Effect of gas release in hot molding on flexural strength of composite friction brake

NASA Astrophysics Data System (ADS)

Rusdja, Andy Permana; Surojo, Eko; Muhayat, Nurul; Raharjo, Wijang Wisnu

2018-02-01

Composite friction brake is a vital part of braking system which serves to reduce the speed of vehicle. To fulfill the requirement of brake performance, composite friction brake must have friction and mechanical characteristic as required. The characteristics of composite friction brake are affected by brake material formulation and manufacturing parameter. In the beginning of hot molding, intermittent hot pressing was carried out to release the gases that consist of ammonia gas and water vapor. In composite friction brake, phenolic resin containing hexamethylenetetramine (HMTA) is often used as a binder. During hot molding, the reaction of phenolic resin and HMTA forms ammonia gas. Hot molding also generates water vapor because raw materials absorb moisture from environment when they are placed in storage. The gas release in hot molding is supposed affecting mechanical properties because it avoid entrapped gas in composite, so that this research investigated effect of gas release on flexural strength. Manufacturing of composite specimen was carried out as follow: mixing of raw materials, cold molding, and hot molding. In this research, duration of intermittent hot pressing and number of gas release were varied. The flexural strength of specimen was measured using three point bending test. The results showed that flexural strength specimens that were manufactured without gas release, using 4 times gas release with intermittent hot pressing for 5 and 10 seconds were not remarkably different. Conversely, hot molding using 4 times gas release with intermittent hot pressing for 15 seconds decreased flexural strength of composite. Hot molding using 2, 4, and 8 times gas release with intermittent hot pressing for 10 seconds also had no effect on increasing flexural strength. Increasing of flexural strength of composite was obtained only by using 6 times gas release with intermittent hot pressing for 10 seconds.

Airfield Damage Repair (ADR); Polymer Repair of Airfields Summary of Research

DTIC Science & Technology

2007-12-01

reported in section 4.3.1. Prior to mixing, the stainless steel bowl, paddle and molds were sprayed with an industrial silicone release agent, Zip-Slip...aggressive foaming and segregation problems. airfield damage repair, (ADR), polymer, concrete, polymer concrete, crater repair U U U UU 30 R. Craig...Polymer Technology for Agile Combat Support to develop a rapid crater repair using resin binders for indigenous materials. The research team consisted of

Transfer molding processes for nanoscale patterning of poly-L-lactic acid (PLLA) films

NASA Astrophysics Data System (ADS)

Dhakal, Rabin; Peer, Akshit; Biswas, Rana; Kim, Jaeyoun

2016-03-01

Nanoscale patterned structures composed of biomaterials exhibit great potential for the fabrication of functional biostructures. In this paper, we report cost-effective, rapid, and highly reproducible soft lithographic transfer-molding techniques for creating periodic micro- and nano-scale textures on poly (L-lactic acid) (PLLA) surface. These artificial textures can increase the overall surface area and change the release dynamics of the therapeutic agents coated on it. Specifically, we use the double replication technique in which the master pattern is first transferred to the PDMS mold and the pattern on PDMS is then transferred to the PLLA films through drop-casting as well as nano-imprinting. The ensuing comparison studies reveal that the drop-cast PLLA allows pattern transfer at higher levels of fidelity, enabling the realization of nano-hole and nano-cone arrays with pitch down to ~700 nm. The nano-patterned PLLA film was then coated with rapamycin to make it drug-eluting.

Organic materials for ceramic molding processes

NASA Technical Reports Server (NTRS)

Saito, K.

1984-01-01

Ceramic molding processes are examined. Binders, wetting agents, lubricants, plasticizers, surface active agents, dispersants, etc., for pressing, rubber pressing, sip casting, injection casting, taping, extrusion, etc., are described, together with forming machines.

Preparation and release study of Triclosan in polyethylene/Triclosan anti-bacterial blend.

PubMed

Kamalipour, Jamshid; Masoomi, Mahmood; Khonakdar, Hossein Ali; Razavi, Seyed Mohammad Reza

2016-09-01

In this study, medium density polyethylene (MDPE) incorporated with Triclosan antibacterial substance has been prepared and Triclosan release rate was investigated. The crystallinity level and matrix polarity, as two significant parameters in antibacterial release control, were studied. Triclosan, a well-established widespread antibacterial agent, was incorporated into medium density polyethylene (MDPE) and Maleic anhydride grafted polyethylene (PE-g-MA) was used to change the polarity of the MDPE matrix. A masterbatch of 10wt% Triclosan incorporated with the MDPE and various PE-g-MA concentrations were prepared using an internal mixer. Then the masterbatch was diluted in the MDPE matrix to produce compounds with 0.1, 0.5, and1wt% Triclosan via twin screw extruder. The compounds were molded by compression molding method and then were cooled in three different cooling rate methods: isothermal cooling (I), quenching (Q),and moderate 5-10°C/min cooling rate (M). Cooling rate effects on crystallinity level were investigated applying sample density measurement. UV-vis absorption spectroscopy was used to probe the release of Triclosan. Antibacterial properties of the compounds against Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus were measured. The results showed that by addition of PE-g-MA, Triclosan release rate was increased. It was confirmed that the sample crystallinity was decreased by the cooling rate enhancement. The results also showed that quenched samples indicated higher release of Triclosan. Cooling rate reduction and raising the polarity increased the release of Triclosan and improved the antibacterial properties of the compounds. Copyright © 2016 Elsevier B.V. All rights reserved.

Process for slip casting textured tubular structures

DOEpatents

Steinlage, Greg A.; Trumble, Kevin P.; Bowman, Keith J.

2002-01-01

A process for centrifugal slip casting a textured hollow tube. A slip made up of a carrier fluid and a suspended powder is introduced into a porous mold which is rotated at a speed sufficient to create a centrifugal force that forces the slip radially outward toward the inner surface of the mold. The suspended powder, which is formed of particles having large dimensional aspect ratios such as particles of superconductive BSCCO, settles in a textured fashion radially outward toward the mold surface. The carrier fluid of the slip passes by capillary action radially outward around the settled particles and into the absorbent mold. A layer of mold release material is preferably centrifugally slip cast to cover the mold inner surface prior to the introduction of the BSCCO slip, and the mold release layer facilitates removal of the BSCCO greenbody from the mold without fracturing.

Foam injection molding of thermoplastic elastomers: Blowing agents, foaming process and characterization of structural foams

NASA Astrophysics Data System (ADS)

Ries, S.; Spoerrer, A.; Altstaedt, V.

2014-05-01

Polymer foams play an important role caused by the steadily increasing demand to light weight design. In case of soft polymers, like thermoplastic elastomers (TPE), the haptic feeling of the surface is affected by the inner foam structure. Foam injection molding of TPEs leads to so called structural foam, consisting of two compact skin layers and a cellular core. The properties of soft structural foams like soft-touch, elastic and plastic behavior are affected by the resulting foam structure, e.g. thickness of the compact skins and the foam core or density. This inner structure can considerably be influenced by different processing parameters and the chosen blowing agent. This paper is focused on the selection and characterization of suitable blowing agents for foam injection molding of a TPE-blend. The aim was a high density reduction and a decent inner structure. Therefore DSC and TGA measurements were performed on different blowing agents to find out which one is appropriate for the used TPE. Moreover a new analyzing method for the description of processing characteristics by temperature dependent expansion measurements was developed. After choosing suitable blowing agents structural foams were molded with different types of blowing agents and combinations and with the breathing mold technology in order to get lower densities. The foam structure was analyzed to show the influence of the different blowing agents and combinations. Finally compression tests were performed to estimate the influence of the used blowing agent and the density reduction on the compression modulus.

Production of Insulated Footwear Using Liquid Injection Molding Equipment. 2. Instruction Manual

DTIC Science & Technology

1980-09-01

Viscosity 0 70 0 C 20 Poise Speci fic Gravity 1.04 Nonstickenstoffe release agent and Stapler Wax are commercial preparations with no typical...soluble in most organic solvents. It decomposes in acidic solvents. 2. HANDLING LUCEL-4 is intended for industrial use only. It should be handled with...SENSITIVE GLUED 3" wide (7.6 cm), 60 lb, TAPE (27 kilograms), 3" pr. SOURCE: Industrial Paper Co., Waterbury, CT 47 11. CASE Plain Kraft, Printed

Parylene C coating for high-performance replica molding.

PubMed

Heyries, Kevin A; Hansen, Carl L

2011-12-07

This paper presents an improvement to the soft lithography fabrication process that uses chemical vapor deposition of poly(chloro-p-xylylene) (parylene C) to protect microfabricated masters and to improve the release of polymer devices following replica molding. Chemical vapor deposition creates nanometre thick conformal coatings of parylene C on silicon wafers having arrays of 30 μm high SU8 pillars with densities ranging from 278 to 10,040 features per mm(2) and aspect ratios (height : width) from 1 : 1 to 6 : 1. A single coating of parylene C was sufficient to permanently promote poly(dimethyl)siloxane (PDMS) mold release and to protect masters for an indefinite number of molding cycles. We also show that the improved release properties of parylene treated masters allow for fabrication with hard polymers, such as poly(urethane), that would otherwise not be compatible with SU8 on silicon masters. Parylene C provides a robust and high performance mold release coating for soft lithography microfabrication that extends the life of microfabricated masters and improves the achievable density and aspect ratio of replicated features.

Foam injection molding of poly(lactic acid) with physical blowing agents

NASA Astrophysics Data System (ADS)

Pantani, R.; Sorrentino, A.; Volpe, V.; Titomanlio, G.

2014-05-01

Foam injection molding uses environmental friendly blowing agents under high pressure and temperature to produce parts having a cellular core and a compact solid skin (the so-called "structural foam"). The addition of a supercritical gas reduces the part weight and at the same time improves some physical properties of the material through the promotion of a faster crystallization; it also leads to the reduction of both the viscosity and the glass transition temperature of the polymer melt, which therefore can be injection molded adopting lower temperatures and pressures. These aspects are of extreme interest for biodegradable polymers, which often present a very narrow processing window, with the suitable processing temperatures close to the degradation conditions. In this work, foam injection molding was carried out by an instrumented molding machine, able to measure the pressure evolution in different positions along the flow-path. The material adopted was a biodegradable polymer, namely the Poly(lactic acid), PLA. The effect of a physical blowing agent (PBA) on the viscosity was measured. The density reduction and the morphology of parts obtained by different molding conditions was assessed.

CROSS REACTIVITY IN ALLERGIC ASTHMA-LIKE RESPONSES BETWEEN MOLD AND HOUSE DUST MITE IN MICE

EPA Science Inventory

Molds are ubiquitous in the environment and exposures to molds contribute to various human diseases including allergic asthma. Some mold allergens have been implicated as the causal agent for allergic asthma. Western blot analysis demonstrated IgE-binding cross-reactivity among m...

Effect of fluorescent pseudomonades and Trichoderma sp. and their combination with two chemicals on Penicillium digitatum caused agent of citrus green mold.

PubMed

Zamani, M; Tehrani, A Sharifi; Ahmadzadeh, M; Abadi, A Alizadeh Ali

2006-01-01

Citrus green mold (Penicillium digitatum) causes economic losses. Chemical fungicides such as imazalil provide the primary means for controlling green mold decay of citrus fruits. Continuous use of fungicides has faced two major obstacles- increasing public concern regarding contamination of perishables with fungicidal residues, and proliferation of resistance in the pathogen populations. The aim of this research was to determine if the attacks of green mold on orange could be reduced by usage of biocontrol agent alone or in combination with low dosage of imazalil or sodium bicarbonate. Pseudomonas fluorescens isolate PN, P. fluorescens isolate PS and Trichoderma virens isolate TE were evaluated as potential biological agents for control of green mold of oranges caused by P. digitatum. Increasing concentration of SB decreased spore germination of P. digitatum. In laboratory tests, a cell suspension (10(8) cells per ml.) of bacterial strains reduced the incidence of green mold. On fruits surface biocontrol activity of antagonistic isolates was significantly increased when combined with low dosage of imazalil (500ppm) or sodium carbonate (5%). Effect of Trichoderma virens on controlling P. digitatum was better than others with or without these chemicals.

EMISSION EXPOSURE MODEL FOR TRANSPORT OF TOXIC MOLD

EPA Science Inventory

The paper presents the results of a study of the release of Stachybotrys chartarum spores from contaminated gypsum wallboard and of tests on the effects of environmental conditions on the release of viable and non-viable spores and fragments. Biocontaminants such as mold spores a...

Mold Charlatans.

ERIC Educational Resources Information Center

Woody, Daniel

2002-01-01

Offers a primer on toxic mold and its removal, warning against ignorant or unethical mold remediation companies and offering five considerations (checking references, considering the big picture, sampling more than the air, considering release, and considering the source) when hiring such services. (EV)

Aerosolization of Particulate (1→3)-β-d-Glucan from Moldy Materials▿

PubMed Central

Seo, Sung-Chul; Reponen, Tiina; Levin, Linda; Borchelt, Tiffany; Grinshpun, Sergey A.

2008-01-01

Mold-damaged building materials may contain biologically active agents, such as (1→3)-β-d-glucan, allergens, and mycotoxins, which have been associated with adverse health effects. The release of these components from contaminated surfaces into the air is not well understood. The purpose of this study was to characterize the release of particulate (1→3)-β-d-glucan from the surface of artificially mold-contaminated materials. Aspergillus versicolor and Stachybotrys chartarum were grown on malt extract agar (MEA), white ceiling tiles, and a wall-papered gypsum board for 1 and 6 months. The (1→3)-β-d-glucan on the surfaces of moldy materials and in air samples collected from these materials was analyzed by the Limulus amebocyte lysate assay. The aerosolization ratio was defined as the amount of (1→3)-β-d-glucan in the air divided by the amount on the surface. The results showed that the aerosolization of particulate (1→3)-β-d-glucan was influenced mainly by the type of material and the fungal species. For A. versicolor, the aerosolization ratios of particulate (1→3)-β-d-glucan released from the three types of material were not significantly different. However, the ratios for S. chartarum released from ceiling tiles and gypsum board were significantly higher than the ratios for this organism released from MEA (P < 0.001) and were comparable to those for A. versicolor. These findings indicate that the use of MEA in aerosolization experiments is likely to underestimate the release of S. chartarum particles from building materials. These results provide important background information for design of future laboratory or animal experiments, as well as for interpretation of field measurement data. PMID:18065630

Respiratory and Allergic Health Effects of Dampness, Mold, and Dampness-Related Agents: A Review of the Epidemiologic Evidence

PubMed Central

Mendell, Mark J.; Mirer, Anna G.; Cheung, Kerry; Tong, My; Douwes, Jeroen

2011-01-01

Objectives Many studies have shown consistent associations between evident indoor dampness or mold and respiratory or allergic health effects, but causal links remain unclear. Findings on measured microbiologic factors have received little review. We conducted an updated, comprehensive review on these topics. Data sources We reviewed eligible peer-reviewed epidemiologic studies or quantitative meta-analyses, up to late 2009, on dampness, mold, or other microbiologic agents and respiratory or allergic effects. Data extraction We evaluated evidence for causation or association between qualitative/subjective assessments of dampness or mold (considered together) and specific health outcomes. We separately considered evidence for associations between specific quantitative measurements of microbiologic factors and each health outcome. Data synthesis Evidence from epidemiologic studies and meta-analyses showed indoor dampness or mold to be associated consistently with increased asthma development and exacerbation, current and ever diagnosis of asthma, dyspnea, wheeze, cough, respiratory infections, bronchitis, allergic rhinitis, eczema, and upper respiratory tract symptoms. Associations were found in allergic and nonallergic individuals. Evidence strongly suggested causation of asthma exacerbation in children. Suggestive evidence was available for only a few specific measured microbiologic factors and was in part equivocal, suggesting both adverse and protective associations with health. Conclusions Evident dampness or mold had consistent positive associations with multiple allergic and respiratory effects. Measured microbiologic agents in dust had limited suggestive associations, including both positive and negative associations for some agents. Thus, prevention and remediation of indoor dampness and mold are likely to reduce health risks, but current evidence does not support measuring specific indoor microbiologic factors to guide health-protective actions. PMID:21269928

Use of 2,5-dimethyl-2,5-hexane diamine as a curing agent for epoxy resins. [Patent application

DOEpatents

Rinde, J.A.; Newey, H.A.

Primary diamines are prepared for use as a curing agent for epoxy resins. These curing agents can be used to form epoxy resin mixtures useful in filament winding and preimpregnated fiber molding and in formulating film adhesives, powder coatings and molding powders. The epoxy mixtures form for such uses a room temperature non-reacting, intermediate stable state which has a latent cross-linking capability.

Hollow spherical shell manufacture

DOEpatents

O'Holleran, T.P.

1991-11-26

A process is disclosed for making a hollow spherical shell of silicate glass composition in which an aqueous suspension of silicate glass particles and an immiscible liquid blowing agent is placed within the hollow spherical cavity of a porous mold. The mold is spun to reduce effective gravity to zero and to center the blowing agent, while being heated so as to vaporize the immiscible liquid and urge the water carrier of the aqueous suspension to migrate into the body of the mold, leaving a green shell compact deposited around the mold cavity. The green shell compact is then removed from the cavity, and is sintered for a time and a temperature sufficient to form a silicate glass shell of substantially homogeneous composition and uniform geometry. 3 figures.

Hollow spherical shell manufacture

DOEpatents

O'Holleran, Thomas P.

1991-01-01

A process for making a hollow spherical shell of silicate glass composition in which an aqueous suspension of silicate glass particles and an immiscible liquid blowing agent is placed within the hollow spherical cavity of a porous mold. The mold is spun to reduce effective gravity to zero and to center the blowing agent, while being heated so as to vaporize the immiscible liquid and urge the water carrier of the aqueous suspension to migrate into the body of the mold, leaving a green shell compact deposited around the mold cavity. The green shell compact is then removed from the cavity, and is sintered for a time and a temperature sufficient to form a silicate glass shell of substantially homogeneous composition and uniform geometry.

Decontamination formulation with additive for enhanced mold remediation

DOEpatents

Tucker, Mark D [Albuquerque, NM; Irvine, Kevin [Huntsville, AL; Berger, Paul [Rome, NY; Comstock, Robert [Bel Air, MD

2010-02-16

Decontamination formulations with an additive for enhancing mold remediation. The formulations include a solubilizing agent (e.g., a cationic surfactant), a reactive compound (e.g., hydrogen peroxide), a carbonate or bicarbonate salt, a water-soluble bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate), a mold remediation enhancer containing Fe or Mn, and water. The concentration of Fe.sup.2+ or Mn.sup.2+ ions in the aqueous mixture is in the range of about 0.0001% to about 0.001%. The enhanced formulations can be delivered, for example, as a foam, spray, liquid, fog, mist, or aerosol for neutralization of chemical compounds, and for killing certain biological compounds or agents and mold spores, on contaminated surfaces and materials.

Susceptibility testing of terbinafine alone and in combination with amphotericin B, itraconazole, or voriconazole against conidia and hyphae of dematiaceous molds.

PubMed

Biancalana, Fernanda Simas Corrêa; Lyra, Luzia; Moretti, Maria Luiza; Schreiber, Angélica Zaninelli

2011-12-01

Studies have demonstrated excellent in vivo efficacy of terbinafine combined with other antifungal agents against dematiaceous molds; however, there is a lack of in vitro studies. Most studies evaluated conidia inocula, but susceptibility testing of hyphae could mimic the fungal status in infected tissues and might reflect the therapeutic potential of the agent. We investigated the in vitro susceptibility of terbinafine alone and in combination with amphotericin B, itraconazole, or voriconazole against conidia by microdilution and dynamic measurement of hyphae growth of dematiaceous molds. The MIC values for hyphae were, until 3 dilutions, below the MIC obtained for conidia. The results indicated 100% synergistic interactions between terbinafine and azoles or amphotericin B in all tests, but lower MICs for hyphae. In conclusion, our findings allow us to say that the hyphal form of tested dematiaceous molds showed high susceptibility to all antifungal agents evaluated, alone and in combination with terbinafine. Copyright © 2011 Elsevier Inc. All rights reserved.

Evaluation of antifungal activity of carbonate and bicarbonate salts alone or in combination with biocontrol agents in control of citrus green mold.

PubMed

Zamani, M; Sharifi Tehrani, A; Ali Abadi, A Alizadeh

2007-01-01

The aim of this research was to determine if the attacks of green mold on orange could be reduced by edible salts alone or in combination with biocontrol agent. For this purpose toxicity to Pantoea digitatum and practical use of sodium carbonate (SC), sodium bicarbonate (SBC) and potassium carbonate, and potassium bicarbonate alone or in combination with antagonistic bacteria (Pseudomonas fluorescens isolate PN, Bacillus subtilis isolate VHN, Pantoea agglomerans isolate CA) to control green mold were determined. All were fungistatic. SC and SBC were equal and superior to the other salts for control of green mold on oranges inoculated 6h before treatment and were chosen for subsequent trails under cold storage conditions. The biocontrol agents were found completely tolerant to 3% sodium bicarbonate and sodium carbonate at room temperature; although their culturability was reduced by > 1000-fold after 60 min in 1% other salt solutions. Satisfactory results were also obtained with the combined treatment for control of green mold. A significant increase in biocontrol activity of all isolate was observed when combined with sodium carbonate and sodium bicarbonate. The treatments comprising CA combined with SB was as effective as fungicide treatment. Thus, use of sodium bicarbonate treatment at 3% followed by the antagonist P. agglomerans CA could be an alternative to chemical fungicides for control of green mold on oranges.

21 CFR 178.3130 - Antistatic and/or anti-fogging agents in food-packaging materials.

Code of Federal Regulations, 2010 CFR

2010-04-01

... antistatic agent at levels not to exceed 0.2 percent by weight in molded or extruded high-density polyethylene (having a density ≥0.95 g/cm3 and polypropylene containers that contact food only of the types... levels not to exceed 0.15 pct by weight in molded or extruded polyethylene containers that contact food...

Azole-based antimycotic agents inhibit mold on unseasoned pine

Treesearch

Carol. A. Clausen; Vina W. Yang

2005-01-01

Inhibiting the growth of mold fungi on cellulose-based building materials may be achievable through the use of azole-based antimycotics. Azoles were variably effective against mold fungi that are frequently found on wood and wood products. Unseasoned southern yellow pine specimens that were dip-treated with varying concentrations of eight azoles were evaluated for...

Transparent ceramics and methods of preparation thereof

DOEpatents

Hollingsworth, Joel P [Oakland, CA; Kuntz, Joshua D [Livermore, CA; Seeley, Zachary M [Pullman, WA; Soules, Thomas F [Livermore, CA

2011-10-18

According to one embodiment, a method for forming a transparent ceramic preform includes forming a suspension of oxide particles in a solvent, adding the suspension to a mold of a desired shape, and uniformly curing the suspension in the mold for forming a preform. The suspension includes a dispersant but does not include a gelling agent. In another embodiment, a method includes creating a mixture without a gelling agent, the mixture including: inorganic particles, a solvent, and a dispersant. The inorganic particles have a mean diameter of less than about 2000 nm. The method also includes agitating the mixture, adding the mixture to a mold, and curing the mixture in the mold at a temperature of less than about 80.degree. C. for forming a preform. Other methods for forming a transparent ceramic preform are also described according to several embodiments.

Formulation and evaluation of controlled release antibiotic biodegradable implants for post operative site delivery.

PubMed

Mathur, Vijay; Mudnaik, Rajesh; Barde, Laxmikant; Roy, Arghya; Shivhare, Umesh; Bhusari, Kishore

2010-03-01

Biodegradable implants of ciprofloxacin hydrochloride for post operative site delivery were prepared using glyceryl monostearate and different concentrations of polyethylene glycol (PEG 6000), glycerol and Tween 80 as erosion enhancers by compression and molding technique. Formulations were subjected to in vitro drug release by the USP dissolution method, while promising formulations were subjected to in vitro drug release by the agar gel method and also to stability studies. It was observed that glyceryl monostearate formed hydrophobic matrix and delayed the drug delivery. Antibiotic release profile was controlled by using different combinations of erosion enhancers. The formulation prepared by the compression method showed more delayed release compared to formulations prepared by the molding method.

Evaluation of alternative cleaners for solder flux and mold release removal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lopez, E.P.; Peebles, D.E.; Reich, J.E.

1991-01-01

As part of a solvent substitution program, an evaluation of selected alternative cleaners for solder flux and mold release removal has been performed. Six cleaners were evaluated for their efficiency in removing a rosin mildly activated flux and a silicone mold release from copper, 17-4PH stainless steel, polyimide quartz glass and tin-lead surfaces. A parallel effort also studied deionized water removal of organic acid fluxes. Auger electron spectroscopy and X-ray photoelectron spectroscopy were used to determine relative elemental cleanliness of the outermost atomic layers. An Omega Meter Test was used to measure residual ionic contamination. Water drop contact angles weremore » used to measure the effectiveness of silicone removal from Cu substrates. In most cases, the cleanliness levels were good to excellent. 10 refs., 8 figs., 19 tabs.« less

Single and Dual Drug Release Patterns from Shellac Wax-Lutrol Matrix Tablets Fabricated with Fusion and Molding Techniques

PubMed Central

Phaechamud, T.; Choncheewa, C.

2015-01-01

The objective of this investigation was to prepare the shellac wax matrix tablets by fusion and molding technique incorporated with Lutrol in different ratios to modify the hydrophobicity of matrix tablet. The matrix tablets with single drug were loaded either with propranolol hydrochloride or hydrochlorothiazide as hydrophilic and hydrophobic model drugs, and a dual drug formula was also prepared. The single and dual drug release patterns were studied in a dissolution apparatus using distilled water as medium. Propranolol hydrochloride released from matrix was easier than hydrochlorothiazide. Drug release from shellac wax matrix could be enhanced by incorporation of Lutrol. However retardation of drug release from some matrix tablets was evident for the systems that could form dispersion in the dissolution medium. The gel network from high content of Lutrol was hexagonal which was a dense and more compact structure than the other structures found when low amounts of Lutrol were present in the formula. Therefore, the formulae with high content of Lutrol could prolong drug release more efficiently than those containing low content of Lutrol. Hence shellac wax matrix could modulate the drug release with the addition of Lutrol. Sustainable dual drug release was also obtained from these developed matrix tablets. Thus shellac wax-Lutrol component could be used as a potential matrix tablet prepared with fusion and molding technique with excellent controlled drug release. PMID:25767320

Use of 2,5-dimethyl-2,5-hexane diamine as a curing agent for epoxy resins

DOEpatents

Rinde, J.A.; Newey, H.A.

1981-02-24

Primary diamines are disclosed of the formula shown in a diagram wherein R is a straight chain saturated hydrocarbon of 2 to 4 carbons, a disubstituted benzene ring, or disubstituted dibenzomethane for use as a curing agent for epoxy resins. These curing agents can be used to form epoxy resin mixtures useful in filament winding and pre-impregnated fiber molding and in formulating film adhesives, powder coatings and molding powders. The epoxy mixtures form for such uses as room temperature non-reacting, intermediate stable state which has a latent cross-linking capability.

Use of 2,5-dimethyl-2,5-hexane diamine as a curing agent for epoxy resins

DOEpatents

Rinde, James A. [Livermore, CA; Newey, Herbert A. [Lafayette, CA

1981-02-24

Primary diamines of the formula ##STR1## wherein R is a straight chain saturated hydrocarbon of 2 to 4 carbons, a disubstituted benzene ring, or disubstituted dibenzo methane for use as a curing agent for epoxy resins. These curing agents can be used to form epoxy resin mixtures useful in filament winding and pre-impregnated fiber molding and in formulating film adhesives, powder coatings and molding powders. The epoxy mixtures form for such uses as room temperature non-reacting, intermediate stable state which has a latent cross-linking capability.

Complexing Agents and pH Influence on Chemical Durability of Type I Molded Glass Containers.

PubMed

Biavati, Alberto; Poncini, Michele; Ferrarini, Arianna; Favaro, Nicola; Scarpa, Martina; Vallotto, Marta

2017-01-01

Among the factors that affect the glass surface chemical durability, pH and complexing agents present in aqueous solution have the main role. Glass surface attack can be also related to the delamination issue causing glass particles' appearance in the pharmaceutical preparation. A few methods to check for glass containers delamination propensity and some control guidelines have been proposed. The present study emphasizes the possible synergy between a few complexing agents with pH on borosilicate glass chemical durability.Hydrolytic attack was performed in small-volume 23 mL type I glass containers autoclaved according to the European Pharmacopoeia or United States Pharmacopeia for 1 h at 121 °C, in order to enhance the chemical attack due to time, temperature, and the unfavorable surface/volume ratio. Solutions of 0.048 M or 0.024 M (M/L) of the acids citric, glutaric, acetic, EDTA (ethylenediaminetetraacetic acid), together with sodium phosphate with water for comparison, were used for the trials. The pH was adjusted ±0.05 units at fixed values 5.5, 6.6, 7, 7.4, 8, and 9 by LiOH diluted solution.Because silicon is the main glass network former, silicon release into the attack solutions was chosen as the main index of the glass surface attack and analysed by inductively coupled plasma atomic emission spectrophotometry. The work was completed by the analysis of the silicon release in the worst attack conditions of molded glass, soda lime type II glass, and tubing borosilicate glass vials to compare different glass compositions and forming technologies. Surface analysis by scanning electron microscopy was finally performed to check for the surface status after the worst chemical attack condition by citric acid. LAY ABSTRACT: Glass, like every packaging material, can have some usage limits, mainly in basic pH solutions. The issue of glass surface degradation particles that appear in vials (delamination) has forced a number of drug product recalls in recent years. To prevent such situations, pharmaceutical and biopharmaceutical manufacturers need to understand the reasons for accelerate surface glass corrosion mainly in the case of injectables.Some drugs can contain active components with known ability to corrode glass silica networks. Sometimes these ingredients are dissolved in an alkaline medium that dramatically increases the glass corrosion and potentially causes the issue. As this action is strongly affected by time and temperature, flaking may become visible only after a long storage time. The purpose of this investigation is to verify the borosilicate glass chemical durability during controlled conditions of time and temperature when in contact with testing solutions containing different complexing agents by varying the pH. Si concentration in the extract solution is taken as an index of glass dissolution during constant autoclaving conditions for 1 h at 121 °C, which simulates approximately five years of contact at room temperature.Acetate, citrate, ethylenediaminetetraacetic acid (EDTA), phosphate, and glutarate 0.048 M or 0.024 M solutions were used at increasing pH from 5.5 to 9.0. The chemical durability of two borosilicate tubing glass vials of different glass compositions were compared with the molded one in the worst attack conditions by citric acid. Even if no delamination issue has been experienced by this study in type I molded and tubing containers, the conclusions developed can provide pharmaceutical manufacturers with useful information to prevent glass delamination risk in their processes. © PDA, Inc. 2017.

A novel injection-molded capsular device for oral pulsatile delivery based on swellable/erodible polymers.

PubMed

Gazzaniga, Andrea; Cerea, Matteo; Cozzi, Alberto; Foppoli, Anastasia; Maroni, Alessandra; Zema, Lucia

2011-03-01

The feasibility of injection molding was explored in the preparation of a novel capsular device for oral pulsatile/delayed delivery based on swellable/erodible polymers. For this purpose, a mold intended to be coupled with a bench-top injection-molding press was designed. This was expected to enable the preparation of matching capsule cap and body items within a single manufacturing cycle and the selection of differing shell thicknesses (300, 600, and 900 μm). Hydroxypropylcellulose (Klucel(®) EF, LF, and GF) was employed as the release-controlling polymer in admixture with polyethylene glycol 1500 (10%, w/w) as the plasticizer. After preliminary trials aimed at the setup of operating conditions, Klucel(®) EF and LF capsule shells with satisfactory technological properties were manufactured. The performance of capsular devices filled with a tracer drug powder was studied by means of a modified USP31 disintegration apparatus. Typical in vitro delayed release patterns were thereby obtained, with lag time increasing as a function of the wall thickness. A good correlation was found between the latter parameter and t (10%), i.e., the time to 10% release, for both polymer grades employed. On the basis of the overall results, the investigated technique was proven suitable for the manufacturing of an innovative pulsatile release platform. © 2011 American Association of Pharmaceutical Scientists

Development of Maltodextrin-Based Immediate-Release Tablets Using an Integrated Twin-Screw Hot-Melt Extrusion and Injection-Molding Continuous Manufacturing Process.

PubMed

Puri, Vibha; Brancazio, Dave; Desai, Parind M; Jensen, Keith D; Chun, Jung-Hoon; Myerson, Allan S; Trout, Bernhardt L

2017-11-01

The combination of hot-melt extrusion and injection molding (HME-IM) is a promising process technology for continuous manufacturing of tablets. However, there has been limited research on its application to formulate crystalline drug-containing immediate-release tablets. Furthermore, studies that have applied the HME-IM process to molded tablets have used a noncontinuous 2-step approach. The present study develops maltodextrin (MDX)-based extrusion-molded immediate-release tablets for a crystalline drug (griseofulvin) using an integrated twin-screw HME-IM continuous process. At 10% w/w drug loading, MDX was selected as the tablet matrix former based on a preliminary screen. Furthermore, liquid and solid polyols were evaluated for melt processing of MDX and for impact on tablet performance. Smooth-surfaced tablets, comprising crystalline griseofulvin solid suspension in the amorphous MDX-xylitol matrix, were produced by a continuous process on a twin-screw extruder coupled to a horizontally opening IM machine. Real-time HME process profiles were used to develop automated HME-IM cycles. Formulation adjustments overcame process challenges and improved tablet strength. The developed MDX tablets exhibited adequate strength and a fast-dissolving matrix (85% drug release in 20 min), and maintained performance on accelerated stability conditions. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Method for making precisely configured flakes useful in optical devices

DOEpatents

Trajkovska-Petkoska, Anka [Rochester, NY; Jacobs, Stephen D [Pittsford, NY; Kosc, Tanya Z [Rochester, NY; Marshall, Kenneth L [Rochester, NY

2007-07-03

Precisely configured, especially of geometric shape, flakes of liquid crystal material are made using a mechanically flexible polymer mold with wells having shapes which are precisely configured by making the mold with a photolithographically manufactured or laser printed master. The polymer liquid crystal is poured into the wells in the flexible mold. When the liquid crystal material has solidified, the flexible mold is bent and the flakes are released and collected for use in making an electrooptical cell utilizing the liquid crystal flakes as the active element therein.

Chronic Illness Associated with Mold and Mycotoxins: Is Naso-Sinus Fungal Biofilm the Culprit?

PubMed Central

Brewer, Joseph H.; Thrasher, Jack D.; Hooper, Dennis

2013-01-01

It has recently been demonstrated that patients who develop chronic illness after prior exposure to water damaged buildings (WDB) and mold have the presence of mycotoxins, which can be detected in the urine. We hypothesized that the mold may be harbored internally and continue to release and/or produce mycotoxins which contribute to ongoing chronic illness. The sinuses are the most likely candidate as a site for the internal mold and mycotoxin production. In this paper, we review the literature supporting this concept. PMID:24368325

Chronic illness associated with mold and mycotoxins: is naso-sinus fungal biofilm the culprit?

PubMed

Brewer, Joseph H; Thrasher, Jack D; Hooper, Dennis

2013-12-24

It has recently been demonstrated that patients who develop chronic illness after prior exposure to water damaged buildings (WDB) and mold have the presence of mycotoxins, which can be detected in the urine. We hypothesized that the mold may be harbored internally and continue to release and/or produce mycotoxins which contribute to ongoing chronic illness. The sinuses are the most likely candidate as a site for the internal mold and mycotoxin production. In this paper, we review the literature supporting this concept.

Onychomycosis due to opportunistic molds*

PubMed Central

Martínez-Herrera, Erick Obed; Arroyo-Camarena, Stefanie; Tejada-García, Diana Luz; Porras-López, Carlos Francisco; Arenas, Roberto

2015-01-01

BACKGROUND: Onychomycosis are caused by dermatophytes and Candida, but rarely by non- dermatophyte molds. These opportunistic agents are filamentous fungi found as soil and plant pathogens. OBJECTIVES: To determine the frequency of opportunistic molds in onychomycosis. METHODS: A retrospective analysis of 4,220 cases with onychomycosis, diagnosed in a 39-month period at the Institute of Dermatology and Skin surgery "Prof. Dr. Fernando A. Cordero C." in Guatemala City, and confirmed with a positive KOH test and culture. RESULTS: 32 cases (0.76%) of onychomycosis caused by opportunistic molds were confirmed. The most affected age group ranged from 41 to 65 years (15 patients, 46.9%) and females were more commonly affected (21 cases, 65.6%) than males. Lateral and distal subungual onychomycosis (OSD-L) was detected in 20 cases (62.5%). The microscopic examination with KOH showed filaments in 19 cases (59.4%), dermatophytoma in 9 cases (28.1%), spores in 2 cases (6.25%), and filaments and spores in 2 cases (6.25%). Etiologic agents: Aspergillus sp., 11 cases (34.4%); Scopulariopsis brevicaulis, 8 cases (25.0%); Cladosporium sp., 3 cases (9.4%); Acremonium sp., 2 cases (6.25%); Paecilomyces sp., 2 cases (6.25%); Tritirachium oryzae, 2 cases (6.25%); Fusarium sp., Phialophora sp., Rhizopus sp. and Alternaria alternate, 1 case (3.1%) each. CONCLUSIONS: We found onychomycosis by opportunistic molds in 0.76% of the cases and DLSO was present in 62.5%. The most frequent isolated etiological agents were: Aspergillus sp. and Scopulariopsis brevicaulis. PMID:26131862

ANIMAL MODELS OF MOLD ALLERGY

EPA Science Inventory

The concept of molds as causative agents for allergy/asthma is not new. In fact many fungal genera have been associated with allergic lung disease, but only a few fungi are well studied and even fewer fungal allergens well characterized. The complexity and variety of fungal pro...

Fiber-Reinforced Epoxy Composites and Methods of Making Same Without the Use of Oven or Autoclave

NASA Technical Reports Server (NTRS)

Barnell, Thomas J. (Inventor); Rauscher, Michael D. (Inventor); Stienecker, Rick D. (Inventor); Nickerson, David M. (Inventor); Tong, Tat H. (Inventor)

2016-01-01

Method embodiments for producing a fiber-reinforced epoxy composite comprise providing a mold defining a shape for a composite, applying a fiber reinforcement over the mold, covering the mold and fiber reinforcement thereon in a vacuum enclosure, performing a vacuum on the vacuum enclosure to produce a pressure gradient, insulating at least a portion of the vacuum enclosure with thermal insulation, infusing the fiber reinforcement with a reactive mixture of uncured epoxy resin and curing agent under vacuum conditions, wherein the reactive mixture of uncured epoxy resin and curing agent generates exothermic heat, and producing the fiber-reinforced epoxy composite having a glass transition temperature of at least about 100.degree. C. by curing the fiber reinforcement infused with the reactive mixture of uncured epoxy resin and curing agent by utilizing the exothermically generated heat, wherein the curing is conducted inside the thermally insulated vacuum enclosure without utilization of an external heat source or an external radiation source.

Attributes of Stachybotrys chartarum and its association with human disease.

PubMed

Hossain, Mohammad Ashraf; Ahmed, Mohamed Sotohy; Ghannoum, Mahmoud Afif

2004-02-01

Mold contamination and toxicities are not limited to crops and animals; they are also a concern in human health. Molds occur in outdoor and indoor environments, and water-damaged buildings harbor and provide substrate for several mold species. Of these, Stachybotrys chartarum poses a particular threat to occupants. Patients with building-related symptoms and infant idiopathic pulmonary hemorrhage often have histories of living in moldy, water-damaged buildings. Although a causal connection is far from being unequivocally proven, S. chartarum has been associated with such clinical conditions. These illnesses could be attributed in part to mycotoxins released by S. chartarum. Recently, a hemolysin released by this mold was found to be hemolytic in vitro and in vivo. In addition, allergenic proteins have been characterized from S. chartarum. The exact mechanism of S. chartarum pathogenesis has not yet been defined. Moreover, a causality-effect relation is not yet established. This review summarizes available information on the pathogenic attributes of S. chartarum and calls for well-controlled objective studies.

Occurrence of fludioxonil resistance in penicillium digitatum from citrus in California

USDA-ARS?s Scientific Manuscript database

Penicillium digitatum is the causal agent of green mold, the most important postharvest disease of citrus (Citrus spp.). Fludioxonil is marketed as either a solo product or in combination with azoxystrobin for control of green mold and other postharvest diseases. Baseline sensitivity to fludioxonil ...

Thermal expansion of an epoxy-glass microsphere composite

NASA Technical Reports Server (NTRS)

Price, H. L.; Burks, H. D.

1977-01-01

The thermal expansion of a composite of epoxy (diglycidyl ether of bisphenol A) and solid glass microspheres was investigated. The microspheres had surfaces which were either untreated or treated with a silicone release agent, an epoxy coupling agent, or a general purpose silane coupling agent. Both room temperature (about 300 K) and elevated temperature (about 475 K) cures were used for the epoxy. Two microsphere size ranges were used, about 50 microns, which is applicable in filled moldings, and about 125 microns, which is applicable as bond line spacers. The thermal expansion of the composites was measured from 300 to 350 K or from 300 to 500 K, depending on the epoxy cure temperature. Measurements were made on composites containing up to .6 volume fraction microspheres. Two predictive models, which required only the values of thermal expansion of the polymer and glass and their specific gravities, were tested against the experimental data. A finite element analysis was made of the thermal strain of a composite cell containing a single microsphere surrounded by a finite-thickness interface.

ELISA MEASUREMENT OF STACHYLYSIN (TM) IN SERUM TO QUANTIFY HUMAN EXPOSURES TO THE INDOOR MOLD STACHYBOTRYS CHARTARUM

EPA Science Inventory

Antibodies were produced against the hemolytic agent stachylysin obtained from the mold Stachybotryis chartarum. These antibodies were used to develop two enzyme-linked immunosorbent assay (ELISA) methods for the analysis of stachylysin in human and rat sera and environmental sa...

The preparation of steatite suspension for spray drying

NASA Technical Reports Server (NTRS)

Jirousek, L.; Spicak, K.

1983-01-01

Liquifying agents were investigated for preparation of highly concentrated steatite suspensions which are to be spray-dried. Organic additives for improving the molding properties and strength of green compacts are described. Demands on properties of the spray-dried granules are defined with regard to shrinkage of the molded compacts.

ELISA MEASUREMENT OF STACHYLYSIN IN SERUM TO QUANTIFY HUMAN EXPOSURES TO THE INDOOR MOLD STACHYBOTRYS CHARTARUM

EPA Science Inventory

Problem- To develop a measurable indicator of human exposure to Stachybotys chartarum.

Methods- Antibodies were produced against the hemolytic agent stachylysin obtained from the mold S. chartarum. These antibodies were used to develop two enzyme-linked immunosorbent ass...

Accelerated Colorimetric Micro-assay for Screening Mold Inhibitors

Treesearch

Carol A. Clausen; Vina W. Yang

2014-01-01

Rapid quantitative laboratory test methods are needed to screen potential antifungal agents. Existing laboratory test methods are relatively time consuming, may require specialized test equipment and rely on subjective visual ratings. A quantitative, colorimetric micro-assay has been developed that uses XTT tetrazolium salt to metabolically assess mold spore...

Seasonal Allergies (Hay Fever)

MedlinePlus

... usually when outdoor molds release their spores, and trees, grasses, and weeds release tiny pollen particles into ... happen. For example, in the mid-Atlantic states, tree pollination is February through May, grass pollen runs ...

Fabrication of high-transmission microporous membranes by proton beam writing-based molding technique

NASA Astrophysics Data System (ADS)

Wang, Liping; Meyer, Clemens; Guibert, Edouard; Homsy, Alexandra; Whitlow, Harry J.

2017-08-01

Porous membranes are widely used as filters in a broad range of micro and nanofluidic applications, e.g. organelle sorters, permeable cell growth substrates, and plasma filtration. Conventional silicon fabrication approaches are not suitable for microporous membranes due to the low mechanical stability of thin film substrates. Other techniques like ion track etching are limited to the production of randomly distributed and randomly orientated pores with non-uniform pore sizes. In this project, we developed a procedure for fabricating high-transmission microporous membranes by proton beam writing (PBW) with a combination of spin-casting and soft lithography. In this approach, focused 2 MeV protons were used to lithographically write patterns consisting of hexagonal arrays of high-density pillars of few μm size in a SU-8 layer coated on a silicon wafer. After development, the pillars were conformably coated with a thin film of poly-para-xylylene (Parylene)-C release agent and spin-coated with polydimethylsiloxane (PDMS). To facilitate demolding, a special technique based on the use of a laser-cut sealing tape ring was developed. This method facilitated the successful delamination of 20-μm thick PDMS membrane with high-density micropores from the mold without rupture or damage.

Weight loss by Ppc-1, a novel small molecule mitochondrial uncoupler derived from slime mold.

PubMed

Suzuki, Toshiyuki; Kikuchi, Haruhisa; Ogura, Masato; Homma, Miwako K; Oshima, Yoshiteru; Homma, Yoshimi

2015-01-01

Mitochondria play a key role in diverse processes including ATP synthesis and apoptosis. Mitochondrial function can be studied using inhibitors of respiration, and new agents are valuable for discovering novel mechanisms involved in mitochondrial regulation. Here, we screened small molecules derived from slime molds and other microorganisms for their effects on mitochondrial oxygen consumption. We identified Ppc-1 as a novel molecule which stimulates oxygen consumption without adverse effects on ATP production. The kinetic behavior of Ppc-1 suggests its function as a mitochondrial uncoupler. Serial administration of Ppc-1 into mice suppressed weight gain with no abnormal effects on liver or kidney tissues, and no evidence of tumor formation. Serum fatty acid levels were significantly elevated in mice treated with Ppc-1, while body fat content remained low. After a single administration, Ppc-1 distributes into various tissues of individual animals at low levels. Ppc-1 stimulates adipocytes in culture to release fatty acids, which might explain the elevated serum fatty acids in Ppc-1-treated mice. The results suggest that Ppc-1 is a unique mitochondrial regulator which will be a valuable tool for mitochondrial research as well as the development of new drugs to treat obesity.

Enteric-coating of pulsatile-release HPC capsules prepared by injection molding.

PubMed

Macchi, E; Zema, L; Maroni, A; Gazzaniga, A; Felton, L A

2015-04-05

Capsular devices based on hydroxypropyl cellulose (Klucel® LF) intended for pulsatile release were prepared by injection molding (IM). In the present work, the possibility of exploiting such capsules for the development of colonic delivery systems based on a time-dependent approach was evaluated. For this purpose, it was necessary to demonstrate the ability of molded cores to undergo a coating process and that coated systems yield the desired performance (gastric resistance). Although no information was available on the coating of IM substrates, some issues relevant to that of commercially-available capsules are known. Thus, preliminary studies were conducted on molded disks for screening purposes prior to the spray-coating of HPC capsular cores with Eudragit® L 30 D 55. The ability of the polymeric suspension to wet the substrate, spread, start penetrating and initiate hydration/swelling, as well as to provide a gastroresistant barrier was demonstrated. The coating of prototype HPC capsules was carried out successfully, leading to coated systems with good technological properties and able to withstand the acidic medium with no need for sealing at the cap/body joint. Such systems maintained the original pulsatile release performance after dissolution of the enteric film in pH 6.8 fluid. Therefore, they appeared potentially suitable for the development of a colon delivery platform based on a time-dependent approach. Copyright © 2015 Elsevier B.V. All rights reserved.

Host ranges of Penicillium species causing blue mold of bulb crops in Washington State and Idaho

USDA-ARS?s Scientific Manuscript database

First reported from the Pacific Northwest (PNW) of U.S.A. as causal agents of blue mold on edible and/or ornamental bulbs are Penicillium albocoremium (from Tulipa sp.; pathogenic on Allium sativum, A. cepa, A. stipitatum, Iris hollandica and Tulipa sp.), P. crustosum (from Narcissus; pathogenic on ...

Residential Culturable Fungi, (1–3, 1–6)-β-D-glucan, and Ergosterol Concentrations in Dust Are Not Associated with Asthma, Rhinitis or Eczema Diagnoses in Children

PubMed Central

Choi, Hyunok; Byrne, Sam; Larsen, Lisbeth Suldrup; Sigsgaard, Torben; Thorne, Peter S.; Larsson, Lennart; Sebastian, Aleksandra; Bornehag, Carl-Gustaf

2014-01-01

Background Qualitative reporting of home indoor moisture problems predicts respiratory diseases. However, causal agents underlying such qualitative markers remain unknown. Methods In the homes of 198 multiple allergic case children and 202 controls in Sweden, we cultivated culturable fungi by directly plating dust, and quantified(1–3, 1–6)-β-D-glucan, and ergosterol in dust samples from the child’s bedroom. We examined the relationship between these fungal agents and degree of parent or inspector reported home indoor dampness, and microbiological laboratory’s mold index. We also compared the concentrations of these agents between multiple allergic cases and healthy controls, as well as IgE-sensitization among cases. Results The concentrations of culturable fungal agents were comparable between houses with parent and inspector reported mold issues and those without. There were no differences in concentrations of the individual or the total summed culturable fungi, (1–3, 1–6)-β-D-glucan, and ergosterol between the controls and the multiple allergic case children, or individual diagnosis of asthma, rhinitis or eczema. Conclusion Culturable fungi, (1–3, 1–6)-β-D-glucan, and ergosterol in dust were not associated with qualitative markers of indoor dampness or mold or indoor humidity. Furthermore, these agents in dust samples were not associated with any health outcomes in the children. PMID:24016225

Chitosan-containing bread made using marine shellfishery byproducts: functional, bioactive, and quality assessment of the end product.

PubMed

Lafarga, Tomas; Gallagher, Eimear; Walsh, Des; Valverde, Juan; Hayes, Maria

2013-09-18

Chitosan is nature's second most abundant polymer after cellulose and forms the structural support in crustacean shell material and Basidomycete mushroom stalks. Chitosan is a known antimicrobial agent but, to date, was not examined as an antimicrobial agent in bread formulations for the prevention of mold or rope formation. The aim of this work was to investigate the effects of chitosan generated from prawn shell byproducts on the color, moisture, and texture and crumb formation of bread. A secondary aim of this work was to determine the antimicrobial effect of chitosan added to bread at a rate of 1% against the rope spoilage pathogen Bacillus cereus along with natural molds. The addition of chitosan to bread with a molecular mass of 124000 ± 10000 g/mol and 19% deacetylated was found to inhibit B. cereus growth and rope formation in bread when monitored over 3-5 days. Natural mold growth was also significantly delayed in bread made using chitosan substitution of flour at 1% compared to the control bread, where mold was observed growing on the bread surface after 72 h when bread was incubated at 30 °C.

