A new structural two-component epoxy adhesive: Strength and fracture characterization

30th International Conference on Flexible Automation and Intelligent Manufacturing (FAIM2021) -15-18 June 2021, Athens, GreeceIn the past decades, adhesive technology has been useful in order to solve numerous issues related with conventional joining techniques (bolting, riveting and welding). Several advantages of adhesive bonding can be pointed out, such as low weight (relevant in the automotive and aeronautical industries), capability to resist to adverse environmental conditions, lower manufacturing costs and possibility to join different materials. To predict crack propagation of an adhesive joint by advanced fracture mechanics-based techniques such as cohesive zone models (CZM) it is not enough to know the traditional mechanical properties, such as Young’s modulus (E), shear modulus (G), tensile strength (σf) and shear strength (τf). Actually, it is also mandatory to estimate the tensile (GIC) and shear fracture energies (GIIC). The purpose of this work is to carry out the mechanical and fracture property characterization of a new structural two-component epoxy adhesive. With this purpose, four tests which were conducted: tensile testing to bulk specimens, shear testing with thick adherend shear tests (TAST), double-cantilever beam (DCB) and end-notched flexure (ENF). With these tests, it was possible to determine the mechanical and fracture properties of the adhesive in tension and shear. Different data reduction methods were evaluated for the fracture properties. The test results agreed with the data provided by the manufacturer and will enable the design of bonded structures with this adhesive.The authors would like to thank Sika® Portugal for supplying the adhesive SikaPower® 1277info:eu-repo/semantics/publishedVersio

Acute and Chronic Toxicity of Selected Cadmium Salts on Earthworm Eisenia andrei under Tropical Conditions

Agrochemicals and other hazardous chemicals are well known threats to healthy soil ecosystems. Fertilizers containing cadmium as an impurity are being added extensively to agricultural soils in Sri Lanka. These impurities may have hazardous impacts on soil ecosystems. Therefore toxicity of Cadmium Chloride (CdCl2) and Cadmium Sulphate (CdSO4) on survival, growth and reproduction of the earthworm Eisenia andrei were investigated under tropical conditions. The standard earthworm toxicity tests were performed according to the guidelines developed by ISO (International Organization for Standardization) and OECD (Organization for Economic Co-Operation and Development). Field collected natural soils were used as the test substrates. The endpoints measured were survival, growth and reproduction together with behavioral effects. Coiling, secretion of mucus and hypersensitivity were noted as common behavioral effects, which was observed in the highest concentrations in both cadmium salts. In terms of survival, both cadmium salts were not toxic to earthworm Eisenia andrei as LC50 were >1000 mg a.i /Kg dry soil. However, the chronic toxicity of cadmium chloride and cadmium sulphate was extremely high. Biomass reduction and reproduction were severely affected even at lower concentrations. The EC50 value for cadmium chloride and cadmium sulphate was 5.5 (2.6-8.4) mg a.i /kg dry soil and 6.3 (1.4-11.3) mg a.i /kg dry soil respectively. Lowest observed effect concentration (LOEC) for both salts was 1 mg a.i /Kg dry soil and No observed effect concentration (NOEC) was <1 mg a.i /Kg dry soil. Our study concludes that use of high Cd containing fertilizers may risk beneficial soil organisms and application should be done with caution.Keywords: Toxicity, Earthworm, Eisenia , Cadmiu

Hypothalamic Endoplasmic Reticulum Stress Of Overtrained Mice After Recovery

knowing the relationship between endoplasmic reticulum (ER) stress and inflammation and based on the fact that downhill running-based overtraining (OT) model increases hypothalamus levels of some pro-inflammatory cytokines, we verified the effects of three OT protocols on the levels of BiP, pIRE-1 (Ser734), pPERK (Thr981), pelF2alpha (Ser52), ATF-6 and GRP-94 proteins in the mouse hypothalamus after two weeks of recovery. Methods: the mice were randomized into control (CT), overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up) and overtrained by running without inclination (OTR) groups. After 2-week total recovery period (i.e., week 10), hypothalamus was removed and used for immunoblotting. Results: The OTR/down group exhibited high levels of BiP and ATF6. The other OT protocols showed higher levels of pPERK (Th981) and pelf-2alpha (Ser52) when compared with the CT group. Conclusion: The current results suggest that after a 2-week total recovery period, the overtrained groups increased partially their ER stress protein levels, but without hypothalamic inflammation, which characterizes a physiological condition related to an adaptation mechanism.2

Zooterapia amazônica: uso de gordura de sucuri ( Eunectes murinus ) como cicatrizante natural

