bluuebunny/crossref_metadata_2025 huggingface dataset:
Collecting e‐cigarette aerosols for in vitro applications: A survey of the biomedical literature and opportunities to increase the value of submerged cell culture‐based assessments
Authors: Smart Daniel J. , Phillips Gary
Published: October 2020

Electronic nicotine delivery systems (ENDS) are being developed as potentially reduced‐risk alternatives to the continued use of combustible tobacco products. Because of the widespread uptake of ENDS—in particular, e‐cigarettes—the biological effects, including the toxic potential, of their aerosols are under investigation. Preclinically, collection of such aerosols is a prerequisite for testing in submerged cell culture‐based in vitro assays; however, despite the growth in this research area, there is no apparent standardized collection method for this application. To this end, through an Institute for in vitro Sciences, Inc. workshop initiative, we surveyed the biomedical literature catalogued in PubMed® to map the types of methods hitherto used and reported publicly. From the 47 relevant publications retrieved, we identified seven distinct collection methods. Bubble‐through (with aqueous solvents) and Cambridge filter pad (CFP) (with polar solvents) collection were the most frequently cited methods (57% and 18%, respectively), while the five others (CFP + bubble‐through; condensation; cotton filters; settle‐upon; settle‐upon + dry) were cited less often (2–10%). Critically, the collected aerosol fractions were generally found to be only minimally characterized chemically, if at all. Furthermore, there was large heterogeneity among other experimental parameters (e.g., vaping regimen). Consequently, we recommend that more comprehensive research be conducted to identify the method(s) that produce the fraction(s) most representative of the native aerosol. We also endorse standardization of the aerosol generation process. These should be regarded as opportunities for increasing the value of in vitro assessments in relation to predicting effects on human health.
Influence of doxycycline administration on rat embryonic development during organogenesis
Authors: Abd‐Allah Entsar R. , Abd El‐Rahman Heba A.
Published: October 2020

This experiment was performed to evaluate the possible embryotoxic and teratogenic effects of doxycycline during rat development. Twenty‐one female rats were used and distributed into three groups equally (seven animals/group). The low dose group received doxycycline at a dose of 5 mg/kg bw/day orally from the 6th to 14th day of gestation. The high dose group received 10 mg/kg bw/day orally for the same period, the Control group received 1 mL distilled water orally for the same period. The dams were dissected on the 20th day of gestation and their fetuses were subjected to morphological, skeletal, and histological examination. Moreover, DNA damage analysis of liver cells of pregnant rats and their fetuses or fetal skull was assessed by Comet assay. The obtained results showed a significant decrease in fetal body weight, several morphological anomalies, and severe lack of ossification on the skull bones, phalanges, and sternum bone as well as shortness in the ulna and radius bones. Histological studies of pregnant rats revealed congestion and dilatation of the central vein of the liver lobules and fatty degeneration of the hepatocytes. In addition, 20 day‐fetuses showed a marked increase of necrotic hepatocytes associated with an increased average of megakaryocytes and periportal leukocytic infiltration. Moreover, doxycycline induced a significant increase in the percentage of DNA damage and tail length of examined samples. Conclusively, doxycycline caused certain fetal abnormalities, so it is advisable to avoid using this drug during pregnancy.
Incidence of Deep Venous Thrombosis in Patients With COVID‐19 and Pulmonary Embolism
Authors: Franco‐Moreno Anabel , Herrera‐Morueco Maria , Mestre‐Gómez Beatriz , Muñoz‐Rivas Nuria , Abad‐Motos Ane , Salazar‐Chiriboga Danilo , Duffort‐Falcó Mercedes , Medrano‐Izquierdo Pilar , Bustamante‐Fermosel Ana , Pardo‐Guimera Virginia , Ulla‐Anés Mariano , Torres‐Macho Juan ,   the Infanta Leonor Thrombosis Research Group
Published: October 2020

Objectives

Several reports had observed a high risk of pulmonary embolism (PE) in patients with coronavirus disease 2019 (COVID‐19), most of them in the intensive care unit. Reported findings indicate that a direct viral‐mediated hyperinflammatory response leads to local thromboinflammation. According to those findings, the incidence of deep venous thrombosis (DVT) in patients with COVID‐19 and PE should be low. The objective of this study was to evaluate the incidence of DVT in patients with COVID‐19 who developed PE.

Methods

In this prospective observational study, consecutive patients hospitalized in the internal medicine ward with a diagnosis of COVID‐19 who developed PE were screened for DVT in the lower extremities with complete compression ultrasound.

Results

The study comprised 26 patients. Fifteen patients (57.7%) were male. The median age was 60 years (interquartile range, 54–73 years). Compression ultrasound findings were positive for DVT in 2 patients (7.7%; 95% confidence interval, 3.6%–11.7%). Patients with DVT had central and bilateral PE. In both, venous thromboembolism was diagnosed in the emergency department, so they did not receive previous prophylactic therapy with low‐molecular‐weight heparin. Patients without DVT had higher median d‐dimer levels: 25,688 μg/dL (interquartile range, 80,000–1210 μg/dL) versus 5310 μg/dL (P < .05).

