bluuebunny/crossref_metadata_2025 huggingface dataset:
Poloxamer 407 and Hyaluronic Acid Thermosensitive Hydrogel-Encapsulated Ginsenoside Rg3 to Promote Skin Wound Healing
Authors: Peng Xiaojuan , Ding Chuanbo , Zhao Yingchun , Hao Mingqian , Liu Wencong , Yang Min , Xiao Fengyan , Zheng Yinan
Published: July 2022

Ginsenoside Rg3 has shown beneficial effects in various skin diseases. The current interest in designing and developing hydrogels for biomedical applications continues to grow, inspiring the further development of drug-loaded hydrogels for tissue repair and localized drug delivery. The aim of the present study was to develop an effective and safe hydrogel (Rg3-Gel), using ginsenoside Rg3, and we evaluated the wound-healing potential and therapeutic mechanism of Rg3-Gel. The results indicated that the optimized Rg3-Gel underwent discontinuous phase transition at low and high temperatures. Rg3-Gel also exhibited good network structures, swelling water retention capacity, sustainable release performance, and excellent biocompatibility. Subsequently, the good antibacterial and antioxidant properties of Rg3-Gel were confirmed by in vitro tests. In full-thickness skin defect wounded models, Rg3-Gel significantly accelerated the wound contraction, promoted epithelial and tissue regeneration, and promoted collagen deposition and angiogenesis. In addition, Rg3-Gel increased the expression of autophagy proteins by inhibiting the MAPK and NF-KB pathways in vivo. It simultaneously regulated host immunity by increasing the abundance of beneficial bacteria and the diversity of the wound surface flora. From these preliminary evaluations, it is possible to conclude that Rg3-Gel has excellent application potential in wound-healing drug delivery systems.
Passive and Active Microrheology for Biomedical Systems
Authors: Mao Yating , Nielsen Paige , Ali Jamel
Published: July 2022

Microrheology encompasses a range of methods to measure the mechanical properties of soft materials. By characterizing the motion of embedded microscopic particles, microrheology extends the probing length scale and frequency range of conventional bulk rheology. Microrheology can be characterized into either passive or active methods based on the driving force exerted on probe particles. Tracer particles are driven by thermal energy in passive methods, applying minimal deformation to the assessed medium. In active techniques, particles are manipulated by an external force, most commonly produced through optical and magnetic fields. Small-scale rheology holds significant advantages over conventional bulk rheology, such as eliminating the need for large sample sizes, the ability to probe fragile materials non-destructively, and a wider probing frequency range. More importantly, some microrheological techniques can obtain spatiotemporal information of local microenvironments and accurately describe the heterogeneity of structurally complex fluids. Recently, there has been significant growth in using these minimally invasive techniques to investigate a wide range of biomedical systems bothin vitroandin vivo. Here, we review the latest applications and advancements of microrheology in mammalian cells, tissues, and biofluids and discuss the current challenges and potential future advances on the horizon.
Interventions to Decrease Carotid-Intima Media Thickness in Children and Adolescents With Type 1 Diabetes: A Systematic Review and Meta-Analysis
Authors: Epure Adina Mihaela , Anker Daniela , Di Bernardo Stefano , da Costa Bruno R. , Sekarski Nicole , Chiolero Arnaud
Published: July 2022

Introduction

Hyperglycemia is associated with a higher cardiovascular risk, as evidenced by increased carotid-intima media thickness (CIMT) in youth with diabetes. We conducted a systematic review and meta-analysis to assess the effect of pharmacological or non-pharmacological interventions on CIMT in children and adolescents with prediabetes or diabetes.

Methods

We conducted systematic searches of MEDLINE, EMBASE, and CENTRAL, together with supplementary searches in trial registers and other sources for studies completed up to September 2019. Interventional studies assessing ultrasound CIMT in children and adolescents with prediabetes or diabetes were considered for inclusion. Where appropriate, data were pooled across studies using random-effect meta-analysis. Quality was assessed using The Cochrane Collaboration’s risk-of-bias tool and a CIMT reliability tool.

Results

Six studies involving 644 children with type 1 diabetes mellitus were included. No study involved children with prediabetes or type 2 diabetes. Three randomized controlled trials (RCTs) evaluated the effects of metformin, quinapril, and atorvastatin. Three non-randomized studies, with a before-and-after design, evaluated the effects of physical exercise and continuous subcutaneous insulin infusion (CSII). The mean CIMT at baseline ranged from 0.40 to 0.51 mm. The pooled difference in CIMT was -0.01 mm (95% CI: -0.04 to 0.01) for metformin compared to placebo (2 studies; 135 participants; I2: 0%). The difference in CIMT was -0.01 mm (95% CI: -0.03 to 0.01) for quinapril compared to placebo (1 study; 406 participants). The mean change from baseline in CIMT was -0.03 mm (95% CI: -0.14 to 0.08) after physical exercise (1 study; 7 participants). Inconsistent results were reported for CSII or for atorvastatin. CIMT measurement was rated at a higher quality on all reliability domains in 3 (50%) studies. The confidence in results is limited by the low number of RCTs and their small sample sizes, as well as the high risk of bias in before-and-after studies.

Conclusions

Some pharmacological interventions may decrease CIMT in children with type 1 diabetes. However, there is great uncertainty with respect to their effects and no strong conclusions can be drawn. Further evidence from larger RCTs is required.

