Review of laser isotope separation of uranium hexafluoride.

There is continuing world-wide interest in the possibility of enriching uranium by a laser process which uses uranium hexafluoride. Since no actual commercial plant exists at present this review examines the key areas of related research. It concludes that such a process is feasible that it must employ an adiabatic cooling system with UF6 the minor constituent in a predominantly monatomic or diatomic carrier gas that the necessary infrared and/or ultraviolet-visible lasers are in a state of development bordering on the minimum required and that the economics of such a process appear highly promising

An Electrocorticographic Brain Interface in an Individual with Tetraplegia

Brain-computer interface (BCI) technology aims to help individuals with disability to control assistive devices and reanimate paralyzed limbs. Our study investigated the feasibility of an electrocorticography (ECoG)-based BCI system in an individual with tetraplegia caused by C4 level spinal cord injury. ECoG signals were recorded with a high-density 32-electrode grid over the hand and arm area of the left sensorimotor cortex. The participant was able to voluntarily activate his sensorimotor cortex using attempted movements, with distinct cortical activity patterns for different segments of the upper limb. Using only brain activity, the participant achieved robust control of 3D cursor movement. The ECoG grid was explanted 28 days post-implantation with no adverse effect. This study demonstrates that ECoG signals recorded from the sensorimotor cortex can be used for real-time device control in paralyzed individuals

Investigation into the dynamic visual acuity of skilled cricketers using a continuous motion task

BACKGROUND: Great demands are imposed upon the perceptual-motor system when undertaking ball-throwing and -hitting tasks including cricket. That is, performers must detect and resolve object details while on the move - something referred to as dynamic visual acuity (DVA). The present study aimed to investigate DVA in skilled cricketers and non-cricketers using a more immediate or real-time assessment. METHODS: Skilled cricketers and non-cricketers had to detect the presence of the gap within a Landolt-C ring as it moved horizontally or vertically, while progressively increasing the size until the participants registered a response. Measures were taken as the mean (dynamic) minimum angle of resolution of the object size at the moment that participants correctly responded to the gap. Objects would move at either a high, medium or low velocity. RESULTS: There was greater dynamic visual acuity in the skilled cricketers compared to non-cricketers (p < .05). There was a reduced negative influence of object velocity on dynamic visual acuity in the skilled cricketers compared to non-cricketers (p < .05). CONCLUSIONS: We suggest these findings contribute to the growing evidence surrounding DVA within ball-throwing and -hitting sports, while making some assertions as to the implications for the cricket performance setting

Thyratron-switched modular CO2 TEA laser for infrared photochemical studies.

A thyratron-switched ultraviolet pre-ionised CO2 TEA laser consisting of four modules connected in series has been designed and constructed. The laser can be operated in the TEM 00 mode and is able to produce 2.5 J per pulse. The design and operation of the laser as a tool for infrared studies is discussed together with an evaluation of the effect of operating parameters on output characteristics

High repetition rate Q-switched CO2 laser.

A rotating mirror Q-switched CO2 laser was designed and constructed for use as an excitation source in infrared fluorescence studies. Output power of 33 W was reached in the continuous wave (CW) mode. In the pulsed mode peak powers of 3 kW and pulse widths of 200 ns FWHM have been measured. The repetition rate may be varied between 275 and 1000 Hz and single line operation is selectable with a diffraction grating. The design is compact and economical. The laser has shown freedom from electrical noise and average power stability of the order of 1 per cent; it has operated reliably for more than 1000 hours with a minimum of maintenance

Evolving robotic surgery training and improving patient safety, with the integration of novel technologies

INTRODUCTION: Robot-assisted surgery is becoming increasingly adopted by multiple surgical specialties. There is evidence of inherent risks of utilising new technologies that are unfamiliar early in the learning curve. The development of standardised and validated training programmes is crucial to deliver safe introduction. In this review, we aim to evaluate the current evidence and opportunities to integrate novel technologies into modern digitalised robotic training curricula. METHODS: A systematic literature review of the current evidence for novel technologies in surgical training was conducted online and relevant publications and information were identified. Evaluation was made on how these technologies could further enable digitalisation of training. RESULTS: Overall, the quality of available studies was found to be low with current available evidence consisting largely of expert opinion, consensus statements and small qualitative studies. The review identified that there are several novel technologies already being utilised in robotic surgery training. There is also a trend towards standardised validated robotic training curricula. Currently, the majority of the validated curricula do not incorporate novel technologies and training is delivered with more traditional methods that includes centralisation of training services with wet laboratories that have access to cadavers and dedicated training robots. CONCLUSIONS: Improvements to training standards and understanding performance data have good potential to significantly lower complications in patients. Digitalisation automates data collection and brings data together for analysis. Machine learning has potential to develop automated performance feedback for trainees. Digitalised training aims to build on the current gold standards and to further improve the 'continuum of training' by integrating PBP training, 3D-printed models, telementoring, telemetry and machine learning

