Controllable Synthesis of Porous and Hollow Nanostructured Catalyst Particles and Their Soot Oxidation.

The introduction of macroporous structures into three-way catalysts (TWCs) through polymer template-assisted spray drying has attracted attention because of its enhanced gas diffusion and catalytic performance. However, the surface charge effect of polymeric template components has not been investigated to control the structure of the TWC particles during synthesis. Thus, this study investigated the effect of template surface charges on the self-assembly behavior of TWC nanoparticles (NPs) during drying. The self-assembly of TWC NPs and polymer particles with different charges produced a hollow structure, whereas using the same charges generated a porous one. Consequently, the mechanism of particle self-assembly during drying and final structure particle formation is proposed in this study. Here, porous TWC particles demonstrated a faster oxidation of soot particles than that of hollow-structured particles. This occurred as a result of the larger contact area between the catalyst surface and the solid reactant. Our findings propose a fundamental self-assembly mechanism for the formation of different TWC structures, thereby enhancing soot oxidation performance using macroporous structures.

Wait and watch: A trachoma surveillance strategy from Amhara region, Ethiopia.

BACKGROUND: Trachoma recrudescence after elimination as a public health problem has been reached is a concern for control programs globally. Programs typically conduct district-level trachoma surveillance surveys (TSS) ≥ 2 years after the elimination threshold is achieved to determine whether the prevalence of trachomatous inflammation-follicular (TF) among children ages 1 to 9 years remains <5%. Many TSS are resulting in a TF prevalence ≥5%. Once a district returns to TF ≥5%, a program typically restarts costly mass drug administration (MDA) campaigns and surveys at least twice, for impact and another TSS. In Amhara, Ethiopia, most TSS which result in a TF ≥5% have a prevalence close to 5%, making it difficult to determine whether the result is due to true recrudescence or to statistical variability. This study's aim was to monitor recrudescence within Amhara by waiting to restart MDA within 2 districts with a TF prevalence ≥5% at TSS, Metema = 5.2% and Woreta Town = 5.1%. The districts were resurveyed 1 year later using traditional and alternative indicators, such as measures of infection and serology, a "wait and watch" approach. METHODS/PRINCIPAL FINDINGS: These post-surveillance surveys, conducted in 2021, were multi-stage cluster surveys whereby certified graders assessed trachoma signs. Children ages 1 to 9 years provided a dried blood spot and children ages 1 to 5 years provided a conjunctival swab. TF prevalence in Metema and Woreta Town were 3.6% (95% Confidence Interval [CI]:1.4-6.4) and 2.5% (95% CI:0.8-4.5) respectively. Infection prevalence was 1.2% in Woreta Town and 0% in Metema. Seroconversion rates to Pgp3 in Metema and Woreta Town were 0.4 (95% CI:0.2-0.7) seroconversions per 100 child-years and 0.9 (95% CI:0.6-1.5) respectively. CONCLUSIONS/SIGNIFICANCE: Both study districts had a TF prevalence <5% with low levels of Chlamydia trachomatis infection and transmission, and thus MDA interventions are no longer warranted. The wait and watch approach represents a surveillance strategy which could lead to fewer MDA campaigns and surveys and thus cost savings with reduced antibiotic usage.

Exopolysaccharide-Treated Dendritic Cells Effectively Ameliorate Acute Graft-versus-Host Disease.

