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ICP-MS Based Metallomics and GC-MS Based Metabolomics Reveals the Physiological and M...
Zhaojian Wang
Jing Wu

Zhaojian Wang

and 12 more

June 15, 2022
To improve the growth, yield and quality of Dendrobium huoshanense, Fe 3O 4 NPs has been used as nano-fertilizer. Safety of Fe 3O 4 NPs in medicinal production on D. huoshanense must be critically evaluated. In this study, two-year-old D. huoshanense was cultured in a solution containing Fe 3O 4 NPs (100 or 200 mg/L) for 21 days. The results were investigated by a combination of phenotypic and non-target metabolomics based on gas chromatography-mass spectrometry (GC-MS). Fe 3O 4 NPs induced not only earlier flowering and increased sugar content, photosynthesis, but also stress to plants, increased MDA content and related antioxidant enzymes activities. Fe 3O 4 NPs caused a significant Fe and some other nutrient elements (Mn, Co, B, Mo) accumulation in stems based in Inductively Coupled Plasma Mass Spectrometry analysis. Metabolomics revealed that the metabolites were reprogrammed in D. huoshanense by Fe 3O 4 NPs exposure. Fe 3O 4 NPs can inhibit antioxidant defense-related pathways, suggesting that Fe 3O 4 NPs had the antioxidant ability with plants accumulating relative metabolites to cope with stresses. As the first study associating Fe 3O 4 NPs with the quality of D. huoshanense, it provided vital insights into the molecular mechanisms of how D. huoshanense responds to Fe 3O 4 NPs, ensuring the reasonable use of Fe 3O 4 NPs as nano-fertilizer.
Intraoperative Ventricular Septal Rupture: A Case Report
Hannah Rando
Ahmet Kilic

Hannah Rando

and 1 more

June 15, 2022
Ventricular septal rupture (VSR) is a rare complication of myocardial infarction that requires surgical repair. Herein we describe a case of intraoperative VSR requiring a second bypass run and patch repair. This case highlights the importance of early reperfusion and poses concern for delayed patient presentation during the COVID-19 pandemic.
Utilization of two- and three-dimensional transesophageal echocardiography in success...
Zeyad Elmarzouky
Ming-Chon Hsiung

Zeyad Elmarzouky

and 9 more

June 15, 2022
Background. The presence of thrombus in the left atrial appendage (LAA) and/or LA body has so far been considered a contraindication to the transcatheter mitral valve (MV) in bioprosthetic MV/ MV annuloplasty ring implantation. Objective. The aim of this study is to describe, for the first time to our knowledge, the utilization of both two-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE) in successfully performing without any embolic or other complications transcatheter MV in bioprosthetic MV/ mitral ring implantation using the apical approach in a group of 12 patients (pts) with co-existing LAA and/or LA body thrombus. Patients, Methods and Results. All pts were severely symptomatic with severe bioprosthetic MV stenosis in 9, severe native MV stenosis with a previous surgically inserted MV annuloplasty ring in 1 and severe MV regurgitation secondary to bioprosthetic cusp rupture in 2 pts. Thrombus in the LAA and/ or LA body was noted in all pts by 2D and 3DTEE. All pts were at high or prohibitive risk for surgery and all refused surgery. Utilizing both 2D and 3DTEE, especially 3DTEE, the guidewires and the prosthesis deployment system could be manipulated under direct vision through the MV bioprosthesis into the LA and left superior pulmonary vein bypassing and avoiding any contact with the thrombus. The transcatheter procedure was successfully accomplished in all patients with relief of stenosis/ regurgitation and amelioration of symptoms with no embolic or other complications during the procedure and over a mean follow-up period of 21 months. Conclusion. Our small study demonstrates the feasibility of successfully performing transcatheter MV in bioprosthetic MV/ MV annuloplasty ring procedure in pts with thrombus in LAA and/or LA body without any embolic or other complications.
A Computational study of MgmHn nanoclusters with n:m ≥ 2:1 for efficient hydrogen sto...
Dongjie Shi
Youxuan Ni

