Mixing with the radiofrequency single-electron transistor

By configuring a radio-frequency single-electron transistor as a mixer, we demonstrate a unique implementation of this device, that achieves good charge sensitivity with large bandwidth about a tunable center frequency. In our implementation we achieve a measurement bandwidth of 16 MHz, with a tunable center frequency from 0 to 1.2 GHz, demonstrated with the transistor operating at 300 mK. Ultimately this device is limited in center frequency by the RC time of the transistor's center island, which for our device is ~ 1.6 GHz, close to the measured value. The measurement bandwidth is determined by the quality factor of the readout tank circuit.Comment: Submitted to APL september 200

Noise-enabled precision measurements of a Duffing nanomechanical resonator

We report quantitative experimental measurements of the nonlinear response of a radiofrequency mechanical resonator, with very high quality factor, driven by a large swept-frequency force. We directly measure the noise-free transition dynamics between the two basins of attraction that appear in the nonlinear regime, and find good agreement with those predicted by the one-dimensional Duffing equation of motion. We then measure the response of the transition rates to controlled levels of white noise, and extract the activation energy from each basin. The measurements of the noise-induced transitions allow us to obtain precise values for the critical frequencies, the natural resonance frequency, and the cubic nonlinear parameter in the Duffing oscillator, with direct applications to high sensitivity parametric sensors based on these resonators.Comment: 5 pages, 5 figure

Nanoelectromechanical Resonator Arrays for Ultrafast, Gas-Phase Chromatographic Chemical Analysis

Miniaturized gas chromatography (GC) systems can provide fast, quantitative analysis of chemical vapors in an ultrasmall package. We describe a chemical sensor technology based on resonant nanoelectromechanical systems (NEMS) mass detectors that provides the speed, sensitivity, specificity, and size required by the microscale GC paradigm. Such NEMS sensors have demonstrated detection of subparts per billion (ppb) concentrations of a phosphonate analyte. By combining two channels of NEMS detection with an ultrafast GC front-end, chromatographic analysis of 13 chemicals was performed within a 5 s time window

Patient-doctor agreement on recall of clinical trial discussion across cultures

Background The purpose was to investigate patient-doctor agreement on clinical trial discussion cross-culturally. Methods In the International Breast Cancer Study Group Trial 33-03 on shared decision-making for early breast cancer in Australian/New Zealand (ANZ) and Swiss/German/Austrian (SGA) centers, doctor and patient characteristics plus doctor stress and burnout were assessed. Within 2 weeks post-consultation about treatment options, the doctor and patient reported independently, whether a trial was discussed. Odds ratios of agreement for covariables were estimated by generalized estimating equations for each language cohort, with doctor as a random effect. Results In ANZ, 21 doctors and 339 patients were eligible; in SGA, 41 doctors and 427 patients. In cases where the doctor indicated ‘no trial discussed', 82% of both ANZ and SGA patients agreed; if the doctor indicated ‘trial discussed', 50% of ANZ and 38% of SGA patients agreed, respectively. Factors associated with higher agreement were: low tumor grade and fewer patients recruited into clinical trials in SGA; public institution, patient born in ANZ (versus other), higher doctor depersonalization and personal accomplishment in ANZ. Conclusion There is discordance between oncologists and their patients regarding clinical trial discussion, particularly when the doctor indicates that a trial was discussed. Factors contributing to this agreement vary by cultur

Evaluation of Outcomes for Psychosis and Epilepsy Treatment Delivered by Primary Health Care Workers in Nepal: A Cohort Study.

