20,531 research outputs found
Anion–arene adducts: C–H hydrogen bonding, anion– interaction, and carbon bonding motifs
This article summarizes experimental and theoretical evidence for the existence of four distinct binding modes for complexes of anions with charge-neutral arenes. These include C–H hydrogen bonding and three motifs involving the arene– system—the noncovalent anion– interaction, weakly covalent interaction, and strongly covalent interaction
Eating disorders in the time of COVID-19.
We have all been stunned by the speed of this viral pandemic. At the time of writing, one fifth of the world is under lockdown. The main foci have been on the public health effort to contain the spread of the virus, and the care of individuals with acute infection. We, in eating disorders, must have a broader brief. Not only must we help care for those sufferers who contract COVID-19, we must also address the impact-psychological, financial and social - on those that do not. The peculiarities of COVID-19 and the reaction of the public and governments to it, have particular relevance for people living with an eating disorder and those who care for them
Community-based trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial.
BACKGROUND: Pelvic inflammatory disease (PID) is common and can lead to tubal factor infertility, ectopic pregnancy or chronic pelvic pain. Despite major UK government investment in the National Chlamydia Screening Programme, evidence of benefit remains controversial. The main aim of this trial was to investigate whether screening and treatment of chlamydial infection reduced the incidence of PID over 12 months. Secondary aims were to conduct exploratory studies of the role of bacterial vaginosis (BV) in the development of PID and of the natural history of chlamydial infection.
DESIGN: Randomised controlled trial with follow up after 12 months.
SETTING NON-HEALTHCARE: Common rooms and lecture theatres at 20 universities and further education colleges in Greater London.
PARTICIPANTS: 2500 sexually active female students were asked to complete a questionnaire on sexual health and provide self-administered vaginal swabs and smears.
INTERVENTION: Vaginal swabs from intervention women were tested for chlamydia by polymerase chain reaction (PCR) and those infected referred for treatment. Vaginal swabs from control women were stored and analysed after a year. Vaginal smears were Gram stained and analysed for BV.
MAIN OUTCOME MEASURE: Incidence of clinical PID over 12 months in intervention and control groups. Possible cases of PID will be identified from questionnaires and record searches. Confirmation of the diagnosis will be done by detailed review of medical records by three independent researchers blind to whether the woman is in intervention or control group. TRIAL REGISTRATION: Clinical Trials NCT 00115388
Detection of amblyopia utilizing generated retinal reflexes
Investigation confirmed that GRR images can be consistently obtained and that these images contain information required to detect the optical inequality of one eye compared to the fellow eye. Digital analyses, electro-optical analyses, and trained observers were used to evaluate the GRR images. Two and three dimensional plots were made from the digital analyses results. These plotted data greatly enhanced the GRR image content, and it was possible for nontrained observers to correctly identify normal vs abnormal ocular status by viewing the plots. Based upon the criteria of detecting equality or inequality of ocular status of a person's eyes, the trained observer correctly identified the ocular status of 90% of the 232 persons who participated in this program
Printed thermocouple devices
A novel process for the fabrication of thermocouples using thick-film techniques has been developed. Thermoelectric reactions of 22 μV/°C per couple have been observed which are comparable to those of conventional thermocouples.
This work outlines the potential for a rapid, lowcost, low temperature manufacturing solution for the production of electrical temperature sensors
Charge identification for spectral lines in nitrogen
Ion charge identification for spectral lines in nitrogen by beam foil light source techniqu
Tank tests to determine the effect of varying design parameters of planing-tail hulls II : effect of varying depth of step, angle of after- body keel, length of afterbody chine, and gross load
The second part of a series of tests made in Langley tank no. 2 to determine the effect of varying design parameters of planing-tail hulls is presented. Results are given to show the effects on resistance characteristics of varying angle of afterbody keel, depth of step, and length of afterbody chine. The effect of varying the gross load is shown for one configuration. The resistance characteristics of planing-tail hulls are compared with those of a conventional flying-boat hull. The forces on the forebody and afterbody of one configuration are compared with the forces on a conventional hull. Increasing the angle of afterbody keel had small effect on hump resistance and no effect on high-speed resistance but increased free-to-trim resistance at intermediate speeds. Increasing the depth of step increased hump resistance, had little effect on high-speed resistance, and increased free-to-trim resistance at intermediate speeds. Omitting the chines on the forward 25 percent of the afterbody had no appreciable effect on resistance. Omitting 70 percent of the chine length had almost no effect on maximum resistance but broadened the hump and increased spray around the afterbody. Load-resistance ratio at the hump decreased more rapidly with increasing load coefficient for the planing-tail hull than for the representative conventional hull, although the load-resistance ratio at the hump was greater for the planing-tail hull than for the conventional hull throughout the range of loads tested. At speeds higher than hump speed, load-resistance ratio for the planing-tail hull was a maximum at a particular gross load and was slightly less at heavier and lighter gross loads. The planing-tail hull was found to have lower resistance than the conventional hull at both the hump and at high speeds, but at intermediate speeds there was little difference. The lower hump resistance of the planing-tail hull was attributed to the ability of the afterbody to carry a greater percentage of the total load while maintaining a higher value of load-resistance ratio
Quantitative evaluation of multiband photographic techniques Final report
Quantitative evaluation of multiband photographic techniques using combination of black and white and color photo
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