Adult Resident Population Research Articles

Cohort Profile: Estonian Biobank of the Estonian Genome Center, University of Tartu

The Estonian Biobank cohort is a volunteer-based sample of the Estonian resident adult population (aged ≥18 years). The current number of participants-close to 52000--represents a large proportion, 5%, of the Estonian adult population, making it ideally suited to population-based studies. General practitioners (GPs) and medical personnel in the special recruitment offices have recruited participants throughout the country. At baseline, the GPs performed a standardized health examination of the participants, who also donated blood samples for DNA, white blood cells and plasma tests and filled out a 16-module questionnaire on health-related topics such as lifestyle, diet and clinical diagnoses described in WHO ICD-10. A significant part of the cohort has whole genome sequencing (100), genome-wide single nucleotide polymorphism (SNP) array data (20 000) and/or NMR metabolome data (11 000) available (http://www.geenivaramu.ee/for-scientists/data-release/). The data are continuously updated through periodical linking to national electronic databases and registries. A part of the cohort has been re-contacted for follow-up purposes and resampling, and targeted invitations are possible for specific purposes, for example people with a specific diagnosis. The Estonian Genome Center of the University of Tartu is actively collaborating with many universities, research institutes and consortia and encourages fellow scientists worldwide to co-initiate new academic or industrial joint projects with us.

Population-based incidences of non-fatal injuries - results of the German-wide telephone survey 2004

BackgroundTo plan preventive measures against accident-related injuries, it is important to have detailed epidemiological data on this topic. The aim of this report was to present population-based incidence estimates of injuries due to non-fatal accidents in relation to age, gender and educational level.MethodsWe performed a cross-sectional telephone survey from 2003 to 2004 of the resident adult population of Germany, which included 7,341 subjects (response rate: 32.6 to 39.4%). The interview included 13 questions about injuries caused by accidents that happened in the 12 months preceding the interview. We estimated one-year cumulative incidences of injuries by gender, age and educational level.ResultsOverall, 10.3% of the subjects reported an unintentional injury requiring medical treatment in the previous 12 months. The age-standardised incidence of injuries was higher among men than women (men: 11.3%, women: 8.9%). Generally, accidents at home were the most frequently reported (27.4%). Men and women aged 18 to 29 years suffered accident-related injuries (and also repeated injuries) the most often during the preceding 12 months.Although the overall incidence of injuries caused by accidents did not differ by educational level, the incidences of accidents at different places differed by educational level. The incidence of work-related injuries was higher among people with a low educational level.ConclusionsOur age- and gender-specific results provide detailed insight into specific patterns of accident-related injuries in Germany. Young men are especially at high risk of injuries. This information is valuable because a nationwide comprehensive recording of injuries caused by accidents does not exist. The data highlight the target groups for injury prevention measures.

Subjektiver Sozialstatus und gesundheitsbezogene Lebensqualität bei Erwachsenen in Deutschland

The impact of subjective perception of social status on health has been analysed in international health research for several years. However, in Germany the empirical analysis of the relation between subjective social status (SSS) and health is still in the very early stages. This study investigates if health-related quality of life (HRQoL) in German adults is associated with SSS over and above conventional measures of social status. The results are based on the German General Social Survey (ALLBUS 2010), a representative cross-sectional survey of the adult resident population in Germany (n=2 827). HRQoL was assessed with 4 items referring to self-rated health (SRH) and impairment of well-being due to bodily pain, depressiveness, and loneliness. SSS was measured with a 10-point scale where participants rated their status in society. The impact of SSS on HRQoL was analysed separately for men and women using logistic regression models adjusted for age, school education, net equivalent household income, and occupational position. Poorer SRH, bodily pain, depressiveness, and loneliness occurred significantly more often in men and women with low SSS compared to those with higher SSS. After adjusting for age, education, income, and occupation, the effects of SSS on SRH and depressiveness remained significant in men and women (SRH: men: OR=4.76; 95% CI=2.52-8.99; women: OR=2.95; 95% CI=1.74-4.99; depressiveness: men: OR=2.86; 95% CI=1.60-5.10; women: OR=2.75; 95% CI=1.65-4.56). The effects of SSS on bodily pain and loneliness were observed only in women after adjustment for objective status indicators (OR=1.75; 95% CI=1.07-2.86 and OR=3.03; 95% CI=1.43-6.42, respectively). These findings indicate that self-perception of social disadvantage affects HRQoL in German adults independently and partly gender-specifically. Hence, complementary to objective status indicators the SSS offers additional potential for describing and explaining health inequalities.