Background: Most evaluations of task-shifting have focused on common mental disorders. Much less work has been done on severe mental neurological and substance use (MNS) disorders, such as chronic psychosis and epilepsy. Given the high burden associated with severe MNS and the lack of mental health professionals in low and middle income countries, evaluations on the impact of task-shifting for these disorders are important. Methods: In a rural district of Nepal, a community mental health program, based on World Health Organization\u27s Mental Health Gap Action Programme guidelines, was evaluated using a cohort study design. People with epilepsy and psychotic disorders were interviewed at treatment initiation and at 12-month follow-up. We also compared a group that was offered a comprehensive package of care (medication combined with psychosocial interventions, such as counselling and peer support groups) to a group that received medication only. Results: One-hundred nineteen persons were enrolled in the epilepsy cohort (EC) and 85 in the psychosis cohort (PC). The patients were enrolled in either the comprehensive package (n = 157) or medication only (n = 47). There was significant improvement (P \u3c 0.0001) in psychosis symptoms (PC: Z = 6.78, r = 0.80) and depressive symptoms (EC: Z = 7.43, r = 0.73; PC: Z = 6.02, r = 0.70), seizures (EC: Z = 6.78), functional disability (EC: Z = 6.38, r = 0.67; PC: Z = 4.60, r = 0.57), family and caregiver burden (EC: Z = 8.09, r = 0.85; PC: Z = 6.81, r = 0.84), and social behaviour (PC: Z = 5.94, r = 0.84). There was greater risk reduction for recent seizures among people with epilepsy in the comprehensive treatment package vs. medication only (risk ratio = 0.52, 95% CI 0.29-0.95; P = 0.03); no other significant differences were observed between treatment arms. Conclusions: A community mental health program in Nepal, implemented by non-specialists, resulted in moderate to large effects among people with epilepsy or psychosis. A comprehensive package of care, including counselling and patient support groups, appears to offer added clinical benefits for patients with epilepsy. For people with psychosis, the basic package of care (i.e., psychotropic medications) performed similar to the comprehensive package, suggesting a less resource-intensive package may offer comparable results

Hospital-based preventative interventions for people experiencing homelessness in high-income countries: A systematic review

BACKGROUND: People experiencing homelessness have significant unmet needs and high rates of unplanned care. We aimed to describe preventative interventions, defined in their broadest sense, for people experiencing homelessness in a hospital context. Secondary aims included mapping outcomes and assessing intervention effectiveness. METHODS: We searched online databases (MEDLINE, Embase, PsycINFO, HMIC, CINAHL, Web of Science, Cochrane Library) from 1999–2019 and conducted backward and forward citation searches to 31 December 2020 (PROSPERO CRD42019154036). We included quantitative studies in emergency and inpatient settings measuring health or social outcomes for adults experiencing homelessness in high income countries. We assessed rigour using the “Quality Assessment Tool for Quantitative Studies” and summarised findings using descriptive quantitative methods, a binomial test, a Harvest Plot, and narrative synthesis. We used PRISMA and SWiM reporting guidelines. FINDINGS: Twenty-eight studies identified eight intervention types: care coordination (n=18); advocacy, support, and outreach (n=13); social welfare assistance (n=13); discharge planning (n=12); homelessness identification (n=6); psychological therapy and treatment (n=6); infectious disease prevention (n=5); and screening, treatment, and referrals (n=5). The evidence strength was weak (n=16) to moderate (n=10), with two high quality randomised controlled trials. We identified six outcome categories with potential benefits observed for psychosocial outcomes, including housing (11/13 studies, 95%CI=54.6–98.1%, p=0.023), healthcare use (14/17, 56.6–96.2%, p=0.013), and healthcare costs (8/8, 63.1–100%, p=0.008). Benefits were less likely for health outcomes (4/5, 28.3–99.5%, p=0.375), integration with onward care (2/4, 6.8–93.2%, p=1.000), and feasibility/acceptability (5/6, 35.9–99.6%, p=0.219), but confidence intervals were very wide. We observed no harms. Most studies showing potential benefits were multi-component interventions. INTERPRETATION: Hospital-based preventative interventions for people experiencing homelessness are potentially beneficial, but more rigorous research is needed. In the context of high needs and extreme inequities, policymakers and healthcare providers may consider implementing multi-component preventative interventions. FUNDING: SL is supported by an NIHR Clinical Doctoral Research Fellowship (ICA-CDRF-2016-02-042). JD is supported by an NIHR School of Public Health Research Pre-doctoral Fellowship (NU-004252). RWA is supported by a Wellcome Clinical Research Career Development Fellowship (206602)

