National Uranium Resource Evaluation Program: the Hydrogeochemical Stream Sediment Reconnaissance Program at LLNL

From early 1975 to mid 1979, Lawrence Livermore National Laboratory (LLNL) participated in the Hydrogeochemical Stream Sediment Reconnaissance (HSSR), part of the National Uranium Resource Evaluation (NURE) program sponsored by the Department of Energy (DOE). The Laboratory was initially responsible for collecting, analyzing, and evaluating sediment and water samples from approximately 200,000 sites in seven western states. Eventually, however, the NURE program redefined its sampling priorities, objectives, schedules, and budgets, with the increasingly obvious result that LLNL objectives and methodologies were not compatible with those of the NURE program office, and the LLNL geochemical studies were not relevant to the program goal. The LLNL portion of the HSSR program was consequently terminated, and all work was suspended by June 1979. Of the 38,000 sites sampled, 30,000 were analyzed by instrumental neutron activation analyses (INAA), delayed neutron counting (DNC), optical emission spectroscopy (OES), and automated chloride-sulfate analyses (SC). Data from about 13,000 sites have been formally reported. From each site, analyses were published of about 30 of the 60 elements observed. Uranium mineralization has been identified at several places which were previously not recognized as potential uranium source areas, and a number of other geochemical anomalies were discovered

THE RADIOCHEMISTRY OF THE TRANSCURIUM ELEMENTS

"Nuclear Science Series" on the National Research Council. Committee on Nuclear Science

A ‘criminal personas’ approach to countering criminal creativity

This paper describes a pilot study of a ‘criminal personas’ approach to countering criminal creativity. The value of the personas approach has been assessed by comparing the identification of criminal opportunity, through ‘traditional’ brainstorming and then through ‘criminal personas’ brainstorming The method involved brainstorm sessions with Computer Forensics Practitioners and with Product Designers, where they were required to generate criminal scenarios, select the most serious criminal opportunities, and propose means of countering them. The findings indicated that there was merit in further research in the development and application of the ‘criminal personas’ approach. The generation of criminal opportunity ideas and proposal of counter criminal solutions were both greater when the brainstorm approach involved the group responding through their given criminal personas

Nanoscale Mechanical Characterisation of Amyloid Fibrils Discovered in a Natural Adhesive

Using the atomic force microscope, we have investigated the nanoscale mechanical response of the attachment adhesive of the terrestrial alga Prasiola linearis (Prasiolales, Chlorophyta). We were able to locate and extend highly ordered mechanical structures directly from the natural adhesive matrix of the living plant. The in vivo mechanical response of the structured biopolymer often displayed the repetitive sawtooth force-extension characteristics of a material exhibiting high mechanical strength at the molecular level. Mechanical and histological evidence leads us to propose a mechanism for mechanical strength in our sample based on amyloid fibrils. These proteinaceous, pleated β-sheet complexes are usually associated with neurodegenerative diseases. However, we now conclude that the amyloid protein quaternary structures detected in our material should be considered as a possible generic mechanism for mechanical strength in natural adhesives

Toxicology and safety of the tincture of Operculina alata in patients with functional constipation

The tincture of Operculina alata, popularly known as "tincture of jalapa", is used in Northeast Brazil to treat constipation and encephalic vascular accident, but it has not yet been adequately tested for safety and efficacy. The aim of this study was to evaluate the toxicology and safety of the tincture of O. alata in patients with functional constipation. This was a double-blind, randomized, placebo-controlled clinical trial. The study consisted of three phases: pre-treatment, treatment and post-treatment, each phase with duration of seven days. Arterial pressure, heart rate, body weight, adverse events, hematological, metabolic, liver and kidney functions were monitored. Forty patients were randomized to receive tincture of O. alata and 43 patients to receive placebo. There were statistical differences in the clinical aspects between groups, but these changes were not considered clinically significant. Adverse events were considered not serious and of mild intensity, especially dizziness, headache, abdominal pain and nausea. This clinical trial confirmed the safety of the tincture of O. alata in the pharmaceutical form and dosage tested, allowing the product to be safely used in a larger population for the assessment of its clinical efficacy.A tintura de Operculina alata, popularmente conhecida como "tintura de jalapa", é usada no Nordeste do Brasil para tratar constipação intestinal e acidente vascular encefálico, mas sua eficácia e segurança ainda não foram confirmadas. O objetivo deste estudo foi avaliar a toxicologia e segurança da tintura de O. alata em pacientes com constipação intestinal funcional. Este foi um ensaio clínico duplo-cego, randomizado e controlado por placebo. O estudo consistiu de três fases: pré-tratamento, tratamento e pós-tratamento, cada fase com duração de sete dias. Foram monitorizados a pressão arterial, frequência cardíaca, peso corporal, eventos adversos e funções hematológica, metabólica, hepática e renal. Quarenta pacientes foram randomizados para receber tintura de O. alata e 43 pacientes para receber placebo. Houve diferenças estatísticas nos aspectos clínicos entre os grupos, contudo, estas mudanças não foram consideradas clinicamente significativas. Eventos adversos foram considerados não sérios e de leve intensidade, especialmente, cefaléia, tontura, dor abdominal e náusea. Este ensaio clínico confirmou a segurança da tintura de O. alata na forma farmacêutica e dosagem testada, permitindo que o produto seja testado em população maior para determinar sua eficácia clínica

The effects of secular calcium and magnesium concentration changes on the thermodynamics of seawater acid/base chemistry: Implications for Eocene and Cretaceous ocean carbon chemistry and buffering

Reconstructed changes in seawater calcium and magnesium concentration ([Ca2+], [Mg2+]) predictably affect the ocean’s acid/base and carbon chemistry. Yet inaccurate formulations of chemical equilibrium “constants” are currently in use to account for these changes. Here we develop an efficient implementation of the MIAMI Ionic InteractionModel to predict all chemical equilibrium constants required for carbon chemistry calculations under variable [Ca2+] and [Mg2+]. We investigate the impact of [Ca2+] and [Mg2+] on the relationships among the ocean’s pH,CO2, dissolved inorganic carbon (DIC), saturation state of CaCO3 (?), and buffer capacity. Increasing [Ca2+] and/or [Mg2+] enhances “ion pairing,” which increases seawater buffering by increasing the concentration ratio of total to “free” (uncomplexed) carbonate ion. An increase in [Ca2+], however, also causes a decline in carbonate ion to maintain a given ?, thereby overwhelming the ion pairing effect and decreasing seawater buffering. Given the reconstructions of Eocene [Ca2+] and [Mg2+] ([Ca2+] ~20mM; [Mg2+]~30mM), Eocene seawater would have required essentially the same DIC as today to simultaneously explain a similar-to-modern ? and the estimated Eocene atmospheric CO2 of ~1000 ppm. During the Cretaceous, at ~4 times modern [Ca2+], ocean buffering would have been at a minimum. Overall, during times of high seawater [Ca2+], CaCO3 saturation, pH, and atmospheric CO2 were more susceptible to perturbations of the global carbon cycle. For example, given both Eocene and Cretaceous seawater [Ca2+] and [Mg2+], a doubling of atmospheric CO2 would require less carbon addition to the ocean/atmosphere system than under modern seawater composition. Moreover, increasing seawater buffering since the Cretaceous may have been a driver of evolution by raising energetic demands of biologically controlled calcification and CO2 concentration mechanisms that aid photosynthesis