Psychiatric morbidity in pain conditions: results from the Singapore Mental Health Study.

Chronic pain is a common problem among the general population and has been found to be associated with psychiatric disorders in studies based on both clinical samples and epidemiological surveys. To establish the prevalence, correlates and comorbidities of chronic pain disorders among the adult population of Singapore. The data used in the present analysis were derived from the Singapore Mental Health Study, a cross-sectional epidemiological survey of a representative sample of the adult resident population of Singapore. Diagnoses of psychiatric disorders were established using the Composite International Diagnostic Interview version 3.0. A modified version of the Composite International Diagnostic Interview 3.0 checklist of chronic medical disorders was used, in which the chronic medical disorders were reclassified into eight types of physical disorders. Chronic pain disorders included arthritis or rheumatism, back problems including disk or spine problems, and migraine headaches. The lifetime prevalence estimates for arthritis, back pain and migraine in the Singapore general population were 6.0% (n=282), 7.0% (n=436) and 5.6% (n=446), respectively. After adjusting for sociodemographic factors, comorbid pain disorders and the presence of other chronic physical conditions, migraine remained significantly associated with major depressive disorder (adjusted OR=2.4), generalized anxiety disorder (adjusted OR=3.0) and alcohol use disorders (adjusted OR=2.1), while back pain was significantly associated with major depressive disorder (adjusted OR=2.0). The significant association between pain and psychiatric disorders emphasizes the need to screen individuals with chronic pain conditions for psychiatric disorders, particularly depression. There is a need to develop integrated pharmacological and psychological treatments for both conditions.

Body mass index and risk of mental disorders in the general population: Results from the Singapore Mental Health Study

ObjectiveThe aims of the current study were to elucidate the association between Body Mass Index (BMI) and mental disorders and to examine whether these associations are moderated by socio-demographic correlates and comorbid physical disorders. MethodsThe Singapore Mental Health Study (SMHS) surveyed adult Singapore Residents (Singapore Citizens and Permanent Residents) aged 18years and above. The survey was conducted from December 2009 to December 2010. The diagnoses of mental disorders were established using the World Mental Health Composite International Diagnostic Interview version 3.0 (CIDI 3.0). BMI was calculated using height and weight which were self-reported by respondents. The Euro-Qol-5Dimensions (EQ-5D) was used to measure the health related quality of life (HRQoL) in the sample. ResultsSix thousand and six hundred sixteen respondents completed the study (response rate of 75.9%) and constituted a representative sample of the adult resident population in Singapore. Being underweight was associated with both lifetime (adjusted odds ratio (OR): 2.3) and 12-month obsessive–compulsive disorder (adjusted OR: 4.4). Obesity was associated with 12-month alcohol dependence (adjusted OR: 8.4). There were no significant differences in the EQ-5D indices or the EQ-VAS scores among the four BMI groups in the population. ConclusionsOur findings are somewhat unique and different from those reported in research from Western countries. There is a need for further cross-cultural research to explore and identify genetic, metabolic and cultural differences that underlie the interaction between obesity and mental illnesses.

