Desertification models do not include analyses of rainfall, temporality, field visits and projection scenarios. The objective is to evaluate desertification under levels of vegetation, soil and albedo, construct forecast models and analyze its variability with time and rainfall. Landsat TM was used for NDVI, TGSI and albedo between 2000 and 2008 in dry and rainy periods in Irauçuba Centro Norte (ICN) and in the National Forest of Sobral (FLONA). Desertification levels and indices of 30 pixels were quantified and their means were inputs in the ARIMA model. The results showed vegetation and albedo at different levels of desertification. The medium desertification class of NDVI increased by 18% at ICN and the low desertification class of albedo increased by 3%. TGSI showed the class severe at ICN and FLONA. The AR(3) model indicated reduction in NDVI, while MA(1) for TGSI and albedo showed severe and low level. ARMA(2,1) showed optimistic scenario of recovery for pixels with desertified NDVI and Albedo of FLONA. The AR(3) model for TGSI of FLONA showed a reduction of 0.0006504 in 70 years. Anthropic practices and climate were responsible for the desertification of ICN, while FLONA was shown to be non-desertified, but NDVI and TGSI were affected by the anthropic practices. Therefore, desertification showed different levels at ICN, rainfall and time affected vegetation and albedo at ICN and FLONA. ARMA(2,1) models showed that the prospects of desertification reversal are greater for FLONA.
Persian oak decline is a syndrome within the oak decline complex in Iran. Profuse stem bleed-ing and larval galleries of the native buprestid, Agrilus hastulifer characterize the disease. A systematic study comparing healthy with diseased trees was undertaken. This work reports the result of isolations from healthy trees and diseased tissue in affected trees, at eight sites in Iran. Culturable bacterial communities were identified using the 16S rDNA sequencing. A significantly higher proportion of symptomatic tissue pieces from diseased trees (Disease In-dex=5) yielded bacterial growth than other disease indexes (83.78%). Significantly higher yields were also obtained from bulk and rhizosphere compared with the root, leaf, and stem. Overall bacterial communities compositions varied at each site, but significant similarities were evident in diseased tissues at all sites. Enterobacteriaceae were dominated in diseased trees whereas Bacilluceae and Moraxellaceae were remarkable more abundant in healthy trees. Sig-nificant associations occurred between diseased tissues and certain bacterial species, implying that the cause of tissue necrosis was not due to random microbiota. Brenneria goodwinii, Ser-ratia marecescence, and Dickeya chrysanthemi were key species consistently isolated from diseased tissue; Campylobacter jejuni and an un-named Clostridium taxon were also frequent-ly isolated from both healthy and diseased trees. It was concluded that there was a shift in the cultivatable bacterial microbiome of diseased trees, with Enterobacteriaceae strongly repre-sented in symptomatic but not healthy tissues. No single dominated species was isolated from diseased tissues, so tissue degradation in oak likely have a polymicrobial cause.
We have recently described a non-chromatographic, ligand-free approach for antibody (Ab) purification based on specially designed: [Tween-20:bathophenanthroline:Fe2+] aggregates. To assess the potential generality of this approach, a variety of detergents belonging to four nonionic detergent families (Tween, Brij, Triton and Pluronic) have now been studied. All surfactant aggregates lead to high purity of the recovered Abs (>95%, by gel densitometry). Good overall Ab recovery yields were observed with: Tween-20 (80-83%), Brij-O20 (85-87%) and Triton X-100 (87-90%), while Pluronic F-127 was less efficient (42-53%). Of additional importance is the finding that the process can depend on filtration (rather than centrifugation), thereby allowing a continuous purification mode that leads to the recovery of monomeric IgG’s (by DLS) and preservation of Ab specificity (by ELISA). The amphiphilic chelator, bathophenanthroline (batho) is recycled almost quantitatively (95%) by crystallization. Good IgG recovery yields (~80%) are also observed when Ab concentrations are increased from 1 mg/ml to 3-5 mg/mL. Potential advantages of the purification platform for industrial downstream processing of therapeutic monoclonal antibodies (mAbs), are discussed.
