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Perinatal aspects on the covid-19 pandemic: a practical resource for perinatal-neonatal specialists.
BackgroundLittle is known about the perinatal aspects of COVID-19.ObjectiveTo summarize available evidence and provide perinatologists/neonatologists with tools for managing their patients.MethodsAnalysis of available literature on COVID-19 using Medline and Google scholar.ResultsFrom scant data: vertical transmission from maternal infection during the third trimester probably does not occur or likely it occurs very rarely. Consequences of COVID-19 infection among women during early pregnancy remain unknown. We cannot conclude if pregnancy is a risk factor for more severe disease in women with COVID-19. Little is known about disease severity in neonates, and from very few samples, the presence of SARS-CoV-2 has not been documented in human milk. Links to websites of organizations with updated COVID-19 information are provided. Infographics summarize an approach to the pregnant woman or neonate with suspected or confirmed COVID-19.ConclusionsAs the pandemic continues, more data will be available that could lead to changes in current knowledge and recommendations
Content-Centric Networking at Internet Scale through The Integration of Name Resolution and Routing
We introduce CCN-RAMP (Routing to Anchors Matching Prefixes), a new approach
to content-centric networking. CCN-RAMP offers all the advantages of the Named
Data Networking (NDN) and Content-Centric Networking (CCNx) but eliminates the
need to either use Pending Interest Tables (PIT) or lookup large Forwarding
Information Bases (FIB) listing name prefixes in order to forward Interests.
CCN-RAMP uses small forwarding tables listing anonymous sources of Interests
and the locations of name prefixes. Such tables are immune to Interest-flooding
attacks and are smaller than the FIBs used to list IP address ranges in the
Internet. We show that no forwarding loops can occur with CCN-RAMP, and that
Interests flow over the same routes that NDN and CCNx would maintain using
large FIBs. The results of simulation experiments comparing NDN with CCN-RAMP
based on ndnSIM show that CCN-RAMP requires forwarding state that is orders of
magnitude smaller than what NDN requires, and attains even better performance
Magnetic phase diagram of the antiferromagnetic pyrochlore Gd2Ti2O7
Gd2Ti2O7 is a highly frustrated antiferromagnet on a pyrochlore lattice,
where apart from the Heisenberg exchange the spins also interact via
dipole-dipole forces. We report on low-temperature specific heat measurements
performed on single crystals of Gd2Ti2O7 for three different directions of an
applied magnetic field. The measurements reveal the strongly anisotropic
behaviour of Gd2Ti2O7 in a magnetic field despite the apparent absence of a
significant single-ion anisotropy for Gd3+. The H-T phase diagrams are
constructed for H//111], H//[110] and H//[112]. The results indicate that
further theoretical work beyond a simple mean-field model is required.Comment: 4 figure
Simple smoothness indicator WENO-Z scheme for hyperbolic conservation laws
The advantage of WENO-JS5 scheme [ J. Comput. Phys. 1996] over the WENO-LOC
scheme [J. Comput. Phys.1994] is that the WENO-LOC nonlinear weights do not
achieve the desired order of convergence in smooth monotone regions and at
critical points. In this article, this drawback is achieved with the WENO-LOC
smoothness indicators by constructing a WENO-Z type nonlinear weights which
contains a novel global smoothness indicator. This novel smoothness indicator
measures the derivatives of the reconstructed flux in a global stencil, as a
result, the proposed numerical scheme could decrease the dissipation near the
discontinuous regions. The theoretical and numerical experiments to achieve the
required order of convergence in smooth monotone regions, at critical points,
the essentially non-oscillatory (ENO), the analysis of parameters involved in
the nonlinear weights like and are studied. From this study, we
conclude that the imposition of certain conditions on and , the
proposed scheme achieves the global order of accuracy in the presence of an
arbitrary number of critical points. Numerical tests for scalar, one and
two-dimensional system of Euler equations are presented to show the effective
performance of the proposed numerical scheme.Comment: 25 pages, 10 figure
Counting Giant Gravitons in AdS_3
We quantize the set of all quarter BPS brane probe solutions in global AdS_3
\times S^3 \times T^4/K3 found in arxiv:0709.1168 [hep-th]. We show that,
generically, these solutions give rise to states in discrete representations of
the SL(2,R) WZW model on AdS_3. Our procedure provides us with a detailed
description of the low energy 1/4 and 1/2 BPS sectors of string theory on this
background. The 1/4 BPS partition function jumps as we move off the point in
moduli space where the bulk theta angle and NS-NS fields vanish. We show that
generic 1/2 BPS states are protected because they correspond to geodesics
rather than puffed up branes. By exactly quantizing the simplest of the probes
above, we verify our description of 1/4 BPS states and find agreement with the
known spectrum of 1/2 BPS states of the boundary theory. We also consider the
contribution of these probes to the elliptic genus and discuss puzzles, and
their possible resolutions, in reproducing the elliptic genus of the symmetric
product.Comment: 47 pages; (v2) references and minor clarifications adde
Fish culture in marine farm at Mandapam
The large-scale monoculture and polyculture of the milkfish, Chanos chanos were reported earlier form Southeast Asian countries.This article highlights some interesting and encouraging results obtained during the experiments of milkfish monoculture and polyculture of milkfish with mullet in Mandapam ponds. In the monoculture of milkfish the average size of the fish as well as the production rate could be substantially stepped up by resorting to supplementary feeding. In the polyculture of milkfish, the average growth rate was found to be more or less similar in both the fertilized and unfertilized ponds but the survival and production rates were higher in unfertilized pond. The yield of milkfish under monoculture in the present study is comparable to that of Ceylon, where selective harvesting followed by replenishment gave a production of 799 to 1159 kg/ha/annum. A production rate of 1405 kg/ha/10 months obtained in the present experimental polyculture of milkfish
Finfish resources around Andaman and Nicobar islands
The average catch rate of finfishes obtained by FORV Sagar Sampada from the
survey area in the Andaman Sea was 259 kg/hr and the yield ranged from 8.6 to 1260
kg/hr. Silver bellies was the most abundant component (37.5%) with a catch rate of
96.9 kg/hr. Carangids, elasmobranchs and perches accounted for 20.3%, 11.9% and
8.0% of the total catch and the corresponding catch rates were 52.5, 31.1 and 20.8
kg/hr respectively. The highest catch rate of 1260 kg/hr was recorded from 13°10'N
- 92°37'E at a depth of 65m. The catch rate indicated that the depth zone 51-100 m
is productive and yielded 84.7% of the total catch at a catch rate of 501.4 kg/hr.
Although the pelagic trawl was operated at 38 stations, the catch realised was
neghgible (0.83 kg/hr)
Experiencing space–time: the stretched lifeworlds of migrant workers in India
In the relatively rare instances when the spatialities of temporary migrant work, workers’ journeys, and labour-market negotiations have been the subject of scholarly attention, there has been little work that integrates time into the analysis. Building on a case study of low-paid and insecure migrant manual workers in the context of rapid economic growth in India, we examine both material and subjective dimensions of these workers’ spatiotemporal experiences. What does it mean to live life stretched out, multiplyattached to places across national space? What kinds of place attachments emerge for people temporarily sojourning in, rather than moving to, new places to reside and work? Our analysis of the spatiotemporalities of migrant workers’ experiences in India suggests that, over time, this group of workers use their own agency to seek to avoid the experience of humiliation and indignity in employment relations. Like David Harvey, we argue that money needs to be integrated into such analysis, along with space and time. The paper sheds light on processes of exclusion, inequality and diff erentiation, unequal power geometries, and social topographies that contrast with neoliberalist narratives of ‘Indian shining
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