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Trait-specific characterization of rice landraces has significant potential for germplasm management, varietal identification and mining of novel gene/allele for various traits. In the current study, we have characterized 98 unique rice landraces collected from coastal regions of India, affected by submergence and salinity, based on Sub1 and Saltol quantitative trait loci (QTL) linked microsatellite markers. Among these genotypes, four genotypes (IC536558, IC536559, IC536604 and IC536604-1) collected from Kerala and two genotypes (AC34902 and IC324589) collected from West Bengal were identified with tolerance to submergence and salinity stress. A high level of genetic diversity of He = 0.349 and 0.529 at Sub1 and Saltol QTL region was detected by QTL-linked microsatellite markers, respectively. At Sub1 region one genotype, AC34902, was detected with maximum allelic similarity with FR13A, a known submergence tolerant variety. Besides, five genotypes (IC211188-1, IC536604-1, IC536604, IC536558 and IC536559) showed comparatively close genetic relationship with the salt tolerant variety FL478 for Saltol QTL and were clustered together in the neighbour joining dendrogram. Considering the haplotype structure, five genotypes (IC203801, IC203778, IC324584, IC413608 and IC413638) were identified which did not contain any common allele similar to FR13A but were still tolerant to submergence. These individuals need further characterization for identification of new alleles responsible for their tolerance.
The Square Kilometre Array will be an amazing instrument for pulsar astronomy. While the full SKA will be sensitive enough to detect all pulsars in the Galaxy visible from Earth, already with SKA1, pulsar searches will discover enough pulsars to increase the currently known population by a factor of four, no doubt including a range of amazing unknown sources. Real time processing is needed to deal with the 60 PB of pulsar search data collected per day, using a signal processing pipeline required to perform more than 10 POps. Here we present the suggested design of the pulsar search engine for the SKA and discuss challenges and solutions to the pulsar search venture.
While sharply different rotational temperature for the lower and higher rotational states of H2 have been observed in astrophysical situations, studies on heavier molecules are less encountered. We report here results of plasma spectroscopic studies on the nitrogen system where the FNS bands (0,0) and (0,1) show much distinctive ‘two-temperature’ phenomena, the departure from the high rotational temperature part (840 ± 50°K and 920 ± 30°K respectively) being perceptible at N' (N' + 1) ≅ 160. the experimental system is an electron beam sustained magnetoplasma at 5 × 10−3 torr, with kTe ≅ 1.5 eV and ne ≅ 4 × 1010 cm−3 obtained from in situ measurements of plasma parameters. Relative excitation-deexcitation rates of the N2+ B2Σu+ rotational states and also in relation to those of H2 are discussed.
Hα + [NII] and red continuum CCD images as well as high resolution aperture synthesis CO maps were obtained in order to study the optical jet of the barred spiral galaxy NGC 4258. The CO observations show two clouds near the center of the galaxy; these clouds outline a channel and the Hα jet follows this channel. The observations are consistent with the jet being in or making a small angle with the galaxy plane. It is concluded that the interstellar medium may play an important role in making jets detectable optically and in shaping their forms.
Poaching with snares has been identified as the main cause of decline of the endemic roan antelope Hippotragus equinuslangheldi in Ruma National Park, Kenya, from > 200 in 1979 to 37 in 2009. However, the spatial snaring patterns in the Park are not clearly understood. The focus of our study was to map the spatial distribution of snares in the Park and to identify the factors influencing this distribution, to develop effective methods of wildlife protection. Using data collected from 56 sample plots during 2006–2008, coupled with geographical information system techniques, we investigated the association between the occurrence of snares and the distribution of geographical features (slope, elevation), infrastructure (roads, fences), essential resources for wildlife (water, salt licks, forage), roan locations and wildlife density. Ripley's L function for assessing complete spatial randomness indicated that snares occurred in clumps (hotspots) up to 4 km apart. Negative binomial regression indicated that these hotspots occurred (1) near water resources, salt licks and the Park boundary, (2) far from roan locations and Park roads, (3) in areas with low gradients and low wildlife density, and (4) in areas with burned vegetation. We recommend concentrating routine security patrol efforts and resources on snare hotspots to reduce snaring and to protect the roan antelope and other threatened wildlife.