Dongjie Shi

and 6 more

June 15, 2022
Magnesium-based hydrogen storage material (MgH2) has attracted much attention due to its high hydrogen storage density (7.6 wt%). However, the high hydrogen dissociation enthalpy and slow hydrogen dissociation rate in bulk Mg hinder its wide application in the efficient hydrogen storage. In the present work, we study the hydrogen adsorption and desorption reactions of MgmHn (m = 1-6) nanoclusters using density functional theory (DFT). From the global search for the configurations of MgmHn nanoclusters, we found not only stable saturated MgmHn (n = 2m) nanoclusters, but four hydrogen-enriched MgmHn (n:m>2:1) nanoclusters, Mg3H7, Mg4H9, Mg5H11, Mg6H13, with the hydrogen storage density higher than 8.3 wt%. The electronic-structure calculations indicate that the stability of the hydrogen-enriched cluster gets relatively higher for larger nanocluster. The ab initio dynamics simulations shows that all hydrogen-enriched clusters have very fast hydrogen dissociation rates, which is promising for the hydrogen dissociation at ambient temperature and pressure. This work provides insights into the hydrogen storage mechanism of nano-magnesium materials.
Inferior Vena Cava Thrombosis attributable to Hyperhomocysteinemia: A Case Report fro...
Ramesh Acharya
Astika Shrestha

Ramesh Acharya

and 6 more

June 15, 2022
Inferior vena cava thrombosis (IVCT) is a rare occurrence and is a result of leg deep vein thrombosis (DVT). The etiology of IVC thrombosis can be divided into congenital versus acquired etiological factors found in Virchow’s triad of stasis, injury, and hypercoagulability. Hyperhomocysteinemia is a rare risk factor for thromboembolism.
Exploring electonic Structure and Spectral Properties of Nitrogen-Doped Boron Cluster...
Cheng-Hong Deng
Zheng-wen Long

Cheng-Hong Deng

and 3 more

June 15, 2022
For a better understanding the effects of nitrogen atom doping on boron clusters, we investigated adopting the ABCluster global search technique and CALYPSO approach combined with density functional theory the lowest energy structures, bonding, electrons delocalization and spectral properties of neutral nitrogen-doped boron clusters, the size of which varies from 10 to 20. The results of its calculations are displayed the global minimum of these clusters are plane or quasi plane structures at n= 11, 13, 15-20, the bowl-like structures at n= 10, 12 and the boat-shaped structure at n=14. It is found that B20N is most stable of all structures. Natural population analysis (NPA) indicates that boron atoms sectional electrons transfer to doped nitrogen atoms. Electron localization Orbital Function (LOL) and Electron Localization Function (ELF) analysis indicate there are strong covalent bonds between doped N atons and B atoms for clusters BnN(n=10-20). In addition, under the same isosurface, the isosurface of B10N is the thickest, indicating that it has the most electrons and the strongest delocalization. Infrared and Raman spectra show that clusters BnN(n=10-20) have a great deal of characteristic peaks, and the strongest IR peaks and Raman peaks are situated at different positions, which can be used to identify the clusters structures and make comparative analysis with future experiments. Electronic absorption spectrum analysis shows that the first absorption peak of these clusters is located in the visible band. The study provides theoretical guidance and basis for the development of novel boron-based nanomaterials.
Distinct ecological mechanisms drive the spatial scaling patterns of abundant and rar...
Qichao Tu
Xia Liu

Qichao Tu

and 3 more

June 15, 2022
Revealing the ecological mechanisms driving the diversity patterns followed by microbial communities across space and through time is an essential issue in microbial community ecology. In this study, two typical spatial scaling patterns, including diversity-area and distance-decay relationships, were investigated for microbial communities in an ocean sediment ecosystem. Strong spatial scaling patterns were observed at the whole community level and for the rare subcommunities, but hardly for the abundant subcommunities. Rare subcommunities were mainly responsible for the observed spatial scaling patterns, as also confirmed by extending spatial scaling diversity metrics to Hill numbers. Distinct ecological mechanisms underlay the differed spatial scaling patterns followed by abundant and rare subcommunities. Both environmental heterogeneity and local community assembly mechanisms drove the microbial spatial scaling patterns. Environmental heterogeneity was significantly associated with the spatial scaling metrics of rare but not abundant subcommunities. Strong ecological drift and dispersal limitation underlay the spatial scaling patterns of rare subcommunities, whereas high homogeneous selection weakened the spatial scaling patterns of abundant subcommunities. Such differed mechanisms driving the spatial scaling patterns of abundant and rare subcommunities were also experimentally confirmed by deep sequencing experiments. This study links microbial spatial scaling patterns with ecological mechanisms, providing novel mechanistic insights into the diversity patterns followed by different types of microbes.
On extended partial (fuzzy) strong k-metric spaces
YAOQIANG WU

