bluuebunny/crossref_metadata_2025 huggingface dataset:
Facile Synthesis and Chiral Resolution of Expanded Helicenes with up to 35 cata‐Fused Benzene Rings**
Authors: Huo Gui‐Fei , Fukunaga Toshiya M. , Hou Xudong , Han Yi , Fan Wei , Wu Shaofei , Isobe Hiroyuki , Wu Jishan
Published: February 2023

Expanded helicenes are expected to show enhanced chiroptical properties as compared to the classical helicenes but the synthesis is very challenging. Herein, we report the facile synthesis of a series of expanded helicenes Hn (n=1–4) containing 11, 19, 27 and 35 cata‐fused benzene rings through Suzuki coupling‐based oligomerization followed by Bi(OTf)3‐mediated regioselective cyclization of vinyl ethers. Their structures were determined by X‐ray crystallographic analysis. Enantiopure H2, H3, and H4 can be isolated by chiral HPLC and they all exhibit strong chiroptical responses with high absorption dissymmetry factor (|gabs|) values (0.020 for H2, 0.021 for H3, and 0.021–0.024 for H4).
Photo‐oxidation of poly(diethylene glycol terephthalate)
Authors: Horne Fiona J. , Liggat John J.
Published: February 2023

The photo‐oxidation of poly(diethylene glycol terephthalate) (PDEGT) under accelerated aging conditions has been investigated. A weatherometer was used to expose samples to simulated sunlight under air, replicating outdoor exposure. Irradiations were also performed under air using UV lamps of wavelengths centred on 302 and 365 nm. After exposure, the extent of degradation was determined using attenuated total reflectance Fourier transform infrared spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy and UV–visible spectroscopy. Results show that in general PDEGT degrades to a greater extent than the closely‐related polymer poly(ethylene terephthalate) due to the susceptibility of the ether linkage. Although the diethylene glycol sequences are not themselves photoactive over this wavelength range and are not acting as photochemical weak links they do serve as additional sites for secondary free radical chemistry.
A new UV‐curable biodegradable waterborne polyurethane‐acrylate based on natural rubber blended with cassava starch
Authors: Tsupphayakorn‐aek Phanthanyaphon , Suwan Anutida , Chaisit Thawanrat , Tulyapitak Tulyapong , Phinyocheep Pranee , Pilard Jean‐Francois , Saetung Nitinart , Saetung Anuwat
Published: February 2023

An ecofriendly UV‐curable biodegradable waterborne polyurethane acrylate (WPUA) was synthesized using hydroxy telechelic natural rubber (HTNR), gelatinized cassava starch (GCS) hexamethylene diisocyanate, hydroxymethyl propionic acid and 2‐hydroxyethyl acrylate and Darocur 1173 (photo‐initiator) for coating, adhesive applications, and so forth. WPUA thus prepared with a total solid content of about 20% had a good storage stability with a pot‐life of 3 months. The UV‐curable WPUA/GCS films showed superior photosensitivity with an irradiation time of 60 s. With increasing GCS content of the WPUA/GCS films, its transparency increased and surface gloss decreased. Scanning electron microscopic micrographs indicated good miscibility with strong interactions between WPUA and GSC in the matrix leading to high tensile strength and surface free energy with enhanced thermal degradation. Increasing the GCS content up to 75 wt% in the film accelerated its degradation under weathering aging, and showed complete disintegration in soil after 7 days. This work provided a new environmentally friendly pathway to prepare WPUA based on HTNR and GCS with good biodegradability.
Sampling technique for Fourier convolution theorem based k‐space filtering
Authors: Ciulla Carlo , Xhaferri Ilva , Deek Fadi P. , Muzhaqi Endri , Veljanovski Dimitar , Shikoska Ustijana Rechkoska , Risteski Filip A.
Published: February 2023

This research presents a sampling technique for Fourier convolution theorem (FCT) based k‐space filtering. One polynomial function and three transfer functions were selected: (1) Gaussian, (2) Bessel, (3) Butterworth, and (4) Chebyshev. The functions were sampled on the image grid, and they are called filtering functions. Each filtering function was multiplied by the Sinc function to obtain the “Sinc‐shaped convolving function.” The k‐space of the Sinc‐shaped convolving function is calculated by direct Fourier transform (FT) and it is featured by a central region. This central region of the k‐space is rectangular in its shape because it is consequential to the direct FT of the product between the filtering function and the Sinc function. Low‐pass and high‐pass filtering is obtained by inverse FT of the pointwise multiplication between the k‐space of the departing image and the k‐space of the Sinc‐shaped convolving function. A variety of cut‐off frequencies, bandwidth, sampling rates, and numbers of poles of the filters were verified as effective to filter the images. Filtering strength can be modified by fine‐tuning the size of the central rectangular k‐space region of the Sinc‐shaped convolving functions. K‐space analysis of departing images and filtered images provide additional evidence of effective filtering. Moreover, k‐space filtering was compared to Z‐space filtering using the extension of the FCT to Z‐space. The novelty of this research is the sampling technique used to determine the Sinc‐shaped convolving function. The sampling technique uses fine‐tuning of bandwidth and sampling rate to determine the strength of the k‐space filter.
Modeling of Magnesium Intercalation into Chevrel Phase Mo6S8: Report on Improved Cell Design
Authors: Drews Janina , Wiedemann Johannes , Maça Alaluf Rudi Ruben , Wang Liping , Blázquez J. Alberto , Zhao‐Karger Zhirong , Fichtner Maximilian , Danner Timo , Latz Arnulf
Published: February 2023

