bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcomes of Adenotonsillectomy for Obstructive Sleep Apnea in Prader‐Willi Syndrome: Systematic Review and Meta‐analysis
Authors: Clements Anna Christina , Dai Xi , Walsh Jonathan M. , Sterni Laura M. , Prichett Laura , Boss Emily F. , Seal Stella M. , Ryan Marisa A.
Published: July 2020

Objectives

Prader‐Willi syndrome (PWS) increases the risk of obstructive sleep apnea (OSA) due to obesity, hypotonia, and abnormal ventilatory responses. We evaluated post‐adenotonsillectomy complications, polysomnography changes, and quality of life in children with OSA and PWS.

Study Design

Systematic review and meta‐analysis.

Methods

We conducted a systematic review and meta‐analysis by searching PubMed, Embase, Cochrane, Web of Science, and Scopus. Two researchers independently reviewed studies about adenotonsillectomy for OSA in patients <21 years with PWS. We extracted study design, patient numbers, age, complications, polysomnography, and quality of life. We pooled postoperative changes in apnea hypopnea index (AHI) for meta‐analysis. We applied Methodological Index for Nonrandomized Studies (MINORS) criteria to assess study quality.

Results

The initial search yielded 169 studies. We included 68 patients from eight studies with moderate to high risk of bias. Six studies reported on complications and 12 of 51 patients (24%) had at least one. Velopharyngeal insufficiency was the most commonly reported complication (7/51, 14%). We included seven studies in meta‐analysis. Mean postoperative improvement in AHI was 7.7 (95% CI: 4.9–10.5). Postoperatively 20% (95% CI: 3%–43%) had resolution of OSA with AHI < 1.5 while 67% (95% CI: 50%–82%) had improvement from severe/moderate OSA to mild/resolved (AHI < 5). Two studies evaluated quality of life and demonstrated improvement.

Conclusions

Children with PWS undergoing adenotonsillectomy for OSA have a substantial risk of postoperative complications that may require additional interventions, especially velopharyngeal insufficiency. Despite improvements in polysomnography and quality of life, many patients had residual OSA. This information can be used to counsel families when considering OSA treatment options. Laryngoscope, 131:898–906, 2021
Nitrogen rhizodeposition by legumes and its fate in agroecosystems: A field study and literature review
Authors: Wang Xiquan , Yang Yadong , Pei Kuan , Zhou Jie , Peixoto Leanne , Gunina Anna , Zeng Zhaohai , Zang Huadong , Rasmussen Jim , Kuzyakov Yakov
Published: July 2020

Quantification of legume nitrogen (N) rhizodeposition (N derived from roots) and its fate in agroecosystems is crucial for managing soil fertility, land productivity, and agriculture sustainability. In contrast to forage legumes, the N rhizodeposition by grain legumes is nearly unknown. Therefore, N rhizodeposition of four grain legumes and its transfer to subsequent wheat crops was quantified using the 15N stem labeling method under field conditions. The N rhizodeposition of the grain legumes: peanut, soybean, mungbean, and adzuki bean amounted to 25, 51, 20, and 63 kg N ha−1, respectively. N rhizodeposition was not affected by fertilization, and it was 53–257% more accumulated in topsoil (0–20 cm) than that in subsoil (20–40 cm). However, N rhizodeposition per unit of root biomass in subsoil was 3.5‐times as much as that in topsoil (p < 0.05), indicating the importance of legumes for soil fertility and exploration in subsoil. Remarkably, subsequent wheat utilized 13–85% of legume N rhizodeposition, which contributed to 4–20% of total wheat N uptake. Combining the present data with the literature review, the average N rhizodeposition of legumes (both grain and forage legumes) is 83 kg N ha−1 (n = 75), and one‐fourth of which was utilized by subsequent cereals. Increasing root biomass by 1 g increases rhizodeposition by 53 mg N. In conclusion, legume N rhizodeposition is crucial for the sustainability of legume‐based crop rotations resulting in soil N build‐up and is an important N source for subsequent crops.
Characterization of volatile compounds in Swedish yellow and gray peas: Implications for new legume‐based ingredients
Authors: Ferawati Ferawati , Witthöft Cornelia , Bergström Maria
Published: July 2020

There is a growing demand for alternative protein‐source ingredients from domestically cultivated pulses in Europe, including Sweden. However, the use of legumes as a food ingredient is limited by the presence of a distinct beany flavor. Mapping the volatile compounds composition in a standardized approach will aid in comparing different legume varieties and processing treatments. The composition of volatile compounds in flour from yellow and gray peas (raw and boiled) was investigated and compared. Volatile compounds were isolated by headspace solid‐phase microextraction (HS‐SPME) and analyzed using gas chromatography‐mass spectrophotometry (GC‐MS). A total of 43 volatiles were identified, consisting mostly of aldehydes, followed by alkanes, alcohols, ketones, alkenes, furans, terpenes, aromatics, and sulfur‐containing compounds. Boiling led to a marked reduction in alcohols and an increase in aldehydes. Several markers of beany flavor, such as 1‐octen‐3‐ol, 2‐pentylfuran, and 3,5‐octadien‐2‐one, were significantly decreased after boiling. The composition of volatiles collected from yellow and gray peas was comparable, but boiled yellow pea had a higher abundance of beany flavor as compared to gray pea. Gray pea is an interesting variety to be explored further as a potential alternative to the well‐known yellow pea.
Metabolism overrides photo‐oxidation in CO2 dynamics of Arctic permafrost streams
Authors: Rocher‐Ros Gerard , Harms Tamara K. , Sponseller Ryan A. , Väisänen Maria , Mörth Carl‐Magnus , Giesler Reiner
Published: July 2020

