bluuebunny/crossref_metadata_2025 huggingface dataset:
The Inhibitory Activity of Natural Products to Xanthine Oxidase
Authors: Zhou Shiyang , Huang Gangliang
Published: April 2023

The natural products have a new chemical structure and biological active diversity, so they are favored by scientific researchers. Gout is a high incidence and high‐risk disease, and the current treatments are not satisfactory. Xanthine oxidase (XO) is a key enzyme responsible for the development and progression of various metabolic and oxidative stress‐related diseases. Excessive activity of XO leads to elevated serum urate levels, which in turn leads to the development of hyperuricemia. This review mainly introduces the recent progress of the new research on the anti‐gout activity of natural products that could provide new treatment methods for gout and information for the discovery and development of new anti‐gout drugs.
Dose‐Dependent Dual Effect ofMorus nigraL. Extract on Urinary Parameters of Hypertensive Rats
Authors: Bolda Mariano Luísa Nathália , Cechinel‐Zanchett Camile Cecconi , Nazário Daniela , Lupatini Keila , de Souza Priscila
Published: April 2023

This study investigated the diuretic and antiurolithic effects of the hydroalcoholic extract obtained fromMorus nigraL. leaves (HEMN) in female hypertensive rats. The rats were treated orally with vehicle (VEH), hydrochlorothiazide (HCTZ), or HEMN. After 8 h, the urine was analyzed. Besides, the precipitation of calcium oxalate (CaOx) was induced in the urine. The HEMN, at a dose of 0.03 mg/g, increased the volume of urine compared to the VEH‐treated group and increased the urinary content of Cl−, without altering the excretion of Na+and K+. Besides, HENM reduced the elimination of Ca2+in the urine. On the other hand, at a dose of 0.1 mg/g, it significantly reduced the volume of urine excreted, thus suggesting an antidiuretic effect dependent on the dose used. Similarly, HEMN at concentrations of 1 and 3 mg/mL reduced CaOx crystals′ formation in monohydrate and dihydrate forms. However, with the increase in the concentration of HEMN to 10 mg/mL, a significant increase in the formation of CaOx crystals was found. In conclusion,M. nigraextract has a dose‐dependent dual effect on urinary parameters, which may have a diuretic and antiurolithic effect at lower doses or the opposite effect at higher doses.
Essential Oils of Ferulago glareosa Kandemir&Hedge Roots and Aerial Parts: PCA and HCA Analyses
Authors: Kılıç Ceyda S. , Demirci Betül , Kırcı Damla , Duman Hayri , Gürbüz İlhan
Published: April 2023

Ferulago glareosa Kandemir & Hedge. is an endemic species of the family Apiaceae for Turkey and has interesting morphological characteristics compared to the other members of the genus Ferulago Koch. In this study we investigated the essential oil compositions of the roots and aerial parts of F. glareosa for the first time and compared them with essential oil compositions of the roots and aerial parts of other species of the genus. In our study, major components of the essential oil of the roots were determined to be 2,3,6‐trimethylbenzaldehyde (32.2 %), falcarinol (23.7 %), hexadecanoic acid (9.5 %) and 2,5‐dimethoxy‐p‐cymene (5.9 %); and major components of the essential oil of the aerial parts were found to be α‐pinene (33.7 %), p‐cymene (14.8 %), γ‐terpinene (13.2 %), (Z)‐β‐ocimene (12.4 %) and terpinolene (8.2 %). The essential oil compositions of F. glareosa root compare with essential oils components in the literature differ varies greatly. Hierarchical Cluster Analysis (HCA) was performed with Minitab software, utilizing 8 major components in the published 20 literatures, as well as in this study. Principal Component Analyses (PCA) were used in order to demonstrate chemotaxonomical variations in the composition of the essential oils of Ferulago species.
Electroreductive Cross‐Electrophile Coupling of Aziridines and Aryl Bromides
Authors: Yang Guoqing , Wang Yanwei , Qiu Youai
Published: April 2023

Herein, a nickela‐electrocatalyzed cross‐electrophile coupling of readily available aryl aziridines and aryl bromides under mild and sustainable electrochemical conditions to access synthetic useful β‐arylethylamines is developed. This protocol is characterized by its exquisite chemo‐ and regioselectivity, broad substrate scope and good functional group compatibility. Mechanistic studies confirmed that the regioselectivity and reactivity observed are a result of electro‐induced ring‐opening of aziridines under electroreductive conditions to generate a benzyl radical intermediate as the active species. Furthermore, this strategy also enables cross‐coupling with CO2 to access β‐amino acids under mild conditions.
Late‐Stage Functionalization for the Divergent Synthesis of Podophyllotoxin Derivatives by Rhodium Catalysis
Authors: Zhao Yue , Shen Yangpeng , He Jian , Li Jing , Zhou Shengbin , Wang Yunbo , Li Chunpu , Liu Hong
Published: April 2023

