51 research outputs found
Inter-library loans: retrospect and prospect
In the United Kingdom, including to a lesser extent Eire, the last
sixty years or so have seen the development of a system of national
and regional inter-library lending of which the library service may be
justly proud. That is not to say that the system which has already
been developed is incapable of improvement, nor that the methods
adopted for the furtherance of library cooperation have always been
the most efficient and economical.
By outlining the main factors in this development, and
noting some possible changes for the future, this study seeks to
evaluate this complex method by which British libraries seek to make
the total bibliographic resources of the country readily available to
those who need access to them. In terms of the cost per item handled
it could be argued that the methods used are relatively inexpensive;
in terms of the total expenditure on duplication of functions throughout
the country, it is certainly a costly operation
âKindness by Postâ: A Mixed-Methods Evaluation of a Participatory Public Mental Health Project
Background
Random acts of kindness can improve wellbeing. However, less is known about the impacts of giving and receiving acts of kindness with strangers on wellbeing and loneliness. Therefore, this studyâs objectives were to evaluate a participatory public mental health project involving sending and receiving a card with goodwill messages, to understand how such acts of kindness influence wellbeing and loneliness, and to investigate the potential mechanisms underlying the projectâs impacts.
Materials and Methods
This study was an analysis of anonymized service evaluation data collected in the âKindness by Postâ (KBP) project in 2020. It used a mixed-methods single-group design and data from 289 participants. Changes in wellbeing, loneliness, sense of belonging and hope from baseline (12thâ14th February) to follow-up (26th Februaryâ2nd March) were analyzed using linear or multinomial logistic regression. Regression models also examined the associations between changes in wellbeing and baseline loneliness or participation level. Free text responses about experiences and suggestions for the project were analyzed using thematic analysis.
Results
Participants had a small, but statistically significant improvement, in wellbeing equating to 0.21 standard deviations (95% CI: 0.12â0.30) after taking part in the project, as well as improvements in loneliness, sense of belonging and hope. How lonely a participant was at baseline and whether participants both sent and received a kindness card were not associated with improvements in wellbeing. In the qualitative analysis, a desire to help others emerged as the main motivator to take part in the card exchange. Participants reported enhanced personal fulfillment, leading to improvements in wellbeing. Receiving a card could make people feel special and cherished, which was reported to establish a sense of connection with others, with potential benefits for reducing loneliness.
Conclusion
This study provided preliminary evidence that the KBP project might improve wellbeing, loneliness, sense of belonging and hope. Sending a kindness card in this project played a predominant role in wellbeing enhancement, and receiving a kindness card could reduce loneliness. This study suggests that the KBP project can be replicated in more contexts in the future, and might improve wellbeing and loneliness in large communities
Inorganic nitrate supplementation improves muscle oxygenation, O2 uptake kinetics and exercise tolerance at high but not low pedal rates
Copyright © 2014, Journal of Applied PhysiologyWe tested the hypothesis that inorganic nitrate (NO3-) supplementation would improve muscle oxygenation, pulmonary O2 uptake (VO2) kinetics and exercise tolerance (Tlim) to a greater extent when cycling at high compared low pedal rates. In a randomized, placebo-controlled, cross-over study, seven subjects (mean ± SD, age 21 ± 2 yr, body mass 86 ± 10 kg) completed severe-intensity step cycle tests at pedal cadences of 35 rpm and 115 rpm during separate 9 day supplementation periods with NO3--rich beetroot juice (BR; providing 8.4 mmol NO3-âday-1) and placebo (PLA). Compared to PLA, plasma nitrite concentration increased 178% with BR (P0.05). However, when cycling at 115 rpm, muscle [O2Hb] was higher at baseline and throughout exercise, phase II VO2 kinetics was faster (47 ± 16 s vs. 61 ± 25 s; P<0.05) and Tlim was greater (362 ± 137 s vs. 297 ± 79 s; P<0.05) with BR compared to PLA. These results suggest that short-term BR supplementation can increase muscle oxygenation, expedite the adjustment of oxidative metabolism and enhance exercise tolerance when cycling at a high, but not a low, pedal cadence in healthy recreationally-active subjects. These findings support recent observations that NO3- supplementation may be particularly effective at improving physiological and functional responses in type II muscle fibers
