Supporting youth mental health with arts-based strategies: a global perspective.

The devastating impact of youth mental health concerns is increasingly evident on a global scale. This crisis calls for innovative solutions that are sufficiently accessible, scalable, and cost-effective to support diverse communities around the world. One such solution involves engagement in the arts: incorporating and building upon existing local resources and cultural practices to bolster youth mental health. In this article, we describe the global youth mental health crisis and note major gaps in the knowledge and resources needed to address it. We then discuss the potential for arts- and culture-based strategies to help meet this challenge, review the mounting evidence regarding art's ability to support mental health, and call for action to undertake critical research and its translation into accessible community practices. Four steps are suggested: (1) elevate and prioritize youth voice, (2) develop core outcome measures, (3) identify and analyze successful models around the globe, and (4) generate clear funding pathways for research and translational efforts. Worldwide implementation of arts- and culture-based strategies to address youth mental health will provide critical resources to support the health, wellbeing and flourishing of countless youth across the globe.

Skin squames contribute to ammonia and volatile fatty acid production from bacteria colonizing in air-cooling units with odor complaints.

One of the most notable Indoor Air Quality problems is odor emission. This study investigated the potential contribution of skin squames to the production of ammonia (NH3 ) and volatile organic acids (VFAs) by 7 bacteria isolated from air-cooling (AC) units with complaints of urine and body odors. Our previous study showed that keratinolytic activity is higher in AC units with odor complaints than those without. In the offices where these units are located, the most likely source of keratins is from human skin squames. Most bacteria can produce NH3 and VFAs in the skin squame culture. Some correlations between the levels of NH3 , NH4+, VFAs, and keratinolytic activity were found. The odor production pathway with skin squames was proposed. Staphylococcus haemolyticus was abundant in the AC units with odor problems and had a high level of keratinolytic activity in addition to odor production. For long-term odor control, it is important to reduce the level of skin squames entering the AC units.

Spontaneous resolution of acute rejection and tolerance induction with IL-2 fusion protein in vascularized composite allotransplantation.

Vascularized composite allotransplantation (VCA) has emerged as a treatment option for treating nonlife-threatening conditions. Therefore, in order to make VCA a safe reconstruction option, there is a need to minimize immunosuppression, develop tolerance-inducing strategies and elucidate the mechanisms of VCA rejection and tolerance. In this study we explored the effects of hIL-2/Fc (a long-lasting human IL-2 fusion protein), in combination with antilymphocyte serum (ALS) and short-term cyclosporine A (CsA), on graft survival, regulatory T cell (Treg) proliferation and tolerance induction in a rat hind-limb transplant model. We demonstrate that hIL-2/Fc therapy tips the immune balance, increasing Treg proliferation and suppressing effector T cells, and permits VCA tolerance as demonstrated by long-term allograft survival and donor-antigen acceptance. Moreover, we observe two distinct types of acute rejection (AR), progressive and reversible, within hIL-2/Fc plus ALS and CsA treated recipients. Our study shows differential gene expression profiles of FoxP3 versus GzmB, Prf1 or interferon-γ in these two types of AR, with reversible rejection demonstrating higher Treg to Teff gene expression. This correlation of gene expression profile at the first clinical sign of AR with VCA outcomes can provide the basis for further inquiry into the mechanistic aspects of VCA rejection and future drug targets.

Direct incorporation of the NKT-cell activator α-galactosylceramide into a recombinant Listeria monocytogenes improves breast cancer vaccine efficacy.

