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Within the elastic range, the number of load-carrying fasteners in an interchangeable manufactured joint subjected to a shear load is dependent upon the following characteristics: 1. Material properties of the constituent parts in the shear joint. 2. Geometry of the shear joint. 3. Manufacturing tolerances of the constituent parts in the shear joint. 4. Number of fasteners in the shear joint. 5. Preload on the fasteners in the joint. 6. Static coefficient of friction between the joint surfaces. Neglecting the effects of preload and friction, the number of load-carrying fasteners is determined for a theoretical bolted joint design as a function of the remaining four (above) parameters. The analysis is accomplished by assuming all deformation in the constituent parts of the joint remain within the elastic range and then examining the stress-strain relationship existent in the shear joint. Based on simplifying assumptions, the total deflection is calculated and then, statistics are applied to the manufacturing tolerances of the constituent parts of the shear joint. The results suggest that plastic deformation occurs in all classically designed shear joints and the predicted number of load carrying fasteners using this analysis approach is in error. Suggestions for future research are presented.

Tardigrades are microscopic animals that can survive exposure to multiple extreme conditions. This remarkable ability makes them suitable laboratory model organisms for conducting biological to astrobiological research. Whereas tardigrade extreme-tolerance research has been focused predominantly on their ability to endure extreme desiccation, responses to other extraordinary conditions (i.e. hypergravity, pH, radiation and low temperature) remain un-described. These extreme tolerance research areas, in addition to life history traits, were documented in our studies on the eutardigrade species Hypsibius dujardini. We found that specimens tolerated extreme g-equivalent forces (i.e., 16060g) and radiation levels (i.e. 5 kGy), with decreased survivorship at increased accelerations and radiation doses. Radiation induced bystander effects (RIBEs) manifested as a threshold response, with the threshold value between 3 and 5 kGy. Extreme acidic (pH 1 and 2) and alkaline (pH 11 to 14) conditions caused death instantaneously, while exposures to pH 4, 6, 8, 9, and 10 were tolerated. Tardigrade eggs reared at 0 °C for 4 days developed relatively slowly, diminishing their biological age relative to their chronological age. Extending cold exposure (0 °C) time (days = 10, 20 and 40) decreased incubation time (days = 3, 2 and 1, respectively) at 22 °C; lengthening cold exposure time led to decreased growth in juveniles and lowered survivorship in adults, suggesting that costs are associated with increasing incubation time at 0 °C. Tolerance to hypergravity, large radiation doses and a wide-range in pH conditions support the notion that tardigrades are suitable organisms for astrobiological research, particularly in exploring parameters associated with potential transfer and habitability in extreme environments. RIBEs in adult tardigrades and the ability for tardigrade embryos to alter their ‘biological clocks’ based on exposed cold temperature duration have applications in biological research. Characterizing molecules involved in bystander signaling and response and biological clock adjustments during development could have important implications for improving biological practices such as radiotherapy and cryopreservation. / Thesis / Doctor of Philosophy (PhD) / While interest in tardigrade extreme tolerance research has increased over the last decade, many research areas continue to be underrepresented or non- existent. And, while recognized tardigrade species have been increasing steadily in number, fundamental biological details, like individual life history traits, remain unknown for most. The main objectives in this thesis therefore were to survey the life history traits for the freshwater tardigrade species Hypsibius dujardini, increase knowledge about its extreme-tolerance abilities and describe its utility in astrobiological and biological studies. Research involved tardigrade tolerance to hypergravity, pH levels and radiation exposure (and associated radiation-induced bystander effects) as well as responses to temperature changes during development. Findings reported in this dissertation provide new data about H. dujardini, thereby narrowing the information gap that currently exists in the literature for this species.

Researchers point to the fact that stress and anxiety among college students are a