Conclusions

Our study showed a low incidence of DVT in a cohort of patients with COVID‐19 and PE. This observation suggests that PE in these patients could be produced mainly by a local thromboinflammatory syndrome induced by severe acute respiratory syndrome coronavirus 2 infection and not by a thromboembolic event.
Predictive Nomogram for the Necessity of Tracheotomy During Oral and Oropharyngeal Cancer Surgery
Authors: Xu Siyuan , Wang Kai , Liu Kan , Liu Yang , Huang Ying , Zhang Ye , Wang Xiaolei , Xu Zhengang , Liu Shaoyan , Liu Jie
Published: October 2020

Objectives/Hypothesis

The individualized risk of airway obstruction after head and neck cancer surgery is unclear, especially oral and oropharyngeal cancer. The study aimed to establish an individualized predictive model for the necessity of temporary tracheotomy in these patients.

Methods

Patients who underwent oral and oropharyngeal cancer surgery from 1999 to 2019 were retrospectively reviewed. A nomogram was developed and validated in patients treated from 1999 to 2009 and 2010 to 2019, respectively.

Results

In total, 1551 patients were included. Oropharyngeal cancer, large tumor, midline crossing, preoperative radiation, mandibulectomy, flap reconstruction, and neck dissection were independent risk factors of postoperative airway obstruction in the training group (n = 707). A nomogram incorporating these factors had a C‐index of 0.931 and was validated in the testing group (n = 844) (C‐index, 0.918). Good calibration curves were observed in both groups.

Conclusions

The nomogram successfully predicted the individual risk of postoperative airway obstruction for patients with oral and oropharyngeal cancer.

Level of Evidence

4. Laryngoscope, 131:E1489–E1495, 2021
Quantification of Aerosol Concentrations During Endonasal Instrumentation in the Clinic Setting
Authors: Murr Alexander T. , Lenze Nicholas R. , Gelpi Mark W. , Brown William C. , Ebert Charles S. , Senior Brent A. , Thorp Brian D. , Kimple Adam J. , Zanation Adam M.
Published: October 2020

Objective

Recent anecdotal reports and cadaveric simulations have described aerosol generation during endonasal instrumentation, highlighting a possible risk for transmission of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) during endoscopic endonasal instrumentation. This study aims to provide a greater understanding of particle generation and exposure risk during endoscopic endonasal instrumentation.

Study Design

Prospective quantification of aerosol generation during office‐based nasal endoscopy procedures.

Methods

Using an optical particle sizer, airborne particles concentrations 0.3 to 10 microns in diameter, were measured during 30 nasal endoscopies in the clinic setting. Measurements were taken at time points throughout diagnostic and debridement endoscopies and compared to preprocedure and empty room particle concentrations.

Results

No significant change in airborne particle concentrations was measured during diagnostic nasal endoscopies in patients without the need for debridement. However, significant increases in mean particle concentration compared to preprocedure levels were measured during cold instrumentation at 2,462 particles/foot3 (95% CI 837 to 4,088; P = .005) and during suction use at 2,973 particle/foot3 (95% CI 1,419 to 4,529; P = .001). In total, 99.2% of all measured particles were ≤1 μm in diameter.

Conclusion

When measured with an optical particle sizer, diagnostic nasal endoscopy with a rigid endoscope is not associated with increased particle aerosolization in patient for whom sinonasal debridement is not needed. In patients needing sinonasal debridement, endonasal cold and suction instrumentation were associated with increased particle aerosolization, with a trend observed during endoscope use prior to tissue manipulation. Endonasal debridement may potentially pose a higher risk for aerosolization and SARS‐CoV‐2 transmission. Appropriate personal protective equipment use and patient screening are recommended for all office‐based endonasal procedures.

Level of Evidence

3 Laryngoscope, 131:E1415–E1421, 2021
Near‐Infrared Fluorescence Imaging in the Identification of Parathyroid Glands in Thyroidectomy
Authors: Takahashi Takeshi , Yamazaki Keisuke , Ota Hisayuki , Shodo Ryusuke , Ueki Yushi , Horii Arata
Published: October 2020

Objectives/Hypothesis

To assess the ability of near‐infrared fluorescence imaging (NIFI) to identify parathyroid glands (PGs) among histologically proven PG/non‐PG specimens compared with a surgeon's visual acumen, and to determine NIFI sensitivity in detecting incidentally resected PGs from thyroidectomy specimens, compared to the surgeon's visual inspection.

Study Design

Prospective study.

Methods

With mean age of 61 years, 36 patients with various thyroid diseases were enrolled. Possible PGs (n = 28) and lymph nodes (n = 32) were identified by the experienced surgeon's visual inspection. Using NIFI, 15 PGs were further identified from thyroidectomy specimens. For these 75 specimens, the surgeon's judgments (PG vs. non‐PG) were recorded. Histological evaluation was performed after examining the NIFI auto‐fluorescence of each specimen.

Results

There were no significant differences in sensitivity, specificity, positive predictive value, and negative predictive value between the surgeon's visual inspection and NIFI in identifying PGs, with values of 100%/97.1%, 85.0%/87.5%, 85.4%/87.2%, and 100%/97.2%, respectively. The sensitivity of NIFI (82.9%) for detection of PGs from thyroidectomy specimens was significantly higher than that of the surgeon's visual inspection (61.0%). False negative specimens contained bleeding/congestion and/or encapsulation by thick tissues, whereas false positive specimens contained electrocoagulated tissues.

