Quantitative description of short-range order and its influence on the electronic structure in Ag-Pd alloys

We investigate the effect of short-range order (SRO) on the electronic structure in alloys from the theoretical point of view using density of states (DOS) data. In particular, the interaction between the atoms at different lattice sites is affected by chemical disorder, which in turn is reflected in the fine structure of the DOS and, hence, in the outcome of spectroscopic measurements. We aim at quantifying the degree of potential SRO with a proper parameter. The theoretical modeling is done with the Korringa-Kohn-Rostoker Green's function method. Therein, the extended multi-sublattice non-local coherent potential approximation is used to include SRO. As a model system, we use the binary solid solution Ag c Pd1-c at three representative concentrations c  =  0.25, 0.5 and 0.75. The degree of SRO is varied from local ordering to local segregation through an intermediate completely uncorrelated state. We observe some pronounced features, which change over the whole energy range of the valence bands as a function of SRO in the alloy. These spectral variations should be traceable in modern photoemission experiments.

Lithography-free oxide patterns as templates for self-catalyzed growth of highly uniform GaAs nanowires on Si(111)

We report self-catalyzed growth of GaAs nanowires (NWs) on Si/SiOx patterns fabricated by a lithography-free method. The patterns are defined using droplet epitaxy of GaAs nanocrystals, spontaneous oxidation, and thermal annealing. We investigate the influence of the size and density of the nucleation sites on the NW growth process and show that this approach enables the fabrication of highly uniform GaAs NWs with controllable density. The pattern fabrication and NW growth process are studied and discussed in relation to the surface morphology and chemical properties of the Si/SiOx patterns. Furthermore, the optical quality of the NWs is investigated by photoluminescence experiments performed for GaAs–AlGaAs core–shell NWs.

Anomalous bismuth-stabilized (2x1) reconstructions on GaAs(100) and InP(100) surfaces

First-principles phase diagrams of bismuth-stabilized GaAs- and InP(100) surfaces demonstrate for the first time the presence of anomalous (2x1) reconstructions, which disobey the common electron counting principle. Combining these theoretical results with our scanning-tunneling-microscopy and photoemission measurements, we identify novel (2x1) surface structures, which are composed of symmetric Bi-Bi and asymmetric mixed Bi-As and Bi-P dimers, and find that they are stabilized by stress relief and pseudogap formation.

Physical activity compensates for increased mortality risk among older people with poor muscle strength

The aim of the study was to determine whether habitual physical activity can compensate for the increased mortality risk among older people with poor muscle strength. Mortality was followed up for 10 years after laboratory examination in 558 community dwelling 75- and 80-year-old men and women. Maximal isometric strength of five muscle groups was measured and tertile cut-off points were used to categorize participants. Participants, who reported moderate physical activity for at least 4 h a week, were categorized as physically active and the others as sedentary. High muscle strength and physical activity both protected from mortality, but their effect was not additive. Within each muscle strength tertile, physically active people had a lower mortality risk than sedentary people, the effect being most pronounced among those with lower strength in all muscle groups. A high level of physical activity may thus compensate for the increased mortality associated with low muscle strength.

A population-based study on the risk of cervical cancer and cervical intraepithelial neoplasia among grand multiparous women in Finland

Previous studies suggest that high parity increases the risk of cervical cancer. We studied the risk of cervical cancer (CC) and cervical intraepithelial neoplasia (CIN3) in a Finnish cohort of grand multiparous (GM) women (at least five children) with low prevalence of sexually transmitted infections (STI). The Finnish Cancer Registry data revealed 220 CC and 178 CIN3 cases among 86 978 GM women. Standardised incidence ratios (SIR) were calculated from the numbers of observed and expected cases. Interval analyses by parity, age at first birth and average birth interval were done using multivariate Poisson regression. Seroprevalence of human papillomavirus (HPV) 16 and Chlamydia trachomatis was tested among 561 GM women and 5703 women with 2–4 pregnancies. The incidence among GM women was slightly above the national average for squamous cell carcinoma of cervix uteri (SIR 1.21, 95% CI 1.05–1.40) and CIN3 (1.37, 95% CI 1.17–1.58), but lower for adenocarcinoma (SIR 0.77, 95% CI 0.52–1.10). The seroprevalence of HPV16 and Chlamydia trachomatis among GM women was lower than in the reference population, except among those women who had their child under age 19. Age under 20 years at first birth increased the risk of CC and CIN3 especially in premenopausal GM women, while increasing parity had no effect. The small relative risks of CC and CIN3 among GM women in our study as compared to studies from other countries can be explained by the exceptionally low prevalence of STIs in Finnish GM women. The observed SIRs between 1.2 and 1.4 should be interpreted to represent increased risk attributable to grand multiparity. The increased incidence of CC and CIN3 among young GM women suggests causal association to HPV 16 and Chlamydia trachomatis infections.

