TimeTrader: Exploiting Latency Tail to Save Datacenter Energy for On-line Data-Intensive Applications

Datacenters running on-line, data-intensive applications (OLDIs) consume significant amounts of energy. However, reducing their energy is challenging due to their tight response time requirements. A key aspect of OLDIs is that each user query goes to all or many of the nodes in the cluster, so that the overall time budget is dictated by the tail of the replies' latency distribution; replies see latency variations both in the network and compute. Previous work proposes to achieve load-proportional energy by slowing down the computation at lower datacenter loads based directly on response times (i.e., at lower loads, the proposal exploits the average slack in the time budget provisioned for the peak load). In contrast, we propose TimeTrader to reduce energy by exploiting the latency slack in the sub- critical replies which arrive before the deadline (e.g., 80% of replies are 3-4x faster than the tail). This slack is present at all loads and subsumes the previous work's load-related slack. While the previous work shifts the leaves' response time distribution to consume the slack at lower loads, TimeTrader reshapes the distribution at all loads by slowing down individual sub-critical nodes without increasing missed deadlines. TimeTrader exploits slack in both the network and compute budgets. Further, TimeTrader leverages Earliest Deadline First scheduling to largely decouple critical requests from the queuing delays of sub- critical requests which can then be slowed down without hurting critical requests. A combination of real-system measurements and at-scale simulations shows that without adding to missed deadlines, TimeTrader saves 15-19% and 41-49% energy at 90% and 30% loading, respectively, in a datacenter with 512 nodes, whereas previous work saves 0% and 31-37%.Comment: 13 page

Metabolic syndrome: frequency and gender differences at an out - patient clinic

Objective: To determine the frequency of metabolic syndrome among patients attending an out-patient clinic of a teaching hospital and to compare the clinical features regarding metabolic syndrome among males and females.Study Design: Cross-sectional study.Place and Duration: Aga Khan University Hospital (AKUH), Executive and Family Medicine Clinics, from December 2004 to April 2005.Patients and Methods: All adults, above 25 years, attending the clinics for an executive check-up and giving informed consent were included in the study. Data was collected through a structured questionnaire administered to those eligible to participate. Metabolic syndrome was defined according to ATP-III guidelines.Results: There were 250 participants in this study. Mean age of study participants was 48.94 (SD10.62) years, while approximately two-thirds, 157 (62.8%), were male. Metabolic syndrome (those who had 3 or more risk factors) was present in 35.2% of adults. Fasting blood sugar level was raised in 36.4% of study participants while significant number of participants (78.8%) had a body mass index (BMI) \u3eor= 25 (p = 0.02).Conclusion: Frequency of metabolic syndrome was significantly high in this study with preponderance of males and prevalence similar to that observed in developed countries. Majority of patients had obesity and high fasting blood sugar levels. Males demonstrated higher levels of triglycerides and low levels of high-density lipoprotein (HDL) compared to females while blood pressure reading was observed to be the same in both males and females

Attributes of an effective clinical teacher: a survey on students\u27 and teachers\u27 perceptions

OBJECTIVE: To identify the attributes of effective clinical teacher, using a self-filled survey questionnaire, that students and faculty value most, and to compare the opinion of student and faculty regarding the same. STUDY DESIGN: Cross-sectional study.PLACE AND DURATION OF STUDY: The Aga Khan University Hospital (AKUH), Karachi from October 2006 to January 2007. Subject and Methods: Clinical faculty at AKUH and students in clinical years were included in this survey after taking their written informed consent. Data were collected through a structured questionnaire administered to all participants. Responses were compared.RESULTS: A total of 119 students in clinical years (3, 4 and 5) and 89 faculties involved in clinical teaching responded to the questionnaire. The most important attributes in faculty\u27s and students\u27 perspective were knowledge, interest in teaching and clinical competency. In students and faculty perspective, the fourth and fifth attributes were good communication skills and being non-judgmental. CONCLUSION: Students in clinical years and clinical teachers valued knowledge, interest in teaching and clinical competency as the most important attributes for an effective clinical teacher. There were various areas of agreement and disagreement between faculty and students about attributes of effective clinical teacher

