Dinâmica populacional da mosca-dos-chifres no Pantanal.

Durante dois anos, de junho/93 a maio/95, contagens de moscas-dos-chifres foram realizadas em dois rebanhos Nelore criados extensivamente na fazenda Nhumirim, sub-região da Nhecolândia, Pantanal, MS. Os rebanhos possuíam 40 e 60 vacas, mantidas sem tratamento inseticida durante o estudo. Contagens foram realizadas duas semanas consecutivas por mês, por observadores a cavalo, em pelo menos 50% dos animais em cada rebanho. Foram observados dois picos populacionais anuais da mosca, após o início (novembro/dezembro) e final (maio/junho) do período chuvoso. A presença de moscas foi observada durante todo o estudo, em pelo menos 64% dos animais. Infestações médias não excederam 85 moscas/animal e permaneceram abaixo de 35 moscas/animal na maior parte do estudo. Entretanto, infestações acima de 300 moscas foram observadas individualmente. Altas infestações apresentaram curta duração, com acentuada redução no número de moscas em até duas semanas. Os resultados obtidos neste estudo indicam que o controle "estratégico" (tratamento em épocas pré-definidas) da mosca-dos-chifres na região deve prever dois tratamentos anuais, após o início (novembro) e final (maio) da época chuvosa. O controle "tático" (tratamento quando necessário) pode ser eventualmente realizado neste intervalo em função de infestações que efetivamente causem incômodo aos animais.bitstream/item/37421/1/BP31.pd

Comercialização e uso de produtos inseticidas para controle da mosca-dos-chifres em Aquidauana, MS.

A mosca-dos-chifres é considerada um sério problema econômico à pecuária devido aos prejuízos causados à produção e gastos com controle. Este estudo objetivou conhecer o perfil da comercialização e uso dos produtos inseticidas para controle da mosca-dos-chifres no município de Aquidauana, MS. De nov/1999 a nov/2000, informações foram obtidas em estabelecimentos agropecuários na cidade de Aquidauana e em entrevistas com produtores rurais e gerentes de fazendas. Um total de 29 produtos indicados para o controle da mosca foram encontrados nos estabelecimentos, pertencentes aos grupos dos piretróides (58,6%), organofosforados (3,4%), fenil pirazoles (3,4%), lactonas macrocíclicas (3,4%) e associações entre inseticidas (31,0%). A cipermetrina foi o princípio ativo mais comum, presente em 69,0% dos produtos (incluindo associações). Informações obtidas em 212 propriedades evidenciaram uma ampla utilização de produtos piretróides, empregados rotineiramente em 89,6% das propriedades, a maioria dos quais à base de cipermetrina (69,8%) e deltametrina (48,1%). A utilização de produtos de outras classes inseticidas é mínima. O domínio dos produtos piretróides, em termos de comercialização e uso no município de Aquidauana, explica os crescentes problemas de controle da mosca-dos-chifres e o desenvolvimento de resistência a inseticidas desta classe.bitstream/item/37420/1/BP32.pd

Two-Dimensional Electronic Spectroscopy of Chlorophyll a: Solvent Dependent Spectral Evolution

The interaction of the monomeric chlorophyll Q-band electronic transition with solvents of differing physical-chemical properties is investigated through two-dimensional electronic spectroscopy (2DES). Chlorophyll constitutes the key chromophore molecule in light harvesting complexes. It is well-known that the surrounding protein in the light harvesting complex fine-tunes chlorophyll electronic transitions to optimize energy transfer. Therefore, an understanding of the influence of the environment on the monomeric chlorophyll electronic transitions is important. The Q-band 2DES is inhomogeneous at early times, particularly in hydrogen bonding polar solvents, but also in nonpolar solvents like cyclohexane. Interestingly this inhomogeneity persists for long times, even up to the nanosecond time scale in some solvents. The reshaping of the 2DES occurs over multiple time scales and was assigned mainly to spectral diffusion. At early times the reshaping is Gaussian-like, hinting at a strong solvent reorganization effect. The temporal evolution of the 2DES response was analyzed in terms of a Brownian oscillator model. The spectral densities underpinning the Brownian oscillator fitting were recovered for the different solvents. The absorption spectra and Stokes shift were also properly described by this model. The extent and nature of inhomogeneous broadening was a strong function of solvent, being larger in H-bonding and viscous media and smaller in nonpolar solvents. The fastest spectral reshaping components were assigned to solvent dynamics, modified by interactions with the solute

HIV-1 evades a Gag mutation that abrogates killer cell immunoglobulin-like receptor binding and disinhibits natural killer cells in infected individuals with KIR2DL2⁺/HLA-C*03: 04⁺ genotype

HIV–1 sequence variations impact binding of inhibitory killer cell immunoglobulin-like receptors (KIRs) to human leucocyte class I (HLA–I) molecules modulating NK cell function. HIV–1 strains encoding amino acids that mediate binding of inhibitory KIRs might therefore have a selective benefit in individuals expressing the respective KIR/HLA genotypes. Here we demonstrate that HIV–1 clade C avoids a p24 Gag mutation that abolishes binding of KIR2DL2 to HLA–C*03:04 and disinhibits NK cells in individual encoding for this genotype

