Gold distribution in the Archean Tanzanian Craton: Evaluating the effects of intracrustal differentiation

This study evaluates the vertical distribution of gold in the continental crust. Implementing a recently published method by Pitcairn et al. (2006a) for the chromatographic separation of gold from acid-digested rocks using diisobutyl ketone (DIBK), followed by analysis using standard addition inductively coupled plasma mass spectrometry (ICP-MS), high- and low-grade metamorphic rocks of the Tanzanian Craton, representative of the lower and upper crust, respectively, are analyzed to determine the distribution of gold in the crust. Greenstone belt basalts have the highest gold concentrations (ave.=60 (+193/-19) ng/g), followed by greenstone belt andesites (ave.=1.4 (+3.6/-0.6) ng/g). The lowest concentrations are observed in granulite-facies lower-crustal xenoliths (ave.=0.4 (+1.0/-0.1) ng/g). Gold is incompatible in silicates and can partition into hydrothermal and/or magmatic fluid during high-grade metamorphic dehydration reactions or partial melting, particularly if sulfides break down during these processes. Rise of buoyant mobile phases may explain the depletion of gold in the lower crust

Feeding soy or fish meal to Alaskan reindeer (Rangifer tarandus tarandus) – effects on animal performance and meat quality

Fourteen reindeer (8 steers and 6 females) were used to compare the effects of two different reindeer diets (a feed mix based on barley, brome hay and soybean meal (SBM) or fishmeal (WFM) as protein source) on animal growth performance, feed conversion efficiency and ultimate meat quality. Samples from free-ranging reindeer (n=4; 2 steers and 2 females) on the Seward Peninsula were included to provide comparisons with the traditional reindeer meat produced in Alaska. No significant difference was observed in overall weight gain between the WFM and SBM animals or between females and steers; however, the feed conversion efficiency was significantly higher for the reindeer fed the WFM mix. Carcass dressing percentage from the SBM group was higher compared with the WFM animals. No differences were found in live weight, carcass characteristics, meat pH, temperature decline, shear force, meat color or cooking loss when comparing the treatment groups. The meat samples (M. longissimus) from the free-range group had the highest amount of omega-3 fatty acids and also the highest amount of polyunsaturated fatty acids (PUFA). Meat from the animals fed SBM was significantly higher in triglyceride content and lower in phospholipid content compared with the two other groups. No significant differences were found when the trained panel compared the sensory attributes of the meat. Off-flavor attributes related to “wild’ or “gamey” flavor was reported by consumers for samples from the WFM and free-range reindeer (15 and 24 per cent of the consumers, respectively). No “fish-related” flavor was reported. In conclusion, no negative effects in either animal performance or meat quality characteristics by using fish meal as opposed to soybean meal as a protein supplement in a milled reindeer diet were found.Abstract in Swedish / Sammandrag:Utfordring av ren med soja- eller fiskmjøl – effekter på tillväxt, foderutnyttjande och köttkvalitet I vår undersökning ingick 14 renar (8 kastrerade sarvar (härkar)och 6 vajor) för att jämföra effekter av två olika renfoder (baserade på korn, hö och soja- (SBM) eller fiskmjöl (WFM) som proteintillskott) med avseende på tillväxt, foderutnyttjande och köttkvalitet. Köttprover från naturbetande renar (n=4; 2 härkar och 2 vajor) från Seward Peninsula inkluderades i studien för att representera kvaliteten på traditionellt producerat renkött från Alaska. Inga signifikanta skillnader i tillväxt observerades, varken mellan SBM- och WFM-grupperna eller mellan härkar och vajor. Foderutnyttjandet var dock signifikant bättre hos WFM-renarna. Slaktutbytet var högst för renarna i SBM-gruppen, däremot rapporterades inga skillnader i levandevikt, slaktkroppsegenskaper, pH-värde och temperatur i ytterfilén, skärmotstånd, färg eller vattenhållande förmåga i köttet när de tre grupperna av renar jämfördes (SBM, WFM och naturbetande djur). Köttet från de naturbetande renarna hade det signifikant högsta innehållet av både omega-3-fettsyror och av fleromättade fettsyror. Kött från SBM-renarna hade det högsta innehållet av triglycerider och det lägsta innehållet av fosfolipider jämfört med de andra två grupperna. Den tränade smakpanelen kunde inte hitta några skillnader i sensoriska egenskaper hos köttet från renarna i de tre olika grupperna. I en konsumentundersökning rapporterades kommentarer om olika ”vilt-relaterade” bismaker i kött från naturbetande renar (24% av konsumenterna) och från WFM-gruppen (15% av konsumenterna), men inga ”fisk-liknande” bismaker i köttet kunde påvisas. Att byta ut sojamjöl mot fiskmjöl som proteintillskott i renfoder hade inga negativa effekter på renarnas tillväxt, foderutnyttjande eller på renköttets kvalitet

Photochemical oxidation of oxalate in Pu-238 process streams

For over forty years, NASA has relied on plutonium-238 in Radioisotope Thermoelectric Generator (RTG) units and Radioisotope Heater Units ( W s ) to provide power and heat for many space missions including Transit, Pioneer, Viking, Voyager, Galileo, Ulysses and Cassini. RHUs provide heat to keep key components warm in extremely cold environments found on planets, moons, or in deep space. RTGs convert heat generated from the radioactive decay of plutonium-238 into electricity using a themocouple, Plutonium-238 has proven to be an excellent heat source far deep space missions because of its high thermal power density, useful lifetime, minimal shielding requirements, and oxide stability

Treatment of electric vehicle battery waste in China: A review of existing policies

