Jointly optimal chunk and power allocation in uplink SC-FDMA

For a single carrier frequency division multiple access (SC-FDMA) system, we obtain the jointly optimal power and chunk allocation policies which maximize the sum rate. Our solution is applicable to both localized and interleaved subcarrier mapping schemes. We solve the joint optimization problem by sequentially solving two sub-problems: power allocation and chunk allocation. Primarily, we use an optimal power allocation algorithm, which we derive from Karush-Kuhn-Tucker (KKT) conditions; and then we convert the optimum chunk assignment problem into a maximum weighted matching problem on a bipartite graph, and hence solve it in polynomial time. We also propose two greedy chunk allocation algorithms with lower complexity, and demonstrate that these algorithms produce near optimal results, especially for interleaved subcarrier mapping, when used in conjunction with optimal power control.Publisher's Versio

The relationship between oxidative stress and coronary artery ectasia

Background: Whereas coronary artery ectasia (CAE) is a rare abnormality of the coronary arteries, co-existent coronary artery disease (CAD) is commonly seen in CAE patients. Since a causative relationship has been shown to exist between oxidative stress and CAD, we sought to determine whether any relationship exists between oxidative stress and CAE. Methods: Fourty four patients with CAE (without CAD) and 86 controls (without any coronary disease) were recruited from among 1,520 patients undergoing coronary angiography. CAE subgroups were determined in accordance with the Markis classification system. Mean values for serum total oxidant status (TOS), total antioxidant status (TAS) and the oxidative stress index (OSI) were statistically compared between these two study groups and among CAE subgroups, with p = 0.05 set as the threshold for statistical significance. Results: TOS and OSI were significantly increased (p = 0.018 and 0.0002) and TAS decreased (p = 0.031) in the CAE versus control group. TOS and TAS were independently related to CAE (p = 0.037 and 0.039), with an r2 of 0.127. Interestingly, however, among CAE subgroups, no differences were observed. Conclusions: Oxidative stress might be implicated in the pathogenesis of CAE. Clinically-defined CAE subgroups did not differ in terms of oxidative stress status. However, the clinical implications of these findings are unclear and warrant further investigation. (Cardiol J 2010; 17, 5: 488-494

LONG-TERM OUTCOMES OF HEMICENTRAL RETINAL VEIN OCCLUSION

Amaç: Hemi-Santral Retinal Ven Tıkanıklığı (HSRVT) tanısıyla izlenen olguların uzun dönem takiplerinde görme sonuçlarını ve komplikasyonları değerlendirmek. Yöntemler: Ocak 1992-Ocak 2001 tarihleri arasında optik koherens tomografi öncesi döneme ait HSRVT tanısı konulan, 2 yıl ve üzeri düzenli takibi olan 25 hastanın 25 gözü retrospektif dosyaları taranarak incelendi. Dosya incelemelerinde hastaların yaşı, cinsiyeti, sistemik risk faktörleri, hangi gözün etkilendiği, tam oftalmolojik muayeneleri ve gelişen komplikasyonlar kaydedildi. İlk başvuda çekilen Fundus Fluoresein Anjiografi (FA) sonuçları incelendi. Hastalar FA bulgularına (noniskemik veya iskemik form) ve üst ya da alt retinal yarı etkilenmesine göre sınıflandırıldı. Bulgular: Hastaların ortalama yaşı 67,0 ± 11,0 yıl (41-90 yıl) ve ortalama takip süresi 6,4 ± 5,5 yıl (2-19 yıl) idi. Olguların 17'sinde (%68) sistemik bir hastalık mevcut olup, en büyük çoğunluğu hipertansiyon hastaları (%48) oluşturmaktaydı. Gözlerin 13'ünde (%52) alt hemisferik kadran ve 12'sinde (%48) üst hemisferik kadranda etkilenme olduğu saptandı. Hastalarımızın tanı esnasında görme keskinliği tüm gözlerde ortalama 1,08 ± 0,4 logMAR iken, son muayenede ortalama 0,89 ± 0,5 logMAR olarak saptandı (p>0,05). FA bulgularına göre tanı esnasında 10 gözde iskemi ve takiplerde noniskemik olguların 3'ünde iskemik forma dönüşüm tespit edildi. On disk alanından daha geniş iskemik alanlara retinal laser fotokoagülasyon uygulandı. HSRVT'ye bağlı 12 gözde makula ödemi, 3 gözde intravitreal hemoraji, 3 gözde epiretinal membran formasyonu, 3 gözde neovasküler glokom, 2 gözde optik atrofi ve 1 gözde yırtıklı retina dekolmanı geliştiği gözlendi. Perfüze makula ödemi tedavisinde grid laser fotokoagülasyon uygulandı. Sonuç: Hastaların uzun dönem takipte görme prognozu, başlangıç görme keskinliği ve komplikasyon gelişimi ile ilişkili bulundu. Hastaların uzun dönem takiplerinde rölatif görme artışı sağlansa bile, bu artış istatistiksel olarak anlamlı bulunmadı Objective: To assess the visual outcomes and the complications in patients with Hemicentral Retinal Vein Occlusion (HCRVO) in the long-term. Methods: The medical records of 25 eyes of 25 patients, having regular follow-up for ≥2 years, diagnosed as HCRVO before Optical Cohorence Tomography (OCT) era between January 1992 and January 2001 were reviewed. During the survey, gender,age, affected side, complete ophthalmologic evaluations, systemic risk factors and complications were recorded. The images of Fundus Fluorescein Angiography (FA) at baseline were evaluated. The patients were classified according to the findings of the FA (non-ischemic or ischemic form) and the involvement of superior or inferior halves of the retina. Results: The mean age of the patients was 67.0 ± 11.0 years (range, 41-90 years) and the mean duration of follow-up was 6.4 ± 5.5 years (range, 2-19 years). Seventeen patients (68%) had a systemic disease and most of them were of hypertensive cases (48%). In 13 of the eyes (52%) inferior hemispheric quadrant and in 12 eyes (48%) superior hemispheric quadrant was found to be affected. The visual acuity at baseline was 1.08 ± 0.4 logMAR and it was 0.89 ± 0.5 logMAR at last visit (p>0.05). According to the findings of FA, ischemic form was detected in 10 eyes at the time of diagnosis, and conversion to ischemic form occured in 3 cases during the follow-up. Laser photocoagulation was performed on ischemic lesions that were more than 10 disc areas. The complications due to HCRVO were as follows; macular edema in 12 eyes, intravitreal hemorrhage in 3 eyes, epiretinal membrane formation in 3 eyes, neovascular glaucoma in 3 eyes, optic atrophy in 2 eyes and regmatogenous retinal detachment in 1 eye. Macular grid laser for perfused macular edema was performed. Conclusion: The visual prognosis of the patients in the long-run was found to be associated with the presenting visual acuity and the development of a complication. Even a relative increase in the visual acuity after the follow-up was achieved, the increase was not statistically significan

