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In preparation for a multisite antibiotic stewardship intervention, we assessed knowledge and attitudes toward management of asymptomatic bacteriuria (ASB) plus teamwork and safety climate among providers, nurses, and clinical nurse assistants (CNAs).
Prospective surveys during January–June 2018.
All acute and long-term care units of 4 Veterans’ Affairs facilities.
The survey instrument included 2 previously tested subcomponents: the Kicking CAUTI survey (ASB knowledge and attitudes) and the Safety Attitudes Questionnaire (SAQ).
A total of 534 surveys were completed, with an overall response rate of 65%. Cognitive biases impacting management of ASB were identified. For example, providers presented with a case scenario of an asymptomatic patient with a positive urine culture were more likely to give antibiotics if the organism was resistant to antibiotics. Additionally, more than 80% of both nurses and CNAs indicated that foul smell is an appropriate indication for a urine culture. We found significant interprofessional differences in teamwork and safety climate (defined as attitudes about issues relevant to patient safety), with CNAs having highest scores and resident physicians having the lowest scores on self-reported perceptions of teamwork and safety climates (P < .001). Among providers, higher safety-climate scores were significantly associated with appropriate risk perceptions related to ASB, whereas social norms concerning ASB management were correlated with higher teamwork climate ratings.
Our survey revealed substantial misunderstanding regarding management of ASB among providers, nurses, and CNAs. Educating and empowering these professionals to discourage unnecessary urine culturing and inappropriate antibiotic use will be key components of antibiotic stewardship efforts.
Although food from grazed animals is increasingly sought by consumers because of perceived animal welfare advantages, grazing systems provide the farmer and the animal with unique challenges. The system is dependent almost daily on the climate for feed supply, with the importation of large amounts of feed from off farm, and associated labour and mechanisation costs, sometimes reducing economic viability. Furthermore, the cow may have to walk long distances and be able to harvest feed efficiently in a highly competitive environment because of the need for high levels of pasture utilisation. She must, also, be: (1) highly fertile, with a requirement for pregnancy within ~80 days post-calving; (2) ‘easy care’, because of the need for the management of large herds with limited labour; (3) able to walk long distances; and (4) robust to changes in feed supply and quality, so that short-term nutritional insults do not unduly influence her production and reproduction cycles. These are very different and are in addition to demands placed on cows in housed systems offered pre-made mixed rations. Furthermore, additional demands in environmental sustainability and animal welfare, in conjunction with the need for greater system-level biological efficiency (i.e. ‘sustainable intensification’), will add to the ‘robustness’ requirements of cows in the future. Increasingly, there is evidence that certain genotypes of cows perform better or worse in grazing systems, indicating a genotype×environment interaction. This has led to the development of tailored breeding objectives within countries for important heritable traits to maximise the profitability and sustainability of their production system. To date, these breeding objectives have focussed on the more easily measured traits and those of highest relative economic importance. In the future, there will be greater emphasis on more difficult to measure traits that are important to the quality of life of the animal in each production system and to reduce the system’s environmental footprint.
The benefit of mandibular advancement devices in patients with sleep-disordered breathing and as a potential option for obstructive sleep apnoea syndrome is well recognised. Their use in the setting of epilepsy or other seizure disorders is typically contraindicated.
A 48-year-old patient with a history of poorly controlled epilepsy and obstructive sleep apnoea syndrome was referred for ENT review for possible tracheostomy. The patient was wheelchair-bound with 24-hour continuous positive airway pressure, but sleep studies demonstrated persistent, severe episodes of apnoea and notable sleep disturbance. Sleep nasendoscopy demonstrated marked improvement on capnography with the laryngeal mask airway in situ, and this was maintained with mandibular advancement using jaw thrust following removal of the laryngeal mask airway. A mandibular advancement device was subsequently trialled; this had no subjective benefit for the patient, but the seizures resolved and control of apnoea was achieved with the combination of a mandibular advancement device and continuous positive airway pressure.
This paper highlights a novel application of mandibular advancement devices, used in combination with continuous positive airway pressure, which resulted in complete resolution of sleep deprivation and apnoea-induced epileptic events.
Anti-retroviral therapy (ART) regimes for HIV are associated with raised levels of circulating triglycerides (TGs) in western populations. However, there are limited data on the impact of ART on cardiometabolic risk in sub-Saharan African (SSA) populations.
