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Where do women birth during a pandemic? Changing perspectives on Safe Motherhood during the COVID-19 pandemic
During the coronavirus disease 2019 (COVID-19) pandemic, health systems all over the world are either stressed to their maximum capacity or anticipating becoming overwhelmed. The population is advised not to attend hospital unless strictly necessary, yet this advice seems to apply to all but healthy women during childbirth.
Specialized hospital care during childbirth can be lifesaving in case of obstetric complications or for COVID-19 symptomatic women, while strong evidence suggests the appropriateness of midwifery units that are integrated into the healthcare system for eligible women. We must ask ourselves whether obstetric units are the appropriate birthing facilities for healthy women during the pandemic.
We have learned from previous crises that the needs of women and children are often badly served during disasters. The COVID-19 pandemic raises concerns over escalation of mistreatment and abuse media are already reporting on restrictions to the rights of birthing women in Europe and the US. In addition, concerns have emerged over increased risk of infection to COVID-19 among birthing women and familied by concentrating all women in obstetric units and lack of optimal care due to pressure on staff and resources. Women's rights in childbirth are being threatened by lack of care during labor, restrictions on accompaniment, unnecessary interventions including inductions, separation of mother and baby and prohibition on breastfeeding.
An effective response to the crisis depends on strong and coordinated health care systems where mothers can birth safely, and the needs of the newborn babies are met. The interpretation of what constitute safe care is a stimulus for a strong debate between those who argue for strengthening community and primary care services and those who recommend for centralization of all births in hospitals. This debate is particularly salient during this pandemic and in preparation of future pandemics.
We propose a strategic response in the face of the pandemic by expanding the use of midwifery units both alongside the obstetric unit and freestanding (in the community). Where midwifery units are absent pop-up units can be created quickly following the example of the Netherlands. This strategy in high income countries is evidence-based and also serves as a response to the surge in requests of safe childbirths pathways away from the obstetric unit by concerned women at unprecedented rates. We urge policy makers to consider replicating this model in low- and middle-income countries where hospital conditions are more precarious.
A strong collaboration between midwives, nurses, obstetricians and neonatologists and the integration of primary care and acute services could ensure safety while maximizing the rational use of resources. Immediate strategic action would ensure that women are able to access appropriate care at the appropriate time, while hospitals continue to respond to the COVID-19 crisis and obstetric units are kept for women needing specialist care
Continuum discretized BCS approach for weakly bound nuclei
The Bardeen-Cooper-Schrieffer (BCS) formalism is extended by including the
single-particle continuum in order to analyse the evolution of pairing in an
isotopic chain from stability up to the drip line. We propose a continuum
discretized generalized BCS based on single-particle pseudostates (PS). These
PS are generated from the diagonalization of the single-particle Hamiltonian
within a Transformed Harmonic Oscillator (THO) basis. The consistency of the
results versus the size of the basis is studied. The method is applied to
neutron rich Oxygen and Carbon isotopes and compared with similar previous
works and available experimental data. We make use of the flexibility of the
proposed model in order to study the evolution of the occupation of the
low-energy continuum when the system becomes weakly bound. We find a larger
influence of the non-resonant continuum as long as the Fermi level approaches
zero.Comment: 20 pages, 16 figures, to be submitte
Cell adhesion on ti surface with controlled roughness
In this report, the in situ interaction between Saos-2 osteoblast cells and a smooth Ti surface was examined over time. The adhesion kinetics and mechanisms of cellular proliferation were monitored by quartz crystal microbalance (QCM) and electrochemical impedance spectroscopy (EIS). The rate of Saos-2 attachment on Ti surfaces, obtained from the measurements performed with the QCM, is a first-order reaction, with k=2.103 min1. The impedance measurements indicate that in the absence of cells, the Ti resistance diminishes over time (7 days), due to the presence of amino acids and proteins from the culture medium that have been a dsorbed, while in the presence of osteoblasts, this decrease is much greater because of the compounds generated by the cells that accelerate the dissolution of TiAdhesión de osteoblastos sobre una superficie de Ti de rugosidad controlada. En este trabajo, se ha estudiado la interacción in situ entre células osteoblásticas Saos-2 y una superficie de Ti de rugosidad controlada a lo largo del tiempo. El estudio de la cinética y los mecanismos de proliferación celular de adhesión se ha realizado a través de la microbalanza de cristal de cuarzo (QCM) y espectroscopía de impedancia electroquímica (EIS). La velocidad de adhesión de los osteoblastos sobre la superficie de Ti obtenida a través de medidas con la QCM, sigue una reacción de primer orden, con k=2×10−3 min−1. Los ensayos de impedancia indican que, en ausencia de las células, la resistencia del Ti disminuye con el tiempo (7 días), debido a la presencia de aminoácidosy proteínas del medio de cultivo que se han adsorbido, mientras que en presencia de células, esta disminución es mucho mayor debido a los productos metabólicos generados por las células que aceleran la disolución del TiThe authors thank the financial support under projects MAT 2008-06719-C03-01, CTQ2008-05775/ BQU and by the Comunidad Autónoma de Madrid (CAM) through AVANSENS S2009/PPQ-164
