scholarly journals Investigation of the Combined Effects of Rising Temperature and Pesticide Contamination on the Swimming Behaviour of Alpine Chironomids

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3618
Author(s):  
Valeria Lencioni ◽  
Valeria Di Nica ◽  
Sara Villa

Some pollutants can be transported through the atmosphere and travel medium–long distances to be deposited in glaciers at high altitude and latitude. The increase in the rate of glacier melting due to global warming can release these pollutants in alpine streams. This study investigated the combined effects of rising temperatures and chlorpyrifos (CPF) contamination on the swimming behaviour of alpine chironomids collected in a shrinking alpine glacier. We assessed the individual and interaction effects of rising temperatures (2–11 °C) and CPF concentrations (0–110 ng L−1) on the swimming behaviour of Diamesa zernyi (Chironomidae) larvae. Distance (mm) and speed (mm s−1) were recorded using a video-tracking system after 24–72 h of treatment. The two stressors caused different effects on distance and speed, with increasing temperature generally causing hyperactivity and CPF from hyperactivity to reduced mobility. Two interactions were detected between stressors when combined: (i) CPF superimposed the effect of temperature on both behavioural endpoints i.e., with 110 ng L−1 of CPF, at 11 °C, larvae moved less; (ii) warming (11 °C) magnified the negative effect of CPF: the smallest distance and slowest speed were recorded at the highest values of the two stressors after 72 h. Our results suggest that water contamination by CPF, even at sub-lethal concentrations, might increase the sensitivity of chironomids to warming, and vice versa, raising concerns about freshwater biodiversity conservation under climate change.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pi-Hsia Lee ◽  
Ting-Ting Yeh ◽  
Hsin-Yen Yen ◽  
Wan-Ling Hsu ◽  
Valeria Jia-Yi Chiu ◽  
...  

AbstractStroke and cognitive impairment are common in older population. They often occur together and their combined effects significantly increase disability in both basic (BADLs) and instrumental (IADLs) activities of daily living. We investigated the individual and combined impacts of stroke and cognitive impairment on BADLs and IADLs. A total of 3331 community-dwelling older adults were enrolled from the Taiwan longitudinal study on aging in 2011. Both BADLs and IADLs were analyzed. Combination of stroke and cognitive impairment increased severity of ADL disabilities, but similar prevalence, similar numbers of summed BADL and IADL tasks with disability, and similar levels of difficulty for each BADL and IADL task were found between the stroke group and cognitive impairment group. The former had more difficult in dressing while the latter had more difficult in using the telephone, transport, and managing finances. A hierarchy of ADLs was also observed in all groups. ADL skill training supplemented with cognitive and physical interventions should focus on secondary prevention of dementia and improve motor functional capacity to reduce loss of ADLs.


Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 771
Author(s):  
Toshiya Arakawa

Mammalian behavior is typically monitored by observation. However, direct observation requires a substantial amount of effort and time, if the number of mammals to be observed is sufficiently large or if the observation is conducted for a prolonged period. In this study, machine learning methods as hidden Markov models (HMMs), random forests, support vector machines (SVMs), and neural networks, were applied to detect and estimate whether a goat is in estrus based on the goat’s behavior; thus, the adequacy of the method was verified. Goat’s tracking data was obtained using a video tracking system and used to estimate whether they, which are in “estrus” or “non-estrus”, were in either states: “approaching the male”, or “standing near the male”. Totally, the PC of random forest seems to be the highest. However, The percentage concordance (PC) value besides the goats whose data were used for training data sets is relatively low. It is suggested that random forest tend to over-fit to training data. Besides random forest, the PC of HMMs and SVMs is high. However, considering the calculation time and HMM’s advantage in that it is a time series model, HMM is better method. The PC of neural network is totally low, however, if the more goat’s data were acquired, neural network would be an adequate method for estimation.


