Phase-stabilized, 1.5-W frequency comb at 2.8 to 4.8 micron

We present a high-power optical parametric oscillator-based frequency comb in the mid-infrared wavelength region using periodically poled lithium niobate. The system is synchronously pumped by a 10-W femtosecond Yb:fiber laser centered at 1.07 um and is singly resonant for the signal. The idler (signal) wavelength can be continuously tuned from 2.8 to 4.8 um (1.76 to 1.37 um) with a simultaneous bandwidth as high as 0.3 um and a maximum average idler output power of 1.50 W. We also demonstrate the performance of the stabilized comb by recording the heterodyne beat with a narrow-linewidth diode laser. This OPO is an ideal source for frequency comb spectroscopy in the mid-IR.Comment: 4 figure

Factors associated with the subspecialty choices of internal medicine residents in Canada

<p>Abstract</p> <p>Background</p> <p>Currently, there are more residents enrolled in cardiology training programs in Canada than in immunology, pharmacology, rheumatology, infectious diseases, geriatrics and endocrinology combined. There is no published data regarding the proportion of Canadian internal medicine residents applying to the various subspecialties, or the factors that residents consider important when deciding which subspecialty to pursue. To address the concern about physician imbalances in internal medicine subspecialties, we need to examine the factors that motivate residents when making career decisions.</p> <p>Methods</p> <p>In this two-phase study, Canadian internal medicine residents participating in the post graduate year 4 (PGY4) subspecialty match were invited to participate in a web-based survey and focus group discussions. The focus group discussions were based on issues identified from the survey results. Analysis of focus group transcripts grew on grounded theory.</p> <p>Results</p> <p>110 PGY3 residents participating in the PGY4 subspecialty match from 10 participating Canadian universities participated in the web-based survey (54% response rate). 22 residents from 3 different training programs participated in 4 focus groups held across Canada. Our study found that residents are choosing careers that provide intellectual stimulation, are consistent with their personality, and that provide a challenge in diagnosis. From our focus group discussions it appears that lifestyle, role models, mentorship and the experience of the resident with the specialty appear to be equally important in career decisions. Males are more likely to choose procedure based specialties and are more concerned with the reputation of the specialty as well as the anticipated salary. In contrast, residents choosing non-procedure based specialties are more concerned with issues related to lifestyle, including work-related stress, work hours and time for leisure as well as the patient populations they are treating.</p> <p>Conclusion</p> <p>This study suggests that internal medicine trainees, and particularly males, are increasingly choosing procedure-based specialties while non-procedure based specialties, and in particular general internal medicine, are losing appeal. We need to implement strategies to ensure positive rotation experiences, exposure to role models, improved lifestyle and job satisfaction as well as payment schedules that are equitable between disciplines in order to attract residents to less popular career choices.</p

Microplastics in the Antarctic marine system: An emerging area of research

It was thought that the Southern Ocean was relatively free of microplastic contamination; however, recent studies and citizen science projects in the Southern Ocean have reported microplastics in deep-sea sediments and surface waters. Here we reviewed available information on microplastics (including macroplastics as a source of microplastics) in the Southern Ocean. We estimated primary microplastic concentrations from personal care products and laundry, and identified potential sources and routes of transmission into the region. Estimates showed the levels of microplastic pollution released into the region from ships and scientific research stations were likely to be negligible at the scale of the Southern Ocean, but may be significant on a local scale. This was demonstrated by the detection of the first microplastics in shallow benthic sediments close to a number of research stations on King George Island. Furthermore, our predictions of primary microplastic concentrations from local sources were five orders of magnitude lower than levels reported in published sampling surveys (assuming an even dispersal at the ocean surface). Sea surface transfer from lower latitudes may contribute, at an as yet unknown level, to Southern Ocean plastic concentrations. Acknowledging the lack of data describing microplastic origins, concentrations, distribution and impacts in the Southern Ocean, we highlight the urgent need for research, and call for routine, standardised monitoring in the Antarctic marine system

Structuring communication relationships for interprofessional teamwork (SCRIPT): a cluster randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Despite a burgeoning interest in using interprofessional approaches to promote effective collaboration in health care, systematic reviews find scant evidence of benefit. This protocol describes the first cluster randomized controlled trial (RCT) to design and evaluate an intervention intended to improve interprofessional collaborative communication and patient-centred care.</p> <p>Objectives</p> <p>The objective is to evaluate the effects of a four-component, hospital-based staff communication protocol designed to promote collaborative communication between healthcare professionals and enhance patient-centred care.</p> <p>Methods</p> <p>The study is a multi-centre mixed-methods cluster randomized controlled trial involving twenty clinical teaching teams (CTTs) in general internal medicine (GIM) divisions of five Toronto tertiary-care hospitals. CTTs will be randomly assigned either to receive an intervention designed to improve interprofessional collaborative communication, or to continue usual communication practices.</p> <p>Non-participant naturalistic observation, shadowing, and semi-structured, qualitative interviews were conducted to explore existing patterns of interprofessional collaboration in the CTTs, and to support intervention development. Interviews and shadowing will continue during intervention delivery in order to document interactions between the intervention settings and adopters, and changes in interprofessional communication.</p> <p>The primary outcome is the rate of unplanned hospital readmission. Secondary outcomes are length of stay (LOS); adherence to evidence-based prescription drug therapy; patients' satisfaction with care; self-report surveys of CTT staff perceptions of interprofessional collaboration; and frequency of calls to paging devices. Outcomes will be compared on an intention-to-treat basis using adjustment methods appropriate for data from a cluster randomized design.</p> <p>Discussion</p> <p>Pre-intervention qualitative analysis revealed that a substantial amount of interprofessional interaction lacks key core elements of collaborative communication such as self-introduction, description of professional role, and solicitation of other professional perspectives. Incorporating these findings, a four-component intervention was designed with a goal of creating a culture of communication in which the fundamentals of collaboration become a routine part of interprofessional interactions during unstructured work periods on GIM wards.</p> <p>Trial registration</p> <p>Registered with National Institutes of Health as NCT00466297.</p