Global warming is enhancing the mobilization of organic carbon (C) from Arctic soils into streams, where it can be mineralized to CO2 and released to the atmosphere. Abiotic photo‐oxidation might drive C mineralization, but this process has not been quantitatively integrated with biological processes that also influence CO2 dynamics in aquatic ecosystems. We measured CO2 concentrations and the isotopic composition of dissolved inorganic C (δ13CDIC) at diel resolution in two Arctic streams, and coupled this with whole‐system metabolism estimates to assess the effect of biotic and abiotic processes on stream C dynamics. CO2 concentrations consistently decreased from night to day, a pattern counter to the hypothesis that photo‐oxidation is the dominant source of CO2. Instead, the observed decrease in CO2 during daytime was explained by photosynthetic rates, which were strongly correlated with diurnal changes in δ13CDIC values. However, on days when modeled photosynthetic rates were near zero, there was still a significant diel change in δ13CDIC values, suggesting that metabolic estimates are partly masked by O2 consumption from photo‐oxidation. Our results suggest that 6–12 mmol CO2‐C m−2 d−1 may be generated from photo‐oxidation, a range that corresponds well to previous laboratory measurements. Moreover, ecosystem respiration rates were 10 times greater than published photo‐oxidation rates for these Arctic streams, and accounted for 33–80% of total CO2 evasion. Our results suggest that metabolic activity is the dominant process for CO2 production in Arctic streams. Thus, future aquatic CO2 emissions may depend on how biotic processes respond to the ongoing environmental change.
Paroxysmal dyskinesia and epilepsy in pseudohypoparathyroidism
Authors: Zhang Chao , Zhou Xiangqin , Feng Mei , Yue Wei
Published: July 2020

Background

Paroxysmal kinesigenic dyskinesia (PKD) and epilepsy share common pathogenic mechanisms but their pathophysiological connections remain unknown. Our study reports an individual with both disorders as a consequence of pseudohypoparathyroidism (PHP). This observation suggests potential shared pathophysiological mechanisms between PKD and epilepsy.

Methods

We report the case of a 15‐year‐old male with pre‐diagnosed PKD and symptomatic epilepsy. We recorded the symptoms and carried out comprehensive biochemical, genetic, imaging, and EEG analyses to examine the characteristics and potentially shared etiology of these conditions.

Results

In this case, the patient's PKD and symptomatic epilepsy were secondary to pseudohypoparathyroidism (PHP). The patient had a seven‐year history of intermittent, involuntary paroxysmal episodic movements, and a six‐year history of a loss of consciousness with convulsions. The electroencephalography results showed that the paroxysmal low and medium amplitude slow waves, isolated sharp waves, and sharp slow‐wave release occurred in the right prefrontal temporal cortex. Serum analysis indicated a calcium concentration of 1.91 mmol/L, a phosphorus concentration of 2.68 mmol/L, an alkaline phosphatase concentration of 114 IU/L, and a parathyroid hormone concentration of 109 pg/ml. Computerized tomography and magnetic resonance imaging results showed multiple calcifications in the bilateral frontal and parietal lobe cortex, bilateral thalamus, basal ganglia, and centrum semiovale. Furthermore, GNAS methylation abnormalities were discovered during methylation testing. There was no recurrence of abnormal movements or epileptic seizures, and calcium concentrations returned to healthy levels, following the pharmacological treatment of PHP.

Conclusion

In this case, PKD and symptomatic epilepsy were caused by PHP. This report underscores the importance of looking for biochemical abnormalities in PKD and symptomatic epilepsy patients. We suggest that all such intractable epilepsy seizure patients should be screened for PHP.
Abdominal wall reconstruction using anterolateral thigh flap with microsurgical pedicle lengthening technique: A case report
Authors: Kim Suhwan , Lee Kyeong‐Tae
Published: July 2020

Pedicled anterolateral thigh (ALT) flap has been employed for coverage of low abdominal wall defects. However, its use is limited for defects located more on the cranial side because of insufficient pedicle length. We present a case of successful reconstruction of mid‐abdominal wall defect using pedicled ALT flap, overcoming the issue of pedicle length shortage with a microsurgical pedicle lengthening technique. A 75‐year‐old man suffered from a 12 × 8 cm full‐thickness soft tissue defect on his mid‐abdominal wall originated from colon anastomosis site leakage after ileostomy takedown surgery. A pedicled ALT flap was planned for the defect coverage. After we performed debridement to prepare the wound bed, a 14 × 8.5 cm sized ALT flap based on two lateral circumflex femoral artery (LCFA) perforators was elevated. During intramuscular dissection of perforators, we dissected the distal portion of the LCFA descending branch. After full dissection of the pedicle to source vessels, we attempted to transfer the flap, but still the flap had short pedicle. We transected the pedicle just distal to the bifurcating point and reconnected it to the distal end of the dissected descending LCFA branch with microsurgical anastomosis. We passed the flap through a subcutaneous tunnel and conducted smooth flap insetting without any tension on the lengthened pedicle. Postoperatively, the wound healed successfully without complications. The patient was discharged 2 weeks after surgery and followed up at postoperative 3 months without adverse events. A local ALT flap with pedicle lengthened might be a reliable option for reconstruction of supraumbilical abdominal defects.
Effects of nonlocal thermoelasticity on nanoscale beams based on couple stress theory
Authors: Abouelregal Ahmed E. , Mohammed Wael W.
Published: July 2020