BACKGROUND: Immune suppression in the tumour microenvironment remains a major limitation to successful immunotherapy of cancer. In the current study, we analysed whether the natural killer T cell-activating glycolipid α-galactosylceramide could overcome immune suppression and improve vaccination against metastatic breast cancer. METHODS: Mice with metastatic breast cancer (4T1 model) were therapeutically treated with a Listeria monocytogenes-based vaccine expressing tumour-associated antigen Mage-b followed by α-galactosylceramide as separate agents, or as a complex of α-galactosylceramide stably incorporated into Listeria-Mage-b. Effects on metastases, tumour weight, toxicity and immune responses were determined. RESULTS: Sequential treatments of mice with established 4T1 breast carcinomas using Listeria-Mage-b followed by α-galactosylceramide as a separate agent was highly effective at reducing metastases, but was accompanied by severe liver toxicity. In contrast, combined therapy using Listeria-Mage-b modified by incorporation of α-galactosylceramide resulted in nearly complete elimination of metastases without toxicity. This was associated with a significant increase in the percentage of natural killer T cells in the spleen, and an increase in natural killer cell activity and in T cell responses to Mage-b. CONCLUSIONS: Our results suggest that direct incorporation of α-galactosylceramide into a live bacterial vaccine vector is a promising non-toxic new approach for the treatment of metastatic breast cancer.

Atorvastatin plus omega-3 fatty acid ethyl ester decreases very-low-density lipoprotein triglyceride production in insulin resistant obese men.

AIM: To test the effect of atorvastatin (ATV) and ATV plus ω-3 FAEEs on VLDL-TG metabolism in obese, insulin resistant men. METHODS: We carried out a 6-week randomized, placebo-controlled study to examine the effect of ATV (40 mg/day) and ATV plus ω-3 FAEEs (4 g/day) on VLDL-TG metabolism in 36 insulin resistant obese men. VLDL-TG kinetics were determined using d5 -glycerol, gas chromatography-mass spectrometry and compartmental modelling. RESULTS: Compared with the placebo, ATV significantly decreased VLDL-TG concentration (-40%, p < 0.001) by increasing VLDL-TG fractional catabolic rate (FCR) (+47%, p < 0.01). ATV plus ω-3 FAEEs lowered VLDL-TG concentration to a greater degree compared with placebo (-46%, p < 0.001) or ATV monotherapy (-13%, p = 0.04). This was achieved by a reduction in VLDL-TG production rate (PR) compared with placebo (-32%, p = 0.008) or ATV (-20%, p = 0.03) as well as a reciprocal increase in VLDL-TG FCR (+42%, p < 0.05) compared with placebo. CONCLUSION: In insulin resistant, dyslipidaemic, obese men, ATV improves VLDL-TG metabolism by increasing VLDL-TG FCR. The addition of 4 g/day ω-3 FAEE to statin therapy provides further TG-lowering by lowering VLDL-TG PR.

Vascularized osteomyocutaneous allografts are permissive to tolerance by induction-based immunomodulatory therapy.

Vascularized composite allografts (VCAs) are unique among transplanted organs in that they are composed of multiple tissues with disparate antigenic and immunologic properties. As the predominant indications for VCAs are non-life-threatening conditions, there is an immediate need to develop tolerance induction strategies and to elucidate the mechanisms of VCA rejection and tolerance using VCA-specific animal models. In this study, we explore the effects of in vitro induced donor antigen-specific CD4(-) CD8(-) double negative (DN) Treg-based therapy, in a fully MHC mismatched mouse VCA such as a vascularized osteomyocutaneous as compared to a non-VCA such as a full thickness skin (FTS) transplantation model to elucidate the unique features of VCA rejection and tolerance. We demonstrate that combined therapy with antigen-induced CD4 derived DN Tregs and a short course of anti-lymphocyte serum, rapamycin and IL-2/Fc fusion protein results in donor-specific tolerance to VCA, but not FTS allografts. Macrochimerism was detected in VCA but not FTS allograft recipients up to >60 days after transplantation. Moreover, a significant increase of CD4(+) Foxp3(+) Tregs was found in the peripheral blood of tolerant VCA recipients. These data suggest that VCA are permissive to tolerance induced by DN Treg-based induction therapy.

Monsoon and primary acute angle closure in malaysia.