YAOQIANG WU

June 15, 2022
In this paper, we introduce a new notion of extended partial strong k-metric spaces with controlled operators and provide some examples to show that is different from extended k-metric spaces which initiated by Kamran et al. Furthermore, we introduce the concept of extended partial fuzzy strong k-metric spaces with controlled operators, which is a generalization of extended k-metric in the sense of Mehmood given. Finally, we establish fixed point theorems for self-mappings which satisfy Banach contraction principle on extended partial fuzzy strong k-metric spaces. Also, we provide some examples to illustrate our results.
Synchronization analysis chaos of fractional derivatives chaotic satellite systems vi...
sanjay kumar
Chandrashekhar Nishad

sanjay kumar

and 3 more

June 15, 2022
In this research article, a new fractional derivative chaotic satellite system is presented. Nature of different fractional derivative (order) satellite systems with phase portrait analysis versus parameters are analysed through utilization of the fractional calculus in computational simulation. Phase portrait analysis of fractional derivatives of the different satellite systems is drawn and tabled with various parameters values. In new fractional derivative satellite systems, chaos is existed in less than 3D (dimensional) satellite systems. The results are validated by the different tools:- equilibrium points, dissipative, Lyapunov exponents and bifurcation diagrams. Feedback and active control techniques for controlling chaos synchronization of new fractional derivative satellite systems are achieved.
The High-Voltage Level Shifter with dV/dt noises Shielding
Jianwen Cao
Ze-kun Zhou

Jianwen Cao

and 2 more

June 15, 2022
This paper proposes a HV (high-voltage) level shifter to shield the dV/dt noise. When there is the dV/dt noises, the proposed level shifter’s output is locked by the dV/dt noise shielding circuit. So, the proposed level shifter has infinite dV/dt immunity, which is not affected by the supply voltage, and processes. In the 0.5µm BCD process, the proposed level shifter is simulated, realizing the ±250V/ns dV/dt noises shielding function and less than 1.5ns delay time under the 400V HV power supply.
Reverse left ventricular remodeling with left bundle branch area pacing in heart fail...
Noppachai Siranart
Ronpichai Chokesuwattanaskul

Noppachai Siranart

and 8 more

June 15, 2022
Background: Left bundle branch area pacing (LBBAP) has recently become a promising option for the near-natural restoration of electrical activation. However, the clinical relevance of therapeutic effects in individuals with heart failure with reduced ejection fraction (HFrEF) and dyssynchrony remains unknown. Methods & Results: MEDLINE, EMBASE, and Cochrane databases were searched from inception until June 2022. Data from each study was combined using a random-effects model, the generic inverse variance method of DerSimonian and Laird, to calculate standard mean differences and pooled incidence ratio, with 95% confidence intervals (CI). A total of 772 HFrEF patients were analyzed from 15 observational studies per protocol. The success rate of LBBAP implantation was 94.8% (95% CI 89.9 to 99.6, I2 = 79.4%), which was strongly correlated with shortening QRS duration after LBBAP implantation, with a mean difference of −48.10 msec (95% CI −60.16 to −36.05, I2 = 96.7%). Over a period of 6–12 months of follow-up, pacing parameters were stable over time. There were significant improvements in left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic diameter (LVEDD), and left ventricular end-diastolic volume (LVEDV) with mean difference of 16.38% (95% CI 13.13 to 19.63 I2 = 90.2 %), −46.23 mL (95% CI −63.17 to −29.29, I2 = 86.82%), −7.21 mm (95% CI −9.71 to −4.71, I2 = 84.6%), and −44.52 mL (95% CI −64.40 to −24.64, I2 = 85.9 %), respectively . Conclusions: LBBAP was associated with improvements in both cardiac function and electrical synchrony. The benefits of LBBAP in individuals with HFrEF and dyssynchrony should be further validated by randomized studies.
Efficacy and safety of axillary vein puncture real-time guided by roadmap fluoroscopy...
Qiying Chen
Bangwei Wu

