Supporting positive development in early adolescence: A school-based intervention in Turkey

ABSTRACT

We present a youth development intervention program and its evaluation. Deriving from the theories of agentic self and positive youth development, we adopted a holistic perspective that focused on social agency with growth mindset and self-efficacy conceptualized as its motivators. The intervention consisted of 14 weekly sessions with 508 sixth graders in four public schools in Turkey (M_age?=?11.8, 49% female). A comparable group with 417 sixth graders in five public schools served as the control group (M_age?=?11.7, 47% female). All students came from families of low to middle socioeconomic status. The evaluation had an experimental design with pretest, posttest (4 months after pretest), and follow-up (11 months after posttest) assessments. Findings indicated beneficial effects of the intervention on mindset, self-efficacy, and some indicators of social agency, some of which were sustained through the follow-up. In concordance with previous research on early adolescents, a general decline in positive adaptation was observed in the control group between pre- and posttests.     

Efficacy of a school-based childhood obesity intervention program in a rural southern community: TEAM Mississippi Project

A healthy lifestyle school-based obesity intervention was evaluated in a rural southern community where the rate of obesity ranks as the highest. School-age children (N = 450) ranging from 6 to 10 years of age (Mage = 8.34) participated in monthly physical activity and nutritional events during a 9-month academic year. The children's nutritional knowledge, number of different physical activities, fitness level, dietary habits, waist circumference, BMI percentile, and percentage body fat were measured pre- and postintervention. Changes on these measures were compared to students in a school employing the school system's standard health curriculum. Regression analyses with residualized change scores revealed that the intervention school showed statistically significant improvement in percentage body fat, physical activity, performance on fitness tests, and dietary habits compared to the control school. There was no evidence of differences in outcomes based on gender or ethnicity/race. With rates of obesity and overweight reaching 50% in southern rural communities, intervening early in development may offer the best outcome because of the difficulties with changing lifestyle behaviors later in adulthood. A population-based approach is recommended over a targeted approach to cultivate a culture of healthy lifestyle behaviors when children are developing their health-care habits. Evidence suggests that both boys and girls, and African-American and white children can benefit equally from such interventions.     

Ecosystem-based assessment of a prawn fishery in coastal Kenya using ecological indicators

The study aimed to describe and assess indicators that can potentially contribute to the development of Ecosystem-based Approach to Fisheries Management (EAFM) of prawn stocks in the Malindi-Ungwana Bay, the most productive coastal ecosystem in Kenya. A comprehensive EAFM is required to holistically manage fisheries resources and their associated habitats. The study assessed ecological indicators based on objectives of harvest sustainability and biodiversity conservation. Analyses were performed on data sourced from the State Department of Fisheries, and research databases. Trends in historical landings (1985–2010) of penaeid shrimps from the Malindi-Ungwana Bay were analyzed using LOWESS. Number-size spectra analysis was used to assess the exploitation status of the shrimps, while biomass-trophic level spectra (BTLS) analysis was applied as a potential tool for analyzing multifactor effects on the bay. IndiSeas-based ecosystem indicators were used to assess impact of the prawn trawl fishery on biodiversity of the bay. Results indicate long-term series with two peaks (1997 and 2000) in historical landings of penaeid shrimps and a monotonous decline in catches during 2002–2010. Slopes of number-size spectra suggested increased fishing mortality with time (2008–2012), while patterns of intercepts indicated a general increase in fisheries productivity of the bay. BTLS analysis using demersal fish survey and fish by-catch data suggested reduced levels of biomass across trophic levels and a temporal decline in trophic levels of fish species caught, however, the short time span constrains robust conclusions from the BTLS analysis. Biodiversity and conservation based indicators (e.g. fish sizes, trophic levels and proportion of predators in catches) adopted from the IndiSeas program showed the Malindi-Ungwana Bay to be ecologically degraded. There is need to initiate long-term monitoring programs to strengthen temporal scale of analysis of the datasets and to support use of ecological indicators for resource management and development of an EAFM in data-poor WIO countries.     

