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This study investigates impact of beam pipe material and external magnetic field on electron cloud build up mechanism. The machine parameters are in the scope of CLIC damping rings. Two dierent filling schemes for 0.5 and 1 ns bunch spacings are considered. VSim Plasma Discharges and Plasma Acceleration package is employed to perform 2D electrostatic particle in cell simulations such that the space charge eect and Furman-Pivi secondary emission yield model are included in the computations. It is illustrated that the build up time varies due to bunch spacing while the external magnetic field influences the number of electrons generated by initial seeds. The evolution of generated secondary electrons due to bunch passes and the corresponding energy levels are presented in details., CERN Yellow Reports: Conference Proceedings, Vol. 9 (2020): Proceedings of the ICFA mini-Workshop on Mitigation of Coherent Beam Instabilities in Particle Accelerators, Zermatt, Switzerland, 23–27 September 2019

In an effort to cope with increasing passenger demand on its network, Transport for London (TfL) implemented in the second half of 2017 an experiment on one of its busiest metro train platforms. The platform surface was painted to highlight the exact location of the train doors once it comes to a full stop and to direct passengers to wait in parts of the platform that would not obstruct passengers from alighting from the train and leaving the platform. We estimate the effect of this intervention to change passenger behaviour on the platform on train waiting and delay times. We use different sets of assumptions about what the counterfactual change in waiting and delay times would have been in the absence of the intervention. Depending on the assumptions, we find that the intervention has reduced train waiting times between 0 and 6.6%. We also find that this reduction came about mainly through reducing delay times of trains once they are delayed which were cut by between 4.6% and 12.6%. The reductions are not evenly distributed throughout the day, but tend to occur during peak traffic hours. The value of the implied time savings per year are £156,000 at a cost of £25,000, amounting to a return of £6 per £1 investment. If the dwell time reduction could increase train frequency on the affected line by 1 train per hour, however, then TfL could save another £3.6 million.

We use an annual household panel to test which features of prospect theory can be supported by measures of life satisfaction. We also test whether recalled or expected life satisfaction is anchored at current life satisfaction and adjusted in the direction of the recall or expectation. Using a fixed effects estimator we find that life satisfaction contains features of both classic expected utility and prospect theory. Life satisfaction depends positively on levels of income, good health, and on employment. It also depends positively on income and employment improvements, however the reverse is true for health increases. Life satisfaction is concave in income gains and convex in income losses, and it exhibits loss aversion in income and employment status, but not in health. Moreover, we find that current levels of life satisfaction are better predictors of recalled (expected) life satisfaction than past (future) life satisfaction. The results support viewing life satisfaction as representing a mixture of the classic decision utility of expected utility theory, and the value function of prospect theory. Subjects seem to use an anchoring and adjustment heuristic when answering questions about past and expected life satisfaction.

We analyse the effect of credit supply on households' homeownership status and mortgage debt, as well as other variables relating to housing costs and home equity. We demonstrate that banking deregulation as enacted by the Interstate Banking and Branching Efficiency Act (IBBEA) together with states' autonomy to set the degree and timing of deregulation provides an exogenous shift in credit supply which shows variation across states and time. We use this variation to isolate the effect of credit supply from confounding factors which could simultaneously affect credit supply and demand. Using a rich individual-level panel covering the period 1996 to 2008, and controlling for individual and region-year fixed effects, we find that a shift from full regulation to full deregulation increases the probability of owning a home by one, and of having a mortgage by two percentage points. The deregulation observed between 1990 and 2005 can explain at least one fifth, and up to 45% of the increase in homeowneship and the share of households with mortgages. For observations residing in non-metropolitan areas, we also find significant effects of deregulation on the amount of mortgage debt, reported home values, monthly mortgage payments, and debt to value as well as debt to income ratios. Most of these effects are driven by young households, and by individuals with higher incomes. Our results inform on the causes of the rise in homeownership and mortgage debt in the 1990s and 2000s which have led up to the housing crisis in the late 2000s.

