bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of fibronectin‐loaded nanofiber scaffolds for guided pulp tissue regeneration
Authors: Leite Maria Luísa , Soares Diana Gabriela , Anovazzi Giovana , Mendes Soares Igor Paulino , Hebling Josimeri , de Souza Costa Carlos Alberto
Published: December 2020

Fibronectin (FN)‐loaded nanofiber scaffolds were developed and assessed concerning their bioactive potential on human apical papilla cells (hAPCs). First, random (NR) and aligned (NA) nanofiber scaffolds of polycaprolactone (PCL) were obtained by electrospinning technique and their biological properties were evaluated. The best formulations of NR and NA were loaded with 0, 5, or 10 μg/ml of FN and their bioactivity was assessed. Finally, FN‐loaded NR and NA tubular scaffolds were prepared and their chemotactic potential was analyzed using an in vitro model to mimic the pulp regeneration of teeth with incomplete root formation. All scaffolds tested were cytocompatible. However, NR and NA based on 10% PCL promoted the highest hAPCs proliferation, adhesion and spreading. Polygonal and elongated cells were observed on NR and NA, respectively. The higher the concentration of FN added to the scaffolds, greater cell migration, viability, proliferation, adhesion and spreading, as well as collagen synthesis and gene expression (ITGA5, ITGAV, COL1A1, COL3A1). In addition, tubular scaffolds with NA loaded with FN (10 μg/ml) showed the highest chemotactic potential on hAPCs. It was concluded that FN‐loaded NA scaffolds may be an interesting biomaterial to promote hAPCs‐mediated pulp regeneration of endodontically compromised teeth with incomplete root formation.
Weight loss, malnutrition, and cachexia in COVID‐19: facts and numbers
Authors: Anker Markus S. , Landmesser Ulf , von Haehling Stephan , Butler Javed , Coats Andrew J.S. , Anker Stefan D.
Published: December 2020

Patients with COVID‐19 disease are prone to develop significant weight loss and clinical cachexia. Three reports with altogether 589 patients that reported on weight loss and cachexia in COVID‐19 were identified. Disease severity of patients and the timing of the assessment during the disease course in these patients were variable—65 patients (11%) were intensive care treated at the time of assessment, and 183 (31%) were cared for in sub‐intensive or intermediate care structures. The frequency of weight loss ≥5% (that defines cachexia) was 37% (range 29–52%). Correlates of weight loss occurrence were reported to be raised C‐reactive protein levels, impaired renal function status, and longer duration of COVID‐19 disease. Underweight status by WHO criteria (BMI < 18.5 kg/m2) was only observed in 4% of patients analysing data from seven studies with 6661 patients. Cachexia assessment in COVID‐19 needs assessment of weight loss. COVID‐19 associated cachexia is understood to affect muscle and fat tissue as is also seen in many other chronic illness‐associated forms of cachexia. There are many factors that can contribute to body wasting in COVID‐19, and they include loss of appetite and taste, fever and inflammation, immobilization, as well as general malnutrition, catabolic–anabolic imbalance, endocrine dysfunction, and organ‐specific complications of COVID‐19 disease such as cardiac and renal dysfunction. Treatment of COVID‐19 patients should include a focus on nutritional support and rehabilitative exercise whenever possible. Specific anti‐cachectic therapies for COVID‐19 do not exist, but constitute a high medical need to prevent long‐term disability due to acute COVID‐19 disease.
Progressive loss of implant fixation in a preclinical rat model of cemented knee arthroplasty
Authors: Mann Kenneth A. , Miller Mark A. , Rossow Jeffrey K. , Tatusko Megan E. , Horton Jason A. , Damron Timothy A. , Oest Megan E.
Published: December 2020

Aseptic loosening of total knee arthroplasty continues to be a challenging clinical problem. The progression of the loosening process, from the initial well‐fixed component, is not fully understood. In this study, loss of fixation of cemented hemiarthroplasty was explored using 9‐month‐old Sprague–Dawley rats with 0, 2, 6, 12, 26 week end points. Morphological and cellular changes of cement–bone fixation were determined for regions directly below the tibial tray (epiphysis) and distal to the tray (metaphysis). Loss of fixation, with a progressive increase in cement–bone gap volume was found in the epiphysis (0.162  mm3/week), but did not progress appreciably in the metaphysis (0.007 mm3/week). In the epiphysis, there was an early and sustained elevation of osteoclasts adjacent to the cement border and development of a fibrous tissue layer between the cement and bone. There was early formation of bone around the cement in the metaphysis, resulting in a condensed bone layer without osteoclastic bone resorption or development of a fibrous tissue layer. Implant positioning was also an important factor in the cement–bone gap formation, with greater gap formation for implants that were placed medially on the tibial articular surface. Loss of fixation in the rat model mimicked patterns found in human arthroplasty where cement–bone gaps initiate under the tibial tray, at the periphery of the implant. This preclinical model could be used to study early biological response to cemented fixation and associated contributions of mechanical instability, component alignment, and periprosthetic inflammation.
Masquelet's induced membrane technique: Review of current concepts and future directions
Authors: Alford Andrea I. , Nicolaou Daemeon , Hake Mark , McBride‐Gagyi Sarah
Published: December 2020

