The purpose of this study was to explore the relationships between process aspects of adolescent career development and the dynamic, family dimensions of adaptability and cohesion. Drawing from Super’s career development model, Tiedeman and O’Hara’s vocational decision-making model, Haren’s career decision-making paradigm and Olson et al’s. Circumplex Model of Marriage and Family Systems, curvilinear relationships were predicted between career development process variables and family adaptability-family cohesion. Adolescents in the study sample were 262 volunteer, high school seniors enrolled in three high schools (a rural, an urban, and a suburban) located in Southwest Virginia. Three summary hypotheses were tested by applying multiple regression analysis procedures. In the regression models examined, the criterion career development variables included: career decision-making style, occupational commitment, career planning, career exploration, decision-making and world-of-work information. The predictor variables consisted of family adaptability, family cohesion and related subdimension variables. The Assessment of Career Decision-Making and The Career Development Inventory were used to measure the criterion variables while the predictor variables were measured by the Family Adaptability and Cohesion Evaluation Scales. Hypothesis testing produced the following essential outcomes: (1) Six significant regression coefficients, distributed through four regression models, indicated that higher family adaptability (change) tendencies were associated with higher intuitive decision-making style levels, lower decision-making knowledge attained, adn lower world-of-work information acquired; whereas higher family cohesion (closeness) was related to more favorable career planning attitudes and higher measured levels of decision-making and world-of-work knowledge; (2) For the total sample, only the decision-making and world-of-work knowledge scales of the CDI were found to be significantly related to both family adaptability and family cohesion collectively; (3) a basic tenet of the Circumplex Model was challenged as no regression models examined yielded significant curvilinear relationships between the criterion and predictor variables; (4) The major dimensions of the Circumplex Model, family adaptability and cohesion were found to be correlated measures, a finding which also contradicted the Circumplex Model; and (5) Supplementary results provided partial explanations for some of the essential findings as well as supporting previous findings reported in the literature. / Ed. D.

The purpose of this study was to determine how word processing is being utilized in businesses with word processing systems in the Richmond metropolitan area. No data are available about the current implementation of word processing in a major metropolitan area in Virginia. This study was undertaken in order to add to the knowledge base that already exists about the implementation of word processing in other areas. Fifty word processing managers and supervisors representing the Word Processing Association of Richmond, with members from the metropolitan area, comprised the study population. The study addressed the following research questions: 1. How is the word processing concept being implemented in businesses with word processing systems in the Richmond metropolitan area? 2. What employment patterns exist in businesses with word processing systems in the Richmond Metropolitan area? 3. What plans do businesses with word processing systems in the Richmond Metropolitan area, have for expansion of the word processing system and for the application· of emerging technologies? A nine-part instrument was used to collect the data for the study. The instrument was validated by a panel of experts and was pretested before the data were collected. The Richmond metropolitan area was selected as the survey site because it contains a high concentration of organizations that are likely to benefit from the implementation of word processing. The Word Processing Association of Richmond was selected as the survey population because this group is representative of organizations utilizing word processing in the area. The researcher conducted fifty personal interviews between May and June, 1981. The major findings of this study follow: 1. The word processing employment market is expanding. Organizations are acquiring additional equipment, are planning to support more principals, and are creating additional positions for word processing personnel. 2. Word processing systems are generally centralized, are responsible for all correspondence tasks, operate in a modular office layout, and are managed by both a word processing manager and a supervisor. 3. Although the documents most frequently processed are memos/ letters, other applications are also being processed; statistical, medical, legal, and textual documents; address lists; and forms design and completion. 4. Longhand, machine dictation, typed drafts, and optical character recognition are used as sources of input in word processing. The use of each input mode varies with the type of document and the organizational preference. 5. The CRT display system is the most frequently used type of equipment and projections indicate that it will be the most frequently used type of equipment in five years. Blind standalones, online display systems, shared-logic systems, and photocomposition systems are also in use. 6. Emerging office systems technologies are in use and their use will expand. The integration of word processing and data processing will increase. The use of shared-logic, intelligent copiers, electronic mail, desk-top terminals for principals, OCR, micrographics, and telecommunication will increase. / Ed. D.