This paper reviews existing policies for supporting the treatment of electric vehicle (EV) battery waste in China, and identifies some of their major shortcomings that policy makers may like to consider while making policy decisions. The shortcomings of existing policies identified in this paper include: 1) no clear provisions for historical and orphan batteries; 2) no target for battery collection; 3) unclear definition of the scope of authority among various central and local agencies involved in the regulation of waste battery treatment; 4) unclear requirements for data auditing and verification for tracking the entire life cycle of EV batteries; 5) limited consideration of the challenges to ensure stakeholder cooperation; and 6) no explicit specification of the mechanisms for financing waste battery treatment. This paper also makes some practical policy suggestions for overcoming these shortcomings

Closing the Coverage Gaps: Reducing Health Insurance Disparities in Massachusetts

Massachusetts has been exemplary in developing health insurance coverage policies to cover its residents. By 2019, the state's uninsurance rate was 3.0 percent, the lowest rate in the nation, representing about 204,000 uninsured residents. While the state's overall uninsured rate at a given point in time is low, more than twice as many people - 503,000, or 7.3 percent of the population - experienced a gap in coverage over the previous twelve months. And importantly, not all groups benefit equally. People who are Black or Hispanic, or who have lower incomes, experience significantly higher rates of uninsurance than the state population overall. As a result, these groups are more likely to face access barriers and financial insecurity associated with being uninsured.The purpose of this report is to begin charting a course toward closing the coverage gaps in Massachusetts, with a particular focus on creating a more racially and ethnically equitable system of coverage. The report and accompanying infographics describe the people in Massachusetts without health insurance and the barriers to coverage they face, including affordability, administrative complexity, and immigration, language, and cultural barriers. It then proposes a menu of policy options that address the specific circumstances in Massachusetts. The proposed options are meant to inform a statewide conversation about the best approaches to closing the remaining coverage gaps in Massachusetts and removing structural barriers that result in racial and ethnic disparities in health insurance coverage

Robustness of potential biological removal to monitoring, environmental, and management uncertainties

Support for this project was provided by the Lenfest Ocean Program.The potential biological removal (PBR) formula used to determine a reference point for human-caused mortality of marine mammals in the United States has been shown to be robust to several sources of uncertainty. This study investigates the consequences of the quality of monitoring on PBR performance. It also explores stochastic and demographic uncertainty, catastrophic events, sublethal effects of interactions with fishing gear, and the situation of a marine mammal population subject to bycatch in two fisheries, only one of which is managed. Results are presented for two pinniped and two cetacean life histories. Bias in abundance estimates and whether there is a linear relationship between abundance estimates and true abundance most influence conservation performance. Catastrophic events and trends in natural mortality have larger effects than environmental stochasticity. Managing only one of two fisheries with significant bycatch leads, as expected, to a lower probability of achieving conservation management goals, and better outcomes would be achieved if bycatch in all fisheries were managed. The results are qualitatively the same for the four life histories, but estimates of the probability of population recovery differ.Publisher PDFPeer reviewe

Estimating bycatch mortality for marine mammals : concepts and best practices

Support for this project was provided by the Lenfest Ocean Program (Contract ID: #31008).Fisheries bycatch is the greatest current source of human-caused deaths of marine mammals worldwide, with severe impacts on the health and viability of many populations. Recent regulations enacted in the United States under the Fish and Fish Product Import Provisions of its Marine Mammal Protection Act require nations with fisheries exporting fish and fish products to the United States (hereafter, “export fisheries”) to have or establish marine mammal protection standards that are comparable in effectiveness to the standards for United States commercial fisheries. In many cases, this will require estimating marine mammal bycatch in those fisheries. Bycatch estimation is conceptually straightforward but can be difficult in practice, especially if resources (funding) are limiting or for fisheries consisting of many, small vessels with geographically-dispersed landing sites. This paper describes best practices for estimating bycatch mortality, which is an important ingredient of bycatch assessment and mitigation. We discuss a general bycatch estimator and how to obtain its requisite bycatch-rate and fisheries-effort data. Scientific observer programs provide the most robust bycatch estimates and consequently are discussed at length, including characteristics such as study design, data collection, statistical analysis, and common sources of estimation bias. We also discuss alternative approaches and data types, such as those based on self-reporting and electronic vessel-monitoring systems. This guide is intended to be useful to managers and scientists in countries having or establishing programs aimed at managing marine mammal bycatch, especially those conducting first-time assessments of fisheries impacts on marine mammal populations.Publisher PDFPeer reviewe

Estimating the abundance of marine mammal populations

Support for this project was provided by the Lenfest Ocean Program.Motivated by the need to estimate the abundance of marine mammal populations to inform conservation assessments, especially relating to fishery bycatch, this paper provides background on abundance estimation and reviews the various methods available for pinnipeds, cetaceans and sirenians. We first give an “entry-level” introduction to abundance estimation, including fundamental concepts and the importance of recognizing sources of bias and obtaining a measure of precision. Each of the primary methods available to estimate abundance of marine mammals is then described, including data collection and analysis, common challenges in implementation, and the assumptions made, violation of which can lead to bias. The main method for estimating pinniped abundance is extrapolation of counts of animals (pups or all-ages) on land or ice to the whole population. Cetacean and sirenian abundance is primarily estimated from transect surveys conducted from ships, small boats or aircraft. If individuals of a species can be recognized from natural markings, mark-recapture analysis of photo-identification data can be used to estimate the number of animals using the study area. Throughout, we cite example studies that illustrate the methods described. To estimate the abundance of a marine mammal population, key issues include: defining the population to be estimated, considering candidate methods based on strengths and weaknesses in relation to a range of logistical and practical issues, being aware of the resources required to collect and analyze the data, and understanding the assumptions made. We conclude with a discussion of some practical issues, given the various challenges that arise during implementation.Publisher PDFPeer reviewe