Assessing the impact of school-based mentoring: Common problems and solutions associated with evaluating nonprescriptive youth development programs

ABSTRACT

Like many youth development programs, most youth mentoring programs do not have prescribed practices that target specific outcomes. Because the construct of mentoring represents a broad range of potential activities, researchers face a conundrum when making generalizable causal inferences about the effects of this and similar services. On the one hand, researchers cannot make valid experimental inferences if they do not describe what they manipulate. On the other hand, experiments that include prescribed protocols do not generalize to most mentoring programs. In most cases, researchers conducting school-based mentoring program evaluations err on the side of not sufficiently specifying treatment constructs, which limits the field’s ability to make practically or theoretically useful inferences about this service. We discuss this reality in light of the fundamental logic of the experimental design and suggest several possible solutions to this conundrum. Our goal is to empower researchers to adequately specify treatments while still preserving the treatment construct validity of this and similar interventions.     

The practical challenges of evaluating a blanket emergency feeding programme in northern Kenya

A blanket supplementary feeding programme for young children was implemented for four months in five northern districts of Kenya from January 2010 because of fears of food insecurity exacerbated by drought. An attempt to evaluate the impact of the food on children's anthropometric status was put in place in three districts. The main aim of the analysis was to assess the quality of the data on the cohort of children studied in the evaluation and to propose methods by which it could be improved to evaluate future blanket feeding programmes. Data on the name, age, sex, weight and height of a systematic sample of children recruited at 61 food distribution sites were collected at the first, second and third rounds and again at an extra, fifth food distribution, offered only to the evaluation subjects. Of the 3,544 children enrolled, 483 (13.63%) did not collect a fifth ration. Of the 2,640 children who were considered by their name to be the same at the first and fifth food distribution (13% were different), data on only 902 children (34.17%) were considered acceptable based on their age (an arbitrary ±3 months different) and their length or height (between >-1 or ≤4 cm different) at the two instances they were seen. Data on nearly two thirds of children were of questionable quality. The main reasons for the poor quality data were inconsistencies in estimating age or because caretakers may have brought different children. Recommendations are made about how to improve data quality including ensuring that entry to a blanket feeding programme is clearly based on height, not age, to avoid misreporting age; careful identification of subjects at all contacts; and using well-trained, specialist evaluation staff.     

Long-term outcomes of school-based treatment for control of urinary schistosomiasis: a review of experience in Coast Province, Kenya

Urinary schistosomiasis remains a significant burden for Africa and the Middle East. The success of population-based control programs will depend on their impact, over many years, on Schistosoma haematobium reinfection and associated disease. In a multi-year (1984-1992) control program in Kenya, we examined risk for S. haematobium reinfection and late disease during and after annual school-based treatment. In this setting, long-term risk of new infection was independently associated with location, age, hematuria, and incomplete treatment, but not with sex or frequency of water contact. Thus, very local environmental features and age-related factors played an important role in S. haematobium transmission, such that population-based control programs should optimally tailor their efforts to local conditions on a village-by-village basis. In 2001-2002, the late benefits of earlier participation in school-based antischistosomal therapy were estimated in a cohort of formerly-treated adult residents compared to never-treated adults from the same villages. Among age-matched subjects, current infection prevalence was lower among those who had received remote therapy. In addition, prevalence of bladder abnormality was lower in the treated group, who were free of severe bladder disease. Treatment of affected adults resulted in rapid resolution of infection and any detectable bladder abnormalities. We conclude that continued treatment into adulthood, as well as efforts at long-term prevention of infection (transmission control) are necessary to achieve optimal morbidity control in affected communities.     

