bluuebunny/crossref_metadata_2025 huggingface dataset:
Undiagnosed hypertension and its associated factors in Ethiopia: A systematic review and meta‐analysis
Authors: Solbana Lencho Kajela , Chaka Eshetu Ejeta , Tola Diriba Etana
Published: November 2023

Background and Aims

Early identification and treatment of hypertension could lower the risk of cardiovascular diseases; which share the largest proportion of death. The findings of previous studies done in Ethiopia on undiagnosed hypertension were inconsistent. Therefore, this systematic review and meta‐analysis aimed to assess the prevalence and associated factors of undiagnosed hypertension among adults in Ethiopia.

Methods

A protocol with registration number CRD42023395445 was registered to Prospective Register of Systematic Reviews (PROSPERO). A comprehensive search of observational studies done on undiagnosed hypertension was identified in PubMed, Google Scholar, Cochrane Library, Hinari databases, and other sources available until January 10, 2023. The quality of the identified studies using the set criteria and necessary data was extracted and exported to R version 4.2.3 and STATA version 15.0 for analysis. The pooled prevalence of undiagnosed hypertension and its associated factors were identified. The risk of bias was evaluated using a funnel plot and Egger's test. The findings were presented using tables, figures, and statements. This study was not funded by any organization.

Results

Eleven studies having 6132 participants were included in the analysis. The pooled prevalence of undiagnosed hypertension was 21% (95% confidence interval [CI]: 16–27). In subanalysis, according to the American Heart Association ( ≥ 130/80 mmHg), the pooled prevalence was 29% (95% CI: 18–40). However, according to the International Society of Hypertension ( ≥ 140/90), the pooled prevalence was 16% (95% CI: 13–20).

Sex (AOR = 2.49, 1.48–3.49), age ≥55 years (AOR = 2.68, 1.16–4.21), alcohol drinking (AOR = 2.68, 1.68–3.69), body mass index ≥25 kg/m2 (AOR = 2.62, 1.77–3.48), and high triglyceride levels (AOR = 1.87, 1.22–2.51) were significantly associated with it.

Conclusion

In Ethiopia, about one in five adults ≥ 18 years has undiagnosed hypertension; therefore raising public awareness for medical checkups, early hypertension detection, and treatment is suggested. However, these findings cannot be generalized to pediatrics.
Prostatic schwannoma discovered after laparoscopic radical prostatectomy: A case report with literature review
Authors: Bejrananda Tanan , Jakjaroenrit Nattawit
Published: November 2023

Background

Schwannomas originating in the prostate are extremely rare. We present a case of prostatic schwannoma in a 66‐year‐old male with lower urinary tract symptoms. Preoperative evaluation revealed a prostatic mass, and the definitive diagnosis was made through laparoscopic radical prostatectomy.

Case presentation

A 66‐year‐old male presented with persistent lower urinary tract symptoms for 5 years and a prostate‐specific antigen level of 0.63 ng/mL. MRI showed a well‐defined solid cystic mass in the posterolateral basal right peripheral zone, causing superior displacement of the right seminal vesicle. Laparoscopic radical prostatectomy was performed, confirming a periprostatic schwannoma.

Conclusion

This case highlights the rarity of prostatic schwannomas and their association with lower urinary tract symptoms. MRI plays a crucial role in identifying prostatic masses, while laparoscopic radical prostatectomy can serve as a diagnostic and therapeutic approach for prostatic schwannomas. Increased awareness of this rare entity is essential for accurate diagnosis and optimal management.
MAEU‐NET: A novel supervised architecture for brain tumor segmentation
Authors: Kumar Sangeet , Biswal B.
Published: November 2023

A brain tumor is an abnormal growth of cells that damages the neural system and may lead to severe conditions. These cells are irregular in shape and size, and as a result, the manual analysis of these cells from magnetic resonance (MR) images is a cumbersome and time‐consuming task. To alleviate these issues, a novel U‐Net inspired MAEU‐Net (Multiscale context Aggregation and Edge activation U‐Net) is implemented to detect the brain tumor pixels from MR images more precisely. The encoder block of the proposed model is improved by integrating with multiscale feature aggregation and convolution block attention modules (CBAM) enabling the model to extract both pertinent low‐level and high‐level features. Further, the extracted features are subjected to a parallel pooling module to elevate the features that extract the tumor pixels. In addition to this, the output features of the last encoder are fed to a parallel dilated context aggregation module to mitigate the hyper‐parameter size and further elevate the receptive field strength of the proposed model. Apart from this, edge‐enhanced modules are incorporated with skip connections which concatenate the feature maps of the decoder with respective edge‐enhanced encoder feature maps. As a result, this module increases the aspect ratio and reduces blurry edge problems. To illustrate the performance of the proposed MAEU‐Net, it is trained and tested using Kaggle LGG, BraTS 2018, and BraTS 2021 publicly available datasets. The proposed model outperformed the previously existing models by achieving the test loss, dice coefficient, sensitivity, and specificity of 0.0590, 0.901, 0.942, and 0.998, respectively. Simultaneously, the proposed model is quantitatively analyzed by performing ablation and comparative studies and presented that the proposed MAEU‐Net is superior to other previous existing models like U‐Net++, SegNet, etc.
Atomic tracking of thermally‐driven structural evolution in 2D crystals: Case of NbSe2
Authors: Hou Baofei , Zhang Teng , Wang Tingting , Ji Hongyan , Yang Huixia , Jia Liangguang , Han Xu , Qiao Jingsi , Zhang Yu , Liu Liwei , Gao Hong‐Jun , Wang Yeliang
Published: November 2023