Mental disorders: employment and work productivity in Singapore

To examine the association between mental disorders and work disability in the adult resident population in Singapore. Data are from the Singapore Mental Health Study, which was a household survey of a nationally representative sample. The main instrument used was the Composite International Diagnostic Interview (CIDI). Employment-related information was collected using the modified employment module of the CIDI. A total of 6,429 respondents were included in the analysis, 71 % (n = 4,594) were employed, 24.5 % (n = 1,522) were economically inactive and 4.5 % (n = 313) were unemployed. Among the employed, 2.3 % had a 12-month prevalence of at least one mental disorder, while 5.3 % of the unemployed had at least one mental disorder. The average number of work loss days (absenteeism) per capita among those with a mental disorder was 0.5 per month that is equivalent to an annualized national projection of approximately 0.3 million productivity days. The average work-cutback days (presenteeism) were 0.4 days among this group. Of the mentally ill in the workforce, a high proportion (86.5 %) did not ever seek help for problems related to mental health. Our findings provide information on the significant consequences of mental disorders on the workforce in terms of lost work productivity, which could pave the way for a more rational allocation of scarce resources.

Fruit and vegetable consumption among migrants in Switzerland.

To assess the relative risk of low daily fruit and vegetable consumption for six large migrant groups in Switzerland. Cross-sectional health survey carried out 2007 (Swiss Health Survey) and 2010 (Swiss Migrant Health Survey) in Switzerland. Multinomial logistic regression models were used to estimate relative risk rates (RRR) of migrants relative to Swiss nationals. Data obtained from representative samples of Swiss and foreign nationals living in Switzerland. A random sample (n =14637) of the Portuguese, German, Italian, Turkish, Serbian, Kosovan and Swiss permanent resident adult population (17-64 years old) was interviewed. The proportion of participants who adhered to the recommended fruit and vegetable consumption was below one-third in all study populations. Compared with Swiss nationals, the relative risk of low daily fruit and vegetable intake relative to recommended intake was higher in Turkish nationals (RRR = 2.92, 95 % CI 1.91, 4.48; P = 0.0000) and Kosovan nationals (RRR = 4.76, 95 % CI 3.01, 7.55; P = 0.0000). The respective relative risks of Portuguese, Serbian, German and Italian nationals were not significantly different from the Swiss reference group. Initiatives for the promotion of fruit and vegetable consumption should continue to address the population at large. At the same time, programmes that are tailored to the specific needs of migrants from Turkey and Kosovo should be considered.

Where do People with Mental Disorders in Singapore go to for Help?

This study aims to examine the pattern of services utilisation and the factors associated with help-seeking behaviour among those with mental disorders in the multi-ethnic Asian population of Singapore. A household survey was carried out on a nationally representative sample of the adult (18 years and above) resident population. The main instrument used to establish the diagnosis of mental disorders and the services sought was the Composite International Diagnostic Interview version 3.0 (CIDI 3.0). The 'services' component of the instrument contains questions, which examine service utilisation for mental health problems. A total number of 6616 completed respondents constituted a representative sample of the adult resident population in Singapore. Only 31.7% of those with mental disorders had sought help: 15.7% from mental health providers, 8.4% from general practitioners, and 7.6% from religious/ spiritual advisors or other healers. Among respondents with severe disability across any disorder assessed in our survey, 50.1% had sought help from some service in the past 12 months. Individuals with moderate or mild levels had lower rates of consultation, i.e. 35.4% and 30.6% respectively. The rate of using the Internet as a source of help was low in this population. There is a need to engage and work collaboratively with healthcare providers (including religious and spiritual healers) in the community to detect, assess and treat those with mental illness. More general practitioners need to be involved, and the role of the Internet also requires further consideration as a source for help.

Labour, the Enterprise Gap and the Red Queen

This paper shows that Labour's enterprise policy targeted a closure of the ‘enterprise gap’, which is a disparity in the number of enterprises per 10,000 of the resident adult population in less prosperous compared with wealthier regions. Labour's policy has assumed that this gap can be closed through an increase in startup rates in these less prosperous regions. The paper shows that while Labour has managed to deliver an improvement in start-up rates, this has not brought about a closure of the enterprise gap as they expected. It uses the Red Queen Effect as a metaphor to explore the reasons for Labour's failure to close the enterprise gap, concluding that the scale of the increase in start-up rates that would be necessary to begin closing the enterprise gap may be unrealistic.

