Determinations of Sodium Chloride Equivalents by Osmometry

The vapor pressure osmometer was used to calculate the sodium chloride equivalents of several compounds. These values were compared with published values and in some cases, considerable variation was seen. The osmolality was determined for iso-osmotic drug solutions mixed in different ratios with iso-osmotic saline or sorbitol. The drugs investigated included atropine sulfate, te-tracycline hydrochloride, homatropine hydrobromide, pilocarpine nitrate, amphetamine sulfate and bromodiphenhydramine hydrochloride. The results of these studies showed that colligative properties of multicomponent aqueous solutions are often non-additive in manner. The changing osmolality suggests that ion-ion or ion-molecule forces are occurring and when osmolality increases, so does the number of particles in solution.     

A clinical evaluation of transdermal therapeutic system fentanyl for the treatment of cancer pain

PROBLEM: Circulating inflammatory cytokines have been implicated in the pathogenesis of preeclampsia. To test this hypothesis, we measured plasma levels of immunoreactive tumor necrosis factor (TNF)-alpha and -beta, interleukin (IL)-1 alpha and -beta, and IL-6 and -10 in women with preeclampsia, in women with transient gestational hypertension, and throughout normal pregnancy. METHOD OF STUDY: Enzyme-linked immunosorbent assays were used and subjected to extensive validation studies. RESULTS: The median concentration of plasma TNF-alpha was increased by twofold in women with preeclampsia compared with that in normal third-trimester pregnancy (P < 0.001) and in women with gestational hypertension (P < 0.04). The median concentration of plasma IL-6 was increased by threefold in women with preeclampsia compared with that in normal third-trimester pregnancy (P < 0.001) and increased twofold compared with that in women with gestational hypertension (P < 0.1). There were no significant differences observed in the levels of plasma IL-1 beta and IL-10 between the preeclamptic and other subject groups. The level of IL-1 beta, but not the levels of IL-10, TNF-alpha, or IL-6, was significantly changed during normal pregnancy compared with the nonpregnant condition manifesting an overall decline (P < 0.04). TNF-beta and IL-1 alpha were not detected in any samples, possibly because of the low sensitivity of these particular immunoassays. CONCLUSION: Elevated levels of TNF-alpha and IL-6 may contribute to the putative endothelial dysfunction of preeclampsia.     

Disclosing HIV seropositivity to significant others

OBJECTIVES: To examine gay men's patterns of self-disclosure of HIV seropositivity to friends, lovers, relatives and colleagues; to assess the effects of disclosure; and to identify reasons for not disclosing to particular individuals. DESIGN: Longitudinal questionnaire survey of gay men. METHODS: A total of 163 HIV-positive men participating in the AIDS Behavioral Research Project, a longitudinal study of San Francisco gay men, completed questionnaires about their self-disclosure patterns, health status, and psychological well-being. RESULTS: HIV-positive men were most likely to disclose their status to lovers and closest gay friends. Asymptomatic men were less likely to disclose to relatives and colleagues than symptomatic men. Friends and lovers were rated as responding more helpfully than relatives and colleagues. Men who perceived their significant others as responding more helpfully were less depressed and anxious currently and 1 year later. A variety of reasons were given for not disclosing, including not wanting to worry others, fear of discrimination, fear of disrupting relationships, and emotional self-protection. CONCLUSION: While disclosure can have advantages for both HIV-positive individuals and their significant others, HIV-positive individuals must be assured that the benefits of doing so will outweigh the potential costs.     

