Emotional intimacy power predicts different sexual experiences for men and women.

Those who are more emotionally invested in relationships have less power than their partners. Furthermore, less powerful individuals may attempt to equalize power imbalances by offering rewards to their partner and using sex and condom use as exchange resources. Australian young adults reported their condom use and pressured sex experiences in both romantic (n = 708) and casual (n = 118) relationships. Results showed that greater power (lower relative emotional investment) predicted more condom use among those wanting to use condoms. In casual relationships, an interaction with gender showed that women in particular used condoms more when they had more power. Power also interacted with gender for pressured sex and, unexpectedly, men who had more power experienced more pressured sex. The possibility that condom use and pressured sex have different meanings for men and women is explored.

Insecticide resistance profiles can be misleading in predicting the survival of Myzus persicae genotypes on potato crops following the application of different insecticide classes.

BACKGROUND: The accuracy of predicting the survival of insecticide-resistant aphids following the application of commonly used insecticides from the carbamate, the pyrethroid, a mix of the two or the neonicotinoid chemical classes was evaluated in a potato field in Scotland. Equal proportions of five genotypes of the peach-potato aphid, Myzus persicae (Sulzer), with none, resistance to dimethyl-carbamates, resistance to pyrethroids or combinations conferring resistance to both chemical classes were released into potato field plots. The insecticides were sprayed separately onto these plots, the aphid populations were analysed after 6-8 days and the process repeated. RESULTS: For each assessment after the three separate spray events, plots treated with the carbamate had 48, 147 and 28%, those treated with pyrethroid 53, 210 and 89%, those treated with carbamate/pyrethroid 28, 108 and 64% and those treated with neonicotinoid 43, 55 and 11% of the numbers of M. persicae by comparison with untreated controls. Only the proportions of surviving aphids from the genotype containing no insecticide resistance traits and the genotype containing elevated carboxylesterases matched ratios predicted from the selective advantage afforded by the resistance traits alone. Survival of aphids from the other three genotypes that carried 1-3 of the insecticide resistance traits differed from expectations in all cases, possibly owing to physiological differences, including their vulnerability to predators and hymenopterous parasitoids present at the site and/or their carrying unknown insecticide resistance mechanisms. CONCLUSION: Control strategies based on knowledge of the genetically determined insecticide resistance profile of an M. persicae population alone are insufficient. Hence, other important factors contributing to aphid survival under insecticide pressure need to be considered.

Improved characterisation of aortic tortuosity.

Tortuosity can be described as the variation in blood vessel curvature. Abnormal tortuosity is an important clinical indicator of various conditions. Despite considerable research, there has been very little agreement on an accurate, unique measure of this phenomenon for clinical applications. It has been demonstrated that a single value is insufficient to describe vessel tortuosity. In this work, the fast Fourier transform of the vessel's curvature as a measure of tortuosity is introduced. Spectral analysis of a suite of computed-simulated vessels, a phantom and clinical data is carried out. Observation of the acquired spectra permits detection of the local curvature variations. Spectral analysis of curvature provides a compact and graphic representation of tortuosity. This paper also describes two new highly automated MATLAB algorithms for obtaining the vessel centrelines: a heuristic image processing algorithm, and an algorithm based on the probabilistic Hough transform. We demonstrate the accuracy of both algorithms comparing with a manual method to extract the vessel centreline. Both algorithms reduce potential errors and user time and only require the manual selection of one centroid.

Deep brain stimulation can suppress pathological synchronisation in parkinsonian patients.

BACKGROUND: Although deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a highly effective therapeutic intervention in severe Parkinson's disease, its mechanism of action remains unclear. One possibility is that DBS suppresses local pathologically synchronised oscillatory activity. METHODS: To explore this, the authors recorded from DBS electrodes implanted in the STN of 16 patients with Parkinson's disease during simultaneous stimulation (pulse width 60 µs; frequency 130 Hz) of the same target using a specially designed amplifier. The authors analysed data from 25 sides. RESULTS: The authors found that DBS progressively suppressed peaks in local field potential activity at frequencies between 11 and 30 Hz as voltage was increased beyond a stimulation threshold of 1.5 V. Median peak power had fallen to 54% of baseline values by a stimulation intensity of 3.0 V. CONCLUSION: The findings suggest that DBS can suppress pathological 11-30 Hz activity in the vicinity of stimulation in patients with Parkinson's disease. This suppression occurs at stimulation voltages that are clinically effective.

The relationship between rejection sensitivity and compliant condom use.