Masquelet's induced membrane technique (MIMT) is a relatively new, two‐stage surgical procedure to reconstruct segmental bone defects. First performed by Dr. Masquelet in the mid‐1980s, MIMT has shown great promise to revolutionize critical‐sized bone defect repair and has several advantages over its alternative, distraction osteogenesis (DO). Also, its success in extremely challenging cases (defects > 15 cm) suggests that its study could lead to discovery of novel biological mechanisms that might be at play during segmental defect healing and fracture non‐union. MIMT's advantages over DO have led to a world‐wide increase in MIMT procedures over the past decades. However, MIMT often needs to be repeated and so the average initial success rate in adults lags significantly behind that of DO (86% vs 95%, respectively). The autologous foreign‐body membrane created during the first stage by the immune system's response to a polymethyl methacrylate bone cement spacer is critical to supporting the morselized bone graft implanted in the second stage. However, the biological and/or physical mechanisms by which the membrane supports graft to bone union are unclear. This lack of knowledge makes refining MIMT and improving the success rates through technique improvements and patient selection a significant challenge and hinders wider adoption. In this review, current knowledge from basic, translational, and clinical studies is summarized. The dynamics of both stages under normal conditions as well as with drug or material perturbations is discussed along with perspectives on high‐priority future research directions.
Vaccine of RANKL mutant conjugated with KLH effectively stabilizing bone metabolism and preventing trabecular microstructural degeneration in osteoporotic rats
Authors: Zhang Shudong , Wang Menglin , Li Jiantao , Li Yiyin , Zhou Jian , Tian Zhuang , Liu Changzhen , Yao Qi
Published: December 2020

Receptor activator of nuclear factor kappa‐B ligand (RANKL) is one of the key factors regulating the maturation of osteoclasts and an important target for osteoporosis treatment. A monoclonal antibody against RANKL showed effective therapeutic activity against osteoporosis by inhibiting bone resorption by osteoclasts. However, being an exogenous protein, its efficacy decreases after long‐term use, and its discontinuation increases the risk of vertebral fractures. Here, we aimed to design an active immunotherapeutic agent to induce a T‐cell dependent primary response. The agent, a mutant RANKL vaccine (mRv), was produced by cross‐linking mutant RANKL, lacking the ability to stimulate osteoclast maturation, with the carrier protein keyhole limpet hemocyanin, a neo‐antigen with a large molecular mass. Subcutaneous injection of mRv stimulated rats with ovariectomy‐induced osteoporosis to produce high titers of anti‐RANKL antibodies. The mutant RANKL vaccine decreased serum CTX‐1 and BALP levels and inhibited the microstructural degeneration of trabecular bone in osteoporotic rats. mRv overcame immune system tolerance, stimulated rats to produce therapeutic antibodies, stabilized bone metabolism, and inhibited trabecular microstructural degeneration. These findings confirm the potential of the mutant RANKL vaccine to be developed into an effective preventive and therapeutic agent for osteoporosis.
Methods to mitigate infection spread from aerosol‐generating dental procedures
Authors: Kumar Purnima S. , Geisinger Maria L. , Avila‐Ortiz Gustavo
Published: December 2020

Infection control measures play a critical role in preventing the spread of disease in healthcare settings. Concerns that SARS‐CoV‐2 (severe acute respiratory syndrome coronavirus 2), the virus that causes Coronavirus Disease 2019, may be transmitted through droplets and aerosols from both symptomatic and asymptomatic individuals has turned the spotlight on healthcare interventions that involve aerosol generation in the oral cavity, such as many dental and periodontal procedures. This commentary seeks to familiarize the dental practitioner with various infection control methods that may be implemented to mitigate spread of infection in dental settings through aerosol‐generating dental procedures
Thresholds in catchment nitrogen load for shifts from seagrass to nuisance macroalgae in shallow intertidal estuaries
Authors: Robertson Ben P , Savage Candida
Published: December 2020

Eutrophication of shallow coastal ecosystems often manifests as dense mats of opportunistic macroalgae, degraded underlying sediments and displacement of ecologically important primary producers including seagrass beds. Ecological thresholds of drivers that cause these shifts in ecosystem state are needed to manage eutrophication symptoms before tipping points are crossed. This study quantifies total nitrogen (TN) load thresholds for abrupt changes in ecologically important seagrass habitat and the appearance of nuisance macroalgae as a function of estimated catchment TN load to shallow, intertidal estuaries in New Zealand. Results indicate that the extents of both macrophyte types are strongly governed by increasing TN load to the estuaries, while total suspended sediment load was not significant alone or as an interaction term. Seagrass extent was unpredictable below a critical TN load envelope (< 50 mg N m−2 d−1), likely because there are additional factors than TN that influence seagrass cover, but once surpassed, seagrass became restricted to less than 10% of intertidal area or absent. Conversely, nuisance macroalgae was predominantly absent unless TN load exceeded 41.15 ± 21.1 mg N m−2 d−1, expanding in extent by 2.7% of intertidal area for every 50 mg N m−2 d−1 increase above threshold levels. This research underscores the importance of managing diffuse nitrogen inputs to safeguard the structure and function of shallow estuarine ecosystems before tipping points in dominant macrophyte type are crossed.
On the Possibility of Different Reactivity of Growing Radicals in Controlled and Free Radical Polymerizations. The Concept of the Reaction Cage in Controlled Radical Polymerization
Authors: Szymanski Ryszard
Published: December 2020

