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The effect of magnetic field on the diffusion behavior of aluminum in Ni–Al alloy was investigated using diffusion couple technique. The results indicated that the diffusion of aluminum in the direction parallel to the magnetic field was suppressed and the frequency factor pertaining to the diffusion coefficient was decreased without much variation of the activation energy. The inhibition of diffusion with magnetic field was discussed based on the ambipolar diffusion theory.

The diffusivity in the Ni-Al system with and without an alternating magnetic field (AMF) was investigated by the diffusion couple technique. It was found that the diffusion coefficient was increased with increasing AMF intensity. The enhanced diffusivity in the AMF can be ascribed to the increase in the dislocation density in the diffusion couples, which was demonstrated by the broadening of X-ray diffraction peaks. The higher dislocation density was induced by the magnetoplastic effect (MPE). The theoretical calculation based on the MPE is in agreement with the experimental values.

Kaposi sarcoma-associated herpesvirus (KSHV) is transmitted by routes such as homosexual intercourse and is associated with HIV infection in industrialized countries. However, there is little information about its transmission in developing countries where Kaposi sarcoma is an endemic disease.To examine KSHV seroprevalence in young adults in a general, rural Ugandan population, and to compare this prevalence with rates of known sexually transmitted infections.The seroprevalence of KSHV was compared with the epidemiology of sexually transmitted diseases in 523 sexually active subjects aged 15 to 29 years who were randomly selected from a general population cohort in rural Rakai District, Uganda. Participants provided in-home interview data and specimens. Sera were tested for KSHV using immunofluorescence assay and immunoblot for lytically expressed recombinant KSHV ORF65.2. Sera were also tested for HIV type 1, herpes simplex virus type 2, and syphilis.The prevalence of KSHV was significantly higher in participants 15 to 19 years compared with older persons 25 to 29 years (45.0% and 36.1%, respectively; adjusted odds ratio, 0.48; 95% CI, 0.28-0.82). In contrast, herpes simplex virus type 2 and HIV type 1 prevalence increased with age. Kaposi sarcoma-associated herpesvirus serostatus was not associated with HIV type 1, syphilis, herpes simplex virus type 2, or number of sexual partners. Homosexual and anal intercourse were reported by less than 1% of participants.Kaposi sarcoma-associated herpesvirus does not appear to be a heterosexually transmitted infection in rural Uganda.

To assess mortality impact of HIV in rural Uganda.An open cohort of 19983 adults aged 15-59 years, in Rakai district was followed at 10 month intervals for four surveys. Sociodemographic characteristics and symptomatology/disease conditions were assessed by interview. Deaths among residents and out-migrants were identified household census. Mortality rates were computed per 1000 person years (py) and the rate ratio (RR) of death in HIV-positive/HIV-negative subjects, and the population attributable fraction (PAF) of death were estimated according to sociodemographic characteristics. Mortality associated with potential AIDS defining symptoms and signs was assessed.HIV prevalence was 16.1%. Mortality was 132.6 per 1000 py in HIV-infected versus 6.7 per 1000 py in uninfected subjects, and 73.5% of adult deaths were attributable to HIV infection. Mortality increased with age, but the highest attributable risk of HIV associated deaths were observed in persons aged 20-39 years (PAF80%) and in women. HIV associated mortality was highest in the better educated (PAFor = 75%) and among government employees (PAFor = 82%). Of the HIV-positive subjects 40.5% reported no illness10 months preceding death, symptoms were poor predictors of death (sensitivity 1.6-38.8%), and only 9.1% met the World Health Organization clinical definition of AIDS. Infant mortality rates in babies of HIV-infected and uninfected mothers were 209.4 and 97.7 per 1000, respectively.HIV is taking substantial toll in this population, particularly among the younger better educated adults, and infants. Symptomatology or the World Health Organization definition of AIDS are poor predictors of death.

Male circumcision is associated with reduced HIV acquisition. HIV acquisition was determined in a cohort of 5507 HIV-negative Ugandan men and in 187 HIV-negative men in discordant relationships. Transmission was determined in 223 HIV-positive men with HIV-negative partners. HIV incidence per 100 person years (py) and adjusted rate ratios (RR) and 95% confidence intervals (CI) were estimated by Poisson regression. HIV-1 serum viral load was determined for the seropositive partners in HIV- discordant couples. The prevalence of circumcision was 16.5% for all men; 99.1% in Muslims and 3.7% in non-Muslims. Circumcision was significantly associated with reduced HIV acquisition in the cohort as a whole (RR 0.53 CI 0.33-0.87) but not among non- Muslim men. Prepubertal circumcision significantly reduced HIV acquisition (RR 0.49 CI 0.26-0.82) but postpubertal circumcision did not. In discordant couples with HIV-negative men no seroconversions occurred in 50 circumcised men whereas HIV acquisition was 16.7/100 py in uncircumcised men (P = 0.004). In couples with HIV-positive men HIV transmission was significantly reduced in circumcised men with HIV viral loads of

Background and Methods We examined the influence of viral load in relation to other risk factors for the heterosexual transmission of human immunodeficiency virus type 1 (HIV-1). In a community-based study of 15,127 persons in a rural district of Uganda, we identified 415 couples in which one partner was HIV-1–positive and one was initially HIV-1–negative and followed them prospectively for up to 30 months. The incidence of HIV-1 infection per 100 person-years among the initially seronegative partners was examined in relation to behavioral and biologic variables. Results The male partner was HIV-1–positive in 228 couples, and the female partner was HIV-1–positive in 187 couples. Ninety of the 415 initially HIV-1–negative partners seroconverted (incidence, 11.8 per 100 person-years). The rate of male-to-female transmission was not significantly different from the rate of female-to-male transmission (12.0 per 100 person-years vs. 11.6 per 100 person-years). The incidence of seroconversion was highest among ...