In the current research chor, we are reporting the synthesis of 2-amino-6-methylpyrimidin-4-yl benzenesulfonate (AMPBS) and 2,6-diaminopyrimidin-4-yl benzenesulfonate (DAPBS) via O-benzenesulfonylation of 2-amino-6-methylpyrimidin-4-ol 1 and 2,6-diaminopyrimidin-4-ol 2 respectively. The structures of the synthesized compounds were characterized unambiguously by single crystal analysis (SC-XRD).Hirshfeld surface study showed that C-H…O, C-H…N and especially C-H…C hydrogen bond interactions are the key contributors to the intermolecular stabilisation in the crystal. The quantum chemical understanding about optimized geometry, natural bond orbitals (NBOs), frontier molecular orbitals (FMOs) and nonlinear optical (NLO) analysis for AMPBS and DAPBS were obtained by applying density functional theory (DFT) at B3LYP level and 6-311G(d,p) basis set. Time dependent density functional theory (TD-DFT)/ B3LYP/ 6-311G(d,p) level were employed to determine the photo physical properties of compounds. As a whole, the simulated results were found to have an excellent concurrence to the experimental results. The charge transfer phenomenon entitled compounds was determined by FMOs. Global reactivity parameters were obtained by using HOMO–LUMO energies of compounds. Overall, the computational results of AMPBS and DAPBS have outstanding agreement to experimental data. The computational study also showed that the title compounds have remarkable NLO properties.
Background and Purpose: Minimal hepatic encephalopathy (MHE) is implicated in the impairment of memory function. Fibroblast growth factor-2 (FGF2) is involved in modulating synaptic and neuronal formation. Experimental Approach: The aim of this study is to examined the impacts of FGF2 on MHE pathology. Our study addressed whether FGF2 could trigger neuregulin 1 (NRG1) release to ameliorate synaptic impairment in MHE rats and in primary cultured neurons. Key Results: The results showed the decreased FGF2 expression in MHE brains. After treatment with FGF2, secreted neuregulin 1 (NRG1) and ErbB4 were increased, and the interaction of the 2 proteins was enhanced. Additionally, treatment with FGF2 or NRG1 induced synaptic formation, with increase in the activity of synapse and the density of dendritic spine, through Sirt1. NRG1 signaling was prevented by administration of FGF2, which acts through the FGFR1 in MHE rats. Finally, intracerebroventricular injection with FGF2 or NRG1 mitigated the impairment of synaptogenesis. Conclusions and Implications: The data suggest that FGF2 may be a promising latent therapeutic reagent for MHE pathogenesis.
There is not any medicine during the emergency of 2019-nCov has been an outbreak and we have already found antiviral phytomedicine Chinese elderberry will be inhibition of 2019-nCoV.This commentary used to be presented in June of 2013 at the first international symposium for the elderberry, the conference, held in the USA, many scientists were surprised to learn of the 9 native species of elderberry in China. This paper aims to publish our comment on the elderberry, as, since our initial presentation in 2013, no English literature references are present in China. Most Chinese horticulturists and farmers consider the elderberry a wild plant. It is regarded as a plant of little value due to its abundance and ease of harvest. This article contains details of the Sambucus species groups, including the botanical names, Chinese common names, geographic distributions, economic uses and full descriptions of the elderberry. In southwest China, where the climate is mildly warm, there are 2 species of elderberries; one, Sambucus adnata, is termed the “blood-red herb-elderberry” by local residents as the roots, rhizomes, and branches exude red-juice when broken. The second, named S. javanica or S. chinensis, is commonly called the “herb-elderberry”. In northeast China where the climate is cold, there are 7 species of elderberry, however, most scientists recognize only 2 main species: Sambucus. williamsii, commonly called the “woody-elderberry”, and Sambucus sibirica, commonly called the “Siberian woody-elderberry”. The other 5 species of elderberry in northern-east of China.
L-lysine amino acid is cocrystallized with L-mandelic acid by the slow evaporation method. Single crystal X-ray analysis reveals that lysine-mandelic acid crystallized as a dihydrate form. In the crystalline state, the lysine molecule exists in the cationic form in which the backbone and side chain amino groups are protonated and the carboxylic acid is deprotonated. The carboxylic acid proton of the mandelic acid is transferred to the lysine side chain and thus carries a negatively charged ion. The lattice water molecules are located near the amino groups of the lysine. Intermolecular interactions formed between lysinium, mandelate and lattice water molecules are qualitatively analyzed using Hirshfeld surfaces and 2D-fingerprint plots. The energetics of different dimeric complexes is quantitatively analyzed using PIXEL energy analysis. Topological parameters derived from QTAIM framework are used to delineate the nature of different intermolecular interactions formed in the title complex.