Graft-versus-host disease (GVHD) is a primary and often lethal complication of allogenic hematopoietic stem cell transplantation (HSCT). Prophylactic regimens for GVHD are given as standard pretransplantation therapy; however, up to 50% of these patients develop acute GVHD (aGVHD) and require additional immunosuppressive intervention. Using a mouse GVHD model, we previously showed that injecting mice with exopolysaccharide (EPS) from Bacillus subtilis prior to GVHD induction significantly increased 80-day survival after transplantation of complete allogeneic major histocompatibility complex-mismatched cells. To ask whether EPS might also inhibit GVHD in humans, we used humanized NSG-HLA-A2 mice and induced GVHD by i.v. injection of A2neg human peripheral blood mononuclear cells (PBMCs). Because we could not inject human donors with EPS, we transferred EPS-pretreated dendritic cells (DCs) to inhibit aGVHD. We derived these DCs from CD34+ human cord blood cells, treated them with EPS, and then injected them together with PBMCs into the NSG-HLA-A2 mice. We found that all mice that received untreated DCs were dead by day 35, whereas 25% of mice receiving EPS-treated DCs (EPS-DCs) survived. This DC cell therapy could be readily translatable to humans, because we can generate large numbers of human EPS-DCs and use them as an "off the shelf" treatment for patients undergoing HSCT.

NKG2D receptor signaling shapes T cell thymic education.

The role of natural killer group 2D (NKG2D) in peripheral T cells as a costimulatory receptor is well established. However, its contribution to T cell thymic education and functional imprint is unknown. Here, we report significant changes in development, receptor signaling, transcriptional program, and function in T cells from mice lacking NKG2D signaling. In C57BL/6 (B6) and OT-I mice, we found that NKG2D deficiency results in Vß chain usage changes and stagnation of the double-positive stage in thymic T cell development. We found that the expression of CD5 and CD45 in thymocytes from NKG2D deficient mice were reduced, indicating a direct influence of NKG2D on the strength of T cell receptor (TCR) signaling during the developmental stage of T cells. Depicting the functional consequences of NKG2D, peripheral OT-I NKG2D-deficient cells were unresponsive to ovalbumin peptide stimulation. Paradoxically, while αCD3/CD28 agonist antibodies led to phenotypic T cell activation, their ability to produce cytokines remained severely compromised. We found that OT-I NKG2D-deficient cells activate STAT5 in response to interleukin-15 but were unable to phosphorylate ERK or S6 upon TCR engagement, underpinning a defect in TCR signaling. Finally, we showed that NKG2D is expressed in mouse and human thymic T cells at the double-negative stage, suggesting an evolutionarily conserved function during T cell development. The data presented in this study indicate that NKG2D impacts thymic T cell development at a fundamental level by reducing the TCR threshold and affecting the functional imprint of the thymic progeny. In summary, understanding the impact of NKG2D on thymic T cell development and TCR signaling contributes to our knowledge of immune system regulation, immune dysregulation, and the design of immunotherapies.

DFT approach towards accurate prediction of 1H/13C NMR chemical shifts for dipterocarpol oxime.

A computational NMR approach for accurate predicting the 1H/13C chemical shifts of triterpenoid oximes featuring the screening of 144 DFT methods was demonstrated. Efficiently synthesized dipterocarpol oxime was employed as a model compound. The six highest accurate methods from the screening generated root-mean-square-error (RMSE) values in the range of 0.84 ppm (0.55%) to 1.14 ppm (0.75%) for calculated 13C shifts. For 1H results, simple, economical 6-31G basis set unexpectedly outperformed other more expensive basic sets; and the couple of it with selected functionals provided high accuracy shifts (0.0617 ppm (1.49%) ≤ RMSE ≤ 0.0870 ppm (2.04%)). These computational results strongly supported the proton and carbon assignments of the oxime including the difficult ones of diastereotopic methyl groups, the methyl groups attached to an internal olefin, and diastereotopic α-protons.

Macropore-Size Engineering toward Enhancing the Catalytic Performance of CO Oxidation over Three-Way Catalyst Particles.