Effect of processing method on the mechanical and thermal of Silvergrass/HDPE composites

NASA Astrophysics Data System (ADS)

Liu, Bing; Jin, Yueqiang; Wang, Shuying

2017-05-01

This paper investigates the effect of compression and injection molding methods on properties of Silvergrass-HDPE (High Density Polyethylene) composites, with respect to mechanical behaviors. Maleated polyethylene (MAPE) was added in the composite and improved the mechanical property of the composite. The research founds MAPE can improve the mechanical property because it improved the interfacial compatibility as a coupling agent. When added a content of 8% of MAPE, Silvergrass-HDPE composites made from compression molding shows a better mechanical performance in tensile strength and flexural strength than that made from injection molding, with increasing Silvergrass fiber content from 30% to 50%. However, the WPCs (wood plastics composites) made from injection molding had a lower degree of crystallinity with or without MAPE treatment.

Acceleration of robust "biotube" vascular graft fabrication by in-body tissue architecture technology using a novel eosin Y-releasing mold.

PubMed

Nakayama, Yasuhide; Tsujinaka, Takahiro

2014-02-01

A novel eosin Y-releasing mold was designed to accelerate the fabrication of in vivo tissue engineered autologous vascular prosthetic tissues, called the "biotubes." The mold was prepared by addition of an aqueous solution of eosin Y (1∼6 w/v%) to the agar gel (0.3%), which was attached to the luminal surface of the microporous acrylate tube (diameter, 5 mm; length, 28 mm; pore size, 0.5 mmϕ). The eosin Y release period was controlled by the number of pores (3∼160). On embedding the molds into dorsal, subcutaneous pouches of rats for 1 week, completely encapsulated biotubes, mainly consisting of collagen, with thick walls (418.2 ± 173.4 μm) and robust mechanical properties (elastic modulus, 956.2 ± 196.5 kPa; burst pressure 5850 ± 2383 mmHg) were formed. These values were, respectively, more than 4.3, 3.8, and 5.6 times greater than the corresponding controls (acrylate rods). The high elastic modulus of the biotubes was obtained even with a small number of micropores (3), and a low concentration of eosin Y (1%) within a very short embedding period (5 days), irrespective of rat weights. This innovative method for rapid production of vascular grafts with thick walls and robust mechanical properties may be adaptable for the sub-emergency clinical use of biotubes in regenerative medicine. Copyright © 2013 Wiley Periodicals, Inc.

Injection molding as a one-step process for the direct production of pharmaceutical dosage forms from primary powders.

PubMed

Eggenreich, K; Windhab, S; Schrank, S; Treffer, D; Juster, H; Steinbichler, G; Laske, S; Koscher, G; Roblegg, E; Khinast, J G

2016-05-30

The objective of the present study was to develop a one-step process for the production of tablets directly from primary powder by means of injection molding (IM), to create solid-dispersion based tablets. Fenofibrate was used as the model API, a polyvinyl caprolactame-polyvinyl acetate-polyethylene glycol graft co-polymer served as a matrix system. Formulations were injection-molded into tablets using state-of-the-art IM equipment. The resulting tablets were physico-chemically characterized and the drug release kinetics and mechanism were determined. Comparison tablets were produced, either directly from powder or from pre-processed pellets prepared via hot melt extrusion (HME). The content of the model drug in the formulations was 10% (w/w), 20% (w/w) and 30% (w/w), respectively. After 120min, both powder-based and pellet-based injection-molded tablets exhibited a drug release of 60% independent of the processing route. Content uniformity analysis demonstrated that the model drug was homogeneously distributed. Moreover, analysis of single dose uniformity also revealed geometric drug homogeneity between tablets of one shot. Copyright © 2016 Elsevier B.V. All rights reserved.

DIRECT INGOT PROCESS FOR PRODUCING URANIUM

DOEpatents

Leaders, W.M.; Knecht, W.S.

1960-11-15

A process is given in which uranium tetrafluoride is reduced to the metal with magnesium and in the same step the uranium metal formed is cast into an ingot. For this purpose a mold is arranged under and connected with the reaction bomb, and both are filled with the reaction mixture. The entire mixture is first heated to just below reaction temperature, and thereafter heating is restricted to the mixture in the mold. The reaction starts in the mold whereby heat is released which brings the rest of the mixture to reaction temperature. Pure uranium metal settles in the mold while the magnesium fluoride slag floats on top of it. After cooling, the uranium is separated from the slag by mechanical means.

Demonstration of pharmaceutical tablet coating process by injection molding technology.

PubMed

Puri, Vibha; Brancazio, David; Harinath, Eranda; Martinez, Alexander R; Desai, Parind M; Jensen, Keith D; Chun, Jung-Hoon; Braatz, Richard D; Myerson, Allan S; Trout, Bernhardt L

2018-01-15

We demonstrate the coating of tablets using an injection molding (IM) process that has advantage of being solvent free and can provide precision coat features. The selected core tablets comprising 10% w/w griseofulvin were prepared by an integrated hot melt extrusion-injection molding (HME-IM) process. Coating trials were conducted on a vertical injection mold machine. Polyethylene glycol and polyethylene oxide based hot melt extruded coat compositions were used. Tablet coating process feasibility was successfully demonstrated using different coating mold designs (with both overlapping and non-overlapping coatings at the weld) and coat thicknesses of 150 and 300 μm. The resultant coated tablets had acceptable appearance, seal at the weld, and immediate drug release profile (with an acceptable lag time). Since IM is a continuous process, this study opens opportunities to develop HME-IM continuous processes for transforming powder to coated tablets. Copyright © 2017 Elsevier B.V. All rights reserved.

Thermoplastic polyurethanes for the manufacturing of highly dosed oral sustained release matrices via hot melt extrusion and injection molding.

PubMed

Claeys, Bart; Vervaeck, Anouk; Hillewaere, Xander K D; Possemiers, Sam; Hansen, Laurent; De Beer, Thomas; Remon, Jean Paul; Vervaet, Chris

2015-02-01

This study evaluated thermoplastic polyurethanes (TPUR) as matrix excipients for the production of oral solid dosage forms via hot melt extrusion (HME) in combination with injection molding (IM). We demonstrated that TPURs enable the production of solid dispersions - crystalline API in a crystalline carrier - at an extrusion temperature below the drug melting temperature (Tm) with a drug content up to 65% (wt.%). The release of metoprolol tartrate was controlled over 24h, whereas a complete release of diprophylline was only possible in combination with a drug release modifier: polyethylene glycol 4000 (PEG 4000) or Tween 80. No burst release nor a change in tablet size and geometry was detected for any of the formulations after dissolution testing. The total matrix porosity increased gradually upon drug release. Oral administration of TPUR did not affect the GI ecosystem (pH, bacterial count, short chain fatty acids), monitored via the Simulator of the Human Intestinal Microbial Ecosystem (SHIME). The high drug load (65 wt.%) in combination with (in vitro and in vivo) controlled release capacity of the formulations, is noteworthy in the field of formulations produced via HME/IM. Copyright © 2014 Elsevier B.V. All rights reserved.

Human Abuse Potential of an Abuse-Deterrent (AD), Extended-Release (ER) Morphine Product Candidate (Morphine-ADER Injection-Molded Tablets) versus Extended-Release Morphine Administered Orally in Nondependent Recreational Opioid Users

PubMed Central

Webster, Lynn R.; Lawler, John; Lindhardt, Karsten; Dayno, Jeffrey M.

2017-01-01

Objective. To compare the relative human abuse potential of intact and manipulated morphine abuse-deterrent, extended-release injection-molded tablets (morphine-ADER-IMT) with that of marketed morphine sulfate ER tablets Methods. This randomized, double-blind, triple-dummy, active- and placebo-controlled, 4-way crossover, single-center study included adult volunteers who were experienced, nondependent, recreational opioid users. Participants were randomized 1:1:1:1 to placebo, morphine-ADER-IMT (60 mg, intact), morphine-ADER-IMT (60 mg, manipulated), and morphine ER (60 mg, manipulated) and received 1 dose of each oral agent in crossover fashion, separated by ≥5 days. Pharmacodynamic and pharmacokinetic endpoints were assessed, including the primary endpoint of peak effect of Drug Liking (Emax) via Drug Liking Visual Analog Scale (VAS) score and the secondary endpoints of time to Emax (TEmax) and mean abuse quotient (AQ; a pharmacokinetic parameter associated with drug liking). Results. Thirty-eight participants completed the study. Median Drug Liking VAS Emax was significantly lower after treatment with manipulated morphine-ADER-IMT (67) compared with manipulated morphine ER (74; P = 0.007). TEmax was significantly shorter after treatment with manipulated morphine ER compared with intact (P < 0.0001) or manipulated (P = 0.004) morphine-ADER-IMT. Mean AQ was lower after treatment with intact (5.7) or manipulated (16.4) morphine-ADER-IMT compared with manipulated morphine ER (45.9). Conclusions. Manipulated morphine-ADER-IMT demonstrated significantly lower Drug Liking Emax compared with manipulated morphine ER when administered orally. Morphine-ADER-IMT would be an important new AD, ER morphine product with lower potential for unintentional misuse by chewing or intentional manipulation for oral abuse than currently available non-AD morphine ER products. PMID:27633773

Preparation of Drug-loaded Chitosan Microspheres and Its Application in Paper-based PVC Wallpaper

NASA Astrophysics Data System (ADS)

Lin, Hui; Chen, Lihui; Yan, Guiyang; Chen, Feng; Huang, Liulian

2018-03-01

By screening through test, it was found that the drug-loaded chitosan microspheres with the average particle size of 615 nm may be prepared with NaF as the mold-proof drug, chitosan as the drug carrier and sodium tripolyphosphate as the cross-linking agent; and they can improve the aspergillus niger-proof effect if loaded onto the base paper surface of the paper-based PVC wallpaper. The results show that NaF and chitosan have mold-proof synergistic effects; the mold-proof effect of the wallpaper may be improved by increasing the dose of chitosan; when the mass ratio of NaF, sodium tripolyphosphate and chitosan was 2:7:28, the paper-based PVC wallpaper with good mold-proof property can be prepared.

Overcoming the Fundamental Challenges in Improving the Impact Strength and Crystallinity of PLA Biocomposites: Influence of Nucleating Agent and Mold Temperature.

PubMed

Nagarajan, Vidhya; Zhang, Kunyu; Misra, Manjusri; Mohanty, Amar K

2015-06-03

Poly(lactic acid) (PLA), one of the widely studied renewable resource based biopolymers, has yet to gain a strong commercial standpoint because of certain property limitations. This work is a successful attempt in achieving PLA biocomposites that showed concurrent improvements in impact strength and heat deflection temperature (HDT). Biocomposites were fabricated from a super toughened ternary blend of PLA, poly(ether-b-amide) elastomeric copolymer and ethylene-methyl acrylate-glycidyl methacrylate and miscanthus fibers. The effects of varying the processing parameters and addition of various nucleating agents were investigated. Crystallinity was controlled by optimizing the mold temperature and cycle time of the injection process. With the addition of 1 wt % aromatic sulfonate derivative (Lak-301) as a nucleating agent at a mold temperature of 110 °C, PLA biocomposites exhibited dramatic reduction in crystallization half time to 1.3 min with crystallinity content of 42%. Mechanical and thermal properties assessment for these biocomposites revealed a 4-fold increase in impact strength compared to neat PLA. The HDT of PLA biocomposites increased to 85 °C from 55 °C compared to neat PLA. Crystallization behavior was studied in detail using differential scanning calorimetry and was supported with observations from wide-angle X-ray diffraction profiles and polarized optical microscopy. The presence of a nucleating agent did not alter the crystal structure of PLA; however, a significant difference in spherulite size, crystallization rate and content was observed. Fracture surface morphology and distribution of nucleating agent in the PLA biocomposites were investigated through scanning electron microscopy.

Weight Loss by Ppc-1, a Novel Small Molecule Mitochondrial Uncoupler Derived from Slime Mold

PubMed Central

Suzuki, Toshiyuki; Kikuchi, Haruhisa; Ogura, Masato; Homma, Miwako K.; Oshima, Yoshiteru; Homma, Yoshimi

2015-01-01

Mitochondria play a key role in diverse processes including ATP synthesis and apoptosis. Mitochondrial function can be studied using inhibitors of respiration, and new agents are valuable for discovering novel mechanisms involved in mitochondrial regulation. Here, we screened small molecules derived from slime molds and other microorganisms for their effects on mitochondrial oxygen consumption. We identified Ppc-1 as a novel molecule which stimulates oxygen consumption without adverse effects on ATP production. The kinetic behavior of Ppc-1 suggests its function as a mitochondrial uncoupler. Serial administration of Ppc-1 into mice suppressed weight gain with no abnormal effects on liver or kidney tissues, and no evidence of tumor formation. Serum fatty acid levels were significantly elevated in mice treated with Ppc-1, while body fat content remained low. After a single administration, Ppc-1 distributes into various tissues of individual animals at low levels. Ppc-1 stimulates adipocytes in culture to release fatty acids, which might explain the elevated serum fatty acids in Ppc-1-treated mice. The results suggest that Ppc-1 is a unique mitochondrial regulator which will be a valuable tool for mitochondrial research as well as the development of new drugs to treat obesity. PMID:25668511

A molded surface-micromachining and bulk etching release (MOSBE) fabrication platform on (1 1 1) Si for MOEMS

NASA Astrophysics Data System (ADS)

Wu, Mingching; Fang, Weileun

2006-02-01

This work attempts to integrate poly-Si thin film and single-crystal-silicon (SCS) structures in a monolithic process. The process integrated multi-depth DRIE (deep reactive ion etching), trench-refilled molding, a two poly-Si MUMPs process and (1 1 1) Si bulk micromachining to accomplish multi-thickness and multi-depth structures for superior micro-optical devices. In application, a SCS scanning mirror driven by self-aligned vertical comb-drive actuators was demonstrated. The stiffness of the mirror was significantly increased by thick SCS structures. The thin poly-Si film served as flexible torsional springs and electrical routings. The depth difference of the vertical comb electrodes was tuned by DRIE to increase the devices' stroke. Finally, a large moving space was available after the bulk Si etching. In summary, the present fabrication process, named (1 1 1) MOSBE (molded surface-micromachining and bulk etching release on (1 1 1) Si substrate), can further integrate with the MUMPs devices to establish a more powerful platform.

Transparent ceramics and methods of preparation thereof

DOEpatents

Hollingsworth, Joel P.; Kuntz, Joshua D.; Seeley, Zachary M.; Soules, Thomas F.

2012-12-25

A method for forming a transparent ceramic preform in one embodiment includes forming a suspension of oxide particles in a solvent, wherein the suspension includes a dispersant, with the proviso that the suspension does not include a gelling agent; and uniformly curing the suspension for forming a preform of gelled suspension. A method according to another embodiment includes creating a mixture of inorganic particles, a solvent and a dispersant, the inorganic particles having a mean diameter of less than about 2000 nm; agitating the mixture; adding the mixture to a mold; and curing the mixture in the mold for gelling the mixture, with the proviso that no gelling agent is added to the mixture.

Bag molding processes

NASA Astrophysics Data System (ADS)

Slobodzinsky, A.

Features, materials, and techniques of vacuum, pressure, and autoclave FRP bag molding processes are described. The bags are used in sealed environments, inflated to flexibly force a curing FRP laminate to conform to a stiff mold form which defines the shape of the finished product. Densification is achieved as the bag presses out the voids and excess resin from the laminate, and consolidation occurs as the plies and adherends are bonded by the bag pressure. Curing techniques nominally involved room temperature or high temperature, and investigations of alternative techniques, such as induction, dielectric, microwave, xenon flash, UV, electron beam, and gamma radiation heating are proceeding. Polysulfone is the most common thermoplastic. Details are given of mold preparations, peel plies or release films and fabrics, bagging techniques, and reusable venting blankets and silicone rubber bags.

Mold and Human Health: a Reality Check.

PubMed

Borchers, Andrea T; Chang, Christopher; Eric Gershwin, M

2017-06-01

There are possibly millions of mold species on earth. The vast majority of these mold spores live in harmony with humans, rarely causing disease. The rare species that does cause disease does so by triggering allergies or asthma, or may be involved in hypersensitivity diseases such as allergic bronchopulmonary aspergillosis or allergic fungal sinusitis. Other hypersensitivity diseases include those related to occupational or domiciliary exposures to certain mold species, as in the case of Pigeon Breeder's disease, Farmer's lung, or humidifier fever. The final proven category of fungal diseases is through infection, as in the case of onchomycosis or coccidiomycosis. These diseases can be treated using anti-fungal agents. Molds and fungi can also be particularly important in infections that occur in immunocompromised patients. Systemic candidiasis does not occur unless the individual is immunodeficient. Previous reports of "toxic mold syndrome" or "toxic black mold" have been shown to be no more than media hype and mass hysteria, partly stemming from the misinterpreted concept of the "sick building syndrome." There is no scientific evidence that exposure to visible black mold in apartments and buildings can lead to the vague and subjective symptoms of memory loss, inability to focus, fatigue, and headaches that were reported by people who erroneously believed that they were suffering from "mycotoxicosis." Similarly, a causal relationship between cases of infant pulmonary hemorrhage and exposure to "black mold" has never been proven. Finally, there is no evidence of a link between autoimmune disease and mold exposure.

Effect of boron compounds on physical, mechanical, and fire properties of injection molded wood plastic composites

Treesearch

Nadir Ayrilmis; Turgay Akbulut; Turker Dundar; Robert H. White; Fatih Mengeloglu; Zeki Candan; Umit Buyuksari; Erkan Avci

2011-01-01

Physical, mechanical, and fire properties of the injection-molded wood flour/polypropylene composites (WPCs) incorporated with different levels of boron compounds, borax/boric acid (BX/BA) (0.5:0.5 wt %) and zinc borate (ZB) (4, 8, or 12 wt %) were investigated. The effect of the coupling agent loading (2, 4, or 6 wt %), maleic anhydride-grafted PP (MAPP), on the...

Is Mold Toxicity Really a Problem for Our Patients? Part 2—Nonrespiratory Conditions

PubMed Central

Pizzorno, Joseph; Shippy, Ann

2016-01-01

In my last editorial, I addressed the respiratory effects of mold exposure. The surprising research shows that as many as 50% of residential and work environments have water damage1 and that mold toxicity should be considered in all patients with any chronic respiratory condition. This is especially true in adult-onset asthma, two-thirds of which appears to be caused by toxins released from water-damaged buildings. The carcinogenic effects of food-borne mold contamination are also well documented. Less clear is the role of indoor mold exposure in water-damaged buildings and its relationship to nonrespiratory conditions. As we look at the research on mold toxicity and toxins in general, we propose that the medical community (by all its names) has focused too much on the “yellow canaries” and missed the big picture that toxins have now become a primary driver of disease in the general population, not only among those most susceptible. The mold toxicity conundrum illustrates this issue quite well. As summarized in this editorial, there clearly is a portion of the population, the size of which is currently unknown, who experience neurological and/or immunological damage from mold toxicity. In addition, a substantial portion of the population experiences chronic respiratory problems from mold exposure. This does not mean we should stop paying attention to our more affected patients. Rather, we need to realize that almost everyone is being affected by toxins to some degree: molds, metals, solvents, persistent organic pollutants, etc. PMID:27547160

Is Mold Toxicity Really a Problem for Our Patients? Part 2-Nonrespiratory Conditions.

PubMed

Pizzorno, Joseph; Shippy, Ann

2016-06-01

In my last editorial, I addressed the respiratory effects of mold exposure. The surprising research shows that as many as 50% of residential and work environments have water damage1 and that mold toxicity should be considered in all patients with any chronic respiratory condition. This is especially true in adult-onset asthma, two-thirds of which appears to be caused by toxins released from water-damaged buildings. The carcinogenic effects of food-borne mold contamination are also well documented. Less clear is the role of indoor mold exposure in water-damaged buildings and its relationship to nonrespiratory conditions. As we look at the research on mold toxicity and toxins in general, we propose that the medical community (by all its names) has focused too much on the "yellow canaries" and missed the big picture that toxins have now become a primary driver of disease in the general population, not only among those most susceptible. The mold toxicity conundrum illustrates this issue quite well. As summarized in this editorial, there clearly is a portion of the population, the size of which is currently unknown, who experience neurological and/or immunological damage from mold toxicity. In addition, a substantial portion of the population experiences chronic respiratory problems from mold exposure. This does not mean we should stop paying attention to our more affected patients. Rather, we need to realize that almost everyone is being affected by toxins to some degree: molds, metals, solvents, persistent organic pollutants, etc.

Significance of air humidity and air velocity for fungal spore release into the air

NASA Astrophysics Data System (ADS)

Pasanen, A.-L.; Pasanen, P.; Jantunen, M. J.; Kalliokoski, P.

Our previous field studies have shown that the presence of molds in buildings does not necessarily mean elevated airborne spore counts. Therefore, we investigated the release of fungal spores from cultures of Aspergillus fumigatus, Penicillium sp. and Cladosporium sp. at different air velocities and air humidities. Spores of A. fumigatus and Penicillium sp. were released from conidiophores already at air velocity of 0.5 ms -1, whereas Cladosporium spores required at least a velocity of 1.0 ms -1. Airborne spore counts of A. fumigatus and Penicillium sp. were usually higher in dry than moist air, being minimal at relative humidities (r.h.) above 70%, while the effect of r.h. on the release of Cladosporium sp. was ambivalent. The geometric mean diameter of released spores increased when the r.h. exceeded a certain level which depends on fungal genus. Thus, spores of all three fungi were hygroscopic but the hygroscopicity of various spores appeared at different r.h.-ranges. This study indicates that spore release is controlled by external factors and depends on fungal genus which can be one reason for considerable variation of airborne spore counts in buildings with mold problems.

Proinflammatory cytokines and response to molds in mononuclear cells of patients with Meniere disease.

PubMed

Frejo, Lidia; Gallego-Martinez, Alvaro; Requena, Teresa; Martin-Sanz, Eduardo; Amor-Dorado, Juan Carlos; Soto-Varela, Andres; Santos-Perez, Sofia; Espinosa-Sanchez, Juan Manuel; Batuecas-Caletrio, Angel; Aran, Ismael; Fraile, Jesus; Rossi-Izquierdo, Marcos; Lopez-Escamez, Jose Antonio

2018-04-13

Epidemiological studies have found a higher prevalence of allergic symptoms and positive prick tests in patients with Meniere's disease (MD); however the effect of allergenic extracts in MD has not been established. Thus, this study aims to determine the effect of Aspergillus and Penicillium stimulation in cytokine release and gene expression profile in MD. Patients with MD showed higher basal levels of IL-1β, IL-1RA, IL-6 and TNF-α when compared to healthy controls. We observed that IL-1β levels had a bimodal distribution suggesting two different subgroups of patients, with low and high basal levels of cytokines. Gene expression profile in peripheral blood mononuclear cells (PBMC) showed significant differences in patients with high and low basal levels of IL-1β. We found that both mold extracts triggered a significant release of TNF-α in MD patients, which were not found in controls. Moreover, after mold stimulation, MD patients showed a different gene expression profile in PBMC, according to the basal levels of IL-1β. The results indicate that a subset of MD patients have higher basal levels of proinflammatory cytokines and the exposure to Aspergillus and Penicillium extracts may trigger additional TNF-α release and contribute to exacerbate inflammation.

Explosive Testing of Class 1.3 Rocket Booster Propellant

DTIC Science & Technology

1994-08-01

molds were lined with 0.025 mm (0.001 in.) Velostat conductive plastic sheet and sprayed with a mold release that dried leaving fine Teflon powder... Velostat sheet (0.03 in.) was wrapped around the sample and grounded for improved electrostatic safety. Similar to previous cylinder tests, the...layer of thin Velostat plastic sheet, its contribution to camera viewing distortion of the flame front is not known. Overall, an average velocity over

Exploratory development of foams from liquid crystal polymers

NASA Technical Reports Server (NTRS)

Chung, T. S.

1985-01-01

Two types of liquid crystal polymer (LCP) compositions were studied and evaluated as structural foam materials. One is a copolymer of 6-hydroxy-2-naphthoic acid, terephthalic acid, and p-acetoxyacetanilide (designed HNA/TA/AAA), and the other is a copolymer of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid (designated HBA/HNA). Experimental results showed that the extruded HNA/TA/AA foams have better mechanical quality and appearance than HBA/HNA foams. Heat treatment improved foam tensile strength and break elongation, but reduced their modulus. The injection molding results indicated that nitrogen foaming agents with a low-pressure process gave better void distribution in the injection molded LCP foams than those made by the conventional injection-molding machine and chemical blowing agents. However, in comparing LCP foams with other conventional plastic foams, HBA/HNA foams have better mechanical properties than foamed ABS and PS, but are comparable to PBT and inferior to polycarbonate foams, especially in heat-deflection temperature and impact resistance energy. These deficiencies are due to LCP molecules not having been fully oriented during the Union-Carbide low-pressure foaming process.

Effects of particle size of fiberglass-resin powder from PCBs on the properties and volatile behavior of phenolic molding compound.

PubMed

Guo, Jie; Rao, Qunli; Xu, Zhenming

2010-03-15

Fiberglass-resin powder (FR powder), a mixture of resin powder and glass fibers reclaimed from pulverized waste printed circuit boards (PCBs), is used as a partial substitute of wood flour in the production of modified phenolic molding compound (MPMC). The results show that incorporation of FR powder into MPMC as a filler enhances the thermal stability represented by heat deflection temperature (HDT). MPMC with FR powder smaller than 0.07 mm shows better properties, with a flexural strength of 73 MPa, a charpy notched impact strength of 3.0 kJ/m(2), a HDT of 167 degrees C, and a dielectric strength of 3.7 MV/m, all of which meet the standard data. Thermogravimetric analysis shows that thermal degradation of MPMC mainly includes three steps, and over 55% weight loss of MPMC occurs between temperatures of 370 degrees C and 575 degrees C. Phenol is the main volatile compound released from molding powder during the production of molding product. After molding powder cures to molding product, low level of residual phenol is detected. All the results indicate that the MPMC can be used as a new type of molding compound. (c) 2009 Elsevier B.V. All rights reserved.

Bacillus sp. BS061 Suppresses Gray Mold and Powdery Mildew through the Secretion of Different Bioactive Substances.

PubMed

Kim, Young-Sook; Song, Ja-Gyeong; Lee, In-Kyoung; Yeo, Woon-Hyung; Yun, Bong-Sik

2013-09-01

A Bacillus sp. BS061 significantly reduced disease incidence of gray mold and powdery mildew. To identify the active principle, the culture filtrate was partitioned between butanol and water. The antifungal activity against B. cinerea was evident in the butanol-soluble portion, and active substances were identified as cyclic lipopeptides, iturin A series, by nuclear magnetic resonance spectrometry (NMR) and mass analysis. Interestingly, antifungal activity against powdery mildew was observed in the water-soluble portion, suggesting that cyclic lipopeptides have no responsibility to suppress powdery mildew. This finding reveals that biocontrol agents of Bacillus origin suppress gray mold and powdery mildew through the secretion of different bioactive substances.

Investigations on injection molded, glass-fiber reinforced polyamide 6 integral foams using breathing mold technology

NASA Astrophysics Data System (ADS)

Roch, A.; Kehret, L.; Huber, T.; Henning, F.; Elsner, P.

2015-05-01

Investigations on PA6-GF50 integral foams have been carried out using different material systems: longfiber- and shortfiber-reinforced PA6 as well as unreinforced PA6 as a reference material. Both chemical and physical blowing agents were applied. Breathing mold technology (decompression of the mold) was selected for the foaming process. The integral foam design, which can be conceived as a sandwich structure, helps to save material in the neutral axis area and maintains a distance between load-bearing, unfoamed skin layers. For all test series an initial mold gap of 2.5 mm was chosen and the same amount of material was injected. In order to realize different density reductions, the mold opening stroke was varied. The experiments showed that, at a constant mass per unit area, integral polyamide 6 foams have a significantly higher bending stiffness than compact components, due to their higher area moment of inertia after foaming. At a constant surface weight the bending stiffness in these experiments could be increased by up to 600 %. Both shortfiber- and longfiber-reinforced polyamide 6 showed an increase in energy absorption during foaming.

Fungi in cystic fibrosis and non-cystic fibrosis bronchiectasis.

PubMed

Moss, Richard B

2015-04-01

Bronchiectasis is a pathologic bronchial dilatation with loss of function that can result from multiple inflammatory and infectious injuries to the conducting airways of the lung. Molds, particularly the filamentous fungus Aspergillus fumigatus, have been implicated as a common cause of both cystic fibrosis (CF) and non-CF bronchiectasis, the latter primarily in patients with severe asthma. The pathogenesis of mold-associated bronchiectasis is usually due to atopic sensitization to mold allergens in the presence of active chronic endobronchial fungal infection with host innate and adaptive immune deviation to a Th2-dominated inflammation, a condition known as allergic bronchopulmonary aspergillosis (ABPA) (or allergic bronchopulmonary mycosis if a non-Aspergillus mold is implicated). Diagnostic criteria of ABPA continue to evolve, while treatment relies upon downregulation of the allergic inflammatory response with immunomodulatory agents and antifungal pharmacotherapy. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Farbrication of diffractive optical elements on a Si chip by an imprint lithography using nonsymmetrical silicon mold

NASA Astrophysics Data System (ADS)

Hirai, Yoshihiko; Okano, Masato; Okuno, Takayuki; Toyota, Hiroshi; Yotsuya, Tsutomu; Kikuta, Hisao; Tanaka, Yoshio

2001-11-01

Fabrication of a fine diffractive optical element on a Si chip is demonstrated using imprint lithography. A chirped diffraction grating, which has modulated pitched pattern with curved cross section is fabricated by an electron beam lithography, where the exposure dose profile is automatically optimized by computer aided system. Using the resist pattern as an etching mask, anisotropic dry etching is performed to transfer the resist pattern profile to the Si chip. The etched Si substrate is used as a mold in the imprint lithography. The Si mold is pressed to a thin polymer (poly methyl methacrylate) on a Si chip. After releasing the mold, a fine diffractive optical pattern is successfully transferred to the thin polymer. This method is exceedingly useful for fabrication of integrated diffractive optical elements with electric circuits on a Si chip.

Injection Molding and its application to drug delivery.

PubMed

Zema, Lucia; Loreti, Giulia; Melocchi, Alice; Maroni, Alessandra; Gazzaniga, Andrea

2012-05-10

Injection Molding (IM) consists in the injection, under high pressure conditions, of heat-induced softened materials into a mold cavity where they are shaped. The advantages the technique may offer in the development of drug products concern both production costs (no need for water or other solvents, continuous manufacturing, scalability, patentability) and technological/biopharmaceutical characteristics of the molded items (versatility of the design and composition, possibility of obtaining solid molecular dispersions/solutions of the active ingredient). In this article, process steps and formulation aspects relevant to IM are discussed, with emphasis on the issues and advantages connected with the transfer of this technique from the plastics industry to the production of conventional and controlled-release dosage forms. Moreover, its pharmaceutical applications thus far proposed in the primary literature, intended as either alternative manufacturing strategies for existing products or innovative systems with improved design and performance characteristics, are critically reviewed. Copyright © 2012 Elsevier B.V. All rights reserved.

Observational scores of dampness and mold associated with measurements of microbial agents and moisture in three public schools

PubMed Central

Cho, S. J.; Cox-Ganser, J. M.; Park, J.-H.

2015-01-01

We examined associations between observational dampness scores and measurements of microbial agents and moisture in three public schools. A dampness score was created for each room from 4-point-scale scores (0–3) of water damage, water stains, visible mold, moldy odor, and wetness for each of 8 room components (ceiling, walls, windows, floor, ventilation, furniture, floor trench, and pipes), when present. We created mixed microbial exposure indices (MMEIs) for each of 121 rooms by summing decile ranks of 8 analytes (total culturable fungi; total, Gram-negative, and Gram-positive culturable bacteria; ergosterol; (1→3)-β-D-glucan; muramic acid; and endotoxin) in floor dust. We found significant (P ≤ 0.01) linear associations between the dampness score and culturable bacteria (total, Gram-positive, and Gram-negative) and the MMEIs. Rooms with dampness scores greater than 0.25 (median) had significantly (P < 0.05) higher levels of most microbial agents, MMEIs, and relative moisture content than those with lower scores (≤0.25). Rooms with reported recent water leaks had significantly (P < 0.05) higher dampness scores than those with historical or no reported water leaks. This study suggests that observational assessment of dampness and mold using a standardized form may be valuable for identifying and documenting water damage and associated microbial contamination. PMID:25650175

40 CFR 710.4 - Scope of the inventory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... modifier, pH neutralizer, sequesterant, coagulant, flocculant, fire retardant, lubricant, chelating agent... upon use of curable plastic or rubber molding compounds, inks, drying oils, metal finishing compounds...

Structural modifications of polymethacrylates: impact on thermal behavior and release characteristics of glassy solid solutions.

PubMed

Claeys, Bart; De Coen, Ruben; De Geest, Bruno G; de la Rosa, Victor R; Hoogenboom, Richard; Carleer, Robert; Adriaensens, Peter; Remon, Jean Paul; Vervaet, Chris

2013-11-01

Polymethacrylates such as Eudragit® polymers are well established as drug delivery matrix. Here, we synthesize several Eudragit E PO (n-butyl-, dimethylaminoethyl-, methyl-methacrylate-terpolymer) analogues via free radical polymerization. These polymers are processed via hot melt extrusion, followed by injection molding and evaluated as carriers to produce immediate release solid solution tablets. Three chemical modifications increased the glass transition temperature of the polymer: (a) substitution of n-butyl by t-butyl groups, (b) reduction of the dimethylaminoethyl methacrylate (DMAEMA) content, and (c) incorporation of a bulky isobornyl repeating unit. These structural modifications revealed the possibility to increase the mechanical stability of the tablets via altering the polymer Tg without influencing the drug release characteristics and glassy solid solution forming properties. The presence of DMAEMA units proved to be crucial with respect to API/polymer interaction (essential in creating glassy solid solutions) and drug release characteristics. Moreover, these chemical modifications accentuate the need for a more rational design of (methacrylate) polymer matrix excipients for drug formulation via hot melt extrusion and injection molding. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of road deicing salt on the susceptibility of amphibian embryos to infection by water molds.

PubMed

Karraker, Nancy E; Ruthig, Gregory R

2009-01-01

Some causative agents of amphibian declines act synergistically to impact individual amphibians and their populations. In particular, pathogenic water molds (aquatic oomycetes) interact with environmental stressors and increase mortality in amphibian embryos. We documented colonization of eggs of three amphibian species, the wood frog (Rana sylvatica), the green frog (Rana clamitans), and the spotted salamander (Ambystoma maculatum), by water molds in the field and examined the interactive effects of road deicing salt and water molds, two known sources of mortality for amphibian embryos, on two species, R. clamitans and A. maculatum in the laboratory. We found that exposure to water molds did not affect embryonic survivorship in either A. maculatum or R. clamitans, regardless of the concentration of road salt to which their eggs were exposed. Road salt decreased survivorship of A. maculatum, but not R. clamitans, and frequency of malformations increased significantly in both species at the highest salinity concentration. The lack of an effect of water molds on survival of embryos and no interaction between road salt and water molds indicates that observations of colonization of these eggs by water molds in the field probably represent a secondary invasion of unfertilized eggs or of embryos that had died of other causes. Given increasing salinization of freshwater habitats on several continents and the global distribution of water molds, our results suggest that some amphibian species may not be susceptible to the combined effects of these factors, permitting amphibian decline researchers to devote their attention to other potential causes.

40 CFR 720.30 - Chemicals not subject to notification requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... modifier, pH neutralizer, sequesterant, coagulant, flocculant, fire retardant, lubricant, chelating agent... plastic or rubber molding compounds, inks, drying oils, metal finishing compounds, adhesives, or paints...

Hydrophilic thermoplastic polyurethanes for the manufacturing of highly dosed oral sustained release matrices via hot melt extrusion and injection molding.

PubMed

Verstraete, G; Van Renterghem, J; Van Bockstal, P J; Kasmi, S; De Geest, B G; De Beer, T; Remon, J P; Vervaet, C

2016-06-15

Hydrophilic aliphatic thermoplastic polyurethane (Tecophilic™ grades) matrices for high drug loaded oral sustained release dosage forms were formulated via hot melt extrusion/injection molding (HME/IM). Drugs with different aqueous solubility (diprophylline, theophylline and acetaminophen) were processed and their influence on the release kinetics was investigated. Moreover, the effect of Tecophilic™ grade, HME/IM process temperature, extrusion speed, drug load, injection pressure and post-injection pressure on in vitro release kinetics was evaluated for all model drugs. (1)H NMR spectroscopy indicated that all grades have different soft segment/hard segment ratios, allowing different water uptake capacities and thus different release kinetics. Processing temperature of the different Tecophilic™ grades was successfully predicted by using SEC and rheology. Tecophilic™ grades SP60D60, SP93A100 and TG2000 had a lower processing temperature than other grades and were further evaluated for the production of IM tablets. During HME/IM drug loads up to 70% (w/w) were achieved. In addition, Raman mapping and (M)DSC results confirmed the homogenous distribution of mainly crystalline API in all polymer matrices. Besides, hydrophilic TPU based formulations allowed complete and sustained release kinetics without using release modifiers. As release kinetics were mainly affected by drug load and the length of the PEO soft segment, this polymer platform offers a versatile formulation strategy to adjust the release rate of drugs with different aqueous solubility. Copyright © 2016 Elsevier B.V. All rights reserved.

Pre-release plastic packaging of MEMS and IMEMS devices

DOEpatents

Peterson, Kenneth A.; Conley, William R.

2002-01-01

A method is disclosed for pre-release plastic packaging of MEMS and IMEMS devices. The method can include encapsulating the MEMS device in a transfer molded plastic package. Next, a perforation can be made in the package to provide access to the MEMS elements. The non-ablative material removal process can include wet etching, dry etching, mechanical machining, water jet cutting, and ultrasonic machining, or any combination thereof. Finally, the MEMS elements can be released by using either a wet etching or dry plasma etching process. The MEMS elements can be protected with a parylene protective coating. After releasing the MEMS elements, an anti-stiction coating can be applied. The perforating step can be applied to both sides of the device or package. A cover lid can be attached to the face of the package after releasing any MEMS elements. The cover lid can include a window for providing optical access. The method can be applied to any plastic packaged microelectronic device that requires access to the environment, including chemical, pressure, or temperature-sensitive microsensors; CCD chips, photocells, laser diodes, VCSEL's, and UV-EPROMS. The present method places the high-risk packaging steps ahead of the release of the fragile portions of the device. It also provides protection for the die in shipment between the molding house and the house that will release the MEMS elements and subsequently treat the surfaces.

Spatially Targeted Activation of a Shape Memory, Polymer-Based, Reconfigurable Skin System

DTIC Science & Technology

2014-02-01

bone samples described in ASTM Standard D638 using a CNC router. Compression test samples were cured in an aluminum cylinder mold treated with mold...release with Teflon end plugs and cut to length with a small lathe . 2.2 Tensile/Compressive Tests Tensile tests were conducted on a MTS QTest/1L...fixture with a CNC mill and a decal applied to the front surface for tracking by the DIC system. Figure 10: Shear Test Sample with DIC Decal 10

NK Cells and Their Role in Invasive Mold Infection.

PubMed

Schmidt, Stanislaw; Condorelli, Annalisa; Koltze, Antonia; Lehrnbecher, Thomas

2017-05-19

There is growing evidence that Natural Killer (NK) cells exhibit in vitro activity against both Aspergillus and non- Aspergillus molds. Cytotoxic molecules such as NK cell-derived perforin seem to play an important role in the antifungal activity. In addition, NK cells release a number of cytokines upon stimulation by fungi, which modulate both innate and adaptive host immune responses. Whereas the in vitro data of the antifungal activity of NK cells are supported by animal studies, clinical data are scarce to date.

Epidemiology and treatment approaches in management of invasive fungal infections

PubMed Central

Kriengkauykiat, Jane; Ito, James I; Dadwal, Sanjeet S

2011-01-01

Over the past 20 years, the number of invasive fungal infections has continued to persist, due primarily to the increased numbers of patients subjected to severe immunosuppression. Despite the development of more active, less toxic antifungal agents and the standard use of antifungal prophylaxis, invasive fungal infections (especially invasive mold infections) continue to be a significant factor in hematopoietic cell and solid organ transplantation outcomes, resulting in high mortality rates. Since the use of fluconazole as standard prophylaxis in the hematopoietic cell transplantation setting, invasive candidiasis has come under control, but no mold-active antifungal agent (except for posaconazole in the setting of acute myelogenous leukemia and myelodysplastic syndrome) has been shown to improve the survival rate over fluconazole. With the advent of new azole and echinocandin agents, we have seen the emergence of more azole-resistant and echinocandin-resistant fungi. The recent increase in zygomycosis seen in the hematopoietic cell transplantation setting may be due to the increased use of voriconazole. This has implications for the empiric approach to pulmonary invasive mold infections when zygomycosis cannot be ruled out. It is imperative that an amphotericin B product, an antifungal that has never developed resistance in over 50 years, be initiated. The clinical presentations of invasive mold infections and invasive candidiasis can be nonspecific and the diagnostic tests insensitive, so a high index of suspicion and immediate initiation of empiric therapy is required. Unfortunately, our currently available serologic tests do not predict infection ahead of disease, and, therefore cannot be used to initiate “preemptive” therapy. Also, the Aspergillus galactomannan test gives a false negative result in patients receiving antimold prophylaxis, ie, virtually all of our patients with hematologic malignancy and hematopoietic cell transplant recipients. We may eventually be able to select patients at highest risk for invasive fungal infections for prophylaxis by genetic testing. However, with our current armamentarium of antifungal agents and widespread use of prophylaxis in high-risk groups (hematologic malignancy, hematopoietic cell transplantation), we continue to see high incidence and mortality rates, and our future hope lies in reversing the immunosuppression or augmenting the immune system of these severely immunocompromised hosts by developing and utilizing immunotherapy, immunoprophylaxis, and vaccines. PMID:21750627

[Agents of otomycosis in Manisa region, Turkey, 1995-2011].

PubMed

Değerli, Kenan; Ecemiş, Talat; Günhan, Kıvanç; Başkesen, Tolga; Kal, Elçin

2012-01-01

Otomycosis, which is otitis externa caused by fungi, is common throughout the world especially in tropical and subtropical countries. However, the epidemiologic data about the etiologic agents of otomycosis in Turkey is limited. The aim of this retrospective study was to evaluate the agents of otomycosis in patients living at Manisa region (located at western Anatolia of Turkey). A total of 2279 cases [1465 male, 813 female; age range 1-87 (mean: 41.7) years] who were clinically prediagnosed as otomycosis at Celal Bayar University Hospital, between February 1995 and July 2011, were included in the study. External ear swab samples from patients with suspicion of otomycosis have been evaluated by routine mycological methods. Identification of mold-like fungi was based on colony morphology and microscopic examination of fungal structure, whereas germ tube test, growth characteristics on cornmeal-Tween 80 agar and API 20C AUX (bio-Mérieux, France) system were used for the identification of yeast-like fungi. Of the samples, 28% (638/2279) were found positive by direct microscopy and 24% (544/2279) by culture methods. Among culture-positive cases the isolation rates of mold-like and yeast-like fungi were 66% (359/544) and 34% (185/544), respectively. The number of distribution of the molds were as follows; Aspergillus niger (180), Aspergillus fumigatus (95), Aspergillus terreus (32), Aspergillus flavus (23), Aspergillus spp. (14), Penicillium spp. (13), Trichophyton spp. (T.rubrum 1, T.mentagrophytes 1); while this distribution was as follows for the yeasts; Candida tropicalis (97), Candida albicans (39), Candida parapsilosis (21), Candida glabrata (19), Candida kefyr (4), C.guilliermondii (2), Candida krusei (1), Geotrichum candidum (1) and Trichosporon capitatum (1). It was notable that 96% (344/359) of mold-like fungi were Aspergillus spp., and 99% (183/185) of yeast-like fungi were Candida spp. The results of this study indicated that the most frequent agents of otomycosis were non-dermatophyte species such as Aspergillus, followed by Candida. Dermatophytes were isolated in a small number of otomycosis cases. These data will provide support to the establishment of antifungal therapy guidelines for otomycosis.

A comparative study between melt granulation/compression and hot melt extrusion/injection molding for the manufacturing of oral sustained release thermoplastic polyurethane matrices.

PubMed

Verstraete, G; Mertens, P; Grymonpré, W; Van Bockstal, P J; De Beer, T; Boone, M N; Van Hoorebeke, L; Remon, J P; Vervaet, C

2016-11-20

During this project 3 techniques (twin screw melt granulation/compression (TSMG), hot melt extrusion (HME) and injection molding (IM)) were evaluated for the manufacturing of thermoplastic polyurethane (TPU)-based oral sustained release matrices, containing a high dose of the highly soluble metformin hydrochloride. Whereas formulations with a drug load between 0 and 70% (w/w) could be processed via HME/(IM), the drug content of granules prepared via melt granulation could only be varied between 85 and 90% (w/w) as these formulations contained the proper concentration of binder (i.e. TPU) to obtain a good size distribution of the granules. While release from HME matrices and IM tablets could be sustained over 24h, release from the TPU-based TSMG tablets was too fast (complete release within about 6h) linked to their higher drug load and porosity. By mixing hydrophilic and hydrophobic TPUs the in vitro release kinetics of both formulations could be adjusted: a higher content of hydrophobic TPU was correlated with a slower release rate. Although mini-matrices showed faster release kinetics than IM tablets, this observation was successfully countered by changing the hydrophobic/hydrophilic TPU ratio. In vivo experiments via oral administration to dogs confirmed the versatile potential of the TPU platform as intermediate-strong and low-intermediate sustained characteristics were obtained for the IM tablets and HME mini-matrices, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Isothermal microcalorimetry for antifungal susceptibility testing of Mucorales, Fusarium spp., and Scedosporium spp.

PubMed

Furustrand Tafin, Ulrika; Meis, Jacques F; Trampuz, Andrej

2012-08-01

We evaluated isothermal microcalorimetry for real-time susceptibility testing of non-Aspergillus molds. MIC and minimal effective concentration (MEC) values of Mucorales (n = 4), Fusarium spp. (n = 4), and Scedosporium spp. (n = 4) were determined by microbroth dilution according to the Clinical Laboratory Standard Institute M38-A2 guidelines. Heat production of molds was measured at 37 °C in Sabouraud dextrose broth inoculated with 2.5 × 10(4) spores/mL in the presence of amphotericin B, voriconazole, posaconazole, caspofungin, and anidulafungin. As determined by microcalorimetry, amphotericin B was the most active agent against Mucorales (MHIC 0.06-0.125 μg/mL) and Fusarium spp. (MHIC 1-4 μg/mL), whereas voriconazole was the most active agent against Scedosporium spp. (MHIC 0.25 to 8 μg/mL). The percentage of agreement (within one 2-fold dilution) between the MHIC and MIC (or MEC) was 67%, 92%, 75%, and 83% for amphotericin B, voriconazole, posaconazole, and caspofungin, respectively. Microcalorimetry provides additional information on timing of antifungal activity, enabling further investigation of drug-mold and drug-drug interaction, and optimization of antifungal treatment. Copyright © 2012 Elsevier Inc. All rights reserved.

Hydrophilic absorbable copolyester exhibiting zero-order drug release.

PubMed

Andjelić, Sasa; Yuan, Jenny; Jamiolkowski, Dennis D; Diluccio, Robert; Bezwada, Rao; Zhang, Hua; Mijović, Jovan

2006-04-01

A novel absorbable hydrophilic copolyester developed in our laboratory, amorphous 40/60 poly(ethylene diglycolate-co-glycolide), exhibits outstanding physical properties. Films made from this material appear fully transparent, colorless, soft and slightly elastic, but relatively strong and durable materials so that they can be potentially used as stand-alone devices in various in-vivo medical applications. In this study, in-vitro drug release characteristics of this copolyester were examined. High Performance Liquid Chromatography was used to generate release profiles on selected non-steroidal anti-inflammatory agents, NSAIDs. In addition, dielectric relaxation spectroscopy, as well as mid- and near infrared spectroscopy, were used to study specific polymer chain interactions in water and buffer solution as a function of aging time at 37 degrees C. This copolyester, compression molded into a film, exhibited nearly constant in-vitro release of various hydrophilic and hydrophobic drugs. The release profile showed minimal or, in most cases, no burst effect. The effect was observed with the three NSAIDs that were tested as model compounds; however, this system may prove generally useful for other drug entities. In-vitro hydrolysis conducted at 37 degrees C on this hydrophilic copolyester revealed an unusually long induction period (no hydrolysis for up to 6 days), followed by the relatively rapid hydrolysis. Data from dipole relaxation spectroscopy indicated that the water molecules do not structurally associate with the polymer chains in phosphate buffer during initial hydrolysis period. The results suggest unique dynamics of water diffusion through the polymer matrix that may play a critical role in achieving controlled release properties. Furthermore, we suspect that the molecular interactions associated with this new synthetic absorbable material may find a critical utility in important medical applications.

Preliminary Tests of Gloss-Reduction and Coloring Agents for Camouflage of Polyvinyl Acetate Dust-Control Film

DTIC Science & Technology

1976-02-01

extenders Kaolin powder Calcium carbonate dust Paint flatteners Celite h99 Nytal 1+00 Dry pigments Chalk dust (various colors) Liquid...a dispersant or wetting agent for satisfactory mixing. Vor this purpose, one of two agents was used: (a) a commercial 10 per- cent determent...pockets of unmixed powder, and in some cases the powder settled to the bottom of the mold. The dispersants that were tried did not effectively disperse

Effect of crystals and fibrous network polymer additives on cellular morphology of microcellular foams

NASA Astrophysics Data System (ADS)

Miyamoto, Ryoma; Utano, Tatsumi; Yasuhara, Shunya; Ishihara, Shota; Ohshima, Masahiro

2015-05-01

In this study, the core-back foam injection molding was used for preparing microcelluar polypropylene (PP) foam with either a 1,3:2,4 bis-O-(4-methylbenzylidene)-D-sorbitol gelling agent (Gel-all MD) or a fibros network polymer additive (Metablen 3000). Both agent and addiive could effectively control the celluar morphology in foams but somehow different ways. In course of cooling the polymer with Gel-all MD in the mold caity, the agent enhanced the crystal nucleation and resulted in the large number of small crystals. The crystals acted as effective bubble nucleation agent in foaming process. Thus, the agent reduced the cell size and increased the cell density, drastically. Furthermore, the small crystals provided an inhomogenuity to the expanding cell wall and produced the high open cell content with nano-scale fibril structure. Gell-all as well as Metablene 3000 formed a gel-like fibrous network in melt. The network increased the elongational viscosity and tended to prevent the cell wall from breaking up. The foaming temperature window was widened by the presence of the network. Especially, the temperature window where the macro-fibrous structure was formed was expanded to the higher temperature. The effects of crystal nucleating agent and PTFE on crystals' size and number, viscoelsticity, rheological propreties of PP and cellular morphology were compared and thorougly investigated.

