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Tuberculosis control in Sindh, Pakistan: Critical analysis of its implementation
No full textSummaryTuberculosis (TB) remains one of the main health problems despite preventive and control measures that have been taken in the past few decades. It is responsible for almost 8.8 million cases and 1.4 million deaths around the world. Lack of access to TB services is a barrier for empowering TB patients. In a country like Pakistan, controlling TB has become a challenge because of the lack of private sector involvement in a National Tuberculosis Control Program (NTP). Therefore, collaboration is needed between public, private and government sectors in treating TB as well as in improving the quality of the health care system
An enhanced disk averaged CFD model for the simulation of horizontal axis tidal turbines
No full textAbstractSimulating fully resolved Horizontal Axis Tidal Turbine (HATT) geometry for a time period great enough to resolve a fully developed wake, and accurately predict power and thrust characteristics, is computationally very expensive. The BEM-CFD method is an enhanced actuator disk and is able to reduce the computational cost by simulating a time averaged downstream velocity field. Current implementations fall short of accurately determining tip losses, which are a function of the hydrofoil geometry. This work proposes a method of addressing this shortfall by modifying the angle of attack to conform to the constraints outlined in Prandtl's lifting line theory, i.e. the zero lift angle of attack at the hydrofoil tip. The revised model is compared to existing BEM-CFD methods and validated against experimental data. The revised BEM-CFD method presented in this work shows a significant improvement over previous BEM-CFD methods when predicting power and thrust. The coefficient of power is reduced from 0.57 (approx. 30% above experiment) to 0.44 (approx. 3% above experiment). An increase in turbulence intensity in the rotor region, in particular at the wake boundary, improves the recovery of the wake without the addition of empirical turbulence source terms. Good correlation with experimental results for power, thrust and wake prediction, is observed. The model may also be applied to wind turbines
Neuronal correlates of continuous manual tracking under varying visual movement feedback in a virtual reality environment
No full textAbstractTo accurately guide one's actions online, the brain predicts sensory action feedback ahead of time based on internal models, which can be updated by sensory prediction errors. The underlying operations can be experimentally investigated in sensorimotor adaptation tasks, in which moving under perturbed sensory action feedback requires internal model updates. Here we altered healthy participants’ visual hand movement feedback in a virtual reality setup, while assessing brain activity with functional magnetic resonance imaging (fMRI). Participants tracked a continually moving virtual target object with a photorealistic, three-dimensional (3D) virtual hand controlled online via a data glove. During the continuous tracking task, the virtual hand's movements (i.e., visual movement feedback) were repeatedly periodically delayed, which participants had to compensate for to maintain accurate tracking. This realistic task design allowed us to simultaneously investigate processes likely operating at several levels of the brain's motor control hierarchy. FMRI revealed that the length of visual feedback delay was parametrically reflected by activity in the inferior parietal cortex and posterior temporal cortex. Unpredicted changes in visuomotor mapping (at transitions from synchronous to delayed visual feedback periods or vice versa) activated biological motion-sensitive regions in the lateral occipitotemporal cortex (LOTC). Activity in the posterior parietal cortex (PPC), focused on the contralateral anterior intraparietal sulcus (aIPS), correlated with tracking error, whereby this correlation was stronger in participants with higher tracking performance. Our results are in line with recent proposals of a wide-spread cortical motor control hierarchy, where temporoparietal regions seem to evaluate visuomotor congruence and thus possibly ground a self-attribution of movements, the LOTC likely processes early visual prediction errors, and the aIPS computes action goal errors and possibly corresponding motor corrections
Prevalence of intimate partner violence in Spain: A national cross-sectional survey in primary care
No full textAbstractObjectives(1) To analyze the prevalence of Intimate Partner Violence by types. (2) To examine the relationship between sociodemographic characteristics and Intimate Partner Violence.DesignCross-sectional study using a self-administered questionnaire.SettingPrimary Healthcare centers in Spain.Participants10,322 women (18–70 years) attending Primary Healthcare centers.Main measurementsA compound index was calculated based on frequency, types, and duration of Intimate Partner Violence. Multivariable adjusted logistic regression models were used to identify the sociodemographic factors, which were independently associated with each Intimate Partner Violence category.ResultsThe prevalence of Intimate Partner Violence was 24.8%. For the physical only category, no differences were observed regarding education or employment status, and women with the highest income have less risk. For the psychological only category, no differences were observed according to the income level. The risk increases as the education level decreases, and the greatest frequency of only psychological Intimate Partner Violence was observed in women who were unemployed or students. For both the physical and psychological category of Intimate Partner Violence, a clear risk increase is observed as income and education levels decrease. Retired women showed the highest frequency of this violence category.ConclusionThe results show that Intimate Partner Violence affects women of all social strata, but the frequency and Intimate Partner Violence category will vary according to the socio-economic