A good understanding of the limiting processes in rechargeable magnesium batteries is key to develop novel high‐capacity/high‐voltage cathode materials. Thereby, the performance of magnesium‐ion batteries can strongly depend on the morphology of the intercalation cathode. Moreover, high mass loadings are essential for commercialization. In this work the influence of different mass loadings are studied in addition to the impact of the particle size distribution of the active material. Therefore, a detailed continuum model is developed, which is able to describe the complex intercalation of magnesium into a Chevrel phase (CP) cathode. The model considers the thermodynamics, kinetics and interplay of the two energetically different intercalation sites of Mo6S8, which results from its unique crystal structure, as well as the impact of the desolvation on the electrochemical reactions and possible ion agglomeration. Ideal combinations of mass loading and electrolyte concentration as well as the desired CP particle size are determined for the state‐of‐the‐art magnesium tetrakis(hexafluoroisopropyloxy)borate Mg[B(hfip)4]2 electrolyte.
Developing dynamic capabilities for the circular economy in the textile and clothing industry in Italy: A natural‐resource‐based view
Authors: Coppola Carla , Vollero Agostino , Siano Alfonso
Published: February 2023

Implementing the circular economy (CE) through the design of a restorative industrial system is a major challenge. This study investigates the capabilities that underpin the circular competitive advantages of firms in the textile and clothing industry in Italy, which is one of the country's most polluting sectors. We have developed a framework of dynamic capabilities needed for circular transition, using the theoretical lenses of a natural‐resource‐based view. Using a multiple‐case study, the strategies of pollution prevention, product stewardship, and sustainable development and the associated capabilities of sensing, seizing, and reconfiguring are investigated. Internal practices, the role of the downstream actors in the supply chain, co‐creation dynamics with external actors, and the social potential of the CE emerge as key factors. Managers may also benefit from our recommendations aimed at increasing the environmental performance of their firms and scaling up their born‐circular businesses.
Ground glass nodules with scattered or eccentric island‐shaped consolidations may have poor outcomes
Authors: Li Ming , Xi Junjie , Zhang Huan , Jin Xing , Fan Zhuoyang , Zhan Cheng , Feng Mingxiang , Tan Lijie , Wang Qun
Published: February 2023

Background

To explore the effect of scattered or eccentric shaped types of ground glass opacity (GGO) on outcomes of patients with solid‐dominant peripheral lung adenocarcinoma.

Methods

We evaluated patients with solid‐dominant peripheral lung adenocarcinoma, who underwent radical surgery at Zhongshan Hospital, Fudan University, between January 2013 and December 2015. Morphologically heterogeneous solid‐dominant lung adenocarcinoma in imaging findings was based on the last preoperative computed tomography (CT) scans. Endpoints were recurrence‐free survival (RFS) and overall survival (OS). Kaplan–Meier analysis and the log‐rank test were used to estimate survival differences. Impact factors were assessed by univariable logistic regression analysis.

Results

We retrospectively collected data from 200 patients, including 170 patients with central island‐shaped CT imaging, 18 patients with scattered shaped CT imaging, and 12 patients with eccentric shaped CT imaging. Eleven patients experienced recurrence or metastases. Kaplan–Meier survival curves showed significant survival differences between the central island‐shaped type and scattered shaped or eccentric shaped type for OS (c‐stage IA: 5‐year OS: 100% vs. 92.1%; HR = 0.019, p = 0.0025; p‐stage IA: 100% vs. 95.2%; HR = 0.146, p = 0.1139) and RFS (c‐stage IA: 5‐year RFS: 100% vs. 59.7%; HR = 0.001, p < 0.0001; p‐stage IA: 100% vs. 64.5%; HR < 0.001, p < 0.0001). Univariable logistic regression analysis showed that scattered and eccentric shaped types were related to poor outcomes (p < 0.012, odds ratio = 18.8).

Conclusions

Relative spatial position of GGO and solid components may affect patient outcomes. Patients with scattered or eccentric shaped GGO may have a poor prognosis.
Therapeutic Potential of Clove Essential Oil in Diabetes: Modulation of Pro‐Inflammatory Mediators, Oxidative Stress and Metabolic Enzyme Activities
Authors: Nait Irahal Imane , Darif Dounia , Guenaou Ismail , Hmimid Fouzia , azzahra Lahlou Fatima , Ez‐zahra Ousaid Fatima , Abdou‐Allah Fatima , Aitsi Lamiaa , Akarid Khadija , Bourhim Noureddine
Published: February 2023

Type 1 diabetes is characterized by insulin deficiency due to the destruction of pancreatic β cells, leading to hyperglycemia, which in turn induces vascular complications. In the current study, we investigated the effect of intraperitoneal administration of clove essential oil (CEO: 20 mg/kg body weight) on certain oxidative stress and glucose metabolism enzymes, as well as the expression of proinflammatory mediators. Administration of CEO to diabetic rats showed a significant decline in blood glucose levels, total cholesterol, and xanthine oxidase, compared to the streptozotocin group. Furthermore, these treated rats elicited a notable attenuation in the levels of lipid peroxides, and thiols groups in both liver and brain tissues. The activities of antioxidant and metabolic enzymes were reverted to normality in diabetic upon CEO administration. In addition to its protective effects on red blood cell hemolysis, CEO is a potent α‐amylase inhibitor with an IC50=298.0±2.75 μg/mL. Also, treatment of diabetic rats with CEO significantly reduced the iNOS expression in the spleen. Our data showed that CEO has potential beneficial effects on diabetes, which can possibly prevent the pathogenesis of diabetic micro‐ and macrovascular complications.
Coping in parenting adolescents with autism spectrum disorder
Authors: Sanchez Genesis , Cragin Casey
Published: February 2023

