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Uromodulin is a kidney-specific glycoprotein which is exclusively produced by the epithelial cells lining the thick ascending limb and early distal convoluted tubule. It is currently recognized as a multifaceted player in kidney physiology and disease, with discrete roles for intracellular, urinary, interstitial and serum uromodulin. Among these, uromodulin modulates renal sodium handling through the regulation of tubular sodium transporters that reabsorb sodium and are targeted by diuretics, such as the loop diuretic–sensitive Na+-K+-2Cl− cotransporter type 2 (NKCC2) and the thiazide-sensitive Na+/Cl− cotransporter (NCC). Given these roles, the contribution of uromodulin to sodium-sensitive hypertension has been proposed. However, recent studies in humans suggest a more complex interaction between dietary sodium intake, uromodulin and blood pressure. This review presents an updated overview of the uromodulin's biology and its various roles, and focuses on the interaction between uromodulin and sodium-sensitive hypertension. [ABSTRACT FROM AUTHOR]

The change in heating and cooling needs of Greece in the near future due to the climate change is assessed in the present study. Global and regional climate models and two different representative concentration pathways (RCPs) are used to simulate the expected change in temperature. A widely used methodology of computation of heating degree days (HDDs) and cooling degree days (CDDs) is employed with a base temperature of 18 °C. In agreement with the expected temperature rise in the near future, an HDD decrease and CDD increase under both RCPs is also expected. The changes under RCP8.5 are stronger compared to those under RCP4.5. Differences related to topography are noted. The HDD decrease is stronger than CDD increase but the relative increase in CDDs is higher than the relative increase in HDDs. The highest absolute decreases in HDDs are expected for February and March while the highest absolute increases in CDDs are expected during the three summer months. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that was first identified in December 2019 and emerged into an ongoing global pandemic. Both the pandemic itself and the associated public restrictive measures of social mobility established with different intensity over different periods in various countries have significantly affected the everyday activities and lifestyles of people all over the world. The impact of lockdown and quarantine measures on hypertension incidence and blood pressure (BP) control is an important topic that requires further investigation. The aim of this review is: a) to present the current evidence regarding the actual effects of public restrictive measures on BP levels and control, originating primarily from studies investigating the impact of public restrictive measures on BP control with the use of various BP phenotypes; b) to summarize the possible pandemic-related effects of factors known to affect BP levels, including both traditional (e.g. dietary habits including alcohol and sodium intake, body weight, smoking and physical activity) and non-traditional (e.g. sleep patterns, air pollution, environmental noise, delayed diagnosis and medication adherence) ones. [ABSTRACT FROM AUTHOR]

Objectives Micro–computed tomography (micro-CT) is a novel, nondestructive, slide-free digital imaging modality that enables the acquisition of high-resolution, volumetric images of intact surgical tissue specimens. The aim of this systematic mapping review is to provide a comprehensive overview of the available literature on clinical applications of micro-CT tissue imaging and to assess its relevance and readiness for pathology practice. Methods A computerized literature search was performed in the PubMed, Scopus, Web of Science, and CENTRAL databases. To gain insight into regulatory and financial considerations for performing and examining micro-CT imaging procedures in a clinical setting, additional searches were performed in medical device databases. Results Our search identified 141 scientific articles published between 2000 and 2021 that described clinical applications of micro-CT tissue imaging. The number of relevant publications is progressively increasing, with the specialties of pulmonology, cardiology, otolaryngology, and oncology being most commonly concerned. The included studies were mostly performed in pathology departments. Current micro-CT devices have already been cleared for clinical use, and a Current Procedural Terminology (CPT) code exists for reimbursement of micro-CT imaging procedures. Conclusions Micro-CT tissue imaging enables accurate volumetric measurements and evaluations of entire surgical specimens at microscopic resolution across a wide range of clinical applications. [ABSTRACT FROM AUTHOR]

Atherosclerotic renovascular disease (ARVD) represents the most common type of renal artery stenosis. In the last decade, a few large trials failed to demonstrate the superiority of standard medical therapy plus percutaneous transluminal renal angioplasty (PTRA) compared with medical therapy alone in lowering blood pressure levels or preventing adverse renal and cardiovascular outcomes in patients with ARVD. However, this issue remains controversial and an ongoing debate focusses on the benefits that selected patients could experience from renal revascularization procedures. In this regard, several pieces of observational data show that PTRA is associated with future cardiorenal benefits in patients presenting with high-risk ARVD phenotypes. Such evidence resulted in a progressive shift in relevant recommendations, with most recent not-graded suggestions supporting that revascularization should be offered in these high-risk subjects. Existing evidence clearly calls for a properly designed randomized controlled trial with selected patients presenting high-risk ARVD phenotypes, in order to confirm the superiority of PTRA versus non-invasive management in this patient group and objectively guide everyday clinical practice. [ABSTRACT FROM AUTHOR]

Background: Immunotherapy of gastrointestinal cancers is challenging; however, several lines of evidence suggest that adoptive transfer of stimulated or modified immune cells support not only protective role of immune cells in tumor microenvironment, but actively participate in the elimination of cancer cells.Methods: In vivo studies employing cancer cell-derived allograft murine models of gastrointestinal cancers were performed. The effects of T helper (Th) 2 cells on gastrointestinal cancers growth and tumor microenvironment composition using adoptive transfer of Th2 cells, interleukin (IL)-5 treatment, and immunofluorescence, multiplex and real-time PCR were explored.Results: Here, we show that Th2 cells play an essential role in the inhibition of colon and pancreas cancers progression. In murine models of gastrointestinal tumors using adoptive transfer of Th2 cells, we identify that Th2 cells are responsible for generation of apoptotic factors and affect macrophage as well as eosinophil recruitment into tumors where they produce cytotoxic factors. Moreover, we found that Th2 cells lead to IL-5 hypersecretion, which links the anti-tumorigenic function of Th2 cells and eosinophils. Importantly, we noted that recombinant IL-5 administration is also related with inhibition of gastrointestinal tumor growth. Finally, using an in vitro approach, we documented that both Th2 cells and eosinophils are directly responsible for gastrointestinal cancer cell killing.Conclusions: These data demonstrate the significance of Th2 cells, eosinophils and IL-5 in the inhibition of gastrointestinal tumor growth, and pointed toward tumor microenvironment reprogramming as a Th2 cell-mediated anti-tumorigenic mechanism of action. [ABSTRACT FROM AUTHOR]

