Struvite stones

Struvite, a crystalline substance first identified in the 18th century, is composed of magnesium ammonium phosphate (MgNH4PO4 · 6H2O). Ulex, a Swedish geologist, is generally credited with introduction of the term struvite in 1845; he coined the geological expression “struvite” in honor of H. C. G. von Stuve, a Russian diplomat and naturalist (1772–1851) [1]. Von Stuve had published one of the earliest scholarly geological works in 1807 entitled “Mineralogical Memoirs”.Struvite urinary stones have also been referred to as “infection stones” and “triple phosphate” stones. The term triple phosphate stems from early chemical analyses of the stones which demonstrated the presence of calcium, magnesium, ammonium, and phosphate (i.e., three cations and one anion). Carbonate ions were also commonly identified; they were assumed to be associated with calcium as calcium carbonate (CaCO3). Modern crystallographic analyses have shown that human “struvite” stones are a mixture of struvite (MgNH4PO4·6H2O) and carbonate-apatite (Ca10[PO4]6-CO3). Calcite (CaCO3) is extremely rare (we have found one calcite stone in 20,000 stone analyses) and may be an artifact. In some stones, struvite may be more abundant, whereas in other stones apatite may predominate. There is good evidence (to be reviewed) to link the formation of struvite and carbonate-apatite stones to urinary infection. For the purpose of this review, infection-induced stones are synonymous with struvite and carbonate-apatite

International Trade In Dairy Products: Processors Market Power

In the past two decades there has been a considerable amount of research conducted into the international price and trade effects of government intervention in the dairy industries of several countries. Recently, the conclusions of those studies have been questioned owing to the rising concentration in the processor sector. Since processors are increasingly multinational in nature and a few of them are operating around the globe, there is a possibility that the processors will influence both the farm and retail prices through their having market power.Multinational, Processor market power, Dairy products, International Relations/Trade,

Variations in plant forage quality in the range of the Porcupine caribou herd

Understanding potential impacts of vegetation change on caribou energetics requires information on variations in forage quality among different plant types and over time. We synthesized data on forage quality (nitrogen, neutral detergent fiber and dry matter digestibility) for 10 plant growth forms from existing scientific literature and from field research in the Arctic National Wildlife Refuge, Alaska. These data describe forage quality of plant species in habitats found within the summer and winter range of the Porcupine caribou herd in northwestern Canada and northern Alaska, U.S.A. We compared mean levels of summer forage quality among growth forms and, where possible, estimated seasonal changes in forage quality. Preferred forage groups (deciduous shrubs, forbs, and cottongrass flowers) had higher nitrogen and digestibility, and lower fiber content, than other growth forms. Nitrogen concentration in green biomass peaked at the onset of the growing season in forbs and deciduous shrubs, whereas graminoids reached peak nitrogen concentrations approximately 15-30 days after growth initiation. In vitro dry matter digestibility (IVDMD) and concentration of neutral detergent fiber (NDF) of green biomass differed among growth forms, but did not show strong seasonal changes. IVDMD and NDF concentrations were correlated with nitrogen concentrations in studies that had paired sampling

The Dormancy Dilemma: Quiescence versus Balanced Proliferation

Metastatic dissemination with subsequent clinical outgrowth leads to the greatest part of morbidity and mortality from most solid tumors. Even more daunting is that many of these metastatic deposits silently lie undetected, recurring years to decades after primary tumor extirpation by surgery or radiation (termed metastatic dormancy). As primary tumors are frequently curable, a critical focus now turns to preventing the lethal emergence from metastatic dormancy. Current carcinoma treatments include adjuvant therapy intended to kill the cryptic metastatic tumor cells. Because such standard therapies mainly kill cycling cells, this approach carries an implicit assumption that metastatic cells are in the mitogenic cycle. Thus, the pivotal question arises as to whether clinically occult micrometastases survive in a state of balanced proliferation and death, or whether these cells undergo at least long periods of quiescence marked by cell-cycle arrest. The treatment implications are thus obvious—if the carcinoma cells are cycling then therapies should target cycling cells, whereas if cells are quiescent then therapies should either maintain dormancy or be toxic to dormant cells. Because this distinction is paramount to rational therapeutic development and administration, we investigated whether quiescence or balanced proliferation is the most likely etiology underlying metastatic dormancy. We recently published a computer simulation study that determined that balanced proliferation is not the likely driving force and that quiescence most likely participates in metastatic dormancy. As such, a greater emphasis on developing diagnostics and therapeutics for quiescent carcinomas is needed.National Institutes of Health (U.S.). National Center for Advancing Translational Sciences (Grant UH2TR000496

