746 research outputs found
Recommended from our members
First Do No Harm With COVID-19: Corona Collateral Damage Syndrome
Language matters and communication has consequences, sometimes unforseen. During the Covid-19 public health emergency, public health and elected leaders messaged "Stay at Home" to encourage social distancing to reduce viral transmission. The message in combination with a widespread public fear of acquiring Covid-19 at hospital emergency rooms, resulted in a steep decline in ER visits, even for time sensitive conditions. The Corona Collateral Damage Syndrome is described. A public health messaging course correction is suggested to encourage people with emergencies to come to the emergency room for care
Nanorotors and self-assembling macromolecular machines: The torque ring of the bacterial flagellar motor
The bacterial flagellar motor (BFM) is a self-assembling rotary nanomachine. It converts a flux of cations into the mechanical rotation of long filaments that propel bacteria through viscous media. The BFM contains a torque-generating ring that is complete with molecular machinery known as the switch complex that allows it to reverse directions. With four billion years of optimization, the BFM probably offers the pinnacle of sophisticated nanorotor design. Moreover as one of the best-characterized large biomolecular complexes, it offers the potential for convergence between nanotechnology and biology, which requires an atomic level understanding of BFM structure and function. This review focuses on current molecular models of the reversible BFM and the strategies used to derive them
Essential trauma management training: addressing service delivery needs in active conflict zones in eastern Myanmar
<p>Abstract</p> <p>Introduction</p> <p>Access to governmental and international nongovernmental sources of health care within eastern Myanmar's conflict regions is virtually nonexistent. Historically, under these circumstances effective care for the victims of trauma, particularly landmine injuries, has been severely deficient. Recognizing this, community-based organizations (CBOs) providing health care in these regions sought to scale up the capacity of indigenous health workers to provide trauma care.</p> <p>Case description</p> <p>The Trauma Management Program (TMP) was developed by CBOs in cooperation with a United States-based health care NGO. The goal of the TMP is to improve the capacity of local health workers to deliver effective trauma care. From 2000 to the present, international and local health care educators have conducted regular workshops to train indigenous health workers in the management of landmine injuries, penetrating and blunt trauma, shock, wound and infection care, and orthopedics. Health workers have been regularly resupplied with the surgical instruments, supplies and medications needed to provide the care learnt through TMP training workshops.</p> <p>Discussion and Evaluation</p> <p>Since 2000, approximately 300 health workers have received training through the TMP, as part of a CBO-run health system providing care for approximately 250 000 internally displaced persons (IDPs) and war-affected residents. Based on interviews with health workers, trauma registry inputs and photo/video documentation, protocols and procedures taught during training workshops have been implemented effectively in the field. Between June 2005 and June 2007, more than 200 patients were recorded in the trauma patient registry. The majority were victims of weapons-related trauma.</p> <p>Conclusion</p> <p>This report illustrates a method to increase the capacity of indigenous health workers to manage traumatic injuries. These health workers are able to provide trauma care for otherwise inaccessible populations in remote and conflicted regions. The principles learnt during the implementation of the TMP might be applied in similar settings.</p
Quantum and classical vibrational relaxation dynamics of N-methylacetamide on ab initio potential energy surfaces
Employing extensive quantum-chemical calculations at the DFT/B3LYP and MP2
level, a quartic force field of isolated N-methylacetamide is constructed.
Taking into account 24 vibrational degrees of freedom, the model is employed to
perform numerically exact vibrational configuration interaction calculations of
the vibrational energy relaxation of the amide I mode. It is found that the
energy transfer pathways may sensitively depend on details of the theoretical
description. Moreover, the exact reference calculations were used to study the
applicability and accuracy of (i) the quasiclassical trajectory method, (ii)
time-dependent second-order perturbation theory, and (iii) the instantaneous
normal mode description of frequency fluctuations. Based on the results,
several strategies to describe vibrational energy relaxation in biomolecular
systems are discussed.Comment: 18 pages, 6 figures, submitted to J. Phys. Chem.
