect directional change. Responses were variable as 26 mammal ranges changed upward, 6 did not change, 11 changed downward, and 4 were extirpated locally. The average range shift was 131 m upward, while exclusively montane species shifted upward more often (75%) and displayed larger average range shifts (346 m). The best predictors of upper limit and total directional change were species with higher maximum latitude in their geographic range, montane affiliation, and the study mountain was at the southern edge of their geographic range. Thus, mammals in the Southern Rocky Mountains serve as harbingers of more changes to come, particularly for montane, cold‐adapted species in the southern portion of their ranges.
Renal and intraglomerular haemodynamics in chronic heart failure with preserved and reduced ejection fraction
Authors: Jung Susanne , Bosch Agnes , Kolwelter Julie , Striepe Kristina , Kannenkeril Dennis , Schuster Tizia , Ott Christian , Achenbach Stephan , Schmieder Roland E.
Published: February 2021

Aims

Congestive heart failure (CHF) and impaired renal function are two often co‐existing medical conditions and associated with adverse cardiovascular outcome. The aim of the current study was to assess renal and intraglomerular haemodynamics by constant infusion input clearance technique in subjects with CHF.

Methods and results

The group of subjects with CHF consisted of 27 individuals with HFpEF and 27 individuals with HFrEF and were compared with 31 healthy controls. Subjects underwent renal clearance examination to measure glomerular filtration rate (GFR) and renal blood and plasma flow (RBF and RPF) and to calculate intraglomerular haemodynamics such as resistances of the afferent (RA) and efferent arterioles (RE) as well as intraglomerular pressure (Pglom). Measured GFR was lower in CHF subjects (68.1 ± 10.1 mL/min/1.73 m2) compared with controls (83.6 ± 13.4 mL/min/1.73 m2, Padj < 0.001) as was Pglom (Padj < 0.001). Total renal vascular resistance (RVR) was higher in CHF subjects (87.3 ± 20.1 vs. 73.8 ± 17.1 dyn × s/cm5, Padj < 0.001) mediated by an increased resistance at the afferent site (3201 ± 1084 vs. 2181 ± 796 dyn × s/cm5, Padj < 0.001). Comparing HFpEF and HFrEF subjects, RA was higher in HFrEF subjects. The severity of CHF assessed by NT‐proBNP revealed an inverse association with renal perfusion (RPF r = −0.421, P = 0.002, RBF r = −0.414, P = 0.002) and a positive relation with RVR (r = 0.346, P = 0.012) at the post‐glomerular site (RE: r = 0.318, P = 0.022).

Conclusions

Renal function assessed by measured GFR is reduced and renal vascular resistance at the preglomerular, afferent site is increased in HFpEF and, to greater extent, in HFrEF. Our data indicate a close cardiorenal interaction in CHF.
Improved Single‐Site Chromium Catalysts with Electron Rich Indenyl Ligands for the Formation of Ultrahigh Molecular Weight Polyethylene
Authors: Hansen Helge‐Boj , Wadepohl Hubert , Enders Markus
Published: February 2021

Quinolyl functionalized indenyl chromium complexes with different substitution patterns were synthesized and evaluated as single site catalysts in ethylene polymerization. Adding substituents like a fused cyclohexyl ring or a Si(CH3)3 group to the indenyl moiety improve complex stability, solubility and catalytic activity compared to the unsubstituted analogues. Furthermore, the ability to incorporate 1‐hexene into the polymer chain increased. Ultrahigh molecular weight polyethylene (UHMW‐PE) or linear low density polyethylene (LLD‐PE) with very high molecular weight was obtained. Although other catalysts are able to incorporate more 1‐hexene only a few systems are known, that combine substantial 1‐hexene incorporation with very high activity and such high molecular weights. Consequently, these catalytic systems are attractive candidates in industrial processes for the production of improved polyethylene materials.
The Role of Chain Length in Cucurbit[8]uril Complexation of Methyl Alkyl Viologens
Authors: Pedrini Alessandro , Devi Das Anjali , Pinalli Roberta , Hickey Neal , Geremia Silvano , Dalcanale Enrico
Published: February 2021