Those who are rejection sensitive anxiously expect and readily perceive rejection. Rejection sensitivity is hypothesized to predict behavior; however, this link may be more evident in some contexts than others. The current study examined the link between rejection sensitivity and condom use. Australian young adults in romantic (n = 649, 70% female) and casual (n = 144, 76.2% female) relationship contexts completed measures on rejection sensitivity, condom use preferences, and condom use. Regression analysis showed that rejection sensitivity predicted condom use when participants' condom use preferences were at odds with those they thought their partner held. Specifically, highly rejection-sensitive individuals who preferred more frequent condom use reported using condoms less often, if that was what they thought their partners wanted. The results lend support to the model of rejection sensitivity in that individuals comply more with their perceived partner's preferences if they are more rejection-sensitive. The results also highlight the need to take the situational context into consideration when examining links between personality dispositions and behavior.

Women may underestimate their partners' desires to use condoms: possible implications for behaviour.

Australian young adults reported how often they wanted to use condoms in both romantic (n = 667) and casual relationship (n = 152) contexts and how often they thought their partners wanted to use condoms. Young adults wanted to use condoms more often than they perceived their partners to in both casual and romantic relationship contexts. Gender interactions showed that this pattern was especially strong among young women. Women seemed to underestimate the frequency at which their male partners wanted to use condoms. Furthermore, both the participants' condom use desires and perceptions of their partners' condom use desires predicted condom use behavior. Results suggest that gendered expectations may play a part in how often individuals perceive their partners to want to use condoms, which, in effect, may determine condom use behavior.

Tracking the global dispersal of a cosmopolitan insect pest, the peach potato aphid.

BACKGROUND: Global commerce and human transportation are responsible for the range expansion of various insect pests such as the plant sucking aphids. High resolution DNA markers provide the opportunity to examine the genetic structure of aphid populations, identify aphid genotypes and infer their evolutionary history and routes of expansion which is of value in developing management strategies. One of the most widespread aphid species is the peach-potato aphid Myzus persicae, which is considered as a serious pest on various crops in many parts of the world. The present study examined the genetic variation of this aphid at a world scale and then related this to distribution patterns. In particular, 197 aphid parthenogenetic lineages from around the world were analysed with six microsatellite loci. RESULTS: Bayesian clustering and admixture analysis split the aphid genotypes into three genetic clusters: European M. persicae persicae, New Zealand M. persicae persicae and Global M. persicae nicotianae. This partition was supported by FST and genetic distance analyses. The results showed two further points, a possible connection between genotypes found in the UK and New Zealand and globalization of nicotianae associated with colonisation of regions where tobacco is not cultivated. In addition, we report the presence of geographically widespread clones and for the first time the presence of a nicotianae genotype in the Old and New World. Lastly, heterozygote deficiency was detected in some sexual and asexual populations. CONCLUSION: The study revealed important genetic variation among the aphid populations we examined and this was partitioned according to region and host-plant. Clonal selection and gene flow between sexual and asexual lineages are important factors shaping the genetic structure of the aphid populations. In addition, the results reflected the globalization of two subspecies of M. persicae with successful clones being spread at various scales throughout the world. A subspecies appears to result from direct selection on tobacco plants. This information highlights the ultimate ability of a polyphagous aphid species to generate and maintain ecologically successful gene combinations through clonal propagation and the role of human transportation and global commerce for expanding their range.

Suppression of beta oscillations in the subthalamic nucleus following cortical stimulation in humans.

It is unclear how subthalamic nucleus activity is modulated by the cerebral cortex. Here we investigate the effect of transcranial magnetic stimulation (TMS) of the cortex on oscillatory subthalamic local field potential activity in the 8-35 Hz (alpha/beta) band, as exaggerated synchronization in this band is implicated in the pathophysiology of parkinsonism. We studied nine patients with Parkinson's disease (PD) to test whether cortical stimulation can modulate synchronized oscillations in the human subthalamic nucleus. With patients at rest, single-pulse TMS was delivered every 5 s over each primary motor area and supplementary motor area at intensities of 85-115% resting motor threshold. Subthalamic local field potentials were recorded from deep brain stimulation electrodes implanted into this nucleus for the treatment of PD. Motor cortical stimulation suppressed beta activity in the subthalamic nucleus from approximately 0.2 to 0.6 s after TMS (repeated measures anova; main effect of time, P < 0.01; main effect of side, P = 0.03), regardless of intensity. TMS over the supplementary motor area also reduced subthalamic beta activity at 95% (P = 0.05) and 115% resting motor threshold (P = 0.01). The oscillatory activity decreased to 80 +/- 26% of baseline (averaged across sites and stimulation intensities). Suppression with subthreshold stimuli confirmed that these changes were centrally driven and not due to peripheral afference. The results may have implications for mechanisms underlying the reported therapeutic benefits of cortical stimulation.