Prevalence of Residential Dampness and Mold Exposure in a University Student Population

PubMed Central

Lanthier-Veilleux, Mathieu; Généreux, Mélissa; Baron, Geneviève

2016-01-01

The impact of residential dampness or mold on respiratory health is well established but few studies have focused on university students. This study aims to: (a) describe the prevalence of exposure to residential dampness or mold in university students according to socio-geographic factors and (b) identify associated housing characteristics. A web survey was conducted in 2014 among the 26,676 students registered at the Université de Sherbrooke (QC, Canada). Residential dampness and mold being closely intertwined, they were considered as a single exposure and assessed using a validated questionnaire. Exposure was compared according to socio-geographic and housing characteristics using chi-square tests and logistic regressions. Among the 2097 participants included in the study (response rate: 8.1%), over 80% were tenants. Residential exposure to dampness or mold was frequent (36.0%, 95% CI: 33.9–38.1). Marked differences for this exposure were noted according to home ownership (39.7% vs. 25.5% among tenants and owners respectively; OR = 1.92%, 95% CI: 1.54–2.38). Campus affiliation, household composition and the number of residents per building were associated with exposure to dampness or mold (p < 0.01), while sex and age were not. Exposure was also associated with older buildings, and buildings in need of renovations and lacking proper ventilation (p < 0.001). This study highlights the potential risk of university students suffering from mold-related health effects given their frequent exposure to this agent. Further research is needed to fully evaluate the mold-related health impact in this at risk group. PMID:26861364

21 CFR 177.1900 - Urea-formaldehyde resins in molded articles.

Code of Federal Regulations, 2011 CFR

2011-04-01

... polymerization-control agent. Tetrachlorophthalic acid anhydride Do. Zinc stearate For use as lubricant. (c) The... and under the conditions of time and temperature characterizing the conditions of its intended use as...

Water-assisted compounding of cellulose nanocrystals into polyamide 6 for use as a nucleating agent for microcellular foaming

Treesearch

Jun Peng; Philip J. Walsh; Ronald C. Sabo; Lih-Sheng Turng; Craig M. Clemons

2016-01-01

Cellulose nanocrystals (CNCs) are a biorenewable filler and can be an excellent nucleating agent for the development of microcellular foamed polymeric nanocomposites. However, their relatively low degradation temperature limits their use with engineering resins like polyamide 6 (PA6) in typical melt processing techniques such as injection molding, compounding, and...

Preliminary evaluation of storax and its constituents: Fungal decay mold and termite resistance

Treesearch

S. Nami Kartal; Evren Terzi; Tsuyoshi Yoshimura; Rachel Arango; Carol A. Clausen; Frederick Green III

2012-01-01

Essential oils and their derivatives might be one of the promising preserving agents to prevent funga ldecay and termite/insect attack in wood since such compounds have a long history of safe usage as antimicrobial agents in various industries. Considerable research has focused on utilizing bioactive essential oils and wood extractives based on green technologies to...

Observational scores of dampness and mold associated with measurements of microbial agents and moisture in three public schools.

PubMed

Cho, S J; Cox-Ganser, J M; Park, J-H

2016-04-01

We examined associations between observational dampness scores and measurements of microbial agents and moisture in three public schools. A dampness score was created for each room from 4-point-scale scores (0-3) of water damage, water stains, visible mold, moldy odor, and wetness for each of 8 room components (ceiling, walls, windows, floor, ventilation, furniture, floor trench, and pipes), when present. We created mixed microbial exposure indices (MMEIs) for each of 121 rooms by summing decile ranks of 8 analytes (total culturable fungi; total, Gram-negative, and Gram-positive culturable bacteria; ergosterol; (1→3)-β-D-glucan; muramic acid; and endotoxin) in floor dust. We found significant (P ≤ 0.01) linear associations between the dampness score and culturable bacteria (total, Gram-positive, and Gram-negative) and the MMEIs. Rooms with dampness scores greater than 0.25 (median) had significantly (P < 0.05) higher levels of most microbial agents, MMEIs, and relative moisture content than those with lower scores (≤0.25). Rooms with reported recent water leaks had significantly (P < 0.05) higher dampness scores than those with historical or no reported water leaks. This study suggests that observational assessment of dampness and mold using a standardized form may be valuable for identifying and documenting water damage and associated microbial contamination. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Breakthrough Invasive Mold Infections in the Hematology Patient: Current Concepts and Future Directions.

PubMed

Lionakis, Michail S; Lewis, Russell E; Kontoyiannis, Dimitrios P

2018-05-31

Although the widespread use of mold-active agents (especially the new-generation of triazoles) has resulted in reductions of documented invasive mold infections (IMIs) in patients with hematological malignancies and allogeneic hematopoietic stem cell transplantation (HSCT), a subset of such patients still develop breakthrough IMIs (bIMIs). There are no data from prospective randomized clinical trials to guide therapeutic decisions in the different scenarios of bIMIs. In this viewpoint, we present the current status of our understanding of the clinical, diagnostic and treatment challenges of bIMIs in high-risk adult patients with hematological cancer and/or HSCT receiving mold-active antifungals and outline common clinical scenarios. As a rule, managing bIMIs demands an individualized treatment plan that takes into account the host, including co-morbidities, certainty of diagnosis and site of bIMIs, local epidemiology, considerations for fungal resistance, and antifungal pharmacological properties. Finally, we highlight areas that require future investigation in this complex area of clinical mycology.

The evaluation of physical properties of injection molded systems based on poly(ethylene oxide) (PEO).

PubMed

Pajander, Jari; Rensonnet, Alexia; Hietala, Sami; Rantanen, Jukka; Baldursdottir, Stefania

2017-02-25

The effect of product design parameters on the formation and properties of an injection molded solid dosage form consisting of poly(ethylene oxide)s (PEO) and two different active pharmaceutical ingredients (APIs) was studied. The product design parameters explored were melting temperature and the duration of melting, API loading degree and the molecular weight (M w ) of PEO. The solid form composition of the model APIs, theophylline and carbamazepine, was of specific interest, and its possible impact on the in vitro drug release behavior. M w of PEO had the greatest impact on the release rate of both APIs. High M w resulted in slower API release rate. Process temperature had two-fold effect with PEO 300,000g/mol. Firstly, higher process temperature transformed the crystalline part of the polymer into metastable folded form (more folded crystalline regions) and less into the more stable extended form (more extended crystalline regions), which lead to enhanced theophylline release rate. Secondly, the higher process temperature seemed to induce carbamazepine polymorphic transformation from p-monoclinic form III (carbamazepine (M)) into trigonal form II (carbamazepine (T)). The results indicated that the actual content of carbamazepine (T) affected drug release behavior more than the magnitude of transformation. Copyright © 2016 Elsevier B.V. All rights reserved.

Abuse-deterrent features of an extended-release morphine drug product developed using a novel injection-molding technology for oral drug delivery.

PubMed

Skak, Nikolaj; Elhauge, Torben; Dayno, Jeffrey M; Lindhardt, Karsten

A novel technology platform (Guardian™ Technology, Egalet Corporation, Wayne, PA) was used to manufacture morphine abuse-deterrent (AD), extended-release (ER), injection-molded tablets (morphine-ADER-IMT; ARYMO® ER [morphine sulfate] ER tablets; Egalet Corporation), a recently approved morphine product with AD labeling. The aim of this article is to highlight how the features of Guardian™ Technology are linked to the ER profile and AD characteristics of morphine-ADER-IMT. The ER profile of morphine-ADER-IMT is attributed to the precise release of morphine from the polymer matrix. The approved dosage strengths of morphine-ADER-IMT are bioequivalent to corresponding dosage strengths of morphine ER (MS Contin®; Purdue Pharma LP, Stamford, CT). Morphine-ADER-IMT was very resistant to physical manipulations intended to reduce particle size, with <10 percent of particles being reduced to <500µm, regarded by the US Food and Drug Administration as a relevant cutoff for potential insufflation in their generic solid oral AD opioid guidance. Furthermore, morphine was not readily extracted from the polymer matrix of morphine-ADER-IMT in small- or large-volume solvent extraction studies that evaluated the potential for intravenous and oral abuse. The ER profile and AD characteristics of morphine-ADER-IMT are a result of Guardian™ Technology. The combination of the polyethylene oxide matrix and the use of injection molding differentiate morphine-ADER-IMT from other approved AD opioids that deter abuse using physical and chemical barriers. The high degree of flexibility of the Guardian™ Technology enables the development of products that can be tailored to almost any desired release profile; as such, it is a technology platform that may be useful for the development of a wide range of pharmaceutical products.

METHOD FOR PRODUCING CEMENTED CARBIDE ARTICLES

DOEpatents

Onstott, E.I.; Cremer, G.D.

1959-07-14

A method is described for making molded materials of intricate shape where the materials consist of mixtures of one or more hard metal carbides or oxides and matrix metals or binder metals thereof. In one embodiment of the invention 90% of finely comminuted tungsten carbide powder together with finely comminuted cobalt bonding agent is incorporated at 60 deg C into a slurry with methyl alcohol containing 1.5% paraffin, 3% camphor, 3.5% naphthalene, and 1.8% toluene. The compact is formed by the steps of placing the slurry in a mold at least one surface of which is porous to the fluid organic system, compacting the slurry, removing a portion of the mold from contact with the formed object and heating the formed object to remove the remaining organic matter and to sinter the compact.

Poly(2-ethyl-2-oxazoline) as matrix excipient for drug formulation by hot melt extrusion and injection molding.

PubMed

Claeys, Bart; Vervaeck, Anouk; Vervaet, Chris; Remon, Jean Paul; Hoogenboom, Richard; De Geest, Bruno G

2012-10-15

Here we evaluate poly(2-ethyl-2-oxazoline)s (PEtOx) as a matrix excipient for the production of oral solid dosage forms by hot melt extrusion (HME) followed by injection molding (IM). Using metoprolol tartrate as a good water-soluble model drug we demonstrate that drug release can be delayed by HME/IM, with the release rate controlled by the molecular weight of the PEtOx. Using fenofibrate as a lipophilic model drug we demonstrate that relative to the pure drug the dissolution rate is strongly enhanced by formulation in HME/IM tablets. For both drug molecules we find that solid solutions, i.e. molecularly dissolved drug in a polymeric matrix, are obtained by HME/IM. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fluxing agent for metal cast joining

DOEpatents

Gunkel, Ronald W.; Podey, Larry L.; Meyer, Thomas N.

2002-11-05

A method of joining an aluminum cast member to an aluminum component. The method includes the steps of coating a surface of an aluminum component with flux comprising cesium fluoride, placing the flux coated component in a mold, filling the mold with molten aluminum alloy, and allowing the molten aluminum alloy to solidify thereby joining a cast member to the aluminum component. The flux preferably includes aluminum fluoride and alumina. A particularly preferred flux includes about 60 wt. % CsF, about 30 wt. % AlF.sub.3, and about 10 wt. % Al.sub.2 O.sub.3.

Photopolymerizable liquid encapsulants for microelectronic devices

NASA Astrophysics Data System (ADS)

Baikerikar, Kiran K.

2000-10-01

Plastic encapsulated microelectronic devices consist of a silicon chip that is physically attached to a leadframe, electrically interconnected to input-output leads, and molded in a plastic that is in direct contact with the chip, leadframe, and interconnects. The plastic is often referred to as the molding compound, and is used to protect the chip from adverse mechanical, thermal, chemical, and electrical environments. Encapsulation of microelectronic devices is typically accomplished using a transfer molding process in which the molding compound is cured by heat. Most transfer molding processes suffer from significant problems arising from the high operating temperatures and pressures required to fill the mold. These aspects of the current process can lead to thermal stresses, incomplete mold filling, and wire sweep. In this research, a new strategy for encapsulating microelectronic devices using photopolymerizable liquid encapsulants (PLEs) has been investigated. The PLEs consist of an epoxy novolac-based vinyl ester resin (˜25 wt.%), fused silica filler (70--74 wt.%), and a photoinitiator, thermal initiator, and silane coupling agent. For these encapsulants, the use of light, rather than heat, to initiate the polymerization allows precise control over when the reaction starts, and therefore completely decouples the mold filling and the cure. The low viscosity of the PLEs allows for low operating pressures and minimizes problems associated with wire sweep. In addition, the in-mold cure time for the PLEs is equivalent to the in-mold cure times of current transfer molding compounds. In this thesis, the thermal and mechanical properties, as well as the viscosity and adhesion of photopolymerizable liquid encapsulants, are reported in order to demonstrate that a UV-curable formulation can have the material properties necessary for microelectronic encapsulation. In addition, the effects of the illumination time, postcure time, fused silica loading, and the inclusion of a thermal initiator on the thermal and mechanical properties of the final cured encapsulants have been investigated. The results show that the material properties of the PLEs are the same, if not better, than those exhibited by conventional transfer molding compounds and demonstrate the potential of using PLEs for encapsulating microelectronic devices.

Laser-assisted photothermal imprinting of nanocomposite

NASA Astrophysics Data System (ADS)

Lu, Y.; Shao, D. B.; Chen, S. C.

2004-08-01

We report on a laser-assisted photothermal imprinting method for directly patterning carbon nanofiber-reinforced polyethylene nanocomposite. A single laser pulse from a solid state Nd :YAG laser (10ns pluse, 532 and 355nm wavelengths) is used to melt/soften a thin skin layer of the polymer nanocomposite. Meanwhile, a fused quartz mold with micro sized surface relief structures is pressed against the surface of the composite. Successful pattern transfer is realized upon releasing the quartz mold. Although polyethylene is transparent to the laser beam, the carbon nanofibers in the high density polyethylene (HDPE) matrix absorb the laser energy and convert it into heat. Numerical heat conduction simulation shows the HDPE matrix is partially melted or softened, allowing for easier imprinting of the relief pattern of the quartz mold.

Comparative Evaluation of Fluoride Releasing Ability of Various Restorative Materials after the Application of Surface Coating Agents – An In-vitro Study

PubMed Central

Kishore, GVS; Sai-Sankar, AJ; Sridhar, M; Pranitha, Kakarla; Sai-Krishna, VS

2016-01-01

Introduction Fluoride plays a key role in prevention of dental caries and is also an essential element for oral health promotion both in children and adults. Aim The aim of the present study was to evaluate the effect of surface coating (petroleum jelly, G-Coat Plus) on the fluoride releasing property of conventional Glass Ionomer Cement (GIC) and Zirconomer. Materials and Methods A total of 30 disk shaped brass mold specimens (6±0.1mm in diameter and 2±0.1mm thickness) for each test group were fabricated with conventional GIC (Group A) and Zirconomer (Group B). These test groups were further divided into three subgroups of 10 each. The unprotected specimens act as control (Group A1 and B1), G-Coat Plus specimens as (Group A2 and B2) and for the remaining specimens petroleum jelly was applied (Group A3 and B3). Fluoride ion concentration was measured with a combination of fluoride ion specific electrode and ion analyzer for every 24 hours for 15 days. The data was statistically analyzed using Kruskal Wallis and Mann-Whitney U test. Results The Group B released significantly more fluoride than Group A. Among all the subgroups the greatest amount of fluoride was released from Group B1, in the first 24 hours followed by A1 and B2. The least was observed on 15th day with Group B3 and A3. Conclusion Both the tested materials (GIC and Zirconomer) used in the study exhibited fluoride release whether protected or unprotected with surface coating. Though there was a difference between the groups, the pattern of fluoride release was similar and continuous throughout the study period i.e., first the initial burst followed by sustained release. The results revealed Zirconomer released more fluoride and is comparable to conventional GIC. PMID:28209001

Comparative Evaluation of Fluoride Releasing Ability of Various Restorative Materials after the Application of Surface Coating Agents - An In-vitro Study.

PubMed

Kishore, Gvs; Sai-Sankar, A J; Pratap-Gowd, Mjs; Sridhar, M; Pranitha, Kakarla; Sai-Krishna, V S

2016-12-01

Fluoride plays a key role in prevention of dental caries and is also an essential element for oral health promotion both in children and adults. The aim of the present study was to evaluate the effect of surface coating (petroleum jelly, G-Coat Plus) on the fluoride releasing property of conventional Glass Ionomer Cement (GIC) and Zirconomer. A total of 30 disk shaped brass mold specimens (6±0.1mm in diameter and 2±0.1mm thickness) for each test group were fabricated with conventional GIC (Group A) and Zirconomer (Group B). These test groups were further divided into three subgroups of 10 each. The unprotected specimens act as control (Group A1 and B1), G-Coat Plus specimens as (Group A2 and B2) and for the remaining specimens petroleum jelly was applied (Group A3 and B3). Fluoride ion concentration was measured with a combination of fluoride ion specific electrode and ion analyzer for every 24 hours for 15 days. The data was statistically analyzed using Kruskal Wallis and Mann-Whitney U test. The Group B released significantly more fluoride than Group A. Among all the subgroups the greatest amount of fluoride was released from Group B1, in the first 24 hours followed by A1 and B2. The least was observed on 15 th day with Group B3 and A3. Both the tested materials (GIC and Zirconomer) used in the study exhibited fluoride release whether protected or unprotected with surface coating. Though there was a difference between the groups, the pattern of fluoride release was similar and continuous throughout the study period i.e., first the initial burst followed by sustained release. The results revealed Zirconomer released more fluoride and is comparable to conventional GIC.

21 CFR 177.1460 - Melamine-formaldehyde resins in molded articles.

Code of Federal Regulations, 2012 CFR

2012-04-01

... polymerization reaction control agent. Phthalic acid anhydride Do. Zinc stearate For use as lubricant. (c) The... extracted with the solvent or solvents characterizing the type of food and under the conditions of time and...

Preparation of Permanent Mold Coating Using Magnesia Powder for Magnesium Alloys

NASA Astrophysics Data System (ADS)

Guo, Guangsi; Wang, Guangtai; Yu, Haifeng; Ye, Sheng

A kind of permanent mold coating for magnesium alloy was developed using magnesia powder and diatomite as refractory aggregate. The properties of the coating were tested and analyzed by various ingredients. The final ingredient was determined through the tests which are to find out the optimal proportion of two kinds of aggregate and the influences to coating properties by changing the proportion of binder and suspending agents. The experimental results shown that the permanent mold coating performed good properties on magnesium alloys when the optimized ratio of magnesia powder and diatomite was 6: 4, and the integrated property is very excellent when the coating was prepared with 2 percent of sodium bentonite, 0.4 percent of CMC, 7 percent of sodium hexametaphosphate, and 7 percent of sodium silicate. The excellent performance has also been proved by actual casting test.

Impact of a native Streptomyces flavovirens from mushroom compost on green mold control and yield of Agaricus bisporus.

PubMed

Šantrić, Ljiljana; Potočnik, Ivana; Radivojević, Ljiljana; Umiljendić, Jelena Gajić; Rekanović, Emil; Duduk, Bojan; Milijašević-Marčić, Svetlana

2018-05-18

Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) substrates (i.e., compost in different phases of composting, black peat or casing layer) in Serbia in 2014-2016 were tested in vitro against the causal agents of green mold in cultivated mushroom. Out of six most promising isolates, A06 induced 42.4% in vitro growth inhibition of Trichoderma harzianum T54, and 27.6% inhibition of T. aggressivum f. europaeum T77. The novel strain A06 was identified as Streptomyces flavovirens based on macroscopic and cultural characteristics and 16S rDNA sequence and used in mushroom growing room experiments. Actinobacteria had no negative influence on mycelial growth of the cultivated mushroom in compost in situ. Isolate S. flavovirens A06 enhanced mushroom yield significantly, up to 31.5%. The A06 isolate was more efficient in enhancing yield after inoculation with the compost mold T. aggressivum (26.1%), compared to casing mold T. harzianum (8%). Considering disease incidence, actinobacteria significantly prevented green mold in compost caused by T. aggressivum (6.8%). However, fungicide prochloraz-Mn had a more significant role in reducing symptoms of casing mold, T. harzianum, in comparison with actinobacteria (24.2 and 11.8%, respectively). No significant differences between efficacies of S. flavovirens A06 and the fungicide prochloraz-Mn against T. aggressivum were revealed. These results imply that S. flavovirens A06 can be used to increase mushroom yield and contribute to disease control against the aggressive compost green mold disease caused by Trichoderma aggressivum.

Fungal Fragments as Indoor Air Biocontaminants

PubMed Central

Górny, Rafał L.; Reponen, Tiina; Willeke, Klaus; Schmechel, Detlef; Robine, Enric; Boissier, Marjorie; Grinshpun, Sergey A.

2002-01-01

The aerosolization process of fungal propagules of three species (Aspergillus versicolor, Penicillium melinii, and Cladosporium cladosporioides) was studied by using a newly designed and constructed aerosolization chamber. We discovered that fungal fragments are aerosolized simultaneously with spores from contaminated agar and ceiling tile surfaces. Concentration measurements with an optical particle counter showed that the fragments are released in higher numbers (up to 320 times) than the spores. The release of fungal propagules varied depending on the fungal species, the air velocity above the contaminated surface, and the texture and vibration of the contaminated material. In contrast to spores, the release of fragments from smooth surfaces was not affected by air velocity, indicating a different release mechanism. Correlation analysis showed that the number of released fragments cannot be predicted on the basis of the number of spores. Enzyme-linked immunosorbent assays with monoclonal antibodies produced against Aspergillus and Penicillium fungal species showed that fragments and spores share common antigens, which not only confirmed the fungal origin of the fragments but also established their potential biological relevance. The considerable immunological reactivity, the high number, and the small particle size of the fungal fragments may contribute to human health effects that have been detected in buildings with mold problems but had no scientific explanation until now. This study suggests that future fungal spore investigations in buildings with mold problems should include the quantitation of fungal fragments. PMID:12089037

Gelcasting polymeric precursors for producing net-shaped graphites

DOEpatents

Klett, James W.; Janney, Mark A.

2002-01-01

The present invention discloses a method for molding complex and intricately shaped high density monolithic carbon, carbon-carbon, graphite, and thermoplastic composites using gelcasting technology. The method comprising a polymeric carbon precursor, a solvent, a dispersant, an anti-foaming agent, a monomer system, and an initiator system. The components are combined to form a suspension which is poured into a mold and heat-treated to form a thermoplastic part. The thermoplastic part can then be further densified and heat-treated to produce a high density carbon or graphite composite. The present invention also discloses the products derived from this method.

Chemistry and toxicology of molds isolated from water-damaged buildings.

PubMed

Jarvis, Bruce B

2002-01-01

There is increasing evidence of health risks associated with damp buildings and homes in which high levels of microbes are found. Although concerns have traditionally centered on microbial pathogens and allergenic effects, recent work has suggested that fungi pose the more serious risk. Evidence is accumulating that certain toxigenic molds are particularly a risk for human health through exposure, via inhalation, of fungal spores. Many of these fungi produce toxins (mycotoxins) some of which have been shown to cause animal and human intoxications, usually in an agricultural setting. The fungus, Stachybotrys chartarum (S. atra) is considered to be one of the more serious threats to people living and working in water-damaged buildings. This mold has a long history of being responsible for animal toxicoses, and in recent years, being associated with infant pulmonary hemosiderosis (bleeding in the lungs) of infants exposed to spores of this fungus in their homes. S. atra produces a variety of potent toxins and immunosuppressant agents, including a novel class of diterpenes (atranones) of unusual structure. More research is needed to determine the impact to health resulting from inhalation of toxigenic mold spores.

Nonaqueous slip casting of high temperature ceramic superconductors using an investment casting technique

NASA Technical Reports Server (NTRS)

Hooker, Matthew W. (Inventor); Taylor, Theodore D. (Inventor); Wise, Stephanie A. (Inventor); Buckley, John D. (Inventor); Vasquez, Peter (Inventor); Buck, Gregory M. (Inventor); Hicks, Lana P. (Inventor)

1993-01-01

A process for slip casting ceramic articles that does not employ parting agents and affords the casting of complete, detailed, precision articles that do not possess parting lines is presented. This process is especially useful for high temperature superconductors and water-sensitive ceramics. A wax pattern for a shell mold is provided, and an aqueous mixture of a calcium sulfate-bonded investment material is applied as a coating to the wax pattern. The coated wax pattern is then dried, followed by curing to vaporize the wax pattern and leave a shell mold of the calcium sulfate-bonded investment material. The shell mold is cooled to room temperature, and a ceramic slip, created by dispersing a ceramic powder in an organic liquid, is poured therein. After a ceramic shell of desired thickness or a solid article has set up in the shell mold, excess ceramic slip is poured out. The shell mold is misted with water and peeled away from the ceramic article, after which the ceramic is fired to provide a complete, detailed, precision, high temperature superconductive ceramic article without parting lines. The casting technique may take place in the presence of a magnetic field to orient the ceramic powders during the casting process.

49 CFR 40.331 - To what additional parties must employers and service agents release information?

Code of Federal Regulations, 2010 CFR

2010-10-01

... service agents release information? 40.331 Section 40.331 Transportation Office of the Secretary of... Release of Information § 40.331 To what additional parties must employers and service agents release information? As an employer or service agent you must release information under the following circumstances...

40 CFR 761.62 - Disposal of PCB bulk product waste.

Code of Federal Regulations, 2012 CFR

2012-07-01

... molded rubber parts and components; applied dried paints, varnishes, waxes or other similar coatings or... released or dispersed by wind or other action; or (2) Under asphalt as part of a road bed. [63 FR 35451...

40 CFR 761.62 - Disposal of PCB bulk product waste.

Code of Federal Regulations, 2014 CFR

2014-07-01

... molded rubber parts and components; applied dried paints, varnishes, waxes or other similar coatings or... released or dispersed by wind or other action; or (2) Under asphalt as part of a road bed. [63 FR 35451...

40 CFR 761.62 - Disposal of PCB bulk product waste.

Code of Federal Regulations, 2013 CFR

2013-07-01

... molded rubber parts and components; applied dried paints, varnishes, waxes or other similar coatings or... released or dispersed by wind or other action; or (2) Under asphalt as part of a road bed. [63 FR 35451...

40 CFR 761.62 - Disposal of PCB bulk product waste.

Code of Federal Regulations, 2011 CFR

2011-07-01

... molded rubber parts and components; applied dried paints, varnishes, waxes or other similar coatings or... released or dispersed by wind or other action; or (2) Under asphalt as part of a road bed. [63 FR 35451...

Anti-Toxoplasma activity and impact evaluation of lyophilization, hot molding process, and gamma-irradiation techniques on CLH-PLGA intravitreal implants.

PubMed

Fernandes-Cunha, Gabriella M; Rezende, Cíntia M F; Mussel, Wagner N; da Silva, Gisele R; de L Gomes, Elionai C; Yoshida, Maria I; Fialho, Sílvia L; Goes, Alfredo M; Gomes, Dawison A; de Almeida Vitor, Ricardo W; Silva-Cunha, Armando

2016-01-01

Intraocular delivery systems have been developed to treat many eye diseases, especially those affecting the posterior segment of the eye. However, ocular toxoplasmosis, the leading cause of infectious posterior uveitis in the world, still lacks an effective treatment. Therefore, our group developed an intravitreal polymeric implant to release clindamycin, a potent anti-Toxoplasma antibiotic. In this work, we used different techniques such as differential scanning calorimetry, thermogravimetry, X-ray diffraction, scanning electron microscopy, and fourier-transform infrared spectroscopy to investigate drug/polymer properties while manufacturing the delivery system. We showed that the lyophilization, hot molding process, and sterilization by gamma irradiation did not change drug/polymer physical-chemistry properties. The drug was found to be homogeneously dispersed into the poly lactic-co-glycolic acid (PLGA) chains and the profile release was characterized by an initial burst followed by prolonged release. The drug profile release was not modified after gamma irradiation and non-covalent interaction was found between the drug and the PLGA. We also observed the preservation of the drug activity by showing the potent anti-Toxoplasma effect of the implant, after 24-72 h in contact with cells infected by the parasite, which highlights this system as an alternative to treat toxoplasmic retinochoroiditis.

Preparation and investigation of novel gastro-floating tablets with 3D extrusion-based printing.

PubMed

Li, Qijun; Guan, Xiaoying; Cui, Mengsuo; Zhu, Zhihong; Chen, Kai; Wen, Haoyang; Jia, Danyang; Hou, Jian; Xu, Wenting; Yang, Xinggang; Pan, Weisan

2018-01-15

Three dimensional (3D) extrusion-based printing is a paste-based rapid prototyping process, which is capable of building complex 3D structures. The aim of this study was to explore the feasibility of 3D extrusion-based printing as a pharmaceutical manufacture technique for the fabrication of gastro-floating tablets. Novel low-density lattice internal structure gastro-floating tablets of dipyridamole were developed to prolong the gastric residence time in order to improve drug release rate and consequently, improve bioavailability and therapeutic efficacy. Excipients commonly employed in the pharmaceutical study could be efficiently applied in the room temperature 3D extrusion-based printing process. The tablets were designed with three kinds of infill percentage and prepared by hydroxypropyl methylcellulose (HPMC K4M) and hydroxypropyl methylcellulose (HPMC E15) as hydrophilic matrices and microcrystalline cellulose (MCC PH101) as extrusion molding agent. In vitro evaluation of the 3D printed gastro-floating tablets was performed by determining mechanical properties, content uniformity, and weight variation. Furthermore, re-floating ability, floating duration time, and drug release behavior were also evaluated. Dissolution profiles revealed the relationship between infill percentage and drug release behavior. The results of this study revealed the potential of 3D extrusion-based printing to fabricate gastro-floating tablets with more than 8h floating process with traditional pharmaceutical excipients and lattice internal structure design. Copyright © 2017. Published by Elsevier B.V.

A review of the mechanism of injury and treatment approaches for illness resulting from exposure to water-damaged buildings, mold, and mycotoxins.

PubMed

Hope, Janette

2013-01-01

Physicians are increasingly being asked to diagnose and treat people made ill by exposure to water-damaged environments, mold, and mycotoxins. In addition to avoidance of further exposure to these environments and to items contaminated by these environments, a number of approaches have been used to help persons affected by exposure to restore their health. Illness results from a combination of factors present in water-damaged indoor environments including, mold spores and hyphal fragments, mycotoxins, bacteria, bacterial endotoxins, and cell wall components as well as other factors. Mechanisms of illness include inflammation, oxidative stress, toxicity, infection, allergy, and irritant effects of exposure. This paper reviews the scientific literature as it relates to commonly used treatments such as glutathione, antioxidants, antifungals, and sequestering agents such as cholestyramine, charcoal, clay and chlorella, antioxidants, probiotics, and induced sweating.

A Review of the Mechanism of Injury and Treatment Approaches for Illness Resulting from Exposure to Water-Damaged Buildings, Mold, and Mycotoxins

PubMed Central

2013-01-01

Physicians are increasingly being asked to diagnose and treat people made ill by exposure to water-damaged environments, mold, and mycotoxins. In addition to avoidance of further exposure to these environments and to items contaminated by these environments, a number of approaches have been used to help persons affected by exposure to restore their health. Illness results from a combination of factors present in water-damaged indoor environments including, mold spores and hyphal fragments, mycotoxins, bacteria, bacterial endotoxins, and cell wall components as well as other factors. Mechanisms of illness include inflammation, oxidative stress, toxicity, infection, allergy, and irritant effects of exposure. This paper reviews the scientific literature as it relates to commonly used treatments such as glutathione, antioxidants, antifungals, and sequestering agents such as Cholestyramine, charcoal, clay and chlorella, antioxidants, probiotics, and induced sweating. PMID:23710148

ELISA measurement of stachylysin in serum to quantify human exposures to the indoor mold Stachybotrys chartarum.

PubMed

Van Emon, Jeanette M; Reed, Allan W; Yike, Iwona; Vesper, Stephen J

2003-06-01

The goal of this research was to develop a measurable indicator of human exposure to Stachyborys chartarum. Antibodies were produced against the hemolytic agent stachylysin obtained from the mold S. chartarum. These antibodies were used to develop two enzyme-linked immunosorbent assay methods for the analysis of stachylysin in human and rat sera and environmental samples. Stachylysin was measured in rat pups that received nasal instillations of S. chartarum conidia but not in control rat serum. Stachylysin in the serum of five human adults exposed to S. chartarum in water-damaged environments was 371 ng/mL but none was detected in the control serum. Stachylysin was also quantified in spore, wallboard, mycelial, and dust samples. The measurement of stachylysin may be a useful indicator in assessing human exposure to S. chartarum and in determining the presence of this indoor mold.

Preparing silica aerogel monoliths via a rapid supercritical extraction method.

PubMed

Carroll, Mary K; Anderson, Ann M; Gorka, Caroline A

2014-02-28

A procedure for the fabrication of monolithic silica aerogels in eight hours or less via a rapid supercritical extraction process is described. The procedure requires 15-20 min of preparation time, during which a liquid precursor mixture is prepared and poured into wells of a metal mold that is placed between the platens of a hydraulic hot press, followed by several hours of processing within the hot press. The precursor solution consists of a 1.0:12.0:3.6:3.5 x 10(-3) molar ratio of tetramethylorthosilicate (TMOS):methanol:water:ammonia. In each well of the mold, a porous silica sol-gel matrix forms. As the temperature of the mold and its contents is increased, the pressure within the mold rises. After the temperature/pressure conditions surpass the supercritical point for the solvent within the pores of the matrix (in this case, a methanol/water mixture), the supercritical fluid is released, and monolithic aerogel remains within the wells of the mold. With the mold used in this procedure, cylindrical monoliths of 2.2 cm diameter and 1.9 cm height are produced. Aerogels formed by this rapid method have comparable properties (low bulk and skeletal density, high surface area, mesoporous morphology) to those prepared by other methods that involve either additional reaction steps or solvent extractions (lengthier processes that generate more chemical waste).The rapid supercritical extraction method can also be applied to the fabrication of aerogels based on other precursor recipes.

Preparing Silica Aerogel Monoliths via a Rapid Supercritical Extraction Method

PubMed Central

Gorka, Caroline A.

2014-01-01

A procedure for the fabrication of monolithic silica aerogels in eight hours or less via a rapid supercritical extraction process is described. The procedure requires 15-20 min of preparation time, during which a liquid precursor mixture is prepared and poured into wells of a metal mold that is placed between the platens of a hydraulic hot press, followed by several hours of processing within the hot press. The precursor solution consists of a 1.0:12.0:3.6:3.5 x 10-3 molar ratio of tetramethylorthosilicate (TMOS):methanol:water:ammonia. In each well of the mold, a porous silica sol-gel matrix forms. As the temperature of the mold and its contents is increased, the pressure within the mold rises. After the temperature/pressure conditions surpass the supercritical point for the solvent within the pores of the matrix (in this case, a methanol/water mixture), the supercritical fluid is released, and monolithic aerogel remains within the wells of the mold. With the mold used in this procedure, cylindrical monoliths of 2.2 cm diameter and 1.9 cm height are produced. Aerogels formed by this rapid method have comparable properties (low bulk and skeletal density, high surface area, mesoporous morphology) to those prepared by other methods that involve either additional reaction steps or solvent extractions (lengthier processes that generate more chemical waste).The rapid supercritical extraction method can also be applied to the fabrication of aerogels based on other precursor recipes. PMID:24637334

Bio Warfare and Terrorism: Toxins and Other Mid-Spectrum Agents

DTIC Science & Technology

2005-01-01

biotechnology, toxicogenomics, toxin, tetrodotoxin, and others. Once an agent has and proteomics may also help to open the door to the 276 Bio Warfare...also interferon gamma, interleukin-6, and tumor alsointrfern gmma intrlekin6, ad tmor by the mold Aspergillus flavus and commonly conta- necrosis factor...as bullets. No the new sciences of genomics and proteomics to alter toxoid or antitoxin is available, genetic code and to affect the expression of

21 CFR 181.28 - Release agents.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Release agents. Substances classified as release agents, when migrating from food-packaging material shall... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Release agents. 181.28 Section 181.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 181.28 - Release agents.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Release agents. 181.28 Section 181.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Release agents. Substances classified as release agents, when migrating from food-packaging material shall...

21 CFR 181.28 - Release agents.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Release agents. Substances classified as release agents, when migrating from food-packaging material shall... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Release agents. 181.28 Section 181.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 181.28 - Release agents.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Release agents. Substances classified as release agents, when migrating from food-packaging material shall... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Release agents. 181.28 Section 181.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

Microstructure and properties of FeSiCr/PA6 composites by injection molding using FeSiCr powders by phosphating and coupling treatment

NASA Astrophysics Data System (ADS)

Wang, Lulu; Qiao, Liang; Zheng, Jingwu; Cai, Wei; Ying, Yao; Li, Wangchang; Che, Shenglei; Yu, Jing

2018-04-01

FeSiCr/PA6 composites were prepared by injection molding using the FeSiCr powders modified by different phosphating agents and KH550 coupling agent. The resistivity, impact strength, magnetic permeability and magnetic loss of the FeSiCr/PA6 composites were measured. The morphologies of different FeSiCr powders and the FeSiCr/PA6 composites were also observed by scanning electron microscope (SEM). The results showed that 1-Hydroxyethylidene-1,1-diphosphonic acid, phytic acid and H3PO4 could improve the electrical resistivity of FeSiCr powders by forming the dense phosphating layer except diphenylphosphinic acid. However, the resistivity of FeSiCr/PA6 composites using the FeSiCr powders treated by all the four phosphating agents had no obvious increase though the phosphating layer on the surface of FeSiCr powder came into being. The nylon insulation layer had much stronger influence than the phosphating layer on electrical resistivity of the composites. After adding appropriate KH550 coupling agent, the impact strengths of FeSiCr/PA6 composites were significantly improved, which may be associated with the tiny gap between FeSiCr powder and PA6 matrix. The effects of the phosphating agents on the magnetic permeability and loss of the FeSiCr/PA6 were small and the mechanism were also discussed.

21 CFR 178.3860 - Release agents.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Release agents. 178.3860 Section 178.3860 Food and... and Production Aids § 178.3860 Release agents. Substances listed in paragraph (b) of this section may be safely used as release agents in petroleum wax complying with § 178.3710 and in polymeric resins...

Susceptibility Testing of Common and Uncommon Aspergillus Species against Posaconazole and Other Mold-Active Antifungal Azoles Using the Sensititre Method.

PubMed

Mello, Enrica; Posteraro, Brunella; Vella, Antonietta; De Carolis, Elena; Torelli, Riccardo; D'Inzeo, Tiziana; Verweij, Paul E; Sanguinetti, Maurizio

2017-06-01

We tested 59 common and 27 uncommon Aspergillus species isolates for susceptibility to the mold-active azole antifungal agents itraconazole, voriconazole, and posaconazole using the Sensititre method. The overall essential agreement with the CLSI reference method was 96.5% for itraconazole and posaconazole and was 100% for voriconazole. By the Sensititre method as well as the CLSI reference method, all of 10 A. fumigatus isolates with a cyp51 mutant genotype were classified as being non-wild-type isolates (MIC > epidemiological cutoff value [ECV]) with respect to triazole susceptibility. Copyright © 2017 American Society for Microbiology.

Susceptibility Testing of Common and Uncommon Aspergillus Species against Posaconazole and Other Mold-Active Antifungal Azoles Using the Sensititre Method

PubMed Central

Mello, Enrica; Posteraro, Brunella; Vella, Antonietta; De Carolis, Elena; Torelli, Riccardo; D'Inzeo, Tiziana; Verweij, Paul E.

2017-01-01

ABSTRACT We tested 59 common and 27 uncommon Aspergillus species isolates for susceptibility to the mold-active azole antifungal agents itraconazole, voriconazole, and posaconazole using the Sensititre method. The overall essential agreement with the CLSI reference method was 96.5% for itraconazole and posaconazole and was 100% for voriconazole. By the Sensititre method as well as the CLSI reference method, all of 10 A. fumigatus isolates with a cyp51 mutant genotype were classified as being non-wild-type isolates (MIC > epidemiological cutoff value [ECV]) with respect to triazole susceptibility. PMID:28416538

Influence of temperature and relative humidity conditions on the pan coating of hydroxypropyl cellulose molded capsules.

PubMed

Macchi, Elena; Zema, Lucia; Pandey, Preetanshu; Gazzaniga, Andrea; Felton, Linda A

2016-03-01

In a previous study, hydroxypropyl cellulose (HPC)-based capsular shells prepared by injection molding and intended for pulsatile release were successfully coated with 10mg/cm(2) Eudragit® L film. The suitability of HPC capsules for the development of a colon delivery platform based on a time dependent approach was demonstrated. In the present work, data logging devices (PyroButton®) were used to monitor the microenvironmental conditions, i.e. temperature (T) and relative humidity (RH), during coating processes performed under different spray rates (1.2, 2.5 and 5.5g/min). As HPC-based capsules present special features, a preliminary study was conducted on commercially available gelatin capsules for comparison purposes. By means of PyroButton data-loggers it was possible to acquire information about the impact of the effective T and RH conditions experienced by HPC substrates during the process on the technological properties and release performance of the coated systems. The use of increasing spray rates seemed to promote a tendency of the HPC shells to slightly swell at the beginning of the spraying process; moreover, capsules coated under spray rates of 1.2 and 2.5g/min showed the desired release performance, i.e. ability to withstand the acidic media followed by the pulsatile release expected for uncoated capsules. Preliminary stability studies seemed to show that coating conditions might also influence the release performance of the system upon storage. Copyright © 2015 Elsevier B.V. All rights reserved.

Characteristics and antimicrobial activity of copper-based materials

NASA Astrophysics Data System (ADS)

Li, Bowen

In this study, copper vermiculite was synthesized, and the characteristics, antimicrobial effects, and chemical stability of copper vermiculite were investigated. Two types of copper vermiculite materials, micron-sized copper vermiculite (MCV) and exfoliated copper vermiculite (MECV), are selected for this research. Since most of the functional fillers used in industry products, such as plastics, paints, rubbers, papers, and textiles prefer micron-scaled particles, micron-sized copper vermiculite was prepared by jet-milling vermiculite. Meanwhile, since the exfoliated vermiculite has very unique properties, such as high porosity, specific surface area, high aspect ratio of laminates, and low density, and has been extensively utilized as a functional additives, exfoliated copper vermiculite also was synthesized and investigated. The antibacterial efficiency of copper vermiculite was qualitatively evaluated by the diffusion methods (both liquid diffusion and solid diffusion) against the most common pathogenic species: Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Klebsiella pneumoniae (K. pneumoniae). The result showed that the release velocity of copper from copper vermiculite is very slow. However, copper vermiculite clearly has excellent antibacterial efficiency to S. aureus, K. pneumoniae and E. coli. The strongest antibacterial ability of copper vermiculite is its action on S. aureus. The antibacterial efficiency of copper vermiculite was also quantitatively evaluated by determining the reduction rate (death rate) of E. coli versus various levels of copper vermiculite. 10 ppm of copper vermiculite in solution is sufficient to reduce the cell population of E. coli, while the untreated vermiculite had no antibacterial activity. The slow release of copper revealed that the antimicrobial effect of copper vermiculite was due to the strong interactions between copper ions and bacteria cells. Exfoliated copper vermiculite has even stronger antibacterial activity than copper vermiculite against E. coli. With 200 ppm exfoliated copper vermiculite in bacteria suspension (4.68 ppm of metal copper), the reduction of viable bacteria are 99.8% at 1 hour, and >99.9% at 2 hours. With 10 ppm exfoliated copper vermiculite in bacteria dilution (0.234 ppm of copper atoms), the reduction of viable E. coli reached 98.7% at 1 hour, and >95.6% at 2 hours. Molds have the potential to cause health problems, such as allergic reactions, irritations, and mycotoxins, and damage to buildings, historic relics, properties, etc. Since copper has better antifungal property, an initial antifungal activity of copper vermiculite was evaluated in this study. Fat-free milk was used to develop molds in the test samples by saturated samples. Incubated at 36°C for 48 hours, all of the surfaces of untreated control samples, including micron-sized vermiculite, exfoliated vermiculite, bentonite, and kaolin, have been covered by thick mold layers. However, there were no mold showed on copper vermiculite and exfoliated copper vermiculite. Even after the incubation was lasted for 10 days, copper vermiculite and exfoliated copper vermiculite did not show any mold on the surface. These results exhibited copper vermiculite has excellent antifungal activities against mold. Stability of copper ions in copper vermiculite was measured by aqueous leaching process. Copper vermiculite and exfoliated copper vermiculite were put into distilled water in a ratio of 2.0g/100ml, and then implemented leaching processes by continuously shaking (leaching) and statically storing (soaking) for desired periods of time, respectively. According to the analytic result by inductively coupled plasma spectroscopy (ICP), the major metals released were copper, magnesium, iron, silicon, and aluminum. The release rate of copper depends on the environmental conditions. Under the dynamic leaching condition, all the major elements had shown linear leaching rates, and slowly increases along with the leaching time. Copper concentration in 1 hour leached solutions had sufficient concentration to inhibit E. coli in aqueous solution. Lasting for 1 month, 1 gram of copper vermiculite only released 185mug of copper. At this velocity, 11.5 years are required to completely exhaust the copper atoms from copper vermiculite. A soaking process provided a lower release rate than leaching process. Comparably, exfoliated copper vermiculite had lower copper concentration, stronger antimicrobial effect, but faster release rate than copper vermiculite, due to their different structure characteristics. (Abstract shortened by UMI.)

42 CFR 73.11 - Security.

Code of Federal Regulations, 2010 CFR

2010-10-01

... select agent or toxin against unauthorized access, theft, loss, or release. (b) The security plan must be... activities, loss or theft of select agents or toxins, release of select agents or toxins, or alteration of... of select agents or toxins, (iv) Any release of a select agent or toxin, and (v) Any sign that...

9 CFR 121.11 - Security.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the select agent or toxin against unauthorized access, theft, loss, or release. (b) The security plan... activities, loss or theft of select agents or toxins, release of select agents or toxins, or alteration of... of select agents or toxins; (iv) Any release of a select agent or toxin; and (v) Any sign that...

Comparison of Infectious Agents Susceptibility to Photocatalytic Effects of Nanosized Titanium and Zinc Oxides: A Practical Approach

NASA Astrophysics Data System (ADS)

Bogdan, Janusz; Zarzyńska, Joanna; Pławińska-Czarnak, Joanna

2015-08-01

Nanotechnology contributes towards a more effective eradication of pathogens that have emerged in hospitals, veterinary clinics, and food processing plants and that are resistant to traditional drugs or disinfectants. Since new methods of pathogens eradication must be invented and implemented, nanotechnology seems to have become the response to that acute need. A remarkable achievement in this field of science was the creation of self-disinfecting surfaces that base on advanced oxidation processes (AOPs). Thus, the phenomenon of photocatalysis was practically applied. Among the AOPs that have been most studied in respect of their ability to eradicate viruses, prions, bacteria, yeasts, and molds, there are the processes of TiO2/UV and ZnO/UV. Titanium dioxide (TiO2) and zinc oxide (ZnO) act as photocatalysts, after they have been powdered to nanoparticles. Ultraviolet (UV) radiation is an agent that determines their excitation. Methods using photocatalytic properties of nanosized TiO2 and ZnO prove to be highly efficient in inactivation of infectious agents. Therefore, they are being applied on a growing scale. AOP-based disinfection is regarded as a very promising tool that might help overcome problems in food hygiene and public health protection. The susceptibility of infectious agents to photocatalylic processes can be generally arranged in the following order: viruses > prions > Gram-negative bacteria > Gram-positive bacteria > yeasts > molds.

49 CFR 40.329 - What information must laboratories, MROs, and other service agents release to employees?

Code of Federal Regulations, 2010 CFR

2010-10-01

... other service agents release to employees? 40.329 Section 40.329 Transportation Office of the Secretary... Confidentiality and Release of Information § 40.329 What information must laboratories, MROs, and other service agents release to employees? (a) As an MRO or service agent you must provide, within 10 business days of...

76 FR 62412 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-07

... for Registration, (2) Request to Transfer Select Agent or Toxin, (3) Report of Theft, Loss, or Release..., or Release of Select Agent and Toxin, (4) Report of Identification of Select Agent or Toxin. There... Release of Select Agent or Toxin; (4) Report of Identification of Select Agent or Toxin; and (5) Request...

Young Children’s Exposures to Molds and Consumer Product Ingredients in their Homes

EPA Science Inventory

Young children’s physiology and unique interactions with the environment have been shown to influence their exposures to common chemical and biological agents. Many types of consumer products are present in homes, resulting in the potential for direct and indirect exposures...

Daphnia swarms: from single agent dynamics to collective vortex formation

NASA Astrophysics Data System (ADS)

Ordemann, Anke; Balazsi, Gabor; Caspari, Elizabeth; Moss, Frank

2003-05-01

Swarm theories have become fashionable in theoretical physics over the last decade. They span the range of interactions from individual agents moving in a mean field to coherent collective motions of large agent populations, such as vortex-swarming. But controlled laboratory tests of these theories using real biological agents have been problematic due primarily to poorly known agent-agent interactions (in the case of e.g. bacteria and slime molds) or the large swarm size (e.g. for flocks of birds and schools of fish). Moreover, the entire range of behaviors from single agent interactions to collective vortex motions of the swarm have here-to-fore not been observed with a single animal. We present the results of well defined experiments with the zooplankton Daphnia in light fields showing this range of behaviors. We interpret our results with a theory of the motions of self-propelled agents in a field.

PCPPI: a comprehensive database for the prediction of Penicillium-crop protein-protein interactions

USDA-ARS?s Scientific Manuscript database

Penicillium expansum, the causal agent of blue mold, is one of the most prevalent postharvest pathogens infecting a wide range of crops after harvest. In response, crops have evolved various defense systems to protect themselves against this and other pathogens. Penicillium-crop interaction is a m...