Viologens are among the most studied guests for cucurbit[8]uril (CB[8]) and their complexation is usually driven by bipyridyl core inclusion inside the cavity to maximize both hydrophobic and cation‐dipole interactions. The presence of alkyl substituents on the guest alters this complexation mode, switching to aliphatic chain inclusion in U‐folded conformation. Herein, we report a thorough study of the influence of the alkyl chain length on the binding mode of methyl alkyl viologens. The chain length of the studied guests was increased by two methylene groups starting from methyl dodecyl viologen (MVC12) to the octadecyl analogue (MVC18). Complexation in water, investigated by NMR spectroscopy and ITC, revealed a clear switch from 1 : 1 to 2 : 1 host/guest stoichiometry moving from 12 to 16 carbon atoms, as a consequence of the chain folding of the major portion of the longer alkyl chain in one CB[8] cavity and the inclusion of the full viologen unit by another host molecule. The CB[8]2.MVC18 complex crystal structure evidences the unprecedented 2 : 1 stoichiometry and quantified in 12 the number of carbon atoms necessary to fill the CB[8] cavity in U‐shaped conformation.
Expression and secretion of apoE isoforms in astrocytes and microglia during inflammation
Authors: Lanfranco Maria Fe , Sepulveda Jordy , Kopetsky Gregory , Rebeck G. William
Published: February 2021

Neuroinflammation is a common feature in neurodegenerative diseases, modulated by the Alzheimer's disease risk factor, apolipoprotein E (APOE). In the brain, apoE protein is synthesized by astrocytes and microglia. We examined primary cultures of astrocytes and microglia from human APOE (E2, E3, and E4) targeted‐replacement mice. Astrocytes secreted two species of apoE, whereas cellular apoE consisted of only one. Both forms of secreted astrocytic apoE were bound during glycoprotein isolation, and enzymatic removal of glycans produced a convergence of the two forms of apoE to a single form; thus, the two species of astrocyte‐secreted apoE are differentially glycosylated. Microglia released only a single species of apoE, while cellular apoE consisted of two forms; the secreted apoE and one of the two forms of cellular apoE were glycosylated. We treated the primary glia with either endogenous (TNFα) or exogenous (LPS) pro‐inflammatory stimuli. While LPS had no effect on astrocytic apoE, APOE2, and APOE3 microglia increased release of apoE; APOE4 microglia showed no effect. APOE4 microglia showed higher baseline secretion of TNFα compared to APOE2 and APOE3 microglia. TNFα treatment reduced the secretion and cellular expression of apoE only in APOE4 astrocytes. The patterns of apoE species produced by astrocytes and microglia were not affected by inflammation. No changes in APOE mRNA were observed in astrocytes after both treatments. Together, our data demonstrate that astrocytes and microglia differentially express and secrete glycosylated forms of apoE and that APOE4 astrocytes and microglia are deficient in immunomodulation compared to APOE2 and APOE3.
Delirium in older adults is associated with development of new dementia: a systematic review and meta‐analysis
Authors: Pereira Jarett Vanz‐Brian , Aung Thein May Zin , Nitchingham Anita , Caplan Gideon A.
Published: February 2021

Objectives

Observational studies have examined the association between delirium and development of new dementia. However, no recent review has collectively assessed the available evidence quantitatively and qualitatively. We systematically reviewed and critically evaluated the literature regarding the association between delirium and dementia, and calculated the odds of developing new dementia after having delirium.

Methods

This systematic review and meta‐analysis was conducted according to Preferred reporting items for systematic reviews and meta‐analyses guidelines. MEDLINE, EMBASE and PsycINFO, were searched for English‐language articles that compared the incidence of new dementia in older adult (≥65) inpatients with delirium, to inpatients without delirium. A random effects model was used for meta‐analysis, and overall effect size was calculated using reported raw data of event counts. The Newcastle‐Ottawa Quality Assessment scale assessed risk of bias.

