Simultaneous nitrification and autotrophic denitrification in fluidized bed reactors using pyrite and elemental sulfur as electron donors

In this study, simultaneous nitrification and autotrophic denitrification (SNAD) with either elemental sulfur or pyrite were investigated in fluidized bed reactors in mesophilic conditions. The reactor performance was evaluated at different ammonium (12-40 mg/L of NH4+-N), nitrate (35-45 mg/L of NO3--N), and dissolved oxygen (DO) (0.1-1.5 mg/L) concentrations, with a hydraulic retention time of 12 h. The pyrite reactor supported the SNAD process with a maximum nitrogen removal efficiency of 139.5 mg/(L·d) when the DO concentration was in the range of 0.8-1.5 mg/L. This range, however, limited the denitrification efficiency of the reactor, which decreased from 90.0% ± 5.3% in phases II-V to 67.9% ± 7.2% in phases VI and VII. Sulfate precipitated as iron sulfate (FeSO4/Fe2(SO4)3) and sodium sulfate (Na2SO4) minerals during the experiment. The sulfur reactor did not respond well to nitrification with a low and unstable ammonium removal efficiency, while denitrification occurred with a nitrate removal efficiency of 97.8%. In the pyrite system, the nitrifying bacterium Nitrosomonas sp. was present, and its relative abundance increased from 0.1% to 1.1%, while the autotrophic denitrifying genera Terrimonas, Ferruginibacter, and Denitratimonas dominated the community. Thiobacillus, Sulfurovum, and Trichlorobacter were the most abundant genera in the sulfur reactor during the entire experiment.

Hepatitis C virus resistance to new specifically-targeted antiviral therapy: A public health perspective

Until very recently, treatment for chronic hepatitis C virus(HCV) infection has been based on the combination of two non-viral specific drugs: pegylated interferon-α and ribavirin, which is effective in, overall, about 40%-50% of cases. To improve the response to treatment, novel drugs have been designed to specifically block viral proteins. Multiple compounds are under development, and the approval for clinical use of the first of such direct-acting antivirals in 2011(Telaprevir and Boceprevir), represents a milestone in HCV treatment. HCV therapeutics is entering a new expanding era, and a highly-effective cure is envisioned for the first timesince the discovery of the virus in 1989. However, any antiviral treatment may be limited by the capacity of the virus to overcome the selective pressure of new drugs, generating antiviral resistance. Here, we try to provide a basic overview of new treatments, HCV resistance to new antivirals and some considerations derived from a Public Health perspective, using HCV resistance to protease and polymerase inhibitors as examples.

Experimental bio-artificial liver:Importance of the architectural design on ammonia detoxification performance

AIM To determine the influence of the construction design over the biological component's performance in an experimental bio-artificial liver(BAL) device.METHODS Two BAL models for liver microorgans(LMOs) were constructed. First, we constructed a cylindrical BAL and tested it without the biological component to establish its correct functioning. Samples of blood and biological compartment(BC) fluid were taken after 0, 60, and 120 min of perfusion. Osmolality, hematocrit, ammonia and glucose concentrations, lactate dehydrogenase(LDH) release(as a LMO viability parameter), and oxygen consumption and ammonia metabolizing capacity(as LMO functionality parameters) were determined. CPSI and OTC gene expression and function were measured. The second BAL, a "flat bottom" model, was constructed using a 25 cm2 culture flask while maintaining all other components between the models. The BC of both BALs had the same capacity(approximately 50 cm3) and both were manipulated with the same perfusion system. The performances of the two BALs were compared to show the influence of architecture.RESULTS The cylindrical BAL showed a good exchange of fluids and metabolites between blood and the BC, reflected by the matching of osmolalities, and glucose and ammonia concentration ratios after 120 min of perfusion. No hemoconcentration was detected, the hematocrit levels remained stable during the whole study, and the minimal percentage of hemolysis(0.65% ± 0.10%) observed was due to the action of the peristaltic pump. When LMOs were used as biological component of this BAL they showed similar values to the ones obtained in a Normothermic Reoxygenation System(NRS) for almost all the parameters assayed. After 120 min, the results obtained were: LDH release(%): 14.7 ± 3.1 in the BAL and 15.5 ± 3.2 in the NRS(n = 6); oxygen consumption(μmol/min?g wet tissue): 1.16 ± 0.21 in the BAL and 0.84 ± 0.15 in the NRS(n = 6); relative expression of Cps1 and Otc: 0.63 ± 0.12 and 0.67 ± 0.20, respectively, in the BAL, and 0.86 ± 0.10 and 0.82 ± 0.07, respectively, in the NRS(n = 3); enzymatic activity of CPSI and OTC(U/g wet tissue): 3.03 ± 0.86 and 222.0 ± 23.5, respectively, in the BAL, and 3.12 ± 0.73 and 228.8 ± 32.8, respectively, in the NRS(n = 3). In spite of these similarities, LMOs as a biological component of the cylindrical BAL were not able to detoxify ammonia at a significant level(not detected vs 35.1% ± 7.0% of the initial 1 mM NH4+ dose in NRS, n = 6). Therefore, we built a second BAL with an entirely different design that offers a flat base BC. When LMOs were placed in this "flat bottom"device they were able to detoxify 49.3% ± 8.8% of the initial ammonia overload after 120 min of perfusion(n = 6), with a detoxification capacity of 13.2 ± 2.2 μmol/g wet tissue.CONCLUSION In this work, we demonstrate the importance of adapting the BAL architecture to the biological component characteristics to obtain an adequate BAL performance.

