The hypothesis tested was that macroscopic swelling of montmorillonitic clays is reduced by the presence of interlayer minerals. Fine and coarse clay fractions of Camargo and Panther Greek bentonite samples were artificially interlayered by reaction of Al2(SO4)3 and NaOH in 0∙5% suspensions of the clays. All four clay fractions reacted similarly to artificial interlayering. At an Al:clay ratio of 16 meq Al/g clay the CEC was completely lost, surface area was reduced and X-ray basal spacings were altered. No macroscopic swelling occurred in samples treated with 16 meq of Al/g of clay. At smaller concentrations of hydroxy-aluminum 8 and 2 meq Al/g clay, the clay properties were less drastically altered. Extraction of interlayered clays with Na citrate restored the original C.E.C., surface area, and basal spacings of all samples and resulted in some slight enhancement of C.E.C. and surface areas of the coarse fractions. Treatment with hot Na citrate resulted in an increase in swelling ability but only slight increases in C.E.C. and surface area. Evidence presented supports the hypothesis that macroscopic swelling of montmorillonitic clays is greatly reduced by interlayer materials. Reduced swelling due to interlayering occurs even when other clay properties may be slightly different from those of nontreated samples. Indications are that interlayer material occurs naturally in the clays studied and this may apply to other bentonite deposits.

This study was an investigation of the effects of sesquioxide constituents on some mineralogical and physiochemical properties of a Panamanian latosol.

Latosols are soils characterized by high concentrations of iron and aluminum oxides and a general absence of free silica and alkaline earths.

X-ray diffraction studies revealed sesquioxide coatings existed on the surfaces of the clay minerals. Mineralogically, the soil was composed of kaolin, amorphous minerals, hydrated iron and aluminum oxides, free silica, quartz grains, and magnetite. The results of DTA data suggested the presence of amorphous colloids in the soil. This suggestion was subsequently confirmed by selective dissolution analysis which revealed the unexpected presence of 17% amorphous silica in the coarse clay size fraction. Grain size analysis and scanning electron microscopy studies showed that the clay minerals are probably agglomerated by the sesquioxides into silt size clusters. CEC values obtained were primarily attributed to the amorphous colloids rather than the crystalline clay minerals because the sesquioxides probably partially blocked the exchange sites of the clays.

Removal of the iron and aluminum oxides by sodium dithionite citrate-bicarbonate procedures (Mehra and Jackson, 1960), (a) sharpened and exposed previously “masked” X-ray diffraction peaks, (b) disaggregated the clay clusters producing greater amounts of clay size particles, and (c) altered the Cation Exchange Capacity (CEC) and water retention characteristics of the soil constituents.

This investigation demonstrated that amorphous silica and iron and aluminum oxides greatly influence the properties of this latosol by coating and aggregating the clay minerals. These sesquioxide coatings suppress the ordinary behavioral characteristics of the indigenous clay minerals and consequently the observed behavior of the soil is dominated by the amorphous constituents.

This study reports novel information on the animal handling, management and human-animal interactions in Indonesian cattle abattoirs. The slaughter of 304 cattle was observed and there was a high percentage of re-stuns in all abattoirs (range: 8-18.9%) when compared to a variety of international auditing guidelines. The average stun-to-neck cut time was within international recommendations (average: 9 s; range: 4-15 s). Time spent in lairage varied between animals and facilities and was compliant with international guidelines. Handling times were extremely variable (2 s-23 min 40s), but were only weakly correlated with a variety of handler techniques including the total number of handler interactions (sum of visual, auditory and tactile interactions, suggesting that long handling time does not increase handler interactions. There was a moderate correlation between the subjective handling scale and most of the objective behaviours, indicating that this may be a useful way to summarise handler behaviour in future assessments. The current study provides novel information about animal welfare in Indonesian abattoirs and highlights that management practices at the four abattoirs generally comply with international standards. The results also suggest that the subjective handling scale was moderately associated with the frequency of handler interactions, and so may be a useful measure of handler behaviour.

