Lord of the Mood Rings

Our main objective is to study the mechanisms by which heat transfer taking place in the human finger will affect the color change in the mood ring. This project uses GAMBIT and FIDAP to model the heat transfer from the finger to the ring. Finding the possible range of heat generations, one can estimate the temperature range of the surface and thus the best type of LC to be used in a ring. By determining the temperature in the ring at steady state the blood flow rate can be quantified, which will provide the required heat generation to change the mood ring to any desired color. We obtained several Q?s ranging from 6800 to 7200 W/m^3 appropriate to blood flow rate, and ambient conditions with no forced convection for the model. Further sensitivity analysis was done for selected data input, such as conductivity and source term, to assess their impact on the results. It was concluded that blood flow rate corresponding to the heat generation values used ranged from 0.245 to 0.265 cm^3/min. From the results it is recommended that the color change in the LCD crystal should be most sensitive over the range of 32 to 35 ?C

Mood instability, mental illness and suicidal ideas : results from a household survey

Purpose: There is weak and inconsistent evidence that mood instability (MI) is associated with depression, post traumatic stress disorder (PTSD) and suicidality although the basis of this is unclear. Our objectives were first to test whether there is an association between depression and PTSD, and MI and secondly whether MI exerts an independent effect on suicidal thinking over and above that explained by common mental disorders. Methods: We used data from the Adult Psychiatric Morbidity Survey 2007 (N = 7,131). Chi-square tests were used to examine associations between depression and PTSD, and MI, followed by regression modelling to examine associations between MI and depression, and with PTSD. Multiple logistic regression analyses were used to assess the independent effect of MI on suicidal thinking, after adjustment for demographic factors and the effects of common mental disorder diagnoses. Results: There are high rates of MI in depression and PTSD and the presence of MI increases the odds of depression by 10.66 [95 % confidence interval (CI) 7.51–15.13] and PTSD by 8.69 (95 % CI 5.90–12.79), respectively, after adjusting for other factors. Mood instability independently explained suicidal thinking, multiplying the odds by nearly five (odds ratio 4.82; 95 % CI 3.39–6.85), and was individually by some way the most important single factor in explaining suicidal thoughts. Conclusions: MI is strongly associated with depression and PTSD. In people with common mental disorders MI is clinically significant as it acts as an additional factor exacerbating the risk of suicidal thinking. It is important to enquire about MI as part of clinical assessment and treatment studies are required

The epidemiology of bacterial vaginosis in relation to sexual behaviour

<p>Abstract</p> <p>Background</p> <p>Bacterial vaginosis (BV) has been most consistently linked to sexual behaviour, and the epidemiological profile of BV mirrors that of established sexually transmitted infections (STIs). It remains a matter of debate however whether BV pathogenesis does actually involve sexual transmission of pathogenic micro-organisms from men to women. We therefore made a critical appraisal of the literature on BV in relation to sexual behaviour.</p> <p>Discussion</p> <p><it>G. vaginalis </it>carriage and BV occurs rarely with children, but has been observed among adolescent, even sexually non-experienced girls, contradicting that sexual transmission is a necessary prerequisite to disease acquisition. <it>G. vaginalis </it>carriage is enhanced by penetrative sexual contact but also by non-penetrative digito-genital contact and oral sex, again indicating that sex <it>per se</it>, but not necessarily coital transmission is involved. Several observations also point at female-to-male rather than at male-to-female transmission of <it>G. vaginalis</it>, presumably explaining the high concordance rates of <it>G. vaginalis </it>carriage among couples. Male antibiotic treatment has not been found to protect against BV, condom use is slightly protective, whereas male circumcision might protect against BV. BV is also common among women-who-have-sex-with-women and this relates at least in part to non-coital sexual behaviours. Though male-to-female transmission cannot be ruled out, overall there is little evidence that BV acts as an STD. Rather, we suggest BV may be considered a sexually enhanced disease (SED), with frequency of intercourse being a critical factor. This may relate to two distinct pathogenetic mechanisms: (1) in case of unprotected intercourse alkalinisation of the vaginal niche enhances a shift from lactobacilli-dominated microflora to a BV-like type of microflora and (2) in case of unprotected and protected intercourse mechanical transfer of perineal enteric bacteria is enhanced by coitus. A similar mechanism of mechanical transfer may explain the consistent link between non-coital sexual acts and BV. Similar observations supporting the SED pathogenetic model have been made for vaginal candidiasis and for urinary tract infection.</p> <p>Summary</p> <p>Though male-to-female transmission cannot be ruled out, overall there is incomplete evidence that BV acts as an STI. We believe however that BV may be considered a <it>sexually enhanced disease</it>, with frequency of intercourse being a critical factor.</p

