A vacuum-compatible cylindrical inertial rotation sensor with picoradian sensitivity.

We describe an inertial rotation sensor with a 30-cm cylindrical proof-mass suspended from a pair of 14 µm thick BeCu flexures. The angle between the proof-mass and support structure is measured with a pair of homodyne interferometers, which achieve a noise level of ∼5prad/Hz. The sensor is entirely made of vacuum compatible materials, and the center of mass can be adjusted remotely.

Threat management priorities for conserving Antarctic biodiversity.

Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations.

A cryogenic torsion balance using a liquid-cryogen free, ultra-low vibration cryostat.

We describe a liquid-cryogen free cryostat with ultra-low vibration levels, which allows for continuous operation of a torsion balance at cryogenic temperatures. The apparatus uses a commercially available two-stage pulse-tube cooler and passive vibration isolation. The torsion balance exhibits torque noise levels lower than room temperature thermal noise by a factor of about four in the frequency range of 3-10 mHz, limited by residual seismic motion and by radiative heating of the pendulum body. In addition to lowering thermal noise below room-temperature limits, the low-temperature environment enables novel torsion balance experiments. Currently, the maximum duration of a continuous measurement run is limited by accumulation of cryogenic surface contamination on the optical elements inside the cryostat.

A low-frequency torsion pendulum with interferometric readout.

We describe a torsion pendulum with a large mass-quadrupole moment and a resonant frequency of 2.8 mHz, whose angle is measured using a Michelson interferometer. The system achieved noise levels of ∼200prad/Hz between 0.2 and 30 Hz and ∼10prad/Hz above 100 Hz. Such a system can be applied to a broad range of fields from the study of rotational seismic motion and elastogravity signals to gravitational wave observation and tests of gravity.

Ecto- and endoparasitic nematodes respond differently across sites to changes in precipitation.

Plant parasitic nematodes are among the greatest consumers of primary production in terrestrial ecosystems. Their feeding strategies can be divided into endoparasites and ectoparasites that differ substantially, not only in their damage potential to host tissue and primary production, but also in their susceptibility to environmental changes. Climate change is predicted to increase variability of precipitation in many systems, yet the effects on belowground biodiversity and associated impacts on primary productivity remain poorly understood. To examine the impact of altered precipitation on endo- and ectoparasitic soil nematodes, we conducted a 2-year precipitation manipulation study across an arid, a semiarid, and a mesic grassland. Plant parasite feeding type abundance, functional guilds, and herbivory index in response to precipitation were evaluated. Responses of endo- and ectoparasites to increased precipitation varied by grassland type. There was little response of ectoparasites to increased precipitation although their population declined at the mesic site with increased precipitation. The abundance of endoparasites remained unchanged with increasing precipitation at the arid site, increased at the semiarid, and decreased at the mesic site. The herbivory index followed closely the trends seen in the endoparasites response by stagnating at the arid site, increasing at the semiarid, and decreasing at the mesic site. Our findings suggest that altered precipitation has differing effects on plant parasite feeding strategies as well as functional guilds. This may have important implications for grassland productivity, as plant parasite pressure may exacerbate the effects of climate change on host plants.

Drought suppresses soil predators and promotes root herbivores in mesic, but not in xeric grasslands.

Precipitation changes among years and locations along gradients of mean annual precipitation (MAP). The way those changes interact and affect populations of soil organisms from arid to moist environments remains unknown. Temporal and spatial changes in precipitation could lead to shifts in functional composition of soil communities that are involved in key aspects of ecosystem functioning such as ecosystem primary production and carbon cycling. We experimentally reduced and increased growing-season precipitation for 2 y in field plots at arid, semiarid, and mesic grasslands to investigate temporal and spatial precipitation controls on the abundance and community functional composition of soil nematodes, a hyper-abundant and functionally diverse metazoan in terrestrial ecosystems. We found that total nematode abundance decreased with greater growing-season precipitation following increases in the abundance of predaceous nematodes that consumed and limited the abundance of nematodes lower in the trophic structure, including root feeders. The magnitude of these nematode responses to temporal changes in precipitation increased along the spatial gradient of long-term MAP, and significant effects only occurred at the mesic site. Contrary to the temporal pattern, nematode abundance increased with greater long-term MAP along the spatial gradient from arid to mesic grasslands. The projected increase in the frequency of extreme dry years in mesic grasslands will therefore weaken predation pressure belowground and increase populations of root-feeding nematodes, potentially leading to higher levels of plant infestation and plant damage that would exacerbate the negative effect of drought on ecosystem primary production and C cycling.