Thesis (MSc. (Botany)) -- University of Limpopo, 2015 / Soybean is an important source of high quality protein and oil for both humans and animals, especially in protein formulations for pharmaceutical and nutriceutical use. This crop is adversely affected by both biotic and abiotic stresses impacting on its productivity. Soybean productivity can be improved via techniques such Agrobacterium-mediated genetic transformation. Soybean is recalcitrant and depends on suitable explants from which new shoots can be regenerated and be amenable for transformation. The goal of this study was to produce transgenic soybean plants that are tolerant to drought stress through Agrobacterium tumefaciens-mediated transformation. Multiple shoot induction on double and single coty-node explants, obtained from soybean seedlings derived from seeds germinated in vitro on Murashige and Skoog culture medium supplemented with cytokinins was studied. The effect of different concentrations of benzyladenine (1.57, 2.00 and 4.00 mg/l), and benzyladenine (2.00 mg/l) in combination with kinetin (1.00 mg/l) was tested. The results show that the double coty-node explants produce the highest number of shoots per explant, an average of 7.93 shoots on Murashige and Skoog medium supplemented with 2.00 mg/l benzyladenine. The lowest number being 1.87 shoots obtained from single coty-node explants cultured on Murashige and Skoog medium containing 4.00 mg/l benzyladenine. The single coty-node explants showed lower frequency (10–57%) of shoot induction when compared to the double coty-node explants (50–83%). The suitability of aminoglycoside antibiotics (hygromycin, tetracycline and rifampicin) for efficient elimination of Agrobacterium tumefaciens after co-cultivation was tested using a well agar diffusion assay. Co-culturing double coty-node explants with Agrobacterium containing pTF 101 vector carrying the Oryza cystatin 1 gene resulted in 76.6, 63.3 and 60.0% shoot regeneration on Murashige and Skoog shoot induction media (shoot induction medium 1, shoot induction medium 2 and shoot induction medium 3) containing hygromycin, tetracycline and rifampicin at 500 mg/l respectively. These antibiotics showed the highest zones of inhibition against pTF 101 using the well agar diffusion assay. On the other hand, 85% plant regeneration was obtained during in vivo transformation following Agrobacterium injection into seedlings. These results imply that vi both in vitro and in vivo protocols were suitable for transgenic shoot regeneration and plant establishment since all the plants continued surviving in the presence of 6.00 mg/l glufosinate-ammonium. Future work will focus on screening of transgenic plants using beta-glucuronidase and isolating the protein encoded by the Oryza cystatin 1 gene to further confirm the generation of transformed plants carrying the gene of interest.

The mechanism of drought resistance in the seedlings of Aleppo pine (Pinus halepensis) and Brutia pine (Pinus brutia) was investigated. Both species showed anatomical and morphological adaptations to conserve moisture. Aleppo pine had a thicker cuticle, fewer stomata per unit length, per unit area, and per needle than Brutia pine. A significant number of Aleppo pine stomata were sealed with a waxy layer. Brutia pine had shorter needles, smaller needle surface area, a smaller surface area-to-volume ratio, and longer main root length. The two species were similar in height growth and in the seasonal trend of total non-structural carbohydrates (reducing sugars and starch). Brutia pine had more reducing sugars and less starch in its shoots than Aleppo pine. The latter had a greater amount of total non-structural carbohydrates and starch when the seedlings were subjected to dry down moisture stress. Electron microscopy techniques were used to monitor ultrastructural changes in the chloroplasts of mesophyll cells. Aleppo pine was found to contain chloroplasts exhibiting water stress-related damage at a relative water content of 62 percent, where as Brutia pine chloroplasts were disrupted. It is suggested that future investigations examine the physiological manifestation of drought mechanism at the cellular and molecular levels of both species.