Coping with activities of daily living in different care settings

OBJECTIVE

To measure the functional capacity of elderly people cared for in different health and welfare care settings, with functional capacity defined in terms of activities of daily living.

SUBJECTS AND METHODS

We assessed all people aged > or =65 in health-centre hospitals or nursing homes or receiving home nursing and home help services in Central Finland (n=5652) using the Evergreen activities of daily living index, which comprises nine physical and nine instrumental activities of daily living.

RESULTS

Assessments of functional capacity were obtained for nearly all subjects: only 33 forms (0.6%) were returned with incomplete data. The mean activities of daily living sum score (range 0-54) was lowest for women receiving home nursing (17.3), and highest for women in long-term care at health-centre hospitals (48.4). Low scores described good and high scores poor functional capacity. Age showed no association with the mean activities of daily living sum score in any of the care settings.

CONCLUSION

The Evergreen activities of daily living index was easy to use and successfully distinguishes between people in different care settings. Policies of assigning older people to different settings appear to be sound and sensible as the main defining criterion is level of functional capacity rather than age.

Body composition, smoking and physical activity in 75-year-old men and women in three Nordic localities with special reference to diagnosed diseases

PURPOSE

To describe and compare anthropometric characteristics among populations of 75-year-olds in three Nordic localities and to investigate possible relationships with chronic heart disease (CHD), chronic lung disease (CLD), diabetes mellitus, arthrosis and life-style factors such as smoking and physical activity.

MATERIAL AND METHODS

Anthropometric data were measured in 104 men and 191 women in Jyvaskyla (Finland), 196 men and 209 women in Glostrup (Denmark) and in 127 men and 167 women in Goteborg (Sweden). Variables assessed were body height, body weight, BMI, waist/hip ratio, skinfolds from several sites and percent body fat by bioelectrical impedance. The diagnosis of diseases were made by a physician based on the individual's medical history, drugs and medical examination. Physical activity was recorded by self-rating.

RESULTS

Men in Goteborg were taller and had a higher body weight while there was no difference in BMI among the men. Among women, those in Goteborg were tallest, while those in Jyvaskyla had the highest body weight, BMI, percent of body fat and waist/hip ratio. Biceps and triceps skinfolds were highest in men from Goteborg, while in women triceps and subscapular skinfolds were highest in those from Jyvaskyla. CHD was most common in those from Jyvaskyla, and women with CHD had a higher body weight, BMI and lean body mass in all three localities. Lean body mass was lower in men and women with CLD and women with CLD were also shorter, with a lower body weight, BMI, and percent body fat. Diabetes mellitus was associated with a higher body weight, BMI, percent body fat and lean body mass in women, but not in men. Both men and women with arthrosis had a higher BMI, while smoking was only associated with CHD in those from Jyvhskyla. In men with CHD the proportion of persons with low physical activity was higher in all three localities. The physical activity was also lower among men with CLD and diabetes mellitus in Goteborg and Glostrup.

CONCLUSION

There were anthropometric differences among 75-year-olds in the three Nordic localities. CHD and CLD were associated with various anthropometric variables. These findings may reflect either cause and effect relationships between diseases and anthropometric characteristics or differences in life-style factors influencing morbidity.