Risk factors and prognosis of complicated urinary tract infections caused by Pseudomonas aeruginosa in hospitalized patients: a retrospective multicenter cohort study.

PURPOSE: Complicated urinary tract infections (cUTIs) are among the most frequent health-care-associated infections. In patients with cUTI, Pseudomonas aeruginosa deserves special attention, since it can affect patients with serious underlying conditions. Our aim was to gain insight into the risk factors and prognosis of P. aeruginosa cUTIs in a scenario of increasing multidrug resistance (MDR). METHODS: This was a multinational, retrospective, observational study at 20 hospitals in south and southeastern Europe, Turkey, and Israel including consecutive patients with cUTI hospitalized between January 2013 and December 2014. A mixed-effect logistic regression model was performed to assess risk factors for P. aeruginosa and MDR P. aeruginosa cUTI. RESULTS: Of 1,007 episodes of cUTI, 97 (9.6%) were due to P. aeruginosa. Resistance rates of P. aeruginosa were: antipseudomonal cephalosporins 35 of 97 (36.1%), aminoglycosides 30 of 97 (30.9%), piperacillin-tazobactam 21 of 97 (21.6%), fluoroquinolones 43 of 97 (44.3%), and carbapenems 28 of 97 (28.8%). The MDR rate was 28 of 97 (28.8%). Independent risk factors for P. aeruginosa cUTI were male sex (OR 2.61, 95% CI 1.60-4.27), steroid therapy (OR 2.40, 95% CI 1.10-5.27), bedridden functional status (OR 1.79, 95% CI 0.99-3.25), antibiotic treatment within the previous 30 days (OR 2.34, 95% CI 1.38-3.94), indwelling urinary catheter (OR 2.41, 95% CI 1.43-4.08), and procedures that anatomically modified the urinary tract (OR 2.01, 95% CI 1.04-3.87). Independent risk factors for MDR P. aeruginosa cUTI were age (OR 0.96, 95% CI 0.93-0.99) and anatomical urinary tract modification (OR 4.75, 95% CI 1.06-21.26). Readmission was higher in P. aeruginosa cUTI patients than in other etiologies (23 of 97 [23.7%] vs 144 of 910 [15.8%], P=0.04), while 30-day mortality was not significantly different (seven of 97 [7.2%] vs 77 of 910 [8.5%], P=0.6). CONCLUSION: Patients with P. aeruginosa cUTI had characteristically a serious baseline condition and manipulation of the urinary tract, although their mortality was not higher than that of patients with cUTI caused by other etiologies.

Preoperative oral antibiotic prophylaxis reduces Pseudomonas aeruginosa surgical site infections after elective colorectal surgery: a multicenter prospective cohort study.

BACKGROUND: Healthcare-associated infections caused by Pseudomonas aeruginosa are associated with poor outcomes. However, the role of P. aeruginosa in surgical site infections after colorectal surgery has not been evaluated. The aim of this study was to determine the predictive factors and outcomes of surgical site infections caused by P. aeruginosa after colorectal surgery, with special emphasis on the role of preoperative oral antibiotic prophylaxis. METHODS: We conducted an observational, multicenter, prospective cohort study of all patients undergoing elective colorectal surgery at 10 Spanish hospitals (2011-2014). A logistic regression model was used to identify predictive factors for P. aeruginosa surgical site infections. RESULTS: Out of 3701 patients, 669 (18.1%) developed surgical site infections, and 62 (9.3%) of these were due to P. aeruginosa. The following factors were found to differentiate between P. aeruginosa surgical site infections and those caused by other microorganisms: American Society of Anesthesiologists' score III-IV (67.7% vs 45.5%, p = 0.001, odds ratio (OR) 2.5, 95% confidence interval (95% CI) 1.44-4.39), National Nosocomial Infections Surveillance risk index 1-2 (74.2% vs 44.2%, p < 0.001, OR 3.6, 95% CI 2.01-6.56), duration of surgery ≥75thpercentile (61.3% vs 41.4%, p = 0.003, OR 2.2, 95% CI 1.31-3.83) and oral antibiotic prophylaxis (17.7% vs 33.6%, p = 0.01, OR 0.4, 95% CI 0.21-0.83). Patients with P. aeruginosa surgical site infections were administered antibiotic treatment for a longer duration (median 17 days [interquartile range (IQR) 10-24] vs 13d [IQR 8-20], p = 0.015, OR 1.1, 95% CI 1.00-1.12), had a higher treatment failure rate (30.6% vs 20.8%, p = 0.07, OR 1.7, 95% CI 0.96-2.99), and longer hospitalization (median 22 days [IQR 15-42] vs 19d [IQR 12-28], p = 0.02, OR 1.1, 95% CI 1.00-1.17) than those with surgical site infections due to other microorganisms. Independent predictive factors associated with P. aeruginosa surgical site infections were the National Nosocomial Infections Surveillance risk index 1-2 (OR 2.3, 95% CI 1.03-5.40) and the use of oral antibiotic prophylaxis (OR 0.4, 95% CI 0.23-0.90). CONCLUSIONS: We observed that surgical site infections due to P. aeruginosa are associated with a higher National Nosocomial Infections Surveillance risk index, poor outcomes, and lack of preoperative oral antibiotic prophylaxis. These findings can aid in establishing specific preventive measures and appropriate empirical antibiotic treatment.

