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A novel methodology for analyzing hybrid wind turbine-photovoltaic off-grid systems with battery storage is presented in this work. To support off-grid operation, small settlements were chosen as case studies for these autonomous hybrid systems. Μeteorological, demographic, geographical, geospatial, land use and load data with the design and implementation of off-grid power plants were used. The study aims at further supporting and improving off-grid hybrid energy systems in terms of design, analysis and integration, while a life-cycle analysis for the proposed systems was performed to quantify the relative environmental impact, as well. The findings show that the implementation of autonomous energy production by renewable energy systems for off-grid small settlements, based on the presented methodology, is feasible.

Supply chain is a crucial part of the world economy and everyday life. During the outbreak of COVID-19 in 2020, governments across the globe have tried to maintain the supply chain operations in most of the essential goods and services. Dry bulk shipping, a sector characterized by trading versatility and a multitude of cargoes carried, has an important role to play towards that aim. Port restrictions, placed to limit the spread of COVID-19, have created the impression that the market of dry bulk shipping has, to some degree, been affected and become less predictable, as many other transporting services. In this article, this belief is investigated using both state space modeling and neural networks. In particular, using these methods, one-month ahead predictions (during 2020) of the overall freight cost are obtained for three types of vessels (representing the majority of the minor bulks industry). A good forecast performance is observed and this validates the models and the estimation methods proposed. Our results suggest that there is no significant effect of COVID-19 in these types of vessels and their operations. This can provide useful information to shipping managers and policy makers.

Greece and China are two agricultural countries in which a significant percentage of their biomass consists of agricultural and livestock wastes. In Greece, the management practice that is still applied is burning the majority of the agricultural residues in the field, while in China large amount of untreated agricultural waste causes serious adverse effects on the rural living environment. Residual biomass could arise from the agricultural sector in the form of crop residues and of animal wastes. A comprehensive literature review was performed for both countries on primary agricultural and livestock wastes that includes: (a) crop residues that are left in the fields, (b) animal manures and (c) secondary agricultural wastes consisted of liquid and solid wastes from agricultural products processing plants. The average annual quantity of agricultural residues, animal manure and agro-industrial residues in Greece and China (a small and a large country, respectively) is 10 Mt/y and 860 Mt/y, 26 Mt/y and 216.5 Mt/y, 13.2 Mt/y and 213.7 Mt/y, for each corresponding category. According to the amount of the above residues generated per country, the theoretical estimated energy can reach up to 77 TWh and 5500 TWh for Greece and China, respectively, which suggests that both countries can cover a significant part of their energy needs (approximately 135% and 99%, respectively) only from their agricultural and livestock wastes. Τhese observations constitute strong recommendations mainly addressed to policy makers to substantially strengthen the efforts of research, technological and economic optimization of the applications of energy use of agricultural residual biomass for the benefit of the environment and humanity.

Agricultural residues in Greece are amounted to several million tons per year, the olive tree lops (OTL) ranked first with 1.4-3 million tons per year. After the removal of the thicker woods, the rest are burned in the countryside by farmers causing except from energy loss, particularly severe air pollution (greenhouse gases, micro particles, etc.). First objective of this study was to perform a techno-economical analysis of a complete management of OTL in a rural municipality (real application to the Municipality Department of Vasilaki in the Prefecture Laconia, Greece) for the final production of: a) leaves from OTL for extraction of useful constituents, b) bio-compost for soil enhancement and fertilizer and c) pellets for energy applications. From a sensitivity analysis, it was observed that the proposed investment was sensitive in changes of leaves value. Moreover, a change in the price of raw material alters considerably the investment. Generally, the expected profit was considered sufficient and the evaluation criteria (rate on return on initial investment, payout period and net present value) offer very promising results in the direction of undertaking the investment. As the main result, this work envisages to opening up a new road showing a feasible solution of this problem, better than that used nowadays. The proposed solution could be extended to any agricultural residue and can be applied by any interested farmer, enterprise or local authority, offering exploitation of natural resources and enhancement of agriculturist income, especially those in less favored regions.