Systematic Review Registration

PROSPERO, CRD42017075169
Utilization Patterns and Outcomes of People With Diabetes and COVID-19: Evidence From United States Medicare Beneficiaries in 2020
Authors: Austin Andrea M. , Leggett Christopher G. , Schmidt Peter , Bolin Paul , Nelson Eugene C. , Oliver Brant J. , King Ashleigh C.
Published: July 2022

Objective

Determine differences in utilization patterns, disease severity, and outcomes between patients with and without diabetes mellitus diagnosed with COVID-19 in 2020

Research Design and Methods

We used an observational cohort comprised of Medicare fee-for-service beneficiaries with a medical claim indicating a COVID-19 diagnosis. We performed inverse probability weighting between beneficiaries with and without diabetes to account for differences in socio-demographic characteristics and comorbidities.

Results

In the unweighted comparison of beneficiaries, all characteristics were significantly different (P<0.001). Beneficiaries with diabetes were younger, more likely to be black, had more comorbidities, higher rates of Medicare-Medicaid dual-eligibility, and were less likely to be female. In the weighted sample, hospitalization rates for COVID-19 among beneficiaries with diabetes was higher (20.5% vs 17.1%; p < 0.001). Outcomes of hospitalizations were similarly worse among beneficiaries with diabetes: admissions to ICU during hospitalizations (7.78% vs. 6.11%; p < 0.001); in-hospital mortality (3.85% vs 2.93%; p < 0.001); and ICU mortality (2.41% vs 1.77%). Beneficiaries with diabetes had more ambulatory care visits (8.9 vs. 7.8, p < 0.001) and higher overall mortality (17.3% vs. 14.9%, p < 0.001) following COVID-19 diagnosis.

Conclusion

Beneficiaries with diabetes and COVID-19 had higher rates of hospitalization, ICU use and overall mortality. While the mechanism of how diabetes impacts the severity of COVID-19 may not be fully understood, there are important clinical implications for persons with diabetes. A diagnosis of COVID-19 leads to greater financial and clinical burden than for their counterparts, persons without diabetes, including perhaps most significantly, higher death rates.
Energy Metabolism on Mitochondrial Maturation and Its Effects on Cardiomyocyte Cell Fate
Authors: Persad Kaya L. , Lopaschuk Gary D.
Published: July 2022

Alterations in energy metabolism play a major role in the lineage of cardiomyocytes, such as the dramatic changes that occur in the transition from neonate to newborn. As cardiomyocytes mature, they shift from a primarily glycolytic state to a mitochondrial oxidative metabolic state. Metabolic intermediates and metabolites may have epigenetic and transcriptional roles in controlling cell fate by increasing mitochondrial biogenesis. In the maturing cardiomyocyte, such as in the postnatal heart, fatty acid oxidation increases in conjunction with increased mitochondrial biogenesis driven by the transcriptional coregulator PGC1-α. PGC1-α is necessary for mitochondrial biogenesis in the heart at birth, with deficiencies leading to postnatal cardiomyopathy. While stem cell therapy as a treatment for heart failure requires further investigation, studies suggest that adult stem cells may secrete cardioprotective factors which may regulate cardiomyocyte differentiation and survival. This review will discuss how metabolism influences mitochondrial biogenesis and how mitochondrial biogenesis influences cell fate, particularly in the context of the developing cardiomyocyte. The implications of energy metabolism on stem cell differentiation into cardiomyocytes and how this may be utilized as a therapy against heart failure and cardiovascular disease will also be discussed.
Electrochemical Sensor for Hydrogen Peroxide Based on Prussian Blue Electrochemically Deposited at the TiO2-ZrO2–Doped Carbon Nanotube Glassy Carbon-Modified Electrode
Authors: Fernández Lenys , Alvarez-Paguay Jocelyne , González Gema , Uribe Rafael , Bolaños-Mendez Diego , Piñeiros José Luis , Celi Luis , Espinoza-Montero Patricio J.
Published: July 2022

In this investigation, a hydrogen peroxide (H2O2) electrochemical sensor was evaluated. Prussian blue (PB) was electrodeposited at a glassy carbon (GC) electrode modified with titanium dioxide– and zirconia-doped functionalized carbon nanotubes (TiO2.ZrO2-fCNTs), obtaining the PB/TiO2.ZrO2-fCNTs/GC-modified electrode. The morphology and structure of the nanostructured material TiO2.ZrO2-fCNTs was characterized by transmission electron microscopy, the specific surface area was determined via Brunauer–Emmett–Teller, X-ray diffraction, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The electrochemical properties were studied by cyclic voltammetry and chronoamperometry. Titania-zirconia nanoparticles (5.0 ± 2.0 nm) with an amorphous structure were directly synthesized on the fCNT walls, aged during periods of 20 days, obtaining a well-dispersed distribution with a high surface area. The results indicated that the TiO2.ZrO2-fCNT–nanostructured material exhibits good electrochemical properties and could be tunable by enhancing the modification conditions and method of synthesis. Covering of the nanotubes with TiO2-ZrO2 nanoparticles is one of the main factors that affected immobilization and sensitivity of the electrochemical biosensor. The electrode modified with TiO2-ZrO2 nanoparticles with the 20-day aging time was superior regarding its reversibility, electric communication, and high sensitivity and improves the immobilization of the PB at the electrode. The fabricated sensor was used in the detection of H2O2 in whey milk samples, presenting a linear relationship from 100 to 1,000 μmol L−1 between H2O2 concentration and the peak current, with a quantification limit (LQ) of 59.78 μmol L−1 and a detection limit (LD) of 17.93 μmol L−1.
Effect of Light Treatment on Chemical Composition of Andrographis paniculata Seedlings
Authors: Jiang Zhehui , Wang Tianhao , Zhang Kaixue , Zhang Meiqi , Ma Ling , Ren Weichao , Bao Yihong , Ma Wei
Published: July 2022