Water Dynamics at Protein Interfaces: Ultrafast Optical Kerr Effect Study

The behavior of water molecules surrounding a protein can have an important bearing on its structure and function. Consequently, a great deal of attention has been focused on changes in the relaxation dynamics of water when it is located at the protein surface. Here we use the ultrafast optical Kerr effect to study the H-bond structure and dynamics of aqueous solutions of proteins. Measurements are made for three proteins as a function of concentration. We find that the water dynamics in the first solvation layer of the proteins are slowed by up to a factor of 8 in comparison to those in bulk water. The most marked slowdown was observed for the most hydrophilic protein studied, bovine serum albumin, whereas the most hydrophobic protein, trypsin, had a slightly smaller effect. The terahertz Raman spectra of these protein solutions resemble those of pure water up to 5 wt % of protein, above which a new feature appears at 80 cm–1, which is assigned to a bending of the protein amide chain

Where constructionism and critical realism converge: interrogating the domain of epistemological relativism

The paper interrogates the status, nature and significance of epistemological relativism as a key element of constructionism and critical realism. It finds that epistemological relativism is espoused by authorities in critical realism and marginalized or displaced in the field of management and organization studies, resulting in forms of analysis that are empirically, but not fully critically, realist. This evaluation prompts reflection on the question of whether, how and with what implications epistemological relativism might be recast at the heart of critical realist studies of management and organization

Integrated genomics and proteomics define huntingtin CAG length-dependent networks in mice.

To gain insight into how mutant huntingtin (mHtt) CAG repeat length modifies Huntington's disease (HD) pathogenesis, we profiled mRNA in over 600 brain and peripheral tissue samples from HD knock-in mice with increasing CAG repeat lengths. We found repeat length-dependent transcriptional signatures to be prominent in the striatum, less so in cortex, and minimal in the liver. Coexpression network analyses revealed 13 striatal and 5 cortical modules that correlated highly with CAG length and age, and that were preserved in HD models and sometimes in patients. Top striatal modules implicated mHtt CAG length and age in graded impairment in the expression of identity genes for striatal medium spiny neurons and in dysregulation of cyclic AMP signaling, cell death and protocadherin genes. We used proteomics to confirm 790 genes and 5 striatal modules with CAG length-dependent dysregulation at the protein level, and validated 22 striatal module genes as modifiers of mHtt toxicities in vivo

Registration of ICGV-SM 86715 Peanut Germplasm

ICGV-SM 86715 (Reg. no. GP-89, PI 598133), an improved Virginia peanut (Arachis hypogaea L. subsp. hypogaea var. hypogaea) germplasm line, was developed by the SADC/ICRISAT (Southern African Development Community/International Crops Research Institute for the Semi-Arid Tropics) Groundnut Project in Malawi. It was released in 1992 as 'Veronica' for pure stand cultivation in Mauritius by the Mauritius Sugar Industry Research Institute (MSIRI), Reduit, Mauritius (5). It has resistance to rust (caused by Puccinia arachidis Speg.), late leafspot [caused by Phaeoisariopsis personata (Berk. & M.A. Curtis) Arx; syn. Cercosporidium personatum (Berk. & M.A. Curtis) Deighton], and pepper spot [caused by Leptosphaerulina crassiasca (Sechet) C.R. Jackson & D.K. Bell]. It was also found free from early leafspot (caused by Cercospora arachidicola S. Hori) in Mauritiu

Prevalence and determinants of anxiety and stress in the general population during COVID-19 pandemic in Iraq: A cross-sectional study

Background The COVID-19 pandemic and its prevention and control measures, such as social distancing, self-isolation, and quarantine, have a negative impact on the population’s mental health. This study aimed to determine the prevalence of anxiety and stress among the general population during the outbreak of COVID-19 and assess their associated factors. Methods We carried out a cross-sectional study in Erbil governorate, Iraqi Kurdistan Region, from July 18 to September 12, 2020. We used an online survey questionnaire to collect data from a sample of Erbil population. The 10-items Perceived Stress Scale and the 7-item Generalized Anxiety Disorder scale were used to measure the levels of stress and anxiety. Results A total of 851 persons responded to the survey. The prevalence of moderate and high perceived stress was 59.6% and 16.6%, respectively. The prevalence of moderate and severe anxiety was 24.7% and 22.7%, respectively. Age, gender, economic level, having contact with COVID-19 patients, and following COVID-19 news were independent variables significantly associated with stress levels. Age, gender, economic level, employment status, having symptoms of COVID-19, having contact with COVID-19 patients, and following COVID-19 news were independent variables significantly associated with anxiety levels. Conclusion A high proportion of people experienced stress and anxiety during the COVID-19 outbreak in Erbil, Iraqi Kurdistan Region. Females, younger age, poor, and unemployed reported significantly higher stress and anxiety levels. There is a need to establish mechanisms at the population level to decrease the stress and anxiety risks and provide mental health coping measures in times of crisis, such as education about positive thinking, stress management programs, and the role of social support