Distributed convolutional-based coding for cooperative systems

Whenever size, power, or other constraints preclude the use of multiple-input multiple-output (MIMO) systems, wireless systems cannot benefit from the well-known advantages of space-time coding (STC) methods. Also the complexity (multiple radio-frequency (RF) front ends at both the transmitter and the receiver), channel estimation, and spatial correlation in centralized MIMO systems degrade the performance. In situations like these, the alternative would be to resort to cooperative communications via multiple relay nodes. When these nodes work cooperatively, they form a virtual MIMO system. The destination receives multiple versions of the same message from the source and one or more relays, and combines these to create diversity. There are two main cooperative diversity techniques for transmission between a pair of nodes through a multiple relay nodes: decode-and-forward (DF) and amplify-and-forward (AF) modes. In the DF mode, the signal received from the source node is demodulated and decoded before retransmission. In the AF mode, the relay node simply amplifies and retransmits the signal received from the source node. No demodulation or decoding of the received signal is performed in this case. In encoded cooperative communication networks, the diversity of the system degrades significantly. This diversity degradation is attributed to the errors made at the relay nodes. Consequently, if better reliability is achieved at the relay nodes, the diversity may improve. or even may be preserved. as compared to the error-free case. In light of this, the objective of this thesis is to devise coding schemes suitable for relay channels that aim at improving the end-to-end performance of such systems. In this thesis, we present a coding scheme suitable for cooperative networks where the source and relays share their antennas to create a virtual transmit array to transmit towards their destination. We focus on the problem of coding for the relay channels. While the relays may use several forwarding strategies, including AF and DF, we focus on coded DF relaying. We derive upper bounded expressions for the bit error rate (BER) assuming M -ary phase shift keying ( M -PSK) transmission and show that the proposed scheme achieves large coding gains and frill diversity relative to the coded non-cooperative case for a wide range of signal-to-noise ratio (SNR) of interest. To improve the detection reliability further, we consider antenna/relay selection on the performance of cooperative networks in conjunction with the distributed coding scheme proposed. For simplicity, we assume that there is one relay that is equipped with n R antennas and only the best antenna is selected. For this scenario, assuming DF and AF relaying, we derive upper bounds on the BER for M -PSK transmission. Our analytical results show that the proposed scheme achieves full diversity for the entire range of BER of interest, unlike the case without antenna selection. In the last part of the thesis, we consider the same system considered in the ideal case but now with system imperfections. In particular, we consider the case when the channel state information is estimated at all nodes involved in the transmission process. We derive upper bounds on the performance with imperfect channel estimation. Our results show that there is a performance degradation due to the presence of channel estimation error. However, the observations made in the case of ideal channel state information still hold for the non-ideal case

Libya’s Pharmaceutical Situation: A Professional Opinion

Abstract: To improve the countries’ pharmaceutical situation and to monitor the progress, the World Health Organization (WHO) and member states developed a system of indicators to measure the respective important aspects as a prerequisite step. Level I indicators to assess the country’s pharmaceutical situation include the national drug policy; legislation and regulations; drug accessibility and affordability; essential drug list; quality control; pharmacovigilance; storage and distribution; information and rational use. This study is aimed to document the professional opinion of 20 pharmacy practice professionals on Libya’s current pharmaceutical situation, utilizing WHO indicator-based approach. The core indicators measure the most important information needed to understand the pharmaceutical situation in a country. A closed-end questionnaire was distributed to ten practicing pharmacists and ten pharmacy teaching staff members who practice pharmacy. The questionnaires were handed over personally and collected on the same day. The responses were analyzed using simple statistics. The results were argued in the light of the first author’s observation and view, being expert in this field, with reference to the other experts’ views, relevant publications’ findings and WHO reports’ conclusions on these indicators. Suggestions and recommendations for a proper situation assessment, planning and action taking are presented. Primarily, government’s commitment towards appropriate restructuring, management and monitoring of the pharmaceutical sector is crucial. That is to enhance the country’s pharmaceutical situation, to provide and sustain efficient pharmaceutical services and to improve the overall health care system’s performance

A systematic review of outcome and outcome-measure reporting in randomised trials evaluating surgical interventions for anterior-compartment vaginal prolapse: a call to action to develop a core outcome set

