bluuebunny/crossref_metadata_2025 huggingface dataset:
The significance of structural rich club hubs for the processing of hierarchical stimuli
Authors: Mecklenbrauck Falko , Gruber Marius , Siestrup Sophie , Zahedi Anoushiravan , Grotegerd Dominik , Mauritz Marco , Trempler Ima , Dannlowski Udo , Schubotz Ricarda I.
Published: December 2023

The brain's structural network follows a hierarchy that is described as rich club (RC) organization, with RC hubs forming the well‐interconnected top of this hierarchy. In this study, we tested whether RC hubs are involved in the processing of hierarchically higher structures in stimulus sequences. Moreover, we explored the role of previously suggested cortical gradients along anterior‐posterior and medial‐lateral axes throughout the frontal cortex. To this end, we conducted a functional magnetic resonance imaging (fMRI) experiment and presented participants with blocks of digit sequences that were structured on different hierarchically nested levels. We additionally collected diffusion weighted imaging data of the same subjects to identify RC hubs. This classification then served as the basis for a region of interest analysis of the fMRI data. Moreover, we determined structural network centrality measures in areas that were found as activation clusters in the whole‐brain fMRI analysis. Our findings support the previously found anterior and medial shift for processing hierarchically higher structures of stimuli. Additionally, we found that the processing of hierarchically higher structures of the stimulus structure engages RC hubs more than for lower levels. Areas involved in the functional processing of hierarchically higher structures were also more likely to be part of the structural RC and were furthermore more central to the structural network. In summary, our results highlight the potential role of the structural RC organization in shaping the cortical processing hierarchy.
Increased white matter fibre dispersion and lower IQ scores in adults born preterm
Authors: Lapidaire Winok , Clayden Jonathan D. , Fewtrell Mary S. , Clark Christopher A.
Published: December 2023

Preterm birth has been associated with altered microstructural properties of the white matter and lower cognitive ability in childhood and adulthood. Due to methodological limitations of the diffusion tensor model, it is not clear whether alterations in myelination or variation in fibre orientation are driving these differences. Novel models applied to multi‐shell diffusion imaging have been used to disentangle these effects, but to date this has not been used to study the preterm brain in adulthood. This study investigated whether novel advanced diffusion MRI metrics such as microscopic anisotropy and orientation dispersion are altered in adults born preterm, and whether this was associated with cognitive performance. Seventy‐two preterm born participants (<37 weeks gestational age) were recruited from a 1982–1984 cohort (33 males, mean age 33.5 ± 1.0 years). Seventy‐two term born (>37 weeks gestational age) controls (34 males, mean age 30.9 ± 4.0 years) were recruited from the general population. Tensor FA was calculated with FSL, while microscopic FA and orientation dispersion entropy (ODE) were estimated using the Spherical Mean Technique (SMT). Estimated Full Scale IQ (FSIQ), Verbal Comprehension Index (VCI) and Perceptual Reasoning Index (PRI) were obtained from the WASI‐II (abbreviated) IQ test. Voxel‐wise comparisons using FSL's tract‐based spatial statistics were performed to test between‐group differences in diffusion MRI metrics as well as within‐group associations of diffusion MRI metrics and IQ outcomes. The preterm group had significantly lower FSIQ, VCI and PRI scores. Preterm subjects demonstrated widespread decreases in ODE reflecting increased fibre dispersion, but no differences in microscopic FA. Tensor FA was increased in a small area in the anterior corona radiata. Lower FA values in the preterm population were associated with lower FSIQ and PRI scores. An increase in fibre dispersion in white matter and lower IQ scores after preterm birth exist in adulthood. Advanced diffusion MRI metrics such as the orientation dispersion entropy can be used to monitor white matter alterations across the lifespan in preterm born individuals. Although not significantly different between preterm and term groups, tensor FA values in the preterm group were associated with cognitive outcome.
CVINet: A deep learning based model for the diagnosis of chronic venous insufficiency in lower extremity using infrared thermal images
Authors: Krishnan Nithyakalyani , Muthu P.
Published: December 2023

Chronic venous insufficiency (CVI) is a venous disorder characterized by impaired blood flow from the lower extremities back to the heart, leading to various symptoms and complications. Accurate and timely diagnosis of CVI is critical for effective management and prevention of further complications. Deep learning (DL) models have shown results that are promising in the field of medical image analysis tasks over the past few years. This article presents CVINet, a enhanced DL‐based convolutional neural network (CNN) model that has been developed specifically for the purpose of diagnosing CVI utilizing thermal imaging data. The proposed CNN model extracts relevant features from input images using a multi‐layered architecture with convolutional layers and pooling layers. Following feature extraction, data are directed to fully connected layers for performing classification task. To enhance the performance of this model, we employ techniques such as dropout regularization and batch normalization. This model utilizes its ability to automatically learn discriminative features from raw thermal images. A large set of thermal images from both CVI patients and healthy individuals was acquired for training and testing of the model. A comparison between few conventional pre‐trained models was conducted, and the best performing model for classification was examined. Pre‐trained VGG‐16, EfficientNet‐B0, and ResNet‐152 models produced classification accuracies of 94.7%, 95.3%, and 95.8%, respectively. The Proposed CVINet model attained a classification accuracy of 96.8% on binary classification, demonstrating high performance compared with other state‐of‐the‐art networks. Overall, our proposed CNN model offers a promising solution for accurately classifying CVI and normal subjects based on thermal images which outperforms the diagnosis by clinician. The potential benefits include early detection of CVI and personalized treatment strategies that can improve patient outcomes. They improve the accuracy of patient diagnosis, reducing radiologist workload and providing them with a tool that can automatically assess the condition of the lower limb venous condition, lowering the risk of misdiagnosis. Furthermore, improving healthcare service quality and early detection can alter the course of the disease and reduce the morbidity and mortality rate of the disease.
Exosomes derived from BMSCs alleviates high glucose‐induced diabetic retinopathy via carrying miR‐483‐5p
Authors: Cao Dan , Zhou Liang , Hu Rong
Published: December 2023

