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Differential detection of impact site versus rotational site injury by magnetic resonance imaging and microglial morphology in an unrestrained mild closed head injury model.
Seventy-five percent of all traumatic brain injuries are mild and do not cause readily visible abnormalities on routine medical imaging making it difficult to predict which individuals will develop unwanted clinical sequelae. Microglia are brain-resident macrophages and early responders to brain insults. Their activation is associated with changes in morphology or expression of phenotypic markers including P2Y12 and major histocompatibility complex class II. Using a murine model of unrestrained mild closed head injury (mCHI), we used microglia as reporters of acute brain injury at sites of impact versus sites experiencing rotational stress 24 h post-mCHI. Consistent with mild injury, a modest 20% reduction in P2Y12 expression was detected by quantitative real-time PCR (qPCR) analysis but only in the impacted region of the cortex. Furthermore, neither an influx of blood-derived immune cells nor changes in microglial expression of CD45, TREM1, TREM2, major histocompatibility complex class II or CD40 were detected. Using magnetic resonance imaging (MRI), small reductions in T2 weighted values were observed but only near the area of impact and without overt tissue damage (blood deposition, edema). Microglial morphology was quantified without cryosectioning artifacts using ScaleA(2) clarified brains from CX3CR1-green fluorescence protein (GFP) mice. The cortex rostral to the mCHI impact site receives greater rotational stress but neither MRI nor molecular markers of microglial activation showed significant changes from shams in this region. However, microglia in this rostral region did display signs of morphologic activation equivalent to that observed in severe CHI. Thus, mCHI-triggered rotational stress is sufficient to cause injuries undetectable by routine MRI that could result in altered microglial surveillance of brain homeostasis. Acute changes in microglial morphology reveal brain responses to unrestrained mild traumatic brain injury In areas subjected to rotational stress distant from impact site In the absence of detectable changes in standard molecular indicators of brain damage, inflammation or microglial activation. That might result in decreased surveillance of brain function and increased susceptibility to subsequent brain insults
Fabrication of free-standing ordered fluorescent polymer nanofibres by electrospinning
The authors are grateful to the Engineering and Physical Sciences Research Council for financial support.We demonstrate a static fabrication approach to make free-standing ordered arrays of fluorescent nanofibres through control of the transverse electrospinning field. The alignment and the density of the nanofibre arrays are optimised by careful design of both the source and collector electrode geometries which can control the transverse electric field over the full path of the jet. In doing so, we fabricate suspended fluorescent nanofibres with an aspect ratio of 10(4), and with a substantially increased density and order parameter (by a factor of similar to 10 compared to random deposition). Electrostatic modelling suggests that the field distribution of the component is the main contribution to the ordering between the plates. This method offers increased efficiency for the creation of ordered fibres collected over a small area and the characterisation of their photoluminescent properties.Publisher PDFPeer reviewe
The Role of the Family in Immigrants' Labor-Market Activity: Evidence from the United States
We use Census of Population microdata for 1980 and 1990 to examine the labor supply and wages of immigrant husbands and wives in the United States in a family context. Earlier research by Baker and Benjamin (1997) posits a family investment model in which, upon arrival, immigrant husbands invest in their human capital while immigrant wives work to provide the family with liquidity during this period. Consistent with this model, they find for Canada that immigrant wives work longer hours upon arrival than comparable natives, but, with time in Canada, they are eventually overtaken by native wives. In contrast, we find that, among immigrants to the United States, both husbands and wives work and earn less than comparable natives upon arrival, with similar shortfalls for men and women. Further, both immigrant husbands and wives have similar, positive assimilation profiles in wages and labor supply and eventually overtake both the wages and the labor supply of comparable natives.