Siren songs or path to salvation? Interpreting the visions of web technology at a UK regional newspaper in crisis, 2006-11

A 5-year case study of an established regional newspaper in Britain investigates journalists about their perceptions of convergence in digital technologies. This research is the first ethnographic longitudinal case study of a UK regional newspaper. Although conforming to some trends observed in the wider field of scholarship, the analysis adds to skepticism about any linear or directional views of innovation and adoption: the Northern Echo newspaper journalists were observed to have revised their opinions of optimum Web practices, and sometimes radically reversed policies. Technology is seen in the period as a fluid, amorphous entity. Central corporate authority appeared to diminish in the period as part of a wider reduction in formalism. Questioning functionalist notions of the market, the study suggests cause and effect models of change are often subverted by contradictory perceptions of particular actions. Meanwhile, during technological evolution, the ‘professional imagination’ can be understood as strongly reflecting the parent print culture and its routines, despite pioneering a new convergence partnership with an independent television company

Effect of dialysate composition on intercompartmental fluid shift

Effect of dialysate composition on intercompartmental fluid shift. Effect of dialysate composition on intercompartmental fluid shift and hemodynamics was studied in 12 patients during 1.5 or 2 hours of hemodialysis without net ultrafiltration, using high (H;Na 154 mmol/liter), normal (N;Na 140 mmol/liter) or low (L:Na 126 mmol/liter) concentration dialysate. H dialysate was associated with a small (0.9%) increase in blood volume, a larger increase in plasma volume and a decrease in erythrocyte volume. L dialysate resulted in a 2.3% decrease in blood volume, a larger decrease in plasma volume and an increase in erythrocyte volume. N dialysate gave results which were intermediately between the other two dialysis conditions. There was no difference in the post-dialysis mean arterial pressure between the groups, although heart rate increased more during H dialysis than during the other two conditions. Change in blood and erythrocyte volume correlated significantly with change in plasma Na concentration and osmolality, but not with change in plasma urea concentration. We conclude that dialysate composition affects the movement of water into and out of the plasma and erythrocytes in a manner that can be accounted for by altered plasma concentrations of osmotically active substances

Effects of excitotoxic striatal lesions on single unit activity in globus pallidus and entopeduncular nucleus of the cat

Striatal projections to the globus pallidus and entopeduncular nucleus are thought to be GABAergic and inhibitory. Thus, striatal lesions might be expected to increase the spontaneous discharge rate of neurons in these nuclei. To test this prediction, we recorded spontaneous single unit activity from awake cats sitting quietly before and 7-160 days after striatal lesions. Striatal lesions were produced by injecting ibotenic acid into the caudate nucleus and putamen. Median, standard deviation, mean, and coefficient of variation of the interspike intervals were calculated for each unit. In globus pallidus the striatal lesion resulted in a significant decrease in median interval length, i.e. an increase in the discharge rate. The prelesion median of 36 ms (S.E.M. = 2.3) decreased 11% to a postlesion value of 32 ms (S.E.M. = 2.1.). The lesion also resulted in a significant decrease in the variability of interspike intervals. The coefficient of variation, 1.31 (S.E.M. = 0.08) before the lesion, decreased 25% to 0.97 (S.E.M. = 0.06) after the lesion. In entopeduncular nucleus, the lesion had no statistically significant effect on the rate of activity, but a significant decrease in the variability of activity occurred. The median interval was 33 ms (S.E.M. = 3.3) before the lesion and decreased 2% to 32 ms (S.E.M. = 2.4). The coefficient of variation decreased 48% from 1.44 (S.E.M. = 0.1) to 0.73 (S.E.M. = 0.03). These observations support the hypothesis that loss of GABAergic inputs to the globus pallidus results in disinhibition. The discharge rate in entopeduncular nucleus was not affected by the striatal lesion, suggesting that striatal substance P or subthalamic excitatory inputs may have a role in regulating discharge rate in the entopeduncular nucleus.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27691/1/0000075.pd