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Exergy as a measure of useful work can be used in the design, simulation and performance evaluation of different energy systems. In this paper it is investigated the Serbian residential building with photovoltaics and solar collectors on the roof, and with three different heating systems: electrical heating, district heating and central heating with gas boiler. Exergy optimization was performed with the aim to determine the optimal area of the PV array and solar collectors on the roof (including embodied exergy). With these values, the maximum exergy efficiency of installed solar systems is obtained, and building primary energy consumption is minimized. The residential buildings with variable temperature in domestic hot water system, variable PV cell efficiency and variable hot water consumption are investigated in order to achieve positive-net energy building. The buildings were simulated in EnergyPlus software and Genopt was used for software execution control during optimization. The obtained results show that positive-net energy building with optimally sized photovoltaics and solar collectors', can be achieved in a case of gas heating system, and in the cases of PV cell efficiency of 14% and 16%. Also, an environmental and economic analysis of the most favourable solutions from exergetic optimization was performed. Total CO 2 emission (with embedded emissions of CO 2) increases with increasing amount of generated energy – for PV system of cell efficiency of 12%, 14% and 16%, total CO 2 emission of solar systems is 20.8 kg CO 2 /m2, 23.5 kg CO 2 /m2 and 26.2 kg CO 2 /m2, respectively. The emission payback time decreases with increasing PV cell efficiency from 1.11 to 1.04 years. With the increase of PV cell efficiency, there is an increase in the annual financial profit (from 1518 to 4305 €), while at the same time, the investment payback period decreases (from 16.9 to 6.1 years). Best results are obtained for the building with gas heating system. • Exergy efficiency optimization of photovoltaic and solar collectors in order to determine fraction of PV panels on the roof. • Minimizing primary energy consumption and achieving the Positive net-energy building. • Variable: hot water temperature, PV cell efficiency and hot water consumption. • Environmental analysis of solar systems. • Financial profit and investment payback period of solar system. [ABSTRACT FROM AUTHOR]

It has been suggested that unerupted lower third molars (M3) increase the fragility of the mandibular angle and simultaneously decrease the risk of condylar fracture. However, it is unknown whether this applies regardless of the direction and point of impact of the traumatic force. The aim of this study was to investigate the impact of an unerupted M3 on the fragility of the angle and condyle in terms of a force acting from different directions and affecting different regions of the mandible. Computed tomography scans of a human mandible and finite element methodology were used to obtain two three-dimensional models: a model with, and the other without an unerupted M3. A force of 2000 N was applied to three different regions of the models: the symphysis, ipsilateral body, and contralateral body, respectively. When the force was applied to the mandibular body, the results revealed increased angle fragility in cases with unerupted M3. When the force was applied to the symphysis, the condyle region showed higher fragility, irrespective of the presence of an unerupted M3. In summary, fragility of the angle and condyle regions depends on the presence of an unerupted M3 and on the direction and point of impact of the force. [ABSTRACT FROM AUTHOR]

Abstract: A new technology for radionuclide trapping which is based on bio-templating approach was proposed in this paper. Porous oxide ceramics was prepared by wet impregnation of biological template with water solution of cerium and strontium nitrates. The template was derived from linden wood (tilia amurensis). Repeated pressure impregnation, heat treatments and final calcination at 1000°C in air resulted in the template burnout and consolidation of the oxide layers. The obtained products had structure which corresponded to the negative replication of biological templates. X-ray diffraction, scanning electron microscopy, Raman spectroscopy and porosimetry were employed to characterize the composition and structure of biomorphic ceramics. It was found that the wood impregnated with water solution of cerium and strontium nitrates was converted into oxide ceramics (Ce0.9Sr0.1O2−δ ), while preserving the microstructural features of the biological preform. [Copyright &y& Elsevier]

Methanol is usually produced in large amounts in fixed-bed reactors under steady-state conditions using Cu/ZnO/Al 2 O 3 -catalyst. In this paper, possible improvements through forced periodic operation compared to optimal steady-state solution are investigated. The numerical study is done with a simplified model which describes a hypothetical 7-meter-long isothermal and isobaric fixed-bed reactor. The forced periodic operation is implemented using harmonic forcing and square-waves. Multi-objective optimization is performed for different operating conditions quantifying the achievable molar flow rate of methanol at the reactor outlet and the yield of methanol based on total carbon. The resulting PDE-constrained optimization problems are solved using a simultaneous approach, with orthogonal collocation as discretization. The results show most significant improvements through forced periodic operation with square-waves. The periodic operation can provide theoretical improvements of up to 50% for the methanol mean outlet molar flow rate and improvements of up to 10% for the yield based on total carbon. • Forced periodic operation theoretically improves the performance of methanol synthesis in fixed-bed reactors • Square-wave modulation provides more significant improvement than harmonic modulation • Less hydrogen is needed with forced periodic operation compared to steady-state operation • Orthogonal collocation is used to discretize the partial differential equation. [ABSTRACT FROM AUTHOR]