A divergent synthesis of podophyllotoxin derivatives from simple and readily available starting materials through a late‐stage functionalization strategy by rhodium catalysis is reported here. This strategy uses the ketone and oxime in substrates as directing groups. Four kinds of novel podophyllotoxin derivatives have been obtained without any erosion of the enantiopurity, thus indicating the broad substrate scope of this method. Additionally, by using the newly developed strategy, 9 aa, which exhibited excellent anticancer activity, can be prepared by a sequential transformation. In particularly, 9 aa suppressed HeLa cells with IC50 values of 74.5 nM, thus providing a promising lead compound for future drug discovery.
An Active Member of the EFMC: The Division of Medicinal Chemistry and Chemical Biology of the Swiss Chemical Society**
Authors: Auberson Yves P. , Benfatti Fides , Gillingham Dennis , Hartrampf Nina
Published: April 2023

The Division of Medicinal Chemistry and Chemical Biology (DMCCB) of the Swiss Chemical Society is an active contributor to the dynamics of the Swiss and European scientific communities. Founded in 1987, it pursues its mission to foster relationships among its academic and industrial members, to facilitate exchange by organizing symposia and courses, and to encourage scientific excellence. This article presents the DMCCB and highlights both its offer to the community and its participation in the activities of EFMC, the European Federation for Medicinal chemistry and Chemical biology.
3D atlas of cerebral neuropils with previously unknown demarcations in the honey bee brain
Authors: Habenstein Jens , Grübel Kornelia , Pfeiffer Keram , Rössler Wolfgang
Published: April 2023

Honey bees (Apis mellifera) express remarkable social interactions and cognitive capabilities that have been studied extensively. In many cases, behavioral studies were accompanied by neurophysiological and neuroanatomical investigations. While most studies have focused on primary sensory neuropils, such as the optic lobes or antennal lobes, and major integration centers, such as the mushroom bodies or the central complex, many regions of the cerebrum (the central brain without the optic lobes) of the honey bee are only poorly explored so far, both anatomically and physiologically. To promote studies of these brain regions, we used anti‐synapsin immunolabeling and neuronal tract tracings followed by confocal imaging and 3D reconstructions to demarcate all neuropils in the honey bee cerebrum and close this gap at the anatomical level. We demarcated 35 neuropils and 25 fiber tracts in the honey bee cerebrum, most of which have counterparts in the fly (Drosophila melanogaster) and other insect species that have been investigated so far at this level of detail. We discuss the role of cerebral neuropils in multisensory integration in the insect brain, emphasize the importance of this brain atlas for comparative studies, and highlight specific architectural features of the honey bee cerebrum.
On a finite strain modeling of growth in budding yeast
Authors: Awada Zeinab , Nedjar Boumediene
Published: April 2023

Cell's ability to proliferate constitutes one of the most defining features of life. The proliferation occurs through a succession of events; the cell cycle, whereby the cell grows and divides. In this paper, focus is made on the growth step and we deal specifically with Saccharomyces cerevisiae yeast that reproduces by budding. For this, we develop a theoretical model to predict the growth powered by the turgor pressure. This cell is herein considered as a thin‐walled structure with almost axisymmetrical shape. Due to its soft nature, the large deformation range is a priori assumed through a finite growth modeling framework. The used kinematics is based on the multiplicative decomposition of the deformation gradient into an elastically reversible part and a growth part. Constitutive equations are proposed where use is made of hyperelasticity together with a local evolution equation, this latter to describe the way growth takes place. In particular, two essential parameters are involved: a stress‐like threshold, and a characteristic time. The developed model is extended to a shell approach as well. In a finite element context, representative numerical simulations examining stress‐dependent growth are given and a parametric study is conducted to show the sensitivity with respect to the above mentioned parameters. Finally, a suggestion for natural contractile ring modeling closes this study.
Cerebrospinal fluid‐dissemination of a ovarian clear cell carcinoma: A leptomeningial carcinomatosis with diagnostic challenges
Authors: Koyuncuer Ali , Varol Eyup , Serarslan Yağcioğlu Bengül , Bükte Yaşar , Sakcı Zakir
Published: April 2023

Metastases from ovarian cancer to the central nervous system (CNS) are rare, in particular, isolated leptomeningeal metastases (LM) are extremely rare. The gold standard in the diagnosis of leptomeningeal carcinomatosis (LC) is the detection of malignant cells in cerebrospinal fluid (CSF) cytology. A 58‐year‐old woman diagnosed with ovarian cancer 2 years ago underwent lumbar puncture and CSF cytology in recent months due to new weakness, loss of strength in the lower extremities, and speech disorders. Magnetic resonance imaging CNS was simultaneously visualized and linear leptomeningeal enhancement was demonstrated. CSF cytology showed tumor cells as isolated cells or small clusters of tumor cells with large, partially vacuolated, and abundant cytoplasm, mostly with centrally located nuclei. Given her history of high‐grade clear cell ovarian cancer,CSF cytology was positive for malignant cells and a diagnosis of leptomeningeal carcinomatosis was made by the neuro‐oncology multidisciplinary tumor board. Since LM also implies a systemic disease, the prognosis is very poor, CSF cytology will play an important role in rapid diagnosis and will be useful both in the right choice of treatment and in the early initiation of palliative care.
Children's shyness and physiological arousal to a peer's social stress
Authors: Poole Kristie L. , Sosa‐Hernandez Linda , Green Emma S. , Wilson McLennon , Labahn Claudia , Henderson Heather A.
Published: April 2023