Background: Increased arterial stiffness is suggested to be involved in the pathogenesis of intradialytic‐hypertension (IDH). Ambulatory pulse‐wave‐velocity (PWV) is an independent predictor for all‐cause‐mortality in haemodialysis and its prognostic power is better than office PWV. This is the first study examining ambulatory central blood pressure (BP) and arterial stiffness parameters in patients with and without IDH. Methods: This study examined 45 patients with IDH (SBP rise ≥10 mmHg from pre‐ to post‐dialysis and post‐dialysis SBP ≥150 mmHg) in comparison with 197 patients without IDH. All participants underwent 48‐h ABPM with Mobil‐O‐Graph‐NG; parameters of central haemodynamics, wave reflection and PWV were estimated. Results: Age, dialysis vintage and interdialytic weight gain did not differ between‐groups. IDH patients had higher 48‐h cSBP (131.7 ± 16.2 vs. 119.2 ± 15.2 mmHg, p < 0.001), 48‐h cDBP (86.7 ± 12.7 vs. 79.6 ± 11.5 mmHg, p < 0.001) and 48‐h cPP (45.5 ± 10.4 vs. 39.8 ± 10.0 mmHg, p = 0.001) compared to patients without IDH. Similarly, during day‐ and nighttime periods, cSBP/cDBP and cPP levels were higher in IDH‐patients compared to non‐IDH. Forty‐eight‐hour augmentation pressure and index, but not AIx(75) were higher in IDH patients; 48‐h PWV (10.0 ± 2.0 vs. 9.2 ± 2.1 m/s, p = 0.017) was significantly higher in patients with IDH. The two study groups displayed different trajectories in central BP and PWV over the course of the recording; IDH patients had steadily high values of the above variables during the 2 days of the interdialytic‐interval, whereas non‐IDH patients showed a gradual elevation, with significant increases from the 1st to 2nd 24 h. Conclusions: IDH patients have significantly higher levels of ambulatory central BP and arterial stiffness parameters and a different course over the 48‐h period compared with non‐IDH patients. Increased arterial stiffness could be a prominent factor associated with the high burden of cardiovascular disease in this population. [ABSTRACT FROM AUTHOR]

Background: Diabetes mellitus (DM) and coronary artery disease (CAD) constitute inter-related clinical entities. Biomarker profiling emerges as a promising tool for the early diagnosis and risk stratification of either DM or CAD. However, studies assessing the predictive capacity of novel metabolomics biomarkers in coexistent CAD and DM are scarce. Methods: This post-hoc analysis of the CorLipid trial (NCT04580173) included 316 patients with CAD and comorbid DM who underwent emergency or elective coronary angiography due to acute or chronic coronary syndrome. Cox regression analyses were performed to identify metabolomic predictors of the primary outcome, which was defined as the composite of major adverse cardiovascular or cerebrovascular events (MACCE: cardiovascular death, myocardial infarction, stroke, major bleeding), repeat unplanned revascularizations and cardiovascular hospitalizations. Linear regression analyses were also performed to detect significant predictors of CAD complexity, as assessed by the SYNTAX score. Results: After a median 2-year follow up period (IQR = 0.7 years), the primary outcome occurred in 69 (21.8%) of patients. Acylcarnitine ratio C4/C18:2, apolipoprotein (apo) B, history of heart failure (HF), age > 65 years and presence of acute coronary syndrome were independent predictors of the primary outcome in diabetic patients with CAD (aHR = 1.89 [1.09, 3.29]; 1.02 [1.01, 1.04]; 1.28 [1.01, 1.41]; 1.04 [1.01, 1.05]; and 1.12 [1.05–1.21], respectively). Higher levels of ceramide ratio C24:1/C24:0, acylcarnitine ratio C4/C18:2, age > 65 and peripheral artery disease were independent predictors of higher CAD complexity (adjusted β = 7.36 [5.74, 20.47]; 3.02 [0.09 to 6.06]; 3.02 [0.09, 6.06], respectively), while higher levels of apoA1 were independent predictors of lower complexity (adjusted β= − 0.65 [− 1.31, − 0.02]). Conclusions: In patients with comorbid DM and CAD, novel metabolomic biomarkers and metabolomics-based prediction models could be recruited to predict clinical outcomes and assess the complexity of CAD, thereby enabling the integration of personalized medicine into routine clinical practice. These associations should be interpreted taking into account the observational nature of this study, and thus, larger trials are needed to confirm its results and validate them in different and larger diabetic populations. [ABSTRACT FROM AUTHOR]

Background: The role of non-invasive ventilation (NIV) in severe COVID-19 remains a matter of debate. Therefore, the utilization and outcome of NIV in COVID-19 in an unbiased cohort was determined. Aim: The aim was to provide a detailed account of hospitalized COVID-19 patients requiring non-invasive ventilation during their hospital stay. Furthermore, differences of patients treated with NIV between the first and second wave are explored. Methods: Confirmed COVID-19 cases of claims data of the Local Health Care Funds with non-invasive and/or invasive mechanical ventilation (MV) in the spring and autumn pandemic period in 2020 were comparable analysed. Results: Nationwide cohort of 17.023 cases (median/IQR age 71/61–80 years, 64% male) 7235 (42.5%) patients primarily received IMV without NIV, 4469 (26.3%) patients received NIV without subsequent intubation, and 3472 (20.4%) patients had NIV failure (NIV-F), defined by subsequent endotracheal intubation. The proportion of patients who received invasive MV decreased from 75% to 37% during the second period. Accordingly, the proportion of patients with NIV exclusively increased from 9% to 30%, and those failing NIV increased from 9% to 23%. Median length of hospital stay decreased from 26 to 21 days, and duration of MV decreased from 11.9 to 7.3 days. The NIV failure rate decreased from 49% to 43%. Overall mortality increased from 51% versus 54%. Mortality was 44% with NIV-only, 54% with IMV and 66% with NIV-F with mortality rates steadily increasing from 62% in early NIV-F (day 1) to 72% in late NIV-F (>4 days). Conclusions: Utilization of NIV rapidly increased during the autumn period, which was associated with a reduced duration of MV, but not with overall mortality. High NIV-F rates are associated with increased mortality, particularly in late NIV-F. [ABSTRACT FROM AUTHOR]

