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The results of an earlier Dutch study on prostitutes' clients, interviewed face-to-face, were cross-validated by means of telephone interviews, which both guaranteed anonymity and produced a larger sample of respondents (n = 559). Depending on their preference and financial resources, they had visited different types of prostitution; but about half of them had restricted themselves to one type. Inconsistent use of condoms was reported by 14% of the clients who had had vaginal or anal intercourse. Condoms were most frequently used in clubs, brothels and window prostitution, and least often in street, home and escort prostitution; in the last two sorts especially not with regular prostitutes. Whether or not prostitutes came from non-Western countries had no influence on protective behaviour of these clients. The formation of networks between different sorts of prostitution, through unsafe sexual contacts in two or more sorts, involved only 3% of respondents. Thus, prostitution in The Netherlands should be seen as a number of sparsely-connected networks rather than as a single network. The formation of networks between prostitution and the population at large is made possible by the 10% of the respondents who had had unsafe contacts with both commercial and private partners. [ABSTRACT FROM AUTHOR]

We report responses from 559 clients of female prostitutes, with a view to determining to what extent previously identified factors play a part in condom use. To increase the response rate to advertisements in daily and weekly newspapers, interviews were held by phone. This procedure had the advantage of ensuring the anonymity many clients demanded. Of those clients having vaginal or anal contact (91%), 14% had not always used condoms in the previous year. Compared with consistent condom users, these men were less highly educated, had twice as many commercial contacts, and had more contacts with 'steady' prostitutes. They were either more emotionally motivated to visit prostitutes than were consistent condom users or exhibited a stronger need for sexual variation. They showed a more compulsive attitude toward visiting prostitutes, had a more negative attitude toward prostitution in general, evaluated condoms more negatively, had a higher personal efficacy to achieve unsafe contacts, and had a higher general risk assessment, commensurate with their behavior. Men with only safe contacts had either an intrinsic or an extrinsic motivation for condom use. Among extrinsically motivated men, their behavior change was more recent and had not yet taken root: They still envisioned unsafe commercial sex to be possible in the future. Education aimed at the small group of men practicing unsafe contacts will not easily and directly lead to behavior change. But these educational activities may support prostitutes to persist in (consistent) condom use, regardless of clients' pressure to do otherwise. [ABSTRACT FROM AUTHOR]

African mole-rats (Bathyergidae) are an intensively studied family of subterranean rodents including three highly social and three solitary genera. Although their phylogenetic interrelations are clear, genetic diversity and the number of species within each genus is much less certain. Among the solitary genera, Heliophobius and Georychus were for a long time considered as monotypic, but molecular studies demonstrated strong phylogeographic structure within each genus and proposed that they represent complexes of cryptic species. The present study re-evaluates their internal genetic/phylogenetic structure using a combination of methodological approaches. We generated datasets of one mitochondrial and six specifically selected nuclear markers as well as of a large number of double digest restriction site associated (ddRAD) loci and then applied species delimitation analyses based on the multispecies coalescent model or clustering on co-ancestry matrices. The population structure was largely congruent across all analyses, but the methods differed in their resolution scale when determining distinct gene pools. While the multispecies coalescent model distinguished five Georychus and between eleven to thirteen Heliophobius gene pools in both Sanger sequenced and ddRAD loci, two clustering algorithms revealed significantly finer or coarser structure in ddRAD based co-ancestry matrices. Tens of clusters were distinguished by fineRADstructure and one (in Georychus) or two clusters (in Heliophobius) by Infomap. The divergence dating of the bathyergid phylogeny estimated that diversification within both genera coincided with the onset of the Pleistocene and was likely driven by repeated large-scale climatic changes. Based on this updated genetic evidence, we suggest recognizing one species of Georychus and two species of Heliophobius, corresponding to a northern and southern major lineage, separated by the Eastern Arc Mountains. Yet, the final taxonomic revision should await integrated evidence stemming from e.g. morphological, ecological, or behavioral datasets., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Southern Africa has a diverse endemic scorpion fauna, but a paucity of information currently confounds conservation of the group. Phylogeographic approaches represent a useful tool to identify the patterns and processes which underpin scorpion diversity, but these studies are lacking for southern African species. Among southern African scorpions, the semi-lithophilous Opistophthalmus pallipes has strict habitat requirements, and a distribution historically subjected to profound environmental turnover. As such, the species offers a model system to investigate the interplay between intrinsic and extrinsic factors as drivers of diversity and endemism. To investigate spatial genetic patterns within O. pallipes and the possible drivers thereof, the current study combines mitochondrial DNA and ecological information under a phylogeographic approach. The species is characterized by several genetically discrete and divergent populations. The factors which shape these genetic patterns appear to be both intrinsically (ecological specificity) and extrinsically (landscape structure and ecogeographic conditions) influenced, with major divergences corresponding to periods of profound environmental changes. Taken together, the findings of this study provide evidence of spatial genetic isolation and genetic diversity within a stenotopic southern African scorpion species. These findings partly explain the staggering diversity and endemism in southern African scorpions, but further phylogeographic studies are necessary to propose conservation scenarios for this group.

