610 research outputs found
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Post-Earthquake Home Reconstruction in the Surrounding Hills of Kathmandu Valley, Nepal, PRP 200
In April of 2015, a 7.6 magnitude earthquake struck the Kathmandu Valley at the center of Nepal. Within the following year, Kathmandu was struck by a 7.3 magnitude earthquake and multiple aftershocks. The initial earthquake caused the deaths of 8,856 people, injured 22,309, and affected eight million more. Many agencies around the world came together to fund reconstruction efforts as part of a Nepal and a Multi-Donor Trust Fund (MDTF). The MDTF conducted an Earthquake Housing Damage and Characteristics Survey (EHDC) which led to the creation of Nepal Rural Housing Reconstruction Program (NRHRP), which sought to reconstruct earthquake-resistant homes. The NRHRP developed a homeowner-driven grant process and
established the National Reconstruction Authority (NRA) to distribute housing reconstruction grants to families. Those grants were to be paid out via three tranches, each after the completion of a specific construction phase.
During 2017, an international collaborative effort began among four parties: Hiroshima University (HU); Tribhuvan University (TU); Nepal’s Alternative Energy Promotion Center (AEPC); and the Lyndon B. Johnson School of Public Affairs (LBJ) of the University of Texas at Austin (UT). The team investigated the challenges and opportunities for reconstruction of homes in rural areas damaged by the 2015 earthquake in and around the hinterland of Kathmandu Valley, Nepal. Within the context of a university course, students began by studying alternative building technologies (ABTs) being implemented in Nepal by local nongovernmental organizations (NGOs). When project members visited Nepal in March 2017, they interviewed rural residents to identify barriers to home reconstruction. During a field study, the students also met with local governmental officials and NGO representatives.
This report describes students’ field investigation in Nepal, background research on alternative building technologies (ABTs) for home reconstruction, and recommendations developed from consultation with stakeholders and technical advisors. The first chapter starts with the earthquake and its associated damage and describes the response of the Government of Nepal (GON) and the international community in forming the MDTF, the NRHRP, and the NRA. The second chapter discusses different alternative building technologies (ABTs) considered by the GON, including bamboo, hempcrete, rammed earth, Compressed Stabilized Earth Brick (CSEB), earthbags, and modified conventional housing. Each section describes the type of building style,
its construction, materials and labor required, estimates of construction time (if available), costs, and a brief section on comparative advantages and disadvantages.
The third chapter describes the 2017 field study in Nepal, included the locations of the field study and interviews and discussions with local NGOs, the governmental agencies, and local residents. The research group sought to learn whether a lack of affordable and appropriate building methods could explain why many villagers still live in temporary shelters. Village residents discussed barriers to housing reconstruction unrelated to the type of home being built. The final chapter presents conclusions from 2017 field study observations of the three villages. Researchers found four common barriers to reconstruction: the cost of transportation and materials; insufficient reconstruction incentives; grant processes with many procedural barriers to funding; and the need for consistent interaction of the community with governmental agencies. One suggestion is to evaluate the home reconstruction program to assess its procedures and outcomes. A second suggestion is for Nepal to enhance the number and authority of mobile teams of professionals to assist villagers seeking to reconstruct homes.Public Affair
Homeostatic Plasticity and STDP: Keeping a Neuron's Cool in a Fluctuating World
Spike-timing-dependent plasticity (STDP) offers a powerful means of forming and modifying neural circuits. Experimental and theoretical studies have demonstrated its potential usefulness for functions as varied as cortical map development, sharpening of sensory receptive fields, working memory, and associative learning. Even so, it is unlikely that STDP works alone. Unless changes in synaptic strength are coordinated across multiple synapses and with other neuronal properties, it is difficult to maintain the stability and functionality of neural circuits. Moreover, there are certain features of early postnatal development (e.g., rapid changes in sensory input) that threaten neural circuit stability in ways that STDP may not be well placed to counter. These considerations have led researchers to investigate additional types of plasticity, complementary to STDP, that may serve to constrain synaptic weights and/or neuronal firing. These are collectively known as “homeostatic plasticity” and include schemes that control the total synaptic strength of a neuron, that modulate its intrinsic excitability as a function of average activity, or that make the ability of synapses to undergo Hebbian modification depend upon their history of use. In this article, we will review the experimental evidence for homeostatic forms of plasticity and consider how they might interact with STDP during development, and learning and memory
Identification of Ajnala skeletal remains using multiple forensic anthropological methods and techniques: a bioarchaeological report.