On the transcendence degree of the differential field generated by Siegel modular forms
It is a classical fact that the elliptic modular functions satisfies an
algebraic differential equation of order 3, and none of lower order. We show
how this generalizes to Siegel modular functions of arbitrary degree. The key
idea is that the partial differential equations they satisfy are governed by
Gauss--Manin connections, whose monodromy groups are well-known. Modular theta
functions provide a concrete interpretation of our result, and we study their
differential properties in detail in the case of degree 2.Comment: 21 pages, AmSTeX, uses picture.sty for 1 LaTeX picture; submitted for
publicatio
Using Pilot Systems to Execute Many Task Workloads on Supercomputers
High performance computing systems have historically been designed to support
applications comprised of mostly monolithic, single-job workloads. Pilot
systems decouple workload specification, resource selection, and task execution
via job placeholders and late-binding. Pilot systems help to satisfy the
resource requirements of workloads comprised of multiple tasks. RADICAL-Pilot
(RP) is a modular and extensible Python-based pilot system. In this paper we
describe RP's design, architecture and implementation, and characterize its
performance. RP is capable of spawning more than 100 tasks/second and supports
the steady-state execution of up to 16K concurrent tasks. RP can be used
stand-alone, as well as integrated with other application-level tools as a
runtime system
Pengaturan Level Ketinggian Air Menggunakan Kontrol PID
This paper describes about the application of control system on liquid level control system. The control method used in this system is proportional integral derivative (PID) controller. All control processes and data aquisition is run by using a personal computer (PC). Experiment was done by controlling liquid level in level range 0 - 30 cm. Experiment was also done by using various PID control parameter in which the input signal is step function. Experiment results show that the parameter of liquid level control system are Kp = 1 - 10, Ki = 0,1 - 5 and Kd = 0,1 - 1
The Analysis of Nitrate and Phosphate Concentration with Diatom Abundance in Air Hitam Strait of Meranti Islands Regency of Riau Province
The research was conducted in July 2014 in Air Hitam Strait of Meranti Islands Regency of Riau Province. This research aims to analyze the concentration of nitrate and phosphate and the relationship with diatom abundance. The samples were taken from 4 stations and each station was divided into 3 sampling points. The result showed the average value of nitrate and phosphate concentration were 0.122 mg/L and 0.021 mg/L. This research identified 12 genus of diatom. The highest abundance of diatom was found in Station 3 around of the floating cage locations (162.96 Ind/L) and the lowest was at Station 4 around harbor (111.11 Ind/L). The result of the simple linear regression of nitrate and phosphate concentration showed a positive relation with diatom abundance, that means if the concentration of nitrate and phosphate are raising the diatom abundance was also increasing
Pengaruh Penambahan Minyak Atsiri Kunyit Putih (Kaempferia Rotunda) Pada Edible Film Pati Tapioka Terhadap Aktivitas Antimikroba Dan Sensoris
Tujuan dari penelitian ini untuk mengetahui aktivitas antioksidan minyak atsiri kunyit putih serta pengaruh penambahan minyak kunyit putih terhadap aktivitas antimikroba dan karakteristik sensori edible film tapioka. Aktivitas antioksidan minyak atsiri kunyit putih diuji menggunakan metode DPPH. Pengujian aktivitas antimikroba dilakukan terhadap bakteri Pseudomonas putida FNCC 0070 dan Pseudomonas fluorescens FNCC 0071 sedangkan karakteristik sensori diuji dengan metode perbandingan jamak dan metode hedonik. Aktivitas antioksidan minyak atsiri kunyit putih yang dihasilkan sebesar 1,281% DPPH/mg. Aktivitas antimikroba edible film dengan penambahan 0.1% minyak atsiri kunyit putih mampu menghambat Pseudomonas putida FNCC 0070 sebesar 29,44 mm dan Pseudomonas fluorescens FNCC 0071sebesar 29,99mm. Berdasarkan uji perbandingan jamak diketahui bahwa edible film dengan penambahan 1% minyak atsiri kunyit putih mempunyai karakteristik yang masih mendekati edible film tanpa penambahan minyak atsiri dan juga diterima panelis
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