Energy- and Cost-Efficient Pumping Station Control

With renewable energy becoming more common, energy prices fluctuate more depending on environmental factors such as the weather. Consuming energy without taking volatile prices into consideration can not only become expensive, but may also increase the peak load, which requires energy providers to generate additional energy using less environment-friendly methods. In the Netherlands, pumping stations that maintain the water levels of polder canals are large energy consumers, but the controller software currently used in the industry does not take real-time energy availability into account. We investigate if existing AI planning techniques have the potential to improve upon the current solutions. In particular, we propose a light weight but realistic simulator and investigate if an online planning method (UCT) can utilise this simulator to improve the cost-efficiency of pumping station control policies. An empirical comparison with the current control algorithms indicates that substantial cost, and thus peak load, reduction can be attained

Implementation and effect of intensified case finding on diagnosis of tuberculosis in a large urban HIV clinic in Uganda: a retrospective cohort study.

BACKGROUND: Increased detection of tuberculosis (TB) using intensified or active case finding (ICF) is one of the cornerstones of the Stop TB Strategy, and contrasts with passive case finding (PCF) which relies on self-reported symptoms. There is no clear guidance on implementation strategies. We implemented ICF in addition to ongoing PCF in our large urban HIV clinic in July 2010 using a twice-daily announcement screen method by a trained peer educator, asking waiting patients to self-refer to a trained peer supporter for screening of TB symptoms. We sought to determine the associated effect on TB case detection. METHODS: Suspects were investigated by sputum smear, chest X-ray and ultrasound, if indicated. Routinely collected clinical and laboratory data were merged with the ICF register and TB clinic data for patients attending the clinic in 2010. We compared the yield of TB cases (defined as the prevalence of newly diagnosed TB cases in the screened population), the type of TB diagnosed and the total cost per TB case identified (in United States Dollars [USD]) for the period before and after ICF implementation. RESULTS: Of the 20,456 patients who visited the clinic in 2010, 614 were identified as TB suspects, 220 pre-ICF and 394 post-ICF (229 via PCF and 165 via ICF). The proportion diagnosed with TB dropped from 66% to 48% (60% in suspects identified through PCF and 31% through ICF). During the post-ICF period, TB suspects identified through ICF compared to PCF identification were more likely to be female, older, on ART and to have been enrolled in HIV care for a longer duration. The yield of combined PCF and ICF screening was 1.4% pre-ICF and 1.7% post-ICF with a cost per TB case identified of 12.29 USD and 21.80 USD, respectively. CONCLUSIONS: Implementation of ICF in a large HIV clinic yielded more TB suspects and cases, but substantially increased costs and was unable to capture the majority of TB suspects who were referred for diagnosis by clinicians through PCF. The overall yield of TB cases in a mature HIV clinic was low, although targeted screening of those recently enrolled in care may increase the yield

Exercise and heart transplantation. A review

Results of heart transplantation as therapy for end-stage cardiac diseases are encouraging not only because of actuarial survival curves but also because of the recovered quality of life for the heart transplant recipient. Although heart transplantation drastically improves the physical capacity of the patients, heart recipients still have a reduced maximal aerobic capacity compared to healthy people. Altered resting and exercise haemodynamics, due to cardiac denervation, are a common finding after orthotopic heart transplantation: increases in heart rate and stroke volume at exercise are first linked with the augmented venous return and later with the increased plasmatic noradrenaline level. Maximal heart rate and stroke volume are both reduced when compared to innervated heart. Reduced cardiac output response to exercise therefore results in early anaerobic metabolism, acidosis, hyperventilation and diminished physical capacity. In spite of an altered ventilatory adaptation to exercise, characterised by hyperpnoea in most transplant patients, ventilation is not the limiting factor for exercise in heart recipients without associated obstructive pulmonary disease. Endurance training restores lean tissue, decreases submaximal minute ventilation, increases peak work output, maximal ventilation and peak heart rate. Guidelines for prescribing exercise are not yet standardised dueto the limited number of studies on a sufficient cohort of heart recipients. Nevertheless, recommendations similar to those used for persons with coronary heart disease, with modifications due to the denervated heart, seem to be used. The cardiocirculatory and pulmonary capacity of heart transplant recipients allow them to undertake endurance sports activities such as walking, jogging, cycling and swimming, and these should be encouraged.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Renal responses to exercise in heart and kidney transplant patients