Qiying Chen

and 5 more

June 15, 2022
Objective: Roadmap fluoroscopy has never previously been evaluated for axillary vein puncture in clinical practice. Our retrospective cohort study was performed to investigate the efficacy and safety of axillary vein puncture real-time guided by roadmap fluoroscopy in cardiac pacemaker implantation. Methods and Results: A total of 178 patients undergoing axillary vein puncture in permanent pacemaker implantation were included in the present cohort study during a 1-year period at our institution. All procedures were performed by the operators with previous experience in axillary approach. Primary endpoint was defined as axillary vein success rate. Secondary endpoints were venous access site change, time to obtain venous access, procedural time, and complication rate. For the primary outcomes, a higher success rate was observed in the roadmap group compared with the blind puncture group (95.2% vs 78.7%; P<0.001), as well as a lower rate of venous access site change (7.1% vs 35.1%; P <0.001) and shorter time to obtain venous access and procedural time, with lower complications (3.6 % vs 6.4 %; P<0.01). Conclusion: The roadmap fluoroscopy real-time guided axillary venous access is safer and has a better success rate and faster execution time compared with the blind axillary puncture in cardiac pacemaker implantation. However, further larger scale prospective randomized controlled trials are required to confirm the findings.
Impact of Anticoagulation Therapy on the Cognitive Decline and Dementia in Patients w...
Thomas Bunch
Heidi May

Thomas Bunch

and 10 more

June 15, 2022
Background: Atrial fibrillation (AF) is associated with a risk for cognitive impairment and dementia, which is more pronounced in patients with a history of clinical stroke. Anticoagulation use and efficacy impact long-term risk of dementia in AF patients in observational trials. Methods: The Cognitive Decline and Dementia in Patients with Non-Valvular Atrial Fibrillation (CAF) Trial was a randomized, prospective, open-label vanguard clinical study with blinded endpoint assessment involving patients with moderate- to high-risk (CHADS2 or CHA2DS2-Vasc scores of ≥2) non-valvular AF assigned to dabigatran etexilate or warfarin. The primary endpoint was incident dementia or moderate cognitive decline at 24 months. Results: A total of 101 patients were enrolled, of which 50 received dabigatran and 51 warfarin anticoagulation. The mean age was 73.7±6.0 years and 54(53.5%) were male. Prior stroke and stroke risk factors were similar between groups. Average INR over the study was 2.41±0.68 in the warfarin group. No patient experienced a stroke or developed dementia. Mini-Mental Status Evaluation, Hachinski Ischemic scale, cognitive subscale of the Alzheimer’s Disease Assessment Scale, Disability Assessment for Dementia, Quality of Life Improvement as assessed by Minnesota Living with Heart Failure Scale and the Anti-Clot Treatment Scale Quality of Life Survey scores did not vary at baseline or change over 2 years. Biomarker analysis indicated a similar efficacy of anticoagulation strategies Conclusion: Use of dabigatran and well-managed warfarin therapy were associated with similar risks of stroke, cognitive decline, and dementia at 2 years, suggestive that either strategy is acceptable to mitigate these risks. The results of this Vanguard study did not support the pursuit of a larger formally powered study.
A 3D View of Orion: I. Barnard’s Loop
Michael Foley
Catherine Zucker

Michael Foley

and 12 more

March 07, 2023
Barnard’s Loop is a famous arc of H\(\alpha\) emission located in the Orion star-forming region. Here, we provide evidence of a possible formation mechanism for Barnard’s Loop and compare our results with recent work suggesting a major feedback event occurred in the region around 6 Myr ago. We present a 3D model of the large-scale Orion region, indicating coherent, radial, 3D expansion of the OBP-Near/Briceño-1 (OBP-B1) cluster in the middle of a large dust cavity. The large-scale gas in the region also appears to be expanding from a central point, originally proposed to be Orion X. OBP-B1 appears to serve as another possible center, and we evaluate whether Orion X or OBP-B1 is more likely to be the cause of the expansion. Recent 3D dust maps are used to characterize the 3D topology of the entire region, which shows Barnard’s Loop’s correspondence with a large dust cavity around the OPB-B1 cluster. The molecular clouds Orion A, Orion B, and Orion \(\lambda\) reside on the shell of this cavity. Simple estimates of gravitational effects from both stars and gas indicate that the expansion of this asymmetric cavity likely induced anisotropy in the kinematics of OBP-B1. We conclude that feedback from OBP-B1 has affected the structure of the Orion A, Orion B, and Orion \(\lambda\) molecular clouds and may have played a major role in the formation of Barnard’s Loop.
Experimental investigation of the effect of droplet size on the separation performanc...
Kul  Pun
F A Hamad

