957 resultados para Cut knives
Resumo:
Objective: To study the anisotropic mechanical properties of the thoracic aorta in porcine. Methods: Twenty-one porcine thoracic aortas were collected and categorized into three groups. The aortas were then cut through in their axial directions and expanded into two-dimensional planes. Then, by setting the length direction of the planar aortas (i.e., axial directions of the aortas) as 0°, each planar aorta was counterclockwisely cut into 8 samples with orientation of 30°, 45°, 60°, 90°, 120°, 135°, 150° and 180°, respectively. Finally, the uniaxial tensile tests were applied on three groups of samples at the loading rates of 1, 5 and 10 mm/min, respectively, to obtain the elastic modulus and ultimate stress of the aorta in different directions and at different loading rates. Results: The stress-strain curves exhibited different viscoelastic behaviors. With the increase of sample orientations, the elastic modulus gradually increased from 30°, reached the maximum value at 90°, and then gradually decreased till 180°. The variation trend of ultimate stress was similar to that of elastic modulus. Moreover, different loading rates showed a significant influence on the results of elastic modulus and ultimate stress, but a weak influence on the anisotropic degree. Conclusions: The porcine thoracic aorta is highly anisotropic. This research finding provides parameter references for assignment of material properties in finite element modeling, and is significant for understanding biomechanical properties of the arteries.
Resumo:
Nonlinear absorption and refraction phenomena in stoichiometric lithium niobate (SLN) pure and co-doped with Zn and Nd, and congruent lithium niobate (CLN) were investigated using Z-scan technique. Femtosecond laser pulses from Ti:Sapphire laser (800 nm, 110 fs pulse width and 1 kHz repetition rate) were utilized for the experiment. The process responsible for nonlinear behavior of the samples was identified to be three photon absorption (3PA). This is in agreement with the band gap energies of the samples obtained from the linear absorption cut off and the slope of the plot of Ln(1 − TOA) vs. Ln(I0) using Sutherland’s theory (s = 2.1, for 3PA). The nonlinear refractive index (n2) of Zn doped samples was found to be lower than that of pure samples. Our experiments show that there exists a correlation between the nonlinear properties and the stoichiometry of the samples. The values of n2 fall into the same range as those obtained for the materials of similar band gap.
Resumo:
I-Methylcyclopropene (1-MCP) has the potential in tomato to reduce ethylene-associated changes in texture. Tomato cv. 'Revolution' was harvested at the 'pink' maturity stage and whole fruit treated with 0, 0.1, 1.0 or 10.0 µL.L-' 1-MCP at 20 "C for 12 h. Slices of 7-mm thickness were cut using a commercial slicer, and the slices stored in vertical stacks in plastic containers at 5°C for 7 days. The application of 1-MCP reduced both ethylene production and respiration rate of slices and resulted in firmer pericarp firmness. Ethylene production was 24%, 40%, and 62% lower following 0.1, 1.0, 10.0 µL L-' 1-MCP, respectively, compared with controls. In addition, respiration rate was reduced 6%, 10% and 20% by those 1-MCP treatments. 1-MCP treatments produced 20%, 34%, and 24% higher pericarp firmness, respectively, than in fruit not treated with 1-MCP.
Resumo:
Ethylene production is stimulated during the slicing of fresh cut tomato slices. Experiments were conducted to investigate whether the inclusion of ethylene absorbents in packaging affects the quality of tomato slices cv. Revolution during storage at 5OC. ‘Pink’ maturity stage tomatoes were cut into 7mm thick slices and vertically stacked in closed glass containers for 12 days with or without Purafil® to remove ethylene. The ethylene removal treatment resulted in reduced ethylene, less CO2 accumulation, and firmer slices.
Resumo:
In open-cut strip mining, waste material is placed in-pit to minimise operational mine costs. Slope failures in these spoil piles pose a significant safety risk to personnel, along with a financial risk from loss of equipment and scheduling delays. It has been observed that most spoil pile failures occur when the pit has been previously filled with water and then subsequently dewatered. The failures are often initiated at the base of spoil piles where the material can undergo significant slaking (disintegration) over time due to overburden pressure and water saturation. It is important to understand how the mechanical properties of base spoil material are affected by slaking when designing safe spoil pile slope angles, heights, and dewatering rates. In this study, fresh spoil material collected from a coal mine in Brown Basin Coalfield of Queensland, Australia was subjected to high overburden pressure (0 – 900 kPa) under saturated condition and maintained over a period of time (0 – 6 months) allowing the material to slake. To create the above conditions, laboratory designed pressure chambers were used. Once a spoil sample was slaked under certain overburden pressure over a period of time, it was tested for classification, permeability, and strength properties. Results of this testing program suggested that the slaking of saturated coal mine spoil increase with overburden pressure and the time duration over which the overburden pressure was maintained. Further, it was observed that shear strength and permeability of spoil decreased with increase in spoil slaking.
