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Dynamics at the crystal-melt interface in a supercooled chalcogenide liquid near the glass transition.
Direct quantitative measurements of nanoscale dynamical processes associated with structural relaxation and crystallization near the glass transition are a major experimental challenge. These type of processes have been primarily treated as macroscopic phenomena within the framework of phenomenological models and bulk experiments. Here, we report x-ray photon correlation spectroscopy measurements of dynamics at the crystal-melt interface during the radiation induced formation of Se nano-crystallites in pure Se and in binary AsSe4 glass-forming liquids near their glass transition temperature. We observe a heterogeneous dynamical behaviour where the intensity correlation functions g2(q, t) exhibits either a compressed or a stretched exponential decay, depending on the size of the Se nano-crystallites. The corresponding relaxation timescale for the AsSe4 liquid increases as the temperature is raised, which can be attributed to changes in the chemical composition of the melt at the crystal-melt interface with the growth of the Se nano-crystallites
Status of tomato Lycopersicon esculentum Mill.cultivation and pesticide use in Golapar area of Uttarakhand, India
Tomato is one of the most widely grown temperate vegetable crops grown in Himalayas and Tarai region of Northern India. Being the high value crop is important in raising the income of the farmers. However, from past few years, they are facing the problem of numerous diseases in the crop and subsequent yield losses and thusaffecting the economic status of the growers. Present study was carried out with the objective to discern the current status of disease occurrence in tomato and management strategies followed by the growers of Golapar area of District Nainital, a major tomato growing area of Uttarakhand state. Purposive sampling was followed for selection of the area and respondents were selected randomly. Data was collected through structured questionnaire. It was found that tomato is the key vegetable in the area and preference of the varieties was largely based on the marketable yield, larger fruit size, higher market price and also depends on the availability of seed with the local distributer. Average loss ranges from 20-80% due to late blight, leaf curl, early blight, wilt and stem rot diseases. Application of pesticides was exceedingly high as number of pesticide sprays was varied in the range of 10-40. However, disease management varied from 5-60% depending on the chemical application by the farmers. This study will be supportive to manipulate adopted strategies to reduce the losses and low cost proven technologies can be introduced for disease management for the benefit of the farmers
Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5-10 GHz frequency range
We present a scanning transmission x-ray microscopy setup combined with a
novel microwave synchronization scheme in order to study high frequency
magnetization dynamics at synchrotron light sources. The sensitivity necessary
to detect small changes of the magnetization on short time scales and nanometer
spatial dimensions is achieved by combination of the developed excitation
mechanism with a single photon counting electronics that is locked to the
synchrotron operation frequency. The required mechanical stability is achieved
by a compact design of the microscope. Our instrument is capable of creating
direct images of dynamical phenomena in the 5-10 GHz range, with 35 nm
resolution. When used together with circularly polarized x-rays, the above
capabilities can be combined to study magnetic phenomena at microwave
frequencies, such as ferromagnetic resonance (FMR) and spin waves. We
demonstrate the capabilities of our technique by presenting phase resolved
images of a 6 GHz nanoscale spin wave generated by a spin torque oscillator, as
well as the uniform ferromagnetic precession with ~0.1 deg amplitude at 9 GHz
in a micrometer-sized cobalt strip.Comment: 9 pages, 7 figure
Mycotoxin management through transformations – A review
Mycotoxins are toxic secondary metabolic products of various fungi, mainly belonging to the genera Fusarium (Trichothecenes, Zearalenone), Aspergillus (Aflatoxin) and Penicillium (Ochratoxin) and can be found in almost 25% of the world’s agricultural commodities. These compounds are toxic to humans, animals and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. It has been estimated that at least 300 of these fungal metabolites are potentially toxic to animals and humans. In India 50% losses of agricultural commodities are due to postharvest losses. A number of physical and chemical approaches have already been taken to reduce the effect of mycotoxins, but due to certain limitations of physical and chemical strategies prompted search for other solutions to the mycotoxin hazards. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. Consequently, a new approach is applied for managing mycotoxins through transformations that offer specific, efficient and eco-friendly way for detoxification of mycotoxins. This review aims to brings about the up-to-date management strategies mainly through transformation (genetic and bio) to pre-vent or reduce post harvest damages to the crops caused by storage fungi and the contamination of food and feed by mycotoxins. It will make aware of the new technologies or management methods for mycotoxins through transformation. The transformation methods may become the technology of choice, as they offer a specific, irreversible, efficient and environment friendly way of detoxification that leaves neither toxic residues nor any undesirable by-products
Mycotoxin management through transformations – A review
Mycotoxins are toxic secondary metabolic products of various fungi, mainly belonging to the genera Fusarium (Trichothecenes, Zearalenone), Aspergillus (Aflatoxin) and Penicillium (Ochratoxin) and can be found in almost 25% of the world’s agricultural commodities. These compounds are toxic to humans, animals and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. It has been estimated that at least 300 of these fungal metabolites are potentially toxic to animals and humans. In India 50% losses of agricultural commodities are due to postharvest losses. A number of physical and chemical approaches have already been taken to reduce the effect of mycotoxins, but due to certain limitations of physical and chemical strategies prompted search for other solutions to the mycotoxin hazards. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. Consequently, a new approach is applied for managing mycotoxins through transformations that offer specific, efficient and eco-friendly way for detoxification of mycotoxins. This review aims to brings about the up-to-date management strategies mainly through transformation (genetic and bio) to pre-vent or reduce post harvest damages to the crops caused by storage fungi and the contamination of food and feed by mycotoxins. It will make aware of the new technologies or management methods for mycotoxins through transformation. The transformation methods may become the technology of choice, as they offer a specific, irreversible, efficient and environment friendly way of detoxification that leaves neither toxic residues nor any undesirable by-products
Effect of Natalizumab Treatment on Circulating Plasmacytoid Dendritic Cells: A Cross-Sectional Observational Study in Patients with Multiple Sclerosis
Objectives: Dendritic cells (DCs) serve a critical role both in promoting and inhibiting adaptive immunity. The goal of this study was to investigate the effect of natalizumab (NTZ) treatment on DC numbers, phenotype, and function in patients with multiple sclerosis (MS). Methods: Frequency and phenotype of myeloid and plasmacytoid DCs (MDCs and PDCs, respectively) were analyzed in blood from two separate cohorts of untreated, interferon-treated, or NTZ-treated MS patients. In addition, PDCs were stimulated with CpG-containing oligonucleotides or co-cultured with homologous T cells in the presence or absence of NTZ in vitro to determine functional effects of NTZ treatment. Results: We observed that NTZ treatment was associated with a 25–50% reduction in PDC frequency in peripheral blood as compared to untreated MS patients, while the frequency of MDCs was unchanged. PDCs in NTZ-treated patients displayed a mature, activated phenotype with increased expression of HLA-DR, TLR9, CCR7, IL-6 and IL-12. In contrast, in vitro treatment with NTZ did not increase markers of PDC activation or their ability to induce T cell differentiation. Conclusion: Our study shows that NTZ treatment is associated with a reduced frequency of PDCs in the peripheral circulation, but that PDCs in NTZ-treated individuals display an activated phenotype. Taken together the data suggests that transmigration of activated PDCs is preferentially affected by blockade of integrin α4 leading to an increased frequency of activated PDCs in blood
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