Granulocyte colony-stimulating factor (G-CSF) is produced at high levels in several cancers and is directly linked with metastasis in gastrointestinal (GI) cancers. In order to further understand the alteration of molecular compositions and biochemical features triggered by G-CSF treatment at molecular and cell levels, we sought to investigate the long term treatment of G-CSF on colon and breast cancer cells measured by label-free, non-invasive single-cell Raman microspectroscopy. Raman spectrum captures the molecule-specific spectral signatures ("fingerprints") of different biomolecules presented on cells. In this work, mouse breast cancer line 4T1 and mouse colon cancer line CT26 were treated with G-CSF for 7 weeks and subsequently analyzed by machine learning based Raman spectroscopy and gene/cytokine expression. The principal component analysis (PCA) identified the Raman bands that most significantly changed between the control and G-CSF treated cells. Notably, here we proposed the concept of aggressiveness score, which can be derived from the posterior probability of linear discriminant analysis (LDA), for quantitative spectral analysis of tumorigenic cells. The aggressiveness score was effectively applied to analyze and differentiate the overall cell biochemical changes of G-CSF-treated two model cancer cells. All these tumorigenic progressions suggested by Raman analysis were confirmed by pro-tumorigenic cytokine and gene analysis. A high correlation between gene expression data and Raman spectra highlights that the machine learning based non-invasive Raman spectroscopy offers emerging and powerful tools to better understand the regulation mechanism of cytokines in the tumor microenvironment that could lead to the discovery of new targets for cancer therapy. [ABSTRACT FROM AUTHOR]

Pectus Excavatum (PE) or "funnel chest," the most common deformity of the anterior chest wall characterized by sternal depression, can be repaired via either operative or non-invasive techniques. Vacuum Bell (VB) device is the most widespread of the latter one which can be applied either intraoperatively or as monotherapy. The present narrative review examines the efficacy of that innovative method. A thorough search of the literature resulted in 13 English-written articles concerning VB therapy from its first description to February 2019. The studies included patients with mild to moderate PE, mainly evaluated via Haller-Index and/or sternum depth prior to and following treatment. Concerning depth-improvement, 37-90% showed amelioration while 10-40% of them an excellent correction to normal. In 42%, Haller-Index also improved with a median decrease of 0.3 after VB application. A correlation was attempted to be found between the efficacy of VB and factors such as the frequency and duration of VB application, patient age, gender, PE severity and type, and differential pressure of the suction cup. Complications may be frequent yet mild and temporary. Intraoperatively, VB widows Minimally Invasive Repair of Pectus Excavatum (MIRPE) operation a safer procedure with greater results. VB as conservative treatment is an effective and well-tolerated alternative therapeutic option for selected patients with PE who meet specific criteria. It also constitutes a device of significant efficacy, appropriate for intraoperative use during MIRPE procedure. [ABSTRACT FROM AUTHOR]

Background: In the last five decades a continuous increase in the average global temperature has been recorded. Furthermore, natural disasters (e.g. heat waves, severe storms, floods and large forest fires) are becoming more frequent. The impact of global warming and climate change on health involves an increase in respiratory, cardiovascular, renal and cognitive mental diseases. Furthermore, a change in the frequency and patterns of infectious diseases can also be observed in Europe.Material and Methods: This article presents the most important studies that investigated diseases associated with the climate change, with special reference to those that represent a challenge for intensive care medicine.Results: Currently available epidemiological data and statistical extrapolations indicate that diseases resulting from the climate change (acute infection-related respiratory and intestinal diseases, exacerbation of pre-existing pulmonary lesions, heat-related dehydration, cerebral insults and myocardial infarction) are relevant for intensive care medicine. Particular emphasis is placed on a significant increase in acute kidney damage during heat waves. A previously unknown pattern of infectious diseases necessitates new knowledge and targeted management. In some studies, persisting mental impairments were registered during heat waves and natural disasters, e.g. posttraumatic stress disorder.Conclusion: Intensive care medicine must be prepared for the challenges due to global warming and climate change. Slow but continuous changes (e.g. rise in temperature) as well as acute changes (e.g. heat waves and natural disasters) will induce an increased need for intensive medical care services (e.g. an increase in the need for renal replacement procedures). Intensive care physicians will need to be familiar with the diagnostics and management of diseases associated with the climate change. An initiative of the specialist societies involved would be welcomed. [ABSTRACT FROM AUTHOR]

We report new nanocomposites with poly(benzoxazine-co-epoxy) matrix reinforced with 1 wt% graphene. Curabox 24-111, a benzoxazine resin was copolymerised with Epilok 60-566, a mixture of epoxy resins. Copolymerisation was also carried out in the presence of different graphene powders, namely, Nanene-001 and Nanene-002, used as single fillers and as mixture (relative weight ratio 70:30 or 30:70). DSC results showed the addition of either single filler caused a delay in polymerisation and an increase in the exothermic peak temperature of the curing reaction with a related reduction in ΔH Total. compared to the neat copolymer. Copolymerisation showed a 38% reduction and 24% increase in tensile modulus (E) compared to the neat polybenzoxazine and epoxy polymer, with a respective 18% and 30% reduction in tensile strength (TS). Nanocomposites with 0.7wt% Nanene-002 + 0.3 wt% Nanene-001 showed the highest increase of 35% in TS, a 1.6% reduction in E and 36% increase in elongation at break (EB) compared to the neat copolymer matrix. Samples with 1 wt% Nanene-001 showed the largest reduction of 21% in E, a 27% increase in TS and a 45% increase in EB. Additionally, TGA thermographs showed a 22°C increase in the onset of degradation (300°C–322°C) improving the materials thermal stability. [ABSTRACT FROM AUTHOR]

