2,520 research outputs found
Ground-based salt seeding in Tamil nadu state, south India, 1973-1977
A long series of ground-based salt seeding experiments in north India during the southwest monsoonseasons (June-September) of 1957-66 showed significant increases of about 20 percent in rainfall on seeded days (Ramana Murty and Biswas, 1968). In September of 1974, salt seeding from aircraft on isolated maritime warm cumulus clouds within 50 km off the coast at Bombay(18 15’N, 72v 49’D, II m ASL) was followed by increases in radar echo area coverage in the vertical and in echo intensity (Chatterjee et al., 1978). seek similar results in a different area, a randomized salt-seeding experiment, using a single ground-based generator, was conducted in 1973 and 1975-77 just west of Madras, on the Bengal coast 1,000 km southeast of Bombay. There in the state of Tamil Nadu, South India, the main rainy season is during the northeast monsoon(Oct-Dec), whereas in most parts of India, about 75 percent of the annual rainfall is received during the southwest monsoon(Ananthakrishnan, 1977
Healthcare workers’ beliefs, motivations and behaviours affecting adequate provision of sexual and reproductive healthcare services to adolescents in Cape Town, South Africa: a qualitative study
BACKGROUND: Adolescents’ sexual and reproductive healthcare (SRH) needs have been prioritized globally, and they
have the rights to access and utilize SRH services for their needs. However, adolescents under-utilize SRH services,
especially in sub-Saharan Africa. Many factors play a role in the under-utilization of SRH services by adolescents,
such as the attitude and behaviour of healthcare workers. The aim of this study therefore, was to explore and gain
an in-depth understanding of healthcare workers’ beliefs, motivations and behaviours affecting adequate provision
of these services to adolescents in South Africa.
METHODS: Twenty-four healthcare workers in public SRH services in Cape Town, South Africa participated in this
qualitative study through focus group discussions. To fulfill the aims of this study, nine focus group discussions
were conducted among the SRH nurses.
RESULTS: SRH nurses indicated that they are experiencing challenges with the concept and practice of termination
of pregnancy. They explained that this practice contradicted their opposing beliefs and values. Some nurses felt
that they had insufficient SRH skills, which hinder their provision of adequate SRH services to adolescents, while
others described constraints within the health system such as not enough time to provide the necessary care. They
also explained having limited access to schools where they can provide SRH education and pregnancy prevention
services in the surrounding area.
CONCLUSIONS: Nurses are faced with numerous challenges when providing SRH services to adolescents. Providing
the nurses with training programmes that emphasize value clarification may help them to separate their personal
beliefs and norms from the workplace practice. This may help them to focus on the needs of the adolescent in a
way that is beneficial to them. At the health systems level, issues such as clinic operating hours need to be structured
such that the time pressure and constraints upon the nurse is relieved
Spatio-temporal Models of Lymphangiogenesis in Wound Healing
Several studies suggest that one possible cause of impaired wound healing is
failed or insufficient lymphangiogenesis, that is the formation of new
lymphatic capillaries. Although many mathematical models have been developed to
describe the formation of blood capillaries (angiogenesis), very few have been
proposed for the regeneration of the lymphatic network. Lymphangiogenesis is a
markedly different process from angiogenesis, occurring at different times and
in response to different chemical stimuli. Two main hypotheses have been
proposed: 1) lymphatic capillaries sprout from existing interrupted ones at the
edge of the wound in analogy to the blood angiogenesis case; 2) lymphatic
endothelial cells first pool in the wound region following the lymph flow and
then, once sufficiently populated, start to form a network. Here we present two
PDE models describing lymphangiogenesis according to these two different
hypotheses. Further, we include the effect of advection due to interstitial
flow and lymph flow coming from open capillaries. The variables represent
different cell densities and growth factor concentrations, and where possible
the parameters are estimated from biological data. The models are then solved
numerically and the results are compared with the available biological
literature.Comment: 29 pages, 9 Figures, 6 Tables (39 figure files in total
