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Athletes with Mental Health Illnesses
The focus for this research study is to understand the development of mental health symptoms that result from sports engagement. Participating in sports for several years within different developmental stages of human life can increase the probability of identity conflict and mental distress. This study addresses the risk factors that contribute to the development of mental health illnesses from former athletesâ perspectives through qualitative research. The study includes former male and female participants ages 18 and older as well as their family members, friends, sports stakeholders, sports officials, coaches, social workers, and athletic training staff. This study was conducted from the constructivism perspective with a theoretical orientation concentrating on the Ecological Systems Theory. The social work implications of this study are to provide practitioners and community partners that work in athlete mental health with a better understanding of the specific needs experienced by athletes post athletic career. Common themes constructed by ex-athletes found in this study include identity crises, lack of social support systems, struggles of career transition, and mental health symptomology
Surface Diffusion Studies by Analysis of Cluster Growth Kinetics
The approach to thermodynamic equilibrium is the driving force for kinetic processes in adsorbate and thin film structure formation. Macroscopic thermodynamic concepts may be used to predict the rates of nucleation, cluster formation and cluster growth. They involve mass transport concepts usually limited by surface concentration gradients. Time and temperature dependence of nucleation and cluster growth, described in terms of cluster ripening mechanism, therefore reveal information on the microscopic surface diffusion processes, including surface structure and surface energies. Examples of structures studied include, Ga, Sn, and Ge on Si, As terminated Si and GaAs surfaces where the activation energies for clustering are obtained without using laterally resolved techniques requiring Îźm-patch deposition. The results are in agreement with activation energies found in nucleation experiments of Ag on Si.
The concentration dependence of the surface diffusion coefficient in clustering systems is connected to the difference between the intrinsic diffusion coefficient and the chemical or mass transport diffusion coefficient. The difference results from the analysis of an extended Einstein relation for diffusion in these systems. The intrinsic diffusion coefficient of Sn and Ga on Si is concentration independent in cluster growth experiments. Literature data for surface diffusion of Ag/Ge(111) and O/W(110) show a concentration dependence which is in good agreement with the dependence predicted for the chemical diffusion coefficient by this model
Kinetic theory of cluster impingement in the framework of statistical mechanics of rigid disks
The paper centres on the evaluation of the function n(theta)=N(theta)/N0,
that is the normalized number of islands as a function of coverage 0<theta<1,
given N0 initial nucleation centres (dots) having any degree of spatial
correlation. A mean field approach has been employed: the islands have the same
size at any coverage. In particular, as far as the random distribution of dots
is concerned, the problem has been solved by considering the contribution of
binary collisions between islands only. With regard to correlated dots, we
generalize a method previously applied to the random case only. In passing, we
have made use of the exclusion probability reported in [S. Torquato, B. Lu, J.
Rubinstein, Phys.Rev.A 41, 2059 (1990)], for determining the kinetics of
surface coverage in the case of correlated dots, improving our previous
calculation [M. Tomellini, M. Fanfoni, M. Volpe Phys. Rev.B 62, 11300, (2000)].Comment: 10 pages, 3 figure
ENHANCED TELEPHONY USING HUMAN INAUDIBLE DATA OVER VOICE CHANNEL
A telephone, such as a mobile phone, places a telephone call to another telephone by transmitting a signal (e.g., digital or analog) indicative of a sound wave. The signal indicative of the sound wave encodes sound data over a voice channel. The sound data includes human audible data, such as data indicative of sounds (e.g., voice) captured by a microphone. That is, the frequency of the sound wave that encodes the human audible data is within a frequency range audible by humans. The sound data also includes human inaudible data, such as a telephone number of the calling device, an image of the caller, a location of the calling device, associated with the calling telephone or a user of the calling telephone. That is, the frequency of the sound wave that encodes the human inaudible data is above the frequency range audible by humans. When the recipient telephone receives the signal indicative of the sound data, the recipient telephone converts the signal to a human audible sound wave that encodes the human audible data. The recipient telephone may utilize the human inaudible data to enhance the functionality of the call. For example, the recipient telephone may display the human inaudible data (e.g., a phone number of the calling device and/or an image of the caller) or connect a video call via URL encoded in the human inaudible data
A complex pathway for 3 ' processing of the yeast U3 snoRNA