Conclusions

NIFI showed results comparable to the experienced surgeon's visual inspection in identifying PGs. This could benefit novice surgeons. NIFI may be useful for experienced surgeons to locate incidentally resected PGs within thyroidectomy specimens for auto‐transplantation. Prevention of intra‐gland bleeding and congestion, careful removal of thick capsules, and bloodless surgeries without electrocoagulation are important for reducing false positive and false negative results. Laryngoscope, 131:1188–1193, 2021
Under‐ice mesocosms reveal the primacy of light but the importance of zooplankton in winter phytoplankton dynamics
Authors: Hrycik Allison R. , Stockwell Jason D.
Published: October 2020

Factors that regulate planktonic communities under lake ice may be vastly different from those during the open‐water season. Expected changes in light availability, ice cover, and snowfall associated with climate change have accelerated the need to understand food web processes under ice. We hypothesized that light limitation (bottom‐up control) outweighs zooplankton grazing (top‐down control) influence on phytoplankton biovolume and community structure under ice in a north temperate lake. Using in situ under‐ice mesocosm experiments, we found that light had stronger effects on phytoplankton abundance than zooplankton, as expected. Specifically, low light limited growth of diatoms, cryptophytes, and chrysophytes. Zooplankton, however, also significantly affected some individual phytoplankton groups by decreasing diatoms and cryptophytes, in contrast to the common assumption that zooplankton grazing has negligible effects under ice. Ammonium and soluble reactive phosphorus (SRP) were lowest in high light treatments presumably through uptake by phytoplankton, whereas ammonium and SRP were highest in high zooplankton treatments, likely a result of zooplankton excretion. In situ experimental studies are commonly applied to understand food web dynamics in open‐water conditions, but are extremely rare under ice. Our results suggest that changes in the light environment under ice have significant, rapid effects on phytoplankton growth and community structure and that zooplankton may play a more active role in winter food webs than previously thought. Changes in snow and ice dynamics associated with climate change may alter the light environment in ice‐covered systems and significantly influence community structure.
The Pseudodystonia of Paroxysmal Sympathetic Hyperactivity: A Reversible Post‐Anoxic Complication
Authors: Gupta Harsh V. , Sharma Vibhash D. , Espay Alberto J.
Published: October 2020

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Determination of eddy dissipation rate by Doppler lidar in Reykjavik, Iceland
Authors: Yang Shu , Petersen Guðrún Nína , von Löwis Sibylle , Preißler Jana , Finger David C.
Published: October 2020

The temporal and spatial scale of atmospheric turbulence can be highly dynamic, requiring sophisticated methods for adequate detection and monitoring with high resolution. Doppler light detection and ranging (lidar) systems have been widely used to observe and monitor wind velocity and atmospheric turbulence profiles as Doppler lidar systems can provide continuous information about wind fields. The use of lidars in the subarctic region is particularly challenging as aerosol abundance can be very low, leading to weak backscatter signals. In the present study, we analysed data collected with a Leosphere Windcube 200S lidar system stationed in Reykjavik, Iceland, to estimate the eddy dissipation rate (EDR) as an indicator of turbulence intensity. For this purpose, we retrieved radial wind velocity observations from velocity–azimuth display scans and computed the EDR based on the Kolmogorov theory. We compared different noise filter thresholds, scan strategies and calculation approaches during typical Icelandic weather conditions to assess the accuracy and the uncertainty of our EDR estimations. The developed algorithm can process raw lidar observations, retrieve EDR and determine the qualitative distribution of the EDR. The processed lidar observations suggest that lidar observations can be of high importance for potential end‐users, for example air traffic controllers and aviation safety experts. The work is an essential step towards enhanced aviation safety in Iceland where aerosol concentration is in general low and severe turbulence occurs regularly.
Optimization of pseudo‐continuous arterial spin labeling for renal perfusion imaging
Authors: Echeverria‐Chasco Rebeca , Vidorreta Marta , Aramendía‐Vidaurreta Verónica , Cano David , Escalada Javier , Garcia‐Fernandez Nuria , Bastarrika Gorka , Fernández‐Seara María A.
Published: October 2020

Purpose

To evaluate labeling efficiency of pseudo‐continuous arterial spin labeling (PCASL) and to find the gradient parameters that increase PCASL robustness for renal perfusion measurements.

Methods

Aortic blood flow was characterized in 3 groups: young healthy volunteers (YHV1), chronic kidney disease (CKD) patients (CKDP), and healthy controls (HCO). PCASL inversion efficiency was evaluated through numeric simulations considering the measured pulsatile flow velocity profiles and off‐resonance effects for a wide range of gradient parameters, and the results were assessed in vivo. The most robust PCASL implementation was used to measure renal blood flow (RBF) in CKDP and HCO.

Results

Aortic blood velocities reached peak values of 120 cm/s in YHV1, whereas for elderly subjects values were lower by approximately a factor of 2. Simulations and experiments showed that by reducing the gradient average (Gave) and the selective to average gradient ratio (Gmax/Gave), labeling efficiency was maximized and PCASL robustness to off‐resonance was improved. The study in CKDP and HCO showed significant differences in RBF between groups.

