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Open access

Katarzyna Marcinkowska and Agnieszka Łacka

Summary

The effective dose of six herbicidal ionic liquids containing glyphosate [N-(phosphonomethyl)glycine] was investigated. Varied biological activity of the tested compounds was observed depending on the type of cation and targeted plant species. In the case of common lambsquarters, the lowest effective dose was obtained for compounds containing didecyldimethylammonium and di(hydrogenated tallow) dimethylammonium cations. In the case of white mustard, the lowest ED50 and ED90 values were obtained for the reference compound, which contained glyphosate isopropylamine salt. These parameters were determined using dose efficiency curves based on log-logistic models with three or four parameters. The study indicates that ionic liquids with glyphosate may be used as a new form of this herbicide in the future.

Open access

Severino Pinto, Gundula Hoffmann, Christian Ammon, Wolfgang Heuwieser, Harel Levit, Ilan Halachmi and Thomas Amon

Abstract

The aim of this study was to evaluate the effects of evaporative cooling at two different frequencies per day on the respiration rate (RR) of lactating dairy cows, considering cow-related factors. Twenty multiparous Israeli Holstein dairy cows housed in a naturally ventilated cowshed were divided randomly into two treatment groups. The cows of both groups were exposed to 3 or 8 cooling sessions per day (3xcool vs. 8xcool, respectively). The RR was observed hourly, with a maximum of 12 measurements per day. Body posture (standing vs. lying) was simultaneously documented. Milk yield was recorded daily. Coat color was determined from a digital photograph. The RR of standing and lying cows was lower in the 8xcool group (60.2 and 51.6 breaths per min (bpm), respectively) than in the 3xcool group (73.1 and 65.6 bpm, respectively). For each increment of five kilograms of milk produced, RR increased by one bpm, and the RR of cows in early DIM was 12.3 bpm higher than that of cows in late DIM. In conclusion, eight cooling sessions per day instead of three lead to a RR abatement in heat-stressed cows under hot conditions, and cow-related factors directly impact the RR during heat stress assessment.

Open access

Raid Ramzi Al-Omari, Madhat Shakir Al-Soud and Osamah Ibrahim Al-Zuhairi

Abstract

Tunnel construction below or adjacent to piles will affect the performance and eventually the stability of piles due to ground deformation resulting in the movement of piles and changes in the axial force distribution along the piles. A three dimensional finite element analysis using PLAXIS 3D (2013) was performed to study the behaviour of a single pile and 3 x 3 piles group during the advancement of shield tunnelling in ground. The 10-node tetrahedral elements were used to model both the soil and the tunnel lining. The Hardening Soil (HS) model was used to simulate the soil structure interaction at the tunnel-soil interface. An isotropic elastic model was used for the pile, piles cap, tunnel lining and tunnel boring machine shield (TBM). Several parametric studies were attempted including the longitudinal, lateral, and vertical tunnel location relative to pile embedded in different types of soil (clay or sand). The results showed that the pile head settlement increases during the tunnelling advancement in larger values than that for ground surface settlement. A zone of influence was determined in the range of twice the tunnel diameter in the longitudinal direction (forward and backward of the pile), and transverse direction (left and right of the tunnel centreline). If the tunnel boring is kept off this zone then there is no fear of pile collapse.

Open access

Marek Lecewicz, Rafał Strzeżek, Anna M. Majewska, Piotr S. Purpurowicz and Władysław Kordan

Abstract

Artificial insemination (AI) and semen cryopreservation are the most accessible and commonly used techniques for breeding domestic animals. Among many parameters, such as plasma membrane integrity and acrosome structure, one of key factor that determine the quality of frozen-thawed samples for artificial insemination is sperm motility. Sperm motility is one of the key parameters that determine the quality of frozen-thawed samples for AI. The total number of progressively motile spermatozoa in thawed canine semen is correlated with fertility. A variety of substances were used to compare sperm motility with the control. The aim of this study was to determine the effect of semen extender supplementation with motility stimulants, pentoxifylline (PTX), caffeine (CAF) and 2’-deoxyadenosine (DX), after different post-thaw incubation times (30, 60, 120 min) on the motility, selected kinematic parameters, plasma membrane integrity and mitochondrial membrane potential of cryopreserved canine spermatozoa. During attempts to improve the quality of cryopreserved semen, the applied substances exerted beneficial effects at a concentration of 10 mM. We demonstrated that both phosphodiesterase inhibitors, caffeine and pentoxifylline, as well as 2’-deoxyadenosine increased the motility and selected kinematic parameters of thawed canine spermatozoa.

Open access

Arnfinn H. Midtbøen

Abstract

This article uses the case of Denmark to critically discuss key assumptions in the theoretical literature on dual citizenship. When Denmark surprisingly accepted dual citizenship in 2015, the decision reflected two distinct lines of argument: first, accepting dual citizenship would allow Danes living abroad to keep their Danish citizenship; second, because it is considered illegitimate to make people stateless, allowing dual citizenship would simultaneously allow for citizenship revocation of dual citizens who engage in or support acts of terror. This rationale stands in striking contrast to how dual citizenship has been previously theorised. The gradual acceptance of dual citizenship in Western countries since the early 1990s has been seen either as a symptom of a post-national era or as a pragmatic adjustment to the transnational realities of international migration. By contrast, the case of Denmark shows that dual citizenship may serve as a lever to protect the political community of the nation-state from terrorism and, as such, function as a tool of securitisation.