Exploring strategies to prevent post-lobectomy space: transient diaphragmatic paralysis using Botulinum Toxin Type A (BTX-A)

OBJECTIVE: Various techniques to reduce air space after pulmonary lobectomy especially for lung cancer have been an important concern in thoracic surgical practice. The aim of this study was to assess the effectiveness of Botulinum toxin A (BTX-A) injection into the diaphragm to reduce air space after right lower pulmonary lobectomy in an animal model. METHODS: Twelve male New Zealand rabbits were randomly allocated into two groups. All animals underwent right lower lobectomy. Then, normal saline of 0,1 ml and 10 units of 0,1 ml Botulinum toxin type A were injected into the muscular part of the right hemidiaphragm in control (n = 6) and BTX-A groups (n = 6) respectively. Residual air space and diaphragmatic elevation were evaluated with chest X-ray pre- and postoperatively. Diaphragmatic elevation was measured as a distance in millimetre from the line connecting the 10th ribs to the midpoint of the right hemidiaphragm. RESULTS: The mean diaphragmatic elevation in BTX-A and control groups were 7.0 ± 2.5 and 1.3 ± 1.2 millimetres respectively. Diaphragmatic elevations were significantly higher in BTX-A group (p = 0.0035). CONCLUSION: Intraoperative Botulinum toxin type A injection may reduce postlobectomy spaces effectively via hemidiaphragmatic paralysis in rabbits. Further studies are needed to validate the safe use of Botulinum toxin type A in human beings

Baseline aortic pre-ejection interval predicts reverse remodeling and clinical improvement after cardiac resynchronization therapy

Background: Cardiac resynchronization therapy (CRT) has been shown to reduce heart failure-related morbidity and mortality. However, approximately one in three patients do not respond to CRT. The aim of the current study was to determine the parameter(s) which predict reverse remodeling and clinical improvement after CRT. Methods: A total of 54 patients (43 male, 11 female; mean age 61.9 ± 10.5 years) with heart failure and New York Heart Association (NYHA) class III–IV symptoms and in whom left ventricular ejection fraction (LVEF) was £ 35% and QRS duration was ≥ 120 ms, despite optimal medical therapy, were enrolled. An echocardiographic examination was performed before, and six months after, CRT. An echocardiographic response was defined as a reduction of end-systolic volume ≥ 10% after six months, and a clinical response was defined as a reduction ≥ 1 in the NYHA functional class score. Results: An echocardiographic response was observed in 38 (70.4%) of the patients and a clinical response occurred in 41 (75.9%) of the patients. Of the dyssynchrony parameters, only the aortic pre-ejection interval (APEI) was observed to significantly predict the clinical response (p = 0.048) and echocardiographic response (p = 0.037). A 180.5 ms cut-off value for the APEI predicted the clinical response with a sensitivity of 92.3% and a specificity of 39%, and the echocardiographic response with a sensitivity of 93.0% and a specificity of 42%. Conclusions: APEI derived from pulsed-wave Doppler, which is available in every echocardiography machine, is a simple and practical method that could be used to select patients for CRT. (Cardiol J 2011; 18, 6: 639–647