Light quality consists of a spectrum of different bands, which not only affects plant, development, and primary metabolism but also affects the secondary metabolism of plants. It is an important factor affecting the content of active components of medicinal plants. The A. paniculata seedlings planted in the laboratory, as materials, were tested with red light, far red light, blue light, and ultraviolet light separately. The study assays the content of six main chemical components separately by LC-MS, observes the changes in the content, and analyzes the relationship between the light quality and the active ingredient of A. paniculata. Using the ointment yield and pH value, the fingerprint analysis method of A. paniculata standard decoction was established, and we discussed the selection of index components of A. paniculata standard decoction. It was suggested to select andrographolide as the index component. It will provide a theoretical basis for the large area cultivation of A. paniculata and optimize the quality of medicinal materials to ensure the quality of standard decoction.
Sex-Specific Modulation of the Host Transcriptome in the Spleen of Schistosoma mansoni-Infected Mice
Authors: Winkelmann Franziska , Rabes Anne , Reinholdt Cindy , Koslowski Nicole , Koczan Dirk , Reisinger Emil C. , Sombetzki Martina
Published: July 2022

Background

Schistosomiasis is a severe parasitic disease that is primarily driven by the host’s immune response to schistosome eggs trapped in tissue and by the granulomatous inflammatory and fibrotic reaction they cause. Despite significant progress in understanding the complex immunological processes involved in the relationship between schistosomes and their host, neither an effective vaccine against the infection nor anti-fibrotic drugs currently exists, making the search for new targets for schistosome drugs and vaccine candidates even more important. In order to identify new molecular targets for defense against or elimination of the parasite, we investigate herein the interplay between the host and male or female schistosomes, clearly separating this from the action of the parasite eggs.

Methods

For this purpose, we infected 6–8-week-old female NMRI mice with 100 male (M), female (F), or both (MF)S. mansonicercariae and performed a comparative transcriptomic and flow cytometric analysis of their spleens.

Results

Principal component analysis of a total of 22,207 transcripts showed a clear clustering of the experimental groups. We identified a total of 1,293 genes in group M, 512 genes in group F, and 4,062 genes in group MF that were differentially expressed compared to naive controls. The highest percentage of regulated genes (2,972; 65.9%) was found in group MF alone, but there was a large overlap between groups M and MF (798; 17.7%) and a small overlap between groups F and MF (91; 2.0%). Only 4.5% of genes (201) were revealed to be regulated in all experimental groups (M/F/MF). In addition, we were able to show that both worm sexes trigger immune responses in an egg-independent manner (non-polarized Th1 and Th2 response), with female worms exerting less regulatory influence than males.

Conclusion

Our data show that adult schistosomes trigger sex-specific, egg-independent immune responses. The lists of genes regulated by adult female or male worms presented here may be useful in deciphering host–parasite interactions to identify targets for schistosome elimination.
Untangling an AGS Outbreak Caused by the Recombinant GII.12[P16] Norovirus With Nanopore Sequencing
Authors: Xiong Qianling , Jiang Huimin , Liu Zhe , Peng Jinju , Sun Jing , Fang Ling , Li Caixia , Qiu Ming , Zhang Xin , Lu Jing
Published: July 2022

For a rapidly spreading virus such as NoV (norovirus), pathogen identification, genotype classification, and transmission tracing are urgent for epidemic control. Here, we applied the Nanopore metatranscriptomic sequencing to determine the causative pathogen of a community AGS (Acute gastroenteritis) outbreak. The results were also confirmed by RT-PCR. The NGS (Next Generation Sequencing) library was constructed within 8 hours and sequence analyses were carried out in real-time. NoV positive reads were detected in 13 of 17 collected samples, including two water samples from sewage treatment tank and cistern. A nearly complete viral genome and other genome fragments could be generated from metatranscriptomic sequencing of 13 samples. The NoV sequences from water samples and cases are identical suggesting the potential source of the outbreak. The sequencing results also indicated the outbreak was likely caused by an emerging recombinant GII.12[P16] virus, which was only identified in the United States and Canada in 2017–2018. This is the first report of this emerging variant in mainland China, following the large outbreaks caused by the recombinant GII.17[P17] and GII.2[P16] in 2014 and 2016, respectively. Closely monitoring of the prevalence of this recombinant strain is required. Our data also highlighted the importance of real-time sequencing in emerging pathogens’ surveillance.
Linguistic Dominance and Translanguaging: Language Issues in Generations: The Legacy
Authors: Aiseng Kealeboga
Published: July 2022