The quantum critical point in CeRhIn_5: a resistivity study
The pressure--temperature phase diagram of CeRhIn_5 has been studied under
high magnetic field by resistivity measurements. Clear signatures of a quantum
critical point has been found at a critical pressure of p_c = 2.5 GPa. The
field induced magnetic state in the superconducting state is stable up to the
highest field. At p_c the antiferromagnetic ground-state under high magnetic
field collapses very rapidly. Clear signatures of p_c are the strong
enhancement of the resistivity in the normal state and of the inelastic
scattering term. No clear T2 temperature dependence could be found for
pressures above T_c. From the analysis of the upper critical field within a
strong coupling model we present the pressure dependence of the coupling
parameter lambda and the gyromagnetic ratio g. No signatures of a spatially
modulated order parameter could be evidenced. A detailed comparison with the
magnetic field--temperature phase diagram of CeCoIn_5 is given. The comparison
between CeRhIn_5 and CeCoIn_5 points out the importance to take into account
the field dependence of the effective mass in the calculation of the
superconducting upper critical field H_c2. It suggests also that when the
magnetic critical field H_(0) becomes lower than H_c2 (0)$, the persistence of
a superconducting pseudo-gap may stick the antiferromagnetism to H_c2 (0).Comment: 15 pages, 20 figures, to be published in J. Phys. Soc. Jp
Event-by-Event Fluctuations of Particle Ratios in Central Pb+Pb Collisions at 20 to 158 AGeV
In the vicinity of the QCD phase transition, critical fluctuations have been
predicted to lead to non-statistical fluctuations of particle ratios, depending
on the nature of the phase transition. Recent results of the NA49 energy scan
program show a sharp maximum of the ratio of K+ to Pi+ yields in central Pb+Pb
collisions at beam energies of 20-30 AGeV. This observation has been
interpreted as an indication of a phase transition at low SPS energies. We
present first results on event-by-event fluctuations of the kaon to pion and
proton to pion ratios at beam energies close to this maximum.Comment: 4 pages, 4 figures, Quark Matter 2004 proceeding
Multiplicity fluctuations in nuclear collisions at 158 A GeV
System size dependence of multiplicity fluctuations of charged particles
produced in nuclear collisions at 158 A GeV was studied in the NA49 CERN
experiment. Results indicate a non-monotonic dependence of the scaled variance
of the multiplicity distribution with a maximum for semi-peripheral Pb+Pb
interactions with number of projectile participants of about 35. This effect is
not observed in a string-hadronic model of nuclear collision HIJING.Comment: Presented at "Focus on Multiplicity", 17-19 of June, Bari, Ital
System size and centrality dependence of the balance function in A+A collisions at sqrt[sNN]=17.2 GeV
Electric charge correlations were studied for p+p, C+C, Si+Si, and centrality selected Pb+Pb collisions at sqrt[sNN]=17.2 GeV with the NA49 large acceptance detector at the CERN SPS. In particular, long-range pseudorapidity correlations of oppositely charged particles were measured using the balance function method. The width of the balance function decreases with increasing system size and centrality of the reactions. This decrease could be related to an increasing delay of hadronization in central Pb+Pb collisions
Antiferromagnetism and Superconductivity in Cerium based Heavy Fermion Compounds
The study of competing ground states is a central issue in condensed matter
physic. In this article we will discuss the interplay of antiferromagnetic
order and unconventional superconductivity in Ce based heavy-fermion compounds.
In all discussed examples superconductivity appears at the border of magnetic
order. Special focus is given on the pressure-temperature-magnetic field phase
diagram of CeRhIn5 and CeCoIn5 which allows to discuss microscopic coexistence
of magnetic order and superconductivity in detail. A striking point is the
similarity of the phase diagram of different classes of strongly correlated
systems which is discussed briefly. The recently discovered non-centrosymmetric
superconductors will open a new access with the possible mixing of odd and even
parity pairing.Comment: 38 pages, 22 figures, to be published in Comptes rendues - Physiqu
- …