Toxicity and bioaccumulation of fluoride ion on Branchiura sowerbyi, Beddard, (Oligochaeta, Tubificidae)

Fluoride concentrations are increasing significantly in many aquatic ecosystems as a consequence of human activities (agrochemicals, pharmaceuticals, refrigerants, pesticides, surfactant compounds). Several investigations have revealed that sensitivity to fluorides and safe concentrations vary greatly within classes, families and genera. Aquatic oligochaetes have often been used for pollution assessment and accumulation testing, but no information has been given about tolerance to fluoride ion. Among endobenthic tubificids Branchiura sowerbyi is easily identifiable (evident posterior gills, large size) and particularly useful for tissue requirements in chemical analysis. The purpose of this study was to examine the tolerance of this tubificid to fluoride ion and its bioaccumulation capacity by performing short (LC50 96h) and long-term (18 day) experiments at different temperatures (17°C and 22 °C). LC50 values (91.3 and 61.7 mg/L for 17°C and 22°C respectively), especially in the presence of sediment (267.6 and 80.1 mg/L for 17°C and 22°C respectively) showed that B. sowerbyi is more resistant to fluoride than other freshwater invertebrates. Fluoride became more toxic with increased temperature, demonstrating that seasonal temperature changes could influence the sensitivity of this freshwater tubificid. Bioaccumulation was lower when the organisms were exposed to sodium fluoride in the absence of sediment, indicating that this animal also accumulates fluoride by ingesting sediment.

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Germination requirements of Oenothera biennis seeds during burial under natural seasonal temperature cycles

Canadian Journal of Botany ◽

10.1139/b94-098 ◽

1994 ◽

Vol 72 (6) ◽

pp. 779-782 ◽

Cited By ~ 26

Author(s):

Carol C. Baskin ◽

Jerry M. Baskin

Keyword(s):

Seed Banks ◽

Late Winter ◽

Seasonal Temperature ◽

Oenothera Biennis ◽

Light Requirement ◽

Term Survival ◽

Temperature Changes ◽

Buried Seeds ◽

Dormancy Cycles

Buried seeds of Oenothera biennis, which have the potential to form long-lived seed banks, were investigated to determine whether or not they (i) undergo seasonal changes in their dormancy states and (ii) require light for germination. Seeds were buried in soil and exposed to natural seasonal temperature changes. Samples of seeds were exhumed at monthly intervals for 31 months and tested for germination in light and darkness at 12-h daily thermoperiods of 15:6, 20:10, 25:15, 30:15, and 35:20 °C. At maturity in autumn, seeds germinated to 84–95% in light at 30:15 and 35:20 °C, but to 0–69% at other test conditions. By late winter, seeds germinated to 95–100% at the five thermoperiods in light and in darkness. In summer and autumn, germination in light decreased at 15:6 °C, and in darkness it dropped to 0% at 15:6 °C and decreased at 20:10, 25:15, 30:15, and 35:20 °C. Following the second winter of burial, seeds germinated to near 100% at all thermoperiods in light and darkness. Thus, seeds exhibited an annual nondormancy – conditional dormancy cycle, being nondormant from midwinter to late spring and conditionally dormant in summer and autumn. Oenothera biennis is 1 of 10 species whose seeds live for 39–40 years or longer in soil and also have an annual conditional dormancy – nondormancy cycle. Seeds of six of these species, including O. biennis, can germinate in darkness in spring or summer at simulated habitat temperatures. Therefore, a light requirement for germination is not necessarily a prerequisite for long-term survival of buried seeds, and something other than darkness prevents germination of seeds of some species buried in soil. Key words: seed banks, buried seeds, germination, dormancy cycles, light requirement, Oenothera.

