IMPACTS OF PRICE VARIABILITY ON MARKETING MARGINS AND PRODUCER VIABILITY IN THE TEXAS WHEAT INDUSTRY

The effects on marketing margins and Texas what producers of shifting from a period with stable prices to a period without stable prices were investigated using both econometric and simulation techniques. Empirical evidence reveals wheat export firms are risk averse and that either futures markets were unable to absorb increased price risk or futures markets absorbed increased price risk at a cost of $0.054 per bushel. Increased variability in prices and reduced farm program benefits substantially reduced the probability of Texas wheat producers receiving a reasonable return on equity and a reasonable rate of asset accumulation.Crop Production/Industries, Marketing,

The Relationship between Marital Status and Psychological Resilience in Chronic Pain

We examined the relationship between marital status and a 2-stage model of pain-related effect, consisting of pain unpleasantness and suffering. We studied 1914 chronic pain patients using multivariate analysis of covariance (MANCOVA) to clarify whether marital status was a determinant factor in the emotional or ideational suffering associated with chronic pain after controlling for pain sensation intensity, age, and ethnicity. Marital status was unrelated to immediate unpleasantness (). We found a strong association with emotional suffering () but not with negative illness beliefs (). Interestingly, widowed subjects experienced significantly less frustration, fear, and anger than all other groups (married, divorced, separated, or single). A final MANCOVA including sex as a covariate revealed that the emotional response to pain was the same for both widow and widower. Only those individuals whose spouse died experienced less emotional turmoil in the face of a condition threatening their lifestyle. These data suggest that after experiencing the death of a spouse, an individual may derive some “emotional inoculation” against future lifestyle threat

Dynamic Modeling of the Product Life Cycle in the Commercial Mainframe Computer Market, 1968-1982

This research investigates product life cycles in the commercial mainframe computer market. We show that empirical studies conducted at the product level are useful for investigating processes underlying product life cycles. We use hazard models with time-varying covariates to estimate the probability of product exit and Poisson models to estimate the probability of introduction. We measure the importance of different aspects of market structure, such as the degree of competitiveness, cannibalization, vintage, product niche and firm effects. We find some evidence of a relationship between the determinants of product exit and product entry.

Lateral cephalometric analysis of asymptomatic volunteers and symptomatic patients with and without bilateral temporomandibular joint disk displacement

Few studies of dentofacial and orthodontic structural relationships relative to temporomandibular joint (TMJ) dysfunction have been reported. We undertook this investigation to determine any correlation of orthodontic and dentofacial characteristics with TMJ bilateral disc displacement. The population of patients was selected from a TMJ clinic where a control group of asymptomatic volunteers had been previously established and standardized. Differences in skeletal structural features were determined among three study groups: (1) asymptomatic volunteers with no TMJ disk displacement, (2) symptomatic patients with no TMJ disc displacement, and (3) symptomatic patients with bilateral TMJ disk displacement. Thirty-two asymptomatic volunteers without disk displacement (25 female, 7 male) were compared with the same number each of symptomatic patients without TMJ disk displacement and symptomatic patients with bilateral TMJ disk displacement. All subjects had undergone a standardized clinical examination, bilateral TMJ magnetic resonance imaging, and lateral cephalometric radiographic analysis. The groups were matched according to sex, TMJ status, age, and Angle classification of malocclusion. Seventeen lateral cephalometric radiographic cranial base, maxillomandibular, and vertical dimension variables were evaluated and compared among the study groups. The mean angle of SNB, or the intersection of the sella-nasion plane and the nasion–point B line (indicating mandibular retrognathism relative to cranial base), of the symptomatic patients-with-displacement group was significantly smaller than that in the asymptomatic volunteers and symptomatic patients without bilateral disk displacement (p \u3c 0.05). Female subjects showed smaller linear measurements of mandibular length, lower facial height, and total anterior facial height than male subjects in all three groups (p \u3c 0.05). The mean angle of ANB, or the intersection of the nasion–point A and nasion–point B planes (indicating retrognathism of mandible relative to maxilla), was significantly greater in female than in male subjects, in all groups (p \u3c 0.05). Symptomatic patients with bilateral disk displacement had a retropositioned mandible, indicated by a smaller mean SNB angle compared with that in asymptomatic volunteers and symptomatic patients with no disk displacement on either side. Lateral cephalometric radiographic assessment may improve predictability of TMJ disk displacement in orthodontic patients but is not diagnostic; nor does the assessment explain any cause-and-effect relationship. (Am J Orthod Dentofacial Orthop 1998;114:248-55.