Ensuring optical transparency over a wide spectral range of a window with a view into the tailpipe of the combustion engine, while it is exposed to the harsh environment of soot-containing exhaust gas, is an essential pre-requisite for introducing optical techniques for long-term monitoring of automotive emissions. Therefore, a regenerable window composed of an optically transparent polysilicon-carbide membrane with a diameter ranging from 100 µm up to 2000 µm has been fabricated in microelectromechanical systems (MEMS) technology. In the first operating mode, window transparency is periodically restored by pulsed heating of the membrane using an integrated resistor for heating to temperatures that result in oxidation of deposited soot (600-700 °C). In the second mode, the membrane is kept transparent by repelling soot particles using thermophoresis. The same integrated resistor is used to yield a temperature gradient by continuous moderate-temperature heating. Realized devices have been subjected to laboratory soot exposure experiments. Membrane temperatures exceeding 500 °C have been achieved without damage to the membrane. Moreover, heating of membranes to ΔT = 40 °C above gas temperature provides sufficient thermophoretic repulsion to prevent particle deposition and maintain transparency at high soot exposure, while non-heated identical membranes on the same die and at the same exposure are heavily contaminated.

Background: We review genealogical relationships, biogeographic patterns and broad historical drivers of speciation within the Bathyergidae, a group of endemic African rodents, as well as identify key taxa which need further research., Methods: We sourced comparable cytochrome b sequence data (comparable data available for all members for the Family) and geographic information for all six genera of the African subterranean rodent. This information was combined into the most comprehensive and geographically representative evolutionary study for the Bathyergidae to date., Results: Species richness within the Bathyergidae appears to be underestimated, with undescribed taxa in five of the six genera. Biogeographic patterns suggest large historical distributions, which were repeatedly fragmented by major landscape changes (especially rifting, uplift and drainage evolution) since the Miocene. Aside from vicariant events, other factors (ecological specialization, population-level responses and climatic change) may have been instrumental in driving divergences in the Bathyergidae. As such, adaptive differences may exist among both populations and species across their discrete ranges, driving independent evolutionary trajectories among taxa. In addition, highly fragmented distributions of divergent (and often relict) lineages indicates the possibility of narrow endemics restricted to diminishing suitable habitats. From this, it is clear that a systematic revision of the Bathyergidae is necessary; such a revision should include comprehensive sampling of all putative taxa, the addition of genomic information to assess adaptive differences, as well as ecological information., Competing Interests: The authors declare that they have no competing interests., (© 2019 Visser et al.)

The family Bathyergidae (comprising six genera) is a group of subterranean rodents endemic to sub-Saharan Africa. Our understanding of the evolution and species richness of the South African bathyergid genera Georychus, Bathyergus and Cryptomys is limited, with the majority of species listed as Least Concern by the IUCN Red List of Threatened Species. Genetic data suggest that several cryptic species may be present in these genera. To explore genetic and ecological distinctiveness, and evaluate taxonomic richness across the ranges of Georychus, Bathyergus and to a lesser degree, Cryptomys, as well as evaluate possible scenarios which have historically influenced evolutionary patterns, we employed four protein coding markers (one mitochondrial and three nuclear) along with distribution wide sampling schemes and large sample sizes. In addition, possible ecological differences among the different intra-generic clades were explored. Genera appear to have originated in the north-eastern interior of South Africa, following novel habitats created through the Post-African I erosion cycle and dramatic changes in climate and phytogeography. In each genus, multiple geographically discrete genetic lineages (clades) are supported by both the mitochondrial and nuclear data. These lineages bear signature of the fragmentation of wider historical distributions through major environmental changes since the middle Miocene (major uplift events, Post-African II erosion cycle, drainage evolution of major river systems, sea-level fluctuations as well as climatic changes and vegetation shifts), thereby leading to long-term isolation. Along with protracted periods of separation, it appears that ecological differences further delimit the lineages in relation to geology, phytogeographic preference, elevation, rainfall and temperature. As such, two lineages in Georychus (Clades 1 and 2) and one lineages in Cryptomys (Clade I) occur at higher elevations above the Great Escarpment (in older deposits harbouring grassland vegetation, with higher rainfall and lower daily temperatures), with the remaining lineages within these genera (Clades 3, 4 and 5 in Georychus and Clades III and IV in Cryptomys) occupying a low-land distribution with contrasting climatic and geological characteristics. Although significant differences in ecological variables were also observed between Bathyergus clades, these were not consistent, given their largely low-land distributions. Our results corroborate and expand previous suggestions that several cryptic species are present within the South African Bathyergidae., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The subterranean niche harbours animals with extreme adaptations. These adaptations decrease the vagility of taxa and, along with other behavioural adaptations, often result in isolated populations characterized by small effective population sizes, high inbreeding, population bottlenecks, genetic drift and consequently, high spatial genetic structure. Although information is available for some species, estimates of genetic diversity and whether this variation is spatially structured, is lacking for the Cape mole-rat (Georychus capensis). By adopting a range-wide sampling regime and employing two variable mitochondrial markers (cytochrome b and control region), we report on the effects that life-history, population demography and geographic barriers had in shaping genetic variation and population genetic patterns in G. capensis. We also compare our results to information available for the sister taxon of the study species, Bathyergus suillus. Our results show that Georychus capensis exhibits low genetic diversity relative to the concomitantly distributed B. suillus, most likely due to differences in habitat specificity, habitat fragmentation and historical population declines. In addition, the isolated nature of G. capensis populations and low levels of population connectivity has led to small effective population sizes and genetic differentiation, possibly aided by genetic drift. Not surprisingly therefore, G. capensis exhibits pronounced spatial structure across its range in South Africa. Along with geographic distance and demography, other factors shaping the genetic structure of G. capensis include the historical and contemporary impacts of mountains, rivers, sea-level fluctuations and elevation. Given the isolation and differentiation among G. capensis populations, the monotypic genus Georychus may represent a species complex.