In some reversible deactivation radical polymerization (RDRP) processes retention of chain‐end functionality appears to be higher than expected based on the estimated rate constants of propagation and termination. In the recent paper, Ballard and Asua explained this observation using their concept of the probability density functions of the termination reactions, dependent on the initial diffusion stage of radicals being the nearest neighbors. Here, a new explanation of the observed phenomenon is proposed, alternative to their proposition. The presented hypothesis assumes interaction of growing radical with the RDRP deactivator, resulting in two types of radicals.
Identification of invisible ischemic stroke in noncontrast CT based on novel two‐stage convolutional neural network model
Authors: Wu Guoqing , Chen Xi , Lin Jixian , Wang Yuanyuan , Yu Jinhua
Published: December 2020

Purpose

Early identification of ischemic stroke lesion regions plays a vital role in its treatments like thrombolytic therapy and patients’ recovery. Noncontrast computed tomography (ncCT) is the most widespread imaging modality in emergency departments. Unfortunately, it is extremely hard to distinguish the lesion from healthy tissue during the hyper‐acute phase of stroke. In this paper, a two‐stage convolutional neural network‐based method was proposed to identify the invisible ischemic stroke from ncCT.

Methods

In order to combine the global and local information of images effectively, a cascaded structure with two coordinated networks was used to detect the suspicious stroke regions on the whole and optimize the detailed localization. In the first stage, an end‐to‐end U‐net with adaptive threshold was proposed to integrate global position, symmetry and gray texture information to detect the suspicious regions. After reducing the interference from most normal regions, a ResNet‐based patch classification network was used to eliminate some false positive samples on suspicious regions by mining deeper image features, contributing to a more precise localization of stroke. Finally, a MAP model was used to optimize the result by combining the classification results of each patch with their spatial constraint information.

Results

Three independent experiments, that is, training and testing on dataset from one hospital, on the combination of two, and on the two respectively, were performed on a total of 277 cases from two hospitals to validate the proposed model, The proposed method achieved identification accuracy of 91.89%, 87.21%, and 85.71% in the three experiments, and the final localization accuracy in terms of precise localization of stroke were 82.35%, 83.02%, and 81.40%, respectively, which indicated the robustness and clinical values of the method.

Conclusions

There are some deep image feature differences between stroke region and normal region on ncCT images. The proposed two‐stage convolutional neural network model can well seize these features and use them to effectively identify and locate stroke.
Evaluation of carbon nanotube x‐ray source array for stationary head computed tomography
Authors: Spronk Derrek , Luo Yueting , Inscoe Christina R. , Lee Yueh Z. , Lu Jianping , Zhou Otto
Published: December 2020

Purpose

Stationary computed tomography (s‐CT) conceptually offers several advantages over existing rotating gantry‐based CT. Over the last 40 yr, s‐CT has been investigated using different technological approaches. We are developing a s‐CT system specifically for head/brain imaging using carbon nanotube (CNT)‐based field emission x‐ray source array technology. The noncircular geometry requires different assessment approaches as compared to circular geometries. The purpose of the present study is to investigate whether the CNT source array meets the requirements for stationary head CT (s‐HCT).

Methods

Multiple prototype CNT x‐ray source arrays were manufactured based on the system requirements obtained from simulation. Source characterization was performed using a benchtop setup consisting of an x‐ray source array with 45 distributed focal spots, each operating at 120 kVp, and an electronic control system (ECS) for high speed control of the x‐ray output from individual focal spots. Due to the forward‐angled geometry of the linear anode, the projected focal spot shape is expected to vary at wide angle views. A pinhole method was implemented to determine the effective focal spot size (FSS) in the imaging plane at a range of angular viewpoints with a flat panel detector. The output spectrum and half value layer (HVL) were also evaluated for a range of viewing angles to characterize the beam quality across the fan‐beam. Dosimetry was performed on a simulated scan to evaluate total exposure.

Results

The prototype CNT x‐ray source array demonstrated adequate specifications for a s‐HCT imaging machine. The source array was operated at 120 kVp with long‐term stability over a full year of regular laboratory use. Multiple cathode current measurements were used to confirm submicrosecond accuracy with regards to exposure time and subsequently dose control. All 45 focal spots were measured with an average value of 1.26 (±0.04) mm × 1.21 (±0.03) mm (equivalent to IEC 1,0). The x‐ray spectrum was found to be appropriately filtered based on sources used in existing rotary CT systems. A stable and reliable output of 0.04 mAs per emitter and a resulting dose of 0.015 mGy per projection were observed over several months of rigorous phantom imaging. Dose per projection was regulated by the ECS and measured with ±0.5% tolerance.

Conclusions

The CNT x‐ray source array was found to meet the requirements for the proposed stationary head CT scanner, with regard to FSS, beam quality, and dose precision. The remaining challenges are related to the overall system design of a nonrotating CT scanner with distributed sources. The next phase of the project will incorporate multiple CNT source arrays with multirow detectors in a proof‐of‐concept study and analysis of a fully functional s‐HCT system.
Quantitative laryngeal electromyography parameters may correlate with improved outcomes following botulinum toxin injection for spasmodic dysphonia
Authors: Dwyer Christopher D. , Leclerc Andrée‐Anne , Nandedkar Sanjeev D. , Young VyVy N. , Rosen Clark A.
Published: December 2020

Background

Despite use of qualitative laryngeal electromyography (LEMG) guided botulinum toxin A (BoNT‐A) injection for treatment of adductor spasmodic dysphonia (AdSD), unsatisfactory injections and complete “misses” remain problematic. We aimed to determine if the quantitative LEMG measure of number of small segments (NSS) correlates with voice outcomes following (BoNT‐A injection for AdSD.

