Isotopes of strontium, oxygen, and carbon were analyzed in human tooth enamel from two Postclassic sites in the central Peten lakes region, Guatemala, to examine patterns of mobility and diet during a time of social unrest. Excavations at both sites, Ixlu and Zacpeten, have revealed evidence for purposeful dismemberment and interment of individuals. This study examines a possible shrine surrounded by rows of skulls at Ixlu, and a mass grave of comingled individuals interred at Zacpeten. The interments coincide with a period of conflict and warfare between two dominant polities, Itza and Kowoj. The 14 sampled individuals at Ixlu were young males, six of whom isotopically match the Maya Mountains of central Belize/southeastern Peten. At Zacpeten, isotopic signatures of adults and children (n = 68) suggested that many were either local or came from other parts of the Maya lowlands, but not the Maya Mountains. In the Late Postclassic, the Zacpeten individuals were exhumed, defiled, and deposited in a mass grave, probably by Kowojs. Although temporally and geographically related, the Ixlu and Zacpeten burials represent two distinct cases of ritual violence that reflect the tumultuous political landscape of the Postclassic period.

Sorption of the herbicide isoxaflutole and its main degradate, diketonitrile (DKN), to natural clays, SAz-1, SWy-2 and SHCa-1, and the organoclay derivatives (octadecylammonium (ODA) and hexadecyltrimethylammonium (HDTMA)) of these clays was investigated. Isoxaflutole hydrolysis to DKN was too rapid in aqueous solutions with organoclays to characterize sorption. No measurable DKN sorption was observed for the natural clays. Sorption of DKN was greater on organoclays with an interlayer paraffin-like complex that were prepared from the high-charge SAz-1 clay than on organoclays with a bilayer or monolayer interlayer complex prepared using lower-charge SWy-2 or SHCa-1 clays. Desorption isotherms indicated that sorption was irreversible. For SAz-1 with HDTMA at ∼100% of the clay CEC, the d001 values suggest that DKN enters the interlamellar space of the organoclay and dissociates into the anion. The DKN anion forms a very stable chelate complex with the residual cations and/or partially-coordinated structural cations. This strong interaction supports the irreversibility of the sorptive process.

Early in the COVID-19 pandemic, the World Health Organization stressed the importance of daily clinical assessments of infected patients, yet current approaches frequently consider cross-sectional timepoints, cumulative summary measures, or time-to-event analyses. Statistical methods are available that make use of the rich information content of longitudinal assessments. We demonstrate the use of a multistate transition model to assess the dynamic nature of COVID-19-associated critical illness using daily evaluations of COVID-19 patients from 9 academic hospitals. We describe the accessibility and utility of methods that consider the clinical trajectory of critically ill COVID-19 patients.

Fresh and weathered biotites have been studied using Mössbauer, chemical, and X-ray analytical techniques. In the Mössbauer spectra the complete interference of both low-spin ferric lines by one of the high-spin ferrous lines and the existence of high-spin ferric iron in the weathered biotite has been demonstrated. In view of this interference, which appears to be common, allowances must be made in spectral interpretation if chemical analysis reveals ferric iron to be present in detectable amounts. Hypothetical extension of the weathering trends observed suggests that high-spin ferric iron is the only stable iron species in the end product.

During weathering marked loss of ferrous iron occurs, whereas the ferric iron content remains approximately constant. As a result of the instability of ferrous iron in the weathering environment there is a significant rearrangement of the octahedral layer.

New experimental and theoretical studies of low-density amorphous solid water (H2O(as)) and of polycrystalline ice lh are reported and integrated with other available data. A variety of evidence is put forward to support the conclusion that low-density H20(as) is derived from ice lh by slightly increasing the dispersion in the O—O separation and by introducing a distribution O—O—O angles (width c. 8°). Our theoretical analysis focusses attention on the consequences of strong intermolecular coupling of OH oscillators. The vibrational modes of both ice lh and H20(as) are found to be complex mixtures of molecular motions, so the identification of regions of the Raman or infrared spectra of these materials with particular isolated molecule modes is not useful. The theory developed gives a good, but not perfect, account of the OH stretching regions of the observed Raman and infrared spectra of ice lh and, to a lesser degree of low-density H20(as).

The innermost parsec around Sgr A* has been found to play host to two disks or streamers of O and W-R stars. They are misaligned by an angle approaching 90°. That the stars are approximately coeval indicates that they formed in the same event rather than independently. We have performed smoothed particle hydrodynamic simulations of the infall of a single prolate cloud towards a massive black hole. As the cloud is disrupted, the large spread in angular momentum can, if conditions allow, lead to the creation of misaligned gas disks. In turn, stars may form within those disks. We are now investigating the origins of these clouds in the Galactic center (GC) region.

The styli, often called the aristae, of the antennae of adult Sepedon fuscipennis Loew (Diptera: Sciomyzidae) are shown to possess mechanosensilla, the number and arrangement of which differ between the sexes. It is suggested that the mechanosensilla provide sensory input to the female regarding the touching, or appositioning, of her styli by the male with his forelegs during copulation. Among the Sciomyzidae, S.fuscipennis males are unique in appositioning the antennae of the female during mating. Large clusters of pollen found on the styli of both sexes suggest that mechanosensilla and chemosensilla also provide sensory information about potential sources of food such as nectar (i.e., carbohydrates).

During studies on different aspects of cricket (Orthoptera: Gryllidae) biology in Hawaii, we observed many toads, Bufo marinus (L.), in areas inhabited by the field crickets Teleogryllus oceanicus (Le Guillou) and Modicogryllus conspersus Walker. The research reported here was intended to determine if B. marinus is a predator of these crickets and, if so, the relative amount of predation on each. We also tested the possibility that B. marinus locates crickets by orienting to cricket acoustical signals.