An Additional Potential Factor for Kidney Stone Formation during Space Flights: Calcifying Nanoparticles (Nanobacteria): A Case Report

Spaceflight-induced microgravity appears to be a risk factor for the development of urinary calculi due to skeletal calcium liberation and other undefined factors, resulting in stone disease in crewmembers during and after spaceflight. Calcifying nanoparticles, or nanobacteria, reproduce at a more rapid rate in simulated microgravity conditions and create external shells of calcium phosphate in the form of apatite. The questions arises whether calcifying nanoparticles are niduses for calculi and contribute to the development of clinical stone disease in humans, who possess environmental factors predisposing to the development of urinary calculi and potentially impaired immunological defenses during spaceflight. A case of a urinary calculus passed from an astronaut post-flight with morphological characteristics of calcifying nanoparticles and staining positive for a calcifying nanoparticle unique antigen, is presented

Self-rated health in rural Appalachia: health perceptions are incongruent with health status and health behaviors

<p>Abstract</p> <p>Background</p> <p>Appalachia is characterized by poor health behaviors, poor health status, and health disparities. Recent interventions have not demonstrated much success in improving health status or reducing health disparities in the Appalachian region. Since one's perception of personal health precedes his or her health behaviors, the purpose of this project was to evaluate the self-rated health of Appalachian adults in relation to objective health status and current health behaviors.</p> <p>Methods</p> <p>Appalachian adults (n = 1,576) were surveyed regarding health behaviors - soda consumer (drink ≥ 355 ml/d), or non-consumer (drink < 355 ml/d), fast food consumer (eating fast food ≥ 3 times/wk) or healthy food consumer (eating fast food < 3 times/wk), smoking (smoker or non-smoker), exercise (exerciser > 30 min > 1 d/wk) and sedentary (exercise < 30 min 1 d/wk), blood pressure medication (yes, no), and self-rated health. Blood pressure was measured through auscultation and serum cholesterol measured via needle prick. Weight status was based on BMI: normal weight (NW ≥ 18.5 and < 25.0), overweight (OW ≥ 25.0 and < 30.0), and obese (OB ≥ 30.0). Jaccard Binary Similarity coefficients, odds ratios, chi-square, and prevalence ratios were calculated to evaluate the relationships among self-rated health, objective health status, and health behaviors. Significance was set at p < 0.05.</p> <p>Results</p> <p>Respondents reported being healthy, while being sedentary (65%), hypertensive (76%), overweight (73%), or hyperlipidemic (79%). Between 57% and 66% of the respondents who considered themselves healthy had at least two disease conditions or poor health behaviors. Jaccard Binary Similarity coefficients and odds ratios showed the probability of reporting being healthy when having a disease condition or poor health behavior was high.</p> <p>Conclusions</p> <p>The association between self-rated health and poor health indicators in Appalachian adults is distorted. The public health challenge is to formulate messages and programs about health and health needs which take into account the current distortion about health in Appalachia and the cultural context in which this distortion was shaped.</p

Evaluation of Extent and Bioavailability of Chromium Contamination Near an Abandoned Strip Mine

Chromium is a potentially toxic element to plants and animals commonly associated with serpentine and anthropogenic sources. An abandoned Cr strip-mine at US National Guard Camp SLO, CA containing serpentinitic parent material was tested for total and bioavailable Cr in the soil and overlying vegetation via US EPA Methods 3050a (Total Cr) and 1311 (Total Characteristic Leaching Procedure, TCLP) (US EPA, 1995), respectively. The analysis of total and bioavailable Cr was used to assess the risk of nearby surface and groundwater contamination and to evaluate the site’s need for remediation. In addition, trends in soil Cr levels with respect to slope position and sampling transect were identified. Total and most bioavailable Cr concentrations in plants were below the method detection limits (TotalMDL = 0.12 mg L-1; TCLPMDL = 0.04 mg L-1), suggesting the Cr was immobile and not bioavailable. The average total Cr level was 403.5 +/- 177.6 mg kg-1, significantly below the background total Cr level of 829.4 +/- 213.6 mg kg-1. Based on Chromium’s immobility, and its low levels in the site relative to background concentrations, remediation practices were not recommended. No significant trends were observed in total soil Cr levels along any transect or between sampled slope positions. The information gained from this was used by Camp SLO officers to assess the threat of Cr mobility and bioavailability in the soils at this site, as well as in nearby waterways and ground water