Diabetic retinopathy (DR) is a progressive disease which can cause health problem. It has been reported that bone marrow mesenchymal stem cells (BMSCs)‐secreted exosomes could regulate the progression of DR via carrying microRNAs. Meanwhile, miR‐483‐5p was downregulated in DR; however, whether BMSCs‐secreted exosomes can modulate DR progression via carrying miR‐483‐5p remains unclear. To mimic DR in vitro, ARPE‐19 cells were exposed to 30 mM high glucose (HG). Exosomes were isolated from BMSCs and identified by transmission electron microscopy, nanoparticle tracking analysis, and western blot. Cell counting kit‐8 assay was applied for assessing the cell viability. Flow cytometry was applied to test the cell apoptosis. Meanwhile, dual luciferase assay was used to evaluate the association among miR‐483‐5p and downstream target insulin‐like growth factor 1 receptor (IGF‐1R). In addition, quantitative reverse‐transcription polymerase chain reaction and western blot were used for exploring the level of miR‐483‐5p and IGF‐1R. HG significantly induced apoptosis in ARPE‐19 cells, while BMSCs‐derived exosomes reversed this phenomenon. In addition, inhibition of miR‐483‐5p expression of exosomes further aggravated HG‐induced ARPE‐19 cell apoptosis. Meanwhile, IGF‐1R was the downstream messenger RNA of miR‐483‐5p, and IGF‐1R silencing could reverse the effect of exosomes with downregulated miR‐483‐5p on HG‐induced cell injury. Exosomes derived from BMSCs inhibit the progression of DR via carrying miR‐483‐5p. Thus, our study might provide a theoretical basis for discovering new strategies against DR.
Association of gut microbiota with portal vein pressure in patients with liver cirrhosis undergoing living donor liver transplantation
Authors: Toshida Katsuya , Itoh Shinji , Kosai‐Fujimoto Yukiko , Ishikawa Takuma , Nakayama Yuki , Tsutsui Yuriko , Iseda Norifumi , Izumi Takuma , Bekki Yuki , Yoshiya Shohei , Toshima Takeo , Nakamuta Makoto , Yoshizumi Tomoharu
Published: December 2023

Background and Aim

Many recent studies have shown a relationship between various systemic diseases and the gut microbiota (GM), with the gut–liver axis receiving particular attention. In contrast, no report has comprehensively shown the effects of GM on the pathophysiology of patients undergoing living donor liver transplantation (LDLT).

Method

We enrolled 16 recipients who underwent LDLT for liver cirrhosis, and 17 donors constituted the reference group. We examined the differences in GM between recipients and donors. We also examined the relationships between GM, short‐chain fatty acids, and portal vein pressure (PVP) in recipients.

Results

There was no significant difference in alpha‐diversity between the recipients and donors, but there was variation in beta‐diversity among the recipients. The abundance of the phylum Bacteroidetes was significantly higher in recipients than in donors (P = 0.016), and it was positively correlated with PVP (r = 0.511, P = 0.043). Propionic acid, which is a component of short‐chain fatty acids, was positively correlated with PVP (r = 0.544, P = 0.0295), the phylum Bacteroidetes (r = 0.677, P = 0.004), and total bilirubin concentration (r = 0.501, P = 0.048). Propionic acid was negatively correlated with serum albumin concentration (r = −0.482, P = 0.043).

Conclusion

Our findings suggest relationships between fecal Bacteroidetes levels, propionic acid concentrations, and PVP in patients with liver cirrhosis undergoing LDLT.
Sex differences in the biomechanical and biochemical responses of caudal rat intervertebral discs to injury
Authors: Kenawy Hagar M. , Nuñez María I. , Morales Xóchitl , Lisiewski Lauren E. , Burt Kevin G. , Kim Min Kyu M. , Campos Leonardo , Kiridly Nadia , Hung Clark T. , Chahine Nadeen O.
Published: December 2023

Background

Intervertebral disc degeneration (IDD) is a major cause of low back pain (LBP) worldwide. Sexual dimorphism, or sex‐based differences, appear to exist in the severity of LBP. However, it is unknown if there are sex‐based differences in the inflammatory, biomechanical, biochemical, and histological responses of intervertebral discs (IVDs).

Methods

Caudal (Coccygeal/Co) bone‐disc‐bone motion segments were isolated from multiple spinal levels (Co8 to Co14) of male and female Sprague–Dawley rats. Changes in motion segment biomechanics and extracellular matrix (ECM) biochemistry (glycosaminoglycan [GAG], collagen [COL], water, and DNA content) were evaluated at baseline and in response to chemical insult (lipopolysaccharide [LPS]) or puncture injury ex vivo. We also investigated the contributions of Toll‐like receptor (TLR4) signaling on responses to LPS or puncture injury ex vivo, using a small molecule TLR4 inhibitor, TAK‐242.

