Motor Eyes: Mechanical Platform for a Binocular Robotic Vision System

Stereoscopic vision systems require high computational power to perform image processing for 3D reconstruction of a scene. Synchronizing eye movements through mechanical coupling can reduce this processing power. To investigate this potential, the project team developed a mechanical platform for a binocular robotic vision system that uses stepper motors and slider linkages to achieve coupled pan, coupled tilt and coupled vergence eye movements. A prototype, controlled by an Arduino Uno, was constructed. The prototype achieved eye rotation speeds comparable to human saccadic eye motion and was capable of focusing on specified points with some position error caused by the prototype’s high sensitivity to misalignments of mechanical parts

Managing the Assistive Technology Resource Center

The goals of this project are to collect the previous 5 years of development research conducted by previous IQP projects and, in conjunction with newly developed plans,to implement a system to organize the lab’s facilities,to streamline the reuse of existing research, and to nourish the development of new projects. Following initial efforts to establish a firm operating foundation within the ATRC, our IQP will work to reestablish the assistive technology community at WPI through promotion of the Engineering Projects in Community Service (EPICS) club. Through this project, the club will both promote the ATRC and assistive technology program at WPI and provide students with service oriented outreach opportunities where they may gain experience solving actual problems

High rate of virological failure and low rate of switching to second-line treatment among adolescents and adults living with HIV on first-line ART in Myanmar, 2005-2015.

BACKGROUND: The number of people living with HIV on antiretroviral treatment (ART) in Myanmar has been increasing rapidly in recent years. This study aimed to estimate rates of virological failure on first-line ART and switching to second-line ART due to treatment failure at the Integrated HIV Care program (IHC). METHODS: Routinely collected data of all adolescent and adult patients living with HIV who were initiated on first-line ART at IHC between 2005 and 2015 were retrospectively analyzed. The cumulative hazard of virological failure on first-line ART and switching to second-line ART were estimated. Crude and adjusted hazard ratios were calculated using the Cox regression model to identify risk factors associated with the two outcomes. RESULTS: Of 23,248 adults and adolescents, 7,888 (34%) were tested for HIV viral load. The incidence rate of virological failure among those tested was 3.2 per 100 person-years follow-up and the rate of switching to second-line ART among all patients was 1.4 per 100 person-years follow-up. Factors associated with virological failure included: being adolescent; being lost to follow-up at least once; having WHO stage 3 and 4 at ART initiation; and having taken first-line ART elsewhere before coming to IHC. Of the 1032 patients who met virological failure criteria, 762 (74%) switched to second-line ART. CONCLUSIONS: We found high rates of virological failure among one third of patients in the cohort who were tested for viral load. Of those failing virologically on first-line ART, about one quarter were not switched to second-line ART. Routine viral load monitoring, especially for those identified as having a higher risk of treatment failure, should be considered in this setting to detect all patients failing on first-line ART. Strategies also need to be put in place to prevent treatment failure and to treat more of those patients who are actually failing

Long-term outcomes of second-line antiretroviral treatment in an adult and adolescent cohort in Myanmar.

BACKGROUND: Myanmar has a high burden of Human Immunodeficiency Virus (HIV) and second-line antiretroviral treatment (ART) has been available since 2008 in the public health sector. However, there have been no published data about the outcomes of such patients until now. OBJECTIVE: To assess the treatment and programmatic outcomes and factors associated with unfavorable outcomes (treatment failure, death and loss to follow-up from care) among people living with HIV (aged ≥ 10 years) receiving protease inhibitor-based second-line ART under the Integrated HIV Care Program in Myanmar between October 2008 and June 2015. DESIGN: Retrospective cohort study using routinely collected program data. RESULTS: Of 824 adults and adolescents on second-line ART, 52 patients received viral load testing and 19 patients were diagnosed with virological failure. However, their treatment was not modified. At the end of a total follow-up duration of 7 years, 88 (11%) patients died, 35 (4%) were lost to follow-up, 21 (2%) were transferred out to other health facilities and 680 (83%) were still under care. The incidence rate of unfavorable outcomes was 7.9 patients per 100 person years follow-up. Patients with a history of injecting drug use, with a history of lost to follow-up, with a higher baseline viral load and who had received didanosine and abacavir had a higher risk of unfavorable outcomes. Patients with higher baseline C4 counts, those having taken first-line ART at a private clinic, receiving ART at decentralized sites and taking zidovudine and lamivudine had a lower risk of unfavorable outcomes. CONCLUSIONS: Long-term outcomes of patients on second-line ART were relatively good in this cohort. Virological failure was relatively low, possibly because of lack of viral load testing. No patient who failed on second-line ART was switched to third-line treatment. The National HIV/AIDS Program should consider making routine viral load monitoring and third-line ART drugs available after a careful cost-benefit analysis

Extracting Patterns in Social Network by Means of Link Mining

The World Wide Web serves as a huge, widelydistributed, global information service center for news,advertisements, consumer information, financialmanagement, education, government, e-commerce, andmany other information services. The Web contains arich and dynamic collection of hyperlink informationwhich can access usage information and provide richsources for data mining. It is a highly dynamicinformation source and web service centers update theirweb pages regularly. Linkage information and accessare also updated frequently. This framework is thedistillation of broad search topics, through the discoveryof “authoritative” information sources on topics. Thisusing hubs, called HITS (Hyperlink-Induced TopicSearch) to find authoritative pages based on therelationship between a set of relevant authoritativepages and the set of “hub pages” that join them togetherin the link structure. This formulation has connections tothe eigenvectors of certain matrices associated with thelink graph. This HITS algorithm provides surprisinglygood search results for a wide range of query

Reverse pneumatic artificial muscles (rPAMs): Modeling, integration, and control.

