Tutorial on LTE/LTE-A Cellular Network Dimensioning Using Iterative Statistical Analysis

LTE is the fastest growing cellular technology and is expected to increase its footprint in the coming years, as well as progress toward LTE-A. The race among operators to deliver the expected quality of experience to their users is tight and demands sophisticated skills in network planning. Radio network dimensioning (RND) is an essential step in the process of network planning and has been used as a fast, but indicative, approximation of radio site count. RND is a prerequisite to the lengthy process of thorough planning. Moreover, results from RND are used by players in the industry to estimate preplanning costs of deploying and running a network; thus, RND is, as well, a key tool in cellular business modelling. In this work, we present a tutorial on radio network dimensioning, focused on LTE/LTE-A, using an iterative approach to find a balanced design that mediates among the three design requirements: coverage, capacity, and quality. This approach uses a statistical link budget analysis methodology, which jointly accounts for small and large scale fading in the channel, as well as loading due to traffic demand, in the interference calculation. A complete RND manual is thus presented, which is of key importance to operators deploying or upgrading LTE/LTE-A networks for two reasons. It is purely analytical, hence it enables fast results, a prime factor in the race undertaken. Moreover, it captures essential variables affecting network dimensions and manages conflicting targets to ensure user quality of experience, another major criterion in the competition. The described approach is compared to the traditional RND using a commercial LTE network planning tool. The outcome further dismisses the traditional RND for LTE due to unjustified increase in number of radio sites and related cost, and motivates further research in developing more effective and novel RND procedures

Absent abdominal muscles, nephro-urologic abnormalities, and severe neurologic damage in an infant with 3 chromosomal duplications: A novel syndrome?

Absent abdominal muscles, cryptorchidism, and hydroureteronephrosis are known to occur in the prune belly syndrome (PBS). We present a male with absent abdominal muscles, severe neurologic damage, with global developmental delay, hydroureteronephrosis, and cryptorchidism. The patient also had arthrogryposis multiplex congenital, low set ears, short neck, micrognathia, bilateral total ptosis, and bilateral clubfeet. Genetic testing (CGH array) revealed 3 novel duplications of unknown clinical significance at 7q11.23, 9q22.32 (PTCH 1 gene), and 12q21.32 (CEP 290 gene).Conclusion: We feel that our patient represents a novel entity, henceforth not described in the literature

Anticoagulation for the long-term treatment of venous thromboembolism in patients with cancer

Background: Cancer increases the risk of thromboembolic events in patients including those receiving anticoagulation treatments. Objectives: To compare the efficacy and safety of low molecular weight heparin (LMWH) and oral anticoagulants for the long-term treatment of venous thromboembolism (VTE) in patients with cancer. Search methods: We conducted a comprehensive search for studies of anticoagulation in cancer patients including 1. a February 2013 electronic search of: the Cochrane Central Register of Controlled Trials (CENTRAL Issue 12, 2012), MEDLINE, and EMBASE; 2. a handsearch of conference proceedings; 3. checking of references of included studies; 4. use of the 'related citation' feature in PubMed; and 5. a search of clinicaltrials.gov for ongoing studies. Selection criteria: We included randomized controlled trials (RCTs) comparing long-term treatment with LMWH versus oral anticoagulants (vitamin K antagonist (VKA) or ximelagatran) in patients with cancer and symptomatic objectively confirmed VTE. Data collection and analysis: Using a standardized data form, we extracted data on methodological quality, participants, interventions and outcomes of interest: survival, recurrent VTE, major bleeding, minor bleeding, thrombocytopenia, and postphlebitic syndrome. We assessed the quality of evidence at the outcome level following the GRADE approach. Main results: Of 9559 identified citations, 10 RCTs (11 reports) were eligible and reported data for 1981 patients with cancer. We excluded 14 studies in which patients with cancer constituted study subgroups, but did not report outcome data for them. Meta-analysis of seven RCTs comparing LMWH with VKA found no statistically significant survival benefit (hazard ratio (HR) 0.96; 95% confidence interval (CI) 0.81 to 1.14) but a statistically significant reduction in VTE (HR 0.47; 95% CI 0.32 to 0.71). The remaining findings did not exclude a beneficial or harmful effect of LMWH compared with VKA for the outcomes of major bleeding (RR 1.07; 95% CI 0.52 to 2.19), minor bleeding (RR 0.89; 95% CI 0.51 to 1.55), or thrombocytopenia (RR 0.98; 95% CI 0.57 to 1.66). We judged the quality of evidence as low for mortality, major bleeding, and minor bleeding, and as moderate for recurrent VTE. One RCT comparing dabigatran with VKA did not exclude beneficial or harmful effects of one agent over the other. One RCT comparing six months' extension of anticoagulation with 18 months of ximelagatran 24 \u3bcg twice daily versus no extended ximelagatran did not exclude beneficial or harmful effects for the outcomes of reduction in VTE, mortality, and minor bleeding. One RCT comparing once-weekly subcutaneous injection of idraparinux for three or six months versus standard treatment (parenteral anticoagulation followed by warfarin or acenocoumarol) suggested a reduction in recurrent VTE (HR 0.39; 95% CI 0.14 to 1.11) at six months, but did not exclude beneficial or harmful effects for the outcomes of mortality (HR 0.99; 95% CI 0.66 to 1.48) and major bleeding (RR 1.04; 95% CI 0.39 to 2.83). Authors' conclusions: For the long-term treatment of VTE in patients with cancer, LMWH compared with VKA reduces venous thromboembolic events but not mortality. The decision for a patient with cancer and VTE to start long-term LMWH versus oral anticoagulation should balance the benefits and harms and integrate the patient's values and preferences for the important outcomes and alternative management strategies