Conclusion

An efficient and robust PCASL scheme for renal applications requires a Gmax/Gave ratio of 6‐7 and a Gave value that depends on the aortic blood flow velocities (0.5 mT/m being appropriate for CKDP and HCO).
Optimal output feedback control for discrete‐time Markov jump linear system with input delay and packet losses
Authors: Liu Yue , Han Chunyan , Wang Xiaohong , Wang Wei
Published: October 2020

This article investigates the optimal output feedback control problem for discrete‐time Markov jump linear system (MJLS) with input delay and packet losses in finite horizon. There are three main contributions. First, we assume that the state variable and the jump variable are available to the controller, and then we propose a new version of stochastic maximum principle. Based on the new proposed tool, an optimal state feedback controller is obtained by solving a set of delayed coupled difference Riccati equations. Second, under the condition that the state variable is unavailable to the controller, it is desired to design a dynamic Markovian jump controller such that the closed‐loop system minimizes the performance index. Thus, an optimal Markovian jump linear filter is proposed for MJLS with input delay and packet losses. Finally, based on the optimal filter, we prove that the separation principle holds for this case and then an optimal output feedback controller is presented. Some numerical examples are presented to illustrate the proposed approach.
Safety and Preliminary Efficacy of Ramucirumab in Combination with FOLFOX4 in Patients with Advanced Hepatocellular Carcinoma: A Nonrandomized, Open-Label, Phase Ib Study
Authors: Lin Chia-Chi , Yang Tsai-Sheng , Yen Chia-Jui , Cheng Rebecca , Liu Junjun , Hsu Chiun
Published: October 2020

Lessons Learned

The combination of ramucirumab (8 mg/kg intravenous, day 1 every 2 weeks) and FOLFOX4 as first-line treatment in patients with advanced hepatocellular carcinoma (HCC) was not sufficiently tolerated. Preliminary efficacy data suggest that the combination may provide clinical benefit to patients with HCC. Dose modification and patient selection should be considered for the future development of ramucirumab plus FOLFOX chemotherapy for advanced HCC.

Background

The objective of this study was to investigate the safety, preliminary efficacy, pharmacokinetics, and immunogenicity of ramucirumab plus FOLFOX4 as first-line treatment in patients with advanced hepatocellular carcinoma (HCC).

Methods

Patients received ramucirumab (8 mg/kg) intravenously (IV) on day 1, followed by FOLFOX4 (oxaliplatin 85 mg/m2 IV on day 1, folinic acid 200 mg/m2 IV, bolus fluorouracil [5-FU] 400 mg/m2, and a continuous infusion of 5-FU 600 mg/m2 over 22 hours, on days 1 and 2) every 2 weeks. The primary endpoint was to assess the safety and tolerability of the combination therapy.

Results

Eight patients (6 men, 2 women) were treated; all eight patients experienced at least one treatment-emergent adverse event (TEAE) of grade ≥3. Dose-limiting toxicities occurred in three patients (37.5%): hepatic hemorrhage (grade 4), blood bilirubin increased (grade 3), and febrile neutropenia (grade 3). Two patients discontinued study because of hepatic hemorrhage (grade 4) and blood bilirubin increase (grade 3). Six deaths occurred due to progressive disease, and no deaths due to TEAEs.

Conclusion

There were no unexpected safety findings with ramucirumab plus FOLFOX4 based on the known safety and toxicity of this regimen. The combination was not sufficiently tolerated in patients with advanced HCC at the specified dose and schedule.
Management information systems and the quality of financial statements in local government
Authors: Yuesti Anik , Adnyana I Made Dwi , Pramesti I Gusti Ayu Asri
Published: October 2020

Accountability and transparency of public institutions at both central and local levels is a phenomena which is a major issue these days. The demand for a form of providing information and on government financial activities and performance to the public is a form of accountability and transparency. This study aims to determine the effect of the adoption of Government Accounting Standards, Utilization of SIMDA, and Obedience to Regulations on the Quality of Financial Statements. The study population is the financial part of each OPD and the Regional Financial Board in the Regional Government Organization of Tabanan Regency with the research sample being the head, head of the field, and Tabanan Regency Regional Financial Board staff. The data analysis method used is multiple linear regression. The results showed that Government Accounting Standards (SAP) had a positive effect on the quality of financial statements. SIMDA has a positive effect on the quality of financial statements, and regulations and regulations have a positive effect on the quality of financial statements.
Evaluation of cardiac function in the recipient twin in successfully treated twin‐to‐twin transfusion syndrome using a novel fetal speckle‐tracking analysis
Authors: Harbison Anna L. , Pruetz Jay D. , Ma Stephen , Sklansky Mark S. , Chmait Ramen H. , DeVore Greggory R.
Published: October 2020

Introduction

This study was designed to evaluate ventricular size, shape, and function in recipient twins following laser therapy for twin‐twin transfusion syndrome (TTTS), using novel speckle‐tracking techniques.

Methods

This retrospective study enrolled patients that underwent fetal laser surgery for TTTS and had fetal echocardiograms (FE) performed pre‐ and post‐operatively (op), with adequate resolution in the 4‐chamber view for analysis, using a speckle‐tracking software, to compute the size, shape, and function of both the right (RV) and left (LV) ventricles. Values were indexed to published normal values. Pre‐ and post‐laser Z‐score values for each of the measurements were compared using the Student's t‐test, with significance defined as P < 0.05.

Results

Fifteen TTTS candidate pregnancies that underwent laser therapy between 2010 and 2017, with adequate pre‐ and post‐op FE, were selected for the analysis. Post‐op FE at 28.5 ± 8.3 days showed a significant decrease in RV base dimension, increased LV base dimension, and improvements in many functional measurements: LV global and free wall strain, LV fractional area change, LV basal‐apical fractional change, and LV and RV 24‐segment fractional shortening (FS) of the basal segments.