Abstract The Price-Rind 92 parameterization (Price and Rind, 1992) that utilizes cloud top height as predictor for the estimation of lightning density is widely used by modelers in an attempt to forecast electrical activity in thunderstorms. In the present paper new parameterizations for the estimation of lightning density of convective clouds are formulated. LINET lightning data, NWC SAF (Satellite Application Facility on support to Nowcasting and Very Short-Range Forecasting) products and ERA-Interim (ECMWF-Re Analysis) data, covering the summer of 2016 over continental Europe, are used. The proposed models estimate the lightning density of convective clouds, using cloud top height, cloud top pressure and cold cloud depth as predictors. Model efficiency statistics calculated over an independent dataset, suggest that the proposed models can be considered successful over the specific area (continental Europe) and period (summer). The new cloud top height model differs from the PR92 and other parameterizations, which is not an unexpected result, since every model has its own characteristics, strengths and weaknesses. The new parameterizations could be utilized in numerical model simulations to produce quantitative estimations of the amount of strokes over convective areas. Highlights • LINET VLF/LF lightning data, NWC SAF products, and ERA-interim data are used. • The cloud top height/pressure and cold cloud depth relationship to lightning during summer over central Europe is examined. • Uncertainties of the observational data are considered in the modeling process using the Generalized Least Squares technique. • The cross-validation of these models against the control dataset yield low RMSE values, suggesting successful fits. [ABSTRACT FROM AUTHOR]

In the last five decades, human activities have resulted in the release of increasing quantities of carbon dioxide and other greenhouse gases, thus contributing to global climate change by additional heating of the atmosphere. In consequence, in future, the European intensivist - who already should be aware of uncommon vector-borne diseases due to global tourism - must be further sensitized to presently uncommon or tropical mosquito-borne diseases such as malaria and dengue, or other vector-borne viral, fungal, or bacterial transmissions like coccidioidomycosis or avian influenza. It seems that a rise in mortality, emergency room visits, and (intensive care) hospitalization due to cardiopulmonary diseases attendant on heat stress, extreme weather conditions, or air pollution are more certain than worst-case horror scenarios. It has been shown that acute and intensive care services vary substantially across economic regions, in high-income as well as in low-income countries [[17]], and it is debatable whether the current structure of intensive care is yet armed for needs related to climate change. [Extracted from the article]

The history of critical care is littered with examples of the "cost" of trying to normalize abnormal physiology during critical illness in the attempt to improve outcomes - supranormal oxygen delivery, liberal red cell transfusion, ventilation to normal blood gas parameters, and intensive glycemic control [[1]]. Extracorporeal membrane oxygenation (ECMO) is a complex, costly, and resource-intensive intervention for patients with severe cardiac and/or pulmonary failure. Finally, the highest mortality rates for patients supported with ECMO (or who are critically ill in general) are those who are more than 75 years and/or are frail, making these important factors when considering whether to offer ECMO to these patients. Critical care costs account for nearly 1% of GDP in the United States [[13]], and ECMO is a good example of a high-cost intervention delivered in the ICU. [Extracted from the article]

Background: Veno-venous extracorporeal CO removal (vv-ECCOR) is increasingly being used in the setting of acute respiratory failure. Blood flow rates through the device range from 200 ml/min to more than 1500 ml/min, and the membrane surface areas range from 0.35 to 1.3 m. The present study in an animal model with similar CO production as an adult patient was aimed at determining the optimal membrane lung surface area and technical requirements for successful vv-ECCOR. Methods: Four different membrane lungs, with varying lung surface areas of 0.4, 0.8, 1.0, and 1.3m were used to perform vv-ECCOR in seven anesthetized, mechanically ventilated, pigs with experimentally induced severe respiratory acidosis (pH 7.0-7.1) using a 20Fr double-lumen catheter with a sweep gas flow rate of 8 L/min. During each experiment, the blood flow was increased stepwise from 250 to 1000 ml/min. Results: Amelioration of severe respiratory acidosis was only feasible when blood flow rates from 750 to 1000 ml/min were used with a membrane lung surface area of at least 0.8 m. Maximal CO elimination was 150.8 ml/min, with pH increasing from 7.01 to 7.30 (blood flow 1000 ml/min; membrane lung 1.3 m). The membrane lung with a surface of 0.4 m allowed a maximum CO elimination rate of 71.7 mL/min, which did not result in the normalization of pH, even with a blood flow rate of 1000 ml/min. Also of note, an increase of the surface area above 1.0 m did not result in substantially higher CO elimination rates. The pressure drop across the oxygenator was considerably lower (<10 mmHg) in the largest membrane lung, whereas the smallest revealed a pressure drop of more than 50 mmHg with 1000 ml blood flow/min. Conclusions: In this porcine model, vv-ECCOR was most effective when using blood flow rates ranging between 750 and 1000 ml/min, with a membrane lung surface of at least 0.8 m. In contrast, low blood flow rates (250-500 ml/min) were not sufficient to completely correct severe respiratory acidosis, irrespective of the surface area of the membrane lung being used. The converse was also true, low surface membrane lungs (0.4 m) were not capable of completely correcting severe respiratory acidosis across the range of blood flows used in this study. [ABSTRACT FROM AUTHOR]

Background: The most widely used graft as a replacement in anterior cruciate ligament (ACL) reconstruction is the semitendinosus (ST) tendon graft. After harvesting for ACL reconstruction, the hamstring tendon regenerates in most people and becomes similar to normal. The effect of graft harvest on muscle morphology and function remains unclear. The present study aimed to examine the morphology of the ST during isometric contraction after harvesting the ST tendon for ACL reconstruction. Methods: Maximal isometric contractions of the knee flexors from two angular positions were performed by 8 participants, at least 1 year after ACL reconstruction with an ST tendon graft and 8 matched controls. Ultrasonographic images were used to measure the pennation angle and muscle thickness of the ST muscle. Results: There was not a statistically significant difference in pennation angle values between the control group and the group who underwent ACL reconstruction (p >0.05). Muscle thickness was significantly higher in the ACLR group compared with controls (p< 0.05). Conclusions: Individuals who underwent ACL reconstruction display a higher ST muscle thickness but similar pennation angle compared with controls. This indicates that ACL reconstruction has an effect on ST muscle belly but effect on force generation capacity is rather limited. Level of evidence: IIb. [ABSTRACT FROM AUTHOR]

Many universities have implemented tuition differentials for certain undergraduate degree programs, citing higher degree costs or higher demand. However, most college accounting systems are unsuited for measuring cost differentials by degree program. This research outlines a method that can convert commonly available financial data to a more appropriate form for cost analysis. Results show that the average faculty teaching salary cost differs between degree programs, but that these differences are more a function of class size and success rates than average faculty salaries. [ABSTRACT FROM AUTHOR]

