AIDS patients have increased surfactant protein D but normal mannose binding lectin levels in lung fluid.

BACKGROUND: Surfactant protein D (SP-D) and Mannose Binding Lectin (MBL) are collectins that have opsonic and immunoregulatory functions, are found in lung fluid and interact with the human immunodeficiency virus (HIV). We compared collectin levels in lung fluid and serum from HIV infected and normal subjects to determine if alterations in lung collectin levels were associated with HIV infection and might result in increased susceptibility to other pulmonary infections. METHODS: Blood and bronchoalveolar lavage samples were collected from 19 HIV-infected individuals and 17 HIV-uninfected individuals, all with normal chest X ray at time of study. HIV viral loads and peripheral blood CD4+ T cell counts were measured in all subjects. SP-D was measured in lung fluid, and MBL in both lung fluid and serum. RESULTS: SP-D levels were not significantly different in lung fluid from HIV-uninfected (median 406.72 ng/ml) and HIV-infected individuals with high CD4 count (CD4 >200) (median 382.60 ng/ml) but were elevated in HIV-infected individuals with low CD4 count (median 577.79 ng/ml; Kruskall Wallis p < 0.05). MBL levels in serum were not significantly different between HIV-uninfected and HIV-infected individuals (median 1782.70 ng/ml vs 2639.73 ng/ml) and were not detectable in lung fluid. CONCLUSION: SP-D levels are increased in lung fluid from AIDS patients but not in patients with early HIV infection. MBL levels are not altered by HIV infection or AIDS. There is no evidence that altered pulmonary collectin levels result in susceptibility to infection in these patients

Theoretical studies of some inelastic collision processes

i. The quadrupole-quadrupole mechanism alone cannot account for all the observed rate constants though it does account almost entirely for near-resonant processes. (Te/H₂, I/HD). In particular, isotopic ratios, which are largely independent of the details of the electronic eigen functions, are not correctly predicted. Nevertheless, the long-range mechanism is clearly an important one and cannot be dismissed.ii. Neglecting rotational and populational factors, processes which differ in ΔE from the nearest resonant process by more than 200 cm⁻¹ at 300K may be neglected.iii. The calculated rate constants are not sensitive to the choice of co-ordinate system.iv. For the rotating co-ordinate system calculations, the symmetrised, straight line trajectory is a.useful approximation.v. The observed rate constants may increase or decrease with increasing temperature.vi. Provided a(v) does not vary too rapidly around V=Vm the approximation K=VO(Vm) is a useful one

An Exploratory Multiple Case Study of Discipline Practices in a Major Metropolitan Public School District: A Look into the School to Prison Pipeline

The school to prison pipeline is a phenomenon fed by exclusionary discipline practices that increase the likelihood that a student will have an interaction with the juvenile or criminal justice system at some time in their life; this phenomenon disproportionately affects Black students. Understanding the problem is key to slowing down the school to prison pipeline. This study of a school district in Missouri explores questions about how interpersonal relationships, implicit bias awareness, and school policies influence the learning environment, and how those factors relate to school discipline, which ultimately can lead to the school to prison pipeline. Drawing data from exploratory multiple case study interviews, numerous themes emerged. Relationships are important when making changes in schools. Staff were forced to develop plans to support students by building relationships, managing teaching expectations, and developing alternatives to suspension. The new policy positively affected law enforcement officers’ interactions with students. The study has important implications for school practitioners; namely policy change is an effective method to lessen school suspensions thus decreasing the school to prison pipeline. The implications for law enforcement officers working in schools is that they can also work to reduce the school to prison pipeline through improved relationships with students and families. They are an invaluable resource to students, families, and school staff to support students and to prevent them from entering the criminal justice system later in life

Factors which influence organisational knowledge sharing

This research investigated which combination of factors had a positive and significant impact on knowledge sharing within an organisation. By finding this combination it will allow organisations to prioritise resources to specific factors that are seen to positively affect knowledge sharing. One hundred and seventy nine employees of a prominent South African company gave an indication into which factors in combination would provide a model that best predicts a positive impact on knowledge sharing. Statistical testing carried out on the resulting data gave an indication of the best fitting model. It was found that three of the four identified factors contributed 62% to the overall positive effect on knowledge sharing when measured together. CopyrightDissertation (MBA)--University of Pretoria, 2010.Gordon Institute of Business Science (GIBS)unrestricte

