4,363 research outputs found
Challenges in the Management of Road Safety in Tanzania: The Need for an Integration Framework
Tanzania is hardest hit by daily accident deaths and casualties on the roads. Although various measures have been taken by the government, enforcement agencies and NGOs, accidents and fatalities keep growing at a rate above that of killer diseases like malaria, tuberculosis and HIV. The main causes observed were that road safety has multiple key autonomous stakeholders having different fragmented information systems which are not inter-operable because of being proprietary in nature, thus inhibiting the timely and coordinated sharing of information among them. This paper presents the lessons learned from different stakeholders following a series of workshops and meetings with these key stakeholders to understand the problem from their institutional contexts. Hence, anintegration framework is developed and implemented to facilitate enforcement of road traffic regulations and to enable the different stakeholders cooperate and share information efficiently and with transparency in sustained road safety regulations enforcement. It is envisaged that if the integrated platform is successfully adopted, it can reduce the heavy duplication of efforts and investment in incoherent data systems by individual stakeholders in terms of hardware, consumables and personnel resources. The integrated platform for the road safety management system is in place, however, it needs a policy direction from the government to galvanise the major stakeholders
Cyclin-dependent Kinase 5 (Cdk5)-dependent Phosphorylation of p70 Ribosomal S6 Kinase 1 (S6K) Is Required for Dendritic Spine Morphogenesis.
The maturation and maintenance of dendritic spines depends on neuronal activity and protein synthesis. One potential mechanism involves mammalian target of rapamycin, which promotes protein synthesis through phosphorylation of eIF4E-binding protein and p70 ribosomal S6 kinase 1 (S6K). Upon extracellular stimulation, mammalian target of rapamycin phosphorylates S6K at Thr-389. S6K also undergoes phosphorylation at other sites, including four serine residues in the autoinhibitory domain. Despite extensive biochemical studies, the importance of phosphorylation in the autoinhibitory domain in S6K function remains unresolved, and its role has not been explored in the cellular context. Here we demonstrated that S6K in neuron was phosphorylated at Ser-411 within the autoinhibitory domain by cyclin-dependent kinase 5. Ser-411 phosphorylation was regulated by neuronal activity and brain-derived neurotrophic factor (BDNF). Knockdown of S6K in hippocampal neurons by RNAi led to loss of dendritic spines, an effect that mimics neuronal activity blockade by tetrodotoxin. Notably, coexpression of wild type S6K, but not the phospho-deficient S411A mutant, could rescue the spine defects. These findings reveal the importance of cyclin-dependent kinase 5-mediated phosphorylation of S6K at Ser-411 in spine morphogenesis driven by BDNF and neuronal activity.published_or_final_versio
“I Feel Like It’s One of Those Things that Everyone Feels the Same Way About, No One Wants to Discuss It”: A Qualitative Examination of Female College Students’ Pap Smear Experience
The purpose of this study was to examine female college students’ Pap smear experience and communication with their provider before, during, and after the exam. In fall 2019, 158 female college students completed an online survey with closed and open-ended questions. Open-ended responses from participants reporting a previous Pap smear (n=36) were qualitatively analyzed to generate themes to explain female college students’ Pap smear experience and communication behavior with their provider before, during, and after the exam. The main themes identified included: Uncomfortable, Low Patient Engagement, Provider Support, and Provider Trust. Female college students overwhelmingly reported discomfort around the exam and were unaware of how to communicate with their provider; however, participants reported satisfaction with their care when the provider offered support and guidance. Findings suggest a need to develop strategies to address discomfort and enhance female college students’ communication skills with providers concerning the Pap smear exam
Cosmological Adaptive Mesh Refinement
We describe a grid-based numerical method for 3D hydrodynamic cosmological
simulations which is adaptive in space and time and combines the best features
of higher order--accurate Godunov schemes for Eulerian hydrodynamics with
adaptive particle--mesh methods for collisionless particles. The basis for our
method is the structured adaptive mesh refinement (AMR) algorithm of Berger &
Collela (1989), which we have extended to cosmological hydro + N-body
simulations. The resulting multiscale hybrid method is a powerful alternative
to particle-based methods in current use. The choices we have made in
constructing this algorithm are discussed, and its performance on the Zeldovich
pancake test problem is given. We present a sample application of our method to
the problem of first structure formation. We have achieved a spatial dynamic
range in a 3D multispecies gas + dark matter
calculation, which is sufficient to resolve the formation of primordial
protostellar cloud cores starting from linear matter fluctuations in an
expanding FRW universe.Comment: 14 pages, 3 figures (incl. one large color PS) to appear in
"Numerical Astrophysics 1998", eds. S. Miyama & K. Tomisaka, Tokyo, March
10-13, 199
Effect of Dzyaloshinskii–Moriya interaction on Heisenberg antiferromagnetic spin chain in a longitudinal magnetic field
Using functional integral method for the Heisenberg antiferromagnetic spin chain with the added Dzyaloshinskii-Moriya Interaction in the presence of the longitudinal magnetic field, we find out expression for free energy of the spin chain via spin fluctuations, from which quantities characterize the antiferromagnetic order and phase transition such as staggered and total magnetizations derived. From that, we deduce the significant effect of the Dzyaloshinskii-Moriya interaction on the reduction of the antiferromagnetic order and show that the total magnetization can be deviated from the initial one under the influence of canting of the spins due to a combination of the Dzyaloshinskii-Moriya interaction and the magnetic field. Besides, the remarkable role of the transverse spin fluctuations due to the above factors on the antiferromagnetic behaviours of the spin chain is also indicated.  
Large deviation principle at fixed time in Glauber evolutions
Abstract: We consider the evolution of an asymptotically decoupled probability measure ν on Ising spin configurations under a Glauber dynamics. We prove that for any t > 0, ν t is asymptotically decoupled and hence satisfies a large deviation principle with the relative entropy density as rate function
Strain-induced partially flat band, helical snake states, and interface superconductivity in topological crystalline insulators
Topological crystalline insulators in IV-VI compounds host novel topological
surface states consisting of multi-valley massless Dirac fermions at low
energy. Here we show that strain generically acts as an effective gauge field
on these Dirac fermions and creates pseudo-Landau orbitals without breaking
time-reversal symmetry. We predict the realization of this phenomenon in IV-VI
semiconductor heterostructures, due to a naturally occurring misfit dislocation
array at the interface that produces a periodically varying strain field.
Remarkably, the zero-energy Landau orbitals form a flat band in the vicinity of
the Dirac point, and coexist with a network of snake states at higher energy.
We propose that the high density of states of this flat band gives rise to
interface superconductivity observed in IV-VI semiconductor multilayers at
unusually high temperatures, with non-BCS behavior. Our work demonstrates a new
route to altering macroscopic electronic properties to achieve a partially flat
band, and paves the way for realizing novel correlated states of matter.Comment: Accepted by Nature Physic
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