Two experiments on pregnant cows were carried out. Inactivated strains of Moraxella bovis were used in aerosol or hypodermic vaccine. Cows at 6.5 and 8 months of pregnancy and their calves in 5-6 ...weeks of life were immunized. The high level of the specific anti- Moraxella bovis antibodies in cows and calves was stated. No differences between efficiency of two vaccines were observed
•Quantum-chemical modeling reveals complex electronic structure and electrostatic interaction in PA6-CNT complex.•MWCNT induces significant rearrangement of RS, affecting vibrational structure of ...PA.•PA6-MWCNT nanocomposites exhibit percolation dependence with a threshold of 1.41 vol% MWCNT.
In this work, quantum chemical modeling, electrical conductivity, Raman scattering, and photoluminescence of polyamide 6 nanocomposites with multi-walled carbon nanotubes (0–2.5 vol%) were investigated. It was shown that the concentration dependence of the electrical conductivity obeys the percolation theory and has the value of percolation threshold 1.41 vol%. The conductivity value of the composite at 2.5 vol% nanotubes is 1.1*10-3 S/cm. It was found that in PA6 nanocomposites filled with MWCNT an increase in the concentration of nanotubes from 0.001 to 0.015 vol%, namely in the pre-percolation region of electrical conductivity, due to a significant restructuring of the Raman spectra, which consists in a shift of the vibrational modes of the methylene groups CH2 and amide I, as well as in a change of their relative intensities. From the photoluminescence spectra of PA6-MWCNT, it can be seen, that the carbon nanotubes largely determine the conformational changes in the polymer matrix and have little effect on the defective structure of the polymer itself.
The goal: to establish the mechanisms of electrical conductivity and the interaction of nanotubes with polyamide macromolecules and its influence on the electronic and optical properties of nanocomposites of polyamide multi-walled carbon nanotubes.
Depression and cardiovascular disease are common and associated with one another in HIV disease. This study aimed to determine the frequency and everyday functioning implications of the clinical ...syndrome of vascular depression among people living with HIV (PLWH). Participants in this cross-sectional study included 536 PLWH and 272 seronegative individuals who completed a biomedical and psychiatric research evaluation. Vascular depression was operationalized as the current presence of: 1) two or more vascular conditions; and 2) depression as determined by a normative elevation on the Depression/Dejection subscale of the Profile of Mood States or a diagnosis of Major Depressive Disorder per the Composite International Diagnostic Interview. Everyday functioning was measured by both self- and clinician-rated activities of daily living. A logistic regression model showed that HIV was associated with a three-fold increased risk of vascular depression, independent of potential confounding factors. A second logistic regression model within the PLWH sample showed that PLWH with vascular depression had significantly greater odds of dependence in everyday functioning as compared to PLWH with either vascular disease or depression alone. The elevated frequency of vascular depression in PLWH is consistent with the vascular depression hypothesis from the late-life depression literature. The high rate of functional dependence among PLWH with vascular depression highlights the clinical importance of prospective work on this syndrome in the context of HIV disease.
Quantum-chemical modeling of the geometry of PVC molecules and the calculation of Raman scattering spectra were performed. The calculated spectra are in good agreement with the experimental ones, ...including the extraction of adjacent Cl atoms. The Raman spectra of PVC-MWCNT nanocomposites with various filler content with functionalization during electron irradiation with an absorption dose of 1 Mrad were obtained. It was shown that with the change of MWCNT content in irradiated samples there is a complex rearrangement of the molecular structure of PVC and conjugate sequences due to the influence of nanotubes and irradiation, as well as to the aggregation of MWCNT.
While one can characterize mental health using questionnaires, such tools do not provide direct insight into the underlying biology. By linking approaches that visualize brain activity to ...questionnaires in the context of individualized prediction, we can gain new insights into the biology and behavioral aspects of brain health. Resting-state fMRI (rs-fMRI) can be used to identify biomarkers of these conditions and study patterns of abnormal connectivity. In this work, we estimate mental health quality for individual participants using static functional network connectivity (sFNC) data from rs-fMRI. The deep learning model uses the sFNC data as input to predict four categories of mental health quality and visualize the neural patterns indicative of each group. We used guided gradient class activation maps (guided Grad-CAM) to identify the most discriminative sFNC patterns. The effectiveness of this model was validated using the UK Biobank dataset, in which we showed that our approach outperformed four alternative models by 4-18% accuracy. The proposed model’s performance evaluation yielded a classification accuracy of 76%, 78%, 88%, and 98% for the excellent, good, fair, and poor mental health categories, with poor mental health accuracy being the highest. The findings show distinct sFNC patterns across each group. The patterns associated with excellent mental health consist of the cerebellar-subcortical regions, whereas the most prominent areas in the poor mental health category are in the sensorimotor and visual domains. Thus the combination of rs-fMRI and deep learning opens a promising path for developing a comprehensive framework to evaluate and measure mental health. Moreover, this approach had the potential to guide the development of personalized interventions and enable the monitoring of treatment response. Overall this highlights the crucial role of advanced imaging modalities and deep learning algorithms in advancing our understanding and management of mental health.
Background
Clinicians and researchers utilize neuroimaging (NI) biomarkers of Alzheimer’s disease (AD) at an increasing rate. It is crucial that we determine whether these biomarkers generalize to ...underrepresented populations, particularly Black Americans (BAs), as they are 64% more likely as white individuals to develop AD. BAs may exhibit unique AD biomarker profiles across disease states, including NI biomarkers. Investigating biomarkers in at‐risk individuals may allow for early identification and intervention. Here we analyze comprehensive NI biomarkers including resting state fMRI, white matter lesions, and hippocampal volumes in conjunction with cerebrospinal fluid (CSF) markers in a midlife, racially diverse, cognitively normal cohort with a parental history of AD.