The sociodemographic typology of sign languages classifies them based on the characteristics and configurations of their users. When considering homesign and sign languages in rural areas, this typology needs further refinement. Here, I present new concepts to enable this. The study is based on fieldwork with twelve deaf people in Western Highlands, Papua New Guinea, and review of studies worldwide. Sign language communities can be mapped as sign networks. Using this mapping, I propose a new typological category for languages with one central deaf user and many fluent hearing signers: nucleated network sign language. I use sign base analysis to determine lexical consistency between unconnected deaf signers in Western Highlands. The high level of consistency among largely unconnected deaf people is explained by a regional sign network connecting deaf and hearing signers. This research emphasises the role of both deaf and hearing signers in sign language emergence and maintenance. (Sign languages, social networks, sign networks, typology, homesign, rural sign languages, Papua New Guinea)*

COVID-19 has caused a major global pandemic and necessitated unprecedented public health restrictions in almost every country. Understanding risk factors for severe disease in hospitalised patients is critical as the pandemic progresses. This observational cohort study aimed to characterise the independent associations between the clinical outcomes of hospitalised patients and their demographics, comorbidities, blood tests and bedside observations. All patients admitted to Northwick Park Hospital, London, UK between 12 March and 15 April 2020 with COVID-19 were retrospectively identified. The primary outcome was death. Associations were explored using Cox proportional hazards modelling. The study included 981 patients. The mortality rate was 36.0%. Age (adjusted hazard ratio (aHR) 1.53), respiratory disease (aHR 1.37), immunosuppression (aHR 2.23), respiratory rate (aHR 1.28), hypoxia (aHR 1.36), Glasgow Coma Scale <15 (aHR 1.92), urea (aHR 2.67), alkaline phosphatase (aHR 2.53), C-reactive protein (aHR 1.15), lactate (aHR 2.67), platelet count (aHR 0.77) and infiltrates on chest radiograph (aHR 1.89) were all associated with mortality. These important data will aid clinical risk stratification and provide direction for further research.

Our preliminary investigation of the absorption and the photoluminescence response of selectively separated graphene quantum dots using centrifugation indicate that the photoluminescence is more sensitive to the size of the quantum dot than the absorption. We observed ∼143nm blueshift from 623nm to 480nm in the visible region of the photoluminescence with increasing successive centrifugation (decreasing size) and not in the corresponding absorption spectra in the visible region. However, for the first time, we observed a blueshift in the absorption spectra in the UV regions that is tentatively attributed to quantum confinement. Further detailed work is underway to confirm the blueshift in the absorption and correlate with deep UV photoluminescence and morphological quantification of the quantum dots size distribution using high resolution transmission electron microscope.

US Africa Command’s Disaster Preparedness Program (DPP), implemented by the Center for Disaster and Humanitarian Assistance Medicine, partnered with US Government agencies and international organizations to promote stability and security on the African continent by engaging with African Partner Nations’ (PN) civil and military authorities to improve disaster management capabilities. From 2008 to 2015, DPP conducted disaster preparedness and response programming with 17 PNs. DPP held a series of engagements with each, including workshops, strategic planning, developing preparedness and response plans, tabletop exercises, and prioritizing disaster management capability gaps identified through the engagements. DPP partners collected data for each PN to further capacity building efforts. Thus far, 9 countries have completed military pandemic plans, 10 have developed national pandemic influenza plans, 9 have developed military support to civil authorities plans, and 11 have developed disaster management strategic work plans. There have been 20 national exercises conducted since 2009. DPP was cited as key in implementation of Ebola response plans in PNs, facilitated development of disaster management agencies in DPP PNs, and trained nearly 800 individuals. DPP enhanced PNs’ ability to prepare and respond to crises, fostering relationships between international agencies, and improving civil-military coordination through both national and regional capacity building. (Disaster Med Public Health Preparedness. 2019;13:319–329)