Methods

Automated quantitative LEMG analysis was performed during electromyography (EMG) ‐guided BoNT‐A injection into the thyroarytenoid‐lateral cricoarytenoid muscle complex for treatment of AdSD. Pre‐injection phonatory NSS values were correlated with clinical voice outcomes and patient reported injection results.

Results

Quantitative LEMG measures were obtained for 45 AdSD patients (28 female, mean age 60.8 ± 12.8 years) during EMG‐guided BoNT‐A injection. Mean sampled NSS during phonation immediately prior to BoNT‐A injection was 524 ± 323 (range: 2–904). Mean follow up was 36.5 ± 9.4 days; one patient was lost to follow‐up. In comparison to their previous BoNT‐A injection, the current injection was rated as worse, same, and better by 13 (29.5%), 25 (56.8%), and 6 (13.6%) patients, respectively. All 4 (9.1%) patients with NSS < 200 rated their BoNT‐A injection result as worse than previous, and change in Voice Handicap Index‐10 (VHI‐10) scores were worse or without change.

Conclusions

Aiming for an NSS value greater than 200 during phonation prior to BoNT‐A toxin injection for AdSD may reduce unfavorable voice outcomes.
Emerging tri‐s‐triazine‐based graphitic carbon nitride: A potential signal‐transducing nanostructured material for sensor applications
Authors: Chouhan Raghuraj Singh , Jerman Ivan , Heath David , Bohm Sivasambu , Gandhi Sonu , Sadhu Veera , Baker Syed , Horvat Milena
Published: December 2020

Today, tris‐s‐triazine based graphitic carbon nitride (g‐C3N4) is a new research hot topic. It has a unique electronic band structure, high physicochemical stability, large surface area, and is “earth‐abundant.” These and other properties have made it a highly researched material especially for visible light photocatalysis and photodegradation applications and as the starting material from which to develop novel electrochemical sensing platforms. In this review, the state‐of‐the‐art technologies utilizing tris‐s‐triazine graphitic carbon nitride as a tailorable signal‐transducing nanostructured material for sensing applications is presented in detail. Initially, the electronic structure of g‐C3N4, morphologies, doping, heterojunctions, its combination with other carbon materials, and defect formation, is described, which is followed by a discussion on its role in electrochemiluminescence, photoelectrochemical, fluorescence sensors and gas sensors as a signal transducer with appropriate examples. This review concludes with a discussion summarizing state‐of‐the‐art and both future perspectives and challenges at the cutting edge of this research.
Predictors of death within 6 months of stroke onset: A model with Barthel index, platelet/lymphocyte ratio and serum albumin
Authors: Sha Ling , Xu Tiantian , Ge Xijuan , Shi Lei , Zhang Jing , Guo Huimin
Published: December 2020

Aims

To develop and internally validate a nomogram to predict the risk of death within 6 months of onset of stroke in Chinese. Identifying risk factors with potentially direct effects on the nomogram will improve the quality of risk assessment and help nurses implement preventive measures based on patient‐specific risk factors.

Design

A retrospective study.

Methods

We performed a least absolute shrinkage and selection operator (LASSO) regression modelling and multivariate logistic regression analysis to establish a prediction model of death risk in stroke patients within 6 months of onset. LASSO and time‐dependent Cox regression models were further used to analyse the 6‐month survival of stroke patients. Data were collected from 21 October 2013–6 May 2019.

Results

The independent predictors of the nomogram were Barthel index (odds ratio (OR) = 0.980, 95% confidence interval (CI) = 0.961–0.998, p = .03), platelet/lymphocyte ratio (OR = 1.005, 95% CI = 1.000–1.010, p = .04) and serum albumin (OR = 0.854, 95% CI = 0.774–0.931, p < .01). This model showed good discrimination and consistency, and its discrimination evaluation C‐statistic was 0.879 in the training set and 0.891 in the internal validation set. The DCA indicated that the nomogram had a higher overall net benefit over most of the threshold probability range. The time‐dependent Cox regression model established the impact of the time effect of the age variable on survival time.

Conclusions

Our results identified three predictors of death within 6 months of stroke in Chinese. These predictors can be used as risk assessment indicators to help caregivers performing clinical nursing work, and in clinical practice, it is suggested that nurses should evaluate the self‐care ability of stroke patients in detail. The constructed nomogram can help identify patients at high risk of death within 6 months, so that intervention can be performed as early as possible.
Therapeutic approaches against coronaviruses acute respiratory syndrome
Authors: Servidio Camilla , Stellacci Francesco
Published: December 2020

Coronaviruses represent global health threat. In this century, they have already caused two epidemics and one serious pandemic. Although, at present, there are no approved drugs and therapies for the treatment and prevention of human coronaviruses, several agents, FDA‐approved, and preclinical, have shown in vitro and/or in vivo antiviral activity. An in‐depth analysis of the current situation leads to the identification of several potential drugs that could have an impact on the fight against coronaviruses infections. In this review, we discuss the virology of human coronaviruses highlighting the main biological targets and summarize the current state‐of‐the‐art of possible therapeutic options to inhibit coronaviruses infections. We mostly focus on FDA‐approved and preclinical drugs targeting viral conserved elements.
Hybrid Lead Halide Perovskite Films with Large Grain Size Via Spin‐Coating Free Fabrication
Authors: Liu Wenyan , Ma Pengfei , Xu Jiaying , Wang Changhao , Wang Chen , Qu Minglei , Wen Shanpeng
Published: December 2020