Pooled analyses of 14 studies comprising 21 023 individuals, on whom relevant cardiometabolic risk factors (including TG), HIV and ART status were assessed between 2003 and 2014, in SSA. The association between ART and raised TG (>2.3 mmol/L) was analysed using regression models.
Among 10 615 individuals, ART was associated with a two-fold higher probability of raised TG (RR 2.05, 95% CI 1.51–2.77, I2 = 45.2%). The associations between ART and raised blood pressure, glucose, HbA1c, and other lipids were inconsistent across studies.
Evidence from this study confirms the association of ART with raised TG in SSA populations. Given the possible causal effect of raised TG on cardiovascular disease (CVD), the evidence highlights the need for prospective studies to clarify the impact of long term ART on CVD outcomes in SSA.
Pre-1990 published responses to supplementation at pasture ranged from 0.4 to 0.6kg milk/kg concentrate fed. However since 1990 higher responses to concentrate supplementation at pasture have been published (Delaby 2001). The objective of this study was to determine if milk production responses of Holstein-Friesian dairy cows to concentrate supplementation at pasture are influenced by genetic merit (milk yield potential) in a spring calving grass based system of milk production.
Background: Disgust is thought to play a prominent role in multiple anxiety disorders and fears, including spider phobia, though little attention has been given to specific treatment strategies that may be effective for multiple disgust-based fears. Aims: In the present study, we evaluated contamination-focused exposure as a potential transdiagnostic treatment strategy for disgust-based fears in a spider fearful sample. Method: Women with significant spider fear were randomized to three 30-minute sessions of exposure therapy involving repeated contact with a dirt mixture (n=17) or a waitlist control condition (n=17). Assessments of spider fear and disgust were administered at baseline and at one-week posttreatment. Results: At high (but not low) levels of pretreatment disgust propensity, exposure led to lower in vivo spider fear and perceived danger than waitlist, though exposure had no effects on spider-related disgust. Similar effects of exposure on spider fear were found at high levels of pretreatment spider-related disgust. Exposure also reduced fear and danger perceptions, but not disgust, related to a separate contamination assessment (touching a toilet). No effects of treatment were found on self-report measures of spider fear or disgust propensity. Conclusions: These findings suggest contamination-focused exposure therapy may be an effective transdiagnostic treatment strategy for individuals with elevated disgust propensity. Limitations and directions for future research are discussed.
Dissolved inorganic carbon (DIC) is the main acid buffer in forested lake watersheds in Canada. We used carbon isotopes (13C, 14C) to evaluate the production and cycling of DIC in an acid-sensitive lake watershed of the Precambrian Shield. Soil CO2, groundwater and stream DIC were characterized chemically and isotopically. Soil CO2 concentration profiles reflect both changes in production and in losses due to diffusion. δ13C soil CO2 profiles (δ13C values of −23‰ in summer, slightly enriched during the fall and −25%‰ during the winter) are a reflection of the isotopic composition of the sources and changes in isotopic fractionation due to diffusion. Carbon isotopic composition (13C, 14C) of the groundwater and stream DIC clearly indicate that weathering of silicates by soil CO2 is the main source of DIC in these watersheds. 14C data show that, in addition to recent groundwater, an older groundwater component with depleted 14C activity is also present in the bedrock. The carbon isotope pattern in the groundwater also implies that, besides the main springtime recharge events, contributions to the groundwater may also occur during late winter/early spring.
The Murchison Widefield Array is a new low-frequency interferometric radio telescope built in Western Australia at one of the locations of the future Square Kilometre Array. We describe the automated radio-frequency interference detection strategy implemented for the Murchison Widefield Array, which is based on the aoflagger platform, and present 72–231 MHz radio-frequency interference statistics from 10 observing nights. Radio-frequency interference detection removes 1.1% of the data. Radio-frequency interference from digital TV is observed 3% of the time due to occasional ionospheric or atmospheric propagation. After radio-frequency interference detection and excision, almost all data can be calibrated and imaged without further radio-frequency interference mitigation efforts, including observations within the FM and digital TV bands. The results are compared to a previously published Low-Frequency Array radio-frequency interference survey. The remote location of the Murchison Widefield Array results in a substantially cleaner radio-frequency interference environment compared to Low-Frequency Array’s radio environment, but adequate detection of radio-frequency interference is still required before data can be analysed. We include specific recommendations designed to make the Square Kilometre Array more robust to radio-frequency interference, including: the availability of sufficient computing power for radio-frequency interference detection; accounting for radio-frequency interference in the receiver design; a smooth band-pass response; and the capability of radio-frequency interference detection at high time and frequency resolution (second and kHz-scale respectively).