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Climate Change, Temperature, and Homicide: A Tale of Two Cities, 1895–2015

Weather Climate and Society ◽

10.1175/wcas-d-19-0068.1 ◽

2020 ◽

Vol 12 (1) ◽

pp. 171-181 ◽

Cited By ~ 1

Author(s):

Michael J. Lynch ◽

Paul B. Stretesky ◽

Michael A. Long

Keyword(s):

Climate Change ◽

New York ◽

Seasonal Temperature ◽

Temperature Changes ◽

Temperature Trends ◽

Two Cities ◽

Change Temperature ◽

The Relationship ◽

Seasonal Weather

AbstractIt has been argued that the temperature increase caused by anthropogenic climate change will produce a significant increase in violent crime. Support for that prediction is often based on statistical analyses of seasonal temperature and crime data cycles across days, months, and quarters and sometimes on large geographic areas. Within-year temperature changes are very large, however, relative to the 30-yr temperature increases employed to measure climate change. In addition, because temperature trends associated with climate change vary geographically, analyses should employ small geographic units for which temperature changes are measured over yearly intervals and for long periods of time. To address these conditions, this study examined the long-term temperature–crime association for homicides in New York and London for 1895–2015. Consistent with previous studies examining seasonal weather and crime patterns, we found a positive correlation between annual homicide rates and temperature, but only at the bivariate level. This relationship became statistically insignificant in both New York and London when gross domestic product is controlled. Moreover, the bivariate relationship between temperature and homicide is statistically insignificant when correcting for nonstationarity. Thus, it does not appear that climate change has led to higher rates of homicide in New York and London over the long term. These nonfindings are important because they suggest that studies of climate change and violence might do well to consider alternative mechanisms that mediate the relationship between climate change and violence.

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Comparative Labelling and Biokinetic Studies of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn)

Nuklearmedizin ◽

10.1055/s-0037-1620603 ◽

1977 ◽

Vol 16 (01) ◽

pp. 30-35 ◽

Cited By ~ 1

Author(s):

N. Agha ◽

R. B. R. Persson

Keyword(s):

Complex Formation ◽

Significant Influence ◽

Room Temperature ◽

Ph Value ◽

Maximum Activity ◽

Reduction Step ◽

Labelling Yield ◽

Different Temperatures ◽

Kinetics Of

SummaryGelchromatography column scanning has been used to study the fractions of 99mTc-pertechnetate, 99mTcchelate and reduced hydrolyzed 99mTc in preparations of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn). The labelling yield of 99mTc-EDTA(Sn) chelate was as high as 90—95% when 100 μmol EDTA · H4 and 0.5 (Amol SnCl2 was incubated with 10 ml 99mTceluate for 30—60 min at room temperature. The study of the influence of the pH-value on the fraction of 99mTc-EDTA shows that pH 2.8—2.9 gave the best labelling yield. In a comparative study of the labelling kinetics of 99mTc-EDTA(Sn) and 99mTc- DTPA(Sn) at different temperatures (7, 22 and 37°C), no significant influence on the reduction step was found. The rate constant for complex formation, however, increased more rapidly with increased temperature for 99mTc-DTPA(Sn). At room temperature only a few minutes was required to achieve a high labelling yield with 99mTc-DTPA(Sn) whereas about 60 min was required for 99mTc-EDTA(Sn). Comparative biokinetic studies in rabbits showed that the maximum activity in kidneys is achieved after 12 min with 99mTc-EDTA(Sn) but already after 6 min with 99mTc-DTPA(Sn). The long-term disappearance of 99mTc-DTPA(Sn) from the kidneys is about five times faster than that for 99mTc-EDTA(Sn).

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Heat wave effects on biomass and vegetative growth of macrophytes after long-term adaptation to different temperatures: a mesocosm study

Climate Research ◽

10.3354/cr01352 ◽

2015 ◽

Vol 66 (3) ◽

pp. 265-274 ◽

Cited By ~ 16

Author(s):

Y Cao ◽

ÉM Neif ◽

W Li ◽

J Coppens ◽

N Filiz ◽

...

