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This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship’s distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

Causal effects in right-censored survival data can be formally defined as the difference in the marginal cumulative event probabilities under particular interventions. Conventional estimators, such as the Kaplan-Meier (KM), fail to consistently estimate these marginal parameters under dependent treatment assignment or dependent censoring. Several modern estimators have been developed that reduce bias under both dependent treatment assignment and dependent censoring by incorporating information from baseline and time-dependent covariates. In the present article we describe a recently developed targeted minimum loss-based estimation (TMLE) algorithm for general longitudinal data structures and present in detail its application in right-censored survival data with time-dependent covariates. The treatment-specific marginal cumulative event probability is defined via a series of iterated conditional expectations in a time-dependent counting process framework. The TMLE involves an initial estimator of each conditional expectation and sequentially updates these such that the resulting estimator solves the efficient influence curve estimating equation in the nonparametric statistical model. We describe the assumptions required for consistent estimation of statistical parameters and additional assumptions required for consistent estimation of the causal effect parameter. Using simulated right-censored survival data, the mean squared error, bias, and 95% confidence interval coverage probability of the TMLE is compared with those of the conventional KM and the inverse probability of censoring weight estimating equation, conventional maximum likelihood substitution estimator, and the double robustaugmented inverse probability of censoring weighted estimating equation. We conclude the article with estimation of the causal effect of warfarin medical therapy on the probability of “stroke or death” within a 1-year time frame using data from the ATRIA-1 observational cohort of persons with atrial fibrillation. Our results suggest that a fixed policy of warfarin treatment for all patients would result in 2% fewer deaths or strokes within 1-year as compared with a policy of withholding warfarin from all patients.

Abstract Background A hospital admission offers smokers an opportunity to quit. Smoking cessation counseling provided in the hospital is effective, but only if it continues for more than one month after discharge. Providing smoking cessation medication at discharge may add benefit to counseling. A major barrier to translating this research into clinical practice is sustaining treatment during the transition to outpatient care. An evidence-based, practical, cost-effective model that facilitates the continuation of tobacco treatment after discharge is needed. This paper describes the design of a comparative effectiveness trial testing a hospital-initiated intervention against standard care. Methods/design A two-arm randomized controlled trial compares the effectiveness of standard post-discharge care with a multi-component smoking cessation intervention provided for three months after discharge. Current smokers admitted to Massachusetts General Hospital who receive bedside smoking cessation counseling, intend to quit after discharge and are willing to consider smoking cessation medication are eligible. Study participants are recruited following the hospital counseling visit and randomly assigned to receive Standard Care or Extended Care after hospital discharge. Standard Care includes a recommendation for a smoking cessation medication and information about community resources. Extended Care includes up to three months of free FDA-approved smoking cessation medication and five proactive computerized telephone calls that use interactive voice response technology to provide tailored motivational messages, offer additional live telephone counseling calls from a smoking cessation counselor, and facilitate medication refills. Outcomes are assessed at one, three, and six months after hospital discharge. The primary outcomes are self-reported and validated seven-day point prevalence tobacco abstinence at six months. Other outcomes include short-term and sustained smoking cessation, post-discharge utilization of smoking cessation treatment, hospital readmissions and emergency room visits, and program cost per quit. Discussion This study tests a disseminable smoking intervention model for hospitalized smokers. If effective and widely adopted, it could help to reduce population smoking rates and thereby reduce tobacco-related mortality, morbidity, and health care costs. Trial registration United States Clinical Trials Registry NCT01177176.

Abstract Background Chronic periodontitis is an inflammatory disease of the supporting structures of the teeth. Infrared microspectroscopy has the potential to simultaneously monitor multiple disease markers, including cellular infiltration and collagen catabolism, and hence differentiate diseased and healthy tissues. Therefore, our aim was to establish an infrared microspectroscopy methodology with which to analyze and interpret molecular maps defining pathogenic processes in periodontal tissues. Methods Specific key cellular and connective tissue components were identified by infrared microspectroscopy and using a chemical imaging method. Results Higher densities of DNA, total protein and lipid were revealed in epithelial tissue, compared to the lower percentage of these components in connective tissue. Collagen-specific tissue mapping by infrared microspectroscopy revealed much higher levels of collagen deposition in the connective tissues compared to that in the epithelium, as would be expected. Thus inflammatory events such as cellular infiltration and collagen deposition and catabolism can be identified by infrared microspectroscopy. Conclusion These results suggest that infrared microspectroscopy may represent a simple, reagent-free, multi-dimensional tool with which to examine periodontal disease etiology using entirely unprocessed tissue sections.