Resumo:
THE rapid development of recombinant DNA technology has brought forth a revolution in biology'>", it aids us to have a closer look at the 'way genes are organized, eS11 ecially in the complex eucaryotic genornes'<", Although many animal and yeast genes have been studied in detail using recombinant DNA technology, plant genes have seldom been targets for such studie., Germination is an ideal process to study gene expression .because it effects a . shift in the metabolic status of seeds from a state of 'dormancy to an active one. AJ;l understanding of gene organization and regulation darin.g germination can be accomplblted by molecular cloning of DNA from seeds lik.e rice. To study the status of histone, rRNA tRNA and other genes in the rice genome, a general method was developed to clone eucarvotic DNA in a' plasmid vector pBR 322. This essentially ~ involves the following steps. The rice embryo and plasmid pBR 322 DNAs were cut witll restriction endonuclease Bam Hi to generate stick.Y ends, The plasmid DNA was puosphatased, the DNA~ ware a~·tnealed and joined 'by T4 phage DNA ligase. The recombinant DNA molecules thus produced were transjerred into E. coli and colonies containing them Were selected by their sensitivity to tetracycline and resistance to ampicillin, Two clones were identified . 2S haVing tRNA genes by hybridization of the DNA in the clones \vitl1 32P-la.belled rice tRNAs.
Resumo:
Maintenance of quality, such as firmness, is important during storage of fresh cut produce. This study compared the effects of I-MCP on the quality of tomato slices when intact tomatoes were treated with 1-MCP and then sliced, or tomatoes were sliced and the slices treated with I-MCP. In both instances the MCP treatment was 1 µL Lˉٰ at 20 ºC for 12 h. Tomato cv. 'Revolution' was harvested at the 'pink' stage of maturity, cut into 7-mm slices, and stored as vertical stacks in closed plastic containers at 5ºC for up to 7 days after the 1-MCP treatment. Exposure of intact tomatoes to I-MCP resulted in reduced ethylene production (31%) and firmer (22%) slices than when tomatoes were not I-MCP treated. The application of I-MCP prior to slicing of tomatoes appears a useful strategy to retain quality of stored tomato slices.
Resumo:
A summer grown forage legume crop – Lablab (Lablab purpureus) harvested in autumn, was ensiled as plastic wrapped, large round bales. Of the 30 bales produced, 13 were inoculated with a bacterial inoculant containing Lactobacillus plantarum and Enterococcus faecium. Inoculant was premixed at 30 g/litre water, cultured overnight (18 hours) then sprayed onto cut forage during the baling and wrapping procedure at 1 litre per tonne of silage. A replicated feeding experiment was conducted in July - August 1998 (5 weeks), using 24 eight month old Holstein Friesian heifers group fed non-inoculated or inoculated silage to appetite plus 2 kg rolled sorghum grain/heifer.day. Chemical composition and nutritive value of well preserved bales of control and inoculated silages were similar (P>0.05) with 50% DM and 26 g N and 6.8 MJ ME per kg DM. Lactic acid and acetic acid concentrations were 11.4 v. 11.4 and 4.90 v. 3.75 g/kg DM for control and inoculated silages respectively (P>0.05). Heifers preferentially selected leaf from the silage offered and maintained liveweight gains of 0.70 and 0.61 kg/day respectively (P>0.05) during the silage feeding period. High DM and low WSC content of the parent forage may have reduced the opportunity for the bacterial inoculant to have effect. Animal production for a consuming world : proceedings of 9th Congress of the Asian-Australasian Association of Animal Production Societies [AAAP] and 23rd Biennial Conference of the Australian Society of Animal Production [ASAP] and 17th Annual Symposium of the University of Sydney, Dairy Research Foundation, [DRF]. 2-7 July 2000, Sydney, Australia.