Objectives: There is evidence that breastmilk feeding reduces mortality and short and long-term morbidity among infants born too soon or too small. The aim of this study was to evaluate the cost-effectiveness of enhanced staff contact for mothers with infants in a neonatal unit with a birth weight of 500–2,500 g from the perspective of the UK National Health Service.

Methods: A decision-tree model linked clinical outcomes with long-term health outcomes. The study population was divided into three weight bands: 500–999 g, 1000–1,749 g, and 1,750–2,500 g. Clinical and resource use data were obtained from literature reviews. The measure of benefit was quality-adjusted life-years. Uncertainty was evaluated using cost-effectiveness acceptability curves and sensitivity analyses.

Results: The intervention was less costly and more effective than the comparator in the base–case analysis for each birth weight group. The results were quite robust to the sensitivity analyses performed.

Conclusions: This is the first economic evaluation in this complex field and offers a model to be developed in future research. The results provide preliminary indications that enhanced staff contact may be cost-effective. However, the limited evidence available, and the limited UK data in particular, suggest that further research is required to provide results with confidence.

Analysis of pelites with detrital white-micas in the Clew Bay–Galway Bay segment of the Irish Caledonides indicates that b0 data from whole-rock and < 2 μm fractions generally show differences smaller than the errors of the method, irrespective of (001) illite crystallinity values, probably due to metamorphic recrystallization. Intermediate pressure metamorphism of the Ordovician–Silurian Clew Bay Group indicates slow subduction, allowing partial thermal re-equilibration before exhumation. In contrast, the Croagh Patrick Group Laurentian shelf-sediments underwent high-pressure alteration, suggesting rapid subduction/exhumation, synchronous with strike-slip faulting. The Murrisk Group, which underwent high-intermediate pressure metamorphism in an Ordovician back-arc, forms a separate terrane to the Croagh Patrick Group to the north and also to the Ordovician Lough Nafooey and Tourmakeady groups and Rosroe Formation in the south, in which low-intermediate pressure alteration occurred. These, together with the Silurian North Galway Group, may have undergone heating due to movement over or deposition on the hot Gowlaun Detachment as the Connemara Dalradian was exhumed. The South Connemara Group also underwent a high-pressure alteration, consistent with its inferred subduction environment. Evidence of contact alteration, due to known or inferred buried late- to post-Caledonian granitoid plutons, has been found in the Clew Bay, Louisburg–Clare Island, Croagh Patrick, Murrisk and South Connemara groups. These show evidence of lower-pressure alteration than the surrounding country-rocks.

The physics problems remaining to be solved to achieve practical fusion power by magnetic confinement techniques are believed to be well posed and soluble. A programme plan recently developed in the United States calls for progressively larger plasma confinement experiments to address these physics questions in line with a serious programme in fusion power engineering. Implementation of the plan is expected to lead to the first production of power from a deuterium–tritium-fuelled system in 1980. Thereafter, three progressively larger experimental electrical power reactors are planned, leading to fusion power commercialization in the later 1990s.

The environmental characteristics of fusion reactors have been estimated by analyzing conceptual reactor designs. It is projected that the only volatile radioactive material in a fusion power-plant will be the tritium fuel. Analyses indicate that tritium leakage can be held to very low levels and accordingly should not pose a significant environmental hazard.

Careful selection of the materials of construction of a fusion reactor core will minimize radioactivity induced by neutron activation. This activity will be nonvolatile, and it can be isolated from the environment by the use of existing techniques. Because this induced activity is short-lived, it does not represent a long-term storage problem.

Anticipated thermal efficiencies of fusion powerplants range from present-day levels (30–40%) using standard conversion systems to about 50% when more exotic techniques (such as liquid-metal topping cycles) are utilized.

1. The total exchangeable bases, clay, total carbon and carbon oxidisable by 4 per cent, hydrogen peroxide, have been determined for a number of carbonate soils.

2. Assuming soils containing excess of carbonate under natural conditions to be base saturated, equations have been derived connecting exchange capacity with clay and (a) total or (b) “oxidisable” carbon content.

3. When the organic matter of these soils was assumed to have a constant base exchange capacity, no correlation was found between the exchange capacity of their clay fractions and either their silica-alumina or their silica-sesquioxide ratios.

4. Carbonate soils whose exchangeable base content was appreciably less than the calculated values were found to contain either small amounts of calcium carbonate (< 1 percent.), or the bulk of it was present in coarse form.

(1) Exchangeable magnesium and potassium can be determined in carbonate-free soils by the use of 0.5 N acetic acid as a leaching agent.

(2) A method is described for the determination of the total exchangeable bases present as acetates in the leachings.

(3) The results obtained by this method differ from those obtained by summation of separate determinations by an amount equivalent to the sulphates and chlorides present.

(4) It is suggested that the total exchangeable bases by the proposed method gives a truer measure of the exchangeable bases than methods in which bases present as sulphates and chlorides are also reckoned in.

A method for determining the total exchangeable bases of carbonate soils is described. The carbonate in a known weight of soil is decomposed by acetic acid and the carbon dioxide evolved is estimated. By further extraction with acetic acid a solution is obtained which contains not only the bases originally in combination with the carbon dioxide but also the exchangeable bases. The amount of the latter is found by difference.

(1) The possibility of using acetic acid as a reagent for extracting exchangeable calcium from carbonate-free soils is discussed, and experimental results are given showing that calcium is quantitatively precipitated from an acetic acid medium.

(2) A method for determining exchangeable calcium using 0·5 N acetic acid is described, and figures are given comparing this proposed method with the Hissink method.

(3) A modification of the proposed method is suggested in the case of heavy clay soils owing to the impervious nature of these soils which probably does not allow the acid to penetrate through the whole mass of the soil when leached on the filter paper.