bluuebunny/crossref_metadata_2025 huggingface dataset:
New [1,2,4]triazolo[4,3‐c]quinazoline derivatives as vascular endothelial growth factor receptor‐2 inhibitors and apoptosis inducers: Design, synthesis, docking, and antiproliferative evaluation
Authors: Azab Ahmed E. , Alesawy Mohamed S. , Eldehna Wagdy M. , Elwan Alaa , Eissa Ibrahim H.
Published: July 2022

In continuation of our previous efforts in the field of design and synthesis of vascular endothelial growth factor receptor (VEGFR)‐2 inhibitors, a new series of [1,2,4]triazolo[4,3‐c]quinazoline derivatives were designed and synthesized as modified analogs of some reported VEGFR‐2 inhibitors. The synthesized compounds were designed to have the essential pharmacophoric features of VEGFR‐2 inhibitors. Antiproliferative activities of the synthesized compounds were investigated against two tumor cell lines (HepG2 and HCT‐116) using sorafenib as a positive control. Compound 10k emerged as the most promising antiproliferative agent with IC50 values of 4.88 and 5.21 µM against HepG2 and HCT‐116 cells, respectively. Also, it showed the highest inhibitory activity against VEGFR‐2 with an IC50 value of 53.81 nM compared to sorafenib (IC50 = 44.34 nM). Cell cycle analysis revealed that compound 10k can arrest HepG2 cells at both the S and G2/M phases. In addition, this compound produced a tenfold increase in apoptotic cells compared to the control. Furthermore, the effect of compound 10k on the expression level of BAX, Bcl‐2, and caspase‐3 was assessed. This compound caused a 3.35‐fold increase in BAX expression levels and a 1.25‐fold reduction in Bcl‐2 expression levels. The BAX/Bcl‐2 ratio was calculated to be 4.57, indicating a promising apoptotic effect. It also showed a significant increase in the level of caspase‐3 (4.12‐fold) compared to the control cells. In silico docking, absorption, distribution, metabolism, excretion, and toxicity, and toxicity studies were performed for the synthesized compounds to investigate their binding patterns against the proposed biological target (VEGFR‐2) and to assess the drug‐likeness characters.
Design of output feedback proportional–integral controller for polynomial fuzzy systems
Authors: Radmanesh Hamid Reza , Moarefianpour Ali , Jahed‐Motlagh Mohammad Reza
Published: July 2022

In this paper, the design of dynamic output feedback control law for polynomial fuzzy systems is studied. The main purpose is to design a tracker control law for fuzzy polynomial systems that are subject to external bounded disturbances. The structure of the control law is considered as fuzzy proportional–integral control. The conditions for deriving the control law are formulated in the form of a sum of square (SOS) feasibility problem. The designed control law will be able to force the system state vector to follow the state vector of a stable reference model in addition to guaranteeing the
performance measure. The simulation results show the efficiency of the proposed method exposed to external disturbance.
Determination of the biochemical methane potential of food waste after aerobic storage and aeration pretreatment
Authors: Oliveira Bruna Patrícia de , Sganzerla William Gustavo , Léo Patricia , Forster‐Carneiro Tânia , Martins Gilberto
Published: July 2022

Food waste represents a relevant fraction of municipal solid organic waste, and anaerobic digestion can be an eco‐friendly alternative for sustainable management in a circular economy framework. One of the challenges to the implementation of anaerobic digestion is the availability of easily degradable compounds in the substrate, which can be solved by the application of pretreatment to increase methane production. In this study, the influence of aerobic storage time and forced continuous aeration pretreatment on the biochemical methane potential of food waste was evaluated. The results demonstrate an increase in the methane production concerning the total volatile solids (TVS) of food waste stored for 7 days (425 NmL CH4 g−1 TVS) compared with fresh samples without pretreatment (375 NmL CH4 g−1 TVS). The adoption of forced and continuous aeration pretreatment on food waste for 4 days produced 456 NmL CH4 g−1 TVS for the leachate, 1.22‐fold higher than that for the food waste without storage. In conclusion, the application of aeration pretreatment previous to anaerobic digestion can be an alternative to increase the methane potential from food waste. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.
Flexible customization of the self‐assembling abilities of short elastin‐like peptide Fn analogs by substituting N‐terminal amino acids
Authors: Suyama Keitaro , Shimizu Marin , Maeda Iori , Nose Takeru
Published: July 2022

Elastin‐like peptides (ELPs) are thermoresponsive biopolymers inspired by the characteristic repetitive sequences of natural elastin. As ELPs exhibit temperature‐dependent reversible self‐assembly, they are expected to be biocompatible thermoresponsive materials for drug delivery carriers. One of the most widely studied ELPs in this field is the repetitive pentapeptide, (VPGXG)n. We previously reported that phenylalanine‐containing ELP (Fn) analogs, in which the former Val residue of the repetitive sequence (VPGVG)n is replaced by Phe, show coacervation with a short chain length (n = 5). Owing to their short sequences, Fn analogs are easily modified in amino acid sequences via simple chemical synthesis, and are useful for investigating the relationship between peptide sequences and temperature responsiveness. In this study, we developed Fn analogs by replacing Phe residue(s) with other amino acids or introducing another amino acid at the N‐terminus. The temperature responsiveness of the Fn analogs changed drastically with the substitution of a single Phe residue, suggesting that aromatic amino acids play an important role in their self‐assembly. In addition, the self‐assembling ability of Fn was enhanced by increasing the bulkiness of the N‐terminal amino acids. Therefore, the N‐terminal residue was considered to be important for hydrophobicity‐induced intermolecular interactions between the peptides during coacervation.
Improving yield of a recombinant biologic in a Brassica hairy root manufacturing process
Authors: Gutierrez‐Valdes Noemi , Häkkinen Suvi T. , Lemasson Camille , de Groot Jonas , Ele‐Ekouna Jean‐Pierre , Guillet Marina , Cardon Florian , Ritala Anneli
Published: July 2022

