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This study examined the hypothesis that xanthosine (XS) treatment would promote mammary-specific gene expression and stem cell transcripts and have a positive influence on milk yield of dairy goats. Seven primiparous Beetal goats were assigned to the study. Five days after kidding, one gland (either left or right) was infused with XS (TRT) twice daily for 3 d and the other gland with no XS infusion served as a control (CON). Mammary biopsies were collected at 10 d and RNA was isolated. Gene expression analysis of milk synthesis genes, mammary stem/progenitor cell markers, cell proliferation and differentiation markers were performed using real time quantitative PCR (RT-qPCR). Results showed that the transcripts of milk synthesis genes (BLG4, CSN2, LALBA, FABP3, CD36) and mammary stem/progenitor cell markers (ALDH1 and NR5A2) were increased in as a result of XS treatment. Average milk yield in TRT glands was increased marginally (approximately ~2% P = 0·05, paired t-test) per gland relative to CON gland until 7 wk. After 7 wk, milk yield of TRT and CON glands did not differ. Analysis of milk composition revealed that protein, lactose, fat and solids-not-fat percentages remained the same in TRT and CON glands. These results suggest that XS increases expression of milk synthesis genes, mammary stem/progenitor cells and has a small effect on milk yield.
In search of a suitable resource conservation technology under pigeonpea (Cajanus cajan L.)–wheat (Triticum aestivum L.) system in the Indo-Gangetic Plains, the effects of conservation agriculture (CA) on crop productivity and water-use efficiency (WUE) were evaluated during a 3-year study. The treatments were: conventional tillage (CT), zero tillage (ZT) with planting on permanent narrow beds (PNB), PNB with residue (PNB + R), ZT with planting on permanent broad beds (PBB) and PBB + R. The PBB + R plots had higher pigeonpea grain yield than the CT plots in all 3 years. However, wheat grain yields under all plots were similar in all years except for PBB + R plots in the second year, which had higher wheat yield than CT plots. The contrast analysis showed that pigeonpea grain yield of CA plots was significantly higher than CT plots in the first year. However, both pigeonpea and wheat grain yields during the last 2 years under CA and CT plots were similar. The PBB + R plots had higher system WUE than the CT plots in the second and third years. Plots under CA had significantly higher WUE and significantly lower water use than CT plots in these years. The PBB + R plots had higher WUE than PNB + R and PNB plots. Also, the PBB plots had higher WUE than PNB in the second and third years, despite similar water use. The interactions of bed width and residue management for all parameters in the second and third years were not significant. Those positive impacts under PBB + R plots over CT plots were perceived to be due to no tillage and significantly higher amount of estimated residue retention. Thus, both PBB and PBB + R technologies would be very useful under a pigeonpea–wheat cropping system in this region.
In this paper, the design analysis of a multi-way and high-power radial combiner is presented. This combiner incorporates a rigid stripline-type combining structure. This analysis, based on an equivalent circuit model and segmentation of the radial transmission line, provides simple design formulae. The developed methodology, after fine-tuning with the help of an electromagnetic full-wave simulator, is physically demonstrated by developing a high-power (16 kW average) and high combining-efficiency (98.9%) 16-way combiner at the center frequency of 505.8 MHz. Its efficient and repeatable performance, fabrication-friendly structure, and absence of the heat-related problem, caused by the isolation resistor, are the main features of this design.
We have presented the observations of O VI absorption at 1032 Å towards 22 sightlines in 10 superbubbles (SBs) of the Large Magellanic Cloud (LMC) using the data obtained from the Far Ultraviolet Spectroscopic Explorer (FUSE). The estimated abundance of O VI in the SBs varies from a minimum of (1.09 ±0.22)×1014 atoms/cm2 in SB N206 to a maximum of (3.71±0.23)×1014 atoms/cm2 in SB N70. We find about a 46% excess in the abundance of O VI in the SBs compared to the non-SB lines of sight. Even inside a SB, O VI column density (N(O VI)) varies by about a factor of 2 to 2.5. These data are useful in understanding the nature of the hot gas in SBs.