Previous work has shown that children's shyness is related to personal anxiety during social stress, but we know little about how shyness is related to anxiety during a peer's social stress. Children (Mage = 10.22 years, SD = 0.81, N = 62) were paired with an unfamiliar peer and engaged in a speech task while electrocardiography was recorded. We modeled changes in children's heart rate, a physiological correlate of anxiety, while they observed their peer prepare and deliver a speech. Results revealed that the observing child's shyness related to increases in their heart rate during their peer's preparation period, but modulation of this arousal was sensitive to the presenting peer's anxious behavior while delivering their speech. Specifically, if the presenting child displayed high levels of anxious behavior, the observing child's shyness was related to further increases in heart rate, but if the presenting child displayed low levels of anxious behavior, the observing child's shyness was related to decreases in heart rate from the preparation period. Shy children may experience physiological arousal to a peer's social stress but can regulate this arousal based on social cues from the peer, which may be due to heightened social threat detection and/or empathic anxiety.
First mitogenome phylogeny of the sun bear Helarctos malayanus reveals a deep split between Indochinese and Sundaic lineages
Authors: Kunde Miriam N. , Barlow Axel , Klittich Achim M. , Yakupova Aliya , Patel Riddhi P. , Fickel Jörns , Förster Daniel W.
Published: April 2023

The sun bear Helarctos malayanus is one of the most endangered ursids, and to date classification of sun bear populations has been based almost exclusively on geographic distribution and morphology. The very few molecular studies focussing on this species were limited in geographic scope. Using archival and non‐invasively collected sample material, we have added a substantial number of complete or near‐complete mitochondrial genome sequences from sun bears of several range countries of the species' distribution. We here report 32 new mitogenome sequences representing sun bears from Cambodia, Thailand, Peninsular Malaysia, Sumatra, and Borneo. Reconstruction of phylogenetic relationships revealed two matrilines that diverged ~295 thousand years ago: one restricted to portions of mainland Indochina (China, Cambodia, Thailand; “Mainland clade”), and one comprising bears from Borneo, Sumatra, Peninsular Malaysia but also Thailand (“Sunda clade”). Generally recent coalescence times in the mitochondrial phylogeny suggest that recent or historical demographic processes have resulted in a loss of mtDNA variation. Additionally, analysis of our data in conjunction with shorter mtDNA sequences revealed that the Bornean sun bear, classified as a distinct subspecies (H. m. euryspilus), does not harbor a distinctive matriline. Further molecular studies of H. malayanus are needed, which should ideally include data from nuclear loci.
Using mechanistic insights to predict the climate‐induced expansion of a key aquatic predator
Authors: Urban Mark C. , Nadeau Christopher P. , Giery Sean T.
Published: April 2023

Ameliorating the impacts of climate change on communities requires understanding the mechanisms of change and applying them to predict future responses. One way to prioritize efforts is to identify biotic multipliers, which are species that are sensitive to climate change and disproportionately alter communities. We first evaluate the mechanisms underlying the occupancy dynamics of marbled salamanders, a key predator in temporary ponds in the eastern United States We use long‐term data to evaluate four mechanistic hypotheses proposed to explain occupancy patterns, including autumn flooding, overwintering predation, freezing, and winterkill from oxygen depletion. Results suggest that winterkill and fall flooding best explain marbled salamander occupancy patterns. A field introduction experiment supports the importance of winterkill via hypoxia rather than freezing in determining overwinter survival and rejects dispersal limitation as a mechanism preventing establishment. We build climate‐based correlative models that describe salamander occupancy across ponds and years at two latitudinally divergent sites, a southern and middle site, with and without field‐collected habitat characteristics. Correlative models with climate and habitat variation described occupancy patterns better than climate‐only models for each site, but poorly predicted occupancy patterns at the site not used for model development. We next built hybrid mechanistic metapopulation occupancy models that incorporated flooding and winterkill mechanisms. Although hybrid models did not describe observed site‐specific occupancy dynamics better than correlative models, they better predicted the other site's dynamics, revealing a performance trade‐off between model types. Under future climate scenarios, models predict an increased occupancy of marbled salamanders, especially at the middle site, and expansion at a northern site beyond the northern range boundary. Evidence for the climate sensitivity of marbled salamanders combined with their disproportionate ecological impacts suggests that they might act as biotic multipliers of climate change in temporary ponds. More generally, we predict that top aquatic vertebrate predators will expand into temperate‐boreal lakes as climate change reduces winterkill worldwide. Predaceous species with life histories sensitive to winter temperatures provide good candidates for identifying additional biotic multipliers. Building models that include biological mechanisms for key species such as biotic multipliers could better predict broad changes in communities and design effective conservation actions.
Recent advances in multimode microfluidic separation of particles and cells
Authors: Song Yongxin , Li Deyu , Xuan Xiangchun
Published: April 2023

Microfluidic separation of particles and cells is crucial to lab‐on‐a‐chip applications in the fields of science, engineering, and industry. The continuous‐flow separation methods can be classified as active or passive depending on whether the force involved in the process is externally imposed or internally induced. The majority of current separations have been realized using only one of the active or passive methods. Such a single‐mode process is usually limited to one‐parameter separation, which often becomes less effective or even ineffective when dealing with real samples because of their inherent heterogeneity. Integrating two or more separation methods of either type has been demonstrated to offer several advantages like improved specificity, resolution, and throughput. This article reviews the recent advances of such multimode particle and cell separations in microfluidic devices, including the serial‐mode prefocused separation, serial‐mode multistage separation, and parallel‐mode force‐tuned separation.
Expressing our passion in leadership
Authors: Skipworth Stan
Published: April 2023