Coping is defined as the way one thinks and reacts to stressful situations, and the various ways a person may choose to deal with those situations is known as their coping strategies or style (Baqutayan, 2015). While coping is generally regarded as a desirable technique for ensuring one's well‐being, coping styles can be both healthy and unhealthy. When examining the various forms of coping strategies, researchers and clinicians typically use the two basic categories of problem‐focused and emotion‐focused coping. The term problem‐focused coping refers to strategies for resolving an issue that is generating pain by focusing on altering the source(s) of the stress. In contrast, emotion‐focused coping refers to strategies for reducing the negative emotions linked with an issue or stressor. Baqutayan (2015) describes the subcategories of problem‐focused coping as confrontative responding, social support, and planning and the subcategories of emotion‐focused coping as self‐control, seeking social support, distance, positive appraisal, accepting responsibility, and escape/avoidance.
Keep your eye on…
Authors: Knopf Alison
Published: February 2023

Support for eliminating X‐waiver for buprenorphine

New training requirements for prescribers

A call for papers on adolescent mental health
CADCA conference opens with focus on prevention
Authors: Knopf Alison
Published: February 2023

There were 600 young people at the annual leadership conference of CADCA (Community Anti‐Drug Coalitions of America) in January. This meeting fosters primary prevention, i.e., preventing drug and alcohol use before it starts. The young people are very involved in the presentations.
Development of Transition Metal Incorporated Bismuth‐Based Oxide Semiconductors as Potential Candidates for Solar Assisted Water Splitting Applications
Authors: Ghosh Sangeeta , Laha Debajit , Hajra Paramita , Sariket Debasis , Ray Debasish , Baduri Swarnendu , Sahoo Himanshu Sekhar , Bhattacharya Chinmoy
Published: February 2023

Photocatalysis is a traditional approach for solving energy crises and environmental pollution control problems. Visible light‐sensitive transition metal incorporated bismuth‐based metal oxides have enough potential to act as photoelectrodes in the communal of solar energy conversion and environmental remediation. These transition metal incorporated Bi‐based metal oxides are of practical importance due to their efficient photocatalytic activity, high stability, low cost and non‐toxicity. The latest efforts towards the limitations for improvement in performances of these materials can be controlled by different factors e. g., surface morphology, band gap, size, crystallinity, charge separation efficiency and rate of the charge transfer, etc. The alignment of band position or modification of band energy can also play an important role for these materials. Here, we primarily focus on the detailed discussion of transition metal incorporated bismuth‐based oxide semiconductors with suitable modifications – their fabrication and applications to enhance the photoelectrochemical activity.
Conductive Polymer/Graphene‐based Composites for Next Generation Energy Storage and Sensing Applications
Authors: Moyseowicz Adam , Minta Daria , Gryglewicz Grażyna
Published: February 2023

Growing environmental and health demands along with the deficiency of conventional energy sources result in the need for alternative solutions in the field of energy storage and analyte detecting systems. To address these issues, a significant increase in research interest for novel composite materials has been observed in recent years. Conductive polymers and graphene‐based composites have emerged as promising electrode materials for supercapacitors and electrochemical sensors due to their improved electrochemical properties and versatility of the synthesis methods. The synergistic effect between the composite components and the unique morphology, physical and chemical characteristics result in enhanced performance of the electrochemical devices. In this review, we discuss recent trends and achievements in the synthesis, nanoarchitecture, and application of conductive polymers and graphene‐based composites in the field of supercapacitors and electrochemical sensors. Finally, the remaining challenges and future perspectives are discussed. It is believed that this review will provide a current summary and new inspiration for groundbreaking research on advanced electrochemical devices.
The Role of the Transient Atropisomerism and Chirality of Flurbiprofen Unveiled by Laser‐Ablation Rotational Spectroscopy
Authors: Verde Andrés , López Juan Carlos , Blanco Susana
Published: February 2023

The combination of atropisomerism and chirality in flurbiprofen is shown to be relevant concerning its pharmacological activity. The two most stable conformers of a total of eight theoretically predicted for each R‐ or S‐ flurbiprofen enantiomers have been isolated in the cooling conditions of a supersonic jet and structurally characterized by laser ablation Fourier transform microwave spectroscopy. The detected conformers, whose structure is mainly defined by three dihedral angles, only differ in the sign of the phenyl torsion angle giving rise to Sa and Ra atropisomers. A comparison with the structures available for the R‐ and S‐ enantiomers complexed to COX isoforms reveals that the enzymes select only the Sa atropisomers, resulting in a diastereoisomer‐specific recognition. The most stable gas phase conformer is exclusively selected when using the S‐ enantiomer while the second is recognized only for the R‐ enantiomer. These experimental results highlight the importance of atropisomerism in drug design.
Electrochemical Rearrangement for Remote Functionalizations of Unactivated Alkenes
Authors: Wang Dingyi , Yuan Binbin , Xu Jiawei , Ackermann Lutz
Published: February 2023