Hybrid composite based on poly(vinyl alcohol) and fillers from renewable resources

USDA-ARS?s Scientific Manuscript database

Hybrid composite laminates consisting of polyvinyl alcohol (PVA) as continuous phase (33% by weight) and lignocellulosic fillers, derived from sugarcane bagasse, apple and orange waste (22% by weight) were molded in a carver press in the presence of water and glycerol such as platicizers agents. Cor...

21 CFR 172.880 - Petrolatum.

Code of Federal Regulations, 2010 CFR

2010-04-01

... bakery products; as release agent and lubricant With white mineral oil, not to exceed 0.15 percent of bakery product. In confectionery; as release agent and as sealing and polishing agent Not to exceed 0.2 percent of confectionery. In dehydrated fruits and vegetables; as release agent Not to exceed 0.02 percent...

Invasive pulmonary Aspergillosis in organ transplants--Focus on lung transplants.

PubMed

Geltner, Christian; Lass-Flörl, Cornelia

2016-03-01

Infections with filamentous fungi are common in transplant recipients. The risk for aspergillosis and other invasive pulmonary mycosis (IPM) is high in patients undergoing stem cell and lung transplantations. The mortality rates range from 20% to 60% and depend on a number of risk factors. The typical manifestations of IPM are lung infiltrates, consolidations, and fungal tracheobronchitis. The most common infectious agent is Aspergillus fumigatus. Infections caused by non-Aspergillus molds are more frequent for various reasons. The species distribution of non-Aspergillus molds varies in different locations. Furthermore, infections caused by Mucor and Penicillium are increasing, as are infections caused by species resistant to azoles and amphotericin B. Most centers use antifungal prophylaxis with inhaled amphotericin B or oral azoles. Early diagnosis and therapy is crucial. Reliable information on the local microbiological spectrum is a prerequisite for the effective treatment of molds with primary or secondary resistance to antimycotic drugs. Copyright © 2015 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

Smart Swarms of Bacteria-Inspired Agents with Performance Adaptable Interactions

PubMed Central

Shklarsh, Adi; Ariel, Gil; Schneidman, Elad; Ben-Jacob, Eshel

2011-01-01

Collective navigation and swarming have been studied in animal groups, such as fish schools, bird flocks, bacteria, and slime molds. Computer modeling has shown that collective behavior of simple agents can result from simple interactions between the agents, which include short range repulsion, intermediate range alignment, and long range attraction. Here we study collective navigation of bacteria-inspired smart agents in complex terrains, with adaptive interactions that depend on performance. More specifically, each agent adjusts its interactions with the other agents according to its local environment – by decreasing the peers' influence while navigating in a beneficial direction, and increasing it otherwise. We show that inclusion of such performance dependent adaptable interactions significantly improves the collective swarming performance, leading to highly efficient navigation, especially in complex terrains. Notably, to afford such adaptable interactions, each modeled agent requires only simple computational capabilities with short-term memory, which can easily be implemented in simple swarming robots. PMID:21980274

Smart swarms of bacteria-inspired agents with performance adaptable interactions.

PubMed

Shklarsh, Adi; Ariel, Gil; Schneidman, Elad; Ben-Jacob, Eshel

2011-09-01

Collective navigation and swarming have been studied in animal groups, such as fish schools, bird flocks, bacteria, and slime molds. Computer modeling has shown that collective behavior of simple agents can result from simple interactions between the agents, which include short range repulsion, intermediate range alignment, and long range attraction. Here we study collective navigation of bacteria-inspired smart agents in complex terrains, with adaptive interactions that depend on performance. More specifically, each agent adjusts its interactions with the other agents according to its local environment--by decreasing the peers' influence while navigating in a beneficial direction, and increasing it otherwise. We show that inclusion of such performance dependent adaptable interactions significantly improves the collective swarming performance, leading to highly efficient navigation, especially in complex terrains. Notably, to afford such adaptable interactions, each modeled agent requires only simple computational capabilities with short-term memory, which can easily be implemented in simple swarming robots.

Analysis of Silicones Released from Household Items and Baby Articles by Direct Analysis in Real Time-Mass Spectrometry

NASA Astrophysics Data System (ADS)

Gross, Jürgen H.

2015-03-01

Direct analysis in real time-mass spectrometry (DART-MS) enables screening of articles of daily use made of polydimethylsiloxanes (PDMS), commonly known as silicone rubber, to assess their tendency to release low molecular weight silicone oligomers. DART-MS analyses were performed on a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Flexible silicone baking molds, a watch band, and a dough scraper, as baby articles different brands of pacifiers, nipples, and a teething ring have been examined. While somewhat arbitrarily chosen, the set can be regarded as representative of household items, baby articles, and other objects made of silicone rubber. For comparison, two brands of silicone septa and as blanks a glass slide and a latex pacifier were included. Differences between the objects were mainly observed in terms of molecular weight distribution and occasional release of other compounds in addition to PDMS. Other than that, all objects made of silicone rubber released significant amounts of PDMS during DART analysis. To provide a coarse quantification, a calibration based on silicone oil was established, which delivered PDMS losses from 20 μg to >100 μg during the 16-s period per measurement. Also, the extraction of baking molds in rapeseed oil demonstrated a PDMS release at the level of 1 μg mg-1. These findings indicate a potential health hazard from frequent or long-term use of such items. This work does not intend to blame certain brands of such articles. Nonetheless, a higher level of awareness of this source of daily silicone intake is suggested.

Analysis of silicones released from household items and baby articles by direct analysis in real time-mass spectrometry.

PubMed

Gross, Jürgen H

2015-03-01

Direct analysis in real time-mass spectrometry (DART-MS) enables screening of articles of daily use made of polydimethylsiloxanes (PDMS), commonly known as silicone rubber, to assess their tendency to release low molecular weight silicone oligomers. DART-MS analyses were performed on a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Flexible silicone baking molds, a watch band, and a dough scraper, as baby articles different brands of pacifiers, nipples, and a teething ring have been examined. While somewhat arbitrarily chosen, the set can be regarded as representative of household items, baby articles, and other objects made of silicone rubber. For comparison, two brands of silicone septa and as blanks a glass slide and a latex pacifier were included. Differences between the objects were mainly observed in terms of molecular weight distribution and occasional release of other compounds in addition to PDMS. Other than that, all objects made of silicone rubber released significant amounts of PDMS during DART analysis. To provide a coarse quantification, a calibration based on silicone oil was established, which delivered PDMS losses from 20 μg to >100 μg during the 16-s period per measurement. Also, the extraction of baking molds in rapeseed oil demonstrated a PDMS release at the level of 1 μg mg(-1). These findings indicate a potential health hazard from frequent or long-term use of such items. This work does not intend to blame certain brands of such articles. Nonetheless, a higher level of awareness of this source of daily silicone intake is suggested.

Native Killer Yeasts as Biocontrol Agents of Postharvest Fungal Diseases in Lemons.

PubMed

Perez, María Florencia; Contreras, Luciana; Garnica, Nydia Mercedes; Fernández-Zenoff, María Verónica; Farías, María Eugenia; Sepulveda, Milena; Ramallo, Jacqueline; Dib, Julián Rafael

2016-01-01

Economic losses caused by postharvest diseases represent one of the main problems of the citrus industry worldwide. The major diseases affecting citrus are the "green mold" and "blue mold", caused by Penicillium digitatum and P. italicum, respectively. To control them, synthetic fungicides are the most commonly used method. However, often the emergence of resistant strains occurs and their use is becoming more restricted because of toxic effects and environmental pollution they generate, combined with trade barriers to international markets. The aim of this work was to isolate indigenous killer yeasts with antagonistic activity against fungal postharvest diseases in lemons, and to determine their control efficiency in in vitro and in vivo assays. Among 437 yeast isolates, 8.5% show to have a killer phenotype. According to molecular identification, based on the 26S rDNA D1/D2 domain sequences analysis, strains were identified belonging to the genera Saccharomyces, Wickerhamomyces, Kazachstania, Pichia, Candida and Clavispora. Killers were challenged with pathogenic molds and strains that caused the maximum in vitro inhibition of P. digitatum were selected for in vivo assays. Two strains of Pichia and one strain of Wickerhamomyces depicted a significant protection (p <0.05) from decay by P. digitatum in assays using wounded lemons. Thus, the native killer yeasts studied in this work showed to be an effective alternative for the biocontrol of postharvest fungal infections of lemons and could be promising agents for the development of commercial products for the biological control industry.

Fungal inactivation by Mexican oregano (Lippia berlandieri Schauer) essential oil added to amaranth, chitosan, or starch edible films.

PubMed

Avila-Sosa, Raúl; Hernández-Zamoran, Erika; López-Mendoza, Ingrid; Palou, Enrique; Jiménez Munguía, María Teresa; Nevárez-Moorillón, Guadalupe Virginia; López-Malo, Aurelio

2010-04-01

Edible films can incorporate antimicrobial agents to provide microbiological stability, since they can be used as carriers of a wide number of additives that can extend product shelf life and reduce the risk of pathogenic bacteria growth on food surfaces. Addition of antimicrobial agents to edible films offers advantages such as the use of low antimicrobial concentrations and low diffusion rates. The aim of this study was to evaluate inhibition of Aspergillus niger and Penicillium spp. by selected concentrations of Mexican oregano (Lippia berlandieri Schauer) essential oil added to amaranth, chitosan, or starch edible films. Oregano essential oil was characterized by gas chromatography-mass spectrometry (GC/MS) analysis. Amaranth, chitosan, and starch edible films were formulated with essential oil concentrations of 0%, 0.25%, 0.50%, 0.75%, 1%, 2%, and 4%. Mold radial growth was evaluated inoculating spores in 2 ways: edible films were placed over inoculated agar, Film/Inoculum mode (F/I), or the edible films were first placed in the agar and then films were inoculated, Inoculum/Film mode (I/F). The modified Gompertz model adequately described growth curves. There was no significant difference (P > 0.05) in growth parameters between the 2 modes of inoculation. Antifungal effectiveness of edible films was starch > chitosan > amaranth. In starch edible films, both studied molds were inhibited with 0.50% of essential oil. Edible films added with Mexican oregano essential oil could improve the quality of foods by controlling surface growth of molds.

Native Killer Yeasts as Biocontrol Agents of Postharvest Fungal Diseases in Lemons

PubMed Central

Garnica, Nydia Mercedes; Fernández-Zenoff, María Verónica; Farías, María Eugenia; Sepulveda, Milena; Ramallo, Jacqueline; Dib, Julián Rafael

2016-01-01

Economic losses caused by postharvest diseases represent one of the main problems of the citrus industry worldwide. The major diseases affecting citrus are the "green mold" and "blue mold", caused by Penicillium digitatum and P. italicum, respectively. To control them, synthetic fungicides are the most commonly used method. However, often the emergence of resistant strains occurs and their use is becoming more restricted because of toxic effects and environmental pollution they generate, combined with trade barriers to international markets. The aim of this work was to isolate indigenous killer yeasts with antagonistic activity against fungal postharvest diseases in lemons, and to determine their control efficiency in in vitro and in vivo assays. Among 437 yeast isolates, 8.5% show to have a killer phenotype. According to molecular identification, based on the 26S rDNA D1/D2 domain sequences analysis, strains were identified belonging to the genera Saccharomyces, Wickerhamomyces, Kazachstania, Pichia, Candida and Clavispora. Killers were challenged with pathogenic molds and strains that caused the maximum in vitro inhibition of P. digitatum were selected for in vivo assays. Two strains of Pichia and one strain of Wickerhamomyces depicted a significant protection (p <0.05) from decay by P. digitatum in assays using wounded lemons. Thus, the native killer yeasts studied in this work showed to be an effective alternative for the biocontrol of postharvest fungal infections of lemons and could be promising agents for the development of commercial products for the biological control industry. PMID:27792761

Potato Dextrose Agar Antifungal Susceptibility Testing for Yeasts and Molds: Evaluation of Phosphate Effect on Antifungal Activity of CMT-3

PubMed Central

Liu, Yu; Tortora, George; Ryan, Maria E.; Lee, Hsi-Ming; Golub, Lorne M.

2002-01-01

The broth macrodilution method (BMM) for antifungal susceptibility testing, approved by the National Committee for Clinical Laboratory Standards (NCCLS), was found to have deficiencies in testing of the antifungal activity of a new type of antifungal agent, a nonantibacterial chemically modified tetracycline (CMT-3). The high content of phosphate in the medium was found to greatly increase the MICs of CMT-3. To avoid the interference of phosphate in the test, a new method using potato dextrose agar (PDA) as a culture medium was developed. Eight strains of fungi, including five American Type Culture Collection strains and three clinical isolates, were used to determine the MICs of amphotericin B and itraconazole with both the BMM and the PDA methods. The MICs of the two antifungal agents determined with the PDA method showed 99% agreement with those determined with the BMM method within 1 log2 dilution. Similarly, the overall reproducibility of the MICs with the PDA method was above 97%. Three other antifungal agents, fluconazole, ketoconazole, and CMT-3, were also tested in parallel against yeasts and molds with both the BMM and the PDA methods. The MICs of fluconazole and ketoconazole determined with the PDA method showed 100% agreement within 1 log2 dilution of those obtained with the BMM method. However, the MICs of CMT-3 determined with the BMM method were as high as 128 times those determined with the PDA method. The effect of phosphate on the antifungal activity of CMT-3 was evaluated by adding Na2HPO4 to PDA in the new method. It was found that the MIC of CMT-3 against a Penicillium sp. increased from 0.5 μg/ml (control) to 2.0 μg/ml when the added phosphate was used at a concentration of 0.8 mg/ml, indicating a strong interference of Na2HPO4 with the antifungal activity of CMT-3. Except for fluconazole, all the other antifungal agents demonstrated clear end points among the yeasts and molds tested. Nevertheless, with its high reproducibility, good agreement with NCCLS proposed MIC ranges, and lack of interference of phosphate, the PDA method shows promise as a useful assay for antifungal susceptibility testing and screening for new antifungal agents, especially for drugs that may be affected by high (supraphysiologic) phosphate concentrations. PMID:11959582

An unusual case of anaphylaxis. Mold in pancake mix.

PubMed

Bennett, A T; Collins, K A

2001-09-01

Anaphylactic reactions involve contact with an antigen that evokes an immune reaction that is harmful. This type of reaction is a rapidly developing immunologic reaction termed a type I hypersensitivity reaction. The antigen complexes with an IgE antibody that is bound to mast cells and basophils in a previously sensitized individual. Upon re-exposure, vasoactive and spasmogenic substances are released that act on vessels and smooth muscle. The reaction can be local or systemic and may be fatal. The authors report the death of a 19-year-old white male who had a history of "multiple allergies," including pets, molds, and penicillin. One morning, he and his friends made pancakes with a packaged mix that had been opened and in the cabinet for approximately 2 years. The friends stopped eating the pancakes because they said that they tasted like "rubbing alcohol." The decedent continued to eat the pancakes and suddenly became short of breath. He was taken to a nearby clinic, where he became unresponsive and died. At autopsy, laryngeal edema and hyperinflated lungs with mucous plugging were identified. Microscopically, edema and numerous degranulating mast cells were identified in the larynx. The smaller airways contained mucus, and findings of chronic asthma were noted. Serum tryptase was elevated at 14.0 ng/ml. The pancake mix was analyzed and found to contain a total mold count of 700/g of mix as follows: Penicillium, Fusarium, Mucor, and Aspergillus. Witness statements indicate that the decedent ate two pancakes; thus he consumed an approximate mold count of 21,000. The decedent had a history of allergies to molds and penicillin, and thus was allergic to the molds in the pancake mix. The authors present this unusual case of anaphylaxis and a review of the literature.

Onychomycosis due to nondermatophytic molds.

PubMed

Hwang, Sung Min; Suh, Moo Kyu; Ha, Gyoung Yim

2012-05-01

Although there have been many studies about onychomycosis due to nondermatophytic molds (NDM), few studies about etiologic agents including NDM in onychomycosis have been reported in Korea. This study investigated onychomycosis due to NDM in the Gyeongju area of Korea. In the 10-year period from 1999~2009, we reviewed 59 patients with onychomycosis due to NDM. The etiologic agents were identified by cultures on Sabouraud's Dextrose agar with and without cycloheximide. In some cases, internal transcribed spacer sequence analysis was done. NDM isolated considered pathogens when the presence of fungal elements was identified by direct microscopy observation and in follow-up cultures yielding the same fungi. Onychomycosis due to NDM comprised 2.3% of all onychomycosis. Of the 59 patients with onychomycosis due to NDM, 84.7% were toenail onychomycosis and 15.3% were fingernail onychomycosis. The incidence rate was highest in the fifth decade (27.1%). The ratio of male to female patients was 1:1.6. The frequency of associated diseases, in descending order, was hypertension, diabetes mellitus, and cerebral hematoma. Distal and lateral subungual onychomycosis (86.4%) was the most common clinical type of onychomycosis. Aspergillus spp. was the most frequently isolated etiologic agent of onychomycosis due to NDM (83.0%). Other causative agents were Scopulariopsis brevicaulis (10.2%), Acremonium spp. (3.4%), Fusarium solani (1.7%), and Chaetomium globosum (1.7%). Because of the increase in onychomycosis due to NDM, we suggest the need of a careful mycological examination in patients with onychomycosis.

Development and characterization of a dynamic lesion phantom for the quantitative evaluation of dynamic contrast-enhanced MRI.

PubMed

Freed, Melanie; de Zwart, Jacco A; Hariharan, Prasanna; Myers, Matthew R; Badano, Aldo

2011-10-01

To develop a dynamic lesion phantom that is capable of producing physiological kinetic curves representative of those seen in human dynamic contrast-enhanced MRI (DCE-MRI) data. The objective of this phantom is to provide a platform for the quantitative comparison of DCE-MRI protocols to aid in the standardization and optimization of breast DCE-MRI. The dynamic lesion consists of a hollow, plastic mold with inlet and outlet tubes to allow flow of a contrast agent solution through the lesion over time. Border shape of the lesion can be controlled using the lesion mold production method. The configuration of the inlet and outlet tubes was determined using fluid transfer simulations. The total fluid flow rate was determined using x-ray images of the lesion for four different flow rates (0.25, 0.5, 1.0, and 1.5 ml/s) to evaluate the resultant kinetic curve shape and homogeneity of the contrast agent distribution in the dynamic lesion. High spatial and temporal resolution x-ray measurements were used to estimate the true kinetic curve behavior in the dynamic lesion for benign and malignant example curves. DCE-MRI example data were acquired of the dynamic phantom using a clinical protocol. The optimal inlet and outlet tube configuration for the lesion molds was two inlet molds separated by 30° and a single outlet tube directly between the two inlet tubes. X-ray measurements indicated that 1.0 ml/s was an appropriate total fluid flow rate and provided truth for comparison with MRI data of kinetic curves representative of benign and malignant lesions. DCE-MRI data demonstrated the ability of the phantom to produce realistic kinetic curves. The authors have constructed a dynamic lesion phantom, demonstrated its ability to produce physiological kinetic curves, and provided estimations of its true kinetic curve behavior. This lesion phantom provides a tool for the quantitative evaluation of DCE-MRI protocols, which may lead to improved discrimination of breast cancer lesions.

Antifungal activity by vapor contact of essential oils added to amaranth, chitosan, or starch edible films.

PubMed

Avila-Sosa, Raúl; Palou, Enrique; Jiménez Munguía, María Teresa; Nevárez-Moorillón, Guadalupe Virginia; Navarro Cruz, Addí Rhode; López-Malo, Aurelio

2012-02-01

Antimicrobial agents can be incorporated into edible films to provide microbiological stability, since films can be used as carriers of a variety of additives to extend product shelf life and reduce the risk of microbial growth on food surfaces. Addition of antimicrobial agents to edible films offers advantages such as the use of small antimicrobial concentrations and low diffusion rates. The aim of this study was to evaluate inhibition by vapor contact of Aspergillus niger and Penicillium digitatum by selected concentrations of Mexican oregano (Lippia berlandieri Schauer), cinnamon (Cinnamomum verum) or lemongrass (Cymbopogon citratus) essential oils (EOs) added to amaranth, chitosan, or starch edible films. Essential oils were characterized by gas chromatography-mass spectrometry (GC/MS) analysis. Amaranth, chitosan and starch edible films were formulated with essential oil concentrations of 0.00, 0.25, 0.50, 0.75, 1.00, 2.00, or 4.00%. Antifungal activity was evaluated by determining the mold radial growth on agar media inoculated with A. niger and P. digitatum after exposure to vapors arising from essential oils added to amaranth, chitosan or starch films using the inverted lid technique. The modified Gompertz model adequately described mold growth curves (mean coefficient of determination 0.991 ± 0.05). Chitosan films exhibited better antifungal effectiveness (inhibition of A. niger with 0.25% of Mexican oregano and cinnamon EO; inhibition of P. digitatum with 0.50% EOs) than amaranth films (2.00 and 4.00% of cinnamon and Mexican oregano EO were needed to inhibit the studied molds, respectively). For chitosan and amaranth films a significant increase (p<0.05) of lag phase was observed among film concentrations while a significant decrease (p<0.05) of maximum specific growth was determined. Chitosan edible films incorporating Mexican oregano or cinnamon essential oil could improve the quality of foods by the action of the volatile compounds on surface growth of molds. Copyright © 2011. Published by Elsevier B.V.

Cell Structure Evolution of Aluminum Foams Under Reduced Pressure Foaming

NASA Astrophysics Data System (ADS)

Cao, Zhuokun; Yu, Yang; Li, Min; Luo, Hongjie

2016-09-01

Ti-H particles are used to increase the gas content in aluminum melts for reduced pressure foaming. This paper reports on the RPF process of AlCa alloy by adding TiH2, but in smaller amounts compared to traditional process. TiH2 is completely decomposed by stirring the melt, following which reduced pressure is applied. TiH2 is not added as the blowing agent; instead, it is added for increasing the H2 concentration in the liquid AlCa melt. It is shown that pressure change induces further release of hydrogen from Ti phase. It is also found that foam collapse is caused by the fast bubble coalescing during pressure reducing procedure, and the instability of liquid film is related to the significant increase in critical thickness of film rupture. A combination of lower amounts of TiH2, coupled with reduced pressure, is another way of increasing hydrogen content in the liquid aluminum. A key benefit of this process is that it provides time to transfer the molten metal to a mold and then apply the reduced pressure to produce net shape foam parts.

Total airborne mold particle sampling: evaluation of sample collection, preparation and counting procedures, and collection devices.

PubMed

Godish, Diana; Godish, Thad

2008-02-01

This study was conducted to evaluate (i) procedures used to collect, prepare, and count total airborne mold spore/particle concentrations, and (ii) the relative field performance of three commercially available total airborne mold spore/particle sampling devices. Differences between factory and laboratory airflow calibration values of axial fan-driven sampling instruments (used in the study) indicated a need for laboratory calibration using a mass flow meter to ensure that sample results were accurately calculated. An aniline blue-amended Calberla's solution adjusted to a pH of 4.2-4.4 provided good sample mounting/counting results using Dow Corning high vacuum grease, Dow Corning 280A adhesive, and Dow Corning 316 silicone release spray for samples collected using mini-Burkard and Allergenco samplers. Count variability among analysts was most pronounced in 5% counts of relatively low mold particle deposition density samples and trended downward with increased count percentage and particle deposition density. No significant differences were observed among means of 5, 10, and 20% counts and among analysts; a significant interaction effect was observed between analysts' counts and particle deposition densities. Significantly higher mini-Burkard and Air-O-Cell total mold spore/particle counts for 600x vs. 400x (1.9 and 2.3 x higher, respectively), 1000x vs. 600x (1.9 and 2.2 x higher, respectively) and 1000x vs. 400x (3.6 and 4.6 x higher, respectively) comparisons indicated that 1000x magnification counts best quantified total airborne mold spore/particles using light microscopy, and that lower magnification counts may result in unacceptable underreporting of airborne mold spore/particle concentrations. Modest but significantly higher (1.2x) total mold spore concentrations were observed with Allergenco vs. mini-Burkard samples collected in co-located, concurrently operated sampler studies; moderate but significantly higher mini-Burkard count values (1.4x) were observed in similar studies with Air-O-Cell samplers. These count differences were relatively small compared with the large differences observed among three count magnifications.

Nanocomposites from lignin-containing cellulose nanocrystals and poly(lactic acid)

Treesearch

Liqing Wei; Umesh Agarwal; Nicole Stark; Ronald Sabo

2017-01-01

Utilizing lignin-containing cellulose nanocrystals (HLCNCs) as reinforcing agents to poly(lactic acid) (PLA) for nanocomposites was studied for the first time. The PLA/HLCNCs nanocomposites were prepared by extrusion and injecting molding. The freeze-dried HLCNCs showed micron scale agglomerates. As indicated by the water contact angle measurements, the HLCNCs were...

Influence of water-soluble channeling agents on the release of diclofenac sodium from Irvingia malayana wax matrix tablets.

PubMed

Yotsawimonwat, Songwut; Charumanee, Suporn; Kaewvichit, Sayam; Sirithunyalug, Jakkapan; Sirisa-Ard, Panee; Piyamongkol, Sirivipa; Siangwong, Kulthawat

2017-05-01

Irvingia malayana wax (IW) is majorly composed of esters of medium chain fatty acids. Its melting point is low and closed to the body temperature. This study aimed at investigating the potential of IW as a matrix-forming agent and evaluate the effect of soluble channeling agents on the release of diclofenac sodium (DS) from IW matrix tablets. The preformulation study by infrared spectroscopy and differential scanning calorimetry showed no incompatibility between IW and DS or soluble channeling agents, namely PEG 4000, PEG 6000 and lactose. IW retarded the release of DS from the matrix tablets more efficiently than carnauba wax due to its greater hydrophobicity and its ability to become partial molten wax at 37° C. Factors affecting the release of DS from IW matrix were drug concentrations, and types and concentrations of channeling agents. The release of DS significantly improved when DS concentration reached approximately 33%. The fast dissolving channeling agent, lactose, could enhance the drug release rate more effectively than PEG 4000 and PEG 6000, respectively. The linear relationship between the DS release rate and the concentration of the chosen channeling agent, PEG 6000, was found (r 2 =0.9866).

Gastroresistant capsular device prepared by injection molding.

PubMed

Zema, Lucia; Loreti, Giulia; Melocchi, Alice; Maroni, Alessandra; Palugan, Luca; Gazzaniga, Andrea

2013-01-20

In the present work, the possibility of manufacturing by injection molding (IM) a gastro-resistant capsular device based on hydroxypropyl methyl cellulose acetate succinate (HPMCAS) was investigated. By performing as an enteric soluble container, such a device may provide a basis for the development of advantageous alternatives to coated dosage forms. Preliminarily, the processability of the selected thermoplastic polymer was evaluated, and the need for a plasticizer (polyethylene glycol 1500) in order to counterbalance the glassy nature of the molded items was assessed. However, some critical issues related to the physical/mechanical stability (shrinkage and warpage) and opening time of the device after the pH change were highlighted. Accordingly, an in-depth formulation study was carried out taking into account differing release modifiers potentially useful for enhancing the dissolution/disintegration rate of the capsular device at intestinal pH values. Capsule prototypes with thickness of 600 and 900 μm containing Kollicoat(®) IR and/or Explotab(®) CLV could be manufactured, and a promising performance was achieved with appropriate gastric resistance in pH 1.2 medium and break-up in pH 6.8 within 1h. These results would support the design of a dedicated mold for the development of a scalable manufacturing process. Copyright © 2012 Elsevier B.V. All rights reserved.

A novel design for storage of inner stress by colloidal processing on rock-like materials

NASA Astrophysics Data System (ADS)

Chen, Weichang; Wang, Sijing; Lekan Olatayo, Afolagboye; Fu, Huanran

2018-06-01

Inner stress exists in rocks, affecting rock engineering, yet has received very little attention and quantitative investigation because of uncertainty about its characteristics. Previous studies have suggested that the inner stresses of rock materials are closely related to their physical state variation. In this work, a novel mold was designed to simulate the storage process of inner stress in specimens composed of quartz sands and epoxy. Then, thermal tests were carried out to change the physical state of the specimens, and expansion of the specimens was monitored. The results indicated that inner stress could be partly locked by the mold and it could also be released by heating. It can be inferred from the analysis that one necessary condition of storage and release of inner stress is physical state variation. Additionally, by using an XRD method, the variations in the interplanar spacing of the quartz sands were detected, and the results reflect that inner stress could be locked-in aggregates (quartz sands) by a cement constraint (solid epoxy). The inner stress stored in quartz sands was calculated using height and interplanar spacing variations.

Antimicrobial effects of various nutrient electrolyte beverages. Final report, 1981-1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowley, D.B.; Johnson, D.; Shattuck, G.E.

The purpose of this study was to determine if Staphylococcus aureus, Saccharomyces cerevisiae, or the mold Aspergillus flavus could survive and muliply in Quenchade, Gatorade, and other electrolyte beverages to the point of creating a stability problem or a health hazard to NBC encapsulated personnel. During periods longer than 6 h, such individuals may need liquid energy and electrolyte supplements (Na+ and Cl-) capable of being consumed through the drinking tube of their protective mask. Although S. aureus was inactivated due to the low pH (ca. f3.0) of the electrolyte beverages, antimicrobial agents sodium benzoate or potassium sorbate had tomore » be added to prevent the multiplication of yeast and mold.« less

21 CFR 181.28 - Release agents.

Code of Federal Regulations, 2014 CFR

2014-04-01

... classified as release agents, when migrating from food-packaging material shall include: Dimethylpolysiloxane... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Release agents. 181.28 Section 181.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PRIOR-SANCTIONED...

Predicting the size-dependent tissue accumulation of agents released from vascular targeted nanoconstructs

NASA Astrophysics Data System (ADS)

de Tullio, Marco D.; Singh, Jaykrishna; Pascazio, Giuseppe; Decuzzi, Paolo

2014-03-01

Vascular targeted nanoparticles have been developed for the delivery of therapeutic and imaging agents in cancer and cardiovascular diseases. However, at authors' knowledge, a comprehensive systematic analysis on their delivery efficiency is still missing. Here, a computational model is developed to predict the vessel wall accumulation of agents released from vascular targeted nanoconstructs. The transport problem for the released agent is solved using a finite volume scheme in terms of three governing parameters: the local wall shear rate , ranging from to ; the wall filtration velocity , varying from to ; and the agent diffusion coefficient , ranging from to . It is shown that the percentage of released agent adsorbing on the vessel walls in the vicinity of the vascular targeted nanoconstructs reduces with an increase in shear rate , and with a decrease in filtration velocity and agent diffusivity . In particular, in tumor microvessels, characterized by lower shear rates () and higher filtration velocities (), an agent with a diffusivity (i.e. a 50 nm particle) is predicted to deposit on the vessel wall up to of the total released dose. Differently, drug molecules, exhibiting a smaller size and much higher diffusion coefficient (), are predicted to accumulate up to . In healthy vessels, characterized by higher and lower , the largest majority of the released agent is redistributed directly in the circulation. These data suggest that drug molecules and small nanoparticles only can be efficiently released from vascular targeted nanoconstructs towards the diseased vessel walls and tissue.

Aspergillus niger - a possible new etiopathogenic agent in Tinea capitis? Presentation of two cases.

PubMed

Chokoeva, Anastasiya Atanasova; Zisova, Liliya; Chorleva, Kristina; Tchernev, Georgi

2016-01-01

Tinea capitis is generally considered as the most frequent fungal infection in childhood, as it accounts for approximately 92% of all mycosis in children. The epidemiology of this disease varies widely ranging from antropophillic, zoophilic, and geophillic dermatophytes, as the main causative agent in different geographic areas, depending on several additional factors. Nowadays, the etiology is considered to vary with age, as well with gender, and general health condition. The former reported extraordinary Tinea capitis case reports have been replaced by original articles and researches dealing with progressively changing patterns in etiology and clinical manifestation of the disease. This fact is indicative that under the umbrella of the well-known disease there are facts still hidden for future revelations. Herein, we present two rare cases of Tinea capitis in children, which totally differ from the recently established pattern, in their clinical presentation, as well as in the etiological aspect, as we discuss this potential new etiological pattern of the disease, focusing on our retrospective and clinical observation. Collected data suggest that pathogenic molds should be considered as a potential source of infection in some geographic regions, which require total rationalization of the former therapeutic conception, regarding the molds' higher antimitotic resistance compared to dermatophytes. Molds-induced Tinea capitis should be also considered in clinically resistant and atypical cases, with further investigations of the antifungal susceptibility of the newest pathogens in the frame of the old disease. Further investigations are still needed to confirm or reject this proposal. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

Processing of poly(hydroxybutyrate-co-hydroxyvalerate)-based bionanocomposite foams using supercritical fluids

Treesearch

Alireza Javadi; Yottha Srithep; Craig C. Clemons; L-S. Turng; Shaoqin Gong

2012-01-01

Supercritical fluid (SCF) N2 was used as a physical foaming agent to fabricate microcellular injection-molded poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV)–poly(butylene adipate-co-terephthalate) (PBAT)–hyperbranched-polymer (HBP)–nanoclay (NC) bionanocomposites. The effects of incorporating HBP and NC on the morphological, mechanical, and...

Daily Life in Japanese High Schools. ERIC Digest.

ERIC Educational Resources Information Center

Johnson, Marcia L.; Johnson, Jeffrey R.

This ERIC Digest asserts that the Japanese education system is one of the most influential agents molding Japanese youth. This influence is especially great due to the large amount of time students spend in schools. Six topics examine aspects of daily high school life: (1) Getting to School; (2) At School; (3) Extracurricular Activities; (4)…

Effect of boron and phosphate compounds on physical, mechanical, and fire properties of wood-polypropylene composites

Treesearch

Nadir Ayrilmis; Turgay Akbulut; Turker Dundar; Robert H. White; Fatih Mengeloglu; Umit Buyuksari; Zeki Candan; Erkan Avci

2012-01-01

Physical, mechanical, and fire properties of the injection-molded wood flour/polypropylene composites incorporated with different contents of boron compounds; borax/boric acid and zinc borate, and phosphate compounds; mono and diammonium phosphates were investigated. The effect of the coupling agent content, maleic anhydride-grafted polypropylene, on the properties of...

Evaluation of host resistance to Botrytis bunch rot in Vitis spp. and its correlation with Botrytis leaf spot

USDA-ARS?s Scientific Manuscript database

Botrytis cinerea, the causal agent of Botrytis bunch rot and gray mold, is the number one postharvest disease of fresh grapes in the United States. Fungicide applications are used to manage the disease, but fungicide-resistant isolates are common and postharvest losses occur annually. Host resistanc...

The Biocontrol Efficacy of Streptomyces pratensis LMM15 on Botrytis cinerea in Tomato

PubMed Central

Lian, Qinggui; Zhang, Jing; Gan, Liang; Ma, Qing; Zong, Zhaofeng

2017-01-01

LMM15, an actinomycete with broad spectrum antifungal activity, was isolated from a diseased tomato leaf using the baiting technique. A phylogenetic tree analysis based on similarity percentage of 16S rDNA sequences showed that the bacterium was 97.0% affiliated with the species Streptomyces pratensis. This strain was therefore coded as S. pratensis LMM15. The ferment filtrate of LMM15 had ability to inhibit mycelia growth of Botrytis cinerea and reduce lesion expansion of gray mold on detached leaves and fruits. In greenhouse experiments, both the fresh and dry weights of tomato seedlings were significantly increased with the increased concentrations of total chlorophyll. The incidence of tomato gray mold decreased by 46.35%; this was associated with the increase of proline content and malondialdehyde (MDA) and the changes in defense-related enzymes on tomato leaves when the strain was sprayed on the tomato leaves 24 h prior to inoculation with pathogens. This study showed that the strain S. pratensis LMM15 could be a potential agent for controlling tomato gray mold. PMID:29318156

Volatile organic compounds from Wickerhamomyces anomalus, Metschnikowia pulcherrima and Saccharomyces cerevisiae inhibit growth of decay causing fungi and control postharvest diseases of strawberries.

PubMed

Oro, Lucia; Feliziani, Erica; Ciani, Maurizio; Romanazzi, Gianfranco; Comitini, Francesca

2018-01-16

The effectiveness of Wickerhamomyces anomalus, Metschnikowia pulcherrima and Saccharomyces cerevisiae as biocontrol agents on postharvest decay of strawberry (Fragaria x ananassa, cv. 'Alba') fruit, and their inhibitory activities on some decay-causing fungi were evaluated. Volatile organic compounds from these yeasts decreased mycelial growth of Botrytis cinerea by 69%, and by less for Monilinia fructicola, Alternaria alternata, Aspergillus carbonarius, Penicillium digitatum, Cladosporium spp., and Colletotrichum spp. Strawberry fruit exposed to 6-day-old liquid cultures of W. anomalus, M. pulcherrima and S. cerevisiae for 48h showed 89%, 40%, and 32% reductions, respectively, in gray mold McKinney Index. Vapours of ethyl acetate, the main volatile organic compound of these yeasts, completely inhibited B. cinerea growth at 8.97mg/cm 3 , and suppressed gray mold on strawberry fruit at 0.718mg/cm 3 . The biocontrol activities of these yeasts can be ascribed to ethyl acetate, which can be used for control of postharvest gray mold of strawberry fruit. Copyright © 2017 Elsevier B.V. All rights reserved.

The application of bioactive compounds from the food industry to control mold growth in indoor waterborne coatings.

PubMed

Bellotti, N; Salvatore, L; Deyá, C; Del Panno, M T; del Amo, B; Romagnoli, R

2013-04-01

Microbial growth in indoor environments creates health problems, especially in people with asthma; approximately 80% of these patients are allergic to mold. Antimicrobial coatings are formulated to generate surfaces that are easy to clean and may also incorporate active agents, commonly called biocides, which inhibit microbial colonization, subsequent growth and bio-deterioration of the substrates. Some research lines seek to replace traditional organometallic and organochlorines biocides with environmentally acceptable ones. The aim of this research was, primarily, to explore the possible application of different compounds used in food industry like preservatives to be used as antimicrobial additives for antimicrobial coatings. Four biocides were tested against two different ambient molds isolated from an interior painted wall (Chaetomium globosum and Alternaria alternate). The selected biocides were zinc salicylate, zinc benzoate, calcium benzoate and potassium sorbate. The resulting paints were subjected to biological and physical tests (viscosity, hiding power, humidity absorption and biocides leaching rate). Bioassays revealed that zinc benzoate and zinc salicylate resulted active against both fungi. Copyright © 2012 Elsevier B.V. All rights reserved.

LFT foam - Lightweight potential for semi-structural components through the use of long-glass-fiber-reinforced thermoplastic foams

NASA Astrophysics Data System (ADS)

Roch, A.; Huber, T.; Henning, F.; Elsner, P.

2014-05-01

Investigations on PP-LGF30 foam sandwiches have been carried out using different manufacturing processes: standard injection molding, MuCell® and LFT-D foam. Both chemical and physical blowing agents were applied. Precision mold opening (breathing mold technology) was selected for the foaming process. The integral foam design, which can be conceived as a sandwich structure, helps to save material in the neutral axis area and maintains a distance between load-bearing, unfoamed skin layers. The experiments showed that, at a constant mass per unit area, integral foams have a significantly higher flexural rigidity than compact components, due to their greater area moment of inertia after foaming: with an increase of the wall thickness from 3.6 mm to 4.4 mm compared to compact construction, the flexural rigidity increased by 75 %. With a final wall thickness of 5.8 mm an increase of 300 % was measured. Compared to non-reinforced components that show significant embrittlement during foaming, the energy absorption capacity (impact strength) of LFT foam components remains almost constant.

Advanced Glycation End Products: Association with the Pathogenesis of Diseases and the Current Therapeutic Advances.

PubMed

Ajith, Thekkuttuparambil A; Vinodkumar, Puzhikunathu

2016-01-01

Advanced glycation end products (AGE) such as N-ε-carboxy-ethyl-lysine (CEL), N-ε-carboxy-methyl-lysine (CML), imidazolone, methyl-glyoxal-lysine dimer (MOLD), glyoxal-lysine dimer (GOLD), pyrraline and pentosidine have been imparted in the development and worsening of complications of diabetes. They are also involved in atherosclerosis, normal aging process, arthritis, cancer and progression of age-related neurodegenerative diseases like Alzheimer`s disease. Endogenously, they are formed by nonenzymatic glycation by aldoses/ketoses to form intermediate precursor that were slowly converted into AGE. A positive correlation was observed with the level of AGEs formation and progression of the diseases. Exogenously, they formed in foods when they were cooked at very high temperature. AGEs can interact with the cell surface receptors of AGE (RAGE) to release cytokines, free radicals as well as directly modify the extracellular matrix and action of hormones. Hence, the mechanism of AGE association with pathogenesis of diseases can be ascribed mainly to the generated cytokines and free radicals. Second type of receptors such as AGE receptor-1, 2 and 3 were more specific and involved in their detoxification and clearance. Therapeutic agents were used to inhibit AGEs formation, traps the reactive carbonyl intermediate precursors, interfering with Amadori`s products, cross-link breaker and low molecular weight inhibitors of RAGE had been described as well. Despite the several therapeutic agents described so far, none of them have proven to be recommended for clinical use. Furthermore, no methods or standard units were accepted universally to measure AGEs are existing. This review discusses AGEs formation, association with diseases and therapeutic agents to alleviate them.

Ultrasonic mixing of epoxy curing agents

NASA Technical Reports Server (NTRS)

Hodges, W. T.; St.clair, T. L.

1983-01-01

A new technique for mixing solid curing agents into liquid epoxy resins using ultrasonic energy was developed. This procedure allows standard curing agents such as 4,4 prime-diaminodiphenyl sulfone (4,4 prime-DDS) and its 3,3 prime-isomer, (3,3 prime-DDS) to be mixed without prior melting of the curing agent. It also allows curing agents such as 4,4 prime-diaminodiphenyl sulfone (4,4 prime-DDS) and its 3,3 prime-isomer, (3,3 prime-DDS) to be mixed without prior melting of the curing agent. It also allows curing agents with very high melt temperatures such as 4,4 prime-diaminobenzophenone (4,4 prime-DABP) (242 C) to be mixed without premature curing. Four aromatic diamines were ultrasonically blended into MY-720 epoxy resin. These were 4,4 prime-DDS; 3,3 prime-DDA; 4,4 prime-DABP and 3,3 prime-DABP. Unfilled moldings were cast and cured for each system and their physical and mechanical properties compared.

Invited review: Bioactive compounds produced during cheese ripening and health effects associated with aged cheese consumption.

PubMed

Santiago-López, Lourdes; Aguilar-Toalá, Jose E; Hernández-Mendoza, Adrián; Vallejo-Cordoba, Belinda; Liceaga, Andrea M; González-Córdova, Aarón F

2018-05-01

Traditionally, cheese is manufactured by converting fluid milk to a semisolid mass through the use of a coagulating agent, such as rennet, acid, heat plus acid, or a combination thereof. Cheese can vary widely in its characteristics, including color, aroma, texture, flavor, and firmness, which can generally be attributed to the production technology, source of the milk, moisture content, and length of aging, in addition to the presence of specific molds, yeast, and bacteria. Among the most important bacteria, lactic acid bacteria (LAB) play a critical role during the cheese-making process. In general, LAB contain cell-envelope proteinases that contribute to the proteolysis of cheese proteins, breaking them down into oligopeptides that can be subsequently taken up by cells via specific peptide transport systems or further degraded into shorter peptides and amino acids through the collaborative action of various intracellular peptidases. Such peptides, amino acids, and their derivatives contribute to the development of texture and flavor in the final cheese. In vitro and in vivo assays have demonstrated that specific sequences of released peptides exhibit biological properties including antioxidant, antimicrobial, anti-inflammatory, immunomodulatory, and analgesic/opioid activity, in addition to angiotensin-converting enzyme inhibition and antiproliferative activity. Some LAB also produce functional lipids (e.g., conjugated linoleic acid) with anti-inflammatory and anticarcinogenic activity, synthesize vitamins and antimicrobial peptides (bacteriocins), or release γ-aminobutyric acid, a nonprotein amino acid that participates in physiological functions, such as neurotransmission and hypotension induction, with diuretic effects. This review provides an overview of the main bioactive components present or released during the ripening process of different types of cheese. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Preventing Growth Of Barnacles On Propellers

NASA Technical Reports Server (NTRS)

Parrish, Kemp L.

1993-01-01

Possible to prevent barnacles and other marine life from obtaining firm bonds on propellers and other metal parts by coating parts with NEDOX (or equivalent) cavitation-resistant material. Available in several forms; one that works best is mold-release coating. Also provides improved surface hardness, protection against electrolysis, better resistance to abrasion, and less friction between propellers and water.

Aeroplastic, New Composite Materials with Reduced Heat Transfer and Increased Flame Retardancy

NASA Technical Reports Server (NTRS)

Williams, Martha K.; Smith, Trent M.; Nichols, James D.; Roberson, Luke B.; Tate, Lanetra C.

2015-01-01

A new composite system formulated using commodity grade and engineered grade polymers. The composites can be fabricated into fibers, molded, or otherwise processed into useable articles. Use of this technology reduces the thermal conductivity and peak heat releases rates of the base polymer between 20%-50% while maintaining or enhancing the mechanical properties..

3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds.

PubMed

Lee, Wonjae; Park, Jon

2016-07-06

Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues.

3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds

NASA Astrophysics Data System (ADS)

Lee, Wonjae; Park, Jon

2016-07-01

Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues.

3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds

PubMed Central

Lee, Wonjae; Park, Jon

2016-01-01

Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues. PMID:27381562

Development and evaluation of a suppository formulation containing Lactobacillus and its application in vaginal diseases.

PubMed

Kale, Vinita V; Trivedi, Rashmi V; Wate, Sanjay P; Bhusari, Kishor P

2005-11-01

Lactobacillus has long been considered the protective flora in the vagina that displaces and kills vaginal pathogens. Lactic acid, H2O2, and antibacterial agents such as lactocin and bacitracin produced by Lactobacillus act against the vaginal pathogens. The first objective of this research was to develop a local application pharmaceutical formulation of a vaginal suppository containing lyophilized culture of Lactobacillus. The second objective was to establish its in vivo performance by developing in vitro methods of evaluation. Lyophilized culture of Lactobacillus sporogenes was selected for this study. Three formulations of the suppositories were prepared by the molding method. Formulations I, II, and III contained cocoa butter, glycerinated gelatin, and PEG 1000 base, respectively. The prepared suppositories were characterized for physical properties. Assembly to simulate the application site was designed. Methods to evaluate the viability, production of lactic acid, and H2O2 produced by the released Lactobacillus at the application site were developed and the antagonistic activity was demonstrated. From the physical characteristics of the suppository formulations, the glycerinated gelatin suppository (formulation II) containing lyophilized Lactobacillus was found to be satisfactory. The developed assembly was satisfactory in simulating the application site. The Lactobacillus released was viable and exhibited the production of lactic acid, hydrogen peroxide, and antagonistic activity against the uropathogen. The suppository formulation containing Lactobacillus and the methods of its evaluation were successfully developed in this research work and have several applications in the vaginal diseases of women.

Aluminum-fly ash metal matrix composites for automotive parts. [Reports for April 1 to June 30, 1999, and July 1 to September 30, 1999

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiss, David; Purgert, Robert; Rhudy, Richard

1999-10-15

Some highlights are: (1) During this quarter's field trials, sand mold castings of parts and permanent mold tensile testing bars, K mold bars, and ingots were made from aluminum alloy-fly ash melts. (2) Another objective was met, i.e., to use class ''F'' type precipitator fly ash consisting of particle sizes less than 100 microns. It was possible to pour the composite melt into the sand mold through a filter. (3) Trials were run to determine the required amount of the wetting agent, magnesium, to ensure appropriate mixing of the aluminum alloy and fly ash. The magnesium content required to mixmore » ''F'' fly ash was much lower compared to that required to mix hybrid ''C-F'' fly ash in similar melts. Fly ash particles of less than 100 microns were mixed in aluminum melt. Large scale field trials were undertaken at Eck Industries with the goal of standardizing procedures for producing aluminum-fly ash composite melts and to analyze the structure and properties of the resulting material. Limited testing of tensile properties has been done on pressure die cast parts, and attempts are underway to improve the distribution of fly ash in both sand cast and pressure die cast samples. Eck Industries performed radiographic, heat treatment, and tensile tests on permanent mold cast tensile test bars. After fly ash mixing experiments, the Lanxide high speed-high shear mixer (originally designed for mixing Al-SiC melts) was employed in an attempt to avoid fly ash agglomeration. It led to demixing (instead of deagglomerating) of some fly ash. However, the permanent mold tensile bars poured after high shear mixing displayed good distribution of fly ash in castings. A modified impeller design is being considered for high speed-high shear mixing of aluminum-fly ash melts.« less

Housing Interventions and Control of Asthma-Related Indoor Biologic Agents: A Review of the Evidence

PubMed Central

Krieger, James; Jacobs, David E.; Ashley, Peter J.; Baeder, Andrea; Chew, Ginger L.; Dearborn, Dorr; Hynes, H. Patricia; Miller, J. David; Morley, Rebecca; Rabito, Felicia; Zeldin, DC

2014-01-01

Subject matter experts systematically reviewed evidence on the effectiveness of housing interventions that affect health outcomes, primarily asthma, associated with exposure to moisture, mold, and allergens. Three of the 11 interventions reviewed had sufficient evidence for implementation: multifaceted, in-home, tailored interventions for reducing asthma morbidity; integrated pest management to reduce cockroach allergen; and combined elimination of moisture intrusion and leaks and removal of moldy items to reduce mold and respiratory symptoms. Four interventions needed more field evaluation, one needed formative research, and three either had no evidence of effectiveness or were ineffective. The three interventions with sufficient evidence all applied multiple, integrated strategies. This evidence review shows that selected interventions that improve housing conditions will reduce morbidity from asthma and respiratory allergies. PMID:20689369

Housing interventions and control of asthma-related indoor biologic agents: a review of the evidence.

PubMed

Krieger, James; Jacobs, David E; Ashley, Peter J; Baeder, Andrea; Chew, Ginger L; Dearborn, Dorr; Hynes, H Patricia; Miller, J David; Morley, Rebecca; Rabito, Felicia; Zeldin, Darryl C

2010-01-01

Subject matter experts systematically reviewed evidence on the effectiveness of housing interventions that affect health outcomes, primarily asthma, associated with exposure to moisture, mold, and allergens. Three of the 11 interventions reviewed had sufficient evidence for implementation: multifaceted, in-home, tailored interventions for reducing asthma morbidity; integrated pest management to reduce cockroach allergen; and combined elimination of moisture intrusion and leaks and removal of moldy items to reduce mold and respiratory symptoms. Four interventions needed more field evaluation, 1 needed formative research, and 3 either had no evidence of effectiveness or were ineffective. The 3 interventions with sufficient evidence all applied multiple, integrated strategies. This evidence review shows that selected interventions that improve housing conditions will reduce morbidity from asthma and respiratory allergies.