Sulfonated polysulfone has been shown to possess desirable physical properties for use as a reverse osmosis desalination membrane. In this work, an extensive of dense membranes made from sulfonated polysulfone having 0.2, 0.4, 0.5, 0.6, 0.8, and 1.0 degree of sulfonation is described. The degree of sulfonation (D.S.) was maintained during the membrane fabrication process as evidenced by IR analysis. The effect of the degree of sulfonation and the counter ion, namely Na and K, on the properties of the membrane were examined. The hydrophilic nature of the material increased with increasing degrees of sulfonation, as evidenced by water uptake and the contact angle of water on the membrane surface. The amount of water increased from 0.6% for polysulfone to 19.2% for sodium salt of sulfonated polysulfone with D.S. of 1.0, and 12.2% for potassium salt of sulfonated polysulfone with D.S. of 1.0. The contact angle of water on polysulfone membranes was 75.1°. The contact angle of water decreased to 25.5° and 60.3° for sodium and potassium salt of sulfonated D.S. = 1.0) polysulfone, respectively. The decrease in the contact angle of water indicated an increase in the hydrophilicity of the membrane surface. Both the water uptake study and the contact angle measurement indicated greater hydrophilicity for the sodium salts of sulfonated polysulfone when compared to the potassium salts of sulfonated polysulfone for a given degree of sulfonation. The nature of the water within the membrane was found to be less hydrogen-bonded when compared to the bulk water. The surface of the membrane and the polymer powder was found to be different by ESCA analysis, and were also different from the bulk of the material. Neither the membrane surface nor the polytner powder surface had the same stoichiometry as the bulk. Ion exchange occurred not only on the membrane surface, but extended into the bulk with an overall ion exchange of about 80%. Electrical properti.es of the membranes were investigated by measuring the partial ionic conductivity and the selectivity of the membrane. The electrolyte/membrane/ electrolyte system showed ohmic behaviour. The membrane potential difference under applied transient current was greatly dependent on the nature of the cation, whereas the nature of the anion had no effect. The activation energy had minimal dependence on the membrane thickness, but depended on the nature of the electrolyte system. The effective size of the ion-conducting channels seemed to increase with higher degrees of sulfonation, probably due to a swelling process. SEM photomicrographs were taken to study membrane morphology and, in some cases, performance as a reverse osmosis membrane could be predicted from the SEM photomicrographs . / Ph. D.

A five point radial response surface design supplemented with a control group and several single factor points was utilized to investigate the effects of sodium bicarbonate and disodium phosphate on animal performance, ruminal fermentation, ration digestibility and rate of passage of liquid and particulate phases of digesta. Rations contained 0 to 4.5% sodium bicarbonate and 0 to 2.5% disodium phosphate.. Calves were randomly assigned to experimental rations, eight to the control group, six to the centerpoint, two to the radial points and three to the single factor points with restrictions as to time. Animals were on a growth trial from wk 7 to 14. Human samples were taken for determination of pH, buffering capacity, volatile fatty acids anct ruminal ammonia and blood samples for determination of glucose and plasma urea nitrogen at 8, 11 and 14 wk. Rate of passage was determined using ytterbium and cobalt EDTA to follow the particulate and liquid phases of digesta respectively. A digestion trial was carried out concurrently with rate of passage determinations. A two compartment model and a gamma time-dependent model were fitted to marker excretion data. Average daily gains were not significantly affected by buffer additions, but appeared to be maxillial at 1 to 2% sodium bicarbonate and 0% disodium phosphate. Average daily gain and feed efficiency were not changed. Buffers consistently elevated total concentration of volatile fatty acids and osmolality in the rumen. Proportion of volatile fatty acids and acetate to propionate ratio were not changed by buffer addition. Digestibility of dry matter, organic matter, neutral detergent fiber, starch and acid detergent fiber are unchanged. Sodium bicarbonate increased ash digestibility while disodium phosphate tended to decrease ash digestibility. Urine volume and pH were increased by both buffers. Rumen dilution rate for liquid digesta was increased by 50% and particulate digesta increased by 25% with addition of buffers. Flow of liquid digesta was best described by a two compartment model and particulate digesta by a gamma time-dependent model. No benefit of manipulating rate of passage in young dairy calves was observed in this study. Manipulation of ruminal fermentation by rate ot passage has potential to increase; milk production by bypassing starch and protein. Rates of flow of particulate digest may exert important affects on the ruminal acetate to propionate ratio and has potential to explain milk fat depression. / Ph. D.

