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By D. M. Lewis, J. K. H. Ma, Y. Rojanasakul, J. Y. C. Ma, J. H. Kang, V. Castronova

"Tetrandrine is a bisbenzylisoquinoline alkaloid which has been shown to exhibit antifibrotic activity against silicosis. Tetrandrine is characterized by its strong binding to alveolar macrophages and inhibition of particle-induced respiratory burst activity in these phagocytes. In contrast, tubocurine and tubocurarine are structurally similar to tetrandrine but exhibit little effect on fibrosis or activation of alveolar macrophages. The objective of the present study was to test the effect of tetrandrine on macrophage production of monokines in response to occupational dusts, and to determine tetrandrine's effect on monokine-medicated cell growth using a mouse thymocyte proliferation assay and lipopolysaccharide (LPS) as a positive control. Stimulation of alveolar macrophages by respirable silica dust resulted in a release of monokines which caused a fourfold increase in thymocyte proliferation. Coal dust, on the other hand, had no effect on macrophage production of this cytokine. Tetrandrine was found to exhibit a dose-dependent inhibition of monokine release from both silica and LPS-stimulated alveolar macrophages. In experiments where thymocytes were directly treated with tetrandrine, a dose-dependent inhibition of thymocyte proliferation was noted with both interleukin-1- (IL-1) specific and nonspecific mitogenic (concanavalin A) actions. In contrast to the inhibitory potency of tetrandrine, tubocurarine was found to have no effect on either the production of monokines by LPS-stimulated alveolar macrophages or IL-I-mediated thymocyte proliferation. These results provide a correlation between the ant:fibrotic effect of tetrandrine and inhibition of macrophage activation. INTRODUCTIONThe pathogenesis of chronic pulmonary fibrosis caused by inhalation of occupational dusts has been associated with abnormal activation of alveolar macrophages such as the release of various cytokines capable of inducing fibroblast proliferation and collagen synthesis. These macrophage-derived cytokines include interleukin-1 (IL-1), tumor necrosis factor (TNF), platelet-derived growth factor (PDGF), transforming growth factor-B (TGF-(B), macrophage derived growth factor (MDGF), and interferon [1, 2].Interleukin-1 is a major macrophage-derived cytokine that has been shown to exhibit multiple biological effects on a variety of target cells. It is known to cause leukocyte [3, 4] and endothelial cell activation [5, 6], and to affect the synthesis and maintenance of the extracellular matrix by stimulation of fibroblast proliferation [7-9], synthesis of collagens [10] and gluco-saminoglycans [11], and prostaglandin E2 production [12]. In addition, IL-1 plays an important role in the initiation of an immune response through its direct activation of lymphocytes and stimulation of the production of other cytokines, such as interferons and hemopoietic colony-stimulating factors, needed for the expression of an immune response [13]. As a major cytokine in the immune-inflammatory sequela, IL-1 is also produced by epidermal, epithelial, lymphoid, and vascular tissues after infection, injury, or antigenic challenge [14]. Agents such as lipopolysaccharide (LPS), phorbol myristate acetate (PMA), immune complexes, and particulates are known to activate the synthesis and release of IL-1 by monocytes and macrophages [15]. These substances also trigger intracellular signals leading to altered arachidonic acid metabolism. Although the mechanism is still not clear, prostaglandins have been shown to suppress IL-1 translation via the induction of cyclic adenosine-monophosphate (CAMP), whereas leukotrienes produce a positive signal for IL-1 production [13]."

Mar 1, 1992

By R. V. Ramani, W. Miola, R. Srikanth, S. C. Soboleski

"Dust control in high-production longwalls requires attention to operating practices and ventilation schemes. Several studies have shown that the shearer is the major source of dust on a longwall face. Support movement has not been regarded as a major source of dust in US longwalls. Yet, under certain conditions, 31% of the shearer operator's dust exposure can be due to support movement.Several methods have been developed for the control of shield-generated dust. But the need for better methods is apparent. In this paper, the amount of airborne, respirable dust generated per shield move is estimated from specially designed experiments on longwall faces. Ten experiments were conducted on five longwall faces in four mines. Each experiment involved one face visit and lasted three to six hours. The contribution of shield movement to the airborne, respirable dust concentration immediately downwind of the shield move varied between 0.12 and 1.75 mg/m3 in the five longwall faces. The mass of airborne, respirable dust gener-ated by shield movement was found to vary between 39 and 386 mg per shield move. The results from this study reveal that control of dust from longwall shields requires a combi-nation of approaches involving alternative operating prac-tices, reducing shield dust generation rate, increasing face air flow and decreasing personnel exposure.IntroductionIn 1992, longwall mining accounted for about 36% of US underground coal production, a 240% increase from a decade ago. The absolute longwall tonnages were 46 and 133 Mt (51 and 146 million st), respectively. Compared with room-and¬pillar mining systems, the longwall mining system is charac¬terized by higher recovery, enhanced safety and higher pro¬ductivity.However, personnel dust exposure on a longwall face is higher than in other types of mining. According to Mine Safety and Health Administration (MSHA) data, fewer longwalls were in continuous compliance with the applicable dust standard in 1992 than in 1989.Controlling shearer-generated dust and reduction of per-sonnel exposure to airborne dust have commanded attention in the design of longwall faces, operational practices and ventilation schemes. Studies in the United States and abroad have revealed that support-generated dust can be a major obstacle to compliance under certain conditions (Becker et al., 1989; Bradley et al., 1983; Jankowski and Organiscak, 1983; Jankowski et al., 1990; Organiscak et al., 1985)."