INTRODUCTION: We assessed outcome and outcome-measure reporting in randomised controlled trials evaluating surgical interventions for anterior-compartment vaginal prolapse and explored the relationships between outcome reporting quality with journal impact factor, year of publication, and methodological quality. METHODS: We searched the bibliographical databases from inception to October 2017. Two researchers independently selected studies and assessed study characteristics, methodological quality (Jadad criteria; range 1-5), and outcome reporting quality Management of Otitis Media with Effusion in Cleft Palate (MOMENT) criteria; range 1-6], and extracted relevant data. We used a multivariate linear regression to assess associations between outcome reporting quality and other variables. RESULTS: Eighty publications reporting data from 10,924 participants were included. Seventeen different surgical interventions were evaluated. One hundred different outcomes and 112 outcome measures were reported. Outcomes were inconsistently reported across trials; for example, 43 trials reported anatomical treatment success rates (12 outcome measures), 25 trials reported quality of life (15 outcome measures) and eight trials reported postoperative pain (seven outcome measures). Multivariate linear regression demonstrated a relationship between outcome reporting quality with methodological quality (β = 0.412; P = 0.018). No relationship was demonstrated between outcome reporting quality with impact factor (β = 0.078; P = 0.306), year of publication (β = 0.149; P = 0.295), study size (β = 0.008; P = 0.961) and commercial funding (β = -0.013; P = 0.918). CONCLUSIONS: Anterior-compartment vaginal prolapse trials report many different outcomes and outcome measures and often neglect to report important safety outcomes. Developing, disseminating and implementing a core outcome set will help address these issues

Health Education Practice in Libya; Professional Opinions

The aim of this study is to assess the perceptions of Libyan health professionals of their role in the provision of health education to the general public. It is also to identify barriers to effective health education and to suggest actions for a more effective role. A closedend questionnaire was distributed to 500 health professionals in five Libyan localities. Participants were requested to answer questions covering the responsibilities, importance and effectiveness of the existing role of health professionals in health education. Participants were also asked to indicate their perceptions of various barriers to the delivery of effective health education. A list of related suggested solutions for improving the practice was also presented. Nearly two thirds out of 500 health professionals responded to the questionnaire. A large majority perceived that they are responsible for providing health education and almost all (98.9%) considered this role very important or important. The effectiveness of their existing role was assessed differently. Participants perceived that lack of educational aids and materials and low priority for health education were the main barriers that should be overcome in order to improve services

Effect of partial replacing of wheat by sea buckthorn (Hippophae rhamnoides L.) fruit residues in broiler diets on performance and skin pigmentation

Background: Improving poultry products is a constant research topic as the poultry industry aims to provide healthy products to consumers at economic prices and achieve financial profits for breeders. Therefore, recent research has resorted to finding cheap natural sources as alternatives to traditional feed and antibiotics. Aim: The experiment was conducted to study the effects of sea buckthorn fruit residues meal on broilers‘ performance and skin pigmentation. Method: A total of 700 broiler chicks (ROSS 308) were allotted into two groups, and each group comprises 350 birds divided into 10 replicants, 35 birds to each replicant. The experimental group was fed diets where 15% of the wheat was replaced by sea buckthorn residues meal. The control group was fed diets without any color additive. Feed and water were provided ad-libitum. Results: The sea buckthorn fruit residues contained 21% crude protein and metabolisable energy calculated was 9.88 MJ/kg. The live body weight was significantly lower than the experimental group (p < 0.05) on days 14 and 28. The feed conversion ratio was significantly poorer in the experimental group compared with the control group on days 35 of age (p < 0.05). The mortality was higher in the experimental group than in the control group. The DSM Broiler Fan assessed skin color. The skin of the broilers was significantly more yellowish in the experimental group than the control group (103.08 vs. 102.38 scales). The pigmentation of the skin was higher in males than females. Conclusion: The use of sea buckthorn residues in poultry feeding negatively affected the overall performance rate. Mightily, its use in diets depends mainly on the price of feed ingredients. Thus, improving the skin color and biological value of broiler meat can determine its usefulness in broiler feed