Increased lifetime prevalence of dental trauma is associated with previous non-dental injuries, mental distress and high alcohol consumption

The purpose of the study was to assess the lifetime prevalence of dental injuries and risk factors involved in a general population-based birth cohort. The study population consisted of 5737 subjects who had participated in a health survey at the age of 31 years. Altogether 52% of the participants were women. This partly computer-based health survey included two questionnaires on previous dental and non-dental injuries, general health, occupational status and lifestyle. The current study was based on these questionnaires. The lifetime prevalence of dental fractures was 43% and the lifetime prevalence of dental luxations and exarticulations 14%. Men more commonly had dental injuries than women. Particularly mental distress and a history of previous injuries were shown to increase the risk for dental injuries. Furthermore, overweight and high alcohol consumption were positively associated with a high lifetime prevalence of tooth trauma. Regular physical activity decreased trauma occurrence. Socioeconomic status further affected the lifetime prevalence of dental injuries. The conclusion of the study was that personal, social and physical factors played a role in the occurrence of dental trauma.

Prediction of recovery from neurosensory deficit after bilateral sagittal split osteotomy

OBJECTIVE

To observe the suitability of different combinations of readily available tests to predict recovery from a neurosensory deficit after bilateral sagittal split osteotomy (BSSO).

STUDY DESIGN

Thirty patients scheduled for BSSO were examined before surgery and 4 days, 3 weeks, 3 months, 6 months, and 1 year after surgery. At each follow-up, the patients self-evaluated the subjective neurosensory deficit of the lower lip and chin of both sides. Neurosensory function was also measured by tests consisting of light touch, 2-point discrimination, pin tactile discrimination, thermal discrimination, and sensibility testing of the mandibular molars. The positive predictive values (PPV) of each test for recovery from the neurosensory deficit were calculated. Furthermore, different tests were combined, and the PPVs for recovery from the neurosensory deficit of these combinations were analyzed.

RESULTS

A positive response to sensibility testing of the mandibular first and second molars 4 days and 3 weeks after surgery was related to a PPV of 100% and 87%, respectively, for full recovery from sensation loss at 1 year. However, none of the tests alone could reliably predict recovery from the neurosensory deficit after BSSO. When 3 different tests were combined, the best results were achieved by the combinations of a light test or a 2-point discrimination test and a pin tactile test with the sensibility testing of mandibular molars.

CONCLUSIONS

Sensibility testing of mandibular molars can be used to predict recovery from the neurosensory deficit after BSSO. The best positive predictive ability can be achieved by combining a mechanoceptive test, a nociceptive test, and sensibility testing of mandibular molars.

Health and functional capacity as predictors of community dwelling among elderly people

The aim of this study was to identify factors that predict community dwelling (i.e., nonuse of institutional bed-days) among elderly people. This was a longitudinal study of institution use including both short-term and long-term use of hospitals and nursing homes. The impact of health, functional performance, and carrying out the activities of daily living on community dwelling was studied using the method of path analysis. The participants were all the 75-year-old (N = 388) and 80-year-old (N = 291) men and women resident in the City of Jyväskylä, Finland. Predictor variables included disease severity, symptoms of illness, cognitive capacity, walking speed, muscle strength, hearing, and ability to carry out the activities of daily living. The outcome variable was community dwelling. Over 70% of the elderly people had received institutional care during the 5-year follow-up. The path analysis models showed that disease severity and symptoms of illness had an effect on community dwelling: those with a more severe disease or more symptoms needed more institutional care. The effect was also mediated through limitations in physical performance and cognitive capacity and need for assistance in activities of daily living. The explanatory power of these models varied from 23% to 36%. The results of this study suggest that prevention, treatment, and rehabilitation programs aimed at the promotion of community dwelling in elderly people should focus on the severity of diseases, functional performance, and the ability to carry out the activities of daily living.

Self-efficacy as a common variable in oral health behavior and diabetes adherence

Successful treatment of dental caries, periodontal diseases and diabetes requires persistent daily self-care. The aim of this study was to evaluate the perception of self-efficacy as a common behavioral factor determining oral health behavior, diabetes self-care, and actual health status. Cross-sectional data relating to 149 insulin-dependent diabetes mellitus (IDDM) patients were collected from patient records, and by clinical oral examination and a quantitative questionnaire. The study population was recruited from different locations, and the participation percentage was 80%. Self-efficacy scales associated with corresponding behaviors, and a dental self-efficacy scale also correlated with dental caries. Dental self-efficacy correlated with diabetes self-efficacy, diabetes adherence, and with HbA1c. Also, logistic regression analysis revealed that dental self-efficacy was related to diabetes adherence. Further, those diabetics reporting a high frequency of dental visiting had higher diabetes self-efficacy. As a conclusion, good dental self-efficacy has a positive influence on diabetes adherence. The results suggest that the perception of self-efficacy may be a common behavioral factor determining diabetes self-care and oral health behavior.