Dec 1, 1996

By E. J. Kloos

This publication lists devices approved jointly by the Secretary of Interior and the Secretary of Health, Education, and Welfare, as of May 24, 1972, under provisions of Section 11.2, Part 11, Subchapter B of Chapter 1, Title 30, Code of Federal Regulations (37 F.R. 6244, March 25, 1972), for use in mines as respiratory protection in oxygen-deficient atmospheres, and in gases, vapors, dusts, fumes, and mists. Included are self-contained breathing apparatus, gas masks, and supplied-air, dust, fume, mist, and chemical-cartridge respirators. Names and addresses of manufacturers appear in the appendix.

Jan 1, 1972

By George R. McCormick

Because several new and unusual synthetic minerals were found in the system MgO-MgF₂ - SiO2 with Li * , or Nat a similar system with Geo₂ replacing Sio , plus Lit was investigated . In addition to the expected compounds of germanium , Ge - fluor - hectorite and a Ge - fluor- chrysotile were synthesized . Protoamphibole was not observed . Data are given for 69 compositions prepared in the system MgO- MgF₂ - Ge02 at 6.94 percent LiF .

Jan 1, 1964

By Russell R. Trengove

The Strawberry tungsten mine is in the Jackass Mining District, in an isolated portion of eastern Madera County, near the southeast corner of the Yosemite National Park. The deposit was discovered in 1941, and production started in 1943 when the mill was completed. With the exception of 1946 and 1947, production has been continuous. The area in the vicinity of the mine is granite containing islands of sedimentary beds highly altered by metamorphism that resulted from the intrusion of acid igneous rock. Schoelite occurs in almost vertical lenses of tactite between the limestone and the granite.

Jan 1, 1949

By G. R. Strimbeck

The Federal Bureau of Mines has been developing processes for producing synthesis gas directly from coal, oxygen, and superheated steam. An atmospheric-pressure pilot plant was constructed and operated to: 1. Determine the operability of the plant for gasifying coals of different ranks under various operating conditions. Listed in decreasing order of rank, these coals included a Pennsylvania anthracite, a bituminous A coal from the Sewickley bed, West Virginia, and a subbituminous C coal mined in the Lake de Smet region of Wyoming. 2. Determine the effect of varying operating conditions on: (a) Standard cubic feet (std.c.f.) of oxygen and pounds of coal of different rank required to make M std.c.f. of product gas (carbon monoxide plus hydrogen); (b) carbon gasified, percent; (c) exit-gas temperature, degrees F.; and (d) heat loss, B.t.u. per pound coal. 3. Compare the gasification characteristics, indicated in item 2, of coals of different rank: Bituminous A, anthracite, and subbiturninous C. 4. Determine the concentration of dust in the gases produced and the efficiency of dust removal, and investigate the relation between the sulfur content in the coals gasified and the gases produced.

Jan 1, 1960

By C. M. McCulloch

The methane content of virgin bituminous coalbed can now be measured accurately in the field with exploration core samples from vertical boreholes. The gas content of the coal per unit weight can be used either to design a mine ventilation system or to determine if degasification of the coalbed will be necessary before mining, and to determine the gas resources in the coalbed. The equipment necessary to conduct the test costs less than $50. The gas con-tent of the coal in place in the ground is determined by summing the gas lost from coring, gas measured during desorption, and the residual gas in the coal. Upon removal from the borehole, the core sample is placed in an airtight container and des orbed for several weeks until the desorption rate is below 0.05 cm3/g for 5 consecutive days. The gas lost from the core while it was being cored and the residual gas are estimated by a new graphical method. The amount of gas remaining depends upon whether the coal is friable or blocky. Friability appears to relate to the depth of the sample below the surface, fixed carbon percentage, Hardgrove grindability index, and proximity to tectonic disturbance. Friable coals emit nearly 96 pct of the total gas during desorption whereas a blocky coal emits only 60 pct of its total gas. Coalbeds that are ill defined as to their blocky or friable nature must be tested in the laboratory for unambiguous analysis.