A modified nonlocal Bernoulli–Euler model was established in this paper to analyze thermoelastic interactions in isotropic nanobeams subjected to ramp‐type heating, depending on the modified couple stress and generalized thermoelasticity theories. To solve this problem, the thermoelasticity theory with one thermal relaxation time (Lord–Shulman [LS]) is proposed. Due to the modified couple stress, the analytical expressions for deflection, temperature, flexure moment, and displacement in the nanobeam were obtained by using the Laplace transform technique. In addition, comparisons were shown in graphs to estimate the effects of the various parameters such as the couple stress, and the ramping time parameter on all the fields studied under consideration. Also, the numerical results are provided to demonstrate the small‐scale impact on the resonator of the nanobeams.
Applying a repetitive time‐reversal method to reduce input power of a wearable hyperthermia applicator for breast cancer treatment
Authors: Rahimi Faezeh , Chamaani Somayyeh
Published: July 2020

In this article, a hyperthermia healing system is presented for cancer treatment. To alleviate most of the microwave hyperthermia systems problems, such as high input power, complicated beamforming method, unwanted hot spots for superficial tumors, and bulky profile, a simple repetitive time‐reversal method is proposed to design a low power wearable hyperthermia applicator with low hotspots at 915 MHz. The objective of this algorithm is to obtin the desired focusing by the minimum possible number of antennas in an appropriate time and minimum required input power. In this paper, first, a symmetric 11‐element patch array is considered. Then, by applying a repetitive time‐reversal method, the number of elements decreases to 7 for deep and 4 for both superficial and intermediate tumors, respectively. The steady‐state temperature/specific absorption rate focusing and transient thermal analysis are investigated in CST MWS and COMSOL, respectively. The target temperature of 43°C is met after less than 10 minutes. The focusing diameter size varies between 1 and 2 cm depending on the number of elements and arrangements considered for different tumors. Compared to literature, this applicator needs very low input power, produces less unwanted hotspots, improves pationt comfort, reduces treatment cost which all leads to patient treatment persistency. Moreover, it does not need any complicated beamforming method.
Blood–brain barrier permeability measurement by biexponentially modeling whole‐brain arterial spin labeling data with multiple T2‐weightings
Authors: Schidlowski Martin , Boland Markus , Rüber Theodor , Stöcker Tony
Published: July 2020

Blood–brain barrier (BBB) permeability assessment remains of ongoing interest in clinical practice and research. Transitions between intravascular (IV) and extravascular (EV) gray matter (GM) compartments may provide information regarding the microstructural status of the BBB. Due to different transverse relaxation times (T2) of water protons in vessels and GM, it is possible to determine the compartment in which these protons are located. This work presents and investigates the feasibility of a simplified analytical approach for compartmentalizing the proportions of magnetically marked water protons into IV and EV GM components by biexponentially modeling T2‐weighted arterial spin labeling (ASL) data. Numerous model assumptions were used to stabilize the fit and achieve in vivo applicability. Particularly, transverse relaxation times of IV and EV water protons were determined from the analysis of two supporting T2‐weighted ASL measurements, utilizing a monoexponential signal model. This stabilized a two‐parameter biexponential fit of ASL data with T2 preparation (PLD = 0.9/1.2/1.5/1.8 s, TET2Prep = 0/30/40/60/80/120/160 ms), which thereby robustly provided estimates of the IV and EV compartment fractions. Experiments were conducted with three healthy volunteers in a 3 T scanner. Averaged over all subjects, the labeled water protons inherit T2,IV = 200 ± 18 ms initially and adapt T2,EV = 91 ± 2 ms with a longer retention time in cerebral structures. Accordingly, the EVlocated ASL signal fraction rises with increasing PLD from 0.31 ± 0.11 at the shortest PLD of 0.9 s to 0.73 ± 0.02 at the longest PLD of 1.8s. These results indicate a transition of the water protons from IV to EV space. The findings support the potential of biexponential modeling for compartmentalizing ASL spin fractions between IV and EV space. The novel integration of monoexponential parameter estimates stabilizes the two‐compartment model fit, suggesting that this technique is suitable for robustly estimating the BBB permeability in vivo.
Phase‐field modeling of brittle fracture in a 3D polycrystalline material via an adaptive isogeometric‐meshfreeapproach
Authors: Li Weidong , Nguyen‐Thanh Nhon , Zhou Kun
Published: July 2020