Conclusions

Cardiac remodeling, following laser surgery in TTTS recipient twins, was demonstrated in the basal portion of both the RV and LV with improved biventricular function.
Are anticholinergic medications used for overactive bladder associated with new onset depression? A population‐based matched cohort study
Authors: Welk Blayne , McArthur Eric
Published: October 2020

Purpose

Prior research has suggested that anticholinergic medications used for overactive bladder are associated with depression. Our objective was to test this hypothesis by comparing rates of new onset depression among anticholinergic medication users and those who were prescribed an alternative class of overactive bladder medication.

Methods

We used administrative data records from the province of Ontario, Canada and a matched cohort design. We matched patients who were newly prescribed an oral anticholinergic to those prescribed a beta‐3 agonist medication in a 2:1 ratio which included a propensity score that incorportated 75 baseline characteristics. The primary outcome of depression was measured using a validated definition, and the at‐risk period for our outcome of interest was between the initial date the prescription was filled, and up to 3 months after the end of continuous usage of that medication. Hazard ratios (HRs) were estimated using Cox proportional hazards regression.

Results

We matched 23 622 beta‐3 agonist users (mirabegron) to 47 324 anticholinergic users (most commonly tolterodine, oxybutynin, and solifenacin). The rate of depression was similar among beta‐3 agonist users (11.2 per 1000 patient‐years) and anticholinergic users (11.9 per 1000 patient‐years). In our primary analysis, the risk of depression among anticholinergic users was not significantly different compared to beta‐3 agonist users (HR 1.08 [95% CI 0.92‐1.28, P = .35]).

Conclusion

Contrary to a previous report, overactive bladder anticholinergic medications do not appear to be associated with new onset depression.
Toxicity Assessment of Energetic Materials by Using the Luminescent Bacteria Inhibition Test
Authors: Klapötke Thomas M. , Scharf Regina , Stierstorfer Jörg , Unger Cornelia C.
Published: October 2020

The luminescent bacteria inhibition test using Aliivibrio fischeri is a well‐established method to determine the aquatic toxicity of soluble chemicals. More precisely, the effective concentration (EC50) after 15 and 30 min is determined in this test. The inhibition of natural bioluminescence of these bacteria gives a first idea of the toxicity of compounds towards some aquatic organisms. It is a cost and time efficient experimental method, which does not involve animals. In this contribution, the experimental set up, comparability with other measurements, and results of recently described compounds is presented. Different types of energetic materials such as coordination (e. g. [Cu(dtp)3](ClO4)2 and [Fe(MTZ)6](ClO4)2), neutral (e. g. azidoethanol, 1‐ and 2‐aminotetrazole) and ionic (e. g. polynitropyrazolates and PETNC salts) compounds were investigated and compared to commonly used materials, like RDX, ammonium perchlorate (AP) and azide salts. Furthermore, different substitution patterns and energetic functionalities such as azido‐, nitro‐ and nitramino‐groups were investigated.
Semimechanistic Clearance Models of Oncology Biotherapeutics and Impact of Study Design: Cetuximab as a Case Study
Authors: Grisic Ana‐Marija , Khandelwal Akash , Bertolino Mauro , Huisinga Wilhelm , Girard Pascal , Kloft Charlotte
Published: October 2020

This study aimed to explore the currently competing and new semimechanistic clearance models for monoclonal antibodies and the impact of clearance model misspecification on exposure metrics under different study designs exemplified for cetuximab. Six clearance models were investigated under four different study designs (sampling density and single/multiple‐dose levels) using a rich data set from two cetuximab clinical trials (226 patients with metastatic colorectal cancer) and using the nonlinear mixed‐effects modeling approach. A two‐compartment model with parallel Michaelis–Menten and time‐decreasing linear clearance adequately described the data, the latter being related to post‐treatment response. With respect to bias in exposure metrics, the simplified time‐varying linear clearance (CL) model was the best alternative. Time‐variance of the linear CL component should be considered for biotherapeutics if response impacts pharmacokinetics. Rich sampling at steady‐state was crucial for unbiased estimation of Michaelis–Menten elimination in case of the reference (parallel Michaelis–Menten and time‐varying linear CL) model.
Nitrogen‐doped mesoporous carbon materials for oxidative dehydrogenation of propane
Authors: Zhang Wunengerile , Zhao Gegerile , Muschin Tegshi , Bao Agula
Published: October 2020

The CN‐15‐x series materials with different doses of SBA‐15 template and the CN‐y‐2.0 series materials with different hard templates were prepared by the hard template method with hexamethylenetetramine as the carbon and nitrogen source. The obtained mesoporous carbon materials were characterized by X‐ray diffraction (XRD), N2 adsorption–desorption, transmission electron microscopy (TEM), Raman spectroscopy, and X‐ray photoelectron spectroscopy (XPS). The catalytic performance of propane oxidative dehydrogenation was determined. The characterization results indicate that the catalytic activity of CN‐15‐2.0 with a bipartite hexagonal ordered structure was higher than those of the other materials. The conversion of propane was 22.98%, and the selectivity toward propylene was 41.70%.
Anchoring Positively Charged Pd Single Atoms in Ordered Porous Ceria to Boost Catalytic Activity and Stability in Suzuki Coupling Reactions
Authors: Tao Xueqin , Long Ran , Wu Di , Hu Yangguang , Qiu Ganhua , Qi Zeming , Li Benxia , Jiang Ruibin , Xiong Yujie
Published: October 2020