Advanced atomic tracking techniques play a critical role in characterizing structural evolution, elucidating fundamental mechanisms of exotic phenomena and tailoring delicate properties. Thermally driven structural modulation in 2D crystals, such as the charge density wave (CDW), often leads to intriguing quantum properties, making them a valuable platform for exploring fundamental physics and potential device applications. However, despite their significance, experimental studies addressing atomic tracking of thermally‐driven structural evolution in 2D crystals have been limited. Herein, we utilize high‐accuracy variable‐temperature atomic tracking measurements with scanning tunneling microscopy (STM) to directly observe a series of structural transitions in a model 2D crystal, namely NbSe2. With the atomic tracking technique, we confirm the existence of the universal thermally‐driven CDW transition hysteresis between the heating and cooling cycles. This transition hysteresis, characterized by a constant temperature offset, represents a new phenomenon of structural evolution. Our findings provide a feasible method to track CDW transitions at the atomic scale in 2D crystals, significantly contributing to a better understanding and the potential modulation of these materials' functions in nanodevices.

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Pharmacists' perceived barriers and facilitators as immunisers: Mapping COM‐B model to support intervention development
Authors: Teo Chien Ying , Yaw Xin Er , Kum Yi Ling , Chia Ee Vy , Heng Wei Shan , Khan Tahir Mehmood , Saw Pui San
Published: November 2023

Introduction

Pharmacists were involved in the education and facilitation of vaccine administration, including more recent roles in vaccine administration. Yet there is a lack of reviews about pharmacists' motivation as immunisers to improve understanding of the possible gaps in the uptake of the professional roles.

Objective

This review aimed to identify perceived barriers and facilitators of pharmacists as immunisers and mapped across the Capability, Opportunity, and Motivation Model of Behavior (COM‐B).

Methods

A total of 5429 articles were identified in four databases from inception until December 2022. Studies exploring pharmacists' perceptions and attitudes toward their role in vaccine administration were included. Using thematic analysis, the findings were mapped onto the COM‐B model components. All findings are reported following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guideline.

Results

Twenty‐six studies were included in the review. Themes of facilitators and barriers were identified in components of physical capability (training and certificate program), psychological capability (knowledge and awareness), physical opportunity (time and space), social opportunity (support from patients, staff, and general practitioners), reflective motivation (cost and expansion of role) and automatic motivation (legislation and reimbursement).

Conclusion

By integrating these findings into the COM‐B framework, a holistic roadmap can assist policymakers in aligning strategies for effective pharmacist‐led vaccinations.
α‐bisabolol β‐d‐fucopyranoside (ABFP) ameliorates scopolamine‐induced memory deficits through cholinesterase inhibition and attenuation of oxidative stress in zebrafish (Danio rerio)
Authors: Jeyakumar Mahalingam , Jaya Balan Devasahayam , Kiruthiga Chandramohan , Jafni Sakthivel , Pandima Devi Kasi
Published: November 2023

Alzheimer's disease (AD) is one of the major devastating neurodegenerative disorders associated with the gradual decline of an individual's memory, cognition, and ability to carry out day‐to‐day activities. In the present study, the neuroprotective ability of α‐bisabolol β‐d‐fucopyranoside (ABFP) was assessed via measurement of antioxidant parameters like lipid peroxidation, glutathione peroxidation, glutathione, protein carbonyl content assays, and caspase‐3 activity estimation. Moreover, the acute toxicity of ABFP was estimated in the zebrafish larval model. The results showed that ABFP exhibits little to no toxicity at lower concentrations in the acute toxicity test. ABFP‐pretreated and scopolamine‐exposed fish exhibited more exploratory behavior in the behavior assay than scopolamine‐only induced groups. Additionally, the results of antioxidant enzyme assays revealed reduced oxidative stress and damage in ABFP‐treated fish, while enzyme activity experiments carried out with brain homogenate from ABFP‐treated fish showed decreased acetylcholinesterase enzyme activity. Overall, it can be concluded that ABFP has the potential to be a promising agent for the treatment of AD in the future.
The moral superiority of temporal (vs. social) comparisons
Authors: Dagogo‐Jack Sokiente W.
Published: November 2023