The evolution of ventral intermediate nucleus targeting in MRI-guided focused ultrasound thalamotomy for essential tremor: an international multi-center evaluation
© 2024 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Background: The ventral intermediate nucleus (VIM) is the premiere target in magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy for tremor; however, there is no consensus on the optimal coordinates for ablation. This study aims to ascertain the various international VIM targeting approaches (VIM-TA) and any evolution in practice. Methods: International MRgFUS centers were invited to share VIM-TAs in 2019 and 2021. Analyses of any modification in practice and of anatomical markers and/or tractography in use were carried out. Each VIM-TA was mapped in relation to the mid-commissural point onto a 3D thalamic nucleus model created from the SchaltenbrandâWahren atlas. Results: Of the 39 centers invited, 30 participated across the study period, providing VIM-TAs from 26 centers in 2019 and 23 in 2021. The results are reported as percentages of the number of participating centers in that year. In 2019 and 2021, respectively, 96.2% (n = 25) and 95.7% (n = 22) of centers based their targeting on anatomical landmarks rather than tractography. Increased adoption of tractography in clinical practice and/or for research was noted, changing from 34.6% to 78.3%. There was a statistically significant change in VIM-TAs in the superior-inferior plane across the study period; the percentage of VIM-TAs positioned 2 mm above the intercommissural line (ICL) increased from 16.0% in 2019 to 40.9% in 2021 (WRST, p < 0.05). This position is mapped at the center of VIM on the 3D thalamic model created based on the SchaltenbrandâWahren atlas. In contrast, the VIM-TA medial-lateral and anterior-posterior positions remained stable. In 2022, 63.3% of participating centers provided the rationale for their VIM-TAs and key demographics. The centers were more likely to target 2 mm above the ICL if they had increased experience (more than 100 treatments) and/or if they were North American. Conclusion: Across the study period, FUS centers have evolved their VIM targeting superiorly to target the center of the VIM (2 mm above the ICL) and increased the adoption of tractography to aid VIM localization. This phenomenon is observed across autonomous international centers, suggesting that it is a more optimal site for FUS thalamotomy in tremors.Peer reviewe
Vibration-tolerant narrow-linewidth semiconductor disk laser using novel frequency-stabilisation schemes
This paper will present developments in narrow-linewidth semiconductor-disk-laser systems using novel frequency-stabilisation schemes for reduced sensitivity to mechanical vibrations, a critical requirement for mobile applications. Narrow-linewidth single-frequency lasers are required for a range of applications including metrology and high-resolution spectroscopy. Stabilisation of the laser was achieved using a monolithic fibre-optic ring resonator with free spectral range of 181 MHz and finesse of 52 to act as passive reference cavity for the laser. Such a cavity can operate over a broad wavelength range and is immune to a wide band of vibrational frequency noise due to its monolithic implementation. The frequency noise of the locked system has been measured and compared to typical Fabry-Perot-locked lasers using vibration equipment to simulate harsh environments, and analysed here. Locked linewidths of < 40 kHz have been achieved. These developments offer a portable, narrow-linewidth laser system for harsh environments that can be flexibly designed for a range of applications
Processing and characterisation of II-VI ZnCdMgSe thin film gain structures