There is a lack of information about renal responses in heart and kidney transplant patients after intense physical exercise. Eleven heart and ten kidney trans plant recipients, as well as two control groups of healthy subjects, were given a maximum exercise test on a bicycle ergometer. One control group was also given a moderate load corresponding to the peak load of the kidney transplant group. Blood and urine samples were collected before and after exercise and assayed for lactate, creatinine, total protein, and albumin. The glomerular filtration rate remained stable at the end of exercise in the transplant patients, while there was a slight (17%) decrease in the control group. Albumin excretion rates after maximum exercise attained a mean of 237 μg min-1 in the control group and a mean of 45 and 16 μg min-1 respectively, in the heart and kidney groups. Postexercise proteinuria seemed to be related to the absolute intensity of the event, but kidney transplant patients showed a reduced effect as compared to heart transplant patients. We conclude that short-term, maximum exercise in heart and kidney transplant recipients is not detrimental to kidney function.SCOPUS: ar.jFLWINinfo:eu-repo/semantics/publishe

Risk of tuberculosis after antiretroviral treatment initiation: a comparison between efavirenz and nevirapine using inverse probability weighting

There is a high incidence of tuberculosis (TB) early after antiretroviral therapy (ART) initiation. This historical cohort study evaluated the association of efavirenz (EFV) compared to nevirapine (NVP) with post-ART TB among patients initiated on first-line ART from 2005 to 2009 in a large, urban HIV clinic in Uganda. Hazard ratios (HR) for developing TB were computed using multivariable Cox proportional hazards models with inverse weighting of the probability of being prescribed NVP or EFV (calculated by a multivariable logistic regression model), stratifying by baseline CD4+ T-cell count. Adjustment for time-updated CD4+ T-cell count, restriction of the analysis to patients remaining in follow-up and a TB-free survival analysis were performed as sensitivity analyses. ART was initiated in 5,797 patients; 66% were women with a mean age of 37 years (SD 9) and a median baseline CD4+ T-cell count of 117 cells/mm3 (IQR 43-182). Overall, 60% (n = 3,484) were initiated on NVP and 40% (n = 2,313) on EFV. In the first 2 years of ART, 377 patients developed TB. The use of EFV compared to NVP was independently associated with higher TB incidence in patients with a baseline CD4+ T-cell count < 100 cells/mm3 (HR 2.05 [95% CI 1.29, 3.27]; P = 0.003), but not at higher CD4+ T-cell counts (HR 0.71 [95% CI 0.39, 1.31]; P = 0.428). These estimates were robust to all sensitivity analyses. There was a higher incidence of TB in patients with baseline CD4+ T-cell counts < 100 cells/mm3 initiated on EFV compared to those initiated on NVP. Further research in a trial setting or a larger multisite observational cohort is needed to confirm these finding

Unrecognised tuberculosis at antiretroviral therapy initiation is associated with lower CD4+ T cell recovery