Hairy root systems have proven to be a viable alternative for recombinant protein production. For recalcitrant proteins, maximizing the productivity of hairy root cultures is essential. The aim of this study was to optimize a Brassica rapa rapa hairy root process for secretion of alpha‐
l‐iduronidase (IDUA), a biologic of medical value. The process was first optimized with hairy roots expressing eGFP. For the biomass optimization, the highest biomass yields were achieved in modified Gamborg B5 culture medium. For the secretion induction, the optimized secretion media was obtained with additives (1.5 g/l PVP + 1 mg/l 2,4‐
d + 20.5 g/l KNO3) resulting in 3.4 fold eGFP secretion when compared to the non‐induced control. These optimized conditions were applied to the IDUA‐expressing hairy root clone, confirming that the highest yields of secreted IDUA occurred when using the defined additive combination. The functionality of the IDUA protein, secreted and intracellular, was confirmed with an enzymatic activity assay. A > 150‐fold increase of the IDUA activity was observed using an optimized secretion medium, compared with a non‐induced medium. We have proven that our B. rapa rapa hairy root system can be harnessed to secrete recalcitrant proteins, illustrating the high potential of hairy roots in plant molecular farming.
A course‐based undergraduate research experience to illustrate the early stages of the drug discovery process
Authors: García‐Caballero Melissa , Moya‐García Aurelio , Torres‐Vargas José Antonio , García‐Ponce Ángel Luis , Rodríguez‐Quesada Ana
Published: July 2022

We have implemented at the University of Málaga (Spain) a new course‐based undergraduate research experience (CURE) to involve undergraduate students of Science in a real‐world scientific problem. Within the topic “Let's find acetylcholinesterase inhibitors as new drug candidates for the treatment of Alzheimer's”, students have been engaged into the early stages of the drug discovery process. Working in groups of 4–5 persons, they have searched information in databases, proposed solutions to the driving question and designed protocols to carry them out in vitro and in silico. Overall, the implementation of this experience has been very satisfactory in terms of academic performance and students' perception. This article reports a session from the virtual international 2021 IUBMB/ASBMB workshop, “Teaching Science on Big Data”.
Prediction of pathological complete response to neoadjuvant chemotherapy in patients with breast cancer using a combination of contrast‐enhanced ultrasound and dynamic contrast‐enhanced magnetic resonance imaging
Authors: Han Xue , Yang Huajing , Jin Shiyang , Sun Yunfeng , Zhang Hongxia , Shan Ming , Cheng Wen
Published: July 2022

This study aimed to evaluate the value of dynamic contrast‐enhanced ultrasound (CEUS) combined with dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) in predicting pathological complete response (pCR) in patients with breast cancer receiving neoadjuvant chemotherapy (NAC). Fifty‐seven female patients with breast cancer (mean age, 50.46 years; range, 32–66 years) scheduled for NAC were recruited. CEUS and DCE‐MRI were performed before and after NAC. Imaging features and their changes were compared with postoperative pathological results. After the clinical differences were balanced using propensity score matching, univariate and multiple logistic regression analyses were used to derive the characteristics independently associated with pCR. Receiver operating characteristic curve analysis was performed to assess diagnostic performance. After six to eight cycles of NAC, 24 (42.1%) patients achieved pCR, while 33 (57.9%) did not. Multivariate analysis showed that enhancement order on CEUS and DCE‐MRI before NAC, reduction in diameter and enhancement shape on CEUS, maximum diameter on DCE‐MRI, and the type of progressive dynamic contrast enhancement after NAC were independently associated with pCR after NAC. The area under the receiver operating characteristic curve for CEUS+DCE‐MRI was 0.911 (95% confidence interval, 0.826–0.997), and the specificity and positive predictive values were 87.0% and 87.5%. CEUS and DCE‐MRI have the potential for assessing the pathological response to NAC in patients with breast cancer; their combination showed the best diagnostic performance. CEUS+DCE‐MRI has proved beneficial for comprehensive assessment and personalizing treatment strategies for patients with breast cancer.
Adolescent and young adult (AYA) oncology: A credentialed area of focused competence in Canada
Authors: Srikanthan Amirrtha , Karpinski Jolanta , Gupta Abha
Published: July 2022

Background

Adolescents and young adults (AYA, ages 15–39 years) affected by cancer have unique treatment, survivorship, and palliation concerns. Current oncology training does not focus on the distinctive needs of this demographic. Amid this recognition, the Canadian National AYA Cancer Task Force and Canadian Partnership Against Cancer have advocated the need for clinicians with formalized AYA experience. To address this need and standardize training, a national task force developed criteria for structured academic programs in AYA Oncology in Canada.

