High BD Research Articles

Apron surveillance video coding based on compositing virtual reference frame with object library

AbstractA video coding framework for the apron surveillance scene has been proposed in this paper, which aims to improve coding efficiency by eliminating long‐term redundancy at the object level. To achieve this goal, this study first develops an existing block‐based hybrid video coding framework by exploiting the video redundancy on the object level to perform video coding. Second, an object‐library mechanism is designed to collect the representative object images as coding references on larger temporal and spatial scales. Finally, a virtual reference frame, which blends background and foreground references from the object library, is adaptively composited according to the video content to improve the inter‐prediction performance. Preliminary experimental results demonstrate that the proposed method achieves a high BD rate reduction of up to 23.97% in apron surveillance video sequences, compared to the standard high efficiency video coding (HEVC).

Fast and efficient identification of hyaluronidase specific inhibitors from Chrysanthemum morifolium Ramat. using UF-LC-MS technique and their anti-inflammation effect in macrophages

The purpose of the study was to establish a rapid analytical strategy to screen potential anti-inflammatory compounds from Flos Chrysanthemum flower. The enzyme assay was conducted to prescreen botanical extracts, in which Chrysanthemum morifolium aqueous extract (CME) displayed hyaluronidase (HAase) inhibitory activity in a dose-dependent manner with the values of 8.31, 24.25, and 66.51% at concentrations of 1.00, 2.00, and 4 0.00 mg/mL, respectively. Eight potential compounds targeting HAase (compounds 9, 10, 11, 13, 15, 17, 20 and 21) from CME were screened using ultrafiltration affinity liquid chromatography coupled with mass spectrometry (UF-LC-MS) technology. The well-known inhibitor, dipotassium glycyrrhizinate (DG), was used as a positive control and competitive ligand to eliminate false positives. Then, four of these potential components (compounds 9, 10, 17, and 21), namely eriodictyol-7-O-glucoside, luteoloside, apigenin-7-O-glucoside and diosmetin-7-O-glucoside, were distinguished as potent HAase specific inhibitor candidates with high BD and CBD values. The enzyme inhibitory activities of candidate compounds were verified using enzyme inhibition assay. At a concentration of 1000 μM, compounds 9, 10, 17, and 21 showed 40.15, 44.85, 18.04, and 24.15% inhibition of HAase, respectively. Furthermore, all the four compounds significantly decreased the production of nitric oxide (NO) and IL-6, and significantly suppressed the mRNA expression of inducible NO synthase (iNOS) and IL-1β in both murine and human macrophages.

Immune priming prior to pathogen exposure sheds light on the relationship between host, microbiome and pathogen in disease.

Dynamic interactions between host, pathogen and host-associated microbiome dictate infection outcomes. Pathogens including Batrachochytrium dendrobatidis (Bd) threaten global biodiversity, but conservation efforts are hindered by limited understanding of amphibian host, Bd and microbiome interactions. We conducted a vaccination and infection experiment using Eastern hellbender salamanders (Cryptobranchus alleganiensis alleganiensis) challenged with Bd to observe infection, skin microbial communities and gene expression of host skin, pathogen and microbiome throughout the experiment. Most animals survived high Bd loads regardless of their vaccination status and vaccination did not affect pathogen load, but host gene expression differed based on vaccination. Oral vaccination (exposure to killed Bd) stimulated immune gene upregulation while topically and sham-vaccinated animals did not significantly upregulate immune genes. In early infection, topically vaccinated animals upregulated immune genes but orally and sham-vaccinated animals downregulated immune genes. Bd increased pathogenicity-associated gene expression in late infection when Bd loads were highest. The microbiome was altered by Bd, but there was no correlation between anti-Bd microbe abundance or richness and pathogen burden. Our observations suggest that hellbenders initially generate a vigorous immune response to Bd, which is ineffective at controlling disease and is subsequently modulated. Interactions with antifungal skin microbiota did not influence disease progression.