Radio frequency (RF) and microwave amplifier research has been largely focused on solid-state technology in recent years. This paper presents design and performance characterization of a 50-kW modular solid-state amplifier, operating at 505.8 MHz. It includes architecture selection and design procedures based on circuit and EM simulations for its building blocks like solid-state amplifier modules, combiners, dividers, and directional couplers. Key performance objectives such as efficiency, return loss, and amplitude/phase imbalance are discussed for this amplifier for real-time operation. This amplifier is serving as the state-of-the-art RF source in Indus-2 synchrotron radiation source. Characterization on component level as well as system level of this amplifier serves useful data for RF designers working in communication and particle accelerator fields.
Thin films of InSb with different thickness (t = 5, 10 and 15 kÅ) were
deposited on to glass substrate by flash evaporation technique. The
structural and electrical properties were investigated and the effect of
films thickness on films properties was discussed. XRD analysis of the films
as a function of film thickness revealed that crystallinity improves with
film thickness. Temperature dependence of the Hall parameters were studied
in a wide range, 20 < T < 300 K. The temperature variation of the Hall
coefficient and conductivity shows an activated nature with negative
temperature coefficient confirming that the prepared films of InSb are
semiconducting in nature with n-type conductivity. Size effect was observed
as the defect density is much smaller for thicker films and as a result
electrical conductivity of the films increases with increasing film
thickness with the increase of the charge carriers through the film. An
increase in mobility with sample thickness has been observed. The mobility
variations with temperature revealed a transition from lattice to impurity
scattering in the observed temperature range.
Residual water vapour present in the vacuum system has been observed to play a dominant oxidising role in the 250 keV D+ induced radiolysis of polyimide (Kapton-H). The partial pressure (pp) of water in the vacuum system decreases sharply as the D+ beam impinges the polymeric surface, but soon after, it recovers to its initial value as the accumulated dose increases. Emission of CO2 is observed which has its maximum at a time when the H2O partial pressure is at a minimum. The CO2 level also returns to its original level with time. This complementary variation of CO2 and H2O confirms that absorbed and adsorbed water molecules are radiolysed by the ion beam and initiate oxidation of the radiolytically evolved CO to yield CO2 on and within the ion implanted surface of the polyimide. Further, the small enhancement in the 28 amu peak (N2 + CO), which exhibits no maximum/minimum over the entire implantation time, can be understood in terms of the evolution of N2 from the imide ring as a result of radiolysis of this nitrogen containing polymers.
In this paper an attempt was made to impose different degrees of rapid solidification by spraying on diverse substrates of varying thermal properties. Substrates such as Copper, Aluminum, Stainless steel, Low alloy steel substrates were used to alter the imposed cooling rate and thereby the amount of residual α phase. A start powder of 3 wt % Alumina-titania powder was used for spraying to a thickness of 250 μm on the different substrates specified. In all cases the rapidly solidified phases show nanocrystalline sizes with the most rapidly solidified metastable γ phase showing finer grain size of less than 25 nm. The surface roughness of the substrate and the coating were characterized by Atomic force microscopy. In contrary to the Alumina-13 wt % titania, coupons of Alumina-3 wt % titania had shown poor indentation fracture toughness with increased amount of residual α phase. Coupons of stainless steel and low alloy steel had shown the lowest fracture toughness when tested by Vickers type indentation at loads of 3 N and 5 N. In contrast to these results the interfacial toughness when measured by Rockwell indentation technique at loads of 150 N was found to be dependent on the elastic modulus of the substrate more than the coating hardness. The interfacial toughness was found to be lower for softer material such as aluminum and copper than stainless steel and low alloy steel.
