Optical communications downlink from a low-earth orbiting 1.5U CubeSat.

In this article, we present the first demonstration of an optical communications downlink from a low-earth orbiting free-flying CubeSat. Two 1.5U vehicles, AC7-B&C, built under NASA's Optical Communications and Sensors Demonstration (OCSD) program were launched in November 2017 and subsequently placed into a 450-km, 51.6° inc. circular orbit. Pseudorandom data streams using on-off key (OOK) modulation were transmitted from AC-7B to a 40 cm aperture telescope located at sea level in El Segundo, CA. At 200 Mbps, without forward error correction (FEC), we achieved a 115-second link that was ~78% error free, with the remaining portion exhibiting an error rate below 1E-5. At the time of the engagement, the 1064-nm laser transmitter was operating at 2 W (half capacity) with a full width half maximum (FWHM) beam divergence of ~1 mrad, which was approximately double the anticipated pointing accuracy of the vehicle.

Bangladeshi school-age children's experiences and perceptions on child maltreatment: A qualitative interview study.

BACKGROUND: Child maltreatment (CM) is a public health problem and is recognized as a huge barrier for child development. Most of the research and definitions on CM are from the perspective of high-income western countries. Because no major studies have been conducted on CM in Bangladesh, the aim of the current study was to explore the experiences of and perceptions on CM in school-age children in rural and urban Bangladesh in order to understand maltreatment in a local context and from a child perspective. METHODS: Semistructured individual interviews with 24 children (13 boys and 11 girls), between the ages of 9 and 13 years of which 11 were schoolgoing and 13 non-schoolgoing, were conducted during July 2013 and analysed according to qualitative content analysis. RESULTS: CM was a common and painful experience with serious physical and emotional consequences but highly accepted by the society. Vulnerable groups were especially young children, girls, and poor children. The children's voices were not heard due to their low status and low position in their families, schools, and working places. The main theme that emerged in the analysis was children's subordination, which permeated the five categories: (a) perception of children's situation in society, (b) understanding children's development and needs, (c) CM associated to school achievement, (d) negative impact of CM, and (e) emotional responses. CONCLUSIONS: Different kinds of abuse are obviously common in Bangladesh, and the schools do not follow the law from 2011 prohibiting corporal punishment at school. The society has to take further steps to live up to the UN Convention on the Rights of the Child, which was ratified already in 1990, to protect the Bangladeshi children from CM.

Exploring risk for abuse of children with chronic conditions or disabilities--parent's perceptions of stressors and the role of professionals.

BACKGROUND: Children with chronic conditions or disabilities are at an increased risk for abuse. High level of parental stress has been identified as possible trigger for abuse, were a combination of several factors are of importance, as lack of social support and limited resources in the neighbourhood. Suggestions for preventive measures have merely focused on parenting strategies and targeted intervention programmes. So far, little attention has been paid on how the risk for abuse might relate to parent's perceptions of stressors and the role of professionals. The purpose of the current study was therefore to explore risk factors for abuse with focus on both parent-child and parent-professional relationships. METHOD: Semi-structured in-depth interviews with 15 parents of children with chronic conditions or disability were collected and analysed according to qualitative content analysis. FINDINGS: Three major themes were found that could be seen as risk factors for child abuse: (1) Emotional demands in precarious situations between parent and child. (2) Gradual shift in responsibility from professionals to parents concerning access to and co-ordination of service and support. (3) Emotionally closed environment between professionals and parents and taboo on talking about abuse. The gradual shift in responsibility had emotional implications, which could reinforce parental stress and thereby also indirect increase the risk of child abuse. The gradual shift in responsibility also seemed to generate an emotionally closed environment and reinforce the taboo on talking about abuse, which in turn hindered preventive measures. CONCLUSIONS: In the light of parent's perceptions of stressors and the role of professionals the findings indicate that abuse against children with chronic conditions or disability is not only a family matter, but also depending on qualities in service, professional support and social norms. The result pinpoints three challenges for preventive measures, all with emotional implications, parental strategies, organizational efforts and cultural awareness.

Molecular identification of hybrids of the invasive gibel carp Carassius auratus gibelio and crucian carp Carassius carassius in Swedish waters.

Both mitochondrial DNA sequence and two nuclear microsatellite markers were used to confirm the identity of the first record of Carassius auratus gibelio in the western (Swedish) Baltic Sea region. A total of 49 fishes were analysed, where 22 were from three Swedish sites connected to the Baltic Sea. The D-loop mitochondrial DNA sequences showed that 16 of 22 Swedish fishes were related to C. a. gibelio. The phylogenetic analysis of these sequences showed that these fish are probably not native, but represent different lineages of C. a. gibelio from China, Japan and Russia. All except three of these 16 fishes had microsatellite alleles suggesting hybridization with Carassius carassius. These findings suggest that a cryptic invasion of C. a. gibelio might be in progress.