Objective: Laparoscopic cholecystectomy is a minimally invasive surgical procedure but it is still associated with postoperative pain within the first 24 hours. Ultrasound-guided transversus abdominis plane block is a regional anesthetic technique which provides postoperative analgesia in abdominal surgery. We aimed to determine the effects of the TAP block on discharge time, non-opioid and opioid consumption, shoulder tip pain, incidence of postoperative nausea and vomiting, and severity of pain evaluated with visual analogue scale in patients who underwent laparoscopic cholecystectomy. Methods: Seventy-two eligible patients who underwent laparoscopic cholecystectomy were included in the study. In 38 patients ultrasound-guided TAP block was performed, and 34 patients were treated with conventional methods such as non-steroid anti-inflamatory drugs. Data related to VAS pain scores, shoulder tip pain, intraoperative opioid consumption, postoperative non-opioid and opioid consumption, nausea vomiting and discharge time were collected retrospectively to determine statistically significant differences between TAP block and non-TAP block groups. Results: VAS pain scores were globally reduced at all time periods in two groups (significant group main effect, F(7.760)=94.47, P

A prospective community study in a highly malaria endemic area of Papua New Guinea found that infection with multiple Plasmodium falciparum genotypes was an indicator of lowered risk of subsequent clinical attack. The results suggest that concurrent or very recent infections provide protection from superinfecting parasites. The finding of an association between reduced risk of clinical malaria and infection with parasites of merozoite surface protein 1 (MSP-1) type RO33 or MSP-2 type 3D7 further suggests that the concomitant immunity is, at least in part, a consequence of a response to these major merozoite surface proteins

The aim of this prospective randomized, double-blind study was to investigate the effects of pressure controlled and volume controlled ventilation on mucociliary clearance under general anaesthesia maintained with total intravenous anaesthesia. After approval by the Ethics Committee, 60 patients scheduled for tympanoplasty or tympanomasteidectomy under general anaesthesia were enrolled in the study. In Group I (n=30), the lungs of the patients were ventilated using volume-controlled mode with 8 ml/kg tidal volume. In Group II (n=30) pressure controlled ventilation mode was used with 10 cm H2O pressure support. Mucociliary clearance was assessed by in vivo saccharine transit time in preoperative and postoperative periods. The groups showed no significant differences regarding age, height, body mass index, peak and plateau airway pressures. Saccharine transit time values did not differ significantly between the groups. In conclusion, volume-controlled and pressure-controlled ventilation modes have no significant impact on nasal saccharine transit time. © 2017, Scientific Publishers of India. All rights reserved.

The complexity and tight integration of electromechanical systems often makes them "brittle" and hard to modify in response to changing requirements. We aim to remedy this by capturing expert knowledge as functional blueprints, an idea inspired by regulatory processes that occur in natural morphogenesis. We then apply this knowledge in an intelligent design variation tool. When a user modifies a design, our tool uses functional blueprints to modify other components in response, thereby maintaining integration and reducing the need for costly search or constraint solving. In this paper, we refine the functional blueprint concept and discuss practical issues in applying it to electromechanical systems. We then validate our approach with a case study applying our prototype tool to create variants of a miniDroid robot and by empirical evaluation of convergence dynamics of networks of functional blueprints.

Introduction: Increase in visceral adipose tissue (VAT) is associated with cardiovascular risk. However, the relationship between atherosclerosis and VAT has not yet been adequately studied in chronic kidney disease (CKD). The aim of this study was to assess the relationship among VAT, adipokines, and atherosclerosis in patients with CKD. Materials and methods: 45 healthy control, 53 predialysis patients, and 52 hemodialysis patients have been enrolled in the study. Intima media thickness (IMT) of the carotid artery, and VAT measurements were evaluated via ultrasonography. Results: IMT (p:0.002), VAT (p:0.021), adiponectin (p