The olive oil industry is very important in many Mediterranean countries, both in terms of wealth and tradition. The extraction of olive oil generates huge quantities of high organic wastewaters with toxic constituents that may have a great impact on land and water environments. Series of laboratory experiments, based on the technology of membrane filtration (Ultrafiltration and Nanofiltration and/or Reverse Osmosis), have been carried out for the fractionation of olive mill wastewaters into fractions with nutritive value, phytotoxic action and pure water. Based on these results, a pilot plant of membranes installed in an olive oil mill enterprise for an entire harvesting period and appropriate experiments were performed. The study showed that a fraction of pure water up to 75% can recovered and fractions that contained concentrate nutritious and polyphenol content can be isolated and further exploited in order to reduce the, indeed, high cost of the suggested treatment process. In this study, a techno-economic analysis for the implementation of the suggested method for the Region of Western Greece is presented. The present study took into account the fixed and the operational costs of the equipment, the costs for the infrastructure and land, the costs for the maintenance, etc., considering the treatment of 50,000 tones per harvesting period in the Region of Western Greece. The study showed that the establishment of one central treatment manufacture could reduce the uncontrolled disposal of OMW and their final discharging in the aqueous receptors. The exploitation of the nutritious content of the fractions as manure in fertilizers together with the polyphenol content that can be used as components of ecological herbicides can depreciate the total cost in a very short period of 1.5 years.

Reynolds-Averaged Navier Stokes (RANS) simulations are rapidly emerging and tend to become an integral part of propeller design. Moreover, modern design software like CAESES are available that allow for parametric design and shape optimization by tightly coupling the parametric geometry to computational fluid dynamics (CFD). In the present work, OpenFOAM is selected as the CFD solver and cfMesh as the grid generator. The steady state Moving Reference Frame (MRF) approximation is used to model the rotation and the turbulence is modeled using the k-ω SST model. The CFD methodology is validated on the basis of experimental results for the Potsdam Propeller Test Case (PPTC). Furthermore, a parametric model for the PPTC is created, CFD automation is achieved and the optimized counterpart is derived by modifying the radial distributions that define the blade shape. The optimization is performed using the Sobol sequence and the Tangent Search Method.

Biomass produced ashes, upon certain conditions (chemical configuration, level of fineness) can posses pozzolanic properties. Rice husk ash (RHA), an agro-industrial by-product produced of the rice industry, can be utilized successfully (in terms of concrete properties and durability indicators) as a pozzolanic material (replacing cement to a certain extend) in concrete mix design. The question is if such an endeavor is viable from an economic point of view. Such is the aim of this study. Upon a brief presentation of some of the authors’ research results on the sound viability of RHA as a cement replacement material, an assessment of the techno-economical characteristics of RHA production is taking place. Particular attention has being paid to factors as treatment process, fixed/operational cost, production cost and profit. In addition cost-benefit, short sensitivity and risk analyses were also performed aiming to evaluate the economic viability for investment on RHA pozzolanic material production and the dependence of investment characteristics on production capacity. Overall, the techno-economical analysis presented in this study provides precise demands on capital for a fixed investment, provisions for operational capital and finally provisions for revenue.

A significant step forward for a thorough durability design process of reinforced concrete structures is the development of software packages, based on predictive models, for the estimation of concrete strength and service life. Such an attempt, in full compliance with the European Standards for cement and concrete, is presented in this study. Upon defining the concrete mix design, the software calculates the main chemical and volumetric characteristics, as well as the compressive strength, of concrete. By taking into account the environmental conditions where the structure will be exposed, concrete service life is predicted, using fundamental mathematical models (based on reaction engineering principles) that simulate the reinforced concrete deterioration mechanisms leading to corrosion of the embedded reinforcement (caused by either carbonation or chloride ingress). A validation process of the yielded results is also presented, and the effectiveness of the simulation tool in designing for durability is illustrated. The goal of this study is to promote wider acceptance in achieving feasible and durable solutions to structural concrete design problems.

Considering the well known environmental issues of cement manufacturing (direct and indirect levels of CO2 emissions), clinker replacement by supplementary cementing materials (SCM) can be a very promising first step in reducing considerably the associated emissions. However, such a reduction is possible up to a particular level of SCM utilization, influenced by the rate of its pozzolanic reaction. In this study a (4-step) structured methodology is proposed in order to be able to further adjust the concrete mix design of a particular SCM, in achieving additional reduction of the associated levels of CO2 emissions and being at the same time accepted from a derived concrete strength and service life point of view. On this note, the aim of this study is twofold. To evaluate the environmental contribution of each concrete component and to provide the best possible mix design configuration, balanced between the principles of sustainability (low environmental cost) and durability (accepted concrete strength and service life ). It is shown that such a balance can be achieved, by utilising SCM by-products in the concrete mix, reducing in this way the fixed environmental emissions without compromising the long-term safety and durability of the structure.