Results

Findings indicate that IVD motion segments from female donors had greater nitric oxide (NO) release in LPS groups compared to male donors. HMGB1 release was increased in punctured discs, but not LPS injured discs, with no sex effect. Although both male and female discs exhibited reductions in dynamic moduli in response to LPS and puncture injuries, dynamic moduli from female donors were higher than male donors across all groups. In uninjured (baseline) samples, a significant sex effect was observed in nucleus pulposus (NP) DNA and water content. Female annulus fibrosus (AF) also had higher DNA, GAG, and COL content (normalized by dry weight), but lower water content than male AF. Additional injury‐ and sex‐dependent effects were observed in AF GAG/DNA and COL/DNA content. Finally, TAK‐242 improved the dynamic modulus of female but not male punctured discs.

Conclusions

Our findings demonstrate that there are differences in rat IVD motion segments based on sex, and that the response to injury in inflammatory, biomechanical, biochemical, and histological outcomes also exhibit sex differences. TLR4 inhibition protected against loss of mechanical integrity of puncture‐injured IVD motion segments, with differences responses based on donor sex.
The improvement of routine drug quality control analysis of some antihypertensive drugs using high‐performance thin‐layer chromatography densitometry method with greenness profile evaluation
Authors: Abdelhamid Nessreen S. , Abdelaleem Eglal A. , Lashien Adel , Amin Mahmoud M. , Tohamy Salwa I.
Published: December 2023

The common antihypertensive drugs are B‐blockers and diuretics. For the determination of beta‐blocker medicines (bisoprolol fumarate and carvedilol) and diuretic drug (Furosemide), new and accurate chromatographic method has been developed. The separation was achieved using a developing system that includes chloroform:methanol:ethyl acetate:ammonia (6:2:2:0.2 by volume) as a mobile phase and the bands were detected at 240 nm. The concentration ranges were 5–25, 1–7, and 1–3.5 μg/band for bisoprolol fumarate, carvedilol, and furosemide, respectively. This chromatographic approach is the first methodology for simultaneously determining bisoprolol fumarate, carvedilol, and furosemide in their pure forms and in their pharmaceutical dosage forms. The advantages of using known analytical procedures are their simplicity, speed, cost effectiveness, lack of laboriousness, and ability to save time as the three tablets are determined in one step and can be used for routine analysis of the investigated combinations in quality control laboratories. According to International Conference of Harmonization guidelines, the established procedures have been validated, and the results were statistically compared to those obtained by the reported reversed‐phase–high‐performance liquid chromatography methods using Student's t‐test and F‐test, with no significant difference between them, indicating that the proposed methods can be used for routine drug quality control analysis.
Pharmacokinetics and molecular docking of the cardioprotective flavonoids in Dalbergia odorifera
Authors: Wang Canhong , Gong Bao , Wu Yulan , Bai Congwen , Yang Meihua , Zhao Xiangsheng , Wei Jianhe
Published: December 2023

The purpose of this research was to investigate the cardioprotective effects and pharmacokinetics of Dalbergia odorifera flavonoids. The cardioprotective effects were detected by hematoxylin‐eosin staining histopathological observations and the detection of myocardial enzymes by kits in serum, peroxidation and antioxidant levels and ATPase activities by kits in the homogenate supernatant, and antioxidant and apoptosis‐related protein expression in heart tissue by immunohistochemistry. The pharmacokinetics parameters of the flavonoids in rat plasma were investigated by ultra‐high‐performance liquid chromatography coupled with tandem mass spectrometry. Molecular docking of the compounds absorbed by the blood with specific proteins was carried out. D. odorifera flavonoids significantly reduced the levels of creatinine kinase, alanine transaminase, nitric oxide, and Hydrogen peroxide, elevated the levels of glutathione, superoxide dismutase, and ATPase, significantly reduced the pathological degree of heart tissue and had obvious anti‐myocardial ischemia efficacy. Nine out of the 17 flavonoids were detected in rat plasma. The peak concentration and the area under the plasma concentration‐time curve values of 3′‐O‐methylviolanone and sativanone were significantly higher than those of other ingredients. The peak time of most flavonoids (except for Genistein and Pruneion) was lower than 2 h, while the half‐life of elimination of the nine flavonoids ranged from 3.32 to 21.5 h. The molecular docking results showed that daidzein, dalbergin, formononetin, and genistein had the potential to bind to the target proteins. The results of the study provide an important basis for understanding the cardioprotective effects and clinical application of D. odorifera.
Evaluation of supercritical fluid chromatography coupled to tandem mass spectrometry for the analysis of pesticide residues in grain
Authors: Xie Tingting , Huang Jianli , Wu Jiaqi , Zhang Qingling
Published: December 2023