Morphologic alterations in the rat medullary collecting duct following potassium depletion

Morphologic alterations in the rat medullary collecting duct following potassium depletion. Freeze-fracture and thin-section electron microscopy and morphometry were used to characterize further the response of the rat medullary collecting duct to potassium depletion. In freeze-fracture replicas, principal cells and intercalated cells were identified based on the assumption that intercalated cells possess a high density of rod-shaped intra-membrane particles in their luminal membranes. Potassium depletion caused an increase in the relative number of cells with a high density of rod-shaped particles from the control level of 22% to 31% after 2 weeks and to 36% after 4 weeks. The frequency of intercalated cells identified by thin-section criteria was, however, about 35% in controls and unchanged by potassium depletion. This suggests that intercalated cells can have two types of membrane morphology. In potassium depletion, all intercalated cells display a high density of rod-shaped particles in their luminal membranes. In addition, the luminal membrane area of intercalated cells increased more than threefold, and the density of their rod-shaped particles increased by 21%. These observations suggest that the intercalated cell and its rod-shaped particle may be involved with the potassium reabsorption that occurs in this nephron segment with potassium depletion.Modifications morphologiques du canal collecteur du rat consécutives à une depletion en potassium. Le cryo-décapage, la microscopie électronique sur coupes fines et la morphométrie ont été utilisés pour mieux établir la réponse du canal collecteur médullaire du rat à la depletion en potassium. Sur les répliques de cryo-décapage les cellules principales et les cellules intercalaires ont été identifiées à partir de l'hypothèse selon laquelle les cellules intercalaires possèdent une grande densité de particules intra-membranaires luminales en forme de batonnets. La depletion en potassium a déterminé une augmentation du nombre relatif de cellules de ce type de 22% chez les témoins à 33% après 2 semaines et 36% après 4 semaines. La fréquence des cellules intercalaires identifiées sur coupes minces, cependant, était de 35% chez les contrôles et non modifiés par la depletion en potassium. Cela suggère que les cellules intercalaires peuvent avoir deux types de morphologies membranaires. Dans la depletion en potassium toutes les cellules intercalaires ont une grande densité de particules en forme de batonnets dans leurs membranes luminales. De plus, la surface membranaire luminale des cellules intercalaires augmente de plus de trois fois et la densité des particules augmente de 21%. Ces observations suggèrent que les cellules intercalaires et leurs particules en forme de batonnets peuvent être impliquées dans la réabsorption de potassium qui prend place dans ce segment du néphron au cours de la déplétion en potassium

Determining Optimal Levels of Nitrogen Fertilizer Using Random Parameter Models

The parameters of yield response functions can vary by year. Past studies usually assume yield functions are nstochastic ‘‘limited’’ stochastic. In this study, we estimate rye– ryegrass yield functions in which all parameters are random. The three functional forms considered are the linear response plateau, the quadratic, and the Spillman-Mitscherlich. Nonstochastic yield models are rejected in favor of stochastic parameter models. Quadratic functional forms fit the data poorly. Optimal nitrogen application recommendations are calculated for the linear response plateau and Spillman-Mitscherlich. The stochastic models lead to smaller recommended levels of nitrogen, but the economic benefits of using fully stochastic crop yield functions are small because expected profit functions are relatively flat for the stochastic yield functions. Stochastic crop yield functions provide a way of incorporating production, uncertainty into input decisions.cereal rye–ryegrass, Monte Carlo, nitrogen, random parameters, stochastic plateau, Production Economics, Q10, C12, D24,

Determining Optimal Levels of Nitrogen Fertilizer Using Random Parameter Models

The parameters of yield response functions can vary by year. Past studies usually assume yield functions are nonstochastic or ‘limited’ stochastic. In this study, we estimate rye-ryegrass yield functions where all parameters are random. Optimal nitrogen rates are calculated for two yield response functions: linear response plateau and quadratic. Nonstochastic models are rejected in favor of stochastic parameter models. However, the economic benefits of using fully stochastic models are small since optimal nitrogen rates do not differ greatly between stochastic and nonstochastic models.Linear response plateau, Monte Carlo, nitrogen, random parameters, Agricultural and Food Policy, Crop Production/Industries, Farm Management, Production Economics,

Dating Around: Investigating Gender Differences in First Date Behavior Using Self‐Report and Content Analyses from Netflix

In the current studies, we used qualitative, quantitative, and content analysis to understand which frst date behaviors individuals perceive as critical for landing second dates. In Study 1 (N=100), men and women reported tactics or behaviors that they believed someone of their gender would perform on a successful frst date. We observed that men and women perceive similar behaviors as important to engage in on successful frst dates. Study 2 (N=131) had men and women rate the perceived efectiveness of these tactics. When the behaviors are aggregated, men perceive women who engage in “Involvement” behaviors as better at obtaining sec- ond dates. In contrast, women perceive men who engage in “Etiquette” behaviors as more likely to land second dates. In Study 3, we coded the Netfix show, Dat- ing Around, using the tactics from Study 1 to examine if engaging in these tactics more frequently predicted having a successful date. Results revealed that receiving a second date was not related to an individual’s engagement in these tactics. This research is the frst to attempt to empirically delineate tactics that occur on frst dates and lead to second dates for men and women