4,213 research outputs found
Dynamic Compression of in situ Grown Living Polymer Brush: Simulation and Experiment
A comparative dynamic Monte Carlo simulation study of polydisperse living
polymer brushes, created by surface initiated living polymerization, and
conventional polymer monodisperse brush, comprising linear polymer chains,
grafted to a planar substrate under good solvent conditions, is presented. The
living brush is created by end-monomer (de)polymerization reaction after
placing an array of initiators on a grafting plane in contact with a solution
of initially non-bonded segments (monomers). At equilibrium, the monomer
density profile \phi(z) of the LPB is found to decline as \phi(z) ~ z^{-\alpha}
with the distance from the grafting plane z, while the distribution of chain
lengths in the brush scales as c(N) ~ N^{-\tau}. The measured values \alpha =
0.64 and \tau = 1.70 are very close to those, predicted within the framework of
the Diffusion-Limited Aggregation theory, \alpha = 2/3 and \tau = 7/4. At
varying mean degree of polymerization (from L = 28 to L = 170) and effective
grafting density (from \sigma_g = 0.0625 to \sigma_g = 1.0), we observe a
nearly perfect agreement in the force-distance behavior of the simulated LPB
with own experimental data obtained from colloidal probe AFM analysis on
PNIPAAm brush and with data obtained by Plunkett et. al., [Langmuir 2006, 22,
4259] from SFA measurements on same polymer
The First Year IceCube-DeepCore Results
The IceCube Neutrino Observatory includes a tightly spaced inner array in the
deepest ice, called DeepCore, which gives access to low-energy neutrinos with a
sizable surrounding cosmic ray muon veto. Designed to be sensitive to neutrinos
at energies as low as 10 GeV, DeepCore will be used to study diverse physics
topics with neutrino signatures, such as dark matter annihilations and
atmospheric neutrino oscillations. The first year of DeepCore physics
data-taking has been completed, and the first observation of atmospheric
neutrino-induced cascades with IceCube and DeepCore are presented.Comment: 4 pages, 3 figures, TAUP 2011 (Journal of Physics: Conference Series
(JCPS)
Crimean-congo hemorrhagic fever: Case series from a medical center in golestan province, Northeast of Iran (2004-2006)
Crimean-Congo hemorrhagic fever (CCHF) is a widely distributed lethal disease, worldwide. Humans are usually infected with CCHF virus through a tick bite or close contact with viral contaminated tissues or with blood of domestic animals or of infected patients. The present study reports six cases of CCHF, who were in contact with both infected tissues and blood from sheep. In some regions like Golestan province (North of Iran), clinician suspicion may have an important role in early diagnosis and treatment of the disease. Conservative therapy (intensive monitoring) and prescription of antiviral medication (Ribavirin) accompanied with corticosteroids, was useful at the early stage of CCHF
Ultrahigh Energy Cosmic Rays and Neutrinos
The observation of neutrinos from cosmic accelerators will be revolutionary.
High energy neutrinos are closely connected to ultrahigh energy cosmic rays and
their sources. Cosmic ray sources are likely to produce neutrinos and the
propagation of ultrahigh cosmic rays from distant sources can generate PeV to
ZeV neutrinos. We briefly review recent progress on the observations of
ultrahigh energy cosmic rays and their implications for the future detections
of high energy neutrinos.Comment: 6 pages, 2 figures, Proceedings of NOW (Neutrino Oscillation
Workshop) 2010, to appear in Nucl. Phys. B (Proc. Suppl.
Hematologic, hepatic, and renal function changes in hospitalized patients with Middle East respiratory syndrome coronavirus
Background
There are no longitudinal data on the changes in hematologic, hepatic, and renal function findings in patients with Middle East respiratory syndrome coronavirus (MERS‐CoV) infection.
Methods
This is a retrospective cohort study of 16 MERS‐CoV patients, to describe the hematological, hepatic, and renal findings of patients with MERS‐CoV.