Methods

Workshops were organized to identify and establish the fundamentals of practice in AYA Oncology through consensus. These workshops followed the pre‐existing rigorous process established by the Royal College of Physicians and Surgeons of Canada (Royal College) for new program development. The process includes: (i) developing the tasks associated with the discipline's practice, (ii) identifying the evidence trainees must provide to demonstrate tasks can be performed independently (the competence portfolio), (iii) developing training requirements and summarizing the knowledge, skills and attitudes required to perform these tasks, and (iv) identifying specific experiences essential to acquiring skills and demonstrating competent performance.

Results

AYA Oncology is a recognized an Area of Focused Competence (AFC) by the Royal College.

Conclusion

The AFC designation in AYA Oncology provides a standardized curriculum, training experience and accreditation process to attract oncologists, promote expertise and advance AYA oncology care.
A hierarchy of sustainable grocery shopping behaviours: Using Rasch modelling to explore adoption groups
Authors: Ganglmair‐Wooliscroft Alexandra , Wooliscroft Ben
Published: July 2022

Grocery shopping is a major contributor to unsustainable consumption in the developed world. This study constructs a hierarchy of sustainable grocery shopping (SGS), using a broad range of SGS consumption activities that contribute to an individual's aggregate grocery shopping. We confirm the suitability of Rasch modelling to construct the SGS hierarchy and, recognize the definitional equivalence between features of the Rasch model and Rogers' adoption groups. Our results are transformed into theoretically founded, empirically observed SGS adoption segments. SGS adoption groups are analysed with reference to multiple research streams. Our results show that the diffusion of SGS behaviours in a population is in its early stages and most SGS adoption segments undertake a limited number of SGS behaviours. Demographic characteristics do not contribute to explaining SGS membership, but personal values do. Personal values are also related to the observation of spill‐over between items of similar behavioural difficulty, rather than within product categories. Only the most advanced SGS adoption groups consider sustainably sourced food as a decision criteria. We show the importance of investigating SGS with a systemic approach.
Design, Synthesis and Biological Evaluation of Novel Spiro‐[Chroman‐2,4′‐Piperidin]‐4‐One Analogs as Anti‐Tubercular Agents
Authors: Chitti Surendar , Nandikolla Adinarayana , Khetmalis Yogesh Mahadu , Van Calster Kevin , Kumar Boddupalli Venkata Siva , Kumar Banoth Karan , Murugesan Sankaranarayanan , Cappoen Davie , Sekhar Kondapalli Venkata Gowri Chandra
Published: July 2022

A series of novel spiro‐[chromane‐2,4′‐piperidin]‐4(3H)‐one derivatives were designed, synthesized and structures were confirmed by analytical methods, viz., 1H‐NMR, 13C‐NMR and mass spectrometry. The synthetic derivatives were evaluated for their anti‐tuberculosis (anti‐TB) activity against Mycobacterium tuberculosis (Mtb) strain H37Ra. Among all the evaluated Compounds, PS08 exhibited significant inhibition with MIC value of 3.72 μM while MIC values of the remaining Compounds ranged from 7.68 to 230.42 μM in comparison to the standard drug INH (MIC 0.09 μM). The two most active Compounds however showed acute cytotoxicity towards the human MRC‐5 lung fibroblast cell lines. The in silico ADMET profiles of the titled Compounds were predicted and found within the prescribed limits of the Lipinski and Jorgenson rules. Molecular docking study of the notably active Compound (PS08) was also carried out after performing validation in order to understand the putative binding position of the test ligand at the active site of selected target protein Mtb tyrosine phosphatase (PtpB).
Rapid Aging of Binder‐Free Zeolite NaY Beads in Thermal Energy Storage Applications
Authors: Auer Bernhard , Rönsch Stefan
Published: July 2022

Zeolites can be used to store thermal energy, but they may age and lose a fraction of their storage capacity during prolonged use. The purpose of this study is to determine which parameters are responsible for the aging of the zeolite NaY by exposing it to extreme hydrothermal conditions. In a laboratory unit, a fixed bed of binder‐free zeolite NaY beads was treated hydrothermally, and the beads were analyzed for signs of aging. Also, a fixed bed of binder‐free zeolite 13X beads was tested for comparison. The results indicate that the two zeolite types age differently, depending on temperature and time of exposure.
Hilbert‐Huang Transform Analysis of the Concentration Field of a Two‐Layer Impinging Stream Mixer
Authors: Zhang Jianwei , He Ziyu , Sha Xinli , Feng Ying , Dong Xin
Published: July 2022

The concentration field of a two‐layer impinging stream mixer was measured by the plane laser‐induced fluorescence (PLIF) technology, and the energy distribution of the concentration field was studied by Hilbert‐Huang transform. The Hilbert spectrum and marginal spectrum under different operational conditions were analyzed in the mixer. It is indicated that the energy of the concentration field firstly increased and then decreased with larger nozzle diameter and nozzle spacing. The energy of the concentration field incremented with the rise of the jet Reynolds number. According to the energy characteristic value Pi, the flow field of the impinging stream mixer was divided into three regions. It could provide a quantitative basis for identification of the flow regimes of impinging steam.
Exploring the Electrochemistry of Iron Dithiolene and Its Potential for Electrochemical Homogeneous Carbon Dioxide Reduction
Authors: Armstrong Craig G. , Potter Mark , Malcomson Thomas , Hogue Ross W. , Armstrong Sapphire M. , Kerridge Andrew , Toghill Kathryn E.
Published: July 2022