The purpose of this research was to characterize the phosphorus nutrition of Ilex crenata 'Helleri' and pine bark P relationships. Branched liners of 'Helleri' holly were grown in a pine bark medium in which 0, 5, 10, 15, 20, 25, or 30 ppm P were maintained. Shoot dry weight increased as the pine bark P level increased to 10 ppm P, while root dry weight decreased with increasing pine bark P levels. Total mg of P in shoot tissues continued to increase with P treatments higher than 10 ppm, indicating luxury consumption of P. Total mg of P in root tissues increased to the 10 ppm P treatment. Total µg of Fe, Cu, and Zn in shoot tissues followed the dry weight response, increasing to the 5-10 ppm P treatment then tending to decrease as pine bark P levels increased. Root tissue Fe was erratic while Cu did not vary with treatment and Zn decreased with increasing pine bark P levels. Total µg of Mn in shoot tissues increased with P treatments while total µg of Mn in root tissues decreased with increasing pine bark P levels. Dry shoot weights of 'Helleri' holly grown in a pine bark medium amended with either 270, 540, or 810 g/m³ of P or fertilized with 10 ppm P were not different while root dry weights decreased with increasing pine bark P levels. Water extractable P for the 810 g/m³ treatment decreased 245 ppm during the experiment and by week 5 was below 10 ppm. Amending the pine bark medium with 270 g/m³ of P did not increase the dry shoot weight of ‘Helleri’ holly when subsequently fertilized with a complete slow-release granular or water soluble fertilizer. The pine bark medium contained indigenous P which leached rapidly. When ‘Helleri’ holly were fertilized with a nutrient solution without P, 0.08 mg of indigenous P were absorbed. The pine bark adsorbed 7.5 µg of P per g of pine bark when equilibrated with a 10 ppm P nutrient solution. These studies indicate that maintaining 10 ppm P in the pine bark medium results in the greatest dry weight of 'Helleri' holly. A stable pine bark P level was not attained with superphosphate-amended pine bark, thus superphosphate is not recommended as a P source. Pine bark P relationships revealed that ‘Helleri’ holly absorbed indigenous P while a negligible amount of P was bound by the pine bark compared to the amount of P used by a ‘Helleri’ holly grown in a 1 liter container. / Ph. D.

