A family assessment based on the social relations model

One purpose of family assessment is to formulate hypotheses that can guide clinical interventions. Family assessment is based on models about family functioning. In this paper the Social Relations Model (Kenny and La Voie, 1984; SRM) is presented as such a model about family dynamics. Moreover, SRM provides statistical tools to underpin empirical hypotheses about family functioning. An SRM family assessment of a family with a child in child psychiatric care exemplifies the possibilities and limitations of this SRM approach to family assessment. The subject of the family assessment is family members' sense of influence in their family relationships

The social relations model for count data : an exploration of intergenerational co-activity within families

The social relations model (SRM) is typically used to identify sources of variance in interpersonal dispositions in families. Traditionally, it uses dyadic measurements that are obtained from a round-robin design, where each family member rates each other family member. Those dyadic measurements are mostly considered to be continuous, but we, however, wilt discuss how the SRM can be adapted to count dyadic measurements. Such SRM for count data can be formulated in the SEM-framework by viewing it as a confirmatory factor analysis (CFA), but it can also be defined in the multilevel framework. These two frameworks result in equivalent models of which the parameters can be estimated using maximum likelihood estimation or a Bayesian approach. We perform a simulation study to compare the performance of those two estimators. As an illustration, we consider intergenerational co-activity data from a block design and contrast family dynamics between non-divorced families and stepfamilies

Coking of JP-4 fuels in electrically heated metal tubes

A limited exploratory investigation of the rate of coking of four JP-4 fuels in electrically heated metal tubes was conducted in order to provide design information for fuel prevaporizers for turbojet-engine combustors. The fuels tested included two production and two minimum-quality JP-4 type fuels. The heating tube was operated at fuel pressures of approximately 500, 400, and 50 pounds per square inch. The operating fuel temperature was varied between approximately 600 degrees and 1200 degrees F

Secondary succession in an experimentally fragmented landscape: community patterns across space and time

Secondary succession reflects, at least in part, community assembly—the sequences of colonizations and extinctions. These processes in turn are expected to be sensitive to the size of the site undergoing assembly and its location relative to source pools. In this paper we describe patterns of succession over 18 years in an experimentally fragmented landscape created in eastern Kansas, USA, in 1984. The design of the experiment permits one to assess the influence of patch size and landscape position on successional dynamics. The general trajectory of succession follows that typical of succession in much of the eastern United States. In the initial years of the study, there was relatively little effect of patch size or distance to sources. Here we show that spatial effects in this system have become increasingly evident with time, as gauged both by repeated-measures ANOVA and ordination techniques. Woody plants have colonized more rapidly (per unit area) on large and nearby patches. Species richness at a local (within-quadrat) scale in general has increased, with slightly greater richness in large than in small patches later in the study. Temporal stability in community composition has generally been greater in large patches. Spatial heterogeneity in community composition has increased during succession, but with different patterns in large and small patches. This long-term experiment suggests that landscape structure influences many aspects of community structure and dynamics during succession, and that such effects become more pronounced with the passage of time

Measuring Recovery: An Adapted Brief Assessment of Mood (BAM+) Compared to Biochemical and Power Output Alterations

ObjectivesBiochemical (e.g., creatine kinase (CK)) and neuromuscular (e.g., peak power output (PPO)) markers of recovery are expensive and require specialist equipment. Perceptual measures are an effective alternative, yet most validated scales are too long for daily use.DesignThis study utilises a longitudinal multi-level design to test an adapted Brief Assessment of Mood (BAM + ), with four extra items and a 100 mm visual analogue scale to measure recovery.MethodsElite under-21 academy soccer players (N = 11) were monitored across five games with data (BAM+, CK and PPO) collected for each game at 24 hours pre, 24 hours and 48 hours post-match. Match activity data for each participant was also collected using GPS monitors on players.ResultsBAM+, CK and PPO had significant (p < .05) linear and quadratic growth curves across time and games that matched the known time reports of fatigue and recovery. Multi-level linear modelling (MLM) with random intercepts for ‘participant’ and ‘game’ indicated only CK significantly contributed to the variance of BAM+ scores (p < .05). Significant correlations (p < .01) were found between changes in BAM+ scores from baseline at 24 and 48 hours post-match for total distance covered per minute, high intensity distance covered per minute, and total number of sprints per minute.ConclusionsVisual and inferential results indicate that the BAM+ appears effective for monitoring longitudinal recovery cycles in elite level athletes. Future research is needed to confirm both the scales reliability and validity

WebSOS: Protecting Web Servers From DDoS Attacks

We present the WebSOS architecture, a mechanism for countering denial of service (DoS) attacks against web servers. WebSOS uses a combination of overlay networking, content-based routing, and aggressive packet filtering to guarantee access to a service that is targeted by a DoS attack. Our approach requires no modifications to servers or browsers, and makes use of the web proxy feature and TLS client authentication supported by modern browsers. We use a WebSOS prototype to conduct a preliminary performance evaluation both on the local area network and over the Internet using PlanetLab, a testbed for experimentation with network overlays. We determine the end-to-end latency imposed by the architecture to increase by a factor of 5 on average. We conclude that this overhead is reasonable in the context of a determined DoS attack