1,144 research outputs found
Laser-induced radial birefringence and spin-to-orbital optical angular momentum conversion in silver-doped glasses
Samples of Ag/Na ion-exchanged glass that have been subject to
intense laser irradiation may develop novel optical properties, as a
consequence of the formation of patterns of silver nanoparticles and other
structures. Here, we report the observation of a laser-induced permanent
transverse birefringence, with the optical axis forming a radial pattern, as
revealed by the spin-to-orbital angular momentum conversion occurring in a
probe light beam. The birefringence pattern can be modeled well as resulting
from thermally-induced stresses arising in the silver-doped glass during laser
exposure, although the actual mechanism leading to the permanent anisotropy is
probably more complex.Comment: 3 pages, 3 figure
A Simplest Swimmer at Low Reynolds Number: Three Linked Spheres
We propose a very simple one-dimensional swimmer consisting of three spheres
that are linked by rigid rods whose lengths can change between two values. With
a periodic motion in a non-reciprocal fashion, which breaks the time-reversal
symmetry as well as the translational symmetry, we show that the model device
can swim at low Reynolds number. This model system could be used in
constructing molecular-size machines
170Effectiveness of metronidazole on cyclosporine-induced gingivial hyperplasia in bone marrow and kidney transplant patients:A prospective, double-blinded controlled clinical trial
Assessing the impact of employing machine learning-based baseline load prediction pipelines with sliding-window training scheme on offered flexibility estimation for different building categories
The present study is focused on assessing the impact of the performance of baseline load prediction pipelines on the estimation (by the grid operator) accuracy of the flexibility offered by different categories of buildings. Accordingly, the corresponding impact of employing different machine learning (ML) algorithms, with sliding-window and offline training schemes, for hour-ahead baseline load prediction has been investigated and compared. Using a smart meter measurements dataset, training window sizes and the most promising pipeline for each building category are first identified. Next, the consumption profiles of five buildings (belonging to each category), with the regular operation (baseline load) and while offering flexibility, are physically simulated. Finally, the identified pipelines are used for predicting the baseline loads, and the resulting error in estimating the provided flexibility is determined. Obtained results demonstrate that the identified most promising prediction pipeline (extra trees algorithm with a sliding window of 5 weeks) offers a notably superior performance compared to that of offline training (average R2 score of 0.91 vs. 0.87). Employing these pipelines permits estimating the provided flexibility with acceptable accuracy (flexibility index's mean relative error between -2.45% to +2.79%), permitting the grid operator to guarantee fair compensation for buildings' offered flexibility
Ion-Exchanged Waveguides in Glass Doped with PbS Quantum Dots
The lowest-loss (≤1 dB/cm) ion-exchanged waveguides in glass doped with PbS quantum dots are presented. Near-field mode profile and refractive index profile using the refracted near-field technique were measured for these waveguides. We demonstrate that the optical properties of this glass unchanged during the ion-exchange process
Prevalence of chronic kidney disease and its associated risk factors: The first report from Iran using both microalbuminuria and urine sediment
Background: The incidence of major risk factors of chronic kidney disease (CKD) in the world is on the rise, and it is expected that this incidence and prevalence, particularly in developing countries, will continue to increase. Using data on urinary sediment and microalbuminuria, we aimed to estimate the prevalence of CKD in northeast Iran. Methods: In a cross-sectional study, the prevalence of CKD in a sample of 1557 regionally representative people, aged � 18 years, was analyzed. CKD was determined based on glomerular filtration rate (GFR) and microalbuminuria. Life style data, urine and blood samples were collected. Urine samples without any proteinuria in the initial dipstick test were checked for qualitative microalbuminuria. If the latter was positive, quantitative microalbuminuria was evaluated. Results: 1557 subjects with a mean age of 56.76 ± 12.04 years were enrolled in this study. Based on the modifcation of diet in renal disease (MDRD) equation, 137 subjects (8.89%) were categorized as CKD stages III-V. Based on urine abnormalities, the prevalence of combined CKD stages I and II was 10.63%, and based on macro- and microalbuminuria it was 14.53%. The prevalence of CKD was significantly associated with sex, age, marital status, education, diabetes mellitus (DM), hypertension (HTN), ischemic heart disease (IHD), waist to hip ratio, myocardial infarction (MI), and cerebrovascular accident (CVA). Conclusion: CKD and its main risk factors are common and represent a definite health threat in this region of Iran. Using and standardizing less expensive screening tests in low resource countries could be a good alternative that may improve the outcome through early detection of CKD
Forces Induced by Non-Equilibrium Fluctuations: The Soret-Casimir Effect
The notion of fluctuation-induced forces is generalized to the cases where
the fluctuations have nonequilibrium origin. It is shown that a net force is
exerted on a single flat plate that restricts scale-free fluctuations of a
scalar field in a temperature gradient. This force tends to push the object to
the colder regions, which is a manifestation of thermophoresis or the Soret
effect. In the classic two-plate geometry, it is shown that the Casimir forces
exerted on the two plates differ from each other, and thus the Newton's third
law is violated.Comment: 8 pages, 5 postscript figures, uses (old) RevTe
Acute phase proteins response to feed deprivation in broiler chickens
Feed deprivation in poultry farming imposes some degree of stress to the birds, and adversely affects their well -being. Serum levels of acute phase proteins (APP) are potential physiological indicators of stress attributed to feed deprivation. However, it has not been determined how long it takes for a measurable APP response to stressors to occur in avian species. An experiment was designed to delineate the APP and circulating levels of corticosterone responses in commercial broiler chickens to feed deprivation for 30 h. It was hypothesized that feed deprivation would elicit both APP and corticosterone (CORT) reactions within 30 h that is probably associated with stress of hunger. Twenty-one day old birds were subjected to one of 5 feed deprivation periods: 0 (ad libitum, AL), 6, 12, 18, 24, and 30 h. Upon completion of the deprivation period, blood samples were collected to determine serum CORT, ovotransferrin (OVT), α1-acid glycoprotein (AGP), and ceruloplasmin (CP) concentrations. Results showed that feed deprivation for 24 h or more caused a marked elevation in CORT (P = 0.002 and P < 0.0001, respectively) when compared to AL. However, increases in AGP (P = 0.0005), CP (P = 0.0002), and OVT (P = 0.0003) were only noted following 30 h of feed deprivation. It is concluded that elicitation of AGP, CP, and OVT response may represent a more chronic stressful condition than CORT response in assessing the well-being of broiler chickens
- …