While recognizing the problem of reinforcement corrosion and premature structural deterioration of reinforced concrete (RC) structures as a combined effect of mechanical and environmental actions (carbonation, ingress of chlorides), emphasis is given on the effect of the latter, as most severe and unpredictable action. In this study, a simulation tool, based on proven predictive models utilizing principles of chemical and material engineering, for the estimation of concrete service life is applied on an existing reinforced concrete bridge (O resund Link) located in a chloride environment. After a brief introduction to the structure of the models used, emphasis is given on the physicochemical processes in concrete leading to chloride induced corrosion of the embedded reinforcement. By taking under consideration the concrete, structural and environmental properties of the bridge investigated, an accurate prediction of its service life is taking place. It was observed that the proposed, and already used, relationship of service lifetime- cover is almost identical with a mean line between the lines derived from the minimum and maximum critical values considered for corrosion initiation. Thus, an excellent agreement with the project specifications is observed despite the different ways used to approach the problem. Furthermore, different scenarios of concrete cover failure, in the case when a coating is utilized, and extreme deicing salts attack are also investigated.

In the current study, a method for concrete compressive strength prediction (based on cement strength class), incorporated in a software package developed by the authors for the estimation of concrete service life under harmful environments, is presented and validated. Prediction of concrete compressive strength, prior to real experimentation, can be a very useful tool for a first mix screening. Given the fact that lower limitations in strength have been set in standards, to attain a minimum of service life, a strength approach is a necessity. Furthermore, considering the number of theoretical attempts on strength predictions so far, it can be seen that although they lack widespread accepted validity, certain empirical expressions are still widely used. The method elaborated in this study, it offers a simple and accurate, compressive strength estimation, in very good agreement with experimental results. A modified version of the Feret\'s formula is used, since it contains only one adjustable parameter, predicted by knowing the cement strength class. The approach presented in this study can be applied on any cement type, including active additions (fly ash, silica fume) and age.

Alargenumberofpublicationsareavailableintheliteratureregardingolivemillwastewatertreatmentmethods.However,none of the proposed methods can be considered as a best available method in terms of its effectiveness, and its environmental and economic impact. Using a literature survey, data were collected and evaluated in order for a sustainability and benchmarking analysis tobe developed.Physicochemical, biological andadvanced oxidationmethodswereevaluatedand judgedin termsof their effectiveness, environmental impact and cost. Effectiveness of each method was estimated in terms of COD and phenolic compounds reduction, environmental impact in terms of CO2 production, while for the economic impact the operational costs were taken into account. Finally, a procedure is suggested for selection of the most appropriate method based on user preferences (in terms of effectiveness, environmental impact and cost). The present analysis showed that the most effective processes in terms of organics reduction are membranefiltration, electrolysis, supercritical water oxidation and photo-Fenton. Lower environmental impact was found with anaerobic digestion, coagulation and lime processes, while the lowest cost categoryinvolvesbiocompostingandmembranefiltration,thankstotheexploitationofbyproducts(biocompostandphenolic compounds, respectively). c � 2013 Society of Chemical Industry

BACKGROUND AND PURPOSE: Imaging studies have shown that children with NF-1 have increased brain volumes compared with age-matched controls and the CCs are disproportionately large. The purpose of this study was to determine if the CC in adults with NF-1 differed from that in matched controls by using DTI and volumetric imaging. MATERIALS AND METHODS: MR imaging with DTI was performed in 10 adults with NF-1 and in 10 age-, sex-, and handedness-matched controls by using a 3T system. Total brain volumes and the areas and central lengths of the CC were calculated, along with the radial width of callosal subdivisions, in the 2 groups. RESULTS: Our results showed that the total brain volume was not significantly different between adults with NF-1 and matched controls. The length and total cross-sectional area of the CC were statistically larger in adults with NF-1 compared with controls (approximately 10% longer and 20% greater area). On DTI we found a preservation of the primary eigenvalue with increases in the minor eigenvalues at the genu. CONCLUSIONS: We have shown that the increased size of the CC found in children with NF-1 is also present in adults with the syndrome, whereas no difference in total brain volume was found.

Volcanic and geothermal areas are one of the major natural sources of H2S to the atmosphere. Its environmental impact is often the main cause of the opposition to the development of geothermal energy exploitation programs. In this paper, we analyze the air concentrations and dispersion pattern of naturally emitted H2S at the geothermal area of Sousaki (Corinthia, Greece). Measurements, made with a network of passive samplers, evidence a rapid decrease of concentration values away from the emission points. The fact that the decrease is more pronounced in the summer with respect to the winter indicates that it is not only due to a dilution effect, but also to redox reactions favored by higher temperatures and intense sunlight typical of the summer period.