Zootherapy (the use of the therapeutic potential of animals) is at least 6,000 years old, and has been kept active throughout generations until modern days. Animal fat is commonly used in the zootherapeutic folk medicine from South America, specially the green anaconda's fat, which is widely promoted as a natural medicine to treat wounds, even though there is no scientific evidence showing its efficacy. In this study we compared the total healing time and the proportional daily reduction of dorsal epithelial incisions in adult male Wistar rats treated with nitrofural (a commercial cicatrizing ointment) and with anaconda fat. We applied the treatments every two days and measured the incision diameter daily, during ten consecutive days. Differences among the groups in the total healing time and in the proportional daily reduction of the incision consistently showed that the fat-based treatment resulted in a faster healing process compared to the commercial ointment tested. The literature suggests that the efficacy of animal fat on healing may be primarily related to the presence of fatty acids, which have been widely demonstrated to be important for biochemical reactions involved in healing processes. Our findings are widely socially relevant, considering that traditional Amazonian communities that use anaconda fat in folk medicine do not have easy access to pharmacies and hospitals.Práticas ancestrais de zooterapia (uso das potencialidades terapêuticas da fauna) existem há pelo menos 6000 anos, e têm sido mantidas ao longo de gerações até os tempos modernos. Gordura de animais é comumente utilizada na zooterapia tradicional da América do Sul, e a gordura de serpentes sucuris é amplamente comercializada como cicatrizante natural, embora não existam evidências científicas que mostrem sua eficácia terapêutica. Neste estudo comparamos o tempo de cicatrização epitelial total e a redução proporcional diária de uma incisão dorsal em ratos Wistar machos adultos, entre um grupo controle, um grupo tratado com nitrofural (uma pomada cicatrizante comercial) e um grupo tratado com gordura de sucuri. Nós aplicamos os tratamentos a cada dois dias e medimos o diâmetro da incisão diariamente por dez dias consecutivos. Diferenças entre os grupos no tempo de cicatrização total e na redução proporcional diária da incisão consistentemente mostraram que gordura de sucuri teve ação cicatrizante mais eficiente que a pomada comercial testada. A literatura sugere que a eficácia de gordura animal em processos de cicatrização pode estar principalmente relacionada à presença de ácidos graxos, os quais têm sido amplamente demonstrados como importantes para reações bioquímicas envolvidas em processos de cicatrização. Os resultados têm ampla relevância social, considerando que as comunidades tradicionais amazônicas que utilizam a gordura de sucuris como zooterápico não têm acesso fácil a farmácias e hospitais

Acute and Chronic Toxicity of Selected Cadmium Salts on Earthworm Eisenia andrei under Tropical Conditions

Agrochemicals and other hazardous chemicals are well known threats to healthy soil ecosystems. Fertilizers containing cadmium as an impurity are being added extensively to agricultural soils in Sri Lanka. These impurities may have hazardous impacts on soil ecosystems. Therefore toxicity of Cadmium Chloride (CdCl2) and Cadmium Sulphate (CdSO4) on survival, growth and reproduction of the earthworm Eisenia andrei were investigated under tropical conditions. The standard earthworm toxicity tests were performed according to the guidelines developed by ISO (International Organization for Standardization) and OECD (Organization for Economic Co-Operation and Development). Field collected natural soils were used as the test substrates. The endpoints measured were survival, growth and reproduction together with behavioral effects. Coiling, secretion of mucus and hypersensitivity were noted as common behavioral effects, which was observed in the highest concentrations in both cadmium salts. In terms of survival, both cadmium salts were not toxic to earthworm Eisenia andrei as LC50 were >1000 mg a.i /Kg dry soil. However, the chronic toxicity of cadmium chloride and cadmium sulphate was extremely high. Biomass reduction and reproduction were severely affected even at lower concentrations. The EC50 value for cadmium chloride and cadmium sulphate was 5.5 (2.6-8.4) mg a.i /kg dry soil and 6.3 (1.4-11.3) mg a.i /kg dry soil respectively. Lowest observed effect concentration (LOEC) for both salts was 1 mg a.i /Kg dry soil and No observed effect concentration (NOEC) was <1 mg a.i /Kg dry soil. Our study concludes that use of high Cd containing fertilizers may risk beneficial soil organisms and application should be done with caution.Keywords: Toxicity, Earthworm, Eisenia , Cadmiu

The identification of sites of biodiversity conservation significance: progress with the application of a global standard

As a global community, we have a responsibility to ensure the long-term future of our natural heritage. As part of this, it is incumbent upon us to do all that we can to reverse the current trend of biodiversity loss, using all available tools at our disposal. One effective mean is safeguarding of those sites that are highest global priority for the conservation of biodiversity, whether through formal protected areas, community managed reserves, multiple-use areas, or other means. This special issue of the Journal of Threatened Taxa examines the application of the Key Biodiversity Area (KBA) approach to identifying such sites. Given the global mandate expressed through policy instruments such as the Convention on Biological Diversity (CBD), the KBA approach can help countries meet obligations in an efficient and transparent manner. KBA methodology follows the well-established general principles of vulnerability and irreplaceability, and while it aims to be a globally standardized approach, it recognizes the fundamental need for the process to be led at local and national levels. In this series of papers the application of the KBA approach is explored in seven countries or regions: the Caribbean, Indo-Burma, Japan, Macedonia, Mediterranean Algeria, the Philippines and the Upper Guinea region of West Africa. This introductory article synthesizes some of the common main findings and provides a comparison of key summary statistics