INTRODUCTION: Acute angle closure (AAC) without prompt treatment may lead to optic neuropathy. Environmental factor such as climate change may precipitate pupillary block, the possible mechanism of AAC. OBJECTIVE: To determine the association of northeast monsoon and incidence of AAC in Malaysia. MATERIALS AND METHODS: A retrospective study was conducted on AAC patients admitted to two main tertiary hospitals in Kelantan, Malaysia between January 2001 and December 2011. The cumulative number of rainy day, amount of rain, mean cloud cover and 24 hours mean humidity at the estimated day of attack were obtained from the Department of Meteorology, Malaysia. RESULTS: A total 73 cases of AAC were admitted with mean duration of 4.1SD 2.0 days. More than half have previous history of possibility of AAC. There was higher incidence of AAC during the northeast monsoon (October to March). There was also significant correlation of number of rainy day (r=0.718, p<0.001), amount of rain (r=0.587, p<0.001), cloud cover (r=0.637, p<0.001), mean daily global radiation (r=- 0.596, P<0.001), 24 hours mean temperature (r=-0.298, p=0.015) and 24 hours mean humidity (r=0.508, p<0.001) with cumulative number of admission for AAC for 12 calendar months. CONCLUSION: Higher incidence of AAC during northeast monsoon suggested the effect of climate as the potential risk factor. Prompt treatment to arrest pupillary block and reduction of the intraocular pressure is important to prevent potential glaucomatous damage. Public awareness of AAC and accessibility to treatment should be part of preparation to face the effect of northeast monsoon.

Construction and evaluation of high-quality n-ZnO nanorod/p-diamond heterojunctions.

Vertically-aligned ZnO nanorods (NRs) arrays were synthesized by a low-temperature solution method on boron-doped diamond (BDD) films. The morphology, growth direction, and crystallinity of the ZnO NRs were studied by scanning electron microscopy, X-ray diffraction and cathodoluminescence. Electrical characterization of the ZnO NR/BBD heterostructures revealed characteristic p-n junction properties with an on/off ratio of about 50 at +/- 4 V and a small reverse leakage current approximately 1 microA. Moreover, the junctions showed an ideality factor around 1.0 at a low forward voltage from 0 to 0.3 V and about 2.1 for an increased voltage ranging from 1.2 to 3.0 V, being consistent with that of an ideal diode according to the Sah-Noyce-Shockley theory.

A new duplex real-time PCR for simultaneous detection and differentiation of Tetratrichomonas gallinarum and Trichomonas gallinae.

Tetratrichomonas gallinarum and Trichomonas gallinae are pathogenic avian parasites that infect a wide range of bird species. The pathologic potential of T. gallinarum is controversial, whereas T. gallinae causes disease in many avian species. Infections are often asymptomatic in doves and pigeons; thus, columbids are presumed to represent the natural hosts for trichomonads. The detection of T. gallinarum and T. gallinae is based on direct microscopic observation or a conventional PCR assay. Microscopy is not very sensitive, and identification of the trichomonads at the genus or species level is not possible. Conventional PCR assays have been developed primarily for phylogenetic studies, which detect a wide range of Trichomonas spp. but do not allow their differentiation. We developed a duplex real-time PCR (rtPCR) assay for the simultaneous detection and differentiation of T. gallinarum and T. gallinae. We found that the rtPCR assay detected 102 plasmid DNA copies of T. gallinarum and as few as 101 plasmid DNA copies of T. gallinae.

Social prescription in the US: A pilot evaluation of Mass Cultural Council's "CultureRx".