To date, there is no widely accepted regulation on the minimum required diameter of the bending drums, which shape the stirrups of the main concrete reinforcing bars, varying between 4 and 12 times the diameter of the bent bar, and thus resulting in various plastic strains. In the present work, the influence of the degree of plastic strain on the mechanical properties of steel bar of Class BSt 500s for concrete reinforcement stirrups is investigated, under the additional implication of laboratory corrosive conditions. The increase of the degree of the plastic strain of the stirrup bar had as a result a significant decrease in the ductility properties of the steel. Moreover, it is shown that the combination of plastic strain and corrosion causes additional damages, as strain fractures were recorded lower than that defined by the current specifications for concrete reinforcement, indicating the need for a new review of the relative specifications.

Introduction A temporary protective loop ileostomy is a routine procedure to protect the anastomosis in patients who undergo low anterior resection for rectal cancer. The aim of this case report is to present a rare complication caused by Meckel’s diverticulum. Case presentation We describe a case of a 71-year-old white man with dysfunctional ileostomy after low anterior resection for rectal cancer due to adhesions and pressing effects of Meckel’s diverticulum near the ileostomy site, which led to volvulus of his small intestine and obstruction. As a result he underwent a supplementary operation to resolve this complication by Meckel’s diverticulum resection. Conclusions During a low anterior resection for rectal cancer and a protective ileostomy procedure the presence of Meckel’s diverticulum should not be ignored. Our proposal is the primary resection of Meckel’s diverticulum as the best surgical choice; according to the limited international literature on such cases we report a possible alternative to a protective ileostomy by creating a conduit using Meckel’s diverticulum as a stoma.

This work describes the implementation of two-coil continuous arterial spin labeling (CASL) using a single RF channel and amplifier, avoiding the need for costly additional hardware—namely, a second 1H RF channel and amplifier dedicated to the labeling coil. This is possible in principle, as labeling and imaging RF pulses are never applied simultaneously in the CASL pulse sequence. Simple and inexpensive electronics, together with minor pulse programming modification, were used to create the waveforms (TTL and RF pulses) necessary to drive the two coils. A custom-built RF switch of single-pole double-throw (SPDT) design alternated the output of the RF amplifier between the imaging and labeling coils. Bipolar bias waveforms controlled the switch and also provided active decoupling between the two coils. These waveforms were created from the original TTL waveform, which gated the RF amplifier, using a flip-flop. The method was implemented in a small-bore MRI scanner and enabled good-quality CASL measurements of functional cerebral blood flow changes during whisker electrical stimulation. © 2006 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 29B: 145–152, 2006

Sustainable development of the building sector can be achieved by a significant incorporation of cementitious and pozzolanic by-products, such as fly ash and slag, as well as some natural pozzolanic materials (supplementary cementing materials--SCM). Millions of tons of SCM, especially in Greece, are dumped due to overproduction or non-conformity with the existing standards. In this work, various types of SCM produced in Greece are investigated for a potential use in concrete. Their behavior as regards strength and durability is approached by a practical efficiency factor (k-value). The work is further focused on fly ashes, as they constitute the vast and more active majority of Greek SCM. The effectiveness of the Greek fly ashes in concrete improvement is widely proved through strength and durability measurements at laboratory and pilot-plant scale. However, they contain high amounts of free lime and sulphates, which may cause durability problems. In addition, they exhibit inadequate fineness and composition variations. Thus, an appropriate treatment is required and proposed by the present study in order to eliminate or reduce any harmful factors. Finally, a mix design strategy ensuring optimum strength, durability and ecological profile is proposed. (A) "Reprinted with permission from Elsevier".

This paper describes a method for correcting eddy-current (EC)-induced distortions in diffusion-weighted echo-planar imaging (DW-EPI). First, reference measurements of EC fields within the EPI acquisition window are performed for DW gradient pulses applied separately along each physical axis of the gradient set and for a range of gradient amplitudes. EC fields caused by the DW gradients of the DW-MRI protocol are then calculated using the reference EC measurements. Finally, these calculated fields are used to correct the respective DW-EPI raw (k-space) data during image reconstruction. The technique was implemented in a small-bore MRI scanner with no digital preemphasis. It corrected EC-induced image distortions in both phantom and in vivo brain diffusion tensor imaging (DTI) data more effectively than commonly used image-based techniques. The method did not increase imaging time, since the same reference EC measurements were used to correct data acquired from different phantoms, subjects, and DTI protocols. Because of the simplicity of the reference EC measurements, the method can easily be implemented in clinical scanners.