Incipient flocculation molding: A new ceramic-forming technique

NASA Astrophysics Data System (ADS)

Arrasmith, Steven Reade

Incipient Flocculation Molding (IFM) was conceived as a new near-net-shape forming technique for ceramic components. It was hypothesized that the development of a temperature-dependent deflocculant would result in a forming technique that is flexible, efficient, and capable of producing a superior microstructure with improved mechanical properties from highly reactive, submicron ceramic powders. IFM utilizes a concentrated, nonaqueous, sterically stabilized ceramic powder and/or colloidal suspension which is injected into a non-porous mold. The suspension is then flocculated by destabilizing the suspension by lowering the temperature. Flocculation is both rapid and reversible. Cooling to -20°C produces a green body with sufficient strength for removal from the mold. The solvent is removed from the green body by evaporation. The dried green body is subsequently sintered to form a dense ceramic monolith. This is the first ceramic forming method based upon the manipulation of a sterically-stabilized suspension. To demonstrate IFM, the process of grafting polyethylene glycol (PEG), with molecular weights from 600 to 8000, to alumina powders was investigated. The maximum grafted amounts were achieved by the technique of dispersing the alumina powders in molten polymer at 195°C. The ungrafted PEG was then removed by repeated centrifuging and redispersion in fresh distilled water. The rheological behavior of suspensions of the PEG-grafted powders in water, 2-propanol and 2-butanol were characterized. All of the aqueous suspensions were shear thinning. The PEG 4600-grafted alumina powder aqueous suspensions were the most fluid. Sample rods and bars were molded from 52 vol% PEG-grafted alumina suspensions in 2-butanol. The best results were obtained with a preheated aluminum mold lubricated with a fluorinated oil mold-release. The samples were dried, sintered, and their microstructure and density were compared with sintered samples dry pressed from the same alumina powder. Densities and microstructures were quite similar to those obtained by dry pressing and sintering these powders. Dried green samples with densities of ca. 57% of theoretical sintered to >96% of theoretical density. This research has demonstrated IFM as a viable ceramic forming process which has potential to be developed into an industrial process. Further research is needed to determine preferred molding parameters, other possible polymer-solvent systems, and investigate the use of other ceramic powders. The concepts developed for IFM may have potential applications in other ceramic forming processes, such as extrusion and rapid prototyping.

PRODUCTION OF SLIP CAST CALCIA HOLLOWWARE

DOEpatents

Stoddard, S.D.; Nuckolls, D.E.; Cowan, R.E.

1963-12-31

A method for producing slip cast calcia hollow ware in which a dense calcia grain is suspended in isobutyl acetate or a mixture of tertiary amyl alcohol and o-xylene is presented. A minor amount of triethanolamine and oleic acid is added to the suspension vehicle as viscosity adjusting agents and the suspension is cast in a plaster mold, dried, and fired. (AEC)

34. DESPATCH CORE OVENS, GREY IRON FOUNDRY CORE ROOM, BAKES ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. DESPATCH CORE OVENS, GREY IRON FOUNDRY CORE ROOM, BAKES CORES THAT ARE NOT MADE ON HEATED OR COLD BOX CORE MACHINES, TO SET BINDING AGENTS MIXED WITH THE SAND CREATING CORES HARD ENOUGH TO WITHSTAND THE FLOW OF MOLTEN IRON INSIDE A MOLD. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

Chapter 4: Genetic Identification of Fungi Involved in Wood Decay

Treesearch

Grant Kirker

2014-01-01

Wood decay is a complex process that involves contributions from molds, bacteria, decay fungi, and often insects. The first step in the accurate diagnosis of decay is identification of the causal agents, but wood decay in the strictest sense (white and brown rot) is caused by cryptic fungal species that are very difficult to identify using traditional methods. Genetic...

Biocontrol Ability and Action Mechanism of Starmerella bacillaris (Synonym Candida zemplinina) Isolated from Wine Musts against Gray Mold Disease Agent Botrytis cinerea on Grape and Their Effects on Alcoholic Fermentation

PubMed Central

Lemos Junior, Wilson José Fernandes; Bovo, Barbara; Nadai, Chiara; Crosato, Giulia; Carlot, Milena; Favaron, Francesco; Giacomini, Alessio; Corich, Viviana

2016-01-01

Gray mold is one of the most important diseases of grapevine in temperate climates. This plant pathogen affects plant growth and reduces wine quality. The use of yeasts as biocontrol agents to apply in the vineyard have been investigated in recent years as an alternative to agrochemicals. In this work, fermenting musts obtained from overripe grape berries, therefore more susceptible to infection by fungal pathogens such as Botrytis cinerea, were considered for the selection of yeasts carrying antifungal activity. Thirty-six isolates were identified as Starmerella bacillaris, a species recently proven to be of enological interest. Among them 14 different strains were studied and antifungal activity against B. cinerea was demonstrated, for the first time, to be present in S. bacillaris species. The production of volatile organic compounds (VOCs), tested in vitro, was found to be the main responsible of S. bacillaris antifungal effects. All the strains were able to reduce B. cinerea decay on wounded grape berries artificially inoculated with gray mold. The colonization level of wound was very high reaching, after 5 days, a concentration of 106 cells per ml of grape juice obtained after berry crushing. At this cell concentration S. bacillaris strains were used to ferment synthetic and natural musts. The sequential yeast inoculation, performed by adding S. cerevisiae 48 h after S. bacillaris, was needed to complete sugar consumption and determined a significant increase in glicerol content and a reduction of ethanol and acetic acid concentrations. The high wound colonization ability, found in this work, together with the propensity to colonize grape berry and the interesting enological traits possessed by the selected S. bacillaris strains allow the use of this yeast as biocontrol agent on vine and grape berries with possible positive effects on must fermentation, although the presence of S. cerevisiae is needed to complete the fermentation process. This work introduces new possibilities in wine yeast selection programs in order to identify innovative wine yeasts that are simultaneously antifungal agents in vineyards and alternative wine starters for grape must fermentation and open new perspective to a more integrated strategy for increasing wine quality. PMID:27574517

Timolol maleate release from hyaluronic acid-containing model silicone hydrogel contact lens materials.

PubMed

Korogiannaki, Myrto; Guidi, Giuliano; Jones, Lyndon; Sheardown, Heather

2015-09-01

This study was designed to assess the impact of a releasable wetting agent, such as hyaluronic acid (HA), on the release profile of timolol maleate (TM) from model silicone hydrogel contact lens materials. Polyvinylpyrrolidone (PVP) was used as an alternative wetting agent for comparison. The model lenses consisted of a hydrophilic monomer, either 2-hydroxyethyl methacrylate or N,N-dimethylacrylamide and a hydrophobic silicone monomer of methacryloxypropyltris (trimethylsiloxy) silane. The loading of the wetting and the therapeutic agent occurred during the synthesis of the silicone hydrogels through the method of direct entrapment. The developed materials were characterized by minimal changes in the water uptake, while lower molecular weight of HA improved their surface wettability. The transparency of the examined silicone hydrogels was found to be affected by the miscibility of the wetting agent in the prepolymer mixture as well as the composition of the developed silicone hydrogels. Sustained release of TM from 4 to 14 days was observed, with the drug transport occurring presumably through the hydrophilic domains of the silicone hydrogels. The release profile was strongly dependent on the hydrophilic monomer composition, the distribution of hydrophobic (silane) domains, and the affinity of the therapeutic agent for the silicone hydrogel matrix. Noncovalent entrapment of the wetting agent did not change the in vitro release duration and kinetics of TM, however the drug release profile was found to be controlled by the simultaneous release of TM and HA or PVP. In the case of HA, depending on the HA:drug ratio, the release rate was decreased and controlled by the release of HA, likely due to electrostatic interactions between protonated TM and anionic HA. Overall, partitioning of the drug within the hydrophilic domains of the silicone hydrogels as well as interactions with the wetting agent determined the drug release profile. © The Author(s) 2015.

Mold and Endotoxin Levels in the Aftermath of Hurricane Katrina: A Pilot Project of Homes in New Orleans Undergoing Renovation

PubMed Central

Chew, Ginger L.; Wilson, Jonathan; Rabito, Felicia A.; Grimsley, Faye; Iqbal, Shahed; Reponen, Tiina; Muilenberg, Michael L.; Thorne, Peter S.; Dearborn, Dorr G.; Morley, Rebecca L.

2006-01-01

Background After Hurricane Katrina, many New Orleans homes remained flooded for weeks, promoting heavy microbial growth. Objectives A small demonstration project was conducted November 2005–January 2006 aiming to recommend safe remediation techniques and safe levels of worker protection, and to characterize airborne mold and endotoxin throughout cleanup. Methods Three houses with floodwater lines between 0.3 and 2 m underwent intervention, including disposal of damaged furnishings and drywall, cleaning surfaces, drying remaining structure, and treatment with a biostatic agent. We measured indoor and outdoor bioaerosols before, during, and after intervention. Samples were analyzed for fungi [culture, spore analysis, polymerase chain reaction (PCR)] and endotoxin. In one house, real-time particle counts were also assessed, and respirator-efficiency testing was performed to establish workplace protection factors (WPF). Results At baseline, culturable mold ranged from 22,000 to 515,000 colony-forming units/m3, spore counts ranged from 82,000 to 630,000 spores/m3, and endotoxin ranged from 17 to 139 endotoxin units/m3. Culture, spore analysis, and PCR indicated that Penicillium, Aspergillus, and Paecilomyces predominated. After intervention, levels of mold and endotoxin were generally lower (sometimes, orders of magnitude). The average WPF against fungal spores for elastomeric respirators was higher than for the N-95 respirators. Conclusions During baseline and intervention, mold and endotoxin levels were similar to those found in agricultural environments. We strongly recommend that those entering, cleaning, and repairing flood-damaged homes wear respirators at least as protective as elastomeric respirators. Recommendations based on this demonstration will benefit those involved in the current cleanup activities and will inform efforts to respond to future disasters. PMID:17185280

Mold and endotoxin levels in the aftermath of Hurricane Katrina: a pilot project of homes in New Orleans undergoing renovation.

PubMed

Chew, Ginger L; Wilson, Jonathan; Rabito, Felicia A; Grimsley, Faye; Iqbal, Shahed; Reponen, Tiina; Muilenberg, Michael L; Thorne, Peter S; Dearborn, Dorr G; Morley, Rebecca L

2006-12-01

After Hurricane Katrina, many New Orleans homes remained flooded for weeks, promoting heavy microbial growth. A small demonstration project was conducted November 2005-January 2006 aiming to recommend safe remediation techniques and safe levels of worker protection, and to characterize airborne mold and endotoxin throughout cleanup. Three houses with floodwater lines between 0.3 and 2 m underwent intervention, including disposal of damaged furnishings and drywall, cleaning surfaces, drying remaining structure, and treatment with a biostatic agent. We measured indoor and outdoor bioaerosols before, during, and after intervention. Samples were analyzed for fungi [culture, spore analysis, polymerase chain reaction (PCR)] and endotoxin. In one house, realtime particle counts were also assessed, and respirator-efficiency testing was performed to establish workplace protection factors (WPF). At baseline, culturable mold ranged from 22,000 to 515,000 colony-forming units/m3, spore counts ranged from 82,000 to 630,000 spores/m3, and endotoxin ranged from 17 to 139 endotoxin units/m3. Culture, spore analysis, and PCR indicated that Penicillium, Aspergillus, and Paecilomyces predominated. After intervention, levels of mold and endotoxin were generally lower (sometimes, orders of magnitude). The average WPF against fungal spores for elastomeric respirators was higher than for the N95 respirators. During baseline and intervention, mold and endotoxin levels were similar to those found in agricultural environments. We strongly recommend that those entering, cleaning, and repairing flood-damaged homes wear respirators at least as protective as elastomeric respirators. Recommendations based on this demonstration will benefit those involved in the current cleanup activities and will inform efforts to respond to future disasters.

Photoactivatable Lipid-based Nanoparticles as a Vehicle for Dual Agent Delivery | NCI Technology Transfer Center | TTC

Cancer.gov

Researchers at the National Cancer Institute (NCI) RNA Biology Laboratory have developed nanoparticles that can deliver an agent (i.e., therapeutic or imaging) and release the agent upon targeted photoactivation allowing for controlled temporal and localized release of the agent.

Fabrication of a Mechanically Robust Carbon Nanofiber Foam

DTIC Science & Technology

2015-06-01

Erlenmeyer exhaust trap utilizing zeolite and permanganate . ........................ 11   Figure 9.   Early CFF experimental mold...containing zeolite and permanganate to dilute the exhaust gases and trap unreacted ethylene prior to their release. Figure 7. MKS mass flow...controller (model MKS 647a). Figure 8. Erlenmeyer exhaust trap utilizing zeolite and permanganate . 12 c. Gas Mixture A flow of pure compressed

Impact of Release Rates on the Effectiveness of Augmentative Biological Control Agents

PubMed Central

Crowder, David W.

2007-01-01

To access the effect of augmentative biological control agents, 31 articles were reviewed that investigated the impact of release rates of 35 augmentative biological control agents on the control of 42 arthropod pests. In 64% of the cases, the release rate of the biological control agent did not significantly affect the density or mortality of the pest insect. Results where similar when parasitoidsor predators were utilized as the natural enemy. Within any order of natural enemy, there were more cases where release rates did not affect augmentative biological control than cases where release rates were significant. There were more cases in which release rates did not affect augmentative biological control when pests were from the orders Hemiptera, Acari, or Diptera, but not with pests from the order Lepidoptera. In most cases, there was an optimal release rate that produced effective control of a pest species. This was especially true when predators were used as a biological control agent. Increasing the release rate above the optimal rate did not improve control of the pest and thus would be economically detrimental. Lower release rates were of ten optimal when biological control was used in conjunction with insecticides. In many cases, the timing and method of biological control applications were more significant factors impacting the effectiveness of biological control than the release rate. Additional factors that may limit the relative impact of release rates include natural enemy fecundity, establishment rates, prey availability, dispersal, and cannibalism. PMID:20307240

Controlled Contamination of Epoxy Composites with PDMS and Removal by Laser Ablation

NASA Technical Reports Server (NTRS)

Palmieri, Frank; Ledesma, Rodolfo; Cataldo, Daniel; Lin, Yi; Wohl, Christopher; Gupta, Mool; Connell, John

2016-01-01

Surface preparation is critical to the performance of adhesively bonded composites. During manufacturing, minute quantities of mold release compounds are inevitably deposited on faying surfaces and may compromise bond performance. To ensure safety, mechanical fasteners and other crack arrest features must be installed in the bondlines of primary structures, which negates some advantages of adhesively bonded construction. Laser ablation is an automated, repeatable, and scalable process with high potential for the surface preparation of metals and composites in critical applications such as primary airframe structures. In this study, laser ablation is evaluated on composite surfaces for the removal of polydimethylsiloxane (PDMS), a common mold release material. Composite panels were contaminated uniformly with PDMS film thicknesses as low as 6.0 nm as measured by variable angle spectroscopic ellipsometry. Bond performance was assessed by mechanical testing using a 250 F cure, epoxy adhesive and compared with pre-bond surface inspection results. Water contact angle, optically stimulated electron emission, and laser induced breakdown spectroscopy were used to characterize contaminated and laser ablated surfaces. The failure mode obtained from double cantilever beam tests correlated well with surface characterization data. The test results indicated that even low levels of PDMS were not completely removed by laser ablation.

The Pursuit of a Scalable Nanofabrication Platform for Use in Material and Life Science Applications

PubMed Central

GRATTON, STEPHANIE E. A.; WILLIAMS, STUART S.; NAPIER, MARY E.; POHLHAUS, PATRICK D.; ZHOU, ZHILIAN; WILES, KENTON B.; MAYNOR, BENJAMIN W.; SHEN, CLIFTON; OLAFSEN, TOVE; SAMULSKI, EDWARD T.; DESIMONE, JOSEPH M.

2008-01-01

CONSPECTUS In this Account, we describe the use of perfluoropolyether (PFPE)-based materials that are able to accurately mold and replicate micro- and nanosized features using traditional techniques such as embossing as well as new techniques that we developed to exploit the exceptional surface characteristics of fluorinated substrates. Because of the unique partial wetting and nonwetting characteristics of PFPEs, we were able to go beyond the usual molding and imprint lithography approaches and have created a technique called PRINT (Particle [or Pattern] Replication In Nonwetting Templates). PRINT is a distinctive “top-down” fabrication technique capable of generating isolated particles, arrays of particles, and arrays of patterned features for a plethora of applications in both nanomedicine and materials science. A particular strength of the PRINT technology is the high-resolution molding of well-defined particles with precise control over size, shape, deformability, and surface chemistry. The level of replication obtained showcases some of the unique characteristics of PFPE molding materials. In particular, these materials arise from very low surface energy precursors with positive spreading coefficients, can be photocured at ambient temperature, and are minimally adhesive, nonswelling, and conformable. These distinctive features enable the molding of materials with unique attributes and nanometer resolution that have unprecedented scientific and technological value. For example, in nanomedicine, the use of PFPE materials with the PRINT technique allows us to design particles in which we can tailor key therapeutic parameters such as bioavailability, biodistribution, target-specific cell penetration, and controlled cargo release. Similarly, in materials science, we can fabricate optical films and lens arrays, replicate complex, naturally occurring objects such as adenovirus particles, and create 2D patterned arrays of inorganic oxides. PMID:18720952

Development and characterization of a dynamic lesion phantom for the quantitative evaluation of dynamic contrast-enhanced MRI

PubMed Central

Freed, Melanie; de Zwart, Jacco A.; Hariharan, Prasanna; R. Myers, Matthew; Badano, Aldo

2011-01-01

Purpose: To develop a dynamic lesion phantom that is capable of producing physiological kinetic curves representative of those seen in human dynamic contrast-enhanced MRI (DCE-MRI) data. The objective of this phantom is to provide a platform for the quantitative comparison of DCE-MRI protocols to aid in the standardization and optimization of breast DCE-MRI. Methods: The dynamic lesion consists of a hollow, plastic mold with inlet and outlet tubes to allow flow of a contrast agent solution through the lesion over time. Border shape of the lesion can be controlled using the lesion mold production method. The configuration of the inlet and outlet tubes was determined using fluid transfer simulations. The total fluid flow rate was determined using x-ray images of the lesion for four different flow rates (0.25, 0.5, 1.0, and 1.5 ml∕s) to evaluate the resultant kinetic curve shape and homogeneity of the contrast agent distribution in the dynamic lesion. High spatial and temporal resolution x-ray measurements were used to estimate the true kinetic curve behavior in the dynamic lesion for benign and malignant example curves. DCE-MRI example data were acquired of the dynamic phantom using a clinical protocol. Results: The optimal inlet and outlet tube configuration for the lesion molds was two inlet molds separated by 30° and a single outlet tube directly between the two inlet tubes. X-ray measurements indicated that 1.0 ml∕s was an appropriate total fluid flow rate and provided truth for comparison with MRI data of kinetic curves representative of benign and malignant lesions. DCE-MRI data demonstrated the ability of the phantom to produce realistic kinetic curves. Conclusions: The authors have constructed a dynamic lesion phantom, demonstrated its ability to produce physiological kinetic curves, and provided estimations of its true kinetic curve behavior. This lesion phantom provides a tool for the quantitative evaluation of DCE-MRI protocols, which may lead to improved discrimination of breast cancer lesions. PMID:21992378

[Influence of titanium dioxide activated under visible light on survival of mold fungi].

PubMed

Kądziołka, Daria; Rokicka, Paulina; Markowska-Szczupak, Agata; Morawski, Antoni W

2018-01-01

In public and residential buildings, fungi are usually found in the dust or growing on building materials medium such. It has been known that a number of their spores may contaminate the indoor environment and deteriorate air quality in accommodation spaces. Previously designed air cleaning systems do not guarantee a complete removal of agents harmful to humans and animals. Therefore, there is a great need to develop a new solution to remove molds from indoor air. In recent years, photocatalysis based on titanium dioxide (TiO₂) has been proposed as an effective method for air pollutants removal. The aim of the study was to determine the effect of TiO₂ activated under artificial sun light (UV-VIS - ultraviolet - visible spectroscopy) on survival of fungi Penicillium chrysogenum and Aspergillus niger. The commercial P 25 (Aeroxide P 25, Evonik, Germany) and nitrogen modified titanium dioxide (N-TiO₂) were used. The microbiological study was performed using Penicillium chrysogenum and Aspergillus niger fungi. The survival of fungi was determined on the basis of changes in their concentration. It was found that N-TiO₂ has a stronger antifungal activity against P. chrysogenum and A. niger than P 25. For N-TiO2, the complete elimination of molds was possible after 3 h under artificial solar light activation. The minimal concentration of photocatalyst was 0.01 g×dm^-3 (P. chrysogenum) and 0.1 g×dm^-3 (A. niger). The nitrogen modification of titanium dioxide produced expected results and N-TiO₂ presented good antifungal activity. The findings of the presented investigation can lead to the development of air filter to be used for removal of harmful agents (including molds) from indoor environment. Med Pr 2018;69(1):59-65. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Antifungal susceptibilities of Candida, Cryptococcus neoformans and Aspergillus fumigatus from the Asia and Western Pacific region: data from the SENTRY antifungal surveillance program (2010-2012).

PubMed

Pfaller, Michael A; Messer, Shawn A; Jones, Ronald N; Castanheira, Mariana

2015-09-01

The SENTRY Antifungal Surveillance Program monitors global susceptibility rates of newer and established antifungal agents. We report the in vitro activity of seven antifungal agents against 496 contemporary clinical isolates of yeasts and molds. The isolates were obtained from 20 laboratories in the Asia-Western Pacific (APAC) region during 2010 through 2012. Anidulafungin, caspofungin, micafungin, fluconazole, itraconazole, posaconazole and voriconazole were susceptibility tested using CLSI methods and species-specific interpretive criteria. Sequencing of fks hot spots was performed for echinocandin-resistant strains. Isolates included 13 species of Candida (n=460), 5 species of non-Candida yeasts (21), 5 species of Aspergillus (11) and 4 other molds. Echinocandin resistance was uncommon among eight species of Candida and was only detected in three isolates of Candida glabrata, two from Australia harboring mutations in fks1 (F625S) and fks2 (S663P). Resistance to the azoles was much more common and was observed among all species with the exception of Candida dubliniensis. Fluconazole resistance rates observed with C. glabrata (6.8%) was comparable to that seen with Candida parapsilosis (5.7%) and Candida tropicalis (3.6%). Cross resistance among the triazoles was seen with each of these three species. The mold-active azoles and the echinocandins were all active against isolates of Aspergillus fumigatus. Azole resistance was not detected among the isolates of Cryptococcus neoformans. Antifungal resistance is uncommon among isolates of fungi causing invasive fungal infections in the APAC region. As in other regions of the world, emerging resistance to the echinocandins among invasive isolates of C. glabrata bears close monitoring.

Injectable Biodegradable Polyurethane Scaffolds with Release of Platelet-derived Growth Factor for Tissue Repair and Regeneration

PubMed Central

Hafeman, Andrea E.; Li, Bing; Yoshii, Toshitaka; Zienkiewicz, Katarzyna; Davidson, Jeffrey M.; Guelcher, Scott A.

2013-01-01

Purpose The purpose of this work was to investigate the effects of triisocyanate composition on the biological and mechanical properties of biodegradable, injectable polyurethane scaffolds for bone and soft tissue engineering. Methods Scaffolds were synthesized using reactive liquid molding techniques, and were characterized in vivo in a rat subcutaneous model. Porosity, dynamic mechanical properties, degradation rate, and release of growth factors were also measured. Results Polyurethane scaffolds were elastomers with tunable damping properties and degradation rates, and they supported cellular infiltration and generation of new tissue. The scaffolds showed a two-stage release profile of platelet-derived growth factor, characterized by a 75% burst release within the first 24 h and slower release thereafter. Conclusions Biodegradable polyurethanes synthesized from triisocyanates exhibited tunable and superior mechanical properties compared to materials synthesized from lysine diisocyanates. Due to their injectability, biocompatibility, tunable degradation, and potential for release of growth factors, these materials are potentially promising therapies for tissue engineering. PMID:18516665

Bubble Jet agent release cartridge for chemical single cell stimulation.

PubMed

Wangler, N; Welsche, M; Blazek, M; Blessing, M; Vervliet-Scheebaum, M; Reski, R; Müller, C; Reinecke, H; Steigert, J; Roth, G; Zengerle, R; Paust, N

2013-02-01

We present a new method for the distinct specific chemical stimulation of single cells and small cell clusters within their natural environment. By single-drop release of chemical agents with droplets in size of typical cell diameters (d <30 μm) on-demand micro gradients can be generated for the specific manipulation of single cells. A single channel and a double channel agent release cartridge with integrated fluidic structures and integrated agent reservoirs are shown, tested, and compared in this publication. The single channel setup features a fluidic structure fabricated by anisotropic etching of silicon. To allow for simultaneous release of different agents even though maintaining the same device size, the second type comprises a double channel fluidic structure, fabricated by photolithographic patterning of TMMF. Dispensed droplet volumes are V = 15 pl and V = 10 pl for the silicon and the TMMF based setups, respectively. Utilizing the agent release cartridges, the application in biological assays was demonstrated by hormone-stimulated premature bud formation in Physcomitrella patens and the individual staining of one single L 929 cell within a confluent grown cell culture.

A modified SILCS contraceptive diaphragm for long-term controlled release of the HIV microbicide dapivirine.

PubMed

Major, Ian; Boyd, Peter; Kilbourne-Brook, Maggie; Saxon, Gene; Cohen, Jessica; Malcolm, R Karl

2013-07-01

There is considerable interest in developing new multipurpose prevention technologies to address women's reproductive health needs. This study describes an innovative barrier contraceptive device--based on the SILCS diaphragm--that also provides long-term controlled release of the lead candidate anti-HIV microbicide dapivirine. Diaphragm devices comprising various dapivirine-loaded polymer spring cores overmolded with a nonmedicated silicone elastomer sheath were fabricated by injection molding processes. In vitro release testing, thermal analysis and mechanical characterization were performed on the devices. A diaphragm device containing a polyoxymethylene spring core loaded with 10% w/w dapivirine provided continuous and controlled release of dapivirine over a 6-month period, with a mean in vitro daily release rate of 174 mcg/day. The mechanical properties of the new diaphragm were closely matched to the SILCS diaphragm. The study demonstrates proof of concept for a dapivirine-releasing diaphragm with daily release quantities potentially capable of preventing HIV transmission. In discontinuous clinical use, release of dapivirine may be readily extended over 1 or more years. Copyright © 2013 Elsevier Inc. All rights reserved.

42 CFR 412.616 - Release of information collected using the patient assessment instrument.

Code of Federal Regulations, 2010 CFR

2010-10-01

....24(b)(3) of this chapter. (b) Release to the inpatient rehabilitation facility's agent. An inpatient rehabilitation facility may release information that is patient-identifiable to an agent only in accordance with... 42 Public Health 2 2010-10-01 2010-10-01 false Release of information collected using the patient...

Population dynamics and impacts of the red-headed leafy spurge stem borer on leafy spurge (Euphorbia esula)

Treesearch

Robert A. Progar; George Markin; Joseph Milan; Tom Barbouletos; Matthew J. Rinella

2011-01-01

We evaluated the efficacy of the biological control agent, red-headed leafy spurge stem borer, against the nonnative invasive plant leafy spurge. Our three treatments were release of the biological control agent into uncaged plots, release of the biological control agent into plots caged to prevent agent escape, and control plots caged to prevent agent entry. These...

Antimicrobial Properties of Natural Phenols and Related Compounds

PubMed Central

Jurd, L.; King, A. D.; Mihara, K.; Stanley, W. L.

1971-01-01

Obtusastyrene (4-cinnamylphenol) displays effective antimicrobial activity in vitro against a variety of gram-positive bacteria, yeasts, and molds. The activity of obtusastyrene is not appreciably affected by pH, and its minimal inhibitory concentrations, 12 to 25 μg/ml for bacteria and 12 to 100 μg/ml for fungi, compare favorably with those of a number of synthetic, phenolic antimicrobial agents. PMID:5553287

Blastomyces dermatitidis septins CDC3, CDC10, and CDC12 impact the morphology of yeast and hyphae, but are not required for the phase transition.

PubMed

Marty, Amber J; Gauthier, Gregory M

2013-01-01

Blastomyces dermatitidis, the etiologic agent of blastomycosis, belongs to a group of thermally dimorphic fungi that change between mold (22°C) and yeast (37°C) in response to temperature. The contribution of structural proteins such as septins to this phase transition in these fungi remains poorly understood. Septins are GTPases that serve as a scaffold for proteins involved with cytokinesis, cell polarity, and cell morphology. In this study, we use a GFP sentinel RNA interference system to investigate the impact of CDC3, CDC10, CDC12, and ASPE on the morphology and phase transition of B. dermatitidis. Targeting CDC3, CDC10, and CDC12 by RNA interference resulted in yeast with aberrant morphology at 37°C with defects in cytokinesis. Downshifting the temperature to 22°C promoted the conversion to the mold phase, but did not abrogate the morphologic defects. CDC3, CDC10, and CDC12 knockdown strains grew as mold with curved, thickened hyphae. Knocking down ASPE transcript did not alter morphology of yeast at 37°C or mold at 22°C. Following an increase in temperature from 22°C to 37°C, all septin knockdown strains were able to revert to yeast. In conclusion, CDC3, CDC10, and CDC12 septin- encoding genes are required for proper morphology of yeast and hyphae, but are dispensable for the phase transition.

Foam injection molding of elastomers with iron microparticles

NASA Astrophysics Data System (ADS)

Volpe, Valentina; D'Auria, Marco; Sorrentino, Luigi; Davino, Daniele; Pantani, Roberto

2015-12-01

In this work, a preliminary study of foam injection molding of a thermoplastic elastomer, Engage 8445, and its microcomposite loaded with iron particles was carried out, in order to evaluate the effect of the iron microparticles on the foaming process. In particular, reinforced samples have been prepared by using nanoparticles at 2% by volume. Nitrogen has been used as physical blowing agent. Foamed specimens consisting of neat and filled elastomer were characterized by density measurements and morphological analysis. While neat Engage has shown a well developed cellular morphology far from the injection point, the addition of iron microparticles considerably increased the homogeneity of the cellular morphology. Engage/iron foamed samples exhibited a reduction in density greater than 32%, with a good and homogeneous cellular morphology, both in the transition and in the core zones, starting from small distances from the injection point.

Release time of residual oxygen after dental bleaching with 35% hydrogen peroxide: effect of a catalase-based neutralizing agent.

PubMed

Guasso, Bárbara; Salomone, Paloma; Nascimento, Paulo Cícero; Pozzobon, Roselaine Terezinha

2016-01-01

This article assessed the effect of a catalase-based agent on residual oxygen (O2) release from teeth exposed to 35% hydrogen peroxide (H2O2). The use of the catalase-based neutralizer agent for 2-3 minutes was able to release residual O2 5 days after exposure to a 35% H2O2-based bleaching gel.

Effect of Silane Coupling Agent on Tribological Properties of Hemp Fiber-Reinforced Plant-Derived Polyamide 1010 Biomass Composites

PubMed Central

Kajiyama, Tetsuto; Yamanaka, Toshiyuki

2017-01-01

We have studied the effects of silane coupling agents used for the surface treatment of fiber on the tribological properties of hemp fiber (HF) reinforced plant-derived polyamide 1010 (PA1010) biomass composites. Hemp fibers were surface-treated by two surface treatment methods: (a) alkali treatment by sodium hydroxide solution and (b) surface treatment by silane coupling agents. Three types of silane coupling agents, namely aminosilane, epoxysilane and ureidosilane were used. These HF/PA1010 biomass composites were extruded using a twin extruder, and injection-molded. The mechanical and tribological properties were evaluated by the ring-on-plate type sliding wear test. It was found that tribological properties of HF/PA1010 biomass composites improved with the surface treatment by the silane coupling agent. This may be attributed to the change in the mode of friction and wear mechanism by the interfacial adhesion between fiber and matrix polymer according to the type of silane coupling agent used. In particular, the ureidosilane coupling agent showed the best improvement effect for the tribological properties of these biomass composites in this study. PMID:28872624

Noninvasive visualization of in vivo release and intratumoral distribution of surrogate MR contrast agent using the dual MR contrast technique.

PubMed

Onuki, Yoshinori; Jacobs, Igor; Artemov, Dmitri; Kato, Yoshinori

2010-09-01

A direct evaluation of the in vivo release profile of drugs from carriers is a clinical demand in drug delivery systems, because drug release characterized in vitro correlates poorly with in vivo release. The purpose of this study is to demonstrate the in vivo applicability of the dual MR contrast technique as a useful tool for noninvasive monitoring of the stability and the release profile of drug carriers, by visualizing in vivo release of the encapsulated surrogate MR contrast agent from carriers and its subsequent intratumoral distribution profile. The important aspect of this technique is that it incorporates both positive and negative contrast agents within a single carrier. GdDTPA, superparamagnetic iron oxide nanoparticles, and 5-fluorouracil were encapsulated in nano- and microspheres composed of poly(D,L-lactide-co-glycolide), which was used as a model carrier. In vivo studies were performed with orthotopic xenograft of human breast cancer. The MR-based technique demonstrated here has enabled visualization of the delivery of carriers, and release and intratumoral distribution of the encapsulated positive contrast agent. This study demonstrated proof-of-principle results for the noninvasive monitoring of in vivo release and distribution profiles of MR contrast agents, and thus, this technique will make a great contribution to the field. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Evaluation of proposed Skylab and SSP soap products.

NASA Technical Reports Server (NTRS)

Durfee, R. L.; Spurlock, J. M.; Whitmore, F. C.

1973-01-01

Four candidate cleansing agents evaluated in terms of potential hazards to crew members included two soaps (Neutrogena bar soap and Olive Leaf Liquid), one nonfoaming surfactant (Miranol JEM), and one laundry detergent (sodium dodecylbenzene sulfonate). None of the four exhibited adverse dermatological effects from skin patch tests or supported growth of potentially pathogenic microorganisms. Aqueous solutions of Neutrogena did support a mold species. Neutrogena and Miranol JEM were used in a simulated Skylab personal hygiene regimen with no adverse effects on skin or skin microflora. Based on our results, each of these agents appear to be a promising candidate material for the use intended.

Controlled release of metronidazole from composite poly-ε-caprolactone/alginate (PCL/alginate) rings for dental implants.

PubMed

Lan, Shih-Feng; Kehinde, Timilehin; Zhang, Xiangming; Khajotia, Sharukh; Schmidtke, David W; Starly, Binil

2013-06-01

Dental implants provide support for dental crowns and bridges by serving as abutments for the replacement of missing teeth. To prevent bacterial accumulation and growth at the site of implantation, solutions such as systemic antibiotics and localized delivery of bactericidal agents are often employed. The objective of this study was to demonstrate a novel method of controlled localized delivery of antibacterial agents to an implant site using a biodegradable custom fabricated ring. The study involved incorporating a model antibacterial agent (metronidazole) into custom designed poly-ε-caprolactone/alginate (PCL/alginate) composite rings to produce the intended controlled release profile. The rings can be designed to fit around the body of any root form dental implants of various diameters, shapes and sizes. In vitro release studies indicate that pure (100%) alginate rings exhibited an expected burst release of metronidazole in the first few hours, whereas Alginate/PCL composite rings produced a medium burst release followed by a sustained release for a period greater than 4 weeks. By varying the PCL/alginate weight ratios, we have shown that we can control the amount of antibacterial agents released to provide the minimal inhibitory concentration (MIC) needed for adequate protection. The fabricated composite rings have achieved a 50% antibacterial agent release profile over the first 48 h and the remaining amount slowly released over the remainder of the study period. The PCL/alginate agent release characteristic fits the Ritger-Peppas model indicating a diffusion-based mechanism during the 30-day study period. The developed system demonstrates a controllable drug release profile and the potential for the ring to inhibit bacterial biofilm growth for the prevention of diseases such as peri-implantitis resulting from bacterial infection at the implant site. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Coaxial electrospinning for encapsulation and controlled release of fragile water-soluble bioactive agents.

PubMed

Jiang, Hongliang; Wang, Liqun; Zhu, Kangjie

2014-11-10

Coaxial electrospinning is a robust technique for one-step encapsulation of fragile, water-soluble bioactive agents, including growth factors, DNA and even living organisms, into core-shell nanofibers. The coaxial electrospinning process eliminates the damaging effects due to direct contact of the agents with organic solvents or harsh conditions during emulsification. The shell layer serves as a barrier to prevent the premature release of the water-soluble core contents. By varying the structure and composition of the nanofibers, it is possible to precisely modulate the release of the encapsulated agents. Promising work has been done with coaxially electrospun non-woven mats integrated with bioactive agents for use in tissue engineering, in local delivery and in wound healing, etc. This paper reviews the origins of the coaxial electrospinning method, its updated status and potential future developments for controlled release of the class of fragile, water-soluble bioactive agents. Copyright © 2014 Elsevier B.V. All rights reserved.

Optimization of chlorphenesin emulgel formulation.

PubMed

Mohamed, Magdy I

2004-10-11

This study was conducted to develop an emulgel formulation of chlorphenesin (CHL) using 2 types of gelling agents: hydroxypropylmethyl cellulose (HPMC) and Carbopol 934. The influence of the type of the gelling agent and the concentration of both the oil phase and emulsifying agent on the drug release from the prepared emulgels was investigated using a 2(3) factorial design. The prepared emulgels were evaluated for their physical appearance, rheological behavior, drug release, antifungal activity, and stability. Commercially available CHL topical powder was used for comparison. All the prepared emulgels showed acceptable physical properties concerning color, homogeneity, consistency, spreadability, and pH value. They also exhibited higher drug release and antifungal activity than the CHL powder. It was found that the emulsifying agent concentration had the most pronounced effect on the drug release from the emulgels followed by the oil phase concentration and finally the type of the gelling agent. The drug release from all the emulgels was found to follow diffusion-controlled mechanism. Rheological studies revealed that the CHL emulgels exhibited a shear-thinning behavior with thixotropy. Stability studies showed that the physical appearance, rheological properties, drug release, and antifungal activity in all the prepared emulgels remained unchanged upon storage for 3 months. As a general conclusion, it was suggested that the CHL emulgel formulation prepared with HPMC with the oil phase concentration in its low level and emulsifying agent concentration in its high level was the formula of choice since it showed the highest drug release and antifungal activity.

Population dynamics and impacts of the red-headed leafy spurge stem borer on leafy spurge

Treesearch

R. A. Progar; G. P. Markin; J. Milan; T. Barbouletos; M. J. Rinella

2013-01-01

We evaluated the efficacy of the biological control agent, red-headed leafy spurge stem borer (Oberea erythrocephala Schrank.) against the nonnative invasive plant leafy spurge (Euphorbia esula L.). Our three treatments were release of the biological control agent into uncaged plots, release of the biological control agent into plots caged to prevent agent escape and...

Long-term field evaluation of Mecinus janthinus releases against Dalmatian toadflax in Montana (USA)

Treesearch

Sharlene Sing; D. K. Weaver; R. M. Nowierski; G. P. Markin

2008-01-01

The toadflax stem mining weevil, Mecinus janthinus Germar, was first released in the United States in Montana, in 1996. This agent has now become established to varying degrees after subsequent releases made at sites throughout the state. Multiple releases of M. janthinus have presented researchers with a unique opportunity to evaluate the efficacy of this agent in...

Volatile organic compounds as markers of quality changes during the storage of wild rocket.

PubMed

Luca, Alexandru; Kjær, Anders; Edelenbos, Merete

2017-10-01

The quality of leafy green vegetables changes during storage. Leaves become yellow or disintegrate, and an off-odor may develop. In addition, small amounts of volatile organic compounds (VOCs) are released. In this study, the release of acetone, carbon disulfide, dimethyl sulfide, nitromethane, pentane, 3-methylfuran, 2-ethylfuran, and dimethyl disulfide from wild rocket with different initial qualities was monitored during 8d storage at 10°C and correlated to aerobic bacteria counts, yeast and mold counts, and degree of tissue disintegration. The release of VOCs, except for 3-methylfuran, was influenced by the initial quality of the leaves. The release of pentane and 2-ethylfuran was related to the degree of tissue disintegration, and the release of dimethyl sulfide and dimethyl disulfide was related to the total aerobic bacteria count. The results demonstrated that VOCs can be used as markers for monitoring the complex quality changes taking place in packaged fresh produce during storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

The ability of a cold-adapted Rhodotorula mucilaginosa strain from Tibet to control blue mold in pear fruit.

PubMed

Hu, Hao; Yan, Fujie; Wilson, Charles; Shen, Qing; Zheng, Xiaodong

2015-12-01

Cold-adapted yeasts were isolated from soil samples collected in Tibet and evaluated as potential biocontrol agents against blue mold (Penicillium expansum) of pear fruit in cold storage. YC1, an isolate identified as Rhodotorula mucilaginosa, was found to exhibit the greatest biocontrol activity among the different isolates that were screened. A washed cell suspension of YC1 exhibited the best biocontrol activity among three different preparations that were used in the current study. A concentration of 10(8) cells/ml reduced the incidence of decay to 35 %, compared to the control where decay incidence was 100 %. A higher intracellular level of trehalose and a higher proportion of polyunsaturated acids present in YC1, was associated with increased the tolerance of this strain to low temperatures, relative to the other strains that were evaluated. The increased tolerance to low temperature allowed the YC1 strain of yeast to more effectively compete for nutrients and space in wounded pear fruit that had been inoculated with spores of P. expansum and placed in cold storage. The present study demonstrated the ability to select cold-adapted yeasts from cold climates and use them as biocontrol agents of postharvest diseases of fruit placed in cold storage.

A stimuli responsive liposome loaded hydrogel provides flexible on-demand release of therapeutic agents.

PubMed

O'Neill, Hugh S; Herron, Caroline C; Hastings, Conn L; Deckers, Roel; Lopez Noriega, Adolfo; Kelly, Helena M; Hennink, Wim E; McDonnell, Ciarán O; O'Brien, Fergal J; Ruiz-Hernández, Eduardo; Duffy, Garry P

2017-01-15

Lysolipid-based thermosensitive liposomes (LTSL) embedded in a chitosan-based thermoresponsive hydrogel matrix (denoted Lipogel) represents a novel approach for the spatiotemporal release of therapeutic agents. The entrapment of drug-loaded liposomes in an injectable hydrogel permits local liposome retention, thus providing a prolonged release in target tissues. Moreover, release can be controlled through the use of a minimally invasive external hyperthermic stimulus. Temporal control of release is particularly important for complex multi-step physiological processes, such as angiogenesis, in which different signals are required at different times in order to produce a robust vasculature. In the present work, we demonstrate the ability of Lipogel to provide a flexible, easily modifiable release platform. It is possible to tune the release kinetics of different drugs providing a passive release of one therapeutic agent loaded within the gel and activating the release of a second LTSL encapsulated agent via a hyperthermic stimulus. In addition, it was possible to modify the drug dosage within Lipogel by varying the duration of hyperthermia. This can allow for adaption of drug dosing in real time. As an in vitro proof of concept with this system, we investigated Lipogels ability to recruit stem cells and then elevate their production of vascular endothelial growth factor (VEGF) by controlling the release of a pro-angiogenic drug, desferroxamine (DFO) with an external hyperthermic stimulus. Initial cell recruitment was accomplished by the passive release of hepatocyte growth factor (HGF) from the hydrogel, inducing a migratory response in cells, followed by the delayed release of DFO from thermosensitive liposomes, resulting in a significant increase in VEGF expression. This delayed release could be controlled up to 14days. Moreover, by changing the duration of the hyperthermic pulse, a fine control over the amount of DFO released was achieved. The ability to trigger the release of therapeutic agents at a specific timepoint and control dosing level through changes in duration of hyperthermia enables sequential multi-dose profiles. This paper details the development of a heat responsive liposome loaded hydrogel for the controlled release of pro-angiogenic therapeutics. Lysolipid-based thermosensitive liposomes (LTSLs) embedded in a chitosan-based thermoresponsive hydrogel matrix represents a novel approach for the spatiotemporal release of therapeutic agents. This hydrogel platform demonstrates remarkable flexibility in terms of drug scheduling and sequencing, enabling the release of multiple agents and the ability to control drug dosing in a minimally invasive fashion. The possibility to tune the release kinetics of different drugs independently represents an innovative platform to utilise for a variety of treatments. This approach allows a significant degree of flexibility in achieving a desired release profile via a minimally invasive stimulus, enabling treatments to be tuned in response to changing symptoms and complications. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

46 CFR 185.612 - Fire protection equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... releasing the extinguishing agent should the local manual release or stop valve controls fail to operate... at or near each pull box and stop valve control and in the space where the extinguishing agent...-VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED”. Where a different extinguishing agent is installed, that...

45 CFR 35.8 - Release.

Code of Federal Regulations, 2010 CFR

2010-10-01

... § 35.8 Release. Acceptance by the claimant, his agent or legal representative, of any award, compromise or settlement made hereunder, shall be final and conclusive on the claimant, his agent or legal... 45 Public Welfare 1 2010-10-01 2010-10-01 false Release. 35.8 Section 35.8 Public Welfare...

40 CFR 10.8 - Release.

Code of Federal Regulations, 2010 CFR

2010-07-01

... CLAIMS ACT Procedures § 10.8 Release. Acceptance by the claimant, his agent or legal representative of... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Release. 10.8 Section 10.8 Protection... agent or legal representative and any other person on whose behalf or for whose benefit the claim has...

Comparison of the ActiDes-Blue and CARELA HYDRO-DES technology for the sanitation of contaminated cooling water systems in dental units.

PubMed

Kramer, Axel; Lemanski, Sandra; Demond, Kathleen; Assadian, Ojan

2012-01-01

The hygienic-microbiological control of 6 dental units being in use for the past 16 years revealed a significantly increased microbial contamination of their cooling water system. In order to comply with the requirements of the drinking water directive ("Trinkwasserverordnung"), the commercially available production system ActiDes, producing on-site ActiDes-Blue which is based on hypochlorous acid (HOCl) and generated by anodic oxidation, was investigated. Water samples from the 6 contaminated dental units were examined for the total number of colony forming units (cfu), contamination with molds, L. pneumophila and P. aeruginosa. The control period for the total colony count was 4 weeks (8 samples/unit). The subsequent application phase of the ActiDes-Blue procedure was 6 months (31 samples/unit). Additionally, the redox potential and the pH value were measured.Futhermore, the decontamination agent CARELA HYDRO-DES, a two component agent based on H(2)O(2) with the addition of a mixture of sodium hydrogen sulphate and sulphuric acid in an aqueous solution effective at 0.1% and higher, was applied in a unit that had been put out of service for a month before. Before application, the system was first filled with a 5% solution of the alkaline pre-cleaning agent CARELA Solvent for bacterial slime; the system was left with this solution for 1 h. The pre-cleaning agent was then completely displaced from the system with tap water and a decontaminating solution of 5% CARELA HYDRO-DES and left in place for 1 h. Drinking water quality level was reached only twice during the control phase. The average values of the dental units ranged between 3,633 CFU/ml and 29,417 c/ml. During the application phase, drinking water level could be achieved in 11 water samples. In another 6 water samples a total colony count of <150 cfu/ml was reached. The average values for the dental units' total colony count ranged between 529 cfu/ml and 87,450 cfu/ml. No significant differences between the control phase and the action phase could be demonstrated. During the control phase, contamination of the water samples with a mold was noticed so that examinations for molds were carried out beyond the scope of the drinking water directive. For this parameter as well, no significant differences between the phases of the study could be shown.The Legionella load of the dental units was low. L. pneumophila were yielded in only 4 out of 130 water samples. During the control phase, twice colony counts at 50 cfu/1,000 ml and 110 cfu/1,000 ml were measured. During the action phase, counts with Legionella spp. could be measured at 5 cfu/1,000 ml for one unit only. Also, with 1-10 cfu/100 ml, the P. aeruginosa contamination was low. During the application phase, it ranged between 0-7 cfu/100 ml.Redox potential and pH value showed a slight decrease during the application phase.Before treatment with CARELA Solvent and CARELA HYDRO-DES, the initial contamination of the total count of bacterial colonies was 1,432 cfu/ml at 22°C and 846 cfu/ml at 36°C as well as >1,000 cfu/100 ml for molds. 1 h after the decontamination, no bacteria and molds could be detected in 1,000 ml of tap water. Despite the fact that the unit was not used any longer, after 7 d the bacterial colony count was 3 cfu/ml at 22°C and 2 cfu/ml at 36°C while molds could not be detected. Even after a rest time of 14 d only 167 cfu/ml or 42 cfu/ml could be yielded. Molds were further not cultivable. A material damage could not be observed. Pertaining to the ActiDes technology's effectiveness, it has to be pointed out that the dental units investigated were those used for dental students' teaching and therefore were clearly less frequently used than clinically used units in a dental practice. This resulted in distinctly longer stagnation periods which favored formation of biofilms. In summary, the ActiDes technology and ActiDes-Blue showed not to be sufficiently effective for the sanitation of contaminated water reservoirs in dental units under aggravated conditions of repeated and longer periods of non-use in connection with longer water stagnation periods. In comparison, the biofilm was sustainably eliminated through the combined application of CARELA(®) Solvent for Bacterial Slime with subsequent decontamination using CARELA(®) HYDRO-DES.

"Effect of nano-filled surface coating agent on fluoride release from conventional glass ionomer cement: an in vitro trial".

PubMed

Tiwari, S; Nandlal, B

2013-01-01

To overcome the drawbacks of glass ionomer cement of sensitivity to initial desiccation and moisture contamination the use of surface coating agent is recommended. The search in this area led to invent of use of nanofillers in surface coating agent, but its effect on fluoride release is not clear. The aim of this study is to evaluate and compare the fluoride release from conventional glass ionomer cement with and without surface coating agent. This in vitro study comprised of total 80 samples (40 samples of each with and without surface coating). Specimens were prepared, G coat plus was applied and light cured. Fluoride release of the sample was measured every 24 h for 7 days and weekly from 7th to 21 st day using Sension4 pH/ISE/MV Meter. Descriptive Statistics, Repeated Measure ANOVA, Paired Sample t-test, Independent Sample t-test, Scheffe post hoc test. Mean values clearly reveal a significant decrease in the fluoride release from day 1 to day 21 for both groups. Non-coated group released significantly more fluoride than surface coated group (P<0.001). It can be concluded that nanofilled surface coating agent will reduce the amount of fluoride released into oral environment as compared to non-coated group and at the same time releasing fluoride into surrounding cavity walls to create zones of inhibition into the cavity floor to help internal remineralization.