Brands often encourage consumers to compare themselves to two types of standards: other people (i.e., social comparisons) and their own past (i.e., temporal comparisons). Although research has drawn many parallels between these two self‐comparisons, relatively little work has examined how they diverge. Moreover, existing research on their differences focuses on individuals engaging in—rather than brands encouraging—different self‐comparisons. The present research identifies moral perceptions as one critical dimension on which brand‐elicited temporal and social comparisons differ. Four studies find that evoking downward social (vs. temporal) comparisons undermines brand morality perceptions and, consequently, brand evaluations and choice. Providing preliminary insight into the mechanism, when brands evoke downward social (vs. temporal) comparisons, consumers perceive them as promoting status‐seeking behavior, which mediates morality judgments. Furthermore, the effects of comparison type are eliminated among consumers with stronger status motives—those who are less prone to condemn status‐seeking behavior. Altogether, these findings reveal a lay belief in the moral superiority of downward temporal (vs. social) comparisons and the downstream consequences for brands that elicit such comparisons.
The value of a dynamic echocardiographic approach to diastolic dysfunction in intensive care medicine
Authors: Catena Emanuele , Volontè Alessandra , Rizzuto Chiara , Bergomi Paola , Gambarini Matteo , Fossali Tommaso , Ottolina Davide , Perotti Andrea , Veronese Alice , Colombo Riccardo
Published: November 2023

Diastolic dysfunction is an underestimated feature in the context of the critically ill setting and perioperative medicine. Advances in echocardiography, its noninvasive, safe and easy use, have allowed Doppler echocardiography to become a cornerstone for diagnosing diastolic dysfunction in clinical practice. The diagnosis of diastolic dysfunction and increased filling pressures is nevertheless complex. Using an echocardiographic assessment and the routine application of preload stress maneuvers during echocardiographic examination can help identify early stages of diastolic dysfunction leading to better management of patients at risk of acute heart decompensation in the perioperative period or during ICU stay.
Association between gut microbiota and seven gastrointestinal diseases: A Mendelian randomized study
Authors: Zhu Shuang Jing , Ding Zhen
Published: November 2023

Background

Observational research has shed light on the ability of gut microbes to influence the onset and progression of gastrointestinal diseases. The causal relationships between specific gut microbiomes and various gastrointestinal conditions, however, remain unknown.

Methods

We investigated the relationship between gut microbiota and seven specific gastrointestinal disorders using a robust two‐sample Mendelian randomization (MR) approach. The inverse variance‐weighted (IVW) method was used as the primary analysis tool in our study. Furthermore, we conducted multiple sensitivity analyses to strengthen the robustness of our findings and ensure the reliability of the IVW method.

Results

Our research has discovered significant links between the composition of gut microbiota and a variety of gastrointestinal ailments. We found compelling links between 13 gut microbiota and fatty liver, four gut microbiota and cirrhosis, eight gut microbiota and hepatocellular carcinoma, four gut microbiota and cholelithiasis, 12 gut microbiota and acute pancreatitis, eight gut microbiota and chronic pancreatitis, and 11 gut microbiota and pancreatic cancer. These findings shed light on the intricate relationship between gut microbes and the emergence of these specific gastrointestinal conditions.

Conclusions

The findings of this extensive study not only validate the potential role of specific gut microbiota in gastrointestinal diseases, but also fill a critical gap in previous research. The discovery of these specific gut microbiota is a significant step forward because they may serve as novel and promising biomarkers for both the prevention and treatment of gastrointestinal conditions.
Regional variation of climatological cloudburst frequency estimated from historical observations of daily precipitation sums
Authors: Schmith Torben , Thejll Peter , Vejen Flemming , Christiansen Bo
Published: November 2023

This study aims to estimate climatological cloudburst frequencies from daily precipitation sums for a dense network of 161 historical Danish stations covering the period 1914–2010, in order to reveal any systematic regional differences. We define a cloudburst day for a given station as a day when the maximum 1‐h precipitation sum exceeds a predefined threshold; we use the thresholds 15, 20 and 25 mm, corresponding to a cloudburst frequency around 0.42, 0.16 and 0.06 year−1, respectively. Supplementing the historical data, we use hourly data from a modern network and relate the daily probability of cloudburst occurrence to the corresponding daily precipitation using binary regression. This allows an estimation of the cloudburst frequency from a series of daily sums. To validate the methods, we use 33 stations that have been operating for 30 years or longer. For these stations, we demonstrate significant skill by comparing observed and estimated cloudburst frequencies with a jackknife procedure. By applying the model to the 161 historical series, we estimate climatological cloudburst frequencies throughout Denmark. We find large systematic regional variations across Denmark and these variations are much larger, but with a similar regional pattern, than obtained by previous work. We suggest applying the approach to the historical daily precipitation series that exist across the world.
Paediatric pyoderma gangrenosum treated with ustekinumab
Authors: Savasta Emanuele , Coppo Paola , La Selva Roberta , Opramolla Anna , Pinon Michele
Published: November 2023

Pyoderma gangrenosum (PG) is a rare reactive noninfectious inflammatory dermatosis. More than 50% of PG patients have an associated systemic disease, which, in most cases, is an inflammatory bowel disease. PG affects more females than males and patients with active colitis. This case report describes a 12‐year‐old girl previously diagnosed with ulcerative colitis (UC) and on infliximab treatment. She came to our attention with a painful leg ulcer during admission for acute respiratory failure and fever. The lesion was classified as PG and a diagnosis of UC pulmonary involvement was made. Infliximab was substitute by ustekinumab and the girl is in remission after 1 year of treatment. To the best of our knowledge, this is the first case in the literature of a UC‐related paediatric PG treated with ustekinumab. Our data suggest that more studies are required as to the efficacy of ustekinumab in paediatric PG settings.
Normal Variations in Upper Esophageal Sphincter Function During Deglutition: A Secondary Analysis of Videofluoroscopic Data
Authors: Ambrocio Kevin Renz , Ramsey Reagan , O'Rourke Ashli , Beall Jonathan , Garand Kendrea L.
Published: November 2023

Objective

Cricopharyngeal dysfunction is a common potential cause of pharyngoesophageal dysphagia. Contextual factors (i.e., personal demographics and bolus properties) appear to impact upper esophageal sphincter (UES) function but have yet to be assessed collectively in a large‐scale study using psychometrically sound swallow task procedures. Using a standardized and validated videofluoroscopic approach, we investigated the collective effects of age, sex, and swallow task on UES opening duration (UESOdur) and UES maximum distension (UESmax) in a large sample of healthy adults.