The distribution of genetic variation is determined through the interaction of life history, morphology and habitat specificity of a species in conjunction with landscape structure. While numerous studies have investigated this interplay of factors in species inhabiting aquatic, riverine, terrestrial, arboreal and saxicolous systems, the fossorial system has remained largely unexplored. In this study we attempt to elucidate the impacts of a subterranean lifestyle coupled with a heterogeneous landscape on genetic partitioning by using a subterranean mammal species, the Cape dune mole-rat (Bathyergus suillus), as our model. Bathyergus suillus is one of a few mammal species endemic to the Cape Floristic Region (CFR) of the Western Cape of South Africa. Its distribution is fragmented by rivers and mountains; both geographic phenomena that may act as geographical barriers to gene-flow. Using two mitochondrial fragments (cytochrome b and control region) as well as nine microsatellite loci, we determined the phylogeographic structure and gene-flow patterns at two different spatial scales (local and regional). Furthermore, we investigated genetic differentiation between populations and applied Bayesian clustering and assignment approaches to our data. Nearly every population formed a genetically unique entity with significant genetic structure evident across geographic barriers such as rivers (Berg, Verlorenvlei, Breede and Gourits Rivers), mountains (Piketberg and Hottentots Holland Mountains) and with geographic distance at both spatial scales. Surprisingly, B. suillus was found to be paraphyletic with respect to its sister species, B. janetta-a result largely overlooked by previous studies on these taxa. A systematic revision of the genus Bathyergus is therefore necessary. This study provides a valuable insight into how the biology, life-history and habitat specificity of animals inhabiting a fossorial system may act in concert with the structure of the surrounding landscape to influence genetic distinctiveness and ultimately speciation.

Objectives: The purpose of the study was to identify and understand social media usage behaviour of dentists in South Africa, in general and in particular as part of their marketing strategy and to consider the potential determinants associated with these behaviours., Methods: Dentists who are members of the South African Dental Association were requested to anonymously complete an online questionnaire. Apart from demographic information, respondents were asked to report on their use of social media and their adoption of social media marketing. One-on-one interviews were also conducted with three dentists, to gain a deeper understanding of their adoption of this marketing option., Results: South African dentists have started to embrace social media and 50.2% interact through these channels at least once a day. The most popular social media platforms are GooglePlus and Facebook. Respondents use social media mainly for personal purposes, including staying connected to family and friends.. Only 13.2% of those responding currently use social media as a marketing tool, but the majority (83.5%) predict that such usage will increase in future., Conclusion: Social media marketing is a growing trend and will become more significant in future. Although respondents used social media regularly for personal purposes, most are only now starting to use it as a marketing tool.