Total white blood cell count is associated with the presence, severity and extent of coronary atherosclerosis detected by dual-source multislice computed tomographic coronary angiography

Background: Total white blood cell (WBC) count has been consistently shown to be an independent risk factor and predictor for future cardiovascular outcomes, regardless of disease status in coronary artery disease (CAD). The purpose of this study is to evaluate the relationship between total WBC count and the presence, severity and extent of coronary atherosclerosis detected in subjects undergoing multislice computed tomographic (MSCT) coronary angiography for suspected CAD. Methods: A total of 817 patients were enrolled in this cross-sectional study. Non-significant coronary plaque was defined as lesions causing &#163; 50% luminal narrowing, and significant coronary plaque was defined as lesions causing > 50% luminal narrowing. For each segment, coronary atherosclerotic lesions were categorized as none, calcified, non-calcified and mixed. All images were interpreted immediately after scanning by an experienced radiologist. Results: An association between hypertension, diabetes mellitus, age, gender, hyperlipidemia, smoking, total WBC counts and coronary atherosclerosis was found when patients were grouped into two categories according to the presence of coronary atherosclerosis (p < 0.05). Although plaque morphology was not associated with total WBC counts, the extent of coronary atherosclerosis was increased with higher total WBC quartiles (p = 0.006). Patients with critical luminal stenosis had higher levels of total WBC counts when compared to patients with non-critical luminal narrowing (7,982 &#177; 2,287 vs 7,184 &#177; 1,944, p < 0.05). Conclusions: Our study demonstrated that total WBC counts play an important role in inflammation and are associated with the presence, severity and extent of coronary atherosclerosis detected by MSCT. Further studies are needed to assess the true impact of WBC counts on coronary atherosclerosis, and to promote its use in predicting CAD. (Cardiol J 2011; 18, 4: 371&#8211;377

“The Lolelaplap (Marshall Islands) in Us: Sailing West to East (Ralik→Ratak) to These Our Atolls (Aelon Kein Ad) Ad Jolet Jen Anij (Our Blessed Inheritance from God)”

This paper discusses the expansion of Oceania through a Marshallese indigenous lens as a focal point. It explains that decolonizing methodologies allows reclaiming of space for mental liberation and reassurement of constitutional rights. It highlights similar occurrences of decolonization practices meeting resistance in the 21st century all while strengthening the human right argument that no human deserves any less than their fellow human brothers and sisters. It argues that an indigenous imagery can only be viewed through an indigenous lens where the researches’ level of purity is retained and unfiltered. It nevertheless argues that Marshallese ethnolinguistics reveal the same cultural practices in America, Judeo-Christianity, and Oceania thus dictating the reality that “we are the same not withstanding one stays here and one there (Bedbedjin Bedbedjen, Bedbedjinma wot Kwe)”. It further explains the importance in these similarities and how Marshallese spirituality predates introduced American Judeo-Christianity despite the latter attempting to marginalize the former. It concludes by stating that Marshallese contributions on the global stage are rooted in that culture of love (IaKwe) which is echoed by the custom(s) revealing the significance of Marshallese validation academically, spiritually, economically, & socially to prevent institutionalized discrimination. This paper ends stating that the agency to know one’s self and how one should fit in the world, is a human right in itself and Marshallese are entitled to this sense of self worth through knowing thy self by thy self where real thinking takes place in one’s own mind as we all live our own lives

Plasma osmolality predicts mortality in patients with heart failure with reduced ejection fraction