Post-graduation migration intentions of students of Lebanese medical schools: a survey study

<p>Abstract</p> <p>Background</p> <p>The international migration of physicians is a global public health problem. Lebanon is a source country with the highest emigration factor in the Middle East and North Africa and the 7th highest in the World. Given that residency training abroad is a critical step in the migration of physicians, the objective of this study was to survey students of Lebanese medical schools about their intentions to train abroad and their post training plans.</p> <p>Methods</p> <p>Our target population consisted of all students of Lebanese medical schools in the pre-final and final years of medical school. We developed the survey questionnaire based on the results of a qualitative study assessing the intentions and motives for students of Lebanese medical schools to train abroad. The questionnaire inquired about student's demographic and educational characteristics, intention to train abroad, the chosen country of abroad training, and post-training intention of returning to Lebanon.</p> <p>Results</p> <p>Of 576 eligible students, 425 participated (73.8% response rate). 406 (95.5%) respondents intended to travel abroad either for specialty training (330 (77.6%)) or subspecialty training (76 (17.9%)). Intention to train abroad was associated with being single compared with being married. The top 4 destination countries were the US (301(74.1%)), France (49 (12.1%)), the United Kingdom (31 (7.6%)) and Canada (17 (4.2%)). One hundred and two (25.1%) respondents intended to return to Lebanon directly after finishing training abroad; 259 (63.8%) intended to return to Lebanon after working abroad temporarily for a varying number or years; 43 (10.6%) intended to never return to Lebanon. The intention to stay indefinitely abroad was associated male sex and having a 2^ndcitizenship. It was inversely associated with being a student of one of the French affiliated medical schools and a plan to train in a surgical specialty.</p> <p>Conclusion</p> <p>An alarming percentage of students of Lebanese medical schools intend to migrate for post graduate training, mainly to the US. A minority intends to return directly to Lebanon after finishing training abroad.</p

What guidance are researchers given on how to present network meta-analyses to end-users such as policymakers and clinicians? A systematic review