In fifth-generation (5G) wireless networks, heterogeneous networks (HetNets) are used to improve capacity and users' densification. However, to rapidly deploy a large number of femto base stations (BSs) in a cost-efficient manner, they should be connected to the core network through residential broadband links. As such, different femto BSs may have different backhaul capacities, which should be taken into consideration when macro BSs offload traffic to femto BSs. Furthermore, users offloaded to femto BSs can be severely interfered by the macro BSs if macro and femto BSs transmit at the same time in the downlink. This interference can be avoided by proper transmission time scheduling. In view of the problem, this paper proposes a novel scheme to jointly perform traffic offloading and time fraction allocation (TOTFA) to ensure proportional fairness in throughput among the users. The proposed scheme, called TOTFA maximizes the weighted sum of the logarithm of user throughput, subject to constraints imposed by the backhaul capacity. Simulation results show that TOTFA can improve aggregated throughput up to 100% compared with a baseline scheme when the backhaul link capacity is 1.25 Mb/s. Over a range of different backhaul capacities, the average throughput improvement is 45%. [ABSTRACT FROM PUBLISHER]

Cooperative diversity systems with optimal and suboptimal antenna and relay selection have been paid significant attention for more than half a decade. However, optimal antenna and relay selection strategies require global channel state information (CSI), which is a cumbersome process. In this paper, we propose a diversity-optimal and three suboptimal transmit–receive antenna and relay selection strategies, named S1, S2, and S3, for decode-and-forward cooperative relaying systems, equipped with Nt and Nr antennas at the source (S) and the destination (D), respectively, and considering a multirelay scenario. Furthermore, we study the symbol error probability (SEP) for these strategies, assuming M-ary phase-shift keying signaling over Rayleigh fading channels. In addition, we perform diversity order analysis through closed-form asymptotic SEP expressions. Since the proposed suboptimal strategies, i.e., S2 and S3, involve the so-called switch-and-examine combining scheme, we compare the complexity of S1, S2, and S3 in terms of the average number of CSI required at D to select the best transmit–receive antenna pair and relay. From the derived SEP expressions, it can be concluded that all three suboptimal strategies achieve the same diversity order of N_{t}N_{r}+N, where N$ is the number of relays, except for the case when the switching threshold signal-to-noise ratio (SNR) is much lower than the average SNR in S2 and S3. Finally, the diversity-optimal strategy achieves full diversity order of N_{t}N_{r}+N\min(N_{t},N_{r}). [ABSTRACT FROM AUTHOR]

An analysis of selected spatiotemporal characteristics of isolated thunderstorms in relation to cloud-to-ground (CG) lightning over part of the eastern Mediterranean is performed. The purpose of the study is twofold: to better understand and improve the basic knowledge of the physical mechanisms of the phenomenon and to offer new means of nowcasting the lightning activity in such thunderstorms. Meteosat Second Generation (MSG) Rapid Scan Service (RSS) infrared imagery which offers the option of tracking the examined storms with a time frequency of 5 minutes is one of the two utilized datasets, the other being ZEUS very low frequency (VLF) lightning detection system’s CG discharge data. It was shown that a cloud top temperature of about −20°C is required for the onset of lightning activity. A rapid drop of the cloud-top temperature of about 11°C in 5 minutes on average is observed a few minutes before or during lightning initiation. The maximization of the activity is usually quite close to the overall minimum cloud-top temperature of the cell. A temperature increase of 3.5°C from this overall minimum can mark the end of the activity, which is also associated to the time evolution of the cell’s horizontal extent. In fact, after the cell’s horizontal area stops to increase and/or starts to gradually diminish, CG lightning activity is expected to stop. [ABSTRACT FROM PUBLISHER]

Purpose: The evolution of the epidemiology and mortality of extracorporeal membrane oxygenation (ECMO) remains unclear. The present study investigates the evolving epidemiology and mortality of various ECMO techniques in Germany over time, used for both severe respiratory and cardiac failure.Methods: Data on all patients receiving venovenous (vv-ECMO) and venoarterial (va-ECMO) ECMO as well as pumpless extracorporeal lung assist/interventional lung assist (PECLA/ILA) outside the operating room in Germany from 1 January 2007 through 31 December 2014 were obtained from the Federal Statistical Office of Germany and analyzed.Results: The incidence of vv-ECMO and va-ECMO in the population increased threefold from 1.0:100,000 inhabitants/year in 2007 to a maximum of 3.0:100,000 in 2012, and from 0.1:100,000 in 2007 to 0.7:100,000 in 2012 and to a maximum of 3.5:100,000 in 2014, respectively. The incidence of arteriovenous PECLA/ILA also increased from 0.4:100,000 to a maximum of 0.6:100,000 in 2011, but decreased thereafter to 0.3:100,000 in 2014. The relative proportion of older patients receiving ECMO is steadily increasing. In-hospital mortality decreased over time and reached 58 and 66 % for vv-ECMO and va-ECMO in 2014, respectively. In addition, mortality steadily increased with age and was especially high in the first 48 h of ECMO use.Conclusions: In a high-income country like Germany, the use of ECMO has been rapidly increasing since 2007 for both respiratory and cardiac support, with a recent plateau in vv-ECMO use. In-hospital mortality decreased with increasing ECMO utilization, but remains high, especially in older patients and in the first 48 h of use. [ABSTRACT FROM AUTHOR]

The development and efficiency assessment of a lightning activity nowcasting tool is presented. The tool employs MSG IR imagery and real-time lightning data provided by ZEUS network to nowcast the manifestation of lightning activity over the Greek mainland for a time span of 1 h. The efficiency of the tool is assessed for 20 days with widespread lightning activity observed during the warm period of the year through a verification procedure that computes a collection of appropriate statistics for selected areas. The analysis of these statistics shows that the tool estimates successfully almost 80% of the upcoming activity. The false alarm rate is close to 40%, while a small overestimation is evident. Since the adverse effects of a case of missed activity are much more than that of a false alarm, the tool is considered successful and fit for operational use. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the moment-arm and cross-sectional area (CSA) of the patellar tendon (PT) and the hamstrings after anterior cruciate ligament (ACL) reconstruction. The right knee of five males who underwent ACL reconstruction with a PT graft and five age-matched controls was scanned using magnetic resonance image scans. Based on three-dimensional (3D) solids of the PT, CSAs and moment-arms of semitendinous (ST), biceps femoris (BF) long head and semimembranosus (SM) were estimated. Analysis of variance indicated no significant group differences in muscle moment-arms (p>0.05). 3D moment-arms of PT, ST and BF were significantly lower than the corresponding 2D values (p < 0.05). The ACL group displayed a significantly higher maximum BF CSA, a lower ST CSA (p < 0.05) but similar PT and SM CSAs compared with controls. It is concluded that any alterations in PT properties 1 year after harvesting do not affect knee muscle moment-arms compared with age-matched controls. Moment-arm estimation differed between 3D and 2D data, although it did not affect comparisons between ACL reconstruction group and controls. Design of rehabilitation programmes should take into consideration a potential alteration in hamstring morphology following surgery with a PT graft. [ABSTRACT FROM AUTHOR]