The Development of High Temperature Thermoplastic Composite Materials for Additive Manufactured Autoclave Tooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kunc, Vlastimil; Duty, Chad E.; Lindahl, John M.

2017-08-01

In this work, ORNL and Techmer investigated and screened different high temperature thermoplastic reinforced materials to fabricate composite molds for autoclave processes using Additive Manufacturing (AM) techniques. This project directly led to the development and commercial release of two printable, high temperature composite materials available through Techmer PM. These new materials are targeted for high temperature tooling made via large scale additive manufacturing.

Fabrication of balloon-expandable self-lock drug-eluting polycaprolactone stents using micro-injection molding and spray coating techniques.

PubMed

Liu, Shih-Jung; Chiang, Fu-Jun; Hsiao, Chao-Ying; Kau, Yi-Chuan; Liu, Kuo-Sheng

2010-10-01

The purpose of this report was to develop novel balloon-expandable self-lock drug-eluting poly(ε-caprolactone) stents. To fabricate the biodegradable stents, polycaprolactone (PCL) components were first fabricated by a lab-scale micro-injection molded machine. They were then assembled and hot-spot welded into mesh-like stents of 3 and 5 mm in diameters. A special geometry of the components was designed to self-lock the assembled stents and to resist the external pressure of the blood vessels after being expanded by balloons. Characterization of the biodegradable PCL stents was carried out. PCL stents exhibited comparable mechanical property to that of metallic stents. No significant collapse pressure reduction and weight loss of the stents were observed after being submerged in PBS for 12 weeks. In addition, the developed stent was coated with paclitaxel by a spray coating technique and the release characteristic of the drug was determined by an in vitro elution method. The high-performance liquid chromatography analysis showed that the biodegradable stents could release a high concentration of paclitaxel for more than 60 days. By adopting the novel techniques, we will be able to fabricate biodegradable drug-eluting PCL stents of different sizes for various cardiovascular applications.

Shrink-induced superhydrophobic and antibacterial surfaces in consumer plastics.

PubMed

Freschauf, Lauren R; McLane, Jolie; Sharma, Himanshu; Khine, Michelle

2012-01-01

Structurally modified superhydrophobic surfaces have become particularly desirable as stable antibacterial surfaces. Because their self-cleaning and water resistant properties prohibit bacteria growth, structurally modified superhydrophobic surfaces obviate bacterial resistance common with chemical agents, and therefore a robust and stable means to prevent bacteria growth is possible. In this study, we present a rapid fabrication method for creating such superhydrophobic surfaces in consumer hard plastic materials with resulting antibacterial effects. To replace complex fabrication materials and techniques, the initial mold is made with commodity shrink-wrap film and is compatible with large plastic roll-to-roll manufacturing and scale-up techniques. This method involves a purely structural modification free of chemical additives leading to its inherent consistency over time and successive recasting from the same molds. Finally, antibacterial properties are demonstrated in polystyrene (PS), polycarbonate (PC), and polyethylene (PE) by demonstrating the prevention of gram-negative Escherichia coli (E. coli) bacteria growth on our structured plastic surfaces.

Melt-processed polymeric cellular dosage forms for immediate drug release.

PubMed

Blaesi, Aron H; Saka, Nannaji

2015-12-28

The present immediate-release solid dosage forms, such as the oral tablets and capsules, comprise granular matrices. While effective in releasing the drug rapidly, they are fraught with difficulties inherent in processing particulate matter. By contrast, liquid-based processes would be far more predictable; but the standard cast microstructures are unsuited for immediate-release because they resist fluid percolation and penetration. In this article, we introduce cellular dosage forms that can be readily prepared from polymeric melts by incorporating the nucleation, growth, and coalescence of microscopic gas bubbles in a molding process. We show that the cell topology and formulation of such cellular structures can be engineered to reduce the length-scale of the mass-transfer step, which determines the time of drug release, from as large as the dosage form itself to as small as the thickness of the cell wall. This allows the cellular dosage forms to achieve drug release rates over an order of magnitude faster compared with those of cast matrices, spanning the entire spectrum of immediate-release and beyond. The melt-processed polymeric cellular dosage forms enable predictive design of immediate-release solid dosage forms by tailoring microstructures, and could be manufactured efficiently in a single step.

Design and fabrication of MEMS devices using the integration of MUMPs, trench-refilled molding, DRIE and bulk silicon etching processes

NASA Astrophysics Data System (ADS)

Wu, Mingching; Fang, Weileun

2005-03-01

This work integrates multi-depth DRIE etching, trench-refilled molding, two poly-Si layers MUMPs and bulk releasing to improve the variety and performance of MEMS devices. In summary, the present fabrication process, named MOSBE II, has three merits. First, this process can monolithically fabricate and integrate poly-Si thin-film structures with different thicknesses and stiffnesses, such as the flexible spring and the stiff mirror plate. Second, multi-depth structures, such as vertical comb electrodes, are available from the DRIE processes. Third, a cavity under the micromachined device is provided by the bulk silicon etching process, so that a large out-of-plane motion is allowed. In application, an optical scanner driven by the self-aligned vertical comb actuator was demonstrated. The poly-Si micromachined components fabricated by MOSBE II can further integrate with the MUMPs devices to establish a more powerful MOEMS platform.

High char yield epoxy curing agents

NASA Technical Reports Server (NTRS)

Delvigs, P.; Serafini, T. T.; Vanucci, R. D.

1981-01-01

Class of imide-amine curing agents preserves structural integrity, prevents fiber release, and is fully compatible with conventional epoxy resins; agents do not detract from composite properties while greatly reducing char yield. Materials utilizing curing are used in aerospace, automotive, and other structural components where deterioration must be minimized and fiber release avoided in event of fire.

Pre-release biological control agent recommendations for swallow-wort (Vincetoxicum spp.) informed by demographic matrix models

USDA-ARS?s Scientific Manuscript database

Weed biological control workers have advocated for the advance assessment of agent efficacy in order to minimize the release of host-specific but ineffective agents. One method involves demographic matrix modeling of target weed populations in order to identify plant life stage transitions that cont...

Liposome encapsulation of chelating agents

DOEpatents

Rahman, Yueh Erh

1976-01-13

A method for transferring a chelating agent across a cellular membrane by encapsulating the charged chelating agent within liposomes and carrying the liposome-encapsulated chelating agent to the cellular membrane where the liposomes containing the chelating agent will be taken up by the cells, thereby transferring the chelating agent across the cellular membrane. A chelating agent can be introduced into the interior of a cell of a living organism wherein the liposomes will be decomposed, releasing the chelating agent to the interior of the cell. The released chelating agent will complex intracellularly deposited toxic heavy metals, permitting the more soluble metal complex to transfer across the cellular membrane from the cell and subsequently be removed from the living organism.

Exposures to nanoparticles and fibers during injection molding and recycling of carbon nanotube reinforced polycarbonate composites.

PubMed

Boonruksa, Pongsit; Bello, Dhimiter; Zhang, Jinde; Isaacs, Jacqueline A; Mead, Joey L; Woskie, Susan R

2017-07-01

In this study, the characteristics of airborne particles generated during injection molding and grinding processes of carbon nanotube reinforced polycarbonate composites (CNT-PC) were investigated. Particle number concentration, size distribution, and morphology of particles emitted from the processes were determined using real-time particle sizers and transmission electron microscopy. The air samples near the operator's breathing zone were collected on filters and analyzed using scanning electron microscope for particle morphology and respirable fiber count. Processing and grinding during recycling of CNT-PC released airborne nanoparticles (NPs) with a geometric mean (GM) particle concentration from 4.7 × 10 3 to 1.7 × 10 6 particles/cm 3 . The ratios of the GM particle concentration measured during the injection molding process with exhaust ventilation relative to background were up to 1.3 (loading), 1.9 (melting), and 1.4 (molding), and 101.4 for grinding process without exhaust ventilation, suggesting substantial NP exposures during these processes. The estimated mass concentration was in the range of 1.6-95.2 μg/m 3 . Diverse particle morphologies, including NPs, NP agglomerates, particles with embedded or protruding CNTs and fibers, were observed. No free CNTs were found during any of the investigated processes. The breathing zone respirable fiber concentration during the grinding process ranged from non-detectable to 0.13 fiber/cm 3 . No evidence was found that the emissions were affected by the number of recycling cycles. Institution of exposure controls is recommended during these processes to limit exposures to airborne NPs and CNT-containing fibers.

Short- and long-term releases of fluorocarbons from disposal of polyurethane foam waste.

PubMed

Kjeldsen, Peter; Scheutz, Charlotte

2003-11-01

Several halocarbons having very high global warming or ozone depletion potentials have been used as a blowing agent (BA) for insulation foam in home appliances, such as refrigerators and freezers. Many appliances are shredded after the end of their useful life. Release experiments carried out in the laboratory on insulation foam blown with the blowing agents CFC-11, HCFC-141b, HCF-134fa, and HFC-245fa revealed that not all blowing agents are released during a 6-week period following the shredding process. The experiments confirmed the hypothesis that the release could be divided into three segments: By shredding foam panels, a proportion of the closed cells is either split or damaged to a degree allowing for a sudden release of the contained atmosphere in the cell (the instantaneous release). Cells adjacent to the cut surface may be only slightly damaged by tiny cracks or holes allowing a relative slow release of the BA to the surroundings (the short-term release). A significant portion of the cells in the foam particle will be unaffected and only allows release governed by slow diffusion through the PUR cell wall (the long-term release). The magnitude of the releases is for all three types highly dependent on how fine the foam is shredded. The residual blowing agent remaining after the 6-week period may be very slowly released if the integrity of the foam particles with respect to diffusion properties is kept after disposal of the foam waste on landfills. It is shown by setting up a national model simulating the BA releases following decommissioning of used domestic refrigerators/freezers in the United States that the release patterns are highly dependent on how the appliances are shredded.

The role of water in slip casting

NASA Technical Reports Server (NTRS)

Mccauley, R. A.; Phelps, G. W.

1984-01-01

Slips and casting are considered in terms of physical and colloidal chemistry. Casting slips are polydisperse suspensions of lyophobic particles in water, whose degree of coagulation is controlled by interaction of flocculating and deflocculating agents. Slip casting rate and viscosity are functions of temperature. Slip rheology and response to deflocculating agents varies significantly as the kinds and amounts of colloid modifiers change. Water is considered as a raw material. Various concepts of water/clay interactions and structures are discussed. Casting is a de-watering operation in which water moves from slip to cast to mold in response to a potential energy termed moisture stress. Drying is an evaporative process from a free water surface.

Lactobacillus plantarum with Broad Antifungal Activity as a Protective Starter Culture for Bread Production

PubMed Central

Russo, Pasquale; Longo, Angela; Spano, Giuseppe; Capozzi, Vittorio

2017-01-01

Bread is a staple food consumed worldwide on a daily basis. Fungal contamination of bread is a critical concern for producers since it is related to important economic losses and safety hazards due to the negative impact of sensorial quality and to the potential occurrence of mycotoxins. In this work, Lactobacillus plantarum UFG 121, a strain with characterized broad antifungal activity, was analyzed as a potential protective culture for bread production. Six different molds belonging to Aspergillus spp., Penicillium spp., and Fusarium culmorum were used to artificially contaminate bread produced with two experimental modes: (i) inoculation of the dough with a commercial Saccharomyces cerevisiae strain (control) and (ii) co-inoculation of the dough with the commercial S. cerevisiae strain and with L. plantarum UFG 121. L. plantarum strain completely inhibited the growth of F. culmorum after one week of storage. The lactic acid bacterium modulated the mold growth in samples contaminated with Aspergillus flavus, Penicillium chrysogenum, and Penicillium expansum, while no antagonistic effect was found against Aspergillus niger and Penicillium roqueforti. These results indicate the potential of L. plantarum UFG 121 as a biocontrol agent in bread production and suggest a species- or strain-depending sensitivity of the molds to the same microbial-based control strategy. PMID:29232917

Characterization of Potential Exposures to Nanoparticles and Fibers during Manufacturing and Recycling of Carbon Nanotube Reinforced Polypropylene Composites.

PubMed

Boonruksa, Pongsit; Bello, Dhimiter; Zhang, Jinde; Isaacs, Jacqueline A; Mead, Joey L; Woskie, Susan R

2016-01-01

Carbon nanotube (CNT) polymer composites are widely used as raw materials in multiple industries because of their excellent properties. This expansion, however, is accompanied by realistic concerns over potential release of CNTs and associated nanoparticles during the manufacturing, recycling, use, and disposal of CNT composite products. Such data continue to be limited, especially with regards to post-processing of CNT-enabled products, recycling and handling of nanowaste, and end-of-life disposal. This study investigated for the first time airborne nanoparticle and fibers exposures during injection molding and recycling of CNT polypropylene composites (CNT-PP) relative to that of PP. Exposure characterization focused on source emissions during loading, melting, molding, grinding, and recycling of scrap material over 20 cycles and included real-time characterization of total particle number concentration and size distribution, nanoparticle and fiber morphology, and fiber concentrations near the operator. Total airborne nanoparticle concentration emitted during loading, melting, molding, and grinding of CNT-PP had geometric mean ranging from 1.2 × 10(3) to 4.3 × 10(5) particles cm(-3), with the highest exposures being up to 2.9 and 300.7 times above the background for injection molding and grinding, respectively. Most of these emissions were similar to PP synthesis. Melting and molding of CNT-PP and PP produced exclusively nanoparticles. Grinding of CNT-PP but not PP generated larger particles with encapsulated CNTs, particles with CNT extrusions, and respirable fiber (up to 0.2 fibers cm(-3)). No free CNTs were found in any of the processes. The number of recycling runs had no significant impact on exposures. Further research into the chemical composition of the emitted nanoparticles is warranted. In the meanwhile, exposure controls should be instituted during processing and recycling of CNT-PP. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Inhibitory effect of gamma irradiation and its application for control of postharvest green mold decay of Satsuma mandarins.

PubMed

Jeong, Rae-Dong; Chu, Eun-Hee; Lee, Gun Woong; Cho, Chuloh; Park, Hae-Jun

2016-10-03

Gamma irradiation has been shown to be effective for the control of postharvest fungi in vitro, but little is known regarding antifungal action, responses to gamma irradiation, and its application to fresh produce. Gamma irradiation was evaluated for its in vitro and in vivo antifungal activity against Penicillium digitatum on Satsuma mandarin fruits. Green mold was inhibited in a dose-dependent manner. Gamma irradiation showed a complete inhibition of spore germination, germ tube elongation, and mycelial growth of P. digitatum, particularly at 1.0kGy. To further investigate the mechanisms by which gamma irradiation inhibits fungal growth, the membrane integrity and cellular leakage of conidia were tested, indicating that gamma irradiation results in the loss of plasma membrane integrity, causing the release of intracellular contents such as soluble proteins. In vivo assays demonstrated that established doses can completely inhibit the growth of fungal pathogens, but such high doses cause severe fruit damage. Thus, to eliminate the negative impact on fruit quality, gamma irradiation at lower doses was evaluated for inhibition of P. digitatum, in combination with a chlorine donor, sodium dichloro-s-triazinetrione (NaDCC). Interestingly, only a combined treatment with 0.4kGy of gamma irradiation and 10ppm of NaDCC exhibited significant synergistic antifungal activity against green mold decay. The mechanisms by which the combined treatment decreased the green mold decay of mandarin fruits can be directly associated with the disruption of cell membrane of the fungal pathogen, which resulted in a loss of cytoplasmic material from the hyphae. These findings suggest that a synergistic effect of combining treatment with gamma irradiation with NaDCC has potential as an antifungal approach to reduce the severity of green mold in mandarin fruits. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of anti-tacking agents on properties of gas-entrapped membrane and effervescent floating tablets.

PubMed

Kriangkrai, Worawut; Puttipipatkhachorn, Satit; Sriamornsak, Pornsak; Pongjanyakul, Thaned; Sungthongjeen, Srisagul

2014-12-01

Tackiness caused by the gas-entrapped membrane (Eudragit(®)RL 30D) was usually observed during storage of the effervescent floating tablets, leading to failure in floatation and sustained release. In this work, common anti-tacking agents (glyceryl monostearate (GMS) and talc) were used to solve this tackiness problem. The impact of anti-tacking agent on the properties of free films and corresponding floating tablets was investigated. GMS was more effective than talc in reducing tackiness of the film. Addition and increasing amount of anti-tacking agents lowered the film mechanical strength, but the coating films were still strong and flexible enough to resist the generated gas pressure inside the floating tablet. Wettability and water vapor permeability of the film decreased with increasing level of anti-tacking agents as a result of their hydrophobicity. No interaction between anti-tacking agents and polymer was observed as confirmed by Fourier transform infrared spectroscopy, powder X-ray diffractometry, and differential scanning calorimetry studies. Increasing amount of anti-tacking agents decreased time to float and tended to retard drug release of the floating tablets. Floating properties and drug release were also influenced by type of anti-tacking agents. The obtained floating tablets still possessed good floating properties and controlled drug release even though anti-tacking agent had some effects. The results demonstrated that the tackiness problem of the floating tablets could be solved by incorporating anti-tacking agent into the gas-entrapped membrane.

Predicting spillover risk to non-target plants pre-release: Bikasha collaris a potential biological control agent of Chinese tallowtree (Triadica sebifera)

USDA-ARS?s Scientific Manuscript database

Quarantine host range tests accurately predict direct risk of biological control agents to non-target species. However, a well-known indirect effect of biological control of weeds releases is spillover damage to non-target species. Spillover damage may occur when the population of agents achieves ou...

Benefits of pre-release population genetics: a case study using Psyttalia lounsburyi, a biocontrol agent of the olive fruit fly in California

USDA-ARS?s Scientific Manuscript database

From a pest management perspective, limited knowledge on the genetics of released biocontrol agents has been repeatedly considered as one possible cause of failures in classical biological control. Introduced biocontrol agents are expected to experience a loss in genetic diversity as the result of s...

Detection of the urban release of a bacillus anthracis simulant by air sampling.

PubMed

Garza, Alexander G; Van Cuyk, Sheila M; Brown, Michael J; Omberg, Kristin M

2014-01-01

In 2005 and 2009, the Pentagon Force Protection Agency (PFPA) staged deliberate releases of a commercially available organic pesticide containing Bacillus amyloliquefaciens to evaluate PFPA's biothreat response protocols. In concert with, but independent of, these releases, the Department of Homeland Security sponsored experiments to evaluate the efficacy of commonly employed air and surface sampling techniques for detection of an aerosolized biological agent. High-volume air samplers were placed in the expected downwind plume, and samples were collected before, during, and after the releases. Environmental surface and personal air samples were collected in the vicinity of the high-volume air samplers hours after the plume had dispersed. The results indicate it is feasible to detect the release of a biological agent in an urban area both during and after the release of a biological agent using high-volume air and environmental sampling techniques.

Imprint Characteristics by Photo-Induced Solidification of Liquid Polymer

NASA Astrophysics Data System (ADS)

Komuro, Masanori; Taniguchi, Jun; Inoue, Seiji; Kimura, Naoya; Tokano, Yuji; Hiroshima, Hiroshi; Matsui, Shinji

2000-12-01

Nanoimprint lithography is an attractive technology for LSIs era below 40-nm critical dimension from the viewpoints of high-throughput and low-cost equipment. In order to avoid a pattern placement error due to thermal expansion in the conventional thermal imprint process, we attempted to replicate the mold pattern onto a liquid polymer, which was solidified using ultra-violet (UV) light irradiation at room temperature. The liquid polymer used here was supplied by TEIJIN SEIKI Co., and termed TSR-820. It was spin coated on slide glass to produce approximately 1.5-μm-thick polymer film. The thickness remained after UV exposure and rinsing in acetone was observed at the dose of 10 J/cm2 and it saturated about a UV exposure dose of 100 J/cm2 with an increase in the exposure dose. The mold fabricated of quartz plate was first pressed onto the polymer film at about 100 kg/cm2 and then the UV light was irradiated using an imprint apparatus developed for this work. After releasing the mold from the film, the substrate was rinsed in acetone to remove the residual liquid polymer. Eventually the minimum feature size of 100-nm line and 300-nm space pattern was successfully replicated in the polymer with good fidelity.

Capability of air filters to retain airborne bacteria and molds in heating, ventilating and air-conditioning (HVAC) systems.

PubMed

Möritz, M; Peters, H; Nipko, B; Rüden, H

2001-07-01

The capability of air filters (filterclass: F6, F7) to retain airborne outdoor microorganisms was examined in field experiments in two heating, ventilating and air conditioning (HVAC) systems. At the beginning of the 15-month investigation period, the first filter stages of both HVAC systems were equipped with new unused air filters. The number of airborne bacteria and molds before and behind the filters were determined simultaneously in 14 days-intervals using 6-stage Andersen cascade impactors. Under relatively dry (< 80% R. H.) and warm (> 12 degrees C) outdoor air conditions air filters led to a marked reduction of airborne microorganism concentrations (bacteria by approximately 70% and molds by > 80%). However, during long periods of high relative humidity (> 80% R. H.) a proliferation of bacteria on air filters with subsequent release into the filtered air occurred. These microorganisms were mainly smaller than 1.1 microns therefore being part of the respirable fraction. The results showed furthermore that one possibility to avoid microbial proliferation is to limit the relative humidity in the area of the air filters to 80% R. H. (mean of 3 days), e.g. by using preheaters in front of air filters in HVAC-systems.

Interfacial Stacks of Polymeric Nanofilms on Soft Biological Surfaces that Release Multiple Agents.

PubMed

Herron, Maggie; Schurr, Michael J; Murphy, Christopher J; McAnulty, Jonathan F; Czuprynski, Charles J; Abbott, Nicholas L

2016-10-03

We report a general and facile method that permits the transfer (stacking) of multiple independently fabricated and nanoscopically thin polymeric films, each containing a distinct bioactive agent, onto soft biomedically relevant surfaces (e.g., collagen-based wound dressings). By using polyelectrolyte multilayer films (PEMs) formed from poly(allyl amine hydrochloride) and poly(acrylic acid) as representative polymeric nanofilms and micrometer-thick water-soluble poly(vinyl alcohol) sacrificial films to stack the PEMs, we demonstrate that it is possible to create stacked polymeric constructs containing multiple bioactive agents (e.g., antimicrobial and antibiofilm agents) on soft and chemically complex surfaces onto which PEMs cannot be routinely transferred by stamping. We illustrate the characteristics and merits of the approach by fabricating stacks of Ga 3+ (antibiofilm agent)- and Ag + (antimicrobial agent)-loaded PEMs as prototypical examples of agent-containing PEMs and demonstrate that the stacked PEMs incorporate precise loadings of the agents and provide flexibility in terms of tuning release rates. Specifically, we show that simultaneous release of Ga 3+ and Ag + from the stacked PEMs on collagen-based wound dressings can lead to synergistic effects on bacteria, killing and dispersing biofilms formed by Pseudomonas aeruginosa (two strains: ATCC 27853 and MPAO1) at sufficiently low loadings of agents such that cytotoxic effects on mammalian cells are avoided. The approach is general (a wide range of bioactive agents other than Ga 3+ and Ag + can be incorporated into PEMs), and the modular nature of the approach potentially allows end-user functionalization of soft biological surfaces for programmed release of multiple bioactive agents.

Influence of poloxamers on the dissolution performance and stability of controlled-release formulations containing Precirol ATO 5.

PubMed

Jannin, V; Pochard, E; Chambin, O

2006-02-17

Lipid excipients are usually used for the development of sustained-release formulations. When used in relatively high quantities, Precirol ATO 5 imparts sustained-release properties to solid oral dosage forms, by forming a lipid matrix. To control or adjust the drug release kinetics from such lipid matrix however, one must often resort to complementary ingredients or techniques. This study investigates the influence of poloxamers (Lutrol) included in lipid matrices composed of glyceryl palmitostearate (Precirol ATO 5) on their dissolution performance and their stability. The addition of these hydrophilic polymers in the lipid matrix increased the amount of theophylline released thanks to the swelling of the hydrophilic polymer and the creation of a porous network into the inert lipid matrix. The grade and the quantity of Lutrol could modulate the extent of drug release. Theophylline was released mainly by the matrix erosion but also by diffusion through the pores as suggested by the Peppas' model. Moreover, the addition of Lutrol enhanced the stability during storage. The theophylline release was quite steady after 6 months in different conditions (temperature and humidity). Thus, the mixture of glyceryl palmitostearate and poloxamers is an approach with many advantages for the development of controlled-release formulations by capsule molding.

Apparent competition can compromise the safety of highly specific biocontrol agents.

PubMed

Carvalheiro, Luisa G; Buckley, Yvonne M; Ventim, Rita; Fowler, Simon V; Memmott, Jane

2008-07-01

Despite current concern about the safety of biological control of weeds, assessing the indirect impacts of introduced agents is not common practice. Using 17 replicate food webs, we demonstrate that the use of a highly host-plant specific weed biocontrol agent, recently introduced into Australia, is associated with declines of local insect communities. The agent shares natural enemies (predators and parasitoids) with seed herbivore species from native plants, so apparent competition is the most likely cause for these losses. Both species richness and abundance in insect communities (seed herbivores and their parasitoids) were negatively correlated with the abundance of the biocontrol agent. Local losses of up to 11 species (dipteran seed herbivores and parasitoids) took place as the biocontrol agent abundance increased. Ineffective biocontrol agents that remain highly abundant in the community are most likely to have persistent, indirect negative effects. Our findings suggest that more investment is required in pre-release studies on the effectiveness of biocontrol agents, as well as in post-release studies assessing indirect impacts, to avoid or minimize the release of potentially damaging species.

Antibacterial activity and ion release of bonding agent containing amorphous calcium phosphate nanoparticles

PubMed Central

Chen, Chen; Weir, Michael D.; Cheng, Lei; Lin, Nancy; Lin-Gibson, Sheng; Chow, Laurence C.; Zhou, Xuedong; Xu, Hockin H. K.

2015-01-01

Objectives Recurrent caries at the margins is a primary reason for restoration failure. The objectives of this study were to develop bonding agent with the double benefits of antibacterial and remineralizing capabilities, to investigate the effects of NACP filler level and solution pH on Ca and P ion release from adhesive, and to examine the antibacterial and dentin bond properties. Methods Nanoparticles of amorphous calcium phosphate (NACP) and a quaternary ammonium monomer (dimethylaminododecyl methacrylate, DMADDM) were synthesized. Scotchbond Multi-Purpose (SBMP) primer and adhesive served as control. DMADDM was incorporated into primer and adhesive at 5% by mass. NACP was incorporated into adhesive at filler mass fractions of 10%, 20%, 30% and 40%. A dental plaque microcosm biofilm model was used to test the antibacterial bonding agents. Calcium (Ca) and phosphate (P) ion releases from the cured adhesive samples were measured vs. filler level and solution pH of 7, 5.5 and 4. Results Adding 5% DMADDM and 10–40% NACP into bonding agent, and water-aging for 28 days, did not affect dentin bond strength, compared to SBMP control at 1 day (p > 0.1). Adding DMADDM into bonding agent substantially decreased the biofilm metabolic activity and lactic acid production. Total microorganisms, total streptococci, and mutans streptococci were greatly reduced for bonding agents containing DMADDM. Increasing NACP filler level from 10% to 40% in adhesive increased the Ca and P ion release by an order of magnitude. Decreasing solution pH from 7 to 4 increased the ion release from adhesive by 6–10 folds. Significance Bonding agents containing antibacterial DMADDM and remineralizer NACP were formulated to have Ca and P ion release, which increased with NACP filler level from 10% to 40% in adhesive. NACP adhesive was “smart” and dramatically increased the ion release at cariogenic pH 4, when these ions would be most-needed to inhibit caries. Therefore, bonding agent containing DMADDM and NACP may be promising to inhibit biofilms and remineralize tooth lesions thereby increasing the restoration longevity. PMID:24954647

Antibacterial activity and ion release of bonding agent containing amorphous calcium phosphate nanoparticles.

PubMed

Chen, Chen; Weir, Michael D; Cheng, Lei; Lin, Nancy J; Lin-Gibson, Sheng; Chow, Laurence C; Zhou, Xuedong; Xu, Hockin H K

2014-08-01

Recurrent caries at the margins is a primary reason for restoration failure. The objectives of this study were to develop bonding agent with the double benefits of antibacterial and remineralizing capabilities, to investigate the effects of NACP filler level and solution pH on Ca and P ion release from adhesive, and to examine the antibacterial and dentin bond properties. Nanoparticles of amorphous calcium phosphate (NACP) and a quaternary ammonium monomer (dimethylaminododecyl methacrylate, DMADDM) were synthesized. Scotchbond Multi-Purpose (SBMP) primer and adhesive served as control. DMADDM was incorporated into primer and adhesive at 5% by mass. NACP was incorporated into adhesive at filler mass fractions of 10%, 20%, 30% and 40%. A dental plaque microcosm biofilm model was used to test the antibacterial bonding agents. Calcium (Ca) and phosphate (P) ion releases from the cured adhesive samples were measured vs. filler level and solution pH of 7, 5.5 and 4. Adding 5% DMADDM and 10-40% NACP into bonding agent, and water-aging for 28 days, did not affect dentin bond strength, compared to SBMP control at 1 day (p>0.1). Adding DMADDM into bonding agent substantially decreased the biofilm metabolic activity and lactic acid production. Total microorganisms, total streptococci, and mutans streptococci were greatly reduced for bonding agents containing DMADDM. Increasing NACP filler level from 10% to 40% in adhesive increased the Ca and P ion release by an order of magnitude. Decreasing solution pH from 7 to 4 increased the ion release from adhesive by 6-10 folds. Bonding agents containing antibacterial DMADDM and remineralizer NACP were formulated to have Ca and P ion release, which increased with NACP filler level from 10% to 40% in adhesive. NACP adhesive was "smart" and dramatically increased the ion release at cariogenic pH 4, when these ions would be most-needed to inhibit caries. Therefore, bonding agent containing DMADDM and NACP may be promising to inhibit biofilms and remineralize tooth lesions thereby increasing the restoration longevity. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Effect of UV-C radiation and vapor released from a water hyacinth root absorbent containing bergamot oil to control mold on storage of brown rice.

PubMed

Songsamoe, Sumethee; Matan, Narumol; Matan, Nirundorn

2016-03-01

The aims of this study were to develop absorbent material from a water hyacinth root containing bergamot oil and to improve its antifungal activity by using ultraviolet C (UV-C) against the growth of A. flavus on the brown rice. Process optimization was studied by the immersion of a water hyacinth root into a water and bergamot oil (300, 500 and 700 μl ml(-1)). The root (absorbent material) was dried at 50, 70, and 90 °C for 10 min. Then, ultraviolet C (UV-C) was used for enhancing the antifungal activity of bergamot oil for 10, 15, and 20 min. The shelf-life of the brown rice with the absorbent after incubation at 25 ° C with 100 % RH for 12 weeks was also investigated. A microscope and a Fourier transform infrared spectroscopy (FTIR) were used to find out possible mode of action. Results indicated that the absorbent material produced from the water hyacinth root containing bergamot oil at 500 μl ml(-1) in the water solution, dried at 70 ° C and UV for 15 min showed the highest antifungal activity in a vapor phase against A. flavus on the brown rice. A microscopy investigation confirmed that the water hyacinth root could absorb bergamot oil from an outside water solution into root cells. Limonene in vapor phase was shown to be a stronger inhibitor than essential oil after UV-C radiation and should be the key factor in boosting bergamot oil antifungal activity. A vapor phase of bergamot oil could be released and inhibit natural mold on the surface of the brown rice for up to 12 weeks; without the absorbent, mold covered the brown rice in only 4 weeks.

Preparation and cupric ion release behavior of Cu/LDPE porous composites with tunable pore morphology for intrauterine devices.

PubMed

Xiao, Lian; Xia, Xianping; Xie, Changsheng; Ge, Man; Xiao, Cheng; Cai, Shuizhou

2013-07-01

Copper/low-density polyethylene (Cu/LDPE) porous composites are novel materials for copper-containing intrauterine devices (Cu-IUDs). Here we report a method, i.e., by changing the mass ratio of two kinds of porogens that have different melting points through the combined techniques of injection molding and particulate leaching, to prepare the Cu/LDPE porous composites with tunable pore morphology. After these Cu/LDPE porous composites with different pore morphologies were obtained, the influences of pore morphologies on their cupric ion release behaviors were studied. The results show that the pore morphology has great influence on the cupric ion release behavior of Cu/LDPE porous composites. This phenomenon is caused by the different influences of different pore morphologies on the effective porosity and the surface hydrophilicity. And those results can be applied to guide the fabrication of Cu/LDPE porous composite Cu-IUDs with minimal weight at an appropriate cupric ion release rate. Copyright © 2013 Elsevier B.V. All rights reserved.

Development and Evaluation of High Bioavailable Sustained-Release Nimodipine Tablets Prepared with Monolithic Osmotic Pump Technology.

PubMed

Kong, Hua; Yu, Fanglin; Liu, Yan; Yang, Yang; Li, Mingyuan; Cheng, Xiaohui; Hu, Xiaoqin; Tang, Xuemei; Li, Zhiping; Mei, Xingguo

2018-01-01

Frequent administration caused by short half-life and low bioavailability due to poor solubility and low dissolution rate limit the further application of poorly water-soluble nimodipine, although several new indications have been developed. To overcome these shortcomings, sophisticated technologies had to be used since the dose of nimodipine was not too low and the addition of solubilizers could not resolve the problem of poor release. The purpose of this study was to obtain sustained and complete release of nimodipine with a simple and easily industrialized technology. The expandable monolithic osmotic pump tablets containing nimodipine combined with poloxamer 188 and carboxymethylcellulose sodium were prepared. The factors affecting drug release including the amount of solubilizing agent, expanding agent, retarding agent in core tablet and porogenic agent in semipermeable film were optimized. The release behavior was investigated both in vitro and in beagle dogs. It was proved that the anticipant release of nimodipine could be realized in vitro. The sustained and complete release of nimodipine was also realized in beagles because the mean residence time of nimodipine from the osmotic pump system was longer and Cmax was lower than those from the sustained-release tablets in market while there was no difference in AUC(0-t) of the monolithic osmotic pump tablets and the sustained release tablets in market. It was reasonable to believe that the sustained and complete release of poorly watersoluble nimodipine could be realized by using simple expandable monolithic osmotic pump technology combined with surfactant. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Identification of a consistent polyene component of purple pigment in diseased sclerites of Caribbean corals across region, species, and insult agent

NASA Astrophysics Data System (ADS)

Fetterolf, Monty L.; Leverette, Chad L.; Perez, Christopher; Smith, Garriet W.

2017-10-01

Gorgonians respond to insult (damage and disease) by producing sclerites containing a purple pigment as opposed to the normal white sclerites. Raman microscopy is used to study the purple areas of three species of diseased coral, Gorgonia ventalina, Pseudoplexaura porosa, and Eunicea laciniata obtained from Puerto Rico. These spectra were compared to Gorgonia ventalina samples previously reported that were obtained from San Salvador, Bahamas. Spectra from two samples of G. ventalina that had been infected by different agents, Aspergillus sydowii and a slime mold, were also obtained. The results indicate that the purple compounds (polyenes) generated by the coral in response to infection are similar regardless of region from which the coral were harvested, of species of coral, and of the infective agent. A discussion of the Raman spectra of G. ventalina and the other coral species is presented.

Structural wood panels with improved fire resistance

NASA Technical Reports Server (NTRS)

Sawko, P. M. (Inventor)

1980-01-01

Structural wood paneling or other molded wood compositions consisting of finely divided wood chips, flour, or strands are bound together and hot pressed with a modified novolac resin which is the cured product of a prepolymer made from an aralkyl ether or halide with a phenol and a hardening agent such as hexamethylene tetramine. The fire resistance of these articles is further improved by incorporating in the binder certain inorganic fillers, especially a mixture of ammonium oxalate and ammonium phosphate.

Optical Approaches for Drug Screening Based Light-Harvesting Conjugated Polyelectrolyte

DTIC Science & Technology

2010-03-01

membrane and inhibit spore germination/’ Aspergillus niger (A. niger ) was chosen for these studies since it is one of the most common species of the...We have also shown that the 𔃺: formation by PTP can be used to inhibit the growth of Aspergillus niger , which is more resistant than other fungi...genus Aspergillus , is more resistant to antimicrobial agents than other species such as Candida albicans,and is responsible for mold infections on

Bacillus methylotrophicus Strain NKG-1, Isolated from Changbai Mountain, China, Has Potential Applications as a Biofertilizer or Biocontrol Agent.

PubMed

Ge, Beibei; Liu, Binghua; Nwet, Thinn Thinn; Zhao, Wenjun; Shi, Liming; Zhang, Kecheng

2016-01-01

Chemical pesticides are widely used in agriculture, which endangers both environmental health and food safety. Biocontrol is an environmentally-friendly and cost-effective green technique in environmental protection and agricultural production; it generally uses selected bioresources, including beneficial microorganisms. We isolated a novel bacterial strain (NKG-1) from the rare dormant volcanic soils of Changbai Mountain in China's Jilin Province. The strain was identified as Bacillus methylotrophicus using morphological, biochemical, physiological, and phylogenetic 16S rDNA sequencing data. This strain was able to suppress mycelial growth and conidial germination of numerous plant pathogenic fungi on solid media. A greenhouse experiment showed that application of NKG-1 fermentation broth prior to inoculation of Botrytis cinerea, the cause of gray tomato mold, inhibited growth of the mold by 60%. Furthermore, application of a 100× dilution of NKG-1 fermentation broth to tomato seedlings yielded a significant increase in seedling fresh weight (27.4%), seedling length (12.5%), and root length (57.7%) compared to the control. When the same dosage was applied in the field, we observed increases in tomato plant height (14.7%), stem diameter (12.7%), crown width (16.3%), and maximum fruit diameter (11.5%). These results suggest that NKG-1 has potential commercial application as a biofertilizer or biocontrol agent.

Bacillus methylotrophicus Strain NKG-1, Isolated from Changbai Mountain, China, Has Potential Applications as a Biofertilizer or Biocontrol Agent

PubMed Central

Ge, Beibei; Liu, Binghua; Nwet, Thinn Thinn; Zhao, Wenjun; Shi, Liming; Zhang, Kecheng

2016-01-01

Chemical pesticides are widely used in agriculture, which endangers both environmental health and food safety. Biocontrol is an environmentally-friendly and cost-effective green technique in environmental protection and agricultural production; it generally uses selected bioresources, including beneficial microorganisms. We isolated a novel bacterial strain (NKG-1) from the rare dormant volcanic soils of Changbai Mountain in China’s Jilin Province. The strain was identified as Bacillus methylotrophicus using morphological, biochemical, physiological, and phylogenetic 16S rDNA sequencing data. This strain was able to suppress mycelial growth and conidial germination of numerous plant pathogenic fungi on solid media. A greenhouse experiment showed that application of NKG-1 fermentation broth prior to inoculation of Botrytis cinerea, the cause of gray tomato mold, inhibited growth of the mold by 60%. Furthermore, application of a 100× dilution of NKG-1 fermentation broth to tomato seedlings yielded a significant increase in seedling fresh weight (27.4%), seedling length (12.5%), and root length (57.7%) compared to the control. When the same dosage was applied in the field, we observed increases in tomato plant height (14.7%), stem diameter (12.7%), crown width (16.3%), and maximum fruit diameter (11.5%). These results suggest that NKG-1 has potential commercial application as a biofertilizer or biocontrol agent. PMID:27832162

Halloysite clay nanotubes for controlled release of protective agents.

PubMed

Lvov, Yuri M; Shchukin, Dmitry G; Möhwald, Helmuth; Price, Ronald R

2008-05-01

Halloysite aluminosilicate nanotubes with a 15 nm lumen, 50 nm external diameter, and length of 800 +/- 300 nm have been developed as an entrapment system for loading, storage, and controlled release of anticorrosion agents and biocides. Fundamental research to enable the control of release rates from hours to months is being undertaken. By variation of internal fluidic properties, the formation of nanoshells over the nanotubes and by creation of smart caps at the tube ends it is possible to develop further means of controlling the rate of release. Anticorrosive halloysite coatings are in development and a self-healing approach has been developed for repair mechanisms through response activation to external impacts. In this Perspective, applications of halloysite as nanometer-scale containers are discussed, including the use of halloysite tubes as drug releasing agents, as biomimetic reaction vessels, and as additives in biocide and protective coatings. Halloysite nanotubes are available in thousands of tons, and remain sophisticated and novel natural nanomaterials which can be used for the loading of agents for metal and plastic anticorrosion and biocide protection.

In Vitro Antifungal Susceptibility of Yeast and Mold Phases of Isolates of Dimorphic Fungal Pathogen Emergomyces africanus (Formerly Emmonsia sp.) from HIV-Infected South African Patients

PubMed Central

Britz, Erika; Zulu, Thokozile G.; Mpembe, Ruth S.; Naicker, Serisha D.; Schwartz, Ilan S.

2017-01-01

ABSTRACT Disseminated emmonsiosis is an important AIDS-related mycosis in South Africa that is caused by Emergomyces africanus, a newly described and renamed dimorphic fungal pathogen. In vitro antifungal susceptibility data can guide management. Identification of invasive clinical isolates was confirmed phenotypically and by sequencing of the internal transcribed spacer region. Yeast and mold phase MICs of fluconazole, voriconazole, itraconazole, posaconazole, caspofungin, anidulafungin, micafungin, and flucytosine were determined with custom-made frozen broth microdilution (BMD) panels in accordance with Clinical and Laboratory Standards Institute recommendations. MICs of amphotericin B, itraconazole, posaconazole, and voriconazole were determined by Etest. Fifty unique E. africanus isolates were tested. The yeast and mold phase geometric mean (GM) BMD and Etest MICs of itraconazole were 0.01 mg/liter. The voriconazole and posaconazole GM BMD MICs were 0.01 mg/liter for both phases, while the GM Etest MICs were 0.001 and 0.002 mg/liter, respectively. The fluconazole GM BMD MICs were 0.18 mg/liter for both phases. The GM Etest MICs of amphotericin B, for the yeast and mold phases were 0.03 and 0.01 mg/liter. The echinocandins and flucytosine had very limited in vitro activity. Treatment and outcome data were available for 37 patients; in a multivariable model including MIC data, only isolation from blood (odds ratio [OR], 8.6; 95% confidence interval [CI], 1.3 to 54.4; P = 0.02) or bone marrow (OR, 12.1; 95% CI, 1.2 to 120.2; P = 0.03) (versus skin biopsy) was associated with death. In vitro susceptibility data support the management of disseminated emmonsiosis with amphotericin B, followed by itraconazole, voriconazole, or posaconazole. Fluconazole was a relatively less potent agent. PMID:28356416

Calcium release rates from tooth enamel treated with dentifrices containing whitening agents and abrasives.

PubMed

Araujo, Danilo Barral; Silva, Luciana Rodrigues; de Araujo, Roberto Paulo Correia

2010-01-01

Tooth whitening agents containing hydrogen peroxide and carbamide peroxide are used frequently in esthetic dental procedures. However, lesions on the enamel surface have been attributed to the action of these products. Using conventional procedures for separating and isolating biological structures, powdered enamel was obtained and treated with hydrogen peroxide, carbamide peroxide, and sodium bicarbonate, ingredients typically found in dentifrices. The enamel was exposed to different pH levels, and atomic emission spectrometry was used to determine calcium release rates. As the pH level increased, the rate of calcium release from enamel treated with dentifrices containing whitening agents decreased. Carbamide peroxide produced the lowest amount of decalcification, while sodium bicarbonate produced the highest release rates at all pH levels.

Photocatalytic thin films coupled with polymeric microcapsules for the controlled-release of volatile agents upon solar activation

NASA Astrophysics Data System (ADS)

Oliveira, L. F.; Marques, J.; Coutinho, P. J. G.; Parpot, P.; Tavares, C. J.

2013-06-01

This work reportson the application of solar-activated photocatalytic thin films that allow the controlled-release of volatile agents (e.g., insecticides, repellents) from the interior of adsorbedpolymericmicrocapsules. In order to standardize the tests, a quantification of the inherent controlled-release of a particular volatile agent is determined by gas chromatography coupled to mass spectroscopy, so that an application can be offered to a wide range of supports from various industrial sectors, such as in textiles (clothing, curtains, mosquito nets). This technology takes advantage of the established photocatalytic property of titanium dioxide (TiO2) for the use as an active surface/site to promote the controlled-release of a specific vapor (volatile agentfrom within the aforementioned microcapsules.

Pre-release host range assessment for classical biological controls: experience with predators for the hemlock woolly adelgid

Treesearch

Elizabeth Butin; Montgomery Montgomery; Nathan Havill; Joseph Elkinton

2002-01-01

There are few regulations for the release of parasitoids and predators, compared to herbivorous arthropods and pathogens, used as classical biological control agents in the United States. The types of tests conducted prior to release of the predator or parasitoid into the environment are often up to the individual wishing to introduce the new agent. Ethical researchers...

Transmembrane myosin chitin synthase involved in mollusc shell formation produced in Dictyostelium is active

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schoenitzer, Veronika; Universitaet Regensburg, Biochemie I, Universitaetsstrasse 31, D-93053 Regensburg; Eichner, Norbert

Highlights: Black-Right-Pointing-Pointer Dictyostelium produces the 264 kDa myosin chitin synthase of bivalve mollusc Atrina. Black-Right-Pointing-Pointer Chitin synthase activity releases chitin, partly associated with the cell surface. Black-Right-Pointing-Pointer Membrane extracts of transgenic slime molds produce radiolabeled chitin in vitro. Black-Right-Pointing-Pointer Chitin producing Dictyostelium cells can be characterized by atomic force microscopy. Black-Right-Pointing-Pointer This model system enables us to study initial processes of chitin biomineralization. -- Abstract: Several mollusc shells contain chitin, which is formed by a transmembrane myosin motor enzyme. This protein could be involved in sensing mechanical and structural changes of the forming, mineralizing extracellular matrix. Here we report themore » heterologous expression of the transmembrane myosin chitin synthase Ar-CS1 of the bivalve mollusc Atrina rigida (2286 amino acid residues, M.W. 264 kDa/monomer) in Dictyostelium discoideum, a model organism for myosin motor proteins. Confocal laser scanning immunofluorescence microscopy (CLSM), chitin binding GFP detection of chitin on cells and released to the cell culture medium, and a radiochemical activity assay of membrane extracts revealed expression and enzymatic activity of the mollusc chitin synthase in transgenic slime mold cells. First high-resolution atomic force microscopy (AFM) images of Ar-CS1 transformed cellulose synthase deficient D. discoideumdcsA{sup -} cell lines are shown.« less

Fabrication of a microfluidic device for studying the in situ drug-loading/release behavior of graphene oxide-encapsulated hydrogel beads.

PubMed

Veerla, Sarath Chandra; Kim, Da Reum; Yang, Sung Yun

2018-01-01

Controlled drug delivery system is highly important for not only prolonged the efficacy of drug but also cellular development for tissue engineering. A number of biopolymer composites and nanostructured carriers behave been used for the controlled drug delivery of therapeutics. Recently, in vitro microfluidic devices that mimic the human body have been developed for drug-delivery applications. A microfluidic channel was fabricated via a two-step process: (i) polydimethyl siloxane (PDMS) and curing agent were poured with a 10:2 mass ratio onto an acrylic mold with two steel pipes, and (ii) calcium alginate beads were synthesized using sodium alginate and calcium chloride solutions. Different amounts (10, 25, 50 μg) of graphene oxide (GO) were then added by Hummers method, and studies on the encapsulation and release of the model drug, risedronate (Ris), were performed using control hydrogel beads (pH 6.3), GO-containing beads (10GO, 25GO and 50GO), and different pH conditions. MC3T3 osteoblastic cells were cultured in a microchannel with Ris-loaded GO-hydrogel beads, and their proliferation, viability, attachment and spreading were assessed for a week. The spongy and textured morphology of pristine hydrogel beads was converted to flowery and rod-shaped structures in drug-loaded hydrogel beads at reduced pH (6.3) and at a lower concentration (10 μg) of GO. These latter 10GO drug-loaded beads rapidly released their cargo owing to the calcium phosphate deposited on the surface. Notably, beads containing a higher amount of GO (50GO) exhibited an extended drug-release profile. We further found that MC3T3 cells proliferated continuously in vitro in the microfluidic channel containing the GO-hydrogel system. MTT and live/dead assays showed similar proliferative potential of MC3T3 cells. Therefore, a microfluidic device with microchannels containing hydrogel beads formulated with different amounts of GO and tested under various pH conditions could be a promising system for controlled drug release. The GO and drug (risedronate, Rig) were directed loaded into a hydrogel placed in a microchannel. Through interactions such as hydrogen bonding between Go and the Rig-loaded GO-hydrogel beads, the bead-loaded microfluidic device supported MC3T3 proliferation and development as osteoblast without additional osteogenic differentiation supplements.

Microbial Contents of Vacuum Cleaner Bag Dust and Emitted Bioaerosols and Their Implications for Human Exposure Indoors

PubMed Central

Veillette, Marc; Knibbs, Luke D.; Pelletier, Ariane; Charlebois, Remi; Blais Lecours, Pascale; He, Congrong; Morawska, Lidia

2013-01-01

Vacuum cleaners can release large concentrations of particles, both in their exhaust air and from resuspension of settled dust. However, the size, variability, and microbial diversity of these emissions are unknown, despite evidence to suggest they may contribute to allergic responses and infection transmission indoors. This study aimed to evaluate bioaerosol emission from various vacuum cleaners. We sampled the air in an experimental flow tunnel where vacuum cleaners were run, and their airborne emissions were sampled with closed-face cassettes. Dust samples were also collected from the dust bag. Total bacteria, total archaea, Penicillium/Aspergillus, and total Clostridium cluster 1 were quantified with specific quantitative PCR protocols, and emission rates were calculated. Clostridium botulinum and antibiotic resistance genes were detected in each sample using endpoint PCR. Bacterial diversity was also analyzed using denaturing gradient gel electrophoresis (DGGE), image analysis, and band sequencing. We demonstrated that emission of bacteria and molds (Penicillium/Aspergillus) can reach values as high as 1E5 cell equivalents/min and that those emissions are not related to each other. The bag dust bacterial and mold content was also consistent across the vacuums we assessed, reaching up to 1E7 bacterial or mold cell equivalents/g. Antibiotic resistance genes were detected in several samples. No archaea or C. botulinum was detected in any air samples. Diversity analyses showed that most bacteria are from human sources, in keeping with other recent results. These results highlight the potential capability of vacuum cleaners to disseminate appreciable quantities of molds and human-associated bacteria indoors and their role as a source of exposure to bioaerosols. PMID:23934489

A sacrificial process for fabrication of biodegradable polymer membranes with submicron thickness.

