TOPOLOGY, ANALYSIS, AND CMOS IMPLEMENTATION OF SWITCHED-CAPACITOR DC-DC CONVERTERS

This review highlights various design and realization aspects of three commonly used charge pump topologies, namely, the linear, exponential, and the Fibonacci type of charge pumps. We shall outline the new methods developed recently for analyzing the steady and dynamic performances of these circuits. Some practical issues for the CMOS implementation of these charge pump structures will be critically discussed. Finally, some conventional voltage regulation methods for maintaining a stable output under a large range of loading current and supply voltage fluctuations will be proposed

A Prospective Study of Venous Thromboembolic Prophylaxis Using Foot Pumps Following Total Knee Replacement in a Chinese Population

AbstractPurposeThe purpose of this study was to evaluate foot pumps as mechanical prophylaxis for deep vein thrombosis (DVT) following total knee replacement (TKR) in a Chinese population.MethodsAll consecutive patients following TKR during 2002–2006 received routine duplex ultrasound surveillance for DVT 9 days postoperatively. The demographic data and risk factors were recorded. No medication was given for DVT prophylaxis in all patients.ResultsWe evaluated 91 consecutive TKRs in 85 patients. Although 44 knee replacements (Group 1) done before December 2004 were not given foot pumps, 47 knee replacements (Group 2) done afterwards were given foot pumps. All patients were followed up for more than 6 months. DVT was detected in three cases (6.8%) in Group 1 compared with four knees (8.5%) in Group 2. Proximal thrombosis was observed in two knees (4.5%) in Group 1 compared with two knees (4.3%) in Group 2. No patient had pulmonary embolism. Six out of 59 (10.2%) patients who underwent the operations under general anaesthesia suffered from DVT, whereas one in 28 (3.6%) patients operated under spinal anaesthesia had DVT. All had no statistical significance.ConclusionThe rate of proximal DVT after TKR was low (4.5%) without pharmacological prophylaxis. We advise against the use of pharmacological prophylaxis in Chinese population for TKRs because of the low risk of proximal DVT and its possible bleeding complications. Foot pump did not lower the rate of DVTfurther, and its use for DVT prophylaxis in TKR is not necessary

Association between screen viewing duration and sleep duration, Sleep quality, And excessive daytime sleepiness among adolescents in Hong Kong

© 2014 by the authors; licensee MDPI, Basel, Switzerland. Screen viewing is considered to have adverse impacts on the sleep of adolescents. Although there has been a considerable amount of research on the association between screen viewing and sleep, most studies have focused on specific types of screen viewing devices such as televisions and computers. The present study investigated the duration w ith which currently prevalent screen viewing devices (including televisions, personal computers, mobile phones, and portable video devices) are viewed in relation to sleep duration, sleep quality, and daytime sleepiness among Hong Kong adolescents (N = 762). Television and computer viewing remain prevalent, but were not correlated with sleep variables. Mobile phone viewing was correlated with all sleep variables, while portable video device viewing was shown to be correlated only with daytime sleepiness. The results demonstrated a trend of increase in the prevalence and types of screen viewing and their effects on the sleep patterns of adolescents.Link_to_subscribed_fulltex

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Pharmacist-Managed Refill Service Impacts on Clinician Workload and Medication Interventions in a Federally Qualified Health Center