A long-term experiment on the effect of chitin addition to soil on the suppression of soilborne pathogens was set up and monitored for 8 years in an experimental field, Vredepeel, The Netherlands. Chitinous matter obtained from shrimps was added to soil top layers on two different occasions, and the suppressiveness of soil toward Verticillium dahliae, as well as plant-pathogenic nematodes, was assessed, in addition to analyses of the abundances and community structures of members of the soil microbiota. The data revealed that chitin amendment had raised the suppressiveness of soil, in particular toward Verticillium dahliae, 9 months after the (second) treatment, extending to 2 years following treatment. Moreover, major effects of the added chitin on the soil microbial communities were detected. First, shifts in both the abundances and structures of the chitin-treated soil microbial communities, both of total soil bacteria and fungi, were found. In addition, the abundances and structures of soil actinobacteria and the Oxalobacteraceae were affected by chitin. At the functional gene level, the abundance of specific (family-18 glycoside hydrolase) chitinase genes carried by the soil bacteria also revealed upshifts as a result of the added chitin. The effects of chitin noted for the Oxalobacteraceae were specifically related to significant upshifts in the abundances of the species Duganella violaceinigra and Massilia plicata. These effects of chitin persisted over the time of the experiment.

An impedimetric NOx dosimeter based on the NOx sorption material KMnO4 is proposed. In addition to its application as a low level NOx dosimeter, KMnO4 shows potential as a precious metal free lean NOx trap material (LNT) for NOx storage catalysts (NSC) enabling electrical in-situ diagnostics. With this dosimeter, low levels of NO and NO2 exposure can be detected electrically as instantaneous values at 380 °C by progressive NOx accumulation in the KMnO4 based sensitive layer. The linear NOx sensing characteristics are recovered periodically by heating to 650 °C or switching to rich atmospheres. Further insight into the NOx sorption-dependent conductivity of the KMnO4-based material is obtained by the novel eTPD method that combines electrical characterization with classical temperature programmed desorption (TPD). The NOx loading amount increases proportionally to the NOx exposure time at sorption temperature. The cumulated NOx exposure, as well as the corresponding NOx loading state, can be detected linearly by electrical means in two modes: (1) time-continuously during the sorption interval including NOx concentration information from the signal derivative or (2) during the short-term thermal NOx release.

The accumulating-type (or integrating-type) NO(x) sensor principle offers two operation modes to measure low levels of NO(x): The direct signal gives the total amount dosed over a time interval and its derivative the instantaneous concentration. With a linear sensor response, no baseline drift, and both response times and recovery times in the range of the gas exchange time of the test bench (5 to 7 s), the integrating sensor is well suited to reliably detect low levels of NO(x). Experimental results are presented demonstrating the sensor's integrating properties for the total amount detection and its sensitivity to both NO and to NO(2). We also show the correlation between the derivative of the sensor signal and the known gas concentration. The long-term detection of NO(x) in the sub-ppm range (e.g., for air quality measurements) is discussed. Additionally, a self-adaption of the measurement range taking advantage of the temperature dependency of the sensitivity is addressed.

The red bud borer Resseliella oculiperda (Rübs.) is a pest insect of apple trees when rootstocks are grafted with scion buds by 'shield budding'. The female midges are attracted to the wounds of the grafted buds where they lay their eggs. The larvae feed on the cambium and destroy the buds completely or partially, leading to bad union of the buds with the rootstocks. Budding strips are used very often by growers to bind scion buds to rootstocks. These strips cannot prevent midges from reaching the damaged tissue. Chemical treatments applied to the grafts and other types of strip do not provide better protection against the pest and may cause other risks for growers. In orchard experiments in 2000 and 2001, the authors evaluated the repellent action provided by three essential oils and five compounds of plant origin against the midges by impregnating budding strips with them. The essential oils of lavender, Lavandula angustifolia (P. Mill.), and alpha-terpineol decreased the infestation of buds by more than 95 and 80% respectively. The other potential repellents tested [the essential oil of Juniperus virginiana (L.), citronellal, the essential oil of Cinnamomum camphora (L.) J. Presl, R-carvone, linalool and R-fenchone] decreased infestation by 67, 66, 51, 45, 37 and 25% respectively. The formulation and commercial development of budding strips impregnated with lavender oil is discussed.

Objective: To compare the predictive validity of the clinical-diagnostic and the empirical-quantitative approach to assessment of childhood psychopathology, and to investigate the usefulness of combining both approaches., Method: A referred sample (N = 96), aged 6 to 12 years at initial assessment, was followed up across--on average--a period of 3.2 years. It was assessed to what extent DISC/DSM-III-R diagnoses--representing the clinical-diagnostic approach, and CBCL scores--representing the empirical-quantitative approach, predicted the following signs of poor outcome: outpatient/inpatient treatment, or parents' wish for professional help for the child at follow-up, disciplinary problems in school, and police/judicial contacts., Results: Both diagnostic systems added significantly to the prediction of poor outcome, and neither of the two systems was superior. Use of both systems simultaneously provided the most accurate estimation of the prognosis, reflected by the occurrence of future poor outcome. Even diagnostic concepts that are generally regarded as relatively similar, such as ADHD (DSM) and attention problems (CBCL), or conduct disorder (DSM) and delinquent behavior (CBCL), appeared to differ in their ability to predict poor outcome., Conclusions: The present study supports the use of the empirical-quantitative approach and the clinical-diagnostic approach simultaneously, both in research and in clinical settings, to obtain a comprehensive view of the prognosis of psychopathology in children.