An electrochemical strategy for the dual functionalizations of unactivated alkenes through an intramolecular migration process was realized in the absence of sacrificial chemical oxidants and noble‐metal catalysts under mild reaction conditions. The electrochemistry enabled a (hetero)aryl migration while providing access to alkenyl/alkynyl‐migration products. Thus, electricity was employed for the formation of functionalized fluoroalkyl radicals through activation of C−H/C−Br bonds from fluorinated esters. Thereby, we obtained a variety of di and mono‐fluorinated alkyl products with good functional group tolerance as well as chemo, and regioselectivities. Likewise, defluorinative allylation of α‐carbonyl alkyl bromides proved viable. The reaction mechanism was established by experiments and computations.
Multi‐task deep neural networks for just‐in‐time software defect prediction on mobile apps
Authors: Huang Qiguo , Li Zhengliang , Gu Qing
Published: February 2023

With the development of smartphones, mobile applications play an irreplaceable role in our daily life, which characteristics often commit code changes to meet new requirements. This characteristic can introduce defects into the software. To provide immediate feedback to developers, previous researchers began to focus on just‐in‐time (JIT) software defect prediction techniques. JIT defect prediction aims to determine whether code commits will introduce defects into the software. It contains two scenarios, within‐project JIT defect prediction and cross‐project JIT defect prediction. Regardless of whether within‐project JIT defect prediction or cross‐project JIT defect prediction all need to have enough labeled data (within‐project JIT defect prediction assumes that have plenty of labeled data from the same project, while cross‐project JIT defect prediction assumes that have sufficient labeled data from source projects). However, in practice, both the source and target projects may only have limited labeled data. We propose the MTL‐DNN method based on multi‐task learning to solve this question. This method contains the data preprocessing layer, input layer, shared layers, task‐specific layers, and output layer. Where the common features of multiple related tasks are learned by sharing layers, and the unique features of each task are learned by the task‐specific layers. For verifying the effectiveness of the MTL‐DNN approach, we evaluate our method on 15 Android mobile apps. The experimental results show that our method significantly outperforms the state‐of‐the‐art single‐task deep learning and classical machine learning methods. This result shows that the MTL‐DNN method can effectively solve the problem of insufficient labeled training data for source and target projects.
A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent teeth
Authors: Mungur Alvin , Chen Haoran , Shahid Saroash , Baysan Aylin
Published: February 2023

Objectives

The objective of this review is to assess the available literature systematically related to the effect of silver diamine fluoride (SDF) for the management of occlusal and root carious lesions in permanent teeth regardless of age.

Materials and Methods

This systematic review was conducted according to the Cochrane Handbook for Systematic Reviews of Interventions and Preferred Reporting Items for Systematic Review and Meta‐Analyses statement. A literature search was performed using PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Web of Science, DOAJ, and Open Gray with no language restrictions up to December 2022. Three reviewers critically assessed the studies for eligibility. Any disputes between the reviewers were handled by a fourth independent reviewer. The quality assessment and data extraction of the studies were performed.

Results

A total of 2176 studies were screened. The titles and abstracts of the studies were then reviewed (n = 346), and 52 studies met the search criteria. Following the full‐text review, 11 studies investigated the effect of SDF against other treatments such as chlorhexidine, sodium fluoride, ammonium bifluoride, tricalcium silicate paste, casein phosphopeptide amorphous calcium phosphate, glass ionomer cement (GIC) combined with fluoride varnish, resin‐modified GIC, and atraumatic restorative treatment were assessed.

Conclusions

Within the limitations of this review, the use of SDF is promising with high preventative fractions in permanent teeth of children and older populations when compared to other topical applications such as dental varnish containing sodium fluoride.
Endoscopic sleeve gastroplasty using the novel single‐channel suturing device: A multicenter experience
Authors: Asokkumar Ravishankar , Ravi Rajesh , Taweerutchana Voraboot , Tan Yu Bin , Maipang Kotchakorn , Hong Lim Chin , Srisuworanan Nicha , Ching Lee Phong , Khor Christopher , Chang Jason , Pausawasdi Nonthalee
Published: February 2023

Background and aim

Endoscopic sleeve gastroplasty (ESG) is an effective treatment for obesity. Recently, a novel single‐channel endoscopic suturing device has been made available to overcome the need for a double‐channel endoscope. However, there is limited evidence evaluating its utility for ESG. In this multicenter study, we aim to assess the efficacy and safety of the single‐channel suturing device for ESG.

Methods

We reviewed the records of 18 patients who underwent ESG using the novel device at the Singapore General Hospital, Singapore, and Siriraj Hospital, Bangkok, between 2020–2021. We adopted a “U” suture pattern. Our primary outcome was to assess technical feasibility and safety. The secondary outcome was to determine the percentage of total body weight loss at 1 year.

Results

The mean ± SD age and body mass index were 42 ± 8.5 years and 34.9 ± 4.4 kg/m2, respectively. The majority were female (61%). ESG was technically successful in 94% (n = 17) of patients. Device dislodgement occurred in one patient. We used an average of five sutures (range, 4–8), and the mean ± SD procedure time was 96.5 ± 43.8 min. No complications occurred. The mean ± SD length of stay was 2.3 ± 1.5 days. The mean ± SD percentage of total body weight loss at 6 and 12 months were 16 ± 5.2% and 13.1 ± 5.8%, respectively. We found that >5%, >10%, and >15% total body weight loss was observed in 83.3%, 72.2%, and 56%, respectively.

