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Abstract In this work, a simulation tool for an integrated temperature swing adsorption (TSA) carbondioxide ( CO 2 ) capture process is introduced and used to study the feasibility of the process for biogas upgrading applications. The TSA process consists of interconnected multi-stage fluidized bed columns and utilizes solid amine sorbents for selective adsorption of CO 2 . The simulation tool has been developed in the process simulation software IPSEpro™ and performs mass- and energy balance calculations that are based on a suitable adsorption equilibrium model. Changes of the adsorbent CO 2 loadings and the corresponding heating or cooling requirements are calculated for the individual fluidized bed stages of the adsorber and desorber column. The adsorption equilibrium calculations have been performed, using a Langmuir model that was fitted to CO 2 adsorption data of an amine functionalized solid sorbent material. Within this work, the qualitative impact of the regeneration temperature and the stripping gas feeding rate on the overall process performance has been studied. Furthermore, the feasibility for integration of a high temperature compression heat pump (HP) has been assessed. The HP recovers heat from the adsorber to drive adsorbent regeneration within the desorber. Results obtained from this work clearly indicate a great potential of the multi-stage fluidized bed TSA process for biogas upgrading, especially in combination with the proposed heat pump configuration. Highlights • Innovative temperature swing adsorption model for biogas upgrading. • Simulation of a fully continuous fluidized bed TSA process. • Energy results of the proposed TSA process for biogas upgrading in terms of active cooling/heating and electricity supply. • Integrated heat pump concept enables potential energy efficiency. [ABSTRACT FROM AUTHOR]

Background: Catheter-based pulmonary vein (PV) isolation has emerged as established therapy for patients with paroxysmal atrial fibrillation (AF). Objective: The purpose of this study was to determine the results at 1-year follow-up after PV isolation was performed using a single novel multipolar catheter for mapping and ablation. Methods: Patients with paroxysmal AF were screened by cardiac computed tomography for anatomic suitability to undergo PV ablation with the Bard HD Mesh Ablator Catheter (MESH). PV isolation with the MESH was performed only in patients who matched the criteria of four clearly separated PVs with an ostial diameter of 15 to 25 mm. Results: PV isolation with the MESH was performed in 36 (55%) of 65 screened patients. In all 36 patients, all PVs could be mapped with the MESH. Electrical isolation could be achieved in 135 (96%) of 140 PVs that revealed PV potentials. One-year follow-up was completed for 35 patients; one patient was lost to follow-up. Ten (29%) patients reported to be symptom-free and had no AF during three 48-hour ECGs, whereas 25 (71%) patients suffered from AF recurrences. Reablation performed in 11 patients revealed reconnection of three PVs in 6 patients and four PVs in 5 patients. Conclusion: The single-catheter approach using the MESH for mapping and ablation was associated with a high AF recurrence rate within the first year despite a high acute success rate. Thus, the minimalist complexity of the procedure must be balanced with the poor clinical success leading to a high number of second procedures. [ABSTRACT FROM AUTHOR]

The drinking water industry is continually seeking innovative disinfection strategies to control biofouling in transmission systems. This research, conducted in collaboration with the East Bay Municipal Utility District (EBMUD) in California, compared the efficacy of chlorine dioxide (ClO2) to free chlorine (Cl2) with and without pre-treatment with low-pressure ultraviolet (UV) light for biofilm control. An additional goal was to determine disinfection by-product (DBP) formation with each disinfection strategy. Annular reactors (ARs) containing polycarbonate coupons were used to simulate EBMUD''s 90-mile aqueduct that transports surface water from a source reservoir to treatment facilities. ARs were dosed with chemical disinfectants to achieve a residual of 0. 2mg/L, which is a typical value mid-way in the aqueduct. The experiment matrix included four strategies of disinfection including UV/ClO2, ClO2, UV/Cl2 and Cl2. Two ARs acted as controls and received raw water (RW) or UV-treated water. The data presented show that the UV/ClO2 combination was most effective against suspended and attached heterotrophic (heterotrophic plate count, HPC) bacteria with 3. 93log and 2. 05log reductions, respectively. ClO2 was more effective than Cl2 at removing suspended HPC bacteria and similarly effective in biofilm bacterial removal. UV light alone was not effective in controlling suspended or biofilm bacteria compared to treatment with ClO2 or Cl2. Pre-treatment with UV was more effective overall for removal of HPC bacteria than treating with corresponding chemical disinfectants only; however, it did not lower required chemical dosages. Therefore, no significant differences were observed in DBP concentrations between ARs pre-treated with UV light and ARs not pre-treated. Disinfection with ClO2 produced fewer total trihalomethanes (TTHMs) and haloacetic acids (HAAs) than chlorination but did produce low levels of chlorite. These data indicate that replacing Cl2 with ClO2 would further control microbiological re-growth and minimize TTHM and HAA formation, but may introduce other DBPs. [Copyright &y& Elsevier]

