434 research outputs found
A Multi-Server Retrial Queueing Inventory System With Asynchronous Multiple Vacations
This article deals with asynchronous server vacation and customer retrial
facility in a multi-server queueing-inventory system. The Poisson process
governs the arrival of a customer. The system is comprised of c identical
servers, a finite-size waiting area, and a storage area containing S items. The
service time is distributed exponentially. If each server finds that there are
an insufficient number of customers and items in the system after the busy
period, they start a vacation. Once the servers vacation is over and it
recognizes there is no chance of getting busy, it goes into an idle state if
the number of customers or items is not sufficient, otherwise, it will take
another vacation. Furthermore, each server's vacation period occurs
independently of the other servers. The system accepts a (s, Q) control policy
for inventory replenishment. For the steady state analysis, the Marcel F Neuts
and B Madhu Rao matrix geometric approximation approach is used owing to the
structure of an infinitesimal generator matrix. The necessary stability
condition and R matrix are to be computed and presented. After calculating the
sufficient system performance measures, an expected total cost of the system is
to be constructed and numerically incorporated with the parameters.
Additionally, numerical analyses will be conducted to examine the waiting time
of customers in the queue and in orbit, as well as the expected rate of
customer loss.Comment: 43 pages, 12 figures, 5 table
Loci for primary ciliary dyskinesia map to chromosome 16p12.1-12.2 and 15q13.1-15.1 in Faroe Islands and Israeli Druze genetic isolates
SOLID DISPERSION TECHNIQUE TO ENHANCE THE SOLUBILITY AND DISSOLUTION OF FEBUXOSTAT AN BCS CLASS II DRUG
Objective: The present study was aimed to enhance the solubility of poorly water-soluble drug (BCS Class II) Febuxostat using water-soluble polymers.Methods: Pre-formulation studies like drug excipient compatibility studies by Fourier-transform infrared spectroscopyDifferential scanning calorimetry and determination of saturation solubility of drug individually in various media like distilled water and pH 7.4 phosphate buffer. Solid dispersions of Febuxostat was prepared using Polyethylene glycol (PEG 6000) (fusion method) and Polyvinyl pyrrolidone (PVP K30) (solvent evaporation method) in various ratios like 1:1, 1:2, 1:3 and 1:4 separately. The formulated solid dispersions were evaluated for percentage yield, drug content and in vitro dissolution studies.Results: From the results of pre-formulation studies it was revealed that there was no interaction between drug and excipients and the pure drug was poorly soluble in water. The percentage yield of all formulations was in the range of 54-78 %, and drug content was in the range of 43-78 mg. The solid dispersion containing polyvinylpyrrolidone K 30 in 1:4 ratio showed the highest amount of drug release at the end of 30 min than other formulations.Conclusion: Finally it was concluded that solid dispersion prepared with PVP K-30 in 1:4 ratio by solvent evaporation method was more soluble than by fusion method
Specific protease activity indicates the degree of Pseudomonas aeruginosa infection in chronic infected wounds
Chronic non-healing wounds are a major health problem with resident bacteria strongly implicated in their impaired healing. A rapid-screen to provide detailed knowledge of wound bacterial populations would therefore be of value and help prevent unnecessary and indiscriminate use of antibiotics—a process associated with promoting antibiotic resistance. We analysed chronic wound fluid samples, which had been assessed for microbial content, using 20 different fluorescent labelled peptide substrates to determine whether protease activity correlated with the bacterial load. Eight of the peptide substrates showed significant release of fluorescence after reaction with some of the wound samples. Comparison of wound fluid protease activities with the microbiological data indicated that there was no correlation between bacterial counts and enzyme activity for most of the substrates tested. However, two of the peptide substrates produced a signal corresponding with the microbial data revealing a strong positive correlation with Pseudomonas aeruginosa numbers. This demonstrated that short fluorescent labelled peptides can be used to detect protease activity in chronic wound fluid samples. The finding that two peptides were specific indicators for the presence of P. aeruginosa may be the basis for a diagnostic test to determine wound colonisation by this organism
Nerve growth factor receptor TrkA, a new receptor in insulin signaling pathway in PC12 cells
Background: TrkA is a transmembrane receptor tyrosine kinase for nerve growth factor. Results: TrkA forms a molecular complex with insulin receptor and IRS-1 to induce Akt and Erk5 phosphorylation. Conclusion: The NGF-TrkA receptor influences insulin signaling. Significance: The TrkA receptor is involved in insulin signaling, and NGF may regulate neuronal glucose uptake as neurons are insulin-insensitive. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc
Design of Smart Head-Mounted Display Technology: A convergent mixed methods study
The purpose of this study was to explore the factors impacting preference for head-mounted display (HMD) technology among individuals with visual impairment. HMD are commercially available assistive devices intended for those with low vision. Individuals with a range of visual impairment and diagnosis of either age-related macular degeneration, diabetic retinopathy, glaucoma or retinitis pigmentosa were recruited. Participants completed the Impact of Vision Impairment (IVI) questionnaire, were taught to use three different HMDs (eSight, Epson Moverio, and NuEyes) and were subsequently interviewed regarding their experience. Interviews were recorded, transcribed, and coded by two independent coders. Qualitative data was analyzed using a thematic approach and a joint display analysis was conducted. Twenty-one participants were interviewed (mean age 58.2 years, 57% male, median Snellen acuity 20/40 [range 20/20-hand movement]). An equal number of participants (n=9) expressed preference for eSight and NuEyes, while (n=3) preferred the Epson Moverio. Participants emphasized ease of use, especially of HMD controls and screen, as primary reasons for HMD preference. Participants with lower IVI Well-Being scores were more likely to express eSight preference due to clarity, ease of use, and vision improvement. Those with moderate IVI Well-Being scores were more likely to prefer the NuEyes due to appearance, wireless design, and magnification. Those with higher IVI Well-Being scores cited usability as the most important HMD feature. This study found that user preferences for HMD was associated with vision-related well-being, and that usability of devices was paramount in preference
The Exomars Climate Sounder (EMCS) Investigation
The ExoMars Climate Sounder (EMCS) investigation is developed at the Jet Propulsion Laboratory (Principal Investigator J. T. Schofield) in collaboration with an international scientific team from France, the United Kingdom and the USA.
