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Recent fieldwork and archival sedimentary materials from southern Iraq have revealed new insights into the environment that shaped southern Mesopotamia from the pre-Ubaid (early Holocene) until the early Islamic period. These data have been combined with northern Iraqi speleothem, or stalagmite, data that have revealed relevant palaeoclimate information. The new results are investigated in light of textual sources and satellite remote sensing work. It is evident that areas south of Baghdad, and to the region of Uruk, were already potentially habitable between the eleventh and early eighth millennia B.C., suggesting there were settlements in southern Iraq prior to the Ubaid. Date palms, the earliest recorded for Iraq, are evident before 10,000 B.C., and oak trees are evident south of Baghdad in the early Holocene but disappeared after the mid-sixth millennium B.C. New climate results suggest increased aridity after the end of the fourth millennium B.C. For the third millennium B.C. to first millennium A.D., a negative relationship between grain and date palm cultivation in Nippur is evident, suggesting shifting cultivation emphasising one of these crops at any given time in parts of the city. The Shatt en-Nil was also likely used as a channel for most of Nippur's historical occupation from the third millennium B.C. to the first millennium A.D. In the early to mid-first millennium A.D., around the time of the Sasanian period, a major increase in irrigation is evident in plant remains, likely reflecting large-scale irrigation expansion in the Nippur region. The first millennium B.C. to first millennium A.D. reflects a relatively dry period with periodic increased rainfall. Sedimentary results suggest the Nahrawan, prior to it becoming a well-known canal, formed an ancient branch of the Tigris, while the region just south of Baghdad, around Dalmaj, was near or part of an ancient confluence of the Tigris and Euphrates.
Objectives: Sleep quality affects memory and executive function in older adults, but little is known about its effects in midlife. If it affects cognition in midlife, it may be a modifiable factor for later-life functioning. Methods: We examined the association between sleep quality and cognition in 1220 middle-aged male twins (age 51–60 years) from the Vietnam Era Twin Study of Aging. We interviewed participants with the Pittsburgh Sleep Quality Index and tested them for episodic memory as well as executive functions of inhibitory and interference control, updating in working memory, and set shifting. Interference control was assessed during episodic memory, inhibitory control during working memory, and non-memory conditions and set shifting during working memory and non-memory conditions. Results: After adjusting for covariates and correcting for multiple comparisons, sleep quality was positively associated with updating in working memory, set shifting in the context of working memory, and better visual-spatial (but not verbal) episodic memory, and at trend level, with interference control in the context of episodic memory. Conclusions: Sleep quality was associated with visual-spatial recall and possible resistance to proactive/retroactive interference. It was also associated with updating in working memory and with set shifting, but only when working memory demands were relatively high. Thus, effects of sleep quality on midlife cognition appear to be at the intersection of executive function and memory processes. Subtle deficits in these age-susceptible cognitive functions may indicate increased risk for decline in cognitive abilities later in life that might be reduced by improved midlife sleep quality. (JINS, 2018, 24, 67–76)
Anomalous origin of the right coronary artery from the posterior, non-coronary sinus is extremely rare and has never been reported in a paediatric-age competitive athlete. We report this very rare case of the right coronary artery arising from the posterior sinus. In the anomalous right coronary from the posterior sinus, the proximal right coronary artery appears widely patent and has no interarterial course.
The unrefined fold of Escherichia coli
β-galactosidase based on a monoclinic crystal form
with four independent tetramers has been reported previously.
Here, we describe a new, orthorhombic form with one tetramer
per asymmetric unit that has permitted refinement of the
structure at 1.7 Å resolution. This high-resolution
analysis has confirmed the original description of the
structure and revealed new details. An essential magnesium
ion, identified at the active site in the monoclinic crystals,
is also seen in the orthorhombic form. Additional putative
magnesium binding sites are also seen. Sodium ions are
also known to affect catalysis, and five putative binding
sites have been identified, one close to the active site.
In a crevice on the protein surface, five linked five-membered
solvent rings form a partial clathrate-like structure.
Some other unusual aspects of the structure include seven
apparent cis-peptide bonds, four of which are proline,
and several internal salt-bridge networks. Deep solvent-filled
channels and tunnels extend across the surface of the molecule
and pass through the center of the tetramer. Because of
these departures from a compact globular shape, the molecule
is not well characterized by prior empirical relationships
between the mass and surface area of proteins. The 50 or
so residues at the amino terminus have a largely extended
conformation and mostly lie across the surface of the protein.
At the same time, however, segment 13–21 contributes
to a subunit interface, and residues 29–33 pass through
a “tunnel” formed by a domain interface. Taken
together, the overall arrangement provides a structural
basis for the phenomenon of α-complementation.
To assess the degree to which, from 1987 to 1990, physicians suspected tuberculosis (TB) in the first 2 hospital days in human immunodeficiency virus (HIV)-infected patients with pulmonary disease.
Retrospective cohort study.
96 hospitals in five US cities.
2,174 adult patients with acquired immunodeficiency syndrome discharged with a diagnosis of Pneumocystis carinii pneumonia from 1987 to 1990. The diagnosis generally was not known on admission.
Physicians suspected TB in the first 2 hospital days in 66% of these patients in 1987, a rate that increased steadily to 74% in 1990. However, the extent to which physicians considered TB among female patients decreased from 76% to 71% over the 4 years. Controlling for confounding variables by multiple logistic regression, the odds that TB would be suspected early increased 1.8-fold among men (odds ratio [OR], 1.8; 95% confidence interval [CI95], 1.4-2.4), but not in women (OR, 0.6; CI95, 0.2-1.9). Among the five cities, the odds of early suspicion of TB increased most in New York City (OR, 3.9; CI95, 2.0-7.9).
Physicians considered TB in a timely manner in an increasing majority of male, but not female, high-risk patients during the first years of TB resurgence in the United States. Physicians must be aware of the changing epidemiology of HIV and TB, as well as their practice patterns, to prevent nosocomial transmission of this disease
The early stages of microwave-plasma assisted CVD of diamond on fused silica and silicon substrates were investigated. Nucleation densities on fused silica were somewhat lower than on silicon; however, the diamond growth rates on fused silica were faster. These results suggest that the substrate alters the plasma chemistry near the substrate. Transmission electron microscopy showed a relatively smooth interface between the diamond grains and the SiO2 surface. At low nucleation densities, the growth kinetics on both substrates were linear (i.e., the average feature size was proportional to the deposition time), which indicates that the growth kinetics were initially controlled by reaction(s) at the growing diamond surfaces. The transition to nonlinear growth kinetics observed at higher nucleation densities was probably caused by mass-transport limits.
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