Molluscicidal Activity of Some Solanum Species Extracts against the Snail Biomphalaria alexandrina

Background. Snails' species are associated with transmission parasitic disease as intermediate host. Biological control stands to be a better alternative to the chemical controls aimed against snails. The search of herbal preparations that do not produce any adverse effects in the non-target organisms and are easily biodegradable remains a top research issue for scientists associated with alternative molluscicides control. Method. Solvent extracts of fresh mature leaves of S. nigrum, S. villosum, and S. sinaicum were tested against Biomphalaria alexandrina, a common intermediate host of schistosoma mansoni. A phytochemical analysis of chloroform: ethanol extract was performed to search for active toxic ingredient. The lethal concentration was determined. Results. Extracts isolated from mature leaves of Solanum species were found to be having molluscicidal properties. S. nigrum extract was recorded as the highest mortality rate. When the mortality of different solvent extracts was compared, the maximum (P < .05) mortality was recorded at a concentration of 90 ppm of ethanol extract of S. nigrum. Conclusion. Extract of mature leaves of S. nigrum exhibited molluscicidal activity followed by S. sinaicum and the less one was S. villosum. The study provides considerable scope in exploiting local indigenous resources for snails' molluscicidal agents

Učinak opuštanja na prekidačka svojstva tankih slojeva CuInSeTe

The switching properties of amorphous CuInSeTe thin films have been investigated. The amorphous quaternary semiconductor CuInSeTe thin films ∼ 220 nm and ∼ 330 nm thick have been prepared by thermal evaporation of the bulk compound under vacuum of about 10−4 Pa and with deposition rate about 8 nm/s. The structure of the bulk and thin films were investigated by the X-ray diffraction technique. The compositional studies of CuInSeTe in both powder and thin films were carried out by Perkin Elmer Model 1100 atomic absorption spectrometer. The annealing of the films at different annealing temperatures (300, 350, 400, 450 and 500 K) improves the switching characteristics and decrease the threshold voltage Vth. The threshold switching voltage and the threshold activation energy Es were found to decrease linearly with increasing annealing temperature. Moreover, the threshold switching voltage decreased exponentially with temperature.Istraživali smo prekidačka svojstva amorfnih tankih slojeva CuInSeTe. Tanke amorfne slojeve četiritvornog poluvodiča CuInSeTe debljine ∼ 220 nm i ∼ 330 nm pripremali smo naparavanjem spoja u vakuumu pri oko 10−4 Pa, brzinom naparavanja od oko 8 nm/s. Strukturu praha i tankih slojeva odredili smo rendgenskom difrakcijom. Sastav CuInSeTe u prahu i tankih slojeva ispitali smo pomoću Perkin Elmer-ovog (model 1100) apsorpcijskog spektrometra. Opuštanje tankih slojeva na nizu temperatura (300, 350, 400, 450 i 500 K) poboljšava njihova preklopna svojstva i smanjuje napon praga preklopnog napona Vth. Našli smo da se prag preklopnog napona i prag aktivacijske energije Es linearno smanjuju s povećanjem temperature opuštanja. K tome, prag preklopnog napona smanjuje se eksponencijalno s temperaturom opuštanja

Correlated decay of triplet excitations in the Shastry-Sutherland compound SrCu2_2(BO3_3)2_2

The temperature dependence of the gapped triplet excitations (triplons) in the 2D Shastry-Sutherland quantum magnet SrCu$_2$(BO$_3$)$_2$ is studied by means of inelastic neutron scattering. The excitation amplitude rapidly decreases as a function of temperature while the integrated spectral weight can be explained by an isolated dimer model up to 10~K. Analyzing this anomalous spectral line-shape in terms of damped harmonic oscillators shows that the observed damping is due to a two-component process: one component remains sharp and resolution limited while the second broadens. We explain the underlying mechanism through a simple yet quantitatively accurate model of correlated decay of triplons: an excited triplon is long-lived if no thermally populated triplons are near-by but decays quickly if there are. The phenomenon is a direct consequence of frustration induced triplon localization in the Shastry--Sutherland lattice.Comment: 5 pages, 4 figure

On Fields with Finite Information Density

The existence of a natural ultraviolet cutoff at the Planck scale is widely expected. In a previous Letter, it has been proposed to model this cutoff as an information density bound by utilizing suitably generalized methods from the mathematical theory of communication. Here, we prove the mathematical conjectures that were made in this Letter.Comment: 31 pages, to appear in Phys.Rev.