A supercritical fluid chromatography‐tandem mass spectrometry (SFC‐MS/MS) technique was developed for the rapid and simultaneous detection of nine pesticides (carbendazim, isoprocarb, paclobutrazol, isoprothiolane, flusilazole, quinalphos, piperonylbutoxide, propargite, and bioresmethrin) in rice, wheat, and maize. The cereal samples were extracted with a solution of 0.5% acetic acid in acetonitrile and purified using quick, easy, cheap, effective, rugged, and safe method. The samples were characterized using multi‐reaction monitoring and quantified with the external standard method. Excellent linearities (R2 > 0.9991) and limits of quantification (0.4–40.0 μg/kg) were established for all nine pesticides. Satisfactory pesticide recovery rates (62.2%–107.4%) were obtained at three standard concentrations (50, 100, and 200 μg/kg), with relative standard deviations in the range of 2.1%–14.3%. The results confirmed that the proposed method was suitable for the routine detection of these pesticides in grain samples. Compared with high‐performance liquid chromatography‐MS/MS, the overall test run time and the amount of solvent required were reduced by 66% and 90%, respectively, when SFC‐MS/MS was applied. Therefore, the use of SFC‐MS/MS permits a shorter run time and affords greater analytical efficiency, such that it is both economical and environmentally sustainable.
Phytochemical profiling, in vitro biological activities, and in silico (molecular docking and absorption, distribution, metabolism, excretion, toxicity) studies of Polygonum cognatum Meissn
Authors: Akpınar Reyhan , Yıldırım Baştemur Gizem , Bıçak Bilge , Sanli Nazmiye Ozlem , Mertoğlu Kamalı Elif , Pekmez Murat , Kecel Gündüz Serda , Perçin Özkorucuklu Sabriye
Published: December 2023

Polygonum cognatum Meissn, a perennial herbaceous belonging to the Polygonaceae family, is an aromatic plant. High‐performance liquid chromatography/diode array detector method was developed and validated for the phytochemical analysis of the plant. Also, various methods were used to investigate the antioxidant, antimicrobial, and cytotoxic activities of the methanolic extracts. Antioxidant activities were researched by 2,2′‐diphenyl‐1‐picrylhydrazyl and cupric reducing antioxidant capacity methods. Among the tested standard microbial strains, Candida albicans was found to be more sensitive with a 24.60 ± 0.55 mm inhibition zone according to the diffusion tests. In the microdilution tests, the minimum inhibitory concentration and minimum bactericidal/fungicidal concentration values were 4.75 and ≥ 4.75 mg/mL, respectively, for all tested pathogens. Human colon carcinoma cells were used to investigate cytotoxicity by using 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyl tetrazolium bromide analysis (IC50 = 2891 μg/mL for Plant A, IC50 = 3291 μg/mL for Plant B). Molecular docking and absorption, distribution, metabolism, excretion, and toxicity analysis were used to explain inhibition mechanisms of major phenolic compounds of plants against Tankyrase 1, Tankyrase 2 enzymes, and deoxyribonucleic acid gyrase subunit B and found compatible with experimental results.
Synthesis and characterization of pH‐responsive deep eutectic solvent followed by HPLC for trace determination of bisphenol A in water samples
Authors: Cao Lili , Li Yukaidi
Published: December 2023

A microextraction based on pH‐responsive deep eutectic solvent combined with high‐performance liquid chromatography was developed for the separation, preconcentration, and determination of bisphenol A in water samples. Five deep eutectic solvents were prepared using thymol (hydrogen bond acceptor) and 6‐, 8‐, 9‐, 10‐, and 12‐carbon carboxylic acids (hydrogen bond donor), and were used as extraction solvent. Herein, by alkalinizing the environment, phase transition takes place, and by adding acid, phase separation and extraction of analytes occur simultaneously. Some important parameters on the extraction such as deep eutectic solvent type, molar ratio of deep eutectic solvent components, deep eutectic solvent volume, potassium hydroxide concentration, hydrochloric acid volume, extraction time, and salt addition were optimized. Under the optimum conditions, intra‐ and interday precisions of the method based on seven replicate measurements of 10 μg L–1 of bisphenol A in water samples were 2.2% and 4.3%, respectively. The analytical performance of the method showed linearity over the concentration of 0.05–50 μg L−1 with the detection limit of 0.02 μg L−1. The accuracy of the method was confirmed by spiking different concentrations of bisphenol A in real water samples and obtaining relative recoveries in the range of 92.5%−105.2%.
Current Pediatric Tertiary Care Practices Following Adenotonsillectomy: An Update
Authors: Moroco Annie E. , Friedman Norman , Jabbour Christopher , Roy Soham , Schmidt Richard , Nardone Heather C.
Published: December 2023

Objective

Adenotonsillectomy is a common procedure performed in children, and the practice patterns at academic centers have been evolving with the publication of updated societal guidelines. In this study, we assess perioperative practice patterns at tertiary care children's hospitals for children undergoing adenotonsillectomy.

Methods

A cross‐sectional 18‐question survey distributed in July of 2022 recruited responses through August 25, 2022. The division chiefs of 70 pediatric otolaryngology groups at tertiary care children's hospitals across the United States and Canada were surveyed. Division chiefs submitted survey responses on behalf of the group practice patterns for children undergoing adenotonsillectomy. The main measure was survey responses from the division chiefs of pediatric otolaryngology reporting group practice.

Results

The survey response rate was 46%. Eighty‐eight percent of groups reported an official adenotonsillectomy admission policy. Commonly reported admission criteria included age (93%) and obesity (59%). Eighty‐eight percent of groups defined severe obstructive sleep apnea as apnea‐hypopnea index ≥10. Only 41% of groups required a child to be observed sleeping on room air prior to ambulatory discharge. Ninety‐seven percent of groups reported routinely obtaining preoperative polysomnography in a variety of clinical settings.

Conclusions

Many children's hospitals report an official admission policy following adenotonsillectomy. Despite a decade passing since the initial publication of the American Academy of Otolaryngology–Head and Neck Surgery clinical practice guidelines, there remains great variability in the practice patterns for both preoperative polysomnography and postoperative monitoring and admission. These results highlight an opportunity for an improved unified approach to perioperative pediatric adenotonsillectomy practice.