Magistro baigiamojo darbo tema „Paauglių tolerantiškas elgesys ir jo ugdymo galimybės mokykloje“ Lietuvos švietimo koncepcijoje (1992) bei Bendrojo lavinimo mokyklos bendrosiose programose ir išsilavinimo standartuose (2004) atkreipiamas dėmesys, kad tolerancija mokyklos gyvenime yra svarbi prielaida rengiant mokinius gyvenimui nuolat kintančioje aplinkoje, padedant jiems atrasti tinkamas saviraiškos, savęs realizavimo formas, taip pat ir skatinant brandžios, kūrybingos bei atsakingos asmenybės tapsmą. Tolerancija yra pripažįstama Europos ir Lietuvos dokumentuose kaip svarbi vertybė, tačiau ji neretai yra nepakankamai ugdoma mokykloje. Kita vertus, tyrimų, atskleidžiančių tolerancijos būklę, jos ugdymo galimybes, paauglystėje stinga. Tyrimo objektas. Paauglių tolerancijos ugdymo procesas mokykloje. Tyrimo tikslas. Atskleisti paauglių tolerancijos raiškos ypatumus ir ugdymo realybę mokykloje. Tyrimo metodika. Norint išsiaiškinti paauglių tolerancijos raiškos ypatumus ir ugdymo galimybes mokykloje, buvo atliktas kiekybinis tyrimas. Tyrimas vyko dvejose Telšių ir vienoje Šiaulių vidurinėse mokyklose. Iš viso dalyvavo 214 paauglių, iš jų 6-8 klasių mokiniai, bei 50 mokytojų. Tyrimo tikslui pasiekti bei hipotezei patvirtinti / paneigti naudojama anketinė apklausa, literatūros šaltinių analizė. Dauguma mokslininkų toleranciją apibūdina kaip žmogaus nuomonės, elgesio ar įsitikinimų gerbimą. Tačiau ši sąvoka dar apibūdinama kaip priemonę kito žmogaus palankumui įgyti, kaip būdą... [toliau žr. visą tekstą] / Topic of master’s final paper: Tolerant behaviour of teenagers and it’s education at school. Lithuanian Education Concept (1992) and General Programs and Education Standards of Mainstream Schools (2004) stress that tolerance in the school life is an important premise in preparing the pupils for life in a changing environment, assisting them in finding suitable self-expression and self-realization forms, also inducing their self-expression as well as matured, creative and responsible personality becoming. Tolerance is acknowledged in European and Lithuanian documents as an important value, however it often is underdeveloped at school. On the other hand, there is lack of the studies, disclosing the level of tolerance and its development opportunities in adolescence. Subject of the research. Teenager tolerance development process at school. Aim of the research. To disclose teenager tolerance development peculiarities and development reality at school. Methods of the research. In order to disclose teenager tolerance development peculiarities and development reality at school, quantitative survey was performed. It was performed in two secondary schools of Telsiai and one of Siauliai. In total 214 teenagers from 6th-8th forms and 50 teachers were interviewed. In order to reach aim of the research and to corroborate or reject the hypothesis questioning survey and analysis of written sources were applied. Most of the researchers define tolerance like respect of person’s opinion... [to full text]

Computer models of the geometry of the real world have a tendency to assume that the shapes and positions of objects can be described exactly. However, real surfaces are subject to irregularities such as bumps and undulations and so do not have perfect, mathematically definable forms. Engineers recognise this fact and so assign tolerance specifications to their designs. This thesis develops a representation of geometric tolerance and uncertainty in assemblies of rigid parts. Geometric tolerances are defined by tolerance zones which are regions in which the real surface must lie. Parts in an assembly can slop about and so their positions are uncertain. Toleranced parts and assemblies of toleranced parts are represented by networks of tolerance zones and datums. Each arc in the network represents a relationship implied by the tolerance specification or by a contact between the parts. It is shown how all geometric constraints can be converted to an algebraic form. Useful results can be obtained from the network of tolerance zones and datums. For example it is possible to determine whether the parts of an assembly can be guaranteed to fit together. It is also possible to determine the maximum slop that could occur in the assembly assuming that the parts satisfy the tolerance specification. Two applications of this work are (1) tolerance checking during design and (2) analysis of uncertainty build-up in a robot assembly plan. I n the former, a designer could check a proposed tolerance specification to make sure that certain design requirements are satisfied. In the latter, knowledge of manufacturing tolerances of parts being manipulated can be used to determine the constraints on the positions of the parts when they are in contact with other parts.