Methods

UESOdur and UESmax data were analyzed from existing videofluoroscopic images of 195 healthy adults (21–89 years old) across seven swallow tasks (thin liquid to viscous liquids, puree, and a solid). Generalized estimating equation modeling captured the effects of the aforementioned contextual factors (α = 0.05).

Results

UESOdur significantly increased with age, while UESmax had an inverse relationship. Females had significantly wider UESmax. UESOdur of 5 mL thin liquid was significantly shorter than all other liquid swallow tasks, while solid had an inverse effect. Compared to 5 mL thin liquid, all other swallow tasks resulted in significantly wider UESmax. Mildly and moderately thick liquid significantly increased UESOdur when isolating viscosity. UESmax was significantly wider with mildly and moderately thick liquid and puree than thin liquid. When isolating volume, cup sip thin liquid increased both measures significantly relative to 5 mL.

Conclusion

Age, sex, and swallow task can influence the normal timing and extent of UES movement. These collective effects contribute to normal variability in UES function and should be considered for clinical decision‐making.

Level of Evidence

4 Laryngoscope, 134:2306–2315, 2024
Natural History of KCNQ4p.G285S Related Hearing Loss, Construction of iPSC and Mouse Model
Authors: Zhang Xiaolong , Shi Tao , Li Jin , Wu Xiaonan , Wu Kaili , Li Danyang , Wang Dayong , Guan Jing , Wang Hongyang
Published: November 2023

Objective

KCNQ4 is one of the most common disease‐causing genes involved in autosomal dominant non‐syndromic hearing loss. We previously found that patients with KCNQ4 p.G285S exhibited a much more rapid deterioration in hearing loss than those with other KCNQ4 variants. To determine the rate of hearing loss and assess the disease for further analysis, we performed a long‐term follow‐up of these patients and generated patient‐derived induced pluripotent stem cells (iPSCs), and a mouse model.

Methods

Patients with KCNQ4 p.G285S from a five‐generation family with hearing loss were followed up from 2005 to 2022. iPSCs were generated by stimulating peripheral blood mononuclear cells from the proband, and their pluripotency was determined. The Kcnq4 p.G286S mouse model was generated using CRISPR/Cas9, and its genotype and phenotype were identified.

Results

(1) The annual rates of hearing loss at the frequencies of speech were 0.96 dB for the proband and 0.87 dB for his father during the follow‐up period, which were faster than patients with other KCNQ4 variants. (2) The patient‐derived iPSC line carrying KCNQ4 p.G285S, possessed the capacity of differentiation and pluripotency capacities. (3) Mutant mice with Kcnq4 p.G286S exhibited hearing loss and outer hair cell loss at 1 month of age.

Conclusion

Patients with KCNQ4 p.G285S variant exhibited significantly accelerated progression of hearing loss compared to those with other reported variants. Awareness of the natural history of hearing loss associated with KCNQ4 p.G285S is beneficial for genetic counseling and prognosis. The generation of the iPSCs and mouse model can provide a valuable foundation for further in‐depth analyses.

Level of Evidence

4 Laryngoscope, 134:2356–2363, 2024
Establishing an early indicator for data sharing and reuse
Authors: Piękniewska Agata , Haak Laurel L. , Henderson Darla , McNeill Katherine , Bandrowski Anita , Seger Yvette
Published: November 2023

Funders, publishers, scholarly societies, universities, and other stakeholders need to be able to track the impact of programs and policies designed to advance data sharing and reuse. With the launch of the NIH data management and sharing policy in 2023, establishing a pre‐policy baseline of sharing and reuse activity is critical for the biological and biomedical community. Toward this goal, we tested the utility of mentions of research resources, databases, and repositories (RDRs) as a proxy measurement of data sharing and reuse. We captured and processed text from Methods sections of open access biological and biomedical research articles published in 2020 and 2021 and made available in PubMed Central. We used natural language processing to identify text strings to measure RDR mentions. In this article, we demonstrate our methodology, provide normalized baseline data sharing and reuse activity in this community, and highlight actions authors and publishers can take to encourage data sharing and reuse practices.
The Role of Electron‐Donating Subunits in Cross‐Linked BODIPY Polymer Films
Authors: Özdemir Mücahit , Köksoy Baybars , Yalçın Bahattin , Koyuncu Sermet
Published: November 2023