Jan 1, 1975

By J. B. Gayle

Both immediate and long-range economic factors are associated with blending anthrafines to produce metallurgical cokes, and they warrant careful consideration of the technology of carbonization of blends containing significant proportions of inert substances in general and anthrafines in particular. This situation has resulted in numerous publications dealing with various phases of the overall problem, particular emphasis being placed on the effects of inert substances on the yields and quality of cokes produced. Because relatively little attention has been given to the expansion behavior of coal blends containing inert substances, an investigation of this problem was undertaken using the Bureau of Mines sole-heated oven. Since experiments in the sole-heated oven do not measure wall pressures directly, a new method of interpretation of sole-heated oven data, which permits estimates of wall pressures, has been proposed.

Jan 1, 1955

By M. J. Ankeny

This is a study of 58 fatal haulage accidents investigated by Federal coal-mine inspectors during the period January - June 1951. The information presented in this circular was obtained by analyzing fatal haulage accidents in 33 bituminous-coal producing counties representing 11 States. The physical conditions represent a cross section off producing coal beds. Mining and transportation methods vary, from those of small hand-loading mines to those of large modern mechanized operations. These data are thought to be representative of haulage conditions within the bituminous-coal mining industry and are submitted to follow up the Information Circular 7604 ?Analysis of Haulage Fatalities in Bituminous-Coal Mines - 1950.? Coal-mine haulage ranks second as a cause of coal-mine fatalities, and the problem of haulage safety is complex. It is subject to constant change and is comprised of numerous influencing variables, which are not always obvious. The solution to this problem will not come through the application of any standard formula or mechanical approach since the inherent factors are strongly influenced by the human equation, and the chain of circumstances is further affected by expediency.

Jan 1, 1951

By G. L. Neumann

The Andover-Sulphur Hill iron mines in Sussex County, N. J., have a production record extending over 100 years. The last production recorded was about 1880. These mines produced high-grade ore of two types: Bed ore (hematite) and blue ore (magnetite. Some sulfides (lead, zinc, and copper) were found underlying the iron deposits. Data as to size and grade of these sulfide bodies are very sketchy, Toward. J. Hewitt of Elizabeth, N. J., lessee of the Sulphur Hill mines from 194045, prospected for lead, zinc, and copper. .His Only production was several hundred tons of low-grade iron ore, which was crushed and used as heavy aggregate to make concrete blocks for ship ballast. In October and November 1942 made a magnetic survey of this area and bored six-diamond-drill holes with the dual objective of prospecting for sulfides and testing for extensions of the iron-ore deposits indicated by the magnetic survey. In 1944, an iron-mining company examined this property and diamond-drilled seven holes Between December 1949 and March 1950, the Bureau Of Mines in search of sulfide deposits, bored three additional diamond-drill holes. Two of these were on the Sulphur Hill tract and one on the adjoining Tar Hill tract.

Jan 1, 1952

By Ralph H. Espach

The value of careful fractionation in the manufacture of petroleum products is recognized more and more by petroleum refiners. Recent studies have shown that the quality of the products depends largely on the type of fractionating equipment and on the care used in operating the equipment. For example Rue3 has shown that careful fractionation of pressure distillate will greatly reduce the amount of chemical treatment necessary to produce finished gasoline. The advantages of the combination of pipe still and bubble tower in obtaining good fractionation are well recognized in the petroleum industry. However, the equipment designed in the past has in general been much too large for convenient laboratory use. The present paper describes a continuous-distillation apparatus for the laboratory study of fractionation. This apparatus has given very satisfactory results in the study of different crude oils and petroleum products. A discussion of the theory and action of bubble towers has not been given, as this subject has been discussed previously by Cooke and Rue4. It is believed that the distillation curves of the products obtained from this apparatus show clearly its capabilities.

