The evaluation of brine prospects and the requirement for modifications to filing standards

The recent increase in demand for lithium has led to the development of new brine prospects, particularly in the Central Andes. The brines are hosted in closed basin aquifers of two types: mature, halite dominant, and immature, clastic dominant. The estimate of elemental resources in these salars depends on a detailed knowledge of aquifer geometry, porosity, and brine grade. The geometry of the aquifers can be evaluated by classical geophysical and drilling techniques, but because the resource is a fluid, with the attendant problems of in-aquifer mixing and reorganization, existing codes for filing resource and reserve estimates need modification. Total porosity is relatively straightforward to measure, but effective porosity and specific yield, which are required to estimate the resource, are more difficult. Recovery factors are low compared with most metalliferous and industrial mineral deposits due to reliance on pumping of the brine from wells for extraction. These and related issues lead us to believe that modifications to the existing standards for reporting mineral resources and reserves are required for these prospects

Sensorized Tools for Haptic Force Feedback in Computer Assisted Surgery

Structural engineerin

Climate oscillations, glacial refugia, and dispersal ability: factors influencing the genetic structure of the least salmonfly, Pteronarcella badia (Plecoptera), in Western North America

Background: Phylogeographic studies of aquatic insects provide valuable insights into mechanisms that shape the genetic structure of communities, yet studies that include broad geographic areas are uncommon for this group. We conducted a broad scale phylogeographic analysis of the least salmonfly Pteronarcella badia (Plecoptera) across western North America. We tested hypotheses related to mode of dispersal and the influence of historic climate oscillations on population genetic structure. In order to generate a larger mitochondrial data set, we used 454 sequencing to reconstruct the complete mitochondrial genome in the early stages of the project. Results: Our analysis revealed high levels of population structure with several deeply divergent clades present across the sample area. Evidence from five mitochondrial genes and one nuclear locus identified a potentially cryptic lineage in the Pacific Northwest. Gene flow estimates and geographic clade distributions suggest that overland flight during the winged adult stage is an important dispersal mechanism for this taxon. We found evidence of multiple glacial refugia across the species distribution and signs of secondary contact within and among major clades. Conclusions: This study provides a basis for future studies of aquatic insect phylogeography at the inter-basin scale in western North America. Our findings add to an understanding of the role of historical climate isolations in shaping assemblages of aquatic insects in this region. We identified several geographic areas that may have historical importance for other aquatic organisms with similar distributions and dispersal strategies as P. badia. This work adds to the ever-growing list of studies that highlight the potential of next-generation DNA sequencing in a phylogenetic context to improve molecular data sets from understudied groups

Farm Level Comparison of H.R. 2646 and S. 1731

The provisions in the House (H.R. 2646) and Senate (S. 1731) farm bills are analyzed with respect to their impacts on 94 representative crop, livestock, and dairy farms. The analysis incorporates both historical price and production risk for the farms so the “safety net” aspects of the bills can be compared. Representative crop livestock and dairy farms for major production regions across the county are analyzed. Information to describe and simulate these farms comes from a panel of farmers in each local area. The farm panels are reconvened frequently to update their farm’s data. The representative farm data base has been used for policy analysis for more than 15 years. The simulation model used for the analysis was developed by AFPC scientists.Agribusiness, Agricultural and Food Policy,

Automated Text Messaging With Patients in Department of Veterans Affairs Specialty Clinics: Cluster Randomized Trial

