Research on the Implementation of VoIP Service in Mobile Ad-hoc Network

Traditional way to implement VoIP application on hard-wired network is based on the fixed and invariable IP addresses of the source and destination nodes. However, in Mobile Ad-hoc Network (MANET), the IP address of each node is auto-configured and may change at any time. Therefore, the traditional way cannot be applied on MANET. This paper presents a new way to design VoIP application on Mobile Ad-hoc Network, which can correctly solve the problem of variable IP addresses in MANET and make the nodes communicate with each other reliably

Preliminary study on assimilation of significant wave heights from T/P altimeter

2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Desorption characteristics of H₂O and CO₂ from alumina F200 under different feed/purge pressure ratios and regeneration temperatures

Air pre-purification is an important process for industrial air separation with cryogenic distillation method. This process is typically realized by pressure swing adsorption or temperature swing adsorption. H₂O and CO₂ are the two major components to be removed among the contaminants. In this paper, we establish a mathematical model describing the mass and heat balances in the adsorption bed, and the double-component adsorption/desorption equilibriums of H₂O/CO₂ on alumina F200. To conduct desorption performance analysis, a one-cycle process consisting of feed, blowdown, and purge step under different operating conditions, such as feed/purge pressure ratio and regeneration temperature, is numerically studied. The effect of heat on the desorption performance of H₂O and CO₂ is investigated by changing the purge gas temperature within 30–200 °C under feed/purge pressure ratios of 6:1.1 and 10:1.1, respectively. Detailed results of the H₂O and CO₂ adsorption/desorption behaviors in the bed are demonstrated. The mass and heat transfer characteristics during desorption are also analyzed. Suggestions on the optimization of the heating temperature and duration of purge gas are also proposed

Developmental mechanism underlying sensorimotor control of orienting behavior

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Comparison of primary care experiences among adults in general outpatient clinics and private general practice clinics in Hong Kong

Abstract. Background. The main goal of Hong Kong's publicly-funded general outpatient clinics (GOPCs) is to provide primary medical services for the financially vulnerable. The objective of the current study was to compare the primary care experiences of GOPC users and the users of care provided by private general practitioners (GPs) in Hong Kong via a territory-wide telephone survey. Methods. One thousand adults in Hong Kong aged 18 and above were interviewed by a telephone survey. The modified Chinese translated Primary Care Assessment Tool was used to collect data on respondents' primary care experience. Results. Our results indicated that services provided by GOPC were more often used by female, older, poorer, chronically-ill and less educated population. GOPC participants were also more likely to have visited a specialist or used specialist services (69.7% vs. 52.0%; p < 0.001), although this difference in utilization of specialist services disappeared after adjusting for age (55.7% vs. 52.0%, p = 0.198). Analyses were also performed to asses the relationship between healthcare settings (GOPCs versus private GPs) and primary care quality. Private GP patients achieved higher overall PCAT scores largely due to better accessibility (Mean: 6.88 vs. 8.41, p < 0.001) and person-focused care (Mean: 8.37 vs. 11.69, p < 0.001). Conclusions. Our results showed that patients primarily receiving care from private GPs in Hong Kong reported better primary care experiences than those primarily receiving care from GOPCs. This was largely due to the greater accessibility and better interpersonal relationships offered by the private GPs. As most patients use both GOPCs and private GPs, their overall primary care experiences may not be as different as the findings of this study imply. © 2010 Wong et al; licensee BioMed Central Ltd.link_to_subscribed_fulltex

Myoclonic status epilepticus and cerebellar hypoplasia associated with a novel variant in the GRIA3 gene

AMPA-type glutamate receptors (AMPARs) are postsynaptic ionotropic receptors which mediate fast excitatory currents. AMPARs have a heterotetrameric structure, variably composed by the four subunits GluA1-4 which are encoded by genes GRIA1-4. Increasing evidence support the role of pathogenic variants in GRIA1-4 genes as causative for syndromic intellectual disability (ID). We report an Italian pedigree where some male individuals share ID, seizures and facial dysmorphisms. The index subject was referred for severe ID, myoclonic seizures, cerebellar signs and short stature. Whole exome sequencing identified a novel variant in GRIA3, c.2360A > G, p.(Glu787Gly). The GRIA3 gene maps to chromosome Xq25 and the c.2360A > G variant was transmitted by his healthy mother. Subsequent analysis in the family showed a segregation pattern compatible with the causative role of this variant, further supported by preliminary functional insights. We provide a detailed description of the clinical evolution of the index subjects and stress the relevance of myoclonic seizures and cerebellar syndrome as cardinal features of his presentation

CRISPR-Cas9 screens in human cells and primary neurons identify modifiers of C9ORF72 dipeptide-repeat-protein toxicity.

