scholarly journals Elasmobranch Responses to Experimental Warming, Acidification, and Oxygen Loss—A Meta-Analysis

2021 ◽  
Vol 8 ◽  
Author(s):  
Catarina Pereira Santos ◽  
Eduardo Sampaio ◽  
Beatriz P. Pereira ◽  
Maria Rita Pegado ◽  
Francisco O. Borges ◽  
...  

Despite the long evolutionary history of this group, the challenges brought by the Anthropocene have been inflicting an extensive pressure over sharks and their relatives. Overexploitation has been driving a worldwide decline in elasmobranch populations, and rapid environmental change, triggered by anthropogenic activities, may further test this group's resilience. In this context, we searched the literature for peer-reviewed studies featuring a sustained (>24 h) and controlled exposure of elasmobranch species to warming, acidification, and/or deoxygenation: three of the most pressing symptoms of change in the ocean. In a standardized comparative framework, we conducted an array of mixed-model meta-analyses (based on 368 control-treatment contrasts from 53 studies) to evaluate the effects of these factors and their combination as experimental treatments. We further compared these effects across different attributes (lineages, climates, lifestyles, reproductive modes, and life stages) and assessed the direction of impact over a comprehensive set of biological responses (survival, development, growth, aerobic metabolism, anaerobic metabolism, oxygen transport, feeding, behavior, acid-base status, thermal tolerance, hypoxia tolerance, and cell stress). Based on the present findings, warming appears as the most influential factor, with clear directional effects, namely decreasing development time and increasing aerobic metabolism, feeding, and thermal tolerance. While warming influence was pervasive across attributes, acidification effects appear to be more context-specific, with no perceivable directional trends across biological responses apart from the necessary to achieve acid-base balance. Meanwhile, despite its potential for steep impacts, deoxygenation has been the most neglected factor, with data paucity ultimately precluding sound conclusions. Likewise, the implementation of multi-factor treatments has been mostly restricted to the combination of warming and acidification, with effects approximately matching those of warming. Despite considerable progress over recent years, research regarding the impact of these drivers on elasmobranchs lags behind other taxa, with more research required to disentangle many of the observed effects. Given the current levels of extinction risk and the quick pace of global change, it is further crucial that we integrate the knowledge accumulated through different scientific approaches into a holistic perspective to better understand how this group may fare in a changing ocean.

Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 63
Author(s):  
Mohammed A. Dakhil ◽  
Marwa Waseem A. Halmy ◽  
Walaa A. Hassan ◽  
Ali El-Keblawy ◽  
Kaiwen Pan ◽  
...  

Climate change is an important driver of biodiversity loss and extinction of endemic montane species. In China, three endemic Juniperus spp. (Juniperuspingii var. pingii, J.tibetica, and J.komarovii) are threatened and subjected to the risk of extinction. This study aimed to predict the potential distribution of these three Juniperus species under climate change and dispersal scenarios, to identify critical drivers explaining their potential distributions, to assess the extinction risk by estimating the loss percentage in their area of occupancy (AOO), and to identify priority areas for their conservation in China. We used ensemble modeling to evaluate the impact of climate change and project AOO. Our results revealed that the projected AOOs followed a similar trend in the three Juniperus species, which predicted an entire loss of their suitable habitats under both climate and dispersal scenarios. Temperature annual range and isothermality were the most critical key variables explaining the potential distribution of these three Juniperus species; they contribute by 16–56.1% and 20.4–38.3%, respectively. Accounting for the use of different thresholds provides a balanced approach for species distribution models’ applications in conservation assessment when the goal is to assess potential climatic suitability in new geographical areas. Therefore, south Sichuan and north Yunnan could be considered important priority conservation areas for in situ conservation and search for unknown populations of these three Juniperus species.