Herein, a spin‐coating‐free method to deposit CH3NH3PbI3 perovskite films with large grains is demonstrated. The effect of processing temperature on the property of hybrid lead halide perovskite films is investigated. It is found that the grain domain size is enlarged by increasing processing temperature. Dense and uniform CH3NH3PbI3 films with grain domain size close to 1 mm are obtained using this method. A higher processing temperature also promotes the conversion from precursors solution to perovskite, but excessive temperature induces a poor crystalline state. About 150 °C is proved to be close to the optimal processing temperature to form perovskite films with less defect density, lower charge recombination, and longer charge carrier lifetimes. Space‐charge‐limited current method is used to investigate the charge transport efficiency based on CH3NH3PbI3 perovskite films. The results show that both the electron and hole mobility improve remarkably as the processing temperature increases.
Mega doses of retinol: A possible immunomodulation in Covid‐19 illness in resource‐limited settings
Authors: Midha Ish K. , Kumar Nilesh , Kumar Amit , Madan Taruna
Published: December 2020

Of all the nutrients, vitamin A has been the most extensively evaluated for its impact on immunity. There are three main forms of vitamin A, retinol, retinal and retinoic acid (RA) with the latter being most biologically active and all‐trans‐RA (ATRA) its main derivative. Vitamin A is a key regulator of the functions of various innate and adaptive immune cells and promotes immune‐homeostasis. Importantly, it augments the interferon‐based innate immune response to RNA viruses decreasing RNA virus replication. Several clinical trials report decreased mortality in measles and Ebola with vitamin A supplementation.During the Covid‐19 pandemic interventions such as convalescent plasma, antivirals, monoclonal antibodies and immunomodulator drugs have been tried but most of them are difficult to implement in resource‐limited settings. The current review explores the possibility of mega dose vitamin A as an affordable adjunct therapy for Covid‐19 illness with minimal reversible side effects. Insight is provided into the effect of vitamin A on ACE‐2 expression in the respiratory tract and its association with the prognosis of Covid‐19 patients. Vitamin A supplementation may aid the generation of protective immune response to Covid‐19 vaccines. An overview of the dosage and safety profile of vitamin A is presented along with recommended doses for prophylactic/therapeutic use in randomised controlled trials in Covid‐19 patients.
Multifunctionalized Gold Sub‐Nanometer Particles for Sensitizing Radiotherapy against Glioblastoma
Authors: Dong Cheng‐Yuan , Hong Sheng , Zheng Di‐Wei , Huang Qian‐Xiao , Liu Fu‐Sheng , Zhong Zhen‐Lin , Zhang Xian‐Zheng
Published: December 2020

Glioblastoma is the most common lethal malignant intracranial tumor with a low 5‐year survival rate. Currently, the maximal safe surgical resection, followed by high‐dose radiotherapy (RT), is a standard treatment for glioblastoma. However, high‐dose radiation to the brain is associated with brain injury and results in a high fatality rate. Here, integrated pharmaceutics (named D‐iGSNPs) composed of gold sub‐nanometer particles (GSNPs), blood‐brain barrier (BBB) penetration peptide iRGD, and cell cycle regulator α‐difluoromethylornithine is designed. In both simulated BBB and orthotopic murine GL261 glioblastoma models, D‐iGSNPs are proved to have a beneficial effect on the BBB penetration and tumor targeting. Meanwhile, data from cell and animal experiments reveal that D‐iGSNPs are able to sensitize RT. More importantly, the synergy of D‐iGSNPs with low‐dose RT can exhibit an almost equal therapeutic effect with that of high‐dose RT. This study demonstrates the therapeutic advantages of D‐iGSNPs in boosting RT, and may provide a facile approach to update the current treatment of glioblastoma.
Improved Light Harvesting and Efficiency for Overall Water Splitting by Embedding TiO2 Transition Layer in GaP/Ga2O3/Ga2Se3 Multijunction Photocatalyst
Authors: Wang Meng , Lu Gongxuan
Published: December 2020

Photocatalytic water splitting to generate hydrogen has attracted great attention due to its potential for conversion and storage of solar energy. To obtain high efficiency of water splitting under solar irradiation, the catalyst should have good enough absorption in the visible region, excellent charge transfer ability, and satisfied stability during the photoreaction. Herein, the significant absorption promotion of the catalyst to a longer wavelength is achieved by simultaneously in situ selenylation and phosphorization of Ga2O3. The formation of narrow‐bandgap Ga2Se3 and GaP layers makes the catalyst absorb visible light up to 640 from 282 nm. In addition, by embedding a TiO2 transition layer between Ga2O3 and Ga2Se3, better crystal match in the catalyst is accomplished, which leads to better structural stability and the formation of better charge transfer route. Compared with GaP/Ga2O3/Ga2Se3, the GaP/TiO2/Ga2O3/TiO2/Ga2Se3 photocatalyst exhibits a much higher photocatalytic H2 evolution activity and achieves a higher apparent quantum efficiency (≈4% at 430 nm). Moreover, the TiO2 transition layer also reduces the crystal mismatch between GaP and Ga2O3. Herein, the advantage of utilizing the transition layer in multijunction photocatalyst to increase the photocatalytic activity and strengthen the stability of the assembled catalyst for overall water splitting is demonstrated.
Silicon Determination in Stainless Steels via Inductively Coupled Plasma Optical Emission Spectrometry: An Overview based on Experimental Data
Authors: Franciscono Andrea , Rollet Simona
Published: December 2020