Background: The present study investigated the differential predictive value of parents', teachers', and clinicians' reports of psychopathology for poor outcome in children referred to a child psychiatric outpatient clinic., Method: A referred sample (N = 96), aged 6 to 12 years at initial assessment, was followed up after a mean interval of 3.2 years. Data on parent- and teacher-reported problem behavior (Child Behavior Checklist and Teacher's Report Form), and clinician-reported observations and self-reports during a semi-structured clinical interview (SCICA), were linked to outcome measures assessed with a parent questionnaire, including outpatient and inpatient treatment at Time 2, parent's wish for professional help for the child, school problems, and police/judicial contacts., Results: Information from all three informants (clinicians, parents, and teachers) predicted measures of poor outcome after three years. Clinicians' ratings on the SCICA predicted all five outcome measures. Independent of CBCL and TRF scores, SCICA scores predicted parental wish for help and inpatient treatment., Conclusions: The present study was the first to report that clinician's ratings of self-reported and observed behaviors in a semi-structured interview (SCICA) make an important unique contribution to the multiaxial assessment of problem behaviors.

Background: Little evidence is available on factors associated with persistence and change of psychopathology, and little is known about the predictive value of factors regarding change once problem behaviours exist. This study aims to evaluate change in level of scores of empirically derived problem patterns and to study factors that influence this change for children and adolescents referred to mental health services., Method: A referred sample (N = 1,652), aged 4 to 18 years at initial assessment, was followed up after a mean interval of 6.2 years. We used standardised information from parents, teachers and subjects, including the CBCL, YSR and TRF at both assessments., Results: Subjects at follow-up scored significantly above the expected mean norm scores, although for most scores improvement was found. The strongest predicting factor for time 2 psychopathology was the corresponding time 1 score, odds ratios ranging from 1.6 to 21.7. Males and children older at intake improved more than females and younger children, respectively., Conclusions: Few child, family and treatment-related factors had additional predictive value over and above earlier psychopathology, and their contribution to the prediction of outcome was small. Findings indicate continuity of behavioural and emotional problems in clinically referred children and adolescents, and these problems should be viewed as chronic conditions. Girls referred for behavioural and emotional problems may form a group especially at risk for poor outcome.

Attenuation in a gas results from a combination of classical attenuation, attenuation from diffusion, and attenuation due to molecular relaxation. In previous papers [J. Acoust. Soc. Am. 109, 1955 (2001); 110, 2974 (2001)] a model is described that predicts the attenuation from vibrational relaxation in gas mixtures. In order to validate this model, the attenuation was measured using a pulse technique with four transducer pairs, each with a different resonant frequency. The attenuation calculated using the model was compared to the measured values for a variety of gases including: air, oxygen, methane, hydrogen, and mixtures of oxygen/nitrogen, methane/nitrogen, carbon dioxide/nitrogen, and hydrogen/nitrogen. After the measured data is corrected for diffraction, the model matches the trends in the measured attenuation spectrum for this extensive set of gas mixtures., (c2003 Acoustical Society of America.)

The product of the percentage blasts on the bone marrow aspirate (BMA) and the biopsy cellularity has been termed the "absolute blast index aspirate" (ABI-aspirate) and is used to measure disease response on day 7 of induction therapy. The authors compared the event-free survival (EFS) in high-risk and standard-risk patients as identified by the ABI-aspirate and the BMA percentage blasts on day 14 of induction therapy. Both indices identified high-risk cases. EFS of patients categorized as high-risk by these 2 methods and the high-risk criteria used by the authors' service (WCC of > 20 x 10(9)/L, age < 2 and > 8 years and a peripheral blood blast count of > 1.0 x 10(9)/L on day 8 of induction) did not differ. There was concordance between patients identified as high risk by all 3 methods. The results confirmed the prognostic value of the ABI-aspirate and the BMA percentage blasts on day 14 of induction therapy, but these methods were not superior to the high-risk criteria currently in use.

Background: For children referred to mental health services future functioning may be hampered., Aims: To examine stability and prediction of behavioural and emotional problems from childhood into adulthood., Method: A referred sample (n = 789) aged 4-18 years was followed up after a mean of 10.5 years. Scores derived from the Child Behavior Checklist, Youth Self-Report and Teacher Report Form were related to equivalent scores for young adults from the Young Adult Self-Report and Young Adult Behavior Checklist., Results: Correlations between first contact (T1) and follow-up (T2) scores were 0.12-0.53. Young adult psychopathology was predicted by corresponding T1 problem scores. Social problems and anxious/depressed scores were predictors of general problem behaviour., Conclusions: Problem behaviour of children and adolescents referred to outpatient mental health services is highly predictive of similar problem behaviour at young adulthood. Stability is higher for externalizing than for internalizing behaviour and for intra-informant than for inter-informant information. Stabilities are similar across gender. To obtain a comprehensive picture of the young adult's functioning, information from related adults may prove valuable.