Keyword(s):

Heat Wave ◽

Vegetative Growth ◽

Wave Effects ◽

Different Temperatures

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Modern Possibilities of Organ-Preserving Treatment in Children with Intraocular Retinoblastoma

Oncopediatrics ◽

10.15690/onco.v5i3.1935 ◽

2018 ◽

Vol 5 (3) ◽

pp. 175-187 ◽

Cited By ~ 1

Author(s):

O. V. Gorovtsova ◽

T. L. Ushakova ◽

V. G. Polyakov

Keyword(s):

Drug Delivery ◽

Survival Rate ◽

Cancer Therapy ◽

Neoadjuvant Chemotherapy ◽

Patient Survival ◽

Focal Therapy ◽

Local Drug Delivery ◽

Large Size ◽

Intraocular Retinoblastoma

Retinoblastoma is one of highly curable diseases; today the total 5-year survival rate in patients with retinoblastoma exceeds 95%. The article summarizes the current world experience on treatment of patients with intraocular retinoblastoma. The treating skills of intraocular malignant tumor in children are a balance between the patient’s life and the preservation of an eye and its visual functions. The complex and challenging task is the treatment of common intraocular retinoblastoma groups «C», «D», «E» when the large size or localization of the tumor does not allow performing the local (focal) destruction of the tumor. As a rule, in such cases neoadjuvant chemotherapy (CT) is performed at the first stage in order to reduce the size of the tumor for further focal therapy. However, the analysed data on the effectiveness of neoadjuvant CT in combination with focal or radiotherapy demonstrated the limited possibilities of the proposed therapy. Local drug delivery in cancer therapy became a real breakthrough in the organ-preserving treatment of children with large intraocular retinoblastoma. The most widely used current methods of local drug delivery are intravitreal (IVitC) and selective intra-arterial chemotherapy (SIAC) as monotherapy or in combination with neoadjuvant CT and focal therapy which significantly increased the percentage of preserved eyes without radiotherapy administration or damage to the patient survival. The review discusses the different IVitC and SIAC techniques, chemotherapy schemes, dosages of chemotherapy, immediate and long-term complications of treatment.

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Rolling Resistance Calculation Procedure Using the Finite Element Method

Tire Science and Technology ◽

10.2346/tire.19.170158 ◽

2019 ◽

Vol 48 (3) ◽

pp. 224-248

Author(s):

Pablo N. Zitelli ◽

Gabriel N. Curtosi ◽

Jorge Kuster

Keyword(s):

Finite Element ◽

Energy Dissipation ◽

Rolling Resistance ◽

Element Model ◽

The Finite Element Method ◽

Temperature Changes ◽

Rubber Compounds ◽

Different Temperatures ◽

Materials Used ◽

Account Temperature

ABSTRACT Tire engineers are interested in predicting rolling resistance using tools such as numerical simulation and tests. When a car is driven along, its tires are subjected to repeated deformation, leading to energy dissipation as heat. Each point of a loaded tire is deformed as the tire completes a revolution. Most energy dissipation comes from the cyclic loading of the tire, which causes the rolling resistance in addition to the friction force in the contact patch between the tire and road. Rolling resistance mainly depends on the dissipation of viscoelastic energy of the rubber materials used to manufacture the tires. To obtain a good rolling resistance, the calculation method of the tire finite element model must take into account temperature changes. It is mandatory to calibrate all of the rubber compounds of the tire at different temperatures and strain frequencies. Linear viscoelasticity is used to model the materials properties and is found to be a suitable approach to tackle energy dissipation due to hysteresis for rolling resistance calculation.

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Modeling of unforced demand response programs

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2020-0208 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Hassan Jalili ◽

Pierluigi Siano

Keyword(s):

Demand Response ◽

Load Shifting ◽

Response Models ◽

Temperature Changes ◽

Proposed Model ◽

Equipment Failures ◽

Demand Response Programs ◽

Simultaneous Implementation ◽

Long Term Studies

Abstract Demand response programs are useful options in reducing electricity price, congestion relief, load shifting, peak clipping, valley filling and resource adequacy from the system operator’s viewpoint. For this purpose, many models of these programs have been developed. However, the availability of these resources has not been properly modeled in demand response models making them not practical for long-term studies such as in the resource adequacy problem where considering the providers’ responding uncertainties is necessary for long-term studies. In this paper, a model considering providers’ unavailability for unforced demand response programs has been developed. Temperature changes, equipment failures, simultaneous implementation of demand side management resources, popular TV programs and family visits are the main reasons that may affect the availability of the demand response providers to fulfill their commitments. The effectiveness of the proposed model has been demonstrated by numerical simulation.

