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Humans are greatly modifying biogeochemical cycles, in part, by increasing the abundance of many trace elements in heavily developed environments. As a means to study the biogeochemical cycling of trace elements in the urban landscape, we examined their accumulation in the sediments of ponds located in residential developments. To do so, we measured the content of trace elements (Ti, V, Cr, Co, Ni, Cu, Zn, Mo, Ag, Cd, Ba, Tl, Pb) and minerals (Na, Mg, Al, K, Ca, Mn, Fe) in the sediments of stormwater management ponds located in residential catchments of southern Ontario, Canada. Trace elements and associated mineral composition of the sediments primarily clustered in three groups. In one group, several trace elements (e.g., Co and V) were correlated to soil-related minerals (Al and Fe), which indicate a predominant role of soil erosion in their movement across the urban landscape. Elements in the second group (Cd, Pb, Cu, Zn, and Mo) were positively correlated with sediment organic carbon content suggesting an importance of internal pond processing such as adsorption to organic matter. In the third group, Ca and Ag negatively correlated with most other elements likely because, at least for Ca, importation of carbonates in coarse particulate material (i.e., sand) dilutes the concentration of other trace elements. Variability in trace elements among ponds and between municipalities suggests that these elements are deposited and move differently among catchments in a relatively homogenous urban landscape. Our results demonstrate a trace element biogeochemistry in urban environments that is connected to human sources, physical disturbance of the landscape, biological processing, and underlying geological composition of the catchment. [ABSTRACT FROM AUTHOR]

Background Urinary stone disease is common, with an estimated prevalence among the general population of 2% to 3%. Ureteric stones can cause severe pain and have a significant impact on quality of life, accounting for over 15,000 hospital admissions in England annually. Uncomplicated cases of smaller stones in the lower ureter are traditionally treated expectantly. Those who fail standard care or develop complications undergo active treatment, such as extracorporeal shock wave lithotripsy or ureteroscopy with stone retrieval. Such interventions are expensive, require urological expertise and carry a risk of complications. Growing understanding of ureteric function and pathophysiology has led to the hypothesis that drugs causing relaxation of ureteric smooth muscle, such as the selective α-blocker tamsulosin and the calcium-channel blocker nifedipine, can enhance the spontaneous passage of ureteric stones. The use of drugs in augmenting stone passage, reducing the morbidity and costs associated with ureteric stone disease, is promising. However, the majority of clinical trials conducted to date have been small, poor to moderate quality and lacking in comprehensive economic evaluation. This trial aims to determine the clinical and cost-effectiveness of tamsulosin and nifedipine in the management of symptomatic urinary stones. Methods/design The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial is a multicentre, double-blind, randomized controlled trial evaluating two medical expulsive therapy strategies (nifedipine or tamsulosin) versus placebo. Patients aged 18 to 65 with a ureteric stone confirmed by non-contrast computed tomography of the kidney, ureter and bladder will be randomized to receive nifedipine, tamsulosin or placebo (400 participants per arm) for a maximum of 28 days. The primary clinical outcome is spontaneous passage of ureteric stones at 4 weeks (defined as no further intervention required to facilitate stone passage). The primary economic outcome is a reduction in the incremental cost per quality-adjusted life years, determined at 12 weeks. The analysis will be based on all participants as randomized (intention to treat). The trial has 90% power with a type I error rate of 5% to detect a 10% increase in primary outcome between the tamsulosin and nifedipine treatment groups. [ABSTRACT FROM AUTHOR]