Biomarkers capable of reflecting disease onset and short- and long-term therapeutic effects in individuals with spinal muscular atrophy (SMA) are still an unmet need and phosphorylated neurofilament heavy chain (pNF-H) holds significant promise. We conducted a longitudinal prospective study to evaluate pNF-H levels in the cerebrospinal fluid (CSF) and plasma of 29 individuals with childhood-onset SMA treated with Nuinersen (SMA type 1: n=6, type 2: n=17, type 3: n=6). pNF-H levels before and during treatment were compared with the levels of controls (n=22), patients with Duchenne muscular dystrophy (n=17), myotonic dystrophy type 1 (n=11), untreated SMA individuals with chronic type 3 disease (n=8), and children with presymptomatic SMA (n=3). SMA type 1 showed the highest mean CSF pNF-H levels before treatment initiation. All Nusinersen-treated individuals (types 1, 2, and 3) showed significantly elevated mean baseline CSF pNF-H compared to controls, which inversely correlated with age at disease onset, age at first dose, disease duration and the initial CHOP INTEND result (for SMA type 1 and 2). During 22 months of treatment, CSF pNF-H levels declined during loading doses, stabilizing at reduced levels from the initial maintenance dose in all individuals. Baseline plasma pNF-H levels in type 1 and 2 SMA were significantly increased compared to other cohorts and decreased notably in type 1 after 2 months of treatment and type 2 after 14 months. Conversely, SMA type 3, characterized by lower baseline pNF-H levels, did not show significant fluctuations in plasma pNF-H levels after 14 months of treatment. Our findings suggest that CSF pNF-H levels in untreated SMA individuals are significantly higher than in controls and that monitoring of CSF pNF-H levels may serve as an indicator of rapid short-term treatment response in childhood-onset SMA individuals, irrespective of the subtype of the disease, while also suggesting its potential for assessing long-term suppression of neurodegeneration. Plasma pNF-H may serve as an appropriate outcome measure for disease progression and/or response to treatment in types 1 and 2 but not in type 3. Clinically silent infants with SMA may show elevated pNF-H levels, confirming early neuronal degeneration. [ABSTRACT FROM AUTHOR]

Objectives: To analyze the predictive value of anti-acetylcholine receptor antibodies (anti-AChR Ab) and anti-muscle specific kinase antibodies (anti-MuSK Ab), as well as the thymus pathology to the clinical outcome in patients with generalized myasthenia gravis (MG). Methods: We analyzed 138 patients with generalized MG, who were thymectomized and assayed for anti-AChR Ab and anti-MuSK Ab. Results: Anti-AChR Ab were detected in 84% of patients, while anti-MuSK Ab were present in 36% of the AChR Ab negative patients. Severe forms of the disease were more frequent in MuSK Ab positive, compared to the AChR Ab positive and complete seronegative patients. Thymic lymphoid follicular hyperplasia (LFH) was present in 60%, thymoma in 23%, atrophic thymus in 9% and the normal thymus in 8% of patients. LFH was more frequent among women, while thymoma and atrophic thymus were more frequent in men. The younger patients mainly had LFH and normal thymus, while thymoma and atrophic thymus were more frequent in older patients. The mildest clinical presentation was present in patients with normal thymus, while severe forms of the disease were registered in the patients with thymoma. The AChR Ab positive patients had more often LFH and thymoma, while within MuSK Ab positive patients atrophic thymus was most common. Conclusion: The best disease outcome was observed in patients with normal thymus or LFH with anti-AChR Ab or without both types of antibodies. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have suggested that the multiple transplants might be equally metabolically efficient to a single regimen for human adult islets. The aim of this study was to compare immunological and metabolic parameters after each of the two regimens of human fetal islets (HFI). Group A single transplants (n = 9) had 180 ± 20 × 1000 HFI equivalents (IEQs) implanted via a single intramuscular injection. In group B multiple transplants (n = 8) islets were implanted by three consecutive injections of 60 ± 10 × 1000 IEQs at 7-day intervals. We analyzed the immunological parameters of CD4/CD8 T lymphocyte ratios; islet cell antibodies (ICAs) and insulin antibodies (IAs). We estimated insulin secreting capacity (ISC) as the metabolic parameter. We observed that the CD4 +/CD8 + T-cell ratio increased, peaking on day 90, in similar fashion in both groups: day −1: A = 1.18 ± 0.03 versus B = 1.19 ± 0.04; on day 90: A = 1.79 ± 0.09, versus B = 1.75 ± 0.08 (P = NS) immediately before the decrease in C-peptide levels. Thereafter the ratios rapidly decreased without statistical differences. The levels of ICAs did not change. The levels of IAs, which were increased before transplant, then decreased without statistical differences between the groups. The values of ISC increased after transplant and then decreased similar to the T-cell ratio. Our results demonstrated that regimens of multiple and single HFIs did not show differences in the kinetics of the immunological response presumably mediating graft destruction. The CD4/CD8 ratio increased as the C-peptide level decreased, peaking on day 90 at the time of a decrease in C-peptide. These results may be useful for clinical studies of HFIs for type 1 diabetic patients. [Copyright &y& Elsevier]