Tunable fibre-coupled multiphoton microscopy with a negative curvature fibre

Negative curvature fibre (NCF) guides light in its core by inhibiting the coupling of core and cladding modes. In this work, an NCF was designed and fabricated to transmit ultrashort optical pulses for multiphoton microscopy with low group velocity dispersion (GVD) at 800 nm. Its attenuation was measured to be <0.3 dB m(-1) over the range 600-850 nm and the GVD was -180 ± 70 fs(2)  m(-1) at 800 nm. Using an average fibre output power of ∼20 mW and pulse repetition rate of 80 MHz, the NCF enabled pulses with a duration of <200 fs to be transmitted through a length of 1.5 m of fibre over a tuning range of 180 nm without the need for dispersion compensation. In a 4 m fibre, temporal and spectral pulse widths were maintained to within 10% of low power values up to the maximum fibre output power achievable with the laser system used of 278 mW at 700 nm, 808 mW at 800 nm and 420 mW at 860 nm. When coupled to a multiphoton microscope, it enabled imaging of ex vivo tissue using excitation wavelengths from 740 nm to 860 nm without any need for adjustments to the set-up

Designing smart toys for the cognitive enrichment of elephants

This project investigates the potential for designing playful cognitive enrichment activities for captive elephants. We explore the usefulness of applying conceptual frameworks from HCI and game design to the problem of developing species-specific smart toys that promote natural behaviour and provide stimulation

Fertility intentions and use of contraception among monogamous couples in northern Malawi in the context of HIV testing: a cross-sectional analysis.

CONTEXT: Knowledge of HIV status may influence fertility desires of married men and women. There is little knowledge about the importance of this influence among monogamously married couples and how knowledge of HIV status influences use of contraception among these couples. METHODOLOGY: We carried out a cross-sectional analysis of interview data collected between October 2008 and September 2009 on men aged 15-59 years and women aged 15-49 years who formed 1766 monogamously married couples within the Karonga Prevention Study demographic surveillance study in northern Malawi. RESULTS: 5% of men and 4% of women knew that they were HIV positive at the time of interview and 81% of men and 89% of women knew that they were HIV negative. 73% of men and 83% of women who knew that they were HIV positive stated that they did not want more children, compared to 35% of men and 38% of women who knew they were HIV negative. Concordant HIV positive couples were more likely than concordant negative couples to desire to stop child bearing (odds ratio 11.5, 95%CI 4.3-30.7, after adjusting for other factors) but only slightly more likely to use contraceptives (adjusted odds ratio 1.5 (95%CI 0.8-3.3). CONCLUSION: Knowledge of HIV positive status is associated with an increase in the reported desire to cease childbearing but there was limited evidence that this desire led to higher use of contraception. More efforts directed towards assisting HIV positive couples to access and use reproductive health services and limit HIV transmission among couples are recommended

easySTORM: a robust, lower-cost approach to localisation and TIRF microscopy

TIRF and STORM microscopy are super-resolving fluorescence imaging modalities for which current implementations on standard microscopes can present significant complexity and cost. We present a straightforward and low-cost approach to implement STORM and TIRF taking advantage of multimode optical fibres and multimode diode lasers to provide the required excitation light. Combined with open source software and relatively simple protocols to prepare samples for STORM, including the use of Vectashield for non-TIRF imaging, this approach enables TIRF and STORM imaging of cells labelled with appropriate dyes or expressing suitable fluorescent proteins to become widely accessible at low cost

Electromyographic biofeedback for tension control during fine and gross motor skill acquisition

The presence of residual muscular tension has been implicated as a detrimental influence on the performance and learning of motor skills. A method for reducing muscular tension has been provided by the recent advent of biofeedback training. Thirty young adult males were subjected to tests of stabilometer balancing skill and pursuitrotor tracking skill, which represented gross and fine motor activity respectively. Following pre-tests, the subjects were ranked by performance scores and divided into identical triplicates. Two experimental groups and a control group were formed when one subject of each triplicate was assigned to each group. The two experimental groups were trained by electromyographic biofeedback techniques to reduce muscular tension in the frontalis muscles. After a total of three hours of training for the experimental subjects, all subjects were re-evaluated on the same motor skill tasks. One experimental group received electromyographic feedback during the post-tests. Analysis of variance groups by trials, analysis of variance of difference means, and t tests of scores representing performance and tension suggested that: a) electromyographic biofeedback training significantly (1) reduces tension induced by novel motor skill learning and (2) improves motor performance of fine and gross motor skills; b) transfer of tension-control training of a general nature facilitates learning and performance more than direct biofeedback during performance; and c) a higher tension level is necessary for performance of fine motor tasks as tension correlates positively with performance. Residual tension reduction and control were particularly facilitated by electromyograph biofeedback methods, which may have profound implications for the management of stress in a variety of situations