No relationship between fecundity and annual reproductive rate in bony fish

Background. There is still a widespread notion that bony fishes with high fecundities are more productive and therefore more resistant to overexploitation. The purpose of this study was to formally explore the relationship between fecundity and reproductive success expressed as maximum annual reproductive rate, i.e. the number of new spawners produced by existing spawners at low population densities. Material and methods. We used maximum annual reproductive rate from a recent study covering 49 species of bony fish; we used fecundity estimates from the published literature. Results. We found no significant relationship between fecundity (ranging from 368 to 10 million eggs) and maximum annual reproductive rate (ranging from 0.4 to 13.5 replacement spawners). Conclusion. Fecundity in oviparous bony fish without parental care has no relation with reproductive success. Apparently high fecundity in bony fish has evolved to counterbalance pre-adult mortality, as indicated by the fact that variance in fecundity is 3 orders of magnitude larger than variance in annual reproductive rate

Contact force sensing in ablation of ventricular arrhythmias using a 56-hole open-irrigation catheter: a propensity-matched analysis.

PURPOSE: The effect of adding contact force (CF) sensing to 56-hole tip irrigation in ventricular arrhythmia (VA) ablation has not been previously studied. We aimed to compare outcomes with and without CF sensing in VA ablation using a 56-hole radiofrequency (RF) catheter. METHODS: A total of 164 patients who underwent first-time VA ablation using Thermocool SmartTouch Surround Flow (TC-STSF) catheter (Biosense-Webster, Diamond Bar, CA, USA) were propensity-matched in a 1:1 fashion to 164 patients who had first-time ablation using Thermocool Surround Flow (TC-SF) catheter. Patients were matched for age, gender, cardiac aetiology, ejection fraction and approach. Acute success, complications and long-term follow-up were compared. RESULTS: There was no difference between procedures utilising either TC-SF or TC-STSF in acute success (TC-SF: 134/164 (82%), TC-STSF: 141/164 (86%), p = 0.3), complications (TC-SF: 11/164 (6.7%), TC-STSF: 11/164 (6.7%), p = 1.0) or VA-free survival (TC-SF: mean arrhythmia-free survival time = 5.9 years, 95% CI = 5.4-6.4, TC-STSF: mean = 3.2 years, 95% CI = 3-3.5, log-rank p = 0.74). Fluoroscopy time was longer in normal hearts with TC-SF (19 min, IQR: 14-30) than TC-STSF (14 min, IQR: 8-25; p = 0.04). CONCLUSION: Both TC-SF and TC-STSF catheters are safe and effective in treating VAs. The use of CF sensing catheters did not improve safety or acute and long-term outcomes, but reduced fluoroscopy time in normal heart VA

International Environmental Agreements under Uncertainty: Does the Veil of Uncertainty Help?

Na and Shin (1998) showed that the veil of uncertainty can be conducive to the success of self-enforcing international environmental agreements. Later papers confirmed this negative conclusion about the role of learning. In the light of intensified research efforts worldwide to reduce uncertainty about the environmental impact of emissions and the cost of reducing them, this conclusion is intriguing. The purpose of this paper is threefold. First, we analyze whether the result carries over to a more general setting without restriction on the number of players and which considers not only no and full learning but also partial learning. Second, we test whether the conclusion also holds if there is uncertainty about abatement costs instead of uncertainty about the benefits from global abatement. Third, we propose a transfer scheme that mitigates the possible negative effect of learning and which may even transform it into a positive effect.transnational cooperation, self-enforcing international environmental agreements, uncertainty, learning

Evaluating the Effect of Neuraxial Analgesia on External Cephalic Version Success