The use of language(s) in media is very important as it can determine inclusion or exclusion. As such, the use of language in the media is contentious. This paper traces two language issues in one of the SABC's longest-running soap operas,Generations: The Legacy, language ideology and a tool against that language ideology. The former refers to a linguistic dominance of isiZulu and the latter refers to translanguaging. With the use of transcription data analysis and audio-visual analysis, the current study has concluded that there are issues of linguistic dominance and translanguaging inGenerations: The Legacy. These language issues are perpetuated through the narrative and characters of the story. The appropriate theoretical framework for this paper is the use of language in popular culture, with the view that the use of languages in popular culture can exclude and include, can empower, and disempower. Focusing on the dialogues of the soap using selected episodes as case studies for analysis, the study has also concluded that creative decisions made in the soap are ideological. These findings raise questions about the use of media to perpetuate certain language ideologies and raise questions about whose interests are served by these language ideologies and how to fight these language ideologies.
CT-Based Analysis of Left Ventricular Hemodynamics Using Statistical Shape Modeling and Computational Fluid Dynamics
Authors: Goubergrits Leonid , Vellguth Katharina , Obermeier Lukas , Schlief Adriano , Tautz Lennart , Bruening Jan , Lamecker Hans , Szengel Angelika , Nemchyna Olena , Knosalla Christoph , Kuehne Titus , Solowjowa Natalia
Published: July 2022

Background

Cardiac computed tomography (CCT) based computational fluid dynamics (CFD) allows to assess intracardiac flow features, which are hypothesized as an early predictor for heart diseases and may support treatment decisions. However, the understanding of intracardiac flow is challenging due to high variability in heart shapes and contractility. Using statistical shape modeling (SSM) in combination with CFD facilitates an intracardiac flow analysis. The aim of this study is to prove the usability of a new approach to describe various cohorts.

Materials and Methods

CCT data of 125 patients (mean age: 60.6 ± 10.0 years, 16.8% woman) were used to generate SSMs representing aneurysmatic and non-aneurysmatic left ventricles (LVs). Using SSMs, seven group-averaged LV shapes and contraction fields were generated: four representing patients with and without aneurysms and with mild or severe mitral regurgitation (MR), and three distinguishing aneurysmatic patients with true, intermediate aneurysms, and globally hypokinetic LVs. End-diastolic LV volumes of the groups varied between 258 and 347 ml, whereas ejection fractions varied between 21 and 26%. MR degrees varied from 1.0 to 2.5. Prescribed motion CFD was used to simulate intracardiac flow, which was analyzed regarding large-scale flow features, kinetic energy, washout, and pressure gradients.

Results

SSMs of aneurysmatic and non-aneurysmatic LVs were generated. Differences in shapes and contractility were found in the first three shape modes. Ninety percent of the cumulative shape variance is described with approximately 30 modes. A comparison of hemodynamics between all groups found shape-, contractility- and MR-dependent differences. Disturbed blood washout in the apex region was found in the aneurysmatic cases. With increasing MR, the diastolic jet becomes less coherent, whereas energy dissipation increases by decreasing kinetic energy. The poorest blood washout was found for the globally hypokinetic group, whereas the weakest blood washout in the apex region was found for the true aneurysm group.

Conclusion

The proposed CCT-based analysis of hemodynamics combining CFD with SSM seems promising to facilitate the analysis of intracardiac flow, thus increasing the value of CCT for diagnostic and treatment decisions. With further enhancement of the computational approach, the methodology has the potential to be embedded in clinical routine workflows and support clinicians.
A Bibliometric Analysis of Reactive Oxygen Species Based Nanotechnology for Cardiovascular Diseases
Authors: Liang Yun , Liao Shenjie , Zhang Xiaoshen
Published: July 2022

Cardiovascular diseases (CVDs) continue to be the leading cause of health problems around the world. Because of its unique properties, reactive oxygen species (ROS)-based nanotechnology offers novel solutions to the diagnosis and treatment of CVDs. In order to identify and further promote the development of ROS-based nanotechnology in CVDs, we here provide a bibliometric analysis. 701 eligible articles about the ROS–based nanotechnology for CVD up to May 26th, 2022, were taken from the Web of Science Core Collection database. The VOSviewer was used to analyze annual publications, countries/institutions, funding agencies, journals and research category, and the research hotspots. From the publication of the first article in 2005 to 2021, the output and the number of citations of articles are on the rise. Based on the bibliometric analysis, we found that the current research focuses on the correlation between diagnosis (sensors and), treatment (oxidative stress, inflammation, and drug delivery) and safety (toxicity). Since 2019, research on nanomedicine and drug delivery has become a hotspot. So, more research in chemistry, materials, biology, and medicine is required to further develop and construct ROS-based nanomaterials.
Chlorine-36 Surface Exposure Dating of Late Holocene Moraines and Glacial Mass Balance Modeling, Monte Sierra Nevada, South-Central Chilean Andes (38°S)
Authors: Price Brittany N. , Stansell Nathan D. , Fernández Alfonso , Licciardi Joseph M. , Lesnek Alia J. , Muñoz Ariel , Sorensen Mary K. , Jaque Castillo Edilia , Shutkin Tal , Ciocca Isabella , Galilea Ianire
Published: July 2022