Level of Evidence

5 Laryngoscope, 134:2931–2936, 2024
Changes in soil quality under long‐term rice‐crayfish farming in the Dongting Lake Plain, China
Authors: Du Linsen , Wang Hua , Zhang Zhen , Xiao Zhihua , Sun Geng , Yu Yelan , Hu Teng
Published: December 2023

Rice‐crayfish (RC) integrated cultivation, as a sustainable agricultural system, could significantly improve soil fertility. However, the soil quality under the long‐term RC farming system is still unclear. To examine the effects of RC cultivation on soil quality in paddy fields, this study utilized an integrated soil quality index (SQI) for examining the soil quality at different soil profiles (0–10, 10–20, and 20–30 cm depth) in rice monoculture (RM) and RC farming systems (after 1, 6, 10, and 15 years) scattered in Nanxian County, Hunan Province, China. The minimum datasets for evaluating soil quality were assembled using the soil pH, bulk density, total nitrogen, microbial biomass carbon, microbial biomass nitrogen, and β‐d‐glucosidase. The findings demonstrated that soil quality was greatly impacted by RC farming, which improved with the increase of years under RC management. The soil quality of 10‐ and 15‐year RC farming systems were significantly higher than RM system. Besides, soil quality declined with increasing soil depth. The SQI value, which may be used as an indicator to assess the soil quality of RC systems, was dominated by total nitrogen, which contributed 27.60% to the SQI value. On the whole, long‐term RC farming affected the soil quality of paddy fields through management methods including non‐rice season flooding, feeding, and no tillage. Through this study, it was found that MDS and SQI composed of appropriate physical, chemical, and biological indicators could more objectively analyze the soil quality of long‐term RC system and provide guidance for sustainable development of RC farming.
Impact of social determinants of health on access to rhinology care and patient outcomes: A pilot study
Authors: Wang Esther , Diaz Ashley , Zhang Douglas , Dimitroyannis Rose , Kim Daniel , Caballero Nadieska , Pinto Jayant M. , Roxbury Christopher R.
Published: December 2023

Objective

This novel pilot study constructs a social deprivation index (SDI) and utilizes an area deprivation index (ADI) to evaluate the link between social determinants of health and rhinology patient experiences.

Methods

Adult patients undergoing outpatient care of chronic rhinitis and chronic rhinosinusitis at a tertiary academic medical center were recruited to participate in a telephone survey assessing symptoms, social/emotional consequences of disease, and barriers to care on a 5‐point Likert scale. Sociodemographic characteristics were utilized to rate SDI on an 8‐point scale. ADI was obtained by area code of residence. Ordered logistic regression was used to examine associations between the SDI/ADI and perceptions of rhinology care.

Results

Fifty patients were included. Individuals with higher SDI scores (i.e., more socially deprived) experienced more severe nasal congestion (p = .007). Furthermore, higher national ADI correlated with increased severity of smell changes (p = .050) and facial pressure (p = .067). No association was seen between either deprivation index and global/psychiatric symptoms. While no correlations were found between higher SDI and difficulties with the costs of prescriptions, rhinologist's visits, or saline, higher SDI was correlated with decreased difficulty with surgery costs (p = .029), and individuals with higher national ADI percentile had increased difficulties obtaining nasal saline (p = .029).

Conclusion

Worse social deprivation is associated with difficulties obtaining saline rinses and increased severity of nasal/sinus symptoms in an urban, underserved, majority‐Black population. These findings suggest social factors affect access to and quality of rhinology care in a complex and nuanced way and highlight the need for a specific SDI to further study social determinants of health in rhinology.

Level of Evidence

2c.
Dual Clay Nanobrick Wall Thin Films with High Oxygen Barrier at High Humidity
Authors: Iverson Ethan T. , Chiang Hsu‐Cheng , Fisher Sarah G. , Legendre Hudson , Schmieg Kendra , Chang Edward , Grunlan Jaime C.
Published: December 2023

Thin polymer‐based coatings with high oxygen barrier at elevated humidity are needed for the protection of food and organic electronic devices. Polyelectrolyte‐based thin films (deposited via layer‐by‐layer assembly) perform well at ambient humidity, but their performance typically dwindles as humidity increases due to their hydrophilic nature. Retention of their high barrier can be achieved through the addition of chemical crosslinkers or the introduction of inorganic platelets that create a nanobrick wall structure. In this study, a nanobrick wall barrier prepared with two types of clay, with a thickness less than 200 nm, is shown to reduce the oxygen transmission rate (OTR) of 179 µm polyethylene terephthalate to less than 0.016 cm3 m−2 day−1 atm−1. At 90% relative humidity (RH), a quadlayer barrier consisting of polyethylenimine, boehmite clay, poly(acrylic acid), and vermiculite clay maintains nearly 90% of its barrier performance at 0% RH (OTR = 0.019 cm3 m−2 day−1 atm−1). This study demonstrates the potential of dual clay thin film nanocomposites to protect various consumer goods at high humidity.
Prevalence and Incidence of Parkinson's Disease in Latin America: A Meta‐Analysis
Authors: Kim Dani J. , Isidro‐Pérez Ana L. , Doering Michelle , Llibre‐Rodriguez Juan J. , Acosta Isaac , Rodriguez Salgado Ana M. , Pinilla‐Monsalve Gabriel D. , Tanner Caroline , Llibre‐Guerra Jorge J. , Prina Matthew
Published: December 2023

Background

Parkinson's disease (PD) is a rapidly growing neurodegenerative disorder, but up‐to‐date epidemiological data are lacking in Latin America. We sought to estimate the prevalence and incidence of PD and parkinsonism in Latin America.