Single‐atom (SA) catalysis bridging homogeneous and heterogeneous catalysis offers new opportunities for organic synthesis, but developing SA catalysts with high activity and stability is still a great challenge. Herein, a heterogeneous catalyst of Pd SAs anchored in 3D ordered macroporous ceria (Pd‐SAs/3DOM‐CeO2) is developed through a facile template‐assisted pyrolysis method. The high specific surface area of 3DOM CeO2 facilitates the heavily anchoring of Pd SAs, while the introduction of Pd atoms induces the generation of surface oxygen vacancies and prevents the grain growth of CeO2 support. The Pd‐SAs/3DOM‐CeO2 catalyst exhibits excellent activity toward Suzuki coupling reactions for a broad scope of substrates under ambient conditions, and the Pd SAs can be stabilized in CeO2 in long‐term catalytic cycles without leaching or aggregating. Theoretical calculations indicate that the CeO2 supported Pd SAs can remarkably reduce the energy barriers of both transmetalation and reductive elimination steps for Suzuki coupling reactions. The strong metal‐support interaction contributes to modulating the electronic state and maintaining the stability of Pd SA sites. This work demonstrates an effective strategy to design and synthesize stable single‐atom catalysts as well as sheds new light on the origin for enhanced catalysis based on the strong metal‐support interactions.
Engineering the Low Coordinated Pt Single Atom to Achieve the Superior Electrocatalytic Performance toward Oxygen Reduction
Authors: Song Zhongxin , Zhu Ya‐Nan , Liu Hanshuo , Banis Mohammad Norouzi , Zhang Lei , Li Junjie , Doyle‐Davis Kieran , Li Ruying , Sham Tsun‐Kong , Yang Lijun , Young Alan , Botton Gianluigi A. , Liu Li‐Min , Sun Xueliang
Published: October 2020

Configuring metal single‐atom catalysts (SACs) with high electrocatalytic activity and stability is one efficient strategy in achieving the cost‐competitive catalyst for fuel cells’ applications. Herein, the atomic layer deposition (ALD) strategy for synthesis of Pt SACs on the metal–organic framework (MOF)‐derived N‐doped carbon (NC) is proposed. Through adjusting the ALD exposure time of the Pt precursor, the size‐controlled Pt catalysts, from Pt single atoms to subclusters and nanoparticles, are prepared on MOF‐NC support. X‐ray absorption fine structure spectra determine the increased electron vacancy in Pt SACs and indicate the Pt–N coordination in the as‐prepared Pt SACs. Benefiting from the low‐coordination environment and anchoring interaction between Pt atoms and nitrogen‐doping sites from MOF‐NC support, the Pt SACs deliver an enhanced activity and stability with 6.5 times higher mass activity than that of Pt nanoparticle catalysts in boosting the oxygen reduction reaction (ORR). Density functional theory calculations indicate that Pt single atoms prefer to be anchored by the pyridinic N‐doped carbon sites. Importantly, it is revealed that the electronic structure of Pt SAs can be adjusted by adsorption of hydroxyl and oxygen, which greatly lowers free energy change for the rate‐determining step and enhances the activity of Pt SACs toward the ORR.
The Dynamics of an Oscillating Enzymatic Reaction Network is Crucially Determined by Side Reactions
Authors: Pogodaev Aleksandr A. , Lap Tijs T. , Huck Wilhelm T. S.
Published: October 2020

Synthetic complex chemical systems are often subject to perturbations in reaction conditions. To ensure robust functioning of these systems in real‐world applications, a better understanding is required of how resilience to perturbations could be included in the design of these systems. In order to develop such an understanding we need a deeper insight into how chemical systems respond to perturbations. Here, we study the effect of spiking concentrations in an oscillating enzymatic reaction network. We identify that a different magnitude of a perturbation triggers two distinctive responses: obtaining sustained oscillations and causing the loss of the amplitude. We rationalise our findings based on non‐linear dynamics and identify that non‐essential side reactions crucially tailor the observed behaviour.
Decolonizing Beginning Literacy Instruction: Views From Ugandan Teachers
Authors: Beach Sara Ann (Sally) , Nyirumbe Sr. Rosemary , Monk David , Pia Okecha Sr. Esther
Published: October 2020

The International Literacy Association is a global advocacy organization, and literacy is viewed as a human right worldwide. This department highlights research and research‐to‐practice at the international level to bring global best teaching practices to the forefront. Topics may include best practices for literacy instruction in Europe or other continents/countries, partnership and collaborative projects between international schools/teachers, and advocacy.
Exposing the myths of household water insecurity in the global north: A critical review
Authors: Meehan Katie , Jepson Wendy , Harris Leila M. , Wutich Amber , Beresford Melissa , Fencl Amanda , London Jonathan , Pierce Gregory , Radonic Lucero , Wells Christian , Wilson Nicole J. , Adams Ellis Adjei , Arsenault Rachel , Brewis Alexandra , Harrington Victoria , Lambrinidou Yanna , McGregor Deborah , Patrick Robert , Pauli Benjamin , Pearson Amber L. , Shah Sameer , Splichalova Dacotah , Workman Cassandra , Young Sera
Published: October 2020