© 2014 Sullivan et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Introduction: Network meta-analyses (NMAs) are complex methodological approaches that may be challenging for non-technical end-users, such as policymakers and clinicians, to understand. Consideration should be given to identifying optimal approaches to presenting NMAs that help clarify analyses. It is unclear what guidance researchers currently have on how to present and tailor NMAs to different end-users. Methods: A systematic review of NMA guidelines was conducted to identify guidance on how to present NMAs. Electronic databases and supplementary sources were searched for NMA guidelines. Presentation format details related to sample formats, target audiences, data sources, analysis methods and results were extracted and frequencies tabulated. Guideline quality was assessed following criteria developed for clinical practice guidelines. Results: Seven guidelines were included. Current guidelines focus on how to conduct NMAs but provide limited guidance to researchers on how to best present analyses to different end-users. None of the guidelines provided reporting templates. Few guidelines provided advice on tailoring presentations to different end-users, such as policymakers. Available guidance on presentation formats focused on evidence networks, characteristics of individual trials, comparisons between direct and indirect estimates and assumptions of heterogeneity and/or inconsistency. Some guidelines also provided examples of figures and tables that could be used to present information. Conclusions: Limited guidance exists for researchers on how best to present NMAs in an accessible format, especially for non-technical end-users such as policymakers and clinicians. NMA guidelines may require further integration with end-users' needs, when NMAs are used to support healthcare policy and practice decisions. Developing presentation formats that enhance understanding and accessibility of NMAs could also enhance the transparency and legitimacy of decisions informed by NMAs.The Canadian Institute of Health Research (CIHR) Drug Safety and Effectiveness Network (Funding reference number – 116573)

Graduates of Lebanese medical schools in the United States: an observational study of international migration of physicians

BACKGROUND: As healthcare systems around the world are facing increasing physician shortages, more physicians are migrating from low to high income countries. As an illustrative case of international migration of physicians, we evaluated the current number and historical trends of Lebanese medical graduates (LMG) in the US, and compared their characteristics to those of US medical graduates (USMG) and other international medical graduates (IMG). METHODS: We evaluated the number of LMG using the 2004 the American Medical Association Physicians' Professional Data (AMA-PPD) and then compared it to the number of graduates of other countries. We evaluated the historical trends using the 1978–2004 historical files of the AMA-PPD. We analyzed the characteristics of all LMG and compared them to a random sample of 1000 USMG and a random sample of 1000 IMG using the 2004 AMA-PPD. RESULTS: In 2004, there were 2,796 LMG in the US, constituting 1.3% of all IMG. Compared to other foreign countries contributing to the US physician workforce, Lebanon ranked 2nd after adjusting for country population size (about 4 million) and 21st overall. About 40% of those who graduated from Lebanese medical schools in the last 25 years are currently active physicians in the US. Since 1978, the number of LMG in the US showed a consistent upward trend at a rate of approximately 71 additional graduates per year. Compared with USMG and IMG, LMG were more likely to work in medical research (OR = 2.31; 95% Confidence Interval (CI) = 1.21; 4.43 and OR = 2.63; 95% CI = 1.34; 5.01, respectively) and to be board certified (OR = 1.43; 95% CI = 1.14; 1.78 and OR = 2.04; 95% CI = 1.65;2.53, respectively) and less likely to be in family practice (OR = 0.14; 95% CI = 0.10; 0.19 and OR = 0.18; 95% CI = 0.12; 0.26, respectively). CONCLUSION: Given the magnitude and historical trends of migration of LMG to the US, further exploration of its causes and impact is warranted. High income countries should consider the consequences of their human resources policies on both low income countries' and their own healthcare systems

The triglyceride glucose-waist-to-height ratio outperforms obesity and other triglyceride-related parameters in detecting prediabetes in normal-weight Qatari adults: A cross-sectional study

IntroductionThe triglyceride-glucose (TyG)-driven indices, incorporating obesity indices, have been proposed as reliable markers of insulin resistance and related comorbidities such as diabetes. This study evaluated the effectiveness of these indices in detecting prediabetes in normal-weight individuals from a Middle Eastern population.MethodsUsing the data of 5,996 adult Qatari participants from the Qatar Biobank cohort, we employed adjusted logistic regression to assess the ability of various obesity and triglyceride-related indices to detect prediabetes in normal-weight (18.5 ≤ BMI &lt;25 kg/m2) adults (≥18 years).ResultsOf the normal-weight adults, 13.62% had prediabetes. TyG-waist-to-height ratio (TyG-WHTR) was significantly associated with prediabetes among normal-weight men [OR per 1-SD 2.68; 95% CI (1.67–4.32)] and women [OR per 1-SD 2.82; 95% CI (1.61–4.94)]. Compared with other indices, TyG-WHTR had the highest area under the curve (AUC) value for prediabetes in men [AUC: 0.76, 95% CI (0.70–0.81)] and women [AUC: 0.73, 95% CI (0.66–0.80)], and performed significantly higher than other indices (p &lt; 0.05) in detecting prediabetes in men. Tyg-WHTR shared similar diagnostic values as fasting plasma glucose (FPG).DiscussionOur findings suggest that the TyG-WHTR index could be a better indicator of prediabetes for general clinical usage in normal weight Qatari adult men than other obesity and TyG-related indices. TyG-WHTR can help identify a person’s risk for developing prediabetes in both men and women when combined with FPG results