Silicon determination on stainless steel alloys via inductively coupled plasma optical emission spectrometry (ICP‐OES) is a topic not yet fully explored in the literature. In the extreme acidic conditions necessary for the dissolution of these samples, phenomena such as polymerization and aggregation of silicon particles may strongly affect the result. A low recovery may be expected if the analytical steps are not properly conducted. Herein, different experimental layouts with certified reference materials are devised to demonstrate the weak spots of this technique and to provide a clear understanding on how to cope with this issue.
3D Covalent Organic Frameworks Based on Polycyclic Aromatic Hydrocarbons for Reversible Oxygen Capture
Authors: Zhang Minghao , Fang Jing , Liu Yaozu , Wang Yujie , Liao Li , Tang Lingxue , Zhu Liangkui , Qiu Shilun , Fang Qianrong
Published: December 2020

Singlet oxygen, as a kind of reactive oxygen species, plays an important role in organic synthesis and biological processes. However, these excited oxygen molecules have a short life and high reactivity; thus it is a great challenge to capture singlet oxygen. Here, for the first time two functionalized 3D covalent organic frameworks (3D COFs) with polycyclic aromatic hydrocarbons, termed as JUC‐575 and JUC‐576, for reversible singlet oxygen capture and release are reported. These 3D COFs, constructed from anthracene or naphthalene derivatives, can effectively trap singlet oxygen through chemical transformation to generate the corresponding endoperoxide COFs (EPO‐COFs). Furthermore, it is also confirmed that the reversible oxygen capture and release between the parent COFs and EPO‐COFs can be well controlled by switching the UV–vis irradiation. This study thus broadens the potential applications of 3D functionalized COFs as molecular carriers in biology and organic synthesis.
Regulation by FLOWERING LOCUS T and TERMINAL FLOWER 1 in Flowering Time and Plant Architecture
Authors: Liu Lu , Xuan Lijie , Jiang Yupeng , Yu Hao
Published: December 2020

The conversion from vegetative to inflorescence shoot apical meristem is one of the key developmental switches in flowering plants. This transition is modulated by various environmental and endogenous stimuli and controlled by sophisticated regulatory networks. Regulation of flowering time and inflorescence architecture has a great impact on plant reproductive success and significantly influences plant biomass and fitness. FLOWERING LOCUS T (FT), a mobile protein identified as a major component of florigen, promotes the transition to flowering, whereas its homologous protein TERMINAL FLOWER 1 (TFL1) functions oppositely. Studies in various species reveal that FT and TFL1 play universal and multifaceted roles in a wide range of developmental processes in plants. Hence, modulations of FT/TFL1 and their regulatory pathways have a considerable impact on plant development and crop domestication. Herein, an overview of the molecular basis underlying the regulation of FT/TFL1 expression and modulation of their protein trafficking and the relevant mechanisms in flowering time control and meristem development is provided. Whenever applicable, their functional conservation and divergence in various plant species are also discussed.
Ras/Raf/MEK/ERK pathway axis mediated neurotoxicity induced by high‐risk pesticide residue‐Avermectin
Authors: Zhu Ting , Liu Xu , Song Jian , Li Dong , Pang Xiao‐Jing , Wang Sheng‐Hui , Li Qing‐Rong , Fu Dong‐Jun , Zhang Sai‐Yang , Xie Han‐Zhong
Published: December 2020

Pesticide residues have become a healthy threaten of human beings. Among the pesticides, many of them have neurotoxicity. Extracellular Regulated Protein Kinases (ERK) pathway is an important signaling pathway that regulates a variety of downstream progress. In this work, peach (PRUNUS persica) and cherry (PRUNUS cerasus) were sampled from over 300 plantations in China and assessed for the residue risk. In mechanism studies, high‐risk pesticide Avermectin showed a high activity inhibiting three neurotoxicity models, SH‐SY5Y, PC‐12 and SK‐N‐SH cells. At protein levels, ERK pathway proteins and their downstream proteins were obviously down‐regulated. Moreover, the effects of low‐dose Avermectin can be accumulated at protein levels in the low‐dose long‐term chronic toxicology detection.
Detoxification of fermentable broth with activated biocarbon resulting from pyrolysis of agroforestry residues
Authors: Martins Ayrton F. , Villetti Marcos A. , Mortari Sérgio R. , Pedroso Giovanni B. , Saldanha Loisleini F. , Rambo Magale K. D.
Published: December 2020

Carbon‐like materials from pyrolysis (<500°C) of agricultural leftovers (rice husks, eucalyptus sawdust and peach stones) were submitted to steam activation and the expected adsorbent properties evaluated by means of a chemical method (methylene blue) and physically characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and surface area (BET). Batch experiments were carried out to check the pH effect on the adsorption of methylene blue, by evaluating the respective equilibrium isotherms (Langmuir, Freundlich and Temkin). The steam‐activated biocarbons showed significant adsorbent capacity, which increased along with pH. The best performance was achieved by the activated biocarbon from peach stones, which showed adsorptive properties similar to activated carbon market. The suitable detoxification efficiency of untreated broths with activated biocarbon, and an increase in the required fermentability, supports the potential use of these adsorptive bioproducts from agricultural leftovers. The profitable use of agricultural waste materials is actually a welcome strategy for consolidating the biorefinery concept as well as ensuring planetary sustainability.