Identification of quantitative trait loci and candidate genes for primary metabolite content in strawberry fruit

Improvement of nutritional and organoleptic quality of fruits is a key goal in current strawberry breeding programs.The ratio of sugars to acids is a determinant factor contributing to fruit liking,although different sugars and acids contribute in varying degrees to this complex trait.A segregating F1 population of 95 individuals,previously characterized for several fruit quality characters,was used to map during 2 years quantitative trait loci(QTL)for 50 primary metabolites,L-ascorbic acid(L-AA)and other related traits such as soluble solid content(SSC),titratable acidity(TA),and pH.A total of 133 mQTL were detected above the established thresholds for 44 traits.Only 12.9%of QTL were detected in the 2 years,suggesting a large environmental influence on primary metabolite content.An objective of this study was the identification of key metabolites that were associated to the overall variation in SSC and acidity.As it was observed in previous studies,a number of QTL controlling several metabolites and traits were co-located in homoeology group V(HG V).mQTL controlling a large variance in raffinose,sucrose,succinic acid,and L-AA were detected in approximate the same chromosomal regions of different homoeologous linkage groups belonging to HG V.Candidate genes for selected mQTL are proposed based on their co-localization,on the predicted function,and their differential gene expression among contrasting F1 progeny lines.RNA-seq analysis from progeny lines contrasting in L-AA content detected 826 differentially expressed genes and identified Mannose-6-phosphate isomerase,FaM6PI1,as a candidate gene contributing to natural variation in ascorbic acid in strawberry fruit.

Biological Corridors as a Connectivity Tool in the Region of the Great American Chaco:Identification of Biodiversity Hotspots in the Ecoregions of the Paraguayan Chaco

This work presents the main biodiversity hotspots existing in the Paraguayan Chaco and is an update of the results obtained in the first Ecoregional Assessment of the Great American Chaco.These are the results of a series of workshops that included scientific and technical discussions carried out by local experts in zoology,botany,forestry,soil science,and hydrogeology applying a biodiversity vision of 25-30 years for the territory,after overlapping the maps of the first assessment with that of the advance of the changes of land use in the territory.Criteria for detecting biodiversity hotspots were discussed,including:permanent and temporary watercourses,other bodies of water such as fresh and salty lagoons,reserve areas of different categories,as well as important bird areas(IBAs),RAMSAR areas and others,which must be connected in the future,combining the production areas with the conservation of biodiversity.

