284 research outputs found
Thermodynamic properties of an interacting hard-sphere Bose gas in a trap using the static fluctuation approximation
A hard-sphere (HS) Bose gas in a trap is investigated at finite temperatures
in the weakly-interacting regime and its thermodynamic properties are evaluated
using the static fluctuation approximation (SFA). The energies are calculated
with a second-quantized many-body Hamiltonian and a harmonic oscillator wave
function. The specific heat capacity, internal energy, pressure, entropy and
the Bose-Einstein (BE) occupation number of the system are determined as
functions of temperature and for various values of interaction strength and
number of particles. It is found that the number of particles plays a more
profound role in the determination of the thermodynamic properties of the
system than the HS diameter characterizing the interaction, that the critical
temperature drops with the increase of the repulsion between the bosons, and
that the fluctuations in the energy are much smaller than the energy itself in
the weakly-interacting regime.Comment: 34 pages, 24 Figures. To appear in the International Journal of
Modern Physics
Thermoelectric properties and high-temperature stability of the Ti<sub>1-x</sub>V<sub>x</sub>CoSb<sub>1-x</sub>Sn<sub>x</sub> half-Heusler alloys
The thermoelectric properties and high-temperature stability of the Ti1−xVxCoSb1−xSnx solid solution have been investigated.</p
An interactive atlas for marine biodiversity conservation in the Coral Triangle
An online atlas of the Coral Triangle region of the Indo-Pacific
biogeographic realm was developed. This online atlas consists of the three
interlinked parts: (1)Â Biodiversity Features; (2)Â Areas of Importance for
Biodiversity Conservation; (3)Â recommended priorities for Marine Protected
Area (MPA) Network Expansion (http://www.marine.auckland.ac.nz/CTMAPS).
The first map, Biodiversity Features, provides comprehensive data on the
region's marine protected areas and biodiversity features, threats, and
environmental characteristics. The second provides spatial information on
areas of high biodiversity conservation values, while the third map shows
priority areas for expanding the current Coral Triangle MPA network. This
atlas provides the most comprehensive biodiversity datasets that have been
assembled for the region. The datasets were retrieved and generated
systematically from various open-access sources. To engage a wider audience
and to raise participation in biodiversity conservation, the maps were
designed as an interactive and online atlas. This atlas presents
representative information to promote a better understanding of the key
marine and coastal biodiversity characteristics of the region and enables the
application of marine biodiversity informatics to support marine
ecosystem-based management in the Coral Triangle region.</p
Clinical Study One-Haptic Fixation of Posterior Chamber Intraocular Lenses without Scleral Flaps
is properly cited. Purpose. To assess visual results and complications of a modified technique of posterior chamber intraocular lenses (PC IOLs) in aphakic eyes without scleral flaps. Methods. Modified one-haptic scleral fixation was performed in one eye each of 25 patients with aphakia and insufficient capsule support. Follow-up period was six months. Outcome measures included best-corrected visual acuity, intraocular pressure (IOP), and postoperative complications. Results. The study included 15 males and 10 females. The preoperative best-corrected visual acuity (BCVA) ranged from 5/60 to 6/9. The operation time ranged from 25 to 45 minutes (mean 35.25 ± 5.34 min). Anterior vitrectomy was performed in 12 cases (48%). There was no major IOL decentration. The final BCVA ranged from 6/36 to 6/9. Seven cases (28%) showed postoperative glaucoma, five cases (20%) had temporary hypotony, and hyphema in 2 eyes (8%). No cases of suture erosion, postoperative endophthalmitis, retinal detachment, or IOL dislocation were detected. Conclusion. This technique of one-haptic scleral fixation of posterior chamber IOLs is a good choice in presence of insufficient capsule support. It reduces the operation time, achieves the IOL stability, and minimizes postoperative suture-related complications
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Visibility through clutter: How could brands cut through advertising clutter on Instagram?
Meeting abstractUpcoming businesses from all sectors are heavily relying on Instagram in order to build their brand with respect to its user friendliness, low cost, and accessibility. The application offers an abundance of business-friendly tools allowing organizations to build an online store, create collaborations, or even sponsor their own content in order to reach a wider audience greater than their current followership
Assessment of genetic diversity in Iraqi camel breeds using Cytochrome b
Joudi breed were collected from Basrah, Al-Muthanna, Najaf, Babylon, and Wasit (10 samples each). As well as 15 samples of the Khawar breed from Anbar and 15 samples of the Hurra breed from DhiQar. The analysis of molecular variance (AMOVA) was employed This study aimed to investigate the genetic diversity, population structure, and demographic history of Iraq camel breeds. Eighty blood samples were randomly collected from unrelated animals from different parts of Iraq. Fifty samples of the Joudi breed were collected from Basrah, Al-Muthanna, Najaf, Babylon, and Wasit (10 samples each). As well as 15 samples of the Khawar breed from Anbar and 15 samples of the Hurra breed from DhiQar. The analysis of molecular variance (AMOVA) was employed in order to determine the genetic variability within and among populations of this camel breeds. The neutrality tests and mismatch distribution analysis were also applied to assess the neutrality and demographic expansion of the populations, respectively. The results revealed a total of 16 different haplotypes with high haplotype diversity (0.648) and low-nucleotide diversity (0.00109). The haplotypes of the Cytb gene were 15 haplotypes, 10 of which were in the Joudi breed, 6 in the Hurra breed and one haplotype in the Khwar breed. The haplotype H-2 was common to the three breeds. The variations within and among populations accounted for 94.36 and 5.64% of the total variation, respectively. The results of the neutrality test for Cytb showed that the Joudi and Hurra breeds had negative values for both Tajima's D and Fu's Fs. The highest values were -1.00737 and -1.98591 for the Hurra breed and the lowest values were for the Joudi breed (-2.14737 and -6.59079 respectively). In the Khwar breed, the values were zero for Tajima's D and Fu's Fs and the obtained result conforms to the model of population expansion (t > 0 and θ1> θ0) for Joudi and Hurra breeds
Methods for the Study of Marine Biodiversity
Recognition of the threats to biodiversity and its importance to society has led to calls for globally coordinated sampling of trends in marine ecosystems. As a step to defining such efforts, we review current methods of collecting and managing marine biodiversity data. A fundamental component of marine biodiversity is knowing what, where, and when species are present. However, monitoring methods are invariably biased in what taxa, ecological guilds, and body sizes they collect. In addition, the data need to be placed, and/or mapped, into an environmental context. Thus a suite of methods will be needed to encompass representative components of biodiversity in an ecosystem. Some sampling methods can damage habitat and kill species, including unnecessary bycatch. Less destructive alternatives are preferable, especially in conservation areas, such as photography, hydrophones, tagging, acoustics, artificial substrata, light-traps, hook and line, and live-traps. Here we highlight examples of operational international sampling programmes and data management infrastructures, notably the Continuous Plankton Recorder, Reef Life Survey, and detection of Harmful Algal Blooms and MarineGEO. Data management infrastructures include the World Register of Marine Species for species nomenclature and attributes, the Ocean Biogeographic Information System for distribution data, Marine Regions for maps, and Global Marine Environmental Datasets for global environmental data. Existing national sampling programmes, such as fishery trawl surveys and intertidal surveys, may provide a global perspective if their data can be integrated to provide useful information. Less utilised and emerging sampling methods, such as artificial substrata, light-traps, microfossils and eDNA also hold promise for sampling the less studied components of biodiversity. All of these initiatives need to develop international standards and protocols, and long-term plans for their governance and support.published_or_final_versio
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