1,697 research outputs found
Velocity of sound in a Bose-Einstein condensate in the presence of an optical lattice and transverse confinement
We study the effect of the transverse degrees of freedom on the velocity of
sound in a Bose-Einstein condensate immersed in a one-dimensional optical
lattice and radially confined by a harmonic trap. We compare the results of
full three-dimensional calculations with those of an effective 1D model based
on the equation of state of the condensate. The perfect agreement between the
two approaches is demonstrated for several optical lattice depths and
throughout the full crossover from the 1D mean-field to the Thomas Fermi regime
in the radial direction.Comment: final versio
Diamonds as timing detectors for MIP: The HADES proton-beam monitor and start detectors
This paper gives an overview of a recent development of measuring time of
flight of minimum-ionizing particles (MIP) with mono-crystalline diamond
detectors. The application in the HADES spectrometer as well as test results
obtained with proton beams are discussed.Comment: submitted to Nuclear Instruments and Methods
First-Principles Study on Electron Conduction in Sodium Nanowire
We present detailed first-principles calculations of the electron-conduction
properties of a three-sodium-atom nanowire suspended between semi-infinite
crystalline Na(001) electrodes during its elongation. Our investigations reveal
that the conductance is ~1 G0 before the nanowire breaks and only one channel
with the characteristic of the orbital of the center atom in the nanowire
contributes to the electron conduction. Moreover, the channel fully opens
around the Fermi level, and the behavior of the channel-current density is
insensitive to the structural deformation of the nanowire. These results verify
that the conductance trace as a function of the electrode spacing exhibits a
flat plateau at ~1 G0 during elongation.Comment: 8 pages, 5 figure
Guaranteeing Canadian lamb meat quality using near-infrared spectroscopy on intact rack
Lamb racks from commercial carcasses were scanned using near-infrared spectroscopy. The prediction accuracies (R 2) for meat quality traits were assessed. Prediction accuracy ranged between 0.40 and 0.94. When predicted values were used to classify meat based on quality, 88.7%–95.2% of samples were correctly classified as quality guaranteed
Superfluid to Mott insulator transition in one, two, and three dimensions
We have created one-, two-, and three-dimensional quantum gases and study the
superfluid to Mott insulator transition. Measurements of the transition using
Bragg spectroscopy show that the excitation spectra of the low-dimensional
superfluids differ significantly from the three-dimensional case
Tourism for Sustainable Mountains Development:A Comparative Law Perspective
This contribution aims to assess whether existing mountain laws at the regional and national levels are equipped to ensure environmental protection in regulating and promoting mountain tourism, in the light of relevant guidance provided by the Convention on Biological Diversity. Two major challenges are identified: ensuring the full and effective participation of mountain communities in decision-making related to mountain tourism development, and the fair and equitable sharing of the benefits arising from sustainable mountain tourism
Blood on Their Hands: Settler Colonial States in the Arctic
The Arctic is currently the most rapidly warming region in the world. Modern-day media has been transfixed by the image of the poor polar bear, eeking out a difficult living as the sea ice they depend on has been melting. What often remains outside of the frame, however, are the more complex questions about how we got to this point of extreme climate change. Linking the genocidal histories of Indigenous assimilation in the Arctic to the modern-day ecological crises plaguing the region introduces the state as an overlooked climate polluter. While Arctic communities are all on the frontlines of climate change, the Indigenous nations bear these burdens unequally, facing the legacies and everyday enactments of settler colonial violence.
Written from the perspective of a non-Indigenous Global North citizen, this paper utilizes the framework of David Pellow’s Critical Environmental Justice to argue that the Arctic’s role as a stronghold for state power is exactly what makes it a site of critical environmental injustice. On the heels of the Arctic becoming a new frontier for deep-sea mining and territorial expansion, I urge settler scientists and other settler citizens of the Arctic states to take action against the empires in which they live
Effect of partial replacement of fishmeal with Eichhornia crassipes on growth and survival of Labeo rohita (Hamilton, 1822) juveniles
The objective of the study was to find out the effect of partial replacement of fish meal in the diet of Labeo rohita juveniles. In this experiment, the data pertaining to growth, survival rate, feed conversion ratio, protein efficiency ratio of L. rohita at partial replacement of fishmeal with E. crassipes were evaluated. For that purpose fry of approximately equal weight (57.97mg ± 1.25) were distributed in groups of 15 to each four aquaria at 0% (T1), 10% (T2), 20% (T3), 30% (T4) and 40% (T5) inclusion levels of aquatic macrophyte, Eichhornia crassipes. Maximum mean weight gain (235.25 ± 11.04 mg) was observed in T1 and minimum (165.06 ± 10.93 mg) was observed in T5 at the end of the experiment. Among the treatments tested, the highest survival (89.99% ± 1.93) was recorded in treatment T1 and minimum was found in T4 (79.99% ± 2.72). Lowest FCR was recorded in treatment T3 (2.02 ± 0.39) and highest was found in T5 (3.08 ± 0.59). Higher SGR was observed in treatment T1 (297.15 ± 18.78%) and minimum was observed in T5 (182.74 ± 18.45%). The study revealed a decrease in the growth performance indices as the percentage of water hyacinth increases. In present study also there was not much difference in growth rate upto 20% incorporation of E. crassipes in the diet. Also, significant difference was observed among treatments with respect to feed utilization (P<0.05)
Combined effects of time spent in physical activity, sedentary behaviors and sleep on obesity and cardio-metabolic health markers: a novel compositional data analysis approach
<div><p>The associations between time spent in sleep, sedentary behaviors (SB) and physical activity with health are usually studied without taking into account that time is finite during the day, so time spent in each of these behaviors are codependent. Therefore, little is known about the combined effect of time spent in sleep, SB and physical activity, that together constitute a composite whole, on obesity and cardio-metabolic health markers. Cross-sectional analysis of NHANES 2005–6 cycle on N = 1937 adults, was undertaken using a compositional analysis paradigm, which accounts for this intrinsic codependence. Time spent in SB, light intensity (LIPA) and moderate to vigorous activity (MVPA) was determined from accelerometry and combined with self-reported sleep time to obtain the 24 hour time budget composition. The distribution of time spent in sleep, SB, LIPA and MVPA is significantly associated with BMI, waist circumference, triglycerides, plasma glucose, plasma insulin (all p<0.001), and systolic (p<0.001) and diastolic blood pressure (p<0.003), but not HDL or LDL. Within the composition, the strongest positive effect is found for the proportion of time spent in MVPA. Strikingly, the effects of MVPA replacing another behavior and of MVPA being displaced by another behavior are asymmetric. For example, re-allocating 10 minutes of SB to MVPA was associated with a lower waist circumference by 0.001% but if 10 minutes of MVPA is displaced by SB this was associated with a 0.84% higher waist circumference. The proportion of time spent in LIPA and SB were detrimentally associated with obesity and cardiovascular disease markers, but the association with SB was stronger. For diabetes risk markers, replacing SB with LIPA was associated with more favorable outcomes. Time spent in MVPA is an important target for intervention and preventing transfer of time from LIPA to SB might lessen the negative effects of physical inactivity.</p></div
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