As another school year ends, we may find ourselves taking note of and expressing our sentiments and feelings for others more deliberately. I find myself considering the unique form of passion that leaders have for their teams and team members. Passion is indeed a tremendously powerful element in any relationship, but the passion that is expressed through a leader's professional actions is something that has both a lasting and influential effect upon those whom the leader serves.
Solar photovoltaic water pump performance optimization by using response surface methodology
Authors: Waila Vipan Chand , Sharma Abhishek , Singh Vineet , Gupta Naveen Kumar
Published: April 2023

The constant depletion of the existing energy sources and their environmental effects have generated interest in employing renewable energy sources to power water pumping systems, such as solar‐photovoltaic. The research addresses the optimal photovoltaic (PV) power output, solar radiation, operating head, and tilt angle for maximum solar energy used to capture more solar radiation for solar water pumping for irrigation purposes. In order to get the best performance from the solar PV water pump, such as discharge (Q), hydraulic power (PH), pump efficiency (ήp), and overall efficiency (ήo), the design of experiments‐based response surface methodology was implemented in this work. The data required for the RSM model were obtained from the experimental work performed at location 28.67° N, 77.21° E, Delhi, India. The experiments performed at five different ranges of input variables PV power output (4000, 4250, 4500, 4750, and 5000 W), Solar radiation (200, 350, 500, 650, and 800 W/m2), operating head (15, 20, 25, 30, and 35 m) Tilt angle (5°, 10°, 15°, 20°, and 25°). The best output parameters The best conditions for a solar PV water pump (16.8 m3/h discharge, 1.85 kW hydraulic power, 81.15% pump efficiency, and 16.12% overall efficiency) were discovered to be Po 5000 W, SA 260 W/m2, Head 35 m, and TA 19°. The predicted result was validated using an RSM‐based solution, and the error% was found to be within acceptable limits (>5%). The desirability 0.963 of the model was indicating the good solution.
Enhancing the network specific individual characteristics in rs‐fMRI functional connectivity by dictionary learning
Authors: Jain Pratik , Chakraborty Ankit , Hafiz Rakibul , Sao Anil K. , Biswal Bharat
Published: April 2023

Most fMRI inferences are based on analyzing the scans of a cohort. Thus, the individual variability of a subject is often overlooked in these studies. Recently, there has been a growing interest in individual differences in brain connectivity also known as individual connectome. Various studies have demonstrated the individual specific component of functional connectivity (FC), which has enormous potential to identify participants across consecutive testing sessions. Many machine learning and dictionary learning‐based approaches have been used to extract these subject‐specific components either from the blood oxygen level dependent (BOLD) signal or from the FC. In addition, several studies have reported that some resting‐state networks have more individual‐specific information than others. This study compares four different dictionary‐learning algorithms that compute the individual variability from the network‐specific FC computed from resting‐state functional Magnetic Resonance Imaging (rs‐fMRI) data having 10 scans per subject. The study also compares the effect of two FC normalization techniques, namely, Fisher Z normalization and degree normalization on the extracted subject‐specific components. To quantitatively evaluate the extracted subject‐specific component, a metric named is proposed, and it is used in combination with the existing differential identifiability metric. It is based on the hypothesis that the subject‐specific FC vectors should be similar within the same subject and different across different subjects. Results indicate that Fisher Z transformed subject‐specific fronto‐parietal and default mode network extracted using Common Orthogonal Basis Extraction (COBE) dictionary learning have the best features to identify a participant.
Using hydrogen and oxygen stable isotopes to estimate soil water evaporation loss under continuous evaporation conditions
Authors: Li Yang , Huo Siyuan , Guo Jing , Sun Jie , Pan Jie , Wang Deng , Tan Qiankun , Pei Bingbing
Published: April 2023

The use of hydrogen and oxygen stable isotopes in estimating soil water evaporation loss under continuous evaporation conditions is crucial for gaining insight into soil water movement processes under different conditions. In this study, via high‐frequency meteorological monitoring and continuous soil water measurements, we investigated the variation of hydrogen and oxygen stable isotopes and soil water fluxes with soil depth and time for soil water at different depths under continuous evaporation conditions. The precipitation isotope δrain and soil water flux changes were determined using the Craig‐Gordon model. It was shown that the isotopic fractionation of soil water in the surface layer 0–30 cm was dominated by a gaseous‐dominated transport process, and that both the δ18O and δD values and evaporative intensity decreased with increasing soil depth. In terms of time dynamics, the evaporation loss of soil water varies continuously with seasons and is the highest during summer. The use of δ18O to quantify the soil water evaporation loss provides greater accuracy than that provided by δD. The relative errors in the evaporation loss calculated based on δ18O and δD were 13% and 34%, respectively. A sensitivity analysis of each parameter indicated that the relative error calculated by the model is primarily determined by temperature and relative humidity uncertainty. The sensitivity analysis reveals the critical evaporation intensity of soil water at various depths from unsteady to steady state evaporation. When the relative humidity changes by 1%, the evaporation loss fraction changes from 0.001 to 0.034. The results of this study are important for quantifying the soil water resources in arid and semi‐arid areas without precipitation using stable isotopes of hydrogen and oxygen.
Phosphorus Corroles: Tuning of their Photophysical and Redox Properties via Axial Ligation and Macrocycle Modification
Authors: Sinha Woormileela , Fridman Natalia , Mahammed Atif , Gross Zeev
Published: April 2023