Mature U3 snoRNA in yeast is generated from the 3â˛-extended precursors by endonucleolytic cleavage followed by exonucleolytic trimming. These precursors terminate in poly(U) tracts and are normally stabilised by binding of the yeast La homologue, Lhp1p. We report that normal 3Ⲡprocessing of U3 requires the nuclear Lsm proteins. On depletion of any of the five essential proteins, Lsm2â5p or Lsm8p, the normal 3â˛-extended precursors to the U3 snoRNA were lost. Truncated fragments of both mature and pre-U3 accumulated in the Lsm-depleted strains, consistent with substantial RNA degradation. Pre-U3 species were co-precipitated with TAP-tagged Lsm3p, but the association with spliced pre-U3 was lost in strains lacking Lhp1p. The association of Lhp1p with pre-U3 was also reduced on depletion of Lsm3p or Lsm5p, indicating that binding of Lhp1p and the Lsm proteins is interdependent. In contrast, a tagged Sm-protein detectably co-precipitated spliced pre-U3 species only in strains lacking Lhp1p. We propose that the Lsm2â8p complex functions as a chaperone in conjunction with Lhp1p to stabilise pre-U3 RNA species during 3Ⲡprocessing. The Sm complex may function as a back-up to stabilise 3Ⲡends that are not protected by Lhp1p
Towards fabrication of ordered gallium nanostructures by laser manipulation of neutral atoms: study of self-assembling phenomena
Surface diffusion has an impact on the lateral resolution of nanostructures
in bottom-up atom nanofabrication. In this paper we study the effects of the
gallium atoms self-assembled on silicon surfaces (100) patterned with trenches
at different slopes. These particular substrate morphologies have been made to
enable an effective deposition rate variation along the surface. In this way we
experimentally mimic the effect of the atomic flux modulation created by
standing wave during an atom nanofabrication experiment. Even if we observe
self organization of gallium atoms on the surface, we conclude that the
nano-islands are not affected by surface diffusion processes and the effective
variation of the deposition rate per unit area is the dominant factor affecting
the growth differences along the surface. This result demonstrates that the
gallium atoms self-organization should not prevent the observation of a
periodic nano-patterning created by atom nano-fabrication techniques.Comment: 7 pages, 5 figures, EMRS conference procee
Three novel components of the human exosome
Contains fulltext :
186951.pdf (publisher's version ) (Open Access)The yeast exosome is a complex of 3' --> 5' exoribonucleases. Sequence analysis identified putative human homologues for exosome components, although several were found only as expressed sequence tags. Here we report the cloning of full-length cDNAs, which encode putative human homologues of the Rrp40p, Rrp41p, and Rrp46p components of the exosome. Recombinant proteins were expressed and used to raise rabbit antisera. In Western blotting experiments, these decorated HeLa cell proteins of the predicted sizes. All three human proteins were enriched in the HeLa cells nucleus and nucleolus, but were also clearly detected in the cytoplasm. Size exclusion chromatography revealed that hRrp40p, hRrp41p, and hRrp46p were present in a large complex. This cofractionated with the human homologues of other exosome components, hRrp4p and PM/Scl-100. Anti-PM/Scl-positive patient sera coimmunoprecipitated hRrp40p, hRrp41p, and hRrp46p demonstrating their physical association. The immunoprecipitated complex exhibited 3' --> 5' exoribonuclease activity in vitro. hRrp41p was expressed in yeast and shown to suppress the lethality of genetic depletion of yeast Rrp41p. We conclude that hRrp40p, hRrp41p, and hRrp46p represent novel components of the human exosome complex
The role of comparative city policy data in assessing progress toward the urban SDG targets
As part of the UN Sustainable Development Goals, all countries have agreed toâmake cities and human set-tlements inclusive, safe, resilient and sustainableâ. We argue that there is a critical need for large-scale com-parative city policy data that, when linked with outcome data, could be used to identify where policies areworking and where they could be improved. In an assessment of the landscape of existing city policy data, basedon a comprehensive scoping review, wefind that existing databases are insufficient for the purposes of com-parative analysis. We then describe what anâidealâcity policy database would look like, where it could behoused, and how it could be developed. Such a database could be a key tool for achieving SDG 11, the urbanSustainable Development Go
Quenched growth of nanostructured lead thin films on insulating substrates
Lead island films were obtained via vacuum vapor deposition on glass and
ceramic substrates at 80 K. Electrical conductance was measured during vapor
condensation and further annealing of the film up to room temperature. The
resistance behavior during film formation and atomic force microscopy of
annealed films were used as information sources about their structure. A model
for the quenched growth, based on ballistic aggregation theory, was proposed.
The nanostructure, responsible for chemiresistive properties of thin lead films
and the mechanism of sensor response are discussed.Comment: 2 figures; accepted to Thin Solid Film
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