Operative strategy for fistula-in-ano without division of the anal sphincter

We would like to thank Mr ER MacDonald for his contribution in data collection during the early years of the study. The material in this paper was presented as a poster at the annual meeting of the American Society of Colon and Rectal Surgeons held in Vancouver, Canada, May 2011.Peer reviewedPublisher PD

Computer-aided verification in mechanism design

In mechanism design, the gold standard solution concepts are dominant strategy incentive compatibility and Bayesian incentive compatibility. These solution concepts relieve the (possibly unsophisticated) bidders from the need to engage in complicated strategizing. While incentive properties are simple to state, their proofs are specific to the mechanism and can be quite complex. This raises two concerns. From a practical perspective, checking a complex proof can be a tedious process, often requiring experts knowledgeable in mechanism design. Furthermore, from a modeling perspective, if unsophisticated agents are unconvinced of incentive properties, they may strategize in unpredictable ways. To address both concerns, we explore techniques from computer-aided verification to construct formal proofs of incentive properties. Because formal proofs can be automatically checked, agents do not need to manually check the properties, or even understand the proof. To demonstrate, we present the verification of a sophisticated mechanism: the generic reduction from Bayesian incentive compatible mechanism design to algorithm design given by Hartline, Kleinberg, and Malekian. This mechanism presents new challenges for formal verification, including essential use of randomness from both the execution of the mechanism and from the prior type distributions. As an immediate consequence, our work also formalizes Bayesian incentive compatibility for the entire family of mechanisms derived via this reduction. Finally, as an intermediate step in our formalization, we provide the first formal verification of incentive compatibility for the celebrated Vickrey-Clarke-Groves mechanism

Contribution of Direct Heating, Thermal Conduction and Perfusion During Radiofrequency and Microwave Ablation

Both radiofrequency (RF) and microwave (MW) ablation devices are clinically used for tumor ablation. Several studies report less dependence on vascular mediated cooling of MW compared to RF ablation. We created computer models of a cooled RF needle electrode, and a dipole MW antenna to determine differences in tissue heat transfer

Shared Skeletal Support in a Coral-Hydroid Symbiosis

Hydroids form symbiotic relationships with a range of invertebrate hosts. Where they live with colonial invertebrates such as corals or bryozoans the hydroids may benefit from the physical support and protection of their host's hard exoskeleton, but how they interact with them is unknown. Electron microscopy was used to investigate the physical interactions between the colonial hydroid Zanclea margaritae and its reef-building coral host Acropora muricata. The hydroid tissues extend below the coral tissue surface sitting in direct contact with the host's skeleton. Although this arrangement provides the hydroid with protective support, it also presents problems of potential interference with the coral's growth processes and exposes the hydroid to overgrowth and smothering. Desmocytes located within the epidermal layer of the hydroid's perisarc-free hydrorhizae fasten it to the coral skeleton. The large apical surface area of the desmocyte and high bifurcation of the distal end within the mesoglea, as well as the clustering of desmocytes suggests that a very strong attachment between the hydroid and the coral skeleton. This is the first study to provide a detailed description of how symbiotic hydroids attach to their host's skeleton, utilising it for physical support. Results suggest that the loss of perisarc, a characteristic commonly associated with symbiosis, allows the hydroid to utilise desmocytes for attachment. The use of these anchoring structures provides a dynamic method of attachment, facilitating detachment from the coral skeleton during extension, thereby avoiding overgrowth and smothering enabling the hydroid to remain within the host colony for prolonged periods of time

A group randomized trial of a complexity-based organizational intervention to improve risk factors for diabetes complications in primary care settings: study protocol

<p>Abstract</p> <p>Background</p> <p>Most patients with type 2 diabetes have suboptimal control of their glucose, blood pressure (BP), and lipids – three risk factors for diabetes complications. Although the chronic care model (CCM) provides a roadmap for improving these outcomes, developing theoretically sound implementation strategies that will work across diverse primary care settings has been challenging. One explanation for this difficulty may be that most strategies do not account for the complex adaptive system (CAS) characteristics of the primary care setting. A CAS is comprised of individuals who can learn, interconnect, self-organize, and interact with their environment in a way that demonstrates non-linear dynamic behavior. One implementation strategy that may be used to leverage these properties is practice facilitation (PF). PF creates time for learning and reflection by members of the team in each clinic, improves their communication, and promotes an individualized approach to implement a strategy to improve patient outcomes.</p> <p>Specific objectives</p> <p>The specific objectives of this protocol are to: evaluate the effectiveness and sustainability of PF to improve risk factor control in patients with type 2 diabetes across a variety of primary care settings; assess the implementation of the CCM in response to the intervention; examine the relationship between communication within the practice team and the implementation of the CCM; and determine the cost of the intervention both from the perspective of the organization conducting the PF intervention and from the perspective of the primary care practice.</p> <p>Intervention</p> <p>The study will be a group randomized trial conducted in 40 primary care clinics. Data will be collected on all clinics, with 60 patients in each clinic, using a multi-method assessment process at baseline, 12, and 24 months. The intervention, PF, will consist of a series of practice improvement team meetings led by trained facilitators over 12 months. Primary hypotheses will be tested with 12-month outcome data. Sustainability of the intervention will be tested using 24 month data. Insights gained will be included in a delayed intervention conducted in control practices and evaluated in a pre-post design.</p> <p>Primary and secondary outcomes</p> <p>To test hypotheses, the unit of randomization will be the clinic. The unit of analysis will be the repeated measure of each risk factor for each patient, nested within the clinic. The repeated measure of glycosylated hemoglobin A1c will be the primary outcome, with BP and Low Density Lipoprotein (LDL) cholesterol as secondary outcomes. To study change in risk factor level, a hierarchical or random effect model will be used to account for the nesting of repeated measurement of risk factor within patients and patients within clinics.</p> <p>This protocol follows the CONSORT guidelines and is registered per ICMJE guidelines:</p> <p>Clinical Trial Registration Number</p> <p>NCT00482768</p