In this work, the dithiolene complex iron(III) bis‐maleonitriledithiolene [Fe(mnt)2] is characterised and evaluated as a homogeneous CO2 reduction catalyst. Electrochemically the Fe(mnt)2 is reduced twice to the trianionic Fe(mnt)23− state, which is correspondingly found to be active towards CO2. Interestingly, the first reduction event appears to comprise overlapping reversible couples, attributed to the presence of both a dimeric and monomeric form of the dithiolene complex. In acetonitrile Fe(mnt)2 demonstrates a catalytic response to CO2 yielding typical two‐electron reduction products: H2, CO and CHOOH. The product distribution and yield were governed by the proton source. Operating with H2O as the proton source gave only H2 and CO as products, whereas using 2,2,2‐trifluoroethanol gave 38 % CHOOH faradaic efficiency with H2 and CO as minor products.
Methyl Carbamate‐Lithium Salt Deep Eutectic Electrolyte for Lithium‐Ion Batteries
Authors: Hardin Nathaniel Z. , Duca Zachary , Imel Adam , Ward Patrick A.
Published: July 2022

Deep eutectic electrolytes (DEEs) represent a burgeoning field in electrolytes for energy storage applications. Compared to the more conventionally studied Li‐ion electrolyte systems, these electrolytes offer numerous advantages, such as high ion concentration, costs, lower temperature operation, and safety. In this work, the formation of a novel eutectic electrolyte based on lithium salts and methyl carbamate was reported. These DEEs were formed via mixing lithium salts and low‐cost methyl carbamate at ratios varying from 1 : 2 to 1 : 5 (mol:mol). The DEE formed from methyl carbamate and lithium hexafluorophosphate (LiPF6) at a 1 : 5 molar ratio generated a 4V stability window and a 25 °C conductivity of up to 3.16E−3 S cm−1. The DEE formed from methyl carbamate and lithium bis(trifluoromethane)sulfonimide (LiTFSI) at a 1 : 5 molar ratio generated a 3.2 V stability window and a 25 °C conductivity of up to 2.87E−3 S cm−1. The LiPF6 DEE also demonstrated a discharge capacity of 128 mAh g−1after 50 cycles with 93 % discharge capacity retention at moderate cycling rates of 0.5C in a lithium titanate (LTO)/lithium iron phosphate (LFP) full cell. These results demonstrate the potential for methyl carbamate to generate eutectics from lithium salts and offer alternative electrolytes for use in low‐temperature Li‐ion battery applications.
Zum Glück gibt's Pech
Authors: Sicker Dieter
Published: July 2022

Reisen Sie gern? Oft hat man dabei unerwartete Erlebnisse, die irgendwie mit Chemie zu tun haben und chemisches Lehrbuchwissen wird ungeahnt erweitert. Es verknüpft sich mit Geschichte und Geschichten, unbekannten Anwendungen, praktischen Handgriffen und dem realen Leben anderer Menschen. Über solche kleinen Wunder soll diese Serie berichten. Diesmal begeben wir uns auf eine Reise in Raum und Zeit und staunen, was Baumharz für ein besonderer Stoff ist.
CRISPR/Cas – die vielleicht schärfste Schere der Welt?
Authors: Mittl Maximilian , Rossa Jan , Geue Niklas
Published: July 2022

Die folgende Aufgabe befasst sich mit der Genschere CRISPR/Cas9, die der Fachwelt spätestens seit dem Chemie‐Nobelpreis 2020 bekannt ist. Zunächst werden generelle strukturelle Merkmale von DNA und RNA erläutert, bevor der Einsatz der Genschere veranschaulicht und durch eine kurze Diskussion zum detaillierten Mechanismus der DNA‐Spaltung abgerundet wird.
Sommer, Sonne, Chemie – mit dem Branddreieck lacht das Camperherz
Authors: Endres Wiebke
Published: July 2022

Die Aufzählung „Sommer, Sonne, Chemie“ mag nicht jedem sofort sympathisch, gar passend anmuten, zumal nicht in einer Jahreszeit, in der es uns in die ach so unberührte Natur zieht – von Chemie doch offenbar gar keine Spur. Aber da sind sie, die Camper, die gemütlich am Grill oder Gaskocher sitzend, die Chemie in all ihren Facetten genießen – und das wäre ohne das Branddreieck undenkbar
Pragmatic randomized trial assessing the impact of digital health technology on quality of life in patients with heart failure: Design, rationale and implementation
Authors: Victoria‐Castro Angela M. , Martin Melissa , Yamamoto Yu , Ahmad Tariq , Arora Tanima , Calderon Frida , Desai Nihar , Gerber Brett , Lee Kyoung A. , Jacoby Daniel , Melchinger Hannah , Nguyen Andrew , Shaw Melissa , Simonov Michael , Williams Alyssa , Weinstein Jason , Wilson Francis P.
Published: July 2022

Background

Self‐care and patient engagement are important elements of heart failure (HF) care, endorsed in the guidelines. Digital health tools may improve quality of life (QOL) in HF patients by promoting care, knowledge, and engagement. This manuscript describes the rationale and challenges of the design and implementation of a pragmatic randomized controlled trial to evaluate the efficacy of three digital health technologies in improving QOL for patients with HF.

Hypothesis

We hypothesize that digital health interventions will improve QOL of HF patients through the early detection of warning signs of disease exacerbation, the opportunity of self‐tracking symptoms, and the education provided, which enhances patient empowerment.

