The Relationship of Social Support to African American Caregivers' Help-Seeking for Emotional Problems

This study analyzes whether social support serves as a link to or substitute for formal services among African American female caregivers seeking help with emotional problems. It also analyzes other determinants of help-seeking. It relies on data from the Black Rural and Urban Caregivers Mental Health and Functioning Study and is guided by a modified version of the behavioral model of health services use. Using hierarchical binary logistic regression, analyses reveal that only age, stress, and support from fellow church members are statistically significantly associated with the likelihood of help-seeking. These results support the linking hypothesis, suggesting that the social support received by African American women caregivers in the context of their religious organizations helps to link them to services.     

Seasonality and vertical structure of light-attracted insect communities in a dipterocarp forest in Sarawak

Nocturnal flying insects were collected monthly for 13 months using ultra violet light-traps set at various vertical levels in a weakly-seasonal, tropical lowland dipterocarp forest in Sarawak, Malaysia. Abundance, faunal composition, size distribution and guild structure of these samples were analyzed with respect to temperal and vertical distributions. The nocturnal flying insect community in the canopy level was highly dominated by fig wasps (84%) in individual number, and by scarabaeid beetles (28%) in weight. A principal component analysis on monthly catches detected non-random, seasonal trends of insect abundance. The first two principal trends were an alternation of wetter (September to January) and less wet seasons (February to August) and an alternation between the least wet (January to March) and the other seasons. Many insect groups were less abundant in the least wet season than the other seasons, whilst inverse patterns were found in Scarabaeidae and Tenebrionidae. Significantly positive and negative correlations between monthly catch and rainfall were detected only in ovule-feeders and in phloem-feeders, respectively. Delayed, significant negative correlations between monthly catch and 1–3 month preceding rainfall were more frequently detected in phytophages, phloem-feeders, seed-feeders, wood-borers and scavengers. The peak in abundance along vertical levels were found at the canopy level (35 m) for phloem-, ovule-, seed-, root-, fungal-feeders and nectar collectors, at an upper subcanopy level (25 m) for scavengers and aquatic predators, and at a middle subcanopy level (17 m) for ants. Catches at the emergent level (45 m) did not exceed those at the canopy level.     

Application of Human Reliability Analysis to Nursing Errors in Hospitals

Adverse events in hospitals, such as in surgery, anesthesia, radiology, intensive care, internal medicine, and pharmacy, are of worldwide concern and it is important, therefore, to learn from such incidents. There are currently no appropriate tools based on state-of-the art models available for the analysis of large bodies of medical incident reports. In this study, a new model was developed to facilitate medical error analysis in combination with quantitative risk assessment. This model enables detection of the organizational factors that underlie medical errors, and the expedition of decision making in terms of necessary action. Furthermore, it determines medical tasks as module practices and uses a unique coding system to describe incidents. This coding system has seven vectors for error classification: patient category, working shift, module practice, linkage chain (error type, direct threat, and indirect threat), medication, severity, and potential hazard. Such mathematical formulation permitted us to derive two parameters: error rates for module practices and weights for the aforementioned seven elements. The error rate of each module practice was calculated by dividing the annual number of incident reports of each module practice by the annual number of the corresponding module practice. The weight of a given element was calculated by the summation of incident report error rates for an element of interest. This model was applied specifically to nursing practices in six hospitals over a year; 5,339 incident reports with a total of 63,294,144 module practices conducted were analyzed. Quality assurance (QA) of our model was introduced by checking the records of quantities of practices and reproducibility of analysis of medical incident reports. For both items, QA guaranteed legitimacy of our model. Error rates for all module practices were approximately of the order 10(-4) in all hospitals. Three major organizational factors were found to underlie medical errors: "violation of rules" with a weight of 826 x 10(-4), "failure of labor management" with a weight of 661 x 10(-4), and "defects in the standardization of nursing practices" with a weight of 495 x 10(-4).     

Nectar secretion pattern of the dish-shaped flower,Cayratia japonica (Vitaceae), and nectar utilization patterns by insect visitors

Summary We studied the relationship between the diurnal nectar secretion pattern of flowers ofCayratia japonica and insect visiting patterns to these flowers. Flower morphology ofC. japonica changed greatly for about 12 hours after flower-opening and the maximum duration of nectar secretion was 2 days. The nectar volume peaked at 11∶00 and 15∶00, and declined at night and at 13∶00 regardless of time elapsed after flower-opening. The nectar volume at the two peaks was, on average, 0.25 μl on bagged inflorescences and 0.1μl on unbagged inflorescences (both, sugar concentration=60%). The flower secreted nectar compensatory when the nectar was removed. This means that insects consume more nectar than the difference of nectar volume between bagged and unbagged flowers. Apis cerana is a primary visitor of this flower, and was the only species for which we confirmed pollen on the body, among many species of flower visiting insects to this flower.Apis cerana visited intensively at the two peaks of nectar secretion. Visits of the other insects were rather constant or intensive only when there was no nectar secretion. Thus flowers ofC. japonica with morphologically unprotected nectaries may increase likelihood that their nectar is used by certain pollinators, by controlling the nectar secretion time in day. In this study the pattern of nectar secretion allowedA. cerana maximum harvest of nectar. Contribution to the ecological and bioeconomoical studies of the pollinator community in Kyoto I.     

On Efron's Parameterization

This paper discusses a curved exponential family of distributions which is defined by a differential equation with respect to the expectation parameters in the two–dimensional exponential family. The differential equation considered here is the same as the one given by Efron (1975) for the trinomial distribution. This equation is extended here to a general exponential family, and called Efron's parameterization in the two–dimensional exponential family. The solution of Efron's parameterization is obtained explicitly in an exponential family, although Kumagai & Inagaki (1996) showed that there exists no proper solution of Efron's equation for the trinomial distribution, in line with the counterexample given by Efron (1975 p. 1206). The paper gives some characterizations of Efron's parameterization with special reference to Fisher's circle model. The implications of these characterizations are the two–dimensional normal distribution and a spiral curve in the plane.     

Iterative weighted least-squares estimates in a heteroscedastic linear regression model

The aim of this study is to improve the efficiency of weighted least-squares estimates for a regression parameter. An iterative procedure, starting with an unbiased estimate other than the unweighted least-squares estimate, yields estimates which are asymptotically more efficient than the feasible generalized least-squares estimate when errors are spherically distributed. The result has an application in the improvement of the Graybill–Deal estimate of the common mean of several normal populations.     

A flexible two-dimensional mortality model for use in indirect estimation

Mortality estimates for many populations are derived using model life tables, which describe typical age patterns of human mortality. We propose a new system of model life tables as a means of improving the quality and transparency of such estimates. A flexible two-dimensional model was fitted to a collection of life tables from the Human Mortality Database. The model can be used to estimate full life tables given one or two pieces of information: child mortality only, or child and adult mortality. Using life tables from a variety of sources, we have compared the performance of new and old methods. The new model outperforms the Coale-Demeny and UN model life tables. Estimation errors are similar to those produced by the modified Brass logit procedure. The proposed model is better suited to the practical needs of mortality estimation, since both input parameters are continuous yet the second one is optional.