Author(s):  
James A. Koziol ◽  
Adriana Lucero ◽  
Jack C. Sipe ◽  
John S. Romine ◽  
Ernest Beutler

Objective:The Scripps neurologic rating scale (SNRS) is a summary measure of individual components comprising a neurological examination, designed for use in multiple sclerosis (MS). Our objective is to evaluate the responsiveness of the SNRS, within the context of a 2-year, randomized, double-blind crossover study of the efficacy of cladribine for treatment of secondary progressive MS.Methods:Effect sizes were determined for the SNRS and its components, separately for each treatment group (initial placebo, and initial cladribine) over both years of the clinical trial, using a standard random effects model.Results:Individual components tended to show positive effect sizes (improvement) during periods of active therapy in both treatment groups, and negative effect sizes (deterioration) during periods of no active therapy. Summation indices derived from the individual components of the SNRS seemed somewhat more stable than the individual components. The two components mentation and mood, and bladder, bowel, or sexual dysfunction, were rather unresponsive in our clinical trial.Conclusion:Changes in the components of the SNRS over the course of our clinical trial were consistent between the two treatment groups. Most components were moderately responsive; and, the summary SNRS score appropriately summarized the moderate magnitudes of change evinced in the individual components.


2005 ◽  
Vol 100 (1-3) ◽  
pp. 41-53 ◽  
Author(s):  
K FRANCOIS ◽  
F DEVLIEGHERE ◽  
K SMET ◽  
A STANDAERT ◽  
A GEERAERD ◽  
...  

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Oscar A. Mendoza Reales ◽  
Caterin Ocampo ◽  
Yhan Paul Arias Jaramillo ◽  
Juan Carlos Ochoa Botero ◽  
Jorge Hernán Quintero ◽  
...  

Decoupling the individual effects of multiwalled carbon nanotubes (MWCNTs) and surfactants when used as reinforcement materials in cement-based composites is aimed in this study. Powder MWCNTs were dispersed in deionized water using different types of surfactants as chemical dispersing agents and an ultrasonic tip processor. Cement pastes with carbon nanotubes additions of 0.15% by mass of cement were produced in two steps: first, the MWCNT/surfactant dispersions were combined with the mixing water, and then, cement was added and mixed until a homogeneous paste was obtained. Mechanical properties of the pastes cured at 7 days were measured, and their fracture behavior was characterized using the linear elastic finite element analysis. It was found that the reinforcing effect of MWCNT was masked by the negative effect of surfactants in the cement matrix; nevertheless, nanotubes were capable of increasing both stress and strain capacity of the composite by controlling the crack propagation process at the tip of the crack.


1989 ◽  
Vol 19 (4) ◽  
pp. 395-415 ◽  
Author(s):  
Jan H. Spyridakis

This study investigated the role of signaling in helping good readers comprehend expository text. As the existing literature on signaling, reviewed in the last issue of this Journal, pointed to deficiencies in previous studies' methodologies, one goal of this study was to refine prose research methods. Two passages were designed in one of eight signaled versions each. The design was constructed to assess the individual and combined effects of headings, previews, and logical connectives. The study also assessed the effect of passage length, familiarity, and difficulty. The results showed that signals do improve a reader's comprehension, particularly comprehension two weeks after the reading of a passage and comprehension of superordinate and superordinate inferential information. This study supports the hypothesis that signals can influence retention of text-based information, particularly with long, unfamiliar, or difficult passages.


2021 ◽  
Vol 22 (12) ◽  
pp. 6281
Author(s):  
Adrienn Balázs ◽  
Zelma Faisal ◽  
Rita Csepregi ◽  
Tamás Kőszegi ◽  
Balázs Kriszt ◽  
...  

Mycotoxins are toxic metabolites of filamentous fungi. Previous studies demonstrated the co-occurrence of Fusarium and Alternaria toxins, including zearalenone (ZEN), ZEN metabolites, and alternariol (AOH). These xenoestrogenic mycotoxins appear in soy-based meals and dietary supplements, resulting in the co-exposure to ZEN and AOH with the phytoestrogen genistein (GEN). In this study, the cytotoxic and estrogenic effects of ZEN, reduced ZEN metabolites, AOH, and GEN are examined to evaluate their individual and combined impacts. Our results demonstrate that reduced ZEN metabolites, AOH, and GEN can aggravate ZEN-induced toxicity; in addition, the compounds tested exerted mostly synergism or additive combined effects regarding cytotoxicity and/or estrogenicity. Therefore, these observations underline the importance and the considerable risk of mycotoxin co-exposure and the combined effects of mycoestrogens with phytoestrogens.