Abstract Background: External cephalic version (ECV) can be a helpful procedure in attempts to decrease the overall cesarean section rate. ECV involves the application of external pressure to the pregnant woman’s abdomen in attempts to turn the fetus to a vertex presentation and allow for subsequent vaginal delivery. Tocolytics are routinely used to increase ECV success rates, and neuraxial analgesia has been presented as another adjunct to increase overall success. The purpose of this quality improvement project is to evaluate the effect neuraxial analgesia may have on ECV success rates. Methods: Patients scheduled for ECV between the dates of January 2020 and September 2021 were reviewed. Data collected includes patient age, BMI, gestational age, success of ECV and use of neuraxial analgesia (epidural anesthesia). Results: Of the 21 patients, 6 (29%) were found to be vertex on their scheduled ECV date. Six (29%) patients who did not have an epidural failed ECV. Four (19%) patients who had an epidural failed ECV. Five (24%) patients who had an epidural had a successful ECV. Interestingly, no patients had a successful ECV without an epidural. Conclusion: No attempts at ECV were successful without an epidural in the 21 patient charts reviewed. Further evaluation through expanded chart review to increase the sample size would allow for meaningful statistical evaluation of this salient finding

Endoscopic Surgery for Third Ventricular Colloid Cysts in the Absence of Hydrocephalus- a feasibility study

Purpose: The aim of this study was to investigate the feasibility and effectiveness of endoscopic neurosurgery for patients with third ventricular colloid cysts without ventriculomegaly.Methods: Seventy-one patients with third ventricular colloid cysts were identified and recruited to this study. Eighteen of these patients did not have concomitant hydrocephalus and underwent primary endoscopic surgery for cyst resection. The surgical technique, the success rate, and patients’ outcome were assessed and compared with 53 hydrocephalic patients who underwent similar procedures.Results: The ventricular compartments were successfully cannulated and gross total resectin of the colloid cysts was achieved in all patients. There were no operative complications related to the endoscopic procedure. Two patients required subsequent intervention for hydrocephalus. The success rate for endoscopic surgery in non-hydrocephalic patients was similar to its value in patients with hydrocephalus.Conclusion: Endoscopic resection of third ventricular colloid cyst in patients without hydrocephalus seems to be feasible, effective and not contraindicated

Mathematics Course Placement Using Holistic Measures: Possibilities for Community College Students.

Background/Context: Most community colleges across the country use a placement test to determine students’ readiness for college-level coursework, yet these tests are admittedly imperfect instruments. Researchers have documented significant problems stemming from overreliance on placement testing, including placement error and misdiagnosis of remediation needs. They have also described significant consequences of misplacement, which can hinder the educational progression and attainment of community college students. Purpose/Objective/Research Question/Focus of Study: We explore possibilities for placing community college students in mathematics courses using a holistic approach that considers measures beyond placement test scores. This includes academic background measures, such as high school GPA and math courses taken, and indicators of noncognitive constructs, such as motivation, time use, and social support. Setting: The study draws upon administrative data from a large urban community college district in California that serves over 100,000 students each semester. The data enable us to link students’ placement testing results, survey data, background information, and transcript records. Research Design: We first use the supplemental survey data gathered during routine placement testing to conduct predictive exercises that identify severe placement errors under existing placement practices. We then move beyond prediction and evaluate student outcomes in two colleges where noncognitive indicators were directly factored into placement algorithms. Findings/Results: Using high school background information and noncognitive indicators to predict success reveals as many as one quarter of students may be misassigned to their math courses by status quo practices. In our subsequent analysis we find that students placed under a holistic approach that considered noncognitive indicators in addition to placement test scores performed no differently from higher scoring peers in the same course. Conclusions/Recommendations: The findings suggest a holistic approach to mathematics course placement may improve placement accuracy and provide access to higher level mathematics courses for community college students without compromising their likelihood of success

Efficacy of tracheal tube introducers and stylets for endotracheal intubation in the prehospital setting:a systematic review and meta‑analysis

