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Anastasia Andersson

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Genetic diversity is the basis for population adaptation and long-term survival, yet rarely considered in biodiversity monitoring. One key issue is the need for useful and straightforward indicators of genetic diversity. To test newly proposed indicators, we monitored genetic diversity over 40 years (1970-2010) in metapopulations of brown trout inhabiting 27 small mountain lakes representing 10 water systems in central Sweden. Three of the indicators were previously proposed for broad, international use for the Convention on Biological Diversity (CBD) context, while three others were recently elaborated for national use by a Swedish science-management effort and applied for the first time here. The Swedish indicators use molecular genetic data to monitor genetic diversity within and between populations and assess the effective population size (Ne). We used a panel of 96 SNPs and identified 29 discrete populations retained over time. Over 40 percent of the lakes harbored more than one population indicating that brown trout biodiversity hidden as cryptic, sympatric populations are more common than recognized. The Ne indicator showed values below the threshold (Ne≤500) in 20 populations with five showing Ne<100. Although statistically significant genetic diversity reductions occurred in several populations, they were mostly within proposed threshold limits. Metapopulation structure appears to buffer against diversity loss; when applying the indicators to metapopulations most indicators suggest an acceptable genetic status in all but one system. The CBD indicators agreed with the national ones but provided less detail. We propose that all indicators applied here are appropriate for monitoring genetic diversity within species.

Rowan Mott

and 6 more

Quantifying habitat quality is dependent on measuring a site’s relative contribution to population growth rate. This is challenging for studies of waterbirds, whose high mobility can decouple demographic rates from local habitat conditions and make sustained monitoring of individuals near-impossible. To overcome these challenges, biologists have used many direct and indirect proxies of waterbird habitat quality. However, consensus on what methods are most appropriate for a given scenario is lacking. We undertook a structured literature review of the methods used to quantify waterbird habitat quality, and provide a synthesis of the context-dependent strengths and limitations of those methods. Our structured search of the Web of Science database returned a sample of 398 studies, upon which our review was based. The reviewed studies assessed habitat quality by either measuring habitat attributes (e.g., food abundance, water quality, vegetation structure), or measuring attributes of the waterbirds themselves (e.g., demographic parameters, body condition, behaviour, distribution). Measuring habitat attributes, although they are only indirectly related to demographic rates, has the advantage of being unaffected by waterbird behavioural stochasticity. Conversely, waterbird-derived measures (e.g., body condition, peck rates) may be more directly related to demographic rates than habitat variables, but may be subject to greater stochastic variation (e.g., behavioural change due to presence of conspecifics). Therefore, caution is needed to ensure that the measured variable does influence waterbird demographic rates. This assumption was usually based on ecological theory rather than empirical evidence. Our review highlighted that there is no single best, universally applicable method to quantify waterbird habitat quality. Individual project specifics (e.g., time frame, spatial scale, funding) will influence the choice of variables measured. Where possible, practitioners should measure variables most directly related to demographic rates. Generally, measuring multiple variables yields a better chance of accurately capturing the relationship between habitat characteristics and demographic rates.

Paul Wembridge

and 1 more

Rationale, aim and objectives: Medication error is common and the most common form of administration error is omission. Implementation of Electronic Medication Management systems (eMMS) has been hypothesized to decrease the rate of omitted doses due to the creation of a number of forcing functions and decision support tools however there is limited evidence currently available in the literature to support this assumption. This study therefore aims to ascertain if implementation of eMMS at 2 acute metropolitan hospitals reduces the rate of omitted doses Method: A retrospective cohort study was undertaken pre and post implementation of eMMS. Patients meeting eligibility criteria had all medication charts from their admission reviewed and an omitted dose rate calculated. For each omitted dose identified; medication name, imprest availability, dispensing history, administration time and frequency were recorded. Results: 386 patients met eligibility criteria for this study (11,796 opportunities for omission). The implementation of eMMS was associated with a significant reduction in omitted doses (3.6% vs 1.8% p<0.01). Benefit was not consistent among subgroups. eMMS implementation at the hospital with the higher baseline omitted dose rate was associated with a significant reduction in omitted doses (5.8% vs 0.9% p<0.01) but not at the hospital with a lower baseline rate (2.7% vs 2.4% p=0.3). The most common times for an omitted dose to occur were 0800 (33%) and 2000 (18%). The most common frequencies for an omitted dose were daily (35%) and twice daily (32%). Conclusion: The introduction of eMMS was associated with a decrease rate of omitted doses. Greatest benefit is likely to occur in areas with a high baseline rate of omission.