Resumo:
Surface composition and depth profile studies of hemiplated thin film CdS:CuzS solar cells have been carried out using x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) techniques. These studies indicate that the junction is fairly diffused in the as-prepared cell. However, heat treatment of the cell at 210°C in air relatively sharpens the junction and improves the cell performance. Using the Cu(2p3p)/S(2p) ratio as well as the Cu(LVV)/(LMM) Auger intensity ratio, it can be inferred that the nominal valency of copper in the layers above the junction is Cut and it is essentially in the CUSS form. Copper signals are observed from layers deep down in the cell. These seem to appear mostly from the grain boundary region. From the observed concentration of Cd, Cu and S in these deeper layers and the Cu(LVV)/(LMM) ratio it appears that the signals from copper essentially originate partly from copper in CuS and partly from Cu2t trapped in the lattice. It is significant to note that the nominal valence state of copper changes rather abruptly from Cut to Cuz+ across the junction.
Resumo:
The widespread and increasing resistance of internal parasites to anthelmintic control is a serious problem for the Australian sheep and wool industry. As part of control programmes, laboratories use the Faecal Egg Count Reduction Test (FECRT) to determine resistance to anthelmintics. It is important to have confidence in the measure of resistance, not only for the producer planning a drenching programme but also for companies investigating the efficacy of their products. The determination of resistance and corresponding confidence limits as given in anthelmintic efficacy guidelines of the Standing Committee on Agriculture (SCA) is based on a number of assumptions. This study evaluated the appropriateness of these assumptions for typical data and compared the effectiveness of the standard FECRT procedure with the effectiveness of alternative procedures. Several sets of historical experimental data from sheep and goats were analysed to determine that a negative binomial distribution was a more appropriate distribution to describe pre-treatment helminth egg counts in faeces than a normal distribution. Simulated egg counts for control animals were generated stochastically from negative binomial distributions and those for treated animals from negative binomial and binomial distributions. Three methods for determining resistance when percent reduction is based on arithmetic means were applied. The first was that advocated in the SCA guidelines, the second similar to the first but basing the variance estimates on negative binomial distributions, and the third using Wadley’s method with the distribution of the response variate assumed negative binomial and a logit link transformation. These were also compared with a fourth method recommended by the International Co-operation on Harmonisation of Technical Requirements for Registration of Veterinary Medicinal Products (VICH) programme, in which percent reduction is based on the geometric means. A wide selection of parameters was investigated and for each set 1000 simulations run. Percent reduction and confidence limits were then calculated for the methods, together with the number of times in each set of 1000 simulations the theoretical percent reduction fell within the estimated confidence limits and the number of times resistance would have been said to occur. These simulations provide the basis for setting conditions under which the methods could be recommended. The authors show that given the distribution of helminth egg counts found in Queensland flocks, the method based on arithmetic not geometric means should be used and suggest that resistance be redefined as occurring when the upper level of percent reduction is less than 95%. At least ten animals per group are required in most circumstances, though even 20 may be insufficient where effectiveness of the product is close to the cut off point for defining resistance.
Resumo:
Bertrand Russell (1872 1970) introduced the English-speaking philosophical world to modern, mathematical logic and foundational study of mathematics. The present study concerns the conception of logic that underlies his early logicist philosophy of mathematics, formulated in The Principles of Mathematics (1903). In 1967, Jean van Heijenoort published a paper, Logic as Language and Logic as Calculus, in which he argued that the early development of modern logic (roughly the period 1879 1930) can be understood, when considered in the light of a distinction between two essentially different perspectives on logic. According to the view of logic as language, logic constitutes the general framework for all rational discourse, or meaningful use of language, whereas the conception of logic as calculus regards logic more as a symbolism which is subject to reinterpretation. The calculus-view paves the way for systematic metatheory, where logic itself becomes a subject of mathematical study (model-theory). Several scholars have interpreted Russell s views on logic with the help of the interpretative tool introduced by van Heijenoort,. They have commonly argued that Russell s is a clear-cut case of the view of logic as language. In the present study a detailed reconstruction of the view and its implications is provided, and it is argued that the interpretation is seriously misleading as to what he really thought about logic. I argue that Russell s conception is best understood by setting it in its proper philosophical context. This is constituted by Immanuel Kant s theory of mathematics. Kant had argued that purely conceptual thought basically, the logical forms recognised in Aristotelian logic cannot capture the content of mathematical judgments and reasonings. Mathematical cognition is not grounded in logic but in space and time as the pure forms of intuition. As against this view, Russell argued that once logic is developed into a proper tool which can be applied to mathematical theories, Kant s views turn out to be completely wrong. In the present work the view is defended that Russell s logicist philosophy of mathematics, or the view that mathematics is really only logic, is based on what I term the Bolzanian account of logic . According to this conception, (i) the distinction between form and content is not explanatory in logic; (ii) the propositions of logic have genuine content; (iii) this content is conferred upon them by special entities, logical constants . The Bolzanian account, it is argued, is both historically important and throws genuine light on Russell s conception of logic.