A comparative study of factors related to carrying out physical activities of daily living (PADL) among 75-year-old-men and women in two Nordic localities

The aim of this cross-sectional and cross-national study was to describe and compare the ability to carry out physical activities of daily living (PADL) and examine factors that might explain variation in this ability in two Nordic populations. Seven hundred and six men and women aged 75 from two populations (Glostrup, Denmark, and Jyväskylä, Finland) were interviewed and given a laboratory examination in 1989-90. The ability to carry out the PADL activities was studied by interview. Tests were given to determine depressive symptoms, cognitive capacity, and selected physical and sensory performance domains. Four different regression models (men and women in Jyväskylä and Glostrup) were used to analyze a number of variables describing physical and psychological health and performance related to the PADL. Knee extension strength and stair mounting height in three models (men and women in Jyväskylä and women in Glostrup), and walking speed in one model (men in Glostrup) emerged as explanatory factors on the basis of the physical performance tests done. Sight, except in the women in Glostrup, hearing in the men in Jyväskylä, and balance in the women in Glostrup also explained PADL functioning. In addition, symptoms of depression in the men in Glostrup, and symptoms of illness, except in the men in Jyväskylä, and cognitive capacity in the men in Jyväskylä emerged as explanatory factors in the regression models. There were, however, no major differences in the determinants of PADL functioning in the two Nordic populations of elderly people. Physical, psychological and sensory tests provide useful information, complementary to self-reports regarding declining PADL functional capacity.

Calcaneal bone mineral density predicts fracture occurrence: a five-year follow-up study in elderly people

A 5-year follow-up study investigated calcaneal bone mineral density (BMD) and changes in BMD in relation to fracture occurrence. The subjects comprised two cohorts born in 1914 and 1910 living in the city of Jyväskylä in central Finland. One hundred and three men (82%) and 188 women (73%), aged 75, and 57 men (74%) and 136 women (65%), aged 80, of the eligible population participated in the baseline bone measurements. The follow-up bone measurements were obtained for 59 men (68%) and 119 women (66%), aged 80 years, and for 21 men (53%) and 61 women (48%), aged 85 years. During the follow-up period, 8 men and 36 women from the younger and 11 men and 24 women from the older cohort sustained at least one fracture. When the baseline levels of BMD were related to fracture occurrence, the results clearly showed that with increased BMD values the probability of fracture decreased. Where men and women had similar BMD values, they also had a similar fracture probability. Except for one woman in the older cohort, none of those who had initial BMD values more than 1 standard deviation above the mean for their age developed a fracture during the follow-up period. The mean annual decrease in BMD was greater in the women (2.5-2.7%) than in the men (0.8-1.0%). The BMD change tended to associate with fracture occurrence only in the 75-year-old women (p = 0.075). The results suggest that calcaneus BMD can be used as a predictor of fracture occurrence in 75- to 80-year-old men and women. However, associating fractures with the change in BMD was difficult due to the limited number of survivors and initial differences in BMD values.

Morbidity and disability in 75- and 80-year-old men and women. A five-year follow-up

Purpose of this report is to describe the changes that occurred in morbidity, symptoms of illness and disability of 75- and 80-year-old residents of Jyväskylä, Finland, over a five-year period. The study population consisted of the elderly residents of the city of Jyväskylä in central Finland who were born in 1914 and 1910. At baseline (in 1989 and 1990), 355 (92.9%) persons from the younger age group and 262 (91.9%) from the older age group were interviewed and 311 (81.4%) and 230 (80.7%), respectively, took part in the physical examination. At follow-up (in 1994 and 1995), the corresponding numbers were 250 (93.3%) and 148 (88.6%) for the interviews and 217 (81.0%) and 127 (76.0%) for the physical examinations. The prevalence of chronic conditions was determined in connection with the medical examinations on the basis of self-report and the respondent's prescriptions and medical information cards. To measure the occurrence of symptoms, the respondents were asked whether during the past 14 days they had suffered from any of 17 listed symptoms. Functional capacity was assessed in connection with the interview carried out at the respondent's home in terms of needing help in activities of daily living (ADL). In the baseline examinations, subjects were found to have on average 2-3 diseases. During the follow-up the number of diseases and the proportion of people with co-morbidity increased in both age groups. Both men and women had on average 1-2 symptoms that caused them much trouble, and the number of such symptoms increased to some extent during the follow-up. The proportions of those needing help increased during the follow-up in all groups and the increase was most prominent among the women of the older age group. Of those who managed independently with physical ADL (PADL) at baseline, 14.9%-44.9% reported need of help in at least one task at follow-up. The need for help in PADL was greatest with cutting toe-nails, negotiating stairs, moving outdoors, washing the upper body and in instrumental ADL (IADL) with vacuuming, shopping, handling finances and in the use of public transport. Successful prevention and postponement of functional disabilities in the elderly population depends not only on the early diagnosis of illness but also on identifying even minor signs and symptoms of disease and functional limitations, and to focus health care interventions accordingly.