On the Ehrenfest theorem of quantum mechanics
We give a mathematically rigorous derivation of Ehrenfest's equations for the
evolution of position and momentum expectation values, under general and
natural assumptions which include atomic and molecular Hamiltonians with
Coulomb interactions.Comment: To appear in J. Math. Phy
Static critical behavior of the ferromagnetic transition in LaMnO3.14 manganite
The ferromagnetic phase transition in LaMnO3.14 is investigated by measuring
the dc magnetization as a function of magnetic field and temperature. Modified
Arrott plot and Kouvel Fisher analysis yield estimates for the critical
exponents beta, and gama, with values between that predicted for the Heisenberg
model and mean field theory. At low fields we found an anomalous small value of
beta, indicating that the critical behavior is influenced by the range of
magnetic fields used.Comment: Presented at ICM 2000 conference. Accepted for publication at J.
Magn. Magn. Mate
Adaptive optics near-IR imaging of NGC2992 - unveiling core structures related to radio figure-8 loops
We present near-IR adaptive optics, VLA radio and HST optical imaging of the
nearby Seyfert galaxy NGC2992. Spiral structure and an extension to the West
are traced down to the core region at the limiting resolution of our near-IR
images. A faint, diffuse loop of near-IR and radio emission is also observed to
the north, embedded within the prominent 2 arcsec radio loop previously
observed to the northwest. Near-IR color maps, and CO narrowband imaging, are
then used to identify which regions may not be purely reddened stellar
populations. Our new data provide evidence that the VLA radio-loop morphology
in the shape of a figure-8 represents two components superimposed: 1) outflow
bubbles out of the plane of the disk, coincident with the extended emission
line region (EELR); 2) star formation along the spiral arm within the galaxy
disk and through the dust lane. The near-IR continuum emission associated with
the outflowing radio bubbles suggest that the radio loops are driven by the
active nucleus.Comment: 10 pages, 9 figures, accepted in MNRA
Ehrenfest dynamics is purity non-preserving: a necessary ingredient for decoherence
We discuss the evolution of purity in mixed quantum/classical approaches to
electronic nonadiabatic dynamics in the context of the Ehrenfest model. As it
is impossible to exactly determine initial conditions for a realistic system,
we choose to work in the statistical Ehrenfest formalism that we introduced in
Ref. 1. From it, we develop a new framework to determine exactly the change in
the purity of the quantum subsystem along the evolution of a statistical
Ehrenfest system. In a simple case, we verify how and to which extent Ehrenfest
statistical dynamics makes a system with more than one classical trajectory and
an initial quantum pure state become a quantum mixed one. We prove this
numerically showing how the evolution of purity depends on time, on the
dimension of the quantum state space , and on the number of classical
trajectories of the initial distribution. The results in this work open new
perspectives for studying decoherence with Ehrenfest dynamics.Comment: Revtex 4-1, 14 pages, 2 figures. Final published versio
Hybrid Access Techniques for Densely Populated Wireless Local Area Networks
Postprint (published version
Searching for Trans Ethyl Methyl Ether in Orion KL
We report on the tentative detection of Ethyl Methyl Ether (tEME),
, through the identification of a large number of rotational
lines from each one of the spin states of the molecule towards Orion KL. We
also search for --n-propanol, , an isomer
of tEME in the same source. We have identified lines of both species in the
IRAM 30m line survey and in the ALMA Science Verification data. We have
obtained ALMA maps to establish the spatial distribution of these species.
Whereas tEME mainly arises from the compact ridge component of Orion,
Gt-n-propanol appears at the emission peak of ethanol (south hot core). The
derived column densities of these species at the location of their emission
peaks are and
for tEME and Gt-n-propanol,
respectively. The rotational temperature is for both molecules. We
also provide maps of , , , , and
to compare the distribution of these organic saturated O-bearing
species containing methyl and ethyl groups in this region. Abundance ratios of
related species and upper limits to the abundances of non-detected ethers are
provided. We derive an abundance ratio in the
compact ridge of Orion.Comment: Accepted in A&A Letter
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