Wireless Monitoring of Liver Hemodynamics In Vivo

Abstract Liver transplants have their highest technical failure rate in the first two weeks following surgery. Currently, there are limited devices for continuous, real-time monitoring of the graft. In this work, a three wavelengths system is presented that combines near-infrared spectroscopy and photoplethysmography with a processing method that can uniquely measure and separate the venous and arterial oxygen contributions. This strategy allows for the quantification of tissue oxygen consumption used to study hepatic metabolic activity and to relate it to tissue stress. The sensor is battery operated and communicates wirelessly with a data acquisition computer which provides the possibility of implantation provided sufficient miniaturization. In two in vivo porcine studies, the sensor tracked perfusion changes in hepatic tissue during vascular occlusions with a root mean square error (RMSE) of 0.135 mL/min/g of tissue. We show the possibility of using the pulsatile wave to measure the arterial oxygen saturation similar to pulse oximetry. The signal is also used to extract the venous oxygen saturation from the direct current (DC) levels. Arterial and venous oxygen saturation changes were measured with an RMSE of 2.19% and 1.39% respectively when no vascular occlusions were induced. This error increased to 2.82% and 3.83% when vascular occlusions were induced during hypoxia. These errors are similar to the resolution of a commercial oximetry catheter used as a reference. This work is the first realization of a wireless optical sensor for continuous monitoring of hepatic hemodynamics

Paraneoplastic thrombocytosis in ovarian cancer

&lt;p&gt;Background: The mechanisms of paraneoplastic thrombocytosis in ovarian cancer and the role that platelets play in abetting cancer growth are unclear.&lt;/p&gt; &lt;p&gt;Methods: We analyzed clinical data on 619 patients with epithelial ovarian cancer to test associations between platelet counts and disease outcome. Human samples and mouse models of epithelial ovarian cancer were used to explore the underlying mechanisms of paraneoplastic thrombocytosis. The effects of platelets on tumor growth and angiogenesis were ascertained.&lt;/p&gt; &lt;p&gt;Results: Thrombocytosis was significantly associated with advanced disease and shortened survival. Plasma levels of thrombopoietin and interleukin-6 were significantly elevated in patients who had thrombocytosis as compared with those who did not. In mouse models, increased hepatic thrombopoietin synthesis in response to tumor-derived interleukin-6 was an underlying mechanism of paraneoplastic thrombocytosis. Tumorderived interleukin-6 and hepatic thrombopoietin were also linked to thrombocytosis in patients. Silencing thrombopoietin and interleukin-6 abrogated thrombocytosis in tumor-bearing mice. Anti–interleukin-6 antibody treatment significantly reduced platelet counts in tumor-bearing mice and in patients with epithelial ovarian cancer. In addition, neutralizing interleukin-6 significantly enhanced the therapeutic efficacy of paclitaxel in mouse models of epithelial ovarian cancer. The use of an antiplatelet antibody to halve platelet counts in tumor-bearing mice significantly reduced tumor growth and angiogenesis.&lt;/p&gt; &lt;p&gt;Conclusions: These findings support the existence of a paracrine circuit wherein increased production of thrombopoietic cytokines in tumor and host tissue leads to paraneoplastic thrombocytosis, which fuels tumor growth. We speculate that countering paraneoplastic thrombocytosis either directly or indirectly by targeting these cytokines may have therapeutic potential. &lt;/p&gt