Given the increased interest in phosphorus corroles for many applications, we now report how their photophysical variables and redox potentials may be tuned. This was performed by focusing on a series of derivatives that significantly differ in terms of the chelating corrole macrocycle: three C6F5vs. three CF3substituents on themeso‐C atoms, Hvs. Br atoms on the β‐pyrrole positions, and monomericvs. dimeric (throughβ‐pyrrole C−C bonds). Also studied was the effect of the phosphorus axial ligands, hydroxidevs. fluoride.
miRNA‐128 and miRNA‐223 regulate cholesterol‐mediated drug resistance in breast cancer
Authors: Palma Gabriella Bianca Henriques , Kaur Mandeep
Published: April 2023

Background

Breast cancer is the second most common malignancy worldwide and 70% of all breast cancer cases are estrogen receptor‐positive (ER+). Endocrine therapy, Tamoxifen (TAM), is a popular treatment for ER+ breast cancer patients; however, despite its success in reducing breast cancer mortality, cancer drug resistance remains a significant challenge. A major contributor to this resistance is the dysregulation of cholesterol homeostasis, where breast cancer cells have elevated cholesterol levels. MicroRNAs (miRNAs) are master regulators of cholesterol‐related and cancer drug resistance pathways, and their aberrant expression often confers resistance. Therefore, we aimed to investigate the roles of miRNA‐128 and miRNA‐223 in cholesterol‐mediated TAM resistance.

Methods

Three breast cancer cell lines were treated with a combination of 1 μM TAM and 10 μM of a cholesterol depleting agent (Acetyl Plumbagin: AP) following transfection with a miR‐128 inhibitor or a miR‐223 mimic. Cell viability and cholesterol levels were assessed using an MTT assay and fluorescence staining, respectively. In addition, expression levels of several genes and proteins involved in cancer drug resistance and cholesterol homeostasis were also assessed using RT‐qPCR and western blotting.

Results

The combination treatment with altered miRNA expression led to reduced cell viability due to a reduction in free cholesterol and lipid rafts in MCF‐7, MDA‐MB‐231, and long‐term estrogen‐deprived cells (resistant breast cancer cells). Moreover, reduced miR‐128 expression was favoured in all breast cancer cell lines as this alteration lowered the expression of genes involved in cholesterol synthesis and transport, drug resistance, and cell signalling.

Conclusions

Investigating the gene expression profiles in different breast cancer cell lines was important to elucidate further the molecular mechanisms involved in miRNA‐regulated cholesterol homeostasis and cancer drug resistance. Therefore, our findings demonstrated that miR‐128 and miR‐223 could be potential targets in reducing TAM resistance through the depletion of excess cholesterol.
Enhancement of luminous efficacy of polymer light‐emitting diodes with silver‐nanoparticles by oxygen‐plasma treatment
Authors: Chen Sy‐Hann , Hong Yi‐Wen , Chau Yuan‐Fong Chou , Huang Hung Ji , Chiang Hai‐Pang
Published: April 2023

Silver‐nanoparticles deposited on indium tin oxide (AgNPs/ITO) with different O2‐plasma treatment times are used as the anode window substrate for polymer light‐emitting diodes (PLED). When AgNPs/ITO with an O2‐plasma treatment time of 10 min is used for PLED, a maximum current efficiency of 3.33 cd/A is realized, which is notably higher than that of a reference PLED (1.00 cd/A). Compared to those of the reference PLED, the mean current efficiency and electroluminescence intensity of the optimal PLED are enhanced by 3.24 times and 480%, respectively. O2‐plasma treatment is an easy method for optimizing the localized surface plasmon resonance effect of metal nanoparticles, exhibiting advantages of scalable mass production and high suitability for applications in related optoelectronic components.
Evidence of dissolved trivalent manganese in acidic forest soils
Authors: Lux Constantin , Mansfeldt Tim
Published: April 2023

Background

Evidence of trivalent manganese (Mn3+) in the aqueous phase of soils is unknown so far although this strong oxidant has large environmental implications.

Aims

We aimed to modify a spectrophotometric protocol (porphyrin method) and to discriminate between Mn2+ and Mn3+ in the aqueous phase of forest soils based on kinetic modeling.

Methods

We investigated manganese speciation in 12 forest floor solutions and 41 soil solutions from an acidic forest site by adjusting pH and correcting for absorbance.

Results

The solutions showed broad ranges in pH (3.4−6.3), dissolved organic carbon (DOC, 1.78−77.1 mg C L−1), and total Mn (MnT, 23.9−908 µg L−1). For acidic solutions, a pH‐buffer was added to increase the pH of the solutions to 7.5−8.0, and background absorption was corrected for colored solutions, that is, solutions high in DOC. This was done to accelerate the reaction kinetics and avoid overestimation of MnT concentrations. After the pH and color adjustments, the comparison of MnT concentrations between the porphyrin method and optical emission spectrometry showed good agreement. Trivalent Mn, which is stabilized by organic ligands, constitutes significant proportions in both forest floor solutions (10−87%) and soil solutions (0.5−74%).