Understanding the dynamics of neonicotinoid activity in the management of Bemisia tabaci whiteflies on poinsettias

The relative efficacies of registered label rates for foliar and soil drench treatments of imidacloprid and dinotefuran at preventing the establishment of Bemisia tabaci B biotype whitefly populations on newly infested poinsettia plants were evaluated. Pesticide levels within and on plant leaves were monitored for 10 weeks by ELISA and LC/MS in an effort to better understand the dynamics of neonicotinoid activity against this insect and to estimate insecticide concentrations needed to kill the nymphal and adult stages. While all treatments proved equally effective as a remedial measure for the control of the resident adult populations, thereby accomplishing the objective of foliar contact treatments, the dinotefuran soil drench application was the only treatment that provided multi-generational control of Bemisia populations.

Seroepidemiology of Dengue Virus Infection Among Adults in Singapore

To determine the seroepidemiology of dengue virus infection in a representative sample of the adult resident population aged 18 years old to 74 years old in Singapore and to estimate the proportion of asymptomatic dengue infection during the 2004 epidemic. The study was based on 4152 stored blood samples collected between September and December 2004 from participants aged 18 years old to 74 years old during the 2004 National Health Survey. Sera were tested for IgG and IgM antibodies using a commercial test kit (PanBio Capture/Indirect ELISA). Of the study population, 59.0% and 2.6% tested positive for dengue IgG (past infection) and IgM/high-titre IgG (recent infection), respectively. Only 17.2% of young adults aged 18 years old to 24 years old were dengue IgG positive. Multivariate analyses showed that older age, Indian ethnicity and male gender were significantly associated with past infection, whereas only age was significantly associated with recent dengue infection. Based on the dengue cases notified during the period of survey, it was estimated that for every 23 individuals recently infected with dengue, only 1 was reported to the health authority as a clinical case. The Singapore population is highly susceptible to dengue epidemics despite its aggressive Aedes prevention and control programme. The finding of a high proportion of unreported cases due to asymptomatic and subclinical infection poses a challenge for dengue control.

Air pollution effects on the respiratory health of the resident adult population in Turin, Italy

A case-control study was employed to investigate the relationship between atmospheric pollution and emergency hospital attendance for respiratory causes among adult and elderly patients resident in Turin in the period 1997 – 1999. Based on the primary diagnosis, adult (15 – 64 years) and elderly (>64 years) patients resident in Turin and admitted for respiratory causes were defined as Cases (n1 = 4.645); adult and elderly patients admitted for causes other than respiratory diseases or heart diseases were defined as Controls (n2 = 152.954). Sulfur dioxide (SO2 in µg/m3), total suspended particulate (TSP in µg/m3) and carbon monoxide (CO in mg/m3) were taken as indicators of urban air pollution; principal confounding factors were patient sex, age and education level; season, temperature, humidity, solar radiation; day of hospital admission. Statistical analysis was performed using logistic regression models. In accordance with Odds Ratio (OR) values and relative 95% Confidence Intervals (OR_95% CI) estimated by the models, associations are expressed as percent increase in risk (Increase%)1 and relative 95% Confidence Interval (95% CI) per 10 µg/m3 in SO2 and TSP, and per 1 mg/m3 in CO exposure. After adjusting for confounding factors, there was a mean increase in emergency hospital attendance of 2.20% (95% CI 1.70 – 2.60) and 2.55% (95% CI 1.79 – 3.32) per 10 µg/m3 increase in exposure to SO2 and TSP, respectively, and a mean increase of 5.30% (95% CI 3.00 – 7.70) per 1 mg/m3 increase in exposure to CO. A significant association was separately confirmed for SO2 and TSP in adult (15 – 64 years) and elderly (>64 years) patients, but for CO only among elderly patients. A significant association was found between the increase in emergency hospital attendance for respiratory causes and exposure to sulfur dioxide, total suspended particulate and carbon monoxide in Turin during the study period. This easy to use and manage case-control study produced results in line with those reported for other Italian and European cities.