In recent years, transportation-related air pollution has escalated into a global concern, necessitating the development of a three-way catalyst (TWC) technology to address harmful emissions. However, the efficiency of TWC's performance in mitigating these emissions has been hindered because of limited mass transfer efficiency within their structures. Thus, this study attempted to overcome the existing issue by synthesizing a series of macroporous TWC particles exhibiting various macropore sizes via a template-assisted spray process, aiming to achieve optimal mass transfer efficiency and catalytic performance. The synthesis incorporated various template particles (size of 67-381 nm) to obtain various macroporous structures. Thereafter, these macroporous particles were assessed for their carbon monoxide (CO) oxidation performance, revealing a substantial influence of the macropore size on the catalytic performance of TWC structures. Interestingly, among the investigated samples, those containing the smallest and largest macropores demonstrated the highest CO oxidation performances. Based on these results, a plausible reactant diffusion mechanism was proposed to explain the effect of the macropore size on the diffusion efficiency within the macroporous structures. This work may have significant implications in optimizing the macroporous structure to enhance catalytic performance in the gas purification process.

Bayesian merging of numerical modeling and remote sensing for saltwater intrusion quantification in the Vietnamese Mekong Delta.

Saltwater intrusion has become one of the most concerning issues in the Vietnamese Mekong Delta (VMD) due to its increasing impacts on agriculture and food security of Vietnam. Reliable estimation of salinity plays a crucial role to mitigate the impacts of saltwater intrusion. This study developed a hybrid technique that merges satellite imagery with numerical simulations to improve the estimation of salinity in the VMD. The salinity derived from Landsat images and by numerical simulations was fused using the Bayesian inference technique. The results indicate that our technique significantly reduces the uncertainties and improves the accuracy of salinity estimates. The Nash-Sutcliffe coefficient is 0.74, which is much higher than that of numerical simulation (0.63) and Landsat estimation (0.6). The correlation coefficient between the ensemble and measured salinity is relatively high (0.88). The variance of the ensemble salinity errors (5.0 ppt2) is lower than that of Landsat estimation (10.4 ppt2) and numerical simulations (9.6 ppt2). The proposed approach shows a great potential to combine multiple data sources of a variable of interest to improve its accuracy and reliability wherever these data are available.

Climate-driven changes in the predictability of seasonal precipitation.

Climate-driven changes in precipitation amounts and their seasonal variability are expected in many continental-scale regions during the remainder of the 21st century. However, much less is known about future changes in the predictability of seasonal precipitation, an important earth system property relevant for climate adaptation. Here, on the basis of CMIP6 models that capture the present-day teleconnections between seasonal precipitation and previous-season sea surface temperature (SST), we show that climate change is expected to alter the SST-precipitation relationships and thus our ability to predict seasonal precipitation by 2100. Specifically, in the tropics, seasonal precipitation predictability from SSTs is projected to increase throughout the year, except the northern Amazonia during boreal winter. Concurrently, in the extra-tropics predictability is likely to increase in central Asia during boreal spring and winter. The altered predictability, together with enhanced interannual variability of seasonal precipitation, poses new opportunities and challenges for regional water management.

Designing the Macroporous Structure of Three-Way Catalyst Particles: The Influence of Template Concentration on Framework Thickness and Mass Transfer.

Mass transfer is an essential process that can extend the performance and utilization of nanoporous materials in various applications. Therefore, improving mass transfer in nanoporous materials has always attracted much interest, and macroporous structures are currently being studied to enhance mass transfer performance. The introduction of macroporous structures into three-way catalysts (TWC), which are widely utilized to control the emission of polluted gases from vehicles, provides the potential to enhance their mass transfer property and catalytic performance. However, the formation mechanism of macroporous TWC particles has not yet been investigated. On the other hand, the influence of the framework thickness of the macroporous structure on the mass transfer enhancement is still unclear. Therefore, this report investigates the particle formation and framework thickness of the macroporous TWC particles synthesized using the template-assisted aerosol process. The formation of macroporous TWC particles was precisely controlled and investigated by altering the size and concentration of the template particles. The template concentration played a crucial role in maintaining the macroporous structure and controlling the framework thickness between the macropores. Based on these results, a theoretical calculation showing the influence of template concentration on the particle morphology and framework thickness was developed. The final results showed that increasing the template concentration can positively affect the nanoporous material's framework thickness reduction and mass transfer coefficient improvement.