Introduction: Increase in visceral adipose tissue (VAT) is associated with cardiovascular risk. However, the relationship between atherosclerosis and VAT has not yet been adequately studied in chronic kidney disease (CKD). The aim of this study was to assess the relationship among VAT, adipokines, and atherosclerosis in patients with CKD.Materials and methods: 45 healthy control, 53 predialysis patients, and 52 hemodialysis patients have been enrolled in the study. Intima media thickness (IMT) of the carotid artery, and VAT measurements were evaluated via ultrasonography.Results: IMT (p:0.002), VAT (p:0.021), adiponectin (plt;0.001) and pentraxin-3 (p:0.003) were higher in predialysis patients than healthy controls. The values of IMT (plt;0.001), VAT (p:0.0014), adiponectin (p:0.005), pentraxin-3 (p: lt;0.001), C reactive protein (CRP) (p:0.009), triglyceride (p: lt;0.001) and parathyroid hormone (PTH) (plt;0.001), were higher in hemodialysis patients than healthy controls. VAT was positively correlated with CRP(r: 0, 23 p: 0.005), IMT (r: 0.347 plt;0.001), body mass index (BMI) (r: 0.33 plt;0.001), and negatively correlated with creatinine clearance (R: -0.245 p: 0.003). VAT is independently related with adiponectin (ß:-0.213 p: 0.008), BMI (ß: 0.369, Plt;0.001), and CRP (ß:0.164, P:0.032) in multiple regression analysis. IMT was positively correlated with VAT (r: 0.347 plt;0.001), CRP (r: 0.186 p: 0.022), age (r: 0.333 plt;0.001), BMI (r: 0.444 plt;0.001) in all participants.Conclusion: These findings show that VAT is a strong risk factor for atherosclerosis in patients with CKD. However IMT was not correlated with adiponectin, pentraxin-3, and leptin in patients with CKD. Also sonographic measurement of VAT could be useful to stratify the risk of cardiovascular disease in patients with CKD.

Structural estimation of labor adjustment costs suffers from a myriad of specification errors, largely due to data constraints. The literature usually assumes that adjustment decisions are made at the firm level, that adjustment happens at the frequency at which a firm is observed (typically annually or quarterly), and that adjustment costs are incurred on net changes in employment. This paper builds and estimates a dynamic optimization model of labor adjustment of establishments using data that permit 1) specifying any desired adjustment frequency (including daily adjustment), 2) using the micro unit of an establishment, 3) estimating the model based on net and on gross employment flows and 4) allowing for simultaneous hirings and separations. Results for adjustment costs depend crucially on the model specification. Only a monthly adjustment model yields positive cost parameters, while estimates from quarterly and annual adjustment models imply negative adjustment costs (that is adjustment implies a gain rather than a loss). Estimating the model on net employment changes imply hiring and separation costs of more than four annual median salaries, while the model on gross changes implies costs on the order of two annual median salaries. Adjustment costs differ significantly between small and large establishments. However, a static specification of the model performs equally well as the dynamic model with respect to out-of-sample predictions.

We examine the effects of homeownership on individuals' unemployment durations in the USA. We take into account that an unemployment spell can terminate with a job or with a non-participation transition. The endogeneity of homeownership is addressed through the estimation of a full maximum likelihood function which jointly models the competing hazards and the probability of being a homeowner. Unobserved factors contributing to the probability of being a homeowner are allowed to be correlated with unobservable heterogeneity in the hazard rates. We find that unemployed homeowners are less likely to find a job than renters. The effect is small but statistically significant for most specifications. The effect is stronger for outright owners and weaker for mortgage holders. We also find that outright owners have a higher and mortgage holders a lower probability of exiting to non-participation than renters.

It is widely debated whether immigrants who live among co-ethnics are less willing to integrate into the host society. Exploiting the quasi-experimental guest worker placement across German regions during the 1960/70s as well as information on immigrants' inter-ethnic contact networks and social activities, we are able to identify the causal effect of ethnic concentration on social integration. The exogenous placement of immigrants ‘switches off’ observable and unobservable differences in the willingness or ability to integrate which have confounded previous studies. Evidence suggests that the presence of co-ethnics increases migrants' interaction cost with natives and thus reduces the likelihood of integration.