Kul Pun

and 6 more

June 14, 2022
This paper investigates the effect of liquid flow and oil pad thickness on the droplet size and separation performance. The findings show that increasing the inlet flow rates of the oil and water results in size reduction of the droplets. Increasing the thickness of the oil pad increases the size of the droplets. The measured data were fitted with a simple Gaussian model, and the fitted parameters of mean, standard deviation and amplitude were determined for each data set. Trends have been obtained from the fitted parameters as a function of the Reynolds number. The key parameter to predict and fix the position of the Gaussian distribution was found to be the mean droplet size. Simple Ab initio calculation methods to estimate this parameter was tested against the experimental data to identify the most promising method to predict this parameter for modelling purposes.
Effect of vapor transport on soil evaporation under different soil textures and water...
Xiuqiang Liu
Xi Chen

Xiuqiang Liu

and 4 more

June 14, 2022
In arid area, the liquid water and water vapor states in soil profiles and fluxes at the upper and bottom interfaces are extremely complex due to heterogeneity of soil textures and the driving forces of heat and matrix potential. In this study, we used Hydrus-1D to simultaneously simulate liquid water, water vapor, and heat transports based on the observed data of atmosphere, soil and groundwater at three soil profiles in an arid area of northwest China. Comparison and contrast of the observed and simulated results at the three soil profiles show that there are diurnal vapor entry and outlet fluxes at the dry surface layer (DSL) of 30 cm in the summer season. The vapor entry and re-evaporation account for about 14% of annual precipitation for the heterogeneity soil profile with a mean groundwater depth of 210 cm. Because of limited soil moisture in this arid area, vapor induced re-evaporation occurs shortly in the early daytime. Moreover, the extent of vapor entry, condensation and re-evaporation strong depends on soil properties and water table depths. The lower water table produces the drier soil surface, allowing more vapor entry, condensation and re-evaporation. Whereas the finer grained soil layers benefits the vapor fixation to produce zero fluxes that substantially inhibit the upward liquid water and vapor fluxes, and thereby reduces soil evaporation. The reduced soil evaporation correspondingly decreases the capillary effect on phreatic evaporation, proven by that soil evaporation decreases slowly with decline of water table and the large extinct depth of phreatic evaporation for the finer grained soil profiles. The estimated extinct depth is 180 cm and 200 cm for the soil profiles consisting of silt loam and loamy sand, respectively, much larger than 100 cm of the sandy soil profile. Additionally, as water table is higher and lower than the extinct depth, the models neglecting the vapor - heat function could respectively overestimate and underestimate soil evaporation.
Discharge and Floods Projected to Increase More Than Precipitation Extremes
Felipe Quintero Duque
Gabriele Villarini

Felipe Quintero Duque

and 4 more

June 14, 2022
Floods claim a high toll in fatalities and economic impacts. Despite their societal relevance, there is much more to learn about the projected changes in discharge and flooding. Here we force an operational hydrologic model over the state of Iowa with high-resolution convection-permitting climate-model precipitation to evaluate the response of 140 watersheds to climate change. At the end of the century, under the most aggressive scenario in terms of fossil fuel use, we show that the transition from snow to rainfall and a ~30% increase in extreme precipitation rates lead to a doubling of maximum discharge during the spring and extended the flood season into the fall. Total discharge volumes are also expected to increase. Our results suggest that flood projections based on extreme precipitation increases alone substantially underestimate future risk due to the nonlinearity of the hydrologic response explained by long-term soil moisture memory and its feedbacks with precipitation.
Impacts of climate change and human activities on streamflow of Upper Yongding River...
liqiang deng
Ying Guo

