Paddlefish Management, Propagation, and Conservation in the 21st Century

<em>Abstract</em>.— Four special commercial fishing seasons (5–10 d) with mandatory check stations were used to closely monitor the harvest and exploitation of paddlefish Polyodon spathula in Ozark Lake and Pool 13 of the Arkansas River, Arkansas. The mean number of fishers (± SD) participating was 36 ± 25, and participation of statewide licensed fishers was high at 64% ± 18%. Average harvest (± SD) among seasons was 1,538 ± 652 fish and 866 ± 319 gravid females. The mean harvest rate (±SD) was 12 ± 6 fish/fisher-day effort. Exploitation estimates ranged between 19% and 40% during the 5-d seasons. Catch declined as the season progressed at Pool 13 and with a time lag at Ozark Lake. The short-term special seasons comprised 11–22% of the Arkansas statewide roe harvest for 2003, 2004, and 2006. The 5-d special season comprised 63% of the roe and 32% of the gravid females harvested for the 150-d Ozark Lake 2006–2007 season. A total of 27 citations were written for illegal activities, and bycatch mortality was a serious management concern at the 2006 Pool 13 season. Check stations provided a valuable management tool for accurately determining harvest and exploitation, and the brief special seasons allowed for controlled, monitored, and limited harvest. Illegal activities and large increases in the number of fishers entering the fishery were major threats to management for a sustainable roe fishery.

<em>Abstract</em>.—We assessed potential impacts of harvest and proposed channel modifications on the paddlefish <em>Polyodon spathula </em>fishery of Ozark Lake, Arkansas River, Arkansas. Ultrasonic telemetry was used to determine commercial and recreational exploitation rates, survival, spawning locations, and habitat use of gravid female paddlefish. Monthly searches were conducted for 40 tagged fish and we recorded 862 locations in Ozark Lake from January 2004 through December 2005. Adjacent reservoirs (i.e., Pool 13 and Lake Dardanelle) were tracked periodically, but interpool movement was not detected. Commercial fishing exploitation was determined at a mandatory check station and was estimated to be 30% during a 5-d special season. Annual recreational snag-fishing exploitation estimates were 8% (2004) and 3% (2005). Survival was different between years and was much lower the year (2004) with a commercial fishing season. Kaplan-Meier staggered-design survival estimates (±95% confidence interval [CI]) for 2004, 2005, and 2004 through 2005 were 0.60 ± 0.19, 0.92 ± 0.11, and 0.55 ± 0.18, respectively. With commercial and recreational harvests omitted from the analysis, the estimated 2-year survival rate was 0.91 ± 0.13 (±95% CI), which corresponds to 5% annual natural mortality. Gravid females migrated a median distance of 33 and 32 km in the spring of 2004 and 2005 and likely spawned in the tailwater of James W. Trimble Lock and Dam from late March to early April. Successful paddlefish reproduction was verified by capture of 23 prolarvae. Paddlefish selected tributary mouth habitat in all seasons (59% of locations). Tailwater and inundated creek channel habitats were selected in spring and summer, respectively. A navigation project to deepen the channel from 2.7 to 3.7 m will impact approximately 50% of the tailwater spawning habitat. Channel modifications (i.e., dredging and dike construction) near the mouth of the Mulberry River may disturb an important tributary mouth habitat for paddlefish where 55% of all locations were recorded. Our study identified biologically important habitats that need conservation and indicates that commercial harvest was the primary source of mortality for gravid female paddlefish in Ozark Lake.


VASA ◽  
2019 ◽  
Vol 48 (5) ◽  
pp. 413-417 ◽  
Author(s):  
Serge Couzan ◽  
Jean-François Pouget ◽  
Claire Le Hello ◽  
Céline Chapelle ◽  
Silvy Laporte ◽  
...  

