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• Pecan nut follows a simple sigmoid curve from fruit set until the harvest of the nut. • Gompertz model fit best for the embryo development whereas logistic model show high efficiency for shell. • Both logistic and gompertz model show high efficiency for the development of shuck. • Finding from research can guide in building an integrated growth model with three phenotypic traits (shuck, shell, and embryo). • Model can aid in orchard management practices like irrigation, thinning and pest management. Pecan is the only commercial tree nut native to the United States. The optimal times for orchard irrigation, pesticide sprays, and harvest are difficult to identify. Growth and development of the nut as a function of heat unit accumulation is a potential tool predicting different nut growth stages. Growth models utilizing heat unit accumulation are useful decision making tools for growers to fine tune inputs. The objective of this research was to compare different non-linear growth models and determine which best fits the growth and development of the pecan nut components i.e., embryo, shell, and shuck. The sampled nuts were collected in two different years (2019 and 2020). In 2019, three varieties of nuts were sampled from five different locations. In 2020, samples of two varieties were collected from one location. Separate models were fitted for (1) the 2019 data to capture the variation among different locations and varieties and (2) the 2019 and 2020 data within one location that also considered the random effect between years for the two cultivars. A comparison of the coefficient of determination (R2) and Akaike information criteria (AIC) among the fitted models, demonstrated the Gompertz model best fit the embryo development for both datasets. It also best described the shuck growth in the 2019 data. The Logistic model performed slightly better than Gompertz for modeling shell growth for both datasets and the shuck for the two-year data. In both years, slow initial growth of fruit was observed until the beginning of the water stage, followed by an increase in size until the gel stage through nut filling in the dough stage. Our findings suggest that irrigation is more crucial during the water stage of pecan, whereas thinning should be done at the late water stage prior to the nut filling stage. Similarly, pesticide use can be minimized by determining when the pecan shell lignifies and is not susceptible to piercing sucking insect mouthparts. These results can guide pecan growers in fine tuning irrigation, thinning, and pest management based on an integrated growth model of the three phenotypic traits, shuck, shell, and embryo, as a function of accumulated heat units. [ABSTRACT FROM AUTHOR]

This article provides an historical reflection on the central purpose of U.S. public diplomacy such national security instrument and demonstrates that U.S. public diplomacy has been principally an ad hoc instrument of American foreign policy to meet wartime exigencies and has been underscored by the promotion of American values of democracy and freedom. Over the years, it has expanded to encompass multiple modes of engagement, while at the same time there has been constant tension concerning the role of public diplomacy as a strategic, policy function versus merely as a "mouthpiece" within the foreign affairs apparatus. All of these themes continue to reverberate in the contemporary practice of American public diplomacy. [ABSTRACT FROM AUTHOR]

Objective: We sought to evaluate differences in the stage at diagnosis and the survival of breast cancer patients enrolled in two different Medicare healthcare delivery systems: fee for service (FFS) and health maintenance organizations (HMO). Methods: We used a linkage of two national databases, the Medicare database from the Centers for Medicare and Medicaid Services (CMS), and the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) program database, to evaluate differences in demographic data, stage at diagnosis, and survival in patients with breast cancers over the period 1985–2001. Results: Medicare patients enrolled in HMOs were diagnosed at an earlier stage of diagnosis than FFS patients. HMO patients diagnosed with breast cancer had improved survival, and these differences remained even after controlling for potential confounders. Specifically, breast cancer patients enrolled in HMOs had 9% increased probability of survival (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.88-0.93) than their counterparts enrolled in FFS. These findings persisted even when patients had a cancer diagnosis before their breast cancer. Conclusions: Improved survival among breast cancer patients in HMOs compared with FFS is likely due to a combination of factors, including but not limited to earlier stage at the time of diagnosis. [ABSTRACT FROM AUTHOR]

The article reports on results of a study of cutaneous soft tissue sarcoma (CSTS) incidence patterns in the United States. A description of the experimental set-up and measurement method is presented. The study concluded that CSTS rates varied markedly over time and by race, sex and histologic type which supported the notion that these histologic variants of CSTS are etiologically distinct.

Levels of three major dehydrins of 65, 60, and 14 kDa have been observed to increase in blueberry (Vaccinium spp.) floral buds during chill unit accumulation and cold acclimation and decrease during deacclimation and resumption of growth. Indeed, levels of the 65-, 60-, and 14-kDa dehydrins increase such that they become the most predominant proteins visible on sodium dodecyl sulfate (SDS)-polyacrylamide gels. The peptide sequence information from the 65- and 60-kDa dehydrins was used to synthesize degenerate DNA primers for amplification of a part of the gene(s) encoding the dehydrins. One pair of primers amplified a 174-bp fragment. The 174-bp fragment was used to screen a cDNA library (prepared from RNA from cold-acclimated blueberry floral buds) and resulted in the isolation of a clone with a 2.0-kb insert. The cDNA was sequenced and found to be a full-length clone encoding a K5-type dehydrin (5 K boxes). Five high-confidence peptide sequences, ranging from 9 to 25 amino acids long, obtained from the 60-kDa dehydrin exactly matched sequences encoded within the cDNA clone. Furthermore, amino acid composition of the 60-kDa dehydrin agreed well with the expected amino acid composition based on the cDNA sequence. However, the DNA sequence and coupled in vitro transcription/translation reactions of the cDNA clone indicated that it encodes a dehydrin with a native molecular mass of ∼40 kDa instead of 60 kDa. Experiments to determine if the dehydrins undergo post-translational modifications revealed that the 65- and 60-kDa dehydrins are glycosylated. Thus, our results indicate that the 2.0-kb dehydrin cDNA encodes the native version of the 60-kDa dehydrin. The dehydrin cDNA hybridized on RNA blots to two chilling/cold-responsive messages of 2.0 and 0.5 kb. Both the 2.0- and 0.5-kb messages increased to higher levels more quickly in the cold-hardy cultivar Bluecrop than in the less hardy cultivar Tifblue. In addition, the 0.5-kb message remained at a higher level longer in Bluecrop than in Tifblue. [ABSTRACT FROM AUTHOR]