Two Virginia isolates of soybean mosaic virus (SHV), VA and OCM, were classified as G1 and G3 strains, respectively, according to a soybean differential cultivar system. G1/VA and G3/OCM differed in the symptom severity induced on soybean (Glycine max [L.]Merr.) plants and by the production by G3/OCM of cytoplasmic strands, containing virus particles, within infected leaf cells. Two Illinois isolates, G1/IL and G3/IL, resembled G3/0CM in mild symptoms; induced in soybean plants and by the production of cytoplasmic strands ultrastructurally. G1/VA differed from the 3 mild strains by the severe symptoms induced on plants and by the absence of cytoplasmic strands ultrastructurally. All 4 strains were closely related serologically. The tolerant reaction of soybean to the 3 mild SMV strains was correlated with production of cytoplasmic strands. Soybean plants were most susceptible to G1/VA and peanut stunt virus (PSV) when the primary leaves were inoculated at 50-75% of their full expansion. Plants developed more severe symptoms with either virus within a shorter incubation period than did plants which were inoculated when their primary leaves were less than or greater than 50-75% expansion. The SMV strain, SMV-VA (G1/VA), was used to determine the cell types SMV moves into, using pinwheel inclusions as indicators of cell infection, at an early stage of infection when virus particles were first detectable in inoculated and noninoculated tissues of prilutry leaves. By using serologically specific electron microscopy (SSEM), virus particles were first detected in inoculated tissues at 6 days after inoculation. Pinwheels were detected within these areas in palisade, paraveinal, spongy, vascular parenchyma, phloem and immature xylem cells. The pinwheels were frequently opposed to the plasmalemma and were associated with plasmodesmata and plasmalemmasomes. Endoplasmic reticulum was associated with the base of those pinwheels found in the cytoplasm. The early stage of SMV pinwheel formation appeared to be similar to that reported for other potyviruses. The observation of pinwheels in the paraveineal mesophyll cells suggested the involvement of these cells in virus translocation within the soybean leaf. A sinusoidal pattern of SMV particle concentration within the inoculated and noninoculated areas of the leaf was detected by SSEM. The appearance of necrotic lesions within the inoculated area was correlated with an increase in the number of detectable particles within the area. A similar correlation was made with an increase in particle numbers in the non-inoculated area and the appearance of vein-clearing on the first trifoliolate leaf. It was also noted that particle numbers increased in the midrib and petiole when particle numbers decreased in the inoculated and noninoculated areas. This pattern was hypothesized to be due to either an alteration in the viral replication rate or to translocation relationships within the leaf. / Ph. D.

The western boundary of the Charlotte Belt near Brookneal, Virginia lies midway along a 100 km length of the boundary previously mapped by reconnaissance methods only (Jonas, 1928). This study concludes that the metavolcanic Chopawamsic Formation of northern and central Virginia is the extension of the Charlotte Belt. The Charlotte Belt is bounded to the west by the metasedimentary Evington Group that extends from northern Virginia southward into the Smith River Allochthon as the Fork Mountain Schist. In Brookneal, the boundary between the eastern metavolcanic and western metasedimentary units is obscured by the intrusion of the 470 Ma Melrose Granite. The abrupt change in lithology and multiple fault generation across the granite indicates that the boundary between the metasedimentary and metavolcanic units is tectonic. Unconformably overlying both the metavolcanic and metasedimentary units is the Arvonia sequence, previously not documented in the southern Virginia Piedmont. The Brookneal terrane has undergone three metamorphic events and localized hydrothermal retrogression. The metamorphism is tied in sequence to seven folding episodes. The metamorphism and deformation are results of the regional Taconic event, the late-Acadian event which terminates to the west in Brookneal, and the fault localized Alleghanian event, each of which resulted in faulting. / Master of Science

