Singapore's public and private transport modes : an economic comparison and policy implications

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.Includes bibliographical references (p. 129-133).Frequently, public decisions on transportation are based on cost benefit analyses that do not take into account the costs that private individuals are eventually led to spend in order to use these systems, even though these expenditures are sizeable. For FY2006-2007 in Singapore, we estimate that more than 90% of the S$34.4 billion to S$34.9 billion spent on the private automobile system were borne by private individuals. In contrast, only about 65% of the S$1.66 billion spent on the public transport system were borne by private individuals. The inclusion of private expenditures shows that the private automobile transport system costs society at least 20.7 times as much as the public transport system, even though 64$2.05 per passenger-kilometer, or 14 times as much as public transport trips, which cost S$0.143 per passenger-km. Applying derived economic and time cost functions to each trip from the 2004 home travel survey data, we compared trips made among each of the 82 postal sectors of Singapore, and found that the economic costs to society for private car driver trips far exceed those made with public transport for all of the 1,906 postal sector combinations analyzed. Although the time costs for private car driver trips were substantially lower than those of public transport trips for almost all of the origin-destination pairs, these were not sufficient to offset the far higher economic costs to society. We have highlighted particular zonal combinations for which differences in economic, time, and total costs between private car driver trips and public transport trips were very pronounced, as these promise the largest potential benefits to society if the differences between public and private modes were bridged.(cont.) Therefore policies should be pursued to increase the share of variable automobile costs as a percentage of total costs. In parallel, other policy measures should include improvements of Rapid Transit System coverage specially along the corridors identified in this thesis, increases in road pricing, and actions to shift the burden of parking costs to private motorists.by Chin Ning Ho.S.M

Investigation of the Surface Resistance of Niobium Between 325 MHz and 1300 MHz Using a Coaxial Half-wave Cavity

The Center for Accelerator Science at Old Dominion University has built a half-wave coaxial cavity (*) to measure the surface resistance of niobium as a function of frequency, temperature, rf field, preparation techniques, over a wide range of frequencies of interest for particle accelerators. The characteristics of the half-wave coaxial cavity provide these information on a same surface. The preliminary results showed clearly the frequency dependence of residual surface resistance (**). After establishing baseline, we have conducted a study of low temperature baking effect on the surface resistance under controlled environment. This paper will describe the details of the test procedure, results and we will explore underlying physics of the phenomenon. * H. Park et al., MOPB003, Proc. SRF2015, http://jacow.org/** H. Park et al., THPB080, Proc. SRF2017, http://jacow.org

Cryogenic Test Results of the SPS Prototype RF-Dipole Crabbing Cavity With Higher Order Mode Couplers

The rf-dipole crabbing cavity planned for the LHC High Luminosity Upgrade is designed to deliver a transverse kick of 3.34 MV; crabbing the proton beam in the horizontal plane. The proton beams of the LHC machine operating at 7 TeV each sets high impedance thresholds on the crabbing cavity systems. The rf-dipole crabbing cavity is designed with a two higher order mode couplers to suppress those HOMs. The first prototype of the HOM couplers are fabricated at Jefferson Lab. This paper reports the cryogenic test results of the HOM couplers with the SPS prototype rf-dipole cavity

A Novel Tetrameric PilZ Domain Structure from Xanthomonads

PilZ domain is one of the key receptors for the newly discovered secondary messenger molecule cyclic di-GMP (c-di-GMP). To date, several monomeric PilZ domain proteins have been identified. Some exhibit strong c-di-GMP binding activity, while others have barely detectable c-di-GMP binding activity and require an accessory protein such as FimX to indirectly respond to the c-di-GMP signal. We now report a novel tetrameric PilZ domain structure of XCC6012 from the plant pathogen Xanthomonas campestris pv. campestris (Xcc). It is one of the four PilZ domain proteins essential for Xcc pathogenicity. Although the monomer adopts a structure similar to those of the PilZ domains with very weak c-di-GMP binding activity, it is nevertheless interrupted in the middle by two extra long helices. Four XCC6012 proteins are thus self-assembled into a tetramer via the extra heptad repeat α3 helices to form a parallel four-stranded coiled-coil, which is further enclosed by two sets of inclined α2 and α4 helices. We further generated a series of XCC6012 variants and measured the unfolding temperatures and oligomeric states in order to investigate the nature of this novel tetramer. Discovery of this new PilZ domain architecture increases the complexity of c-di-GMP-mediated regulation

A network meta-analysis of 12,116 individuals from randomized controlled trials in the treatment of depression after acute coronary syndrome