The skin microbiota of the axolotl Ambystoma altamirani is highly influenced by metamorphosis and seasonality but not by pathogen infection

BackgroundMicrobiomes have been increasingly recognized as major contributors to host health and survival. In amphibians, bacterial members of the skin microbiota protect their hosts by inhibiting the growth of the fungal pathogen Batrachochytrium dendrobatidis (Bd). Even though several studies describe the influence of biotic and abiotic factors over the skin microbiota, it remains unclear how these symbiotic bacterial communities vary across time and development. This is particularly relevant for species that undergo metamorphosis as it has been shown that host physiology and ecology drastically influence diversity of the skin microbiome.ResultsWe found that the skin bacterial communities of the axolotl A. altamirani are largely influenced by the metamorphic status of the host and by seasonal variation of abiotic factors such as temperature, pH, dissolved oxygen and conductivity. Despite high Bd prevalence in these samples, the bacterial diversity of the skin microbiota did not differ between infected and non-infected axolotls, although relative abundance of particular bacteria were correlated with Bd infection intensity.ConclusionsOur work shows that metamorphosis is a crucial process that shapes skin bacterial communities and that axolotls under different developmental stages respond differently to environmental seasonal variations. Moreover, this study greatly contributes to a better understanding of the factors that shape amphibian skin microbiota, especially in a largely underexplored group like axolotls (Mexican Ambystoma species).

Recovered frog populations coexist with endemic Batrachochytrium dendrobatidis despite load-dependent mortality.

Novel infectious diseases, particularly those caused by fungal pathogens, pose considerable risks to global biodiversity. The amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) has demonstrated the scale of the threat, having caused the greatest recorded loss of vertebrate biodiversity attributable to a pathogen. Despite catastrophic declines on several continents, many affected species have experienced population recoveries after epidemics. However, the potential ongoing threat of endemic Bd in these recovered or recovering populations is still poorly understood. We investigated the threat of endemic Bd to frog populations that recovered after initial precipitous declines, focusing on the endangered rainforest frog Mixophyes fleayi. We conducted extensive field surveys over 4 years at three independent sites in eastern Australia. First, we compared Bd infection prevalence and infection intensities within frog communities to reveal species-specific infection patterns. Then, we analyzed mark-recapture data of M. fleayi to estimate the impact of Bd infection intensity on apparent mortality rates and Bd infection dynamics. We found that M. fleayi had lower infection intensities than sympatric frogs across the three sites, and cleared infections at higher rates than they gained infections throughout the study period. By incorporating time-varying individual infection intensities, we show that healthy M. fleayi populations persist despite increased apparent mortality associated with infrequent high Bd loads. Infection dynamics were influenced by environmental conditions, with Bd prevalence, infection intensity, and rates of gaining infection associated with lower temperatures and increased rainfall. However, mortality remained constant year-round despite these fluctuations in Bd infections, suggesting major mortality events did not occur over the study period. Together, our results demonstrate that while Bd is still a potential threat to recovered populations of M. fleayi, high rates of clearing infections and generally low average infection loads likely minimize mortality caused by Bd. Our results are consistent with pathogen resistance contributing to the coexistence of M. fleayi with endemic Bd. We emphasize the importance of incorporating infection intensity into disease models rather than infection status alone. Similar population and infection dynamics likely exist within other recovered amphibian-Bd systems around the globe, promising longer-term persistence in the face of endemic chytridiomycosis.

Assessment of Physical Suitability of Soils for Vegetable Production in the Libga Irrigation Scheme, Northern Region, Ghana Using the Analytic Hierarchy Process and Weighted Overlay Analysis

Assessing the suitability of soils for agricultural production is critical in promoting sustainable agriculture. Knowledge gained from soil suitability analysis provides the sound basis for making informed decisions about soil management and crop selection in a given area. In view of this, this study was carried out to assess the physical suitability of soils in the Libga Irrigation Scheme for the sustainable cultivation of jute mallow (Corchorus olitorius), tomato (Solanum lycoperscum L.) and cabbage (Brassica oleracea var capitata). Soil samples were collected at 0–30 cm and 30–60 cm depths from 50 geo-referenced points located at the nodes of a 100 m × 100 m regular grid. Particle size distribution, bulk density, total porosity, field capacity, permanent wilting point, available water capacity, saturated hydraulic conductivity, electrical conductivity and pH were determined following standard laboratory protocols at the AGSSIP Laboratory of the University for Development Studies, Nyankpala campus, Ghana. Weighting of soil properties was achieved through the analytic hierarchy process (AHP). Soil suitability maps for the selected crops were produced using weighted overlay analysis in ArcGIS (10.5). The results showed that generally about 44.3 ha (76.4 %), 44.7 ha (82.2 %) and 55.7 ha (96.0 %) of the irrigation field are moderately suitable for jute mallow, tomato and cabbage production respectively. The major limiting factors for the crops were high BD and acidity levels. The AHP proved to be a very useful tool for the incorporation of farmers’ views into decision making about the suitability of soils for crop production.