Introduction: As the field of public health strives to address the impacts of social determinants of health, it has seen increasing interest in community-referral practices that expand health care beyond clinical spaces. However, community arts and culture organizations are rarely included in these practices, despite accumulating evidence of associated health benefits. In addition, such inclusion has not been formally studied. In response, this article offers an evaluation of "CultureRx" in Massachusetts (MA): the first US model of arts on prescription. The program is a partnership between 20 healthcare providers and 12 cultural organizations, in which providers can offer "prescriptions" to cultural experiences to support patients' health. Methods: Evaluation was undertaken to illuminate participant experiences, program successes and barriers, and recommendations for further development. The cultural organizations collected participant data (n = 84) and completed surveys about their own experiences (n = 12). Authors conducted semi-structured focus groups and interviews with healthcare providers (n = 33). Data analysis was customized for each dataset. Results: Findings indicate that participants enjoyed and hoped to repeat their prescribed experiences, which they saw as beneficial to wellbeing. Providers identified the program as a new and critical addition to their toolkits; they also indicated it had a positive effect on their own wellbeing. Cultural organizations reported varied challenges, learnings, and recommendations. Conclusion: The CultureRx pilot suggests that integrating arts/culture assets into health and social care approaches can enrich and improve traditional US models of community referral. By including arts/culture resources when addressing social determinants of health, communities will be better positioned to equitably and holistically advance health.

Adoptive cell therapy using antigen-specific CD4⁻CD8⁻T regulatory cells to prevent autoimmune diabetes and promote islet allograft survival in NOD mice.

AIMS/HYPOTHESIS: A new differentiation pathway for CD4(-)CD8(-) (DN) T cells has recently been identified that exhibits the potent function of peripheral converted DN T cells in suppressing immune responses and provides the potential to treat autoimmune diseases. The aim of this study was to determine if the DN T cells converted from CD4(+) T cells of NOD mice retain the antigen-specific regulatory capacity and prevent autoimmune diabetes in vivo. We also sought to determine if the combination of DN T cells with rapamycin promotes islet allograft survival in autoimmune diabetic NOD recipients. METHODS: NOD CD4(+) T cells were converted to DN T cells in an in vitro mixed-lymphocyte reaction, with or without GAD65 peptide, as previously reported. The antigen-specific DN T cells were adoptively transferred to NOD/SCID mice, new-onset diabetic NOD mice or islet-allograft-recipient NOD mice as the part of cell-based therapy. The development of diabetes and allograft survival was assessed by monitoring blood glucose levels. RESULTS: NOD CD4(+) T cells were converted in vitro to DN T cells at a rate of 50% and expressed unique cell features. The DN T cells from NOD donors blocked autoimmunity and prevented diabetes in NOD models, and these effects were even greater for GAD65-peptide-primed DN T cells. DN T cells acted in conjunction with rapamycin to suppress alloantigen-triggered T cell proliferation, promoted apoptosis and prolonged islet allograft survival in NOD recipients. CONCLUSIONS/INTERPRETATION: Administration of the islet beta cell antigen-specific DN T cells can prevent the development of autoimmune diabetes and promote islet allograft survival in NOD mice.

Ocular Perfusion Pressure and Severity of Glaucoma: Is There a Link?

AIM AND OBJECTIVE: To establish the association between 12-month inter-visits ocular perfusion pressure (OPP) and severity of glaucoma. MATERIALS AND METHODS: A total of 164 eyes (60 primary open-angle glaucoma, 52 normal-tension glaucoma, and 52 primary angle-closure glaucoma) of 164 patients were analyzed in this prospective cohort study. Patients who demonstrated good compliance to treatment were recruited. The severity of glaucoma was stratified according to the Advanced Glaucoma Intervention Study (AGIS) score based on reliable and reproducible visual field analysis at baseline. OPP was obtained at baseline and a 3-monthly follow-up visit over a 12-month duration. The pattern and fluctuation of mean OPP were studied. Repetitive measure ANOVA and one-way ANOVA were used for statistical analysis. RESULTS: The inter-visits mean OPP (p = 0.010), systolic OPP (p = 0.020), diastolic OPP (p = 0.010), systolic blood pressure (p = 0.040), and diastolic blood pressure (p = 0.006) showed significant difference with severity of glaucoma. There was no significant difference between mean inter-visits intraocular pressure (IOP) and severity of glaucoma (p = 0.410). The end-stage glaucoma group had the lowest mean OPP and widest inter-visit mean OPP fluctuation. Early and mild glaucoma patients demonstrated higher mean OPP compared with moderate, severe, and end-stage glaucoma. CONCLUSION: There is a significant association between OPP and the severity of glaucoma. Balancing blood pressure and IOP is important in optimizing adequate perfusion and prevent further damage to the optic nerve head. HOW TO CITE THIS ARTICLE: Ch'ng TW, Chua CY, Ummi Kalsom MA, et al. Ocular Perfusion Pressure and Severity of Glaucoma: Is There a Link? J Curr Glaucoma Pract 2021;15(2):78-85.