Safe and secure water is a cornerstone of modern life in the global North. This article critically examines a set of prevalent myths about household water in high‐income countries, with a focus on Canada and the United States. Taking a relational approach, we argue that household water insecurity is a product of institutionalized structures and power, manifests unevenly through space and time, and is reproduced in places we tend to assume are the most water‐secure in the world. We first briefly introduce “modern water” and the modern infrastructural ideal, a highly influential set of ideas that have shaped household water provision and infrastructure development over the past two centuries. Against this backdrop, we consolidate evidence to disrupt a set of narratives about water in high‐income countries: the notion that water access is universal, clean, affordable, trustworthy, and uniformly or equitably governed. We identify five thematic areas of future research to delineate an agenda for advancing scholarship and action—including challenges of legal and regulatory regimes, the housing‐water nexus, water affordability, and water quality and contamination. Data gaps underpin the experiences of household water insecurity. Taken together, our review of water security for households in high‐income countries provides a conceptual map to direct critical research in this area for the coming years.

This article is categorized under:

Human Water > Human Water
Analysis of time‐fractional fuzzy vibration equation of large membranes using double parametric based Residual power series method
Authors: Jena Rajarama Mohan , Chakraverty Snehashish , Jena Subrat Kumar , Sedighi Hamid M.
Published: October 2020

The study of the time‐fractional vibration equation (VE) of large membranes is vital due to its widespread applications. Various researchers have investigated the titled problem in which the variables and parameters have been considered as crisp/exact. However, in actual practice, this may contain uncertainty because of errors in observations, maintenance induced error, and other errors. In this investigation, we have considered these uncertainties as interval/fuzzy, and a method, namely double parametric form of fuzzy numbers are used to solve the uncertain fractional vibration model of order . The titled problem has been solved under various cases using the Residual power series method (RPSM). The performance of the present method is well in terms of computational efficiency. The consistency of the method is displayed by providing numerical solutions for various cases. Obtained results are depicted in terms of figures and are also compared with individual cases.
Adaptation to Climate Change: Opportunities and Challenges from Zambia
Authors: Rawlins Jonty , Kalaba Felix Kanungwe
Published: October 2020

Context appropriate adaptation interventions and strategies that respond directly to localized climate change stressors, hazards, and vulnerabilities are critical for the sustainable development of countries like Zambia. This chapter examines both localized and systemic climate change risk pathways and barriers to adaptation action in Zambia.

A three-staged methodology was applied, combining content analysis, focus group discussions, and expert interviews. Livelihood diversification was identified as the central adaptation option across Zambia, despite little empirical research detailing possible risks of diversification. The dominant adaptation discourse is focused specifically on diversifying within agriculture-based livelihoods. However, as all agricultural activities are impacted by climate change, diversification also needs to be explored in value-added or alternative sectors. With this, a weak policy framework and enabling environment are exacerbating cycles of poverty that underpin climate change vulnerability in Zambia. Moreover, maladaptation risks of existing diversification interventions are high as generic approaches often do not provide suitable options to complex and localized risk profiles.

To implement a sustainable transition toward climate resilient and compatible development in Zambia, the authors recommend that a systematic livelihood diversification strategy should be rolled out and future research programs designed to support this. Specifically, this necessitates a system-wide analysis of pre-identified livelihood diversification pathways that can be adapted to different scenarios given the current and future climate uncertainties at local scales. The approach should focus on harnessing the positive feedback loops for systematic change to build resilience, while minimizing the dominant risk pathways and eliminating persistent barriers that enable positive feedback loops driving vulnerability to climate change. Thorough stakeholder engagement and incremental development of diversification options, incentives, penalties, and other governance and/or policy mechanisms will be needed to support these processes.
A brief history of how microscopic studies led to the elucidation of the 3D architecture and macromolecular organization of higher plant thylakoids
Authors: Staehelin L. Andrew , Paolillo Dominick J.
Published: October 2020

Microscopic studies of chloroplasts can be traced back to the year 1678 when Antonie van Leeuwenhoek reported to the Royal Society in London that he saw green globules in grass leaf cells with his single-lens microscope. Since then, microscopic studies have continued to contribute critical insights into the complex architecture of chloroplast membranes and how their structure relates to function. This review is organized into three chronological sections: During the classic light microscope period (1678–1940), the development of improved microscopes led to the identification of green grana, a colorless stroma, and a membrane envelope. More recent (1990–2020) chloroplast dynamic studies have benefited from laser confocal and 3D-structured illumination microscopy. The development of the transmission electron microscope (1940–2000) and thin sectioning techniques demonstrated that grana consist of stacks of closely appressed grana thylakoids interconnected by non-appressed stroma thylakoids. When the stroma thylakoids were shown to spiral around the grana stacks as multiple right-handed helices, it was confirmed that the membranes of a chloroplast are all interconnected. Freeze-fracture and freeze-etch methods verified the helical nature of the stroma thylakoids, while also providing precise information on how the electron transport chain and ATP synthase complexes are non-randomly distributed between grana and stroma membrane regions. The last section (2000–2020) focuses on the most recent discoveries made possible by atomic force microscopy of hydrated membranes, and electron tomography and cryo-electron tomography of cryofixed thylakoids. These investigations have provided novel insights into thylakoid architecture and plastoglobules (summarized in a new thylakoid model), while also producing molecular-scale views of grana and stroma thylakoids in which individual functional complexes can be identified.
Conditional Deletion of Foxg1 Alleviates Demyelination and Facilitates Remyelination via the Wnt Signaling Pathway in Cuprizone-Induced Demyelinated Mice
Authors: Dong Fuxing , Liu Dajin , Jiang Feiyu , Liu Yaping , Wu Xiuxiang , Qu Xuebin , Liu Jing , Chen Yan , Fan Hongbin , Yao Ruiqin
Published: October 2020