2021 ◽  
pp. 019459982199474
Author(s):  
Maggie Xing ◽  
Dorina Kallogjeri ◽  
Jay F. Piccirillo

Objective To evaluate the effectiveness of cognitive training in improving tinnitus bother and to identify predictors of patient response. Study Design Prospective open-label randomized controlled trial. Setting Online. Methods Participants were adults with subjective idiopathic nonpulsatile tinnitus causing significant tinnitus-related distress. The intervention group trained by using auditory-intensive exercises for 20 minutes per day, 5 days per week, for 8 weeks. The active control group trained on the same schedule with non–auditory intensive games. Surveys were completed at baseline, 8 weeks, and 12 weeks. Results A total of 64 participants completed the study. The median age was 63 years (range, 25-69) in the intervention group and 61 years (34-68) in the control group. Mixed model analysis revealed that within-subject change in Tinnitus Functional Index in the intervention group was not different than the control group, with marginal mean differences (95% CI): 0.24 (–11.20 to 10.7) and 2.17 (–8.50 to 12.83) at 8 weeks and 2.33 (–8.6 to 13.3) and 3.36 (–7.91 to 14.6) at 12 weeks, respectively. When the 2 study groups were compared, the control group had higher Tinnitus Functional Index scores than the intervention group by 10.5 points at baseline (95% CI, –0.92 to 29.89), 8.1 at 8 weeks (95% CI, –3.27 to 19.42), and 9.4 at 12 weeks (95% CI, –2.45 to 21.34). Conclusion Auditory-intensive cognitive training was not associated with changes in self-reported tinnitus bother. Given the potential for neuroplasticity to affect tinnitus, we believe that future studies on cognitive training for tinnitus remain relevant.


Author(s):  
Judith Rösler ◽  
Stefan Georgiev ◽  
Anna L. Roethe ◽  
Denny Chakkalakal ◽  
Güliz Acker ◽  
...  

AbstractExoscopic surgery promises alleviation of physical strain, improved intraoperative visualization and facilitation of the clinical workflow. In this prospective observational study, we investigate the clinical usability of a novel 3D4K-exoscope in routine neurosurgical interventions. Questionnaires on the use of the exoscope were carried out. Exemplary cases were additionally video-documented. All participating neurosurgeons (n = 10) received initial device training. Changing to a conventional microscope was possible at all times. A linear mixed model was used to analyse the impact of time on the switchover rate. For further analysis, we dichotomized the surgeons in a frequent (n = 1) and an infrequent (n = 9) user group. A one-sample Wilcoxon signed rank test was used to evaluate, if the number of surgeries differed between the two groups. Thirty-nine operations were included. No intraoperative complications occurred. In 69.2% of the procedures, the surgeon switched to the conventional microscope. While during the first half of the study the conversion rate was 90%, it decreased to 52.6% in the second half (p = 0.003). The number of interventions between the frequent and the infrequent user group differed significantly (p = 0.007). Main reasons for switching to ocular-based surgery were impaired hand–eye coordination and poor depth perception. The exoscope investigated in this study can be easily integrated in established neurosurgical workflows. Surgical ergonomics improved compared to standard microsurgical setups. Excellent image quality and precise control of the camera added to overall user satisfaction. For experienced surgeons, the incentive to switch from ocular-based to exoscopic surgery greatly varies.


Horticulturae ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 140
Author(s):  
Avela Sogoni ◽  
Muhali Jimoh ◽  
Learnmore Kambizi ◽  
Charles Laubscher