Multi quantum wells of InGaAs/InP grown by metal organic chemical vapor deposition have been irradiated using swift heavy ions. Irradiation has been performed using 150MeV Ag and 200MeV Au ions. Both as-grown and irradiated samples were subjected to rapid thermal annealing at 500 and 7000C for 60s. As-grown, irradiated and annealed samples were subjected to high resolution x-ray diffraction studies. Both symmetric and asymmetric scans were analyzed. The as-grown and Ag ion irradiated samples show sharp and highly ordered satellite peaks whereas, the Au ion irradiated samples show broad and low intense peaks. The higher order satellite peaks of the annealed samples vanished with increase of annealing temperature from 500 to 7000C, indicating mixing induced interfacial disorder. Annealing of irradiated samples show higher mixing and disorder and no higher order satellite peaks were observed. Negligible strain was observed after high temperature annealing of as grown samples. Strain values calculated from the X-ray studies indicate that the irradiated samples have higher strain which has been reduced upon annealing. This indicates that the annealing induced mixing occurs maintaining the lattice parameter close to that of the substrate. The effect of electronic energy loss for interface mixing has been discussed in detail. The role of incident ion fluence in combination with the electronic energy loss will also be discussed in detail. The results have been compared with the literature and discussed in detail.
High fluences of low energy Ge+ ions were implanted into Si matrix. We have also deposited Ge and SiO2 composite films by using the Atom beam sputtering (ABS). The as implanted/as-deposited films were irradiated by Swift Heavy Ions (SHI) with various energies and fluences. These pristine and irradiated samples were subsequently characterized by XRD and Raman to understand the crystallization behavior. Raman studies of the films indicate the formation of Ge crystallites as a result of SHI irradiation. Glancing angle X-ray diffraction results also confirm the presence of Ge crystallites in the irradiated samples. Moreover, the crystalline nature of Ge improves with an increase in fluence. Rutherford back scattering was used to quantify the concentration of Ge in SiO2 matrix and the film thickness. These detailed results have been discussed and compared with the ones available in literature. The basic mechanism for crystallization induced by SHI in these films will be presented.
Epitaxial AlGaN/GaN layers grown by MBE on SiC substrates were irradiated with 150 MeV Ag ions at a fluence of 5×1012 ions/cm2. AlGaN/GaN MQWs were grown on Sapphire substrate by MOCVD and irradiated with 200 MeV Au8+ ions at a fluence of 5×1011 ions/cm2 . These samples were used to study the effects of SHI on optical properties of AlGaN/GaN based nano structures. RBS/Channelling strain measurements were carried out at off normal axis of irradiated and unirradiated samples. In as grown samples, AlGaN layer is partially relaxed with a small compressive strain. After irradiation this compressive strain increases by 0.22% in AlGaN layer. Incident ion energy dependence of dechannelling parameter shows E1/2 dependence, which corresponds to the dislocations. Defect densities were calculated from the E1/2 graph. As a result of irradiation defect density increased on both GaN and AlGaN layer. Optical properties of AlGaN/GaN MQWs before and after irradiation have been analyzed using PL. This study shows that SHI increase the confinement effects in the MQWs and intensity of the active layer of the MQWs luminescence is increased by one order. This may be due to the induced strain in GaN and AlGaN layers. Some unwanted yellow luminescence has also been introduced by the SHI possibly due the point defects or defect luminescence from the induced dislocations in GaN bulk epitaxial layers. In this study, we present some new results concerning high energy irradiation on AlGaN/GaN heterostructures and MQWs characterized by RBS/Channelling and PL.
The electronic transport properties of p-type tin selenide (SnSe)
grown by direct vapor transport (DVT) technique were investigated via Hall
effect in the temperature range 40 <T< 300 K. The temperature
dependence of conductivity revealed the existence of impurity energy level
in the band gap of the crystal. The temperature dependence of the carrier
concentration was analyzed using the single-donor – single-acceptor model.
The Hall mobility increases by decreasing temperature up to 120 K and then
decreases along with temperature. The observed temperature dependant
mobility in the temperature range 120 <T< 300 K and 40 <T< 120 K
was found to be limited by homopolar and ionized impurity mode scatterings
The characteristics of heterojunction diode pSe-nMoSe2
fabricated from thermally evaporated p-Se films on n-type Molybdenum
diselenide (MoSe2) grown by direct vapour transport (DVT) technique
have been examined by using current-voltage measurements. To investigate the
dark current transport mechanism in pSe-nMoSe2 heterojunctions the
current-voltage characteristics were measured in the temperature range
100–300 K. The prepared diode shows a rectification ratio of the order of
103 within the range –2 to 2 V. A multi-step tunnelling model was used
to analyze the I-V-T characteristics of the prepared device. The activation
energy determined from the saturation current was about 1.16 eV.
