oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Search Results: 1 - 10 of 27 matches for " Karlson Hargroves "
All listed articles are free for downloading (OA Articles)
Page 1 /27
Display every page Item
The Trackless Tram: Is It the Transit and City Shaping Catalyst We Have Been Waiting for?  [PDF]
Peter Newman, Karlson Hargroves, Sebastian Davies-Slate, Daniel Conley, Marie Verschuer, Mike Mouritz, Dorji Yangka
Journal of Transportation Technologies (JTTs) , 2019, DOI: 10.4236/jtts.2019.91003
Abstract: Recent innovations in transport technology are now providing mobility that is cheaper, autonomous, electric, and with improved ride quality. While much of the world’s attention has been on how this can be applied to cars, there have been rapid adoption of these and other technologies in High Speed Rail and Metro Rail systems that run between and across cities. This paper shows how such innovations have now been applied to create the next generation of urban transit system called a Trackless Tram. Trackless Trams are effectively the same as traditional light rail except they run on rubber tyres avoiding disruption from construction for Light Rail, but they retain the electric propulsion (with batteries) and have high ride quality due to rail-type bogies, stabilization technologies and precision tracking from the autonomous optical guidance systems—with infrastructure costs reduced to as low as one tenth of a Light Rail system. As with Light Rail, a Trackless Tram System provides a rapid transit option that can harness the fixed route assurance necessary to unlock new land value appreciation that can be leveraged to contribute to construction and running costs whilst creating urban regeneration. The paper considers the niche for Trackless Trams in cities along with its potential for city shaping through the creation of urban re-development along corridors. The paper suggests that the adoption of Trackless Tram Systems is likely to grow rapidly as a genuine alternative to car and bus systems, supplementing and extending the niche occupied by Light Rail Transit (LRT). This appears to be feasible in any medium-sized or larger city, especially in emerging and developing economies, and case studies are outlined for Perth and Thimpu to illustrate its potential.
Corporate cartels and challenges to European labour market models Cárteles corporativos y desafíos de los modelos europeos del mercado de trabajo
Nils Karlson,Henrik Lindberg
Revista Internacional de Organizaciones , 2013,
Abstract: We propose that one of the main causes of shortcomings in European labour markets is the existence of corporate cartels, through which the state has delegated various forms of regulatory power to employers and employees that act as cartels. Analysis indicates that these cartel arrangements are not in the interest of labour because they are hard to combine with the demands of a modern and knowledge-based economy. Hence, a modernization of European labour market models is needed. Proponemos que una de las principales causas de las deficiencias que presentan los mercados de trabajo europeos es la existencia de cárteles corporativos, a través de los cuales el estado ha delegado varias maneras de regular el poder para empleados y empleadores que actúan como cárteles. El análisis indica que estos cárteles no actúan en interés del empleo ya que son difíciles de encajar con las demandas de una economía moderna basada en el conocimiento. Por tanto, una modernización de los modelos de mercado de trabajo Europeos se hace necesaria.
TNF-α Antagonist and Infection in Rheumatoid Arthritis  [PDF]
Julia F. Simard, Murray A. Mittleman, Nancy A. Shadick, Elizabeth W. Karlson
Open Journal of Rheumatology and Autoimmune Diseases (OJRA) , 2012, DOI: 10.4236/ojra.2012.22004
Abstract: Background: Anti-TNF treatment may increase infection risk, although this has been difficult to study because the timing of anti-TNF treatment is driven by disease activity, which may influence infection susceptibility leading to confounding that varies over time. We evaluated the association between anti-TNF initiation in rheumatoid arthritis (RA) patients on disease modifying anti-rheumatic drugs (DMARD) and infection using multiple approaches adjusting for time-varying confounding. Methods: 383 anti-TNF-na?ve RA patients on ≥ 1 non-biologic-DMARD at enrollment from the Brigham and Women’s Rheumatoid Arthritis Sequential Study (BRASS) were followed up to two years. Pooled logistic regressions estimated the association between anti-TNF and infection by including time-varying covariates in the adjusted models and inverse probability treatment weighting (IPTW). Results: Adjustment for time-varying disease activity and other suspected confounders yielded non-statistically significant positive associations between anti-TNF start and infection regardless of analytic approach (RRmvar_adj = 2.1, 95% CI: 0.8 - 5.8). Conclusions: Incorporating changing clinical status, and treatment indications and consequences, yielded consistently (though not significantly) elevated relative risks of infection associated with anti-TNF initiation. Due to limited statistical power, we cannot draw firm conclusions. However, we have illustrated multiple approaches adjusting for potential time-varying confounding in longitudinal studies and hope to replicate the approaches in larger studies.