Design, synthesis and biological evaluation of (Quinazoline 4-yloxy)acetamide and (4-oxoquinazoline-3(4H)-yl)acetamide derivatives as inhibitors of Mycobacterium tuberculosis bd oxidase

New chemical scaffolds with novel mechanism of action are urgently needed for the treatment of drug resistant tuberculosis. The oxidative phosphorylation pathway of Mycobacterium tuberculosis consists of multiple clinically validated drug targets. This pathway can function through any one of the two terminal oxidases-the proton pumping cytochrome bc1-aa3 supercomplex, or the less energy efficient but high affinity cytochrome bd oxidase. Inhibiting the bc1 complex alone has been found bacteriostatic and not bactericidal. On the other hand, inhibition of both these oxidases turns lethal to the pathogen. In the present study, we used a bc1 complex mutant of M. tuberculosis to screen (Quinazoline 4-yloxy)acetamide and (4-oxoquinazoline-3(4H)-yl)acetamide derivatives against the alternate oxidase, i.e., cytochrome bd oxidase. Two molecules, S-021-0601 and S-021-0607 were found to inhibit the mutant with MICs 8 and 16 μM respectively, compared to MICs of 128 and 256 μM against the wild type M. tuberculosis. In the wild type, one of the compounds showed synergism with Q203, an inhibitor of bc1 complex, in inhibiting growth under aerobic conditions. Both compounds showed synergism with Q203 in depleting bacterial ATP and inhibiting oxygen consumption. Both the compounds at 32 μM (one-fourth or one-eighth of their MICs for wild type) were bactericidal to wild type bacteria under hypoxic condition, causing ∼1.9 log10 reduction in viable counts which increased to ∼4-log10 when combined with Q203.

Efficient Production of 1,3-Butadiene from 1,4-Butanediol over Yb2O3 Catalyst Prepared through Hydrothermal Aging

Abstract Vapor-phase catalytic dehydration of 1,4-butanediol (1,4-BDO) was investigated over rare earth metal oxide (RE2O3) catalysts to produce 1,3-butadiene (BD). Among eight RE2O3, Yb2O3 showed the highest catalytic activity to produce BD via an intermediate 3-buten-1-ol (3B1OL). Hydrothermal (HT) aging of precursor precipitate of Yb2O3 greatly enhanced the catalytic activity and the selectivity to 3B1OL of the resulting Yb2O3 catalyst. It was confirmed that the morphology of Yb2O3 and the catalytic activity varied with the HT conditions. Hydrothermally aged Yb2O3 reduced the formation of propylene, a decomposed product of 3B1OL, even at high temperatures above 400 °C. HT-aged Yb2O3 followed by calcination at 700 °C showed excellent catalytic activity in the dehydration of 1,4-BDO with the highest BD productivity of 34.6 mol kgcat−1 h−1 and a high BD yield of 97.4% at 450 °C.

High fungal pathogen loads and prevalence in Baja California amphibian communities: The importance of species, elevation, and historical context

Amphibians are declining globally, and the fungal pathogen Batrachochytrium dendrobatidis (Bd), which causes the disease chytridiomycosis, has been the culprit in many of these declines. In the Mediterranean region of Baja California, Mexico—a biodiversity hotspot—native amphibians are also in decline, and Bd is present. To determine which factors best predict Bd infection prevalence and intensity in Baja California anurans, we conducted Bd sampling at three disparate sites at varying elevations. We observed an overall Bd prevalence of 68%, and found that species was an important predictor of pathogen prevalence and burden (load) both across and within sites. Pathogen prevalence and load increased positively with elevation. The highest Bd load we detected was 139,188 zoospore equivalents (ZE) in a western toad ( Anaxyrus boreas )—more than 10 times the pathogen burden at which chytridiomycosis is lethal in some species. We observed high Bd prevalence (84 – 99%) and Bd loads (> 44,000 ZE) in the California red-legged frog ( Rana draytonii )—a cause for concern in this threatened anuran, especially at La Grulla—the highest elevation (2050 m) site for this species across its range. We sampled museum specimens to determine how long Bd has been present in the region, and detected the pathogen as early as 1932. Contemporary Bd prevalence and load in Baja California are considerably higher than would be expected given similar habitats and the same community composition as in southern California, USA. We therefore highlight the importance of historical context and comparative analyses in examining contemporary Bd dynamics, as well as adhering to strict biosecurity measures when implementing reintroductions and translocations.