Skeletal muscle AMPK is not activated during 2 h of moderate intensity exercise at ~65% VO2peak in endurance trained men

Key points: AMP-activated protein kinase (AMPK) is considered a major regulator of skeletal muscle metabolism during exercise. However, we previously showed that, although AMPK activity increases by 8–10-fold during ∼120 min of exercise at ∼65% (Formula presented.) in untrained individuals, there is no increase in these individuals after only 10 days of exercise training (longitudinal study). In a cross-sectional study, we show that there is also a lack of activation of skeletal muscle AMPK during 120 min of cycling exercise at 65% (Formula presented.) in endurance-trained individuals. These findings indicate that AMPK is not an important regulator of exercise metabolism during 120 min of exercise at 65% (Formula presented.) in endurance trained men. It is important that more energy is directed towards examining other potential regulators of exercise metabolism. Abstract: AMP-activated protein kinase (AMPK) is considered a major regulator of skeletal muscle metabolism during exercise. Indeed, AMPK is activated during exercise and activation of AMPK by 5-aminoimidazole-4-carboxyamide-ribonucleoside (AICAR) increases skeletal muscle glucose uptake and fat oxidation. However, we have previously shown that, although AMPK activity increases by 8–10-fold during ∼120 min of exercise at ∼65% (Formula presented.) in untrained individuals, there is no increase in these individuals after only 10 days of exercise training (longitudinal study). In a cross-sectional study, we examined whether there is also a lack of activation of skeletal muscle AMPK during 120 min of cycling exercise at 65% (Formula presented.) in endurance-trained individuals. Eleven untrained (UT; (Formula presented.) = 37.9 ± 5.6 ml.kg−1 min−1) and seven endurance trained (ET; (Formula presented.) = 61.8 ± 2.2 ml.kg−1 min−1) males completed 120 min of cycling exercise at 66 ± 4% (Formula presented.) (UT: 100 ± 21 W; ET: 190 ± 15 W). Muscle biopsies were obtained at rest and following 30 and 120 min of exercise. Muscle glycogen was significantly (P &lt; 0.05) higher before exercise in ET and decreased similarly during exercise in the ET and UT individuals. Exercise significantly increased calculated skeletal muscle free AMP content and more so in the UT individuals. Exercise significantly (P &lt; 0.05) increased skeletal muscle AMPK α2 activity (4-fold), AMPK αThr172 phosphorylation (2-fold) and ACCβ Ser222 phosphorylation (2-fold) in the UT individuals but not in the ET individuals. These findings indicate that AMPK is not an important regulator of exercise metabolism during 120 min of exercise at 65% (Formula presented.) in endurance trained men

Impact of proctoring on success rates for percutaneous revascularisation of coronary chronic total occlusions.

OBJECTIVE: To assess the impact of proctoring for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in six UK centres. METHODS: We retrospectively analysed 587 CTO procedures from six UK centres and compared success rates of operators who had received proctorship with success rates of the same operators before proctorship (pre-proctored) and operators in the same institutions who had not been proctored (non-proctored). There were 232 patients in the pre-proctored/non-proctored group and 355 patients in the post-proctored group. Complexity was assessed by calculating the Japanese CTO (JCTO) score for each case. RESULTS: CTO PCI success was greater in the post-proctored compared with the pre-proctored/non-proctored group (77.5% vs 62.1%, p<0.0001). In more complex cases where JCTO≥2, the difference in success was greater (70.7% vs 49.5%, p=0.0003). After proctoring, there was an increase in CTO PCI activity in centres from 2.5% to 3.5%, p<0.0001 (as a proportion of total PCI), and the proportion of very difficult cases with JCTO score ≥3 increased from 15.3% (35/229) to 29.7% (105/354), p<0.0001. CONCLUSIONS: Proctoring resulted in an increase in procedural success for CTO PCI, an increase in complex CTO PCI and an increase in total CTO PCI activity. Proctoring may be a valuable way to improve access to CTO PCI and the likelihood of procedural success

Microstructural characterization of AISI 431 martensitic stainless steel laser-deposited coatings

High cooling rates during laser cladding of stainless steels may alter the microstructure and phase constitution of the claddings and consequently change their functional properties. In this research, solidification structures and solid state phase transformation products in single and multi layer AISI 431 martensitic stainless steel coatings deposited by laser cladding at different processing speeds are investigated by optical microscopy, Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), orientation imaging microscopy (OIM), ternary phase diagram, Schaeffler and TTT diagrams. The results of this study show how partitionless solidification and higher solidification rates alter the microstructure and phase constitution of martensitic stainless steel laser deposited coatings. In addition, it is shown that while different cladding speeds have no effect on austenite–martensite orientation relationship in the coatings, increasing the cladding speed has resulted in a reduction of hardness in deposited coatings which is in contrast to the common idea about obtaining higher hardness values at higher cladding speeds.