Rise of the Carceral State

Jonathan Simon Rise of the Carcerai State N O PIECE OF T H E PR E SEN T C O N JU N C T U R E IS AS S T R IK IN G AS THE RAPID grow th of the American prison population. At its recent low point in the early 1970s, nearly 90 Americans were in prison for every 100,000 free residents. This was on the low side (but not dramatically so) of a tw entieth-century average o f about 100 per 100,000 residents. These num bers placed the United States well above all its liberal democratic peers, although well behind authoritarian governments like the Soviet Union or South Africa at the time. Beginning in the mid-1970s, the US incarceration rate began an unbroken climb of m ore than 25 years. By the end of 2000, nearly 500 residents of the United States were in prison for every 100,000 free persons (Beck and Harrison, 2001: l).1At this level, the American prison population far outstrips its liberal demo­ cratic peers and has reached levels comparable to those in authoritar­ ian or extremely poor countries. An even larger pool of people stands at considerable risk of being sent to prison because they are already on some form of lesser correctional custody, such as parole or probation. In m any cases these correctional subjects are only a technical violation away from being actual prisoners. For example, in Miami a young m ale on probation after pleading guilty to a “strong arm robbery” (that is, a purse snatch­ ing) was im prisoned for 10 years after missing an appointm ent w ith his probation officer. Including these subjects, the correctional population now includes nearly 3 percent of the adult resident population of the United States (Beck, Karberg, and Harrison, 2002).2 social research Voi 74 : No 2 : Summer 2007 471 W hen we look at the distribution of the correctional popula­ tion it is clear that the prison has become a norm al socializing institu­ tion for whole segments of American society.3 The m ost incarcerated portion of the population consists of young African-American males (with young Hispanic males close behind). Between the ages of 25 and 29 nearly 10,000 Black m ales are in prison for every 100,000 in the community, fully 10 percent of that entire population (Beck, Karberg, and Harrison, 2002: ll).4 At this level of “participation,” prison is for young African-American m en a more im portant institution for integrat­ ing them as subjects into adult roles than higher education, the mili­ tary, or marriage and is comparable to the labor m arket (and is far more im portant than any one industry or segm ent of that market). This “racialization” of punishm ent in America is terribly disturb­ ing for all the usual and compelling reasons. First, African Americans were the prim ary subjects of American slavery and the establishm ent of conditions of full freedom for African Americans has been a central objective of our constitutional system for almost a century and a half. Lore W acquant has described the present prison system as the m ost recent version of organized racial dom ination in America follow­ ing upon both slavery and the system of legal separation of the races enforced for m ost of the tw entieth century (Wacquant, 2000). Second, even putting aside the evidence of racial discrim ination in the crim inal justice system, the massive concentration of m inorities in the prison population has become an independent force separat­ ing the races. The spectacle of a generation of young m inority males im prisoned has reinforced w hite preferences for residential and school segregation. At th e same tim e, it challenges the ability of m inor­ ity com m unities to m aintain viable social networks (Clear and Rose, 1999), and exacerbates the presum ption of unfairness at the hands of the state.5 But beyond even its effects on the construction of racial identity— and where I would like to focus in this paper—the massive prison popu­ lation is posing an emerging challenge to the...

Incidence and short-term prognosis of status epilepticus in adults in Bologna, Italy.

To determine the incidence and the 30-day case fatality of status epilepticus (SE) in the adult resident population of the city of Bologna, Italy. Over a 1-year period (March 1, 1999 to February 29, 2000), all patients older than 20 years with SE were included. The case-finding method was based on (a) a prospective surveillance of all public general hospitals in the city by neurologic units, and (b) a review of all discharge codes concerning epilepsy. The crude and standardized annual incidence rate of SE was 13.1 per 100,000 [95% confidence interval (CI), 9.5-17.5] and 10.7 (95% CI, 7.5-13.8). It was higher in the elderly (older than 60 years) than in young adults (26.2 vs. 5.2) and in women than in men (14.9 vs. 11.0). Acute symptomatic SE accounted for 48%, and a cerebrovascular pathology was the most frequently associated etiologic condition (41%). A history of seizures was reported in 39% of patients. The 30-day case fatality was 39% (33% excluding postanoxic patients). This study reports the first data on the epidemiology of SE in Italy. The incidence rate found in the population of Bologna is in the same range as that of the other European countries. The 30-day case fatality is higher than all the other population studies (both European and American), despite the broadly similar clinical features of patients. Indirect evidence suggests that some inaccurate patient management could have negatively influenced the outcome of SE.