Interpopulation differences in male reproductive effort drive the population dynamics of a host exposed to an emerging fungal pathogen.

Compensatory recruitment is a key demographic mechanism that has allowed the coexistence of populations of susceptible amphibians with Batrachochytrium dendrobatidis (Bd), a fungus causing one of the most devastating emerging infectious disease ever recorded among vertebrates. However, the underlying processes (e.g. density-dependent increase in survival at early life stages, change in reproductive traits) as well as the level of interpopulation variation in this response are poorly known. We explore potential mechanisms of compensatory recruitment in response to Bd infection by taking advantage of an amphibian system where male reproductive traits are easy to quantify in free-living populations. The Southern Darwin's frog Rhinoderma darwinii is a vocal sac-brooding species that exhibits a high susceptibility to lethal Bd infection. Using a 7-year capture-recapture study at four populations with contrasting Bd infection status (one high prevalence, one low prevalence and two Bd-free populations), we evaluated whether Bd-positive populations exhibited a higher adult recruitment and a higher male reproductive effort than Bd-negative populations. We also estimated population growth rates to explore whether recruitment compensated for the negative impacts of Bd on the survival of adults. In addition, we evaluated a potential demographic signal of compensatory recruitment (i.e. positive relationship between the proportion of juveniles and Bd prevalence) in response to Bd infection using raw count data from 13 R. darwinii populations. The high Bd prevalence population exhibited the highest male reproductive effort and the highest recruitment among the four monitored populations. This led to a growing population during the study period despite high mortality of adult hosts. In contrast, males from the population with low Bd prevalence had a low reproductive effort and this population, which had the lowest adult recruitment, was declining during the study period despite adults having a higher survival in comparison to the high Bd prevalence population. We also found a demographic signal of compensatory recruitment in response to Bd infection in our broader analysis of 13 R. darwinii populations. Our study underlines the importance of interpopulation variation in life-history strategies on the fate of host populations after infectious disease emergence. Our results also suggest that an increase in reproductive effort can be one of the processes underlying compensatory recruitment in populations of Bd-susceptible amphibians.

Exposure to Batrachochytrium dendrobatidis affects chemical defences in two anuran amphibians, Rana dalmatina and Bufo bufo

BackgroundBatrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis, one of the major causes of worldwide amphibian biodiversity loss. Many amphibians exhibit skin-based chemical defences, which may play an important role against invading pathogens, but whether the synthesis of these chemical compounds is enhanced or suppressed in the presence of pathogens is largely unknown. Here we investigated direct and indirect effects of larval exposure to the globally distributed and highly virulent Bd-GPL strain on skin secreted chemical defences and life history traits during early ontogeny of agile frogs (Rana dalmatina) and common toads (Bufo bufo).ResultsExposure to Bd during the larval stage did not result in enhanced synthesis of the antimicrobial peptide Brevinin-1 Da in R. dalmatina tadpoles or in increased production of bufadienolides in B. bufo tadpoles. However, exposure to Bd during the larval stage had a carry-over effect reaching beyond metamorphosis: both R. dalmatina and B. bufo froglets contained smaller quantities of defensive chemicals than their Bd-naïve conspecifics in the control treatment. Prevalence of Bd and infection intensities were very low in both larvae and metamorphs of R. dalmatina, while in B. bufo we observed high Bd prevalence and infection intensities, especially in metamorphs. At the same time, we did not find a significant effect of Bd-exposure on body mass or development rate in larvae or metamorphs in either species.ConclusionsThe lack of detrimental effect of Bd-exposure on life history traits, even parallel with high infection intensities in the case of B. bufo individuals, is surprising and suggests high tolerance of local populations of these two species against Bd. However, the lowered quantity of defensive chemicals may compromise antimicrobial and antipredatory defences of froglets, which may ultimately contribute to population declines also in the absence of conspicuous mass-mortality events.