The development of robust chronologies of Neoglaciation from individual glaciers throughout the high-altitude Andes can provide fundamental knowledge of influences such as regional temperature and precipitation variability, and aid in predicting future changes in the Andean climate system. However, records of Late Holocene glaciation from the Central Chilean Andes are sparse, and often poorly constrained. Here, we present 36Cl surface exposure ages, dendrochronologic constraints, and glacial mass balance modeling simulations of Late Holocene glacier fluctuations in the Central-South Chilean Andes. A series of concentric moraine ridges were identified on Monte Sierra Nevada (38°S), where exposure dating of basaltic boulders was used to establish a chronology of ice recession. We infer that moraine abandonment of the most distal ridge in the valley commenced by ∼4.2 ka, and was followed by glacier margin retreat to an up-valley position. Exposure ages of the oldest Late Holocene boulders (∼2.5–0.8 ka) along the marginal extents of the moraine complex indicate fluctuations of the glacier terminus prior to ∼0.65 ka. A final expansion of the ice margin reoccupied the position of the 4.2 ka moraine, with abatement from the outermost composite moraine occurring by ∼0.70 ka, as constrained by tree-ring data from live Araucaria araucana trees. Finally, a series of nested moraines dating to ∼0.45–0.30 ka, formed from a pulsed ice recession during the latest Holocene when the lower reaches of the glacial snout was most likely debris mantled. A distributed temperature index model combined with a glacier flow model was used to quantify an envelope of possible climatic conditions of Late Holocene glaciation. The glacial modeling results suggest conditions were ∼1.5°C colder and 20% wetter during peak Neoglaciation relative to modern conditions. These records also suggest a near-coeval record of Late Holocene climate variability between the middle and high southern latitudes. Furthermore, this study presents some of the youngest 36Cl exposure ages reported for moraines in the Andes, further supporting this method as a valuable geochronologic tool for assessing Late Holocene landscape development.
Tree-Ring Isotopic Records Suggest Seasonal Importance of Moisture Dynamics Over Glacial Valleys of the Central Himalaya
Authors: Singh Nilendu , Shekhar Mayank , Parida Bikash Ranjan , Gupta Anil K. , Sain Kalachand , Rai Santosh K. , Bräuning Achim , Singh Charkaborty Joyeeta , Sharma Vikram , Kamal Tiwari Reet , Chauhan Pankaj , Montagnani Leonardo
Published: July 2022

Accelerated glacier mass loss is primarily attributed to greenhouse-induced global warming. Land–climate interactions have increasingly been recognized as an important forcing at the regional-local scale, but the related effects on the Himalayan glaciers are less explored and thought to be an important factor regulating spatial heterogeneity. The aim of the present study is a multi-decadal approximation of glacier—hydroclimate interaction over the western region of the central Himalaya (WCH). Multi-species, highly coherent, tree-ring cellulose δ18O chronologies from three sites across the WCH were used to derive atmospheric humidity (Atmospheric Moisture Content: AMC) record of the last four centuries. Annual-scale AMC reconstruction implies a decreasing regional atmospheric moisture since the mid-19th century and a sharp decline in recent decades (1960s). Coherency analyses between regional AMC and glacier mass balance (GMB) indicate an abrupt phase-shift in the relationship after the 1960s within a common record of the last 273 years. To ascertain the cause of this phase-shift, annual AMC was disintegrated into seasonal-scale, utilizing ∼200 years of δ18O record of a deciduous tree species. Seasonal (winter: October–March; summer: April–September) AMC reconstructions and disaggregation results indicate higher sensitivity of regional ice-mass variability to winter moisture dynamics than summer.Winter season AMC reconstruction confirms a revival of winter westerlies-driven moisture influx in the region since the 1970 s. Meanwhile, the record for the summer season AMC indicates a gradual decline in moisture influx from the beginning of the 20th century. Interestingly, despite a prominent decline in Indian summer monsoon (ISM) precipitation after the mid-20th century, the summer season AMC—GMB relation remained stable. We hypothesize that decadal-scale greening, and consequently increased evapotranspiration and pre-monsoon precipitation might have been recycled through the summer season, to compensate for the ISM part of precipitation. However, isotope-enabled ecophysiological models and measurements would strengthen this hypothesis. In addition, high-resolution radiative forcing and long-term vegetation greening trends point towards a probable influence of valley greening on GMB. Our results indicate that attribution of ice mass to large-scale dynamics is likely to be modulated by local vegetation changes. This study contributes to the understanding of long-term hydroclimate—ice mass variability in the central Himalaya, where predictions are crucial for managing water resources and ecosystems.
Moment Tensor Solutions for Earthquakes in the Southern Korean Peninsula Using Three-Dimensional Seismic Waveform Simulations
Authors: Song Jung-Hun , Kim Seongryong , Rhie Junkee , Park Donghee
Published: July 2022