Understanding seasonal changes in age-related incidence of infections can be revealing for disentangling how host heterogeneities affect transmission and how to control the spread of infections between social groups. Seasonal forcing has been well documented in human childhood diseases but the mechanisms responsible for age-related transmission in free-living and socially structured animal populations are still poorly known. Here we studied the seasonal dynamics of Bordetella bronchiseptica in a free-living rabbit population over 5 years and discuss the possible mechanisms of infection. This bacterium has been isolated in livestock and wildlife where it causes respiratory infections that rapidly spread between individuals and persist as subclinical infections. Sera were collected from rabbits sampled monthly and examined using an ELISA. Findings revealed that B. bronchiseptica circulates in the rabbit population with annual prevalence ranging between 88% and 97%. Both seroprevalence and antibody optical density index exhibited 1-year cycles, indicating that disease outbreaks were seasonal and suggesting that long-lasting antibody protection was transient. Intra-annual dynamics showed a strong seasonal signature associated with the recruitment of naive offspring during the breeding period. Infection appeared to be mainly driven by mother-to-litter contacts rather than by interactions with other members of the community. By age 2 months, 65% of the kittens were seropositive.
This paper examines the trends in utilization of five indicators of reproductive and child health services, namely, childhood immunization, medical assistance at delivery, antenatal care, contraceptive use and unmet need for contraception, by wealth index of the household in India and two disparate states, Uttar Pradesh and Maharashtra. The data from three rounds of the National Family and Health Survey conducted during 1992–2005 are analysed. The wealth index is computed using principal component derived weights from a set of consumer durables, land size, housing quality and water and sanitation facilities of the household, and classified into quintiles for all three rounds. Bivariate analyses, rich–poor ratio and concentration index are used to understand the trends in utilization of, and inequality in, reproductive and child health services. The results indicate huge disparities in utilization of these services, largely to the disadvantage of the poor. Utilization of basic childhood immunization among the poorest and the poor stagnated in India, as well as in both states, during 1998–2005 compared with 1992–1998. The use of maternal care services such as medical assistance at delivery and antenatal care remained at a low level among the poor over this period. However, contraceptive use increased relatively faster among the poor, even with higher unmet need. Of all these services, the inequality in medical assistance at delivery is consistently large, while that of contraceptive use is small. The state-level differences in service coverage by wealth quintiles over time are large.
The continuous wavelet transform is studied on certain Gel'fand–Shilov spaces of type S. It is shown that, for wavelets belonging to the one type of S-space defined on R, the wavelet transform is a continuous linear map of the other type of the S-space into a space of the same type (latter type) defined on R × R+. The wavelet transforms of certain ultradifferentiable functions are also investigated.
A novel microwave-assisted combustion method was used to prepare Ni powder. The method involves the combustion reaction of nickel nitrate and urea as a fuel in the microwave field. The initiation of the exothermic peak of the combustion reaction was found to vary as a function of urea content. The microwave-prepared Ni powder was characterized using x-ray diffraction (XRD), scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, thermogravimetric (TG) analysis, differential thermal analysis (DTA), and magnetic measurement. The XRD pattern revealed that the Ni powder crystallizes with the cubic phase when the molar ratio of fuel to nitrate is varied between 5:1 and 6:1. Above or below that molar ratio, NiO phase coexists as an impurity along with the Ni phase. The magnetization value of Ni measured at room temperature is 53.5 Am2/kg, which is close to the value observed for commercial Ni powder (55.0 Am2/kg). The mechanism for the formation of the Ni and NiO phase is discussed based on the infrared, TG, and DTA data. The method shows that highly pure Ni powder can be prepared using urea as a fuel and microwaves as a source of energy via the solution combustion method.