BACKGROUND: Acceptability of mobile phone text messaging as a means of asynchronous communication between health care systems and patients is growing. The US Department of Veterans Affairs (VA) has adopted an automated texting system (aTS) for national rollout. The aTS allows providers to develop clinical texting protocols to promote patient self-management and allows clinical teams to monitor patient progress between in-person visits. Texting-supported hepatitis C virus (HCV) treatment has not been previously tested. OBJECTIVE: Guided by the Practical, Robust Implementation and Sustainability Model (PRISM), we developed an aTS HCV protocol and conducted a mixed methods, hybrid type 2 effectiveness implementation study comparing two programs supporting implementation of the aTS HCV protocol for medication adherence in patients with HCV. METHODS: Seven VA HCV specialty clinics were randomized to usual aTS implementation versus an augmented implementation facilitation program. Implementation process measures included facilitation metrics, usability, and usefulness. Implementation outcomes included provider and patient use of the aTS HCV protocol, and effectiveness outcomes included medication adherence, health perceptions and behaviors, and sustained virologic response (SVR). RESULTS: Across the seven randomized clinics, there were 293 facilitation events using a core set of nine implementation strategies (157 events in augmented implementation facilitation, 136 events in usual implementation). Providers found the aTS appropriate with high potential for scale-up but not without difficulties in startup, patient selection and recruitment, and clinic workflow integration. Patients largely found the aTS easy to use and helpful; however, low perceived need for self-management support contributed to high declination. Reach and use was modest with 197 patients approached, 71 (36%) enrolled, 50 (25%) authenticated, and 32 (16%) using the aTS. In augmented implementation facilitation clinics, more patients actively used the aTS HCV protocol compared with usual clinic patients (20% vs 12%). Patients who texted reported lower distress about failing HCV treatment (13/15, 87%, vs 8/15, 53%; P=.05) and better adherence to HCV medication (11/15, 73%, reporting excellent adherence vs 6/15, 40%; P=.06), although SVR did not differ by group. CONCLUSIONS: The aTS is a promising intervention for improving patient self-management; however, augmented approaches to implementation may be needed to support clinician buy-in and patient engagement. Considering the behavioral, social, organizational, and technical scale-up challenges that we documented, successful and sustained implementation of the aTS may require implementation strategies that operate at the clinic, provider, and patient levels. TRIAL REGISTRATION: Retrospectively registered at ClinicalTrials.gov NCT03898349; https://clinicaltrials.gov/ct2/show/NCT03898349. Jessica Lipschitz, Beth Ann Petrakis, Chris Gillespie, D Keith McInnes

Racial disparities in healthcare provider advice to quit smoking

African-American/Black smokers are less likely than White smokers to be told to quit smoking by healthcare providers. This preliminary study examined the predictors of being told to quit separately by race for the first time to potentially highlight the source of this racial disparity. A random, household sample of 1670 Black and White adults from a southeastern county of the United States completed a brief survey on their demographics, smoking, access to healthcare, health status, and receipt of healthcare provider advice to quit smoking. Analyses are based on the 512 Black and White smokers in that sample. The logistic regression for all smokers revealed that after controlling for demographic, healthcare, and health status variables, White smokers were 2.39 times more likely than Black smokers to have ever been told to quit smoking. The regression for Black smokers re- vealed that women and older people were more likely to be told to quit, and that healthcare and health status did not contribute. In the regression for White smokers, no predictor was statistically significant. These findings suggest that one possible reason that African-Americans receive cessation advice less often than Whites is that such advice varies with their age and gender, whereas for Whites this is not the case

Patient Use of Electronic Prescription Refill and Secure Messaging and Its Association With Undetectable HIV Viral Load: A Retrospective Cohort Study

BACKGROUND: Electronic personal health records (PHRs) can support patient self-management of chronic conditions. Managing human immunodeficiency virus (HIV) viral load, through taking antiretroviral therapy (ART) is crucial to long term survival of persons with HIV. Many persons with HIV have difficulty adhering to their ART over long periods of time. PHRs contribute to chronic disease self-care and may help persons with HIV remain adherent to ART. Proportionally veterans with HIV are among the most active users of the US Department of Veterans Affairs (VA) PHR, called My HealtheVet. Little is known about whether the use of the PHR is associated with improved HIV outcomes in this population. OBJECTIVE: The objective of this study was to investigate whether there are associations between the use of PHR tools (electronic prescription refill and secure messaging [SM] with providers) and HIV viral load in US veterans. METHODS: We conducted a retrospective cohort study using data from the VA\u27s electronic health record (EHR) and the PHR. We identified veterans in VA care from 2009-2012 who had HIV and who used the PHR. We examined which ones had achieved the positive outcome of suppressed HIV viral load, and whether achievement of this outcome was associated with electronic prescription refill or SM. From 18,913 veterans with HIV, there were 3374 who both had a detectable viral load in 2009 and who had had a follow-up viral load test in 2012. To assess relationships between electronic prescription refill and viral control, and SM and viral control, we fit a series of multivariable generalized estimating equation models, accounting for clustering in VA facilities. We adjusted for patient demographic and clinical characteristics associated with portal use. In the initial models, the predictor variables were included in dichotomous format. Subsequently, to evaluate a potential dose-effect, the predictor variables were included as ordinal variables. RESULTS: Among our sample of 3374 veterans with HIV who received VA care from 2009-2012, those who had transitioned from detectable HIV viral load in 2009 to undetectable viral load in 2012 tended to be older (P=.004), more likely to be white (P\u3c.001), and less likely to have a substance use disorder, problem alcohol use, or psychosis (P=.006, P=.03, P=.004, respectively). There was a statistically significant positive association between use of electronic prescription refill and change in HIV viral load status from 2009-2012, from detectable to undetectable (OR 1.36, CI 1.11-1.66). There was a similar association between SM use and viral load status, but without achieving statistical significance (OR 1.28, CI 0.89-1.85). Analyses did not demonstrate a dose-response of prescription refill or SM use for change in viral load. CONCLUSIONS: PHR use, specifically use of electronic prescription refill, was associated with greater control of HIV. Additional studies are needed to understand the mechanisms by which this may be occurring