The development of experimental models of cardiac transplantation in animals has contributed to many advances in the fields of immunology and solid organ transplantation. While the heterotopic vascularized murine cardiac transplantation model was initially utilized in studies of graft rejection using combinations of mismatched inbred mouse strains, access to genetically modified strains and therapeutic modalities can provide powerful new preclinical insights. Fundamentally, the surgical methodology for this technique has not changed since its development, especially with respect to important factors such as aseptic technique, anesthesia, and analgesia, which make material impacts on postsurgical morbidity and mortality. Additionally, improvements in perioperative management are expected to provide improvements in both animal welfare and experimental outcomes. This paper reports upon a protocol developed in collaboration with a subject matter expert in veterinary anesthesia and describes the surgical technique with an emphasis on perioperative management. Additionally, we discuss the implications of these refinements and provide details on troubleshooting critical surgical steps for this procedure.

Background: In the summer of 1999, West Nile virus was recognised in the western hemisphere for the first time when it caused an epidemic of encephalitis and meningitis in the metropolitan area of New York City, NY, USA. Intensive hospital-based surveillance identified 59 cases, including seven deaths in the region. We did a household-based seroepidemiological survey to assess more clearly the public-health impact of the epidemic, its range of illness, and risk factors associated with infection., Methods: We used cluster sampling to select a representative sample of households in an area of about 7.3 km(2) at the outbreak epicentre. All individuals aged 5 years or older were eligible for interviews and phlebotomy. Serum samples were tested for IgM and IgG antibodies specific for West Nile virus., Findings: 677 individuals from 459 households participated. 19 were seropositive (weighted seroprevalence 2.6% [95% CI 1.2-4.1). Six (32%) of the seropositive individuals reported a recent febrile illness compared with 70 of 648 (11%) seronegative participants (difference 21% [0-47]). A febrile syndrome with fatigue, headache, myalgia, and arthralgia was highly associated with seropositivity (prevalence ratio 7.4 [1.5-36.6]). By extrapolation from the 59 diagnosed meningoencephalitis cases, we conservatively estimated that the New York outbreak consisted of 8200 (range 3500-13000) West Nile viral infections, including about 1700 febrile infections., Interpretation: During the 1999 West Nile virus outbreak, thousands of symptomless and symptomatic West Nile viral infections probably occurred, with fewer than 1% resulting in severe neurological disease.

Background: During an outbreak of vancomycin-resistant enterococcal (VRE) infection and colonization at a community hospital in Indianapolis, Indiana, we performed a case-control study of patients on the hospital's renal unit to determine risk factors for acquisition of VRE among this potentially high-risk patient population., Methods: Twenty-four renal patients with VRE colonization/infection (ie, case-patients) were compared by univariate and multivariate analyses with 29 renal patients with nosocomially acquired vancomycin-susceptible enterococcal infection and colonization (ie, controls)., Results: Age and length of hospitalization were similar between the VRE case-patients and the vancomycin-susceptible enterococcal control-patients, but case-patients had higher Acute Physiology and Chronic Health Evaluation II scores and received significantly greater numbers of antimicrobials and significantly more days of antimicrobials during the 60 days preceding the first positive enterococcal culture. In an assessment of the appropriateness of vancomycin use, one third of vancomycin orders were found to be inappropriate in both patient groups., Conclusions: Our data show that among renal patients, those who are severely ill and receive multiple and prolonged courses of antimicrobials are at greatest risk for acquiring VRE infection or colonization. The Centers for Disease Control and Prevention recommends that hospitals develop a comprehensive plan to prevent and control infection and colonization of patients with VRE. This plan should include prompt identification of affected patients, initiation of isolation precautions to prevent patient-to-patient transmission of VRE, and prudent use of antimicrobials, including vancomycin.

Background: Monosomy 7 and deletions of the long arm of chromosome 7 [del (7q)] are recurrent, nonrandom chromosomal abnormalities associated with both de novo and therapy-related myelodysplastic syndromes (MDS). The overall prognosis for children and adults with these chromosomal abnormalities is poor. In the current report, the authors present five children with MDS associated with monosomy 7/del(7q) who achieved spontaneous hematologic disease remission as well as a review of the literature., Methods: Five children with either de novo or treatment-related MDS who achieved spontaneous hematologic disease remission are presented. Relevant clinical, cytogenetic, and fluorescent in situ hybridization data are included., Results: All patients were boys. Three had de novo MDS whereas two others previously had received chemotherapy for another malignancy. Four patients achieved spontaneous and durable hematologic disease remission that was associated with cytogenetic disease remission in all three patients tested. The fifth patient developed a disease recurrence and died with evidence of clonal evolution after a long interval of hematologic and cytogenetic remission., Conclusions: A subset of children who develop MDS associated with monosomy 7 or del(7q) achieve spontaneous hematologic and cytogenetic improvement. Although this appears to be uncommon, further data are needed to determine the percentage of patients who improve without therapy and to define clinical characteristics that may predict this clinical outcome. These findings suggest that monosomy 7/del(7q) is insufficient to produce full leukemic transformation.