Childhood urolithiasis in North-Western Libya

The study reviews causes of urolithiasis and its manifestations in North-West (NW) Libya. Libyan childhood urolithiasis accounted for 3.6% of nephrology out-patient work load. There were 59 children with urolithiasis, including 34 boys and 25 girls with a mean age of 2.8 ± 2.42 years. Urolithiasis was more common among younger age groups (P = 0.001) and in boys with primary oxaluria and infective etiology. The causes of urolithiasis included metabolic stones in 64%, infective in 26%, and it was idiopathic in 10%. Overall, family history of renal stone disease was elicited in 59%; it was 92% in patients with primary oxaluria. The main presenting features were abdominal pain (27%), gross hematuria (22%), associated urinary tract infection (UTI; 24%), and stone release in 19%. Stone location was bilateral in 64%, multiple in 68%, and in the upper tract in 93% (P = 0.05). Important complications encountered included chronic renal failure (13%), hydronephrosis (34%), systemic hypertension (8%), and rickets in 17%. Calcium oxalate was the most prominent constituent, seen in 41% of the calculi, followed by struvite (21%), uric acid (10%), carbapatite (7%), and cystine (3.5%). Diagnostically helpful findings were family history, age at presentation, UTI by urease producing organisms, rickets, imaging and chemical analysis of calculi. Early detection and prompt treatment helps in preventing long-term sequelae in patients with urolithiasis

A systematic review of outcome and outcome-measure reporting in randomised trials evaluating surgical interventions for anterior-compartment vaginal prolapse: a call to action to develop a core outcome set

We assessed outcome and outcome-measure reporting in randomised controlled trials evaluating surgical interventions for anterior-compartment vaginal prolapse and explored the relationships between outcome reporting quality with journal impact factor, year of publication, and methodological quality. We searched the bibliographical databases from inception to October 2017. Two researchers independently selected studies and assessed study characteristics, methodological quality (Jadad criteria; range 1-5), and outcome reporting quality Management of Otitis Media with Effusion in Cleft Palate (MOMENT) criteria; range 1-6], and extracted relevant data. We used a multivariate linear regression to assess associations between outcome reporting quality and other variables. Eighty publications reporting data from 10,924 participants were included. Seventeen different surgical interventions were evaluated. One hundred different outcomes and 112 outcome measures were reported. Outcomes were inconsistently reported across trials; for example, 43 trials reported anatomical treatment success rates (12 outcome measures), 25 trials reported quality of life (15 outcome measures) and eight trials reported postoperative pain (seven outcome measures). Multivariate linear regression demonstrated a relationship between outcome reporting quality with methodological quality (beta = 0.412; P = 0.018). No relationship was demonstrated between outcome reporting quality with impact factor (beta = 0.078; P = 0.306), year of publication (beta = 0.149; P = 0.295), study size (beta = 0.008; P = 0.961) and commercial funding (beta = -0.013; P = 0.918). Anterior-compartment vaginal prolapse trials report many different outcomes and outcome measures and often neglect to report important safety outcomes. Developing, disseminating and implementing a core outcome set will help address these issues

Do we need a core outcome set for childbirth perineal trauma research? A systematic review of outcome reporting in randomised trials evaluating the management of childbirth trauma

BackgroundSelecting appropriate outcomes to reflect both beneficial and harmful effects is a critical step in designing childbirth trauma trials. ObjectiveTo evaluate the outcomes and outcome measures reported in randomised controlled trials evaluating interventions for childbirth trauma. Search strategyRandomised trials were identified by searching bibliographical databases including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and EMBASE. Selection criteriaRandomised trials evaluating the efficacy and safety of different techniques in the management of perineal lacerations. Data collection and analysisTwo researchers independently assessed studies for inclusion, evaluated methodological quality, and extracted the relevant data. Spearman’s correlation and multivariate linear regression analysis using the backward stepwise model were used for analysis. Main resultsForty-eight randomised trials, reporting data from 20 308 women, were included. Seventeen different interventions were evaluated. Included trials reported 77 different outcomes and 50 different outcome measures. Commonly reported outcomes included pain (34 trials; 70%), wound healing (20 trials; 42%), and anorectal dysfunction (16 trials, 33%). In the multivariate analysis, no relationship was demonstrated between the quality of outcome reporting and year of publication (P = 0.31), journal impact factor (P = 0.49), and methodological quality (P = 0.13). ConclusionOutcome reporting in childbirth trauma research is heterogeneous. Developing, disseminating, and implementing a core outcome set in future childbirth trauma research could help address these issues. Tweetable abstractDeveloping @coreoutcomes for childbirth trauma research could help to reduce #research waste. Tweetable abstract Developing @coreoutcomes for childbirth trauma research could help to reduce #research waste. This paper includes Author Insights, a video abstract available a