Phase‐field modeling, which introduces the regularized representation of sharp crack topologies, provides a convenient strategy for tackling 3D fracture problems. In this work, an adaptive isogeometric‐meshfree approach is developed for the phase‐field modeling of brittle fracture in a 3D polycrystalline material. The isogeometric‐meshfree approach uses moving least‐squares approximations to construct the equivalence between isogeometric basis functions and meshfree shape functions, thus inheriting the flexible local mesh refinement scheme from a meshfree method. This refinement scheme is improved by introducing an error estimator that includes both the phase field and its gradient. With the present approach, numerical implementations of the adaptive phase‐field modeling that introduces the anisotropy of fracture resistance in polycrystals are proposed. In this way, propagating cracks can be dynamically tracked, and the mesh near cracks is refined in a meshfree manner without requiring a priori knowledge of crack paths. Furthermore, the intergranular and transgranular crack propagation patterns in polycrystalline materials can be simulated by the present approach. A series of numerical examples that deal with the isotropic and anisotropic fracture are investigated to demonstrate the robustness and effectiveness of the proposed approach.
Factors influencing the utilization of Focused antenatal care services during pregnancy, a study among postnatal women in a tertiary healthcare facility, Ghana
Authors: Konlan Kennedy Diema , Saah Joel Afram , Amoah Roberta Mensima , Doat Abdul Razak , Mohammed Iddrisu , Abdulai Juliana Asibi , Konlan Kennedy Dodam
Published: July 2020

Aim

To assess the factors that influence the utilization of FANC services among pregnant women.

Methodology

A cross‐sectional quantitative study conducted among 210 postnatal women in Ho Teaching Hospital. Data were entered into Microsoft excel, cleaned and transported to SPSS and analysed. Cross tabulations were used to explore associations between variables.

Results

The respondents indicated that FANC would enable them to receive comprehensive ANC (74.8%). Higher parity was significantly associated with low utilization of FANC (p = .028). Long distance to the health facility, seeking permission to use FANC was significantly associated with low utilization of FANC (p < .001). Fear associated with witchcraft was associated with low FANC utilization (p < .001).
Obesity May Connect Insulin Resistance to Decreased Neuronal Viability in Human Diabetic Brain
Authors: Lee Suji , Joo Yoon Ji , Kim Rye Young , Hwang Jaeuk , Lim Soo Mee , Yoon Sujung , Kim Jungyoon
Published: July 2020

Objective

This study aimed to investigate the relationship between insulin resistance and markers of neuronal viability and energy metabolism, as well as the additive effects of overweight or obesity, in individuals with type 2 diabetes mellitus (T2DM).

Methods

Using 1H‐magnetic resonance spectroscopy, prefrontal N‐acetyl aspartate (NAA) and creatine levels, markers for neuronal viability and energy metabolism, respectively, were measured in 50 adults with overweight or obesity and T2DM (T2DM‐O; aged 49.0 ± 7.4 years; 50% female), 50 adults with normal weight and T2DM (T2DM‐N), and 50 healthy adults with normal weight (healthy‐control [HC] group) matched for age and sex. The homeostatic model assessment for insulin resistance levels were calculated to assess insulin resistance.

Results

Prefrontal NAA levels were lower in the T2DM‐O group relative to the HC group (t = −2.51, P = 0.013). Higher insulin resistance was associated with lower prefrontal NAA levels in the T2DM‐O group (t = −2.21, P = 0.032) but not in the T2DM‐N group (t = −0.72, P = 0.48). Prefrontal creatine levels did not differ across the three groups.

Conclusions

Overweight and obesity might contribute to T2DM‐related neuronal viability deficits and could be the key links that connect insulin resistance to the decreased neuronal viability in the human diabetic brain.
Long‐term renal function after treatment for unilateral, nonsyndromic Wilms tumor. A report from the St. Jude Lifetime Cohort Study
Authors: Green Daniel M. , Wang Mingjuan , Krasin Matthew J. , Davidoff Andrew M. , Srivastava DeoKumar , Jay Dennis W. , Ness Kirsten K. , Shulkin Barry L. , Spunt Sheri L. , Jones Deborah P. , Lanctot Jennifer Q. , Shelton Kyla C. , Brennan Rachel C. , Mulrooney Daniel A. , Ehrhardt Matthew J. , Gibson Todd M. , Kurt Beth A. , Robison Leslie L. , Hudson Melissa M.
Published: July 2020

Background

The impact of specific treatment modalities on long‐term renal function and blood pressure among adult survivors of Wilms tumor (WT) has not been well documented.

Methods

Among 40 WT survivors and 35 noncancer controls, we estimated the glomerular filtration rate (eGFR) using the Chronic Kidney Disease‐Epidemiology (CKD‐EPI) equations with and without cystatin C, obtained 24‐hour ambulatory blood pressure readings, and, among survivors only, measured 99mTc diethylenetriamine pentaacetic acid (DTPA) plasma clearance. Survivors were treated with unilateral nephrectomy and nonnephrotoxic chemotherapy. Twenty received whole abdomen radiation therapy (WART) [median –16.5 Gray (Gy)], and 20 received no radiation therapy. Pairwise comparisons between survivors treated with and without WART, and each group to controls were performed using two‐sample t tests.

Results

Twenty‐six (65%) WT survivors were female, and 33 (83%) were non‐Hispanic white. GFR estimated with creatinine or creatinine + cystatin C was decreased among irradiated survivors compared with controls. No irradiated or unirradiated participant had an eGFR (creatinine + cystatin C) < 60 mL/min/1.73 m2. The prevalence of hypertension was significantly increased among unirradiated (25%) and irradiated survivors (35%) compared with controls (0%). Of the 24‐hour ambulatory blood pressure monitoring parameters evaluated, only mean sleep period diastolic blood pressure load of those who received WART was significantly different from that of controls.