Summary. Background: Theoretically progressive compression stockings, which produce a higher compression at the calf than at the ankle level, improve venous return flow without exacerbating peripheral arterial insufficiency (PAD). We aimed to evaluate the short-term tolerance of elastic progressive compression stockings on peripheral arterial vascularisation in patients with symptomatic PAD and associated mild venous insufficiency. Patients and methods: Monocentric, prospective, open pilot study of 18 patients (acceptability study, 6 x 6 plan) evaluating the short-term tolerance of progressive compression stockings (18 ± 2 mmHg at calf and 8 ± 2 mmHg at ankle level) in patients with PAD (ankle brachial index ABI > 0.60 < 0.75) and chronic venous insufficiency (C1s–C4 stages of the CEAP classification). Day 15 tolerance was evaluated by a composite primary criteria comprising: no decrease > 15 % of ABI on each side, no decrease > 15 % of toe brachial index (TBI) on each side and no decrease > 25 % of the number of active plantar flexions performed while standing. Results: The proportion of men was 77.8 %, mean age was 77.3 ± 7.5 years and no patient were diabetic. At inclusion, the mean low ABI was 0.60 ± 0.04 and the mean high ABI was 0.77 ± 0.18. The mean low TBI was 0.32 ± 0.09 and the mean high TBI 0.46 ± 0.15. The mean number of active standing plantar flexions was 33.0 ± 5.0. The majority of the patients were classified in CEAP C2s and C3 classes (class 2: 16.7 %, class C2s: 27.8 %, class C3: 44.4 %, class C4: 5.6 % and class C4s: 5.6 %). Poor tolerance occurred in no patient. By day 30, no patient had worsening of their arterial and venous symptoms. No adverse events occurred during the study. Conclusions: These results suggest a high tolerance of progressive elastic stockings (18 ± 2 mmHg at calf and 8 ± 2 mmHg at ankle level) in symptomatic PAD.


Author(s):  
Shivananda B Nayak ◽  
Dharindra Sawh ◽  
Brandon Scott ◽  
Vestra Sears ◽  
Kareshma Seebalack ◽  
...  

Purpose: i) To determine the relationship between the cardiac biomarkers ST2 and NT-proBNP with ejection fraction (EF) in heart failure (HF) patients. ii) Assess whether a superiority existed between the aforementioned cardiac markers in diagnosing the HF with reduced EF. iii) Determine the efficacy of both biomarkers in predicting a 30-day cardiovascular event and rehospitalization in patients with HF with reduced EF iv) To assess the influence of age, gender, BMI, anaemia and renal failure on the ST2 and NT-proBNP levels. Design and Methods: A prospective double-blind study was conducted to obtain data from a sample of 64 cardiology patients. A blood sample was collected to test for ST2 and NT-proBNP. An echocardiogram (to obtain EF value), electrocardiogram and questionnaire were also obtained. Results: Of the 64 patients enrolled, 59.4% of the population had an EF less than 40%. At the end of the 30- day period, 7 patients were warded, 37 were not warded, one died and 17 were non respondent. Both biomarkers were efficacious at diagnosing HF with a reduced EF. However, neither of them were efficacious in predicting 30-day rehospitalization. The mean NT-proBNP values being: not rehospitalized (2114.7486) and 30 day rehospitalization (1008.42860) and the mean ST2 values being: not rehospitalized (336.1975), and 30-day rehospitalization. (281.9657). Conclusion: Neither ST2 or NT-proBNP was efficacious in predicting the short- term prognosis in HF with reduced EF. Both however were successful at confirming the diagnosis of HF in HF patients with reduced EF.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Esteban Balseiro ◽  
Cecilia Laspoumaderes ◽  
Facundo Smufer ◽  
Laura Wolinski ◽  
Beatriz Modenutti

AbstractIn this study, we analysed how short term temperature fluctuation interacts with nutrient limitation in the vertical migrating Daphnia commutata. We hypothesize that short term (daily) temperature fluctuation will alleviate nutrient limitation. We carried out experiments analysing growth rates, phosphorus and RNA content of D. commutate grown under four different temperature regimes and two P-limited conditions. Our experiments showed that individuals grown under fluctuating temperature grew more than at the mean temperature. We estimated the expected sizes for the 15 °C treatment based on the Q10 and for the fluctuating temperature treatment. These expected sizes for both treatments resulted well below the observed ones. The P and RNA content of individuals grown at 10 °C were significantly higher than those at 20 °C, and when individuals grown at 10 °C were translocated to 20 °C they exerted an increased growth rate. Our results suggest that, under a regime of diel vertical migration, the temperature alternation would allow migrating organisms to alleviate the effect of severe nutrient limitation maintaining population growth. Under a scenario of global warming, where epilimnetic temperatures will increase, lake temperature will interact with nutrient limitation for consumers, but, organisms may be able to face these changes if they can still regularly move from a cold hypolimnion to a warmer epilimnion.