Resumo:
"We have neither Eternal Friends nor Eternal Enemies. We have only Eternal Interests .Finland's Relations with China 1949-1989 The study focuses on the relations between Finland and the People s Republic of China from 1949-1989 and examines how a small country became embroiled in international politics, and how, at the same time, international politics affected Finnish-Chinese relations and Finland s China policy formulation. The study can be divided into three sections: relations during the early years, 1949-1960, before the Chinese and Soviet rift became public; the relations during the passive period during the 1960s and 1970s; and the impact of China s Open Door policy on Finland s China policy from 1978-1989. The diplomatically challenging events around Tiananmen Square and the reactions which followed in Finland bring the study to a close. Finland was among the first Western countries to recognise the People s Republic and to establish diplomatic relations with her, thereby giving Finland an excellent position from which to further develop good relations. Finland was also the first Western country to sign a trade agreement with China. These two factors meant that Finland was able to enjoy a special status with China during the 1950s. The special status was further strengthened by the systematic support of the government of Finland for China's UN membership. The solid reputation earned in the 1950s had to carry Finland all the way through to the 1980s. For the two decades in between, during the passive policy period of the 1960s and 1970s, relations between Finland and the Soviet Union also determined the state of foreign relations with China. Interestingly, however, it appeared that President Urho Kekkonen was encouraged by Ambassador Joel Toivola to envisage a more proactive policy towards China, but the Cultural Revolution cut short any such plan for nearly twenty years. Because of the Soviet Union, Finland held on to her passive China policy, even though no such message was ever received from the Soviet Union. In fact, closer relationships between Finland and China were encouraged through diplomatic channels. It was not until the presidency of Mauno Koivisto that the first high-level ministerial visit was made to China when, in 1984, Foreign Minister Paavo Väyrynen visited the People s Republic. Finnish-Chinese relations were lifted to a new level. Foreign Minister Väyrynen, however, was forced to remove the prejudices of the Chinese. In 1985, when the Speaker of the Finnish Parliament, Erkki Pystynen visited China he also discovered that Finland s passive China policy had caused misunderstandings amongst the Chinese politicians. The number of exchanges escalated in the wake of the ground-breaking visit by Foreign Minister Väyrynen: Prime Minister Kalevi Sorsa visited China in 1986 and President Koivisto did so in 1988. President Koivisto stuck to practical, China-friendly policies: his correspondence with Li Peng, the attitude taken by the Finnish government after the Tiananmen Square events and the subsequent choices made by his administration all pointed to a new era in relations with China.
Resumo:
In 1952 Helsinki hosted the Summer Olympic Games and Armi Kuusela, the current “Maiden of Finland”, was at the same time crowned Miss Universe. In popular history writing, these events have been designated as a crucial turning point – the end of an era marked by war and deprivation and the beginning of a modern, Western nation. Symptomatically, both events were marked by Finnish women’s sexual relationships with foreign men. The Olympics were shadowed by a concern over Finnish women’s “undue friendliness” with the Olympic guests, and Armi Kuusela's world tour was cut short by her surprise marriage in Tokyo and subsequent emigration to the Philippines. This study is an inquiry into the Helsinki Olympics and the public persona of Armi Kuusela from the point of view of transnational heterosexuality and the constitution of Finnish national identity. Methodologically the two main components of the study are intersectionality, defined here as a focus on the mutual histories and effects of discourses of gender, sexuality, race and nation; and transnational history as a way of exploring the ways that both nations and sexual subjects are embedded in global relations of power. The analysis proceeds by way of contextual and intertextual readings of various sources. Part one, centering on the Olympics, involves a campaign mounted by certain women’s organizations before the Games in order to educate young women about the potential dangers of the forthcoming international event as well as magazine and newspaper articles published during and after the Games concerning the encounter between young Finnish women and foreign, especially “Southern,” men. It places the debates during the Olympics within the framework of wartime understandings of women’s sexuality; the history of the concept of decency (siveellisyys); post-war population policy; the intersectional histories of conceptions pertaining to race and sexuality; and finally, the post-war concerns over women’s migration from rural areas to the capital city and their potential emigration abroad. Part two deals with the persona of Armi Kuusela and the public reception of her world tour and marriage, based on material from both Finland and the Philippines (newspapers, magazines, advertisements, books and films). It examines the persona of Armi Kuusela as a figure of national import in terms of the East/West divide; the racialized images of different geographic climates and Oriental “Others;” the meaning of whiteness in the Philippines; the significance of class and colonial history for the domestication of sexual and racial transgressions implied by an unconventional transnational marriage; as well as the cultural logics of transnational desire and its possible meanings for women in 1950s Finland. The study develops two arguments. First, it suggests that instead of being purely oppositional to national discourses, transnational desire may also be viewed as a product of these very discourses. Second, it claims that the national significance of both the Olympics and the persona of Armi Kuusela was due to the new points of comparison they both offered for national identity construction. In comparison with the sexualized Southern men at the Olympics and the racialized Orient in the representations of Armi Kuusela’s travels and marriage, Finland emerged as part of the civilized North, placed firmly within the perimeters of Western Europe. As such, both events mark a “whitening” of the Finnish people as well as a distancing from their previous designations in racial hierarchies. At the same time, however, the process of becoming a white nation inevitably meant complying with and reproducing racial hierarchies, rather than simply abolishing them.