Are family planning vouchers effective in increasing use, improving equity and reaching the underserved? An evaluation of a voucher program in Pakistan

Background: Low modern contraceptive prevalence rate and high unmet need in Pakistan aggravates the vulnerabilities of unintended pregnancies and births contributing to maternal morbidity and mortality. This research aims to assess the effectiveness of a free, single-purpose voucher approach in increasing the uptake, use and better targeting of modern contraceptives among women from the lowest two wealth quintiles in rural and urban communities of Punjab province, Pakistan.Methods: A quasi-interventional study with pre- and post-phases was implemented across an intervention (Chakwal) and a control district (Bhakkar) in Punjab province (August 2012-January 2015). To detect a 15% increase in modern contraceptive prevalence rate compared to baseline, 1276 women were enrolled in each arm. Difference-in-Differences (DID) estimates are reported for key variables, and concentration curves and index are described for equity.Results: Compared to baseline, awareness of contraceptives increased by 30 percentage points among population in the intervention area. Vouchers also resulted in a net increase of 16% points in current contraceptive use and 26% points in modern methods use. The underserved population demonstrated better knowledge and utilized the modern methods more than their affluent counterparts. Intervention area also reported a low method-specific discontinuation (13.7%) and high method-specific switching rates (46.6%) amongst modern contraceptive users during the past 24 months. The concentration index indicated that voucher use was more common among the poor and vouchers seem to reduce the inequality in access to modern methods across wealth quintiles.Conclusion: Vouchers can substantially expand contraceptive access and choice among the underserved populations. Vouchers are a good financing tool to improve equity, increase access, and quality of services for the underserved thus contributing towards achieving universal health coverage targets

Penetrating cardiac trauma: A retrospective case series from Karachi.

Penetrating cardiac trauma is a medical emergency that commonly affects young men throughout the world. A retrospective review of the records of all patients presenting with cardiac injury was done from January 2000 to December 2015 at our institute. There were 10 cases of such trauma, all of whom were males, 17 to 48 years of age. The most common mechanism of injury was gunshot wounds followed by stab wounds. The Mean Revised Trauma Score was 7.23±0.855. Only 2 out of the total 10 patients died (20% mortality). The Right Ventricle followed by the Left Ventricle was the most common site of injury. Median Sternotomy was the surgical procedure of choice in managing these patients. Pericardial tamponade and Haemothorax were common intra-operative findings. Patients having penetrating cardiac injury presenting with detectable signs of life on arrival to the hospital can be rescued by early surgical interventio

Association between Injections and HIV Incidence

Editors of medical journals accept that published research should be open to comment and correction in published correspondence ([1]; Box 1).“Post-publication peer review” enables comments on, clarifications of, and corrections to published research. All journals should have a correspondence page for this purpose. I previously criticised the effective “statute of limitations” in several leading general medical journals “whereby authors of papers are immune to disclosure of methodological weaknesses once some arbitrar

Engaging with community-based public and private mid-level providers for promoting the use of modern contraceptive methods in rural Pakistan: Results from two innovative birth spacing interventions