qiangli deng

and 4 more

June 14, 2022
Streamflow plays a key role in ecosystem and human society, which make it important to analyse the characteristics and influencing factors of streamflow. Using hydro-meteorological data series during 1961-2017 in the Upper Yongding River Basin (UYRB)( including Yang River Basin (YRB) and Sanggan River Basin (SRB)), Spatio-temporal variation characteristics of air temperature, precipitation and potential evapotranspiration (E 0) were analysed. Results showed that: precipitation has no significant trend; temperature shows a significant increase by 0.09–0.52℃ per decade; E 0 shows a significant decrease from -0.18 mm/yr to -2.04 mm/yr (in 18 stations); the estimated rates of streamflow change are –0.74, –0.80mm/yr for SRB and YRB. As to spatial distribution: the YRB presents a higher E 0 value than the SRB; and the mountain area has more precipitation than the plain area. And the change points of streamflow occurred in 1982 and 2003. Both Budyko and DMC method were used to evaluate the impacts of climate change and human activities on mean annual streamflow. In the variation stage Ⅰ (1983~2003), impacts of human activities account for 90.6% and 62.7% of the mean annual streamflow changes in YRB and SRB, respectively. In the variation stage Ⅱ (2004~2017), the percentages are 99.5% and 93.5%, respectively. It is also noted that the first change point in streamflow was indeed at the beginning of China’s land reform, when the farmers can manage their reallocated lands and therefore increased agricultural water consumption. The second change point coincided with “Capital Water Resources Planning” including water conservation projects and irrigation district construction programs. In general, human activities were mainly responsible for the significant decline in the annual streamflow of UYRB. This paper will provide valuable results for water resources planning and give guidance to the construction of water conservation function area and ecological environment support area of capital.
Editorial to the special issue “Environmental influences on childhood asthma”
S. Tolga Yavuz
Ömer  Kalaycı