Conclusions

Chronic kidney disease was infrequent in long‐term survivors of unilateral nonsyndromic WT, whether treated with WART or no radiation. The prevalence of hypertension was increased in both groups compared with controls, emphasizing the need for ongoing monitoring of renal and cardiovascular health.
Vaccination in pediatric cancer survivors: Vaccination rates, immune status, and knowledge regarding compliance
Authors: Choi Daniel K. , Strzepka Jessica T. , Hunt Samantha R. , Tannenbaum Viktorya L. , Jang Inae E.
Published: July 2020

Background

Vaccination recommendations for childhood cancer survivors are ambiguous. Limited data exist on vaccination rates and patient/caregiver knowledge of vaccination postchemotherapy.

Procedure

A single‐institution study of childhood cancer survivors treated from 1996 to 2018. Study included a retrospective chart review assessing patient's vaccination status, survey of patient's/caregiver's knowledge/beliefs regarding vaccination postchemotherapy, and assessment of immunoglobulin titers.

Results

A total of 120 patient charts were included. Vaccination records were available for 82% (98/120) of patients, 57% (56/98) were up to date with vaccinations before chemotherapy, and 83% (81/98) received vaccinations after chemotherapy. Children who resumed vaccination postchemotherapy were younger at cancer diagnosis compared to those who did not resume vaccination (2 vs 4 years, P < .02). Median time since chemotherapy was higher in vaccinated versus unvaccinated patients (107 vs 60 months, P < .02). Immunoglobulin titers were assessed in 27 patients, and 74% (20/27) were not immune to one or more infections tested. Lack of immunity to pneumococcal strains was the most common. There was no difference in median age at diagnosis or time since chemotherapy completion in immune versus nonimmune patients.

In 33 surveyed patients/caregivers, 33% (11/33) were not advised about resuming vaccinations postchemotherapy. Over one‐third (12/33) of respondents were concerned about vaccination safety after chemotherapy, although 88% (29/33) agreed they would vaccinate if recommended by their pediatrician/pediatric oncologist.

Conclusions

Most childhood cancer survivors resume vaccinations postchemotherapy. Considerable variability exists in vaccination timing after chemotherapy. Pediatric oncologists play a central role in educating patients/pediatricians about vaccination recommendations postchemotherapy.
Machine learning outcome regression improves doubly robust estimation of average causal effects
Authors: Choi Byeong Yeob , Wang Chen‐Pin , Gelfond Jonathan
Published: July 2020

Background

Doubly robust estimation produces an unbiased estimator for the average treatment effect unless both propensity score (PS) and outcome models are incorrectly specified. Studies have shown that the doubly robust estimator is subject to more bias than the standard weighting estimator when both PS and outcome models are incorrectly specified.

Method

We evaluated whether various machine learning methods can be used for estimating conditional means of the potential outcomes to enhance the robustness of the doubly robust estimator to various degrees of model misspecification in terms of reducing bias and standard error. We considered four types of methods to predict the outcomes: least squares, tree‐based methods, generalized additive models and shrinkage methods. We also considered an ensemble method called the Super Learner (SL), which is a linear combination of multiple learners. We conducted simulations considering different scenarios by the complexity of PS and outcome‐generating models and some ranges of treatment prevalence.

Results

The shrinkage methods performed well with robust doubly robust estimates in term of bias and mean squared error across the scenarios when the models became rich by including all 2‐way interactions of the covariates. The SL performed similarly to the best method in each scenario.

Conclusions

Our findings indicate that machine learning methods such as the SL or the shrinkage methods using interaction models should be used for more accurate doubly robust estimators.
Non‐steroidal Anti‐inflammatory Drugs and the Risk of Pneumonia Complications: A Systematic Review
Authors: Sodhi Mohit , Khosrow‐Khavar Farzin , FitzGerald John Mark , Etminan Mahyar
Published: July 2020

There have been concerns regarding the safety of nonsteroidal antiinflammatory drugs (NSAIDs) in patients with respiratory infections. However, to date, the quality of the evidence has not been systematically assessed. The purpose of this systematic review was to evaluate the role of NSAIDs on pneumonia complications. OVID MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, and Google Scholar were searched. Studies that examined pneumonia complications in patients who had taken NSAIDs before onset of symptoms were identified. Quality assessment was conducted using the Risk of Bias in Non‐randomized Studies – of Interventions (ROBINS‐I) assessment tool, which was adapted to include biases that were pertinent to this question. The search strategy identified 1721 potential studies through the 5 primary databases and searching reference lists. Of these, 10 studies met the inclusion criteria, including 5 nested case‐control studies, 2 population‐based case‐control studies, and 3 cohort studies. In total, 59,724 adults were included from 4 of the studies (range = 57–59,250) and 1217 children from 5 studies (range = 148–540). All studies demonstrated a positive association; in adults (odds ratio/risk ratio range = 1.8–8.1) and children (odds ratio/risk ratio range = 1.9–6.8). Studies were limited by moderate or serious risk of confounding bias, exposure misclassification, and protopathic biases and sparse data bias. The results of this review demonstrate that published studies on the effect of NSAIDs use and risk of pneumonia complications are subject to a number of biases. These results should not be extrapolated as evidence of harm for NSAIDs, including ibuprofen, in respiratory ailments but highlight the need for more methodologically robust studies to evaluate this potential relationship.
Colorectal cancer patients can be advocates for colorectal cancer screening for their siblings: A study on siblings' perspectives
Authors: Tan Ker‐Kan , Lim Tian‐Zhi , Chew Emily , Chow Wen‐Min , Koh Gerald Choon‐Huat
Published: July 2020

Objective

This study was performed to explore in‐depth, the issues and barriers pertaining to colorectal cancer (CRC) screening amongst the siblings of CRC patients in view of their higher risk of developing CRC.