The differential thermal analysis (DTA) apparatus has been designed in order to investigate the effect of magnetic fields on solid-melt phase transformation in pure bismuth. The endothermic peaks of DTA curves show that melting is insensitive to magnetic fields, which can be verified from thermodynamics. However, the exothermic peak obviously shifts to higher temperature as the magnetic field strength increases, from which the magnetic field does not affect the crystal growth but nucleation. On the basis of the assumption that there is an intermediate state between a crystal nucleus and a liquid atom, one possible reason for the shift of exothermic peaks is that kinetic barrier of nucleation is lowered and nucleation is activated by magnetic fields.

Summary Background The study tested the hypothesis that community-level control of sexually transmitted disease (STD) would result in lower incidence of HIV-1 infection in comparison with control communities. Methods This randomised, controlled, single-masked, community-based trial of intensive STD control, via home-based mass antibiotic treatment, took place in Rakai District, Uganda. Ten community clusters were randomly assigned to intervention or control groups. All consenting residents aged 15–59 years were enrolled; visited in the home every 10 months; interviewed; asked to provide biological samples for assessment of HIV-1 infection and STDs; and were provided with mass treatment (azithromycin, ciprofloxacin, metronidazole in the intervention group, vitamins/anthelmintic drug in the control). Intention-to-treat analyses used multivariate, paired, cluster-adjusted rate ratios. Findings The baseline prevalence of HIV-1 infection was 15·9%. 6602 HIV-1-negative individuals were enrolled in the intervention group and 6124 in the control group. 75·0% of intervention-group and 72·6% of control-group participants provided at least one follow-up sample for HIV-1 testing. At enrolment, the two treatment groups were similar in STD prevalence rates. At 20-month follow-up, the prevalences of syphilis (352/6238 [5·6%) vs 359/5284 [6·8%]; rate ratio 0·80 [95% Cl 0·71–0·89]) and trichomoniasis (182/1968 [9·3%] vs 261/1815 [14·4%]; rate ratio 0·59 [0·38–0·91]) were significantly lower in the intervention group than in the control group. The incidence of HIV-1 infection was 1·5 per 100 person-years in both groups (rate ratio 0·97 [0·81-1·16]). In pregnant women, the follow-up prevalences of trichomoniasis, bacterial vaginosis, gonorrhoea, and chlamydia infection were significantly lower in the intervention group than in the control group. No effect of the intervention on incidence of HIV-1 infection was observed in pregnant women or in stratified analyses. Interpretation We observed no effect of the STD intervention on the incidence of HIV-1 infection. In the Rakai population, a substantial proportion of HIV-1 acquisition appears to occur independently of treatable STD cofactors.

To assess whether circumcision performed on postpubertal men affords the same level of protection from HIV-1 acquisition as circumcisions earlier in childhood.Cross-sectional study of a population-based cohort.Rakai district, rural Uganda.A total of 6821 men aged 15-59 years were surveyed and venous blood samples were tested for HIV-1 and syphilis. Age at circumcision was dichotomized into men who were circumcised before or at age 12 years (prepubertal) and men circumcised after age 12 years (postpubertal). Postpubertal circumcised men were also subdivided into those reporting circumcision at ages 13-20 years andor = 21 years.HIV-1 prevalence was 14.1% in uncircumcised men, compared with 16.2% for men circumcised at ageor = 21 years, 10.0% for men circumcised at age 13-20 years, and 6.9% in men circumcised at ageor = 12 years. On bivariate analysis, lower prevalence of HIV-1 associated with prepubertal circumcision was observed in all age, education, ethnic and religious groups. Multivariate adjusted odds ratio of prevalent HIV-1 infection associated with prepubertal circumcision was 0.39 [95% confidence interval (CI), 0.29-0.53]. In the postpubertal group, the adjusted odds ratio for men circumcised at ages 13-20 years was 0.46 (95% CI, 0.28-0.77), and 0.78 (95% CI, 0.43-1.43) for men circumcised after age 20 years.Prepubertal circumcision is associated with reduced HIV risk, whereas circumcision after age 20 years is not significantly protective against HIV-1 infection. Age at circumcision and reasons for circumcision need to be considered in future studies of circumcision and HIV risk.