Machine gaming in Sydney clubs: characteristics of the supporting resident populations.

This research provided background for surveys and interviews in later stages of a 3 part project. It aimed to identify, from secondary research, sociodemographic characteristics which tend to support registered clubs and their machine gaming activities in the Sydney Statistical Division. Using multiple methods including Pearson's Product Moment correlation, Principal Components factor analysis, and stepwise regression, the study profiled Sydney populations which spend highly on gaming machines. The most important sociodemographic predictors of Sydney statistical local areas where per capita gaming machine expenditure is high are large proportions of the adult resident population who were born in Malta, Greece, Lebanon, China, Italy, Vietnam, Yugoslavia, India or the Philippines; have no vocational or tertiary qualifications; or are unemployed.

Survival, longevity and fecundity of overwintering Mesoplatys ochroptera Stål (Coleoptera: Chrysomelidae) defoliating Sesbania sesban (Leguminosae) and implications for its management in southern Africa

1 The defoliator beetle, Mesoplatys ochroptera Stal, is a serious pest of the legume tree sesbania (Sesbania sesban (L.) Merrill) in agroforestry systems in southern Africa. The survival of the overwintering stage of M. ochroptera and post- emergence longevity and fecundity of adults in sesbania fallows in eastern Zambia were quantified. 2 Only adult M. ochroptera survived during the winter (May–August) and the dry season (September–October) hidden under weeds, plant litter, in soil cracks and under rocks. During these periods, some beetles were occasionally found feeding on S. sesban, particularly in natural stands in humid areas. The adults were parasitized by the braconid Perilitus larvicida van Achterberg at a rate of 8.5–16.4%. The beetles stayed in the winter refuges for up to 210 days and emerged with the first heavy rains in October–November. The effective survival of beetles overwintering in an insectary was 18.1% in 1998 and 37.7% in 1999, and that of beetles overwintering in the field was estimated at 0.4 and 2.8% in 1998 and 1999, respectively. 3 The post-emergence longevity and oviposition period of females in the insectary was 14–31 days and 5–29 days, respectively. The post-emergence fecundity varied from 87 to 783. 4 It is concluded that the serious M. ochroptera infestation observed every year following the rains is due to synchronous emergence of overwintered resident adult populations and their high capacity for reproduction on many species of Sesbania. Recommendations for pest management in sesbania planted-fallows are given.

Home-range fidelity in the Australian sleepy lizard, Tiliqua rugosa

A study was conducted at a semi-arid site near Mt Mary, South Australia. Fifty-eight adult sleepy lizards, Tiliqua rugosa, were radio-tagged and regularly located over the spring season, when they are most active, for 2-5 years. Home-range area did not differ between males and females. Changes in home-range position between years were assessed by the distance between home-range centres measured at intervals of one, two, three or four years. Mean distances for successive years were less than the span of the home range in one year. The distance did not differ between sexes, it was not related to lizard size, nor did it increase with increased time interval. This implies that for the resident adult population, lizards retain their home ranges for at least five years, and that the sexes do not differ in their fidelity to home range.

TEMPORAL STABILITY OF LACTATE DEHYDROGENASE-A CLINES OF THE HIGH COCKSCOMB, ANOPLARCHUS PURPURESCENS.