Resumo:
Bestiality was in the 18th century a more difficult problem in terms of criminal policy in Sweden and Finland than in any other Christian country in any other period. In the legal history of deviant sexuality, the phenomenon was uniquely widespread by international comparison. The number of court cases per capita in Finland was even higher than in Sweden. The authorities classified bestiality among the most serious crimes and a deadly sin. The Court of Appeal in Turku opted for an independent line and was clearly more lenient than Swedish courts of justice. Death sentences on grounds of bestiality ended in the 1730s, decades earlier than in Sweden. The sources for the present dissertation include judgment books and Court of Appeal decisions in 253 cases, which show that the persecution of those engaging in bestial acts in 18th century Finland was not organised by the centralised power of Stockholm. There is little evidence of local campaigns that would have been led by authorities. The church in its orthodoxy was losing ground and the clergy governed their parishes with more pragmatism than the Old Testament sanctioned. When exposing bestiality, the legal system was compelled to rely on the initiative of the public. In cases of illicit intercourse or adultery the authorities were even more dependent on the activeness of the local community. Bestiality left no tangible evidence, illegitimate children, to betray the crime to the clergy or secular authorities. The moral views of the church and the local community were not on a collision course. It was a common view that bestiality was a heinous act. Yet nowhere near all crimes came to the authorities' knowledge. Because of the heavy burden of proof, the legal position of the informer was difficult. Passiveness in reporting the crime was partly because most Finns felt it was not their place to intervene in their neighbours' private lives, as long as that privacy posed no serious threat to the neighbourhood. Hidden crime was at least as common as crime more easily exposed and proven. A typical Finnish perpetrator of bestiality was a young unmarried man with no criminal background or mental illness. The suspects were not members of ethnic minorities or marginal social groups. In trials, farmhands were more likely to be sentenced than their masters, but a more salient common denominator than social and economical status was the suspects' young age. For most of the defendants bestiality was a deep-rooted habit, which had been adopted in early youth. This form of subculture spread among the youth, and the most susceptible to experiment with the act were shepherds. The difference between man and animal was not clear-cut or self-evident. The difficulty in drawing the line is evident both in legal sources and Finnish folklore. The law that required that the animal partners be slaughtered led to the killing of thousands of cows and mares, and thereby to substantial material losses to their owners. Regarding bestiality as a crime against property motivated people to report it. The belief that the act would produce human-animal mongrels or that it would poison the milk and the meat horrified the public more than the teachings of the church ever could. Among the most significant aspects in the problems regarding the animals is how profoundly different the worldview of 18th century people was from that of today.
Resumo:
Gossypol, a polyphenolic compound isolated from cotton plant was found to degrade pBR322 DNA Image in a reaction which required the presence of a metal ion, a reducing agent (2-mercaptoethanol) and oxygen as revealed after agarose gel electrophoresis. Fe3+ and Co2+ showed maximum degradation whereas addition of Ca2+ and Mg2+ prevented the gossypol mediated DNA damage. Gossypol caused degradation of rat liver DNA incubated Image even in the absence of added metal ions and 2-mercaptoethanol. Incubation of intact rat liver nuclei with gossypol reveled DNA degradation and nuclei isolated from rats treated with gossypol Image showed higher succestibility to DNA fragmentation when incubated with gossypol Image than control nuclei. EcoRl and AIuI digestion of DNA isolated from gossypol treated rats gave clear cut evidence for DNA degradation. These observations indicate that gossypol is genotoxic and considereable care has to be exercised in its use. SDS, sodium dodecayl sulphate; TE buffer, Tris-HCL-EDTA buffer.