The study investigated the role of motivation and metacognition in the formation of cognitive and affective outcomes from participation in physical education lessons within the framework of self-determination theory. A sample of 630 adolescents (M age = 14.06, SD = .29) participated in the study. Participants completed questionnaires including measures of perceived autonomy support in PE, autonomous motivation in PE, metacognitive processes in PE, enjoyment, boredom in PE and intention for leisure-time physical activity. Multiple linear regression analyses revealed that perceptions of autonomy supportive motivational climate significantly predicted enjoyment, boredom and intentions towards leisure-time physical activity. In addition autonomous motivation and metacognition significantly predicted enjoyment, boredom and intentions, whereas controlling motivation was a significant predictor of boredom. Multiple mediation modeling indicated that perceptions of autonomy supporting climate on these responses was mediated mainly by autonomous motivation and metacognition. The findings of the present study provide valuable information on the mediating role of autonomous motivation and metacognition on the effects of autonomy supportive motivational climate on students' cognitive and affective responses during physical education lessons. [ABSTRACT FROM AUTHOR]

Simple, highly fluorinated receptors are shown to function as highly effective transmembrane anion antiporters with the most active transporters rivalling the transport efficacy of natural anion transporter prodigiosin for bicarbonate. [ABSTRACT FROM AUTHOR]

This study presents a methodology for modeling and mapping the seasonal and annual air temperature and precipitation climate normals over Greece using several topographical and geographical parameters. Data series of air temperature and precipitation from 84 weather stations distributed evenly over Greece are used along with a set of topographical and geographical parameters extracted with Geographic Information System methods from a digital elevation model (DEM). Normalized difference vegetation index (NDVI) obtained from MODIS Aqua satellite data is also used as a geographical parameter. First, the relation of the two climate elements to the topographical and geographical parameters was investigated based on the Pearson's correlation coefficient to identify the parameters that mostly affect the spatial variability of air temperature and precipitation over Greece. Then a backward stepwise multiple regression was applied to add topographical and geographical parameters as independent variables into a regression equation and develop linear estimation models for both climate parameters. These models are subjected to residual correction using different local interpolation methods, in an attempt to refine the estimated values. The validity of these models is checked through cross-validation error statistics against an independent test subset of station data. The topographical and geographical parameters used as independent variables in the multiple regression models are mostly those found to be strongly correlated with both climatic variables. Models perform best for annual and spring temperatures and effectively for winter and autumn temperatures. Summer temperature spatial variability is rather poorly simulated by the multiple regression model. On the contrary, best performance is obtained for summer and autumn precipitation while the multiple regression model is not able to simulate effectively the spatial distribution of spring precipitation. Results revealed also a relatively weaker model performance for precipitation than that for air temperature probably due to the highly variable nature of precipitation compared to the relatively low spatial variability of air temperature field. The correction of the developed regression models using residuals improved though not significantly the interpolation accuracy. [ABSTRACT FROM AUTHOR]

Visual sensing of the environment is crucial for flying an unmanned aerial vehicle (UAV) and is a centerpiece of many related applications. The ability to run computer vision and machine learning algorithms onboard an unmanned aerial system (UAS) is becoming more of a necessity in an effort to alleviate the communication burden of high-resolution video streaming, to provide flying aids, such as obstacle avoidance and automated landing, and to create autonomous machines. Thus, there is a growing interest on the part of many researchers in developing and validating solutions that are suitable for deployment on a UAV system by following the general trend of edge processing and airborne computing, which transforms UAVs from moving sensors into intelligent nodes that are capable of local processing. In this paper, we present, in a rigorous way, the design and implementation of a 12.85 kg UAV system equipped with the necessary computational power and sensors to serve as a testbed for image processing and machine learning applications, explain the rationale behind our decisions, highlight selected implementation details, and showcase the usefulness of our system by providing an example of how a sample computer vision application can be deployed on our platform. [ABSTRACT FROM AUTHOR]

This work studies the effects of graphene nanoplatelets (GNPs) and hexagonal boron nitride (hBN) on the thermal and mechanical properties of polydimethylsiloxane (PDMS) matrix for use as thermal interface materials (TIMs). Solution mixing of 10 wt% GNPs and 40 wt% hBN with PDMS produced TIMs with through-plane thermal conductivity (TC) of 1.24 W m−1 K−1 showing a 519% increase relative to the neat matrix. A synergistic effect between GNPs and hBN was particularly demonstrated when in samples with 48 wt% total filler content, 8 wt% hBN was replaced by GNPs, and the TC was increased by 33%. The elongation at break of the hBN (40 wt%)/GNP (8 wt%) samples reached 151%, representing a 160% increase when compared to samples with only 40 wt% hBN. Moreover, the shore hardness of samples containing 40 wt% hBN was 68 A, and the introduction of 8 wt% GNPs caused a decrease to 38 A. DSC measurements on samples filled with hBN and GNPs showed a reduction up to 65% in Ultimate Heat of Curing, which was attributed to the presence of graphene flakes interfering with the curing of the matrix. Graphene was found to be an efficient filler in tuning the thermal and mechanical properties of TIMs. [ABSTRACT FROM AUTHOR]