Epstein–Barr virus and rheumatoid arthritis: is there a link?
Karen H Costenbader, Elizabeth W Karlson
Arthritis Research & Therapy , 2005, DOI: 10.1186/ar1893
Abstract: Rheumatoid arthritis (RA) is a chronic inflammatory polyarthritis that progressively destroys synovial joints and can cause systemic complications. RA affects about 1% of the world's population [1], and its prevalence in women is twofold to fourfold that in men [2,3]. RA has enormous personal, social, and economic impact [4,5]; women with RA have overall mortality rates 2.3-fold those in age-matched controls [6]. New biologic therapies, based on an increasing understanding of the molecular mechanisms involved in RA, afford a more normal life to many, but the burden of disease remains high. At present there is no known cure. Despite improved therapy, the long-term prognosis remains poor and average life expectancy is reduced by 3 to 18 years [7]. Both the direct costs of treatment of RA and the indirect costs of disability and loss from the workplace are high [8,9].RA is marked by extensive synovial hyperplasia and infiltration by lymphocytes, monocytes, macrophages, and fibroblasts. RA is a predominantly CD4+ T helper type 1 (Th1)-driven disease [10]. Aberrant T cell activation is one of the earliest events in the development of RA, with CD4+ T cells stimulating monocytes and macrophages to produce inflammatory cytokines, including interleukin (IL)-1, IL-6, and tumor necrosis factor-α (TNF-α), as well as proteolytic enzymes, destroying synovium, cartilage, and underlying bone [11]. The T cells infiltrating the rheumatoid synovium are oligoclonal, implicating an antigen-driven process [12,13], but the inciting antigen or antigens remain unidentified. Activated T cells also signal B cells to produce increased levels of immunoglobulins, including rheumatoid factor (RF). Autoreactive B cells also have a central role in the development of RA, producing autoantibodies that might be involved in tissue damage in RA [14].Genetic factors are important in disease susceptibility, but environmental exposures are probably crucial as well. Many exposures have been investigated as
Acute and Sub-Acute Toxicity of Ethanolic Leaf Extracts of Rumex abyssinica Jacq. (Polygonaceae) and Mentha spicata L. (Lamiaceae)  [PDF]
Maud Kamatenesi Mugisha, James Gakunga Ndukui, Agnes Namutembi, Paul Waako, Ann-Karl Borg Karlson, Patrick Vudriko
Pharmacology & Pharmacy (PP) , 2014, DOI: 10.4236/pp.2014.53038
Abstract:

Rumex abyssinica Jacq. (Polygonaceae) is locally used in management of allergies and female reproductive healthcare; whereas Mentha spicata L. (Lamiaceae) is used to treat gastrointestinal and respiratory distress, dandruff, halitosis and malaria in Uganda. Owing to the paucity of data on their safety profiles, this study evaluated the acute and sub-acute toxicities of 70% ethanolic leaf extracts of both plants in mice and Wistar albino rats. The oral acute toxicity of both plants was evaluated in Swiss mice of 7-8 weeks old (16-22 g) body weight and LD50 determined. Sub-acute toxicity was evaluated in Wistar albino rats (6 per group) at dose rates of 500, 1000 and 1500 mg/kg for 28 days. The LD50 of R. abyssinica and M. spicata in mice was 7727 mg/kg and 13,606 mg/kg body weight, respectively. General signs of toxicity due to large doses of both plants extract included hyperurination, abdominal muscle twitches and convulsions. In the sub-acute toxicity test, rats treated with both extracts did not exhibit any clinical signs

Late Complications following Endoscopic Sphincterotomy for Choledocholithiasis: A Swedish Population-Based Study
A. Langerth,L. Brandt,A. Ekbom,B.-M. Karlson
Diagnostic and Therapeutic Endoscopy , 2014, DOI: 10.1155/2014/745790
Abstract: In order to assess the risk of long-term complications following endoscopic sphincterotomy (ES) for common bile duct stones (CBDS), we conducted a cohort study. The study included 1,113 patients who underwent ES for CBDS in six different hospitals in central Sweden between 1977 and 1990. Through the use of the Swedish population registry, each patient was assigned five population-based controls matched for sex and age. Linkage to the Inpatient Registry yielded information on morbidity and mortality for the patients as well as for the controls. After one year of washout, there were 964 patients available for follow-up. The mean age was 70.6 years, 57% were women, and the mean length of follow-up was 8.9 years. The patients’ overall morbidity was significantly higher and we observed a tendency towards increased mortality as well. Recurrent CBDS was diagnosed in 4.1% of the patients. Acute cholangitis with a hazard ratio (HR) of 36 (95%CI 11–119.4) was associated with recurrent CBDS in 39% of the patients. HR for acute pancreatitis was 6.2 (95%CI 3.4–11.3) and only one patient had CBDS at the same