Hexanucleotide-repeat expansions in the C9ORF72 gene are the most common cause of amyotrophic lateral sclerosis and frontotemporal dementia (c9ALS/FTD). The nucleotide-repeat expansions are translated into dipeptide-repeat (DPR) proteins, which are aggregation prone and may contribute to neurodegeneration. We used the CRISPR-Cas9 system to perform genome-wide gene-knockout screens for suppressors and enhancers of C9ORF72 DPR toxicity in human cells. We validated hits by performing secondary CRISPR-Cas9 screens in primary mouse neurons. We uncovered potent modifiers of DPR toxicity whose gene products function in nucleocytoplasmic transport, the endoplasmic reticulum (ER), proteasome, RNA-processing pathways, and chromatin modification. One modifier, TMX2, modulated the ER-stress signature elicited by C9ORF72 DPRs in neurons and improved survival of human induced motor neurons from patients with C9ORF72 ALS. Together, our results demonstrate the promise of CRISPR-Cas9 screens in defining mechanisms of neurodegenerative diseases

Lysine-Specific Demethylase 1 (LSD1) Is Required for the Transcriptional Repression of the Telomerase Reverse Transcriptase (hTERT) Gene

BACKGROUND: Lysine-specific demethylase 1 (LSD1), catalysing demethylation of mono- and di-methylated histone H3-K4 or K9, exhibits diverse transcriptional activities by mediating chromatin reconfiguration. The telomerase reverse transcriptase (hTERT) gene, encoding an essential component for telomerase activity that is involved in cellular immortalization and transformation, is silent in most normal human cells while activated in up to 90% of human cancers. It remains to be defined how exactly the transcriptional activation of the hTERT gene occurs during the oncogenic process. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we determined the effect of LSD1 on hTERT transcription. In normal human fibroblasts with a tight hTERT repression, a pharmacological inhibition of LSD1 led to a weak hTERT expression, and a robust induction of hTERT mRNA was observed when LSD1 and histone deacetylases (HDACs) were both inhibited. Small interference RNA-mediated depletion of both LSD1 and CoREST, a co-repressor in HDAC-containing complexes, synergistically activated hTERT transcription. In cancer cells, inhibition of LSD1 activity or knocking-down of its expression led to significant increases in levels of hTERT mRNA and telomerase activity. Chromatin immunoprecipitation assay showed that LSD1 occupied the hTERT proximal promoter, and its depletion resulted in elevated di-methylation of histone H3-K4 accompanied by increased H3 acetylation locally in cancer cells. Moreover, during the differentiation of leukemic HL60 cells, the decreased hTERT expression was accompanied by the LSD1 recruitment to the hTERT promoter. CONCLUSIONS/SIGNIFICANCE: LSD1 represses hTERT transcription via demethylating H3-K4 in normal and cancerous cells, and together with HDACs, participates in the establishment of a stable repression state of the hTERT gene in normal or differentiated malignant cells. The findings contribute to better understandings of hTERT/telomerase regulation, which may be implicated in the development of therapeutic strategies for telomerase dysregulation-associated human diseases including cancers

Facility type and primary care performance in sub-district health promotion hospitals in Northern Thailand

This paper examines primary care performance in three types of community health facilities in five provinces in northern Thailand. Tambon (sub-district) health promotion hospitals (THPHs) were introduced in 2009 to upgrade the services offered by the previous health centres, but were hampered by shortages of trained doctors and nurses. The Ministry of Public Health (MoPH) designated three categories of THPH, defined according to whether they were regularly staffed by a medical practitioner, a qualified nurse or non-clinical public health officers. While the plan is to move over time to doctor-staffed THPHs, many rural areas rely on facilities staffed by public health officers or nurses. The study used structured interviews to measure patient views on performance, defined in terms of accessibility, continuity, comprehensiveness, co-ordination and community orientation, in 23 THPHs divided across the three types. Counter-intuitively it was the THPHs staffed by public health officers which achieved the highest scores, followed by nurse-staffed facilities and then doctor-staffed facilities. The sharpest differences found were in the scores for accessibility, continuity, and comprehensiveness of care. The authors argue that these are associated with local services, which rural patients in particular value more than services offered by doctors on rotation in larger outpatient department-like centres. Patients value these aspects of care more than professional skill-mix per se. This is not an argument for delaying an increase in use of qualified staff, but an indication of the need to do this in a way that preserves the features of local services that patients value

BRE modulates granulosa cell death to affect ovarian follicle development and atresia in the mouse

The BRE (brain and reproductive expression) gene, highly expressed in nervous and reproductive system organs, plays an important role in modulating DNA damage repair under stress response and pathological conditions. Folliculogenesis, a process that ovarian follicle develops into maturation, is closely associated with the interaction between somatic granulosa cell and oocyte. However, the regulatory role of BRE in follicular development remains undetermined. In this context, we found that BRE is normally expressed in the oocytes and granulosa cells from the primordial follicle stage. There was a reduction in follicles number of BRE mutant (BRE(−/−)) mice. It was attributed to increase the follicular atresia in ovaries, as a result of retarded follicular development. We established that cell proliferation was inhibited, while apoptosis was markedly increased in the granulosa cells in the absence of BRE. In addition, expressions of γ-H2AX (marker for showing DNA double-strand breaks) and DNA damage-relevant genes are both upregulated in BRE(−/−) mice. In sum, these results suggest that the absence of BRE, deficiency in DNA damage repair, causes increased apoptosis in granulosa cells, which in turn induces follicular atresia in BRE(−/−) mice