A new method for synthesizing cross‐linked 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacenes (BODIPYs) using a radical‐based thiol‐ene click reaction is developed. This method is simple, efficient, and cost‐effective, and it produces polymers with unique optical, electrochemical, and surface morphology properties. Significant blue shifts in absorption and photoinduced electron transfer in emissions are observed in the cross‐linked BODIPY thin films. Cross‐linking also leads to the restriction of conjugation, which results in the breakage of the terminal vinyl group, an increase in the oxidation potential, and a slight upshift in the HOMO position. As a result, the electrochemical band gap is widened from 1.88 to 1.94 eV for polymer bearing N,N‐dimethylamino‐BODIPY and from 1.97 to 2.02 eV for polymer bearing N,N‐diphenylamino‐BODIPY moieties. Monomer thin films form planar surfaces due to crystallinity, while amorphous cross‐linked BODIPY polymers form more rough surfaces. Additionally, photopatterning on the film surface is successfully performed using different patterned masks. This new method for synthesizing cross‐linked BODIPYs has the potential to be used in a variety of applications, including organic electronics, bioimaging, and photocatalysis.
Correlation between a commercial electrophysiological test of sudomotor function and intraepidermal nerve fiber density in hereditary transthyretin amyloidosis
Authors: Masuda Teruaki , Misumi Yohei , Nomura Toshiya , Yamakawa Shiori , Tasaki Masayoshi , Obayashi Konen , Ando Yukio , Ueda Mitsuharu
Published: November 2023

Introduction/Aims

In the early stage, hereditary transthyretin (ATTRv) amyloidosis predominantly affects small nerve fibers, resulting in autonomic dysfunction and impaired sensation of pain and temperature. Evaluation of small fiber neuropathy (SFN) is therefore important for early diagnosis and treatment of ATTRv amyloidosis. Herein, we aimed to investigate the accuracy of a quick and non‐invasive commercial sudomotor function test (SFT) for the assessment of SFN in ATTRv amyloidosis.

Methods

We performed the SFT in 39 Japanese adults with ATTRv amyloidosis, and we analyzed the correlations between electrochemical skin conductance (ESC) values obtained via the SFT and the parameters of other neuropathy assessment methods.

Results

ESC in the feet demonstrated significant, moderate correlations with intraepidermal nerve fiber density (IENFD) results (Spearman's rank correlation coefficient [rs], 0.58; p < .002) and other neuropathy assessment methods including the sensory nerve action potential amplitude in the nerve conduction studies (rs, 0.52; p < .001), the Neuropathy Impairment Score (rs, −0.45; p < .01), the heat‐pain detection threshold (rs, −0.62; p < .0001), and the autonomic section of the Kumamoto ATTRv clinical score (rs, −0.53; p < .0001).

Discussion

In this study, we found that ESC values in the feet via the SFT demonstrated significant, moderate correlations with IENFD and other SFN assessment methods in patients with ATTRv amyloidosis, suggesting that the SFT appears to be an appropriate method for assessment of SFN in this disease.
Characterization of polymer foam evolution in unpressurized melt systems
Authors: Pritchard Alex J. , Martin Peter J. , McCourt Mark P. , Kearns Mark P. , Cunningham Eoin
Published: November 2023

The evolution of foam in unpressurized melt processing techniques, such as rotational molding, is different from high‐pressure processes like injection foam molding, making comparisons difficult. This has driven the need for a dedicated technique for studying these systems. A unique test procedure was developed to capture and characterize foam evolution in test tubes under unpressurized conditions. A validation study found the procedure to be reliable, producing repeatable samples (height average (AVG) 39.69 ± 1.70 mm and density AVG 0.319 ± 0.012 g/cm3) and delivering comparable results to samples produced using the industrial rotational foam molding process. A study examined the effect of polymer particle size on the foam structures produced. Finer (>90 μm <106 μm) polymer powders produced more desirable structures, achieving 38.6% lower foam density and 43.8% taller peak foam height than coarser powders (>425 μm < 500 μm). Cycle times were much shorter (~15 min) in comparison with the industrial rotational molding process (>40 min) and required smaller amounts of materials, making it useful for rapid characterization. Future work is planned to apply the new procedure to investigate the effects of material and processing conditions on the foam structures produced under unpressurized conditions.

Highlights

Evaluation of existing unpressurized foam characterization methods.

Rapid test procedure developed to characterize unpressurized foam evolution.

Variability study of foam structures produced using the new procedure.

Effect of rotational molding polymer powder and considerations for foaming.

Results validated with industrial unpressurized rotationally molded samples.
Studies of Structural, Optical, and Electrical Properties of Eco‐Friendly Complex Ferroelectrics: BaTiO3–Bi0.5Na0.5TiO3
Authors: Sahu Preetisnigdha , Choudhary Ram Naresh Prasad , Samal Satish K.
Published: November 2023