1. Global warming is rapidly emerging as a universal threat that could alter the distribution of many animal species and change their morphology, physiology, behavior and life history. The heat dissipation limitation (HDL) hypothesis proposes that females’ reproductive performance is limited by their capacity to dissipate heat. Although exposure to wind is known to increase heat exchange, its effect on reproductive performance is unknown. 2. In this study, the effect of simulated wind on the energy budget and milk energy output of female striped hamsters (Cricetulus barabensis) was measured under cool (21°C) and hot (32.5°C) ambient temperatures and the preference of hamsters for windy conditions in lactating females was tested both in the laboratory and the wild. 3. Females lactating at 32.5°C significantly decreased their energy intake and milk output, and raised lighter offspring than those lactating at 21°C. Exposure to wind significantly increased both energy intake during lactation and heat loss at both temperatures. Females lactating at 32.5°C considerably increased their reproductive output when exposed to wind. Moreover, females kept at an ambient temperature of 21°C preferred sheltered conditions whereas those kept at 32.5°C preferred exposure to simulated wind. We captured significantly more lactating female hamsters on windy days in summer and on calm days in spring. Wrapping a glass vessel in the fresh pelt of a striped hamster significantly reduced the rate of both water loss and cooling. 4. These findings support the HDL hypothesis; high ambient temperatures do appear to limit the energy intake and reproductive output of lactating hamsters. Small mammals lactating under hot conditions may be able to utilize the cooling properties of wind to increase their energy intake and milk production, and thereby their reproductive output and fitness.
his study describes the response of Arthrospira platensis to a variety of temperature conditions as reflected in variations of photosynthetic parameters, pigmentation, and biomass productivity in indoor photobioreactor (PBR) cultivations. These experiments are designed to better understand the impact of temperature, seasonal variations, and acclimation effects on outdoor biomass production. The irradiance levels and temperature range (20 – 39°C) are chosen to enable modeling of semi-continuous operation of large-scale outdoor PBR deployments. Overall, the cultivations were quite stable with some pigment-related instabilities after prolonged high temperature exposure. Changes in productivity with temperature, as reflected in measured photosynthetic parameters, are immediate and mainly attributable to the temperature dependence of the photosaturation parameter, a secondary factor being variation in pigment content. This study confirms that temperature is critical for optimal performance of Arthospira platensis for both biomass and pigment production and provides a basis for risk assessments related to temperature mitigation for large-scale outdoor cultivations. Finally, the biomass productivities in a semi-continuous operation mode are quantitatively reproduced with a productivity model incorporating the photosynthetic parameters measured herein. Those productivities are in good agreement with extensive outdoor testing in PBR arrays at large scale (24,000 L) and over long time periods (up to 18 months).
This DFT study treats thermal metal-catalyzed alkene aziridination by azides, where the catalysts are copper(II) triflate, cobalt(II) porphin and ruthenium(II) porphin. Three azides RN3 (R = H, Me, Ac) react with alkene substrates in the presence of these catalysts leading to aziridine formation by a two-step catalysed mechanism. In Step I, the azide reacts with the catalyst to first form a metal nitrenoid via transition state TS1. The Ru(porph) catalyst is particularly effective for Step I. In Step II, the metal nitrenoid adds to the alkene via TS2 giving the aziridine product. Cu(trfl)2 is most effective as a catalyst for Step II. The facility order H > Me > Ac (with respect to the azide R group) holds for Step I, and the reverse order for Step II. Transition states TS1 and TS2 are described as “early” and “late”, respectively, in good accord with Hammond’s postulate.