Identification of tree groups used by secondary cavity-nesting birds to simplify forest management in subtropical forests

In tropical and subtropical forest ecosystems,cavities formed by decay processes are a key but scarce resource for birds that nest and roost in them,which makes them a highly sensitive group to logging.The piedmont forest of northwestern Argentina is a complex ecosystem with 113 tree and 120 bird species.It has high logging pressure on the few,well-conserved forest remnants,complicating the delineation of sustainable management guidelines for each tree or bird species in a short time.Our objective was to reduce the complexity of subtropical forests by grouping tree species according to the characteristics used by secondary cavity-nesting birds(i.e.non excavators).In the piedmont forest,50 plots of 0.25 ha were sampled to record cavity trees and cavity characteristics.These were then used in a cluster analysis to form tree groups.Additionally,cavities were searched to identify the bird species using the decay-formed cavities.A total of 187 cavity trees,comprising 23 tree species,were recorded,and these formed four tree groups or clusters.We recorded 86 cavities that were used by secondary cavitynesting bird species.The four tree groups were unequally used by secondary cavity nesters.The tree group that included valuable timber species(Myroxylon peruiferum,Anadenanthera colubrina and Calycophyllum multiflorum)and had the greatest cavity availability represented 71%of total cavity use.Another tree group with valuable timber species(Cedrela balansae and Amburana cearensis),measured>73 cm DBH and>21 m tall,had cavity entrances>0.10 cm2,and contributed 14%of all cavity use by birds.A third group had no highly economically valuable tree species,and included the snag category(i.e.standing dead trees)as well as a 15%of cavity use.The fourth tree group had a DBH<0.40 cm,only one highly economically valuable tree species(Cordia trichotoma),and supported no cavity use.The clustering of subtropical trees can reduce the complexity of these forests,hence easing their management by focusing on those groups with tree species showing similar characteristics and providing suitable nesting sites for secondary cavity-nesting birds.

Development of a Method for Identification and Quantification of Sulfadiazine and Pyrimethamine in Serum of Congenital Toxoplasmosis Pediatric Patients

Infection with Toxoplasma gondii, is one of the most widespread zoonoses in the world. Congenital Toxoplasmosis (CT) is particularly risky due to its fetal complications. Sulfadiazine (SDZ) and Pyrimethamine (PYR) are usually used for CT treatment in Argentina, to prevent morbidity. Due to the lack of commercial pediatric formulations, these must be prepared in the hospital pharmacy. This is the first report of serum concentrations measures in pediatric CT therapy for this combination of drugs. A bioanalytical method was developed for identification and simultaneous quantification of SDZ and PYR by High Performance Liquid Chromatography (HPLC) with UV detection. The validated method was applied to residual serum samples obtained from 6 pediatric patients undergoing treatment with SDZ 42.20 a 93.70 mg/kg/day and PYR 0.77 a 2.70 mg/kg/day. Sample pretreatment consisted on a deproteinization step followed by centrifugation and then injection of supernatant. Limit of Detection (LOD) and Quantification (LOQ) were (0.17 ± 0.02 and 0.13 ± 0.02) μg/mL and (0.46 ± 0.01 and 0.36 ± 0.01) μg/mL for SDZ and PYR respectively, with an appropriate linear range. Concentrations range found were ( - 162.04 ± 0.02) μg/mL for SDZ and ( - 7.30 ± 0.03) μg/mL for PYR. We developed and validated in real pediatric samples, an acute, precise and low-cost method for quantification of SDZ and PYR using a non-sophisticate chromatographic equipment, suitable for hospital therapeutic monitoring for public health system.

Omics-based biomarkers as useful tools in metabolic dysfunctionassociated steatotic liver disease clinical practice:How far are we?

Unmet needs exist in metabolic dysfunction-associated steatotic liver disease(MASLD)risk stratification.Our ability to identify patients with MASLD with advanced fibrosis and at higher risk for adverse outcomes is still limited.Incorporating novel biomarkers could represent a meaningful improvement to current risk predictors.With this aim,omics technologies have revolutionized the process of MASLD biomarker discovery over the past decades.While the research in this field is thriving,much of the publication has been haphazard,often using single-omics data and specimen sets of convenience,with many identified candidate biomarkers but lacking clinical validation and utility.If we incorporate these biomarkers to direct patients’management,it should be considered that the roadmap for translating a newly discovered omics-based signature to an actual,analytically valid test useful in MASLD clinical practice is rigorous and,therefore,not easily accomplished.This article presents an overview of this area’s current state,the conceivable opportunities and challenges of omics-based laboratory diagnostics,and a roadmap for improving MASLD biomarker research.