Distribution and Genetic Diversity of the Amphibian Chytrid in Japan.

While research on frog chytrid fungus Batrachochytrium dendrobatidis (Bd), an infectious disease that threatens amphibian diversity, continues to advance worldwide, little progress has been made in Japan since around 2010. The reason for this is, which we pointed out in 2009, that the origin of frog chytrid fungus may be in the East Asian region, including Japan based on the Bd ITS-DNA variation, and as few cases of mass mortality caused by this fungus have been observed in wild amphibian populations in Japan, the interest of the Japanese government and the general public in Bd has waned. However, we believe that organizing the data obtained so far in Japan and distributing the status of frog chytrid fungus in Japan to the world will provide useful insight for future risk management of this pathogen. We collected more than 5500 swab samples from wild amphibians throughout Japan from 2009 to 2010. Then, we investigated the infection status using the Nested-PCR method. We sequenced the obtained DNA samples and constructed a maximum-parsimony (MP) tree to clarify the phylogenetic diversity of Bd. We detected Bd infection in 11 (nine native and two alien) amphibian species in Japan and obtained 44 haplotypes of Bd ITS-DNA. The MP tree showed a high diversity of Bd strains in Japan, suggesting that some strains belong to Bd-GPL and Bd-Brazil. Except for local populations of the Japanese giant salamanders Andrias japonicus in Honshu Island and the sword tail newts Cynops ensicauda in Okinawa Island, the Bd infection prevalence in native amphibian species was very low. The alien bullfrog Aquarana catesbeiana had high Bd infection rates in all areas where they were sampled. No Bd infection was detected in other native amphibians in the areas where giant salamanders, sword tail newts, and bullfrogs were collected, suggesting that many native amphibians are resistant to Bd infection. The sword tail newt of Okinawa Island had both the highest infectious incidence and greatest number of haplotypes. The giant salamanders also showed relatively high infection prevalence, but the infected strains were limited to those specific to this species. These two Caudata species are endemic to a limited area of Japan, and it was thought that they may have been refugia for Bd, which had been distributed in Japan Islands for a long time.

Comparison of grain yield and quality of different types of japonica rice cultivars in the northern Jiangsu plain, China

In recent years, an increasing number of different types of japonica rice cultivars have been released in the southern rice region of China. The grain yield and quality of these new cultivars showed significant differences in large scale planting. However, the causes of the differences remain little known. Therefore, three typical types of japonica rice cultivars were used in this study to investigate their grain yield and quality. A scanning calorimeter (DSC), X-ray powder diffractometer (XRD), rapid viscosity analyzer (RVA) and taste analyzer were used to evaluate the cooking and eating properties. The results showed that the yield of non-soft hybrid japonica rice cultivars was significantly higher than that of non-soft inbred japonica rice cultivars and soft inbred japonica rice cultivars. Soft inbred japonica rice cultivars had a low amylose content and moderate protein content, which are the main reasons for the superior cooking and eating quality. In addition, the relative crystallinity of soft inbred japonica rice cultivars was significantly higher than that of non-soft inbred and non-soft hybrid japonica rice cultivars, which is considered the major factor resulting in higher transition temperature and gelatinization enthalpy (ΔHgel). Non-soft hybrid japonica rice cultivars had a higher number of large starch granules than soft inbred and non-soft inbred japonica rice cultivars. The setback value (SB) and breakdown value (BD), indirectly reflecting the cooking and eating quality of the three types of japonica rice cultivars, also confirmed that soft inbred japonica rice cultivars with a low SB value and a high BD value had better palatability than the other two types. This study provides guidance for future plantation of different types of japonica rice cultivars in large rice-producing areas.