To assess the effects of HIV-1 and other sexually transmitted infections on pregnancy, we undertook cross-sectional and prospective studies of a rural population in Rakai district, Uganda.4813 sexually active women aged 15-49 years were surveyed to find out the prevalence of pregnancy by interview and selective urinary human chorionic gonadotropin tests. The incidence of recognised conception and frequency of pregnancy loss were assessed by follow-up. Samples were taken to test for HIV-1 infection, syphilis, and other sexually transmitted diseases.At time of survey 757 (21.4%) of 3544 women without HIV-1 infection or syphilis were pregnant, compared with 46 (14.6%) of 316 HIV-1-negative women with active syphilis, 117 (14.2%) of 823 HIV-1-positive women with no concurrent syphilis, and 11 (8.5%) of 130 women with both syphilis and HIV-1 infection. The multivariate adjusted odds ratio of pregnancy in HIV-1-infected women was 0.45 (95% CI 0.35-0.57); the odds of pregnancy were low both in HIV-1-infected women without symptoms (0.49 [0.39-0.62]) and in women with symptoms of HIV-1-associated disease (0.23 [0.11-0.48]). In women with concurrent HIV-1 infection and syphilis the odds ratio was 0.28 (0.14-0.55). The incidence rate of recognised pregnancy during the prospective follow-up study was lower in HIV-1-positive than in HIV-1-negative women (23.5 vs 30.1 per 100 woman-years; adjusted risk ratio 0.73 [0.57-0.93]). Rates of pregnancy loss were higher among HIV-1-infected than uninfected women (18.5 vs 12.2%; odds ratio 1.50 [1.01-2.27]). The prevalence of HIV-1 infection was significantly lower in pregnant than in non-pregnant women (13.9 vs 21.3%).Pregnancy prevalence is greatly reduced in HIV-1-infected women, owing to lower rates of conception and increased rates of pregnancy loss. HIV-1 surveillance confined to pregnant women underestimates the magnitude of the HIV-1 epidemic in the general population.A cross-sectional, prospective study conducted in Uganda's rural Rakai District indicated pregnancy prevalence is substantially reduced in women infected with HIV. A total of 4813 women 15-49 years of age who had at least one sexual partner in the previous year and were unaware of their HIV status were enrolled. 953 women (19.8%) were HIV-positive and 446 (9.3%) were diagnosed with active syphilis. 931 women (19.3%) became pregnant during the study period (1989-92). The pregnancy rate was 21.4% among women with no serologic evidence of HIV or syphilis compared with 14.6% among HIV-negative women with active syphilis and 8.5% among women infected with both HIV and syphilis. The pregnancy rate also was significantly higher among the 833 asymptomatic HIV-infected women (14.3%) than the 120 with clinical symptoms (7.5%). Symptomatic HIV-1 infection in male partners did not account for the lower pregnancy rate in HIV-positive women. After controls for age, marital status, gravidity, contraceptive use, lactation, subfertility, and time since last intercourse, the adjusted odds ratio of pregnancy among all HIV-positive women compared to women without HIV or syphilis was 0.45 (95% confidence interval, 0.35-0.57). Among the 3340 women who were not pregnant at baseline and were locatable, the pregnancy rate during follow-up was 23.5 per 100 woman-years among HIV-positive women and 30.1 per 100 woman-years among those without HIV or syphilis. Rates of pregnancy loss were higher among HIV-infected women (18.5%) than HIV-negative women (12.2%). The prevalence of HIV-1 infection was significantly lower in pregnant than nonpregnant women (13.9% and 21.3%, respectively). These findings indicate that, if HIV surveillance is confined to pregnant women, the prevalence of HIV-1 among women of reproductive age will be seriously underestimated.

Summary Background In-vitro research has suggested that bacterial vaginosis may increase the survival of HIV-1 in the genital tract. Therefore, we investigated the association of HIV-1 infection with vaginal flora abnormalities, including bacterial vaginosis and depletion of lactobacilli, after adjustment for sexual activity and the presence of other sexually transmitted diseases (STDs). Methods During the initial survey round of our community-based trial of STD control for HIV-1 prevention in rural Rakai District, southwestern Uganda, we selected 4718 women aged 15–59 years. They provided interview information, blood for HIV-1 and syphilis serology, urine for detection of Chlamydia trachomatis and Neisseria gonorrhoeae , and two self-administered vaginal swabs for culture of Trichomonas vaginalis and gram-stain detection of vaginal flora, classified by standardised, quantitative, morphological scoring. Scores 0–3 were normal vaginal flora (predominant lactobacilli). Higher scores suggested replacement of lactobacilli by gram-negative, anaerobic microorganisms (4–6 intermediate; 7–8 and 9–10 moderate and severe bacterial vaginosis). Findings HIV-1 frequency was 14·2% among women with normal vaginal flora and 26·7% among those with severe bacterial vaginosis (p Interpretation This cross-sectional study cannot show whether disturbed vaginal flora increases susceptibility to HIV-1 infection. Nevertheless, the increased frequency of HIV-1 associated with abnormal flora among younger women, for whom HIV-1 acquisition is likely to be recent, but not among older women, in whom HIV-1 is likely to have been acquired earlier, suggests that loss of lactobacilli or presence of bacterial vaginosis may increase susceptibility to HIV-1 acquisition. If this inference is correct, control of bacterial vaginosis could reduce HIV-1 transmission.