S. Tolga Yavuz

and 2 more

June 14, 2022
Editorial to the special issue “Environmental influences on childhood asthma”Back in 1892, Sir William Osler gave an accurate description of asthma as a disease that is associated with “spasm of the bronchial muscles, inflammation of the smaller bronchioles, bizarre and extraordinary variety of circumstances and cold infections, often running in families (1,2). This is basically a true reflection of our modern understanding of asthma which states that asthma is a complex genetic disorder that involves interactions between genetic and environmental factors.Since the human genetic makeup has not changed significantly in the last couple of decades, there is reason to believe that the overall increase in asthma prevalence (3) can be attributed to the changing environmental conditions of modern life. The role of environment in asthma is not limited to its role in the pathogenesis of the disease. Since it is currently not possible to change the genetic make-up of an individual underlying a complex genetic disorder such as asthma, modification of environmental conditions emerges as a significant tool for its treatment. Therefore, understanding the environmental factors that play an important role in asthma is crucial in understanding the disease pathogenesis as well as modification of factors that modulate the inception and progress of the disease as well as its treatment.Various studies published in the last years in the journal and included in this virtual issue have addressed these questions. Garcia-Serna et al. have found out that gestational exposure to traffic-related air pollutants (TRAP) may increase the pro-inflammatory and Th2-related cytokines in newborns which might influence immune system responses later in life (4). Similarly, Pesce et al. (5) have investigated the association between prenatal exposures to heavy metals and atopic diseases. The serum concentrations of lead, cadmium and manganese were assessed in maternal blood samples collected during pregnancy and in cord blood of 651 mother-children pairs. The authors have concluded that the levels of cadmium in cord blood were associated with greater risk of asthma at the age of 8. Baek et al. have documented that exposure to phthalates are associated with airway dysfunction in childhood and this effect was partially attributable to increased serum periostin levels (6). Regarding the association between the genes and environment, Theodorou et al. (7) have investigated the role of mitogen-activated protein kinase (MAPK) pathway in 232 children who were selected from two cross-sectional cohorts and one birth cohort study. They have isolated peripheral blood mononuclear cells (PBMC) from children with asthma along with healthy controls and stimulated them with farm-dust extracts or lipopolysaccharide. The results have shown that the children with asthma have expressed significantly less dual-specificity phosphatase-1 (DUSP1) which is the negative regulator of MAPK pathway. They have conclusively indicated the possible role of DUSP1 for future therapeutical interventions regarding the anti-inflammatory features of farming environments.In an effort to further elucidate the environmental factors that are central to our understanding of asthma, the journal has started a review series to provide a comprehensive picture on the role of environment on various aspect of asthma. Major subheadings includedBiodiversityUrban exposuresGene-environment interactionsFarm effectAir pollutionClimate changeAllergensDiet microbiome and obesityIn the virtual issue of the journal Tari Haahtela (8) has focused on the effect of biodiversity. Evidence supports that the immunomodulating roles of different micro-organisms may be protective for asthma and allergic diseases. The studies from the neighboring Finnish and Russian Karelia regions, which the author named as “the living laboratory”, have shown strong evidence for the central role of environment and lifestyle which modify the human microbiome, immune balance, and thus allergy and asthma risk. Diversity of the human microbiome as well as the diversity of the natural environment that we live in and more contact with the nature are important determinants of physical health.Grant et al. (9) have focused on the influence of urban exposures on childhood asthma. The authors have meticulously summarized and analyzed the results of previous studies which aimed to investigate the interaction between indoor allergens, microbes, indoor and outdoor pollutants, social determinants and childhood asthma along with the opportunities for intervention. Multiple environmental exposures and influences contribute to the increased incidence of asthma and excess asthma morbidity among children with asthma living in urban communities. Indoor pest allergen and mold exposures have been repeatedly linked to increased asthma diagnosis, symptoms, and exacerbations in urban children. However, studies in high-risk urban populations also found that early life pest allergen exposure, along with microbial and endotoxin exposure may be associated with a decreased risk of wheezing and asthma suggesting that the association is more complex than previously thought.Since asthma prevalence varies widely depending on the socio-economical level, changes to help reduce inequities and inequalities in social determinants of health such as poverty, housing disrepair, higher rates of obesity, and chronic stress may produce positive effects at the population-level.Hernandez-Pacheco et al (10) have reviewed the latest gene-environment interaction (GxE) studies in childhood asthma. They have summarized the role of various environmental exposures and the current state of knowledge on asthma genetics. The field of GxE in asthma has drastically evolved together with technological advances over the last years. However, despite reports on the effect of numerous environmental factors on childhood asthma, the availability of detailed and diverse exposure data is limited. Tobacco smoke remains to be the most accessible and extensively explored factor followed by traffic-related air pollution in GxE studies.Airway epithelium seems to be central in gene-environment interactions. The effect of the exposure to certain environmental factors early in life on the modification of the risk and severity of asthma later in childhood is partially dependent on the functionality and integrity of the airway epithelium. It is known that the environmental exposures can trigger an inflammatory response and the disruption of the barrier and mucociliary function.Although there are several methodological and conceptual challenges with GxE interaction studies, recent data have led to new insights into childhood asthma pathophysiology which is best exemplified by the 17q12-21 asthma locus. Some of the SNPs at this locus seem to be associated with the onset of childhood asthma, thereby highlighting the importance of age related factors in gene environment interactions.The need for longitudinal and functional studies which provide insights into the biological mechanisms underlying the observed associations between environmental exposures and epigenetic changes that modify the asthma risk is highlighted.Another extensively studied environmental factor that is associated with childhood as is the so called “farm effect”. Frei et al. (11) have summarized the current knowledge on how “farm effect” influences the immune homeostasis during the intrauterine period and in childhood with a focus on immune mechanisms induced by environmental microbial diversity and microbial components. Farming lifestyle factors including nutrition influence the immune homeostasis either by regulating the innate immune system or by induction of regulatory T cells or TH1. We see diversity as a significant factor also in the farm effect. Diversity of environmental microbes, the diversity of the gut microbiome, or the diversity of the nutrition emerge as significant factors.Paciencia et al. (12) investigated the association and mechanisms between air pollution and asthma in children along with the precautions that should be taken to reduce the burden of air pollution on asthma. Environmental conditions are not shared equally across the populations, regions, and settings where people live, work, and spend their time. Urban conditions and air quality are not only important features for national and local authorities to shape healthy cities and protect their citizens from environmental and health risks, but they also provide opportunities to mitigate inequalities in the most deprived areas where the environmental burden is highest. Actions to avoid exposure to indoor and outdoor air pollutants should be complementary at different levels –individual, local, and national levels – to take strong measures to protect children.Taken together, these reviews provide a very comprehensive coverage on the role of environmental factors on childhood asthma and suggest that efforts to modify these factors may have beneficial effects not only on the individual level but also at the population level.S. Tolga Yavuz1Ömer Kalayci2Philippe A. Eigenmann3
Sudden-onset gallbladder rupture due to Ceftriaxone-associated pseudolithiasis in a p...
Naonori Harada
 Ikumi  Shibano