Methods

A qualitative study of siblings of CRC patients was performed from August 2017 to October 2018. Semi‐structured interviewed were performed until data saturation was achieved. The data was then thematically analysed.

Results

A total of 36 siblings of CRC patients, with a median age of 59 (range 39‐78) years old completed the interviews. All the interviews were conducted alone with the participants. Each interview lasted between 30 and 45 minutes. None of the participants has undergone screening colonoscopy prior to the interviews.

After thematic analysis, five themes were identified. These include: (i) Misunderstanding their own risk of developing colorectal cancer; (ii) Misperceptions of the role of “screening” for colorectal cancer.; (iii) Misconception of the CRC screening modality for FDRs; (iv) Barriers and facilitators of undergoing screening; (v) Misperceptions of national healthcare policies.

Conclusions

Identifying and addressing the identified barriers for these siblings to undergo screening colonoscopy is easily attainable. A multi‐pronged approach should also be adopted to address the various concerns so as to reduce the incidence of CRC amongst these higher risk individuals.
Optimal control of a two‐wheeled self‐balancing robot by reinforcement learning
Authors: Guo Linyuan , Rizvi Syed Ali Asad , Lin Zongli
Published: July 2020

This article concerns optimal control of the linear motion, tilt motion, and yaw motion of a two‐wheeled self‐balancing robot (TWSBR). Traditional optimal control methods for the TWSBR usually require a precise model of the system, and other control methods exist that achieve stabilization in the face of parameter uncertainties. In practical applications, it is often desirable to realize optimal control in the absence of the precise knowledge of the system parameters. This article proposes to use a new feedback‐based reinforcement learning method to solve the linear quadratic regulation (LQR) control problem for the TWSBR. The proposed control scheme is completely online and does not require any knowledge of the system parameters. The proposed input decoupling mechanism and pre‐feedback law overcome the commonly encountered computational difficulties in implementing the learning algorithms. Both state feedback optimal control and output feedback optimal control are presented. Numerical simulation shows that the proposed optimal control scheme is capable of stabilizing the system and converging to the LQR solution obtained through solving the algebraic Riccati equation.
Extending the conceptual model of river island development to incorporate different tree species and environmental conditions
Authors: Gurnell Angela M. , Bertoldi Walter
Published: July 2020

Riparian vegetation survival and establishment in gravel‐bed rivers depends on the balance between vegetation growth and flood disturbance. We present four examples of vegetation and landform development in gaps (linear open spaces) between established islands and/or floodplain within a reach of the middle Tagliamento River, Italy. Gaps offer shelter to vegetation, supporting higher colonization success and different vegetation‐landform evolution pathways. Time sequences of aerial images track vegetation development over 30 years in the four gaps. In combination with the flood disturbance time series, we interpret vegetation dynamics and identify the fate of sexual and asexual reproduction strategies by observing vegetation expansion from lines of young plants and shrubs and from uprooted deposited trees and pioneer islands, respectively. Analysis of image sequences reveals common features across the four gaps that are generalized to extend a conceptual model of island development. Growing conditions, disturbance energy and time (window of opportunity) between major floods are the main controls on vegetation colonization. These vary among rivers, among reaches along the same river and locally, as in the investigated gaps, allowing different tree species with different life history traits (e.g., Populus nigra, Alnus incana) to engineer local river landforms in different and complementary ways. Although the conceptual model is inspired by observations on the Tagliamento River, consideration of species life history traits and the joint influences of growing conditions, disturbance energy and windows of opportunity provide a framework that may be applied to other temperate rivers where trees drive landform development.
An analytical toast to wine: Using stacked generalization to predict wine preference
Authors: Larkin Taylor , McManus Denise
Published: July 2020

Due to the intricacies surrounding taste profiles, one's view of good wine is subjective. Therefore, it is advantageous to provide a more objective, data‐driven way to assess wine preferences. Motivated by a previous study that modeled wine preferences using machine learning algorithms, this work presents an ensemble approach to predict a wine sample's quality level given its physiochemical properties. Results show the proposed framework out‐performs many sophisticated models including the one recommended by the motivational study. Moreover, the proposed framework offers a simple variable importance strategy to gain insight as to the relevance of the predictor variables and is applied to both simulated and real data. Given the predictive power of using ensembles, especially when they can be interpretable, practitioners can use the following approach to provide an accurate and inferential perspective towards demystifying wine preferences.
Bayesian methods for the analysis of early‐phase oncology basket trials with information borrowing across cancer types
Authors: Jin Jin , Riviere Marie‐Karelle , Luo Xiaodong , Dong Yingwen
Published: July 2020