Objective: Various birth defects and untoward perinatal outcomes have been claimed to be associated with pregnancies conceived by gametes aged in vivo before fertilization. Thus, these outcomes were systematically assessed in pregnancies occurring in natural family planning (NFP) users. Our international multicenter cohort study of NFP pregnancies (n = 877) is by far the largest systematic study designed to assess pregnancy outcome and is of sufficient power to allow us to address the concern of low birth weight (< 2500 g) and preterm delivery (< 37 weeks gestation).

A multicenter cohort study was designed to assess pregnancy outcome among natural family planning (NFP) users, and provide the opportunity to address complications in NFP users by planning status and by timing of conception with respect to day of ovulation. There were 877 singleton births in this sample. Complications evaluated were abnormal vaginal bleeding, urinary tract infection, vaginal infection, hypertension of pregnancy, proteinuria, glycosuria, and anemia.

Conceptions involving aging gametes are of relevance to natural family planning (NFP) because women using NFP to avoid pregnancy abstain from intercourse during the fertile time of the cycle. To help verify the safety of pregnancies occurring among NFP practitioners, our group has, since 1986, conducted a large cohort study involving six experienced NFP centers. Timing of conception was determined from NFP charts, in which women recorded days on which intercourse occurred. The number of days from the most probable conception intercourse to probable day of ovulation was first determined, and used as an estimate of the time gametes remained in the genital tract before fertilization. Several studies have already been completed, cohort as well as case-control in nature.

A method of attitude-aided magnetometers/SINS/ GNSS integration was proposed for low-cost guided ammunitions at fast spinning rate. Magnetometers-aided attitude updating of SINS was utilized to inhibit the drift of SINS attitude, and GNSS-aided SINS was used to reduce the error of position and velocity. An approach of roll angle determination was developed by geomagnetic intensity in body frame. SINS error model based on a first-order Gauss-Markov process and SINS/GNSS integration filter with 15 parameters state vector were given out. The results of Magnetometers-aided SINS navigation simulation showed that the Magnetometers-aided SINS can effectively inhibit the drift of SINS attitude, but couldn't obviously improve the precision of position and velocity. The results of Magnetometers/SINS/GNSS integration simulation showed that the precision of velocity and position were improved greatly, and the attitude accuracy was quite equal to the measuring accuracy of Magnetometers-aided SINS. Therefore the Magnetometers/SINS/GNSS integrated navigation method is an effective solution of low-cost navigation under high dynamic circumstances.

A novel mesocellular carbon foam (MSU-FC) with a large pore size and a three-dimensional porous structure for the oral delivery of poorly water-soluble drugs was prepared. The goal of this study was to improve in vitro dissolution and in vivo absorption of celecoxib (CEB), a model drug, by means of novel carbon-based nanoparticles prepared from the MSU-FC matrix. The MSU-FC matrix was synthesized by an inverse replica templating method using mesocellular silica template. A solvent immersion/evaporation method was used to load the drug molecules. The drug-loaded nanoparticles were characterized for morphology, surface area, particle size, mesoporous structure, crystallinity, solubility and dissolution. The effect of MSU-FC on cell viability was measured using the MTT conversion assay. Furthermore, the oral bioavailability of CEB-loaded MSU-FC in fasted rats was compared with that of the marketed product. Our results demonstrate that CEB incorporation into the prepared MSU-FC resulted in an approximately 9-fold increase in aqueous solubility in comparison with crystalline CEB. MSU-FC produced accelerated immediate release of CEB in comparison with crystalline CEB (pure CEB powder or marketed formulation) and the drug-loaded conventional mesoporous carbon particles. The relative bioavailability of CEB for CEB-loaded MSU-FC was 172%. In addition, MSU-FC nanoparticles exhibited very low toxicity. The MSU-FC nanomatrix has been shown to be a promising drug delivery vehicle for improving the dissolution and biopharmaceutical characteristics of poorly water-soluble drugs.

The investment of high-tech projects is characterized with high risk and huge profit, so a scientific and accurate risk evaluation is of importance to make decision. Based on the analysis of the indicators influencing the investment risk, a typical sample set was chosen according to the quantitative score results from the experts. After training, a random forests regression model was established to comprehensively evaluate the investment risk. The assessment result from a case shows the model not only can give a correct rank to the unknown samples, but also give the contribution degree and importance of the indicators. Subsequently, aimed at the leading model parameters, many tests were done to illustration their impact on the output results of the model. Finally, the importance of variables was analyzed, and was compared with that of projection pursuit model. The above results show it has stronger adaptability and robustness.

The dominant sources of phase error in a GPS INS-aided PLL consist of the statistical part and the deterministic part, it is same to a GPS INS-aided FLL. The effects of two type sources are quantified and error models are built to evaluate tracking performance. The results of this research show that the INS-aided FLL performs better than the INS-aided PLL. The minimum C/N0 is 27.7dB-Hz for the third order PLL, 25dB-Hz for the INS-aided second order PLL and 17.1B-Hz for the INS-aided second order FLL(IFLL2) when the maximum value of line-of-sight jerk is 10g/s, so IFLL2 is more suitable for high dynamic receiver.