Methods

We searched Medline, Embase, Scopus, Web of Science, Scientific Electronic Library Online, and Literatura Latino‐Americana e do Caribe em Ciências da Saúde or the Latin American and Caribbean Health Science Literature databases for epidemiological studies reporting the prevalence or incidence of PD or parkinsonism in Latin America from their inception to 2022. Quality of studies was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist. Data were pooled via random‐effects meta‐analysis and analyzed by data source (cohort studies or administrative databases), sex, and age group. Significant differences between groups were determined by meta‐regression.

Results

Eighteen studies from 13 Latin American countries were included in the review. Meta‐analyses of 17 studies (nearly 4 million participants) found a prevalence of 472 (95% CI, 271–820) per 100,000 and three studies an incidence of 31 (95% CI, 23–40) per 100,000 person‐years for PD; and seven studies found a prevalence of 4300 (95% CI, 1863–9613) per 100,000 for parkinsonism. The prevalence of PD differed by data source (cohort studies, 733 [95% CI, 427–1255] vs. administrative databases. 114 [95% CI, 63–209] per 100,000,P < 0.01), age group (P < 0.01), but not sex (P = 0.73). PD prevalence in ≥60 years also differed significantly by data source (cohort studies. 1229 [95% CI, 741–2032] vs. administrative databases, 593 [95% CI, 480–733] per 100,000,P < 0.01). Similar patterns were observed for parkinsonism.

Conclusions

The overall prevalence and incidence of PD in Latin America were estimated. PD prevalence differed significantly by the data source and age, but not sex. © 2023 The Authors.Movement Disorderspublished by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Copper micromachined WR‐2.2 band waveguide and bandpass filter
Authors: Shi Guanghua , Wen Xiaozhu , Yang Haodong , Yu Yang , Wang Zhen , Zhang Anxue , Guo Cheng
Published: December 2023

This paper presents a WR‐2.2 band (330–500 GHz) waveguide with E‐plane bends and a waveguide bandpass filter. A micro‐metal additive manufacturing technology employs copper to process these devices. This technology includes several micromachining processes, which can produce integrated, miniaturized, and complex three‐dimensional metal microstructures when meeting the process constraints. To successfully apply this technology to the fabrication of terahertz waveguide devices, many design details are considered. First, the E‐plane bent transition structures in the waveguide overcome size limitations imposed by the manufacturing process, allowing for accurate measurement using standard waveguide interfaces. Second, the rectangular resonators compose the fifth‐order waveguide bandpass filter spanning 20 GHz with a center frequency of 380 GHz. Given that the excess photoresist needs to be removed, some release holes are designed in the proper positions of the filter. Third, to increase the uniformity of the device layout and improve the machining quality in the electroforming process, a lot of rectangular holes are arranged around the device. By adopting a meticulous and novel design method in accordance with the process advantages and limitations, the fabrication accuracy of the device size is greatly increased. The integrated filter with exceptional performance is obtained. The measured average insertion loss within the passband is better than 1.2 dB, and the return loss exceeds 15 dB. Additionally, the filter demonstrates a center frequency offset of approximately 0.5%. Good consistency between simulation and measurement shows the validity of design and fabrication.
Long‐term creep deformation of carbon fiber/epoxy composites with physical aging: Experimental investigation and constitutive modeling
Authors: Yang Jiangyan , Ma Xiaofei , Wang Hui , Shang Fulin , Hou Demen
Published: December 2023

The tensile creep tests for two kinds of epoxy resin matrix composite laminates were performed under 25°C and 50°C. Results indicate that these materials deform in a time‐dependent manner, that is, the tensile strain increases within a short time after the tests began, and then decreases during most of the loading period. Such increase and decrease trends reflect the creep characteristic and effect of physical aging, respectively. A linear viscoelastic model is developed to include both the creep temperature effect and physical aging effect, starting from the Boltzmann superposition principle. In modeling, these two effects both contribute to the transient compliance and result in the increase and decrease of the transient compliance. Time–temperature/aging time superposition principle is adopted to deal with the influences of temperature and physical aging. This theoretical model is further implemented numerically within a finite element framework. To verify the newly proposed model, not only the experimental and numerical results of the tensile deformations of laminates are compared, but also the bending deformations of structural components made from the above laminates are analyzed.

Highlights

Tensile creep tests were done for carbon fiber/epoxy laminates.

The strain shows creep temperature and aging effect (TE and AE).

New constitutive relation was proposed to describe the TE‐ and AE‐caused strains.

Structural‐level flexure creep tests and simulation analyses were conducted.
Through‐thickness tensile characterization and analysis of fiber‐reinforced polymer composites using digital image correlation and finite element modeling
Authors: Ayuso‐Faber P. , Uribe‐Riestra G. , Arana G. , Avilés F.
Published: December 2023

Digital image correlation (DIC) and finite element analysis (FEA) are used to assess the cylindrical spool‐shaped ASTM D7291 and I‐beam‐shaped specimens for through‐thickness (TT) mechanical characterization of thick (~25 mm) fiber reinforced polymer matrix composites. The composites are made of E‐glass woven fabrics reinforcing a vinyl ester matrix. DIC full‐field measurements and FEA showed a rather uniform strain distribution within the gage section of the ASTM D7291 specimen. However, strain concentrations are revealed at the bondlines between the end‐tabs and the test specimen, in addition to strain gradients at the curved section of the specimen. DIC‐measured and FEA‐predicted strain fields of the I‐beam specimens exhibited a region of uniform strain distribution within the gage section larger than that of the ASTM D7291 specimen. Nevertheless, high stress concentrations at the fillet (curved flange‐to‐web transition) regions and some amount of web bending occur in the I‐beam specimen. Beyond providing the TT mechanical properties of the E‐glass woven/vinyl ester composites, the current work discusses advantages and caveats of both promising specimens, providing quantifications of stress concentration factors and length of zones were strains and stresses may be considered uniform.