Abstract: We compare the performance of a typical hole transport layer for organic photovoltaics (OPVs), Poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) thin film with a series of PEDOT:PSS layers doped with silver (Ag) nanoparticles (NPs) of various size distributions. These hybrid layers have attracted great attention as buffer layers in plasmonic OPVs, although there is no report up to date on their isolated performance. In the present study we prepared a series of PEDOT:PSS layers sandwiched between indium tin oxide (ITO) and gold (Au) electrodes. Ag NPs were deposited on top of the ITO by electron beam evaporation followed by spin coating of PEDOT:PSS. Electrical characterization performed in the dark showed linear resistive behavior for all the samples; lower resistance was observed for the hybrid ones. It was found that the resistivity of the samples decreases with increasing the particle's size. A substantial increase of the electric field between the ITO and the Au electrodes was seen through the formation of current paths through the Ag NPs. A striking observation is the slight increase in the slope of the current density versus voltage curves when measured under illumination for the case of the plasmonic layers, indicating that changes in the electric field in the vicinity of the NP due to plasmonic excitation is a non-vanishing factor. [Copyright &y& Elsevier]

Highlights: [•] Introduction of a metric for estimating dissimilarities among items’ attributes. [•] Introduction of a recommender which bases its rating estimations on dissimilarities. [•] A framework which combines recommenders with the dissimilarity recommender. [ABSTRACT FROM AUTHOR]

Bis(thio)urea receptors (1–4) based on 1,2-bisaminocyclohexane are shown to function as transmembrane anion antiporters. The results show thatcis-receptors have a greater propensity for anion transport than analogoustrans-receptors. Stability constants using1H NMR techniques highlight the significance of stereoisomerism on anion binding in solution, ascis-receptors bind anions more strongly thantrans-receptors. [ABSTRACT FROM AUTHOR]

Abstract: Background: An exciting direction in nanomedicine would be to analyze how living cells respond to conducting polymers. Their application for tissue regeneration may advance the performance of drug eluting stents by addressing the delayed stent re-endothelialization and late stent thrombosis. Methods: The suitability of poly (3, 4-ethylenedioxythiophene) (PEDOT) thin films for stents to promote cell adhesion and proliferation is tested in correlation with doping and physicochemical properties. PEDOT doped either with poly (styrenesulfonate) (PSS) or tosylate anion (TOS) was used for films' fabrication by spin coating and vapor phase polymerization respectively. PEGylation of PEDOT: TOS for reduced immunogenicity and biofunctionalization of PEDOT: PSS with RGD peptides for induced cell proliferation was further applied. Atomic Force Microscopy and Spectroscopic Ellipsometry were implemented for nanotopographical, structural, optical and conductivity measurements in parallel with wettability and protein adsorption studies. Direct and extract testing of cell viability and proliferation of L929 fibroblasts on PEDOT samples by MTT assay in line with SEM studies follow. Results: All PEDOT thin films are cytocompatible and promote human serum albumin adsorption. PEDOT:TOS films were found superior regarding cell adhesion as compared to controls. Their nanotopography and hydrophilicity are significant factors that influence cytocompatibility. PEGylation of PEDOT:TOS increases their conductivity and hydrophilicity with similar results on cell viability with bare PEDOT:TOS. The biofunctionalized PEDOT:PSS thin films show enhanced cell proliferation. Conclusions: The application of PEDOT polymers has evolved as a new perspective to advance stents. General significance: In this work, nanomedicine involving nanotools and novel nanomaterials merges with bioelectronics to stimulate tissue regeneration for cardiovascular implants. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. [Copyright &y& Elsevier]

Abstract: Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is one of the most promising conducting polymers that can be used as transparent electrode or as buffer layer for organic electronic devices. However, when used as an electrode, its conductivity has to be optimized either by the addition of solvents or by post-deposition processing. In this work, we investigate the effect of the addition of the polar solvent dimethylsulfoxide (DMSO) to an aqueous PEDOT:PSS solution on its optical and electrical properties by the implementation of the Drude model for the analysis of the measured pseudo-dielectric function by Spectroscopic Ellipsometry from the near infrared to the visible–far ultraviolet spectral range. The results show that the addition of DMSO increases significantly the film conductivity, which reaches a maximum value at an optimum DMSO concentration as it has confirmed by experimentally measured conductivity values. The post-deposition thermal annealing has been found to have a smaller effect on the film conductivity. [Copyright &y& Elsevier]

Abstract: The primary goal of managing MSW incineration residues is to avoid any impact on human health or the environment. Incineration residues consist of bottom ash, which is generally considered as rather harmless and fly ash which usually contains compounds which are potentially harmful for public health. Small quantities of ash (both bottom and fly) are produced currently in Greece, mainly from the healthcare waste incineration facility in Attica region. Once incineration plants for MSW (currently under planning) are constructed in Greece, the produced ash quantities will increase highly. Thus, it is necessary to organize, already at this stage, a roadmap towards disposal/recovery methods of these ash quantities expected. Certain methods, related to the treatment of the future generated ash which are more appropriate to be implemented in Greece are highlighted in the present paper. The performed analysis offers a waste management approach, having 2016 as a reference year for two different incineration rates; 30% and 100% of the remaining MSW after recycling process. The results focus on the two greater regions of Greece: Attica and Central Macedonia. The quantity of potential future ash generation ranges from 137 to 459kt for Attica region and from 62 to 207kt for central Macedonia region depending on the incineration rate applied. Three alternative scenarios for the treatment of each kind of ash are compiled and analysed. Metal recovery and reuse as an aggregate in concrete construction proved to be the most advantageous -in terms of economy-bottom ash management scenario. Concerning management of the fly ash, chemical treatment with phosphoric solution addition results to be the lowest total treatment cost and is considered as the most profitable solution. The proposed methodology constitutes a safe calculation model for operators of MSW incineration plants regardless of the region or country they are located in. [Copyright &y& Elsevier]

Absract: In the present work we compare the performance of organic solar cells, based on the bulk heterojunction system of P3HT:PCBM when adequate silver nanoparticles (NPs) are incorporated in two distinct places among the device structure. Introduction of NPs on top of the transparent anode revealed better overall performance with an increased efficiency of 17%. Alternatively, placing the NPs on top of the active photovoltaic layer resulted to 25% higher photo-current generation albeit with inferior electrical characteristics (i.e series and shunt resistance). Our findings suggest that enhanced scattering to non-specular directions from NPs site is maximized when penetrating light meets the particles after the polymer blend, but even this mechanism is not sufficient enough to explain the enhanced short circuit current observed. A second mechanism should be feasible; that is plasmon enhancement which is more efficient in the case where NPs are in direct contact with the polymer blend. J–V characteristics measured in the dark showed that NPs placed on top of the ITO film act as enhanced hole conducting sites, as evident by the lower series resistance values in these cells, suggesting this mechanism as more significant in this case. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article related to Tourette Syndrome (TS) in the November 15, 2011 issue.