The high-magnetic-field tensiometer (HMFT) has been developed to measure surface tensions of liquids in high magnetic field based on the ring method. The HMFT was composed of three parts: weighing system, liquid circulatory system, and supporting system. Some improvements for the conventional tensiometer were made in order to overcome the magnetic effects. The surface tension of acetone was measured using the HMFT. The results showed that the surface tension of acetone linearly varied with the magnetic field intensity and increased by 0.69 mN m(-1) or 2.9% in the magnetic field of 10 T. The HMFT could better determine the surface tension of liquids with and without the magnetic field and it provided a simple and practical way to measure the surface tension of liquids at room temperature in a high magnetic field.

Parameter identification is a key step in establishing kinetic models. Aimed at the above problem, it can be transformed into an optimization problem by constructing objective function that minimizes simulation errors. In this study, a novel swarm intelligence optimization algorithm-artificial bee colony algorithm is used. In the experiments, each variable is optimized according to its own reasonable scope. Then, two examples of kinetic models are analyzed and their computation results are compared with that of modified genetic algorithm, standard particle swarm optimization and its modified algorithms. The results show that artificial bee colony algorithm has good adaptability to various problems and better optimization precision. Moreover, it needs few control parameters of algorithm. So it is an effective optimization method.

When the carrier to do a high dynamic motion, it will lead the tracking error to increase, then the degree of nonlinearity of the detector will become large and the equivalent gain response will reduce, so it may lead the satellite signal to loss lock. This paper studies the simulation system of GPS/INS ultra-tight integration under high dynamic environment, it simulates two kinds of dynamic models and the results show the superiority of ultra-tight integration. When the GPS single interrupted, it can continue tracking by INS and it’s able to quickly restore the tracking when signal recovery. Ultra-tight integration also provides a possible for GPS anti-jamming technology.

In order to ensure the high positioning precision of GPS land survey device and uploading the investigating data to data central real time, the paper analyses the advantages and disadvantages of several wireless communication technique in common use. And a data transmission system used in GPS land survey device is designed and developed based on GPRS. The results of lots of tests and applications show the feasibility and reliability of the data transmission system.

Objective: A system for real-time pyrosequencing by biolumino-metric assay coupled with a photodiode array is presented. The approach is based on the detection of DNA polymerase activity by an enzymatic luminometric inorganic pyrophosphate (PPi) detection assay. It is designed to offer a convenient pyrosequencing-based platform for DNA sequencing with low cost and simple structure. Method: Together with the automated dNTPs micro-dispensers, a photoelectric conversion circuit with high sensitive photodiode S1133-01 and ultra-low bias current monolithic operational amplifier OPA129 is chosen to detect the luminometric, monitoring the ATP production continuously. The signal to noise ratio is improved efficiently by routing PCB and shielding carefully. Results: A C14 standard light source is selected to compare the sensitivity of the system to the photomultiplier tubes (PMT). The results show that the magnification of the circuits is ten times higher than the PMT, which is sufficient for detecting the DNAs as small as 10 fmol. Four different type of dNTPs are injected into the reaction cell in turn and the peak of luminescence illuminates the result, which is coinciding with the commercial system. Conclusion: The system is small, simple and inexpensive, which is enough for real-time pyrosequencing. But there are many works to do to construct the fast and high-flux DNA sequencing system.

AlgoSketch is a pen-based system for entering and editing mathematics. It supports interactive computation and early-stage mathematical algorithm design. In its paper-like environment, mathematical expressions can be entered anywhere on the page. Recognition and computational feedback are given in real time. We present results of a formative user evaluation of AlgoSketch, examining its applicability as a new interaction paradigm and users' overall experience with its mathematical entry, feedback, and computational support. Using a goal, question metric (GQM) framework, we evaluated AlgoSketch using efficiency, effectiveness, and satisfaction metrics. Logging data was supported by a post-questionnaire and anecdotal data. Results indicate acceptance of the AlgoSketch paradigm; strong potential for workplace utility, and a need for better mathematical expression recognition.

A study was conducted in Rakai Uganda to evaluate the urine HIV-1 test. 222 subjects provided paired concurrent urine and serum samples at a single study visit between 1996 and 1997. The samples were assayed for HIV-1 using Calypte HIV-1 urine enzyme immunoassay (EIA) with Western blot (WB) confirmation and sera were tested by EIA and WB. Masked assays were prepared on stored refrigerated urine at Johns Hopkins University (JHU) and on fresh specimens at the Rakai Project laboratory. The sensitivity and specificity of the urine assay were determined using serum EIA and WB assay results as the reference test. Out of the 96 serum HIV-positive results 92 were detected by urine EIA/WB giving a sensitivity of 95.8%. Of the 94 fresh urine samples all were positive on EIA and confirmed by WB giving a sensitivity of 100%. Among serum HIV-negative subjects all frozen urine samples were negative at JHU and 97.7% of fresh samples were negative at RP. The differences in sensitivity and specificity between the fresh and frozen samples were not statistically significant. In conclusion the results indicated that the Calypte urine HIV-1 EIA/WB is sensitive and specific as compared with the testing of serum samples.