Multistate modelling to estimate excess length of stay and risk of death associated with organ/space infection after elective colorectal surgery.

BACKGROUND: Accounting for time-dependency and competing events are strongly recommended to estimate excess length of stay (LOS) and risk of death associated with healthcare-associated infections. AIM: To assess the effect of organ/space (OS) surgical site infection (SSI) on excess LOS and in-hospital mortality in patients undergoing elective colorectal surgery (ECS). METHODS: A multicentre prospective adult cohort undergoing ECS, January 2012 to December 2014, at 10 Spanish hospitals was used. SSI was considered the time-varying exposure and defined as incisional (superficial and deep) or OS. Discharge alive and death were the study endpoints. The mean excess LOS was estimated using a multistate model which provided a weighted average based on the states patients passed through. Multivariate Cox regression models were used to assess the effect of OS-SSI on risk of discharge alive or in-hospital mortality. FINDINGS: Of 2778 patients, 343 (12.3%) developed SSI: 194 (7%) OS-SSI and 149 (5.3%) incisional SSI. Compared to incisional SSI or no infection, OS-SSI prolonged LOS by 4.2 days (95% confidence interval (CI): 4.1-4.3) and 9 days (8.9-9.1), respectively, reduced the risk of discharge alive (adjusted hazard ratio (aHR): 0.36 (95% CI: 0.28-0.47) and aHR: 0.17 (0.14-0.21), respectively), and increased the risk of in-hospital mortality (aHR: 8.02 (1.03-62.9) and aHR: 10.7 (3.7-30.9), respectively). CONCLUSION: OS-SSI substantially extended LOS and increased risk of death in patients undergoing ECS. These results reinforce OS-SSI as the SSI with the highest health burden in ECS.

Interventions to decrease short-term peripheral venous catheter-related bloodstream infections: impact on incidence and mortality.

BACKGROUND: Short-term peripheral venous catheters are a significant source of healthcare-acquired bloodstream infections and a preventable cause of death. AIM: To assess the effectiveness of interventions applied to reduce the incidence and mortality associated with short-term peripheral venous catheter-related bloodstream infections (PVCR-BSIs). METHODS: The intervention included continuous PVCR-BSI surveillance, implementation of preventive measures related to catheter insertion and maintenance in accordance with evidence-based recommendations and the hospital's own data, front-line staff educational campaigns, and assessment of adherence to hospital guidelines by ward rounds. A Poisson regression model was used to estimate the trend of rate per year. FINDINGS: From January 2003 to December 2016, 227 episodes of PVCR-BSI were identified among hospitalized patients at a university hospital. The mean age of patients was 67 years (standard deviation 14 years), 69% were male and the median Charlson score was 3 (interquartile range 2-5). Staphylococcus aureus caused 115 (50.7%) episodes. Thirty-day mortality was 13.2%. After implementation of the intervention, the incidence of PVCR-BSIs decreased significantly from 30 episodes in 2003 (1.17 episodes/10,000 patient-days) to eight episodes in 2016 (0.36/10,000 patient-days). The number of episodes caused by S. aureus decreased from 18 episodes in 2003 (0.70/10,000 patient-days) to three episodes in 2016 (0.14/10,000 patient-day), and mortality decreased from seven cases in 2003 (0.27/10,000 patient-days) to zero cases in 2016 (0.00/10,000 patient-days). CONCLUSIONS: Surveillance, implementation of a multi-modal strategy and periodical assessment of healthcare workers' adherence to hospital guidelines led to a sustained reduction in PVCR-BSIs. This reduction had a major impact on S. aureus BSI rates and associated mortality.

Metal removal from soil leachates using DTPA-functionalised maghemite nanoparticles, a potential soil washing technology.

