Clay mineral associations in saprolite of two andesites from the Cascade Range of northeastern California were determined. Sesquioxidic allophane with a high CEC delta value dominates the clay fraction of the least weathered saprolite in each series (47% and 37% in hypersthene andesite and olivine andesite saprolites, respectively). With further weathering, the content of amorphous clay remains high (over 30% in all cases) but the CEC delta value of the clay drops markedly. The amorphous material in the more weathered saprolite has the properties of halloysitic allophane. Halloysite, present in all saprolites, is highest in concentration (over 30%) in the more strongly weathered members of each of the saprolite series. Formation of sesquioxidic allophane during early stages of weathering and its transformation to halloysitic allophane and halloysite during later stages of weathering are supported by X-ray diffraction, electron microscopic, DTA, elemental analysis, and CEC delta value data.

Understanding the views of those working along the value chain reliant on livestock is an important step in supporting the transition towards more sustainable farming systems. We recruited 31 delegates attending the Pig Welfare Symposium held in the United States to participate in one of six focus group discussions on the future of pig farming. Each of these six group discussions was subjected to a thematic analysis that identified four themes: (1) technical changes on the farm; (2) farm and industry culture; (3) the farm-public interface; and (4) sustainability. The results of this study illustrate the complexity and diversity of views of those working along the associated value chain within the swine industry. Participants spent the majority of their time discussing current challenges, including technical challenges on the farm and public perception of pig farms. Participants were more hesitant to discuss future issues, but did engage on the broader issue of sustainability, focusing upon economic and environmental aspects.

Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as the neutrino target, has emerged as perhaps the most promising technique for detection of extragalactic ultra-high energy neutrinos (corresponding to neutrino energies in excess of 0.01 Joules, or 1017 electron volts). During the summer of 2021 and in tandem with the initial deployment of the Radio Neutrino Observatory in Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, Greenland to refine our understanding of the ice target. We report the result of one such measurement, the radio-frequency electric field attenuation length $L_\alpha$. We find an approximately linear dependence of $L_\alpha$ on frequency with the best fit of the average field attenuation for the upper 1500 m of ice: $\langle L_\alpha \rangle = ( ( 1154 \pm 121) - ( 0.81 \pm 0.14) \, ( \nu /{\rm MHz}) ) \,{\rm m}$ for frequencies ν ∈ [145 − 350] MHz.

The coronavirus disease 2019 (COVID-19) pandemic continues to present unique public health challenges both within the United States and across the globe. Institutions of higher learning are tasked with preventing and responding to COVID-19 on campus while also considering implications for the surrounding communities. The process of re-opening campus, whether at full or partial capacity, has tasked these institutions with overcoming complex challenges associated with balancing the resumption of campus operations while simultaneously protecting university affiliates and surrounding community members from COVID-19 through robust surveillance, contact tracing, and testing efforts. Here, we provide a concise outline related to the development and implementation of the comprehensive and sustainable COVID-19 surveillance program at the University of Florida. We also critically discuss the successes and pitfalls of this program while also providing recommendations for the development of similar programs in the future.

Results of helicopter-borne electromagnetic measurements of total (ice plus Snow) Sea-ice thickness performed in May 2004 and 2005 in the Lincoln Sea and adjacent Arctic Ocean up to 86˚N are presented. Thickness distributions South of 84˚N are dominated by multi-year ice with modal thicknesses of 3.9 m in 2004 and 4.2 m in 2005 (mean thicknesses 4.67 and 5.18 m, respectively). Modal and mean Snow thickness on multi-year ice amounted to 0.18 and 0.30 m in 2004, and 0.28 and 0.35 m in 2005. There are also considerable amounts of 0.9–2.2m thick first-year ice (modal thickness), mostly representing ice formed in the recurring, refrozen Lincoln Polynya. Results are in good agreement with ground-based electromagnetic thickness measurements and with ice types demarcated in Satellite Synthetic aperture radar imagery. Four drifting buoys deployed in 2004 between 86˚N and 84.5˚N Show a Similar pattern of a mean Southward drift of the ice pack of 83 ±18km between May 2004 and April 2005, towards the coast of Ellesmere Island and Nares Strait. The resulting area decrease of 26% between the buoys and the coast is larger than the observed thickness increase South of 84˚ N. This points to the importance of Shear in a narrow band along the coast, and of ice export through Nares Strait in removing ice from the Study region.