Research in oncology has changed the focus from histological properties of tumors in a specific organ to a specific genomic aberration potentially shared by multiple cancer types. This motivates the basket trial, which assesses the efficacy of treatment simultaneously on multiple cancer types that have a common aberration. Although the assumption of homogeneous treatment effects seems reasonable given the shared aberration, in reality, the treatment effect may vary by cancer type, and potentially only a subgroup of the cancer types respond to the treatment. Various approaches have been proposed to increase the trial power by borrowing information across cancer types, which, however, tend to inflate the type I error rate. In this article, we review some representative Bayesian information borrowing methods for the analysis of early‐phase basket trials. We then propose a novel method called the Bayesian hierarchical model with a correlated prior (CBHM), which conducts more flexible borrowing across cancer types according to sample similarity. We did simulation studies to compare CBHM with independent analysis and three information borrowing approaches: the conventional Bayesian hierarchical model, the EXNEX approach, and Liu's two‐stage approach. Simulation results show that all information borrowing approaches substantially improve the power of independent analysis if a large proportion of the cancer types truly respond to the treatment. Our proposed CBHM approach shows an advantage over the existing information borrowing approaches, with a power similar to that of EXNEX or Liu's approach, but the potential to provide substantially better control of type I error rate.
A multiple imputation‐based sensitivity analysis approach for data subject to missing not at random
Authors: Hsu Chiu‐Hsieh , He Yulei , Hu Chengcheng , Zhou Wei
Published: July 2020

Missingness mechanism is in theory unverifiable based only on observed data. If there is a suspicion of missing not at random, researchers often perform a sensitivity analysis to evaluate the impact of various missingness mechanisms. In general, sensitivity analysis approaches require a full specification of the relationship between missing values and missingness probabilities. Such relationship can be specified based on a selection model, a pattern‐mixture model or a shared parameter model. Under the selection modeling framework, we propose a sensitivity analysis approach using a nonparametric multiple imputation strategy. The proposed approach only requires specifying the correlation coefficient between missing values and selection (response) probabilities under a selection model. The correlation coefficient is a standardized measure and can be used as a natural sensitivity analysis parameter. The sensitivity analysis involves multiple imputations of missing values, yet the sensitivity parameter is only used to select imputing/donor sets. Hence, the proposed approach might be more robust against misspecifications of the sensitivity parameter. For illustration, the proposed approach is applied to incomplete measurements of level of preoperative Hemoglobin A1c, for patients who had high‐grade carotid artery stenosisa and were scheduled for surgery. A simulation study is conducted to evaluate the performance of the proposed approach.
Suppressed Jahn–Teller Distortion in MnCo2O4@Ni2P Heterostructures to Promote the Overall Water Splitting
Authors: Ge Jing , Zhang Wen , Tu Jun , Xia Tao , Chen Sanping , Xie Gang
Published: July 2020

Jahn–Teller distortion in cobalt based spinel electrocatalysts causes poor activity and stability in potentially promising catalysts for water splitting. Here, a novel strategy to resolve this problem by interface engineering is reported, in which, Jahn–Teller distortion in MnCo2O4 is significantly suppressed by in situ growth Ni2P nanosheets onto the MnCo2O4. The significance of interface engineering in suppressing Jahn–Teller distortion of Mn3+ is further investigated by X‐ray photoelectron spectroscopy, the resulting increased catalytic activity and the effects of suppressed distortion demonstrated by density functional theory calculations. The resulting MnCo2O4@Ni2P heterostructures exhibit superior electrocatalytic activity for the both oxygen evolution reaction and hydrogen evolution reaction with small overpotentials of 240 and 57 mV at 10 mA cm‐2, respectively. Furthermore, the heterogeneous composite electrode demonstrates a superior current density of 10 mA cm‐2 at a voltage of 1.63 V with excellent durability in a water splitting cell.
In Vivo Dynamic Monitoring of Bacterial Infection by NIR‐II Fluorescence Imaging
Authors: Chen Jun , Feng Sijia , Chen Mo , Li Pei , Yang Yimeng , Zhang Jian , Xu Xiaogang , Li Yunxia , Chen Shiyi
Published: July 2020

Time window of antibiotic administration is a critical but long‐neglected point in the treatment of bacterial infection, as unnecessary prolonged antibiotics are increasingly causing catastrophic drug‐resistance. Here, a second near‐infrared (NIR‐II) fluorescence imaging strategy based on lead sulfide quantum dots (PbS QDs) is presented to dynamically monitor bacterial infection in vivo in a real‐time manner. The prepared PbS QDs not only provide a low detection limit (104 CFU mL−1) of four typical bacteria strains in vitro but also show a particularly high labeling efficiency with Escherichia coli (E. coli). The NIR‐II in vivo imaging results reveal that the number of invading bacteria first decreases after post‐injection, then increases from 1 d to 1 week and drop again over time in infected mouse models. Meanwhile, there is a simultaneous variation of dendritic cells, neutrophils, macrophages, and CD8+ T lymphocytes against bacterial infection at the same time points. Notably, the infected mouse self‐heals eventually without antibiotic treatment, as a robust immune system can successfully prevent further health deterioration. The NIR‐II imaging approach enables real‐time monitoring of bacterial infection in vivo, thus facilitating spatiotemporal deciphering of time window for antibiotic treatment.
Programmable Organic‐Free Negative Differential Resistance Memristor Based on Plasmonic Tunnel Junction
Authors: Xu Chen , Li Chuanping , Jin Yongdong
Published: July 2020