Sever's injury: treatment with insoles provides effective pain relief.

Sever's injury (apophysitis calcanei) is considered to be the dominant cause of heel pain among children between 8 and 15 years. The traditional advice is to reduce and modify the level of physical activity. Recommended treatment in general is the same as for adults with Achilles tendon pain. The purpose of the study was to find out if insoles, of two different types, were effective in relieving heel pain in a group of boys (n=38) attending a Sports Medicine Clinic for heel pain diagnosed as Sever's injury. The type of insole was randomized, and self-assessed pain during physical activity in the treatment phase with insoles was compared with pain in the corresponding pre- and post-treatment phases without insoles. There were no other treatments added and the recommendations were to stay on the same activity level. All patients maintained their high level of physical activity throughout the study period. Significant pain reduction during physical activity when using insoles was found. Application of two different types of insoles without any immobilization, other treatment, or modification of sport activities results in significant pain relief in boys with Sever's injury.

Suicide mortality trends in young people aged 15 to 19 years in Lithuania.

AIM: This paper considers the suicide mortality trends from 1990-2009 in young people aged 15 to 19 years in Lithuania. METHODS: Suicide and injury mortality data, plus mortality data from all causes, were used to compare the trend lines. RESULTS: Suicide mortality rate in young people aged 15-19 years and in all population showed a rising trend from 1990, and then a decreasing trend from 2002 year. This trend was significant exclusively in boys. When comparing suicide deaths as a percentage of injury deaths and of all deaths in the age group 15-19 years, rising trends for boys were evident, whilst in girls, there was no evidence of change. CONCLUSIONS: In Lithuania, from early 1990s, the frequency of suicide increased amongst adults and young people aged 15-19 years. After 2002, a decrease in deaths by suicide was observed both for the whole population and for young people aged 15-19 years. The rise and fall was obvious for boys. The reasons for different trends may have been influenced by the political and socioeconomic instability in the 1990-2002 period, and the socioeconomic stability, together with active preventive measures, from 2002. Although the consumption of modern Selective serotonin reuptake inhibitors (SSRIs) increased during the same time, suicide mortality was again high during the economic crisis in 2008-2009.

PVC--as flooring material--and its association with incident asthma in a Swedish child cohort study.

UNLABELLED: The Dampness in Buildings and Health study (DBH) started in the year 2000 in Värmland, Sweden, with a baseline questionnaire sent to all children (n = 14,077) aged 1-6. Five years later, a follow-up questionnaire was sent to the children who were 1-3 years at baseline. A total of 4779 children participated in both the baseline and the follow-up studies and constitute the study population in this cohort study. The aim of this study was to examine the association between exposure to PVC-flooring in the child's and parent's bedroom in homes of children aged 1-3 and the incidence of asthma, rhinitis, and eczema during the following 5-year period. Adjusted analyses showed that the incidence of asthma among children was associated with PVC-flooring in the child's bedroom (AOR 1.52; 95% CI 0.99-2.35) and in the parent's bedroom (1.46; 0.96-2.23). The found risks were on borderline of significance and should therefore be interpreted with caution. There was further a positive relationship between the number of rooms with PVC-flooring and the cumulative incidence of asthma. PVC-flooring was found to be a stronger risk factor for incident asthma in multifamily homes when compared with single-family houses and in smoking families compared with non-smoking families and in women. PRACTICAL IMPLICATIONS: These longitudinal data from the DBH study found an association between the presence of PVC-flooring in the home and incident asthma in children. However, earlier results from the DBH study have shown that PVC-flooring is one important source for phthalates in indoor dust, and exposure to such phthalates was found to be associated with asthma and allergy among children. This emphasizes the need for prospective studies that focus on the importance of prenatal and neonatal exposure to phthalates in the development of asthma and allergy in children.

Low home ventilation rate in combination with moldy odor from the building structure increase the risk for allergic symptoms in children.

UNLABELLED: There are consistent findings on associations between asthma and allergy symptoms and residential mold and moisture. However, definitions of 'dampness' in studies are diverse because of differences in climate and building construction. Few studies have estimated mold problems inside the building structure by odor assessments. In a nested case-control study of 400 Swedish children, observations and measurements were performed in their homes by inspectors, and the children were examined by physicians for diagnoses of asthma, eczema, and rhinitis. In conclusion, we found an association between moldy odor along the skirting board and allergic symptoms among children, mainly rhinitis. No associations with any of the allergic symptoms were found for discoloured stains, 'floor dampness' or a general mold odor in the room. A moldy odor along the skirting board can be a proxy for hidden moisture problem inside the outer wall construction or in the foundation construction. There are indications that such dampness problems increase the risk for sensitization but the interpretation of data in respect of sensitization is difficult as about 80% of the children with rhinitis were sensitized. Furthermore, low ventilation rate in combination with moldy odor along the skirting board further increased the risk for three out of four studied outcomes, indicating that the ventilation rate is an effect modifier for indoor pollutants. PRACTICAL IMPLICATIONS: This study showed that mold odor at the skirting board level is strongly associated with allergic symptoms among children. Such odor at that specific place can be seen as a proxy for some kind of hidden moisture or mold problem in the building structure, such as the foundation or wooden ground beam. In houses with odor along the skirting board, dismantling of the structure is required for an investigation of possible moisture damage, measurements, and choice of actions. In homes with low ventilation in combination with mold odor along the skirting board, there was even a higher risk of health effects. This emphasizes the need for the appropriate remediation as this is an ever increasing problem in poorly ventilated houses that are damp.