Results

Six observational studies met eligibility criteria, with follow‐up times ranging from six months to five years. Four looked at hip fracture surgical patients; one was on cardiac surgery patients and one examined geriatric medical patients. All studies excluded patients with pre‐existing dementia. Pooled meta‐analysis revealed that older adult inpatients who developed delirium had almost twelve times the odds of subsequently developing new dementia compared to non‐delirious patients (OR = 11.9 [95% CI: 7.29–19.6]; p < 0.001).

Conclusions

Older adult inpatients who develop delirium are at significant risk of subsequently developing dementia. This emphasises the importance of delirium prevention and cognitive monitoring post‐delirium. The included studies mainly examined post‐surgical patients—further research on medical and intensive care unit cohorts is warranted. Future studies should assess whether delirium duration, severity and subtype influence the risk of developing dementia.
Chemical functionalization of 2D black phosphorus
Authors: Liu Yajuan , Chen Muqing , Yang Shangfeng
Published: February 2021

As an emerging two‐dimensional material, black phosphorus (BP) has fascinating structure and electronic properties, affording broad applications in field‐effect transistors, optoelectronic devices, energy devices, and biomedicines. However, the lone pair electrons of phosphorus atoms readily react with oxygen, so few‐layer BP is easily oxidized and degraded when exposed to air. Therefore, the ambient stability of BP needs to be enhanced for its potential application. Chemical functionalization is one of the most effective methods for improving the ambient stability of few‐layer BP. In this review, we provide a comprehensive overview of the chemical functionalization of BP, focusing on covalent and noncovalent functionalization and surface coordination. The influence of the functionalization pattern on the electronic properties and ambient stability of BP is summarized. Finally, the challenges and future development of chemical functionalization of BP are discussed.

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A Bisphosphonate With a Low Hydroxyapatite Binding Affinity Prevents Bone Loss in Mice After Ovariectomy and Reverses Rapidly With Treatment Cessation
Authors: Coffman Abigail A , Basta‐Pljakic Jelena , Guerra Rosa M , Ebetino Frank H , Lundy Mark W , Majeska Robert J , Schaffler Mitchell B
Published: February 2021

Bisphosphonates (BPs) are a mainstay of osteoporosis treatment; however, concerns about bone health based on oversuppression of remodeling remain. Long‐term bone remodeling suppression adversely affects bone material properties with microdamage accumulation and reduced fracture toughness in animals and increases in matrix mineralization and atypical femur fractures in patients. Although a “drug holiday” from BPs to restore remodeling and improve bone quality seems reasonable, clinical BPs have long functional half‐lives because of their high hydroxyapatite (HAP) binding affinities. This places a practical limit on the reversibility and effectiveness of a drug holiday. BPs with low HAP affinity and strong osteoclast inhibition potentially offer an alternative approach; their antiresorptive effect should reverse rapidly when dosing is discontinued. This study tested this concept using NE‐58025, a BP with low HAP affinity and moderate osteoclast inhibition potential. Young adult female C57Bl/6 mice were ovariectomized (OVX) and treated with NE‐58025, risedronate, or PBS vehicle for 3 months to test effectiveness in preventing long‐term bone loss. Bone microarchitecture, histomorphometry, and whole‐bone mechanical properties were assessed. To test reversibility, OVX mice were similarly treated for 3 months, treatment was stopped, and bone was assessed up to 3 months post‐treatment. NE‐58025 and RIS inhibited long‐term OVX‐induced bone loss, but NE‐58025 antiresorptive effects were more pronounced. Withdrawing NE‐58025 treatment led to the rapid onset of trabecular resorption with a 200% increase in osteoclast surface and bone loss within 1 month. Cessation of risedronate treatment did not lead to increases in resorption indices or bone loss. These results show that NE‐58025 prevents OVX‐induced bone loss, and its effects reverse quickly following cessation treatment in vivo. Low‐HAP affinity BPs may have use as reversible, antiresorptive agents with a rapid on/off profile, which may be useful for maintaining bone health with long‐term BP treatment. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Bone Geometry Is Altered by Follistatin‐Induced Muscle Growth in Young Adult Male Mice
Authors: Chan Audrey S M , McGregor Narelle E , Poulton Ingrid J , Hardee Justin P , Cho Ellie H‐J , Martin T John , Gregorevic Paul , Sims Natalie A , Lynch Gordon S
Published: February 2021