Climate change, expanding soil salinization, and the developing shortages of freshwater have negatively affected crop production around the world. Seawater and salinized lands represent potentially cultivable areas for edible salt-tolerant plants. In the present study, the effect of salinity stress on plant growth, mineral composition (macro-and micro-nutrients), and antioxidant activity in dune spinach (Tetragonia decumbens) were evaluated. The treatments consisted of three salt concentrations, 50, 100, and 200 mM, produced by adding NaCl to the nutrient solution. The control treatment had no NaCl but was sustained and irrigated by the nutrient solution. Results revealed a significant increase in total yield, branch production, and ferric reducing antioxidant power in plants irrigated with nutrient solution incorporated with 50 mM NaCl. Conversely, an increased level of salinity (200 mM) caused a decrease in chlorophyll content (SPAD), while the phenolic content, as well as nitrogen, phosphorus, and sodium, increased. The results of this study indicate that there is potential for brackish water cultivation of dune spinach for consumption, especially in provinces experiencing the adverse effect of drought and salinity, where seawater or underground saline water could be diluted and used as irrigation water in the production of this vegetable.


Author(s):  
Amy L Petry ◽  
Nichole F Huntley ◽  
Michael R Bedford ◽  
John F Patience

Abstract In theory, supplementing xylanase in corn-based swine diets should improve nutrient and energy digestibility and fiber fermentability, but its efficacy is inconsistent. The experimental objective was to investigate the impact of xylanase on energy and nutrient digestibility, digesta viscosity, and fermentation when pigs are fed a diet high in insoluble fiber (>20% neutral detergent fiber; NDF) and given a 46-d dietary adaptation period. Three replicates of 20 growing gilts were blocked by initial body weight, individually housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF) with 7.5% NDF, a 30% corn bran high-fiber control (HF; 21.9% NDF), HF+100 mg xylanase/kg [HF+XY, (Econase XT 25P; AB Vista, Marlborough, UK)] providing 16,000 birch xylan units/kg; and HF+50 mg arabinoxylan-oligosaccharide (AXOS) product/kg [HF+AX, (XOS 35A; Shandong Longlive Biotechnology, Shandong, China)] providing AXOS with 3-7 degrees of polymerization. Gilts were allowed ad libitum access to fed for 36-d. On d 36, pigs were housed in metabolism crates for a 10-d period, limit fed, and feces were collected. On d 46, pigs were euthanized and ileal, cecal, and colonic digesta were collected. Data were analyzed as a linear mixed model with block and replication as random effects, and treatment as a fixed effect. Compared with LF, HF reduced the apparent ileal digestibility (AID), apparent cecal digestibility (ACED), apparent colonic digestibility (ACOD), and apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), crude protein (CP), acid detergent fiber (ADF), NDF, and hemicellulose (P<0.01). Relative to HF, HF+XY improved the AID of GE, CP, and NDF (P<0.05), and improved the ACED, ACOD, and ATTD of DM, GE, CP, NDF, ADF, and hemicellulose (P<0.05). Among treatments, pigs fed HF had increased hindgut DM disappearance (P=0.031). Relative to HF, HF+XY improved cecal disappearance of DM (162 vs. 98g; P=0.008) and NDF (44 vs. 13g; P<0.01). Pigs fed xylanase had a greater proportion of acetate in cecal digesta and butyrate in colonic digesta among treatments (P<0.05). Compared with LF, HF increased ileal, cecal, and colonic viscosity, but HF+XY decreased ileal viscosity compared with HF (P<0.001). In conclusion, increased insoluble corn-based fiber decreases digestibility, reduces cecal fermentation, and increases digesta viscosity, but supplementing xylanase partially mitigated that effect.


Author(s):  
Natalie Rose ◽  
Les Dolega

AbstractThe weather is considered as an influential factor on consumer purchasing behaviours and plays a significant role in many aspects of retail sector decision making. As a result, better understanding of the magnitude and nature of the influence of variable UK weather conditions can be beneficial to many retailers and other stakeholders. This study addresses the dearth of research in this area by quantifying the relationship between different weather conditions and trading outcomes. By employing comprehensive daily sales data for a major high street retailer with over 2000 stores across England and adopting a random forest methodology, the study quantifies the influence of various weather conditions on daily retail sales. Results indicate that weather impact is greatest in the summer and spring months and that wind is consistently found to be the most influential weather condition. The top five most weather-dependent categories cover a range of different product types, with health foods emerging as the most susceptible to the weather. Also, sales from out-of-town stores show a far more complex relationship with the weather than those from traditional high street stores with the regions London and the South East experiencing the greatest levels of influence. Various implications of these findings for retail stakeholders are discussed and the scope for further research outlined.