Methods

Using a fully electronic enrollment and consent platform, the trial will randomize 200 patients across HF clinics in the Yale New Haven Health system to receive either usual care or one of three digital technologies designed to promote self‐management and provide critical data to clinicians. The primary outcome is the change in QOL as assessed by the Kansas City Cardiomyopathy Questionnaire at 3 months.

Results

First enrollment occurred in September 2021. Recruitment was anticipated to last 6–8 months and participants were followed for 6 months after randomization. Our recruitment efforts have highlighted the large digital divide in our population of interest.

Conclusion

Assessing clinical outcomes, patient usability, and ease of clinical integration of digital technologies will be beneficial in determining the feasibility of the integration of such technologies into the healthcare system.
Laser Capture Microdissection Optimization for High‐Quality RNA in Mouse Brain Tissue
Authors: Nogueira Margareth , Golbert Daiane C. F. , Landeira Bruna , Leão Richardson N.
Published: July 2022

Laser Capture Microdissection (LCM) is a method that allows one to select and dissect well‐defined structures, specific cell subpopulations, or even single cells from different types of tissue for subsequent extraction of DNA, RNA, or proteins. Its precision allows the dissection of specific groups of cells, avoiding unwanted cells. However, despite its efficiency, several steps can affect the sample RNA integrity. RNA instability represents a challenge in the LCM method, and low RNA integrity can introduce biases, as different transcripts often have different degradation rates. Here we describe an optimized protocol to provide good‐concentration and high‐quality RNA from specific structures: dentate gyrus and CA1 in the hippocampus, basolateral amygdala, and anterior cingulate cortex of mouse brain tissue. However, the protocol is applicable to other areas of interest. © 2022 Wiley Periodicals LLC.

Basic Protocol: Laser capture microdissection of mouse brain tissue
Breeding increases grain yield, zinc, and iron, supporting enhanced wheat biofortification
Authors: Govindan Velu , Atanda Sikiru , Singh Ravi P. , Huerta‐Espino Julio , Crespo‐Herrera Leonardo Abdiel , Juliana Philomin , Mondal Suchismita , Joshi Arun K. , Bentley Alison R.
Published: July 2022

Estimation of the rate of genetic gain over time allows quantification of breeding progress. Here we report on the rate of grain yield and zinc (Zn) concentration increase over 11 yr of targeted wheat (Triticum aestivum L.) biofortification breeding at the International Maize and Wheat Improvement Center (CIMMYT). Data from yield trials evaluated across multiple locations in South Asia and beyond showed that average annual increases in grain yield potential of ∼1.5% and 0.9% per year gains for grain Zn and Fe concentrations. Across locations in all countries, mean yields of the five highest‐yielding entries showed an annual gain of 109 kg ha−1 yr−1 in yield and 0.3  mg kg−1 for grain Fe and Zn as well as 0.66 g for the yield component thousand‐grain weight. There was a strong positive correlation between Fe and Zn (r = .42) across locations, whereas no genetic correlation was observed between grain yield and Zn (r = .05) across locations. Despite the slight negative relationship between yield and Zn, through targeted crossing and development of large segregating populations we were able to identify transgressive segregants combining increased yield and Zn concentrations. Significant differences between lines for grain micronutrient concentrations were detected, and significant location effects on grain Zn and Fe concentrations were observed. These results demonstrate that continuous and simultaneous genetic gain for grain yield and concentrations of Fe and Zn is possible in elite spring bread wheat lines with potential to deliver global impact through identification of superior parents for use by national breeding programs and the release of biofortified wheat cultivars.
A new transformerless semi‐quadratic buck–boost converter based on combination of Cuk and traditional buck–boost converters
Authors: Hosseinpour Majid , Ahmadi Mahsa , Seifi Ali , Mousavi‐Aghdam Seyed Reza
Published: July 2022

In this paper, a new transformerless buck–boost converter is proposed. This converter is based on combining two basic converters, including Cuk and traditional buck–boost converters, along with a voltage multiplier (VM) at the output side. The proposed semi‐quadratic buck–boost converter operates in continuous conduction mode (CCM) and provides two operation modes by turning the switches on and off. This converter has some merits such as a wide conversion ratio and continuous input current. The proposed converter consists of two switches with simultaneous operation resulting in simplicity in control. A modular configuration and a wide range of duty cycles are available through the proposed converter, which causes higher or lower output voltage and facilitates the converter maintenance. The calculations of the ideal and the real voltage gain, voltage stress of switches and diodes, efficiency, and design consideration of elements are given in this paper. Finally, a prototype is implemented, and experimental waveforms are obtained to prove and validate the simulation results as well as the theoretical analysis of the proposed converter.
Treg cell abnormality and its potential treatments in patients with primary immune thrombocytopenia
Authors: Ji Lili , Cheng Yunfeng
Published: July 2022

Primary immune thrombocytopenia (ITP) is an autoimmune heterogeneous disorder. T regulatory cells (Treg), play an important role in the pathogenesis of the disease. Numerical and functional disorders of Treg cells were both demonstrated in ITP. Thymocyte output decrease and instability of Treg cells contributed to the lower count of the cells. Several immune deregulatory defects of Treg cells further led to the disease's onset. Restoring Treg cells might have a therapeutic effect on ITP. New options focusing on increasing the number, or enhancing the immunomodulating function of Treg cells was reviewed in this manuscript.
Predicting changes in molluscan spatial distributions in mangrove forests in response to sea level rise
Authors: Ma Wei , Wang Mao , Fu Haifeng , Tang Chaoyi , Wang Wenqing
Published: July 2022