There is significant current interest in the application of magnetic (magnetite or maghemite) nanoparticles functionalised with chelating agents for the environmental remediation of metal contaminated waters and solutions. Whilst there is a body of knowledge about the potential remediation efficacy of such engineered nanoparticles from studies involving synthetic solutions of single metals, there is relatively little data involving mixed-metal solutions and virtually no studies about nanoparticle performance in chemically complex environmental solutions representing those to which a scaled-up nanoremediation process might eventually be applied. Therefore, we investigated the ability of diethylenetriaminepentaacetic acid (DTPA)-functionalised, silica-coated maghemite nanoparticles to extract potentially toxic (Cd, Co, Cu) and "non-toxic" (Ca, Mg) metals from solution (initial [metal] = 10 mg L-1; pH range: 2-8) and to extract a wider range of elements (As, Ca, Cd, Co, Cr, Cu, Mg, Na, Pb, Zn) from leachate obtained from 10 different contaminated soils with variable initial pH, (semi-)metal and dissolved organic carbon (DOC) concentrations. The functionalised nanoparticles could extract the potentially toxic metals with high efficiency (in general >70%) from single metal solutions and with efficiencies that were either unaffected or reduced from the soil leachates. Kd values remained high (>500 L kg-1), even for the soil leachate extractions. Our findings show that DOC and relatively high concentrations of non-toxic elements do not necessarily reduce the efficiency of metal contaminant removal by DTPA-functionalised magnetic nanoparticles and thus demonstrate the remediation potential of such particles when added to chemically complex soil-derived contaminated solutions.

The role of vitamin D in hepatic metastases from colorectal cancer

Colorectal cancer (CRC) represents a significant health burden worldwide, comprising approximately 10% of annual cancer cases globally. Hepatic metastases are the most common site of CRC metastasis, and are the leading cause of death in CRC patients. There is strong epidemiologic evidence for an inverse association between vitamin D status and risk of CRC; however, the role of vitamin D in the natural history of liver metastases has not yet been investigated. Several researchers have proposed hallmarks of metastases; crucially, metastases can be blocked by interrupting just one rate-limiting step. Vitamin D status has been implicated in each proposed hallmark of metastasis. The aim of this review is to examine the potential role for vitamin D in reducing the development of hepatic metastases from CRC and outline the candidate mechanisms by which vitamin D may mediate these effects. The results of ongoing randomised intervention trials are eagerly awaited to determine whether addressing vitamin D insufficiency in CRC patients could reduce the occurrence of liver metastases, and the consequent morbidity and mortality (AU)

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The role of vitamin D in hepatic metastases from colorectal cancer.

Colorectal cancer (CRC) represents a significant health burden worldwide, comprising approximately 10% of annual cancer cases globally. Hepatic metastases are the most common site of CRC metastasis, and are the leading cause of death in CRC patients. There is strong epidemiologic evidence for an inverse association between vitamin D status and risk of CRC; however, the role of vitamin D in the natural history of liver metastases has not yet been investigated. Several researchers have proposed hallmarks of metastases; crucially, metastases can be blocked by interrupting just one rate-limiting step. Vitamin D status has been implicated in each proposed hallmark of metastasis. The aim of this review is to examine the potential role for vitamin D in reducing the development of hepatic metastases from CRC and outline the candidate mechanisms by which vitamin D may mediate these effects. The results of ongoing randomised intervention trials are eagerly awaited to determine whether addressing vitamin D insufficiency in CRC patients could reduce the occurrence of liver metastases, and the consequent morbidity and mortality.

Can teenage novel users perform as well as General Surgery residents upon initial exposure to a robotic surgical system simulator?

New techniques in minimally invasive and robotic surgical platforms require staged curricula to insure proficiency. Scant literature exists as to how much simulation should play a role in training those who have skills in advanced surgical technology. The abilities of novel users may help discriminate if surgically experienced users should start at a higher simulation level or if the tasks are too rudimentary. The study's purpose is to explore the ability of General Surgery residents to gain proficiency on the dVSS as compared to novel users. The hypothesis is that Surgery residents will have increased proficiency in skills acquisition as compared to naive users. Six General Surgery residents at a single institution were compared with six teenagers using metrics measured by the dVSS. Participants were given two 1-h sessions to achieve an MScoreTM in the 90th percentile on each of the five simulations. MScoreTM software compiles a variety of metrics including total time, number of attempts, and high score. Statistical analysis was run using Student's t test. Significance was set at p value <0.05. Total time, attempts, and high score were compared between the two groups. The General Surgery residents took significantly less Total Time to complete Pegboard 1 (PB1) (p = 0.043). No significant difference was evident between the two groups in the other four simulations across the same MScoreTM metrics. A focused look at the energy dissection task revealed that overall score might not be discriminant enough. Our findings indicate that prior medical knowledge or surgical experience does not significantly impact one's ability to acquire new skills on the dVSS. It is recommended that residency-training programs begin to include exposure to robotic technology.