Reduced Time to Surgery and Prophylactic Fasciotomy May Result in Improved Outcomes in Popliteal Artery Injuries.

BACKGROUND: Popliteal artery injuries are uncommon and often result in limb loss or long-term limb dysfunction. The aims of this study were (1) to evaluate the association between predictors and outcomes and (2) to validate the rational of systematic early fasciotomy. METHODS: This retrospective cohort study included 122 patients (80% men, n = 100) who underwent surgery for popliteal artery injuries from October 2018 to March 2021 in southern Vietnam. Primary outcomes included primary and secondary amputation. The associations between predictors and primary amputation were analyzed using logistic regression models. RESULTS: Among the 122 patients, 11 (9%) underwent primary amputation, while 2 (1.6%) had secondary amputation. Longer time to surgery was associated with increased odds of amputation (odds ratio = 1.65; 95% confidence interval, 1.2 to 2.2 for every 6 hr). Severe limb ischemia was also associated with a 50-fold increase in the risk of primary amputation (adjusted odds ratio = 49.9; 95% confidence interval, 6 to 418, P = 0.001). Furthermore, 11 patients (9%) without signs of severe limb ischemia and acute compartment syndrome on admission were found to have myonecrosis of at least one muscle compartment during fasciotomy. CONCLUSIONS: The data suggest that among patients with popliteal artery injuries, prolonged time before surgery and severe limb ischemia are associated with increased risk of primary amputation, whereas early fasciotomy may lead to improved outcomes.

Historical spatiotemporal changes in fire danger potential across biomes.

This study 1) identifies the seasons and biomes that exhibit significant (1980-2019) changes in fire danger potential, as quantified by the Canadian Fire Weather Index (FWI); 2) explores what types of fire behavior potentials may be contributing to changes in fire danger potential, as quantified by the United States Energy Release Component (ERC) and the Ignition Component (IC); 3) provides spatiotemporal insight on how fire danger potential and fire behavior potential are responding in relation to changes in seasonal precipitation totals and seasonal mean air temperature across biomes. Time series of these fire potentials, as well as seasonal mean temperature, and seasonal precipitation totals are generated using data from the 0.25° ECMWF spatial resolution Reanalysis 5th Generation (ERA5) and the Climatic Research Unit gridded Time Series (CRU TS). The Mann-Kendall test is then applied to identify significant spatiotemporal trends across each biome. Results indicate that the September-November season (SON) exhibits the greatest rate of increase in fire danger potential, followed by the June-August season (JJA), December, January-February season (DJF), and March-May season (MAM), and this is predominant over the Tropical and Subtropical Moist Broadleaf Forest Biome, as well as all vegetation types of the temperate biomes. Similarly, the temperate biomes experience the greatest rate of increase in fire intensity potential and ignition potential, but prevalent during the DJF and MAM seasons. Furthermore, there is a significant positive correlation between fire danger potential and seasonal mean air temperature during JJA in the Northern Hemisphere for the temperate biomes in North America and Europe, as well as the Tropical and Subtropical biomes in Africa. Our analysis provides quantitative insight as to how fire danger potential and fire behavior potential have been responding to changes in seasonal mean temperature and seasonal precipitation totals across different ecoregions around the world.

Optimising diagnosis and treatment of tuberculosis infection in community and primary care settings in two urban provinces of Viet Nam: a cohort study.