Radio-glaciological parameters from the Moore’s Bay region of the Ross Ice Shelf, Antarctica, have been measured. The thickness of the ice shelf in Moore’s Bay was measured from reflection times of radio-frequency pulses propagating vertically through the shelf and reflecting from the ocean, and is found to be 576 ± 8 m. Introducing a baseline of 543 ± 7m between radio transmitter and receiver allowed the computation of the basal reflection coefficient, R, separately from englacial loss. The depth-averaged attenuation length of the ice column, 〈L〉 is shown to depend linearly on frequency. The best fit (95% confidence level) is 〈L(ν)〉= (460±20) − (180±40)ν m (20 dB km−1), for the frequencies ν = [0.100–0.850] GHz, assuming no reflection loss. The mean electric-field reflection coefficient is (1.7 dB reflection loss) across [0.100–0.850] GHz, and is used to correct the attenuation length. Finally, the reflected power rotated into the orthogonal antenna polarization is <5% below 0.400 GHz, compatible with air propagation. The results imply that Moore’s Bay serves as an appropriate medium for the ARIANNA high-energy neutrino detector.

Phytotoxicity of glyphosate (N-(phosphonomethyl) glycine), applied at 0, 0.56, 1.12, 1.68, 2.24 and 4.49 kg ai/ha to uniform, naturally growing quackgrass, [Agropyron repens (L.) Beauv.] plants, was studied with the electron microscope. Visible damage (yellowing of the leaves) to the plants was observed at the 2.24 and 4.49 kg ai/ha dosage rates within 72 hr. Similar damage became evident 120 hr after treatment at the 0.56 to 1.68 dosages. Leaf discs (1 mm in diameter) were harvested at 24, 48, 96, and 192 hr and prepared for electron microscopy by standard techniques. Cellular damage could be detected at all dosage rates as early as 24 hr after treatment. The type of damage observed was partial to complete disruption of the chloroplast envelope, and swelling of the rough endoplasmic reticulum (RER) with a subsequent formation of vesicles. With loss of integrity of the envelope, the chloroplast became completely disrupted with increased time. Other organelles within the cell were also destroyed.

Field studies were conducted in 2007 and 2008 near Lubbock and Lamesa, TX, to determine the effects of propazine alone and in combination with glyphosate applied PRE and POST on cotton growth, yield, and lint value (fiber quality). Propazine at 0.56, 0.84, and 1.12 kg ai ha−1 and in combination with glyphosate at 0.86 kg ae ha−1 was applied PRE, early POST, and mid-POST. Up to 11% injury was observed after propazine applied early POST and mid-POST at Lubbock in 1 of 2 yr, and up to 13% at all three application timings was observed at Lamesa in 1 of 2 yr. The greatest injury was observed 58 d after application following propazine at 1.12 kg ai ha−1 applied PRE; however, no injury was apparent 80 d after application. Cotton yield, lint values, and gross revenues were not affected by any treatment.

An assemblage of micromammals, recovered from the Holocene levels of a rockshelter at 2400 m in the montane forest of the Mau Escarpment, were examined with the goal of testing and contributing to prior reconstructions of paleoenvironments in the Central Rift Valley of Kenya. Species representation in the assemblage is consistent with a drying of the Rift Valley lakes in the middle Holocene and suggests a decrease in forest accompanied by expanding grasslands near the site. Changes in the abundance of grassland species suggests an increase in the frequency of fires, probably the result of pastoral burning. The body size of the root rat (Tachyoryctes splendens) decreases from the early Holocene to the middle Holocene, and this may indicate increasing aridity or increasing temperature. We compare measures of species diversity (number of taxa, species richness, and the Shannon diversity index) for both micromammals and macromammals since species diversity may change with paleoenvironmental change. The macromammals show no changes in species diversity that are assignable to paleoenvironmental change, while the micromammals show a trend toward decreasing diversity from the early to middle Holocene, and then show an increase in diversity during the peak of the middle Holocene dry phase, though sample size effects may be confounding the patterning.