An assemblage of wintering waders in coastal Kenya: activity budget and habitat use

To contribute to the poorly known ecology of Palearctic immigrant waders in East Africa, we studied the foraging system (roosting and foraging behaviours, 24‐h activity rhythm, time‐activity budget and habitat use) of eleven wader species overwintering on the Kenyan coast. The waders congregated in communal roosts and completely overlapped in their foraging rhythms, which in this tidal environment were completely determined by tides, and which were independent of the dark/light cycle. All species, both tactile and visual foragers, fed both by day and by night. This study, along with similar findings for other areas of the Palaeotropics, shows that wader activity throughout the 24‐h day is essentially uniform, and is only slightly influenced by the dark/light cycle, but is modified by tidal levels. The total time devoted to feeding by each wader species was related to their body mass. Each species used a specific micro‐habitat for foraging.     

Notes on the ecology of a suburban population of Rainbow lizards in coastal Kenya

Aspects of the ecology of a suburban population of rainbow lizards, Agama agama Linnaeus 1758, have been studied in Malindi, a coastal locality of SE Kenya. Four different family groups were monitored on a wall transect 120 m long. Each group constituted a dominant male (i.e. a brightly coloured and aggressive individual) and three to four adult females, but in one of the studied groups a subordinate male was also seen. Both sexes were active in the morning, and peak activity fell between 10.00 and 11.30 hours. Dominant males used elevated perches significantly more often than subordinate males and females. The diet consisted of terrestrial arthropods, and most of the prey eaten were beetles (6–8 mm long). The foraging strategy used by rainbow lizards was to eat small insects at very short time intervals. The lizards used sit-and-wait foraging, remaining motionless until the prey was <5 cm away. The rainbow lizards studied did not feed upon plant material.     

Outcomes and moderators of a preventive school-based mental health intervention for children affected by war in Sri Lanka: a cluster randomized trial

We aimed to examine outcomes, moderators and mediators of a preventive school-based mental health intervention implemented by paraprofessionals in a war-affected setting in northern Sri Lanka. A cluster randomized trial was employed. Subsequent to screening 1,370 children in randomly selected schools, 399 children were assigned to an intervention (n=199) or waitlist control condition (n=200). The intervention consisted of 15 manualized sessions over 5 weeks of cognitive behavioral techniques and creative expressive elements. Assessments took place before, 1 week after, and 3 months after the intervention. Primary outcomes included post-traumatic stress disorder (PTSD), depressive, and anxiety symptoms. No main effects on primary outcomes were identified. A main effect in favor of intervention for conduct problems was observed. This effect was stronger for younger children. Furthermore, we found intervention benefits for specific subgroups. Stronger effects were found for boys with regard to PTSD and anxiety symptoms, and for younger children on pro-social behavior. Moreover, we found stronger intervention effects on PTSD, anxiety, and function impairment for children experiencing lower levels of current war-related stressors. Girls in the intervention condition showed smaller reductions on PTSD symptoms than waitlisted girls. We conclude that preventive school-based psychosocial interventions in volatile areas characterized by ongoing war-related stressors may effectively improve indicators of psychological wellbeing and posttraumatic stress-related symptoms in some children. However, they may undermine natural recovery for others. Further research is necessary to examine how gender, age and current war-related experiences contribute to differential intervention effects.     

PrPs: Proteins with a purpose: Lessons from the zebrafish

The best-known attribute of the prion protein (PrP) is its tendency to misfold into a rogue isoform. Much less understood is how this misfolded isoform causes deadly brain illnesses. Neurodegeneration in prion disease is often seen as a consequence of abnormal PrP function yet, amazingly little is known about the normal, physiological role of PrP. In particular, the absence of obvious phenotypes in PrP knockout mice has prevented scientists from answering this important question. Using knockdown approaches, we previously produced clear PrP loss-of-function phenotypes in zebrafish embryos. Analysis of these phenotypes revealed that PrP can modulate E-cadherin-based cell-cell adhesion, thereby controlling essential morphogenetic cell movements in the early gastrula. Our data also showed that PrP itself can elicit homophilic cell-cell adhesion and trigger intracellular signaling via Src-related kinases. Importantly, these molecular functions of PrP are conserved from fish to mammals. Here we discuss the use of the zebrafish in prion biology and how it may advance our understanding of the roles of PrP in health and disease.Key words: PrP, zebrafish, development, cell adhesion, signaling     