Some lead‐free complex compounds containing the two perovskite compounds BaTiO3 and Bi0.5Na0.5TiO3 of chemical composition (Ba1–xBix/2Nax/2)TiO3 (x = 0, 0.05, 0.1, 0.15) are fabricated using a cost‐effective mixed oxide method. Synthesis and characterization (electrical, ferroelectric, and optical) of the above‐defined complex ferroelectrics are reported in this article. Analysis of the X‐ray diffraction data/pattern reveals the formation of phase pure compounds with tetragonal symmetry. Determination of particle size is done using the Scherrer formula. A morphology study of sintered (at 1100 °C) pellets indicates that average grain size decreases with an increase in Bi/Na content of Bi0.5Na0.5TiO3. Studies of Fourier transform infrared spectroscopy and ultraviolet–visible–near‐infrared spectroscopy reveal the type of chemical bonds present in the materials. The energy bandgaps of the compounds are found to be suitable for optical device applications. The frequency and temperature dependence of the dielectric study reveals that the dielectric constant increases and loss tangent decreases with an increase in Bi/Na content of Bi0.5Na0.5TiO3. The analysis of the I–V plot and the field‐dependent polarization (P–E hysteresis loop) provide the low leakage current and existence of ferroelectricity at room temperature, respectively.
A stereo visual navigation method for docking autonomous underwater vehicles
Authors: Xu Shuo , Jiang Yanqing , Li Ye , Wang Bo , Xie Tianqi , Li Shuchang , Qi Haodong , Li Ao , Cao Jian
Published: November 2023

Recovering and recharging autonomous underwater vehicles (AUVs) on a regular basis allows for long‐term underwater activities. This research provides a vision‐based navigation strategy for AUVs to independently identify and reconstruct the docking station (DS). The proposed framework includes a light beacon detection approach, a filter‐based light beacon matching method, and a fusion pose estimation method for DS positioning. Four green LED light beacons are mounted symmetrically on the docking ring, enabling the stereo camera to observe them from close range. A method for detecting light beacons is proposed that assures detection accuracy by identifying false positives. On a single frame from a stereo camera, filter‐based matching follows the light beacons precisely. In addition, we construct a position estimate method that significantly improves accuracy and efficiency by consisting of analyzation and iteration. A series of virtual and real‐world experiments demonstrate that our methodology can provide AUVs with reliable docking navigation.
Statistical inference for time‐to‐event data in non‐randomized cohorts with selective attrition
Authors: Wang Tuo , Mao Lu , Cocco Aldo , Kim KyungMann
Published: November 2023

In multi‐season clinical trials with a randomize‐once strategy, patients enrolled from previous seasons who stay alive and remain in the study will be treated according to the initial randomization in subsequent seasons. To address the potentially selective attrition from earlier seasons for the non‐randomized cohorts, we develop an inverse probability of treatment weighting method using season‐specific propensity scores to produce unbiased estimates of survival functions or hazard ratios. Bootstrap variance estimators are used to account for the randomness in the estimated weights and the potential correlations in repeated events within each patient from season to season. Simulation studies show that the weighting procedure and bootstrap variance estimator provide unbiased estimates and valid inferences in Kaplan‐Meier estimates and Cox proportional hazard models. Finally, data from the INVESTED trial are analyzed to illustrate the proposed method.
Engineering Photocatalytic Porous Organic Materials for Directing Redox versus Energy Transfer Processes
Authors: López-Magano Alberto , Solans-Monfort Xavier , Salaverri Noelia , Marzo Leyre , Mas-Ballesté Rubén , Alemán José
Published: November 2023

Two organic materials containing phenanthroline and triazine fragments, but connected in different ways, are presented. The imine‐based material Phen–Tz–covalent organic framework (COF) preferentially shows photocatalytic activity through an energy transfer pathway as observed for olefin photoisomerization. However, an analogous covalent triazine framework (Phen–CTF) behaves as a powerful photoredox catalyst able to activate CX (X=Br, Cl) bonds. The analysis of this phenomenon by means of theoretical calculations enables the rationalization of the different photocatalytic behavior observed. Phen–CTF behaves as a donor–acceptor material resulting in efficient charge separation upon excitation, while the imine groups present in Phen–Tz–COF hamper charge separation contributing to the rapid recombination between electrons and holes. This justifies a better activation via electron transfer in Phen–CTF and via energy transfer in Phen–Tz–COF.
Assessment of the Required Maximum‐Power‐Point‐Tracking Speed for Vehicle‐Integrated Photovoltaics Based on Transient Irradiation Measurements and Dynamic Electrical Modeling
Authors: Salomon Leon , Wetzel Gustav , Krügener Jan , Peibst Robby
Published: November 2023

Fast changing irradiation on vehicle‐integrated photovoltaic (VIPV) modules may impose demanding requirements for maximum power point tracking (MPPT) to ensure high energy conversion efficiency. In this work, the results of simulations regarding the output and efficiency of an exemplary VIPV module under real‐life irradiation conditions as measured with high time resolution are resulted. Herein, resistive as well as voltage source load is used as two idealized models of the MPPT. The simulations show that, in most cases, tracking with a resistive load at 1 Hz preserves above 90%relof the convertible energy determined by the cell performances under given irradiance levels. With a voltage source load, these values do not undercut 97%relat 0.1 Hz. Herein, it is also found that partial shading across the exemplary series connected module can reduce the converted energy in the range of 5–10%relin relation to complete negligence of this effect.
Development and validation of high‐performance thin‐layer chromatography method for simultaneous estimation of α‐Amyrin, Betulin, and β‐Sitosterol in Leptadenia reticulata and Marsdenia tenacissima
Authors: Robert Sahaya Mercy Jaquline , Aeri Vidhu
Published: November 2023