Background Postal questionnaires are simple and economical for collecting outcome data for randomised controlled trials (RCTs) but are prone to non-response. In the RECORD trial (a large pragmatic publicly funded RCT in UK) non-responders were sent a reminder and another questionnaire at 1 year, of which 40% were returned. In subsequent years we investigated the effect of an advance telephone call to non-responders on responses rate to reminder questionnaires and the next questionnaire 4 months later. Methods Non-responders to annual questionnaires were randomised to receive a telephone call from the trial office ahead of the reminder questionnaire in addition to the usual reminder schedule (n = 390) or to a control group that received the usual reminder schedule only (n = 363). The primary outcome was response to the reminder questionnaire within 21 days; secondary outcomes were response to a questionnaire 4 months later; completeness of quality of life instruments; and the number of participants declining further follow-up. Results are presented as odds ratios from a logistic regression intention-to-treat (ITT) analysis and then percentage difference and 95% confidence intervals (CI) for both ITT and average treatment effect on the treated (ATT) analyses. Results The proportions that responded were 67.8% (265/390) in the intervention group compared to 62.5% (227/363) in the control group. The ITT estimate was a 5.4% increase (95% CI -1.4 to 12.2). Four months later percentages responding were 51.8% (202) and 42.7% (155). The ITT estimate was a 9.1% increase (95% CI 2.0 to 16.2). In the intervention group 12.3% (48/390) of participants were not telephoned because questionnaires were returned before the scheduled telephone call. ATT estimates adjusting for this were 6.2% (95% CI -1.6 to 14.0) and 10.4% (95% CI 2.2 to 18.5), respectively. Conclusions The telephone call resulted in a slight increase in response to the reminder questionnaire, however at 4 months later the proportion in the telephoned group responding was greater. This study suggests that pre-notification telephone calls may only be worthwhile if further questionnaires are to be sent out soon after reminder questionnaires. Trial registration Current Clinical Trials ISRCTN51647438 [ABSTRACT FROM AUTHOR]

Abstract: Pushing and pulling account for nearly half of all manual material handling tasks. The purpose of this investigation was to develop a 3-D spatial muscle activity map for the right upper extremity during pushing and pulling tasks. Nineteen males performed 140 ramped directional hand exertions (70 push; 70 pull) at locations along three axes aligned with the anatomical planes. Electromyography (EMG) of 14 sites on the right upper extremity was recorded. Two directional 3-way repeated measures ANOVAs assessed the influence of hand position on EMG. Hand position and exertion direction influenced total and individual muscle demand. During pulling exertions, all three hand location parameters influenced total muscle activity (p < 0.001) and similarly in pushing exertions (p < 0.002), though less pronounced than in pulling. Data were used to create equations to predict the muscle activity of untested hand locations for novel work design scenarios. [Copyright &y& Elsevier]

Background: Laparoscopic surgery has become the preferred approach for many procedures because of reduced post-operative pain, better recovery, shorter hospital stay and improved cosmesis. Single incision laparoscopic surgery is one of the many recent variants where either standard ports or a specially designed single multi-channel port is introduced through a single skin incision. While the cosmetic advantage of this is obvious, the evidence base for claims of reduced morbidity and better post-operative recovery is weak. This study aims to compare the effectiveness of single port/incision laparoscopic appendicectomy with standard three-port laparoscopic appendicectomy in adult patients at six weeks post-surgery. We also wish to assess the feasibility of a multicentre randomised controlled trial comparing single port/incision laparoscopic surgery with standard three-port laparoscopic surgery for other surgical techniques. Methods and design: Patients diagnosed with suspected appendicitis and requiring surgical treatment will be randomised to receive either standard three-port or single incision laparoscopic surgery. Data will be collected from clinical notes, operation notes and patient reported questionnaires. The following outcomes will be considered: 1. Effectiveness of the surgical procedure in terms of: • patient reported outcomes • clinical outcomes • resource use 2. Feasibility of conducting a randomised controlled trial (RCT) in the emergency surgical setting by quantifying: • patient eligibility • randomisation acceptability • feasibility of blinding participants to the intervention received • completion rates of case report forms and patient reported questionnaires Trial registration: ISRCTN66443895 (assigned 10 March 2011, first patient randomised 09 January 2011) [ABSTRACT FROM AUTHOR]