Muscle strength and mobility as predictors of survival in 75-84-year-old people

The purpose of the study was to examine the association of physical capacity, as determined on the basis of self-report and physical measurements, with survival in three groups of elderly people aged 75, 80 and 75-84 years. The main aspects of physical capacity were mobility, walking speed, hand grip strength and knee extension strength. Although 1142 persons participated in mobility interview, of whom 466 also took part in the walking speed test, and 463 in the strength tests. The follow-up periods ranged from 48 to 58 months. Risk of death was significantly related to difficulties in indoor mobility among the 75-84-year-olds (odds ratio = 1.99, 95% confidence interval = 1.27-3.13) and 75- and 80- year-olds (OR = 1.60, CI = 1.07-2.38) and outdoor mobility among the 75-84-year-olds (OR = 2.44, CI = 1.63-3.67) and 75- and 80-year-olds (OR =2.75, CI = 1.72-4.40). The odds ratios for hand grip strength (OR = 1.86, CI=1.13-3.07), knee extension strength (OR =2.52, CI = 1.50-4.42) and walking time over 10 meters (OR = 1.98, CI = 1.18-3.34) for the 75- and 80-year-olds were also significant. Since these variables can be easily measured and provide valuable information about functional capacity and risk of death they merit inclusion in medical examination of elderly clients.

Factors related to carrying out everyday activities among elderly people aged 80

The study was based on an epidemiological model in which performing activities of daily living (ADL) was the dependent variable. Variation in performing was explained by physical and mental health, and by physical performance. The population consisted of all 80-year-old residents (N = 291) of the city of Jyväskylä in central Finland; 90% of them agreed to take part in the interviews at home, while 72% took part in the laboratory examinations to determine health status and functional capacity. Difficulties in at least some PADL (Physical Activities of Daily Living) tasks were reported by 86.5% of the men, and 87.2% of the women; none said they could perform all IADL (Instrumental Activities of Daily Living) tasks without difficulty. Physical performance (grip strength and stair mounting test in men, and stair mounting test, balance, and upper extremity function test in women) and visual acuity showed a significant association with ADL performance both in men and in women. In addition, depressive symptoms in women, and cognitive capacity in men were associated with both PADL and IADL, and ADL performance, respectively. In the search for pathways to reduced ADL performance, it is important to look not only at chronic diseases but also at the aging processes as well as the disabilities caused by inactivity. Tests of cognitive capacity, psychological well-being and physical performance provide valuable information on the factors that underlie the aged individual's reduced functional capacity.

Use of drugs by non-institutionalized urban Finns born in 1904-1923 and the association of drug use with mood and self-rated health

The purpose of this study was to examine the use of drugs by elderly people and to investigate its associations with various other factors. Random sampling was used to select 800 interviewees born in 1904-13 and a further 800 born in 1914-23. The average number of prescribed drugs per person was 2.2. Women used a greater number of prescribed drugs than did men; and this difference increased with age. The use of vitamins and trace elements seemed to decline with increasing age. Among women a significant association between the use of prescribed drugs and depressive symptoms was found. Women in the older age group used prescribed drugs more often than women in the younger age group. One fifth of the subjects had a greater number of drugs in simultaneous use than is generally recommended. It seems that, especially among elderly women, depression often remains undiagnosed and treatments are chiefly provided for the associated symptoms.