High temperature mechanical behavior of porous ceria and ceria-based solid-oxide fuel cells

Multiple environment mechanical testing of solid-oxide fuel cells (SOFCs) and SOFC materials is critical to ensure appropriate compressive sealing in stack designs. Establishing the effects of temperature, environment, and porosity on the flexural strength of ceria-based SOFCs is a significant step toward practical deployment of the technology. This article presents research into these properties by use of a temperature and atmosphere controlled 3-point bend fixture capable of reaching Intermediate Temperature (IT)-SOFC operating conditions (650°C). Gadolinium-doped ceria (GDC) samples with varying porosity and pore geometry were tested and it was determined that more spherical porosity contributed to improved flexural strength as compared with higher aspect ratio porosity. A linear strengthening effect was also observed with increasing temperature from ambient to 650°C for GDC-based anode support layers and half-cell samples. Scanning electron microscopy was performed on fracture surfaces to identify fracture modes and to examine internal pore structures. Directionality of the applied stress with respect to the layered microstructure was found to have no measurable impact on mechanical properties in air, but orientation had a significant impact on strength of cells with reduced anodes. Additionally, with the support of thermogravimetric analysis, it was determined that after reduction, exposure to oxygen below 100°C does not influence mechanical properties of the cells.     

Liver and thymus lipid composition in AKR mice with and without lymphomas

Lipid composition of liver and thymus in controls, early stage lymphoma, and advanced stage lymphoma-bearing AKR mice was studied. There was a significant decrease in the liver total lipid content in mice with advanced lymphoma, whereas in the early stages, no quantitative change was seen. In livers of mice with advanced stage lymphoma, there was a significant decrease in the nonpolar fraction. The decrease was in triglyceride, whereas the cholesterol fractions were relatively increased though highly variable. There was an increase in the polar lipid/nonpolar lipid ratio in the advanced lymphoma livers and a very large increase in the polar lipid/triglyceride ratio, indicating that the decrease in total lipid in these livers was largely in the triglyceride fraction. Similar changes were seen in the thymus, in which the lipid composition reflected the transformation from normal to malignant cells.     

Toward Low-Cost,High-Energy Density,and High-Power Density Lithium-Ion Batteries

Reducing cost and increasing energy density are two barriers for widespread application of lithium-ion batteries in electric vehicles. Although the cost of electric vehicle batteries has been reduced by ~70% from 2008 to 2015, the current battery pack cost ($268/kWh in 2015) is still >2 times what the USABC targets ($125/kWh). Even though many advancements in cell chemistry have been realized since the lithium-ion battery was first commercialized in 1991, few major breakthroughs have occurred in the past decade. Therefore, future cost reduction will rely on cell manufacturing and broader market acceptance. This article discusses three major aspects for cost reduction: (1) quality control to minimize scrap rate in cell manufacturing; (2) novel electrode processing and engineering to reduce processing cost and increase energy density and throughputs; and (3) material development and optimization for lithium-ion batteries with high-energy density. Insights on increasing energy and power densities of lithium-ion batteries are also addressed.     

Iron solubility related to particle sulfur content in source emission and ambient fine particles

The chemical factors influencing iron solubility (soluble iron/total iron) were investigated in source emission (e.g., biomass burning, coal fly ash, mineral dust, and mobile exhaust) and ambient (Atlanta, GA) fine particles (PM2.5). Chemical properties (speciation and mixing state) of iron-containing particles were characterized using X-ray absorption near edge structure (XANES) spectroscopy and micro-X-ray fluorescence measurements. Bulk iron solubility (soluble iron/total iron) of the samples was quantified by leaching experiments. Major differences were observed in iron solubility in source emission samples, ranging from low solubility (<1%, mineral dust and coal fly ash) up to 75% (mobile exhaust and biomass burning emissions). Differences in iron solubility did not correspond to silicon content or Fe(II) content. However, source emission and ambient samples with high iron solubility corresponded to the sulfur content observed in single particles. A similar correspondence between bulk iron solubility and bulk sulfate content in a series of Atlanta PM2.5 fine particle samples (N = 358) further supported this trend. In addition, results of linear combination fitting experiments show the presence of iron sulfates in several high iron solubility source emission and ambient PM2.5 samples. These results suggest that the sulfate content (related to the presence of iron sulfates and/or acid-processing mechanisms by H(2)SO(4)) of iron-containing particles is an important proxy for iron solubility.     