Background: Family planning (FP) interventions aimed at reducing population growth have negligible during the last two decades in Pakistan. Innovative FP interventions that help reduce the growing population burden are the need of the hour. Marie Stopes Society--Pakistan implemented an operational research project--\u27Evidence for Innovating to Save Lives\u27, to explore effective and viable intervention models that can promote healthy timing and spacing of pregnancy in rural and under-served communities of Sindh, Punjab and Khyber Pakhtunkhwa provinces of Pakistan.Methods: We conducted a quasi-experimental (pre- and post-intervention with control arm) study to assess the effectiveness of each of the two intervention models, (1) Suraj model (meaning \u27Sun\u27 in English), which uses social franchises (SF) along with a demand-side financing (DSF) approach using free vouchers, and (2) Community Midwife (CMW) model, in promoting the use of modern contraceptive methods compared to respective controls. Baseline and endline cross-sectional household surveys were conducted, 24 months apart, by recruiting 5566 and 6316 married women of reproductive age (MWRA) respectively. We used Stata version 8 to report the net effect of interventions on outcome indicators using difference-in-differences analysis. Multivariate Cox proportional hazard regression analysis was used to assess the net effect of the intervention on current contraceptive use, keeping time constant and adjusting for other variables in the model.Results: The Suraj model was effective in significantly increasing awareness about FP methods among MWRA by 14% percentage points, current contraceptive use by 5% percentage points and long term modern method--intrauterine device (IUD) use by 6% percentage points. The CMW model significantly increased contraceptive awareness by 28% percentage points, ever use of contraceptives by 7% percentage points and, IUD use by 3% percentage points. Additionally the Suraj intervention led to a 35% greater prevalence (prevalence ratio: 1.35, 95% CI: 1.22-1.50) of contraceptive use among MWRA.Conclusion: Suraj intervention highlights the importance of embedding subsidized FP services within the communities of the beneficiaries. The outcomes of the CMW intervention also improved the use of long-term contraceptives. These findings indicate the necessity of designing and implementing FP initiatives involving local mid-level providers to expand contraceptive coverage in under-served areas

Continuation rates and reasons for discontinuation of intra-uterine device in three provinces of Pakistan: Results of a 24-month prospective client follow-up

Background: Long-acting reversible contraceptives, such as the intrauterine device (IUD), remain underutilised in Pakistan with high discontinuation rates. Based on a 24-month prospective client follow-up (nested within a larger quasi-experimental study), this paper presents the comparison of two intervention models, one using private mid-level providers branded as Suraj and the other using community midwives (CMWs) of Maternal Newborn and Child Health Programme, for method continuation among IUD users. Moreover, determinants of IUD continuation and the reasons for discontinuation, and switching behaviour were studied within each arm.Methods: A total of 1,163 IUD users, 824 from Suraj and 339 from the CMW model, were enrolled in this 24-month prospective client follow-up. Participants were followed-up by female community mobilisers physically every second month to ascertain continued IUD usage and to collect information on associated factors, switching behaviour, reasons for discontinuation, and pregnancy occurrence. The probabilities of IUD continuation and the risk factors for discontinuation were estimated by life table analysis and Cox proportional-hazard techniques, respectively.Results: The cumulative probabilities of IUD continuation at 24 months in Suraj and CMW models were 82% and 80%, respectively. The difference between the two intervention areas was not significant. The probability distributions of IUD continuation were also similar in both interventions (Log rank test: χ(2) = 0.06, df = 1, P = 0.81; Breslow test: χ(2) = 0.6, df = 1, P = 0.44). Health concerns (Suraj = 57.1%, CMW = 38.7%) and pregnancy desire (Suraj = 29.3%, CMW = 40.3%) were reported as the most prominent reasons for IUD discontinuation in both intervention arms. IUD discontinuation was significantly associated with place of residence in Suraj and with age (15-25 years) in the CMW model.Conclusion: CMWs and private providers are equally capable of providing quality IUD services and ensuring higher method continuation. Pakistan\u27s National Maternal Newborn and Child Health programme should consider training CMWs and providing IUDs through them. Moreover, private sector mid-level providers could be engaged in promoting the use of IUDs

Engaging with community-based public and private mid-level providers for promoting the use of modern contraceptive methods in rural Pakistan: results from two innovative birth spacing interventions