2021 ◽  
Vol 13 (11) ◽  
pp. 5844
Author(s):  
Amy Roberts ◽  
Gregory S. Ching

The dialogue about study abroad is a contemporary trend. Since 2011, enrolments from the People’s Republic of China (PRC) have gradually increased and PRC students have now become one of the largest groups of incoming study abroad participants in Taiwan. In this study, investigators explored the characteristics of PRC students in comparison with other international students studying in Taiwan universities. Data were collected from 1870 study abroad students. Data collected include the various study abroad goals, prior study abroad experiences, the Short-term Study Abroad Situational Change Survey, the revised East Asian Acculturation Measures, the Study Abroad Acculturative Hassles, and their overall study abroad satisfaction. Data analyses included computation of the mean, frequency, cross-tabulation of respondents’ responses for identified questions, and various group comparisons. Implications suggest that the characteristics of PRC students are valuable and potentially transformative markers for sustainable cross-strait ties. Study abroad programs in Taiwan are noted as one piece of the emerging discourse for sustainable co-existence between Taiwan and the PRC. As such, PRC study abroad participants along with faculty and students in Taiwan universities have an opportunity to play a role in reshaping future exchanges as well as transforming themselves into stewards of a trans-Pacific community.


1984 ◽  
Vol 32 (5) ◽  
pp. 495 ◽  
Author(s):  
BA Myers ◽  
TF Neales

Field observations of some parameters of the water relations of the two eucalypt species E. behriana and E. microcarpa in dry sclerophyll, mallee and woodland vegetation were made at three sites from 1980 to 1983. The mean ( n = 519) water potential measured at dawn (Ψdawn) was -3.07± 0.01 MPa and fluctuated seasonally with rainfall intensity over the range -2.0 ± 0, 1 to -4.4 ± 0.1 MPa ( n = 30). Both species behaved similarly and some osmotic adjustment took place. Mean leaf conductance (gs) varied between 0.151 ± 0.006 and 0.003 ± 0.001 mol m-2 s-1 . Maximum daily values of gs were linearly related to Ψdawn as it fluctuated seasonally. The slope of this linear regression was not significantly different from that relating these values of gs and Ψ, when both were measured concurrently. There were thus no indications of a distinction between the responses of gs to long- and short-term fluctuations of Ψ or of a threshold-type response of gs to Ψ. Field measurements indicated that gs was decreased at high values of vapour pressure difference (Δe). In laboratory studies with seedlings of the two species gs decreased from 0.5 to 0.1 mol m-2 s-I as Δe increased from 0.5 to 3.0 kPa. Leaf and canopy conductance were the predominant plant determinants of transpiration rate (Er) in this type of vegetation which has the capacity to restrict Et via the effect of water potential (Ψ) on gs and also by the response of gs to Δe. Some of the water relations parameters of E. behriana indicated that this species was better able to withstand drought than was E microcarpa.


2001 ◽  
Vol 92 (1) ◽  
pp. 234-250 ◽  
Author(s):  
Kenichi Kaneko ◽  
Kazuyoshi Sakamoto