time. In conclusion, we consider acute pancreatitis and cholangitis both as probable long-term complications after ES. 1. Introduction Long-term results after endoscopic sphincterotomy (ES) have been the topic of several studies, with a complication rate, including recurrent common bile duct stones (CBDS), between 5 and 24%. Most authors, however, report frequencies around 10% [1–5]. There is currently no agreed definition of a late complication, though, and various publications differ greatly. As the summary in Table 1 shows, the rate of recurrent CBDS varies between 3.5 and 14% [1–11]. Keizman et al. [12] demonstrated recurrent CBDS in the elderly (older than 79) and in younger patients (less than 51 years old) of 20% and 4%, respectively. The largest study so far of 7,?585 patients by Seifert et al. in 1982 [13] found recurrent stones in about 5.8%, but the follow-up time was not reported. Some of the studies include reports of acute cholangitis together with CBDS, but it was not until 1996 that Prat et al. [7] described “sine materia cholangitis.” The mean follow-up was 9.6 years and three out of 154 patients (1.9%) developed acute cholangitis without recurrent CBDS. In a more recent study by Costamagna et al. [4], with 458 patients and a mean follow-up of 6.8 years, four of the 458 patients (0.9%) had a diagnosis “sine materia cholangitis.” In contrast, some authors report no cases of acute cholangitis without concurrent CBDS [1, 2, 9]. Few publications have
Activated Human T Cells Secrete Exosomes That Participate in IL-2 Mediated Immune Response Signaling
Jessica Wahlgren, Tanya De L. Karlson, Pernilla Glader, Esbj?rn Telemo, Hadi Valadi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0049723
Abstract: It has previously been shown that nano-meter sized vesicles (30–100 nm), exosomes, secreted by antigen presenting cells can induce T cell responses thus showing the potential of exosomes to be used as immunological tools. Additionally, activated CD3+ T cells can secrete exosomes that have the ability to modulate different immunological responses. Here, we investigated what effects exosomes originating from activated CD3+ T cells have on resting CD3+ T cells by studying T cell proliferation, cytokine production and by performing T cell and exosome phenotype characterization. Human exosomes were generated in vitro following CD3+ T cell stimulation with anti-CD28, anti-CD3 and IL-2. Our results show that exosomes purified from stimulated CD3+ T cells together with IL-2 were able to generate proliferation in autologous resting CD3+ T cells. The CD3+ T cells stimulated with exosomes together with IL-2 had a higher proportion of CD8+ T cells and had a different cytokine profile compared to controls. These results indicate that activated CD3+ T cells communicate with resting autologous T cells via exosomes.
Genetic polymorphisms in PTPN22, PADI-4, and CTLA-4 and risk for rheumatoid arthritis in two longitudinal cohort studies: evidence of gene-environment interactions with heavy cigarette smoking
Karen H Costenbader, Shun-Chiao Chang, Immaculata De Vivo, Robert Plenge, Elizabeth W Karlson
Arthritis Research & Therapy , 2008, DOI: 10.1186/ar2421
Abstract: We studied RA risk associated with PTPN22 (rs2476601), PADI-4 (rs2240340), and CTLA-4 (rs3087243) in the Nurses' Health Study (NHS) and NHSII. Participants in NHS were aged 30 to 55 years at entry in 1976; those in NHSII were aged 25 to 42 years at entry in 1989. We confirmed incident RA cases through to 2002 in NHS and to 2003 in NHSII by questionnaire and medical record review. We excluded reports not confirmed as RA. In a nested case-control design involving participants for whom there were samples for genetic analyses (45% of NHS and 25% of NHSII), each incident RA case was matched to a participant without RA by year of birth, menopausal status, and postmenopausal hormone use. Genotyping was performed using Taqman single nucleotide polymorphism allelic discrimination on the ABI 7900 HT (Applied Biosystems, 850 Lincoln Centre Drive, Foster City, CA 94404 USA) with published primers. Human leukocyte antigen shared epitope (HLA-SE) genotyping was performed at high resolution. We employed conditional logistic regression analyses, adjusting for smoking and reproductive factors. We tested for additive and multiplicative interactions between each genotype and smoking.A total of 437 incident RA cases were matched to healthy female control individuals. Mean (± standard deviation) age at RA diagnosis was 55 (± 10), 57% of RA cases were rheumatoid factor (RF) positive, and 31% had radiographic erosions at diagnosis. PTPN22 was associated with increased RA risk (pooled odds ratio in multivariable dominant model = 1.46, 95% confidence interval [CI] = 1.02 to 2.08). The risk was stronger for RF-positive than for RF-negative RA. A significant multiplicative interaction between PTPN22 and smoking for more than 10 pack-years was observed (P = 0.04). CTLA-4 and PADI-4 genotypes were not associated with RA risk in the pooled results (pooled odds ratios in multivariable dominant models: 1.27 [95% CI = 0.88 to 1.84] for CTLA-4 and 1.04 [95% CI = 0.77 to 1.40] for PADI-4). No gene-ge