The global response: How cities and provinces around the globe tackled Covid-19 outbreaks in 2021

Background: Tackling the spread of COVID-19 remains a crucial part of ending the pandemic. Its highly contagious nature and constant evolution coupled with a relative lack of immunity make the virus difficult to control. For this, various strategies have been proposed and adopted including limiting contact, social isolation, vaccination, contact tracing, etc. However, given the heterogeneity in the enforcement of these strategies and constant fluctuations in the strictness levels of these strategies, it becomes challenging to assess the true impact of these strategies in controlling the spread of COVID-19.Methods: In the present study, we evaluated various transmission control measures that were imposed in 10 global urban cities and provinces in 2021 Bangkok, Gauteng, Ho Chi Minh City, Jakarta, London, Manila City, New Delhi, New York City, Singapore, and Tokyo.Findings: Based on our analysis, we herein propose the population-level Swiss cheese model for the failures and pit-falls in various strategies that each of these cities and provinces had. Furthermore, whilst all the evaluated cities and provinces took a different personalized approach to managing the pandemic, what remained common was dynamic enforcement and monitoring of breaches of each barrier of protection. The measures taken to reinforce the barriers were adjusted continuously based on the evolving epidemiological situation.Interpretation: How an individual city or province handled the pandemic profoundly affected and determined how the entire country handled the pandemic since the chain of transmission needs to be broken at the very grassroot level to achieve nationwide control

Formulation, stabilisation and encapsulation of bacteriophage for phage therapy

Against a backdrop of global antibiotic resistance and increasing awareness of the importance of the human microbiota, there has been resurgent interest in the potential use of bacteriophages for therapeutic purposes, known as phage therapy. A number of phage therapy phase I and II clinical trials have concluded, and shown phages don’t present significant adverse safety concerns. These clinical trials used simple phage suspensions without any formulation and phage stability was of secondary concern. Phages have a limited stability in solution, and undergo a significant drop in phage titre during processing and storage which is unacceptable if phages are to become regulated pharmaceuticals, where stable dosage and well defined pharmacokinetics and pharmacodynamics are de rigueur. Animal studies have shown that the efficacy of phage therapy outcomes depend on the phage concentration (i.e. the dose) delivered at the site of infection, and their ability to target and kill bacteria, arresting bacterial growth and clearing the infection. In addition, in vitro and animal studies have shown the importance of using phage cocktails rather than single phage preparations to achieve better therapy outcomes. The in vivo reduction of phage concentration due to interactions with host antibodies or other clearance mechanisms may necessitate repeated dosing of phages, or sustained release approaches. Modelling of phage-bacterium population dynamics reinforces these points. Surprisingly little attention has been devoted to the effect of formulation on phage therapy outcomes, given the need for phage cocktails, where each phage within a cocktail may require significantly different formulation to retain a high enough infective dose. This review firstly looks at the clinical needs and challenges (informed through a review of key animal studies evaluating phage therapy) associated with treatment of acute and chronic infections and the drivers for phage encapsulation. An important driver for formulation and encapsulation is shelf life and storage of phage to ensure reproducible dosages. Other drivers include formulation of phage for encapsulation in micro- and nanoparticles for effective delivery, encapsulation in stimuli responsive systems for triggered controlled or sustained release at the targeted site of infection. Encapsulation of phage (e.g. in liposomes) may also be used to increase the circulation time of phage for treating systemic infections, for prophylactic treatment or to treat intracellular infections. We then proceed to document approaches used in the published literature on the formulation and stabilisation of phage for storage and encapsulation of bacteriophage in micro- and nanostructured materials using freeze drying (lyophilization), spray drying, in emulsions e.g. ointments, polymeric microparticles, nanoparticles and liposomes. As phage therapy moves forward towards Phase III clinical trials, the review concludes by looking at promising new approaches for micro- and nanoencapsulation of phages and how these may address gaps in the field