OBJECTIVES: To end tuberculosis (TB), the vast reservoir of 1.7-2.3 billion TB infections (TBIs) must be addressed, but achieving global TB preventive therapy (TPT) targets seems unlikely. This study assessed the feasibility of using interferon-γ release assays (IGRAs) at lower healthcare levels and the comparative performance of 3-month and 9-month daily TPT regimens (3HR/9H). DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: This cohort study was implemented in two provinces of Viet Nam from May 2019 to September 2020. Participants included household contacts (HHCs), vulnerable community members and healthcare workers (HCWs) recruited at community-based TB screening events or HHC investigations at primary care centres, who were followed up throughout TPT. PRIMARY AND SECONDARY OUTCOMES: We constructed TBI care cascades describing indeterminate and positivity rates to assess feasibility, and initiation and completion rates to assess performance. We fitted mixed-effects logistic and stratified Cox models to identify factors associated with IGRA positivity and loss to follow-up (LTFU). RESULTS: Among 5837 participants, the indeterminate rate was 0.8%, and 30.7% were IGRA positive. TPT initiation and completion rates were 63.3% (3HR=61.2% vs 9H=63.6%; p=0.147) and 80.6% (3HR=85.7% vs 9H=80.0%; p=0.522), respectively. Being male (adjusted OR=1.51; 95% CI: 1.28 to 1.78; p<0.001), aged 45-59 years (1.30; 1.05 to 1.60; p=0.018) and exhibiting TB-related abnormalities on X-ray (2.23; 1.38 to 3.61; p=0.001) were associated with positive IGRA results. Risk of IGRA positivity was lower in periurban districts (0.55; 0.36 to 0.85; p=0.007), aged <15 years (0.18; 0.13 to 0.26; p<0.001), aged 15-29 years (0.56; 0.42 to 0.75; p<0.001) and HCWs (0.34; 0.24 to 0.48; p<0.001). The 3HR regimen (adjusted HR=3.83; 1.49 to 9.84; p=0.005) and HCWs (1.38; 1.25 to 1.53; p<0.001) showed higher hazards of LTFU. CONCLUSION: Providing IGRAs at lower healthcare levels is feasible and along with shorter regimens may expand access and uptake towards meeting TPT targets, but scale-up may require complementary advocacy and education for beneficiaries and providers.

Typhoid Fever in the Eastern Mediterranean Region: A Systematic Review, 1990-2021.

The occurrence and antimicrobial resistance (AMR) of typhoid fever in the WHO Eastern Mediterranean Region (EMR) are poorly characterized. Robust surveillance data are needed to inform strategies for typhoid control and prevention in the region. We conducted a systematic review of typhoid fever occurrence, complications, and AMR patterns in EMR countries. We identified 70 studies published from 1990 to 2021, including a total of 44,541 cases with blood culture confirmed typhoid fever in 12 EMR countries, with 48 (69%) studies and 42,008 cases from Pakistan. Among 56 studies with AMR data, fluroquinolone (68% of 13,013 tested isolates), and multidrug resistance (40% of 15,765 tested isolates) were common. Forty (57%) of the 56 studies were from Pakistan, and all reports of extensively drug resistant Salmonella Typhi (48% of 9,578 tested isolates) were from studies in Pakistan. Our findings support the need for continued efforts to strengthen surveillance and laboratory capacity for blood-culture detection of typhoid fever in the region, including data from an ongoing collaboration among CDC, the American University of Beirut, and the WHO EMR office.

Social Memory in the Mekong's Changing Floodscapes: Narratives of Agrarian Communities' Adaptation.

Rural adaptation encompasses place-based perceptions, behaviors, livelihoods, and traditional ways of life associated with local environments. These perceptions, norms, and practices are disturbed by coupled environment-development externalities. This study employs the Vietnamese Mekong floodplains as an exemplary case to illustrate how floods impact agrarian communities and how they have experienced flood alterations driven by hydropower development and climate change in recent years. Drawing on thematic and narrative analyses of qualitative data (focus group discussions and interviews) collected in three agrarian communities in the Vietnamese Mekong floodplains, sources drawn from various news outlets, and academic materials, we argue that disrupted flood environments in the floodplains have triggered affective flood reminiscences, catalysing shifts to incremental and transformative adaptation to achieve resilience. We build a nuanced understanding of how social memory helps to enhance human-environment relationships in response to highly complex hydrological dynamics in the delta.