A novel negative differential resistance (NDR) phenomenon is reported herein based on planar plasmonic tunnel junction, resulting from plasmon‐assisted long‐range electron tunneling (P‐tunneling) and electronic caching effect of Au@SiO2 nanoparticles. The tunnel junction is made of shell‐insulated Au@SiO2 nanoparticle nanomembrane, in which SiO2 shells act as a tunable tunneling barrier, while the Au core not only support the plasmonic effect to enable P‐tunneling, but also act as electronic caches to render NDR responses. The NDR peak voltage and current can be programmably controlled by varying the thickness of SiO2 shell and the size of Au core to tune barrier level for electron transport. In addition, light induced plasmonic effect can be further managed to regulate the NDR behavior by fine‐tuning P‐tunneling. The phenomenon is exploited for robust use as memristors. The work provides a new mechanism for the generation of NDR effect and may open a way for the development of robust and new conceptual nanoelectronic devices.
Suitability of different tests for characterization of the dimpled concrete‐to‐concrete interface
Authors: Čairović Đorđe , de la Fuente Albert , Zlámal Martin , Venclovský Jakub , Girgle František , Januš Ondřej , Štěpánek Petr
Published: July 2020

The main aim of this study was to assess the suitability of different existing test setups for the mechanical characterization of a dimpled interface obtained by casting concrete against dimpled high‐density polyethylene (HDPE) membrane. Even though this type of interface roughening is widely used, especially for monolithic connections between precast elements, to the best of the authors' knowledge there is no research providing any data regarding its roughness parameters, tension, and shear strength, nor its failure modes. To this end, a two‐fold objective was established for this research: (a) to identify and analyze, from a technical standpoint, the available test configurations for characterizing the mechanical performance of interfaces, and (b) to perform an extensive experimental program devoted to characterizing the mechanical performance of a dimpled HDPE membrane—cast concrete interface. The suitability of each test for reproducing the expected stress state and the actual resistance mechanism was analyzed. Moreover, a comparison between tension and shear tests, including its main advantages and disadvantaged are also presented.
TeraChem: A graphical processing unit‐accelerated electronic structure package for large‐scale ab initio molecular dynamics
Authors: Seritan Stefan , Bannwarth Christoph , Fales Bryan S. , Hohenstein Edward G. , Isborn Christine M. , Kokkila‐Schumacher Sara I. L. , Li Xin , Liu Fang , Luehr Nathan , Snyder James W. , Song Chenchen , Titov Alexey V. , Ufimtsev Ivan S. , Wang Lee‐Ping , Martínez Todd J.
Published: July 2020

TeraChem was born in 2008 with the goal of providing fast on‐the‐fly electronic structure calculations to facilitate ab initio molecular dynamics studies of large biochemical systems such as photoswitchable proteins and multichromophoric antenna complexes. Originally developed for videogaming applications, graphics processing units (GPUs) offered a low‐cost parallel computer architecture that became more accessible for general‐purpose GPU computing with the release of CUDA in 2007. The evaluation of the electron repulsion integrals (ERIs) is a major bottleneck in electronic structure codes and provides an attractive target for acceleration on GPUs. Thus, highly efficient routines for evaluation of and contractions between the ERIs and density matrices were implemented in TeraChem. Electronic structure methods were developed and implemented to leverage these integral contraction routines, resulting in the first quantum chemistry package designed from the ground up for GPUs. This GPU acceleration makes TeraChem capable of performing large‐scale ground and excited state calculations in the gas and condensed phase. Today, TeraChem's speed forms the basis for a suite of quantum chemistry applications, including optimization and dynamics of proteins, automated and interactive chemical discovery tools, and large‐scale nonadiabatic dynamics simulations.

This article is categorized under:

Electronic Structure Theory > Ab Initio Electronic Structure Methods

Software > Quantum Chemistry

Structure and Mechanism > Computational Biochemistry and Biophysics
Molecular modeling of organic redox‐active battery materials
Authors: Fornari Rocco Peter , de Silva Piotr
Published: July 2020

Organic redox‐active battery materials are an emerging alternative to their inorganic counterparts currently used in the commercialized battery technologies. The main advantages of organic batteries are the potential for low‐cost manufacturing, tunability of electrochemical properties through molecular engineering, and their environmental sustainability. The search for organic electroactive materials that could be used for energy storage in mobile and stationary applications is an active area of research. Computer simulations are used extensively to improve the understanding of the fundamental processes in the existing materials and to accelerate the discovery of new materials with improved performance. We will focus on two main types of redox‐active organic battery materials, that is, solid‐state organic electrode materials and organic electrolytes for redox flow batteries. Because organic materials are made of molecular building blocks, the molecular modeling methodology is usually the most appropriate to investigate their properties at the electronic and atomistic scales. After introducing the fundamentals of computational organic electrochemistry, we will survey its most recent applications in organic battery research and outline some of the remaining challenges for the development and applications of atomic‐scale modeling techniques in the organic battery context.

This article is categorized under:

Structure and Mechanism > Computational Materials Science

Software > Molecular Modeling

Electronic Structure Theory > Density Functional Theory