Abstract: A non-stoichiometric model for a downdraft gasifier was developed in order to simulate the overall gasification process. Mass and energy balances of the gasifier were calculated and the composition of produced syngas was predicted. The capacity of the modeled gasifier was assumed to be 0.5MW, with an Equivalence Ratio (EQ) of 0.45. The model incorporates the chemical reactions and species involved, while it starts by selecting all species containing C, H, and O, or any other dominant elements. Olive wood, miscanthus and cardoon were tested in the formulated model for a temperature range of 800–1200°C, in order to examine the syngas composition and the moisture impact on the supplied fuel. Model results were then used in order to design an olive wood gasification reactor. [Copyright &y& Elsevier]

A novel analytical framework for evaluating the statistics of the product of independent random variables is proposed. Compared with other methods, which use either infinite series or special functions, the new method provides simple and efficient closed-form approximations, in terms of elementary functions, such as powers and exponentials. Numerical results, which are used to check the accuracy of the new approximations, show that it is quite accurate in most regions of interest. As an application, the proposed analytical results can be efficiently used in wireless communications theory to evaluate in closed form the outage probability of cascaded fading channels, as well as the rate offset of the hybrid automatic repeat request (H-ARQ) transmission. Numerical examples show that the derived expressions provide significant insights on the behaviors of important system parameters as the outage probability and the rate offset. [ABSTRACT FROM PUBLISHER]

Climatic aspects of extreme European precipitation are studied. Daily pluviometric data from 280 stations across Europe, covering the period from 1958 to 2000, are used. First, the criteria for extreme precipitation cases and episodes are communicated using threshold and spatial definitions. The cases and episodes meeting these criteria are grouped according to their area of appearance. Most of them are located in three major areas: Greece, the Alps, and the Iberian Peninsula. The existence of trends in the annual and seasonal time series of these extreme events is examined. Decreasing trends are found in most of the cases, for Greece, the Iberian Peninsula, and Europe, as a whole. The Alps present a different behavior, with no trend at all in the southern part, and a possible increasing trend in the northern part. Finally, the positive impact of altitude in the frequency of occurrence of extreme precipitation episodes in Europe is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Gasification of biomass, municipal solid waste, waste-derived fuels and residues has been lately gaining in attractiveness as an alternative thermal treatment method to produce power and heat. Presented in this paper is a new, recently patented, 3-stage gasification scheme, designed for all aforementioned types of fuels and for producing a synthesis gas free of tar and dioxins. The proposed 3-stage gasification scheme comprises of three stages: i) pyrolysis, ii) combustion and iii) gasification. The proposed 3-stage gasification scheme is valid for municipal solid waste and any type of biomass despite differences in chemical composition. The innovation of this 3-stage gasification scheme is based on the fact that the transition between normal and reverse operation and vice versa is achieved only by the proper rotation settings of four air blowers, thus creating a new model of gaseous flow management between the three aforementioned stages. The presented model can achieve a safe industrial-scale operation while producing a gas free of harmful components. The proposed gasification model is validated as suitable for small-to-medium scale capacities, achieving an overall electrical efficiency of 30% and minimum environmental impacts well below all existing thresholds, including those set by the Directive 2000/76/EC on solid waste incineration. [Copyright &y& Elsevier]

The coordination chemistry of 2,5-dicarbothioamidopyrrole ligands, namely N2,N5-dibutyl-3,4-diphenyl-1H-pyrrole-2,5-bis(carbothioamide) and N2,N5,3,4-tetraphenyl-1H-pyrrole-2,5-bis(carbothioamide), has been investigated with Cu(ii) metal centres by means of X-ray crystallography. This resulted in the formation of the expected planar S,N,S′ coordinated complex for the former ligand and unexpected ring-closure reactions, with formation of benzothiazole sidearms, for the latter. Both Cu(ii) and Cu(i), used in large excess, were found to favour the ring-closure reaction, although the structural characterisation of the resulting complexes contained only Cu(ii) cations, with varying coordination geometries ranging from square planar and square-based pyramidal to tetrahedral. By repeating the reaction using a slight excess of Cu(ii) (2 : 1) two more different structures were obtained where the metal was coordinated to the original ligand, N2,N5,3,4-tetraphenyl-1H-pyrrole-2,5-bis(carbothioamide), or to the mixed ligand where only one of the thioamide substituents had converted to a benzothiazole. The essential role of Cu for the ring closure reaction was also established by comparing its complex with structural features of the analogous Co(ii) complex, the latter revealing no ring closure to give benzothiazole substituents and co-crystallisation of a mixed Co(ii)/Co(iii) complex. Finally, the structure and photophysical properties of the corresponding 3,4-diphenyl-2,5-bis(benzothiozol-5-yl)-pyrrole ligand, obtained viatreatment of the thioamide with K3[Fe(CN)6], were also investigated revealing a blue-centered emission. [ABSTRACT FROM AUTHOR]

Abstract: The achievement of the desirable morphology at the nanometer scale of bulk heterojunctions consisting of a conjugated polymer with fullerene derivatives is a prerequisite in order to optimize the power conversion efficiency of organic solar cells. The various experimental conditions such as the choice of solvent, drying rates and annealing have been found to significantly affect the blend morphology and the final performance of the photovoltaic device. In this work, we focus on the effects of post deposition thermal annealing at 140°C on the blend morphology, the optical and structural properties of bulk heterojunctions that consist of poly(3-hexylthiophene) (P3HT) and a methanofullerene derivative (PCBM). The post thermal annealing modifies the distribution of the P3HT and the PCBM inside the blend films, as it has been found by Spectroscopic Ellipsometry studies in the visible to far-ultraviolet spectral range. Phase separation was identified by AFM and GIXRD as a result of a slow drying process which took place after the spin coating process. The increase of the annealing time resulted to a significant increase of the P3HT crystallinity at the top regions of the blend films. [Copyright &y& Elsevier]