Practitioner points

Use of biomass residues for detoxification of fermentable broth.

The activated biocarbons showed significant adsorbent capacity similar to activated carbon market.

The results revealed the potential of the biomass residues as a promising source within bio‐refineries.
Disorderly Identities: University Rankings and the Re-ordering of the Academic Mind
Authors: Nixon Jon
Published: December 2020

This chapter focuses on the use of university rankings as a means of ostensibly achieving increased transparency and covertly introducing a competitive market which has impacted on the sector as a whole, on institutions, and on individuals. The systemic characteristics of this new and now increasingly dominant market-driven order are outlined, followed by an exposition of how that order has impacted on the mind-set of academic practitioners by defining the norms of academic professionalism and academic practice. A new kind of orderliness now circumscribes and defines what it means to be an academic. Some of the emergent but pressing alternatives to this identity-kit of orderliness are suggested: disorderly identities that transgress the spatial boundaries of the dominant order, challenge its control of the chronology of that order, and begin to constitute participative and non-hierarchical foci of pedagogical action and participative research.
Becoming World Class: What It Means and What It Does
Authors: Benner Mats
Published: December 2020

On the basis of a critical survey of university strategies, it is argued that universities reify and objectify “world class” and turn it into absolute and precisely defined goals (location in ranking hierarchies, publication patterns, number of start-ups and licens-es, etc.) and that this in turn is based on a skewed reading of the ascendancy of some universities (notably leading US higher education institutions) to that level. The notion of a “world class university” may therefore be self-defeating as it entails even closer monitoring, adaptation and adoption of indicators and steering that is outlined accordingly.
The Paradox of the Global University
Authors: Stevens Mitchell L. , Giebel Sonia
Published: December 2020

No university of ambition officially claims to be local. Touting international reach and reputation is a nearly essential feature of university strategic planning worldwide. Yet being a global university is paradoxical. Academic institutions historically are servants of particular cities, regions, and nations, and one of their essential functions has been to connect particular places with world affairs. International rankings regimes, the search for tuition revenue among schools in a few large markets, and the remarkable consistency with which nations pursue status through higher education: all of these deepen the implication of universities in the fate and future of particular locales.
The Evidential Conditional
Authors: Crupi Vincenzo , Iacona Andrea
Published: December 2020

This paper outlines an account of conditionals, theevidential account, which rests on the idea that a conditional is true just in case its antecedent supports its consequent. As we will show, the evidential account exhibits some distinctive logical features that deserve careful consideration. On the one hand, it departs from the material reading of ‘if then’ exactly in the way we would like it to depart from that reading. On the other, it significantly differs from the non-material accounts which hinge on the Ramsey Test, advocated by Adams, Stalnaker, Lewis, and others.
Real world analysis of high-cut-off (HCO) hemodialysis with bortezomib-based backbone therapy in patients with multiple myeloma and acute kidney injury
Authors: Steiner N. , Abdel Hamid A. , Kronbichler A. , Neuwirt H. , Myslivecek M. , Kollar M. , Lachmanova J. , Rysava R. , Hruskova Z. , Spicka I. , Willenbacher W. , Nachbaur D. , Wolf D. , Tesar V. , Gunsilius E.
Published: December 2020

Background

In patients with multiple myeloma (MM) free light chain-induced cast nephropathy is a serious complication associated with poor survival. High-cut-off (HCO) hemodialysis can reduce the amount of serum free light chains (sFLC), but data on its impact on clinical outcome is limited and contradictory. To gain further insights we collected real world data from two major myeloma and nephrology centers in Austria and the Czech Republic.

Methods

Sixty-one patients with MM and acute kidney injury, who were treated between 2011 and 2019 with HCO hemodialysis and bortezomib-based MM therapy, were analyzed.

Results

The median number of HCO hemodialysis sessions was 11 (range 1–42). Median glomerular filtration rate at diagnosis was 7 ± 4.2 ml/min/1.73m2. sFLC after the first HCO hemodialysis decreased by 66.5% and by 89.2% at day 18. At 3 and 6 months, 26 (42.6%) and 30 (49.2%) of patients became dialysis-independent.

Conclusion

The widely used strategy combining HCO hemodialysis and bortezomib-based antimyeloma treatment is dissatisfactory for half of the patients undergoing it and clearly in need of improvement.
Beneficial effect of retigabine on memory in rats receiving ethanol
Authors: Zwierzyńska Ewa , Krupa-Burtnik Agata , Pietrzak Bogusława
Published: December 2020

Background

Retigabine belongs to the novel generation of antiepileptic drugs but its complex mechanism of action causes that the drug might be effective in other diseases, for instance, alcohol dependence. It is known that ethanol abuse impaired the function of brain structures associated with memory and learning such as the hippocampus. In our previous study, retigabine reduced hippocampal changes induced by ethanol in the EEG rhythms in rabbits. This study is focused on the impact of retigabine on memory processes in male rats receiving alcohol.

Methods

Memory was evaluated in various experimental models: Morris water maze, Contextual, and Cued Fear Conditioning tests. Retigabine was administered for 3 weeks directly to the stomach via oral gavage at a dose of 10 mg/kg. Rats received also 20% ethanol (5 g/kg/day in two doses) via oral gavage for 3 weeks and had free access to 5% ethanol in the afternoon and at night. Morris water maze was performed after 1 and 3 weeks of ethanol administration and after 1 week from the discontinuation of ethanol administration. Contextual and Cued Fear Conditioning tests were carried out after 24 h and 72 h of alcohol discontinuation.