To investigate whether an unrecognised diagnosis of tuberculosis (TB) at the start of antiretroviral therapy (ART) influences subsequent CD4+ T cell (CD4) count recovery in an urban HIV clinic in Uganda. In a retrospective cohort study, a multivariable polynomial mixed effects model was used to estimate CD4 recovery in the first 96 weeks of ART in two groups of patients: prevalent TB (started ART while on TB treatment), unrecognised TB (developed TB within 6 months after start ART). Included were 511 patients with a median baseline CD4 count of 57 cells/mm(3) (interquartile range: 22-130), of whom 368 (72%) had prevalent TB and 143 (28%) had unrecognised TB. Compared with prevalent TB, unrecognised TB was associated with lower CD4 count recovery at 96 weeks: -22.3 cells/mm(3) (95% confidence interval -43.2 to -1.5, P = 0.036). These estimates were adjusted for gender, age, baseline CD4 count and the use of zidovudine-based regimen. Unrecognised TB at the time of ART initiation resulted in impaired CD4 recovery compared with TB treated before ART initiation. More vigilant screening with more sensitive and rapid TB diagnostics prior to ART initiation is needed to decrease the risk of ART-associated TB and sub-optimal immune reconstitutio

Integration of HIV and TB Services Results in Improved TB Treatment Outcomes and Earlier Prioritized ART Initiation in a Large Urban HIV Clinic in Uganda

Background: The World Health Organization recommends that treatment of tuberculosis (TB) in HIV-infected patients should be integrated with HIV care. In December 2008, a separate outdoor-integrated TB/HIV clinic was instituted for attendees of a large urban HIV clinic in Uganda. We sought to evaluate associated TB and HIV treatment outcomes. Methods: Routinely collected clinical, pharmacy, and laboratory data were merged with TB clinic data for patients initiating TB treatment in 2009 and with TB register data for patients in 2007. TB treatment outcomes and (timing of) antiretroviral therapy (ART) initiation in ART-naive patients [overall and stratified by CD4+ T cell (CD4) count] in 2007 and 2009 were compared. Nosocomial transmission rates could not be assessed. Results: Three hundred forty-six patients were initiated on TB treatment in 2007 and 366 in 2009. Median CD4 counts at TB diagnosis did not differ. TB treatment cure or completion increased from 62% to 68%, death or default decreased from 33% to 25% (P 250 cells per cubic millimeter (19% vs. 48%, P = 0.003). More patients were started on ART during TB treatment (94% vs. 78%, P <0.001). Moreover, the majority were now initiated during intensive phase (60% vs. 23%, P <0.001). Conclusions: Integration of TB and HIV care has led to improved TB treatment outcomes and earlier, prioritized ART initiation. This supports rollout of a fully integrated TB/HIV service delivery model throughout high-prevalence TB and HIV setting

Ventricular fibrillation waveform characteristics differ according to the presence of a previous myocardial infarction: A surface ECG study in ICD-patients

Background:\ud Characteristics of the ventricular fibrillation (VF) waveform reflect arrest duration and have been incorporated in studies on algorithms to guide resuscitative interventions. Findings in animals indicate that VF characteristics are also affected by the presence of a previous myocardial infarction (MI). As studies in humans are scarce, we assessed the impact of a previous MI on VF characteristics in ICD-patients.\ud \ud Methods:\ud Prospective cohort of ICD-patients (n = 190) with defibrillation testing at the Radboudumc (2010–2013). VF characteristics of the 12-lead surface ECG were compared between three groups: patients without a history of MI (n = 88), with a previous anterior (n = 47) and a previous inferior MI (n = 55).\ud \ud Results:\ud As compared to each of the other groups, the mean amplitude and amplitude spectrum area were lower, for an anterior MI in lead V3 and for an inferior MI in leads II and aVF. Across the three groups, the bandwidth was broader in the leads corresponding with the infarct localisation. In contrast, the dominant and median frequencies only differed between previous anterior MI and no history of MI, being lower in the former.\ud \ud Conclusions:\ud The VF waveform is affected by the presence of a previous MI. Amplitude-related measures were lower and VF was less organised in the ECG-lead(s) adjacent to the area of infarction. Although VF characteristics of the surface ECG have so far primarily been considered a proxy for arrest duration and metabolic state, our findings question this paradigm and may provide additional insights into the future potential of VF-guided resuscitative interventions