Mollusks are an important component of the mangrove ecosystem, and the vertical distributions of molluscan species in this ecosystem are primarily dictated by tidal inundation. Thus, sea level rise (SLR) may have profound effects on mangrove mollusk communities. Here, we used dynamic empirical models, based on measurements of surface elevation change, sediment accretion, and molluscan zonation patterns, to predict changes in molluscan spatial distributions in response to different sea level rise rates in the mangrove forests of Zhenzhu Bay (Guangxi, China). The change in surface elevation was 4.76–9.61 mm year−1 during the study period (2016–2020), and the magnitude of surface‐elevation change decreased exponentially as original surface elevation increased. Based on our model results, we predicted that mangrove mollusks might successfully adapt to a low rate of SLR (2.00–4.57 mm year−1) by 2100, with mollusks moving seaward and those in the lower intertidal zones expanding into newly available zones. However, as SLR rate increased (4.57–8.14 mm year−1), our models predicted that surface elevations would decrease beginning in the high intertidal zones and gradually spread to the low intertidal zones. Finally, at high rates of SLR (8.14–16.00 mm year−1), surface elevations were predicted to decrease across the elevation gradient, with mollusks moving landward and species in higher intertidal zones blocked by landward barriers. Tidal inundation and the consequent increases in interspecific competition and predation pressure were predicted to threaten the survival of many molluscan groups in higher intertidal zones, especially arboreal and infaunal mollusks at the landward edge of the mangroves, resulting in a substantial reduction in the abundance of original species on the landward edge. Thus, future efforts to conserve mangrove floral and faunal diversity should prioritize species restricted to landward mangrove areas and protect potential species habitats.
Grassland type and seasonal effects have a bigger influence on plant functional and taxonomical diversity than prairie dog disturbances in semiarid grasslands
Authors: Rodriguez‐Barrera Maria Gabriela , Kühn Ingolf , Estrada‐Castillón Eduardo , Cord Anna F.
Published: July 2022

Prairie dogs (Cynomys sp.) are considered keystone species and ecosystem engineers for their grazing and burrowing activities (summarized here as disturbances). As climate changes and its variability increases, the mechanisms underlying organisms' interactions with their habitat will likely shift. Understanding the mediating role of prairie dog disturbance on vegetation structure, and its interaction with environmental conditions through time, will increase knowledge on the risks and vulnerability of grasslands.

Here, we compared how plant taxonomical diversity, functional diversity metrics, and community‐weighted trait means (CWM) respond to prairie dog C. mexicanus disturbance across grassland types and seasons (dry and wet) in a priority conservation semiarid grassland of Northeast Mexico.

Our findings suggest that functional metrics and CWM analyses responded to interactions between prairie dog disturbance, grassland type and season, whilst species diversity and cover measures were less sensitive to the role of prairie dog disturbance. We found weak evidence that prairie dog disturbance has a negative effect on vegetation structure, except for minimal effects on C4 and graminoid cover, but which depended mainly on season. Grassland type and season explained most of the effects on plant functional and taxonomic diversity as well as CWM traits. Furthermore, we found that leaf area as well as forb and annual cover increased during the wet season, independent of prairie dog disturbance.

Our results provide evidence that grassland type and season have a stronger effect than prairie dog disturbance on the vegetation of this short‐grass, water‐restricted grassland ecosystem. We argue that focusing solely on disturbance and grazing effects is misleading, and attention is needed on the relationships between vegetation and environmental conditions which will be critical to understand semiarid grassland dynamics under future climate change conditions in the region.
Distribution and population structure of the smooth‐hound shark, Mustelus mustelus (Linnaeus, 1758), across an oceanic archipelago: Combining several data sources to promote conservation
Authors: Espino Fernando , González José Antonio , Bosch Néstor E. , Otero‐Ferrer Francisco J. , Haroun Ricardo , Tuya Fernando
Published: July 2022

Sharks play a key role in the structure and functioning of marine ecosystems. More ecological information is essential to implement responsible management and conservation actions on this fauna, particularly at a regional level for threatened species. Mustelus mustelus is widely found in the eastern Atlantic Ocean and catalogued as “Vulnerable” by the IUCN European assessment. In this study, data on the distribution and population structure of this species across the islands of the Canarian archipelago, located along an east to west gradient in the north‐eastern Atlantic, were collected by taking advantage of “Local Ecological Knowledge,” in terms of sightings in coastal waters and long‐term imprints on the local gastronomic heritage, and decadal fisheries landings. Both sources of quantitative data (sightings and fisheries landings) demonstrated that adults of M. mustelus has a significantly larger presence in the eastern and central, than in the western islands of the archipelago. This is also reflected on local gastronomic legacies, with a larger number of recipes in the eastern and central islands. Adult smooth‐hound sharks were significantly more observed in sandy and sandy‐rocky bottoms, with individuals seen throughout the entire year, whereas juveniles aggregate on very shallow waters in spring and summer. Such aggregations require a special management strategy, as they play a key role in critical life stages; these sites should be protected from human perturbations. We also suggest a temporal fishing ban between April and October, when individuals tend to concentrate on nearshore waters. Because of the large differences in presence of this shark among the Canary Islands, management of the species should be adapted to the specific peculiarities of each island, rather than adopting a management policy at the entire archipelago‐scale. Overall, this study sets the basis for further investigation to promote conservation of this vulnerable shark in the study region.
Laying low: Rugged lowland rainforest preferred by feral cats in the Australian Wet Tropics
Authors: Bruce Tom , Williams Stephen E. , Amin Rajan , L'Hotellier Felicity , Hirsch Ben T.
Published: July 2022

