Antimicrobial thin films via aerosol assisted chemical vapour deposition

This thesis focuses on the development of antimicrobial coatings through the use of aerosol assisted chemical vapour deposition (AACVD). The spread of nosocomial infections in healthcare settings can be attributed to contact between healthcare personnel and infected patients. Consequently, it can be proposed that the utilisation of antimicrobial surfaces may cause a decrease in hospital microbial contamination as well as enhancing infection-control. Aerosol assisted chemical vapour deposition (AACVD) is used as the main deposition technique. It involves the formation of an aerosol through the dissolution of a precursor in a solvent and depends on solubility rather than the volatility of the precursors. A major advantage for AACVD is the ability to be an industrially scalable process and to deposit on a wide range of substrates including the commonly used materials on touch surfaces in hospitals such as stainless steel. This is an approach that offers a fast and easy route to the deposition of nanocomposite thin films. Recently, much research has been invested into the preparation of these thin films, particularly for applications in antimicrobial coatings on surfaces. Moreover, it has been noted that the doping of metal oxide thin films with natural antimicrobial species can increase the antibacterial effectiveness. During the course of this research project, the development of nanocomposite films based on copper, copper oxide, gallium oxide and zinc oxide was explored, with the aim of forming robust stable films with antimicrobial efficacy. The effectiveness of the antimicrobial films was investigated under lighting conditions found in hospital environments using serial dilution and viable colony counts. All experiments were carried out in duplicate and the number of survivors were determined by visible counting. Due to the high antimicrobial activity exhibited for copper, incorporating copper into metal oxides (gallium oxide and zinc oxide) were investigated in order to produce transparent films that will increased bactericidal activity. The investigation examined the precursor delivery, effect of substrate temperature, solvent and additives on the CVD reactions. All of the films that were prepared were characterised using a number of techniques such as SEM/EDX, XRD, UV/Visible spectroscopy, XPS and XAS

Competency-based Learning: The effectiveness of targeted resident education and clinical auditing feedback on completed death certificate accuracy rates

Background: Death certification is an integral part of physician practice, yet common errors are being encountered from this vital source of health information. Most medical training programs lack formal curricula for this important skill. Accurate information from DC will help in improve our mortality data which can be use public health purposesObjectives: This study evaluated the effect of a multifaceted educational intervention on accuracy of completing death certification in a tertiary-based paediatric residency programMethod: A pre-post intervention and control cohort study over 12- month period to assess the effect of our multifaceted intervention accuracy rate of completed DC was conducted. The intervention consisted of a 3-part program (distribution of educational material, presentation by a skilled instructor, skills workshop, and clinical mortality/auditing feedback sessions). Primary outcome was the difference in scores preand post-intervention and also the rate of accuracy on the MAHI death certificate scoring system.Results: The mean score before the intervention was 6.8±2.7 and 7.1±2.3 in both the intervention and control cohorts respectively. The mean score after the intervention was 16.3±2.5 and 7.3±2.8 in both the intervention and control cohorts respectively indicating an increase in scores. The mean difference in pre- and post-tutorial scores was significant (t=20.39, p=0.0001).Conclusions: We found that using a multifaceted educational intervention to train junior physicians on how to correctly complete a DC was effective in a residency-based pediatric programKeywords: Death certificate, medical education, multifaceted training, heath information, Nigeria

Genotypic Characterization of Fungal Species Isolated From Broiler Breeder Chickens, Dead-In-Shell and Hatched Chicks

To investigate the prevalence of fungal agents in local Egyptian broiler breeder chicken’s premises, tracheal and cloacal swabs from chickens, feed, and water samples were collected. The targeted breed's dead-in-shell eggs and newly hatched chick’s samples were also tested. All fungal isolates were morphologically typed and the predominant fungal species were further subjected to molecular typing using PCR-RFLP and gene sequence analysis of the β-tubulin gene. Results revealed a high prevalence of fungal isolates in tracheal and cloacal swabs (39.3 - 48.1%) and feed and water samples (37.5% and 28.6%, respectively). Fungal isolation rates in dead-in-shell eggs of all breeds were high except in Dahaby breed. Aspergillus species including A. niger, A. flavus, and A. terreus were the predominantly isolated fungi from all collected samples. The ß-Tubulin genes PCR-RFLP of selected Aspergillus isolates showed a characteristic restriction pattern for each species; however, the method was unable to distinguish between strains. The β-tubulin gene phylogenetic and sequence analysis of selected A. flavus, and A. terreus from breeder chickens and their hatching chicks indicated their relatedness to isolates from bronchopulmonary Aspergillosis in humans in the Middle East. In conclusion, the Aspergillus species remains the most prevalent fungi in breeder chickens, their incubated eggs and hatched chicks indicating their widespread in hatcheries. The PCR-RFLP is an easy tool to discriminate between Aspergilli species, however, the β-tubulin sequence analysis more descriptive of potential sources of fungal contamination. Further epidemiological studies are needed to monitor avian and human Aspergilli in poultry houses with a special focus on antifungal drug-resistant strains