Selective Production of 1,3-Butadiene from 1,3-Butanediol over Y2Zr2O7 Catalyst

Abstract The vapor-phase dehydration of 1,3-butanediol (1,3-BDO) to produce 1,3-butadiene (BD) was investigated over yttrium zirconate, Y2Zr2O7, which was prepared through a hydrothermal aging process. 1,3-BDO was initially dehydrated to three unsaturated alcohols, namely 3-buten-2-ol, 3-buten-1-ol, and 2-buten-1-ol, followed by the further dehydration to BD. The catalytic activity of Y2Zr2O7 was strongly dependent on the calcination temperature. Furthermore, the reaction temperature was one of the important factors to produce BD efficiently: the selectivity to BD was increased with increasing reaction temperature up to 375 °C, while coke formation led to catalyst deactivation together with by-product formation at higher temperatures. Y2Zr2O7 catalyst calcined at 900 °C showed a high BD yield of 95% at 375 °C and a time on stream of 10 h.

Oxidative dehydrogenation of n-butene to buta-1,3-diene with novel iron oxide-based catalyst: Effect of iron oxide crystalline structure

• ε-Fe 2 O 3 showed the highest ODH activity among various iron oxide-based catalysts. • The catalytic activity of ε-Fe 2 O 3 was improved by the addition of SiO 2 . • ε-Fe 2 O 3 can be applied to the ODH of cis -but-2-ene as well as but-1-ene. We investigate the effect of the crystalline structure of iron oxide catalysts on oxidative dehydrogenation (ODH) of n-butene. ODH reactions of n-butene were carried out with a fixed-bed flow reactor at 450 °C under a but-1-ene (1-C 4 H 8 ) or cis- but-2-ene ( cis -2-C 4 H 8 )(mL/min)/O 2 (mL/min) flow ratio of 5/2.5. Of the various iron oxide-based catalysts (α-, β-, γ-, ε-Fe 2 O 3 , Fe 3 O 4 , ZnFe 2 O 4 ), ε-Fe 2 O 3 showed the highest ODH activity. To the best of our knowledge, ε-Fe 2 O 3 has never been used for the ODH of n-butene. Moreover, the catalytic performance of ε-Fe 2 O 3 was improved by adding SiO 2 , which is related to the maintenance of its structure and improves its redox property. A high BD selectivity of 65 % and BD yield of 18 % were then obtained for 4 h without deactivation. This catalyst can be applied to the ODH of cis -2-C 4 H 8 and is proposed as the noble high catalytic performance catalyst for the ODH of n-butene.

Inhibition of Batrachochytrium dendrobatidis Infection by Skin Bacterial Communities in Wild Amphibian Populations

Skin-associated bacteria are known to inhibit infection by the fungal pathogen Batrachochytrium dendrobatidis (Bd) in amphibians. It has also been postulated that skin-associated bacterial community is related to Bd infection intensity. However, our understanding of host microbial dynamics and their importance in regulating Bd intensity is limited. We analyzed Bd infection and skin-associated bacteria from two amphibian species, the salamander Ambystoma rivulare and the frog Lithobates spectabilis that co-occurred in a tropical high-altitude site in central Mexico. Sixty-three percent of sampled salamander individuals and 80% of frog individuals tested positive for Bd. Overall, we registered 622 skin-associated bacterial genera, from which 73 are known to have Bd inhibitory effects. These inhibitory taxa represented a relative abundance of 50% in relation to total relative bacterial abundance. Our results indicated that, although sharing some bacterial taxa, bacterial community from the skin of both species was different in taxonomic composition and in relative abundance. Pseudomonas spp. and Stenotrophomonas spp. were among the five most abundant bacterial taxa of both species. Both bacterial taxa inhibit Bd infection. We detected that bacterial richness and relative abundance of inhibitory Bd bacteria were negatively related to intensity of Bd infection independent of species and seasons. Despite the high Bd prevalence in both host species, no dead or sick individuals were registered during field surveys. The relatively low levels of Bd load apparently do not compromise survival of host species. Therefore, our results suggested that individuals analyzed were able to survive and thrive under a dynamic relation with enzootic infections of Bd and their microbiota.

A Political Economy and Voicing Model of the Institutional Impact of Brain Drain, Human Capital, Inequality and Country Size

Brain drain BD, human capital h, and inequality's institutional impact is examined in a model where a rent-seeking elite taxes residents and voicing affects the likelihood of regime change. We find that BD and h's impact on institutional quality (Q) are as follows: i) Q is a U-shaped function of BD, with maximum (minimum) at BD = 0 (0 ) BD1, and is maximized at BD = 0; vi) Q increases in a high (low) BD country under a host country's immigration promotion (restriction); vii) a high BD country's institutions improve (worsen) under a large (small) reduction in BD; viii) the latter is particularly relevant for small and micro states where BD and Q are likely to be greater than in large but otherwise similar countries.