We present an online system for recognizing handwritten mathematical matrices in the context of an interactive computational tool called MathPaper. Automatic segmentation and recognition of multiple expressions are supported based on a spacing algorithm that leverages recognized symbol identities, sizes, and relative locations of individual symbols. Matrices with ellipses can be recognized and instantiated with non-ellipsis elements. Both well- and non-well-formed matrices can also be recognized. Matrix elements can be any general mathematical expressions including imbedded matrices. Our recognizer also addresses the poor column alignment problem of handwritten matrices, and allows for slight horizontal overlaps between elements in neighboring columns and different rows.

Projection pursuit was a reducing dimensions treatment method. It was widely used to make the transition from high dimensional problem to one dimensional problem by projection direction. It was usually difficult to search the best projection direction, however it could be solved by an optimization question. Aimed at the prematurity and stagnancy shortages of basic ant colony, some improved countermeasures were put forward. Simulative result indicated that it was applicable and effective to solve the above optimization question based on improved ant colony algorithm.

Efficient recognition of haptic data such as 3D motion capture data and sign language sensory data can have wide applications in the interactive computer animation and sign language automatic translation areas. For this purpose, we propose a similarity measure for multi-attribute haptic data, a new form of multimedia signal. The proposed similarity measure, based on singular value decomposition, captures the most important features of the signal data, allows for different signal generating rates and reasonable variations in similar signals. Experiments with real life and synthetic data demonstrate that the proposed similarity measure can capture the similarities of motions with different speeds and different lengths and can have up to 100% recognition rates.

This paper proposes a classification-based approach to segmenting and recognizing patterns in motion signals. Feature vectors are extracted based on singular value decomposition (SVD) for classification. Multi-class support vector machine (SVM) classifiers with class probability estimates are explored for segmenting and recognizing motion streams. Experiments show that the proposed approach can find patterns in the multi-attribute motion streams with high accuracy

Content-based retrieval of 3D human motion capture data has significant impact in different fields such as physical medicine, rehabilitation, and animation. This paper develops an efficient indexing approach for 3D motion capture data, supporting queries involving both sub-body motions (e.g., Find similar knee motions) as well as whole-body motions. The proposed indexing structure is based on the hierarchical structure of the human body segments consisting of independent index trees corresponding to each sub-part of the body. Each level of every index tree is associated with the weighted feature vectors of a body segment and supports queries on sub-body motions and also on whole-body motions. Experiments show that up to 97% irrelevant motions can be pruned for any kind of motion query while retrieving all similar motions, and one traversal of the index structure through all index trees takes on an average 15 μsec with the existence of motion variations.

Recognition of motion streams such as data streams generated by different sign languages or various captured human body motions requires a high performance similarity measure. The motion streams have multiple attributes, and motion patterns in the streams can have different lengths from those of isolated motion patterns and different attributes can have different temporal shifts and variations. To address these issues, this paper proposes a similarity measure based on singular value decomposition (SVD) of motion matrices. Eigenvector differences weighed by the corresponding eigenvalues are considered for the proposed similarity measure. Experiments with general hand gestures and human motion streams show that the proposed similarity measure gives good performance for recognizing motion patterns in the motion streams in real time.

Haptic data such as 3D motion capture data and sign language animation data are new forms of multimedia data. The motion data is multi-attribute, and indexing of multi-attribute data is important for quickly pruning the majority of irrelevant motions in order to have real-time animation applications. Indexing of multi-attribute data has been attempted for data of a few attributes by using R-tree or its variants after dimensionality reduction. In this paper, we exploit the singular value decomposition (SVD) properties of multi-attribute motion data matrices to obtain one representative vector for each of the motion data matrices of dozens or hundreds of attributes. Based on this representative vector, we propose a simple and efficient interval-tree based index structure for indexing motion data with large amount of attributes. At each tree level, only one component of the query vector needs to be checked during searching, comparing to all the components of the query vector that should get involved if an R-tree or its variants are used for indexing. Searching time is independent of the number of pattern motions indexed by the tree, making the index structure well scalable to large data repositories. Experiments show that up to 91∼93% irrelevant motions can be pruned for a query with no false dismissals, and the query searching time is less than 30 μ s with the existence of motion variations.

In this work, we focus on fast and efficient recognition of motions in multi-attribute continuous motion sequences. 3D motion capture data, animation motion data, and sensor data from gesture sensing devices are examples of multi-attribute continuous motion sequences. These sequences have multiple attributes rather than only one attribute as time series data has. Motions can have different rates and durations, and the resulting data can thus have different lengths. Also, motion data can have noises due to transitions between successive motions. Hence, traditional distance measuring approaches used for time series data (such as Euclidean distances or dynamic time-warped distances) are not suitable for recognition in multi-attribute motion sequences. Hence, we have defined a similarity measure based on the analysis of singular value decomposition (SVD) properties of similar multi-attribute motions. A five-phase algorithm has then been proposed that gives good pruning power by exploiting the proximity of continuous motion data. We experimented this algorithm with data from different sources: 3D motion capture devices, animation motions, and CyberGlove gesture sensing device. These experiments show that our algorithm can segment and recognize long motion streams with high accuracy and in real time without knowing beforehand the number of motions in a stream.