Objective: To investigate the stability and predictive strength of behavioral and emotional problems in childhood and adolescence., Method: A referred sample (N = 1,652), aged 4 to 18 years at initial assessment, was followed up after a mean interval of 6.2 years. Problem scores derived from Child Behavior Checklist, Youth Self-Report, and Teacher's Report Form at initial assessment (T1) were related to scores on the same instruments at follow-up (T2)., Results: Correlations between T1 and corresponding T2 problem scores averaged 0.41 intrainformant (range 0.22-0.61) and 0.22 interinformant (range -0.09-0.57). Stabilities were similar across gender, and larger for Externalizing versus Internalizing scores, except on youths' self-reports. Psychopathology scores at follow-up were predicted by corresponding T1 scores. Girls were predicted to have higher T2 Somatic Complaints, Anxious/Depressed, Thought Problems, and Internalizing scores than boys. Children younger at intake were predicted to have higher scores than older children on T2 Social and Attention Problems., Conclusions: Findings indicate continuity of specific behavioral and emotional problems in clinically referred children and adolescents.

The characterization of a gene with a unique microspore-specific expression pattern is reported. Isolated microspores from tobacco were used to synthesize a cDNA library. Clones that did not hybridize to leaf cDNA were further characterized by northern analysis. One clone proved to be a microspore-specific cDNA, representing a transcript of 650 nt. The corresponding gene, NTM19 (Nicotiana tabacum microspore-specific), was isolated and its sequence analysed. The gene encodes a protein of 10.8 kDa with a pI of 6.92 and a putative signal sequence at the N-terminus. A localization study revealed a unique spatial and temporal distribution. The transcript was only detected in the unicellular microspore. No hybridization signals were observed in other pollen developmental stages, nor in the surrounding anther tissues or other vegetative tissues of the plant. Therefore it can be concluded that NTM19 is a gene with a highly microspore-specific character according to both localization and stage of expression. Southern blot analysis demonstrated the presence of a small gene family. The occurrence of TNM19 was investigated in a range of closely and distantly related species and was found to be present in other solanaceous species, including the ancestors of tobacco and in a monocot species.

The sex pheromone of the South American potato tuber mothSymmetrischema tangolias (syn.:Symmetrischema plaesiosema) was identified as a 2:1 mixture of (E,Z)-3,7-tetradecadien-1-ol acetate and (E)-3-tetradecen-1-ol acetate by means of dual-column GC, EAG, GC-EAD, GC-MS, NMR, and wind-tunnel bioassays. (Z)-5-Tetradecen-1-ol acetate and (Z)-7-tetradecen-1-ol acetate were also identified in the pheromone gland extract. MaleS. tangolias were able to detect these acetates (EAG), but their addition to the two-component sex pheromone did not improve attractiveness. Field trials in Cajamarca and Cusco, Peru, showed that traps baited with the synthetic sex pheromone were able to catch large numbers of maleS. tangolias.

Professional HIV risk taking (nonconsistent condom use with clients) of female prostitutes in The Netherlands is addressed within the context of (early) experiences with abuse, well-being, coping behavior, job satisfaction, and financial need. Data were gathered from 127 female prostitutes on condom use, financial need, and professional attitude, and on experiences with violence and abuse, physical complaints, psychosocial problems, and coping responses. Violent traumatic experiences were found to relate to more severe complaints and problems, and a higher frequency of emotion-focused coping strategies. A risk-taking protection style (as opposed to consistent condom use and selective risk taking) appeared to be associated with more severe experiences with violence, both in childhood and in adult life, with more frequent dissociation as a coping behavior, and with more psychosomatic complaints. Of all the relationships found, more severe experiences with violence on the job were most strongly related to a higher professional HIV risk.