Polymer sensorised microgrippers using SMA actuation

Abstract-In this paper a polymer sensorised microgripping tool for micromanipulation is presented. The gripper structure is made by moulding of polyurethane in silicon moulds by the technique of Shape Deposition Manufacturing (SDM), in which the force sensing elements and part of the actuator (in this case, microstrain gauges and SMA (Shape Memory Alloy) wire, respectively) are embedded into the microgripper in one process step. The actuation principle for the microgripper is an SMA wire. The advantages of the fabrication process are low cost and manufacture cycle time. This paper details the technique for fabrication of the microgripper to produce prototypes. These prototypes were then tested and characterised in terms of force output, hysteresis and repeatability. A further miniaturised unsensorised microgripper based on the same actuation principle and fabrication process (but less than half the size) was fabricated to demonstrate the possibility of further downscaling

Xanthine oxidase inhibition for the improvement of long-term outcomes following ischaemic stroke and transient ischaemic attack (XILO-FIST) - Protocol for a randomised double blind placebo-controlled clinical trial

Background: Allopurinol, a xanthine oxidase inhibitor, reduced progression of carotid-intima media thickness and lowered blood pressure in a small clinical trial in people with ischaemic stroke. Xanthine oxidase inhibition for improvement of long-term outcomes following ischaemic stroke and transient ischaemic attack (XILO-FIST) aims to assess the effect of allopurinol treatment on white matter hyperintensity progression and blood pressure after stroke. This paper describes the XILO-FIST protocol. Methods: XILO-FIST is a multicentre randomised double-blind, placebo-controlled, parallel group clinical trial funded by the British Heart Foundation and the Stroke Association. The trial has been adopted by the Scottish Stroke Research Network and the UK Clinical Research Network. The trial is registered in clinicaltrials.gov (registration number NCT02122718). XILO-FIST will randomise 464 participants, aged greater than 50 years, with ischaemic stroke within the past month, on a 1:1 basis, to two years treatment with allopurinol 300 mg twice daily or placebo. Participants will undergo brain magnetic resonance imaging, cognitive assessment, ambulatory blood pressure monitoring and blood sampling at baseline and after two years treatment. The primary outcome will be white matter hyperintensity progression, measured using the Rotterdam progression scale. Secondary outcomes will include change in white matter hyperintensity volume, mean day-time systolic blood pressure and measures of cognitive function. Up to 100 will undergo additional cardiac magnetic resonance imaging in a sub-study of left ventricular mass. Discussion: If white matter hyperintensity progression is reduced, allopurinol could be an effective preventative treatment for patients with ischaemic stroke and clinical endpoint studies would be needed. If allopurinol reduces blood pressure after stroke, then it could be used to help patients reach blood pressure targets

Active Amplification of the Terrestrial Albedo to Mitigate Climate Change: An Exploratory Study

This study explores the potential to enhance the reflectance of solar insolation by the human settlement and grassland components of the Earth's terrestrial surface as a climate change mitigation measure. Preliminary estimates derived using a static radiative transfer model indicate that such efforts could amplify the planetary albedo enough to offset the current global annual average level of radiative forcing caused by anthropogenic greenhouse gases by as much as 30 percent or 0.76 W/m2. Terrestrial albedo amplification may thus extend, by about 25 years, the time available to advance the development and use of low-emission energy conversion technologies which ultimately remain essential to mitigate long-term climate change. However, additional study is needed to confirm the estimates reported here and to assess the economic and environmental impacts of active land-surface albedo amplification as a climate change mitigation measure.Comment: 21 pages, 3 figures. In press with Mitigation and Adaptation Strategies for Global Change, Springer, N