Scheduler and switching fabric are two major hardware components of a cell switch. For a switch using a nonblocking switching fabric, the performance of the switch depends on the performance of its cell scheduler. We introduce the concepts of relative and universal scheduler scalabilities. Informally, a scheduler is relatively scalable with respect to a switching fabric if its structure is not more complex than the structure of its associated non-blocking switching fabric. A scheduler is universally scalable if its structural complexity is not larger than the structural complexity of any non-blocking switching fabric. Based on algorithm-hardware codesign, we present a universally scalable scheduler with O(N logN) interconnection complexity. We show by simulation that the performance of the proposed scheduler is almost the same as non-scalable schedulers.

The objective was to determine HIV prevalence, symptomatology and mortality among adult heads and non-heads of households, in order to assess the burden of HIV on households. It was a community study of 11,536 adults aged 15-59, residing in 4,962 households in 56 villages, Rakai district, Uganda. First, 4,962 heads and 6,574 non-heads of households were identified from censuses. Interviews were then used to determine socio-demographic/behavioural characteristics. HIV seroprevalence was diagnosed by two EIAs with Western blot confirmation. The adjusted odds ratio (OR) and 95% confidence intervals (CI) of HIV infection in household heads and non-heads were estimated by multivariate logistic regression. Age-adjusted mortality was also assessed. HIV prevalence was 16.9% in the population, and 21.5% of households had at least one HIV-infected person (0.0001). HIV prevalence was higher among heads than non-heads of households (21.5 and 13.3%, respectively, OR=1.79; CI 1.62-1.97). Most household heads were males (70.5%), and HIV prevalence was 17.8% among male heads compared with 6.6% in male non-heads of households (OR=2.31; CI 1.65-2.52). Women heading households were predominantly widowed, separated or divorced (64.4%). HIV prevalence was 30.5% among female heads, compared with 15.6% in female non-household heads (OR=1.42; CI 1.15-1.63). Age-adjusted mortality was significantly lower among male household heads than non-heads, both for the HIV-positive (RR=0.68) and HIV-negative men (RR=0.63). Among women, HIV-negative female household heads had significantly higher mortality than HIV-uninfected female non-heads (RR=1.72). HIV disproportionately affects heads of households, particularly males. Mortality due to AIDS is likely to increase the proportion of female-headed households, and adversely affect the welfare of domestic units.

A random sample of 960 women aged 15-59 years enrolled in a population-based study in rural Uganda were asked to provide self-collected vaginal swabs for human papillomavirus (HPV) testing by hybrid capture assay. The intensity of HPV infection was assessed by the relative light unit (RLU) ratio in the specimen-to-positive control (PC) ratio. In total, 898 women (93%) provided a swab and 737 provided serum for human immunodeficiency virus type 1 (HIV-1) determination. HPV prevalence was 16.7% and was highest in younger women. HIV-1 prevalence was 17.8%. HPV prevalence was 44.3% in HIV-positive and 10.2% in HIV-negative women (rate ratio, 5.36; 95% confidence interval, 3.81-7.54). The intensity of HPV infection was significantly greater among HIV-positive than HIV-negative women (54.4 vs. 11.1 RLU/PC; P = .026); intensity of infection was highest in women aged

We examined the association between education and prevalent HIV-1 infection in the Rakai district, rural Uganda based on a cross-sectional analysis of a population-based cohort. In 1990, 1397 men and 1705 women aged 13 years and older, were enrolled in 31 randomly selected communities. Strata were comprised of main road trading centres, secondary road trading villages and rural villages. Sociodemographic and behavioural data were obtained by interview and serum for HIV serostatus were obtained in the home. The analysis examines the association between sex-specific prevalent HIV infection and educational attainment, categorized as secondary, primary or none. The odds ratios (ORs) and 95% confidence intervals (95% CIs) of HIV infection were estimated, using no education as the referent group. Higher levels of education were associated with a higher HIV seroprevalence in bivariate analyses (OR 2.7 for primary and 4.1 for secondary education, relative to no education). The strength of the association was diminished but remained statistically significant after multivariate adjustment for sociodemographic and behavioural variables (adjusted OR of HIV infection 1.6 (95% CI: 1.2-2.1)) for primary education and 1.5 (95% CI: 1.0-2.2) for secondary education. Stratified multivariate analyses by place of residence indicated that the association between education and HIV prevalence was statistically significant in the rural villages, but not in the main road trading centres and intermediate trading villages. Educational attainment is a significant predictor of HIV risk in rural Uganda, in part because of risk behaviours and other characteristics among better educated individuals. Preventive interventions need to focus on better educated adults and on school-aged populations.This is a cross-sectional analysis of a population-based cohort study conducted to examine both the associations between educational attainment and HIV-1 serostatus as well as the relationship between education and other HIV risk factors in Rakai district, Uganda. A total of 3102 respondents (1397 men and 1705 women aged 13 years and older) completed a questionnaire and provided blood samples. The samples of community clusters was stratified into three strata: trading centers on main roads, intermediate trading villages on secondary roads, and rural agricultural villages with no roads or only minor road connection. Analysis has shown a consistent association between higher level of educational attainment and HIV-1 prevalence among the residents. The strength of the association was decreased but remained statistically relevant after multivariate adjustment for sociodemographic and behavioral variables [adjusted OR for HIV infection, 1.6 (95% CI, 1.2-2.1) for primary education and 1.5 (95% CI, 1.0-2.2) for secondary education]. Stratified multivariate analyses by place of residence showed that the relationship between education and HIV prevalence was markedly higher in the rural villages compared to the other two strata. Education provides greater economic resources, which facilitate behaviors that put individuals at greater risk. Analysis of findings suggests that HIV prevention strategies should focus on the more educated individuals, particularly in rural settings and among younger women.