Control of endemic multidrug-resistant Gram-negative bacteria after removal of sinks and implementing a new water-safe policy in an intensive care unit.

BACKGROUND: Contaminated handwashing sinks have been identified as reservoirs that can facilitate colonization/infection of patients with multidrug-resistant (MDR) Gram-negative bacteria (GNB) in intensive care units (ICUs). AIM: To assess the impact of removing patients' sinks and implementing other water-safe strategies on the annual rates of ICU-acquired MDR-GNB. METHODS: This six-year quasi-experimental study was conducted from January 2011 to December 2016. The intervention was carried out in August 2014 in two adult ICU wards with 12 rooms each. To assess the changes in annual MDR-GNB rates before and after the intervention, we used segmented regression analysis of an interrupted time-series. Crude relative risk (RR) rates were also calculated. FINDINGS: The incidence rates of MDR-GNB were 9.15 and 2.20 per 1000 patient-days in the pre- and post-intervention periods, respectively. This yielded a crude RR of acquiring MDR-GNB of 0.24 (95% confidence interval: 0.17-0.34). A significant change in level was observed between the MDR-GNB rate at the first point of the post-intervention period and the rate predicted by the pre-intervention time trend. CONCLUSION: The implementation of a new water-safe policy, which included the removal of sinks from all patient rooms, successfully improved the control of MDR-GNB spread in an ICU with endemic infection. Our results support the contribution of sink use with the incidence of MDR-GNB in endemic environments.

Predictive factors for early- and late-onset surgical site infections in patients undergoing elective colorectal surgery. A multicentre, prospective, cohort study.

BACKGROUND: Surgical site infections (SSIs) are the leading cause of healthcare-associated infections in acute care hospitals in Europe. However, the risk factors for the development of early-onset (EO) and late-onset (LO) SSI have not been elucidated. AIM: This study investigated the predictive factors for EO-SSI and LO-SSI in a large cohort of patients undergoing colorectal surgery. METHODS: We prospectively followed-up adult patients undergoing elective colorectal surgery in 10 hospitals (2011-2014). Patients were divided into three groups: EO-SSI, LO-SSI, or no infection (no-SSI). The cut-off defining EO-SSI and LO-SSI was seven days (median time to SSI development). Different predictive factors for EO-SSI and LO-SSI were analysed, comparing each group with the no-SSI patients. FINDINGS: Of 3701 patients, 320 (8.6%) and 349 (9.4%) developed EO-SSI and LO-SSI, respectively. The rest had no-SSI. Patients with EO-SSI were mostly males, had colon surgery and developed organ-space SSI whereas LO-SSI patients frequently received chemotherapy or radiotherapy and had incisional SSI. Male sex (odds ratio (OR): 1.92; P < 0.001), American Society of Anesthesiologists' physical status >2 (OR: 1.51; P = 0.01), administration of mechanical bowel preparation (OR: 0.7; P = 0.03) and stoma creation (OR: 1.95; P < 0.001) predicted EO-SSI whereas rectal surgery (OR: 1.43; P = 0.03), prolonged surgery (OR: 1.4; P = 0.03) and previous chemotherapy (OR: 1.8; P = 0.03) predicted LO-SSI. CONCLUSION: We found distinctive predictive factors for the development of SSI before and after seven days following elective colorectal surgery. These factors could help establish specific preventive measures in each group.

Training and Service Provision in Cardiovascular CT: International Challenges and Solutions.

PURPOSE OF REVIEW: This manuscript identifies international challenges in cardiovascular CT that may prevent it from becoming a mainstream cardiovascular investigation. It offers potential solutions and a vision to overcome these barriers. RECENT FINDINGS: The acceptance of cardiovascular CT as a mainstream investigation now mandates a root and branch review of how we deliver a technology that is no longer emerging but recommended for mainstream clinical practice. The main challenges include investment in equipment and personnel and a substantial uplift in educational and training opportunities available. This requires revision of existing structures for training and accreditation and a broadening of these opportunities to include radiographers/technologists. The evidence for cardiovascular CT is overwhelming; the same energy and investment witnessed in driving the evidence base for this technology is now required in education and training. Failure to do so risks undermining the academic investment made over the last decade.