Background: Post-acute coronary syndrome (ACS) depression is a common but not well understood complication experienced by ACS patients. Research on the effectiveness of various therapies remains limited. Hence, we sought to conduct a network meta-analysis to assess the efficacy of different interventions for post-ACS depression in improving patient outcomes. Methods and findings: Three electronic databases were searched for randomised controlled trials describing different depression treatment modalities in post-ACS patients. Each article was screened based on inclusion criteria and relevant data were extracted. A bivariate analysis and a network meta-analysis was performed using risk ratios (RR) and standardized mean differences (SMD) for binary and continuous outcomes, respectively. A total of 30 articles were included in our analysis. Compared to standard care, psychosocial therapy was associated with the greatest reduction in depression scores (SMD:-1.21, 95% CI: -1.81 to -0.61, p<0.001), followed by cognitive behavioural therapy (CBT) (SMD: -0.75, 95% CI: -0.99 to -0.52, p<0.001), antidepressants (SMD: -0.73, 95% CI: -1.14 to -0.31, p<0.001), and lastly, combination therapy (SMD: -0.15, 95% CI: -0.28 to -0.03, p = 0.016). No treatment modalities was found to be more effective in reducing depression scores when compared to one another. Additional analysis showed that these treatment modalities did not have significant impact on the overall mortality, cardiac mortality and recurrent myocardial infarction. Conclusion: This network meta-analysis found that the treatment effect of the various psychological modalities on depression severity were similar. Future trials on psychological interventions assessing clinical outcomes and improvement in adherence to ACS-specific interventions are needed

A qualitative systematic review of anonymous/unspecified living kidney and liver donors’ perspectives

Objectives & background: Anonymous live organ donors or unspecified donors are individuals willing to be organ donors for any transplant recipient with whom they have no biological or antecedent emotional relationship. Despite excellent recipient outcomes and the potential to help address organ scarcity, controversy surrounds the unconditional act of gifting one’s organs to an unrelated recipient. This qualitative systematic review provides insights into the first-hand experiences, motivations, and challenges that unspecified donors face. Methods: A systematic search was conducted on Medline, Embase, CINAHL, PsycINFO, and Web of Science database for qualitative literature regarding unspecified living donors’ motivations and experiences in liver and kidney transplantation. An inductive thematic analysis was conducted to generate themes and supportive subthemes. Results: 12 studies were included. The four major themes were (i) motivations, (ii) perception of risks, (iii) donor support, and (iv) benefits of donation. Unspecified donors demonstrated a deep sense of social responsibility but tended to underestimate health risks in favour of benefits for recipients. Despite the lack of emotional support from family and friends, the decision to donate was a resolute personal decision for donors. Majority benefitted emotionally and did not express regret. Conclusion: This qualitative review bridges the gap in literature on unspecified living donor psychology and provides a comprehensive understanding of the decision-making matrix and experiences of donors

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Phenomic analysis of chronic granulomatous disease reveals more severe integumentary infections in X-Linked compared with autosomal recessive chronic granulomatous disease

BACKGROUND : Chronic granulomatous disease (CGD) is an inborn error of immunity (IEI), characterised by recurrent bacterial and fungal infections. It is inherited either in an Xlinked (XL) or autosomal recessive (AR) mode. Phenome refers to the entire set of phenotypes expressed, and its study allows us to generate new knowledge of the disease. The objective of the study is to reveal the phenomic differences between XL and AR-CGD by using Human Phenotype Ontology (HPO) terms. METHODS : We collected data on 117 patients with genetically diagnosed CGD from Asia and Africa referred to the Asian Primary Immunodeficiency Network (APID network). Only 90 patients with sufficient clinical information were included for phenomic analysis. We used HPO terms to describe all phenotypes manifested in the patients. RESULTS : XL-CGD patients had a lower age of onset, referral, clinical diagnosis, and genetic diagnosis compared with AR-CGD patients. The integument and central nervous system were more frequently affected in XL-CGD patients. Regarding HPO terms, perianal abscess, cutaneous abscess, and elevated hepatic transaminase were correlated with XL-CGD. A higher percentage of XL-CGD patients presented with BCGitis/BCGosis as their first manifestation. Among our CGD patients, lung was the most frequently infected organ, with gastrointestinal system and skin ranking second and third, respectively. Aspergillus species, Mycobacterium bovis, and Mycobacteirum tuberculosis were the most frequent pathogens to be found. CONCLUSION : Phenomic analysis confirmed that XL-CGD patients have more recurrent and aggressive infections compared with AR-CGD patients. Various phenotypic differences listed out can be used as clinical handles to distinguish XL or AR-CGD based on clinical features.The Society for Relief of Disabled Children and Jeffrey Modell Foundation.https://www.frontiersin.org/journals/immunologydm2022Paediatrics and Child Healt

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data