Corncobs in the Campfire: Evidence of Cultivation of Zea mays at 44CH62, The Randy K Wade Site

In 20 years of excavation, the Randy K. Wade site (44CH62) has only produced indirect evidence of the cultivation of corn (Zea mays) in the Late Woodland village. This indirect evidence consists primarily of corncob impressions on Dan River pottery. In the summer of 2017, an intact hearth was excavated which contained the preserved remains of multiple charred corncobs- the first direct evidence of corn. The hearth also contained remains of other organic materials such as charred corn kernels, bark, sticks, bone fragments, and acorns. This paper will examine the direct evidence for corn cultivation at the Wade site and how this fits into the broader context of Dan River sites in the southern piedmont of Virginia

Effect of a zero g environment on flammability limits as determined using a standard flammability tube apparatus

Flammability limits in a zero gravity environment were defined. Key aspects of a possible spacelab experiment were investigated analytically, experimentally on the bench, and in drop tower facilities. A conceptual design for a spacelab experiment was developed

Chemical Ecology of Nematodes

Nematodes represent the most abundant group of metazoans on earth. They utilize diverse chemicals to interact with con-specific and hetero-specific organisms, and are also impacted by compounds produced by other interacting organisms. In the first part of this review we discuss how nematode-derived glycolipids modulate their behavior and development, as well as the interactions with other organisms. Furthermore, we provide a short overview about other secondary metabolites produced by nematodes that affect different life traits of free-living nematodes. In the second part of this review we discuss how different bacteria-, nematode-, and plant-derived chemicals such as volatile organic compounds, root exudates, and plant defenses regulate the interaction between entomopathogenic nematodes, their symbiotic bacteria, insect prey, predators, and plants

Renal tract anomalies in the human fetus : prenatal ultrasound and genetic aspects.

In this thesis, attention will be focused on:(i) ultrasonic imaging of normal and abnormal fetal urinary tract anatomy;(ii) the reduced diagnostic potential of ultrasound in oligohydramnios, including methods to circumvent this problem; (iii) the association of ren al tract malforma ti ons and extrarenal and chromosomal anomalies which may have a decisive impact on obstetrie management. The objectives of the present study were: a. to define the role of ultrasound in the prenatal diagnosis of fetal urinary tract malforma ti ons, with particular reference to bilateral renal agenesis, cystic kidney disease and obstructive uropathy; b. to document the incidence and nature of associated extra-renal and chromosome anomalies; c. to assess perinatal outcome following prenatal diagnosis of a fetal urinary tract malformation; d. to establish the possibilities and Iimitations of prenatal ultrasound scanning in pregnancies at risk for a particular renal tract malformation; e. tb determine the potential of intra-uterine diversion techniques in obstructive uropathy

Regulation of connexin 43 channels by PKC-mediated phosphorylation

Gap-junctional channels communicate adjacent cells electrically and metabolically. They are formed by 4-transmembrane helix proteins called connexins; six connexins form a connexon (or gap-junctional hemichannel) and two of these, one from each neighboring cell, dock head-to-head to form the gap-junctional channel. The permeability of gapjunctional channels is regulated by voltage, intracellular calcium activity, intracellular pH and phosphorylation by various kinases. This review focuses on the mechanism of the regulation of connexin 43 by protein kinase C. We discuss results obtained largely from studies of hemichannels that demonstrate that the channel pore is narrowed down, but not closed, by protein kinase C-mediated phosphorylation of a single site, serine 368, located 14 residues away from the C-terminal end of connexin 43. The effect of protein kinase C involves a large conformational change of the protein and requires phosphorylation of all six subunits. The precise mechanism of the decrease in pore cross-sectional area has not been established.Sociedad Argentina de Fisiologí

Prenatal diagnosis, management and outcome of fetal uretero-pelvic junction obstruction

Abstract Prenatal diagnosis, management and outcome were studied retrospectively in 24 cases of unilateral and bilateral uretero-pelvie junction obstruction (UPJO). Moderate-to-marked pelvic dilatation was documented in 19 out of 24 cases. The low morbidity and mortality observed in this study are probably determined by the late (third trimester) detection of UPJO, resulting in an underestimation of the prevalence of more severe renal pathology. Amniotic fluid was increased in 4 out of 14 cases of unilateral UPJO and in 5 out of 10 cases of bilateral UPJO, the underlying mechanism of which is still unclear. There was no oligohydramnios. The incidence of extrarenal structural pathology was low, i.e., 3 out of 24 cases. A close agreement could be demonstrated between pre- and postnatal sonographic grading of pelvic dilatation. However, postnatal ultrasonic grading of pelvic dilatation correlated poorly with the degree of functional obstruction as determined by IVP and lasix renography. Despite the severity of pelvic dilatation in the majority of cases, enlarged kidneys were revealed by postnatal clinical examination in only three instances, underlining the importance of prenatal sonographic detection of UPJO

Prenatal diagnosis by ultrasound in pregnancies at risk for autosomal recessive polycystic kidney disease

Abstract In 15 pregnancies at risk of the autosomal recessive type of polycystic kidney disease (ARPKD), there were six recurrences (40%), five of which were diagnosed prenatally between 17 and 26 weeks (mean, 22 weeks). In the remaining affected case, normal kidney size and echogenicity were still present at 30 weeks of gestation. Fetal kidney enlargement and increased echogenicity are the key ultrasonographic signs for the detection of ARPKD. Absent fetal bladder filling and oligohydramnios were only documented in two of the six affected pregnancies. The variability in onset, the intrafamilial variability and the limitations of excluding ARPKD by second trimester ultrasound have to be considered when counselling a couple at risk for this particular disorder