Invasive mesopredators are responsible for the decline of many species of native mammals worldwide. Feral cats have been causally linked to multiple extinctions of Australian mammals since European colonization. While feral cats are found throughout Australia, most research has been undertaken in arid habitats, thus there is a limited understanding of feral cat distribution, abundance, and ecology in Australian tropical rainforests. We carried out camera‐trapping surveys at 108 locations across seven study sites, spanning 200 km in the Australian Wet Tropics. Single‐species occupancy analysis was implemented to investigate how environmental factors influence feral cat distribution. Feral cats were detected at a rate of 5.09 photographs/100 days, 11 times higher than previously recorded in the Australian Wet Tropics. The main environmental factors influencing feral cat occupancy were a positive association with terrain ruggedness, a negative association with elevation, and a higher affinity for rainforest than eucalypt forest. These findings were consistent with other studies on feral cat ecology but differed from similar surveys in Australia. Increasingly harsh and consistently wet weather conditions at higher elevations, and improved shelter in topographically complex habitats may drive cat preference for lowland rainforest. Feral cats were positively associated with roads, supporting the theory that roads facilitate access and colonization of feral cats within more remote parts of the rainforest. Higher elevation rainforests with no roads could act as refugia for native prey species within the critical weight range. Regular monitoring of existing roads should be implemented to monitor feral cats, and new linear infrastructure should be limited to prevent encroachment into these areas. This is pertinent as climate change modeling suggests that habitats at higher elevations will become similar to lower elevations, potentially making the environment more suitable for feral cat populations.
Solar radiation and soil moisture drive tropical forest understory responses to experimental and natural hurricanes
Authors: Hogan J. Aaron , Sharpe Joanne M. , Van Beusekom Ashley , Stankavich Sarah , Matta Carmona Samuel , Bithorn John E. , Torres‐Díaz Jamarys , González Grizelle , Zimmerman Jess K. , Shiels Aaron B.
Published: July 2022

Tropical forest understory regeneration occurs rapidly after disturbance with compositional trajectories that depend on species availability and environmental conditions. To predict future tropical forest regeneration dynamics, we need a deeper understanding of how pulse disturbance events, like hurricanes, interact with environmental variability to affect understory demography and composition. We examined fern and sapling mortality, recruitment, and community composition in relation to solar radiation and soil moisture using 17 years of forest dynamics data (2003–2019) from the Canopy Trimming Experiment in the Luquillo Experimental Forest, Puerto Rico. Solar radiation increased 150% and soil moisture increased 40% following canopy trimming of experimental plots relative to control plots. All plots were disturbed in 2017 by Hurricanes Irma and Maria, so experimentally trimmed plots presented the opportunity to study the effects of multiple hurricanes, while control plots isolated the effects of a single natural hurricane. Recruitment rates maximized at 0.14 individuals/plot/month for ferns and 0.20 stems/plot/month for saplings. Recruitment and mortality were distributed more evenly over the 17 years of monitoring in experimentally trimmed plots than in control plots; however, following Hurricane Maria demographic rates substantially increased in control plots only. In experimentally trimmed plots, the largest community compositional shifts occurred as a result of the trimming events, and compositional changes were greatest for control plots after Hurricane Maria in 2017. Pioneer tree and fern species increased in abundance in response to both simulated and natural hurricanes. Following Hurricane Maria, two dominant pioneer species, Cyathea arborea and Cecropia schreberiana, recruited abundantly, but only in control plots. In trimmed plots, increased solar radiation and soil moisture shifted understory species composition steadily toward pioneer and secondary‐successional species, with soil moisture interacting strongly with canopy trimming. Thus, both solar radiation and soil moisture are environmental drivers affecting pioneer species recruitment following disturbance, which interact with canopy opening following hurricanes. Our results suggest that if hurricane disturbances increase in frequency and severity, as suggested by climate change predictions, the understory regeneration of late‐successional species, such as Manilkara bidentata and Sloanea berteroana, which prefer deeper shade and slightly drier soil microsites, may become imperiled.
Sedimentary DNA records long‐term changes in a lake bacterial community in response to varying nutrient availability
Authors: Thorpe Amy C. , Anderson Amy , Goodall Tim , Thackeray Stephen J. , Maberly Stephen C. , Bendle James A. , Gweon Hyun S. , Read Daniel S.
Published: July 2022

