Acid-base titrations for polyacids: Significance of the pK sub a and parameters in the Kern equation

A new method is suggested for calculating the dissociation constants of polyvalent acids, especially polymeric acids. In qualitative form the most significant characteristics of the titration curves are demonstrated and identified which are obtained when titrating the solutions of such acids with a standard base potentiometrically

Mechanism controlling the initiation of lactation at parturition.

Publication authorized May 11, 1948.Digitized 2007 AES.Includes bibliographical references (pages 54-65)

Normal maintenance and experimental inhibition and augmentation of lactation.

Publication authorized May 11, 1948.Digitized 2007 AES.Includes bibliographical references (pages 32-36)

Enhanced Negative Feedback Responses in Remitted Depression

Major depressive disorder (MDD)is characterized by hypersensitivity to negative feedback that might involve frontocingulate dysfunction. MDD patients exhibit enhanced electrophysiological responses to negative internal (errors) and external (feedback) cues. Whether this dysfunction extends to remitted depressed (RD) individuals with a history of MDD is currently unknown. To address this issue, we examined the feedback-related negativity in RD and control participants using a probabilistic punishment learning task. Despite equivalent behavioral performance, RD participants showed larger feedback-related negativities to negative feedback relative to controls; group differences remained after accounting for residual anxiety and depressive symptoms. The present findings suggest that abnormal responses to negative feedback extend to samples at increased risk for depressive episodes in the absence of current symptoms.Psycholog

Implicit Depression and Hopelessness in Remitted Depressed Individuals

Cognitive theories of depression posit that automatically activated cognitive schemas, including negative thoughts about the self and the future, predispose individuals to develop depressive disorders. However, prior research has largely examined these constructs using explicit tests in currently depressed individuals. Using the Implicit Association Test (IAT), the present study examined automatic associations between the self and mood state ("depression IAT") and between the future and mood state ("hopelessness IAT") before and after a negative mood induction in 19 remitted depressed individuals and 23 healthy controls. In the depression IAT, remitted depressed participants exhibited an overall lower tendency to associate themselves with happiness relative to the healthy controls before the mood induction. Control, but not remitted depressed, participants' automatic associations between the self and happiness diminished following the mood induction. Contrary to our hypotheses, no significant findings emerged when considering the hopelessness IAT. Consistent with prior studies, no significant correlations emerged between implicit and explicit biases, suggesting that these measures probe different processes. Results extend prior IAT research by documenting the presence of a reduced tendency to associate the self with happiness in a sample at increased risk for depression.Psycholog

THE THOUGHTS WITHIN: COGNITIVE STYLES AS MEDIATORS BETWEEN PERCEIVED PARENTING AND SYMPTOMS OF DEPRESSION AND ANXIETY

Given the high degree of comorbidity between depression and anxiety and their impact on quality of life, knowledge of shared and unique factors implicated in their development is critical. Although research has linked parenting behaviors and negative schemas with their development, little is known about how specific parenting behaviors affect schema development. The present study explored the relation between perceived parenting, dysfunctional attitudes about the self and anxiety, and aspects of affective symptomatology. Lower levels of parental care were associated with both dysfunctional attitudes and anxiety sensitivity, and parental overprotection was specifically associated with negative beliefs about anxiety. Although dysfunctional attitudes uniquely predicted symptoms of depression, beliefs about anxiety were nonspecific predictors of affective symptomatology. The present findings provide support for assessing specific elements of parenting, cognitive styles, and affective symptomatology independently. Implications for understanding the development of affective disorders and identification of targets for preventive and treatment interventions are discussed