Background: High angular resolution diffusion tensor imaging (HARD) is an MRI technique that exploits the mobility of water molecules to yield maps of structural order and directionality of white matter tracts with greater precision than six-direction diffusion tensor imaging (DTI) schemes. Objective: To assess whether HARD is more sensitive than conventional MRI or neurologic assessment in detecting the upper motor neuron (UMN) pathology of patients with ALS. Methods: Twenty-five patients with definite UMN clinical signs and 23 healthy volunteers underwent conventional MRI. HARD datasets were collected from a subset of these participants plus four patients with isolated lower motor neuron (LMN) signs. ALS symptom severity was assessed by a neurologist, the conventional MR images were reviewed by neuroradiologists, and the DTI maps were subject to quantitative region of interest analysis. Results: Motor cortex hypointensity on T2-weighted images and corona radiata hyperintensity on proton density-weighted images distinguished patients with UMN involvement from volunteers with 100% specificity, but only 20% sensitivity. Fractional anisotropy (FA) was reduced in the posterior limb of the internal capsule in patients with UMN involvement compared to volunteers. A FA threshold value with a sensitivity of 95% to detect patients with ALS (including those with isolated LMN signs) had a specificity of 71%. Conclusions: High angular resolution diffusion tensor imaging may be more sensitive than conventional MRI or neurologic assessment to the upper motor neuron (UMN) pathology of ALS, but it lacks the specificity required of a diagnostic marker. Instead, it is potentially useful as a quantitative tool for monitoring the progression of UMN pathology.

Background We tested the hypothesis that depletion of neutrophil leukocytes from the cardioplegic and the initial myocardial reperfusion perfusates reduces clinical indices of reperfusion injury in patients undergoing elective coronary artery bypass. Methods We studied 160 consecutive patients who underwent standard coronary revascularization with cardiopulmonary bypass. Patients with recent myocardial infarction or coronary angioplasty were excluded. Cold blood cardioplegia was used. Just before aortic unclamping, the hearts were perfused retrograde with 250 mL of normothermic cardioplegic solution and 750 mL of blood (pump perfusate). Patients were randomly assigned to two groups. In 80 patients (treated), neutrophils and platelets were removed from all cardiac perfusate during aortic crossclamping with leukocyte filtration. In the remaining 80 patients (control group), leukocyte filtration was not used. Results There was no significant difference between groups in age, sex, severity of disease, and number of bypass grafts implanted. Treated patients showed lower prevalence of low cardiac index and reperfusion ventricular fibrillation and lower levels of creatinine kinase MB isoenzyme and troponin I early postoperatively ( p Conclusions Neutrophil-filtered blood cardioplegia/reperfusion significantly reduced clinical and biochemical indices of myocardial reperfusion injury after elective coronary revascularization with cardiopulmonary bypass.

Background We evaluated the newly introduced Bioline heparin coating and tested the hypothesis that surface heparinization limited to the oxygenator and the arterial filter will ameliorate systemic inflammation and preserve platelets during cardiopulmonary bypass (CPB). Methods In a prospective double-blind study, 159 patients underwent coronary revascularization using closed-system CPB with systemic heparinization, mild hypothermia (33°C), a hollow-fiber oxygenator, and an arterial filter. The patients were randomly divided in three groups. In group A (controls, n=51), surface heparinization was not used. In group B (n = 52), the extracorporeal circuits were totally surface-heparinized with Bioline coating. In group C (n = 56), surface heparinization was limited to oxygenator and arterial filter. Results No significant difference was noted in patient characteristics and operative data between groups. Operative (30-day) mortality was zero. Platelet counts dropped by 12.3% of pre-CPB value among controls at 15 minutes of CPB, but were preserved in groups B and C throughout perfusion ( p = 0.0127). Platelet factor 4, plasmin-antiplasmin levels, and tumor necrosis factor-α increased more in controls during CPB than in groups B or C ( p = 0.0443, p = 0.0238 and p = 0.0154 respectively). Beta-thromboglobulin, fibrinopeptide-A, prothrombin fragments 1 + 2, factor XIIa levels, bleeding times, blood loss, and transfusion requirements were similar between groups. Intensive care unit stay was shorter in groups B and C than in controls ( p = 0.037). Conclusions Surface heparinization with Bioline coating preserves platelets, ameliorates the inflammatory response and is associated with a reduced fibrinolytic activity during CPB. Surface heparinization limited to the oxygenator and the arterial filter had similar results as totally surface-heparinized circuits.

Angiosarcomas are rapidly growing malignant neoplasms arising from the vascular endothelial cells. Most common sites are the extremities and the retroperitoneal space, with only four per cent of angiosarcomas arising in the head and neck area, whilst the paranasal sinuses are one of the rarest locations. We report the case of a maxillary sinus angiosarcoma in a 72-year-old male patient. The first biopsy was inconclusive, whereas the second revealed an angiosarcoma. Medial maxillectomy was performed with subsequent external irradiation.