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Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽

10.3390/biology10060522 ◽

2021 ◽

Vol 10 (6) ◽

pp. 522

Author(s):

Régis Santos ◽

Wendell Medeiros-Leal ◽

Osman Crespo ◽

Ana Novoa-Pabon ◽

Mário Pinho

Keyword(s):

Population Structure ◽

Life History ◽

Deep Sea ◽

Management Strategies ◽

Size Composition ◽

Large Size ◽

The Common ◽

Fishing Impacts ◽

Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

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Glycemic Control Potential of Chemically Characterized Extract from Withania frutescens L. Roots in Severe Diabetes-Induced Mice

Applied Sciences ◽

10.3390/app11093998 ◽

2021 ◽

Vol 11 (9) ◽

pp. 3998

Author(s):

Abdelfattah El Moussaoui ◽

Hamza Mechchate ◽

Mohammed Bourhia ◽

Imane Es-safi ◽

Ahmad Mohammad Salamatullah ◽

...

Keyword(s):

Chemical Analysis ◽

Plant Extract ◽

Biochemical Parameters ◽

Pharmaceutical Drugs ◽

Glucose Lowering ◽

Natural Agents ◽

Severe Diabetes ◽

Treatment Of Diabetes ◽

Different Doses

Diabetes mellitus is a metabolic syndrome that causes impairment, mortality, and many other complications. Insulin and several synthetic medications are currently used in the treatment of diabetes. However, these pharmaceutical drugs are costly, and therefore medicines place priority on alternatives to fight this lethal disease. This modest study aims to investigate the chemical composition, antidiabetic and antihyperglycemic potentials along with subacute toxicity (bodyweight change and biochemical parameters) of hydroethanol extract from Withania frutescens L. roots (WFRE). The chemical analysis was carried out using GC–MS after extract silylation. The chemical analysis identified many potentially active compounds that may determine the antidiabetic results of WFRE. The antidiabetic effect of WFRE was evaluated in mice with severe diabetes using oral administration of doses up to 400 mg/kg for 28 days. The results of the antidiabetic and antihyperglycemic tests indicate that WFRE possesses promising glucose-lowering effects and, as a result, it may serve as an antidiabetic alternative for long-term use. The 4-week treatments with different doses of plant extract did not alter the bodyweight appearance of the diabetic mice nor their biochemical parameters (AST and ALT). The findings obtained indicate that the studied plant extract controlled severe diabetes in mice. Therefore, Withania frutescens L. can serve society as it provides natural agents to control diabetes.

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Impact of Prolonged Exposure of Eleven Years to Hot Seawater on the Degradation of a Thermoset Composite

Polymers ◽

10.3390/polym13132154 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2154

Author(s):

Amir Hussain Idrisi ◽

Abdel-Hamid I. Mourad ◽

Muhammad M. Sherif

Keyword(s):

Exposure Time ◽

Prolonged Exposure ◽

Mechanical Performance ◽

Matrix Cracking ◽

Pull Out ◽

Strength Based ◽

Different Temperatures ◽

River Line ◽

Composite Samples

This paper presents a long-term experimental investigation of E-glass/epoxy composites’ durability exposed to seawater at different temperatures. The thermoset composite samples were exposed to 23 °C, 45 °C and 65 °C seawater for a prolonged exposure time of 11 years. The mechanical performance as a function of exposure time was evaluated and a strength-based technique was used to assess the durability of the composites. The experimental results revealed that the tensile strength of E-glass/epoxy composite was reduced by 8.2%, 29.7%, and 54.4% after immersion in seawater for 11 years at 23 °C, 45 °C, and 65 °C, respectively. The prolonged immersion in seawater resulted in the plasticization and swelling in the composite. This accelerated the rate of debonding between the fibers and matrix. The failure analysis was conducted to investigate the failure mode of the samples. SEM micrographs illustrated a correlation between the fiber/matrix debonding, potholing, fiber pull-out, river line marks and matrix cracking with deterioration in the tensile characteristics of the thermoset composite.

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