Objective: To evaluate the efficacy of patient and staff cohorting to control vancomycin-resistant enterococci (VRE) at an Indianapolis community hospital., Design: To interrupt transmission of VRE, a VRE point-prevalence survey of hospital inpatients was conducted, and VRE-infected or -colonized patients were cohorted on a single ward with dedicated nursing staff and patient-care equipment. To assess the impact of the intervention, staff compliance with contact isolation procedures was observed, and the VRE point-prevalence survey was repeated 2 months after the cohort ward was established., Results: Following the establishment of the cohort ward, VRE prevalence among all hospitalized inpatients decreased from 8.1% to 4.7% (25 positive cultures among 310 patients compared to 13 positive cultures among 276 patients, P=.14); VRE prevalence among patients whose VRE status was unknown before cultures were obtained decreased from 5.9% to 0.8% (18 positive cultures among 303 patients compared to 2 positive cultures among 262 patients, P=.002); and observed staff-patient interactions compliant with published isolation recommendations increased (5 [22%] of 23 interactions compared to 36 [88%] of 41 interactions, P<.0001)., Conclusions: Our data suggest that, in hospitals with endemic VRE or continued VRE transmission despite implementation of contact isolation measures, establishing a VRE cohort ward may be a practical and effective method to improve compliance with infection control measures and thereby to control epidemic or endemic VRE transmission.

Enterococci are an important cause of hospital-acquired infections. Since 1989, there has been an increase in the number of nosocomial enterococcal infections caused by strains resistant to vancomycin in the United States. Although many enterococcal species can colonize humans, only Enterococcus faecalis, E. faecium, E. raffinosus, and E. casseliflavus have been implicated in clusters of infection. In January 1996, the Centers for Disease Control and Prevention received a report of an outbreak of vancomycin-resistant enterococci in which 31 of 84 (36.9%) isolates were identified as E. durans. Twenty-nine isolates identified as E. durans were identified to the species level after the introduction of an automated identification system software update (Vitek gram-positive identification card, version R09.1) for the identification of species of gram-positive organisms. When seven isolates initially reported as E. durans were identified to the species level by alternate methods, they were found to be E. faecium. Subsequently, isolates identified as E. durans by the automated system were reidentified by using a rapid streptococcus test, and no further enterococcal isolate has been confirmed as E. durans. Automated microbial analysis is a potential source of error that is not easily recognized. When laboratory findings are discordant with expected clinical or epidemiologic patterns, confirmatory testing by alternate methods should be performed.

Two hundred Michigan hematologists-oncologists were sent a 34-item questionnaire designed to assess what patients should know at the time of giving consent to bone marrow transplant (BMT). Sixty-three (32%) responded to a single mailing and rated items on a 8-point scale, varying from 0 = no need to know to 7 = appreciation of consequences essential. The mean rating across items was 5.2, indicating that all items were important. Statistically, the items separated into three groups: (1) above average importance - 13 items; (2) average importance - 9 items; (3) below average importance - 12 items. Items of above average importance included the rationale for BMT and the collective risks and benefits of the process, including the patient's well-being post-transplant. Informed consent documents did not include 5/13 items of above average importance, yet 12/21 items of average and below average importance were included. Fourteen demographic variables were correlated with each item and none were significant, indicating that the ratings represent a broad consensus in the referring physician community as to what a patient should understand before consenting to BMT. The vast majority of referring physicians agreed that patients usually have an adequate understanding of BMT at the time of giving informed consent and that a fully informed patient is more likely to adhere to the treatment regimen.

Three children with Stage III neuroblastoma were treated with [125I]MIBG in a phase I toxicity study. Concepts of the treatment were: in small tumors, the absorbed dose of radiation from MIBG labeled with 131I is reduced but the absorbed dose from [125I]MIBG is less affected; and many recurrences of neuroblastoma arise from small tumors. Two patients exhibited only modest thrombocytopenia and leukopenia, the most sensitive indices of radiation toxicity, after receiving 261 and 407 mCi, and 83 and 104 rad of whole-body radiation. One patient died of progressive neuroblastoma; the other two patients have stable disease over 30 mo after treatment. Per millicurie given, [125I]MIBG imparts about one-fourth the radiation dose of [131I]MIBG to the whole body. Iodine-125-MIBG can be given in doses that impart over 100 rad of whole-body radiation and that exceed 400 mCi before toxicity becomes limiting, even in small children.