This article describes a method which enables fast and objective pulse-sequence-specific preemphasis calibration, using standard pulse sequences and system hardware. The method is based on a k-space measurement technique, and has been applied to single-shot, diffusion-weighted, spin-echo, echo-planar imaging (DW-SE-EPI), which is particularly sensitive to eddy-current-induced image distortions. The efficiency of the technique was demonstrated not only by the reduction of eddy-current fields to a negligible level using full preemphasis compensation, but also by the fact that adjustment of the slow time-base alone sufficed for the practical elimination of image distortions in the DW-SE-EPI images and the subsequent diffusion tensor maps (in a phantom and a human brain). By seeking to eliminate directly the effect of eddy-current-induced phase shifts during the EPI data collection, the method is free of the complications and restrictions associated with other eddy-current correction techniques for DW-SE-EPI (such as acquisition of additional calibration scans, intense postprocessing, extensive pulse-sequence modifications), making their use redundant.

SUMMARY Progressive bulbar palsy is very rare in childhood. A probable case diagnosed in Greece is presented. After a short review of the literature the clinical and laboratory findings are described. The main clinical features were progressive affection of the bulbar nuclei over one year without involvement of the long tracts. The laboratory findings practically excluded conditions with a similar clinical picture. No autopsy was performed, so the diagnosis remains unproved.

In Venezuela, the idea of tiering information between land-use ordering instruments and impact assessment is absent. In this article we explore a methodological alternative to bridge the information presented in land-use ordering instruments with the information requirements for impact assessment. The methodology is based on the steps carried out for an environmental impact assessment as well as on those considered to develop land-use ordering instruments. The methodology is applied to the territorial ordering plan and its proposal for the protection zone of the Cataniapo River basin. The purpose of the protection zone is to preserve the water quality and quantity of the river basin for human consumption.

The extraction of olive oil generates huge quantities of solids and of high organic wastewaters with toxic constituents that have a great impact on land and water environments. Based on a membrane process, authors proposed an alternative method for treatment of olive mill wastewaters (OMWs). In the present paper, a technoeconomic analysis for the implementation of the proposed method in the entire Region of Western Greece (RWG) is presented. This paper takes into account fixed and operational costs, costs for the infrastructure, equipment, land, maintenance, and so forth, considering the treatment of 50,000 tons per harvesting period in the area of RWG. The study showed that the establishment of only one central treatment manufacture could reduce the uncontrolled disposal of OMW. Exploitation of the isolated fractions as manure in fertilizers (nutrients components) or as components in ecological herbicides (phenolics) can depreciate the total cost in a period of about five years.

The Organic Rankine Cycle (ORC) appears progressively as a promising solution to recover waste heat energy from thermal processes for electricity generation. A prototype of small-scale ORC has been built and successfully tested at the University of Liege. It uses R-245fa and R-123 as working fluid, and an oil-free scroll compressor adapted to run in expander mode. Thermodynamic model of the system was derived and validated for performance prediction. The validated thermodynamic model is used to optimize the operation of the small ORC in waste heat recovery application (ORC-WHR). For exhaust gases at 180 °C and a mass flow rate of 0.21 kg/s, a maximum net power output of 2 kWe is obtained for an evaporator pressure of 11.84 bar. The cycle thermal efficiency is 8.23 and the recuperation efficiency, 66.32%. Based on the aforementioned conditions, the economic assessment of small scale ORC-WHR was carried out using economic criteria such as levelized electricity cost (LEC), Net present value (NPV) and depreciated payback period (DPP). For a 2kWe ORC-WHR, the specific installed cost is 5775 €/kW with a LEC of 13.27 c€/kWh while for a 50 kWe, the specific installed cost is about 3034 €/kW and the LEC, 7c€/kWh. For an electricity unit price of 20 c€/kWh, the payback period of a 2 kWe system is 6 years while it is 2.5 years for a 50 kWe system. It is concluded from the study that recovering the waste heat by way of ORCs is technically and economically feasible. As recycled energy, waste heat has the same advantages as renewable energy and should benefit from the same legislative conditions (Feed-in-Laws).Copyright © 2010 by ASME