Protein, iron, and meat consumption and risk for rheumatoid arthritis: a prospective cohort study
Elizabeth Benito-Garcia, Diane Feskanich, Frank B Hu, Lisa A Mandl, Elizabeth W Karlson
Arthritis Research & Therapy , 2007, DOI: 10.1186/ar2123
Abstract: Rheumatoid arthritis (RA) is associated with both genetic and environmental factors [1-7], but studies of dietary risk factors have been inconclusive [8]. Studies of diet and risk for RA offer the potential to identify modifiable factors and so prevent RA in high-risk patients; they may also provide insights into disease pathogenesis.Buchanan and Laurent [9] implicated diets high in protein in the etiology of RA. Furthermore, low-protein diets may improve RA symptoms [10-13]. In ecologic studies, the prevalence of RA is higher in countries with greater consumption of red meat [14]. More recently, Pattison and colleagues [15] reported the first prospective investigation of red meat and risk for inflammatory polyarthritis (IP) and concluded that higher intakes of both red meat and protein increased the risk for IP, whereas iron – another nutrient component of meat – exhibited no association. The authors acknowledged that it remained unclear whether the observed associations were causative or whether meat consumption was a marker for other lifestyle factors.To examine this issue further, we prospectively assessed risk for RA in relation to intakes of protein, iron, and meat in women in the Nurses' Health Study (NHS). We examined these intakes with further classifications into animal and vegetable protein; dietary, supplemental, and heme iron; and red meat, poultry, and fish.The NHS was established in 1976 when 121,700 female registered nurses (98% white), aged 30–55 years and residing in one of 11 US states, completed and returned the initial NHS mailed questionnaire on their medical history and lifestyle. Every 2 years, follow-up questionnaires have been sent to obtain up-to-date information on risk factors and to identify newly diagnosed diseases. Deaths are reported by family members or by the postal service in response to the follow-up questionnaires. In addition, we use the National Death Index to search for nonrespondents who might have died in the preceding inte
Sleep and recovery in physicians on night call: a longitudinal field study
Birgitta Malmberg, G?ran Kecklund, Bj?rn Karlson, Roger Persson, Per Flisberg, Palle ?rbaek
BMC Health Services Research , 2010, DOI: 10.1186/1472-6963-10-239
Abstract: Sleep, monitored by actigraphy and Karolinska Sleep Diary/Sleepiness Scale on one night after daytime work, one night call, the following first and second nights post-call, and a Saturday night, was compared between 15 anaesthesiologists and 17 paediatricians and ear, nose, and throat surgeons.Recovery patterns over the days after night call did not differ between groups, but between days. Mean night sleep for all physicians was 3 hours when on call, 7 h both nights post-call and Saturday, and 6 h after daytime work (p < 0.001). Scores for mental fatigue and feeling well rested were poorer post-call, but returned to Sunday morning levels after two nights' sleep.Despite considerable sleep loss during work on night call, and unexpectedly short sleep after ordinary day work, the physicians' self-reports indicate full recovery after two nights' sleep. We conclude that these 16-hour night duties were compatible with a short-term recovery in both physician groups, but the limited sleep duration in general still implies a long-term health concern. These results may contribute to the establishment of safe working hours for night-call duty in physicians and other health-care workers.Studies of physicians have shown that night-call duty with long work hours, restricted sleep, stress, time pressure, and high demands may cause impaired performance and adverse effects on subjective health [1-4]. Working schedules involving long working hours also seem to have a negative influence on caregivers' decision-making capabilities, which may have a profound impact on patients' safety [5,6]. Although sleep is crucial to recovery and survival, there is limited knowledge about the effects of night-call duty on sleep duration, sleep quality, and recovery time. One might assume effects similar to those from classic rotating shift work, but the irregular character of night-call schedules and the longer shifts make comparison difficult. In a study from 1990, ?kerstedt and co-workers monitored
Page 1 /27
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.