Early star-forming galaxies and the reionization of the Universe
Star forming galaxies represent a valuable tracer of cosmic history. Recent
observational progress with Hubble Space Telescope has led to the discovery and
study of the earliest-known galaxies corresponding to a period when the
Universe was only ~800 million years old. Intense ultraviolet radiation from
these early galaxies probably induced a major event in cosmic history: the
reionization of intergalactic hydrogen. New techniques are being developed to
understand the properties of these most distant galaxies and determine their
influence on the evolution of the universe.Comment: Review article appearing in Nature. This posting reflects a submitted
version of the review formatted by the authors, in accordance with Nature
publication policies. For the official, published version of the review,
please see http://www.nature.com/nature/archive/index.htm
Primary intraosseous mucoepidermoid carcinoma of the maxilla
Primary intraosseous mucoepidermoid carcinoma (PIOC) is an infrequent malignancy of the head and neck that exhibits diverse biological behavior. The rareness of the location for a salivary gland tumor and the clinical and radiographic manifestations, suggestive of an odontogenic lesion often pose a diagnostic challenge. We hereby report such a unique case of central mucoepidermoid carcinoma that presented in an ambiguous manner, developing in the maxilla and intruding into the adjacent vital structures, adding a literature review.Keywords: Mucoepidermoid carcinoma, salivary gland malignancy, maxilla, CT imaging,histopathologic pictur
Long-term coding of personal and universal associations underlying the memory web in the human brain
Neurons in the medial temporal lobe (MTL), a critical area for declarative memory, have been shown to change their tuning in associative learning tasks. Yet, it is unclear how durable these neuronal representations are and if they outlast the execution of the task. To address this issue, we studied the responses of MTL neurons in neurosurgical patients to known concepts (people and places). Using association scores provided by the patients and a web-based metric, here we show that whenever MTL neurons respond to more than one concept, these concepts are typically related. Furthermore, the degree of association between concepts could be successfully predicted based on the neurons’ response patterns. These results provide evidence for a long-term involvement of MTL neurons in the representation of durable associations, a hallmark of human declarative memory
Tigers of Sundarbans in India: Is the Population a Separate Conservation Unit?
The Sundarbans tiger inhabits a unique mangrove habitat and are morphologically distinct from the recognized tiger subspecies in terms of skull morphometrics and body size. Thus, there is an urgent need to assess their ecological and genetic distinctiveness and determine if Sundarbans tigers should be defined and managed as separate conservation unit. We utilized nine microsatellites and 3 kb from four mitochondrial DNA (mtDNA) genes to estimate genetic variability, population structure, demographic parameters and visualize historic and contemporary connectivity among tiger populations from Sundarbans and mainland India. We also evaluated the traits that determine exchangeability or adaptive differences among tiger populations. Data from both markers suggest that Sundarbans tiger is not a separate tiger subspecies and should be regarded as Bengal tiger (P. t. tigris) subspecies. Maximum likelihood phylogenetic analyses of the mtDNA data revealed reciprocal monophyly. Genetic differentiation was found stronger for mtDNA than nuclear DNA. Microsatellite markers indicated low genetic variation in Sundarbans tigers (He= 0.58) as compared to other mainland populations, such as northern and Peninsular (Hebetween 0.67- 0.70). Molecular data supports migration between mainland and Sundarbans populations until very recent times. We attribute this reduction in gene flow to accelerated fragmentation and habitat alteration in the landscape over the past few centuries. Demographic analyses suggest that Sundarbans tigers have diverged recently from peninsular tiger population within last 2000 years. Sundarbans tigers are the most divergent group of Bengal tigers, and ecologically non-exchangeable with other tiger populations, and thus should be managed as a separate "evolutionarily significant unit" (ESU) following the adaptive evolutionary conservation (AEC) concept.Wildlife Institute of India, Dehra Dun (India)
Recommended from our members
PS18kh: A New Tidal Disruption Event with a Non-axisymmetric Accretion Disk