EMCS plans to map daily, global, pole-to-pole profiles of temperature, dust, water and CO2 ices, and water vapor from the proposed 2016 ExoMars Trace Gas Orbiter (EMTGO). These profiles are to be assimilated into Mars General Circulation Models (MGCMs) to generate global, interpolated fields of measured and derived parameters such as wind
Factors associated with recovery from 1 minute Apgar score <4 in live, singleton, term births: an analysis of Malaysian National Obstetrics Registry data 2010–2012
Daniel Reidpath - ORCID: 0000-0002-8796-0420
https://orcid.org/0000-0002-8796-0420The neonatal Apgar score at 5 min has been found to be a better predictor of outcomes than the Apgar score at 1 min. A baby, however, must pass through the first minute of life to reach the fifth. There has been no research looking at predictors of recovery (Apgar scores ≥7) by 5 min in neonates with 1 min Apgar scores <4.
Methods
An analysis of observational data was conducted using live, singleton, term births recorded in the Malaysian National Obstetrics Registry between 2010 and 2012. A total of 272,472 live, singleton, term births without congential anomalies were recorded, of which 1,580 (0.59%) had 1 min Apgar scores <4. Descriptive methods and bi- and multi-variable logistic regression were used to identify risk factors associated with recovery (5 min Apgar score ≥7) from 1 min Apgar scores <4.
Results
Less than 1% of births have a 1 min Apgar scores <4. Only 29.4% of neonates with 1 min Apgar scores <4 recover to a 5 min Apgar score ≥7. Among uncomplicated vaginal deliveries, after controlling for other factors, deliveries by a doctor of neonates with a 1 min Apgar score <4 had odds of recovery 2.4 times greater than deliveries of neonates with a 1 min Apgar score <4 by a nurse-midwife. Among deliveries of neonates with a 1 min Apgar score <4 by doctors, after controlling for other factors, planned and unplanned CS was associated with better odds of recovery than uncomplicated vaginal deliveries. Recovery was also associated with maternal obesity, and there was some ethnic variation – in the adjusted analysis indigenous (Orang Asal) Malaysians had lower odds of recovery.
Conclusions
A 1 min Apgar score <4 is relatively rare, and less than a third recover by five minutes. In those newborns the qualification of the person performing the delivery and the type of delivery are independent predictors of recovery as is maternal BMI and ethnicity. These are associations only, not necessarily causes, and they point to potential areas of research into health systems factors in the labour room, as well as possible biological and cultural factors.https://doi.org/10.1186/s12884-017-1293-917pubpub
Factors associated with recovery from 1 minute Apgar score <4 in live, singleton, term births: an analysis of Malaysian National Obstetrics Registry data 2010–2012
Daniel Reidpath - ORCID: 0000-0002-8796-0420
https://orcid.org/0000-0002-8796-0420The neonatal Apgar score at 5 min has been found to be a better predictor of outcomes than the Apgar score at 1 min. A baby, however, must pass through the first minute of life to reach the fifth. There has been no research looking at predictors of recovery (Apgar scores ≥7) by 5 min in neonates with 1 min Apgar scores <4.
Methods
An analysis of observational data was conducted using live, singleton, term births recorded in the Malaysian National Obstetrics Registry between 2010 and 2012. A total of 272,472 live, singleton, term births without congential anomalies were recorded, of which 1,580 (0.59%) had 1 min Apgar scores <4. Descriptive methods and bi- and multi-variable logistic regression were used to identify risk factors associated with recovery (5 min Apgar score ≥7) from 1 min Apgar scores <4.
Results
Less than 1% of births have a 1 min Apgar scores <4. Only 29.4% of neonates with 1 min Apgar scores <4 recover to a 5 min Apgar score ≥7. Among uncomplicated vaginal deliveries, after controlling for other factors, deliveries by a doctor of neonates with a 1 min Apgar score <4 had odds of recovery 2.4 times greater than deliveries of neonates with a 1 min Apgar score <4 by a nurse-midwife. Among deliveries of neonates with a 1 min Apgar score <4 by doctors, after controlling for other factors, planned and unplanned CS was associated with better odds of recovery than uncomplicated vaginal deliveries. Recovery was also associated with maternal obesity, and there was some ethnic variation – in the adjusted analysis indigenous (Orang Asal) Malaysians had lower odds of recovery.
Conclusions
A 1 min Apgar score <4 is relatively rare, and less than a third recover by five minutes. In those newborns the qualification of the person performing the delivery and the type of delivery are independent predictors of recovery as is maternal BMI and ethnicity. These are associations only, not necessarily causes, and they point to potential areas of research into health systems factors in the labour room, as well as possible biological and cultural factors.https://doi.org/10.1186/s12884-017-1293-917pubpub
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