Nagaland is one of the eight states in the north-eastern region of India, where a considerable diversity exists in cultivated rice. Recent exploration in this tribal-dominated state has resulted in a collection of 130 rice accessions growing under diverse agroecological conditions. The agromorphological characterization data of 124 rice landraces revealed a significant variability in plant architecture and grain morphological and quality traits. Multivariate analyses including principal component analysis (PCA) and cluster analysis were performed to assess the patterns of morphological variation. The PCA extracted 12 components, which explained 75.4% of the total variation for 38 quantitative and qualitative traits. The cluster analysis grouped 124 rice landraces into five clusters, and the number of landraces in each cluster ranged from 1 to 59. The correlations among the traits are discussed, which will be useful in considering traits for genetic improvement in grain yield and quality. The landraces have been conserved in the national genebank for further utilization.
The conflict between wild elephants and rural farmers is of great concern for wildlife management and rural development in most parts of Asia and Africa. In Sri Lanka, the conflict is at a very acute stage, as revealed by the fact that between 1992 and 2001 a total of 536 people were killed by wild elephants and that elephant mortality has reached a level of more than three elephant losses per week. Habitat destruction caused by illegal human encroachments and settlements, interruption of elephant corridors and scarcity of food and water in the national parks are some of the causes that have led to the increase of the human–elephant conflicts (HEC) in all wildlife regions in Sri Lanka. Rapid economic development in the dry zone of the country led to large-scale deforestation. In addition, the civil war further increased the conflict by forcing elephants to shift from forests and national parks in the north and east to the south and the west. As their habitats are increasingly lost, wild elephants often have no other choice than invading nearby farm fields causing damage to crops, trees, storage, houses and other properties, sometimes also resulting in the loss of human lives. In response, farm households are compelled to retaliate in various ways to protect their crops, including the killing of elephants. As stated by Heffernan (2005), the factors driving HECs are complex and case specific to environmental and social variables. The intensity of the HEC depends on elephant-related parameters such as aggressiveness to post-traumatic stress disorder or propensity to feed on field crops instead of the more difficult to find forest plants. Thus, HECs are created in the interaction between the forest environment and people’s actions such as encroachment and land claims.
Elephant are the largest terrestrial animal on earth and they require approximately 130–300 kg of feed and 100–200 l of water per day (WWF 2002). As their natural habitats become fragmented, elephants move from one forest patch to the other for food and water, travelling about 20–25 km per day. In Asian countries, including Bangladesh, Bhutan, China, Cambodia, India, Indonesia, Laos, Myanmar, Malaysia, Nepal, Sri Lanka, Thailand and Vietnam, elephants are restricted to a few isolated and fragmented populations, a total number of approximately 35 000–50 000 elephants thus being affected by rapid population growth (Santiapillai and Jackson 1990, Sukumar 1989). In fact, 70% of elephant habitats in Asia were lost between 1960–2000 (Wickramasinghe and Santiapillai 2000).
We present here the latest results from experimental studies aiming at measuring the Mass
Absorption Coefficient (MAC) of interstellar silicate dust analogues at low temperatures
in the far infrared and submillimetre domains which are necessary for the analysis of
astronomical data. These results show that above 100 μm, the MAC of
amorphous silicate nano-grains has a complex dependence with the grain temperature and
with the wavelength. This has to be considered when interpreting astronomical observations
to avoid errors on the derived parameters such as the dust mass and its physical and
A buffalo oocyte-specific subtracted cDNA library was constructed to identify exclusively or preferentially oocyte-expressed genes. The library represented an enriched population of transcripts obtained from oocytes of diverse ovarian follicular origin and at different stages of in vitro maturation. A total of 1173 high-quality sequences of oocyte-specific genes were clustered into 645 unique sequences, out of which 65.76% were represented as singlets and 34.26% as contig expressed sequence tags (ESTs; clusters). Analysis of sequences revealed that 498 of these sequences were identified as a known sequence in mammalian species including buffalo, 103 as uncharacterized ESTs and 44 unknown sequences including 1 novel EST, so far not reported in any species. Gene ontology annotation classified these sequences into functional categories of cellular events and biological processes associated with oocyte competence. Expression status of the isolated unknown ESTs confirmed that many of these are expressed in oocytes exclusively and in others preferentially, some in excess of 80-fold greater in comparison with a variety of somatic tissues. The isolated novel EST was detected to be expressed exclusively in oocytes and testicular cells only. To our knowledge, this is the first report giving a detailed transcriptome account of oocyte-expressed genes in buffalo. This study will provide important information on the physiological control of oocyte development, as well as many questions yet to be addressed on the reproductive process of buffalo.