To investigate the hormonal control of gubernacular development and testicular descent we determined the effect of gonadal extracts and various hormones on the proliferation of gubernaculum cell cultures established from 55 male pig fetuses obtained at 60 to 90 days' gestation. The percentage of descended testes was 0 at 60, 8% at 70, 40% at 80 and 87% at 90 days' gestation. Significant proliferation (as measured by [3H]thymidine incorporation) of gubernaculum, but not 3T3, cells was induced by crude testicular but not ovarian extracts, and was directly related to its protein concentration. Significant proliferation of gubernaculum cells was induced by low molecular mass (< 30 kD) testicular, but not by high molecular mass (> 30 kD), testicular and low or high molecular mass ovarian extracts obtained by centrifugation of crude extracts in microspin filter membranes with a molecular cut-off mass of 30 kD. Proliferation of gubernaculum cells induced by the low molecular mass (<30 kD) testicular extract was significantly greater than that stimulated by testosterone or dihydrotestosterone. Polyacrylamide gel electrophoresis demonstrated a unique protein band at approximately 26 kD in the crude and low molecular mass testicular, but not in the ovarian, extracts. It is possible that this represents a novel peptide hormone secreted by the fetal testis, responsible for stimulating the growth of the gubernaculum, thereby mediating testicular descent.

To assess the prevalence and effects of alcohol and drug use in heterosexual and homosexual commercial contacts, and the relationship between their use and unsafe sexual behaviour, 127 female prostitutes, 27 male prostitutes, 91 clients of female prostitutes and 24 clients of male prostitutes were interviewed face-to-face with the help of a semi-structured questionnaire. The respondents were living or working in different parts of The Netherlands. Alcohol and drug use was found to be relatively common among prostitutes. This was also so for the use of alcohol by clients, though to a lesser extent. Prostitutes' consumption varied widely according to the type of prostitution they were employed in. Those meeting their clients in clubs or bars reported the highest consumption of alcohol; hard drugs were used predominantly by street prostitutes. It appears that the main effects of alcohol and drug use are on how the individual experiences working as, or calling on, a prostitute, the social interaction between the two parties, and the sexual contact itself. The common assumption that drinking alcohol has negative effects on condom use was not borne out; though female prostitutes working under the influence of drugs were significantly more likely to report unsafe sex. The degree to which commercial partners were judged to be under the influence of alcohol or drugs was not found to bear upon the frequency of respondents' condom use. For those prostitutes who use hard drugs, this use plays an important role in their engaging in unsafe sexual activities. Prevention activities should focus especially on this group, and should take into account the role of such drug use.

Twenty-seven male prostitutes were interviewed extensively about their work and considerations relating to safe sex with clients. Important differences were found between street prostitutes and those working at home. Street-workers were more likely to be using hard drugs, to have a heterosexual preference, to have no other occupation, to have more clients, but less steady ones, and to have a more negative working attitude. Sexual techniques most often practised were manual and oral contact; however, most prostitutes also practised either insertive or receptive anal intercourse. Homosexual male prostitutes reported more receptive anal intercourse than did their heterosexual male colleagues; but no such differences were found in insertive anal intercourse. Prostitutes were most likely to have had anal intercourse with steady clients, with clients whom they trusted regarding condom use, or with clients they felt sexually attracted to; and also when in dire need of drugs. Of those who had practised anal intercourse in the previous year, a minority had not consistently used condoms. The same factors that encourage anal intercourse also appear conducive to unprotected intercourse.

The role of the alkyl terminus of green leaf volatile (GLV) molecules in olfactory reception and inactivation was examined in three diverse insect species: the beet armyworm,Spodoptera exigua (Lepidoptera); the Colorado potato beetle,Leptinotarsa decemlineata (Coleoptera); and the desert locust,Schistocerca gregaria (Orthoptera), using selectively fluorinated analogs of GLVs and electroantennograms (EAGs). When only the magnitude of the depolarization of the EAG is considered (a measure of reception), the order of effectiveness was 1-hexanol (6:OH)=(Z)-3-6:OH > 5,5,6,6,6-pentafluoro-(Z)-3-6:OH =5,5-difluoro-(Z)-3-6:OH ≫ 5,5,6,6,6-pentafluoro-6: OH. Percent recovery of the EAG (a measure of inactivation) was greater for the pentafluoro-(Z)-3-6: OH analog than for the difluoro-(Z)-3-6: OH analog. Our results show that the alkyl end of GLV molecules plays an important role not only in reception, but also inactivation processes in insect olfaction. Furthermore, specificities of these two processes may differ.

Objectives: To assess the extent to which condoms are used effectively in commercial heterosexual intercourse. Data on the number of condoms that had broken or slipped off, the sexual technique during which this had occurred and the perceived cause of failure were collected. The use of non-water-soluble lubricants and non-fortified condoms during anal intercourse, and the demand for a greater variety of condom sizes were also examined., Subjects and Methods: One hundred and twenty-seven female prostitutes and 91 male clients from different parts of The Netherlands were interviewed face-to-face between July 1990 and March 1991., Results: Of those who used condoms during vaginal intercourse, 49% of the prostitutes had experienced condom breakage in the previous 6 months, and 16% of the clients in the previous 12 months. The breakage rate was 0.8% for prostitutes and 1.5% for clients. Condom quality was seldom reported as the cause; breakage was generally attributed to human factors, such as rough or prolonged intercourse, incorrect handling of the condom or the use of insufficient lubricant. Prostitutes also identified penis size as a cause. Condoms slipping off before or after ejaculation was reported less frequently than breakage. Thirteen per cent of clients and 36% of prostitutes expressed a need for either smaller or larger condoms. Of the prostitutes, 9% used oil or vaseline as a lubricant., Conclusions: In view of the low rate of condom failure in heterosexual prostitution in The Netherlands, the potential spread of HIV by this means is small. The use of a greater variety of condom sizes may further reduce the failure rate. Few prostitutes remain ignorant about the adverse effects of oil-based lubricants on condoms.