Precise estimates of earthquake source properties are crucial for understanding earthquake processes and assessing seismic hazards. Seismic waveforms can be affected not only by individual event properties, but from the Earth’s interior heterogeneity. Therefore, for accurate constraints on earthquake source parameters, the effects of three-dimensional (3D) velocity heterogeneity on seismic wave propagation need evaluation. In this study, regional moment tensor solutions for earthquakes around the southern Korean Peninsula were constrained based on the spectral-element moment tensor inversion method using a recently developed high-resolution regional 3D velocity model with accurate high-frequency waveform simulations. Located at the eastern margin of the Eurasian plate, the Korean Peninsula consists of complex geological units surrounded by thick sedimentary basins in oceanic areas. It exhibits large lateral variations in crustal thickness (> 10 km) and seismic velocity (>10% dlnVs) at its margins in the 3D model. Seismic waveforms were analyzed from regional earthquakes with local magnitudes > 3.4 that occurred within and around the peninsula recorded by local broadband arrays. Moment tensor components were inverted together with event locations using the numerically calculated Fréchet derivatives of each parameter at periods ≥ 6 s. The newly determined solutions were compared with the results calculated from the one-dimensional (1D) regional velocity model, revealing a significant increase in a double-couple component of > 20% for earthquakes off of the coastal margins. Further, compared to initial solutions, ≤ 5 km change in depth was observed for earthquakes near the continental margin and sedimentary basins. The combination of a detailed 3D crustal model and accurate waveform simulations led to an improved fit between data and synthetic seismograms. Accordingly, the present results provide the first confirmation of the effectiveness of using 3D velocity structures for accurately constraining earthquake source parameters and the resulting seismic wave propagation in this region. We suggest that accurate 3D wave simulations, together with improved source mechanisms, can contribute a reliable assessment of seismic hazards in regions with complex continental margin structures and sedimentary basins from offshore earthquakes whose seismic waveforms can be largely affected by 3D velocity structures.
Small-Signal Distributed Frequency Modeling and Analysis for Grid-Forming Inverter-Based Power Systems
Authors: Qi Xiaojing , Zheng Jianyong , Mei Fei
Published: July 2022

More and more renewable energy sources are integrated into power grids, leading to a power electronic-based low-inertia power system. The grid-forming (GFM) inverter is an effective method for improving the inertia of the system. However, with the increased GFM inverters in the system, how the multiple control parameters affect the frequency response is still not clear. In this study, first, the power-phase model of the power grid is established; then, a small-signal distributed frequency model of the GFM inverter-based power system is established associating with the power-phase model of the power grid and the power-frequency model of the GFM inverter. Based on the proposed model, the influence of the multiple parameters to the frequency response is analyzed. It is concluded that both the inertia and damping coefficient affect the settling time, overshoot, and oscillation of the frequency. Finally, the simulation results verify the proposed model and the conclusion.
3D Corona Discharge Model and Its Use in the Presence of Wind During a Thunderstorm
Authors: Guo Xiufeng , Ji Ziyu , Gao Yue , Ding Jie , Zhang Ling
Published: July 2022

In this study, the authors developed a three-dimensional (3D) numerical model for the diffusion of positive corona charges based on a 2D model with a uniform grid to explore the characteristics of corona discharge at a building tip during a thunderstorm in the presence of wind. The variable-grid meshing method is used to solve the problems of implementing a large simulation domain for thunder clouds (kilometer-scale) and the minute calculations of corona discharge at the tip (centimeter scale) in the 3D numerical simulation. The proposed model has advantages in terms of the acquisition of the parameters of corona charges and the spatial distribution of the electric field (E-field) in the environment. We used positive corona discharge at the tip of a building under a negative thunderstorm, along with three wind fields (horizontal wind, updraft, and downdraft with wind speeds of 10 m/s) as an example. The presence of the wind increased the density of corona charges at the tip, where the horizontal wind was the most beneficial for its occurrence. Moreover, the characteristics of distortion of the electric field around the tip were significantly different, owing to the different directions of the wind. Downdraft led to the maximum enhancement in the E-field above the tip, and updraft prompted the minimum increase in it, by only 1.19 times. However, the opposite results were obtained for the enhancement in the spatial range of the charges: The updraft led to the greatest increase in it, and the downdraft caused the smallest. Corona charges had an apparent shielding effect on the E-field below the tip and can even change the polarity of the E-field in a small area close to it. The strongest shielding effect on the ground E-field occurred in the case of the downdraft, which decreased the E-field to 0.36 times compared with that without the corona charges. On the contrary, corona discharge had the weakest shielding ability on the ground when it met the updraft. The horizontal wind had the largest range of shielding on the ground, of up to 14,699.36 m2, while the updraft had the lowest, at only 6,170.91 m2.
Olfactory Inspection of Female Reproductive States in Chimpanzees
Authors: Jänig Susann , Kücklich Marlen , Kulik Lars , Zetzsche Madita , Weiß Brigitte M. , Widdig Anja
Published: July 2022

In mammalian species, olfactory cues are important for within and between species communication. These cues can be part of multimodal signals indicating, for example, female fertility potentially perceived by male conspecifics. However, a large gap exists in our understanding of multimodal signaling in non-human catarrhines. Chimpanzees (Pan troglodytes) live in fission-fusion societies, mate promiscuously and express high levels of male-male competition. Females show a striking visual signal, an exaggerated sexual swelling, known to be a proxy of ovulation, while the maximum swelling is not matching the exact time of ovulation. The question remains if males use additional olfactory cues when being able to approach females closely. This would allow males to pinpoint the exact timing of ovulation and could be one reason why high-ranking males sire offspring more successfully than other males. Here, we present the first systematic test of such multimodal signaling by investigating male sniffing behavior directed to females in relation to their fertility in a group of 13 captive chimpanzees. Our results show that male sniffing behavior significantly increased with female swelling size, with female age as well as when fewer male competitors were present. Hence, odors might be part of a multimodal fertility cue, supporting the idea that males monitor both visual and olfactory cues to gain comprehensive information on female fertility.
Life and Death of Termite Colonies, a Decades-Long Age Demography Perspective
Authors: Chouvenc Thomas , Ban Paul M. , Su Nan-Yao
Published: July 2022