High‐performance thin‐layer chromatography (HPTLC), a top‐notch technique in the field of analysis, is quite irreplaceable when it comes to identifying and standardizing medicinal plants. Marsdenia tenacissima and Leptadenia reticulata have claimed traditional uses like anti‐cancer, anti‐inflammatory, anti‐depressant, hepatoprotection, etc., with few similar phytoconstituents. In this study, a precise and validated HPTLC densitometric method was developed for the identification of α‐amyrin, β‐sitosterol, and betulin in the above‐mentioned plants by static maceration with ethanol and aqueous‐ethanol extracts. The developed method was evaluated by linearity, range, accuracy, precision, limit of detection, limit of quantification, robustness, and specificity. The markers were subjected to ascending development with toluene: ethyl acetate: glacial acetic acid at a ratio of 8:1.5:0.5 v/v/v, air‐dried, and derivatized with anisaldehyde‐sulfuric acid. The retardation factor values of the markers were found to be 0.63 (α‐amyrin), 0.52 (β‐sitosterol), and 0.64 (betulin) for L. reticulata, and 0.55 (α‐amyrin), 0.45 (β‐sitosterol), and 0.57 (betulin) for M. tenacissima. The chromatographic results suggest that the developed method suits all three markers and can be simultaneously identified in both plants.
Comparative physiological response of filamentous cyanobacteria Phormidium tenue and Leptolyngbya lignicola under chromium (VI) stress
Authors: Mishra Prateeksha , Panda Bhabatarini
Published: November 2023

Numerous technologies for cleaning the environment without producing hazardous waste products have arisen in response to the rise in environmental pollution. Industrialization and the growing population have put society to a hard test. Continuous discharge of heavy metals (chromium, nickel, copper, mercury etc.) in water bodies is increasing by anthropogenic activities; these cause bio accumulation and shift towards a resistant microbial community. These hazardous metals enter the human body through water and food, creating a slew of health issues. Chromium (VI) is one such toxic pollutant and is more toxic than chromium (III). Several environment‐friendly technologies have been developed for decontaminating wastewater by using microorganisms. Microalgae, cyanobacteria, bacteria and fungi are used for heavy metals eradication from the water due to their metal tolerance, bioaccumulation and biotransformation capacity. In this study two cyanobacteria strains were compared for their physiological response and metal tolerance for Cr (VI) stress. Leptolyngbya lignicola and Phormidium tenue were grown in a medium containing various concentrations of chromium (1 ppm, 2 ppm, 3 ppm, 4 ppm, 5 ppm, and 10 ppm), and biochemical parameters (chlorophyll, carotenoids, protein, proline, amino acid, carbohydrate, reducing sugar and lipid content) were measured. The findings revealed that P. tenue was more sensitive to metal stress than L. lignicola. P. tenue showed a decreasing trend for all biochemical parameters except proline at higher ad lower doses of Cr (VI) stress. However L. lignicola showed an increase in biomass (6.09%) and other biochemical parameters over control at lower metal stress concentration (1 ppm), whereas, a gradual decrease in all parameters except proline was observed at higher concentrations. Further L. lignicola showing high tolerance index can be preferred for metal remediation from the water bodies of heavy metal contaminated area.
Environmental impact of quarrying on air quality in Ebonyi State, Nigeria
Authors: Okafor Odera Chukwumaijem , Njoku Chima , Akwuebu Anselem Nwabuaku
Published: November 2023

The insatiable demand for rock supplies has enticed numerous building and construction enterprises to participate in stone quarrying. This paper examines the environmental impact of quarrying on air quality in Ebonyi State, Nigeria. To achieve the main aim of the study, an objective was set to detect air pollutants at the quarry sites. A total of 220 air samples were measured from six points around the quarry locations and recorded in situ for analysis. The samples were measured three times a day (morning, afternoon, and evening) for three days. Gas monitors were used to monitor air pollutants. The generated data were subjected to completely random design (CRD) sampling techniques. The separation of means and tests was performed using Fisher's Least Significant Difference (FLSD) at a significance probability level of 5%. Based on statistical analysis, the findings detected significantly higher concentration levels of particulate matter, nitrogen dioxide, hydrogen sulfide, carbon monoxide, sulfur dioxide, chlorine, volatile organic compounds, ammonia, and hydrogen cyanide in the quarry areas than the value detected in the control area. The findings also confirmed higher noise levels in the locations. It was also observed that the concentration levels of the parameters differed from point to point and at different times of the day. This really means the occurrence of a high rate of air pollution in the study locations. Based on the above findings, it is highly recommended that air pollution control equipment be installed at quarry sites in order to reduce gaseous (pollutant) emissions.
Generalized free energy and dynamical state transition of the dyonic AdS black hole in the grand canonical ensemble
Authors: Liu Conghua , Li Ran , Zhang Kun , Wang Jin
Published: November 2023