The development of the musculoskeletal system and its maintenance depends on the reciprocal relationship between muscle and bone. The size of skeletal muscles and the forces generated during muscle contraction are potent sources of mechanical stress on the developing skeleton, and they shape bone structure during growth. This is particularly evident in hypermuscular global myostatin (Mstn)‐null mice, where larger muscles during development increase bone mass and alter bone shape. However, whether muscle hypertrophy can similarly influence the shape of bones after the embryonic and prepubertal period is unknown. To address this issue, bone structure was assessed after inducing muscle hypertrophy in the lower hindlimbs of young‐adult C57BL/6J male mice by administering intramuscular injections of recombinant adeno‐associated viral vectors expressing follistatin (FST), a potent antagonist of Mstn. Two FST isoforms were used: the full‐length 315 amino acid isoform (FST‐315) and a truncated 288 amino acid isoform (FST‐288). In both FST‐treated cohorts, muscle hypertrophy was observed, and the anterior crest of the tibia, adjacent to the tibialis anterior muscle, was lengthened. Hypertrophy of the muscles surrounding the tibia caused the adjacent cortical shell to recede inward toward the central axis: an event driven by bone resorption adjacent to the hypertrophic muscle. The findings reveal that inducing muscle hypertrophy in mice can confer changes in bone shape in early adulthood. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
The oncogenic and tumor suppressive roles of RNA‐binding proteins in human cancers
Authors: Bitaraf Amirreza , Razmara Ehsan , Bakhshinejad Babak , Yousefi Hassan , Vatanmakanian Mousa , Garshasbi Masoud , Cho William C. , Babashah Sadegh
Published: February 2021

Posttranscriptional regulation is a mechanism for the cells to control gene regulation at the RNA level. In this process, RNA‐binding proteins (RBPs) play central roles and orchestrate the function of RNA molecules in multiple steps. Accumulating evidence has shown that the aberrant regulation of RBPs makes  contributions to the initiation and progression of tumorigenesis via numerous mechanisms such as genetic changes, epigenetic alterations, and noncoding RNA‐mediated regulations. In this article, we review the effects caused by RBPs and their functional diversity in the malignant transformation of cancer cells that occurs through the involvement of these proteins in various stages of RNA regulation including alternative splicing, stability, polyadenylation, localization, and translation. Besides this, we review the various interactions between RBPs and other crucial posttranscriptional regulators such as microRNAs and long noncoding RNAs in the pathogenesis of cancer. Finally, we discuss the potential approaches for targeting RBPs in human cancers.
Dapagliflozin ameliorates pancreatic injury and activates kidney autophagy by modulating the AMPK/mTOR signaling pathway in obese rats
Authors: Jaikumkao Krit , Promsan Sasivimon , Thongnak Laongdao , Swe Myat T. , Tapanya Monruedee , Htun Khin T. , Kothan Suchart , Intachai Nuttawadee , Lungkaphin Anusorn
Published: February 2021