Chytridiomycosis-induced mortality in a threatened anuran

Effectively planning conservation introductions involves assessing the suitability of both donor and recipient populations, including the landscape of disease risk. Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), has caused extensive amphibian declines globally and may hamper reintroduction attempts. To determine Bd dynamics in potential source populations for conservation translocations of the threatened California red-legged frog (Rana draytonii) to Yosemite National Park, we conducted Bd sampling in two populations in the foothills of the Sierra Nevada Mountains, California, U.S.A. At one of two sites, we observed lethally high Bd loads in early post-metamorphic life stages and confirmed one chytridiomycosis-induced mortality, the first such report for this species. These results informed source population site selection for subsequent R. draytonii conservation translocations. Conservation efforts aimed at establishing new populations of R. draytonii in a landscape where Bd is ubiquitous can benefit from an improved understanding of risk through disease monitoring and ex situ infection studies.

Evaluation of Tumor Budding in Predicting Survival for Gastric Carcinoma Patients in Vietnam.

Background:Tumor budding (Bd) has been demonstrated to be a promising prognostic factor in many carcinomas and in gastric cancer. It may represent an optimal additional parameter that is helpful for risk stratification in gastric adenocarcinoma. Hence, the present research was designed to predict the survival outcomes of gastric cancer in Vietnam, applying the tumor budding criteria of the International Tumor Budding Consensus Conference (ITBCC) 2016.Methods:The present study was conducted on 109 gastric cancer patients who underwent surgery but did not receive neo-adjuvant chemotherapy from 2012 to 2015. The patients’ clinicopathological features were recorded. Bd was evaluated according to the 2016 ITBCC criteria and classified as Bd1 (0–4 buds), Bd2 (5–9 buds), and Bd3 (≥10 buds) grades, in addition to being categorized into 2 main Bd groups: low (<10 buds) and high (≥10 buds) Bd. Kaplan–Meier and log-rank models were applied to analyze survival proportions.Results:Of all the patients, 22.9% were classified as Bd1, 31.2% as Bd2, and 45.9% as Bd3 grades. Furthermore, 54.1% patients were categorized into the low and 45.9% into the high Bd groups. Patients with Bd1 and Bd2 grades (the low Bd group) exhibited the best prognosis, with 5-year overall survival (OS) rates of 85.7%, 90.8%, and90.3%, respectively. Patients with Bd3 grade (the high Bd group exhibited the worst prognosis, and none of them lived for 5 years (p < 0.001). Similar to OS rates, disease-free survival (DFS) rates markedly reduced from the Bd1 to Bd3 grade: Bd1, 95.0%; Bd2, 84.7%; and Bd3, 0% (p < 0.001).Conclusion:Patients with different gastric cancer Bd grades exhibited significantly different OS and DFS rates. The present study findings suggest that the ITBCC criteria can be used to stratify Bd for the treatment and prognosis of gastric cancer patients in Vietnam.

Highly Selective Conversion of 1‐Butene to 1,3‐Butadiene under CO2 Atmosphere over an Alumina‐supported Iron‐based Catalyst: The Role of Brønsted Acids and Lewis Acids

AbstractThe conversion of 1‐butene to 1,3‐butadiene (BD) with CO2 is burgeoning as a latent technology, but the low BD selectivity of the current catalysts (≤40 %) is now the bottleneck of this process. Herein, an alumina‐supported iron‐based catalyst with high BD selectivity for the oxidative dehydrogenation of 1‐butene using CO2 was designed and prepared, and the BD selectivity has been improved up to 49 %. Consequently, the turnover frequency has been enhanced to 1.5 times that of the current FeVCrOX/γ‐Al2O3 catalyst. Furthermore, the effect of the acid type and content in the catalysts on their selectivity was identified. The Brønsted acids in the catalysts leaded to the unwanted isomerization reactions, whereas the Lewis acids played a key role in highly selective transform 1‐butene to BD. The BD selectivity increased with the increasing Lewis/Brønsted acids ratio. In addition, the conversion of 1‐butene over such catalysts was investigated through kinetic study.