2,248 research outputs found
Study of the relative costs associated with delivering the Connexions Service in rural and urban areas
Studies on a sex pheromone in Stegobium paniceum (L.) (Coleoptera; Anobiidae)
The sex pheromone system of Stegobium paniceum (L.) was studied in the laboratory by means of live female assay experiments as well as extraction of the pheromone from females using solvent and volatilisation techniques. Female beetles were shown to attract only males, which were themselves attractive to neither sex. Female Stegobium were capable of controlled pheromone emission even when body content levels were high. Newly eclosed females contained small quantities of pheromone which reached maximum levels in 6 to 9-day-old insects. Very little emission occurred until females were 2.5-3.5 days old, after which maximum emission rates were reached rapidly between days 3 and 4, the age at which the first mature oocytes were found in the calyx of female ovaries. A series of dilutions of solvent pheromone extracts were bioassayed with males and a theoretical minimum threshold level of response extrapolated to 0.0004 female equivalents. By comparison with a "wild" strain of Stegobium it was suggested that mass rearing over a long period increased male sensitivity to the pheromone but lengthened the period necessary to reach maximum response levels after adult emergence. Mating slightly reduced female pheromone content, but pheromone emission fluctuated markedly after mating for reasons not fully understood. The number of eggs laid per female increased from about 1.5 to over 40 if copulation occurred. Male presence during oviposition increased the percentage of females producing eggs but decreased the number of eggs laid per female of those laying. This reflects decreased fertility of females with age. The antennal sensilla of Stegobium were surveyed by means of light and scanning electron microscopy. The main types present were trichoidea, basiconica, chaetica and coeloconica, and there was no apparent sexual dimorphism of sensilla numbers or distribution. Male antennectomy completely inhibited sex pheromone response and progressive removal of club segments increasingly diminished male response intensity
Overdiagnosis due to screening mammography for women aged 40 years and over
This is a protocol for a Cochrane Review. The objective was to assess the effect of screening mammography for breast cancer on overdiagnosis in women aged 40 years and older at average risk of breast cancer
Rare quantum metastable states in the strongly dispersive Jaynes-Cummings oscillator
We present evidence of metastable rare quantum-fluctuation switching for the
driven dissipative Jaynes-Cummings oscillator coupled to a zero-temperature
bath in the strongly dispersive regime. We show that single-atom complex
amplitude bistability is accompanied by the appearance of a low-amplitude
long-lived transient state, hereinafter called `dark state', having a
distribution with quasi-Poissonian statistics both for the coupled qubit and
cavity mode. We find that the dark state is linked to a spontaneous flipping of
the qubit state, detuning the cavity to a low-photon response. The appearance
of the dark state is correlated with the participation of the two metastable
states in the dispersive bistability, as evidenced by the solution of the
Master Equation and single quantum trajectories.Comment: Extensively revised text, 18 revised figures (16 in main and 2 in
appendix), 38(+1) references, appendi
Advanced Rio-Imaging Experiment in Scandinavia (ARIES): System specification and scientific goals
Public perceptions of changing the terminology for low-risk thyroid cancer: A qualitative focus group study
Objectives To investigate public perceptions of overdiagnosis and overtreatment in low-risk thyroid cancer and explore opinions regarding the proposed strategy to change the terminology of low-risk cancers. Design Qualitative study using focus groups that included a guided group discussion and presentation explaining thyroid cancer, overdiagnosis and overtreatment, and proposed communication strategies. Transcripts were analysed thematically. Setting Sydney, Australia. Participants Forty-seven men and women of various ages from a range of socioeconomic backgrounds with no personal history of thyroid cancer. Results Participants had low pre-existing general awareness of concepts of overdiagnosis and overtreatment and expressed concern regarding this new information in relation to thyroid cancer. Overall, participants understood why the strategy to change the terminology was being proposed and could see potential benefits including reducing the negative psychological impact and stigma associated with the term 'cancer'; however, many still had reservations about the strategy. The majority of the concerns were around their worry about the risk of further disease progression and that changing the terminology may create confusion and cause patients not to take the diagnosis and its associated managements seriously. Despite varied views towards the proposed strategy, there was a strong overarching desire for greater patient and public education around overdiagnosis and overtreatment in both thyroid cancer and cancer generally in order to complement any revised terminology and/or other mitigation strategies. Conclusions We found a strong and apparently widely held desire for more information surrounding the topic of overdiagnosis and overtreatment. Careful consideration of how to inform both the public and current patients about the implications of a change in terminology, including changes to patients' follow-up or treatments, would be needed if such a change were to go ahead
Urine glycosaminoglycans in congenital and acquired nephrotic syndrome
Urine glycosaminoglycans in congenital and acquired nephrotic syndrome. To evaluate the specificity of a raised heparan sulphate (HS) excretion previously reported in four children with congenital nephrotic syndrome (CNS), we measured the urinary excretion of HS and chondroitin sulphate (CS) in seven children with Finnish-type congenital nephrotic syndrome (CNSF), seven with diffuse mesangial sclerosis (DMS), nine with focal segmental glomerulosclerosis (FSGS), 14 with steroid-sensitive nephrotic syndrome of whom eight had a biopsy confirming minimal change histology (SSNS), and 17 controls. The urine HS/CS ratio in normal children had a median of 0.36 (observed range 0.21 to 0.68) and was independent of age. HS/CS ratio was significantly greater than controls in CNSF (median 0.80, range 0.43 to 1.28), DMS (median 0.81, range 0.49 to 1.13) and FSGS children (median 0.66, range 0.38 to 1.6), but was not in SSNS (median 0.44, range 0.28 to 0.70). There was a positive correlation between the HS/CS ratio and urine albumin excretion. High HS/CS ratios are not diagnostic of a particular histological variety of CNS
JOINT-SPECIFIC POWER PRODUCTION DURING SUBMAXIMAL AND MAXIMAL CYCLING
Cycle ergometry is commonly used to quantify muscular work and power, and to elicit perturbations to metabolic homeostasis for a broad range of physiological investigations. Separate authors have reported that knee extension dominates power production during submaximal cycling (SUBcyc; Ericson, 1988) and hip extension is the dominate action during maximal cycling (MAXcyc, Martin & Brown, 2009). Changes in joint-specific powers across broad ranges of net cycling powers within one group of cyclists have not been reported. Our purpose was to determine the extent to which ankle, knee, and hip joint actions produced power across a range of net cycling powers. Based on previous reports we hypothesized that relative contributions of knee extension power would decrease and relative knee flexion and hip extension powers would increase as net cycling power increase
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