A Monitoring System for Crimean Congo Hemorrhagic Fever Epidemiology Studies in Afghanistan

In the last few years, tick-borne diseases have been reported as a resurging in the Middle East. Crimean-Congo hemorrhagic fever (CCHF) is endemic in the Middle East, including Turkey, Iran, Afghanistan and Pakistan. Recent studies have explored the causal link between environmental and disease incidence patterns by correlating remote sensing indicators (surface temperature, rainfall, and vegetation indices of plant photosynthetic activity) with spatially explicit epidemiological data. We combined the monitoring of environmental data at monthly temporal resolutions with available reports of confirmed CCHF cases to identify the environmental properties of endemic regions and quantify those properties to CCHF risk. We also conducted a sero-prevalence survey in a sample of households (human and animal specimens) in 9 villages in Engil district surrounding Herat province, in western Afghanistan. We present analysis results from our study villages and validate the associated environmental conditions as predictive for human disease occurrences. Risk prediction is critical for anticipating the type and potential impact of disease threats for timely response action

Cognitive appraisal of environmental stimuli induces emotion-like states in fish

The occurrence of emotions in non-human animals has been the focus of debate over the years. Recently, an interest in expanding this debate to non-tetrapod vertebrates and to invertebrates has emerged. Within vertebrates, the study of emotion in teleosts is particularly interesting since they represent a divergent evolutionary radiation from that of tetrapods, and thus they provide an insight into the evolution of the biological mechanisms of emotion. We report that Sea Bream exposed to stimuli that vary according to valence (positive, negative) and salience (predictable, unpredictable) exhibit different behavioural, physiological and neuromolecular states. Since according to the dimensional theory of emotion valence and salience define a two-dimensional affective space, our data can be interpreted as evidence for the occurrence of distinctive affective states in fish corresponding to each the four quadrants of the core affective space. Moreover, the fact that the same stimuli presented in a predictable vs. unpredictable way elicited different behavioural, physiological and neuromolecular states, suggests that stimulus appraisal by the individual, rather than an intrinsic characteristic of the stimulus, has triggered the observed responses. Therefore, our data supports the occurrence of emotion-like states in fish that are regulated by the individual's perception of environmental stimuli.European Commission [265957 Copewell]; Fundacao para a Ciencia e Tecnologia [SFRH/BD/80029/2011, SFRH/BPD/72952/2010]info:eu-repo/semantics/publishedVersio

Compromised BRCA1-PALB2 interaction is associated with breast cancer risk.

The major breast cancer suppressor proteins BRCA1 and BRCA2 play essential roles in homologous recombination (HR)-mediated DNA repair, which is thought to be critical for tumor suppression. The two BRCA proteins are linked by a third tumor suppressor, PALB2, in the HR pathway. While truncating mutations in these genes are generally pathogenic, interpretation of missense variants remains a challenge. To date, patient-derived missense variants that disrupt PALB2 binding have been identified in BRCA1 and BRCA2; however, there has not been sufficient evidence to prove their pathogenicity in humans, and no variants in PALB2 that disrupt either its BRCA1 or BRCA2 binding have been reported. Here we report on the identification of a novel PALB2 variant, c.104T>C (p.L35P), that segregates in a family with a strong history of breast cancer. Functional analyses showed that L35P abrogates the PALB2-BRCA1 interaction and completely disables its abilities to promote HR and confer resistance to platinum salts and PARP inhibitors. Whole-exome sequencing of a breast cancer from a c.104T>C carrier revealed a second, somatic, truncating mutation affecting PALB2, and the tumor displays hallmark genomic features of tumors with BRCA mutations and HR defects, cementing the pathogenicity of L35P. Parallel analyses of other germline variants in the PALB2 N-terminal BRCA1-binding domain identified multiple variants that affect HR function to varying degrees, suggesting their possible contribution to cancer development. Our findings establish L35P as the first pathogenic missense mutation in PALB2 and directly demonstrate the requirement of the PALB2-BRCA1 interaction for breast cancer suppression

Developmental plasticity shapes social traits and selection in a facultatively eusocial bee

Developmental plasticity generates phenotypic variation, but how it contributes to evolutionary change is unclear. Phenotypes of individuals in caste-based (eusocial) societies are particularly sensitive to developmental processes, and the evolutionary origins of eusociality may be rooted in developmental plasticity of ancestral forms. We used an integrative genomics approach to evaluate the relationships among developmental plasticity, molecular evolution, and social behavior in a bee species (Megalopta genalis) that expresses flexible sociality, and thus provides a window into the factors that may have been important at the evolutionary origins of eusociality. We find that differences in social behavior are derived from genes that also regulate sex differentiation and metamorphosis. Positive selection on social traits is influenced by the function of these genes in development. We further identify evidence that social polyphenisms may become encoded in the genome via genetic changes in regulatory regions, specifically in transcription factor binding sites. Taken together, our results provide evidence that developmental plasticity provides the substrate for evolutionary novelty and shapes the selective landscape for molecular evolution in a major evolutionary innovation: Eusociality