Conclusions

The dissolved Mn3+ is present in acidic forest soils. Thus, we revise the paradigm that this species is not stable and encourage to apply the revised method to other soils.
High‐efficiency folded optics for near‐eye displays
Authors: Luo Zhenyi , Ding Yuqiang , Rao Yi , Wu Shin‐Tson
Published: April 2023

Pancake lens structure offers a promising solution to compact formfactor for near‐eye displays. However, utilizing a half mirror to triple the optical path length causes a dramatic optical loss. The theoretical maximum optical efficiency is only 25%. To balance the tradeoff between compact formfactor and optical efficiency, here we propose a new folded optical structure with a doubled efficiency and doubled optical path length, using two polarization‐selective cholesteric liquid crystal reflectors. Simulation results agree with the experiment reasonably well. Two display configurations are established to evaluate the imaging performances of the proposed pancake lens structure.
Systemic vascular photobiomodulation accelerates the recovery of motor activity in rats following spinal cord injury
Authors: Tobelem Daysi da C. , Andreo Lucas , Silva Tamiris , Malavazzi Tainá C. S. , Martinelli Andreia , Horliana Anna Carolina R. T. , Fernandes Kristianne P. S. , Bussadori Sandra K. , Mesquita‐Ferrari Raquel A.
Published: April 2023

Objectives

Spinal cord injury (SCI) causes the discontinuity of the spinal canal, leading to functional and sensorial losses in areas below the injury, which are often irreversible. Photobiomodulation (PBM) can enhance the neuromuscular repair process, especially in cases of peripheral nerve injuries. However, there is little knowledge regarding the effects of this therapeutic modality on recovery following a SCI, especially the noninvasive systemic form denominated vascular PBM (VPBM). To analyze the effects of VPBM in the immediate, acute and intermediate phases following a compression‐induced SCI on morphological aspects of neuromuscular tissue repair, functional recovery and the protein expression of brain‐derived neurotrophic factor (BDNF).

Methods

Wistar rats were divided into five groups: control, SCI, SCI + VPBM‐Im (immediate administration of VPBM), SCI + VPBM‐2h (VPBM administered 2 h after injury) and SCI + VPBM‐14d (VPBM administered 14 days after injury). VPBM was administered in the region of the caudal vein/artery with low‐level laser (AsGaAl, 780 nm, 80 J/cm², 40 mW for 80 s, totaling an energy of 3.2 J over a single point) for 14 consecutive days. During the analysis periods (1, 3, 7, 14, 21, 28 and 35 days after injury), functioning was evaluated using the Basso‐Beattie‐Bresnahan (BBB) index. At the end of each experimental period, blood samples were collected for the determination of the concentration of circulating BDNF using ELISA. Muscle tissue and nerve tissue samples were also extracted for morphological and histological analyses using H&E staining.

Results

SCI + VPBM‐Im and SCI + VPBM‐2 h led to the recovery of motor function beginning on the 7th day after injury (p < 0.05), an increase in the cross‐sectional area (CSA) of the muscle fibers in the second week (p < 0.05) and an increase in muscle fiber diameter beginning on Day 14 (p < 0.05). Early irradiation had a greater effect on the reduction in the size of the cavity, with stabilization of the cavity found on Day 7 (p < 0.05). Considering the circulating BDNF levels, no changes was found during the experimental periods.

Conclusion

The present results showed that VPBM was capable of modulating morphological and functional recovery following SCI, especially when administered early. The positive effects on functional recovery were demonstrated by the BBB index; the reestablishment of the structure of the muscle and nerve tissue was demonstrated by the preservation of CSA and diameter of muscle fiber and reduction in the area of the injury (cavity size) respectively. Thus, noninvasive VPBM may be an important component of treatment for spinal cord injuries.
The Process‐Directed Self‐Assembly of Block Copolymer Particles
Authors: Zhu Yanyan , Huang Changhang , Zhang Liangshun , Andelman David , Man Xingkun
Published: April 2023

The kinetic paths of structural evolution and formation of block copolymer (BCP) particles are explored using dynamic self‐consistent field theory (DSCFT). It is shown that the process‐directed self‐assembly of BCP immersed in a poor solvent leads to the formation of striped ellipsoids, onion‐like particles and double‐spiral lamellar particles. The theory predicts a reversible path of shape transition between onion‐like particles and striped ellipsoidal ones by regulating the temperature (related to the Flory–Huggins parameter between the two components of BCP, χAB) and the selectivity of solvent toward one of the two BCP components. Furthermore, a kinetic path of shape transition from onion‐like particles to double‐spiral lamellar particles, and then back to onion‐like particles is demonstrated. By investigating the inner‐structural evolution of a BCP particle, it is identified that changing the intermediate bi‐continuous structure into a layered one is crucial for the formation of striped ellipsoidal particles. Another interesting finding is that the formation of onion‐like particles is characterized by a two‐stage microphase separation. The first is induced by the solvent preference, and the second is controlled by the thermodynamics. The findings lead to an effective way of tailoring nanostructure of BCP particles for various industrial applications.
Existence of weak solutions for a nonhomogeneous incompressible cell–fluid Navier–Stokes model with chemotaxis
Authors: Lopes Juliana Honda , Planas Gabriela
Published: April 2023