Abstract: Objective: Up to now, observation of familial undescended testis (UDT) has been confined to the description of individual cases. The aim of our study was to evaluate the frequency of a positive family history and of associated urological anomalies in family members, and to calculate the risk of newborn male individuals having UDT if a family member is affected. Methods: A total of 374 patients who underwent surgery because of UDT and 374 controls without UDT were interviewed by means of a special questionnaire. We asked for a family history of UDT, as well as for other urogenital anomalies (varicocele, hydrocele, hypospadias, testicular cancer, renal anomalies). For statistical analysis the odds ratio was calculated. Results: Of the analysed patients, 85 (22.73%) had family members with UDT versus 7.5% of the control group. Of these 85 cases, brothers were involved in 37.3%, fathers in 35.2%, uncles in 23.5%, cousins in 16.5%, great-cousins in 8.2% and grandfathers in 7.1%. The risk of UDT in a newborn male is 3.6-fold overall, and 6.9-fold if a brother and 4.6-fold if the father is affected. The rate of family members with UDT and/or other urogenital anomalies in the patient group was nearly 2-fold higher than in the control group. Conclusions: Due to the increased familial risk and the higher percentage of a positive family history for UDT and other urogenital anomalies in patients with UDT, a genetic predisposition seems probable. [Copyright &y& Elsevier]

We present possible realizations of gauge inflation arising from a 5D N=1 supersymmetric U(1) model, where the extra dimension is compactified on a circle. A one-loop inflaton effective 4D potential is generated, with the inflaton being a ‘Wilson-line field’. It relies on a SUSY breaking. We first consider SUSY breaking to occur spontaneously within a ‘no-scale’ model by a non-zero F-term of the radion superfield which transmits SUSY breaking into the ‘visible’ sector. As an alternative, we study D-term SUSY breaking originating directly from the 5D gauge supermultiplet. Together with the usual KK resummation method, we present a calculation with the world-line formalism. The latter allows one to get the resulting effective potential directly as a sum over all winding modes. For both presented scenarios, the generated effective potentials have suitable forms for realizing successful inflation, i.e., are flat enough and give the needed number of e-foldings. In addition, there is a natural way to get strongly suppressed values for the potentials, which then could be associated with dark energy/quintessence. [Copyright &y& Elsevier]

Objectives: A new lithotriptor for intracorporeal lithotripsy was developed combining the two most effective lithotriptors. A combination of the mechanically driven Lithoclast Master and a new ultrasonic device was constructed. Efficacy was tested in standardized model stones and in patient treatment.Material: The new lithotriptor is composed of a Lithoclast Master and an ultrasonic device (EMS, Nyon, Switzerland). The 1.0 mm Lithoclast probe is advanced off-center through the hollow 3.3 mm ultrasonic probe and protrudes about 1 mm.Five different artificial stones of defined hardness and density were used as model stones for disintegration. Time until first fragmentation and complete fragmentation (particles smaller than 2.2 mm to fit through the ultrasonic probe), percent disintegration after 1 min and time until 50% disintegration were determined for the new device as well as lithoclast and ultrasound alone.A total of 68 patients were treated by percutaneous nephrolitholapaxy (PNL) with the new device from February 1999 to August 2001. Lithotripsy was performed after fluoroscopically guided puncture of the lower calix and dilatation of the nephrostomy tract with coaxial bougies. Thirty-five patients had complete and 33 patients partial staghorn calculi.Results: First fragmentation was reached 25–200 times faster with the combination as with either mode alone. Disintegrated stone mass after 1 min was 1.5–4 times larger in combined lithotripsy and 50% disintegration time 30–50% shorter.Clinically, complete stone free rate (KUB and ultrasound) was 66% after the first PNL. Sixteen out of 68 patients had a second look PNL with an overall stone free rate of 89.7% by dismission. Stone composition was calcium-oxalate–monohydrate in 13%, Ca-ox–monohydrate/uric acid in 35%, apatite in 20% and cystine in 11%.Conclusion: In in vitro experiments and clinically the new lithotriptor provides easy handling and high effectivity in fragmentation of all stones regardless of their composition. [ABSTRACT FROM AUTHOR]

An updated analysis of vector and axial-vector spectral functions is presented. The resonant contributions to the spectral integrals are shown to be expressible as multiples of 4π2fπ2, encoding the scale of spontaneous chiral symmetry breaking in QCD. Up to order T2 this behavior carries over to the case of finite temperature. [Copyright &y& Elsevier]

To retrospectively evaluate the performance of the commonly used ultrasound parameters of venous flow phasicity and Valsalva maneuver response for detecting iliocaval obstruction using venography as a gold standard. Lower extremity ultrasounds with a concurrent CT, MR, or conventional venography performed within 7 days, which served as ground truth for iliocaval obstructions, were further identified (n = 242 exams of 313 limbs). [Extracted from the article]