Author(s):  
Surinder Kaur M. S. Pada ◽  
Poh Lishi ◽  
Kim Sim Ng ◽  
Sarathamani Rethenam ◽  
Lilibeth Silagan Alenton ◽  
...  

Abstract Background Computerisation of various processes in hospitals and reliance on electronic devices raises the concern of contamination of these devices from the patient environment. We undertook this study to determine if an attached hand hygiene device that unlocks the screen of a computer on wheels (COW) on usage can be effective in decreasing the microbiological burden on computer keyboards. Methods An electronic hand sanitizer was integrated onto the COW. A prospective cohort study with a crossover design involving 2 control and 2 intervention wards was used. The study end point was the number of colony forming units found on the keyboards. Bacteria were classified into 4 main groups; pathogenic, skin flora, from the environment or those thought to be commensals in healthy individuals. We then used a mixed effects model for the statistical analysis to determine if there were any differences before and after the intervention. Results Thirty-nine keyboards were swabbed at baseline, day 7 and 14, with 234 keyboards cultured, colony forming units (CFUs) counted and organisms isolated. By mixed model analysis, the difference of mean bacteria count between intervention and control for week 1 was 32.74 (− 32.74, CI − 94.29 to 28.75, p = 0.29), for week 2 by 155.86 (− 155.86, CI − 227.45 to − 83.53, p < 0.0001), and after the 2-week period by 157.04 (− 157.04, CI − 231.53 to − 82.67, p < 0.0001). In the sub-analysis, there were significant differences of pathogenic bacteria counts for the Intervention as compared to the Control in contrast with commensal counts. Conclusion A hand hygiene device attached to a COW may be effective in decreasing the microbiological burden on computer keyboards.


2020 ◽  
Vol 13 (1) ◽  
pp. 219-245
Author(s):  
Rosa Vallejos ◽  
Evelyn Fernández-Lizárraga ◽  
Haley Patterson

AbstractThis study analyzes the instantiation of objects in Peruvian Amazonian Spanish (PAS) discourse in two communities with distinct linguistic contexts. We examine the impact of two social variables (gender and place) and nine linguistic variables (transitivity, animacy, definiteness, anaphora function, anaphora expression, cataphora function, cataphora expression, activation, topic persistence) on the speech of eight participants. Our findings indicate that null instantiation in PAS is pervasive, occurring with a range of verb lexemes. While neither gender nor place are significant predictors of null objects, various linguistic variables contribute to the instantiation of objects. The five significant variables as determined by a mixed model regression analysis include the following: animacy, definiteness, anaphora expression, cataphora expression, and activation status. Several findings are consistent with previous research (e. g. human and definite referents disfavor null objects), while other results differ (e. g. PAS propositions disfavor null objects). Activation status and anaphora expression are the most significant predictors of null objects in PAS. In particular, highly accessible referents in discourse and anaphoric null objects favored null objects in subsequent clauses. Thus, the results in the present study demonstrate the pivotal role of information structure in object instantiation, furthering the discussion on syntax-discourse interplay phenomena.


2012 ◽  
Vol 532-533 ◽  
pp. 1445-1449
Author(s):  
Ting Ting Tong ◽  
Zhen Hua Wu

EM algorithm is a common method to solve mixed model parameters in statistical classification of remote sensing image. The EM algorithm based on fuzzification is presented in this paper to use a fuzzy set to represent each training sample. Via the weighted degree of membership, different samples will be of different effect during iteration to decrease the impact of noise on parameter learning and to increase the convergence rate of algorithm. The function and accuracy of classification of image data can be completed preferably.


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