In marine species with planktonic larval stages, strong geographic differentiation among resident adult populations is noteworthy in that identification of the forces and mechanisms which create such local differentiation allows an assessment of the relative importance of natural selection in promoting genetic divergence. Williams et al. (1973), and later Koehn and Williams (1978), focused on this problem in their analysis of genetic differentiation in the American eel, Anguilla rostrata. Their study centered on the interaction between age-dependent differentiation (elvers vs. resident adults) and spatial differentiation of groups along a latitudinal transect. They found different patterns of differentiation which depended upon the specific genetic marker under analysis. At the Mdh locus, allele frequencies were homogeneous among age-groups and among localities, suggesting recruitment of elvers from a common zygotic pool with no subsequent divergence between groups of colonists in situ. In contrast, at the Sdh locus, they observed a significant spatial component of variation across latitude, but one which was equally pronounced in both age groups. This result suggested (in light of the life history of the American eel) that divergence occurred prior to larval recruitment and was not further accentuated in situ. Finally, at the Phi-II locus, they observed that allele frequencies of newly recruited larvae were uniform across the transect (once again suggesting a common zygotic pool), but that geographic differentiation of adults was significant. This latter pattern would be consistent with a predominant role of local selective factors in promoting genetic divergence and it suggested selection intensities of about 10% per generation. Although the power of their analysis lies largely in the peculiar migrational history of the American eel, there is no reason to believe that the differences in genetic composition between life stages observed by Williams et al. (1973) and Koehn and Williams (1978) are in any way unique to Anguilla. As they point out, it is reasonable to expect that age-specific selection would operate in other species with planktonic larvae, but similar analyses have been rarely conducted. Actually, the degree of geographic differentiation in the American eel is rather slight; for example, systematic variation in Phi-II allele frequencies is on the order of 5% per degree of latitude (Koehn and Williams, 1978). In other marine fishes with planktonic larvae, more pronounced examples of geographic variation are known. In Anoplarchus purpurescens, an intertidal blennioid fish of the northwestern Pacific Ocean, relatively sharp differences in allele frequency over short distances have been reported (Johnson, 1971, 1977; Sassaman and Yoshiyama, 1979; Yoshiyama and Sassaman, unpubl.). Here we explore temporal (age-group) aspects of allele-frequency variation along two pronounced gradients of gene-frequency change in Anoplarchus. Our analysis follows the same logical format of Williams et al. (1973) and Koehn and Williams (1978). In addition we examine yearto-year stability of these gene-frequency clines by reference to previously published information (Johnson, 1971; Sassaman and Yoshiyama, 1979) for the same sampling sites. Since the presumption of extensive

Aspects of the Ecology of the Koala, Phascolarctos cinereus (Goldfuss), in Tucki Tucki Nature Reserve, New South Wales

A study of the koala colony in the 4-ha Tucki Tucki Nature Reserve in northern New South Wales was carried out between March 1972 and February 1976. The Reserve supported a resident adult population of 11 or 12 koalas, comprising three males and eight or nine females, and a mean total population of 26.5. Resident koalas engage in a high degree of local movement. Females are mature at the beginning of their third year and normally raise one young per year to independence. Males may not be fully mature till the commencement of their fourth year. Young are independent of the parent female at 12 months and disperse during their second year if unable to secure a vacant place in the Reserve. Dispersed koalas either take up residence in an adjoining colony, become nomads, or perish. During the study, all three resident males died over a short period. The gradual return to a stable population is examined.

Notes on Natural History and Behavior of Sceloporus undulatus erythrocheilus in Colorado

A population of the rock-inhabiting lizard, Sceloporus undulatus erythrocheilus was studied from May 1969 to March 1972 on a 3000 m2 study area in the Boulder Mountain Park near Boulder, Boulder Co., Colo. No predation was observed and the only ectoparasite found on the lizard was Geckobiella texana. The population decreased during the study, although the number of resident adults (10-15 per acre) remained about the same. The annual turnover of the resident adult population was about 35% and the maximum age estimation for an individual was 48 months. Lizards in the population were never active from. mid- November through early March. Reproductive activity began after emergence from brumation in late April and continued through mid-June. The testes reached maximum size during the breeding season and regressed to a low point in late July. Recrudescence began by September. Observed females laid one clutch of eggs per year with deposition occurring in late June or early July. Most of the activity of the sedentary females was the result of court- ship, feeding and thermoregulation. The males had a social hierarchy