This work is concerned with the mathematical analysis of a general cell–fluid Navier–Stokes model with the inclusion of chemotaxis. This general model relays on a mixture theory multiphase formulation. It consists of two mass balance equations and two general momentum balance equations, respectively, for the cell and fluid phase, combined with a convection–diffusion–reaction equation for oxygen. We investigate the existence of weak solutions in a two‐ or three‐dimensional bounded domain when the fluids are assumed to be incompressible with constant volume fraction.
Correction of errors in estimates of T1ρ at low spin‐lock amplitudes in the presence of B0 and B1 inhomogeneities
Authors: Zu Zhongliang , Adelnia Fatemeh , Harkins Kevin , Wang Feng , Ostenson Jason , Gore John C.
Published: April 2023

Relaxation rates R1ρ in the rotating frame measured by spin‐lock methods at very low locking amplitudes (≤ 100 Hz) are sensitive to the effects of water diffusion in intrinsic gradients and may provide information on tissue microvasculature, but accurate estimates are challenging in the presence of B0 and B1 inhomogeneities. Although composite pulse preparations have been developed to compensate for nonuniform fields, the transverse magnetization comprises different components and the spin‐lock signals measured do not decay exponentially as a function of locking interval at low locking amplitudes. For example, during a typical preparation sequence, some of the magnetization in the transverse plane is nutated to the Z‐axis and later tipped back, and so does not experience R1ρ relaxation. As a result, if the spin‐lock signals are fit to a monoexponential decay with locking interval, there are residual errors in quantitative estimates of relaxation rates R1ρ and their dispersion with weak locking fields. We developed an approximate theoretical analysis to model the behaviors of the different components of the magnetization, which provides a means to correct these errors. The performance of this correction approach was evaluated both through numerical simulations and on human brain images at 3 T, and compared with a previous correction method using matrix multiplication. Our correction approach has better performance than the previous method at low locking amplitudes. Through careful shimming, the correction approach can be applied in studies using low spin‐lock amplitudes to assess the contribution of diffusion to R1ρ dispersion and to derive estimates of microvascular sizes and spacings. The results of imaging eight healthy subjects suggest that R1ρ dispersion in human brain at low locking fields arises from diffusion among inhomogeneities that generate intrinsic gradients on a scale of capillaries (~7.4 ± 0.5 μm).
Attitude and influencing factors to receive the COVID‐19 vaccine among university students in Sichuan Province, China: A cross‐sectional study
Authors: Yang Kaihan , Chi Yang , Wan Jiamin , Qing Xuedan , Peng Yubinxin , Chen Hong , Li Jiehang , Jiang Xiaolian
Published: April 2023

Aims

To explore the university students' attitude and the potential influencing factors to receive the coronavirus disease 2019 (COVID‐19) vaccine in Sichuan Province, China.

Design

A cross‐sectional study.

Methods

The self‐designed questionnaire was distributed among university students online in June 2021. SPSS software was used for statistical analysis of the data. Descriptive statistics, Chi‐square, two independent samples t‐tests, one‐way analysis of variance (ANOVA), multivariate linear regression, and content analysis were performed.

Results

A total of 397 questionnaires were analysed, involving 316 (79.6%) respondents have received at least one dose of a COVID‐19 vaccine and 81 (20.4%) have not taken the vaccine. The total mean score of university students' vaccination attitude was 25.97 (standard deviation [SD] = 3.720), and the total scoring rate was 74.2%. Main factors influencing students' attitude included education level, major, living style, with chronic disease or not, self‐reported vaccination status, and number of medical units that can provide vaccination within 3 km of residence. Students were more willing to choose Chinese‐manufactured vaccines (66.8%) and participate in collective vaccination programs organized by the school (71.3%). The desired vaccine protection period was 5–10 years (42.1%). The top three reasons for refusing the vaccine or vaccine hesitancy were as follows: concern about the side effects of vaccine (44.8%), lack of information about vaccine (31.0%), and concern about the efficacy of vaccine (29.3%).

Conclusion

In general, most of the participants had relatively high level of positive attitude to receive the COVID‐19 vaccine. Nevertheless, more attention should be paid to postgraduate students, non‐medical students, those living alone, those with chronic disease, those have not received the COVID‐19 vaccine, and those living far away from the vaccination medical units. Findings of this study can help educational institutions in developing effective interventions to improve the vaccination rate in the university student population.
Robust formation control of uncertain linear multi‐agent systems in presence of time‐delay using output information
Authors: Pal Arnab , Naskar Asim Kr.
Published: April 2023