Depression is characterized by poor executive function, but – counterintuitively – in some studies, it has been associated with highly accurate performance on certain cognitively demanding tasks. The psychological mechanisms responsible for this paradoxical finding are unclear. To address this issue, we applied a drift diffusion model (DDM) to flanker task data from depressed and healthy adults participating in the multi-site Establishing Moderators and Biosignatures of Antidepressant Response for Clinical Care for Depression (EMBARC) study.
One hundred unmedicated, depressed adults and 40 healthy controls completed a flanker task. We investigated the effect of flanker interference on accuracy and response time, and used the DDM to examine group differences in three cognitive processes: prepotent response bias (tendency to respond to the distracting flankers), response inhibition (necessary to resist prepotency), and executive control (required for execution of correct response on incongruent trials).
Consistent with prior reports, depressed participants responded more slowly and accurately than controls on incongruent trials. The DDM indicated that although executive control was sluggish in depressed participants, this was more than offset by decreased prepotent response bias. Among the depressed participants, anhedonia was negatively correlated with a parameter indexing the speed of executive control (r = −0.28, p = 0.007).
Executive control was delayed in depression but this was counterbalanced by reduced prepotent response bias, demonstrating how participants with executive function deficits can nevertheless perform accurately in a cognitive control task. Drawing on data from neural network simulations, we speculate that these results may reflect tonically reduced striatal dopamine in depression.
Individuals with major depressive disorder (MDD) are characterized by maladaptive responses to both positive and negative outcomes, which have been linked to localized abnormal activations in cortical and striatal brain regions. However, the exact neural circuitry implicated in such abnormalities remains largely unexplored.
In this study 26 unmedicated adults with MDD and 29 matched healthy controls (HCs) completed a monetary incentive delay task during functional magnetic resonance imaging (fMRI). Psychophysiological interaction (PPI) analyses probed group differences in connectivity separately in response to positive and negative outcomes (i.e. monetary gains and penalties).
Relative to HCs, MDD subjects displayed decreased connectivity between the caudate and dorsal anterior cingulate cortex (dACC) in response to monetary gains, yet increased connectivity between the caudate and a different, more rostral, dACC subregion in response to monetary penalties. Moreover, exploratory analyses of 14 MDD patients who completed a 12-week, double-blind, placebo-controlled clinical trial after the baseline fMRI scans indicated that a more normative pattern of cortico-striatal connectivity pre-treatment was associated with greater improvement in symptoms 12 weeks later.
These results identify the caudate as a region with dissociable incentive-dependent dACC connectivity abnormalities in MDD, and provide initial evidence that cortico-striatal circuitry may play a role in MDD treatment response. Given the role of cortico-striatal circuitry in encoding action–outcome contingencies, such dysregulated connectivity may relate to the prominent disruptions in goal-directed behavior that characterize MDD.
The Gemini Planet Imager (GPI) is a high contrast coronagraph designed to directly image exoplanets and circumstellar disks. GPI includes a polarimetry mode designed to characterize dust grains and enhance the contrast of scattered, polarized light by a factor of 100. Reflections and birefringence of optics within the optical train induce a polarization signature that needs to be measured a priori and calibrated out during data reduction. Here we report on the results of an extensive laboratory characterization campaign of the polarimetry mode. The linear instrumental polarization has been measured in 4 GPI passbands and found to be between 3.5 ± 0.3 % at 1.0 micron and 1.1 ± 0.3 % at 2.0 microns. Modulation efficiency has been measured to be 94% at 1.0 micron increasing to 97% at 2.0 microns. Stability has been shown to better than 0.6% over timescales of ~ 3 months and over cool down cycles. The tests show that GPI passes all polarimetry design requirements and should be able to measure circumstellar disk linear polarization to 1% accuracy.