Prospects of Wannier functions in investigating photonic crystal all-optical devices for signal processing.

Wannier functions derived from Bloch functions have been identified as an efficient means of analyzing the properties of photonic crystals in which localized functions have now opened the door for 2D and 3D structures containing defects to be investigated. In this paper, based on the Maxwell equations in diagonalized form and utilizing Bloch waves we have obtained an equivalent system of algebraic equations in eigenform. By establishing and exploiting several distinct properties of the resulting eigenpairs, we demonstrate an ability to construct Wannier functions associated with the simplest one-dimensional photonic structure. More importantly, the numerical investigation of the inner- and intra-band orthonormality conditions as well as Hilbert space partitioning features shows a capability for multi-resolution analysis that will make all-optical signal processing devices with photonic crystal structures feasible.

Effect of weight loss on markers of triglyceride-rich lipoprotein metabolism in the metabolic syndrome.

BACKGROUND: Hypertriglyceridaemia, a consistent feature of dyslipidaemia in the metabolic syndrome (MetS), is related to the extent of abdominal fat mass and altered adipocytokine secretion. We determined the effect of weight loss by dietary restriction on markers of triglyceride-rich lipoprotein (TRL) metabolism and plasma adipocytokines. DESIGN: Thirty-five men with MetS participated in a 16 week randomized controlled dietary intervention study. Apolipoprotein (apo) C-III, apoB-48, remnant-like particle (RLP)-cholesterol, total adiponectin, high-molecular weight (HMW) adiponectin, and retinol-binding protein-4 (RBP-4) concentrations were measured using immunoassays. RESULTS: Compared with weight maintenance (n = 15), weight loss (n = 20) significantly decreased body weight, plasma insulin, triglycerides, total cholesterol, low-density lipoprotein (LDL)-cholesterol and lathosterol (P < 0.05). Weight loss also decreased plasma concentrations of apoC-III (-33%), apoB-48 (-37%), very low-density lipoprotein (VLDL)-apoB (-43%), RLP-cholesterol (-48%), and RBP-4 (-20%), and significantly increased plasma total (+20%) and HMW-adiponectin (+19%) concentrations. In the weight loss group, reduction in plasma apoC-III was associated (P < 0.05) with reduction in plasma apoB-48, VLDL-apoB, RLP-cholesterol and triglycerides. Increase in total adiponectin was associated (P < 0.05) with the reduction in plasma VLDL-apoB and triglycerides. The changes in HMW-adiponectin and RBP-4 were not associated with changes in plasma apoB-48, apoC-III, VLDL-apoB, RLP-cholesterol or triglycerides. In multiple regression analysis including changes in visceral fat, insulin and total adiponectin concentrations, the fall in plasma apoC-III concentration was an independent predictor of the reductions in plasma apoB-48, VLDL-apoB, RLP-cholesterol and triglycerides concentrations. CONCLUSIONS: In men with MetS, weight loss decreases the plasma concentrations of apoB-48, VLDL-apoB, RLP-cholesterol and triglycerides. This effect could partly relate to concomitant changes in plasma apoC-III and adiponectin concentrations that accelerate the catabolism of TRLs.

Studies on the interaction of propranolol with erythrocyte membranes.