Background and objectives: This study examined the efficacy of C.E.R.A., a continuous erythropoietin receptor activator, for correcting anemia in patients who had chronic kidney disease (CKD) and were not on dialysis. Design, setting, participants, & measurements: In this open-label, randomized, parallel-group, Phase III study, 324 adult patients with CKD not on dialysis nor receiving treatment with erythropoiesis-stimulating agents (ESAs) were randomly assigned (1:1) to receive subcutaneous C.E.R.A. once every 2 wk or darbepoetin alfa once weekly during an 18-wk correction period and a 10-wk evaluation period. Thereafter, patients receiving C.E.R.A. were randomly assigned to C.E.R.A. once every 2 wk or once monthly, and patients receiving darbepoetin alfa could receive darbepoetin alfa once weekly or once every 2 wk for a 24-wk extension period. Dosage was adjusted to achieve a hemoglobin (Hb) response and to maintain Hb ±1 g/dl of the response level and 11 to 13 g/dl. Primary end points were Hb response rate during correction and evaluation and change in Hb concentration between baseline and evaluation. Results: Hb response rates were 97.5% for C.E.R.A. and 96.3% for darbepoetin alfa. Adjusted mean changes in Hb from baseline to evaluation were 2.15 g/dl (C.E.R.A.) and 2.00 g/dl (darbepoetin alfa). Analysis showed that C.E.R.A. once every 2 wk was as effective as darbepoetin alfa once weekly for correcting anemia. Hb levels remained stable in all groups during the extension period. C.E.R.A. and darbepoetin alfa were well tolerated. Conclusions: Subcutaneous C.E.R.A. once every 2 wk corrects anemia in ESA–naive patients who are not on dialysis.

Vortex particles methods are applied to the aeroelastic simulation of a wind turbine in sheared and turbulent inflow. The possibility to perform large-eddy simulations of turbulence with the effect of the shear vorticity is demonstrated for the first time in vortex methods simulations. Most vortex methods formulation of shear, including segment formulations, assume a frozen shear. It is here shown that these formulations omit two source terms in the vorticity equation. The current paper also present unfrozen simulation of shear. The infinite support of the shear vorticity is accounted for using a novel approach relying on a Neumann to Dirichlet map. The interaction of the sheared vorticity with the wind turbine is shown to have an important impact on the wake shape. The obtained wake shape are closer to the one obtained using traditional computational fluid dynamics: Results with unfrozen shear do not have the severe upward motion of the wake observed in vortex methods simulation with frozen shear. The interaction of the shear and turbulence vorticity is shown to reduce the turbulence decay otherwise observed. The vortex code implemented is coupled to an aeroelastic code and examples of aeroelastic simulations under sheared and turbulent inflow are presented.

Background Primary non-Hodgkin lymphomas (NHLs) of the sinonasal tract comprise a rare entity that constitutes 1.5% of all NHLs and 2.2% of extranodal lymphomas in the whites. Clinical diagnosis may be very challenging because of the variety and low specificity of the presenting symptoms and signs. Methods-results We present three cases of NHLs, initially diagnosed as benign diseases. All three cases have been eventually correctly diagnosed and treated in our hospital between January 2000 and December 2003. The patients have been under close follow-up from 11 to 36 months after the initial treatment. One of them remains without clinical or radiological evidence of recurrence, whereas the two others died 11 and 16 months after the initial diagnosis. Conclusion It is important to underline that atypical or persistent symptoms of rhinosinusitis may represent the initial expression of a more serious condition such as deep fungal infection, vasculitis, lymphoma, or other malignancy.

We tested the hypothesis that leukocyte filtration during pulmonary reperfusion preserves pulmonary function and results in improved oxygenation after cardiopulmonary bypass (CPB) in patients with chronic obstructive pulmonary disease (COPD).In a prospective, randomized study, the treatment group consisted of 20 patients with COPD from consecutive open-heart procedures. A primed leukocyte filter was connected to the arterial line downstream of the standard arterial filter but was excluded from circulation. Circulated blood was directed through the leukocyte filter approximately 10 minutes before aortic cross-clamp removal and at early reperfusion for up to 30 minutes. These patients were compared to 20 additional COPD patients (controls) on whom systemic leukocyte filtration was not used during open-heart surgery.There was no significant difference in gender, age, left ventricular ejection fraction, type of procedure, aortic cross-clamp time, perfusion time, preoperative FEV1 and preoperative respiratory index (Pao2/FiO2 ratio) between treatment and control groups. The respiratory index changed in the treatment group by +9.8% of baseline after completion of CPB, by -14.2% upon arrival in the intensive care unit (ICU), and by -19.6% 12 hours later, whereas in the control group, it changed by -14.5% (p0.05), -27.7%, and -24%, respectively. Leukocyte-depleted patients required shorter intubation time (20.4 +/- 16.1 hours), ICU stay (46.2 +/- 40.1 hours) and length of hospitalization (8.3 +/- 2.8 days) than controls (29.5 +/- 21.9 hours, p0.05; 75.5 +/- 34.9 hours, p0.005; and 10.4 +/- 3.5 days, p0.05, respectively). Surgical (30-day) mortality was zero in both groups.In COPD patients having CPB, systemic leukocyte depletion at early reperfusion was associated with better oxygenation, shorter intubation time, and shorter ICU and hospital stays. Leukocyte filtration during CPB most likely preserves pulmonary function by ameliorating pulmonary reperfusion injury.