An analytic approximation to the Diffusion Coefficient for the periodic Lorentz Gas

An approximate stochastic model for the topological dynamics of the periodic triangular Lorentz gas is constructed. The model, together with an extremum principle, is used to find a closed form approximation to the diffusion coefficient as a function of the lattice spacing. This approximation is superior to the popular Machta and Zwanzig result and agrees well with a range of numerical estimates.Comment: 13 pages, 4 figure

Essential oils from the leaves of six medicinal palnts of Nigeria

The chemistry of Cassia siamea L., C. occidentalis L. (Fabaceae), Cnestis ferruginea Vahl ex DC (Connaraceae), Anthocleista djalonensis A. Chev (Loganiaceae), Solanum torvum Swartz and S. erianthum G. Don (Solanaceae) volatiles grown in Nigeria have been studied. The essential oils were obtained by hydrodistillation and analyzed by GC and GC-MS. The main compounds of C. siamea were (E)-geranyl acetone (5.8%), 1-octen-3-ol (5.8%), linalool (7.8%), iso-italicene (15.4%) and (E)-β-damascenone (11.0%). On the other hand, C. occidentalis consisted mainly of (E)-geranyl acetone (8.0%), hexahydrofarnesylacetone (24.0%) and (E)-phytol acetate (40.7%). The oil of C. ferruginea was comprised mainly of (E)-geranyl acetone (13.7%), (E)-α-ionone (9.5%), phytol (5.8%), pentadecanal (6.1%) and 1-octen-3-ol (5.5%). The main compounds of A. djalonensis were α-humulene (31.9%), β-caryophyllene (17.8%), humulene epoxide II (12.7%) and caryophyllene oxide (5.9%). The main volatiles of S. torvum were (E)-phytol acetate (38.7%), pentadecanal (25.3%) and (E)-geranyl acetone (5.0%). Apart from methyl salicylate (4.5%), tetradecanal (2.2%), 2-pentyl furan (1.8%), hexahydrofarnesylacetone (1.6%) and hexadecanal (1.1%), all other compounds were either present in trace quantity or in amounts less than 1%. On the other hand, α-humulene (46.6%) and β-caryophyllene (20.6%) were the compounds occurring in higher quantities in S. erianthum. The volatile oil contents of Cassia siamea, Cnestis ferruginea, Anthocleista djalonensis and Solanum torvum are being reported for the first tim

Symptoms predicting remission after divalproex augmentation with olanzapine in partially nonresponsive patients experiencing mixed bipolar I episode: a post-hoc analysis of a randomized controlled study

<p>Abstract</p> <p>Background</p> <p>Rating scale items in a 6-week clinical trial of olanzapine versus placebo augmentation in patients with mixed bipolar disorder partially nonresponsive to ≥14 days of divalproex monotherapy were analyzed to characterize symptom patterns that could predict remission. At baseline, the two treatment groups were similar.</p> <p>Findings</p> <p>Factor analysis with Varimax rotation was performed <it>post hoc </it>on baseline items of the 21-Item Hamilton Depression Rating Scale (HDRS-21) and Young Mania Rating Scale (YMRS). Backwards-elimination logistic regression ascertained factors predictive of protocol-defined endpoint remission (HDRS-21 score ≤ 8 and YMRS score ≤ 12) with subsequent determination of optimally predictive factor score cutoffs.</p> <p>Factors for Psychomotor activity (YMRS items for elevated mood, increased motor activity, and increased speech and HDRS-21 agitation item) and Guilt/Suicidality (HDRS-21 items for guilt and suicidality) significantly predicted endpoint remission in the divalproex+olanzapine group. No factor predicted remission in the divalproex+placebo group. Patients in the divalproex+olanzapine group with high pre-augmentation psychomotor activity (scores ≥10) were more likely to remit compared to those with lower psychomotor activity (odds ratio [OR] = 3.09, 95% confidence interval [CI] = 1.22-7.79), and patients with marginally high Guilt/Suicidality (scores ≥2) were less likely to remit than those with lower scores (OR = 0.37, 95% CI = 0.13-1.03). Remission rates for divalproex+placebo vs. divalproex+olanzapine patients with high psychomotor activity scores were 22% vs. 45% (p = 0.08) and 33% vs. 48% (p = 0.29) for patients with low Guilt/Suicidality scores.</p> <p>Conclusions</p> <p>Patients who were partially nonresponsive to divalproex treatment with remaining high vs. low psychomotor activity levels or minimal vs. greater guilt/suicidality symptoms were more likely to remit with olanzapine augmentation.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov; <url>http://clinicaltrials.gov/ct2/show/NCT00402324?term=NCT00402324&rank=1</url>, Identifier: NCT00402324</p