Results
During the 21 days of observation, there was no significant change in the hepatic panel or creatinine tests. There was a significant increase in the mean ± SD of the white blood cell count from 8.3 ± 4.6 to 14.53 ± 7 (P value = 0.001) and an increase in mean ± SD of the absolute neutrophil count from 6.33 ± 4.2 to 12 ± 5.5 (P value = 0.015). Leukocytosis was observed in 31% (5/16) of the patients on day 1 and in 80% (4/5) on day 21. Transient leukopenia developed in 6% (1/16) of the patients on day 1 and in 13% (1/8) on day 8. None of the patients had neutropenia. Lymphopenia was a prominent feature with a rate of 44% (7/16) of the patients on day 1 and 60% (3/5) on day 21. Lymphocytosis was not a feature of MERS‐CoV infection. Thrombocytopenia developed in 31% (5/16) of the patients on day 1 and 40% (2/5) on day 21. Thrombocytosis was not a prominent feature and was observed in 6% (1/16) of the patients on day 1 and 17% (1/6) on day 9.
Conclusions
Patients with MERS‐CoV infection showed variable hematologic parameters over time. Lymphocytosis and neutropenia were not features of MERS‐CoV infection
Morphometric and meristic characteristics of Vimba vimba persa in Sefidrud River
During years 1999-2001, a series of sampling was carried out in Sefidrud River to study morphometric and meristic characteristics of Caspian Vimba. 149 specimens were collected and then necessary measurements were considered and following results were obtained: T.L= 171.2±31.6mm, W= 62.9±19.7g, age= 3.49±0.9 year, average number of scales on lateral line = 50.83±1.8, branched ray of dorsal and anal fins = 7.96±0.2 and 17.58±1.0 respectively. The mean morphometric measurements with respect to body standard length (%) were: head length 24.47±1.9, eye diameter 6.10±1.07, body maximum depth 26.17±1.4, dorsal fin height and length 20.22±1.5 and 10.96±0.8, anal fin height and length 12.66±0.8 and 18.17±1.5, pectoral fin length 18.17±1.2, ventral fin length 14.97±1.1, pecto-ventral fins distance 24.18±l.7 and ventral-anal distance 20.00±1.5 and pre-dorsal distance 52.21±1.7. Adults and juveniles showed difference in 2 meristic and 15 morphometric parameters. On the other hand, the adult males and females showed difference in 16 morphometric parameters (esp. body depth, lengths of dorsal, pectoral, pelvic and anal fins). Also, adult males have a series of fine epithelial tubercles on head and body and their color is darker with more reddish anal and ventral fins
Letter to the Editor on: Prostate-specific antigen density is predictive of outcome in suboptimal prostate seed brachytherapy
In this study, a novel method was developed to measure acidic and basic drugs in biological and wastewater samples. The method used magnetic nanoparticles based on Vortex-Assisted Dispersive Micro-Solid Phase Extraction (SPE) and then identifying with HPLC-UV. The magnetic nanoparticle (Fe3O4@SiO2@Kit-6@NH2) has been used as an efficient adsorbent for the extraction of acidic and basic drugs ibuprofen (IFB), fenoprofen calcium (FPC), methocarbamol (MTC), and clonazepam (CZP). The magnetic nanoparticle was characterized by techniques including SEM, XRD, EDX, and FT-IR. The effect of various parameters in the V-D-μ-SPE method was studied completely through the design of the response surface methodology (RSM) of the Box–Behnken design (BBD) based response method and the utility function. The parameters affecting the extraction efficiency were optimized including sample pH, adsorbent amount, absorption time, the salt concentration in the sample solution, CTAB of concentration, desorption time, and the volume of an eluent. After optimization, the limit of detection and calibration curve in the linear range were obtained 0.062–0.32 μg L−1 and 0.1–800 μg L−1, respectively. Its linear correlation was R2> 0.9951. The relative standard deviation (n = 5) was between 2.4 and 5.1. Finally, this method was used to determine target analytes in human serum, urine, and wastewater. • In this study, for the first time, a novel method for the determination of some drugs from human serum, urine, and wastewater samples. • The Synthesized Fe3O4@SiO2@Kit-6@NH2 NPs based V-D-μ-SPE was characterized by techniques including SEM, XRD, EDX, and FT-IR. • The effects of various parameters in the V-D-μ-SPE methods were studied through the design of the RSM of BBD. © 202
Studying natural reproduction, spawning grounds and spawning period of Vimba vimba persa population in Sefid-roud river, Guilan Province in north Iran