Lattice-matched II-VI selenide quantum well (QW) structures grown on InP substrates can be designed for emission throughout the visible spectrum. InP has, however, strong visible-light absorption, so that a method for epitaxial lift-off and transfer to transparent substrates is desirable for vertically-integrated devices. We have designed and grown, via molecular beam epitaxy, ZnCdSe/ZnCdMgSe multi-QW gain regions for vertical emission, with the QWs positioned for resonant periodic gain. The release of the 2.7 ÎŒm-thick ZnCdSe/ZnCdMgSe multi-QW film is achieved via selective wet etching of the substrate and buffer layers leaving only the epitaxial layers, which are subsequently transferred to transparent substrates, including glass and thermally-conductive diamond. Post-transfer properties are investigated, with power and temperature-dependent surface and edge-emitting photoluminescence measurements demonstrating no observable strain relaxation effects or significant shift in comparison to unprocessed samples. The temperature dependant quantum well emission shift is found experimentally to be 0.13 nm/K. Samples capillary-bonded epitaxial-side to glass exhibited a 6 nm redshift under optical pumping of up to 35 mW at 405 nm, corresponding to a 46 K temperature increase in the pumped region; whereas those bonded to diamond exhibited no shift in quantum well emission, and thus efficient transfer of the heat from the pumped region. Atomic force microscopy analysis of the etched surface reveals a root-mean-square roughness of 3.6 nm. High quality optical interfaces are required to establish a good thermal and optical contact for high power optically pumped laser applications
Assessing Novel Lidar Modalities for Maximizing Coverage of a Spaceborne System through the Use of Diode Lasers
Current satellite lidars have sparse spatial coverage, leading to uncertainty from sampling. This complicates robust change detection and does not allow applications that require continuous coverage. One potential way to increase lidar sampling density is to use more efficient lasers. All current spaceborne lidars use solid-state lasers with a limited efficiency of 5â8%. In this paper, we investigate the potential for using diode lasers, with their higher efficiencies, as an alternative. Diode lasers have reported efficiencies of about 25% and are much smaller and lighter than solid-state lasers. However, they can only emit good beam quality at lower peak powers, which has so far prevented them from being used in spaceborne lidar applications. In this paper, we assess whether the novel lidar modalities necessitated by these lower peak powers are suitable for satellite lidar, determined by whether they can match the design performance of GEDI by being able to accurately measure ground elevation through 98% canopy cover, referred to as having â98% beam sensitivityâ. Through this, we show that a diode laser can be operated in pulse train or pulse compressed lidar (PCL) mode from space, using a photon-counting detector. In the best case scenario, this setup requires a detected energy of Edet=0.027Â fJ to achieve a beam sensitivity of 98%, which is less than the 0.28 fJ required by a full-waveform solid-state lidar instrument, exemplified by GEDI. When also accounting for the higher laser and detector efficiency, the diode laser in pulse train mode requires similar shot energy as a photon counting solid-state laser such as ICESat-2 which along with the higher laser efficiency could result in a doubling of coverage. We conclude that there is a clear opportunity for diode lasers to be used in spaceborne lidars, potentially allowing wider coverage through their higher efficiencies
Illusions of SelfâMotion during Magnetic Resonance âGuided Focused Ultrasound Thalamotomy for Tremor
© 2024 The Authors. Annals of Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Objective: Brain networks mediating vestibular perception of selfâmotion overlap with those mediating balance. A systematic mapping of vestibular perceptual pathways in the thalamus may reveal new brain modulation targets for improving balance in neurological conditions. Methods: Here, we systematically report how magnetic resonanceâguided focused ultrasound surgery of the nucleus ventralis intermedius of the thalamus commonly evokes transient patientâreported illusions of selfâmotion. In 46 consecutive patients, we linked the descriptions of selfâmotion to sonication power and 3âdimensional (3D) coordinates of sonication targets. Target coordinates were normalized using a standard atlas, and a 3D model of the nucleus ventralis intermedius and adjacent structures was created to link sonication target to the illusion. Results: A total of 63% of patients reported illusions of selfâmotion, which were more likely with increased sonication power and with targets located more inferiorly along the rostrocaudal axis. Higher power and more inferiorly targeted sonications increased the likelihood of experiencing illusions of selfâmotion by 4 and 2 times, respectively (odds ratios = 4.03 for power, 2.098 for location). Interpretation: The phenomenon of magnetic vestibular stimulation is the most plausible explanation for these illusions of selfâmotion. Temporary unilateral modulation of vestibular pathways (via magnetic resonanceâguided focused ultrasound) unveils the central adaptation to the magnetic fieldâinduced peripheral vestibular bias, leading to an explicable illusion of motion. Consequently, systematic mapping of vestibular perceptual pathways via magnetic resonanceâguided focused ultrasound may reveal new intracerebral targets for improving balance in neurological conditions. ANN NEUROL 2024Peer reviewe