A Dynamic Visualization Tool of Local Trends in Heart Disease and Stroke Mortality in the United States.

Efforts in the US to prevent and treat cardiovascular disease (CVD) contributed to large decreases in death rates for decades; however, in the last decade, progress has stalled, and in many counties, CVD death rates have increased. Because of these increases, there is heightened urgency to disseminate high-quality data on the temporal trends in CVD mortality. The Local Trends in Heart Disease and Stroke Mortality Dashboard is an online, interactive visualization of US county-level death rates and trends for several CVD outcomes across stratifications of age, race and ethnicity, and sex. This powerful visualization tool generates national maps of death rates and trends, state maps of death rates and trends, county-level line plots of annual death rates, and bar charts of percentage changes. County-level death rates and trends were estimated by applying a Bayesian spatiotemporal model to data obtained from the National Vital Statistics System of the National Center for Health Statistics and US Census bridged-race intercensal estimates for the years 1999 through 2019. The Local Trends in Heart Disease and Stroke Mortality Dashboard makes it easy for public health practitioners, health care providers, and community leaders to monitor county-level spatiotemporal trends in CVD mortality by age group, race and ethnicity, and sex and provides key information for identifying and addressing local health inequities in CVD mortality trends.

A Sustainable Approach for Preparing Porous Carbon Spheres Derived from Kraft Lignin and Sodium Hydroxide as Highly Packed Thin Film Electrode Materials.

A green synthetic strategy to design biomass-derived porous carbon electrode materials with precisely tailored structure and morphology has always been a challenging goal because these materials can fulfill the demands of next-generation supercapacitors and other electrochemical devices. Potassium hydroxide (KOH) is extensively utilized as an activator since it can produce porous carbon with high specific surface area and well-developed porous channels. The exploitation of sodium hydroxide (NaOH) as an activating agent is less referenced in the literature, although it offers some advantages over KOH in terms of low cost, less corrosiveness, and simple handling procedure, all of which are appealing particularly from an industrial viewpoint. The motivation for this present study is to fabricate porous carbon spheres in a sustainable manner via a spray drying approach followed by a carbonization process, using Kraft lignin as the carbon precursor and NaOH as an alternative activation agent instead of the high-cost and high-corrosive KOH for the first time. The structure of carbon particles can be accurately transitioned from a compact to hollow structure, and the surface textural properties can be easily tuned by altering the NaOH concentration. The obtained porous carbon spheres were applied as highly packed thin film electrode materials for supercapacitor devices. The specific capacitance value of porous carbon spheres with a highly compact structure (high packing density) is 66.5 F g-1, which is higher than that of commercial activated carbon and other biomass-derived carbon. This work provides a green processing for producing low-cost and environment-friendly porous carbon spheres from abundant Kraft lignin and important insight for selecting NaOH as an activator to tailor the morphology and structure, which represents an economical and sustainable approach for energy storage devices.

Underestimated MJO variability in CMIP6 models.

The Madden-Julian Oscillation (MJO) is the leading mode of intra-seasonal climate variability, having profound impacts on a wide range of weather and climate phenomena. Here, we use a wavelet-based spectral Principal Component Analysis (wsPCA) to evaluate the skill of 20 state-of-the-art CMIP6 models in capturing the magnitude and dynamics of the MJO. By construction, wsPCA has the ability to focus on desired frequencies and capture each propagative physical mode with one principal component (PC). We show that the MJO contribution to the total intra-seasonal climate variability is substantially underestimated in most CMIP6 models. The joint distribution of the modulus and angular frequency of the wavelet PC series associated with MJO is used to rank models relatively to the observations through the Wasserstein distance. Using Hovmöller phase-longitude diagrams, we also show that precipitation variability associated with MJO is underestimated in most CMIP6 models for the Amazonia, Southwest Africa, and Maritime Continent.