DM-PhyClus: A Bayesian phylogenetic algorithm for infectious disease transmission cluster inference

Background. Conventional phylogenetic clustering approaches rely on arbitrary cutpoints applied a posteriori to phylogenetic estimates. Although in practice, Bayesian and bootstrap-based clustering tend to lead to similar estimates, they often produce conflicting measures of confidence in clusters. The current study proposes a new Bayesian phylogenetic clustering algorithm, which we refer to as DM-PhyClus, that identifies sets of sequences resulting from quick transmission chains, thus yielding easily-interpretable clusters, without using any ad hoc distance or confidence requirement. Results. Simulations reveal that DM-PhyClus can outperform conventional clustering methods, as well as the Gap procedure, a pure distance-based algorithm, in terms of mean cluster recovery. We apply DM-PhyClus to a sample of real HIV-1 sequences, producing a set of clusters whose inference is in line with the conclusions of a previous thorough analysis. Conclusions. DM-PhyClus, by eliminating the need for cutpoints and producing sensible inference for cluster configurations, can facilitate transmission cluster detection. Future efforts to reduce incidence of infectious diseases, like HIV-1, will need reliable estimates of transmission clusters. It follows that algorithms like DM-PhyClus could serve to better inform public health strategies

Structural Behavior of Cold-formed Steel Header Beams for Residential Construction

The purpose of this experimental and analytical study was to observe the structural behavior of cold-formed steel header beams subject to a combined bending and interior-one-flange loading (IOF) condition as typically occurs in residential construction. This study focussed on the IOF loading of both back-to-back (I-beam) and box-beam configurations as specified in the Prescriptive Method for Residential Cold-Formed Steel Framing - Second Edition. Past research conducted in the area of web crippling strength, bending strength and flange buckling of cold-formed steel members was reviewed and is discussed. The data obtained from the experimental study was analyzed and evaluated to determine the interaction between bending and web crippling for the loading configurations used. The findings of this pilot study were used to define future research needed to establish design methodologies for residential header beam construction. Because this was a pilot study and was limited in the number of test specimens, no new design equations or recommendations were developed

Food production, distribution and processing in Cornwall and the Isles of Scilly

Cornwall Taste of the West; Cornwall Agricultural Counci

Analysis of Conventionally Framed Hip Roofs Using Cold-formed Steel Members

Cold-formed steel is continuing to increase in popularity in the residential construction market and is gaining an increasing market share compared with other construction materials. Conventionally framed hip roof construction uses rafters, ridge members, hip members and ceiling joists but does not include any supplemental interior supports or collar ties between rafters. Conventional framing has traditionally been used in light framed timber structures and more recently in roofs framed with cold-formed steel members. based upon a review of building codes, specifications and standards, it was determined that analysis and design of rafters and hip members for conventional hip roof framing does not typically consider axial forces in rafters or hip members. This paper investigates the behavior of conventionally framed coldformed steel roof framing members using elastic, finite element analysis methods. the roof system as a whole was considered in the analysis, including the contribution of the roof sheathing and ceiling joists. an analysis of members which does not consider any strength contribution from sheathing was conducted and shows that depending on the slope of the roof, axial forces developed in these members can be significant and should not be ignored. Alternatively, when roof sheathing is considered to act in combination with other framing members, the axial forces in the rafter and hip members are reduced and bending moment in the hip members are significantly reduced. This study indicates that conventional roof framing behavior can be predicted more accurately by considering the entire roof system, including sheathing, rather than as individual members

Evaluation of the Flexural Strength of Cold-formed Steel Studs with Embossed Flanges

New advances and improvements in the manufacture of cold-formed steel shapes are continually being made. One such advancement in the manufacturing of steel studs is flange embossing, a technique used to facilitate the installation of drywall screws into the stud flange. Currently, embossed flanges are not specifically addressed in the North American Specification for the Design of Cold-Formed Steel Structural Members (AISI S100), thereby drawing into question the use of current design equations from being used to calculate member properties for an embossed stud. A limited experimental investigation was undertaken to determine if light flange embossing affects the nominal flexural strength of cold-formed steel studs. Studs with embossed flanges were tested in bending and their actual flexural strength was determined. This data was then compared with the nominal flexural strength without embossing calculated using AISI S100-07 equations. The findings indicate that light flange embossing does not adversely affect the bending strength of the stud either negatively or positively and therefore, based on the scope of this study, the equations in AISI S100-07 for nominal flexural strength can be applied to lightly embossed stud

The check-up: in-person, computerized, and telephone adaptations of motivational enhancement treatment to elicit voluntary participation by the contemplator

Countless barriers come between people who are struggling with substance abuse and those charged with providing substance abuse treatment. The check-up, a form of motivational enhancement therapy, is a harm reduction intervention that offers a manner of supporting individuals by lowering specific barriers to reaching those who are untreated. The check-up was originally developed to reach problem drinkers who were neither seeking treatment nor self-initiating change. The intervention, marketed as an opportunity to take stock of one's experiences, involves an assessment and personalized feedback delivered with a counseling style termed motivational interviewing. Check-ups can be offered in care settings to individuals who, as a result of screening, manifest risk factors for specific disorders such as alcoholism. They can also be free-standing and publicized widely to the general public. This paper will discuss illustrations of in-person, computerized, in-school, and telephone applications of the free-standing type of check-up with reference to alcohol consumers, adult and adolescent marijuana smokers, and gay/bisexual males at risk for sexual transmission of HIV. The paper's major focus is to highlight how unique features of each application have the potential of reducing barriers to reaching specific at-risk populations. Also considered are key policy issues such as how check-up services can be funded, which venues are appropriate for the delivery of check-up interventions, pertinent competency criteria in evaluating staff who deliver this intervention, how marketing can be designed to reach contemplators in untreated at-risk populations, and how a check-up's success ought to be defined