PURPOSE: Tracheal tube introducers and stylets remain some of the most widely used devices for aiding practitioners in performing endotracheal intubation (ETI). The purpose of this systematic review is to evaluate the efficacy of tracheal tube introducers and stylets for ETI in the prehospital setting. METHODS: A literature search was conducted on the 2nd of March 2021 across PubMed, Embase (Ovid) and the Cochrane Central Register of Controlled Trials (CENTRAL) to identify relevant studies. Included studies had their data extracted and both a quality assessment and statistical analysis were performed. RESULTS: The summary estimate of prehospital studies with video technology showed a statistically significant increase in first pass ETI success in favour of bougies (RR 1.15, CI 1.10–1.21, p < 0.0001). The summary estimates of prehospital studies without video technology and simulation studies with and without video technology showed no statistical difference between methods for first pass or overall ETI success. Some of the highest success rates were recorded by devices that incorporated video technology. Stylets lead to a shorter time to ETI while bougies were easier to use. Neither device was associated with a higher rate of ETI complications than the other. CONCLUSION: Both tracheal tube introducers and stylets function as efficacious aids to intubation in the prehospital environment. Where video technology is available, bougies could offer a statistically significant advantage in terms of first pass ETI success. Where video technology is unavailable, a combination of clinical scenario, practitioner expertise and personal preference might ultimately guide the choice of device. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00068-021-01762-5

Comparative results of transluminal extraction coronary atherectomy in saphenous vein graft lesions with and without thrombus

AbstractObjectives. The purpose of this retrospective study was to compare the results of transluminal extraction coronary atherectomy in saphenous vein graft lesions with and without angiographic thrombus.Background. Percutaneous interventions in lesions with thrombus are associated with reduced procedural success and increased risk of complications. Use of the transluminal extraction catheter, which cuts and aspirates atheroma and thrombus, has been advocated as a potential revascularization strategy for lesions with thrombus.Methods. Baseline patient characteristics, lesion morphology, immediate angiographic results, in-hospital complications and follow-up were prospectively entered into an interventional cardiology data base. The results of transluminal extraction coronary atherectomy in saphenous vein bypass grafts with angiographic thrombus were compared with results in similar grafts without angiographic thrombus.Results. Transluminal extraction coronary atherectomy was performed in 175 patients with 183 vein graft lesions, including 59 lesions (32%) with thrombus (Group 1) and 124 (68%) without thrombus (Group 2). Compared with lesions in Group 2, lesions in Group 1 were associated with a higher incidence of baseline total occlusion, diffuse disease and abnormal Thrombolysis in Myocardial Infarction (TIMI) grade flow (p < 0.05); more severe diameter stenosis at baseline, after atherectomy and after final angiography (p < 0.05); a lower rate of clinical success (69% vs, 88%, p < 0.01); and more angiographic and clinical complications, including no reflow (p < 0.05), vascular repair (p < 0.05) and Q wave myocardial infarction (p = 0.09).Conclusions. In transluminal extraction coronary atherectomy of saphenous vein bypass grafts, the presence of thrombus is associated with more baseline lesion complexity, reduced clinical success and increased risk of no reflow, Q wave myocardial infarction and vascular repair

Short, Intermediate and Long Term Results of Ahmed Glaucoma Valve Implantation

Purpose: To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV) implantation for glaucomatous eyes in short, intermediate, and long term follow up periods.Patients and Methods:  In this retrospective study 76 eyes of 76 patients who underwent AGV insertion in Imam Hossein Medical Center, Tehran, Iran, between January 2008 and March 2017 with at least three years of followup were included. At each visit complete ophthalmic examination was performed and the success rate of surgery was assessed. Surgical success  was defined  as  5 ≤ IOP ≤ 21  mmHg  and  at  least  20 %  reduction  in  IOP without any glaucoma medication (complete success), or with the use of anti glaucoma medication (qualified success). The sum of complete and qualified success was reported as cumulative success.Results: The mean age of patients was 53.18 ± 16.92 years and the mean duration of follow up was 3.27 ± 2.36 years (range: 1-5 years). The complete surgical success rate was 20 % at 1 year, 18 % at 2 years, 16 % at 3 years, 15 % at 4 years, and 8 % at 5 years of followup and there was no medication free patient at more than 5 years followup. The cumulative success rate was 91 %, 88 %, 84 %, 80 %, and 77 % at 1 to 5 years of followup respectively.Conclusion: Ahmed glaucoma valve (AGV) implantation for glaucomatous eyes results in acceptable IOP reduction and less medication need in short, intermediate, and long term follow up periods.Key words: Glaucoma; Intraocular pressure; Ahmed glaucoma valve; Treatment outcome.