A eusocial insect colony represents a complex biological entity that must ensure degrees of perennity once it reaches maturity (production of dispersing imagoes over many successive years) to optimize its reproductive success. It is known that a subterranean termite colony invests differentially in different castes over time and adjusts colony functions depending on colony internal and external conditions over many years of activity. However, the current study demonstrates that Coptotermes formosanus Shiraki field mature colonies go through dramatic demographic changes and breeding structure shifts, even many years after they have reached reproductive success. By analyzing the changes in age demography of C. formosanus colonies from four field sites, we here provide a new perspective on how a colony may function over decades, which reveals that each colony demographic trajectory is unique. In a way, throughout its life, a termite colony displays its own “demographic individuality” that drives its growth, its foraging ability, its competitiveness, its age demography, its senescence and ultimately its death. This study is therefore a narrated story of the life -and death- of different C. formosanus field colonies over decades of observation.
The Amazon Epiphyte Network: A First Glimpse Into Continental-Scale Patterns of Amazonian Vascular Epiphyte Assemblages
Authors: Quaresma Adriano , Zartman Charles E. , Piedade Maria T. F. , Wittmann Florian , Jardim Mario A. G. , Irume Mariana V. , Benavides Ana M. , Freitas Leandro , Toledo José J. , Boelter Carlos R. , Obermüller Flávio , Duque Alvaro J. , Klein Viviane P. , Mari Maikel L. G. , Schöngart Jochen , Arenas Edith , Pos Edwin T. , Vasco Alejandra , Ek Renske , Plantenga Faline D. M. , Duivenvoorden Joost F. , Biesmeijer Koos , Bender Irene M. A. , ter Steege Hans
Published: July 2022

Epiphytes are still an understudied plant group in Amazonia. The aim of this study was to identify distributional patterns and conservation priorities for vascular epiphyte assemblages (VEA) across Amazonia. We compiled the largest Amazonian epiphyte plot database to date, through a multinational collaborative effort of 22 researchers and 32 field sites located across four Amazonian countries – the Amazonian Epiphyte Network (AEN). We addressed the following continental-scale questions by utilizing the AEN database comprising 96,448 epiphyte individuals, belonging to 518 vascular taxa, and growing on 10,907 tree individuals (phorophytes). Our objectives here are, first, to present a qualitative evaluation of the geographic distribution of the study sites and highlight regional lacunae as priorities for future quantitative inventories. Second, to present the floristic patterns for Amazonia-wide VEA and third, to combine multivariate analyses and rank abundance curves, controlled by major Amazonian habitat types, to determine how VEA vary geographically and ecologically based on major Amazonian habitat types. Three of the most striking patterns found are that: (1) VEA are spatially structured as floristic similarity decays with geographic distance; (2) a core group of 22 oligarchic taxa account for more than a half of all individuals; and (3) extensive floristic sampling gaps still exist, mainly across the highly threatened southern Amazonian deforestation belt. This work represents a first step toward unveiling distributional pattern of Amazonian VEA, which is important to guide future questions on ecology and species distribution ranges of VEA once the collaborative database grows allowing a clearer view of patterns.
CCR5 as a Prognostic Factor in Lower-Grade Glioma is Involved in the Remodeling of the Tumor Microenvironment
Authors: Wang Fang , Tao Zhennan , Tian Zhen , Jin Jiaqi , Dong Jiawei , Dai Yuxiang , Yu Wanli , Tang Bin , Hu Shaoshan
Published: July 2022

Background: Lower-grade gliomas (LGGs) carry a high risk of malignant transformation, leading to severe neurologic deterioration and ultimately, death. The tumor microenvironment (TME) plays an essential role in tumor maintenance, progression, and immunotherapy resistance. Therefore, the LGG TME deserves comprehensive exploration for a novel therapeutic target.

Methods: The ESTIMATE algorithm was used to estimate infiltrating stromal and immune cells of LGG patients obtained from the Cancer Genome Atlas (TCGA) database. Kaplan–Meier analysis was performed to classify survival differences. TME-related differentially expressed genes were identified between the low- and high-immune/stromal groups. Hub genes were screened by constructing protein–protein interaction networks and performing the Cox regression analysis. Differential analysis, survival analysis, gene set enrichment analysis, and clinical relevance analysis specific to hub genes were evaluated by using the TCGA and the Chinese Glioma Genome Atlas datasets, and the results were validated by qRT-PCR, Western blotting, and immunohistochemistry in tissues from LGG patients.

Results: The immune and stromal components in TME were negatively related to patient prognosis. Differentially expressed genes sharing immune score and stromal score were mainly involved in the immune response. C-C chemokine receptor type 5 (CCR5), as only a hub gene, was significantly higher in LGG patients than normal patients and negatively correlated with the prognosis of patients. High-expression CCR5 was positively related to immune-related and tumor progression pathways. CCR5 protein expression was higher in LGG with isocitrate dehydrogenase wildtype. Validated results showed that CCR5 was upregulated in LGG tissues at mRNA and protein levels and could affect immune cell infiltration. These results suggested that CCR5 was a potential indicator for the status of TME.