Jan 1, 1928

By Nar S. Dala1, Xianglin Shi, Val Vallyathan

"Electron spin resonance (ESRJ and cytotoxicity measurements were made on newly fractured silica to examine specifically the role of the fracture-induced, silicon-based radicals (Si· and SiO·) and silica-generated hydroxyl (·OH) radicals in the mechanism of the cell membrane damage by silica. The concentration of the Si· and SiO · radicals was controlled through decay processes, thermal annealing, and boiling, while that of the ·OH radicals was varied by using catalase, superoxide dismutase, KMnO, Na;iSeO:y ascorbic acid, and metal ions, and monitored via ESR spectroscopy. The dust's cytotoxicity potential was evaluated by measuring the silica-induced hemolysis and also by determining lipid peroxidation (using linoleic acid). From the comparison of hemolysis and ESR results it is deduced that the radicals play little or no role in the silica-induced hemolysis. However, the lipid peroxidation data indicate that the radicals might be involved in the initiation of an oxidative chain reaction leading to the macrophage membrane damage through lipid peroxidation. INTRODUCTIONThe biochemical mechanism of quartz-related pneumoconiosis is still not fully understood. It is believed, nevertheless, that one event of primary importance is the perturbation of cell membranes by the dust particles (Allison et al., 1966; Allison and Harrow, 1971; Bateman et al., 1982; Parazzi et al., 1968; Reiser and Last, 1979; Shi et al., 1989; Summerton et al., 1977). The ensuing cell: membrane damage unleashes certain lytic enzymes resulting in additional cell injury and eventual fibrosis (Nolan et al., 1981; Summerton et al., 1977). Thus considerable effort is currently being made toward the understanding of the processes by which quartz particles disrupt the membrane of a red blood cell (RBC) or a pulmonary alveolar macrophage (PAM). A simple but important method of evaluating the membrane damage potential of a dust is the hemolysis test (Harington et al., 1971). Even though this test is used routinely for screening dusts for their cytotoxicity potential, the biochemical mechanisms underlying the cell lysis by many dusts, including quartz, is still controversial (Kilroe-Smith, 1974; Singh and Rahman, 1987), and this provided us the impetus for the present undertaking."

Jan 1, 1990

By A. Adams

The quality of hafnium metal produced by the Kroll process depends upon the purity of the hafnium tetrachloride. This investigation of methods for purification of hafnium tetrachloride was undertaken to aid in producing a higher purity hafnium metal than is currently produced by the Kroll process, The quantities of metallic impurities in hafnium metal were decreased by contact with molten alkali-metal chloride salt. Contact was achieved by a semicontinuous process of bubbling gaseous hafnium tetrachloride through a molten salt bath or by a batch process, first fusing the tetrachloride with a combination of alkali chlorides and then heating the mixture to sublime the hafnium tetrachloride. Low-melting mixtures of sodium, potassium, and lithium chlorides were used to purify hafnium tetrachloride. About 30 percent of the initial hafnium tetrachloride was trapped during purification with alkali- metal chloride salts. The 95-percent confidence limits (6)4 for the amount of oxygen decrease 60 and 34.3 parts per million when the batch purification is combined with a reduction so that both take place in the same equipment,

Jan 1, 1961

By L. P. Kleinmann

To control the formation of acid drainage at its source, the Bureau of Mines has investigated the role of iron-oxidizing bacteria in the oxidation of pyrite. In laboratory tests, it was determined that Thio-bacillus ferrooxidans could be controlled in coal refuse using anionic surfactants, with an associated decrease in acid production of about 75 pet. Based on these results, large-scale tests were conducted at an 8-acre active coal refuse area in northern West Virginia and an 11-acre inactive refuse pile in southern West Virginia. Acid production was decreased 60 to 95 pet for 4 to 5 months after application of 55 gal/ acre of 30-pct sodium lauryl sulfate solution. To date, effluent surfactant concentrations have been extremely low. Either a hydroseeder or a road-watering truck can be used to apply the surfactant. Since the surfactant solution must reach the pyritic material to be effective, sites that have been reclaimed are generally not amenable to these procedures. A simple laboratory test is described that provides an estimate of adsorption potential; this can be used to calculate a safe application rate.

Jan 1, 1983

By David E. Siskind

The Bureau of Mines recorded particle accelerations in the mine roof produced by three types of explosives in the Pilot Knob Pellet Co. mine, Pilot Knob, Mo. Examined were the effectiveness of cube root, square root, and two-thirds power scaling in grouping the underground blast vibration data, and the effects of mine geometry, rock type, explosive type, and charge size on blast vibration levels. A propagation law for this mine was determined. The scaling factor of the square root of the charge weight was developed from previous Bureau studies of vibrations from quarry blasts, and in under-ground blasting both square root and cube root scaling were found applicable for scaling particle vibration data. The vibrations from the Pilot Knob blasts were best grouped by a square-root scaling factor. The empirical propagation equation AW1/2 = 76,250 (R/W1/2)-2.61 where A is the peak acceleration in g's, W is the charge weight in pounds, and R is the distance from the blast in feet, may be used to describe vibration amplitudes from charges fired with zero delay caps or with a single cap at Pilot Knob. Statistically significant differences were found in the vibration levels generated by the different explosives. The Power Primer (75-percent weight-strength ammonia gelatin dynamite) produced levels of vibration of 1.7 to 2.4 times those of AN-FO and slurry explosives; the latter two are approximately equal.