Spherical subjective refraction with a novel 3D virtual reality based system
No full textAbstractPurposeTo conduct a clinical validation of a virtual reality-based experimental system that is able to assess the spherical subjective refraction simplifying the methodology of ocular refraction.MethodsFor the agreement assessment, spherical refraction measurements were obtained from 104 eyes of 52 subjects using three different methods: subjectively with the experimental prototype (Subj.E) and the classical subjective refraction (Subj.C); and objectively with the WAM-5500 autorefractor (WAM). To evaluate precision (intra- and inter-observer variability) of each refractive tool independently, 26 eyes were measured in four occasions.ResultsWith regard to agreement, the mean difference (±SD) for the spherical equivalent (M) between the new experimental subjective method (Subj.E) and the classical subjective refraction (Subj.C) was −0.034D (±0.454D). The corresponding 95% Limits of Agreement (LoA) were (−0.856D, 0.924D). In relation to precision, intra-observer mean difference for the M component was 0.034±0.195D for the Subj.C, 0.015±0.177D for the WAM and 0.072±0.197D for the Subj.E. Inter-observer variability showed worse precision values, although still clinically valid (below 0.25D) in all instruments.ConclusionsThe spherical equivalent obtained with the new experimental system was precise and in good agreement with the classical subjective routine. The algorithm implemented in this new system and its optical configuration has been shown to be a first valid step for spherical error correction in a semiautomated way
Local impacts of industrial tree plantations: An empirical analysis in Indonesia across plantation types
No full textAbstractThe values ascribed to industrial tree plantations are often controversial. Hence knowledge of their perceived impacts is important for improving their integration in rural landscapes. In 2016 we conducted household surveys with 606 respondents living in villages adjacent to acacia, teak and pine plantations across three islands in Indonesia (Java, Borneo, Sumatra). Results show that perceptions toward pine and teak plantations tend to differ from those toward acacia pulpwood plantations in several ways. Pine and teak plantations are perceived to have a higher number and variety of benefits and services, a higher number of positive impacts, a better environmental record, and to present more opportunities to local people for use of plantation land and products for improving rural livelihoods. In addition, we find that villagers around acacia pulpwood plantations tend to seek economic development and infrastructure to open up remote areas, yet their expectations were often only partially met. Recommendations from our analysis include: the role of the State in plantations must be clarified and potentially reinforced; the role of institutions as intermediaries is fundamental; and contributions by communities to design of management plans should be accommodated
How accurate is our misinformation? A randomized comparison of four survey interview methods to measure risk behavior among young adults in the Dominican Republic
No full textAbstractObjectiveTo identify the most effective survey interview method for measuring risk behavior among young adults in the Dominican Republic.Methods1200 young adults were randomized to one of four different survey interview methods: two interviewer-assisted methods [face-to-face interview (FTFI), and computer-assisted telephone interview (CATI)], and two self-administered methods [self-administered interview (SAI), and audio computer-assisted, self-administered interview (ACASI)]. Youth were asked about a wide range of youth-specific risk behaviors, including violence, substance use, as well as sexual and reproductive health. Quality of data collected was examined by looking at how the survey was administered, including identifying two sources of errors that typically threaten data quality11This study assumes that bias does not change with sample size. In order to increase the sample size, the data collection period was extended, leaving everything else unchanged. It is, therefore, assumed that the decreasing effects of the learning curve are negligible.: (i) errors at the individual level with regards to survey methodology performance and cognitive difficulties [measured with the Response Consistency Index (RCI)]; and (ii) errors at the aggregate level (how desirability bias, interviewer gender, and interview privacy settings affect responses).ResultsNo statistically significant differences in participant non-response rates were found at the individual level across all survey interview methods. At the individual question level, self-completion methods generated higher non-response and error rates than assisted methods. The SAI method showed the poorest performance of all four methods in terms of non-response rate (1.6%22Percentage of data with non-response values at the question level.) and RCI (83.0%).At the aggregate level, the prevalence of several key risk indicators was statistically significant between methods. Using means-adjustment for covariates (μ), sexual and reproductive health-related indicators were found to have statistically significant differences among methods. Interviewer-assisted methods reported higher prevalence compared to self-administered methods. For example, when interviewer-assisted FTFI was administered, higher prevalence was reported for indicators, such as Ever Had Sex (for both genders), Safe Casual Sex (for males), and Transactional Sex (for males) than self-administered ACASI methods. On the contrary, when a SAI self-administered method was applied, results showed higher prevalence rates of concurrency among women, (e.g., sexual activity with multiple partners that overlap in time).The