We estimated prevalence and incidence of liver condition outcomes, and costs to the health service of diagnosed hepatitis B virus (HBV) in Tayside, UK. HBV patients were identified from electronic virology data between 1989 and 2003. The health resource costs of HBV for surface antigen-positive (HBsAg+) patients and HBV (HBsAg+ or immune, i.e. recovered) patients were calculated. A total of 633 patients had HBV (275 HBsAg+), and were more likely to be male (62% vs. 48%), older (mean age 42·6 vs. 39·2 years) and deprived than the general population. The prevalence of immune individuals increased steadily. Post-HBV diagnosis, 24% of immune and 13% of HBsAg+ patients were diagnosed with a liver condition. The median cost per immune patient (£3023) was greater than per HBsAg+ patient (£1498) (P = 0·02). While increasing prevalence of immune HBV patients highlights an increase in screening and treatment, the costs associated with this group are high.
In Scotland, an estimated 1% of the population is infected with hepatitis C virus (HCV). There is ethnic diversity in Scotland, with a large Pakistani sub-population. Our aim was to investigate the prevalence of HCV in an immigrant Pakistani population and effectiveness of an outreach testing intervention. We arranged a series of HCV awareness meetings at the mosques and Pakistani Women's centre in the city of Dundee. Thereafter short-term outreach HCV testing clinics were set up in the same venues. Venous blood samples were obtained and tested for HCV IgG and HbsAg. A short questionnaire was also completed. In total, 177 individuals volunteered for testing, out of an estimated 250 who attended meetings and a total Pakistani population in Dundee of 1723. Of those tested 170 were Scottish Pakistanis (159 first generation, 11 second generation). There were 145 (85·2%) men. The mean age was 45·11 (±s.d. 16·7) years. Seven (4·1%) individuals in the cohort were anti-HCV positive. Five (2·9%) were found to have HCV RNA by PCR. Only one patient had chronic hepatitis B infection. All patients with positive results were seen in the liver clinic for consideration of treatment. We have demonstrated that immigrant Pakistanis retain a higher prevalence of HCV compared to the population of their adopted country. Outreach targeted testing in this group can be achieved using religious and cultural gatherings, with only modest investment in staff time.
Highly purified single-wall carbon nanotubes (SWCNT) were investigated for use as an anode material for thin film lithium ion batteries. The high purity nanotubes were obtained through chemical refinement of soot generated by pulsed laser ablation. The purity of the nanotubes was determined via thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. The specific surface area and lithium capacity of the SWCNT's was compared to that of other conventional anode materials (i.e., carbon black, graphite, and multi-walled carbon nanotubes). The Brunauer, Emmett, and Teller (BET) technique based on nitrogen adsorption was used to measure the specific surface area of the various anode materials. The SWCNT's exhibited a specific surface area on the order of 915 m2/g, much higher than the other carbonaceous materials. Cyclic voltammetric behavior and the lithium-ion capacity of the materials were measured using a standard 3-electrode electrochemical cell. The cyclic voltammetry showed evidence of “staging” that was similar to other carbonaceous materials. The electrochemical discharge capacity of the purified single walled carbon nanotubes was in excess of 1300 mAh/g after 30 charge/discharge cycles when tested using a current density of 20μA/cm2.
The hydrogen storage properties of carbon single-wall and multi-wall nanotubes (SWNTs and MWNTs), graphitic nanofibers, and other nanostructured carbons have recently become the subject of considerable debate. Reported capacities range from ∼ 0–60 wt%. Hot wire chemical vapor deposition (HWCVD) has recently been adapted for a continuous growth process for high-density carbon MWNTs. Multi-wall nanotube growth is optimized in 1:5 CH4:Ar at 150 Torr with reactor temperatures of 400 and 550°C for static and flowing gases, respectively. Ferrocene is employed to provide a gas-phase catalyst. Highly graphitic nanotubes can be continuously deposited with iron content as low as 15 wt% and carbon impurities below thermal gravimetric analysis detection limits. The MWNTs are simply purified to ∼99.5 wt% with minimal structural damage and with a 75 wt% yield. Hydrogen adsorption is observed for low pressures at near ambient temperatures on the as-synthesized MWNTs containing iron nanoparticles. However, no hydrogen adsorption, is observed at near ambient temperatures for the purified MWNTs or for purified MWNTs that were subsequently combined with iron micro/nano-particles via sonication. These results indicate that an intimate metal/graphitic carbon interaction is required for unanticipated hydrogen adsorption at near ambient conditions.