How to fill the biodiversity data gap:Is it better to invest in fieldwork or curation?

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream results.Understanding how best to fill existing gaps and account for biases is necessary to improve our current information most effectively.Two current main approaches for obtaining and improving data include(1)curation of biological collections,and(2)fieldwork.However,the comparative effectiveness of these approaches in improving biodiversity data remains little explored.We used the Flora de Bogota project to study the magnitude of change in species richness,spatial coverage,and sample coverage of plant records based on curation versus fieldwork.The process of curation resulted in a decrease in species richness(synonym and error removal),but it significantly increased the number of records per species.Fieldwork contributed to a slight increase in species richness,via accumulation of new records.Additionally,curation led to increases in spatial coverage,species observed by locality,the number of plant records by species,and localities by species compared to fieldwork.Overall,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records available in herbaria.We recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with fieldwork.The stepwise strategy would enable fieldwork to be planned more costeffectively given the limited resources for biodiversity exploration and characterization.

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind electricity.In the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing oxygen.Moreover,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different processes.The first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary membrane.Thanks to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be adjusted.Here,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 NmL min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric power.Finally,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried out.ODHE reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

Arsenite provides a selective signal that coordinates arsenate uptake and detoxification through the regulation of PHR1 stability in Arabidopsis

In nature,plants acquire nutrients from soils to sustain growth,and at the same time,they need to avoid the uptake of toxic compounds and/or possess tolerance systems to cope with them.This is particularly challenging when the toxic compound and the nutrient are chemically similar,as in the case of phosphate and arsenate.In this study,we demonstrated that regulatory elements of the phosphate starvation response(PSR)coordinate the arsenate detoxification machinery in the cell.We showed that arsenate repression of the phosphate transporter PHT1;1 is associated with the degradation of the PSR master regulator PHR1.Once arsenic is sequestered into the vacuole,PHR1 stability is restored and PHT1;1 expression is recovered.Furthermore,we identified an arsenite responsive SKP1-like protein and a PHR1 interactor F-box(PHIF1)as constituents of the SCF complex responsible for PHR1 degradation.We found that arsenite,the form to which arsenate is reduced for compartmentalization in vacuoles,represses PHT1;1 expression,providing a highly selective signal versus phosphate to control PHT1;1 expression in response to arsenate.Collectively,our results provide molecular insights into a sensing mechanism that regulates arsenate/phosphate uptake depending on the plant’s detoxification capacity.

Molecular mechanisms underlying SARS-CoV-2 hepatotropism and liver damage

In coronavirus disease 2019(COVID-19),severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)primarily targets the respiratory system,but evidence suggests extrapulmonary organ involvement,notably in the liver.Viral RNA has been detected in hepatic tissues,and in situ hybridization revealed virions in blood vessels and endothelial cells.Electron microscopy confirmed viral particles in hepatocytes,emphasizing the need for understanding hepatotropism and direct cytopathic effects in COVID-19-related liver injury.Various factors contribute to liver injury,including direct cytotoxicity,vascular changes,inflammatory responses,immune reactions from COVID-19 and vaccinations,and druginduced liver injury.Although a typical hepatitis presentation is not widely documented,elevated liver biochemical markers are common in hospitalized COVID-19 patients,primarily showing a hepatocellular pattern of elevation.Long-term studies suggest progressive cholestasis may affect 20%of patients with chronic liver disease post-SARS-CoV-2 infection.The molecular mechanisms underlying SARS-CoV-2 infection in the liver and the resulting liver damage are complex.This“Editorial”highlights the expression of the Angiotensin-converting enzyme-2 receptor in liver cells,the role of inflammatory responses,the impact of hypoxia,the involvement of the liver's vascular system,the infection of bile duct epithelial cells,the activation of hepatic stellate cells,and the contribution of monocyte-derived macrophages.It also mentions that pre-existing liver conditions can worsen the outcomes of COVID-19.Understanding the interaction of SARS-CoV-2 with the liver is still evolving,and further research is required.