Rock climbing injury rates and associated risk factors in a general climbing population.

The objective was to examine injury rates and associated risk factors in a representative sample of climbers. A random sample (n=606) of the Swedish Climbing Association members was sent a postal survey, with an effective response rate of 63%. Self-reported data regarding climbing history, safety practices and retrospective accounts of injury events (recall period 1.5 years) were obtained. Descriptive statistical methods were used to calculate injury incidences, and a two-step method including zero-inflated Poisson's regression analysis of re-injuries was used to determine the combination of risk factors that best explained individual injury rates. Overall, 4.2 injuries per 1000 climbing hours were reported, overuse injuries accounting for 93% of all injuries. Inflammatory tissue damages to fingers and wrists were the most common injury types. The multivariate analysis showed that overweight and practicing bouldering generally implied an increased primary injury risk, while there was a higher re-injury risk among male climbers and a lower risk among the older climbers. The high percentage of overuse injuries implies that climbing hours and loads should be gradually and systematically increased, and climbers regularly controlled for signs and symptoms of overuse. Further study of the association between body mass index and climbing injury is warranted.

Health behaviours, risk-taking and conceptual changes among schoolchildren aged 7 to 19 years in semi-rural Sweden.

BACKGROUND: This study covers a broad age group (7-19 years) and includes a wide range of themes. The aim is to describe how various behaviours, complaints and conceptual changes come into play and to discuss the factors that might support or hamper the happiness and well-being of growing children and adolescents. We also discuss the implications of our findings for future prevention programmes. METHODS: This cross-sectional study included all schoolchildren in a semi-rural district in Sweden (2181 pupils). A structured classroom questionnaire was used but the children were also given the opportunity to describe in their own words what was important for their happiness and well-being. RESULTS: Mean response rate was 85%. Most changes in behaviour occurred between 11 and 14 years of age. Girls had a more rapid process of change than boys. Both girls and boys experienced stress in their relations with peers, parents and teachers. Gender differences in emotional support were prominent. Regardless of age and sex, all schoolchildren asked for a richer choice of leisure time activities, a place where they could meet with friends and caring teachers, parents and adults in the surrounding community. CONCLUSIONS: Adolescence was perceived as a risky and problematic period not only by adults but also by the adolescents themselves. However, the perceived risks and the worries differed. While the adults mainly worried about the early onset of smoking and drug use, the schoolchildren worried about their social situation and their personal relationships. After decades of preventive programmes in Swedish schools, only modest results are seen. To be effective, future preventive programmes probably have to focus more on the conceptual world of the growing child.

Ethnic differences: word descriptors used by African-American and white asthma patients during induced bronchoconstriction.

STUDY OBJECTIVES: To determine if African-American and white patients with asthma (1) differ in the words they use to describe their breathlessness, and (2) differ in their perception of breathlessness. DESIGN: Descriptive cross-sectional design. SETTING AND PARTICIPANTS: The study setting was located in Northern California, an ethnically and economically diverse area. A total of 32 subjects, 16 per group, completed the study. MEASUREMENTS: All had a provocation concentration of methacholine chloride causing a 30% fall in FEV(1) (PC(30)) of

The presence and expression of hetR in the non-heterocystous cyanobacterium Symploca PCC 8002.

The filamentous cyanobacteria Symploca PCC 8002 (Symploca) and Trichodesmium spp. fix nitrogen aerobically in the light in a light/dark cycle, without forming specialized thick-walled cells (heterocysts). Even though they do not form heterocysts, we amplified and sequenced a segment of a key regulatory gene in heterocyst differentiation, the hetR gene, from Symploca, Trichodesmium erythraeum and Leptolyngbya PCC 73110 (which fixes nitrogen anaerobically) using degenerate oligonucleotides. The transcriptional level of hetR in Symploca PCC 8002 was examined in relation to nifH expression during nitrogen step-down. The expression pattern of hetR suggests that it was not induced during removal of combined nitrogen, as is the case with the heterocystous cyanobacteria. This is the first report of sequences corresponding to a portion of hetR from within the group of non-heterocystous cyanobacteria.