Fragmented and badly damaged commingled human remains present a tough challenge for their identification pursuits in forensic anthropology. Thousands of unknown human remains along with items of contextual identity, reportedly belonging to 282 Indian sepoys killed in 1857, were exhumed non-scientifically from a disused ancient well at Ajnala (Amritsar, India). In this manuscript, the non-scientific excavation of unknown human remains from the abandoned well, their forensic anthropological strategies for identification purposes, challenges being faced and future possibilities of their biological profiling have been discussed. Multiple methods and techniques like anthropological examinations, odontological profiling, radiological analyses, stable isotope and mitochondrial DNA (mtDNA) analyses were applied to few bones and teeth collected from the Ajnala skeletal assemblage. Though majority of studied bones and teeth were found belonging to adult males, very few of them had morphological, osteological and molecular features questioning the authenticity and validity of the written records. Due to certain ambiguous findings or gaps observed between the anthropological analyses of the Ajnala skeletal remains and the reported versions about their affiliations; certain advanced radiological, chemical and molecular techniques were applied to estimate their probable age, sex and populational affinity. The obtained radiological, isotopic and molecular signatures of the remains were compared with the available databases to estimate their affinity with the individuals of geographic area to whom the remains reportedly belonged to. The maternally inherited mtDNA haplogroup assignments, and stable isotope analysis of carbon and oxygen suggested that the studied human remains belonged to the individuals from West Bengal, Bihar, Odisha, Awadh (presently in Uttar Pradesh) and parts of Meghalaya and Manipur as potential regions of their geographic identity and thus, attributing the victims to be non-local to the site. However, merely on the basis of forensic anthropological examinations of very few bones and teeth (collected out of a huge collection of thousands of bones and teeth); it would be just an unqualified and sweeping conclusion to claim their identity as adult or non-adult, male or female, local or non-local, victims of 1857 mass killings or to the victims of ceremonial sacrifices or criminal activities committed in the past. A sufficient number of bones and teeth along with items of personal identity needs to be examined with multiple scientific techniques to arrive at some valid conclusions about their biological identity
A NOVEL APPROACH TOWARDS DEVELOPMENT OF QUINAZOLINE DERIVATIVES IN PAIN MANAGEMENT
ABSTRACT- Â Objective: To synthesis evaluation of the analgesic and anti-inflammatory activities of pyrazoline bearing 4(3H)-quinazolinone derivatives. Methods: Synthesis of Chalcone (3a-3j) involves the Claisen-Schmidt condensation of equimolar quantities of substituted acetophenone with aromatic aldehyde in the presence of aqueous alkali (10%). Comp. (3a-3j) undergoes cyloaddition reaction with semicarbazide HCl in the presence of suitable solvent to yield comp. (4a-4j). It undergoes addition cyclization reaction with anthranillic acid to yield final comp. (6a-6j). Acute toxicity study of synthesized compound was found according to OECD guidelines 423. The test compound do not showed any toxicity up to 200mg/kg dose. Mortality was not observed during the course of study. The analgesic and anti-inflammatory activity of all synthesized compounds were carried by using hot plate method and Carrageenan induced Rat Paw Edema Method respectively. Results: All compounds synthesized are obtained in crystalline form with good practical yield. The purity and homogeneity of compounds synthesized were determined by sharp melting points and TLC method. The chemical structures were confirmed by FTIR, 1HNMR, and Mass spectrum. Conclusion: The synthesized compound 6b, 6d, 6e, 6i and 6j showed good analgesic and anti-inflammatory activities whereas others showed significant activities. Keywords: Quinazoline, pyrazole, analgesic and anti-inflammatory activity
Spatially Resolved Galaxy Star Formation and its Environmental Dependence I
We use the photometric information contained in individual pixels of 44,964
(0.019<z<0.125 and -23.5<M_r<-20.5) galaxies in the Fourth Data Release (DR4)
of the Sloan Digital Sky Survey to investigate the effects of environment on
galaxy star formation (SF). We use the pixel-z technique, which combines
stellar population synthesis models with photometric redshift template fitting
on the scale of individual pixels in galaxy images. Spectral energy
distributions are constructed, sampling a wide range of properties such as age,
star formation rate (SFR), dust obscuration and metallicity. By summing the
SFRs in the pixels, we demonstrate that the distribution of total galaxy SFR
shifts to lower values as the local density of surrounding galaxies increases,
as found in other studies. The effect is most prominent in the galaxies with
the highest star formation, and we see the break in the SFR-density relation at
a local galaxy density of (Mpc/h). Since our method
allows us to spatially resolve the SF distribution within galaxies, we can
calculate the mean SFR of each galaxy as a function of radius. We find that on
average the mean SFR is dominated by SF in the central regions of galaxies, and
that the trend for suppression of SFR in high density environments is driven by
a reduction in this nuclear SF. We also find that the mean SFR in the outskirts
is largely independent of environmental effects. This trend in the mean SFR is
shared by galaxies which are highly star forming, while those which are weakly
star forming show no statistically significant correlation between their
environment and the mean SFR at any radius.Comment: 37 pages, 11 figures. Referee's comments included and matches version
accepted for publication in the Astrophysical Journal. For high resolution
figures, see http://www.phyast.pitt.edu/~welikala/pixelz/paper1
Constraint-based Wavevector- and Frequency-dependent Exchange-Correlation Kernel of the Uniform Electron Gas
According to time-dependent density functional theory, the exact
exchange-correlation kernel f(n, q, ) determines not only the
ground-state energy but also the excited-state energies/lifetimes and
time-dependent linear density response of an electron gas of uniform density n
3/(4r). Here we propose a parametrization of this function based
upon the satisfaction of exact constraints. For the static ( = 0)
limit, we modify the model of Constantin and Pitarke at small wavevector q to
recover the known second-order gradient expansion, plus other changes. For all
frequencies at q 0, we use the model of Gross, Kohn, and Iwamoto.