Alcohol Consumption Among Older Adults in Primary Care

BACKGROUND: Alcohol misuse is a growing public health concern for older adults, particularly among primary care patients. OBJECTIVES: To determine alcohol consumption patterns and the characteristics associated with at-risk drinking in a large sample of elderly primary care patients. DESIGN: Cross-sectional analysis of multisite screening data from 6 VA Medical Centers, 2 hospital-based health care networks, and 3 Community Health Centers. PARTICIPANTS: Patients, 43,606, aged 65 to 103 years, with scheduled primary care appointments were approached for screening; 27,714 (63.6%) consented to be screened. The final sample of persons with completed screens comprised 24,863 patients. MEASUREMENTS: Quantity and frequency of alcohol use, demographics, social support measures, and measures of depression/anxiety. RESULTS: Of the 24,863 older adults screened, 70.0% reported no consumption of alcohol in the past year, 21.5% were moderate drinkers (1–7 drinks/week), 4.1% were at-risk drinkers (8–14 drinks/week), and 4.5% were heavy (>14 drinks/week) or binge drinkers. Heavy drinking showed significant positive association with depressive/anxiety symptoms [Odds ratio (OR) (95% CI): 1.79 (1.30, 2.45)] and less social support [OR (95% CI): 2.01 (1.14, 2.56)]. Heavy drinking combined with binging was similarly positively associated with depressive/anxiety symptoms [OR (95%): 1.70 (1.33, 2.17)] and perceived poor health [OR (95% CI): 1.27 (1.03, 1.57)], while at-risk drinking was not associated with any of these variables. CONCLUSIONS: The majority of participants were nondrinkers; among alcohol users, at-risk drinkers did not differ significantly from moderate drinkers in their characteristics or for the 3 health parameters evaluated. In contrast, heavy drinking was associated with depression and anxiety and less social support, and heavy drinking combined with binge drinking was associated with depressive/anxiety symptoms and perceived poor health

Effects of an interactive CD-program on 6 months readmission rate in patients with heart failure – a randomised, controlled trial [NCT00311194]

BACKGROUND: Disease-management programmes including patient education have promoted improvement in outcome for patients with heart failure. However, there is sparse evidence concerning which component is essential for success, and very little is known regarding the validity of methods or material used for the education. METHODS: Effects of standard information to heart failure patients given prior to discharge from hospital were compared with additional education by an interactive program on all-cause readmission or death within 6 months. As a secondary endpoint, patients' general knowledge of heart failure and its treatment was tested after 2 months. RESULTS: Two hundred and thirty patients were randomised to standard information (S) or additional CD-ROM education (E). In (S) 52 % reached the endpoint vs. 49 % in (E). This difference was not significant. Of those who completed the questionnaire (37 %), patients in (E) achieved better knowledge and a marginally better outcome. CONCLUSION: The lack of effect on the readmission rate could be due to an insufficient sample size but might also indicate that in pharmacologically well-treated patients there is little room for altering the course of the condition. As there was some indication that patients who knew more about their condition might fare better, the place for intensive education and support of heart failure patients has yet to be determined

Improved Measurement of the Pseudoscalar Decay Constant fDsf_{D_{s}}

We present a new determination of the Ds decay constant, f_{Ds} using 5 million continuum charm events obtained with the CLEO II detector. Our value is derived from our new measured ratio of widths for Ds -> mu nu/Ds -> phi pi of 0.173+/- 0.021 +/- 0.031. Taking the branching ratio for Ds -> phi pi as (3.6 +/- 0.9)% from the PDG, we extract f_{Ds} = (280 +/- 17 +/- 25 +/- 34){MeV}. We compare this result with various model calculations.Comment: 23 page postscript file, postscript file also available through http://w4.lns.cornell.edu/public/CLN

Atomic force microscopy based nanoassay: A new method to study \u3b1-Synuclein-dopamine bioaffinity interactions

Intrinsically Disordered Proteins (IDPs) are characterized by the lack of well-defined 3-D structure and show high conformational plasticity. For this reason, they are a strong challenge for the traditional characterization of structure, supramolecular assembly and biorecognition phenomena. We show here how the fine tuning of protein orientation on a surface turns useful in the reliable testing of biorecognition interactions of IDPs, in particular \u3b1-Synuclein. We exploited atomic force microscopy (AFM) for the selective, nanoscale confinement of \u3b1-Synuclein on gold to study the early stages of \u3b1-Synuclein aggregation and the effect of small molecules, like dopamine, on the aggregation process. Capitalizing on the high sensitivity of AFM topographic height measurements we determined, for the first time in the literature, the dissociation constant of dopamine-\u3b1-Synuclein adducts