study also suggests that there were differences in survey interview methods used when looking at drug and alcohol use indicators. The direction of bias differed between drug use and alcohol consumption indicators. Respondents using ACASI self-administered methods had a higher Drug Use prevalence. However, FTFI reported a higher prevalence of Binge Drinking among female participants, as compared to ACASI.Additionally, the research team found a strong interaction with interviewer gender. In FTFI, affirmative responses to Sex with Same Gender questions were higher among men interviewed by women, than among men interviewed by men. The gender of the interviewer also seems to generate socially desirable response in violence risk-related indicators. That is the case for Victimization among males where the use of SAI increases the prevalence.Furthermore, this study suggests that whenever privacy during an interview was recorded as insufficient, women tended to report sexual initiation at almost a year younger than when responding with privacy.ConclusionsThe study's findings suggest that the degree to which a specific method improves the reporting of a particular risk behavior or set of behaviors is likely to be population specific. The study's results support the researchers’ initial hypothesis that higher prevalence estimates may be less valid than lower estimates in the Dominican Republic context, especially where some risk behaviors, like sexual activity, are normative and socially acceptable. More specifically, use of interviewer-assisted methods appears to significantly increase the reporting of socially-accepted behaviors, such as that both male and female populations over-report sensitive questions. Similarly, the level of privacy during the interview and interviewer’s gender may have an important effect on responses, and this effect depends on the chosen survey interview method
On horizontal Hardy, Rellich, Caffarelli–Kohn–Nirenberg and p-sub-Laplacian inequalities on stratified groups
No full textAbstractIn this paper, we present a version of horizontal weighted Hardy–Rellich type and Caffarelli–Kohn–Nirenberg type inequalities on stratified groups and study some of their consequences. Our results reflect on many results previously known in special cases. Moreover, a new simple proof of the Badiale–Tarantello conjecture [2] on the best constant of a Hardy type inequality is provided. We also show a family of Poincaré inequalities as well as inequalities involving the weighted and unweighted p-sub-Laplacians
Synthetic iron complexes as models for natural iron-humic compounds: Synthesis, characterization and algal growth experiments
No full textAbstractA series of monomeric and dimeric FeIII complexes with O,O-; O,N-; O,S-coordination motifs has been prepared and characterized by standard analytical methods in order to elucidate their potential to act as model compounds for aquatic humic acids. Due to the postulated reduction of iron in humic acids and following uptake by microorganisms, the redox behavior of the models was investigated with cyclic voltammetry. Most of the investigated compounds showed iron reduction potentials accessible to biological reducing agents. Additionally, observed reduction processes were predominantly irreversible, suggesting that subsequent reactions can take place after reduction of the iron center. Also the stability of the synthesized complexes in pure water and artificial seawater was monitored from 24h up to 21days by means of UV–Vis spectrometry. Several complexes remained stable even after 21days, showing only partially precipitation but some of them showed changes in UV–Vis spectra already after 24h which were connected to protonation/deprotonation processes as well as redox processes and degradation of the complexes. The ability to act as an iron source for primary producers was tested in algal growth experiments with two marine algae species Chlorella salina and Prymnesium parvum. Some of the compounds showed effects on the algal cultures, which are comparable with natural humic acids and better as for the samples kept under ideal conditions. Those findings help to understand which functional groups of humic acids could be responsible for the reversible iron binding and transport in aquatic humic substances
Current status of multi-detector row helical CT in imaging of adult acquired pancreatic diseases and assessing surgical neoplastic resectability
No full textAbstractBackgroundIt is usually hard to detect pancreatic lesions early as the pancreas lays retro peritoneum so it cannot be assessed during a routine physical exam. By the time a person has symptoms, the disease has already established morphological imaging CT changes.ObjectiveThe objective of our study was to clarify the role of multidetector computerized tomography (MDCT) in different adult acquired pancreatic diseases and assess the efficacy of surgical pancreatic tumors resectability preoperative.Materials & methodsThe study included thirty adult patients suspected to have pancreatic diseases (18 males and 12 females); their age range was 45–90years with a mean age of 68years. All patients underwent triple-phase multi-detector row CT using a 16-slice machine. The presence of inflammation, masses, and vascular invasion was evaluated and interpreted images were obtained during each phase. Results were compared with surgery, histopathology or follow-up.ResultsOf 30 patients, 15 had pancreatic malignancies (14 adenocarcinoma of which 6 were resectable and 8 were irresectable, 1 distant metastasis) proven at biopsy and/or surgery, 11 patients had pancreatitis (acute and chronic), three patients had cystic benign tumors (2 mucinous cystadenoma, 1 serous cystadenoma), and one patient had neuroendocrine tumor (insulinoma).ConclusionContrast enhanced multiphase pancreatic imaging by MDCT with its post processing techniques represents the imaging modality of choice for the diagnosis of different adult acquired pancreatic diseases