Microbial communities play important roles in lake ecosystems and are sensitive to environmental change. However, our understanding of their responses to long‐term change such as eutrophication is limited, as long‐term lake monitoring is rare, and traditional paleolimnological techniques (pigments and microfossils) are restricted to a low taxonomic resolution, or organisms with well‐preserved structures. Sedimentary DNA (sedDNA) is a promising technique to reconstruct past microbial communities in sediments, but taphonomic processes and the ability of sedDNA to record bacterial pelagic history accurately are largely unknown. Here, we sequenced the 16S rRNA gene in triplicate sediment cores from Esthwaite Water (English Lake District) which has concurrent long‐term monitoring and observational data. The sediment record spanned 113 years and included an episode of increased nutrient availability from the 1970s, followed by a more recent decline. Trends in bacterial community composition were broadly similar among the three sediment cores. Cyanobacterial richness in the sediment cores correlated significantly with that of cyanobacteria in a 65‐year microscopy‐based monitoring record, and some known pelagic bacterial taxa were detected in the sediment. sedDNA revealed distinct shifts in community composition in response to changing lake physicochemical conditions. The relative abundance of cyanobacteria closely reflected nutrient enrichment, and Proteobacteria, Bacteroidetes, and Verrucomicrobia were relatively more abundant in recent sediments, while Chloroflexi, Firmicutes, Acidobacteria, Nitrospirae, Spirochaetes, and Planctomycetes declined in more recent sediments. Following lake restoration efforts to reduce nutrient enrichment, the relative abundance of cyanobacteria returned to pre‐1970 levels, but the bacterial community did not fully recover from the period of intense eutrophication within the time scale of our study. These results suggest that sedDNA is a valuable approach to reconstruct lake microbial community composition over the 100‐year time scale studied, but an improved understanding of DNA deposition and degradation is required to further the application of sedDNA in paleolimnology.
Use of liver stiffness measurements in acute decompensated heart failure: new applications of a non‐invasive technique
Authors: Dhillon Jaspreet K. , Fong Michael W. , Fong Tse‐Ling
Published: July 2022

Heart failure (HF) is a complex disease associated with multisystem organ failure, recurrent hospital admissions, and increased mortality. Acute decompensated heart failure (ADHF) increases central venous pressure (CVP) with resultant hepatic congestion, and this relationship has prognostic significance. The gold standard method of measuring CVP, right heart catheterization, is invasive and costly, prompting further investigation into more accurate non‐invasive assessments in HF patients, including liver elastography. Liver elastography relies on imaging techniques to assess liver stiffness measurements (LSM), with high values equating to increased stiffness. While this was developed to assess fibrosis in liver disease, LSM also reflect increased CVP and hepatic congestion. Multiple studies involving ADHF patients, find that increased LSM are independently predictive of increased cardiac events, all‐cause mortality, and worse post‐operative outcome after both acute HF exacerbation and left ventricular assist device (LVAD) placement. In this review, we discuss the role of LSM as a surrogate for CVP and their applications in determining prognosis in both the ADHF and LVAD populations.
Myocardial strain for heart failure with preserved ejection fraction but without diastolic dysfunction
Authors: Park Jin Joo , Hwang In‐Chang , Kang Si‐Hyuck , Park Jun‐Bean , Park Jae‐Hyeong , Cho Goo‐Yeong
Published: July 2022

Aims

Some patients with apparent heart failure (HF) have an ejection fraction (EF) ≥ 50% and elevated levels of natriuretic peptides (NPs), but no significant diastolic dysfunction. Among these, some may have HF, others may not. Myocardial strain is an excellent prognostic factor.

Methods and results

Among 4312 consecutive patients with acute HF from three tertiary hospitals, we included 355 patients with EF of ≥50% and elevated levels of NPs, without significant diastolic dysfunction. Patients were classified as having impaired global longitudinal strain (GLS < 16%) or normal GLS (GLS ≥ 16%). The primary endpoint was 5 year all‐cause mortality. The mean age was 70.3 years and 49% were female. Overall, 107 patients (30.1%) died at 5 years. As per the definition, 176 (49.6%) patients had impaired GLS and 179 (50.4%) had normal GLS. Patients with normal GLS had lower 5 year all‐cause mortality than those with impaired GLS (P < 0.001). When comparing with the 11 365 age‐matched and sex‐matched controls, patients with normal GLS had the same long‐term survival as the controls (P = 0.834), whereas those with impaired GLS had 48% increased risk of all‐cause mortality (hazard ratio, 1.48; 95% confidence interval, 1.17–1.89).

Conclusions

Among patients with apparent HF and preserved EF but without diastolic dysfunction, those with impaired GLS may be considered to have HF.
Metal‐Mediated Interactions in Homo‐ and Heterobimetallic Edifices with Lanthanides: A Study in Solution
Authors: Hamacek Josef , Elhabiri Mourad , Le Guennic Boris , Shanzer Abraham , Albrecht‐Gary Anne‐Marie
Published: July 2022

We report here on the coordination properties of a series of lanthanide cations (Ln=La, Nd, Eu, Tb, Er) with a tripodal homoditopic ligand L, which is bearing three diamido‐dihydroxamate arms anchored on a tertiary amine. The complexes of L with lanthanides were studied in a MeOH/H2O (80/20 by weight) solvent and a marked size‐discriminating effect depending on the intramolecular interactions was observed in the tripodal dinuclear lanthanide edifice. Positive cooperative effects favour the formation of the bimetallic LLn2 complexes compared with the monometallic analogues for the heavier lanthanide cations (Eu, Tb, Er), while the lighter ones (La, Nd) show a decrease of cooperative interactions in the corresponding bimetallic species. Moreover, increased levels of heterobimetallic complexes are detected for Ln(III) pairs containing a lighter Ln(III) ion and a heavier one. In contrast with the adjunctive ligand exchange reported for LFe2 and CDTA, the corresponding substitution reaction for LLn2 occurs according to a disjunctive mechanism. Our work thus highlights the importance of the balance between the rigidity of a tripodal structure and the flexibility of the side arms to accommodate two trivalent cations in a supramolecular ensemble.