The massive loss of oligodendrocytes caused by various pathological factors is a basic feature of many demyelinating diseases of the central nervous system (CNS). Based on a variety of studies, it is now well established that impairment of oligodendrocyte precursor cells (OPCs) to differentiate and remyelinate axons is a vital event in the failed treatment of demyelinating diseases. Recent evidence suggests thatFoxg1is essential for the proliferation of certain precursors and inhibits premature neurogenesis during brain development. To date, very little attention has been paid to the role ofFoxg1in the proliferation and differentiation of OPCs in demyelinating diseases of the CNS. Here, for the first time, we examined the effects ofFoxg1on demyelination and remyelination in the brain using a cuprizone (CPZ)-induced mouse model. In this work, 7-week-oldFoxg1conditional knockout and wild-type (WT) mice were fed a diet containing 0.2% CPZ w/w for 5 weeks, after which CPZ was withdrawn to enable remyelination. Our results demonstrated that, compared with WT mice,Foxg1-knockout mice exhibited not only alleviated demyelination but also accelerated remyelination of the demyelinated corpus callosum. Furthermore, we found thatFoxg1knockout decreased the proliferation of OPCs and accelerated their differentiation into mature oligodendrocytes bothin vivoandin vitro. Wnt signaling plays a critical role in development and in a variety of diseases. GSK-3β, a key regulatory kinase in the Wnt pathway, regulates the ability of β-catenin to enter nuclei, where it activates the expression of Wnt target genes. We then used SB216763, a selective inhibitor of GSK-3β activity, to further demonstrate the regulatory mechanism by whichFoxg1affects OPCsin vitro. The results showed that SB216763 clearly inhibited the expression of GSK-3β, which abolished the effect of the proliferation and differentiation of OPCs caused by the knockdown ofFoxg1. These results suggest thatFoxg1is involved in the proliferation and differentiation of OPCs through the Wnt signaling pathway. The present experimental results are some of the first to suggest thatFoxg1is a new therapeutic target for the treatment of demyelinating diseases of the CNS.
Optimal gradient estimates for the perfect conductivity problem with C1,α inclusions
Authors: Xu Longjuan , Chen Yu , Li Haigang
Published: October 2020

In high-contrast composite materials, the electric field concentration is a common phenomenon when two inclusions are close to touch. It is important from an engineering point of view to study the dependence of the electric field on the distance between two adjacent inclusions. In this paper, we derive upper and lower bounds of the gradient of solutions to the conductivity problem where two perfectly conducting inclusions are located very close to each other. To be specific, we extend the known results of Bao-Li-Yin (ARMA 2009) in two folds: First, we weaken the smoothness of the inclusions from

C^{2,\alpha }

to

C^{1,\alpha }

. To obtain a pointwise upper bound of the gradient, we follow an iteration technique which is first used to deal with elliptic systems in a narrow domain by Li-Li-Bao-Yin (QAM 2014). However, when the inclusions are of

C^{1,\alpha }

, we can not use

W^{2,p}

estimates for elliptic equations any more. In order to overcome this new difficulty, we take advantage of De Giorgi-Nash estimates and Campanato's approach to apply an adapted version of the iteration technique with respect to the energy. A lower bound in the shortest line between two inclusions is also obtained to show the optimality of the blow-up rate. Second, when two inclusions are only convex but not strictly convex, we prove that blow-up does not occur any more. The establishment of the relationship between the blow-up rate of the gradient and the order of the convexity of the inclusions reveals the mechanism of such concentration phenomenon.
World War II and Southeast Asia
Authors: Huff Gregg
Published: October 2020

From December 1941, Japan, as part of its plan to build an East Asian empire and secure oil supplies essential for war in the Pacific, swiftly took control of Southeast Asia. Japanese occupation had a devastating economic impact on the region. Japan imposed country and later regional autarky on Southeast Asia, dictated that the region finance its own occupation, and sent almost no consumer goods. GDP fell by half everywhere in Southeast Asia except Thailand. Famine and forced labour accounted for most of the 4.4 million Southeast Asian civilian deaths under Japanese occupation. In this ground-breaking new study, Gregg Huff provides the first comprehensive account of the economies and societies of Southeast Asia during the 1941-1945 Japanese occupation. Drawing on materials from 25 archives over three continents, his economic, social and historical analysis presents a new understanding of Southeast Asian history and development before, during and after the Pacific War.
Willa Cather
Authors: Squire Kelsey
Published: October 2020

A contextualizing overview of the polarized critical reception of Willa Cather, one of the pre-eminent US authors of the twentieth-century.
DECIDABILITY OF ADMISSIBILITY: ON A PROBLEM BY FRIEDMAN AND ITS SOLUTION BY RYBAKOV
Authors: GOUDSMIT JEROEN P.
Published: October 2020

Rybakov (1984a) proved that the admissible rules of$\mathsf {IPC}$are decidable. We give a proof of the same theorem, using the same core idea, but couched in the many notions that have been developed in the mean time. In particular, we illustrate how the argument can be interpreted as using refinements of the notions of exactness and extendibility.