2013 ◽  
Vol 129 (1) ◽  
pp. 333-378 ◽  
Author(s):  
Henrik Jacobsen Kleven ◽  
Camille Landais ◽  
Emmanuel Saez ◽  
Esben Schultz

Abstract This article analyzes the effects of income taxation on the international migration and earnings of top earners using a Danish preferential foreigner tax scheme and population-wide Danish administrative data. This scheme, introduced in 1991, allows new immigrants with high earnings to be taxed at a preferential flat rate for a duration of three years. We obtain two main results. First, the scheme has doubled the number of highly paid foreigners in Denmark relative to slightly less paid—and therefore ineligible—foreigners. This translates into a very large elasticity of migration with respect to 1 minus the average tax rate on foreigners, between 1.5 and 2. Second, we find compelling evidence of a negative effect of the scheme-induced reduction in the average tax rate on pretax earnings of foreign migrants at the individual level. This finding can be rationalized by a matching frictions model with wage bargaining where there is a gap between pay and marginal productivity.


2020 ◽  
Vol 9 (5) ◽  
pp. 338
Author(s):  
Rexwhite T. Enakrire ◽  
Collence T. Chisita ◽  
Tella Adeyinka

Partnership is not a new phenomenon in the university environment. It embraces strategies used by people with common interest to harvest knowledge in terms of sharing or collaboration. However, the case differs with collaborations in Library and Information Science (LIS) research in Africa, especially LIS scholars in African universities in Nigeria and Zimbabwe. Paucity of empirical literature is available on research collaboration among LIS scholars in Nigerian and Zimbabwean universities. The purpose of the study was to examine partnership among librarians, with reflection on observation and interview research reports in three universities in Nigeria and Zimbabwe. The study adopted a qualitative approach using interview to gather data from librarians drawn from three Nigerian and Zimbabwean universities. The qualitative research approach grounded on content analysis of documents/literature, observation and interview method was use for the study. The observation focus on the authors’ exposition in the sampled universities environment, while the interview were key informants from each of the three countries universities sampled. The study consider the collaborative theory through grounded method. The findings of the study revealed lack of trust in the individual or groups collaborator; team members have the feeling that the project they are collaborating on is of little benefit, due to poor relationship. Team members see themselves as contender or challenger; which has affected leadership issue and involvement of long meetings and inability to address the truth. In terms of the influence of collaboration on professional growth of librarians, result demonstrated enhancement of teaching aspect of librarianship, learning and research quality; promote cooperation, coordination, which in turn increased level of intensity, tenacity and interaction among members. Linkage among LIS professional ranges from networking, cooperation, alliances, coordination and partnership, coalition and eventually collaboration. Challenges reported include catastrophic consequent on negative effect of work, culture and stylistic parameters including concept, attitude and professional hindrances. dominance impact of policies and procedures of collaboration, exploitation of the weak members, lack of clarity and rationale behind the collaboration, unwillingness to change by members in collaboration, lack of socialisation, largeness of the group, wrong membership and jettisoning of members ideas which eventually make some members take the decision of quitting the team. The study recommends inter-disciplinary, intra-institutional and inter-institutional collaboration among various stakeholders in LIS education and training.


2018 ◽  
Author(s):  
Mariano Calvo Martín ◽  
Stamatios C. Nicolis ◽  
Isaac Planas-Sitjà ◽  
Jean-Christophe de Biseau ◽  
Jean-Louis Deneubourg

AbstractCockroaches, like most social arthropods, are led to choose collectively among different alternative resting places. These decisions are modulated by different factors, such as environmental conditions (temperature, relative humidity) and sociality (groups size, nature of communications). The aim of this study is to establish the interplay between environmental conditions and the modulation of the interactions between individuals within a group leading to an inversion of preferences. We show that the preferences of isolated cockroaches and groups of 16 individuals, on the selection of the relative humidity of a shelter are inversed and shed light on the mechanisms involved. We suggest that the relative humidity has a multi-level influence on cockroaches, manifested as an attractant effect at the individual level and as a negative effect at the group level, modulating the interactions.


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