Method
Data included 57 cognitively normal, middle‐aged individuals, 14 BAs and 43 white. CSF was acquired via lumbar puncture to determine CSF t‐tau and Aβ1‐42 concentrations. Using resting state fMRI data, we analyzed default mode network connectivity between the posterior cingulate & precuneus, parrahippocampal gyrus (PHG), temporal pole, hippocampus, and lateral temporal cortex. We obtained regional WMH data from FLAIR images using an in‐house algorithm, and hippocampal volumes from Freesurfer. In our multivariate model, outcome variables were connectivity values, regional WMH and hippocampal volumes, with race and CSF t‐tau and Aβ1‐42 as our independent variables with a race X CSF interaction term.
Result
We identified a significant race X t‐tau and race X Aβ1‐42 interaction term for temporal and parietal WMH volumes and connectivity between PHG and temporal pole. Higher AD CSF biomarkers negatively correlated with brain connectivity (p = 0.01), and positively with WMH volume (p<0.001) in BAs.
Conclusion
We extend our previous work to a middle‐aged cohort to show that DMN connectivity may be a predictor of AD risk in middle‐age, particularly for BAs, and that BAs may exhibit earlier vulnerability to vascular lesions. We support previous work that the temporal lobe is the first region to experience AD‐related connectivity changes, and that WMHs may predispose this region to AD vulnerability. This study emphasizes the need for recruitment of diverse cohorts in NI studies of AD.
Dynamic functional network connectivity (dFNC) is an expansion of traditional, static FNC that measures connectivity variation among brain networks throughout scan duration. We used a large ...resting‐state fMRI (rs‐fMRI) sample from the PREDICT‐HD study (N = 183 Huntington disease gene mutation carriers HDgmc and N = 78 healthy control HC participants) to examine whole‐brain dFNC and its associations with CAG repeat length as well as the product of scaled CAG length and age, a variable representing disease burden. We also tested for relationships between functional connectivity and motor and cognitive measurements. Group independent component analysis was applied to rs‐fMRI data to obtain whole‐brain resting state networks. FNC was defined as the correlation between RSN time‐courses. Dynamic FNC behavior was captured using a sliding time window approach, and FNC results from each window were assigned to four clusters representing FNC states, using a k‐means clustering algorithm. HDgmc individuals spent significantly more time in State‐1 (the state with the weakest FNC pattern) compared to HC. However, overall HC individuals showed more FNC dynamism than HDgmc. Significant associations between FNC states and genetic and clinical variables were also identified. In FNC State‐4 (the one that most resembled static FNC), HDgmc exhibited significantly decreased connectivity between the putamen and medial prefrontal cortex compared to HC, and this was significantly associated with cognitive performance. In FNC State‐1, disease burden in HDgmc participants was significantly associated with connectivity between the postcentral gyrus and posterior cingulate cortex, as well as between the inferior occipital gyrus and posterior parietal cortex.
Background
Alzheimer’s disease (AD) is twice as likely to occur in African Americans than in Non‐Hispanic Whites. However, current neuroimaging models of AD do not accurately overlay onto the African ...American profile of this disease. One variable that could contribute to more accurate modeling is the inclusion of vascular factors into models of AD, as African Americans are more likely to have vascular as well as AD. Functional MRI is a widely used method to measure brain activity in individuals with AD. Connectivity in the form of correlated between regions can be used to determine neurological dysfunction. Fronto‐striatal connectivity, while understudied in AD, has shown to be affected by AD and vascular disease. This study attempts to determine if there are connectivity measures that relate to vascular lesions(White Matter Hyperintensities (WMH)) across the disease spectrum, and whether these relationships are uniform across race.
Method
We analyzed data from 88 people (54= NC, 34=MCI). We conducted functional connectivity using DPARSFA toolbox with connectivity calculated between the following fronto‐striatal regions within each hemisphere: anterior putamen, middle frontal gyrus, superior frontal gyrus (putamen output regions), pre‐ and postcentral gyri (putamen input regions). To calculate regional white matter hyperintensity we used in‐house code to overlay a regional atlas onto a WMH mask extracted from a T2 weighted FLAIR image, and assigned a score to each individual representing load (0=no WMH in any regions, 1=WMH in 1 or the other region, 2=present in both regions.
Result
Across race and diagnostic categories, WMH were related negatively to right anterior putamen connectivity to the pre and post central gyri such that as WMH load increased, connectivity also decreased. This relationship continued for connectivity measures between the right anterior putamen and the superior and middle frontal gyri, but only within African Americans.
Conclusion
Fronto‐striatal connectivity did correlate with regional WMH load in a uniform manner across races for cortical input regions to the putamen, and this relationship extended to Africans Americans within cortical output regions. This relationship was identified across diagnostic categories, and could be useful in studies investigating vascular relationships to AD biomarkers.
Embryological investigations were carried out on developing anthers of Atropa belladonna grown in natural conditions and on anthers which produced androgenic embryos in the in vitro culture. The ...anatomy of developing anthers was analized in details. Meiotic abnormalities were not detected and 36 bivalents were present at metaphase of meiosis I. About 90% of pollen grains were normally developed. Anthers inoculated at the tetrad or microspore stage and cultured on Linsmaier and Skoog medium with kinetin 4 mg/1 and IAA - 2 mg/1 produced androgenic embryos. Differences in the development of septum, in the morphology of pollen grains, formation of tapetum, development of proembryos and the occurrence of storage materials were recorded. The origin of autopoliploid plants from haploid cells is discussed.
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