A major challenge in multi‐agent formation is the issue of delay and uncertainty. This article investigates a robust formation control problem for linear multi‐agent systems with input delay and model uncertainty. The strategy adopted by an agent in the system aims to predict the delayed state using output information from neighboring agents over a fixed communication network and generate the control input from the predictor output. The predictor is employed using the finite spectrum assignment (FSA) technique. The overall strategy leads to a unified framework representation, and the multi‐agent formation control problem is simplified to a closed‐loop stability problem for an agent. The overall problem comes down to deciding two feedback gains: predictor gain and controller gain. For a perfect plant model, any choice of stabilizing gains can achieve formation. But when agent models are uncertain, the gains need to be derived from the solutions of linear matrix inequalities (LMIs) containing network information and delay. LMIs are obtained from the bounded real lemma and the gains obtained from the solution guarantee to maximize the norm bound of allowable perturbation, modeled as additive uncertainty, for a known delay size. Further, since the FSA technique is sensitive to discretization, a digital implementation of the overall scheme is elaborated, which may help to debug stability issues in the implementation process. Finally, numerical examples are presented to demonstrate the effectiveness of the proposed ideas.
Normative Values for the Inner EAR Scale
Authors: Zhou Allen S. , Corrales Carleton Eduardo , Prince Anthony , Yueh Bevan , Shin Jennifer J.
Published: April 2023

Objective

To determine normative values for the Inner Effectiveness of Auditory Rehabilitation (Inner EAR) scale, a validated instrument utilized to study the impact of hearing loss and potential treatments.

Study Design

Observational outcomes study.

Setting

Academic medical center and community care sites.

Methods

We included patients who were at least 18 years of age and completed the Inner EAR scale, pure‐tone audiometry, and word recognition score assessment. Based on audiometry results, patients were categorized as having: (1) normal bilateral hearing, (2) unilateral hearing loss, and (3) bilateral hearing loss. The distributions of Inner EAR scale scores were assessed within each category. Fisher's exact test was utilized to determine whether data‐driven threshold values could discriminate among the 3 clinical groups.

Results

Two hundred and twenty‐two consecutive patients with hearing‐related complaints met inclusion criteria. Mean Inner EAR scores for patients with bilateral hearing loss (29.2, interquartile range [IQR] 10‐41.5), unilateral hearing loss (38.9, IQR 23‐49), and normal hearing (46.6, IQR 31‐62) were significantly different (analysis of varianceF < 0.0001). An Inner EAR score threshold of 50 supported the ability to statistically significantly discriminate between bilateral hearing loss and normal hearing (p = .003), as well as between unilateral hearing loss and normal hearing (p = .015).

Conclusion

An Inner EAR score normative threshold value of 50 provides significant discriminatory ability between normal hearing and unilateral or bilateral hearing loss on audiometry. Normative values provide useful, frequently referenced data when assessing responses to treatment. Based on these data, this threshold may help distinguish patients with and without perceived functional impact from hearing loss.
Effective antimicrobial therapies of urinary tract infections among children in low‐ and middle‐income countries: A systematic review
Authors: Ara Rifat , Nasrullah Sarker Mohammad , Tasnim Zarrin , Afrin Sadia , Hawlader Mohammad Delwer Hossain , Saif‐Ur‐Rahman KM
Published: April 2023

Importance

Urinary tract infection (UTI) is one of the most common infections encountered in infancy and childhood. Despite the emerging problem of antibiotic resistance in recent years, the use of antibiotics for better management of UTIs is inevitable.

Objective

This study aims to explore the efficacy and adverse effects of the available antimicrobial agents that are used in pediatric UTIs in low‐ and middle‐income countries (LMICs).

Methods

Five electronic databases were searched to identify relevant articles. Two reviewers independently performed screening, data extraction, and quality assessment of the available literature. Randomized controlled trials providing antimicrobial interventions in both male and female participants within the age range of 3 months to 17 years in LMICs were included.

Results

Six randomized controlled trials from 13 LMICs were included in this review (four trials explored the efficacy). Due to high heterogeneity across the studies, a meta‐analysis was not performed. Other than attrition and reporting bias, the risk of bias was moderate to high due to poor study designs. The differences in the efficacy and adverse events of different antimicrobials were not found to be statistically significant.

Interpretation

This review indicates the necessity for additional clinical trials on children from LMICs with more significant sample numbers, adequate intervention periods, and study design.
Research progress of self‐healing polymer materials for flexible electronic devices
Authors: Zhu Shanshan , Liu Zhihao , Li Wenyao , Zhang Haiwei , Dai Guoliang , Zhou Xing
Published: April 2023

Self‐healing polymer materials have been a research hotspot in the field of smart materials since their invention. They have self‐diagnostic functions and are capable of self‐healing small cracks. By applying self‐healing materials to flexible electronic devices, the mechanical damage caused by bending, folding and scratching of these devices can be reduced. The reliability and service life of the devices could be improved accordingly. This paper provides a brief overview of self‐healing polymers and focuses on their applications in flexible electronic devices. In addition, this paper prospects the future development and challenges of self‐healing polymer materials.
Absence of botanical European Palaeolithic cave art: What can it tell us about plant awareness disparity?
Authors: Walton Georgina , Mitchley Jonathan , Reid Geraldine , Batke Sven
Published: April 2023

Societal Impact Statement

Cave art has been an integral part of human history, providing a glimpse into the lives and cultures of our ancestors. Prehistoric botanical art is an important medium that can help us to redefine our intimate relationship with plants. The findings from our work provide some evidence from the European Palaeolithic period that modern plant awareness disparity (PAD) might be more deeply rooted in our past. By inspiring a deeper appreciation and understanding of the natural world, cave art can help people to reconnect with plants, thus tackling PAD.