Progression to chronic atrial fibrillation after pacing: the Canadian Trial of Physiologic Pacing

AbstractOBJECTIVESThis study examined the effect of physiologic pacing on the development of chronic atrial fibrillation (CAF) in the Canadian Trial Of Physiologic Pacing (CTOPP).BACKGROUNDThe role of physiologic pacing to prevent CAF remains unclear. Small randomized studies have suggested a benefit for patients with sick sinus syndrome. No data from a large randomized trial are available.METHODSThe CTOPP randomized patients undergoing first pacemaker implant to ventricular-based or physiologic pacing (AAI or DDD). Patients who were prospectively found to have persistent atrial fibrillation (AF) lasting greater than or equal to one week were defined as having CAF. Kaplan-Meier plots for the development of CAF were compared by log-rank test. The effect of baseline variables on the benefit of physiologic pacing was evaluated by Cox proportional hazards modeling.RESULTSPhysiologic pacing reduced the development of CAF by 27.1%, from 3.84% per year to 2.8% per year (p = 0.016). Three clinical factors predicted the development of CAF: age ≥74 years (p = 0.057), sinoatrial (SA) node disease (p < 0.001) and prior AF (p < 0.001). Subgroup analysis demonstrated a trend for patients with no history of myocardial infarction or coronary disease (p = 0.09) as well as apparently normal left ventricular function (p = 0.11) to derive greatest benefit.CONCLUSIONSPhysiologic pacing reduces the annual rate of development of chronic AF in patients undergoing first pacemaker implant. Age ≥74 years, SA node disease and prior AF predicted the development of CAF. Patients with structurally normal hearts appear to derive greatest benefits

Decision aid on radioactive iodine treatment for early stage papillary thyroid cancer - a randomized controlled trial

Abstract Background Patients with early stage papillary thyroid carcinoma (PTC), are faced with the decision to either to accept or reject adjuvant radioactive iodine (RAI) treatment after thryroidectomy. This decision is often difficult because of conflicting reports of RAI treatment benefit and medical evidence uncertainty due to the lack of long-term randomized controlled trials. Methods We report the protocol for a parallel, 2-arm, randomized trial comparing an intervention group exposed to a computerized decision aid (DA) relative to a control group receiving usual care. The DA explains the options of adjuvant radioactive iodine or no adjuvant radioactive iodine, as well as associated potential benefits, risks, and follow-up implications. Potentially eligible adult PTC patient participants will include: English-speaking individuals who have had recent thyroidectomy, and whose primary tumor was 1 to 4 cm in diameter, with no known metastases to lymph nodes or distant sites, with no other worrisome features, and who have not received RAI treatment for thyroid cancer. We will measure the effect of the DA on the following patient outcomes: a) knowledge about PTC and RAI treatment, b) decisional conflict, c) decisional regret, d) client satisfaction with information received about RAI treatment, and e) the final decision to accept or reject adjuvant RAI treatment and rationale. Discussion This trial will provide evidence of feasibility and efficacy of the use of a computerized DA in explaining complex issues relating to decision making about adjuvant RAI treatment in early stage PTC. Trial registration Clinical Trials.gov Identifier: NCT0108355

Case Fatality Rates Based on Population Estimates of Influenza-Like Illness Due to Novel H1N1 Influenza: New York City, May–June 2009

BACKGROUND: The public health response to pandemic influenza is contingent on the pandemic strain's severity. In late April 2009, a potentially pandemic novel H1N1 influenza strain (nH1N1) was recognized. New York City (NYC) experienced an intensive initial outbreak that peaked in late May, providing the need and opportunity to rapidly quantify the severity of nH1N1. METHODS AND FINDINGS: Telephone surveys using rapid polling methods of approximately 1,000 households each were conducted May 20-27 and June 15-19, 2009. Respondents were asked about the occurrence of influenza-like illness (ILI, fever with either cough or sore throat) for each household member from May 1-27 (survey 1) or the preceding 30 days (survey 2). For the overlap period, prevalence data were combined by weighting the survey-specific contribution based on a Serfling model using data from the NYC syndromic surveillance system. Total and age-specific prevalence of ILI attributed to nH1N1 were estimated using two approaches to adjust for background ILI: discounting by ILI prevalence in less affected NYC boroughs and by ILI measured in syndromic surveillance data from 2004-2008. Deaths, hospitalizations and intensive care unit (ICU) admissions were determined from enhanced surveillance including nH1N1-specific testing. Combined ILI prevalence for the 50-day period was 15.8% (95% CI:13.2%-19.0%). The two methods of adjustment yielded point estimates of nH1N1-associated ILI of 7.8% and 12.2%. Overall case-fatality (CFR) estimates ranged from 0.054-0.086 per 1000 persons with nH1N1-associated ILI and were highest for persons>or=65 years (0.094-0.147 per 1000) and lowest for those 0-17 (0.008-0.012). Hospitalization rates ranged from 0.84-1.34 and ICU admission rates from 0.21-0.34 per 1000, with little variation in either by age-group. CONCLUSIONS: ILI prevalence can be quickly estimated using rapid telephone surveys, using syndromic surveillance data to determine expected "background" ILI proportion. Risk of severe illness due to nH1N1 was similar to seasonal influenza, enabling NYC to emphasize preventing severe morbidity rather than employing aggressive community mitigation measures