A Cauchy integral extends this model to complex and implies the
standard Kramers-Kronig relations. A scaling relation permits closed forms for
not only the imaginary but also the real part of f for real . We
then combine these ingredients by damping out the dependence at large
q in the same way that the q dependence is damped. Away from q 0 and
0, the correlation contribution to the kernel becomes dominant
over exchange, even at r 4, the valence electron density of metallic
sodium. The resulting correlation energy from integration over imaginary
is essentially exact. The plasmon pole of the density response
function is found by analytic continuation of f to just below
the real axis, and the resulting plasmon lifetime first decreases from infinity
and then increases as q grows from 0 toward the electron-hole continuum. A
static charge-density wave is found for r 69, and shown to be
associated with softening of the plasmon mode. The exchange-only version of our
static kernel confirms Overhauser's 1968 prediction that correlation enhances
the charge-density wave.Comment: 20 pages including 11 figure
Pixel-z: Studying Substructure and Stellar Populations in Galaxies out to z~3 using Pixel Colors I. Systematics
We perform a pixel-by-pixel analysis of 467 galaxies in the GOODS-VIMOS
survey to study systematic effects in extracting properties of stellar
populations (age, dust, metallicity and SFR) from pixel colors using the
pixel-z method. The systematics studied include the effect of the input stellar
population synthesis model, passband limitations and differences between
individual SED fits to pixels and global SED-fitting to a galaxy's colors. We
find that with optical-only colors, the systematic errors due to differences
among the models are well constrained. The largest impact on the age and SFR
e-folding time estimates in the pixels arises from differences between the
Maraston models and the Bruzual&Charlot models, when optical colors are used.
This results in systematic differences larger than the 2{\sigma} uncertainties
in over 10 percent of all pixels in the galaxy sample. The effect of
restricting the available passbands is more severe. In 26 percent of pixels in
the full sample, passband limitations result in systematic biases in the age
estimates which are larger than the 2{\sigma} uncertainties. Systematic effects
from model differences are reexamined using Near-IR colors for a subsample of
46 galaxies in the GOODS-NICMOS survey. For z > 1, the observed optical/NIR
colors span the rest frame UV-optical SED, and the use of different models does
not significantly bias the estimates of the stellar population parameters
compared to using optical-only colors. We then illustrate how pixel-z can be
applied robustly to make detailed studies of substructure in high redshift
galaxies such as (a) radial gradients of age, SFR, sSFR and dust and (b) the
distribution of these properties within subcomponents such as spiral arms and
clumps. Finally, we show preliminary results from the CANDELS survey
illustrating how the new HST/WFC3 data can be exploited to probe substructure
in z~1-3 galaxies.Comment: 37 pages, 21 figures, submitted to Ap
Evolutionary fine-tuning of conformational ensembles in FimH during host-pathogen interactions
Positive selection in the two-domain type 1 pilus adhesin FimH enhances Escherichia coli fitness in urinary tract infection (UTI). We report a comprehensive atomic-level view of FimH in two-state conformational ensembles in solution, composed of one low-affinity tense (T) and multiple high-affinity relaxed (R) conformations. Positively selected residues allosterically modulate the equilibrium between these two conformational states, each of which engages mannose through distinct binding orientations. A FimH variant that only adopts the R state is severely attenuated early in a mouse model of uncomplicated UTI but is proficient at colonizing catheterized bladders in vivo or bladder transitional-like epithelial cells in vitro. Thus, the bladder habitat has barrier(s) to R state–mediated colonization possibly conferred by the terminally differentiated bladder epithelium and/or decoy receptors in urine. Together, our studies reveal the conformational landscape in solution, binding mechanisms, and adhesive strength of an allosteric two-domain adhesin that evolved “moderate” affinity to optimize persistence in the bladder during UTI
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Digital Orthopaedics: A Glimpse Into the Future in the Midst of a Pandemic.
BackgroundThe response to COVID-19 catalyzed the adoption and integration of digital health tools into the health care delivery model for musculoskeletal patients. The change, suspension, or relaxation of Medicare and federal guidelines enabled the rapid implementation of these technologies. The expansion of payment models for virtual care facilitated its rapid adoption. The authors aim to provide several examples of digital health solutions utilized to manage orthopedic patients during the pandemic and discuss what features of these technologies are likely to continue to provide value to patients and clinicians following its resolution.ConclusionThe widespread adoption of new technologies enabling providers to care for patients remotely has the potential to permanently change the expectations of all stakeholders about the way care is provided in orthopedics. The new era of Digital Orthopaedics will see a gradual and nondisruptive integration of technologies that support the patient's journey through the successful management of their musculoskeletal disease
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