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Aurélie Baliarda

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Ramsey Elsayed

and 2 more

Response to Letter to Editor Regarding: Equivalent outcomes with minimally invasive and sternotomy mitral valve repair for degenerative mitral valve disease. J Card Surg. 2021; 36:2636-43.Authors: Ramsey S. Elsayed, MD MS1, Brittany Abt, MD1, and Michael E. Bowdish, MD MS1,2Institutions and Affiliations: 1Division of Cardiac Surgery, Department of Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA2Department of Preventive Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USAAddress for Correspondence: Dr. Michael E. Bowdish, Associate Professor of Surgery and Preventive Medicine; Department of Surgery, Keck School of Medicine of USC; University of Southern California; 1520 San Pablo Street, HCC II Suite 4300; Los Angeles, CA 90033; Phone: (323)-442-5849; Email: Michael.Bowdish@med.usc.eduConflicts of Interest/Competing Interests: NoneFunding: Research reported in this publication was supported by the Department of Surgery of the Keck School of Medicine of USC. MEB is partially supported by UM1-HL11794 from the National Heart Lung and Blood Institute of the National Institutes of Health.To the editor,We would like to thank Song et. al. for their letter regarding our recent publication in the Journal of Cardiac Surgery titled “Equivalent outcomes with minimally invasive and sternotomy mitral valve repair for degenerative mitral valve disease”1. They asked some important questions and brought up valuable points that are worthy of discussion.Regarding the selection criteria we use for operative approach for mitral valve repair operations, it is primarily based on collective surgeon-patient decision making. However, patients with a previous history of cardiac surgery or peripheral vascular disease (which would render peripheral cannulation difficult), and those in need of concomitant cardiac procedures such as coronary artery bypass grafting, aortic replacement, or biatrial ablation, are not offered a minimally invasive approach. Regarding the role of artificial chordae (neochordae) in mitral valvuloplasty, we use elongated polytetrafluorethylene made of interrupted GoreTex (Gore-Tex, WL Gore and Associates, Inc., Flagstaff, AZ) sutures placed in a horizontal mattress fashion. These neochordae are routinely used to repair elongated or ruptured chordae causing mitral valve prolapse or regurgitation.2 Typically, the neochordae are used in the anterior leaflet of the mitral valve. The etiologies of degenerative mitral valve disease are comprised of myxomatous degeneration of the MV, fibroelastic deficiency including so called Barlow’s valves, and dystrophic calcification of the mitral annulus.3 While the etiologies are not mutually exclusive and may overlap, myxomatous degeneration and fibroelastic deficiencies resulting in severe, symptomatic MR were the most common indications for operation in our patient population. As mentioned by Song and colleagues, the success and durability of MVr can vary depending on etiology, particularly on how much of the valve apparatus is affected by pathology. While not examined in this paper specifically, previous papers (including Tatum et al. conducted at our institution), have demonstrated that anterior leaflet repair is significantly associated with recurrence and progression of MR after surgery, whereas isolated posterior repair is protective.3,4The operative team was similar in all cases, whereas the senior author (VAS) performed over 85% of the total procedures and nearly 100% of the minimally invasive procedures. The success rate of the minimally invasive cohort was 100% (as defined by the Society of Thoracic Surgeons). There was one conversion to conventional sternotomy in the minimally invasive cohort (.003%) for bleeding control.Finally, Song and colleagues are to be congratulated on their robotic and thoracoscopic mitral valvuloplasty results. Their 10-year total robotic mitral valve valvuloplasty results showing excellent cardiac function with 93% of patients in NYHA classes I and II.5 Furthermore, their early thoracoscopic results were very good with one operative mortality and only two reoperations demonstrating thoracoscopic mitral valvuloplasty is a technically feasible, safe, effective, and reproducible technique.6References:Bowdish ME, Elsayed RS, Tatum JM, Cohen RG, Mack WJ, Abt B, Yin V, Barr ML, Starnes VA. Equivalent outcomes with minimally invasive and sternotomy mitral valve repair for degenerative mitral valve disease. J Card Surg. 2021 Aug;36(8):2636-2643. PMID: 33908645.Bortolotti U, Milano AD, Frater RW. Mitral valve repair with artificial chordae: a review of its history, technical details, long-term results, and pathology. Ann Thorac Surg. 2012 Feb;93(2):684-91. PMID: 22153050.David, Tirone E. ”Durability of mitral valve repair for mitral regurgitation due to degenerative mitral valve disease.” Annals of cardiothoracic surgery 4.5 (2015): 417.Tatum, James M., et al. ”Outcomes after mitral valve repair: a single-center 16-year experience.” The Journal of thoracic and cardiovascular surgery 154.3 (2017): 822-830.Zhao H, Gao C, Yang M, Wang Y, Kang W, Wang R, Zhang H. Surgical effect and long-term clinical outcomes of robotic mitral valve replacement: 10-year follow-up study. J Cardiovasc Surg (Torino). 2021 Apr;62(2):162-168. PMID: 33302613.Cui H, Zhang L, Wei S, Li L, Ren T, Wang Y, Jiang S. Early clinical outcomes of thoracoscopic mitral valvuloplasty: a clinical experience of 100 consecutive cases. Cardiovasc Diagn Ther. 2020 Aug;10(4):841-848. PMCID: PMC7487400.

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