Dissimilatory sulphate reduction in hypersaline coastal pans: an integrated microbiological and geochemical study

Here, we report on the spatial and temporal variation in sulphate‐reducing bacterial community structure and activity in three hypersaline coastal pans. Community structure was determined using denaturing gradient gel electrophoresis (DGGE). Cluster analysis of DGGE patterns indicated that similar microbial populations were generally found in individual pans but varied from one pan to the other. Sulphate reducing bacteria (SRB) were quantified by competitive polymerase chain reaction based on the amplification of the dsrAB genes. Cell numbers and in situ sulphate reduction activities varied between seasons and pans but in general showed low variation in depth. Sulphate reduction activity was not correlated with microbial population size indicating that community composition is relevant for specific microbial processes. Principal component analysis coupled with correlation analyses suggested that salinity, sulphate concentration, C/N ratio and pH were the most important factors in explaining variations in SRB community composition. Most sequences derived from DGGE amplicons belonged to members of the Desulfobacteraceae and Desulfohalobiaceae families.     

Dragonfly communities in coastal habitats of Kenya: indication of biotope quality and the need of conservation measures

This study highlights the species diversity of Odonata from coastal forests in southern Kenya, identifying indicator species for certain habitat types and emphasising the importance of conserving the last remaining coastal forest areas. A total of 78 species were recorded from coastal habitats in southern Kenya in this study; five species for the first time in eastern Africa. Dragonfly communities relative to different habitat types from indigenous forest to cultivated landscapes are described and compared. The forest species are often confined to coastal forests of East Africa. They are stenotopic and highly sensitive to disturbance. With increasing habitat disturbance the species richness increases at first, but most of the colonisers are eurytopic species that are common and widely distributed in Africa. The species assemblages between different habitat types in the disturbed landscape are more or less the same; the -diversity is much lower than in different habitat types of the natural coastal landscape. In the end, management implications are briefly discussed.     

Connectivity of a large embayment and coastal fishery: spawning aggregations in one bay source local and broad-scale fishery replenishment

Ichthyoplankton sampling and otolith chemistry were used to determine the importance of transient spawning aggregations of snapper Chrysophrys auratus (Sparidae) in a large embayment, Port Phillip Bay (PPB), Australia, as a source of local and broad-scale fishery replenishment. Ichthyoplankton sampling across five spawning seasons within PPB, across the narrow entrance to the bay and in adjacent coastal waters, indicated that although spawning may occur in coastal waters, the spawning aggregations within the bay were the primary source of larval recruitment to the bay. Otolith chemical signatures previously characterized for 0+ year C. auratus of two cohorts (2000 and 2001) were used as the baseline signatures to quantify the contribution that fish derived from reproduction in PPB make to fishery replenishment. Sampling of these cohorts over a 5 year period at various widely dispersed fishery regions, combined with maximum likelihood analyses of the chemistry of the 0+ year otolith portions of these older fish, indicated that C. auratus of 1 to 3+ years of age displayed both local residency and broad-scale emigration from PPB to populate coastal waters and an adjacent bay (Western Port). While the PPB fishery was consistently dominated (>70%) by locally derived fish irrespective of cohort or age, the contribution of fish that had originated from PPB to distant populations increased with age. At 4 to 5+ years of age, when C. auratus mature and fully recruit to the fishery, populations of both cohorts across the entire central and western Victorian fishery, including two major embayments and c. 800 km of coastal waters, were dominated (>70%) by fish that had originated from the spawning aggregations and nursery habitat within PPB. Dependence of this broadly dispersed fishery on replenishment from heavily targeted spawning aggregations within one embayment has significant implications for management and monitoring programmes.     