Background: Family planning (FP) interventions aimed at reducing population growth have negligible during the last two decades in Pakistan. Innovative FP interventions that help reduce the growing population burden are the need of the hour. Marie Stopes Society - Pakistan implemented an operational research project - ‘Evidence for Innovating to Save Lives’, to explore effective and viable intervention models that can promote healthy timing and spacing of pregnancy in rural and under-served communities of Sindh, Punjab and Khyber Pakhtunkhwa provinces of Pakistan. Methods: We conducted a quasi-experimental (pre - and post-intervention with control arm) study to assess the effectiveness of each of the two intervention models, 1) Suraj model (meaning ‘Sun’ in English), which uses social franchises (SF) along with a demand-side financing (DSF) approach using free vouchers, and 2) Community Midwife (CMW) model, in promoting the use of modern contraceptive methods compared to respective controls. Baseline and endline cross-sectional household surveys were conducted, 24 months apart, by recruiting 5566 and 6316 married women of reproductive age (MWRA) respectively. We used Stata® version 8 to report the net effect of interventions on outcome indicators using difference-in-differences analysis. Multivariate Cox proportional hazard regression analysis was used to assess the net effect of the intervention on current contraceptive use, keeping time constant and adjusting for other variables in the model. Results: The Suraj model was effective in significantly increasing awareness about FP methods among MWRA by 14 % percentage points, current contraceptive use by 5 % percentage points and long term modern method - intrauterine device (IUD) use by 6 % percentage points. The CMW model significantly increased contraceptive awareness by 28 % percentage points, ever use of contraceptives by 7 % percentage points and, IUD use by 3 % percentage points. Additionally the Suraj intervention led to a 35 % greater prevalence (prevalence ratio: 1.35, 95 % CI: 1.22–1.50) of contraceptive use among MWRA. Conclusion: Suraj intervention highlights the importance of embedding subsidized FP services within the communities of the beneficiaries. The outcomes of the CMW intervention also improved the use of long-term contraceptives. These findings indicate the necessity of designing and implementing FP initiatives involving local mid-level providers to expand contraceptive coverage in under-served areas

A study protocol for integrating outpatient services at the primary health care level as part of the universal health coverage benefit package within the national health insurance program of Pakistan through private health facilities

Introduction and aimPakistan has a mixed-health system where up to 60% of health expenditures are out of pocket. Almost 80% of primary healthcare (PHC) facilities are in the private sector, which is deeply embedded within the country’s health system and may account for the unaffordability of healthcare. Since 2016, the existing national health insurance program or Sehat Sahulat Program (SSP), has provided invaluable coverage and financial protection to the millions of low-income families living in Pakistan by providing inpatient services at secondary and tertiary levels. However, a key gap is the non-inclusion of outpatient services at the PHC in the insurance scheme. This study aims to engage a private provider network of general practitioners in select union councils of Islamabad Capital Authority (ICT) of Pakistan to improve access, uptake, and satisfaction and reduce out-of-pocket expenditure on quality outpatient services at the PHC level, including family planning and reproductive health services.Methods and analysisA 24-month research study is proposed with a 12-month intervention period using a mixed method, two-arm, prospective, quasi-experimental controlled before and after design with a sample of 863 beneficiary families from each study arm, i.e., intervention and control groups (N = 1726) will be selected through randomization at the selected beneficiary family/household level from four peri-urban Union Councils of ICT where no public sector PHC-level facility exists. All ethical considerations will be assured, along with quality assurance strategies. Quantitative pre/post surveys and third-party monitoring are proposed to measure the intervention outcomes. Qualitative inquiry with beneficiaries, general practitioners and policymakers will assess their knowledge and practices.Conclusion and knowledge contributionPHC should be the first point of contact for accessing health services and appears to serve as a programmatic engine for universal health coverage (UHC). The research aims to study a service delivery model which harnesses the private sector to deliver an essential package of health services as outpatient services under SSP, ultimately facilitating UHC. Findings will provide a blueprint referral system to reduce unnecessary hospital admissions and improve timely access to healthcare. A robust PHC system can improve population health, lower healthcare expenditure, strengthen the healthcare system, and ultimately make UHC a reality