Despite offering many advantages over traditional rigid actuators, soft pneumatic actuators suffer from a lack of comprehensive, computationally efficient models and precise embedded control schemes without bulky flow-control valves and extensive computer hardware. In this article, we consider an inexpensive and reliable soft linear actuator, called the reverse pneumatic artificial muscle (rPAM), which consists of silicone rubber that is radially constrained by symmetrical double-helix threading. We describe analytical and numerical static models of this actuator, and compare their performance against experimental results. To study the application of rPAMs to operate underlying kinematic linkage skeletons, we consider a single degree-of-freedom revolute joint that is driven antagonistically by two of these actuators. An analytical model is then derived, and its accuracy in predicting the static joint angle as a function of input pressures is presented. Using this analytical model, we perform dynamic characterization of this system. Finally, we propose a sliding-mode controller, and a sliding mode controller augmented by a feed-forward term to modulate miniature solenoid valves that control air flow to each actuator. Experiments show that both controllers function well, while the feed-forward term improves the performance of the controller following dynamic trajectories

Factors associated with long turnaround time for early infant diagnosis of HIV in Myanmar

Background: A previous review of early infant diagnosis (EID) using polymerase chain reaction technology (PCR) under integrated HIV care (IHC) program in Myanmar revealed a low uptake of timely (within 6 to 8 weeks of babies’ age) EID and a long turnaround time (TAT) of receiving results. Objective: This study aimed to determine the proportion and factors associated with the composite outcome of a long TAT (≥7 weeks; from sample collection to receipt of result by mother) or nonreceipt of result among HIV-exposed babies whose blood samples were collected for PCR at <9 months of age under the IHC program, Myanmar (2013–15). Methods: Cohort study involving record review of routinely collected data. A predictive Poisson regression model with robust variance estimates was fitted for risk factors of long TAT or nonreceipt of result. Results: Blood samples of 1 000 babies were collected; among them, long TAT or nonreceipt of results was seen in 690 (69%), and this was more than 50% across all subgroups. Babies with a mother’s CD4 count of 100–350 cells/mm3 at enrollment [adjusted RR (0.95 confidence intervals, CI): 0.8 (0.7, 0.9)] had a 20% lower risk of long TAT or nonreceipt of results when compared with ≥350 cells/mm3. Distance between ART center and PCR facility ≥105 km [adjusted RR (0.95 CI): 1.2 (1.1, 1.4)], when compared with <105 km, was associated with 20% higher risk of long TAT or nonreceipt of results. Conclusions: The proportion of babies with long TAT or nonreceipt of result by the mother was high. Point-of-care testing for EID may reduce TAT/nonreceipt of results by the mother. Health system, laboratory, and logistic factors such as sample transportation, laboratory procedures, and result dispatching associated with long TAT should be further explored

Early infant diagnosis of HIV in Myanmar: call for innovative interventions to improve uptake and reduce turnaround time

Background: In collaboration with the national AIDS program, early infant diagnosis (EID) is implemented by Integrated HIV Care (IHC) program through its anti-retroviral therapy (ART) centers across 10 cities in five states and regions of Myanmar. Blood samples from the ART centers are sent using public transport to a centralized PCR facility. Objectives: Among HIV-exposed babies 8 weeks of age) or no blood sample collection for EID. Methods: Retrospective cohort study involving record review. A predictive poisson regression model with robust variance estimates was fitted for risk factors of delayed or no sample collection. Results: Of 1349 babies, 523 (39%) of the babies’ mothers were on ART before pregnancy. Timely uptake of EID (<8 weeks of age) was 47% (633/1349); sample collection was delayed in 27% (367/1349) and not done in 26% (349/1349) babies. Among samples collected (n = 1000), 667 results were received by the mother; 52 (5%) were HIV-infected; among them 42 (81%) were initiated on ART. Median (IQR) turnaround time from sample collection to result receipt by mother and time to initiate ART from result receipt by mother was 7 (4,12) and 8.5 (6,16) weeks, respectively. Mothers not on ART before pregnancy and distance of ART center from PCR facility (more than 128 km) were the risk factors of delayed or no sample collection. Conclusions: Improving provision of ART to mothers (through universal ‘test and treat’) is urgently required, which has the potential to improve the timely uptake of EID as well. Interventions to reduce turnaround times, like point of care EID testing and/or systematic use of mobile technology to communicate results, are needed

HIV Care Cascade among Prisoners of the Mandalay Central Prison in Myanmar: 2011–2018

Prisoners have a higher HIV prevalence and higher rates of attrition from care as compared with the general population. There is no published evidence on this issue from Myanmar. We assessed (1) HIV test uptake, HIV positivity, and enrollment in care among newly admitted prisoners between 2017 and 18 (2) Treatment outcomes among HIV-positive prisoners enrolled in care between 2011 and 18. This was a cohort study involving secondary analysis of program data. Among 26,767 prisoners admitted to the Mandalay Central Prison between 2017 and 2018, 10,421 (39%) were HIV-tested, 547 (5%) were HIV-positive, and 376 (69%) were enrolled in care. Among the 1288 HIV-positive prisoners enrolled in care between 2011 and 2018, 1178 (92%) were started on antiretroviral therapy. A total of 883 (69%) were transferred out (post-release) to other health facilities, and among these, only 369 (42%) reached their destination health facilities. The final outcomes (censored on 30 June 2019) included the following: (i) Alive and in care 495 (38%), (ii) death 138 (11%), (iii) loss to follow-up 596 (46%), and (iv) transferred out after reaching the health facilities 59 (5%). We found major gaps at every step of the HIV care cascade among prisoners, both inside and outside the prison. Future research should focus on understanding the reasons for these gaps and designing appropriate interventions to fill these gaps