Conclusion

ESG using the single‐channel endoscopic suturing system is safe and effective for inducing weight loss at 1 year in patients with obesity.
Pathogenesis of melasma
Authors: Khanna Rayva , Nowah Abigail , Morris Desiree , Desai Seemal R.
Published: February 2023

To adequately guide future therapies, it is important to elucidate the pathogenesis of melasma. Chronic ultraviolet (UV) radiation exposure, hormonal stimulation, and genetic predisposition play a role in melasma. A widely accepted theory for the pathogenesis of melasma is the increase of melanin through UV, which leads to the upregulation of melanin stimulating receptors (MSR) such as melanocortin‐1 receptors (MC1R), resulting in increased hormone binding and melanin production. Furthermore, there are similarities between the histopathologic presentation of melasma and solar elastosis, a hallmark of photo‐aged skin. These overlaps include altered basement membrane, increased vascularization, and increased mast cell count. There is significant data showing greater degree of solar elastosis in the melasma skin compared to the perilesional skin. Additionally, an etiologic factor in the pathogenesis of melasma is hormonal exposure to estrogen. Melasma has increased prevalence among menstruating women, women on oral contraceptives, and pregnant women. In melasma lesions, studies have shown an increased number of estrogen receptors and progesterone receptors in the dermis and epidermis, respectively. Previously, increased melanogenesis was thought to be the sole contributing factor to the pathogenesis of melasma but more recently, aberrant vasodilation and angiogenesis have been found to play a role. Nitric oxide, a potent vasodilator, was found to be overexpressed at the dermal‐epidermal junction and was hypothesized to contribute to melasma through stimulation of tyrosinase and increasing vascularity. In conclusion, the various mechanisms implicated in melasma include melanocyte dysfunction, solar elastosis, mast cell dysfunction, hormonal influence, vascular transformation, and basement membrane damage.
Overlap syndrome of juvenile dermatomyositis with systemic lupus erythematosus: A rare case report of diagnostic perplex
Authors: Belgaumkar Vasudha A. , Raj Rachana , Pradhan Shekhar N. , Bhale Gauri
Published: February 2023

Introduction

Overlap syndromes include a heterogenous group of conditions presenting with mixed features of more than one autoimmune disorder simultaneously in the same patient. Systemic lupus erythematosus (SLE) with myositis overlap is a rare scenario, particularly in the pediatric age group.

Case Details

We describe an adolescent girl presented with photosensitivity, cutaneous ulcers, alopecia, periorbital edema, proximal muscle weakness, and digital gangrene. She was diagnosed as SLE‐juvenile dermatomyositis (DM) overlap based on overlapping clinical features, laboratory markers like anemia, significant proteinuria, hypocomplementemia, raised muscle enzymes, and positivity for antinuclear antibody, dsDNA, and anti‐Ro/anti‐SSA. Prompt treatment with combination of methylprednisolone‐cyclophosphamide pulse led to marked improvement.

Conclusion

Overlap syndromes are challenging in terms of diagnosis and management with unpredictable outcomes and unclear treatment guidelines.
Proteases and microwave treatment on the quality of chitin and chitosan produced from white shrimp (Penaeus vannamei)
Authors: Dong Qiqi , Qiu Weiqiang , Feng Yuhui , Jin Yingshan , Deng Shanggui , Tao Ningping , Jin Yinzhe
Published: February 2023

The aim of this study was to extract chitin and chitosan from shrimp shells by neutral protease‐assisted microwave multiple heating (one, two, three, and four) treatment. The structure and physicochemical properties of chitosan were characterized by scanning electron microscopy (SEM) and Fourier infrared spectroscopy (FTIR). The dielectric properties of chitosan acetate solution were determined by using a PNA‐L network analyzer, and the correlation between chitosan deacetylation degree and dielectric loss was further analyzed. The results show that the degree of deacetylation of chitosan increased from 84.9% to 90.8% with the increase in the number of microwave heating treatments. Furthermore, the chitosan prepared by multiple microwave heating was smoother. The dielectric constant of chitosan solution gradually decreases with the increase of frequency, and the dielectric loss first decreases and then increases. In addition, the dielectric loss of the chitosan solution increased with the degree of deacetylation of chitosan at 2450 MHz (R2 > 0.99). Therefore, enzyme‐assisted microwave extraction of chitosan can be used to obtain high‐quality chitosan under the condition of increasing the number of heating treatments.
Utility of fractional excretion of urea nitrogen in heart failure patients with chronic kidney disease
Authors: Watanabe Yukihiro , Kubota Yoshiaki , Nishino Takuya , Tara Shuhei , Kato Katsuhito , Hayashi Daisuke , Mozawa Kosuke , Matsuda Junya , Tokita Yukichi , Yasutake Masahiro , Asai Kuniya , Iwasaki Yu‐ki
Published: February 2023

Aims

Maintenance of euvolaemia with diuretics is critical in heart failure (HF) patients with chronic kidney disease (CKD); however, it is challenging because no reliable marker of volume status exists. Fractional excretion of urea nitrogen (FEUN) is a useful index of volume status in patients with renal failure. We aimed to examine whether FEUN is a surrogate marker of volume status for risk stratification in HF patients with CKD.