Single-nucleotide polymorphisms (SNPs) have numerous advantages over microsatellites, including greater power to infer population structure and history and to detect loci undergoing selection. Here, we conduct the first continental-level SNP study of polar bears (Ursus maritimus) using genotypes from an array of 5441 SNP loci genotyped in 16–30 polar bears sampled in each of 16 geographic regions in Canada and West Greenland. Our study aimed to assess population history and genetic structure and to identify evidence of adaptive loci. Using these data, we confirmed the existence of four broad-scale genetic clusters in North America (FCT = 0.035) and identified nine fine-scale subclusters using more powerful spatial methods. An assessment of historical patterns of migration suggests that polar bears migrated into North America from the Beaufort Sea after the last glacial maximum. Using a conservative approach, we identified 17 loci that may represent adaptive variation, including one SNP in the 3’ untranslated region of PDLIM5 (PDZ And LIM Domain 5), a gene involved in cardiovascular function, which has undergone substantial selection in polar bears since their divergence from brown bears. Outlier loci differentiated the Norwegian Bay genetic cluster more strongly from remaining clusters than did our complete dataset, suggesting possible adaptive differences in the High Arctic. Through careful consideration of SNP loci, sample inclusion, and analytical approaches, we provide a comprehensive picture of polar bear population structure at a continental level. This study provides a model for the analysis of wide-ranging species that can contribute to their conservation and management.
In this paper we are interested in two-dimensions fragmentation process that describes the evolution of an object having a rectangular shape. We focus on the non-homogenous fragmentation process where we break a rectangle according to a distribution that depends on its dimensions. Via Integral equations tools, we compute the mean and the variance of the distribution of the total number of the sub-rectangles obtained at the end of the process.
Although photodynamic therapy (PDT) is an effective, minimally-invasive therapeutic modality with advantages in highly localized and specific tumor treatments, large and deep-seated cancers within the body cannot be successfully treated due to low transparency to visible light. To improve the therapeutic efficiency of tumor treatment in deep tissue and reduce the side effects in normal tissue, this study developed a near-infrared (NIR)-triggered upconversion nanoparticle (UCNP)-based photosensitizer (PS) carrier as a novel theranostics system. The NaYF4:Yb/Er UCNPs were synthesized by a hydrothermal method, producing uniformly small size (≈20 nm) nanoparticles and crystalline morphology of the hexagonal phase. These UCNPs were modified with folic acid-conjugated biocompatible block copolymers through a bidentate dihydrolipoic acid linker. The polymer modified hexagonal phase UCNPs (FA-PEAH-UCNPs) showed an improved dispersibility in the aqueous solution and strong NIR-to-vis upconversion fluorescence. The hydrophobic PS, pheophorbide a (Pha), was then conjugated to the stable vectors through a pH-sensitive linkage. Moreover, these UCNP-based Pha carriers containing tumor targeting folic acid ligands exhibited the significantly enhanced cellular uptake efficiency as well as PDT treatment efficiency. These results suggested that this system could extend the excitation wavelength of PDT to the NIR region and effectively improve therapeutic efficiency of PSs.
The biodiverse Neotropical ecoregion remains insufficiently assessed, poorly managed, and threatened by unregulated human activities. Novel, rapid and cost-effective DNA-based approaches are valuable to improve understanding of the biological communities and for biomonitoring in remote areas. Here, we evaluate the potential of environmental DNA (eDNA) metabarcoding for assessing the structure and distribution of fish communities by analysing sediments and water from 11 locations along the Jequitinhonha River catchment (Brazil). Each site was sampled twice, before and after a major rain event in a five-week period and fish diversity was estimated using high-through-put sequencing of 12S rRNA amplicons. In total, 252 Molecular Operational Taxonomic Units (MOTUs) and 34 fish species were recovered, including endemic, introduced, and previously unrecorded species for this basin. Spatio-temporal variation of fish assemblages was detected, richness during the first campaign was nearly twice as high as in the second sampling round; though peaks of diversity were primarily associated with only four locations. No correlation between β-diversity and longitudinal distance or presence of dams was detected, but low species richness observed at sites located near dams indicates that these anthropogenic barriers might have an impact on local fish diversity. Unexpectedly high α-diversity levels recorded at the river mouth suggest that these sections should be further evaluated as putative “eDNA reservoirs” for rapid monitoring. By uncovering spatio-temporal changes, unrecorded biodiversity components, and putative anthropogenic impacts on fish assemblages, we further strengthen the potential of eDNA metabarcoding as a biomonitoring tool, especially in regions often neglected or difficult to access.