IntroductionIncreasing administrative workload is linked with lower quality of patient care and physician burnout. Conversely, models involving pharmacists can positively impact patient care and physician well-being. Research has consistently demonstrated that pharmacist-physician collaboration can improve outcomes for chronic diagnoses. Pharmacist-managed refill services may improve provider workload measures and clinical outcomes.MethodsThis was an evaluation of a pharmacist-managed refill service at a Federally Qualified Health Center (FQHC). Under collaborative practice agreement, pharmacists addressed refill requests and recommended interventions. Data analysis evaluated effectiveness of the model, including clinical interventions, and involved descriptive statistics and qualitative approaches.ResultsAverage patient age was 55.5 years old and 53.1% were female. Turnaround time was within 48 h for 87.8% of refill encounters. During an average of 3.2 h per week, pharmacists addressed 9.2% (n = 1683 individual requests in 1255 indirect patient encounters) of the total clinic refill requests during the 1-year study period. In 453 of these encounters (36.1%), pharmacists recommended a total of 642 interventions. 64.8% of these were need for appointment (n = 211) or labs (n = 205). Drug therapy problems and medication list discrepancies were identified in 12.6% (n = 81) and 11.9% (n = 76) of encounters, respectively.Discussion and conclusionsThe results of this study are consistent with previous literature demonstrating the value of interprofessional collaboration. Pharmacists addressed refills in an efficient, clinically effective manner in an FQHC setting. This may positively impact primary care provider workload, patients' medication persistence, and clinical care

Pharmacist-Managed Refill Service Impacts on Clinician Workload and Medication Interventions in a Federally Qualified Health Center

Introduction: Increasing administrative workload is linked with lower quality of patient care and physician burnout. Conversely, models involving pharmacists can positively impact patient care and physician well-being. Research has consistently demonstrated that pharmacist-physician collaboration can improve outcomes for chronic diagnoses. Pharmacist-managed refill services may improve provider workload measures and clinical outcomes. Methods: This was an evaluation of a pharmacist-managed refill service at a Federally Qualified Health Center (FQHC). Under collaborative practice agreement, pharmacists addressed refill requests and recommended interventions. Data analysis evaluated effectiveness of the model, including clinical interventions, and involved descriptive statistics and qualitative approaches. Results: Average patient age was 55.5 years old and 53.1% were female. Turnaround time was within 48 h for 87.8% of refill encounters. During an average of 3.2 h per week, pharmacists addressed 9.2% (n = 1683 individual requests in 1255 indirect patient encounters) of the total clinic refill requests during the 1-year study period. In 453 of these encounters (36.1%), pharmacists recommended a total of 642 interventions. 64.8% of these were need for appointment (n = 211) or labs (n = 205). Drug therapy problems and medication list discrepancies were identified in 12.6% (n = 81) and 11.9% (n = 76) of encounters, respectively. Discussion and Conclusions: The results of this study are consistent with previous literature demonstrating the value of interprofessional collaboration. Pharmacists addressed refills in an efficient, clinically effective manner in an FQHC setting. This may positively impact primary care provider workload, patients’ medication persistence, and clinical care

Radiomics from Various Tumour Volume Sizes for Prognosis Prediction of Head and Neck Squamous Cell Carcinoma: A Voted Ensemble Machine Learning Approach

Background: Traditionally, cancer prognosis was determined by tumours size, lymph node spread and presence of metastasis (TNM staging). Radiomics of tumour volume has recently been used for prognosis prediction. In the present study, we evaluated the effect of various sizes of tumour volume. A voted ensemble approach with a combination of multiple machine learning algorithms is proposed for prognosis prediction for head and neck squamous cell carcinoma (HNSCC). Methods: A total of 215 HNSCC CT image sets with radiotherapy structure sets were acquired from The Cancer Imaging Archive (TCIA). Six tumour volumes, including gross tumour volume (GTV), diminished GTV, extended GTV, planning target volume (PTV), diminished PTV and extended PTV were delineated. The extracted radiomics features were analysed by decision tree, random forest, extreme boost, support vector machine and generalized linear algorithms. A voted ensemble machine learning (VEML) model that optimizes the above algorithms was used. The receiver operating characteristic area under the curve (ROC-AUC) were used to compare the performance of machine learning methods, including accuracy, sensitivity and specificity. Results: The VEML model demonstrated good prognosis prediction ability for all sizes of tumour volumes with reference to GTV and PTV with high accuracy of up to 88.3%, sensitivity of up to 79.9% and specificity of up to 96.6%. There was no significant difference between the various target volumes for the prognostic prediction of HNSCC patients (chi-square test, p > 0.05). Conclusions: Our study demonstrates that the proposed VEML model can accurately predict the prognosis of HNSCC patients using radiomics features from various tumour volumes