Jan 1, 1973

By R. V. Ramani, R. L. Grayson, R. L. Frantz, V. A. Marple, W. R. Myers, K. L. Rubow, Mutmansky. J. M., T. J. Stobbe

"An investigation of protocols for research performed from 1953 to 1988 on pneumoconioses (with emphasis on diseases related to coal and silica) was conducted in the Generic Mineral Technology Center for Respirable Dust. In addition, interviews were conducted with prominent U.S. medical researchers, aerosol scientists and engineers in government, industry, and universities to determine dust sources, dust preparation methods, laboratory protocols, and determinant variables related to in vitro and in vivo research and assess the comparability of results.Since the original report on the protocol project, additional research regarding free radical existence in freshly produced dust particles and the shape and contamination of particles generated for research purposes has further heightened scientists' concerns. As indicated by current research, fresher dust particles and those with more angular shapes may have a different level of reactivity in biological systems than do older or more rounded particles. Therefore, research on dust preparation methods for biomedical studies was undertaken and will be outlined here.Results of protocol review and interviews are summarized. Research on size reduction methods and their particle characteristics plus some recommendations concerning dust preparation methods and reporting in biomedical publications are also presented. Recent evidence indicates that these recommendations may be of importance in comparing and interpreting research results."

Nov 1, 1995

By R. Barany

Thermodynamic calculations pertaining to the minerals gibbsite, kaolinite, halloysite, and dickite have been hampered by the lack of adequate heat and free energy of formation data. Previous data for gibbsite were highly uncertain, and there were no data for the other three substances. By use of hydrofluoric acid solution calorimetry, the Bureau of Mines derived heat of formation values from the elements and from the oxides for the four substances, and the data were combined with known entropy values to obtain the corresponding free energies of formation. The results show that gibbsite and halloysite are thermodynamically unstable with respect to the oxides (a- alumina, a- quartz, and liquid water) at 298.15° K,, while kaolinite and dickite are only moderately stable (to about the same degree), The instability of halloysite, in comparison with kaolinite and dickite, results in a 60°-lower equilibrium decomposition temperature.

Jan 1, 1961

By I. AITKENS

The basic mining law of Cuba is contained in the basic Spanish mining decree having the effect of law December 29 , 1868. This legislation has remained substantially unchanged , with the exception of a few minor administrative changes made by the present Government . These changes provide for the register of mines , oil wells , and operations of such nature , and also provide for the keeping of records showing the value of minerals taken out . By Royal decree of April 17 , 1883 , the law of mines enacted for the Peninsula ( Spain ) on July 6 , 1859 , and the General Bases of December 29 , 1868 , were declared in force in Cuba . In order to encourage the mining of iron org , in 1883 the Crow of Spain issued a royal decree to the following effect.

Jul 1, 1931

By S. H. Ash

As part of the work done at the Washington coal mines during the year 1929 , a study was made of the safety practices in and about the mines . Inasmuch as electrical blasting has made considerable headway it is interesting to note the manner in which it is done and the reasons why it was discarded at some of the mines . Blasting is done at the mines in the State by means of capped fuse , electric blasting " caps , " and in some instances by electric delay detonators . Black blasting powder with fuse is used at most of the open- light mines . The use of squibs was discontinued several years ago because the coal operators , without exception , recognized the dangers incidental to their use . Permissible explosive and dynamite are also used at some of the open- light mines . With the exception of some rock work and the driving of level work in gangways and air courses the explosive is detonated by means of capped fuse .

Apr 1, 1930

By Charles R. Harrison

The purpose of this study and resulting development of the training program, "Safety--Let's Make It Happen" was to determine the relation of concepts to the development of desired Health and Safety behavior. After extensive pre-contract study, it was hypothesized that improved acceptance and understanding of the Federal Coal Mine Health and Safety Act of 1969 could possibly contribute to the reduction of accidents. Second, in order for an individual to accept and understand the Act, he or she must have a working knowledge of its purposes and application. Third, acceptance and understanding of the Act, necessary to protect the individual from negligence, was imperative. Fourth, an actual operating company could provide the base in which to test these hypotheses in a meaningful manner and develop this type of training program. Six assumptions were agreed upon before embarking on this study and training program development. (1) In the cognitive process, a concept introduction into an individual's personality may result in a behavior quite different than if he or she had been exposed to a different concept.

Jan 1, 1977