The principal aim of the present experiments was to assess whether punishment increased or decreased the rate of unpunished behavior (contrast and induction, respectively) for which reinforcement rate was held constant, with physical and nonphysical punishers (electric shock and response cost), pigeon and human subjects, signaled and unsignaled components (multiple and mixed schedules), and the presence or absence of a blackout period between components. Across the three experiments there were 20 punishment conditions. Induction was found in nine of those, less consistent response‐rate reduction was found in three, contrast was found in four, and in four there was no change in responding from conditions without punishment. Contrast occurred consistently only with multiple schedules during the first exposure to electric‐shock punishment. Induction and no change, however, were found with every combination of the independent variables studied. Four conclusions regarding the interactions between punished and unpunished responding emerged from the present results: (a) Both contrast and induction occurred with the reinforcement rate held constant and a blackout between components, (b) induction was more common than contrast, (c) contrast occurred only in the presence of a stimulus different from that correlated with the punisher, and (d) contrast diminished with prolonged exposure to punishment. None of the current theoretical accounts of punishment contrast can explain the present results.
We examined the regulation of the cellular thymidine kinase (TK) gene promoter in simian virus 40 (SV40)-infected simian CV1 cells. Nuclear run-on transcription assays demonstrated a threeto fourfold increase in the rate of transcription of the endogenous gene at 14 to 16 h following viral infection. In addition, hybrid genes containing the human TK promoter linked to the bacterial neomycin resistance gene were induced by SV40 in stably transfected cells, indicating that promoter sequences are sufficient to confer viral regulation. Analysis of human TK promoter deletion mutants indicated that sequences localized between-67 and +30 bp relative to the transcriptional initiation site are sufficient to confer regulation on SV40-infected cells. These sequence elements are distinct from those required for serum induction, which were previously localized to the region between-135 and-67. These results suggest that SV40 activates novel cellular pathways that are not activated by serum stimulation of quiescent cells.
Rivers and wetlands are a major source of terrestrial derived carbon for coastal ocean margins. This results in a net loss of terrestrial carbon into the shelf water and their subsequent transport to interior ocean basin. This study investigates the transport of dissolved inorganic carbon (DIC) in the surface-mixed layer of Louisiana Shelf in northern Gulf of Mexico (nGOM) adjacent to the Wax Lake Delta (WLD) and Barataria Bay (BB), which represent contrasting net land gain and net land loss areas in this region. DIC samples were collected, in conjunction with short-lived radium isotopes 224 Ra (t 1/2 = 3.66 days) and 223 Ra (t 1/2 = 11.43 days) samples during June and September 2019, to quantify shelf transport of DIC in the surface-mixed layer during period of high and low river flow, respectively. Radium distribution implied shelf mixing rates of 140-6,759 and 63-2,724 m 2 s −1 for WLD and BB regions, respectively, with more than tenfold decrease in rates between the two seasons. Net shelf transport of DIC was found to be highest for the WLD region in June, highlighting the importance of freshwater discharge in exporting DIC. An upscaling of our study for the entire Louisiana Shelf indicates that 1.54-20.19 × 10 9 mol C d −1 transported in June 2019 and 0.34-8.12 × 10 9 mol C d −1 in the form of DIC was exported across the shallow region of the shelf during high and low river flow seasons, representing an important source of DIC to the NGOM. Plain Language Summary Rivers and wetlands are a major source of terrestrial derived carbon for coastal ocean margins. This results in a net loss of terrestrial carbon into the shelf water and their subsequent transport to interior ocean basin, which are currently not well constrained. In the current study, we used naturally occurring short-lived radium radioisotopes to understand the transport of dissolved inorganic carbon across the Louisiana Shelf in northern Gulf of Mexico. This region receives a large amount of dissolved carbon from the Mississippi-Atchafalaya River System as well as coastal wetland loss, but the fate and transport of this carbon is not well documented. Our study indicates that the DIC transport across the Louisiana Shelf can vary from 0.02-0.24 to 0.03-0.09 Tg C d −1 during high and low river flow seasons, representing an important source of DIC to the Gulf of Mexico that is predominately controlled by river discharge. Current predictions suggest that Mississippi-Atchafalaya River discharge to coastal waters may increase by up to 60% by 2090, which would have dramatic impact on the lateral export of both carbon and nutrients to the ocean interior in the future.
Background and purpose Current trends in parental decision making involve alteration from vaccine schedules in children, citing concerns for altered immune function. The purpose of this study was to determine if there is a difference in incidence of common childhood illnesses dependent on vaccination status. Methods An investigator‐designed survey was administered to parents of children aged 12 months to 7 years. Participants were separated into one of three groups: fully vaccinated, partially vaccinated, and unvaccinated. There were 111 total participants. Power analysis indicated a minimum of 30 participants per group to detect an 80% effect. Descriptive statistics were applied to variables with chi‐square for group comparison. Conclusions The results indicated a statistically significant difference between all three groups in the categories of ear infections, influenza, and common colds. Fully immunized group had significantly more ear infections than partial or unimmunized. The unimmunized group had significantly more colds and flu. Implications for practice Nurse practitioner practice implications relate directly to further education of parents, support, and trust building. Many parents question the possible association between childhood vaccines and immune function and have a distrust of current research. This study showed that most common childhood illnesses are equitable across the population and not dependent on vaccine status.
Infection of quiescent cells with the DNA tumor virus simian virus 40 induces expression of the cellular thymidine kinase (TK) gene a minimum of 10-to 20-fold, and this induction depends upon the viral protein large T antigen (T-Ag). To define both human TK promoter elements and TAg functional domains required for transcriptional induction, we have established a system in which stable Rat-1 transfectants harboring TK promoter-luciferase hybrid genes are infected with recombinant adenoviruses expressing either wild-type or mutant forms of TAg and luciferase expression is measured as an indicator of promoter activity. The results show that (i) a 135-bp TK promoter fragment is activated 10-to 15-fold by viral infection; (ii) this activation is the result of both TAg dependent and-independent mechanisms; (iii) the TAg pRb family-binding domain, but not the p53-binding, helicase, or ATPase domain, is required for activation; and (iv) activation is severely diminished with a TK promoter fragment in which E2F-like-binding sites have been removed. These data demonstrate a requirement for both an E2F-related factor and a pRb family member in activation of the TK promoter by TAg. This contrasts with the promiscuous activation of many cellular and viral genes by TAg , which is independent of its ability to bind pRb.
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