Design of Plasmid Amplified DNA Building Block Synthesis System and Evaluation of Dendrimer-Like DNA Based Fluorescent Nanobarcodes

Masters ThesisMethods for producing DNA building blocks with high purity and yield were investigated, including solid-phase DNA synthesis and plasmid amplified DNA synthesis (PADS). In addition, an analysis of the properties of dendrimer-like DNA (DL-DNA) as nanobiosensor was conducted to explore the viability of its real-world application. Four-armed dsDNA building blocks (X-DNA's) were successfully acquired using solid-phase synthesis. X-DNA consisted of 4 oligonucleotides that are partially complementary such that a cross-shaped dsDNA molecule is formed upon annealing. It was ligated to a 30bp dsDNA spacer immobilized onto micrometer-sized 6% cross-linked agarose beads via biotin-avidin interactions. A subsequent washing step was performed to rid the sample of non-X-DNA structures, and X-DNA was released from the spacer by restriction enzyme digestion. Gel electrophoresis of the product showed higher purity, 72% compared to 67.5% shown in the solution-hybridized X-DNA prior to solid-phase. Characterization of X-DNA was performed by ligation of 4 complementary hairpin loops which serve to close off all open dsDNA ends and prevent the structure from exonuclease digestion. Unchanged DNA concentration after 15 and 30 min of ExoIII digestion at 37oC was observed, confirming the synthesis of X-DNA. Plasmid amplified DNA synthesis takes advantage of the natural DNA producing system in Escherichia coli for high-yield production of plasmids containing sequence for three-armed DNA building blocks (Y-DNA). A nicking enzyme was used to produce a single-stranded break in the plasmid. ExoIII digestion at 37oC was performed to produce ssDNA plasmids. Annealing at 70oC causes a branched hairpin (Y-shape) to form on each ssDNA strand. Simultaneous digestion of the Y-shape hairpin by three enzymes produces Y-DNA. Single and combinational of enzyme digestion was applied to characterize the ssDNA plasmid, and determined to be a Y-shape structure. Lastly, fluorescent DNA nanobarcodes were analyzed for their purity, coding capability, compared to concentration-based coding method, as well as differential bleaching of green (G) and red (R) fluorescence. Pure populations of DNA nanobarcodes (4G1R, 2G1R, 1G1R, 1G2R, 1G4R) and multi-code mixtures, immobilized on 5.5um polystyrene beads, were obtained. The fluorescent intensities (R and G) were measured from 12-bit images taken by a wide-field microscope; the illumination source is a Mercury arc lamp and respective fluorescent colors obtained using green and far-red filters. The purity of each population was assessed by analyzing the magnitude of R/G fluorescent ratio standard deviation for each pure barcode populations (N>50beads). Comparison of the mean for each codes to a theoretical R/G ratio yield their codability. The DNA nanobarcodes were determined to be pure and their experimental R/G ratios conform to theoretical values, unlike concentration-based DNA barcodes. Bleaching analysis of red and green fluorodyes reveal that red dye bleach faster than green, however the ratio of R/G, and nanobarcodes, did not change significantly over time