PCDD/F,PCB, HxCBz,PAH, and PM emission factors for fireplace and woodstove combustion in the San Francisco Bay region

Emissions from residential fireplace and woodstove appliances burning fuels available from the San Francisco Bay area were sampled for polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HxCBz), particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs, and the monosaccharide levoglucosan. Emission factors for these pollutants were determined, the first known characterization of this extent. Common California natural firewoods and manufactured artificial logs were tested under operating conditions intended to reflect domestic use patterns in the Bay area, which are primarily episodic burning for aesthetic reasons. Emission factors were determined by fuel type, fuel weight, mass emission rates, and energy output, highlighting differences between fuel and combustion facility type. Average PCDD/F emissions factors ranged from 0.25 to 1.4 ng toxic equivalency (TEQ)/kg of wood burned for natural wood fuels and 2.4 ng TEQ/kg for artificial logs. The natural wood emission factors are slightly lower than those which had been estimated for the U.S. inventory. Background-corrected PCBs emitted from woodstove/oak combustion (8370 ng/kg) are 3 orders of magnitude higher in mass than total PCDDs/Fs; however, their toxicity (0.014 ng TEQ/kg) is significantly lower. HxCBz emission factors varied from 13 to 990 ng/kg and were likely fuel- and appliance-specific. Relative PAH concentrations of particle-phase compounds and emission factors were consistent with others' findings. A total of 32 PAH compounds, ranging in concentration from 0.06 to 7 mg/kg, amounted to between 0.12 and 0.38% of the PM mass, depending on the wood and facility type. Preliminary analyses suggest relationships between wood combustion markers and PCDD/F levels.     

Size and Shape Effects for Gamma Prime in Alloy 738

Cast IN-738 and wrought Inconel 738 are generic applications for most metallurgical designers of gas turbine blades in the Power Generation Industry on a worldwide basis... Particularly, where first stage buckets are concerned. This is the case because both alloy types exhibit outstanding creep and stress rupture properties to provide an extended service period in a harsh environment. Typically, Alloy 738 is fired in the turbine at 1970 °F (1074 °C) which is about 0.9T _m where T _m represents the melting temperature... A very demanding service temperature, indeed. Furthermore, Alloy 738 is expected to endure this high temperature for a duration of 26,000 h at base load before being retired (R) or replaced (R′) or reused (R′′) issues are ever considered. When these three (3) problems (R-R′-R′′) are brought before a given Materials Review Board for appropriate debate, many pro and con arguments are always evident because (1) Gas turbine blades are not inexpensive and (2) The threat of field failures with possible product liability litigation is of maximum interest to all gas turbine repair shop personnel. The intent of this paper is show how gamma prime precipitate particles can be better examined and more efficiently evaluated using a new characterization method. This research is offered as a contribution to the sum of total knowledge.     

An alpha-mercaptoacrylic acid derivative is a selective nonpeptide cell-permeable calpain inhibitor and is neuroprotective

Overactivation of calcium-activated neutral protease (calpain) has been implicated in the pathophysiology of several degenerative conditions, including stroke, myocardial ischemia, neuromuscular degeneration, and cataract formation. Alpha-mercaptoacrylate derivatives (exemplified by PD150606), with potent and selective inhibitory actions against calpain, have been identified. PD150606 exhibits the following characteristics: (i) Ki values for mu- and m-calpains of 0.21 microM and 0.37 microM, respectively, (ii) high specificity for calpains relative to other proteases, (iii) uncompetitive inhibition with respect to substrate, and (iv) it does not shield calpain against inactivation by the active-site inhibitor trans-(epoxysuccinyl)-L-leucyl-amido-3-methylbutane, suggesting a nonactive site action for PD150606. The recombinant calcium-binding domain from each of the large or small subunits of mu-calpain was found to interact with PD150606. In low micromolar range, PD15O6O6 inhibited calpain activity in two intact cell systems. The neuroprotective effects of this class of compound were also demonstrated by the ability of PD150606 to attenuate hypoxic/hypoglycemic injury to cerebrocortical neurons in culture and excitotoxic injury to Purkinje cells in cerebellar slices.