Seed Germination Strategies of Mediterranean Halophytes Under Saline Condition

The study of the ecological strategies adopted by seed plants to ensure their success in different environments is closely related to germination ecology. This implies a careful knowledge of ecophysiology of seeds and, therefore, also of interaction between plants and the complexity of external factors. In particular, the environmental conditions of the area where a plant grows and produces seeds represent the main factors that influence successful seedling establishment. The physical-chemical features of habitats, and therefore their heterogeneity, affect the behavior of seeds in different ways. In addition to the timing of seed production, they can induce or terminate dormancy and/or germination and influence the germination pattern of different seeds in the same plant and so the composition and dispersal of soil seed banks. Salinity is a major abiotic stress affecting growth and plant productivity worldwide, constituting one of the main topics of study in the field of plant physiology. Halophytes are the plants that have the availability to survive and develop in different types of saline habitats. In this chapter, we consider some examples to illustrate the main adaptive strategies used by the seeds of halophytes on ecophysiological perspectives to survive in habitats affected by high levels of salinity. The focus is on the species that live in the brackish or salt coastal areas of the Mediterranean Basin. On these environments, the salt stress may act synergistically with intense anthropic pressure, generating profound alterations in the ecosystem and threatening the survival of the plant species very sensitive to the effects of climate change also. The results show the main diverse strategies, such as dormancy cycling, seed heteromorphism, and recovery capacity, from saline shock, favoring the chances of seed survival. The interaction between temperature and salinity during germination was also discussed assessing its crucial role as an ecological strategy

Maternal BMI and nutritional status in early pregnancy and its impact on neonatal outcomes at birth in Bangladesh

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background To assess the maternal characteristics and nutritional status according to body mass index (BMI) at 6–14 weeks of gestation and to examine the relationship between maternal nutritional status in early pregnancy and its impact on neonatal birth weight. Methods The investigation was conducted from April 2011 to June 2012 in Dhaka, Bangladesh. A total of 498 primigravida pregnant women participated in the study; women with known diabetes or previous gestational diabetes (GDM) were excluded. Maternal demographic details, pregnancy history and anthropometric measurements were obtained from the mother at the recruitment (6–14 weeks), 2nd visit between 24 and 28 week of gestation and 3rd visit at delivery. Cord venous blood samples of newborns (n = 138) were collected immediately after delivery for blood glucose, insulin, lipid profile, leptin and micronutrients including serum folate, ferritin, homocysteine, vitamin D, and vitamin B12. Results The prevalence at 6–14 weeks of pregnancy of anemia (Hb,  15 μmol/l), folate deficiency (< 3 ng/ml) and iron deficiency (ferritin < 13 ng/ml) were 19.5, 46.4, 15.1, 1.2, 0.4, and 12.7% respectively. GDM was found in 18.4% women. The prevalence of GDM was higher in overweight women (28.1%) than underweight (16.7%) and normal weight women (16.0%: p <  0.05). The incidence of low birth weight (LBW) and preterm delivery were 11.6 and 5.8% respectively and was not related to maternal BMI at 6–14 weeks of pregnancy. Maternal height was positively (p = 0.02), and homocysteine was negatively associated with neonatal birth weight (p = 0.02). In addition, the newborn’s cord serum folate was positively (p = 0.03) and cord triglyceride was negatively (p = 0.03) associated with neonatal birth weight. Conclusion Multiple maternal micronutrient deficiencies were present in early pregnancy. Maternal BMI in early pregnancy was not related to preterm deliveries or LBW. LBW was associated with lower folate, elevated cord triglyceride concentrations of the neonates and mother’s height and increase in maternal homocysteine levels. The data has important implications for pregnancy care in Bangladesh and other similar communities.Financial support from European Union (FP7 EU grant: 83599025)

Double field theory of type II strings

We use double field theory to give a unified description of the low energy limits of type IIA and type IIB superstrings. The Ramond-Ramond potentials fit into spinor representations of the duality group O(D, D) and field-strengths are obtained by acting with the Dirac operator on the potentials. The action, supplemented by a Spin+ (D, D)-covariant self-duality condition on field strengths, reduces to the IIA and IIB theories in different frames. As usual, the NS-NS gravitational variables are described through the generalized metric. Our work suggests that the fundamental gravitational variable is a hermitian element of the group Spin(D, D) whose natural projection to O(D, D) gives the generalized metric.United States. Dept. of Energy (cooperative research agreement DE-FG02-05ER41360)