Background: Heart failure (HF) is a fatal disease. Plasma osmolality with individual impacts of sodium, blood urea nitrogen (BUN), and glucose has not been studied prognostically in patients with HF. Aim: This study aims to investigate the impact of serum osmolality on clinical endpoints in HF patients. Methods: A total of 509 patients (383 males, 126 females) with HF with reduced ejection fraction in three HF centres were retrospectively analysed between January 2007 and December 2013. Follow-up data were completed for 496 patients. Plasma osmolality was calculated as (2 × Na) + (BUN/2.8) + (Glucose/18). Quartiles of plasma osmolality were produced, and the possible relationship between plasma osmolality and cardiovascular mortality was investigated. Results: The mean follow-up was 25 ± 22 months. The mean age was 56.5 ± 17.3 years with a mean EF of 26 ± 8%. The mean levels of plasma osmolality were as follows in the quartiles: 1st % = 280 ± 6, 2nd % = 288 ± 1, 3rd % = 293 ± 2 (95% confidence interval [CI] 292.72–293.3), and 4th % = 301 ± 5 mOsm/kg. The EF and B-type natriuretic peptide levels were similar in the four quartiles. Univariate and multivariate analyses in the Cox proportional hazard model revealed a significantly higher rate of mortality in the patients with hypo-osmolality. The Kaplan-Meier plot showed graded mortality curves with the 1st quartile having the worst prognosis, followed by the 4th quartile and the 2nd quartile, while the 3rd quartile was shown to have the best prognosis. Conclusions: Our study results suggest that normal plasma osmolality is between 275 and 295 mOsm/kg. However, being close to the upper limit of normal range (292–293 mOsm/kg) seems to be the optimal plasma osmolality level in terms of cardiovascular prognosis in patients with HF.Background: Heart failure (HF) is a fatal disease. Plasma osmolality with individual impacts of sodium, blood urea nitrogen (BUN), and glucose has not been studied prognostically in patients with HF. This study aims to investigate the impact of serum osmolality on clinical endpoints in HF patients. Methods: A total of 509 patients (383 males, 126 females) with heart failure with reduced ejection fraction (HFrEF) in three HF centers were retrospectively analyzed between January 2007 and December 2013. Follow up data were completed for 496 patients. Plasma osmolality was calculated as (2*Na)+(BUN/2.8)+(Glucose/18). Quartiles of plasma osmolality were produced and the possible relationship between plasma osmolality and cardiovascular mortality (CV) was investigated.  Results: The mean follow-up was 25±22 months The mean age was 56.5±17.3 years with a mean ejection fraction (EF) of 26±8%. The mean levels of plasma osmolality were as follows in the quartiles: 1st % = 280±6, 2nd % = 288±1, 3rd % = 293±2 (95% confidence interval [CI] 292.72-293.3), 4th % = 301±5 mOsm/kg. The EF and BNP levels were similar in four quartiles. Univariate and multivariate analyses in the Cox proportional hazard model revealed a significantly higher rate of mortality in the patients with hypoosmolality. The Kaplan-Meier plot showed graded mortality curves with the 1st quartile having the worst prognosis, followed by the 4th quartile and the 2nd quartile, while the 3rd quartile was shown to have the best prognosis. Conclusions: Our study results suggest that normal plasma osmolality is between 275 and 295 mOsm/kg. However, being close to the upper limit of normal range (292 to 293 mOsm/kg) seems as the optimal plasma osmolality level in terms of CV prognosis in patients with HF

The Effects of Superficial Musculoaponeurotic System Flap on the Development of Frey’s Syndrome and Cosmetic Outcomes After Superficial Parotidectomy

Objective:To investigate the outcomes of superficial musculoaponeurotic system (SMAS) flap and classic techniques in superficial parotidectomy in terms of Frey’s syndrome (FS) and cosmetic satisfaction.Methods:In this study, a retrospective chart review of patients that underwent superficial parotidectomy was performed. These patients were divided into two subgroups: group 1 included patients in which the SMAS flap was harvested and group 2 comprised the remaining patients on whom classic superficial parotidectomy was performed. All the patients were evaluated clinically and with Minor’s starch-iodine test for FS. For the evaluation of the cosmetic results, the patient’s satisfaction was queried according to the incision scar and surgical field skin retraction/facial symmetry. Both groups were compared in terms of complications and numbness of surgical area.Results:Fifty-five patients (31 male and 24 female) with a mean age of 50.19 years were included in the study. Thirty-two patients were in group 1 and 23 in group 2. Thirteen patients (23.7%) described as having FS and six of them were in group 1, while seven were in group 2. Minor’s starch-iodine test was positive in nine patients in group 1 (28.1%) and six patients in group 2 (26.1%) (p=1.000). With regard to cosmetic satisfaction, eight patients (25%) stated mild discomfort from the incision scar and two patients (6.3%) stated cosmetic dissatisfaction for facial asymmetry in group 1. In group 2 for the same factors the number of patients were 11 (47.8%) and 2 two (8.7%), respectively (p=0.027). There were no statistically significant differences in means of complication and numbness (p>0.05).Conclusion:According to our study results, there was no superiority between both the groups in terms of FS and incision scar satisfaction. We determined that there was a significant benefit of SMAS flap application in the prevention of volume loss and surgical area retraction