Studies of the pedogenic iron oxyhydroxides in suites of latest Holocene to middle Pleistocene soils formed on fluvial deposits of the transverse ranges, southern California, indicate that the content and composition of iron oxyhydroxide change in a systematic manner. Analysis of total secondary free iron oxides (dithionite extractable, Fe2O3d) and ferrihydrite (oxalate extractable, Fe2O3o) shows that (1) a single-logarithmic model (Y = a + b log X) or double logarithmic model (log Y = a + b log X), where Y is the total mass of pedogenic Fe oxides (g/cm2-soil column) and X is soil age, describes the rate of increase in Fe2O3d with time; (2) the Fe2O3d content correlates linearly with soil reddening and clay content; (3) the Fe2O3oFe2O3d ratio, which indicates the degree of Fe oxide crystallinity, is moderately high to very high (0.22–0.58) in middle Holocene to latest Pleistocene soils and progressively decreases to less than 0.10 in older soils; (4) the value of the Fe2O3oFe2O3d ratio also appears to be infuenced by climate; and (5) temporal changes in Fe oxide content and mineralogy are accompanied by related, systematic changes in clay mineralogy and organic matter content. These relationships are attributed to a soil environment that must initially favor ferrihydrite precipitation and/or organic matter-Fe complexation. Subsequent transformation to hematite causes increasingly intense reddening and a concomitant decrease in the Fe2O3oFe2O3d ratio. The results demonstrate that iron oxide analysis is useful for numerical age studies of noncalcic soils and shows potential as an indicator of paleoclimates.

Previously, the single nucleotide polymorphism in alcohol dehydrogenase (ADH1C c.-64T>C) was shown to have an association with intramuscular fat (IMF) in the longissimus thoracis (LT) muscle when vitamin A was limited in finishing rations of beef steers. The purpose of this study was to determine the optimum vitamin A supplementation level, in combination with ADH1C genotype, to increase IMF of the LT muscle. In total, 45 TT genotype, 45 CT and 27 CC Black Angus crossbred steers were backgrounded on a commercial ration containing 3360 IU vitamin A/kg dry matter (DM). During finishing, the steers were randomly assigned to one of three vitamin A treatments at 25%, 50% and 75% of the National Research Council recommendation of 2200 IU/kg DM. Treatments were administered via an oral bolus. Carcass quality was evaluated and a sample from the LT muscle was collected for analysis of IMF. A treatment×genotype interaction (P=0.04) was observed for IMF; TT steers on the 75% treatment had higher IMF relative to CT and CC steers on the same treatment. Western blot analysis showed that TT steers had higher (P=0.02) ADH1C protein expression in hepatic tissue. Previously, TT steers exhibited increased IMF when fed limited vitamin A. In the current study, the lack of variation in IMF between treatments and genotypes at the lower vitamin A treatment levels was likely due to the majority of the steers grading Canada AAA (USDA Choice). However, the western blot data supports that TT steers are expected to have higher IMF deposition, due to an increased production of ADH1C. The interaction between ADH1C genotype and vitamin A supplementation level has the potential for use in marker-assisted management programs to target niche markets based on increased marbling.

Background: Neuropsychological studies of the pattern and extent of cognitive impairment in HIV-infected patients have mostly used deviations from control values and/or cut-off scores as criteria for classification of dementia. There is, however, no agreement as to how to define impairment, and classification is imprecise. Method: The current study used a dementia classification matrix, developed with a step-wise linear discriminant analysis of neuropsychological data from patients with primary neurodegenerative dementias, to classify symptomatic HIV patients as demented or non-demented, and further to differentiate cortical and subcortical dementia patterns. Thirty-two male and 2 female patients (mean age 39 ± 2) with symptomatic HIV disease (mean absolute CD4 count 195 ±41) participated in the study. Results: Thirty-five per cent of patients were classified as demented. Of these, 83% showed a subcortical pattern and 17% a cortical profile of deficits. Significant differences between patients classified as subcortically demented and those categorized as normal on neuropsychological measures associated with subcortical integrity further validated the classification. Measures of psychiatric status between subgroups were similar. Conclusion: Since certain treatments may delay or reverse cognitive deficits, the use of an objective classification method based on discriminant analysis may help to identify patients who may benefit from therapy.