Master of Science / Department of Agronomy / S.V. Krishna Jagadish / Low temperature is one of the most limiting stresses to crops that are adapted to tropical and subtropical regions, such as maize (Zea mays L.) and sorghum [Sorghum bicolor (L.) Moench], when introduced into temperate regions. However, no studies have compared the chilling tolerance of maize and sorghum grown together. Therefore, the objective of this research was to screen maize hybrids and sorghum genotypes for chilling tolerance at the germination and seedling stages. With the hypothesis that grain composition of maize and sorghum could lead to varying chilling tolerance, the seeds were analyzed for concentrations of protein, starch, and amylose. Five commercial hybrids of maize and 18 genotypes of sorghum were maintained in growth chambers for 31 days at two temperatures: a control temperature (25/20 °C, day/night) and at chilling temperatures (11/8 °C for 14 days; 12.5/9.5 °C for 14 days, and 14/11 °C for 3 days). Emergence and seedling height were measured during the experiment. At the end of the experiment, shoot dry weight, root dry weight, and leaf area were determined. Emergence of sorghum under the chilling temperature regime was low (18%). Average height of the emerged sorghum seedlings in the cold temperatures at the end of the experiment was 1.4 cm compared to 55.5 cm in the control treatment. All maize hybrids emerged, but emergence and growth were slowed by the cold temperatures, and average height at the end of the experiment was 4.6 cm compared to 96.1 cm in the control treatment. Shoot dry weight, root dry weight, and leaf area of the sorghum under the chilling temperatures were too small to measure, and, for maize, they were greatly reduced. The results showed that, for sorghum, temperatures should be above 14 °C for emergence, while maize could emerge at lower temperatures. The analyses of the sorghum seeds showed that Redbine 60 and RTx430 had the highest protein concentrations (15.71% and 15.35%, respectively), and Segaolane had the lowest protein concentration (9.83%). Segaolane had the highest starch concentration (72.71%), and RTx430 had the lowest starch concentration (65.31%). There was an inverse relationship between protein and starch concentrations in the sorghum seeds (R2 = 0.69). Amylose concentrations did not vary significantly among the sorghum seeds. The analyses of the maize seeds showed that Dekalb 51-20 and Pioneer 1151 had the highest protein concentrations (10.98% and 10.95%, respectively), and Pioneer 1105 had the lowest protein concentration (9.26%). Starch and amylose concentrations did not vary significantly among the maize seeds.

La laïcité est considérée comme un pilier du modèle républicain français et est, aujourd’hui, utilisée en tant que modèle d’intégration concernant les immigrés et les minorités culturelles et religieuses en France. Les travaux en psychologie sociale étudiant l’impact de l’adhésion au principe de laïcité sur les relations intergroupes révèlent que ce principe prédit négativement la tolérance envers la diversité culturelle. Cependant, de nombreux sociologues, politologues et historiens s’accordent à dire que la laïcité, telle qu’elle est conçue aujourd’hui, ne correspond pas à ce qu’elle était initialement, au moment de la création de la Loi de Séparation des Eglises et de l’Etat, en 1905. Il semblerait donc qu’il existe, non pas une laïcité, mais plusieurs conceptions de celle-ci. L’objectif de cette thèse se décline en trois axes de recherche : le premier est de construire une échelle permettant de prendre en compte les différentes croyances de la laïcité ; le deuxième est d’étudier, dans quelle mesure, l’adhésion aux différentes croyances sous-jacentes à la laïcité est liée à plus ou moins de tolérance envers la diversité culturelle ; le troisième est d’étudier comment l’adhésion aux différentes dimensions sous-jacentes à la laïcité prédit plus ou moins de tolérance envers la diversité religieuse. Globalement, les résultats indiquent qu’il existe différentes conceptions de la laïcité, permettant soit de promouvoir la tolérance envers la diversité culturelle et religieuse, soit, au contraire, d’atténuer la tolérance envers la diversité culturelle et religieuse. Les apports de ce travail, tant au niveau de la recherche, qu’au niveau sociétal sont discutés lors de la conclusion générale / Laïcité is considered a pillar of the French Republican model and is used, today, as a model of integration concerning immigrants and cultural and religious minorities in France. Research in socialpsychology studying the impact of support for the principle of laïcité on intergroup relations reveal that this principle negatively predicts the tolerance of cultural diversity. However, many sociologists, political analysts and historians agree to say that laïcité, as it is understood today, does not correspond to its initial definition, at the time of the creation of the law of Separation of Churches and the State, in 1905. Thus, it would seem that several, not only one, conceptions of laïcité exit. The objective of this thesis is to highlight the different conceptions of laïcité, and to study, to what extent, these reduce, or, on contrary, promote the tolerance of cultural and religious diversity. This objective is delineated in three lines of research: the first is to construct a measure of beliefs concerning laïcité taking into account the different interpretations of laïcité expressed in the public debate; the second is to study, to what extent, adhesion to the dimensions of laïcité is related to more or less tolerance of cultural diversity; the third is to study, to what extent, adhesion to the dimensions of laïcité reduces, or, on the contrary, promotes tolerance of religious diversity. In conclusion, this thesis shows that different conceptions of laïcité exist. These either promote tolerance of cultural and religious diversity, or on the contrary, reduce tolerance of cultural and religious diversity. The contributions of this work, both at the level of academic research, and at the societal level are discussed in the general conclusion