Results

The drug significantly decreased ethanol-induced memory disturbances during alcohol administration as well as slightly improved learning processes after the discontinuation of ethanol administration.

Conclusions

This beneficial effect of retigabine-ethanol interaction on memory may be a relevant element of the drug’s impact on the development of addiction.
Canals and Orchards: The Impact of Transport Network Access on Agricultural Productivity in Nineteenth-Century Bangkok
Authors: Chankrajang Thanyaporn , Vechbanyongratana Jessica
Published: December 2020

We assess the impact of access to Bangkok’s nineteenth-century canal network on orchard productivity using a new dataset constructed from 1880s orchard land deeds. We find that properties located adjacent to canals, which were built for purposes exogenous to orchard production, had significantly higher labor productivity than those located inland. Gaining direct access to canals led to productivity improvements through better access to markets, which in turn enhanced cultivators’ welfare. We conclude, based on a method developed by Oster (2019), that unobserved selection bias is negligible, allowing for the positive impact of canal access to be interpreted as causal.
Two‐dimensional Reconstruction of a Time‐dependent Mirror Structure from Double‐polytropic MHD Simulation
Authors: Teh Wai‐Leong , Zenitani Seiji
Published: December 2020

A new reconstruction method incorporated with pressure anisotropy parameter, , has recently been developed for magnetohydrostatic equilibria and successfully applied to recovering a two‐dimensional (2‐D) magnetic field map of mirror structures observed in the Earth's magnetosheath. Here, is assumed to be a function of magnetic field strength, , alone. The fundamental reconstruction theory assumes that the magnetic field and plasma configurations are time‐independent and 2‐D, which may not be fulfilled in the real applications to satellite observations. When the 2‐D structure is time‐dependent, the intrinsic field‐line invariant is violated so that the quantity is not constant for the same field line. This paper aims to examine the performance of the reconstruction of a time‐dependent mirror structure, using data from a 2‐D, double‐polytropic Magnetohydrodynamics (MHD) simulation. With a single‐branched fitting function for the field‐line invariant, results show that the geometry of time‐dependent mirror structure can be reasonably reconstructed, including the distribution maps of gyrotropic pressures and . As expected, the assumption of is well satisfied for the mirror structure. Additionally, another two reconstruction methods are also tested, namely, the Grad‐Shafranov reconstruction and the reconstruction. The former is considered isotropic pressure, while the latter assumes that is function of vector potential alone. As expected, these two reconstruction methods fail to recover the geometry of the mirror structure. We suggest that use of a single‐branched fitting function is more appropriate for reconstruction of a time‐dependent, wave‐like structure, regardless of which magnetohydrostatic reconstruction method is applied.
TWINS Observations of the Dynamics of Ring Currents Ion Spectra on March 17 and October 7, 2015
Authors: Shekhar S. , Perez J. D. , Ferradas C. P.
Published: December 2020

Direct comparisons between RBSP (Van Allen Probes or Radiation Belt Storm Probes) and TWINS (Two Wide‐angle Imaging Neutral‐atom Spectrometers) for the main phase of two storms, March 17 and October 7, 2015, showed agreement between the in situ ion measurements and the ion spectra from the deconvolved energetic neutral‐atom (ENA) measurements, except when O+ ions were significant. Spatial evolution of individual energy peaks in the ion spectra is studied using TWINS data. O+ ions are seen to result in intense peaks at 5–10 keV/amu in the TWINS ion spectra. These ion populations are confined to low L shells (L < 5) and localized in the premidnight sector. When H+ ions are significant, the low energy peaks (<25 keV/amu) are found to be less intense than the high energy peaks (>25 keV/amu), located at L > 4 and localized within the premidnight sector. During times of rapidly varying AE indices, two spatially distinct peaks, between 3–5RE and 6–8RE, are observed for the ions with energies >25 keV/amu. The outer peak appears for a few hours and fades while the inner peak is more stable. These structures are found to be consistent with particle injections observed in the RBSP data. When double peaked structures are swept off, low energy ions accumulate in the premidnight to midnight sectors whereas high energy ions are located premidnight to postmidnight sectors. Faster drift orbits of >25 keV/amu ions may cause this kind of distribution.
Parallel Electrical Conductivity in the Topside Ionosphere Derived From Swarm Measurements
Authors: Giannattasio F. , De Michelis P. , Pignalberi A. , Coco I. , Consolini G. , Pezzopane M. , Tozzi R.
Published: December 2020

Our knowledge of the physical properties of the topside ionosphere is still incomplete. A key point still not fully understood is how field‐aligned currents are generated, evolve and dissipate in the ionosphere. Answering to this question is fundamental for a better understanding of the mechanisms regulating the coupling between magnetosphere and ionosphere and to shed light on the physical processes inherent to space weather events occurring in the Earth's ionosphere. In this framework a relevant role is played by the ionospheric conductivity. The purpose of this study is to analyze the main properties of the electrical conductivity parallel to the geomagnetic field from a climatological point of view. The statistical study of the electrical conductivity is proposed using four years of in‐situ electron density and temperature measurements at 1 Hz acquired by the European Space Agency's Swarm A satellite. Variations due to seasonal effects are also investigated. Finally, starting from observations and comparing our results with those obtained using International Reference Ionosphere model, we give a first estimation of the conductivity mainly due to particle precipitation.