To describe the design and first-round survey results of a trial of intensive sexually transmitted disease (STD) control to reduce HIV-1 incidence.Randomized, controlled, community-based trial in Rakai District, Uganda.In this ongoing study, 56 communities were grouped into 10 clusters designed to encompass social/sexual networks; clusters within blocks were randomly assigned to the intervention or control arm. Every 10 months, all consenting resident adults aged 15-59 years are visited in the home for interview and sample collection (serological sample, urine, and, in the case of women, self-administered vaginal swabs). Sera are tested for HIV-1, syphilis, gonorrhea, chlamydia, trichomonas and bacterial vaginosis. Following interview, all consenting adults are offered directly observed, single oral dose treatment (STD treatment in the intervention arm, anthelminthic and iron-folate in the control arm). Treatment is administered irrespective of symptoms or laboratory testing (mass treatment strategy). Both arms receive identical health education, condom and serological counseling services.In the first home visit round, the study enrolled 5834 intervention and 5784 control arm subjects. Compliance with interview, sample collection and treatment was high in both arms (over 90%). Study arm populations were comparable with respect to sociodemographic and behavioral characteristics, and baseline HIV and STD rates. The latter were high: 16.9% of all subjects were HIV-positive, 10.0% had syphilis, and 23.8% of women had trichomonas and 50.9% had bacterial vaginosis.Testing the effects of STD control on AIDS prevention is feasible in this Ugandan setting.An ongoing (1994-98) randomized, community-based trial in Uganda's Rakai District is assessing the assumption that intensive sexually transmitted disease (STD) control efforts result in marked declines in HIV/AIDS prevalence. Described, in this article, are the project design and findings of the first-round baseline survey. 56 communities were grouped into 10 clusters designed to encompass social/sexual networks and clusters within blocks were randomly assigned to the intervention or control arm. All consenting permanent residents of the district are visited in their homes at 10-month intervals where they are administered extensive questionnaires, provide urine and vaginal swab samples, and are offered mass treatment regardless of symptoms or laboratory testing (single oral dose STD treatment in the intervention arm and anthelmintics and iron folate in the control arm). Both groups receive identical health education, condom promotion, and serologic counseling services. In the first round of home visits, 5834 intervention and 5784 control arm subjects were enrolled, representing about 90% of eligible adults. The groups were comparable in terms of sociodemographic and behavioral characteristics and baseline rates of HIV and STDs. 16.9% of subjects were HIV-positive, 10.0% had syphilis, 23.8% of women had trichomonas, and 50.9% had bacterial vaginosis. Detailed STD assessment is expected not only to document the relationship between STD control and HIV, but also to identify which STDs confer the greatest population attributable risk for HIV transmission, facilitating targeted control efforts in the future.

This was a multicentred, prospective study of pregnancies among women using natural family planning. The women maintained natural family planning charts of the conception cycle, recording acts of intercourse and signs of ovulation (cervical mucus changes, including peak day and basal body temperature). Charts were used to assess the most probable day of insemination relative to the day of ovulation and length of the follicular phase of the cycle. The sex ratio (males per 100 females) for 947 singleton births was 101.5, not significantly different from the expected value of 105. The sex ratio did not vary consistently or significantly with the estimated timing of insemination relative to the day of ovulation, with the estimated length of the follicular phase or with the planned or unplanned status of the pregnancy. Although these findings may be affected by imprecision of the data, the study suggests that manipulation of the timing of insemination during the cycle cannot be used to affect the sex of offspring.In the context of ongoing debate over the determinants of sex ratio, the authors used data from a multinational study of pregnancies among natural family planning (NFP) users to investigate the association between timing of conception or follicular phase and length and the sex ratio at birth. They also explored whether a pregnancy's planned or unplanned status affects those associations. A multicenter, prospective study of pregnancies among women using NFP was conducted. The women maintained NFP charts of their conception cycles, recording acts of intercourse and signs of ovulation such as cervical mucus changes and basal body temperature. Charts were used to identify the most probable day of insemination relative to the day of ovulation and length of the follicular phase of the cycle. The sex ratio (number of males per 100 females) for 947 singleton births was 101.5, not significantly different from the expected value of 105. The sex ratio did not vary consistently or significantly with the estimated timing of insemination relative to the day of ovulation, with the estimated length of the follicular phase, or with the planned or unplanned status of the pregnancy. Study findings suggest that manipulating the timing of insemination during the cycle cannot be used to affect the sex of offspring.