Methods and results

We examined 516 HF patients with CKD (defined as discharge estimated glomerular filtration rate < 60 mL/min/1.73 m2) whose FEUN was measured at discharge (median age, 80 years; 58% male). The patients were divided into four groups according to quartile FEUN value at discharge: low‐FEUN, FEUN ≤ 32.1; medium‐FEUN, 32.1 < FEUN ≤ 38.0; high‐FEUN, 38.0 < FEUN ≤ 43.7; and extremely‐high‐FEUN, FEUN > 43.7. FEUN was calculated by the following formula: (urinary urea × serum creatinine) × 100/(serum urea × urinary creatinine). During the 3 year follow‐up, 131 HF readmissions occurred. Kaplan–Meier analysis showed that the HF readmission rate was significantly lower in the medium‐FEUN group than in the other three groups (log‐rank test, P = 0.029). Multivariate Cox regression analysis identified the low‐FEUN, high‐FEUN, and extremely‐high‐FEUN values as independent factors associated with post‐discharge HF readmission. In the analysis of 130 patients who underwent right heart catheterization during hospitalization, a significant correlation between FEUN value and right atrial pressure was observed (R = 0.243, P = 0.005). Multivariate linear regression analysis revealed that FEUN value at discharge decreased in a dose‐dependent manner with loop diuretics.

Conclusions

In HF patients with CKD, FEUN is a potential marker of volume status for risk stratification of post‐discharge HF readmission. Low FEUN value (FEUN ≤ 32.1) may represent intravascular dehydration, whereas high FEUN value (FEUN > 38.0) may represent residual congestion; both of them were independent risk factors for HF readmission. FEUN may be useful to determine euvolaemia and guide fluid management in HF patients with CKD.
Oxovanadium(V)‐Catalyzed Deoxygenative Coupling Reaction of Alcohols with Trimethylsilyl Enol Ethers in the Presence of MS3A
Authors: Matsutani Takanari , Sakuramoto Takashi , Okabayashi Kento , Tobisu Mamoru , Moriuchi Toshiyuki
Published: February 2023

Oxovanadium(V)‐catalyzed deoxygenative coupling reaction of allyl alcohols with trimethylsilyl enol ethers was demonstrated to afford γ,δ‐unsaturated carbonyl compounds in one‐step. The catalytic deoxygenative coupling reaction of allyl alcohols proceeded smoothly with both aromatic and aliphatic trimethylsilyl enol ethers. This catalytic deoxygenative coupling system could be applied to the deoxygenative coupling reaction of benzyl alcohols with trimethylsilyl enol ethers, providing the corresponding carbonyl compounds. Furthermore, a gram‐scale catalytic synthesis of the γ,δ‐unsaturated carbonyl compound was successfully performed to validate the scalability of this catalytic deoxygenative coupling reaction.
Synthesis, Structural Characterization, and Reductive Cleavage of an Oxygen‐Containing Naphthyl Macrocycle
Authors: Zhou Zheng , Pennachio Matthew , Wei Zheng , Heldner Maxi L. , Petrukhina Marina A. , Schaub Tobias A.
Published: February 2023

A small macrocycle comprising ether‐bridged naphthyl units was prepared in a two‐step synthesis. Single‐crystal X‐ray diffraction of two polymorphs are reported, one of which showed multiple C−H⋅⋅⋅πnaphthyl interactions of a solvent molecule in the cavity of the macrocycle. Chemical reduction led to C−O bond cleavages accompanied by a Z/E isomerization. The resulting twofold negatively charged (E)‐1,2‐bis(2‐naphthyl)ethylene fragment was isolated as its potassium salts. Electronic characterization revealed a singlet ground state, and a marked distortion of the central ethylene unit was observed upon electron uptake.
Seismic displacement of earth slopes incorporating co‐seismic accumulation of dynamic pore water pressure
Authors: Ji Jian , Zhang Wenliang , Zhang Tong , Song Jian
Published: February 2023

The earthquake‐induced displacement of sloping soil mass is an important indicator of co‐seismic landslide initiation. In this paper, an improved Newmark displacement model that considers the accumulation of dynamic pore water pressure (DPWP) in the soil caused by both vertical and horizontal ground motions is proposed. The model can quantitatively describe the dynamic changes of the seismic yield acceleration of near‐saturated infinite soil slopes. Three different types of ground motion time histories are selected to compare the performance of the proposed Newmark displacement model, and the influence of DPWP accumulation on the slope yield acceleration and on the seismic displacement is obtained. The seismic slope displacement analyses indicate that the weakening effect of slope yield acceleration caused by bidirectional earthquake excitation‐induced DPWP is more obvious than when only considering the horizontal ground motion, when the slip surface soils are in near‐saturated state. The effect of initial saturation (Sr0) on the DPWP accumulation caused by vertical ground motion is also investigated. Furthermore, the accumulated seismic displacement can be reasonably explained by the frequency distribution characteristics of the ground motions. Finally, the numerical results of this paper show that the seismic displacement model seldomly considering the effect of DPWP, or only considering the DPWP induced by horizontal ground motion, can significantly underestimate the displacement value when the slip surface soils are in a near‐saturated state.
Effect of membrane deposition methods on the performance of membrane electrode assemblies
Authors: Xing Yijing , Liu Lei , Li Zhuoqun , Li Yifan , Fu Zhiyong , Li Haibin
Published: February 2023