Conclusion: Glioma cells remodel the immune microenvironment through the high expression of CCR5 and lead to a poor prognosis in patients with LGG. The inhibition of CCR5 may contribute to the efficacy of LGG immunotherapy.
Apoptosis-Related Gene-Mediated Cell Death Pattern Induces Immunosuppression and Immunotherapy Resistance in Gastric Cancer
Authors: Yuan Xiaolu , Zhou Jun , Zhou Liping , Huang Zudong , Wang Weiwei , Qiu Jiasheng , Yang Qiangbang , Zhang Chaohao , Ma MingHui
Published: July 2022

Background: Apoptosis is a type of cell death, which can produce abundant mediators to modify the tumor microenvironment. However, relationships between apoptosis, immunosuppression, and immunotherapy resistance of gastric cancer (GC) remain unclear.

Methods: Gene expression data and matching clinical information were extracted from TCGA-STAD, GSE84437, GSE34942, GSE15459, GSE57303, ACRG/GSE62254, GSE29272, GSE26253, and IMvigor210 datasets. A consensus clustering analysis based on six apoptosis-related genes (ARGs) was performed to determine the molecular subtypes, and then an apoptosisScore was constructed based on differentially expressed and prognostic genes between molecular subtypes. Estimate R package was utilized to calculate the tumor microenvironment condition. Kaplan-Meier analysis and ROC curves were performed to further confirm the apoptosisScore efficacy.

Results: Based on six ARGs, two molecular subgroups with significantly distinct survival and immune cell infiltration were identified. Then, an apoptosisScore was built to quantify the apoptosis index of each GC patient. Next, we investigated the correlations between the clinical characteristics and apoptosisScore using logistic regression. Multivariate Cox analysis shows that low apoptosisScore was an independent predictor of poor overall survival in TCGA and ACRG datasets, and was associated with the higher pathological stage. Meanwhile, low apoptosisScore was associated with higher immune cell, higher ESTIMATEScore, higher immuneScore, higher stromalScore, higher immune checkpoint, and lower tumorpurity, which was consistent with the “immunity tidal model theory”. Importantly, low apoptosisScore was sensitive to immunotherapy. In addition, GSEA indicated that several gene ontology and Kyoto Encyclopedia of Genes and Genomes items associated with apoptosis, several immune-related pathways, and JAK–STAT signal pathway were considerably enriched in the low apoptosisScore phenotype pathway.

Conclusion: Our findings propose that low apoptosisScore is a prognostic biomarker, correlated with immune infiltrates, and sensitivity to immunotherapy in GC.
ACTIVATE-2: A Double-Blind Randomized Trial of BCG Vaccination Against COVID-19 in Individuals at Risk
Authors: Tsilika Maria , Taks Esther , Dolianitis Konstantinos , Kotsaki Antigone , Leventogiannis Konstantinos , Damoulari Christina , Kostoula Maria , Paneta Maria , Adamis Georgios , Papanikolaou Ilias , Stamatelopoulos Kimon , Bolanou Amalia , Katsaros Konstantinos , Delavinia Christina , Perdios Ioannis , Pandi Aggeliki , Tsiakos Konstantinos , Proios Nektarios , Kalogianni Emmanouela , Delis Ioannis , Skliros Efstathios , Akinosoglou Karolina , Perdikouli Aggeliki , Poulakou Garyfallia , Milionis Haralampos , Athanassopoulou Eva , Kalpaki Eleftheria , Efstratiou Leda , Perraki Varvara , Papadopoulos Antonios , Netea Mihai G. , Giamarellos-Bourboulis Evangelos J.
Published: July 2022

In a recent study of our group with the acronym ACTIVATE, Bacillus Calmete-Guérin (BCG) vaccination reduced the occurrence of new infections compared to placebo vaccination in the elderly. Most benefit was found for respiratory infections. The ACTIVATE-2 study was launched to assess the efficacy of BCG vaccination against coronavirus disease 2019 (COVID-19). In this multicenter, double-blind trial, 301 volunteers aged 50 years or older were randomized (1:1) to be vaccinated with BCG or placebo. The trial end points were the incidence of COVID-19 and the presence of anti–severe acute respiratory syndrome coronavirus 2 (anti–SARS-CoV-2) antibodies, which were both evaluated through 6 months after study intervention. Results revealed 68% relative reduction of the risk to develop COVID-19, using clinical criteria or/and laboratory diagnosis, in the group of BCG vaccine recipients compared with placebo-vaccinated controls, during a 6-month follow-up (OR 0.32, 95% CI 0.13-0.79). In total, eight patients were in need of hospitalization for COVID-19: six in the placebo group and two in the BCG group. Three months after study intervention, positive anti–SARS-CoV-2 antibodies were noted in 1.3% of volunteers in the placebo group and in 4.7% of participants in BCG-vaccinated group. The ACTIVATE II trial did not meet the primary endpoint of the reduction of the risk for COVID-19 3 months after BCG vaccination; however, the secondary endpoint of the reduction of the risk for COVID-19 6 months after BCG vaccination was met. BCG vaccination may be a promising approach against the COVID-19 pandemic.