Use of biological markers of airway inflammation to detect the efficacy of nurse-delivered asthma education.

OBJECTIVE: The purpose of this study was to determine whether analysis of the constituents of induced sputum could be used to document the efficacy of a nurse-delivered patient education intervention and whether changes in the biological markers of inflammation in sputum would correlate with improvements in pulmonary function and symptoms. DESIGN: The study design was prospective, open trial with repeated measures. SETTING: The study took place at a West Coast academic medical center laboratory. SUBJECTS: Subjects included 12 nonsmoking persons with asthma, ages 23 to 51 years, on prescribed daily anti-inflammatory inhaled therapy who had not required oral prednisone in the previous 4 weeks of enrollment. METHOD: The effect of one 30-minute asthma education session on spirometry, peak flow, symptoms, and biological markers of inflammation in sputum was tested for 8 weeks to determine whether biological markers reflect the efficacy of educational interventions. RESULTS: Mean symptom scores decreased and lung function increased slightly over 8 weeks. Markers of eosinophil degranulation decreased by 50% and albumin by 25% from baseline to 8 weeks. Eosinophil percentages dropped 20% over time but did not change consistently at all time points. Clinical markers of asthma control correlated in the low-to-moderate range with biological markers of airway inflammation. CONCLUSION: The results of this study show the effects of a patient education intervention can be detected in both clinical and biological outcomes. Individual education may influence self-care of asthma including adherence to inhaled corticosteroid therapy and thereby suppress airway inflammation.

Alcohol, head injury, and pulmonary complications.

The purpose of this study was to determine the difference in rates of pulmonary complications (e.g., aspiration, pneumonia) in head-injured patients with and without concomitant alcohol intoxication. The records of 98 consecutive patients admitted over a 1-year period to a Level I Trauma Center were reviewed. The patients were grouped into three subsets: acutely intoxicated (n = 26), acutely intoxicated with a diagnosis of chronic alcoholism (n = 14), and non-intoxicated (n = 58). Alcohol intoxication was defined as a blood alcohol level (BAL) > or = 0.08 mg/dl. Admission BALs and Glasgow Coma Scale (GCS) scores were tabulated at admission. Frequency of arterial blood gas (ABG) measurements, need for an artificial airway/mechanical ventilation, and length of stay (LOS) were analyzed by using one-way analysis of variance. Intergroup differences in breath sounds were compared by using the nonparametric Kruskall-Wallis technique. We found no statistical difference between groups in terms of pulmonary sequelae despite the remarkably high BALs observed in the study groups. Similarly, there was no statistically greater LOS in the groups with alcohol intoxication than in alcohol-free cohorts. Despite a great deal of BAL science research to support our hypothesis, we failed to demonstrate a significantly higher rate of pulmonary problems in inebriated individuals with head injuries. We found that our strict exclusion criteria (no concomitant chest, abdominal, or pelvic trauma) limited the sample to only those patients without significant intracranial bleeding, whereas most complications in blood alcohol neuroscience research have been associated with much larger mass lesions (e.g., epidural or subdural hematomas). In addition, we found the characterizations of patients as chronically alcoholic were cumbersome and inaccurate in many cases. Future research should allow for a greater range of concomitant injuries that might suggest a positive or negative relationship to acute intoxication.

Dental health in suburban Jordanian preschool children.

There is no previous report from Jordan on dental health in preschool children. In the present study, carried out from November 1988 to January 1989, 255 Jordanian children aged 6 months to 6 years and living in a suburb of Amman were examined for dental caries and related factors. The disease was clinically visible in the second year of life. In the age group 3-6 years 72% had acquired caries, most of them severe. Boys and girls were affected similarly. The prevalence of caries was independent of social background factors. The reason for the high prevalence was probably early and uncontrolled intake of sweets combined with absence of dental cleaning. The authors pose that dental caries is becoming a major health problem among suburban Jordanian children and propose that this preventable disease should be tackled a the child health centers through teaching programmes directed to parents, commencing when the child is under one year of age.

Governance and implementation of sports safety practices by municipal offices in Swedish communities.

The objective of this study was to explore whether all-purpose health or safety promotion programmes and sports safety policies affect sports safety practices in local communities. Case study research methods were used to compare sports safety activities among offices in 73 Swedish municipalities; 28 with ongoing health or safety promotion programmes and 45 controls. The offices in municipalities with the WHO Healthy Cities (HC) or Safe Communities programmes were more likely to perform frequent inspections of sports facilities, and offices in the WHO HC programme were more likely to involve sports clubs in inspections. More than every second, property management office and environmental protection office conducted sports safety inspections compared with less than one in four planning offices and social welfare offices. It is concluded that all-purpose health and safety promotion programmes can reach out to have an effect on sports safety practices in local communities. These safety practices also reflect administrative work routines and managerial traditions.