Abstract

We study the generalized free energy of the dyonic AdS black hole in an ensemble with varying electric charge qE and fixed magnetic charge qM. When we adjust the temperature T and the electric potential ΦE of the ensemble, the Ricci scalar curvature R and electromagnetic potential Au usually diverge at the horizon. We regularize them and incorporate the off-shell corrections into the Einstein-Hilbert action. Alternatively, we find that the off-shell corrections can also be obtained by adding a boundary near the horizon to exclude the singularities. Ultimately, we derive the generalized free energy which is consistent with the definition of the thermodynamic relations. Based on the generalized free energy landscape, we can describe the dynamics of state transition as a stochastic process quantified by the Langevin equation. The path integral framework can be formulated to derive the time-dependent trajectory of the order parameter and the time evolution of the transition probability. By comparing the probability with the result of the classical master equation, we attribute the contribution to the probability of one pseudomolecule or antipseudomolecule (the instanton and anti-instanton pairs) to the rate of state transition. These results are consistent with the qualitative analysis of the free energy landscape.
On spinning strings in I-brane background
Authors: Biswas Sagar
Published: November 2023

Abstract

We revisit semiclassical strings, in particular we focus on rigidly rotating strings, in the near horizon geometry of two orthogonal stacks of NS5-branes (I-branes) using the string sigma model. We determine the conserved charges for the probe string moving in the resulting ℝt×$$ {S}_{\theta_1}^3 $$Sθ13×$$ {S}_{\theta_2}^3 $$Sθ23background supported by NS-NS two-forms and find a regularized dispersion relation for different values of integration constants. Using configurations that move simultaneously on both spheres, we obtain the giant magnon like dispersion relation for one particular set of parameters, while other consistent set of values gives us a dispersion relation reminiscent of the single spike.
De Sitter vacua — when are ‘subleading corrections’ really subleading?
Authors: Bento Bruno Valeixo , Chakraborty Dibya , Parameswaran Susha , Zavala Ivonne
Published: November 2023

Abstract

We consider various string-loop, warping and curvature corrections that are expected to appear in type IIB moduli stabilisation scenarios. It has recently been argued, in the context of strongly-warped LVS de Sitter vacua, that it is impossible to achieve parametric suppression in all of these corrections simultaneously [1]. We investigate corrections in the context of the recently discovered weakly-warped LVS de Sitter vacua, which represent a distinct branch of solutions in type IIB flux compactifications. The weakly-warped solution is supported by small conifold flux numbers MK ≲ 32, but still requires a large flux contribution to the D3-tadpole, now from the bulk. Warping corrections become less problematic, and some corrections even help to reach the weakly-warped regime of parameter space. Other corrections continue to be dangerous and would require numerical coefficients to be computed — and found to be small — in order not to destroy the consistency of the weakly-warped LVS de Sitter solution. We motivate why this may be possible.
An effective field theory for non-maximal quantum chaos
Authors: Gao Ping , Liu Hong
Published: November 2023

Abstract

In non-maximally quantum chaotic systems, the exponential behavior of out-of-time-ordered correlators (OTOCs) results from summing over exchanges of an infinite tower of higher “spin” operators. We construct an effective field theory (EFT) to capture these exchanges in (0 + 1) dimensions. The EFT generalizes the one for maximally chaotic systems, and reduces to it in the limit of maximal chaos. The theory predicts the general structure of OTOCs both at leading order in the 1/N expansion (N is the number of degrees of freedom), and after resuming over an infinite number of higher order 1/N corrections. These general results agree with those previously explicitly obtained in specific models. We also show that the general structure of the EFT can be extracted from the large q SYK model.
Radiative neutrino masses and the Cohen-Kaplan-Nelson bound
Authors: Adolf Patrick , Hirsch Martin , Päs Heinrich
Published: November 2023

Abstract

Recently, an increasing interest in UV/IR mixing phenomena has drawn attention to the range of validity of standard quantum field theory. Here we explore the consequences of such a limited range of validity in the context of radiative models for neutrino mass generation. We adopt an argument first published by Cohen, Kaplan and Nelson that gravity implies both UV and IR cutoffs, apply it to the loop integrals describing radiative corrections, and demonstrate that this effect has significant consequences for the parameter space of radiative neutrino mass models.
Optimality of the Decay Estimate of Solutions to the Linearised Curl-Free Compressible Navier–Stokes Equations
Authors: Iwabuchi Tsukasa , Ó hAodha Dáithí
Published: November 2023

We discuss optimal estimates of solutions to the compressible Navier–Stokes equations in Besov norms. In particular, we consider the estimate of the curl-free part of the solution to the linearised equations, in the homogeneous case. We prove that our estimate is optimal in the $$L^\infty $$

L
∞

-norm by showing that the norm is bounded from below by the same decay rate.
Defining an ‘Epidemiological Risk Index’ to analyse COVID-19 mortality across European regions
Authors: Arauzo-Carod Josep-Maria , Giménez-Gómez José-Manuel , Llop Maria
Published: November 2023

The spread and severity of COVID-19 within the European regions have been highly heterogeneous, with significant differences in both the number of infected persons and mortality across regions. This paper improves the weak ability of welfare variables, such as the HDI, to explain COVID-19 mortality. We propose a novel ‘Epidemiological Risk Index’, including environmental quality, global interaction, health system infrastructure, and population characteristics, which provides a better explanation of pandemic mortality in European regions. We deal with spatial interdependence in COVID-19 mortality by using spatial lagged covariates and Geographical Weighted Regressions. The findings in this study call attention to the influence of epidemiological factors in addition to purely development factors in explaining the severity of COVID-19.