The interaction of propranolol with erythrocyte membranes at concentrations stabilizing intact erythrocytes against hypotonic hemolysis produced corresponding perturbations in membrane protein and particularly membrane phospholipid components as monitored by increases in the reactivity of membrane amino and sulfhydryl groups towards trinitrobenzenesulfonic acid and 5,5'-dithio-bis(2-nitro-benzoic acid), respectively. Membrane-propranolol interactions were also analyzed in terms of alterations produced in the kinetic properties of membrane enzymes. These experiments provided evidence that propranolol-induced perturbations were sufficiently generalized as to influence the activity of enzymatic processes associated with both inner and outer membrane surfaces. Configurational changes in membrane phospholipids were implicated in these effects of propranolol, which included alterations in functionally significant membrane-cation interactions, It is suggested that the findings described here may provide a basis for understanding molecular aspects of membrane stabilization in other systems.

Inexpensive color evaluation of dye-based pressure-sensitive films for plantar studies.

Dye-based pressure-sensitive films are advantageous in plantar pressure studies due to their ease of use, cost-effectiveness, and ability to produce measurements within the shoe. To circumvent the use of proprietary equipment and software to relate the dye-stained film to load, an alternative approach of using a conventional flatbed scanner and generic image processing software is attempted here instead. The technique revealed high linear increasing and decreasing trends for the respective red and blue normalized intensities (R(2) > 0.95) and low standard deviation in all readings (<0.06) overall. By subtracting the blue from the red normalized intensity, it was discovered that the measurement sensitivity could be doubled. The results here confirm the viability of using a conventional flatbed scanner and generic image processing software to relate the dye-stained pressure films to load. The adoption of this approach promises substantial cost savings.

Reducing the spread of HIV infection in sub-Saharan Africa: some demographic and economic implications.

Any reduction in the rate of spread of HIV infection has consequences for the incidence and demographic effects of AIDS. In this paper, output from a published mathematical model of the dynamics of HIV transmission through heterosexual contact is used to study the implications of reducing HIV transmission on demographic patterns and national health budgets in sub-Saharan Africa. The major conclusion is that both the timing and the effectiveness of reducing HIV transmission are non-linearly related to their potential demographic and economic effects. The analysis emphasizes the benefits to be gained from a concerted effort to reduce the spread of HIV infection as early as possible in the time course of the epidemic.

PIP: A previously published mathematical model of the transmission of dynamics of HIV is used to simulate the demographic and economic consequences of introducing various degrees of control measures to reduce heterosexual transmission of HIV in sub-Sahara Africa. The model is fully age-structured and its output is projection over time (100 years) of total population size, broken down by age and sex, and numbers with HIV or AIDS. The doubling time of the epidemic is set at 1.5 years; the mean incubation period for AIDS 8 years for adults and 2 years for children; life expectancy of infected persons is set at 1 year; probability of heterosexual transmission 10% per partner contact; that of vertical transmission 50%. The factor beta c, or average rate at which an infected person infects others, varies with level of control introduced. For a population of 16.6 million multiplying at 3.8% per year, with AIDS and no controls, growth rates will begin to decline at year 30, to reach 8.6 million by year 100. Without AIDS, it would have reached 740 million. With AIDS, the structure of the population would change to a higher proportion under 15 and over 25, but lower proportion between 15-25 years. Economically, assuming a GNP of $300 per capita, and an expenditure of $100 per AIDS patient, by year 50 2.4% of the GNP would be spent treating AIDS victims. Figures are also estimated for a fixed or falling GNP, such that funds to spend on AIDS treatment per person would fall over time. If control measures were taken, savings in treatment costs would be substantial, as much as $2.4 billion if transmission were reduced 75% over 25 years. If was noted that sub- Sahara African countries simply do not have funds to pay for Western style treatment of AIDS patients. The cost of the drug zidovudine (AZT) for 1 person is more than that of 1 community health center for a year. Already half the hospital beds are taken up by AIDS patient in some urban areas.

The influence of different sexual-contact patterns between age classes on the predicted demographic impact of AIDS in developing countries.