The performance of proton exchange membrane fuel cells (PEMFCs) is closely related to the preparation process of the membrane electrode assemblies (MEAs). The direct membrane deposition approach can achieve excellent interfacial connection between functional layer, as well as simplifying the MEA manufacturing process. Nevertheless, it has been recognized that for this approach, the permeation of the electrolyte solution into the catalyst layer is a challenge, and it is associated with the deposition method. In this study, three MEAs are prepared by spraying, blade coating, and a combination of the two. The effect of the electrolyte solution deposition methods on the properties of the MEAs is analyzed. The MEA prepared using the combination of spraying and blade coating delivers the highest performance of up to 0.618 W cm−2 (80°C with H2/air conditions at normal pressure). In this method, the spraying layer can alleviate the negative effect of cracks on the gas diffusion electrode surface, and the blade‐coating layer can improve the membrane uniformity. The MEA prepared by this method exhibits excellent cell performance compared to the traditional catalyst coated membrane type MEA, particularly in low‐humidity conditions. This work provides guidance for the preparation of high‐performance MEAs for PEMFCs.
Assessing knowledge of sickle cell disease and health beliefs on premarital genetic screening among healthcare trainees at a tertiary institution: A cross‐sectional study
Authors: Agbozo William Kwaku , Amanor Ernest , Acheampong Eugene Owusu , Kotei Brenda , Attoh Leslie Nii , Yeboah David , Odonkor Prince , Obiri Seth , Kwarteng Alexander , Larbi Amma
Published: February 2023

Background

The uptake of sickle cell trait (SCT) test is challenged by several factors. A community of healthcare professionals educating the public to undergo screening is critical in reducing the disease burden. We investigated knowledge and attitude towards premarital SCT screening among healthcare trainee students who are the next generation of healthcare practitioners.

Methods

A cross‐sectional design was employed, and quantitative data were collected from 451 female students pursuing healthcare programs at a tertiary institution in Ghana. Descriptive, bivariate, and multivariate logistic regression analysis was performed.

Results

More than half of the participants were 20–24 years (54.55%) and had good knowledge (71.18%) about sickle cell disease (SCD). Age and school or social media as sources of information were significantly associated with good knowledge about SCD. Students between the age 20–24 (adjusted odds ratio [AOR] = 2.54, confidence interval [CI] = 1.30–4.97) and knowledge (AOR = 2.19, CI = 1.41–3.39) were 3 times and 2 times more likely to have a positive perception about SCD severity. Students who have SCT (AOR = 5.16, CI = 2.46–10.82), whose source of information was family member/friends (AOR = 2.83, CI = 1.44–5.59) and social media (AOR = 4.59, CI = 2.09–10.12) were 5 times, 2 times and 5 times likely to have a positive perception about the susceptibility of SCD. Students whose source of information is school (AOR = 2.06, CI = 1.11–3.81) and who have good knowledge of SCD (AOR = 2.25, CI = 1.44–3.52) were 2 times more likely to have a positive perception about the benefits of testing. Students with SCT (AOR = 2.64, CI = 1.36–5.13) and source of information was social media (AOR = 3.01, CI = 1.36–6.64) were about 3 times more likely to have a positive perception about the barriers to testing.

Conclusion

Our data shows that high level of SCD knowledge influences positive perceptions about the severity of SCD, the benefits and relatively low barriers to SCT or SCD testing and genetic counseling. Dissemination of SCT, SCD and premarital genetic counseling education should be intensified especially in schools.
Characteristic time scales of evaporation from a subarctic reservoir
Authors: Pierre Adrien , Nadeau Daniel F. , Thiboult Antoine , Rousseau Alain N. , Tremblay Alain , Isabelle Pierre‐Erik , Anctil François
Published: February 2023

Water bodies such as lakes and reservoirs affect the regional climate by acting as heat sinks and sources through the evaporation of substantial quantities of water over several months of the year. Unfortunately, energy exchange observations between deep reservoirs and the atmosphere remain rare in northeastern North America, which has one of the highest densities of water bodies in the world. This study characterizes the dynamics of turbulent heat fluxes by analysing in‐situ observations of a compact and dimictic reservoir (50.69° N, 63.24° W) located in a subarctic environment. The reservoir is characterized by a mean depth of 44 m and a surface area of 85 km2. Two eddy covariance (EC) systems, one on a raft and one onshore, were deployed from 27 June 2018 to 12 June 2022. The thermal regime of the reservoir was monitored using two vertical chains of thermistors. Results indicate a mean annual evaporation rate of 590 ± 66 mm, which is equivalent to ≈51% of the annual precipitation, with 84% of the evaporation occurring at a high rate from August to freeze‐up in late December through episodic pulses. It was difficult to close the energy balance because of the magnitude and the large time lag of the heat storage term. To circumvent this problem, we opted to perform calculations for a year that started from the first of March, as the heat storage in the water column was at its lowest at that point and could thus be ignored. From June to December, monthly Bowen ratios increased from near‐zero negative values to about 1.5. After September, due to smaller vapour pressure deficits, latent heat fluxes steadily decreased until the reservoir had a complete ice cover. Opposite diurnal cycles of sensible and latent heat fluxes were revealed during the open water period, with sensible heat fluxes peaking at night and latent heat fluxes peaking in the afternoon.
Study on the quality difference of Cyperus rotundus before and after vinegar processing based on ultra‐high‐performance liquid chromatography‐quadrupole‐time of flight‐mass spectrometry and molecular network combined with color parameters
Authors: Shi Yabo , Mei Xi , Li Yu , Li Mingxuan , Ji De , Su Lianlin , Mao Chunqin , Lu Tulin
Published: February 2023