Highlights

Stress/strain distributions of through‐thickness tensile specimens are evaluated.

The main drawback of the spool‐shaped specimen is adhesive failure.

The modified I‐beam specimen shows acceptable stress concentration factors.

The modified I‐beam is adequate for strength and Poisson ratio characterization.

I‐beam specimens are easier to manufacture and do not require adhesive joints.
Effect of ultraviolet radiation on the low‐velocity impact and compression after impact performances of aerospace composite laminates
Authors: Liu Songjing , Li Zhe , Feng Yu , Zhang Teng , Ma Binlin , Wang Wenqian
Published: December 2023

The low‐velocity impact (LVI) characteristics and compression after impact (CAI) properties of aircraft composite laminates under the influence of ultraviolet (UV) radiation were studied. Firstly, 0, 30, 60, 90 days of UV radiation experiments were carried out on the specimens to analyze the characteristics of the surface topography. Secondly, LVI experiments, the impact energies of 10, 17, and 25 J, were carried out on specimens to analyze the impact response laws and the characteristics of the impact instantaneous deformation. Finally, through CAI experiments and scanning electron microscope (SEM) techniques to clarify the influence mechanism of UV radiation on the residual compressive strength of specimens. The results showed that with the increase of UV radiation time, the shrinkage and erosion phenomena of the surface matrix and the exposure degree of the surface fibers were gradually increased, and the surface fibers were completely exposed after 90 days of radiation. At the same impact energy, with longer radiation time, the peak force gradually decreased (from 8673.86 to 7851.68 N at 17 J), the absorbed impact energy (from 9.48 to 11.13 J at 17 J) and maximum displacement (from 4.1 to 4.73 mm at 17 J) increased, the depth of pit on the impact surface decreased (from 0.213 to 0.14 mm at 17 J), and the internal damage projection area increased (from 906.68 to 1158.66 mm2 at 17 J). The compression damage of the specimens not exposed to/ exposed to UV radiation was mainly fiber cracking/interlayer delamination, respectively.

Highlights

Ultraviolet (UV) radiation makes the matrix of surface shrink, the fibers exposure increase.

The Stage II has obvious oscillation phenomenon in four stages of the low‐velocity impact process.

With prolonged UV radiation, the projected area of internal damage expands.

The residual compressive load increases with the increase of UV radiation time.
On the interlaminar fracture behavior of carbon/epoxy laminates interleaved with fiber‐hybrid non‐woven veils
Authors: Wang S. , Akbolat M. Ç. , Katnam K. B. , Zou Z. , Potluri P. , Taylor J.
Published: December 2023

This study investigates the effect of fiber‐hybrid non‐woven veils on the interlaminar fracture of out‐of‐autoclave carbon/epoxy laminates. The Mode‐I and Mode‐II interlaminar toughening performance and R‐curves behavior of out‐of‐autoclave composite laminates with carbon and thermoplastic fiber‐hybrid veils are investigated. Pure carbon veil (i.e., high‐stiffness fibers), pure polyphenylene sulfide veil (i.e., low‐stiffness fibers), and three variants of fiber‐hybrid carbon/polyphenylene sulfide veil with different fiber contents (i.e., combination of low‐ and high‐ stiffness fibers) are tested and compared for Mode‐I and Mode‐II interlaminar toughening performance. All the pure and fiber‐hybrid non‐woven veils used in this study have a fixed areal density (~20 g/m2). Resin infusion combined with out‐of‐autoclave curing is utilized to manufacture the laminates. The results show that the hybridization of carbon fibers with thermoplastic fibers can address the observed shortcomings of the pure carbon veils (i.e., unstable crack growth) and of the pure thermoplastic veils (i.e., falling R‐curve) in toughening interlaminar regions. Considering both the Mode‐I and Mode‐II interlaminar fracture behavior, it is shown that fiber‐hybrid non‐woven veil toughening offers rising R‐curves, constrained crack paths (inside the veil), and enhanced interlaminar fracture energies, which are desirable for structural applications.

Highlights

Pure carbon/thermoplastic veils have shortcomings in interlaminar toughening.

Hyrid veils constrain crack path and offer rising R‐curve.

The weight ratio of hybrid veils affects crack paths and R‐curves.
A multiplex approach of MS, 1D‐, and 2D‐NMR metabolomics in plant ontogeny: A case study on Clusia minor L. organs (leaf, flower, fruit, and seed)
Authors: Noleto‐Dias Clarice , Farag Mohamed A. , Porzel Andrea , Tavares Josean F. , Wessjohann Ludger A.
Published: December 2023

Introduction

The genus Clusia L. is mostly recognised for the production of prenylated benzophenones and tocotrienol derivatives.

Objectives

The objective of this study was to map metabolome variation within Clusia minor organs at different developmental stages.