Propulsion Control Technology Development Needs to Address NASA Aeronautics Research Mission Goals for Thrusts 3a and 4

The Commercial Aero-Propulsion Control Working Group (CAPCWG), consisting of propulsion control technology leads from The Boeing Company, GE Aviation, Honeywell, Pratt & Whitney, Rolls-Royce, and NASA (National Aeronautics and Space Administration) Glenn Research Center, has been working together over the past year to identify propulsion control technology areas of common interest that we believe are critical to achieving the challenging NASA Aeronautics Research goals for Thrust 3a: Ultra-Efficient Commercial Vehicles - Subsonic Transports, and Thrust 4: Transition to Alternative Propulsion and Energy. This paper describes the various propulsion control technology development areas identified by CAPCWG as most critical for NASA to invest in. For Thrust 3a these are: i) Integrated On-Board Model Based Engine Control and Health Management; ii) Flexible and Modular Networked Control Hardware and Software Architecture; iii) Intelligent Air/Fuel Control for Low Emissions Combustion; and iv) Active Clearance Control. For Thrust 4a, the focus is on Hybrid Electric Propulsion (HEP) for single aisle commercial aircraft. The specific technology development areas include: i) Integrated Power and Propulsion System Dynamic Modeling for Control; ii) Control Architectures for HEP; iii) HEP Control Verification and Validation; and iv) Engine/Airplane Control Integration. For each of the technology areas, the discussion includes: problem to be solved and how it relates to NASA goals, and the challenges to be addressed in reducing risk

The Tropical Forest and Fire Emissions Experiment: Overview and Airborne Fire Emission Factor Measurements

The Tropical Forest and Fire Emissions Experiment (TROFFEE) used laboratory measurements followed by airborne and ground based field campaigns during the 2004 Amazon dry season to quantify the emissions from pristine tropical forest and several plantations as well as the emissions, fuel consumption, and fire ecology of tropical deforestation fires. The airborne campaign used an Embraer 110B aircraft outfitted with whole air sampling in canisters, mass-calibrated nephelometry, ozone by UV absorbance, Fourier transform infrared spectroscopy (FTIR), and proton-transfer mass spectrometry (PTR-MS) to measure PM(10), O(3), CO(2), CO, NO, NO(2), HONO, HCN, NH(3), OCS, DMS, CH(4), and up to 48 non-methane organic compounds (NMOC). The Brazilian smoke/haze layers extended to 2 - 3 km altitude, which is much lower than the 5 - 6 km observed at the same latitude, time of year, and local time in Africa in 2000. Emission factors (EF) were computed for the 19 tropical deforestation fires sampled and they largely compare well to previous work. However, the TROFFEE EF are mostly based on a much larger number of samples than previously available and they also include results for significant emissions not previously reported such as: nitrous acid, acrylonitrile, pyrrole, methylvinylketone, methacrolein, crotonaldehyde, methylethylketone, methylpropanal, \u27\u27 acetol plus methylacetate,\u27\u27 furaldehydes, dimethylsulfide, and C(1)-C(4) alkyl nitrates. Thus, we recommend these EF for all tropical deforestation fires. The NMOC emissions were similar to 80% reactive, oxygenated volatile organic compounds (OVOC). Our EF for PM(10) (17.8 +/- 4 g/kg) is similar to 25% higher than previously reported for tropical forest fires and may reflect a trend towards, and sampling of, larger fires than in earlier studies. A large fraction of the total burning for 2004 likely occurred during a two-week period of very low humidity. The combined output of these fires created a massive \u27\u27 mega-plume \u27\u27 \u3e 500 km across that we sampled on 8 September. The mega-plume contained high PM(10) and 10 - 50 ppbv of many reactive species such as O(3), NH(3), NO(2), CH(3)OH, and organic acids. This is an intense and globally important chemical processing environment that is still poorly understood. The mega-plume or \u27\u27 white ocean \u27\u27 of smoke covered a large area in Brazil, Bolivia, and Paraguay for about one month. The smoke was transported \u3e 2000 km to the southeast while remaining concentrated enough to cause a 3 - 4-fold increase in aerosol loading in the S (a) over tildeo Paulo area for several days