Naonori Harada

and 8 more

June 14, 2022
We herein report a 76-year-old man with acquired hemophilia A (AHA) who developed gallbladder rupture due to Ceftriaxone (CTRX)-associated pseudolithiasis. The patient was admitted for an examination of systemic subcutaneous bleeding. A blood test showed a prolonged activated partial thromboplastin time and sequentially revealed low factor VIII activity (<1%) and a high factor VIII inhibitor level of 143 BU/mL. The patient was thus diagnosed with AHA. After admission, he developed a high-grade fever and was administered intravenous CTRX, considering the possibility of psoas abscess or cellulitis. Although his high-grade fever was improved, computed tomography incidentally showed a high-density lesion in the gallbladder, suggestive of CTRX-associated pseudolithiasis without clinical symptoms. Despite cessation of CTRX, the pseudolithiasis never disappeared, and the patient suddenly died after rapid progression of abdominal bloating. An autopsy revealed that the gallbladder was severely swollen and had ruptured with hemorrhaging because of hemorrhagic cholecystitis, caused by CTRX-associated pseudolithiasis with AHA. Our case demonstrated that CTRX-associated pseudocholelithiasis can unexpectedly induce gallbladder hemorrhaging and rupture in a patient with a bleeding diathesis, including AHA. CTRX-associated pseudocholelithiasis can cause a fatal outcome in patients with a bleeding disorder, even if CTRX is ceased as soon as pseudocholelithiasis is detected.
LES investigation of flame acceleration and DDT of methane-air mixture in rectangular...
yongyao zhao
yanmin zhang

yongyao zhao

and 1 more

June 14, 2022
Large eddy simulation (LES) is used to simulate flame acceleration (FA) and deflagration to detonation transition (DDT) of methane–air mixtures in a small-scale 3D channel. The simulation results show that, in the early stages, the flame velocity increases exponentially because of the expansion of combustion products and the wrinkle of flame surface. In the next stage, the interaction between flame and pressure wave makes flame accelerate continuously, and the acceleration rate of the flame velocity decreases first and then increases. As the pressure of the leading shock increases, the boundary layer is heated by the preheating area in front of the flame surface which causes the ultrafast flame propagates in the boundary layer. The ultrafast flame generates oblique shock waves continuously moving to the center of the channel and colliding with each other, which promote the occurrence of local explosion and the coupling of flame surface and leading shock wave.
Asymptomatic course of overt primary hypothyroidism with a very high peak systolic ve...
Andrey Ushakov

Andrey Ushakov

June 14, 2022
This case a 59-year-old woman with asymptomatic overt hypothyroidism who presented with the Doppler ultrasound signs of increased thyroid exertion involving the autonomic nervous system. The findings suggest an increase in the rate of thyroxine deiodination and sufficiency of free triiodothyronine for the functional needs of the body.
Fatal invasive gastric mucormycosis: 2 case reports
amal khsiba
manel moalla

amal khsiba

and 6 more

June 14, 2022
Mucormycosis affects most commonly immunocompromised patients. We report two cases: a 61-year old female with diabetes whose the upper gastrointestinal endoscopy showed a budding greyish process which corresponded with an invasive mycormucosis in histology and a 59-year old man who presented with worsening of general state. No patients survived.
A right lower central incisor with a sinus tract at the labial gingiva that required...
Takayoshi Nagahara
Katsuhiro Takeda

Takayoshi Nagahara

and 4 more

June 14, 2022
Cone-beam computed tomography and clinical examinations including pulp vital testing and pocket probing depth showed a cemental tear with a severe labial alveolar bony defect, but no endodontic lesions in #25, which had a sinus tract at the labial site, in a 75-year-old woman.
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