Material and Methods

In total 15 organs/stages (leaf, flower, fruit, and seed) were analysed by UPLC‐MS and 1H‐ and heteronuclear multiple‐bond correlation (HMBC)‐NMR‐based metabolomics.

Results

This work led to the assignment of 46 metabolites, belonging to organic acids(1), sugars(2) phenolic acids(1), flavonoids(3) prenylated xanthones(1) benzophenones(4) and tocotrienols(2). Multivariate data analyses explained the variability and classification of samples, highlighting chemical markers that discriminate each organ/stage. Leaves were found to be rich in 5‐hydroxy‐8‐methyltocotrienol (8.5 μg/mg f.w.), while flowers were abundant in the polyprenylated benzophenone nemorosone with maximum level detected in the fully mature flower bud (43 μg/mg f.w.). Nemorosone and 5‐hydroxy tocotrienoloic acid were isolated from FL6 for full structural characterisation. This is the first report of the NMR assignments of 5‐hydroxy tocotrienoloic acid, and its maximum level was detected in the mature fruit at 50 μg/mg f.w. Seeds as typical storage organ were rich in sugars and omega‐6 fatty acids.

Conclusion

To the best of our knowledge, this is the first report on a comparative 1D‐/2D‐NMR approach to assess compositional differences in ontogeny studies compared with LC‐MS exemplified by Clusia organs. Results derived from this study provide better understanding of the stages at which maximal production of natural compounds occur and elucidate in which developmental stages the enzymes responsible for the production of such metabolites are preferentially expressed.
Impact of high‐risk prenatal screening results for 22q11.2 deletion syndrome on obstetric and neonatal management: Secondary analysis from the SMART study
Authors: Martin Kimberly , Norton Mary E. , MacPherson Cora , Demko Zachary , Egbert Melissa , Haeri Sina , Malone Fergal , Wapner Ronald J. , Roman Ashley S. , Khalil Asma , Faro Revital , Madankumar Rajeevi , Strong Noel , Silver Robert , Vohra Nidhi , Hyett Jon , Kao Charlly , Hakonarson Hakon , Jacobson Bo , Dar Pe'er
Published: December 2023

Objective

One goal of prenatal genetic screening is to optimize perinatal care and improve infant outcomes. We sought to determine whether high‐risk cfDNA screening for 22q11.2 deletion syndrome (22q11.2DS) affected prenatal or neonatal management.

Methods

This was a secondary analysis from the SMART study. Patients with high‐risk cfDNA results for 22q11.2DS were compared with the low‐risk cohort for pregnancy characteristics and obstetrical management. To assess differences in neonatal care, we compared high‐risk neonates without prenatal genetic confirmation with a 1:1 matched low‐risk cohort.

Results

Of 18,020 eligible participants enrolled between 2015 and 2019, 38 (0.21%) were high‐risk and 17,982 (99.79%) were low‐risk for 22q11.2DS by cfDNA screening. High‐risk participants had more prenatal diagnostic testing (55.3%; 21/38 vs. 2.0%; 352/17,982, p < 0.001) and fetal echocardiography (76.9%; 10/13 vs. 19.6%; 10/51, p < 0.001). High‐risk newborns without prenatal diagnostic testing had higher rates of neonatal genetic testing (46.2%; 6/13 vs. 0%; 0/51, P < 0.001), echocardiography (30.8%; 4/13 vs. 4.0%; 2/50, p = 0.013), evaluation of calcium levels (46.2%; 6/13 vs. 4.1%; 2/49, P < 0.001) and lymphocyte count (53.8%; 7/13 vs. 15.7%; 8/51, p = 0.008).

Conclusions

High‐risk screening results for 22q11.2DS were associated with higher rates of prenatal and neonatal diagnostic genetic testing and other 22q11.2DS‐specific evaluations. However, these interventions were not universally performed, and >50% of high‐risk infants were discharged without genetic testing, representing possible missed opportunities to improve outcomes for affected individuals.
Study on the lubrication behavior of low molecular weight poly(vinyl chloride‐co‐n‐butyl acrylate‐co‐vinyl acetate) ternary copolymer in rigid PVC
Authors: Song Changtong , Shu Hongyi , Zhang Xianhong , Ma Yuhong , Chen Dong , Yang Wantai
Published: December 2023

Herein, low molecular weight poly(vinyl chloride‐co‐n‐butyl acrylate‐co‐vinyl acetate) (PCBV) ternary copolymers with varied copolymer composition was employed as a novel polymeric lubricant in rigid PVC. The lubrication effect of PCBVs on the melting process and mechanical properties of the final PVC products were fully investigated. The results indicated that PCBV can serve either as an internal or as an external lubricant depending on its composition. PCBV‐45.5 terpolymer (PBA% ~ 45.5%) exhibits outstanding balance both internal and external lubricating roles. SEM‐EDS results show that addition PCBV‐45.5 form a film on the surface of PVC grains as similar as that adding both internal and external lubricants. Fusion characteristics and DMTA demonstrate that PCBV‐45.5 prolongs the fusion time (26% extension, 1.5 phr) and reduces the glass transition temperature (4.0 °C, 1.5 phr). Finally, the mechanical properties of rigid PVC have been greatly improved by using 1.5 phr PCBV‐45.5. In detail, the tensile strength increased from 54 to 59 MPa and the elongation at break increased from 10% to 30%, respectively. Meanwhile, the impact strength of PVC/PCBV‐45.5 is 3.6 times that of the blend without addition. The excellent performance of PCBV exhibited great potential as a polymeric lubricant candidate in rigid PVC composites.