Visual fatigue caused by prolonged work viewing a Visual Display Terminals (VDT) and of work reading a hard-copy were assessed by electromyogram (EMG) waveform and electrooculogram (EOG) waveform in spontaneous blinks as objective criteria, and by questionnaire of subjective feeling, and by task performance. The duration and the amplitude of the EMG of the orbicularis ocular muscle on the right side and the EOG of the vertical direction to the eyelid were measured for 10 subjects who participated in a figure task consisting of the addition of single-digit numbers on a VDT work or a work with a hard-copy. The mean values of the duration and the amplitude of the EMG and the EOG were evaluated by the averaging of 10 waveforms of the spontaneous blinks for all subjects. The time lag from the EMG to the EOG in the process of the generation of spontaneous blinks was also analyzed. These five parameters were evaluated during the work time. The mean values for the duration of the EMG increased gradually during the work time, but the amplitude did not show significant difference between the prework and a work time. There was no significant change of the duration of the EOG, but the mean amplitude of the EOG decreased as the work time progressed, and the time lag significantly extended. The blinks frequency increased relatively when using a VDT. The rate of fluctuation for these parameters was higher during use of a VDT than use of a hard-copy. The time lag at five hours of VDT work was extended by 90% based on the value at the prework. The symptoms of general fatigue and fatigue of the eyes increased linearly during the VDT work for six hours. The results indicated a significant correlation between the objective parameters for the activity of the spontaneous blinks, i.e., duration and amplitude of EMG and EOG, and the time lag between EMG and EOG, and the subjective feeling was recognized in the time course of the task. These experimental results suggested that the parameters regarding the EMG and the EOG for the spontaneous blinks were effective indices for assessing visual fatigue during prolonged VDT work.


1988 ◽  
Vol 22 (3) ◽  
pp. 202-204 ◽  
Author(s):  
Merlin V. Nelson ◽  
Vickie Tutag-Lehr ◽  
R. Lee Evans

Nine normal, healthy male subjects had significantly elevated thyroid-stimulating hormone (TSH) concentrations while receiving oral lithium carbonate for two weeks. The mean minimum lithium serum concentration was 0.765 mEq/L. The TSH concentrations after 15 days on lithium were significantly correlated to the TSH concentration at baseline. No correlation was found between mean minimum lithium steady-state concentration and TSH concentration after 15 days on lithium. Further research is necessary to determine if a high baseline TSH concentration or an early rise in TSH will predict those patients who will eventually develop hypothyroidism after long-term lithium therapy.


2009 ◽  
Vol 24 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Jan Krul ◽  
Armand R. J. Girbes

AbstractObjective:The objective of this study was to report on a nine years of experience of providing medical support during house parties (raves) in the Netherlands, where they can be organized legally.Design:This was a prospective, observational study of self-referred patients from 1997 to 2005. During raves, first aid stations are staffed with specifically trained medical and paramedical personnel. Self-referred patients were diagnosed, treated, and recorded using standardized methods.Results:During a nine-year period with 219 raves occurred, involving approximately three million participants, 23,581 patients visited the first aid stations. The medical usage rate (MUR) varied from 59–170 patients per 10,000 rave participants. The mean age increased from 1997 to 2005 from 18.7 ±2.7 to 23.3 ±5.7 years. The mean stay at the first aid station was 18 ±46 minutes. Most health problems were mild. Fifteen cases of severe incidents were observed with one death.Conclusions:Unique data from the Netherlands demonstrate a low number of serious, health-related, short-term problems during raves.


2012 ◽  
Vol 12 (5) ◽  
pp. 1789-1797 ◽  
Author(s):  
R. Gómez-Beas ◽  
A. Moñino ◽  
M. J. Polo

Abstract. In compliance with the development of the Water Framework Directive, there is a need for an integrated management of water resources, which involves the elaboration of reservoir management models. These models should include the operational and technical aspects which allow us to forecast an optimal management in the short term, besides the factors that may affect the volume of water stored in the medium and long term. The climate fluctuations of the water cycle that affect the reservoir watershed should be considered, as well as the social and economic aspects of the area. This paper shows the development of a management model for Rules reservoir (southern Spain), through which the water supply is regulated based on set criteria, in a sustainable way with existing commitments downstream, with the supply capacity being well established depending on demand, and the probability of failure when the operating requirements are not fulfilled. The results obtained allowed us: to find out the reservoir response at different time scales, to introduce an uncertainty analysis and to demonstrate the potential of the methodology proposed here as a tool for decision making.


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