Cyperus rotundus is the dry rhizome of the Cyperaceae plant Cyperus. Although there are two types of processed products in clinics, their quality differences are not clear, and the identification methods are more complex. In this study, the chemical composition of different processed products of Cyperus rotundus was characterized using ultra‐high‐performance liquid chromatography‐quadrupole‐time of flight‐mass spectrometry and molecular network analysis, to identify the potential chemical markers and to establish a quick and simple color‐based discrimination method. Among the 65 compounds analyzed, 12 showed significant differences. Observing the color, the surface brightness (L*) of Cyperus rotundus decreased after vinegar processing, while red (a*) and yellow (b*) values increased. These color values correlated significantly with chemical compositions. Finally, a color discriminant function was established and verified for raw Cyperus rotundus and vinegar‐processing Cyperus rotundus. Based on this study, Cyperus rotundus' quality can be effectively controlled and provides a method for the comprehensive characterization of chemical components and chemical markers of other traditional Chinese medicine and processed products, as well as new ideas and methods in identification and quality evaluation.
Stereo Jones Matrix Holography with Longitudinal Polarization Transformation
Authors: Zhao Ruizhe , Wei Qunshuo , Li Yuzhao , Li Xin , Geng Guangzhou , Li Xiaowei , Li Junjie , Wang Yongtian , Huang Lingling
Published: February 2023

Metasurfaces have exhibited powerful abilities for manipulating multiple fundamental properties of light including amplitude, phase, polarization, and so on. However, these strategies are commonly concentrated on the modulations at a single transverse plane of output light. The spatial evolutions of these properties, especially the polarizations along longitudinal direction, are rarely investigated. Here, a stereo Jones matrix holography method is presented for understanding the spatial evolution including polarization, amplitude, and phase variations along the longitudinal direction. Stereo holographic algorithms in matrix framework are developed to generate multiplane and even continuously varied vectorial holographic images that exhibit distinct polarization states at each transverse plane. This method provides a benchmark of longitudinal polarization transformations as well as beam modulations by simply using a single planar metasurface without extra burdens on optical path. In addition, the obtained propagation‐dependent features can favor the realizing of on‐demand transverse and longitudinal spatial evolution from the perspective of the holographic method. Furthermore, it may also promote the development of related areas including polarization‐switchable devices, optical trapping, microscopy, laser processing, etc.
Preparation and Characterization of Silver Nanoparticles (AgNPs) by Pulsed Laser Ablation in Liquid
Authors: Abdulraheem Israa M. , Khodair Ziad T. , Habeeb Ammar A.
Published: February 2023

In this study, the technique of pulsed laser ablation in liquid (PLAL) is used to prepare colloidal silver (Ag) nanoparticles in distilled water (D.W.). The optical properties and the synthesis of the nanoparticles are characterized by UV‐visible spectrophotometer, photoluminescence (PL), infrared Fourier transforms (FT‐IR), and transmission electron microscopy (TEM) measurement. The optical characteristics of (Ag) nanoparticles are investigated using (UV–vis) analysis on all colloidal samples, which reveal a large peak at wavelengths of (405–410 nm) for silver nanoparticles created using PLAL technology. The infrared Fourier transforms (FT‐IR) study determines the functional groups of silver nanoparticles in D.W. The silver nanoparticles (AgNPs) have a spherical form, and their diameters range from 12 to 20 nm, according to the transmission electron microscopy (TEM) measurements. The photoluminescence (PL) data reveal two peaks, one in the visible region, which is responsible for the production of silver nanoparticles, and the other in the UV region, where the size of the nanoparticles grows as the number of laser pulses increases.
A comparative Assessment of Aspergillus niger and Fusarium pallidoroseum for Synthesizing Metal‐Nanoparticles of Zinc and Silver
Authors: Shukla Gyanika , Singh Amardeep , Gaurav Shailendra Singh , Rani Poonam
Published: February 2023

The present study is carried to establish and compare the mycogenic silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnONPs) synthesizing ability of two fungi, Aspergillus niger and Fusarium pallidoroseum. A 2 mM solution of silver nitrate and zinc nitrate hexahydrate is used as the precursor solution for the synthesis of silver and zinc oxide nanoparticles respectively using 1 g and 100 mg fungal biomass per 100 mL of the precursor solution. The synthesis of nanoparticles is preliminarily confirmed by UV–Vis Spectroscopy and further characterization is done through the Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X‐Ray (EDX), Dynamic Light Scattering (DLS), Fourier Transform Infra‐Red (FTIR), and Inductively Coupled Plasma Mass Spectrometry (ICPMS) to characterize the nanoparticles in terms of shape, size, and concentration. The particles synthesized by using 100 mg fungal biomass are much agglomerated and bulky in size. The study concludes that 1 g F. pallidoroseum biomass showed much efficacy toward synthesizing fine‐sized ZnONPs as compared to A. niger, whereas, although the AgNPs synthesized by A. niger are more monodispersed with least agglomeration, the efficacy of A. niger and F. pallidoroseum is found to be mostly comparable in synthesizing AgNPs.
Role of Surfactants Against Covid‐19: A Scientific Approach
Authors: Tripathy Divya Bajpai , Bhati Kajol , Gupta Anjali
Published: February 2023

Pandemic emerged due to the spread of SARS‐COV‐2 has become a most serious problem faced by today's world. Even after about 8 months, neither there is any decrease in its magnitude or in the spread. In some countries, it has reached the peak of its horrors, while some countries are still forced to guess only what will be the peak maxima of number of Covid‐19 patients. People are compelled to maintain social distancing, cleanliness, and high level of hygiene. Right from the beginning of this epidemic, it has been concluded that washing hands every hour with soap (surfactants) can help people to protect themselves from this disease. Surfactants can play a major role in stopping the spread of this epidemic? In this review article, the role of surfactants to stop the spread of Covid‐19 has been discussed. In addition, some of the other prospects of surfactants in Covid‐19 such as a drug delivery of pulmonary drugs have also been explained.