A systematic review on outcome reporting in randomised controlled trials on surgical interventions for female stress urinary incontinence: a call to develop a core outcome set

BACKGROUND Several meta-analyses have identified methodological limitations in female stress urinary incontinence (SUI) trials, precluding the synthesis of primary studies and high-quality evidence. OBJECTIVES Evaluation of outcome measure selection and outcome reporting in randomised controlled trials (RCTs) on surgery for SUI. SEARCH STRATEGY Systematic review of RCTs identified from bibliographical databases, including Medline, Cochrane, and EMBASE. SELECTION CRITERIA Randomised controlled trials evaluating the efficacy and safety of surgical interventions for the management of female SUI. DATA COLLECTION AND ANALYSIS Two researchers independently assessed the included studies and documented outcomes. MAIN RESULTS Overall, 108 studies were identified that included 422 reported outcomes and 119 outcome measures. The three most common outcomes were cure rates (87 studies), quality of life (85 studies), and overactive bladder (78 studies). The median methodological quality rating was 3 (range 0-3) and the outcome reporting quality rating was 3 (range 0-5). Multinomial logistic regression analysis revealed that the methodological quality and use of validated questionnaire were significant predictors of the quality of outcome reporting (β = 0.538, P < 0.001; β = 0.218, P = 0.011, respectively). CONCLUSIONS Outcome reporting in SUI trials is highly variable. Until a core outcome set is developed and implemented, we propose an interim use of three commonly reported outcomes in each domain (treatment success rate - complete cure, partial improvement, or failure of response; urodynamic evaluation outcomes - overactive bladder (OAB), voiding dysfunction, and urodynamic stress incontinence; patient-reported outcomes - quality of life, sexual dysfunction, and patient satisfaction) with the use of validated questionnaires for patient-reported outcomes and subjective success rates. Complications should be also explicitly and comprehensively reported using validated outcome measures. TWEETABLE ABSTRACT There is significant variation in outcome reporting in SUI trials. Our systematic review findings aim to form the basis for the development of a core outcome set

A systematic review of reported outcomes and outcome measures in randomized trials evaluating surgical interventions for posterior vaginal prolapse to aid development of a core outcome set

Background Recent systematic reviews have demonstrated wide variations on outcome measure selection and outcome reporting in trials on surgical treatments for anterior, apical and mesh prolapse surgery. A systematic review of reported outcomes and outcome measures in posterior compartment vaginal prolapse interventions is highly warranted in the process of developing core outcome sets. Objective To evaluate outcome and outcome measures reporting in posterior prolapse surgical trials. Search strategy We searched MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL). Selection criteria Randomized trials evaluating the efficacy and safety of different surgical interventions for posterior compartment vaginal prolapse. Data collection and analysis Two researchers independently assessed studies for inclusion, evaluated methodological quality, and extracted relevant data. Methodological quality, outcome reporting quality and publication characteristics were evaluated. Main results Twenty-seven interventional and four follow-up trials were included. Seventeen studies enrolled patients with posterior compartment surgery as the sole procedure and 14 with multicompartment procedures. Eighty-three reported outcomes and 45 outcome measures were identified. The most frequently reported outcomes were blood loss (20 studies, 74%), pain (18 studies, 66%) and infection (16 studies, 59%). Conclusions Wide variations in reported outcomes and outcome measures were found. Until a core outcome set is established, we propose an interim core outcome set that could include the three most commonly reported outcomes of the following domains: hospitalization; intraoperative, postoperative urinary, gastrointestinal, vaginal and sexual outcomes; clinical effectiveness. PROSPERO: CRD42017062456