PubMed

Beardslee, Luke A; Stolwijk, Judith; Khaladj, Dimitrius A; Trebak, Mohamed; Halman, Justin; Torrejon, Karen Y; Niamsiri, Nuttawee; Bergkvist, Magnus

2016-08-01

A new sacrificial molding process using a single mask has been developed to fabricate ultrathin 2-dimensional membranes from several biocompatible polymeric materials. The fabrication process is similar to a sacrificial microelectromechanical systems (MEMS) process flow, where a mold is created from a material that can be coated with a biodegradable polymer and subsequently etched away, leaving behind a very thin polymer membrane. In this work, two different sacrificial mold materials, silicon dioxide (SiO2 ) and Liftoff Resist (LOR) were used. Three different biodegradable materials; polycaprolactone (PCL), poly(lactic-co-glycolic acid) (PLGA), and polyglycidyl methacrylate (PGMA), were chosen as model polymers. We demonstrate that this process is capable of fabricating 200-500 nm thin, through-hole polymer membranes with various geometries, pore-sizes and spatial features approaching 2.5 µm using a mold fabricated via a single contact photolithography exposure. In addition, the membranes can be mounted to support rings made from either SU8 or PCL for easy handling after release. Cell culture compatibility of the fabricated membranes was evaluated with human dermal microvascular endothelial cells (HDMECs) seeded onto the ultrathin porous membranes, where the cells grew and formed confluent layers with well-established cell-cell contacts. Furthermore, human trabecular meshwork cells (HTMCs) cultured on these scaffolds showed similar proliferation as on flat PCL substrates, further validating its compatibility. All together, these results demonstrated the feasibility of our sacrificial fabrication process to produce biocompatible, ultra-thin membranes with defined microstructures (i.e., pores) with the potential to be used as substrates for tissue engineering applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1192-1201, 2016. © 2015 Wiley Periodicals, Inc.

Nanostructured thermites based on iodine pentoxide for bio agent defeat systems.

NASA Astrophysics Data System (ADS)

Hobosyan, Mkhitar; Kazansky, Alexander; Martirosyan, Karen

2011-10-01

The risk for bioterrorist events involving the intentional airborne release of contagious agents has led to development of new approaches for bio agent defeat technologies both indoors and outdoors. Novel approaches to defeat harmful biological agents have generated a strong demand for new active materials. The preferred solutions are to neutralize the biological agents within the immediate target area by using aerosolized biocidal substances released in situ by high energetic reactions. By using nano-thermite reactions, with energy release up to 25 kJ/cc, based on I2O5/Al nanoparticles we intend to generate high quantity of vaporized iodine for spatial deposition onto harmful bacteria for their destruction. In this report, the effect of reaction product on growth and survival of Escherichia coli (E-coli) expressing GFP (Green Fluorescent Protein) was investigated. Moreover, we developed an approach to increase sensitivity of the detection. The study has shown that I2O5/Al nanosystem is extremely effective to disinfect harmful biological agents such (E-coli) bacteria in seconds.

[Deep skin infection with Scedosporium apiospermum-infection in a renal transplant patient].

PubMed

Strunk, T; Blume, J-H; Szeimies, R-M

2015-03-01

A 57-year-old immunosuppressed patient presented with multiple erythematous papules and pustules as well as isolated ulcerations on the right lower leg and subcutaneous nodules on the right thigh. The biopsy revealed granulomatous inflammation with numerous fungal hyphae, which were IDentified as Scedosporium apiospermum by PCR. He was treated with voriconazole 2 × 200 mg daily as well assurgical debridement. Scedosporium apiospermum is a rare pathogenic agent of deep mold fungus infections. Skin infections with Scedosporium apiospermum are underdiagnosed because of different clinical manifestations. In immunosuppressed patients, an infection represents a potentially life-threatening complication. Precise identification of the agent with introduction of antimycotic therapy appears to be pivotal to prevent fulminant disease.

Evaluation of proposed Skylab and SSP soap products

NASA Technical Reports Server (NTRS)

Whitmore, F. C.; Durfee, R. L.; Spurlock, J. M.

1973-01-01

Three personal hygiene cleansing agents and one laundry detergent (sodium dodecyl benzene sulfonate), which are all candidates for use on long-duration space missions, were evaluated in terms of dermatological effects on human subjects and effects on microbiological species. None of the four materials exhibited adverse dermatological effects from either skin patch tests of two weeks duration or a simulated Skylab personal hygiene regimen of up to four weeks duration. No significant alterations in skin microflora during the use regimen were found. None of the four materials were found to serve as microbiological support media for the species tested, but a species of air-borne mold was observed to grow rapidly in a neutralized aqueous solution. None of the candidate agents was found to be strongly biocidal.

Colon targeted delivery systems of metronidazole based on osmotic technology: development and evaluation.

PubMed

Kumar, Pramod; Singh, Sanjay; Mishra, Brahmeshwar

2008-09-01

Colon targeted delivery systems of metronidazole (MTZ) based on osmotic technology were developed. The developed systems consisted of osmotic core (drug, osmotic agent and wicking agent), coated with semipermeable membrane (SPM) containing guar gum as pore former, coated core were then further coated with enteric coating to protect the system from acidic environment of stomach. The effect of various formulation variables namely the level of wicking agent (sodium lauryl sulphate), osmotic agent in the osmotic core, the level of pore former (guar gum) in SPM, and the thickness of SPM, were studied on physical parameters and drug release characteristics of developed formulations. MTZ release was inversely proportional to SPM thickness, but directly related to the level of pore former, wicking agent and osmotic agent. On the other hand burst strength of the exhausted shells was decreased with the increase in level of pore former in the membrane but increased with the increase in the thickness of SPM. The drug release from the developed formulations was independent of pH, and agitation intensity, but dependent on the osmotic pressure of the release media. The thickness of enteric coating could prevent formation of delivery pores before contact with simulated colonic fluid, but had no effect on drug release. Result of SEM studies showed the formation of in-situ delivery pores in the membrane from where the drug release occurred, and the number of pores formed were directly related to the initial level of pore former (guar gum) in SPM. The manufacturing procedure was found to be reproducible and formulations were found to be stable during 3 months of accelerated stability studies.

Purification, Cloning and Immuno-Biochemical Characterization of a Fungal Aspartic Protease Allergen Rhi o 1 from the Airborne Mold Rhizopus oryzae

PubMed Central

Sircar, Gaurab; Saha, Bodhisattwa; Mandal, Rahul Shubhra; Pandey, Naren; Saha, Sudipto; Gupta Bhattacharya, Swati

2015-01-01

Background Fungal allergy is considered as serious health problem worldwide and is increasing at an alarming rate in the industrialized areas. Rhizopus oyzae is a ubiquitously present airborne pathogenic mold and an important source of inhalant allergens for the atopic population of India. Here, we report the biochemical and immunological features of its 44 kDa sero-reactive aspartic protease allergen, which is given the official designation ‘Rhi o 1’. Method The natural Rhi o 1 was purified by sequential column chromatography and its amino acid sequence was determined by mass spectrometry and N-terminal sequencing. Based on its amino acid sequence, the cDNA sequence was identified, cloned and expressed to produce recombinant Rhi o 1. The allergenic activity of rRhi o 1 was assessed by means of its IgE reactivity and histamine release ability. The biochemical property of Rhi o 1 was studied by enzyme assay. IgE-inhibition experiments were performed to identify its cross-reactivity with the German cockroach aspartic protease allergen Bla g 2. For precise characterization of the cross-reactive epitope, we used anti-Bla g 2 monoclonal antibodies for their antigenic specificity towards Rhi o 1. A homology based model of Rhi o 1 was built and mapping of the cross-reactive conformational epitope was done using certain in silico structural studies. Results The purified natural nRhi o 1 was identified as an endopeptidase. The full length allergen cDNA was expressed and purified as recombinant rRhi o 1. Purified rRhi o 1 displayed complete allergenicity similar to the native nRhi o 1. It was recognized by the serum IgE of the selected mold allergy patients and efficiently induced histamine release from the sensitized PBMC cells. This allergen was identified as an active aspartic protease functional in low pH. The Rhi o 1 showed cross reactivity with the cockroach allergen Bla g 2, as it can inhibit IgE binding to rBla g 2 up to certain level. The rBla g 2 was also found to cross-stimulate histamine release from the effector cells sensitized with anti-Rhi o 1 serum IgE. This cross-reactivity was found to be mediated by a common mAb4C3 recognizable conformational epitope. Bioinformatic studies revealed high degree of structural resemblances between the 4C3 binding sites of both the allergens. Conclusion/Significance The present study reports for the first time anew fungal aspartic protease allergen designated as Rhi o 1, which triggers IgE-mediated sensitization leading to various allergic diseases. Here we have characterized the recombinant Rhi o 1 and its immunological features including cross-reactive epitope information that will facilitate the component-resolved diagnosis of mold allergy. PMID:26672984

Ristocetin induces phosphorylated-HSP27 (HSPB1) release from the platelets of type 2 DM patients: Anti-platelet agent-effect on the release.

PubMed

Tokuda, Haruhiko; Kuroyanagi, Gen; Onuma, Takashi; Enomoto, Yukiko; Doi, Tomoaki; Iida, Hiroki; Otsuka, Takanobu; Ogura, Shinji; Iwama, Toru; Kojima, Kumi; Kozawa, Osamu

2018-04-01

It has been previously reported that HSP27 is released from platelets in type 2 diabetes mellitus (DM) patients according to phosphorylation. In the present study, we investigated the effect of ristocetin, a glycoprotein (GP)Ib/IX/V activator, on the release of HSP27 and the effect of anti-platelet agents, such as acetylsalicylic acid (ASA), on this release. Forty-six patients with type 2 DM were recruited, and classified into two groups depending on administration of anti-platelet agents, resulting in 31 patients without these agents (control group) and 15 patients with them (anti-platelet group). Ristocetin potently induced the aggregation of platelets in the two groups. Ristocetin-induced changes of the area under the curve of light transmittance and the ratio of the size of platelet aggregates in the anti-platelet group were slightly different from those in the control group. On the other hand, the levels of phosphorylated-HSP27 induced by ristocetin in the platelets from a patient of the anti-platelet group taking ASA were significantly lower than those from a patient of the control group. The levels of HSP27 release from the ristocetin-stimulated platelets were significantly correlated with the levels of phosphorylated-HSP27 in the platelets from patients in the two groups. The levels of HSP27 release and those of platelet-derived growth factor-AB (PDGF-AB) secretion stimulated by ristocetin in the anti-platelet group were lower than those in the control group. In addition, the levels of HSP27 release and those of PDGF-AB secretion stimulated by ADP in the anti-platelet group were lower than those in the control group. These results strongly suggest that anti-platelet agents inhibit the HSP27 release from platelets stimulated by ristocetin but not the aggregation in type 2 DM patients.

Insulin-releasing action of the novel antidiabetic agent BTS 67 582.

PubMed

McClenaghan, N H; Flatt, P R; Bailey, C J

1998-02-01

1. BTS 67582 (1,1-dimethyl-2-(2-morpholinophenyl)guanidine fumarate) is a novel antidiabetic agent with a short-acting insulin-releasing effect. This study examined its mode of action in the clonal B-cell line BRIN-BD11. 2. BTS 67582 increased insulin release from BRIN-BD11 cells in a concentration-dependent manner (10[-8] to 10[-4] M) at both non-stimulating (1.1 mM) and stimulating (16.7 mM) concentrations of glucose. 3. BTS 67582 (10[-4] M) potentiated the insulin-releasing effect of a depolarizing concentration of K+ (30 mM), whereas the K+ channel openers pinacidil (400 microM) and diazoxide (300 microM) inhibited BTS 67582-induced release. 4. Suppression of Ca+ channel activity with verapamil (20 microM) reduced the insulin-releasing effect of BTS 67582 (10[-4] M). 5. BTS 67582 (10[-4] M) potentiated insulin release induced by amino acids (10 mM), and enhanced the combined stimulant effects of glucose plus either the fatty acid palmitate (10 mM), or agents which raise intracellular cyclic AMP concentrations (25 microM forskolin and 1 mM isobutylmethylxanthine), or the cholinoceptor agonist carbachol (100 microM). 6. Inhibition of glucose-stimulated insulin release by adrenaline or noradrenaline (10 microM) was partially reversed by BTS 67582 (10[-4] M). 7. These data suggest that the insulin-releasing effect of BTS 67582 involves regulation of ATP-sensitive K+ channel activity and Ca2+ influx, and that the drug augments the stimulant effects of nutrient insulin secretagogues and agents which enhance adenylate cyclase and phospholipase C. BTS 67582 may also exert insulin-releasing effects independently of ATP-sensitive K+ channel activity.

Integrated hot-melt extrusion - injection molding continuous tablet manufacturing platform: Effects of critical process parameters and formulation attributes on product robustness and dimensional stability.

PubMed

Desai, Parind M; Hogan, Rachael C; Brancazio, David; Puri, Vibha; Jensen, Keith D; Chun, Jung-Hoon; Myerson, Allan S; Trout, Bernhardt L

2017-10-05

This study provides a framework for robust tablet development using an integrated hot-melt extrusion-injection molding (IM) continuous manufacturing platform. Griseofulvin, maltodextrin, xylitol and lactose were employed as drug, carrier, plasticizer and reinforcing agent respectively. A pre-blended drug-excipient mixture was fed from a loss-in-weight feeder to a twin-screw extruder. The extrudate was subsequently injected directly into the integrated IM unit and molded into tablets. Tablets were stored in different storage conditions up to 20 weeks to monitor physical stability and were evaluated by polarized light microscopy, DSC, SEM, XRD and dissolution analysis. Optimized injection pressure provided robust tablet formulations. Tablets manufactured at low and high injection pressures exhibited the flaws of sink marks and flashing respectively. Higher solidification temperature during IM process reduced the thermal induced residual stress and prevented chipping and cracking issues. Polarized light microscopy revealed a homogeneous dispersion of crystalline griseofulvin in an amorphous matrix. DSC underpinned the effect of high tablet residual moisture on maltodextrin-xylitol phase separation that resulted in dimensional instability. Tablets with low residual moisture demonstrated long term dimensional stability. This study serves as a model for IM tablet formulations for mechanistic understanding of critical process parameters and formulation attributes required for optimal product performance. Copyright © 2017 Elsevier B.V. All rights reserved.

Botrytis californica, a new cryptic species in the B. cinerea species complex causing gray mold in blueberries and table grapes.

PubMed

Saito, S; Margosan, D; Michailides, T J; Xiao, C L

2016-01-01

The Botrytis cinerea species complex comprises two cryptic species, originally referred to Group I and Group II based on Bc-hch gene RFLP haplotyping. Group I was described as a new cryptic species B. pseudocinerea During a survey of Botrytis spp. causing gray mold in blueberries and table grapes in the Central Valley of California, six isolates, three from blueberries and three from table grapes, were placed in Group I but had a distinct morphological character with conidiophores significantly longer than those of B. cinerea and B. pseudocinerea We compared these with B. cinerea and B. pseudocinerea by examining morphological and physiological characters, sensitivity to fenhexamid and phylogenetic analysis inferred from sequences of three nuclear genes. Phylogenetic analysis with the three partial gene sequences encoding glyceraldehyde-3-phosate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60) and DNA-dependent RNA polymerase subunit II (RPB2) supported the proposal of a new Botrytis species, B. californica, which is closely related genetically to B. cinerea, B. pseudocinerea and B. sinoviticola, all known as causal agents of gray mold of grapes. Botrytis californica caused decay on blueberry and table grape fruit inoculated with the fungus. This study suggests that B. californica is a cryptic species sympatric with B. cinerea on blueberries and table grapes in California. © 2016 by The Mycological Society of America.

Aureobasidium pullulansas a biocontrol agent of blue mold in "Rocha" pear.

PubMed

Ferreira-Pinto, M M; Moura-Guedes, M C; Barreiro, M G; Pais, I; Santos, M R; Silva, M J

2006-01-01

The blue mold of "Rocha" pear caused by Penicillium expansum is an important postharvest disease which is adequately controlled by application of synthetic fungicides. In recent years, strategies like biological control have been considered a desirable alternative to chemicals. Several studies have demonstrated the potential of the yeast-like fungus Aureobasidium pullulans for control of postharvest decay of pear. A Portuguese isolate of Aureobasidium pullulans was characterized and evaluated for its activity in reducing postharvest blue mold decay of "Rocha" pear caused by Penicillium expansum. Study of optimal conditions for antagonist growth was carried out in six different culture media. The effect of four maturity stages of fruits in the development of A. pullulans was also studied. Biocontrol studies were performed with two concentrations of the antagonist (3 x 10(8) and 4 x 10(9) CFU/ml). A. pullulans growth was significantly different (P < or = 0.001) according to the various media and time of incubation. Best results were obtained in Corn Meal Agar (CMA) and Potato Dextrose Agar (PDA) media which contains the higher concentration of glucose (20 mg/l). Medium resulted from fruits of the first harvest date presented lower colony diameter. Inoculation of A. pullulans at 3 x 10(8) and 4 x 10(9) CFU/ml reduced the incidence of the disease by 23 and 63%, and reduced the lesion diameter by 36 and 46%, respectively.

A homolog of Escherichia coli RecA in mitochondria of the cellular slime mold Dictyostelium discoideum.

PubMed

Hasegawa, Yasuna; Wakabayashi, Masayuki; Nakamura, Shogo; Kodaira, Ken-ichi; Shinohara, Hiroaki; Yasukawa, Hiro

2004-05-04

The cellular slime mold Dictyostelium discoideum expresses a gene encoding a 452-amino-acid polypeptide that is 47% identical to Escherichia coli RecA. A recA-deficient E. coli, JE6651, was transformed by pYSN1, which was designed to express the truncated form of the D. discoideum gene, and used in suppression assays. The viability of the transformant, JE6651(pYSN1), increased following UV irradiation or mitomycin C treatment. Phage lambda (red(-) gam(-)), which required RecA activity for DNA packaging, formed plaques on a lawn of JE6651(pYSN1). These results indicate that the gene product has a DNA recombination activity. Fluorescence of D. discoideum protein fused with GFP was detected in mitochondria. The gene disruption mutant was hypersensitive to UV-light (254nm), mitomycin C and H(2)O(2), indicating that D. discoideum recA is important for survival following exposure to DNA damaging agents.

Shrink-Induced Superhydrophobic and Antibacterial Surfaces in Consumer Plastics

PubMed Central

Freschauf, Lauren R.; McLane, Jolie; Sharma, Himanshu; Khine, Michelle

2012-01-01

Structurally modified superhydrophobic surfaces have become particularly desirable as stable antibacterial surfaces. Because their self-cleaning and water resistant properties prohibit bacteria growth, structurally modified superhydrophobic surfaces obviate bacterial resistance common with chemical agents, and therefore a robust and stable means to prevent bacteria growth is possible. In this study, we present a rapid fabrication method for creating such superhydrophobic surfaces in consumer hard plastic materials with resulting antibacterial effects. To replace complex fabrication materials and techniques, the initial mold is made with commodity shrink-wrap film and is compatible with large plastic roll-to-roll manufacturing and scale-up techniques. This method involves a purely structural modification free of chemical additives leading to its inherent consistency over time and successive recasting from the same molds. Finally, antibacterial properties are demonstrated in polystyrene (PS), polycarbonate (PC), and polyethylene (PE) by demonstrating the prevention of gram-negative Escherichia coli (E. coli) bacteria growth on our structured plastic surfaces. PMID:22916100

[Research of preparation craft of Danshen phenolic acid fast release unit in multi-drug delivery system of Tongmai micro-pellets].

PubMed

Chen, Bin; Xiao, Wei; Jia, Xiao-Bin; Huang, Yang

2012-07-01

To prepare Danshen phenolic acid fast release micro-pellets and study its preparation craft. The factors which could impact yield, extrude shaping, dissolution of Danshen phenolic acid micro-pellets such as wetting agent, drug loading dose, adjuvant, lactose dose, disintegrant, CMS-Na dose and wetting agent dose was investigated. The optimum preparation craft of Danshen phenolic acid fast release micro-pellets was screened out by orhogonal design. Formula of Danshen phenolic acid fast release micro-pellets was calculated as volume dose 50 g. The formula was as follows: principal agent 22.5 g, lactose 5 g, CMS-Na 2 g, MCC 20.5 g, 27 mL 30% ethanol as wetting agent. Extrusion-spheronization was applied. The optimum conditions were screened out as follows: extrusion frequency (25 Hz), spheronization machine frequency (50 Hz), spheronization time (4 min). The process was scientific and rational. The preparation is stable settles basis for multi-drug delivery system of Tongmai micro-pellets.

Evaluation of Degradation Properties of Polyglycolide and Its Potential as Delivery Vehicle for Anticancer Agents

NASA Astrophysics Data System (ADS)

Noorsal, K.; Ghani, S. M.; Yunos, D. M.; Mohamed, M. S. W.; Yahya, A. F.

2010-03-01

Biodegradable polymers offer a unique combination of properties that can be tailored to suit nearly any controlled drug delivery application. The most common biodegradable polymers used for biomedical applications are semicrystalline polyesters and polyethers which possess good mechanical properties and have been used in many controlled release applications. Drug release from these polymers may be controlled by several mechanisms and these include diffusion of drug through a matrix, dissolution of polymer matrix and degradation of the polymer. This study aims to investigate the degradation and drug release properties of polyglycolide (1.03 dL/g), in which, cis platin, an anticancer agent was used as the model drug. The degradation behaviour of the chosen polymer is thought to largely govern the release of the anticancer agent in vitro.

Evaluation of a Lightweight Protective Mask Concept for Respiratory Protection System 21

DTIC Science & Technology

1992-01-01

In addition, the LPM should provide a comfortable fit to reduce the physiological burden on the solder. The M40 mask is molded of silicone rubber ...for low temperature flexibility and romfort even though this material doesn’t providr. a good chemical agent barrier. Also, the M40 uses thick rubber ...Latex BL-100 (Appeadix D, no. 32) with natural rubber latex 1041, (Firestone), and by evenly mixing polyisobutylene latem I (PIB-5C) with natural

Naval War College Review. Volume 42, Number 3, Sequence 327, Summer 1989

DTIC Science & Technology

1989-07-01

34usability" of biological agents. 12 Naval War College Review One school of thought suggests that there may be less to the new developments in life ...genes are the memory bank for our species-the cell’s floppy disk governing all life processes at the molecular level. Precise mapping of such genetic...34 Allegedly, this campaign targeted vital crops such as tobacco (blue mold) and sugar cane (cane smut), livestock (African swine fever), and also the

Tablet coating by injection molding technology - Optimization of coating formulation attributes and coating process parameters.

PubMed

Desai, Parind M; Puri, Vibha; Brancazio, David; Halkude, Bhakti S; Hartman, Jeremy E; Wahane, Aniket V; Martinez, Alexander R; Jensen, Keith D; Harinath, Eranda; Braatz, Richard D; Chun, Jung-Hoon; Trout, Bernhardt L

2018-01-01

We developed and evaluated a solvent-free injection molding (IM) coating technology that could be suitable for continuous manufacturing via incorporation with IM tableting. Coating formulations (coating polymers and plasticizers) were prepared using hot-melt extrusion and screened via stress-strain analysis employing a universal testing machine. Selected coating formulations were studied for their melt flow characteristics. Tablets were coated using a vertical injection molding unit. Process parameters like softening temperature, injection pressure, and cooling temperature played a very important role in IM coating processing. IM coating employing polyethylene oxide (PEO) based formulations required sufficient room humidity (>30% RH) to avoid immediate cracks, whereas other formulations were insensitive to the room humidity. Tested formulations based on Eudrajit E PO and Kollicoat IR had unsuitable mechanical properties. Three coating formulations based on hydroxypropyl pea starch, PEO 1,000,000 and Opadry had favorable mechanical (<700MPa Young's modulus, >35% elongation, >95×10 4 J/m 3 toughness) and melt flow (>0.4g/min) characteristics, that rendered acceptable IM coats. These three formulations increased the dissolution time by 10, 15 and 35min, respectively (75% drug release), compared to the uncoated tablets (15min). Coated tablets stored in several environmental conditions remained stable to cracking for the evaluated 8-week time period. Copyright © 2017 Elsevier B.V. All rights reserved.

An Investigation into the Effects of Sprue Attachment Design on Porosity and Castability

DTIC Science & Technology

1990-12-01

of a dental alloy: sprue design, mold temperature, fusing and casting temperature of the alloy, type of casting machine, casting force, burnout time... Student at: University of Texas, San Antonio AFIT/CI/CIA-90-119 AFIT/CI Wright-Patterson AFB OH 45433-6583 Approved for Public Release IAW AFR 190-1...Supervising Professor: E. Steven Duke, D.D.S., M.S.D. Many variables are involved in the process of fabricating a dense dental casting which accurately

Manufacturing plastic injection optical molds

NASA Astrophysics Data System (ADS)

Bourque, David

2008-08-01

ABCO Tool & Die, Inc. is a mold manufacturer specializing in the manufacturing of plastic injection molds for molded optical parts. The purpose of this presentation is to explain the concepts and procedures required to build a mold that produces precision optical parts. Optical molds can produce a variety of molded parts ranging from safety eyewear to sophisticated military lens parts, which must meet precise optical specifications. The manufacturing of these molds begins with the design engineering of precision optical components. The mold design and the related optical inserts are determined based upon the specific optical criteria and optical surface geometry. The mold manufacturing techniques will be based upon the optical surface geometry requirements and specific details. Manufacturing processes used will be specific to prescribed geometrical surface requirements of the molded part. The combined efforts result in a robust optical mold which can produce molded parts that meet the most precise optical specifications.

Rhinosinusitis and mold as risk factors for asthma symptoms in occupants of a water-damaged building.

PubMed

Park, J-H; Kreiss, K; Cox-Ganser, J M

2012-10-01

Mold exposure in damp buildings is associated with both nasal symptoms and asthma development, but the progression of building-related (BR) rhinosinusitis symptoms to asthma is unstudied. We examined the risk of developing BR-asthma symptoms in relation to prior BR-rhinosinusitis symptoms and microbial exposure among occupants of a damp building. We conducted four cross-sectional health and environmental surveys among occupants of a 20-story water-damaged office building. We defined BR-rhinosinusitis symptom (N=131) and comparison (N=361) groups from participants' first questionnaire responses. We compared the odds for the development of BR-asthma symptoms between these two groups over the subsequent surveys, using logistic regression models adjusted for demographics, smoking, building tenure, and first-survey exposures to fungi, endotoxin, and ergosterol. The BR-rhinosinusitis symptom group had higher odds for developing BR-asthma symptoms [odds ratio (OR)=2.2; 95% confidence interval (CI)=1.3-3.6] in any subsequent survey compared to those without BR-rhinosinusitis symptoms. The BR-rhinosinusitis symptom group with higher fungal exposure within the building had an OR of 7.4 (95% CI=2.8-19.9) for developing BR-asthma symptoms, compared to the lower fungal exposure group without BR-rhinosinusitis symptoms. Our findings suggest that rhinosinusitis associated with occupancy of water-damaged buildings may be a sentinel for increased risk for asthma onset in such buildings. Exposure to mold is associated with the development of asthma in damp building occupants, and rhinitis is known to be a risk factor for asthma. However, there is little information about the degree of risk for the progression of rhinosinusitis to asthma owing to mold exposures in damp buildings. Our study of damp building occupants demonstrates that building-related (BR) rhinosinusitis symptoms were a risk factor for the development of BR asthma symptoms and that exposure to mold (fungi) or other dampness-related agents augments risk for the development of BR asthma symptoms among those with BR rhinosinusitis symptoms. Our findings suggest that occurrence of BR upper respiratory illness in water-damaged buildings may presage future endemic asthma. © 2012 John Wiley & Sons A/S.

Association of residential dampness and mold with respiratory tract infections and bronchitis: a meta-analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisk, William J.; Eliseeva, Ekaterina A.; Mendell, Mark J.

Dampness and mold have been shown in qualitative reviews to be associated with a variety of adverse respiratory health effects, including respiratory tract infections. Several published meta-analyses have provided quantitative summaries for some of these associations, but not for respiratory infections. Demonstrating a causal relationship between dampness-related agents, which are preventable exposures, and respiratory tract infections would suggest important new public health strategies. We report the results of quantitative meta-analyses of published studies that examined the association of dampness or mold in homes with respiratory infections and bronchitis. For primary studies meeting eligibility criteria, we transformed reported odds ratios (ORs)more » and confidence intervals (CIs) to the log scale. Both fixed and random effects models were applied to the log ORs and their variances. Most studies contained multiple estimated ORs. Models accounted for the correlation between multiple results within the studies analyzed. One set of analyses was performed with all eligible studies, and another set restricted to studies that controlled for age, gender, smoking, and socioeconomic status. Subgroups of studies were assessed to explore heterogeneity. Funnel plots were used to assess publication bias. The resulting summary estimates of ORs from random effects models based on all studies ranged from 1.38 to 1.50, with 95% CIs excluding the null in all cases. Use of different analysis models and restricting analyses based on control of multiple confounding variables changed findings only slightly. ORs (95% CIs) from random effects models using studies adjusting for major confounding variables were, for bronchitis, 1.45 (1.32-1.59); for respiratory infections, 1.44 (1.31-1.59); for respiratory infections excluding nonspecific upper respiratory infections, 1.50 (1.32-1.70), and for respiratory infections in children or infants, 1.48 (1.33-1.65). Little effect of publication bias was evident. Estimated attributable risk proportions ranged from 8% to 20%. Residential dampness and mold are associated with substantial and statistically significant increases in both respiratory infections and bronchitis. If these associations were confirmed as causal, effective control of dampness and mold in buildings would prevent a substantial proportion of respiratory infections.« less

Controlled release of cyclosporine A self-nanoemulsifying systems from osmotic pump tablets: near zero-order release and pharmacokinetics in dogs.

PubMed

Zhang, Xi; Yi, Yueneng; Qi, Jianping; Lu, Yi; Tian, Zhiqiang; Xie, Yunchang; Yuan, Hailong; Wu, Wei

2013-08-16

It is very important to enhance the absorption simultaneously while designing controlled release delivery systems for poorly water-soluble and poorly permeable drugs (BCS IV). In this study, controlled release of cyclosporine (CyA) was achieved by the osmotic release strategy taking advantage of the absorption-enhancing capacity of self-nanoemulsifying drug delivery systems (SNEDDSs). The liquid SNEDDS consisting of Labrafil M 1944CS, Transcutol P and Cremophor EL was absorbed by the osmotic tablet core excipients (sucrose, lactose monohydrate, polyethylene oxide, and partly pregelatinized starch) and then transformed into osmotic tablets. Near zero-order release could be achieved for CyA-loaded nanoemulsions reconstituted from the SNEDDS. In general, the influencing factor study indicated that the release rate increased with increase of inner osmotic pressure, ratio of osmotic agent to suspending agent, content of pore-forming agent, and size of release orifice, whereas the thickness of the membrane impeded the release of CyA nanoemulsion. Pharmacokinetic study showed steady blood CyA profiles with prolonged Tmax and MRT, and significantly reduced Cmax for self-nanoemulsifying osmotic pump tablet (SNEOPT) in comparison with highly fluctuating profiles of the core tablet and Sandimmune Neoral(®). However, similar oral bioavailability was observed for either controlled release or non-controlled release formulations. It was concluded that simultaneous controlling on CyA release and absorption-enhancing had been achieved by a combination of osmotic tablet and SNEDDS. Copyright © 2013 Elsevier B.V. All rights reserved.

Complement-induced histamine release from human basophils. III. Effect of pharmacologic agents.

PubMed

Hook, W A; Siraganian, R P

1977-02-01

Human serum activated with zymosan generates a factor (C5a) that releases histamine from autologous basophils. Previously we have presented evidence that this mechanism for C5a-induced release differs from IgE-mediated reactions. The effect of several pharmacologic agents known to alter IgE-mediated release was studied to determine whether they have a similar action on serum-induced release. Deuterium oxide (D2O), which enhances allergic release, inhibited in a concentration-dependent fashion the serum-induced reaction at incubation temperatures of 25 and 32 degrees C. The colchicine-induced inhibition was not reversed by D2O. Cytochalasin B, which gives a variable enhancement of IgE-mediated release, had a marked enhancing effect on the serum-induced reaction in all subjects tested. The following agents known to inhibit the IgE-mediated reaction also inhibited serum-induced release at 25 degrees C: colchicine, dibutyryl cyclic AMP, aminophylline, isoproterenol, cholera toxin, chlorphenesin, diethylcarbamazine, and 2-deoxy-D-glucose. These results suggest that the serum-induced release is modulated by intracellular cyclic AMP, requires energy, and is enhanced by the disruption of microfilaments. The lack of an effect by D2O would suggest that microtubular stabilization is not required. The data can be interpreted to indicate that IgE- and C5a-mediated reactions diverge at a late stage in the histamine release pathway.

Native range assessment of classical biological control agents: impact of inundative releases as pre-introduction evaluation.

PubMed

Jenner, W H; Mason, P G; Cappuccino, N; Kuhlmann, U

2010-08-01

Diadromus pulchellus Wesmael (Hymenoptera: Ichneumonidae) is a pupal parasitoid under consideration for introduction into Canada for the control of the invasive leek moth, Acrolepiopsis assectella (Zeller) (Lepidoptera: Acrolepiidae). Since study of the parasitoid outside of quarantine was not permitted in Canada at the time of this project, we assessed its efficacy via field trials in its native range in central Europe. This was done by simulating introductory releases that would eventually take place in Canada when a permit for release is obtained. In 2007 and 2008, experimental leek plots were artificially infested with pest larvae to mimic the higher pest densities common in Canada. Based on a preliminary experiment showing that leek moth pupae were suitable for parasitism up to 5-6 days after pupation, D. pulchellus adults were mass-released into the field plots when the first host cocoons were observed. The laboratory-reared agents reproduced successfully in all trials and radically reduced leek moth survival. Taking into account background parasitism caused by naturally occurring D. pulchellus, the released agents parasitized at least 15.8%, 43.9%, 48.1% and 58.8% of the available hosts in the four release trials. When this significant contribution to leek moth mortality is added to previously published life tables, in which pupal parasitism was absent, the total pupal mortality increases from 60.1% to 76.7%. This study demonstrates how field trials involving environmental manipulation in an agent's native range can yield predictions of the agent's field efficacy once introduced into a novel area.

Effects of Styrene-Acrylic Sizing on the Mechanical Properties of Carbon Fiber Thermoplastic Towpregs and Their Composites.

PubMed

Bowman, Sean; Jiang, Qiuran; Memon, Hafeezullah; Qiu, Yiping; Liu, Wanshuang; Wei, Yi

2018-03-01

Thermoplastic towpregs are convenient and scalable raw materials for the fabrication of continuous fiber-reinforced thermoplastic matrix composites. In this paper, the potential to employ epoxy and styrene-acrylic sizing agents was evaluated for the making of carbon fiber thermoplastic towpregs via a powder-coating method. The protective effects and thermal stability of these sizing agents were investigated by single fiber tensile test and differential scanning calorimetry (DSC) measurement. The results indicate that the epoxy sizing agent provides better protection to carbon fibers, but it cannot be used for thermoplastic towpreg processing due to its poor chemical stability at high temperature. The bending rigidity of the tows and towpregs with two styrene-acrylic sizing agents was measured by cantilever and Kawabata methods. The styrene-acrylic sized towpregs show low torque values, and are suitable for further processing, such as weaving, preforming, and winding. Finally, composite panels were fabricated directly from the towpregs by hot compression molding. Both of the composite panels show superior flexural strength (>400 MPa), flexural modulus (>63 GPa), and interlaminar shear strength (>27 MPa), indicating the applicability of these two styrene-acrylic sizing agents for carbon fiber thermoplastic towpregs.

Development of a novel drug release system, time-controlled explosion system (TES). I. Concept and design.

PubMed

Ueda, S; Hata, T; Asakura, S; Yamaguchi, H; Kotani, M; Ueda, Y

1994-01-01

A novel controlled drug release system. Time-Controlled Explosion System (TES) has been developed. TES has a four-layered spherical structure, which consists of core, drug, swelling agent and water insoluble polymer membrane. TES is characterized by a rapid drug release with a precisely programmed lag time; i.e. expansion of the swelling agent by water penetrating through the outer membrane, destruction of the membrane by stress due to swelling force and subsequent rapid drug release. For establishing the concept and development strategy, TES was designed using metoprolol and polystyrene balls (size: 3.2 mm in diameter) as a model drug and core particles. Among the polymers screened, low-substituted hydroxypropylcellulose (L-HPC) and ethylcellulose (EC) were selected for a swelling agent and an outer water insoluble membrane, respectively. The release profiles of metoprolol from the system were not affected by the pH of the dissolution media. Lag time was controlled by the thickness of the outer EC membrane; thus, a combination of TES particles possessing different lag times could offer any desired release profile of the model compound, metoprolol.

Replication of the nano-scale mold fabricated with focused ion beam

NASA Astrophysics Data System (ADS)

Gao, J. X.; Chan-Park, M. B.; Xie, D. Z.; Ngoi, Bryan K. A.

2004-12-01

Silicon mold fabricated with Focused Ion Beam lithography (FIB) was used to make silicone elastomer molds. The silicon mold is composed of lattice of holes which the diameter and depth are about 200 nm and 60 nm, respectively. The silicone elastomer material was then used to replicate slavery mold. Our study show the replication process with the elastomer mold had been performed successfully and the diameter of humps on the elastomer mold is near to that of holes on the master mold. But the height of humps in the elastomer mold is only 42 nm and it is different from the depth of holes in the master mold.

Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

DOEpatents

Battiste, Richard L.

2007-12-25

Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into the mold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with the fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a temperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into the mold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

Allergies, asthma, and molds

MedlinePlus

Reactive airway - mold; Bronchial asthma - mold; Triggers - mold; Allergic rhinitis - pollen ... Things that make allergies or asthma worse are called triggers. Mold is a common trigger. When your asthma or allergies become worse due to mold, you are ...

Enhancement of Antiviral Agents Through the Use of Controlled-Release Technology.

DTIC Science & Technology

DL-lactide-co-glycolide) to be used as the polymeric excipients in the microencapsulation work. In addition, we have actively pursued development and testing of poly(I.C) and Je vaccine microcapsule formulations....of this research program are a) To develop a programmed-release delivery system ( microcapsule system) designed to enhance the immunogenic potential of...release microcapsule delivery systems that will enhance the effects of the following immune modulators and antiviral agents: muramyl tripeptide (MTP

Polymer blend compositions and methods of preparation

DOEpatents

Naskar, Amit K.

2016-09-27

A polymer blend material comprising: (i) a first polymer containing hydrogen bond donating groups having at least one hydrogen atom bound to a heteroatom selected from oxygen, nitrogen, and sulfur, or an anionic version of said first polymer wherein at least a portion of hydrogen atoms bound to a heteroatom is absent and replaced with at least one electron pair; (ii) a second polymer containing hydrogen bond accepting groups selected from nitrile, halogen, and ether functional groups; and (iii) at least one modifying agent selected from carbon particles, ether-containing polymers, and Lewis acid compounds; wherein, if said second polymer contains ether functional groups, then said at least one modifying agent is selected from carbon particles and Lewis acid compounds. Methods for producing the polymer blend, molded forms thereof, and articles thereof, are also described.

Liquid-solid phase transition alloy as reversible and rapid molding bone cement.

PubMed

Yi, Liting; Jin, Chao; Wang, Lei; Liu, Jing

2014-12-01

Acrylic bone cement has been an essential non-metallic implant used as fixing agent in the cemented total joint arthroplasty (THA). However, the currently available materials based mainly on polymethylmethacrylate (PMMA) still encounter certain limitations, such as time-consuming polymerization, thermal and chemical necrosis and troublesome revision procedure. Here from an alternative way, we proposed for the first time to adopt the injectable alloy cement to address such tough issues through introducing its unique liquid-solid phase transition mechanism. A typical cement along this way is thus made of an alloy Bi/In/Sn/Zn with a specifically designed low melting point 57.5 °C, which enables its rapid molding into various desired shapes with high plasticity and ultimate metallic behaviors. The fundamental characteristics including the mechanical strength, biocompatibility and phase transition-induced thermal effects have been clarified to demonstrate the importance of such alloy as unconventional cement with favorable merits. In addition, we also disclosed its advantage as an excellent contrast agent for radiation imaging on the bone interior structure which is highly beneficial for guiding the surgery and monitoring the therapeutic effects. Particularly, the proposed alloy cement with reversible phase transition feature significantly simplifies the revision of the cement and prosthesis. This study opens the way for employing the injectable alloy materials as reversible bone cement to fulfill diverse clinical needs in the coming time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of Rhodosporidium fluviale as biocontrol agent against Botrytis cinerea on apple fruit.

PubMed

Sansone, G; Lambrese, Y; Calvente, V; Fernández, G; Benuzzi, D; Sanz Ferramola, M

2018-05-01

The aim of the present work was to evaluate the ability of the native yeast Rhodosporidium fluviale to control Botrytis cinerea on apple fruit and to study the possible mechanisms of action with the goal of improving the control of gray mold. For this, the influence of application time of the yeast was studied simulating preventive and curative effects. Also, the effect of nonviable cells of the yeast in the biocontrol was assessed. According to the results obtained, the following mechanisms of action of R. fluviale could be proposed: 1- competition for space, 2- direct interaction between antagonist and pathogen, 3- induction of β-1,3-glucanase in apple tissue, 4- Probable production of glucanase in the apple wounds and 5- antifungal action of cellular components, probably chitin, present in the wall of yeast cells that could be the explanation for the activity of nonviable cells. Significance and Impact of the Study: Botrytis cinerea Pers: Fr, which causes gray mold of fruits and vegetables around the world, is difficult to control successfully because it is genetically variable and rapidly develops resistance to the chemicals commonly used for its control. This study is a contribution to the biocontrol of this phytopathogen fungus. The evaluation of the native yeast Rhodosporidium fluviale as biocontrol agent and the elucidation of possible mechanisms of action, including the participation of nonviable cells of this yeast, have not been reported up to date. © 2018 The Society for Applied Microbiology.

In Vitro Activity of Manuka Honey and Polyhexamethylene Biguanide on Filamentous Fungi and Toxicity to Human Cell Lines

PubMed Central

Yabes, Joseph M.; White, Brian K.; Murray, Clinton K.; Sanchez, Carlos J.; Mende, Katrin; Beckius, Miriam L.; Zera, Wendy C.; Wenke, Joseph C.; Akers, Kevin S.

2016-01-01

Soft-tissue invasive fungal infections are increasingly recognized as significant entities directly contributing to morbidity and mortality. They complicate clinical care, requiring aggressive surgical debridement and systemic antifungal therapy. To evaluate new topical approaches to therapy, we examined the antifungal activity and cytotoxicity of Manuka Honey (MH) and polyhexamethylene biguanide (PHMB). The activities of multiple concentrations of MH (40%, 60%, 80%) and PHMB (0.01%, 0.04%, 0.1%) against 13 clinical mold isolates were evaluated using a time-kill assay between 5 min and 24 h. Concentrations were selected to represent current clinical use. Cell viability was examined in parallel for human epidermal keratinocytes, dermal fibroblasts and osteoblasts, allowing determination of the 50% viability (LD50) concentration. Antifungal activity of both agents correlated more closely with exposure time than concentration. Exophiala and Fusarium growth was completely suppressed at 5 min for all PHMB concentrations, and at 12 and 6 h, respectively, for all MH concentrations. Only Lichtheimia had persistent growth to both agents at 24 h. Viability assays displayed concentration-and time-dependent toxicity for PHMB. For MH, exposure time predicted cytotoxicity only when all cell types were analyzed in aggregate. This study demonstrates that MH and PHMB possess primarily time-dependent antifungal activity, but also exert in vitro toxicity on human cells which may limit clinical use. Further research is needed to determine ideal treatment strategies to optimize antifungal activity against molds while limiting cytotoxicity against host tissues in vivo. PMID:27601610

Prompt remediation of water intrusion corrects the resultant mold contamination in a home.

PubMed

Rockwell, William

2005-01-01

More patients are turning to their allergists with symptoms compatible with allergic rhinitis, allergic sinusitis, and/or bronchial asthma after exposure to mold-contaminated indoor environments. These patients often seek guidance from their allergists in the remediation of the contaminated home or office. The aim of this study was to determine baseline mold spore counts for noncontaminated homes and report a successful mold remediation in one mold-contaminated home. Indoor air quality was tested using volumetric spore counts in 50 homes where homeowners reported no mold-related health problems and in one mold-contaminated home that was remediated. The health of the occupant of the mold-contaminated home also was assessed. Indoor volumetric mold spore counts ranged from 300 to 1200 spores/m3 in the baseline homes. For the successful remediation, the mold counts started at 300 spores/m3, increased to 2800 spores/m3 at the height of the mold contamination, and then fell to 800 spores/m3 after remediation. The occupant's allergic symptoms ceased on complete remediation of the home. Indoor volumetric mold counts taken with the Allergenco MK-3 can reveal a potential indoor mold contamination, with counts above 1000 spores/m3 suggesting indoor mold contamination. Once the presence of indoor mold growth is found, a prompt and thorough remediation can bring mold levels back to near-baseline level and minimize negative health effects for occupants.

Transferability of glass lens molding

NASA Astrophysics Data System (ADS)

Katsuki, Masahide

2006-02-01

Sphere lenses have been used for long time. But it is well known that sphere lenses theoretically have spherical aberration, coma and so on. And, aspheric lenses attract attention recently. Plastic lenses are molded easily with injection machines, and are relatively low cost. They are suitable for mass production. On the other hand, glass lenses have several excellent features such as high refractive index, heat resistance and so on. Many aspheric glass lenses came to be used for the latest digital camera and mobile phone camera module. It is very difficult to produce aspheric glass lenses by conventional process of curve generating and polishing. For the solution of this problem, Glass Molding Machine was developed and is spreading through the market. High precision mold is necessary to mold glass lenses with Glass Molding Machine. The mold core is ground or turned by high precision NC aspheric generator. To obtain higher transferability of the mold core, the function of the molding machine and the conditions of molding are very important. But because of high molding temperature, there are factors of thermal expansion and contraction of the mold and glass material. And it is hard to avoid the factors. In this session, I introduce following items. [1] Technology of glass molding and the machine is introduced. [2] The transferability of glass molding is analyzed with some data of glass lenses molded. [3] Compensation of molding shape error is discussed with examples.

Mold Allergy

MedlinePlus

... Home ▸ Conditions & Treatments ▸ Allergies ▸ Mold Allergy Share | Mold Allergy Overview Symptoms & Diagnosis Treatment & Management Mold Allergy Overview Molds are tiny fungi whose spores float ...

Risk assessment and stakeholder perceptions in novel biological control agent release: YST as a case study

USDA-ARS?s Scientific Manuscript database

The objectives of risk assessment are to learn about whether a candidate agent would be safe to use in the environment where release is planned, and to present such information in a clear, understandable format to regulators, stakeholders, and the public. Plant pathogens evaluated for biological co...

21 CFR 178.3860 - Release agents.

Code of Federal Regulations, 2012 CFR

2012-04-01

... bran wax For use only in plastics intended for contact with dry foods identified as Type VIII in table... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Release agents. 178.3860 Section 178.3860 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 178.3860 - Release agents.

Code of Federal Regulations, 2013 CFR

2013-04-01

... bran wax For use only in plastics intended for contact with dry foods identified as Type VIII in table... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Release agents. 178.3860 Section 178.3860 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 178.3860 - Release agents.

Code of Federal Regulations, 2014 CFR

2014-04-01

... centimeter (1.29 milligrams per square inch) of backing. Rice bran wax For use only in plastics intended for... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Release agents. 178.3860 Section 178.3860 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) INDIRECT FOOD...

Minimum threshold for establishment and dispersal of Lilioceris cheni (Coleoptera: Chrysomelide): a biological control agent of Dioscorea bulbifera

USDA-ARS?s Scientific Manuscript database

The successful establishment or failure of a new population is often attributed to propagule pressure, the combination of the number of independent introduction events, and the number of individuals released at each event. Design of optimal release strategies for biological control agents benefits f...

Effect of cross sectional geometry on PDMS micro peristaltic pump performance: comparison of SU-8 replica molding vs. micro injection molding.

PubMed

Graf, Neil J; Bowser, Michael T

2013-10-07

Two different fabrication methods were employed to fabricate micropumps with different cross-sectional channel geometries. The first was to fabricate rectangular cross-sectional microchannel geometries using the well known fabrication method of replica molding (REM). The second, and far less utilized fabrication technique, was to create microchannel molds using an in-house fabricated handheld micro injection molding apparatus. The injection mold apparatus was designed for use with elastomeric room temperature vulcanization (RTV) polymers, as opposed to most other injection molding machines, which are designed for use with thermoplastic polymers. The injection mold's bottom plate was used as a microchannel molding template. The molding template was created by threading a small-diameter wire (150 μm or less) through the injection mold's bottom plate, with subsequent adhesion and smoothing of a thin piece of aluminum foil over the wire-raised injection mold template. When molded against, the template produced a rounded/Gaussian-shaped PDMS microchannel. The design of the injection mold will be presented, along with a direct comparison for micropump performance metrics such as flow rate, valving characteristics, and maximum backpressures attainable for each of the respective micropump channel geometries.

Interaction of the pathogenic mold Aspergillus fumigatus with lung epithelial cells

PubMed Central

Osherov, Nir

2012-01-01

Aspergillus fumigatus is an opportunistic environmental mold that can cause severe allergic responses in atopic individuals and poses a life-threatening risk for severely immunocompromised patients. Infection is caused by inhalation of fungal spores (conidia) into the lungs. The initial point of contact between the fungus and the host is a monolayer of lung epithelial cells. Understanding how these cells react to fungal contact is crucial to elucidating the pathobiology of Aspergillus-related disease states. The experimental systems, both in vitro and in vivo, used to study these interactions, are described. Distinction is made between bronchial and alveolar epithelial cells. The experimental findings suggest that lung epithelial cells are more than just “innocent bystanders” or a purely physical barrier against infection. They can be better described as an active extension of our innate immune system, operating as a surveillance mechanism that can specifically identify fungal spores and activate an offensive response to block infection. This response includes the internalization of adherent conidia and the release of cytokines, antimicrobial peptides, and reactive oxygen species. In the case of allergy, lung epithelial cells can dampen an over-reactive immune response by releasing anti-inflammatory compounds such as kinurenine. This review summarizes our current knowledge regarding the interaction of A. fumigatus with lung epithelial cells. A better understanding of the interactions between A. fumigatus and lung epithelial cells has therapeutic implications, as stimulation or inhibition of the epithelial response may alter disease outcome. PMID:23055997

Sustained Release of Lidocaine from Solvent-Free Biodegradable Poly[(d,l)-Lactide-co-Glycolide] (PLGA): In Vitro and In Vivo Study.