Despite the great capacity for the pediatric brain to recover from stroke, the morbidity and mortality in children who harbor an arteriovenous malformation (AVM) remains high. This study examines the clinical data and management experience with 132 patients with brain AVM from 1949 to 1989. Although the high tendency for a childhood AVM to present with hemorrhage (79%) remained constant for the forty year study period, the associated morbidity and mortality of hemorrhage changed. The mortality rate from hemorrhage for the entire series was 25%, which was reduced from 39% to 16% after the introduction of computed tomography. The mortality from AVM hemorrhage since 1975 was dependent on location; 8 of 14 patients (57%) with a cerebellar AVM died from hemorrhage while only 2 of 44 patients (4.5%) with a cerebral hemisphere AVM died (p < 0.0001). Sixteen children (12%) presented with a chronic seizure disorder. Surgical excision of the malformation resulted in complete seizure control off anti-convulsant medication in 73% of patients. Although 21% of patients were treated non-operatively (many with terminal poor-grade hemorrhage), 79% had a surgical procedure with total AVM excision achieved in 70 patients (53.1%). Complete AVM resection was followed by a normal neurological outcome in 47 children (67%). Most partial excisions (n=9) and clipping of feeding arteries (n=7) were performed in the early years of this study, and did not provide protection from rehe-morrhage. Although conservative management has been advocated for selected non-hemorrhagic AVMs, we conclude that essentially all children with an AVM should be treated in order to eliminate the risk of hemorrhage. Long-term conservative management in pediatric patients is warranted only in patients with large AVMs not amenable to treatment using current multimodality techniques.

Vitamin D deficiency has been implicated in the aetiology of infectious diseases and metabolic syndrome. These diseases are prevalent in the African and Asian-Indian populations of South Africa; however, there is limited data on 25-hydroxyvitamin D (25(OH)D) concentrations in these populations. The aim of the present study was to assess the vitamin D status and its predictors in healthy adults in Johannesburg. We assessed the vitamin D status of 730 adult African and Asian-Indian subjects residing in Johannesburg. The contributions of sun exposure, season, dietary intake of Ca and vitamin D, total body fat and body fat distribution to 25(OH)D concentrations were assessed. The concentrations of 25(OH)D were measured by HPLC. The contribution of 25(OH)D3 to total 25(OH)D concentrations was assessed. The mean age of the subjects was 42·6 (sd 13·1) years (range: 18–65). Concentrations of 25(OH)D < 30 nmol/l were found in 28·6 % of the Asian-Indian subjects in comparison with 5·1 % of the African subjects (P< 0·0001). Parathyroid hormone (PTH) concentrations were negatively associated with 25(OH)D concentrations, while season and sun exposure were positive predictors explaining 16 % of the variance in 25(OH)D concentrations (P< 0·0001) in the African subjects. In the Asian-Indian subjects, PTH concentrations were negatively associated with 25(OH)D concentrations, while male sex, season and Ca supplementation were positive predictors and explained 17 % of the variance in 25(OH)D concentrations (P< 0·0001). In the multivariate regression analysis, neither total body fat nor body fat distribution was predictive of 25(OH)D concentrations in either group. In conclusion, factors such as sun exposure, dietary supplement use and ethnicity are important determinants of plasma 25(OH)D concentrations.

Background: Adolescents are prone to sleep problems that have unique developmental aspects and contribute to physical, emotional, and behavioural problems. Aims: This study evaluated an individualized, multicomponent intervention that considered developmental factors, and promoted age-appropriate autonomy in three adolescent females with disrupted sleep. Method: Adolescents recorded sleep data on daily logs. A nonconcurrent multiple baseline design was used to evaluate a cognitive-behavioural intervention including sleep hygiene training, bedtime routine development, cognitive restructuring, relaxation training, stimulus control, sleep restriction, bedtime fading, and problem-solving, along with clinically indicated individualization. Results: Outcomes demonstrated clinically meaningful improvements and decreased variability in sleep parameters following intervention. Each participant's sleep log data indicated improvement in, or maintenance of, adequate total sleep time (TST), decreased sleep onset latency (SOL), improved sleep efficiency (SE), improvement in time of sleep onset, and decreased or continued low frequency of night awakenings (NA). Anecdotally, adolescents and parents reported improvement in daytime functioning, coping, and sense of wellbeing. Conclusions: These cases highlight the potential for cognitive-behavioural interventions to facilitate healthy sleep in adolescents with challenging sleep problems.