The phase, as well as the magnitude, of MRI images can carry useful information. It may be used to encode flow or temperature, or to map the magnetic field for the undistorting of EPIs and automated shimming. In all cases, we measure the extra spin given to nuclei. Unfortunately, we can only measure the final phase of the spins: the rotation is wrapped into the range [−π, +π], and to obtain a measure of the parameter of interest the missing multiples of 2π must be replaced—a process known as phase unwrapping. While simple in principle, standard phase unwrapping algorithms fail catastrophically in the presence of even small amounts of noise. Here we present a new algorithm for robust three-dimensional phase unwrapping, in which unwrapping is guided, so that it initially works on less noisy regions. We test the algorithm on simulated phase data, and on maps of magnetic field, which were then used to successfully undistort EPI images. The unwrapping algorithm could be directly applied to other kinds of phase data.

Recent advances in MR diffusion weighted imaging (DWI) enable the identification of anisotropic white matter tracts with diffusion tensor imaging (DTI). We aimed to use a novel DTI technique to safely study patients with recent stroke in a high field (3 T) MR machine with its intrinsically higher spatial resolution and signal-to-noise ratio. Of ten patients studied, six had disruption of white matter tracts as determined by DTI. A further patient had distortion of white matter tracts around an infarct rather than actual disruption of the tracts themselves. The lack of tract destruction may imply a beneficial prognosis, information that is not available with conventional DWI.

The present paper aims at formulating a mathematical model for the formation and motion of the slag layer caused by the sticking of molten ash particles on furnace walls. The Navier-Stokes equations are simplified bearing in mind the creeping type of flow. The model was first applied to simple cases and then to the Westinghouse Pressurised Pulverised Coal Combustor (p.p.c.c). The conditions on the slag surface (such as shear stress, pressure distribution and particle deposition rate) were either assumed a given value or provided by the “parent” code CO.C.A. 3 (Coal Combustion Algorithm in 3-D). The results show that the thickness of the slag layer in the p.p.c.c. is very small (approximately 1-1.5 mm) and agrees well with the observed value reported by Westinghouse. Also, the slag velocity is small enough (about 4-5 mm/s) for the slag layer to be considered as a wall for the gas phase calculations.

Terrestrial ecosystems consist of plants, bioraass producers, and man, animals and microorganisms which feed on plants and their residues. Plant development and decomposition take place within the soil system, thus it may be said, that soil is among the main supporters of life and important regulator of man’s physiological processes.

The histocompatibility antigen HLA-B27 was identified in 12 out of 33 patients with acute non-granulomatous anterior uveitis. This is a frequency of 36.36%, compared with 4.72% in controls. Seven patients had in addition evidence of systemic disease, including ankylosing spondylitis, sacroiliitis, Reiter's disease, Still's disease, and rheumatoid arthritis. Five of these were HLA-B27 positive, which suggests that the uveitis in many of these cases has a similar aetiology to the uveitis in those with rheumatic disease. It appears that the more severe cases of acute anterior uveitis are related more frequently to the presence of HLA-B27.

We report one case of esophagopleural fistula occurring after right pneumonectomy. Pathogenesis and management of this complication are briefly discussed. Drainage of the empyema and direct closure of the fistula, with coverage by a pedicle flap of the intercostal muscle are the best methods of treatment.

Ninety-one cases of hydatid disease of the chest are reported. Eighty-eight were involving the lung, two the chest wall, and one the mediastinum. All the patients were treated surgically. Conservative operations (simple removal of the parasite and closure of the remaining cavity) were performed in 78 patients, 37 unruptured and 41 ruptured cysts. Late postoperative complications occurred in eleven. In 10 patients, recurrent haemoptysis was the main symptom due to residual cavity in four, bronchiectatic changes in two, and unknown aetiology in four. In one patient, recurrence of multiple cysts occurred in the affected lobe. Radical operations were carried out in 10 patients, including segmental resection in four and lobectomy in six. Conservative operations were performed in all cases of unruptured cysts, with the exception of a giant cyst in which resection was the operation of choice. For ruptured cysts with mild infection conservative operation was also performed. Resection was necessary only in patients with ruptured cysts with suppuration, bronchiectatic changes, and giant cysts replacing a whole lobe. There was no mortality. We believe that conservative operation is the treatment of choice for hydatid disease of the lung. Indications for resection are very limited.