To evaluate spawning status of Vimba vimba ,population in Sefid-roud river, 621 breeders, 1136 larvae, fries and fingerlings were caught in the river using beach seine, cast-net and electro-choker over the years 1999-2000. We found that the fish started spawning migration in March and continued it until July with its peak occurring between mid-April to late-May. Fork length was 116 - 208 mm (153.1 ± 17.95) in male specimens and 122 - 222 mm (173.5 ± 1 6.46) in females. Total body weight ranged 21.1-116.1g (52.92 ± 19.23) in males and 23.1 - 170.0 g (77.90 ± 22.88) in females. Males aged 2-6 years (3.53±0.86) and females aged 3-7 years (4.19±0.92) participated in the spawning with their maturity age being calculated as 2 and 3 years respectively. In all, breeders were composed of 51.82% males and 48.18% females with the ratio being significantly different only in May. Gonad weight was 1.13-7.92 g (Avg. 2.89±0.29) in males and 3.21-25.47g (Avg. 10.40±1.52) in females. We found the highest gonad weight for the fish in June and that the gonad weight in female breeders increased upwards of the estuary. Gonado-somatic index was 19-21% in 85.7% of the females and 3-8% in 95.5% of the males. Spawning of the species took place during day and night from late May to late June with its peak in May in water temperature ranging 18-29 degrees centigrade on pebble and gravel pounds from 25 to 75kms away from estuary. The Disaam tributary was distinguished as the major spawning area for the species
Library spaces designed with students in mind: an evaluation study of University of Queensland libraries at St Lucia campus
This paper identifies the design qualities of library spaces that matter the most foruniversity students. Drawing upon the data from an online survey made available to students from the University of Queensland, Australia, a number of design-related considerations are examined including: acoustics, furniture, interior architecture, lighting, and thermal comfort. 1505 students completed the survey, which aimed to assess how effective and responsive library spaces are in meeting students’ needs and supporting their learning experiences. The survey included ‘Likert scale questions’ requiring students to rate their levels of satisfaction with different aspects of library spaces and ‘open-ended questions’ asking students to elucidate their ratings. Findings revealed that the qualities of physical spaces were ranked as the third mostsignificant category of reasons accounting for students’ preference for certain library buildings over others, and for their frequency of visit (behind “location” of the library building and then “access to books and course-related materials or resources”). Design-related themes which emerged from qualitative analysis highlighted students’ awareness of the impacts that the design of spaces and furniture can have on their learning experiences. The study concludes with recommendations informed by students’ expectations, needs and preferences in relation to the qualities and features of library spaces
Measurement of zero degree single photon energy spectra for sqrt(s) = 7TeV proton-proton collisions at LHC
In early 2010, the Large Hadron Collider forward (LHCf) experiment measured
very forward neutral particle spectra in LHC proton-proton collisions. From a
limited data set taken under the best beam conditions (low beam-gas background
and low occurance of pile-up events), the single photon spectra at sqrt(s)=7TeV
and pseudo-rapidity (eta) ranges from 8.81 to 8.99 and from 10.94 to infinity
were obtained for the first time and are reported in this paper. The spectra
from two independent LHCf detectors are consistent with one another and serve
as a cross check of the data. The photon spectra are also compared with the
predictions of several hadron interaction models that are used extensively for
modeling ultra high energy cosmic ray showers. Despite conservative estimates
for the systematic errors, none of the models agree perfectly with the
measurements. A notable difference is found between the data and the DPMJET
3.04 and PYTHIA 8.145 hadron interaction models above 2TeV where the models
predict higher photon yield than the data. The QGSJET II-03 model predicts
overall lower photon yield than the data, especially above 2TeV in the rapidity
range 8.81<eta<8.99
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