Chronic consumption of a high‐fat diet induces obesity and impairs the ultra‐structure of organs and tissues. We examined the effect of sodium‐glucose cotransporter 2 (SGLT2) inhibitor‐dapagliflozin on renal and pancreatic injuries in obese condition. Rats were fed a high‐fat diet for 16 weeks to induce obesity. After that, dapagliflozin or vildagliptin, 1.0 or 3.0 mg/kg/day, respectively, was administered by oral gavage for 4 weeks. The effects of dapagliflozin on insulin resistance, kidney autophagy, pancreatic oxidative stress, endoplasmic reticulum (ER) stress, inflammation, and apoptosis in high‐fat diet‐induced obese rats were elucidated. High‐fat‐diet fed rats demonstrated metabolic abnormalities including increased body weight, visceral fat weight, plasma insulin, plasma cholesterol, homeostasis model assessment (HOMA) index, and TAUCg, indicating the obese‐insulin resistant and glucose intolerance conditions. Also, high‐fat‐diet fed rats exhibited significant pancreatic injury accompanied by decreased kidney autophagy. Dapagliflozin or vildagliptin treatment for 4 weeks ameliorated pancreatic oxidative stress, ER stress, inflammation, and apoptosis and restored kidney autophagy in obese rats. Moreover, the morphology changes of the pancreas and kidney were improved in the treated groups. Interestingly, dapagliflozin showed higher efficacy than vildagliptin in improving body weight, visceral fat weight, plasma cholesterol level, and pancreatic oxidative stress in our model. Taken together, the present study demonstrated that the therapeutic effects of dapagliflozin attenuated pancreatic injury, pancreatic oxidative stress, ER stress, inflammation, apoptosis, and exerted renoprotective effects by restoring autophagic signaling in obese rats.
Elucidation of the dimeric interplay of dual MRAP2 proteins in the zebrafish
Authors: Wang Meng , Zhai Yue , Lu Liumei , Zhang Cong , Li Na , Xue Song , Cheng Daofu , Fu Shaliu , Liu Qi , Zhang Chao
Published: February 2021

The melanocortin receptor accessory protein 2 (MRAP2) plays an essential role in the regulation of metabolic homeostasis and deletion of which results in severe obesity syndrome in mice and human. Mammalian MRAP2 is recognized as an endogenous physiological mediator through the potentiation of the MC4R signaling in vivo. Two isoforms of MRAP2 are identified in zebrafish genome, zMRAP2a and zMRAP2b. However, the mechanism of assembling dual topology and the regulatory roles of each complex on the melanocortin cascades remains unclear. In this study, we showed the bidirectional homo‐ and hetero‐dimeric topologies of two zebrafish MRAP2 isoforms on the plasma membrane. Orientation fixed chimeric proteins could affect the trafficking and pharmacological properties of zMC4R signaling. Reciprocal replacement of zMRAP2a and zMRAP2b proteins elucidated the major participation of the carboxyl terminal as the functional domain for modulating zMC4R signaling. Our findings revealed the complex and dynamic conformational regulation of dual zebrafish MRAP2 proteins in vitro.
Assessing the pipeline: Perceived barriers to applying to dental school among pipeline program alumni
Authors: Burns Lorel E. , Pezzullo Cheryline , Amable Rose J. , Mayorga Lenny , Mejia Eugenia E.
Published: February 2021

Purpose/Objectives

The aim of this study was to increase the understanding of perceived barriers to applying to dental school experienced by underrepresented minority (URM), pipeline program alumni.

Methods

A qualitative study of alumni of New York University College of Dentistry pipeline programs, aimed at increasing the number of URM and low‐income students in the dental profession, was conducted in 2020. Focus groups were convened to examine perceived barriers to applying to dental school and identified through a combination inductive and deductive thematic analysis.

Results

Twenty‐three pipeline program alumni, ranging in age from 18 to 30 years old, participated in focus groups held between January and April 2020. All students identified as underrepresented minorities and 78% were first generation college students. Fifteen (65%) of the participants had not yet applied to dental school. Eight participants (35%) had applied to dental school, 3 (13%) were currently enrolled in dental school, and 5 (22%) were matriculating into dental school in Fall 2020. The following themes emerged as the most prominent challenges to applying to dental school: pre‐health advisors (e.g., lack of knowledge about the pre‐dental process and discouragement), and the cost of the application process (e.g., application fees, DAT and DAT preparation course costs, and interview costs).