A model is developed to describe the spread of HIV within heterosexual communities and the demographic impact of AIDS. The model combines epidemiologic and demographic processes and is designed to mirror the impact of AIDS in sub-Saharan Africa. Refinements on past work in this area include unequal probabilities for transmission from females to males and from males to females, the inclusion of an age- and sex-dependent sexual-partner choice function and distributed incubation plus infectious periods. Numerical studies suggest that unequal transmission probabilities (weighted to a greater probability from males to females than vice versa), and the tendency of males to choose sexual partners of the opposite sex younger than themselves, both act to increase the demographic impact of AIDS over that predicted with equal transmission between the sexes and partner choice restricted within given age classes. Analyses support the conclusions of past work that the epidemic will only have a small detrimental impact on the dependency ratio of a population (the ratio of dependents to working adults) even when a weighting is added to take account of the extra burden imposed by the care of adult AIDS patients. However, a small increase in the ratio can imply a significant rise in the number of dependents within the population. Stimulation studies of the impact of changes in behavior to reduce transmission highlight to the need to induce such changes as early as possible in the course of the epidemic in order to minimize its impact. Directions for future research are discussed emphasizing the need to acquire quantitative data on sexual habits and to construct models to represent heterogeneity in sexual behavior.

PIP: A mathematical model of the likely demographic impact of acquired immunodeficiency syndrome (AIDS) suggest that, in the countries of sub- Saharan Africa, this impact can be expected to increase in the years ahead as a result of unequal transmission probabilities (weighted toward a greater probability from males to females) and the tendency of men to select female sexual partners from a younger class. The model refines earlier work in its consideration of predicted influence of human immunodeficiency virus (HIV) infection on the age structure and dependency ratio of the population, the significance of patterns of sexual contact between the age classes of the 2 sexes, and the impact of control measures such as health education and condom use. The assumptions of a doubling time of 1.5 years in the early stages of the epidemic and a 3 times greater probability of transmission from infected males to susceptible females rather than vice versa produce the observation that net population growth rate will change from positive to negative 25 years after introduction of the AIDS virus. The dependency ration is not significantly affected by AIDS due to the counterbalancing effects of deaths from vertical and horizontal transmission. On the other hand, if dependency ratio is defined to encompass the burden created by the care of AIDS patients, the disease-related ratio will increase over time. The most significant social factor in terms of the impact of AIDS on net fertility is the tendency of African men to choose female sexual partners at least 5 years younger than themselves. Finally, the numerical analyses indicate that the introduction of AIDS control measures 10 years after the onset of the epidemic will slow the progression of the epidemic and prevent a change in the population growth rate from positive to negative over a 100-year period.

The optical mouse as an inexpensive region-of-interest position recorder in optical microscopy.

In optical microscopy, the microscopic features of interest typically have to be derived from regions that are spatially distributed over the sample. While the features to be analyzed may be minute, the regions from where they must be obtained from may be located quite far apart from one another. If the features are not distinct enough to allow easy visual discrimination, it would be tedious and time-consuming to attempt to recall and revisit these regions of interest. One method to overcome this difficulty would be to note and record the graduated markings on the microscope, or to use built-in position encoders. The former is tedious while the latter is generally expensive. Here, a region-of-interest position-recording implement based on the use of an optical mouse is presented. It is inexpensive and easily adaptable to the manual stage of any optical microscope.

Observation of dynamic samples using simple coverslip fluidics.

The ability to observe samples undergoing controlled fluid flow under the microscope is important for studying biochemical processes and motion dynamics. We describe here a simple method to achieve this using coverslips shaped using a fiber scribe. Testing showed good directional flow control within the test range of 0-1 ml/min flow rate and an ability to sustain a flow rate up to approximately 1 ml/min. Testing with a sealed T-channel coverslip demonstrated the ability to construct fluid network branches with this scheme. We also demonstrated the usefulness of this procedure in motion dynamic studies of Dunaliella algae swimming under fluid flow.