We present the discovery of PS18kh, a tidal disruption event discovered at the center of SDSS J075654.53+341543.6 (d ≃ 322 Mpc) by the Pan-STARRS Survey for Transients. Our data set includes pre-discovery survey data from Pan-STARRS, the All-sky Automated Survey for Supernovae, and the Asteroid Terrestrial-impact Last Alert System as well as high-cadence, multiwavelength follow-up data from ground-based telescopes and Swift, spanning from 56 days before peak light until 75 days after. The optical/UV emission from PS18kh is well-fit as a blackbody with temperatures ranging from T ≃ 12,000 K to T ≃ 25,000 K and it peaked at a luminosity of L ≃ 8.8 × 10 erg s . PS18kh radiated E = (3.45 ± 0.22) × 10 erg over the period of observation, with (1.42 ± 0.20) × 10 erg being released during the rise to peak. Spectra of PS18kh show a changing, boxy/double-peaked Hα emission feature, which becomes more prominent over time. We use models of non-axisymmetric accretion disks to describe the profile of the Hα line and its evolution. We find that at early times the high accretion rate leads the disk to emit a wind which modifies the shape of the line profile and makes it bell-shaped. At late times, the wind becomes optically thin, allowing the non-axisymmetric perturbations to show up in the line profile. The line-emitting portion of the disk extends from r ∼ 60r to an outer radius of r ∼ 1400r and the perturbations can be represented either as an eccentricity in the outer rings of the disk or as a spiral arm in the inner disk. 43 -1 50 50 in g out
Lipidomic analysis of plasma samples from women with polycystic ovary syndrome
Abstract Polycystic ovary syndrome (PCOS) is a common disorder affecting between 5 and 18 % of females of reproductive age and can be diagnosed based on a combination of clinical, ultrasound and biochemical features, none of which on its own is diagnostic. A lipidomic approach using liquid chromatography coupled with accurate mass high-resolution mass-spectrometry (LCHRMS) was used to investigate if there were any differences in plasma lipidomic profiles in women with PCOS compared with control women at different stages of menstrual cycle. Plasma samples from 40 women with PCOS and 40 controls aged between 18 and 40 years were analysed in combination with multivariate statistical analyses. Multivariate data analysis (LASSO regression and OPLSDA) of the sample lipidomics datasets showed a weak prediction model for PCOS versus control samples from the follicular and mid-cycle phases of the menstrual cycle, but a stronger model (specificity 85 % and sensitivity 95 %) for PCOS versus the luteal phase menstrual cycle controls. The PCOS vs luteal phase model showed increased levels of plasma triglycerides and sphingomyelins and decreased levels of lysophosphatidylcholines and phosphatidylethanolamines in PCOS women compared with controls. Lipid biomarkers of PCOS were tentatively identified which may be useful in distinguishing PCOS from controls especially when performed during the menstrual cycle luteal phase
Comparison of glottic views and intubation times in the supine and 25 degree back-up positions
Background: We explored whether positioning patients in a 25° back-up sniffing position improved glottic views
and ease of intubation.
Methods: In the first part of the study, patients were intubated in the standard supine sniffing position. In the
second part, the back of the operating table was raised 25° from the horizontal by flexion of the torso at the hips
while maintaining the sniffing position. The best view obtained during laryngoscopy was assessed using the
Cormack and Lehane classification and Percentage of Glottic Opening (POGO) score. The number of attempts at
both laryngoscopy and tracheal intubation, together with the use of ancillary equipment and manoeuvres were
recorded. The ease of intubation was indirectly assessed by recording the time interval between beginning of
laryngoscopy and insertion of the tracheal tube.
Results: Seven hundred eighty one unselected surgical patients scheduled for non-emergency surgery were
included. In the back-up position, ancillary laryngeal manoeuvres, which included cricoid pressure, backwards
upwards rightward pressure and external laryngeal manipulation, were required less frequently (19.6 % versus 24.
6 %, p = 0.004). The time from beginning of laryngoscopy to insertion of the tracheal tube was 14 % shorter
(median time 24 versus 28 s, p = 0.031) in the back-up position. There was no significant difference in glottic views.
Conclusions: The 25° back-up position improved the ease of intubation as judged by the need for fewer ancillary
manoeuvres and shorter time for intubation.
Trial registration: ClinicalTrials.gov Identifier: NCT02934347 registered retrospectively on 14th Oct 2016
- …