Conclusion

Through pre‐dental pipeline programs, participants have access to informational resources and mentorship; however, despite participation in these programs, perceived barriers are still prevalent. Identification of the alumni's perceived barriers offer targeted areas where increased intervention may be helpful to reduce challenges and strengthen the pipeline.
Green synthesis of cerium oxide nanoparticles using Acorus calamus extract and their antibiofilm activity against bacterial pathogens
Authors: Altaf Mohammad , Manoharadas Salim , Zeyad Mohammad Tarique
Published: February 2021

The emergence of multidrug resistance in bacterial pathogens has increased drastically and it has become prevalent in clinical infections. In last few decades, there is a large gap in the discovery of new antibiotics with novel mode of action. The situation of antimicrobial resistance has become so alarming that if not action is taken, infectious diseases will become major cause of global mortality and morbidity by 2050. The growing interest of researchers in nanotechnology and their possible application in healthcare is being seen as a new hope in discovery of novel antimicrobial agents. Among various approaches employed for the nanoparticle synthesis, biological methods are considered more advantageous and environment friendly. Biofilms are considered as novel target for the development of new antimicrobial entities. In this study, cerium oxide nanoparticles (CeO2‐NPs) were synthesized using Acorus calamus aqueous extract and tested for the antibiofilm activity both against Gram +ve and Gram −ve bacteria. The average size of synthesized CeO2‐NPs was found to be 22.03 nm. The biofilms of the test bacteria were inhibited by more than 75% by the treatment with CeO2‐NPs. The quantitative biofilm data were further verified by light microscopy, electron microscopy, and confocal microscopy. The confocal and electron microscopic analysis confirmed that treatment with CeO2‐NPs reduced the development and colonization of the bacteria on solid support. Moreover, it was found that the colonization and biofilm development by test bacteria were fairly reduced on the glass surface. Moreover, a dose‐dependent inhibition of preformed biofilms was also found. The exopolysaccharides (EPS) production by the test bacteria were substantially reduced by the supplementation of CeO2‐NPs in culture media. The findings of this study highlight the efficacy of cerium oxide nanoparticles against bacterial pathogens that may be exploited for the development of new alternative antimicrobial agent.
The Nomogram of MRI‐based Radiomics with Complementary Visual Features by Machine Learning Improves Stratification of Glioblastoma Patients: A Multicenter Study
Authors: Xu Yuyun , He Xiaodong , Li Yumei , Pang Peipei , Shu Zhenyu , Gong Xiangyang
Published: February 2021

Background

Glioblastomas (GBMs) represent both the most common and the most highly malignant primary brain tumors. The subjective visual imaging features from MRI make it challenging to predict the overall survival (OS) of GBM. Radiomics can quantify image features objectively as an emerging technique. A pragmatic and objective method in the clinic to assess OS is strongly in need.

Purpose

To construct a radiomics nomogram to stratify GBM patients into long‐ vs. short‐term survival.

Study Type

Retrospective.

Population

One‐hundred and fifty‐eight GBM patients from Brain Tumor Segmentation Challenge 2018 (BRATS2018) were for model construction and 32 GBM patients from the local hospital for external validation.

Field Strength/Sequence

1.5 T and 3.0 T MRI Scanners, T1WI, T2WI, T2FLAIR, and contrast‐enhanced T1WI sequences

Assessment

All patients were divided into long‐term or short‐term based on a survival of greater or fewer than 12 months. All BRATS2018 subjects were divided into training and test sets, and images were assessed for ependymal and pia mater involvement (EPI) and multifocality by three experienced neuroradiologists. All tumor tissues from multiparametric MRI were fully automatically segmented into three subregions to calculate the radiomic features. Based on the training set, the most powerful radiomic features were selected to constitute radiomic signature.

Statistical Tests

Receiver operating characteristic (ROC) curve, sensitivity, specificity, and the Hosmer–Lemeshow test.

Results

The nomogram had a survival prediction accuracy of 0.878 and 0.875, a specificity of 0.875 and 0.583, and a sensitivity of 0.704 and 0.833, respectively, in the training and test set. The ROC curve showed the accuracy of the nomogram, radiomic signature, age, and EPI for external validation set were 0.858, 0.826, 0.664, and 0.66 in the validate set, respectively.

Data Conclusion

Radiomics nomogram integrated with radiomic signature, EPI, and age was found to be robust for the stratification of GBM patients into long‐ vs. short‐term survival.

Level of Evidence

3

Technical Efficacy Stage

2