Potential rates and pathways of microbial nitrate reduction in coastal sediments

Nitrate reduction plays a key role in the biogeochemical dynamics and microbial ecology of coastal sediments. Potential rates of nitrate reduction were measured on undisturbed sediment slices from two eutrophic coastal environments using flow-through reactors (FTR). Maximum potential nitrate reduction rates ranged over an order of magnitude, with values of up to 933 nmol cm(-3) h(-1), whereas affinity constants for NO(3) (-) fell mostly between 200 and 600 microM. Homogenized sediment slurries systematically yielded higher rates of nitrate reduction than the FTR experiments. Dentrification was the major nitrate removal pathway in the sediments, although excess ammonium production indicated a contribution of dissimilatory nitrate reduction to ammonium under nitrate-limiting conditions.     

An integrated model for evaluating hydrology,hydrodynamics, salinity and vegetation cover in a coastal desert wetland

An integrated model describing hydrology, hydrodynamics, salt dynamics and vegetation was developed to predict the evolution of the Ciénega de Santa Clara, a non-tidal, anthropogenic wetland located in the Colorado River Delta. The Ciénega, an important part of the Delta ecosystem, is supported by saline groundwater from the U.S. that is sent to Mexico to control salinity in the U.S. The future of this water source is uncertain, and thus, the model was developed to predict how the Ciénega would respond to changes in the quantity and salinity of its inflow. Over the calibration period, 1993–2007, modeled results of wetland surface area, the fraction of the wetland covered in vegetation and salinity concentrations compare well to actual data. The model shows that between 1993 and 2007 evapotranspiration rates range from 0 to 8 mm/day, wetland surface area increases 44% from 4500 to 6500 ha, the fraction of the wetland covered in vegetation decreases slightly from 0.92 to 0.88, and the mean salinity concentration in the wetland increases from 3100 to 6700 ppm. The model was used to run nine hypothetical scenarios, representing the range of inflow quantity and salinity to the Ciénega that could occur if the source of the inflow is altered, including the possible re-opening of the Yuma Desalting plant. Model results show that the Ciénega ecosystem is more sensitive to changes in salinity than to changes in flow. However, in almost all cases, an increase in salinity and/or a decrease in flow would cause a significant decrease in vegetation cover, compromising a large portion of the habitat currently available to wildlife at the Ciénega.     

Species richness and parasitism in an assemblage of parasitoids attacking maize stem borers in coastal Kenya

Abstract. 1. Parasitoids were reared from four species of lepidopteran stem borer collected in maize in southern coastal Kenya from 1992 to 1999. The stem borers included three native species, Sesamia calamistis Hampson, Busseola fusca Fuller, and Chilo orichalcociliellus (Strand), and one exotic borer, Chilo partellus (Swinhoe). A total of 174 663 caterpillars was collected, of which 12 645 were parasitised.
2. Twenty-six primary parasitoid species were reared from the exotic borer, C. partellus , indicating a rapid accumulation of native parasitoids on the alien borer.
3. The three most abundant parasitoids were the larval parasitoids Cotesia sesamiae Cameron, Cotesia flavipes (Cameron), and the pupal parasitoid Pediobius furvus Gahan. The pupal parasitoid Dentichasmias busseolae Heinrich and the larval parasitoid Goniozus indicus Ashmead were also common. All used an ingress-and-sting method of attack.
4. Cotesia flavipes , introduced into Kenya in 1993, was found in all seasons from 1997 onwards, and has become the most abundant stem borer larval parasitoid in the area. A native congener, Cotesia sesamiae , appeared in all seasons from 1992 to 1999. Together, these two parasitoids accounted for 83.3% of the parasitised borers.
5. Thirty parasitoid species were recovered in Kilifi district, 27 in Kwale, and 15 in Taita Taveta. Parasitism was much greater in Taita Taveta district than in Kilifi or Kwale districts.