Abstract: This paper presents PM10 fugitive dust emission factors for a range of vehicles types and examines the influence of vehicle and wake characteristics on the strength of emissions from an unpaved road. Vertical profile measurements of mass concentration of the passing plumes were carried out using a series of 3 instrumented towers. PM10 emission fluxes at each tower were calculated from knowledge of the vertical mass concentration profile, the ambient wind speed and direction, and the time the plume took to pass the towers. The emission factors showed a strong linear dependence on speed and vehicle weight. Emission factors (EF=grams of PM10 emitted per vehicle kilometer traveled) ranged from approximately EF=0.8×(kmh−1) for a light (∼1200kg) passenger car to EF=48×(kmh−1) for large military vehicles (∼18000kg). In comparison to emission estimates derived using US EPA AP-42 methods the measured emission factors indicate larger than estimated contributions for speeds generally>10–20kmh−1 and for vehicle weights>3000kg. The size of a wake created by a vehicle was observed to be dependent on the size of the vehicle, increasing roughly linearly with vehicle height. Injection height of the dust plume is least important to long-range transport of PM10 under unstable conditions and most important under stable atmospheric conditions. [Copyright &y& Elsevier]

Abstract: Previous studies suggest that multiple transplantations might be equally efficient to a single regimen for human adult islets. The aim of this study was to compare metabolic parameters after each of the two regimens of human fetal islet (HFI) transplantation in type 1 diabetics. In group A (single transplant, n = 9), 180 ± 20 × 1000 HFI equivalents (IEQs) were implanted by a single IM injection; in group B (multiple transplants, n = 8) islets were implanted as three consecutive injections (60 ± 10 × 1000 IEQs) at 7-day intervals. We analyzed the metabolic parameters on days −1, 30, 60, 90, 120, 150, and 180 after the procedure. Among the metabolic parameters, we evaluated insulin secretion capacity-ISC (C peptide, RIA), metabolic control (HbA1c, chromatography), and insulin daily dose IDD. We found that C peptide levels increased, peaking on day 90 (A: 0.38 ± 0.15; B: 0.34 ± 0.19 nmol/L, P = NS) and then rapidly decreasing without differences, the HbA1c levels and IDD decreased in the same manner without differences between the groups. Our results demonstrate that multiple and single islet transplant regimens are equally efficient to temporarily restore a significant ISC with improvement of metabolic and clinical parameters. The results imply that the two regimens have an equal clinical value. [Copyright &y& Elsevier]

The formation of atoms by recombination of free electrons with ions is a fundamental process and plays a central role in astro-physical and fusion plasmas. It can be seen as time-inverse photo-ionization, auto-ionization, or electron-impact ionization. Here, we show how these processes can be measured with cooler-storage rings, such as CRYRING at MSL, with very high accuracy. The status of theoretical modeling is briefly reviewed and anomalies are uncovered. We discuss some examples of recombination for ions where strong dielectronic recombination resonances occur. With cooler-storage rings, these resonances can today be measured with meV accuracy, and from the spectra of the dielectronic resonances, very accurate values for energy splittings and resonance strengths are derived. These allow crucial tests of relativistic, correlation, and QED effects in these systems. [Copyright &y& Elsevier]