Dans la présente étude, nous avons étudié les caractéristiques physiques et anatomiques du bois de peuplier deltoïde afin de pouvoir bâtir une sélection sur des données quantitatives en vue d'une amélioration de cette espèce. Le matériel, des carottes de 5,0 mm de diamètre prises à une hauteur de 0,4 m du sol, provenant du populetum de Villeroy (Québec), était âgé de dix ans. La densité basale, la longueur des fibres et l'analyse de tissu ont été choisies comme paramètres importants, soit pour approfondir les connaissances de cette espèce, soit pour effectuer une sélection efficace. Pour mieux comprendre l'interdépendance de ces paramètres, on les a reliés à des données auxométriques, tels le taux de croissance annuelle, la largeur du dernier cerne formé, la hauteur des arbres et la coloration ou pourriture du bois de coeur. La densité basale du peuplier deltoïde (353,4 kg/m³) se trouve être inférieure à celle du peuplier faux-tremble. Celui-ci étant en forêt naturelle le peuplier le plus utilisé au Québec, pourrait donc être partiellement substitué par le deltoïde en plantation. L'héritabilité au sens strict de ce caractère (97,33% à l'âge de huit ans) permet une sélection efficace des arbres ou familles intéressantes et garantit la stabilité des descendants pour ce paramètre. Une relation entre la densité basale et les conditions de croissance n'a pas pu être trouvée pour l'espèce en question. Ainsi, ce paramètre n'est ni fonction de la largeur des cernes ni fonction du taux de croissance annuelle, mais en relation directe avec l'épaisseur de la paroi secondaire des fibres. La longueur des fibres du peuplier deltoïde (0,956 mm) est légèrement inférieure à celle des autres espèces nord-américaines de peuplier. Il est cependant possible de l'augmenter en sélectionnant les arbres, dont la longueur se situe au-dessus de la moyenne, puisque ce caractère lui aussi est sous contrôle génétique. La longueur des fibres n'est pas fonction du taux de croissance radiale et n'a pas de relation avec les conditions de croissance. La longueur maximale étant atteinte à environ dix ans, ceci présume une montée très rapide pendant les premières années de croissance. L'espèce étudiée possède une surface moyenne occupée par les fibres de 66,53%. Ce paramètre est inversement proportionnel à la proportion de surface occupée par les vaisseaux. Il semble être influencé par les conditions de croissance, d'autant plus que la mise en place des vaisseaux est fonction de l'ampleur de la couronne de l'arbre. L'analyse des résultats nous a démontré que le pourcentage des fibres augmente avec la largeur du cerne. On peut donc conclure qu'en améliorant les conditions de croissance, on obtiendra automatiquement un pourcentage supérieur de fibres. Cette étude qui a été effectuée dans le but d'acquérir des connaissances sur la qualité du bois de peuplier deltoïde, met à la disposition du sélectionneur non seulement des données générales, mais aussi toute une série de corrélations, de régressions et de calculs d'héritabilité permettant une sélection efficace.

L'objectif principal de cet ouvrage fut d'établir et de comparer les possibilités d'isolation thermique des constructions industrialisées en bois, tout en satisfaisant aux exigences en vigueur. La conductivité thermique permet de quantifier la déperdition de chaleur à travers un matériau ou un élément, mais on préfère utiliser son inverse, la résistance thermique, pour caractériser le pouvoir isolant. Cette résistance thermique est très dépendante de la présence d'eau dans la paroi; il est nécessaire de pouvoir détecter et mesurer l'humidité afin de contrôler, d'autre part, la condensation. L'application de ces concepts aux bâtiments en bois constitue la phase pratique du présent travail. Il présente des solutions d'isolation thermique des différentes parties de la maison en fonction, entre autres, de la nature et de l'épaisseur de l'isolant. Ce présent travail peut constituer un guide pratique pour les professionnels du bâtiment, afin de choisir et de concevoir un modèle d'isolation conforme aux normes.