PubMedID: 23189295 Purpose: It is unknown whether zoledronic acid (ZA) interferes with initial bone healing at implant sites. The goal of this study was to examine the effects of systemic zoledronic acid administration on osseintegration of hydroxyapatite (HA)-coated and resorbable blast material surface (RBM) implants in rabbit models. Materials and Methods: Twenty-eight male New Zealand rabbits (aged 6 to 12 months) were used in this study. Rabbits were randomly assigned to four groups. In group A, HA-coated implants were placed in the right tibia of seven rabbits. In group B, RBM-surface implants were placed in the right tibia of seven rabbits. In group C, HA-coated implants were placed in seven rabbits with intravenous (IV) administration of ZA. Finally, in group D, RBM-surface implants were placed in seven rabbits with IV administration of ZA. For groups C and D, IV zoledronic acid (0.1 mg/kg) was performed monthly during the entire osseointegration period. All of the rabbits were sacrificed 12 weeks after the implantation, and tibial specimens were harvested. Histomorphometric boneto- implant contact (BIC) analysis and the data were statistically analyzed. Results: The highest BIC percentage was detected in group D, with a mean value of 56.73% ± 1.85%, as compared with 45.80% ± 3.77% in group C, 35.11% ± 0.76% in group B, and 31.14% ± 1.04% in group A. Conclusions: Histomorphometric analyses showed significant improvement in the osseointegration of implants in the RBM-surface ZA group compared with the HA-coated ZA group. The results of this study suggest that systemic ZA administration may improve osseointegration of titanium implants in bone. © 2012 by Quintessence Publishing Co Inc.

The desirability function (DF) is widely used in multiobjective optimization problems especially when individual design objectives have conflicting responses. DF successfully transforms a complicated problem into a classical single parameter optimization problem by combining contradicting constraints. It can be applied to complex high-dimensional and multimodal problems where classical iterative methods are often insufficient to provide practical solutions. DF, however, requires prior knowledge about the trade-off parameter ranges and the preference parameters, namely, the target bound and shape. Thus, expert knowledge before optimization is often critical for convergence. In this work, multiobjective optimization problem is illustrated on thinned array antenna design. Single and two objective optimizations are compared with the all-active (no thinning) array. Adaptive desired function (ADF) is proposed, which requires no prior knowledge about the trade-off objectives. ADF is observed to provide faster convergence and better optimization results/behavior with its "fire, monitor, and update" approach when compared with the classical DF's "fire, forget, and if it does not converge then restart" approach.

I analyze the role of regional ethnic capital – defined as the average years of schooling of ethnic groups – in the educational attainment of young second generation immigrants in Germany and whether results are sensitive to regional aggregation. I find evidence for externalities of ethnic capital for ethnic groups at the regional level. A higher average education of ethnics makes attendance of higher-quality secondary schools more likely. Moreover, the marginal effect of the externality is increasing in the ethnic concentration in the region. However, if higher than regional aggregates are used for the measurement of ethnic capital, no externalities are detected.

Studies that investigate the effect of the regional ethnic composition on immigrant outcomes have been complicated by the self-selection of ethnic minorities into specific neighbourhoods. We analyse the impact of own-ethnic concentration on the language proficiency of immigrants by exploiting the fact that the initial placement of guest-workers after WWII was determined by labour demanding firms and the federal labour administration and hence exogenous to immigrant workers. Combining several data sets, we find a small but robust and significant negative effect of ethnic concentration on immigrants’ language ability. Simulation results of a choice model in which location and learning decisions are taken simultaneously confirm the presence of the effect. Immigrants with high learning costs are inclined to move to ethnic enclaves, so that the share of German-speakers would increase only modestly even under the counterfactual scenario of a regionally equal distribution of immigrants across Germany.

I estimate the costs for establishments of hires and separations using a dynamic labor demand framework and matched employer-employee data from Germany, which records the exact dates of start and end of an employment spell. I estimate adjustment costs under different assumptions of adjustment frequencies. Under the assumption that establishments revise their labor demand every month, GMM estimates suggest hiring costs per employee of approximately 5,000 Euros, and costs of separations of 1,000 Euros. Hiring costs vary considerably between skilled (8,000 to 28,000 Euros per hire) and unskilled (4,000 to 8,000 Euros) labor. Spatial aggregation (large establishments) is associated with lower cost estimates, and only monthly adjustment frequencies yield estimates consistent with theoretical predictions.