We have modified Sb2Te3 thin film thermoelectric materials by scanning a femtosecond laser across the film surface to create track-like nanostructures. These nanotracks have widths of 50-80 nm and a periodicity of ∼ 130 nm. We show that the nanotrack morphology is highly dependent on laser fluence and scan speed. Moreover, we performed transient thermoreflectance measurements on a laser-irradiated film and found a thermal conductivity reduction of 4.5% in the nanostructured regions compared to that of the unmodified regions. These results suggest the potential use of femtosecond pulsed lasers to create nanostructured thermoelectric materials with improved performance.
Background: The Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery (CERAD-NAB) offers information on the clinical diagnosis of Alzheimer's disease (AD) and gives a profile of cognitive functioning. This study explores the effects of age, education and gender on participants' performance on eight subtests in the Chinese-Cantonese version of the CERAD-NAB.
Methods: The original English version of the CERAD-NAB was translated and content-validated into a Chinese-Cantonese version to suit the Hong Kong Chinese population. The battery was administered to 187 healthy volunteers aged 60 to 94 years. Participants were excluded if they had neurological, medical or psychiatric disorders (including dementia). Stepwise multiple linear regression analyses were performed to assess the relative contribution of the demographic variables to the scores on each subtest.
Results: The Cantonese version of CERAD-NAB was shown to have good content validity and excellent inter-rater reliability. Stepwise multiple regression analyses revealed that performances on seven and four out of eight subtests in the CERAD-NAB were significantly influenced by education level and age, respectively. Age and education had significant effects on participants' performance on many tests. Gender also showed a significant effect on one subtest.
Conclusions: The preliminary data will serve as an initial phase for clinical interpretation of the CERAD-NAB for Cantonese-speaking Chinese elders.
This work describes an elegant way to control suicide integrity and the quality of the silicide/polySi or amorphous (α) Si interface by a multilayered deposition process. Structurally superior polySi/or-Si layer resulting from this process allows one to reduce the stack height of the polySi/α-Si layer without compromising suicide integrity and silicide/Si interfacial qualities.
Impact of layering during polySi/α-Si deposition on the suicided structure were evaluated from XRD, RBS, cross-sectional TEM, sheet resistance, and SIMS analysis.
Substrate temperature during film growth is an important processing parameter for vapor deposited films of the high Tc superconductors. In this paper we describe a novel, non-contact optical thermometry technique in which the temperature of a transparent substrate or “temperature sensor” is determined from its thermal expansion and refractive index change measured by laser interferometry. The technique is easy to implement and extremely accurate. Temperatures measured with this technique are reported for MgO substrates in varying degrees of thermal contact with a heated backing plate and compared to those measured conventionally by optical pyrometry or thermocouples in close proximity to the sample. The effect of the deposited film on the temperature of radiatively heated substrates will also be discussed.
This paper discusses two analytical techniques: (i) a high resolution transmission electron microscopy (TEM) technique of imaging Si (111) planes at Si/SiO2 interface, and (ii) an accurate measurement of the stress in silicon (Σsi) just below the interface using x-ray microdiffraction (XRMD) technique. The combination of these two techniques allows us to probe Si/SiO2 interfaces for various oxides (75-250Å) grown by different oxidation processes.
The properties of thin films prepared by coevaporation of Y, Cu and Ba.F2, followed by post anneals in O2/H2O, are described. In particular, we emphasize what is known about. the relationship between the processing variables and the physical and chemical structure of the resulting films.
The microstructure of tungsten films deposited by ion-assisted evaporation (IAE) has been examined by transmission electron microscopy. It is proposed that grain shape is strongly associated with stress and texture changes in IAE films. Evidence is also found of stress induced damage in the substrate due to stress transfer from the deposited tungsten films.