Persistent Place-Making in Prehistory: the Creation, Maintenance, and Transformation of an Epipalaeolithic Landscape

Most archaeological projects today integrate, at least to some degree, how past people engaged with their surroundings, including both how they strategized resource use, organized technological production, or scheduled movements within a physical environment, as well as how they constructed cosmologies around or created symbolic connections to places in the landscape. However, there are a multitude of ways in which archaeologists approach the creation, maintenance, and transformation of human-landscape interrelationships. This paper explores some of these approaches for reconstructing the Epipalaeolithic (ca. 23,000–11,500 years BP) landscape of Southwest Asia, using macro- and microscale geoarchaeological approaches to examine how everyday practices leave traces of human-landscape interactions in northern and eastern Jordan. The case studies presented here demonstrate that these Epipalaeolithic groups engaged in complex and far-reaching social landscapes. Examination of the Early and Middle Epipalaeolithic (EP) highlights that the notion of “Neolithization” is somewhat misleading as many of the features we use to define this transition were already well-established patterns of behavior by the Neolithic. Instead, these features and practices were enacted within a hunter-gatherer world and worldview

Dispersion as an Important Step in the Candida albicans Biofilm Developmental Cycle

Biofilms are dynamic microbial communities in which transitions between planktonic and sessile modes of growth occur interchangeably in response to different environmental cues. In the last decade, early events associated with C. albicans biofilm formation have received considerable attention. However, very little is known about C. albicans biofilm dispersion or the mechanisms and signals that trigger it. This is important because it is precisely C. albicans cells dispersed from biofilms that are the main culprits associated with candidemia and establishment of disseminated invasive disease, two of the gravest forms of candidiasis. Using a simple flow biofilm model recently developed by our group, we have performed initial investigations into the phenomenon of C. albicans biofilm dispersion, as well as the phenotypic characteristics associated with dispersed cells. Our results indicate that C. albicans biofilm dispersion is dependent on growing conditions, including carbon source and pH of the media used for biofilm development. C. albicans dispersed cells are mostly in the yeast form and display distinct phenotypic properties compared to their planktonic counterparts, including enhanced adherence, filamentation, biofilm formation and, perhaps most importantly, increased pathogenicity in a murine model of hematogenously disseminated candidiasis, thus indicating that dispersed cells are armed with a complete arsenal of “virulence factors” important for seeding and establishing new foci of infection. In addition, utilizing genetically engineered strains of C. albicans (tetO-UME6 and tetO-PES1) we demonstrate that C. albicans biofilm dispersion can be regulated by manipulating levels of expression of these key genes, further supporting the evidence for a strong link between biofilms and morphogenetic conversions at different stages of the C. albicans biofilm developmental cycle. Overall, our results offer novel and important insight into the phenomenon of C. albicans biofilm dispersion, a key part of the biofilm developmental cycle, and provide the basis for its more detailed analysis

Cocaine, d -amphetamine, and pentobarbital effects on responding maintained by food or cocaine in rhesus monkeys

The effects of IM injections of cocaine, d -amphetamine, and pentobarbital were studied in rhesus monkeys whose lever-press responding was maintained under a second-order fixed-interval, fixed ratio schedule of reinforcement. Within each session, fixed-interval components, ending with the IV injection of 30 μg/kg cocaine (one group of monkeys) or the delivery of a 300 mg food pellet (second group of monkeys), alternated with fixed-interval components ending without an injection of cocaine or the delivery of food (extinction). Drug pretreatments generally caused comparable dose-related decreases in the overall rates of responding reinforced either by cocaine or by food. Response rates during extinction usually increased and then decreased as the dose of each drug increased. An analysis of the drug effects on response rates in different temporal segments of the fixed intervals showed that in both the reinforcement and extinction components, the normally low control rates of responding which occurred earlier in the intervals were usually increased, while higher control rates which occurred later in the intervals were increased less or decreased. Thus, the effects of these drugs were relatively independent of the reinforcing event (food or cocaine) and tended to depend more on the ongoing rate of responding under these conditions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46409/1/213_2004_Article_BF00427508.pd

Women with pregnancies had lower adherence to 1% Tenofovir vaginal gel as HIV preexposure prophylaxis in CAPRISA 004, a phase IIB randomized-controlled trial.

Background: Antiretroviral prophylaxis may be a critical strategy to reduce periconception HIV transmission. Maximizing the benefit of periconception pharmacologic HIV risk-reduction requires an understanding of the links between pregnancy and adherence to this prevention strategy. Methods: We assessed study gel adherence among women with pregnancies compared to women without pregnancies enrolled in the CAPRISA 004 phase IIB trial of 1% vaginal tenofovir gel. Pregnancy was assessed with monthly urine tests. Adherence was measured monthly and defined as proportion of sex acts covered by two returned, used applicators based on pre- and post-coital dosing. High adherence was defined as a median adherence score of >80%, that is, more than 80% of sex acts were covered by two applications of study gel. A multivariate generalized estimating equations (GEE) model with a binomial distribution was used to assess covariates associated with high adherence (>80%) over time. Median adherence before and after pregnancy was compared using Wilcoxon signed rank test. Results: Among 868 women, 53 had at least 1 pregnancy (4.06 per 100 woman years, 95% CI: 3.04, 5.31). Women with pregnancies had lower median adherence compared to women without pregnancies (50% [IQR: 45–83] vs. 60% [IQR: 50–100], p = 0.02). Women with pregnancies also had a 48% lower odds of high adherence compared to women without pregnancies when adjusting for confounders (aOR 0.52, 95%CI: 0.41–0.66, p<0.0001). Among women with pregnancies, adherence before and after pregnancy was not different (50% [IQR: 46–83] vs. 55% [IQR: 20–100], p = 0.68). Conclusions: Women with pregnancies were less likely to have high adherence to study gel compared to women without pregnancies. Understanding these differences may inform findings from HIV prevention trials and future implementation of antiretroviral prophylaxis for at-risk women who choose to conceive. The protocol for the parent trial is registered on ClinicalTrials.gov, NCT00441298, http://www.clinicaltrials.gov/ct2/show/NCT00441298