Open access

Matija Zorc, Aleš Nagode, Milan Bizjak and Borut Zorc

Abstract

In production it is necessary to achieve conditions that lead to the minimum decarburization of a steel product’s surfaces. In this study, the hypo-eutectoid carbon steel C45 was annealed in air in the temperature range T a = 600–1100 °C. The annealing times were between t a = ½ h and t a = 2 h. Different decarburizations occurred in different microstructures: ferrite–pearlite (T a = 600°C and 700 °C, T a < AC1, no visible decarburization); ferrite–austenite (T a = 760 °C, AC1 < Ta < AC3, visible decarburization); austenite at the beginning, ferrite–austenite after the incubation period (Ta = 850 °C, AC3 < T a < 912 °C, visible decarburization); and austenite (T a = 950 °C and 1100 °C, T a > 912 °C, visible decarburization and overheating of steel). The edges were more prone to decarburization and to overheating. Stress relieving, normalizing and annealing before quenching of the steel C45 can be carried out in air.

Open access

Tuuli Kurki, Kristiina Brunila and Elina Lahelma

Abstract

The focus of this paper is to examine how immigrants become constituted as ideal care workers in educational settings. By analysing the everyday practices in two educational contexts in the Helsinki metropolitan area, Finland, the authors explore how these practices that are influenced by the national and transnational immigration and integration policy, regardless of their well-meant actions, can gender and racialise students with immigrant status.

Open access

M. Davarpanah, G. Somodi, L. Kovács and B. Vásárhelyi

Abstract

Understanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of correlations between the engineering properties of intact rock has always been the scope of experimental research, driven by the need to depict the actual behaviour of rock and to calculate most accurately the design parameters. To determine the behaviour of intact rock, the value of important mechanical parameters such as Young’s modulus (E), Poisson’s ratio (ν) and the strength of rock (σcd) was calculated. Recently, for modelling the behaviour of intact rock, the crack initiation stress (σci) is another important parameter, together with the strain (σ). The ratio of Young’s modulus and the strength of rock is the modulus ratio (M R), which can be used for calculations. These parameters are extensively used in rock engineering when the deformation of different structural elements of underground storage, caverns, tunnels or mining opening must be computed. The objective of this paper is to investigate the relationship between these parameters for Hungarian granitic rock samples. To achieve this goal, the modulus ratio (M R = Ec) of 50 granitic rocks collected from Bátaapáti radioactive waste repository was examined. Fifty high-precision uniaxial compressive tests were conducted on strong (σc >100 MPa) rock samples, exhibiting the wide range of elastic modulus (E = 57.425–88.937 GPa), uniaxial compressive strength (σc = 133.34–213.04 MPa) and Poisson’s ratio (ν = 0.18–0.32). The observed value (M R = 326–597) and mean value of M R = 439.4 are compared with the results of similar previous researches. Moreover, the statistical analysis for all studied rocks was performed and the relationshipbetween M R and other mechanical parameters such as maximum axial strain (εa,max)for studied rocks was discussed.

Open access

Elżbieta D. Ryńska and Maria L. Lewicka

Abstract

Sustainable development has now become an element that is deeply integrated in contemporary architectonic design and urban planning. With the development of a modern designer’s workshop, resilience, passive, ecological, plus energy or nZEB buildings and various smart city issues have to be included in line with more conventional analyses prepared during the design processes. Currently, we also face the emerging theme of the circular economy. This has a great impact, not just on the introduction of circular loops into the flow of building materials, but also on the design approach and management choices. Historic heritage buildings forming part of the building stock must be considered within this new theme. Most existing research deals either with new or modernised buildings, or with the re-use flows of various materials, actually often coming from historic buildings which have passed beyond the limits of repair. This paper shows a different approach to historic buildings where a design was prepared focusing on best choice cases and included a chain of several intertwining approaches, presented against the background of a Polish case study in Warsaw. The aim of this work is to propose a design management procedure to be used when dealing with historic buildings. It follows both the path of a circular economy and of heritage values, emphasising the need to maintain as much of the existing fabric as possible. This analysis is also based on various issues of site research and is followed by historic building case analysis.

Open access

Anna Mastalerz

Abstract

This paper deals with the transformations of (post)industrial towns in Poland, which took place during the transition from a centralised communist economy to liberal capitalism. As a consequence, a number of areas became redundant. These malfunctioning spaces represent serious spatial, social and economic problems. The complex multifaceted nature of towns means, however, that there were no simple solutions leading to immediate improvements. Investments focused on particular, isolated areas appeared to be far from sufficient interventions. Therefore, comprehensive programmes aimed at holistic urban regeneration are more common nowadays. Since local community wellbeing is one of the key factors in these renewal schemes, social participation is a crucial part of the process. This allows residents to have an influence on the regeneration of their town, which (if well carried out) is expected to improve space, economy and quality of life. The above-mentioned issues will be analysed on the basis of a case study of Pabianice, a post-industrial town in the province of Lodz. The aim of this study is to examine the social participation initiatives implemented during the preparation of the Regeneration Programme for Pabianice – to classify them and to compare them with models regarding the level of social involvement and power in the urban regeneration process described in the paper.