Middle Eocene chondrichthyan fauna from Antarctic Peninsula housed in the Museo de La Plata,Argentina

In recent years,the taxonomy and systematics of the cartilaginous fish taxa from the Eocene La Meseta Formation of Seymour(Marambio)Island,Antarctica have been extensively discussed in a series of papers,resulting in a complete revision of the Antarctic Eocene ichthyofauna housed in the Vertebrate Paleontology collection of the Museo de La Plata,Argentina.This collection constitutes one of the largest and taxonomically most diverse in the world,with approximately 20000 specimens,which provides a solid database used for the analysis of qualitative and quantitative chondrichthyan taxonomic composition.The information provided herein might be useful to understand the sudden decline in chondrichthyan taxonomic diversity towards the top of La Meseta Formation as well as its potential relationship with environmental changes during the Eocene.

Review of the Cretaceous avian diversity of Antarctica:a changing scenario for the evolution of early Neornithine birds

The worldwide record of Cretaceous Neornithes and Neornithine-like birds is both controversial and poorly understood.However,in recent years,the Antarctic continent has yielded a substantial number of Maastrichtian avian specimens,contributing significantly to our understanding of the early evolution of this group.Simultaneously,the keen interest and collaborative efforts of various paleornithologists have resulted in a wealth of knowledge,which we have thoroughly reviewed,updated,and discussed in the context of recent discoveries.

Perilipin 2 inhibits replication of hepatitis B virus deoxyribonucleic acid by regulating autophagy under high-fat conditions

Hepatitis B virus(HBV)infection poses a global health concern without a definitive cure;however,antiviral medications can effectively suppress viral replication.This study delves into the intricate interplay between lipid metabo-lism and HBV replication,implicating molecular mechanisms such as the stearoyl coenzyme A desaturase 1 autophagy pathway,SAC1-like phosphatidylinositol phosphatase,and galectin-9 mediated selective autophagy of viral core proteins in regulating HBV replication.Within lipid droplets,perilipin 2(PLIN2)emerges as a pivotal guardian,with its overexpression protecting against autophagy and downregulation stimulating triglyceride catabolism through the autophagy pathway.This editorial discusses the correlation between hepatic steatosis and HBV replication,emphasizing the role of PLIN2 in this process.The study underscores the multifaceted roles of lipid metabolism,autophagy,and perilipins in HBV replication,shedding light on potential therapeutic avenues.

Differential Expression of Genes Related to Fruit Development and Capsaicinoids Synthesis in Habanero Pepper Plants Grown in Contrasting Soil Types

Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives them industrial importance.Soil is an important factor that affects pepper development,nutritional quality,and capsaicinoid content.However,the effect of soil type on fruit development and capsaicinoid metabolism has been little understood.This work aimed to compare the effect of soils with contrasting characteristics,black soil(BS)and red soil(RS),on the expression of genes related to the development of fruits,and capsaicinoid synthesis using a transcriptomic analysis of the habanero pepper fruits.Plants growing in RS had bigger fruits and higher expression of genes related to floral development,fruit abscission,and softening which suggests that RS stimulates fruit development from early stages until maturation stages.Fruits from plants growing in BS had enrichment in metabolic pathways related to growth,sugars,and photosynthesis.Besides,these fruits had higher capsaicinoid accumulation at 25 days post-anthesis,and higher expression of genes related to the branched-chain amino acids metabolism(ketol-acid reductisomerase KARI),pentose phosphate pathway and production of NADPH(glucose-6-phosphate-1-dehydrogenase G6PDH),and proteasome and vesicular traffic in cells(26S proteasome regulatory subunit T4 RPT4),which suggest that BS is better in the early stimulation of pathways related to the nutritional quality and capsaicinoid metabolism in the fruits.