Acquired drug resistance syndrom (ADR) is one of the most important features associated with tumor treatment and it is therefore a~topic of intensive studies. We present two simple mathematical models reflecting different mechanisms of ADR with some Darwinian effects included. These effects allow resistant cells to become sensitive again. Basing on this mathematical approach we conclude that for constant continuous treatment, if no Darwinian effects are present then once resistant cells appear, sensitive cells are eliminated after a long time, independently of the mechanism of acquiring the resistance. However, with Darwinian effects the situation is a little better as the sensitive cells are not completely eliminated but they are still outcompeted by the resistant ones. Moreover, if the therapy is stopped resistant cells become dominated by sensitive cells and the situation changes completely in comparison to the case without Darwinian effects. We discuss these mechanisms on the example of gliomas.
The formulation and analysis of two operator Boundary-Domain Integral Equation systems for variable coefficient mixed BVP with in two dimensional domain is discussed. To analyse the two-operator approach, we applied one of its linear versions to the mixed (Dirichlet-Neumann) BVP for a linear second-order scalar elliptic variable-coefficient PDE and reduced it to four different BDIE systems. %The two-operator BDIE systems are nonstandard systems of equations containing integral operators defined on the domain under consideration and potential type and pseudo-differential operators defined on open sub-manifolds of the boundary. Using the results as in CMN09 andAM11, a rigorous analysis of the two-operator BDIE systems is given and it is shown that they are equivalent to the mixed BVP and thus are uniquely solvable, while the corresponding boundary domain integral operators are invertible in the appropriate Sobolev-Slobodetski (Bessel potential) spaces.
Primary biliary cholangitis (PBC) is an immune-mediated chronic cholestasis. The disruption of T cell homeostasis plays an important role in PBC pathogenesis. Lysosomal associated membrane protein 2 isoform A (LAMP-2A) has been implicated in the regulation of CD4+ T cell responses, therefore we aim to evaluate the activation state of CD4+ T cells in PBC, and to investigate the role of LAMP-2A in it. The peripheral blood of PBC patients (PBC, n=42) and healthy controls (HC, n=20) were phenotypically analyzed, and LAMP-2A expression in CD4+ T cells was assessed by flow cytometry. Naïve CD4+ T cells of PBC patients were isolated and activated in vitro to estimate their activation responses. Additionally, we assessed the changes induced by silencing LAMP-2A expression. We found that CD4+ T cells of PBC patients exhibited significant hyperactivity, and naïve CD4+ T cells showed high LAMP-2A expression, which could be a novel biomarker for PBC activity. Moreover, by interfering with LAMP-2A expression in vitro, the overreactions of PBC naïve CD4+ T cells were reversed. Our study will help to clarify that increased LAMP-2A expression in the naïve CD4+ T cells of PBC patients may lead to a tendency for increased activation responses, which may be involved in the development and progression of PBC. To reverse the hyperactivity of CD4+ T cells and reduce the resulting biliary injury, LAMP-2A could be a novel therapeutic target for the treatment of PBC.
Mycorrhizal fungi alter their host plant’s resistance to herbivores and their competitive ability. However, most studies on how mycorrhizae alter resistance have been conducted in single plant studies, and so the interacting effects of mycorrhizae and competition on constitutive and induced plant resistance is largely unexplored. We tested whether mycorrhizal colonization with Rhizophagus intraradice would alter herbivore performance and the expression of chemical resistance traits in tomato plants with and without intraspecific competition. We treated the plants with jasmonic acid to measure their induced chemical resistance traits which we evaluated by measuring leaf consumption by Trichoplusia ni caterpillars and two traits that affect herbivore performance: protease inhibitors, an antinutritive protein, and carbon/nitrogen ratio, a metric of plant nutritional quality. Mycorrhizae decreased resistance (increased leaf consumption) to herbivores when the plants were not in competition but had no effect in competition. While mycorrhizae reduced protease inhibitors, independent of competition or treatment with jasmonic acid, this did not increase caterpillar feeding. However, mycorrhizae, competition and induction with jasmonic acid interacted to decrease plant nutrition, measured as C/N ratio, which was correlated with caterpillar feeding. Here, we show that mycorrhizae induced decreases in plant nutritional quality; a novel mechanism by which mycorrhizae affect resistance to herbivores. Mycorrhizae and competition interact to decrease plant nutritional quality and alter resistance to herbivores.