« Au cours de la dernière décennie, la recherche en marketing a profondément mis l'accent sur le développement d'un corps théorique de connaissances du processus de traitement humain de l'information. Un tel effort mérite beaucoup d'égards, car la compréhension du processus de traitement de l'information par le consommateur procurera d'importants éclaircissements sur les mécanismes perceptuels et cognitifs, composantes cruciales des modèles de comportement. Basée sur la notion de système de traitement humain de l'information de Newell et Simon (1972, p. 20-21) dont l'approche micro précisait trois composantes essentielles: 1) une mémoire composée de structures de symboles; 2) un ensemble de programmes et de processus d'information élémentaires qui peuvent manipuler les structures de symboles; 3) et des mécanismes d'interaction avec l'environnement, la présente thèse tente principalement d'expliquer l'écart existant entre le message en provenance d'un stimulus externe et l'information retenue (perçue et comprise) par les consommateurs. Dans le cœur du débat sur la plus ou moins grande quantité d'information utile au preneur de décision dont Jacoby et ses collaborateurs sont les principaux instigateurs de recherche, notre travail vise également à éclaircir certains résultats de recherche plus ou moins validés dont la notion de charge d'information et le comportement perceptuel des individus. Pour ce faire, nous avons sélectionné au hasard 150 consommatrices (dont 130 cas furent traités) auxquelles nous avons demandé d'observer cinq boîtes de conserves sur lesquelles nous avions collé des nouvelles étiquettes impliquant une quantité maximale d'information fournie de cinq 'bits". Utilisant un "plan d'expérience" factoriel 5 x 5 (5 niveaux d'information et 5 séries d'étiquettes), nous avons mesuré trois ensembles d'hypothèses: le premier se rapportant à la relation entre la quantité d'information fournie et la quantité d'information retenue (perçue et comprise); le deuxième traitant de l'impact du temps d'observation sur la quantité d'information retenue; et le troisième visant l'explication de la quantité d'information retenue à partir des variables socio-économiques (revenu, âge, scolarité) et psychologiques (personnalité, quotient intellectuel et styles cognitifs). La recherche s'est déroulée en deux étapes impliquant trois périodes de mesure. En effet, les consommatrices interviewées devaient se présenter pour deux entrevues dans un laboratoire à l'Université Laval à une fréquence de 15 jours d'intervalle. Lors de la première rencontre, une première mesure de la quantité d'information retenue et des variables socio-économiques et psychologiques avait lieu. Puis, au bout de 15 jours, une deuxième entrevue s'effectuait avec deux mesures de la quantité d'information retenue; l'une avant l'observation des étiquettes (les mêmes qu'au cours de la première rencontre) et l'autre immédiatement après. D'un tel protocole expérimental, et après utilisation de la régression comme technique d'analyse, nous avons obtenu les résultats suivants: La relation curviligne entre la quantité de données à traiter et la quantité d'information retenue n'est pas confirmée. Le transfert de l'information de la mémoire à court terme à la mémoire à long terme est influencé par le style cognitif du traiteur et la capacité de traitement initial de la mémoire à court terme. Plus un individu est perceptif, plus on lui fournit de l'information à traiter, moins il oublie d'information. Le gain d'information acquis par l'apprentissage et/ou suite à une deuxième exposition à l'information fournie n'est pas en relation linéaire avec le niveau d'information donnée. Il existe une relation linéaire entre le temps d'observation des stimuli et la quantité d'information retenue pour chaque période d'observation. Le style cognitif n'intervient pas comme une variable explicative significative de la relation entre la quantité d'information fournie et les informations mal retenues. Les résultats des modèles de régression montrent que les dominances cognitives ne sont pas des variables explicatives de la quantité d'information retenue. L'âge est inversement relié à la quantité d'information retenue, le quotient intellectuel est directement relié à cette variable, alors que le niveau de scolarité en interaction avec la quantité d'information fournie est directement relié à la quantité d'information retenue (après la deuxième période d'observation seulement). Le revenu n'est pas une variable explicative significative du traitement initial de l'information. Il en est de même pour la complaisance et l'agressivité. Par contre, le détachement intervient de façon négative dans l'explication de la quantité d'information retenue après la deuxième rencontre seulement. L'apport managérial d'une telle recherche se solde par l'idée de présenter aux consommateurs une information pré-traitée. Dans le cadre d'une politique nutritionnelle globale pour le Québec, une telle innovation faciliterait grandement l'application du concept de nutrition balancée. Parmi les autres contributions de cette thèse, nous notons l'identification de plusieurs projets de recherche portant sur les styles cognitifs et la personnalité entre autres. »--Pages xii-xiv