Gorlin's syndrome with associated odontogenic cysts.

Multiple maxillary and mandibular cysts are principle features of basal cell nevus syndrome (Gorlin-Goltz). We present cases from an affected family in which magnetic resonance imaging (MRI) was helpful in evaluation of the cystic lesions. A middle ear anomaly was identified which may represent an additional abnormality associated with the syndrome.

Relationships between ovarian morphology, vaginal cytology, serum progesterone, and urinary immunoreactive pregnanediol during the menstrual cycle of the cynomolgus monkey.

Three different indices of ovulation and luteal activity were studied in eight regularly cycling cynomolgus monkeys. A significant relation between changes in serum progesterone and immunoreactive pregnanediol (I-PD) in urine was obtained. The occurrence of ovulation could be determined reliably from a change in the ratio of cornified to basal epithelial cells in vaginal smears, and luteal activity could be assessed reliably from daily measurements of urinary pregnanediol. The time of ovulation could be defined more precisely by daily I-PD radioimmunoassays than by the vaginal smear pattern. Measurements of I-PD also have the advantage of ease and noninvasiveness over serum progesterone determinations. More detailed information about changes in hormonal activities could not be obtained reproducibly from thorough examination of cell types in vaginal smears.

Identification of a 17-hydroxyprogesterone-binding immunoglobulin in the serum of a woman with periodic rashes.

A 30-year-old patient with primary infertility had a history of recurrent oral and perineal rashes that appeared just prior to the midcycle rise in basal body temperature and subsided with the onset of menses. The rashes did not appear during periods of treatment with oral contraceptives or danazol, and were suppressed by administration of cortisol. Sera obtained during the follicular and luteal phases of her cycle were found to contain a progestin-binding component with high affinity for 17-hydroxyprogesterone and a somewhat lower affinity for progesterone. Analysis of these sera showed the progestin-binding component to have properties of IgG, with an apparent binding affinity for 17-hydroxyprogesterone of 2 X 10(10) M-1. This report is the first characterization of an antibody to an endogenous steroid in human serum.

Use of albumin gradients for X and Y sperm separation and clinical experience with male sex preselection.

Semen samples obtained from 18 normal males and 37 husbands requesting male child preselection were separated on concentration gradients of human serum albumin. Separated semen obtained from the husbands was then used for artificial homologous insemination (AIH). A significant increase in the sperm motility, progressive drive, and percentage of Y-bearing sperm along with a decrease in the total sperm count and percentage of abnormal forms were observed in separated specimens. Fathers of three or more female children had a slightly smaller but statistically significant percentage of Y-bearing sperm in their semen samples than did normal males. Ten conceptions were achieved with separated semen. Seven pregnancies terminated in normal deliveries of five male and two female infants, one ended in a spontaneous abortion of a male fetus, and two patients are still expecting. The ratio of male to female conceptions in this small study parallels the ratio of Y to X sperm in the final specimen used for AIH.

Artificial insemination homologous with oligospermic semen separated on albumin columns.

Semen samples obtained from 27 infertile men were separated on human serum albumin (HSA) columns prior to artificial homologous insemination (AIH). The columns contained either a single 7.5% HSA layer or two 17.5% and 7.5% HSA layers. Separated specimens were free of seminal debris, had significantly improved motility and progressive drive, and had a decreased percentage of abnormal forms. The total sperm count was also significantly decreased after separation, especially with the two-layer technique. No conceptions occurred in 21 couples when two-layer separation was used, but four pregnancies in 12 couples resulted from AIH with semen separated on the single-layer column. The mean total count of motile sperm obtained for AIH was 5 million with the two-layer and 31 million with the one-layer technique.

Who needs darkrooms?

With the advent of recent developments in film manufacturing and experience with photographic filters, the possibility that the traditional x-ray darkroom may no longer be necessary, has been raised. The authors present their experiments using various light filters and film and suggest that with the use of various combinations of lights, films and small tabletop film processors now on the market the darkroom is indeed no longer necessary. Consequently, the elimination of the expense and space for planning darkrooms in new facilities, or replacing them in existing facilities, is a feasible possibility at this time.