小胶质细胞在卒中中的作用

小胶质细胞在缺血后的炎症反应和受损组织的清除中扮演关键角色,它们对缺血引起的干扰反应迅速,致力于恢复失去的稳态。然而,被修改的环境,包括离子失衡、关键的神经元-小胶质细胞相互作用的中断、去极化传播以及来自坏死神经元的危险信号的产生,诱导了小胶质细胞的形态和表型转变。这导致它们表现为促炎表型并增加吞噬活动。从缺血后的第3天开始,巨噬细胞渗透到坏死组织核心,而小胶质细胞则在病灶周边聚集。此外,炎症促使代谢转向有利于糖酵解、戊糖磷酸途径和脂质合成。这些转变与吞噬脂质的摄入相结合,促进了脂滴生成、合成代谢,并使小胶质细胞增殖。增殖的小胶质细胞释放营养因子,有助于神经保护和修复。然而,一些小胶质细胞持续积累脂质,并转变为功能失调且可能有害的泡沫细胞。研究还表明,有些小胶质细胞要么清除凋亡细胞能力的受损,要么消除突触、活神经元或内皮细胞。然而,阐明被吞噬细胞的生存能力、局部环境特征、组织损伤程度和时间序列将是至关重要的。缺血为小胶质细胞提供了丰富多样的、依赖于区域和损伤的刺激,随着时间演变导致出现不同的小胶质细胞表型,包括表现为促炎性或功能失调特征的细胞,以及显示出促进修复功能的细胞。准确分析小胶质细胞表型,以及更精确地了解相关的缺血后组织条件,是对卒中进行针对性干预的必要步骤。

Assessing the Performance of a Dynamical Downscaling Simulation Driven by a Bias-Corrected CMIP6 Dataset for Asian Climate

In this study,we aim to assess dynamical downscaling simulations by utilizing a novel bias-corrected global climate model(GCM)data to drive a regional climate model(RCM)over the Asia-western North Pacific region.Three simulations were conducted with a 25-km grid spacing for the period 1980–2014.The first simulation(WRF_ERA5)was driven by the European Centre for Medium-Range Weather Forecasts Reanalysis 5(ERA5)dataset and served as the validation dataset.The original GCM dataset(MPI-ESM1-2-HR model)was used to drive the second simulation(WRF_GCM),while the third simulation(WRF_GCMbc)was driven by the bias-corrected GCM dataset.The bias-corrected GCM data has an ERA5-based mean and interannual variance and long-term trends derived from the ensemble mean of 18 CMIP6 models.Results demonstrate that the WRF_GCMbc significantly reduced the root-mean-square errors(RMSEs)of the climatological mean of downscaled variables,including temperature,precipitation,snow,wind,relative humidity,and planetary boundary layer height by 50%–90%compared to the WRF_GCM.Similarly,the RMSEs of interannual-tointerdecadal variances of downscaled variables were reduced by 30%–60%.Furthermore,the WRF_GCMbc better captured the annual cycle of the monsoon circulation and intraseasonal and day-to-day variabilities.The leading empirical orthogonal function(EOF)shows a monopole precipitation mode in the WRF_GCM.In contrast,the WRF_GCMbc successfully reproduced the observed tri-pole mode of summer precipitation over eastern China.This improvement could be attributed to a better-simulated location of the western North Pacific subtropical high in the WRF_GCMbc after GCM bias correction.

A new look at the first dinosaur discovered in Antarctica:reappraisal of Antarctopelta oliveroi(Ankylosauria:Parankylosauria)

The first dinosaur discovered in the Antarctic continent was the ankylosaur Antarctopelta oliveroi in the 1980s.Nevertheless,since then several hypotheses of phylogenetical relationships have been proposed because these have been depended on how the skeletal remains have been interpreted.The main obstacle for clarifying its phylogenetic position is that many portions of the skeleton remain unknown,in addition to the presence of unknown characters in typical ankylosaurs.Considered an ankylosaurid,nodosaurid,or even a chimaera,a recent proposal based on mostly complete material of a new ankylosaur from Chilean Patagonia provided support for a novel phylogenetic hypothesis:Antarctopelta and other southern ankylosaurs are an early branching clade,the Parankylosauria,whose origin probably dates to the Late Jurassic.In the light of this new view,a redescription of the available skeletal remains is provided together with a new reconstruction of the first Antarctic dinosaur known to the science community.

Nitrate reduction capacity of the oral microbiota is impaired in periodontitis:potential implications for systemic nitric oxide availability

The reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity(NRC)and, therefore, nitric oxide availability has not been evaluated. The current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitratereducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals(P < 0.05 in all five datasets with n = 20–82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. The oral NRC was determined in vitro by incubating saliva with 8 mmol/L nitrate(a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment(P < 0.05) but recovered to healthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria(P < 0.01). No significant effect of periodontal treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.