Information processing in the olfactory pathway underlying the perception of semiochemicals by insects is discussed. Both the chemical message for mates and the message for food consist of blends of chemicals. Olfactory receptors in an insect species are tuned to the detection of those compounds which comprise such chemical messages for that species. The classification of receptors as specialists or generalists coincides with two concepts of information processing, i.e., labeled lines and across-fiber patterns, respectively. The olfactory code coming from antennal receptors inPieris brassicae larvae is a combination of labeled lines and across-fiber patterning. When antennae of adult Colorado potato beetles,Leptinotarsa decemlineata, are stimulated by binary mixtures of leaf odor components, the pattern of neural activities in the olfactory receptors shows some separation into two channels, quantitative versus qualitative detection. The separation is complete in the antennal lobe of this beetle.

1. The solitary wasp Ampulex compressa stings a cockroach, Periplaneta americana, twice. 2. The first sting into the ventral thorax results in a transient paralysis. During this paralysis the wasp stings the suboesophageal ganglion, which gradually results in a permanent deactivation. 3. The venom gland is a paired and highly branched organ, with a common ductus venatus. The large lumen is lined with a folded cuticula. No venom reservoir is present. 4. Extract of the venom gland induces a slow contraction of the guinea pig ileum. 5. The agonist present in the venom cannot be identified with a known agonist. 6. Venom gland extract blocks synaptic transmission from the cercal nerve to giant neurons in the sixth abdominal ganglion of the cockroach. 7. The block develops gradually, like the gradual appearance of the effects of the sting into the suboesophageal ganglion on the behaviour of the cockroach.

Walking tracks of Colorado potato beetles,Leptinotarsa decemlineata Say, were recorded on a locomotion-compensator in response to wind, odors of host plantsSolanum tuberosum L. and nonhost plantsLycopersicon hirsutum f.glabratum C.H. Mull, and to mixtures of these plant species. Host-plant odor induced positive anemotactic responses in starved females, whereas odor of the nonhostL. hirsutum was neither repellent nor attractive. The attractiveness of host-plant odor, however, was neutralized in the odor blend of plant species. Masking the attractive host-plant odor will hinder the beetle's searching for host-plant patches, and this principle may be exploited in pest control by mixed cropping.

The processing of olfactory information in the Colorado potato beetle, Leptinotarsa decemlineata Say, was studied by recording responses of olfactory neurones intracellularly in the deutocerebrum. Response characteristics of neurones in this first relay station of the olfactory pathway were measured when the antennae were stimulated with five general green leaf volatiles, i.e. cis-3-hexen-1-ol, trans-2-hexenal, cis-3-hexenyl acetate, trans-2-hexen-1-ol and 1-hexanol. These compounds are part of the so-called green odour of potato, whose defined composition is essential for the beetle's host plant finding. The response spectra of deutocerebral neurones can be divided roughly into two classes: one class containing neurones which are not very specific for the tested compounds, and another class with highly specialized neurones. Their different responses to a potato leaf extract suggest two channels for the processing of olfactory information in the antennal lobe: one channel for the detection of the presence of green leaf odour components, and another one for an evaluation of the component ratios.

Responses of antennal olfactory receptors of the Colorado potato beetle (Leptinotarsa decemlineata Say) to stimulation with 5 general green odour components, i.e. cis-3-hexen-1-ol, trans-2-hexenal, cis-3-hexenyl acetate, trans-2-hexen-1-ol and 1-hexanol, were recorded extracellularly. Response spectra derived from these recordings cannot be classified into distinct reaction types. The spectra overlap in their sensitivity to individual stimuli, but there are differences in their degree of specialization with a gradual conversion from generalist to specialist receptors. Moreover, specialization is found to different stimuli. Receptor reactions to stimulation with binary mixtures of 3 of these compounds indicated that suppression of the response to one chemical by another is very common in olfactory receptor cells. The more a receptor is specialized, the stronger is this suppression. Suppression in narrowly tuned olfactory receptor neurones, therefore, is expected to play a fundamental role in the recognition of natural odour blends.