Crisis-focused Cognitive Behavioural Therapy for psychosis (CBTp) in acute mental health inpatient settings (the CRISIS study): protocol for a pilot randomised controlled trial
BACKGROUND: Cognitive Behavioural Therapy for psychosis (CBTp) has an established evidence base and is recommended by clinical guidelines to be offered during the acute phases of psychosis. However, few research studies have examined the efficacy of CBTp interventions specifically adapted for the acute mental health inpatient context with most research trials being conducted with white European community populations. AIMS: The aim of this study is to conduct a pilot randomised controlled trial (RCT), which incorporates the examination of feasibility markers, of a crisis-focused CBTp intervention adapted for an ethnically diverse acute mental health inpatient population, in preparation for a large-scale randomised controlled trial. The study will examine the feasibility of undertaking the trial, the acceptability and safety of the intervention and the suitability of chosen outcome measures. This will inform the planning of a future, fully powered RCT. METHODS: A single-site, parallel-group, pilot RCT will be conducted examining the intervention. Drawing on principles of coproduction, the intervention has been adapted in partnership with key stakeholders: service users with lived experience of psychosis and of inpatient care (including those from ethnic minority backgrounds), carers, multi-disciplinary inpatient clinicians and researchers. Sixty participants with experience of psychosis and in current receipt of acute mental health inpatient care will be recruited. Participants will be randomly allocated to either the crisis-focused CBTp intervention or treatment as usual (TAU). DISCUSSION: Findings of this pilot RCT will indicate whether a larger multi-site RCT is needed to investigate the efficacy of the intervention. If the initial results demonstrate that this trial is feasible and the intervention is acceptable, it will provide evidence that a full-scale effectiveness trial may be warranted. TRIAL REGISTRATION: This trial has been prospectively registered on the ISRCTN registry ( ISRCTN59055607 ) on the 18th of February 2021
The effect of dietary nitrate supplementation on the spatial heterogeneity of quadriceps deoxygenation during heavy-intensity cycling
This study investigated the influence of dietary inorganic nitrate (NO3-) supplementation on pulmonary O2 uptake ( o2) and muscle deoxyhemoglobin/myoglobin (i.e. deoxy[Hb+Mb]) kinetics during submaximal cycling exercise. In a randomized, placebo-controlled, cross-over study, eight healthy and physically active male subjects completed multiple step cycle tests at a work rate equivalent to 50% of the difference between the gas exchange threshold and peak o2 over separate 4-day supplementation periods with NO3--rich (BR; providing 8.4 mmol NO3-âday-1) and NO3--depleted (placebo; PLA) beetroot juice. Pulmonary o2 was measured breath-by-breath and time-resolved near-infrared spectroscopy was utilized to quantify absolute deoxy[Hb+Mb] and total[Hb+Mb] within the rectus femoris, vastus lateralis, and vastus medialis. There were no significant differences (P > 0.05) in the primary deoxy[Hb+Mb] mean response time or amplitude between the PLA and BR trials at each muscle site. BR significantly increased the mean (three-site) end-exercise deoxy[Hb+Mb] (PLA: 91 ± 9 vs. BR: 95 ± 12 ”M, P < 0.05), with a tendency to increase the mean (three-site) area under the curve for total(Hb+Mb) responses (PLA: 3650 ± 1188 vs. BR: 4467 ± 1315 ”M·s-1, P = 0.08). The o2 slow component reduction after BR supplementation (PLA: 0.27 ± 0.07 vs. BR: 0.23 ± 0.08 L·min-1, P = 0.07) correlated inversely with the mean increases in deoxy[Hb+Mb] and total[Hb+Mb] across the three muscle regions (r2 = 0.62 and 0.66, P < 0.05). Dietary NO3- supplementation increased O2 diffusive conductance across locomotor muscles in association with improved o2 dynamics during heavy-intensity cycling transitions
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