PubMed

Kau, Yi-Chuan; Liao, Chia-Chih; Chen, Ying-Chi; Liu, Shih-Jung

2014-09-16

Local anesthetics are commonly used for pain relief by regional nerve blocking. In this study, we fabricated solvent-free biodegradable pellets to extend the duration of lidocaine release without any significant local or systemic toxicity levels. To manufacture the pellets, poly[(d,l)-lactide-co-glycolide] (PLGA) was first pre-mixed with lidocaine powder into different ratios. The powder mixture was then compressed with a mold (diameter of 1, 5, 8 or 10 mm) and sintered at 65 °C to form pellets. The in vitro release study showed that the lidocaine/PLGA pellets exhibited a tri-phase release behavior (a burst, a diffusion-controlled release and a degradation-dominated release) and reached completion around day 28. Scanning electron microscope (SEM) photos show that small channels could be found on the surfaces of the pellets on day 2. Furthermore, the polymer matrix swelled and fell apart on day 7, while the pellets became viscous after 10 days of in vitro elution. Perineural administration of the lidocaine/PLGA pellets produced anti-hypersensitivity effects lasting for at least 24 h in rats, significant when compared to the control group (a pure PLGA was pellet administered). In addition, no inflammation was detected within the nerve and in the neighboring muscle by histopathology.

53. PRODUCTION MOLDS. THESE MOLDS ARE COPIES OF THE ORIGINAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

53. PRODUCTION MOLDS. THESE MOLDS ARE COPIES OF THE ORIGINAL MOLDS IN THE MORAVIAN POTTERY AND TILE WORKS COLLECTION, AND ARE USED TO PRESS TILES. THE FACTORY KEEPS TEN PRODUCTION MOLDS FOR EACH IMAGE. THE ORIGINAL MOLDS ARE NOT USED IN PRODUCTION. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

Saliva secretory IgA antibodies against molds and mycotoxins in patients exposed to toxigenic fungi.

PubMed

Vojdani, Aristo; Kashanian, Albert; Vojdani, Elroy; Campbell, Andrew W

2003-11-01

Upper respiratory exposure to different environmental antigens results first in the activation of mucosal immunity and production of IgA antibodies in different secretions including saliva. Despite this there is no study, which addresses secretory antibodies against molds and mycotoxins. The purpose of this study was to evaluate mold-specific salivary IgA in individuals exposed to molds and mycotoxins in a water-damaged building environment. Saliva IgA antibody levels against seven different molds and two mycotoxins were studied in 40 patients exposed to molds and in 40 control subjects. Mold-exposed patients showed significantly higher levels of salivary IgA antibodies against one or more mold species. A majority of patients with high IgA antibodies against molds exhibited elevation in salivary IgA against mycotoxins, as well. These IgA antibodies against molds and mycotoxins are specific, since using molds and mycotoxins in immune absorption could reduce antibody levels, significantly. Detection of high counts of molds in water-damaged buildings, strongly suggests the existence of a reservoir of mold spores in the environment. This viable microbial activity with specific mold and mycotoxin IgA in saliva may assist in the diagnosis of mold exposure. Whether mold and mycotoxin specific IgA antibodies detected in saliva are indicative of the role of IgA antibodies in the late phase of type-1 hypersensitivity reaction or in type-2 and type-3 delayed sensitivities is a matter that warrants further investigation.

Identification of a consistent polyene component of purple pigment in diseased sclerites of Caribbean corals across region, species, and insult agent.

PubMed

Fetterolf, Monty L; Leverette, Chad L; Perez, Christopher; Smith, Garriet W

2017-10-05

Gorgonians respond to insult (damage and disease) by producing sclerites containing a purple pigment as opposed to the normal white sclerites. Raman microscopy is used to study the purple areas of three species of diseased coral, Gorgonia ventalina, Pseudoplexaura porosa, and Eunicea laciniata obtained from Puerto Rico. These spectra were compared to Gorgonia ventalina samples previously reported that were obtained from San Salvador, Bahamas. Spectra from two samples of G. ventalina that had been infected by different agents, Aspergillus sydowii and a slime mold, were also obtained. The results indicate that the purple compounds (polyenes) generated by the coral in response to infection are similar regardless of region from which the coral were harvested, of species of coral, and of the infective agent. A discussion of the Raman spectra of G. ventalina and the other coral species is presented. Copyright © 2017 Elsevier B.V. All rights reserved.

Controlled porosity osmotic pump-based controlled release systems of pseudoephedrine. I. Cellulose acetate as a semipermeable membrane.

PubMed

Makhija, Sapna N; Vavia, Pradeep R

2003-04-14

A controlled porosity osmotic pump-based drug delivery system has been described in this study. Unlike the elementary osmotic pump (EOP) which consists of an osmotic core with the drug surrounded by a semipermeable membrane drilled with a delivery orifice, controlled porosity of the membrane is accomplished by the use of different channeling agents in the coating. The usual dose of pseudoephedrine is 60 mg to be taken three or four times daily. It has a short plasma half life of 5-8 h. Hence, pseudoephedrine was chosen as a model drug with an aim to develop a controlled release system for a period of 12 h. Sodium bicarbonate was used as the osmogent. The effect of different ratios of drug:osmogent on the in-vitro release was studied. Cellulose acetate (CA) was used as the semipermeable membrane. Different channeling agents tried were diethylphthalate (DEP), dibutylphthalate (DBP), dibutylsebacate (DBS) and polyethyleneglycol 400 (PEG 400). The effect of polymer loading on in-vitro drug release was studied. It was found that drug release rate increased with the amount of osmogent due to the increased water uptake, and hence increased driving force for drug release. This could be retarded by the proper choice of channeling agent in order to achieve the desired zero order release profile. Also the lag time seen with tablets coated using diethylphthalate as channeling agent was reduced by using a hydrophilic plasticizer like polyethyleneglycol 400 in combination with diethylphthalate. This system was found to deliver pseudoephedrine at a zero order rate for 12 h. The effect of pH on drug release was also studied. The optimized formulations were subjected to stability studies as per ICH guidelines at different temperature and humidity conditions.

Resin film infusion mold tooling and molding method

NASA Technical Reports Server (NTRS)

Burgess, Roger (Inventor); Grossheim, Brian (Inventor); Mouradian, Karbis (Inventor); Thrash, Patrick J. (Inventor)

1999-01-01

A mold apparatus and method for resin film infusion molding including an outer mold tool having a facing sheet adapted to support a resin film and preform assembly. The facing sheet includes attachment features extending therefrom. An inner mold tool is positioned on the facing sheet to enclose the resin film and preform assembly for resin film infusion molding. The inner mold tool includes a plurality of mandrels positioned for engagement with the resin film and preform assembly. Each mandrel includes a slot formed therein. A plurality of locating bars cooperate with the slots and with the attachment features for locating the mandrels longitudinally on the outer mold tool.

Foundations of “new” social science: Institutional legitimacy from philosophy, complexity science, postmodernism, and agent-based modeling

PubMed Central

Henrickson, Leslie; McKelvey, Bill

2002-01-01

Since the death of positivism in the 1970s, philosophers have turned their attention to scientific realism, evolutionary epistemology, and the Semantic Conception of Theories. Building on these trends, Campbellian Realism allows social scientists to accept real-world phenomena as criterion variables against which theories may be tested without denying the reality of individual interpretation and social construction. The Semantic Conception reduces the importance of axioms, but reaffirms the role of models and experiments. Philosophers now see models as “autonomous agents” that exert independent influence on the development of a science, in addition to theory and data. The inappropriate molding effects of math models on social behavior modeling are noted. Complexity science offers a “new” normal science epistemology focusing on order creation by self-organizing heterogeneous agents and agent-based models. The more responsible core of postmodernism builds on the idea that agents operate in a constantly changing web of interconnections among other agents. The connectionist agent-based models of complexity science draw on the same conception of social ontology as do postmodernists. These recent developments combine to provide foundations for a “new” social science centered on formal modeling not requiring the mathematical assumptions of agent homogeneity and equilibrium conditions. They give this “new” social science legitimacy in scientific circles that current social science approaches lack. PMID:12011408

Improved compression molding process

NASA Technical Reports Server (NTRS)

Heier, W. C.

1967-01-01

Modified compression molding process produces plastic molding compounds that are strong, homogeneous, free of residual stresses, and have improved ablative characteristics. The conventional method is modified by applying a vacuum to the mold during the molding cycle, using a volatile sink, and exercising precise control of the mold closure limits.

Mold and Health

EPA Pesticide Factsheets

Molds have the potential to cause health problems. Molds produce allergens (substances that can cause allergic reactions) and irritants. Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals.

MOLD-SPECIFIC QUANTITATIVE PCR: THE EMERGING STANDARD IN MOLD ANALYSIS

EPA Science Inventory

Molds can cause health problems like infections and allergies, destroy crops, and contaminate our food or pharmaceuticals. We can't avoid molds. Molds are essential players in the biological processes on earth, but we can now identify and quantify the molds that will be most pr...

Traditional Mold Analysis Compared to a DNA-based Method of Mold Analysis with Applications in Asthmatics' Homes

EPA Science Inventory

Traditional environmental mold analysis is based-on microscopic observations and counting of mold structures collected from the air on a sticky surface or culturing of molds on growth media for identification and quantification. A DNA-based method of mold analysis called mol...

92. PRODUCTION MOLDS. THESE MOLDS ARE COPIES OF THE ORIGINAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

92. PRODUCTION MOLDS. THESE MOLDS ARE COPIES OF THE ORIGINAL MOLDS IN THE MORAVIAN POTTERY AND TILE WORKS COLLECTION, AND ARE USED TO PRESS TILES. THE FACTORY KEEPS TEN PRODUCTION MOLDS FOR EACH IMAGE. THE ORIGINAL MOLDS ARE NOT USED IN PRODUCTION. SAME VIEW AS PA-107-53. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

Entomopathogenic Fungi as Dual Control Agents against Both the Pest Myzus persicae and Phytopathogen Botrytis cinerea

PubMed Central

Yun, Hwi-Geon; Kim, Dong-Jun; Gwak, Won-Seok; Shin, Tae-Young

2017-01-01

The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection. PMID:29138624

Entomopathogenic Fungi as Dual Control Agents against Both the Pest Myzus persicae and Phytopathogen Botrytis cinerea.

PubMed

Yun, Hwi-Geon; Kim, Dong-Jun; Gwak, Won-Seok; Shin, Tae-Young; Woo, Soo-Dong

2017-09-01

The green peach aphid ( Myzus persicae ), a plant pest, and gray mold disease, caused by Botrytis cinerea , affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae . Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.

Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

DOEpatents

Battiste, Richard L

2013-12-31

Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into th emold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with a fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a termperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into th emold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

Releasing biocontrol agents: Risk assessment and overdue reform

Treesearch

Bob Peterson; Sharlene Sing

2007-01-01

Although the need for universally instituting formal risk assessment (RA) in the screening and approval process for non-native biological control (BC) agent releases has been widely acknowledged for the past several years, little seems to have been accomplished in terms of codifying this practice within a regulatory framework. Given the low success rate of classical BC...

Synthetic Quorum Sensing and Induced Aggregation in Model Microcapsule Colonies with Repressilator Feedback

NASA Astrophysics Data System (ADS)

Shum, Henry; Yashin, Victor; Balazs, Anna

We model a system of synthetic microcapsules that communicate chemically by releasing nanoparticles or signaling molecules. These signaling species bind to receptors on the shells of capsules and modulate the target shell's permeability, thereby controlling nanoparticle release from the target capsule. Using the repressilator regulatory network motif, whereby three species suppress the production of the next in a cyclic fashion, we show that large amplitude oscillations in nanoparticle release can emerge when many capsules are close together. This exemplifies quorum sensing, which is the ability of cells to gauge their population density and collectively initiate a new behavior once a critical density is reached. We present a physically realizable model in which the oscillations exhibited in crowded populations induce aggregation of the microcapsules, mimicking complex biological behavior of the slime mold Dictyostelium discoideum with only simple, synthetic components. We also show that the clusters can be dispersed and reformed repeatedly and controllably by addition of chemical stimuli, demonstrating possible applications in creating reconfigurable or programmable materials.

Preparation of an Environment-friendly Biochar Fertilizer

NASA Astrophysics Data System (ADS)

Zhong, Xuan; Wang, Mingfeng; Jiang, Enchen

2018-01-01

Combining biochar with urea can not only enhance the release efficiency of urea, but also improve the soil environment thus promoting the growth of plant. However, the low mechanical strength and overuse of binder have limited the improvement of the biochar fertilizer (BF). An novel BF was prepared by putting the mixture of biochar and urea into a molding tube with diameter of 6-12mm and heating at 155°C. Molten urea (155°C) was used as binder to combine with biochar in a way of heterogeneous permeation & integration. The maximum compressive strengh of BF samples with different diameter are in the range of 46.34-108.54N, much larger to that of pure urea (12.1N). The leaching experiments show that only 19.5%-33.5% of BF samples released at the first day, exhibiting a slow-release property. Therefore, our study has demonstrated the potential of this novel BF for improving the effectiveness of fertilizer.

Curbing indoor mold growth with mold inhibitors

Treesearch

Carol A. Clausen; Vina W. Yang

2004-01-01

Environmentally acceptable mold inhibitors are needed to curb the growth of mold fungi in woodframe housing when moisture management measures fail. Excess indoor moisture can lead to rapid mold establishment which, in turn, can have deleterious affects on indoor air quality. Compounds with known mold inhibitory properties and low mammalian toxicity, such as food...

Indoor Molds and Respiratory Hypersensitivity: A Comparison of Selected Molds and House Dust Mite Induced Responses in a Mouse Model**

EPA Science Inventory

Molds are ubiquitous in the environment and exposures to molds contribute to various human diseases. Damp/moldy environments have been associated with asthma exacerbation, but mold's role in allergic asthma induction is less clear. The molds selected for these studies are commonl...

Occupational exposure to airborne asbestos from phenolic molding material (Bakelite) during sanding, drilling, and related activities.

PubMed

Mowat, Fionna; Bono, Michael; Lee, R J; Tamburello, Susan; Paustenbach, Dennis

2005-10-01

In this study, a historical phenolic (Bakelite) molding material, BMMA-5353, was tested to determine the airborne concentrations of asbestos fibers released during four different activities (sawing, sanding, drilling, and cleanup of dust generated from these activities). Each activity was performed for 30 min, often in triplicate. The primary objective for testing BMMA-5353 was to quantitatively determine the airborne concentration of asbestos fibers, if any, in the breathing zone of workers. Uses of this product typically did not include sawing or sanding, but it may have been drilled occasionally. For this reason, only small quantities were sawed, sanded, and drilled in this simulation study. Personal (n = 40), area (n = 80), and background/clearance (n = 88) air samples were collected during each activity and analyzed for total fiber concentrations using phase contrast microscopy (PCM) and, for asbestos fiber counts, transmission electron microscopy (TEM). The raw PCM-total fiber concentrations were adjusted based on TEM analyses that reported the fraction of asbestos fibers, to derive a PCM-asbestos concentration that would enable calculation of an 8-hour time-weighted average (TWA). The estimated 8-hour TWAs ranged from 0.006 to 0.08 fibers per cubic centimeter using a variety of worker exposure scenarios. Therefore, assuming an exposure scenario in which a worker uses power tools to cut and sand products molded from BMMA-5353 and similar products in the manner evaluated in this study, airborne asbestos concentrations should not exceed current or historical occupational exposure limits.

Method to Create Arbitrary Sidewall Geometries in 3-Dimensions Using Liga with a Stochastic Optimization Framework

NASA Technical Reports Server (NTRS)

Eyre, Francis B. (Inventor); Fink, Wolfgang (Inventor)

2011-01-01

Disclosed herein is a method of making a three dimensional mold comprising the steps of providing a mold substrate; exposing the substrate with an electromagnetic radiation source for a period of time sufficient to render the portion of the mold substrate susceptible to a developer to produce a modified mold substrate; and developing the modified mold with one or more developing reagents to remove the portion of the mold substrate rendered susceptible to the developer from the mold substrate, to produce the mold having a desired mold shape, wherein the electromagnetic radiation source has a fixed position, and wherein during the exposing step, the mold substrate is manipulated according to a manipulation algorithm in one or more dimensions relative to the electromagnetic radiation source; and wherein the manipulation algorithm is determined using stochastic optimization computations.

In Vitro Antifungal Susceptibility of Yeast and Mold Phases of Isolates of Dimorphic Fungal Pathogen Emergomyces africanus (Formerly Emmonsia sp.) from HIV-Infected South African Patients.

PubMed

Maphanga, Tsidiso G; Britz, Erika; Zulu, Thokozile G; Mpembe, Ruth S; Naicker, Serisha D; Schwartz, Ilan S; Govender, Nelesh P

2017-06-01

Disseminated emmonsiosis is an important AIDS-related mycosis in South Africa that is caused by Emergomyces africanus , a newly described and renamed dimorphic fungal pathogen. In vitro antifungal susceptibility data can guide management. Identification of invasive clinical isolates was confirmed phenotypically and by sequencing of the internal transcribed spacer region. Yeast and mold phase MICs of fluconazole, voriconazole, itraconazole, posaconazole, caspofungin, anidulafungin, micafungin, and flucytosine were determined with custom-made frozen broth microdilution (BMD) panels in accordance with Clinical and Laboratory Standards Institute recommendations. MICs of amphotericin B, itraconazole, posaconazole, and voriconazole were determined by Etest. Fifty unique E. africanus isolates were tested. The yeast and mold phase geometric mean (GM) BMD and Etest MICs of itraconazole were 0.01 mg/liter. The voriconazole and posaconazole GM BMD MICs were 0.01 mg/liter for both phases, while the GM Etest MICs were 0.001 and 0.002 mg/liter, respectively. The fluconazole GM BMD MICs were 0.18 mg/liter for both phases. The GM Etest MICs of amphotericin B, for the yeast and mold phases were 0.03 and 0.01 mg/liter. The echinocandins and flucytosine had very limited in vitro activity. Treatment and outcome data were available for 37 patients; in a multivariable model including MIC data, only isolation from blood (odds ratio [OR], 8.6; 95% confidence interval [CI], 1.3 to 54.4; P = 0.02) or bone marrow (OR, 12.1; 95% CI, 1.2 to 120.2; P = 0.03) (versus skin biopsy) was associated with death. In vitro susceptibility data support the management of disseminated emmonsiosis with amphotericin B, followed by itraconazole, voriconazole, or posaconazole. Fluconazole was a relatively less potent agent. Copyright © 2017 American Society for Microbiology.

Mold Testing or Sampling

EPA Pesticide Factsheets

In most cases, if visible mold growth is present, sampling is unnecessary. Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building's compliance with federal mold standards.

Method for making an elastomeric member with end pieces

DOEpatents

Hoppie, L.O.; McNinch, J.H. Jr.; Nowell, G.C.

1984-10-23

A molding process is described for molding an elongated elastomeric member with wire mesh sleeves bonded to the ends. A molding preform of elastomeric material is positioned within a seamless mold cylinder, and the open ends of the wire mesh sleeves are mounted to end plug assemblies slidably received into the mold cylinder and positioned against the ends of the preform. A specialized profile is formed into surfaces of the respective end plug assemblies and by heating of the mold, the ends of the elastomeric preform are molded to the profile, as well as bonded to the reinforcing wire mesh sleeves. Vacuum is applied to the interior of the mold to draw outgassing vapors through relief spaces there through. The completed elastomeric member is removed from the mold cylinder by stretching, the consequent reduction in diameter enabling ready separation from the mold cylinder and removal thereof. 9 figs.

High Cost/High Risk Components to Chalcogenide Molded Lens Model: Molding Preforms and Mold Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernacki, Bruce E.

2012-10-05

This brief report contains a critique of two key components of FiveFocal's cost model for glass compression molding of chalcogenide lenses for infrared applications. Molding preforms and mold technology have the greatest influence on the ultimate cost of the product and help determine the volumes needed to select glass molding over conventional single-point diamond turning or grinding and polishing. This brief report highlights key areas of both technologies with recommendations for further study.

Antibacterial and Anti-inflammatory Activities of Ppc-1, Active Principle of the Cellular Slime Mold Polysphondylium pseudo-candidum.

PubMed

Azelmat, Jabrane; Fiorito, Serena; Genovese, Salvatore; Epifano, Francesco; Grenier, Daniel

2015-01-01

The diisopentenyloxy quinolobactin derivative 3-methylbut-2-enyl-4-methoxy-8-[(3-methylbut-2-enyl)oxy] quinoline-2-carboxylate, also named as Ppc-1, has been initially isolated from the fruiting bodies of the cellular slime mold Polysphondylium pseudo-candidum. Given that few data are available in the literature concerning the biological properties of this compound, this study was undertaken to evaluate its antibacterial and anti-inflammatory properties. Ppc-1 exerted antibacterial activity on the Gram negative periodontopathogen Porphyromonas gingivalis, while it had no such effect on the other bacterial species tested. The antibacterial activity of Ppc-1 appeared to result from its ability to permeate the cell membrane. Using the U937-3xκB-LUC human monocytic cell line, Ppc-1 was found to dose-dependently inhibit the lipopolysaccharide-induced NF-κB activation, a signaling pathway that has been associated with inflammatory mediator secretion. In conclusion, Ppc-1, by exhibiting a dual mode of action including antibacterial and anti-inflammatory activities, may represent a promising targeted therapeutic agent for periodontal diseases.

Colloidal isopressing: A new shaping method for ceramic suspensions

NASA Astrophysics Data System (ADS)

Yu, Benjamin Christopher

Colloidal Isopressing is a new processing method for shaping compacts from particulate suspensions. The study of interparticle interactions within a suspension, and their effect on the overall slurry behavior, has led to the prior discovery of a plastic-to-brittle transition in powder compacts formed by pressure filtration. Colloidal Isopressing utilizes this pressure dependent behavior for slurries with a short-range repulsive potential to rapidly transform plastic consolidated bodies into more complex shapes. The first results are presented for aqueous alumina suspensions where electrostatic double layer repulsion is compressed to short interparticle separations by the addition of ammonium chloride. Consolidation at low pressures produces a high relative density slurry that is plastic and can be extruded into a rubber mold. The application of an hydrostatic pressure forces a small amount of liquid into a porous portion of the mold and pushes particles together into a rigid network. As the pressure is released, the newly formed powder compact will partially separate from the lower modulus rubber mold. The body can then be ejected from the mold, dried, and densified to produce the final ceramic component. Colloidal Isopressing has been successfully modeled as a special case of consolidation via pressure filtration. Theoretical analyses have accurately predicted the time required for the rapid transformation from plastic slurry to elastic powder compact. The effects of slurry composition on processing were studied. The electrolyte concentration, powder particle size, slurry pH, and polymer concentration were shown to alter the flow behavior of filter pressed and liquefied compacts. As the free volume of liquid decreased and/or the relative attraction between particles increased, the concentrated slurry became more difficult to process. Finally, drying of compacts formed by Colloidal Isopressing did not result in any shrinkage during drying, thus allowing for very rapid heating rates to be used. In fact, the drying, burnout, and densification could be combined into one step, with final densities approaching the theoretical limit.

Exploring the problem of mold growth and the efficacy of various mold inhibitor methods during moisture sorption isotherm measurements.

PubMed

Yu, X; Martin, S E; Schmidt, S J

2008-03-01

Mold growth is a common problem during the equilibration of food materials at high relative humidity values using the standard saturated salt slurry method. Exposing samples to toluene vapor and mixing samples with mold inhibitor chemicals are suggested methods for preventing mold growth while obtaining isotherms. However, no published research was found that examined the effect of mold growth on isotherm performance or the efficacy of various mold inhibitor methods, including their possible effect on the physicochemical properties of food materials. Therefore, the objectives of this study were to (1) explore the effect of mold growth on isotherm performance in a range of food materials, (2) investigate the effectiveness of 4 mold inhibitor methods, irradiation, 2 chemical inhibitors (potassium sorbate and sodium acetate), and toluene vapor, on mold growth on dent corn starch inoculated with A. niger, and (3) examine the effect of mold inhibitor methods on the physicochemical properties of dent corn starch, including isotherm performance, pasting properties, gelatinization temperature, and enthalpy. Mold growth was found to affect starch isotherm performance by contributing to weight changes during sample equilibration. Among the 4 mold inhibitor methods tested, irradiation and toluene vapor were found to be the most effective for inhibiting growth of A. niger on dent cornstarch. However, both methods exhibited a significant impact on the starches' physiochemical properties, suggesting the need to probe the efficacy of other mold inhibitor methods and explore the use of new rapid isotherm instruments, which hamper mold growth by significantly decreasing measurement time.

40 CFR Table 3 to Subpart Wwww of... - Organic HAP Emissions Limits for Existing Open Molding Sources, New Open Molding Sources Emitting...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Existing Open Molding Sources, New Open Molding Sources Emitting Less Than 100 TPY of HAP, and New and... CATEGORIES National Emissions Standards for Hazardous Air Pollutants: Reinforced Plastic Composites... Existing Open Molding Sources, New Open Molding Sources Emitting Less Than 100 TPY of HAP, and New and...

21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG ADMINISTRATION..., sheep's milk blue-mold, and blue-mold cheese from sheep's milk. (a) Description. (1) Roquefort cheese...

21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG ADMINISTRATION..., sheep's milk blue-mold, and blue-mold cheese from sheep's milk. (a) Description. (1) Roquefort cheese...

21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG ADMINISTRATION..., sheep's milk blue-mold, and blue-mold cheese from sheep's milk. (a) Description. (1) Roquefort cheese...

The reflectivity, wettability and scratch durability of microsurface features molded in the injection molding process using a dynamic tool tempering system

NASA Astrophysics Data System (ADS)

Kuhn, Sascha; Burr, August; Kübler, Michael; Deckert, Matthias; Bleesen, Christoph

2011-02-01

In this paper the replication qualities of periodically and randomly arranged micro-features molded in the injection molding process and their effects on surface properties are studied. The features are molded in PC, PMMA and PP at different mold wall temperatures in order to point out the necessity and profitability of a variotherm mold wall temperature control system. A one-dimensional heat conduction model is proposed to predict the cycle times of the variotherm injection molding processes. With regard to these processes, the molding results are compared to the molded surface feature heights using an atomic force microscope. In addition, the effects of the molded surface features on macroscopic surfaces are characterized in terms of light reflection using a spectrometer and in terms of water wettability by measuring the static contact angle. Furthermore, due to the sensitivity of the surface features on the molded parts, their durability is compared in a scratch test with a diamond tip. This leads to successful implementation in applications in which the optical appearance, in terms of gloss and reflection, and the water repellence, in terms of drag flow and adhesion, are of importance.

Implications of diamond-turned versus diamond-ground mold fabrication techniques on precision-molded optics

NASA Astrophysics Data System (ADS)

Mertus, Lou; Symmons, Alan

2012-10-01

In recent years, the trend within the molded optics community has been an overall advancement in the capability to diamond grind molds using a variety of grinding techniques. Improvements in grinding equipment, materials and tooling have enabled higher quality ceramic and carbide molds and thereby lenses. Diamond turned molds from ductile metals are still used prevalently throughout the molding industry. Each technology presents a unique set of advantages and disadvantages whether used for precision injection molding of plastic optics or precision glass molding. This paper reviews the manufacturing techniques for each approach and applicable molding process. The advantages and disadvantages of each are compared and analyzed. The subtle differences that exist in optics molded from each technique and the impact they have on the performance in various applications is reviewed. Differences stemming from tooling material properties, material-specific minor defects, as well as cutting and grinding process-induced artifacts are described in detail as well as their influence on the roughness, waviness, and form errors present on the molded surface. A comparison with results between similar surfaces for both diamond grinding and diamond turning is presented.

Transition Metal Free C-N Bond Forming Dearomatizations and Aryl C-H Aminations by in Situ Release of a Hydroxylamine-Based Aminating Agent.

PubMed

Farndon, Joshua J; Ma, Xiaofeng; Bower, John F

2017-10-11

We outline a simple protocol that accesses directly unprotected secondary amines by intramolecular C-N bond forming dearomatization or aryl C-H amination. The method is dependent on the generation of a potent electrophilic aminating agent released by in situ deprotection of O-Ts activated N-Boc hydroxylamines.

Predatory behavior of long-legged flies (Diptera:Dolichopodidae) and their potential negative effects on the parasitoid biological control agent of the Asian citrus psyllid (Hemiptera:Liviidae)

USDA-ARS?s Scientific Manuscript database

Impact of biological control agents such as parasitoids can be improved by determining best times for release when predation pressures will be reduced. Large populations of long-legged predatory flies (Diptera: Dolichopodidae) impose heavy predation pressure on inundative releases of the parasitoid ...

Analytical model for effects of capsule shape on the healing efficiency in self-healing materials

PubMed Central

Li, Songpeng; Chen, Huisu

2017-01-01

The fundamental requirement for the autonomous capsule-based self-healing process to work is that cracks need to reach the capsules and break them such that the healing agent can be released. Ignoring all other aspects, the amount of healing agents released into the crack is essential to obtain a good healing. Meanwhile, from the perspective of the capsule shapes, spherical or elongated capsules (hollow tubes/fibres) are the main morphologies used in capsule-based self-healing materials. The focus of this contribution is the description of the effects of capsule shape on the efficiency of healing agent released in capsule-based self-healing material within the framework of the theory of geometrical probability and integral geometry. Analytical models are developed to characterize the amount of healing agent released per crack area from capsules for an arbitrary crack intersecting with capsules of various shapes in a virtual capsule-based self-healing material. The average crack opening distance is chosen to be a key parameter in defining the healing potential of individual cracks in the models. Furthermore, the accuracy of the developed models was verified by comparison to the data from a published numerical simulation study. PMID:29095862

Sustained release of a novel anti-quorum-sensing agent against oral fungal biofilms.

PubMed

Feldman, Mark; Shenderovich, Julia; Al-Quntar, Abed Al Aziz; Friedman, Michael; Steinberg, Doron

2015-04-01

Thiazolidinedione-8 (S-8) has recently been identified as a potential anti-quorum-sensing/antibiofilm agent against bacteria and fungi. Based on these results, we investigated the possibility of incorporating S-8 in a sustained-release membrane (SRM) to increase its pharmaceutical potential against Candida albicans biofilm. We demonstrated that SRM containing S-8 inhibits fungal biofilm formation in a time-dependent manner for 72 h, due to prolonged release of S-8. Moreover, the SRM effectively delivered the agent in its active form to locations outside the membrane reservoir. In addition, eradication of mature biofilm by the SRM containing S-8 was also significant. Of note, S-8-containing SRM affected the characteristics of mature C. albicans biofilm, such as thickness, exopolysaccharide (EPS) production, and morphogenesis of fungal cells. The concept of using an antibiofilm agent with no antifungal activity incorporated into a sustained-release delivery system is new in medicine and dentistry. This concept of an SRM containing a quorum-sensing quencher with an antibiofilm effect could pave the way for combating oral fungal infectious diseases. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Release of betaine and dexpanthenol from vitamin E modified silicone-hydrogel contact lenses.

PubMed

Hsu, Kuan-Hui; de la Jara, Percy Lazon; Ariyavidana, Amali; Watling, Jason; Holden, Brien; Garrett, Qian; Chauhan, Anuj

2015-03-01

To develop a contact lens system that will control the release of an osmoprotectant and a moisturizing agent with the aim to reduce symptoms of ocular dryness. Profiles of the release of osmoprotectant betaine and moisturizing agent dexpanthenol from senofilcon A and narafilcon B contact lenses were determined in vitro under sink conditions. Both types of lenses were also infused with vitamin E to increase the duration of drug release due to the formation of the vitamin E diffusion barriers in the lenses. The release profiles from vitamin E-infused lenses were compared with those from the control lenses. Both dexpanthenol and betaine are released from commercial silicone hydrogel lenses for only about 10 min. Vitamin E loadings into contact lenses at about 20-23% can increase the release times to about 10 h, which is about 60 times larger compared to the control unmodified lenses. Vitamin E-loaded silicone hydrogel contact lenses released betaine and dexpanthenol in a controlled fashion.

Recent Developments on Microencapsulation for Autonomous Corrosion Protection

NASA Technical Reports Server (NTRS)

Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Fitzpatrick, Lilliana; Jolley, Scott T.; Surma, Jan M.; Pearman, Benjamin P.; Zhang, Xuejun

2014-01-01

This work concerns recent progress in the development of a multifunctional smart coating based on microencapsulation for the autonomous control of corrosion. Microencapsulation allows the incorporation of desired corrosion control functionalities, such as early corrosion detection and inhibition through corrosion controlled release of corrosion indicators and inhibitors, as well as self-healing agent release when mechanical damage occurs.While proof-of-concept results have been reported previously, more recent efforts have been concentrated in technical developments to improve coating compatibility, synthesis procedure scalability, as well as fine tuning the release property of encapsulated active agents.

Measuring the Acoustic Release of a Chemotherapeutic Agent from Folate-Targeted Polymeric Micelles.

PubMed

Abusara, Ayah; Abdel-Hafez, Mamoun; Husseini, Ghaleb

2018-08-01

In this paper, we compare the use of Bayesian filters for the estimation of release and re-encapsulation rates of a chemotherapeutic agent (namely Doxorubicin) from nanocarriers in an acoustically activated drug release system. The study is implemented using an advanced kinetic model that takes into account cavitation events causing the antineoplastic agent's release from polymeric micelles upon exposure to ultrasound. This model is an improvement over the previous representations of acoustic release that used simple zero-, first- and second-order release and re-encapsulation kinetics to study acoustically triggered drug release from polymeric micelles. The new model incorporates drug release and micellar reassembly events caused by cavitation allowing for the controlled release of chemotherapeutics specially and temporally. Different Bayesian estimators are tested for this purpose including Kalman filters (KF), Extended Kalman filters (EKF), Particle filters (PF), and multi-model KF and EKF. Simulated and experimental results are used to verify the performance of the above-mentioned estimators. The proposed methods demonstrate the utility and high-accuracy of using estimation methods in modeling this drug delivery technique. The results show that, in both cases (linear and non-linear dynamics), the modeling errors are expensive but can be minimized using a multi-model approach. In addition, particle filters are more flexible filters that perform reasonably well compared to the other two filters. The study improved the accuracy of the kinetic models used to capture acoustically activated drug release from polymeric micelles, which may in turn help in designing hardware and software capable of precisely controlling the delivered amount of chemotherapeutics to cancerous tissue.

Staged mold for encapsulating hazardous wastes

DOEpatents

Unger, Samuel L.; Telles, Rodney W.; Lubowitz, Hyman R.

1990-01-01

A staged mold for stabilizing hazardous wastes for final disposal by molding an agglomerate of the hazardous wastes and encapsulating the agglomerate. Three stages are employed in the process. In the first stage, a first mold body is positioned on a first mold base, a mixture of the hazardous wastes and a thermosetting plastic is loaded into the mold, the mixture is mechanically compressed, heat is applied to cure the mixture to form a rigid agglomerate, and the first mold body is removed leaving the agglomerate sitting on the first mold base. In the second stage, a clamshell second mold body is positioned around the agglomerate and the first mold base, a powdered thermoplastic resin is poured on top of the agglomerate and in the gap between the sides of the agglomerate and the second mold body, the thermoplastic is compressed, heat is applied to melt the thermoplastic, and the plastic is cooled jacketing the agglomerate on the top and sides. In the third stage, the mold with the jacketed agglomerate is inverted, the first mold base is removed exposing the former bottom of the agglomerate, powdered thermoplastic is poured over the former bottom, the first mold base is replaced to compress the thermoplastic, heat is applied to melt the new thermoplastic and the top part of the jacket on the sides, the plastic is cooled jacketing the bottom and fusing with the jacketing on the sides to complete the seamless encapsulation of the agglomerate.

Staged mold for encapsulating hazardous wastes

DOEpatents

Unger, Samuel L.; Telles, Rodney W.; Lubowitz, Hyman R.

1988-01-01

A staged mold for stabilizing hazardous wastes for final disposal by molding an agglomerate of the hazardous wastes and encapsulating the agglomerate. Three stages are employed in the process. In the first stage, a first mold body is positioned on a first mold base, a mixture of the hazardous wastes and a thermosetting plastic is loaded into the mold, the mixture is mechanically compressed, heat is applied to cure the mixture to form a rigid agglomerate, and the first mold body is removed leaving the agglomerate sitting on the first mold base. In the second stage, a clamshell second mold body is positioned around the agglomerate and the first mold base, a powdered thermoplastic resin is poured on top of the agglomerate and in the gap between the sides of the agglomerate and the second mold body, the thermoplastic is compressed, heat is applied to melt the thermoplastic, and the plastic is cooled jacketing the agglomerate on the top and sides. In the third stage, the mold with the jacketed agglomerate is inverted, the first mold base is removed exposing the former bottom of the agglomerate, powdered thermoplastic is poured over the former bottom, the first mold base is replaced to compress the thermoplastic, heat is applied to melt the new thermoplastic and the top part of the jacket on the sides, the plastic is cooled jacketing the bottom and fusing with the jacketing on the sides to complete the seamless encapsulation of the agglomerate.

Method for encapsulating hazardous wastes using a staged mold

DOEpatents

Unger, Samuel L.; Telles, Rodney W.; Lubowitz, Hyman R.

1989-01-01

A staged mold and method for stabilizing hazardous wastes for final disposal by molding an agglomerate of the hazardous wastes and encapsulating the agglomerate. Three stages are employed in the process. In the first stage, a first mold body is positioned on a first mold base, a mixture of the hazardous wastes and a thermosetting plastic is loaded into the mold, the mixture is mechanically compressed, heat is applied to cure the mixture to form a rigid agglomerate, and the first mold body is removed leaving the agglomerate sitting on the first mold base. In the second stage, a clamshell second mold body is positioned around the agglomerate and the first mold base, a powdered thermoplastic resin is poured on top of the agglomerate and in the gap between the sides of the agglomerate and the second mold body, the thermoplastic is compressed, heat is applied to melt the thermoplastic, and the plastic is cooled jacketing the agglomerate on the top and sides. In the third stage, the mold with the jacketed agglomerate is inverted, the first mold base is removed exposing the former bottom of the agglomerate, powdered thermoplastic is poured over the former bottom, the first mold base is replaced to compress the thermoplastic, heat is applied to melt the new thermoplastic and the top part of the jacket on the sides, the plastic is cooled jacketing the bottom and fusing with the jacketing on the sides to complete the seamless encapsulation of the agglomerate.

Experimental ammonia-free phosphate-bonded investments using Mg(H2PO4)2.

PubMed

Zhang, Z; Tamaki, Y; Miyazaki, T

2001-12-01

In previous study, we found that Mg(H2PO4)2 instead of NH4H2PO4 was available as a binder material for phosphate-bonded investments and possibly could be used to develop the phosphate-bonded investment without ammonia gas release. The purpose of the present study was to develop the experimental ammonia-free phosphate-bonded investments by investigating suitable refractories. Mg(H2PO4)2.nH2O and MgO were prepared as a binder. Cristobalite and quartz were selected as refractories. The power ratio of MgO/Mg(H2PO4)2.nH2O was set constant at 1.2 according to our previous findings. Fundamental properties of dental investment such as strength, manipulation and expansion were evaluated. Using cristobalite as the refractory material, further investigations were performed. The refractory/binder ratio was definitely effective. The increase of this ratio led to low mold strength and large mold expansion. The present findings suggested that C5 was desirable for dental investment.

Characterization of origami shape memory metamaterials (SMMM) made of bio-polymer blends

NASA Astrophysics Data System (ADS)

Kshad, Mohamed Ali E.; Naguib, Hani E.

2016-04-01

Shape memory materials (SMMs) are materials that can return to their virgin state and release mechanically induced strains by external stimuli. Shape memory polymers (SMPs) are a class of SMMs that show a high shape recoverability and which have attractive potential for structural applications. In this paper, we experimentally study the shape memory effect of origami based metamaterials. The main focus is on the Muira origami metamaterials. The fabrication technique used to produce origami structure is direct molding where all the geometrical features are molded from thermally virgin polymers without post folding of flat sheets. The study shows experimental investigations of shape memory metamaterials (SMMMs) made of SMPs that can be used in different applications such as medicine, robotics, and lightweight structures. The origami structure made from SMP blends, activated with uniform heating. The effect of blend composition on the shape memory behavior was studied. Also the influence of the thermomechanical and the viscoelastic properties of origami unit cell on the activation process have been discussed, and stress relaxation and shape recovery were investigated. Activation process of the unit cell has been demonstrated.

Anticipating environmental and environmental-health implications of extreme storms: ARkStorm scenario

USGS Publications Warehouse

Plumlee, Geoffrey S.; Alpers, Charles N.; Morman, Suzette A.; San Juan, Carma A.

2016-01-01

The ARkStorm Scenario predicts that a prolonged winter storm event across California would cause extreme precipitation, flooding, winds, physical damages, and economic impacts. This study uses a literature review and geographic information system-based analysis of national and state databases to infer how and where ARkStorm could cause environmental damages, release contamination from diverse natural and anthropogenic sources, affect ecosystem and human health, and cause economic impacts from environmental-remediation, liability, and health-care costs. Examples of plausible ARkStorm environmental and health concerns include complex mixtures of contaminants such as petroleum, mercury, asbestos, persistent organic pollutants, molds, and pathogens; adverse physical and contamination impacts on riverine and coastal marine ecosystems; and increased incidences of mold-related health concerns, some vector-borne diseases, and valley fever. Coastal cities, the San Francisco Bay area, the Sacramento-San Joaquin River Delta, parts of the Central Valley, and some mountainous areas would likely be most affected. This type of screening analysis, coupled with follow-up local assessments, can help stakeholders in California and disaster-prone areas elsewhere better plan for, mitigate, and respond to future environmental disasters.

Environmental Sustainability and Mold Hygiene in Buildings

PubMed Central

Ng, Tsz Wai; Lai, Ka Man

2018-01-01

Environmental sustainability is one of the key issues in building management. In Hong Kong, one of the initiatives is to reduce the operation hours of air-conditioning in buildings to cut down energy consumption. In this study, we reported a mold contamination case in a newly refurbished laboratory, in which the air-conditioner was switched from 24- to 18-h mode after refurbishment. In order to prevent mold recurrence, the air-conditioner was switched back to 24-h mode in the laboratory. During the mold investigation, visible mold patches in the laboratory were searched and then cultured, counted and identified. Building and environmental conditions were recorded, and used to deduce different causes of mold contamination. Eight contaminated sites including a wall, a bench, some metal and plastic surfaces and seven types of molds including two Cladosporium spp., two Aspergillus spp., one Rhizopus sp., one Trichoderma sp., and one Tritirachium sp. were identified. Cladosporium spp. were the most abundant and frequently found molds in the laboratory. The contaminated areas could have one to five different species on them. Based on the mold and environmental conditions, several scenarios causing the mold contamination were deduced, and different mold control measures were discussed to compare them with the current solution of using 24-h air-conditioning to control mold growth. This study highlights the importance of mold hygiene in sustainable building management. PMID:29617339

Environmental Sustainability and Mold Hygiene in Buildings.

PubMed

Wu, Haoxiang; Ng, Tsz Wai; Wong, Jonathan Wc; Lai, Ka Man

2018-04-04

Environmental sustainability is one of the key issues in building management. In Hong Kong, one of the initiatives is to reduce the operation hours of air-conditioning in buildings to cut down energy consumption. In this study, we reported a mold contamination case in a newly refurbished laboratory, in which the air-conditioner was switched from 24- to 18-h mode after refurbishment. In order to prevent mold recurrence, the air-conditioner was switched back to 24-h mode in the laboratory. During the mold investigation, visible mold patches in the laboratory were searched and then cultured, counted and identified. Building and environmental conditions were recorded, and used to deduce different causes of mold contamination. Eight contaminated sites including a wall, a bench, some metal and plastic surfaces and seven types of molds including two Cladosporium spp., two Aspergillus spp., one Rhizopus sp., one Trichoderma sp., and one Tritirachium sp. were identified. Cladosporium spp. were the most abundant and frequently found molds in the laboratory. The contaminated areas could have one to five different species on them. Based on the mold and environmental conditions, several scenarios causing the mold contamination were deduced, and different mold control measures were discussed to compare them with the current solution of using 24-h air-conditioning to control mold growth. This study highlights the importance of mold hygiene in sustainable building management.

Human Abuse Potential of an Abuse-Deterrent (AD), Extended-Release (ER) Morphine Product Candidate (Morphine-ADER Injection-Molded Tablets) vs Extended-Release Morphine Administered Intranasally in Nondependent Recreational Opioid Users

PubMed Central

Webster, Lynn R.; Smith, Michael D.; Lawler, John; Lindhardt, Karsten; Dayno, Jeffrey M.

2017-01-01

Abstract Objective. To compare the relative human abuse potential after insufflation of manipulated morphine abuse-deterrent, extended-release injection-molded tablets (morphine-ADER-IMT) with that of marketed morphine ER tablets. Methods. A randomized, double-blind, double-dummy, active- and placebo-controlled five-way crossover study was performed with adult volunteers who were experienced, nondependent, recreational opioid users. After intranasal (IN) administration of manipulated high-volume (HV) morphine-ADER-IMT (60 mg), participants were randomized (1:1:1:1) to receive IN manipulated low-volume (LV) morphine ER (60 mg), IN manipulated LV morphine-ADER-IMT, intact oral morphine-ADER-IMT (60 mg), and placebo in crossover fashion. Pharmacodynamic and pharmacokinetic assessments included peak effect of drug liking (Emax; primary endpoint) using drug liking visual analog scale (VAS) score, Emax using overall drug liking, and take drug again (TDA) VASs scores, and mean abuse quotient (AQ), a pharmacokinetic parameter associated with drug liking. Results. Forty-six participants completed the study. After insufflation of HV morphine-ADER-IMT and LV morphine-ADER-IMT, drug liking Emax was significantly lower (P < 0.0001) compared with IN morphine ER. Overall drug liking and TDA Emax values were significantly lower (P < 0.0001) after insufflation of HV morphine-ADER-IMT and LV morphine-ADER-IMT compared with IN morphine ER. Mean AQ was lower after insufflation of HV (9.2) and LV (2.3) morphine-ADER-IMT or ingestion of oral morphine-ADER-IMT (5.5) compared with insufflation of LV morphine ER (37.2). Conclusions. All drug liking, take drug again, and abuse quotient endpoints support a significantly lower abuse potential with insufflation of manipulated morphine-ADER-IMT compared with manipulated and insufflated non-AD ER morphine. PMID:27651510

Biophysical characterization of hydrogel-core, lipid-shell nanoparticles (nanolipogels) for HIV chemoprophylaxis

NASA Astrophysics Data System (ADS)

Mahadevan, Reena

Nanoparticles are emerging as versatile vehicles for drug delivery, providing targeting, protection, and controlled-release capabilities to encapsulated cargo. Polymeric nanoparticles made from poly(lactide-co-glycolide) (PLGA) are biodegradable, exhibit tunable drug release, and have encapsulated a wide variety of biological agents. However, PLGA nanoparticles are relatively inefficient at encapsulating small-molecule hydrophilic drugs. Liposomes encapsulate greater amounts of hydrophilic agents and demonstrate good cellular affinity; however, they lack controlled-release functionality. Hydrogel-core lipid-shell nanoparticles, or nanolipogels, combine the controlled-release capability of polymeric nanocarriers with the hydrophilic and cellular affinity of liposomes into a single drug delivery vehicle. This study establishes a facile, reproducible synthetic protocol for nanolipogels and evaluates hydrogel swelling as a mechanism for release of the small hydrophilic antiretroviral azidothymidine from nanolipogels.

28 CFR 8.6 - Quick-release authority.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-release authority. Where the forfeiture proceedings are administrative, the Special Agent in Charge, prior to forfeiture, is authorized to release property seized for forfeiture. The property can be quick... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Quick-release authority. 8.6 Section 8.6...

Method for making an elastomeric member with end pieces

DOEpatents

Hoppie, Lyle O.; McNinch, Jr., Joseph H.; Nowell, Gregory C.

1984-01-01

A molding process for molding an elongated elastomeric member (60) with wire mesh sleeves (16) bonded to the ends (14). A molding preform (10) of elastomeric material is positioned within a seamless mold cylinder (26), and the open ends of the wire mesh sleeves (16) are mounted to end plug assemblies (30) slidably received into the mold cylinder (26) and positioned against the ends (14) of the preform (10). A specialized profile is formed into surfaces (44) of the respective end plug assemblies (30) and by heating of the mold (26), the ends (14) of the elastomeric preform (10) are molded to the profile, as well as bonded to the reinforcing wire mesh sleeves (16). Vacuum is applied to the interior of the mold to draw outgassing vapors through relief spaces therethrough. The completed elastomeric member (60) is removed from the mold cylinder (26) by stretching, the consequent reduction in diameter enabling ready separation from the mold cylinder (26) and removal thereof.

High resolution PFPE-based molding High resolution PFPE-based molding High resolution PFPE-based molding techniques for nanofabrication of high pattern density sub-20 nm features: A fundamental materials approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, Stuart S; Samulski, Edward; Lopez, Renee

2010-01-01

ABSTRACT. Described herein is the development and investigation of PFPE-based elastomers for high resolution replica molding applications. The modulus of the elastomeric materials was increased through synthetic and additive approaches while maintaining relatively low surface energies (<25 mN/m). Using practically relevant large area master templates, we show that the resolution of the molds is strongly dependant upon the elastomeric mold modulus. A composite mold approach was used to form flexible molds out of stiff, high modulus materials that allow for replication of sub-20 nm post structures. Sub-100 nm line grating master templates, formed using e-beam lithography, were used to determinemore » the experimental stability of the molding materials. It was observed that as the feature spacing decreased, high modulus composite molds were able to effectively replicate the nano-grating structures without cracking or tear-out defects that typically occur with high modulus elastomers.« less

Hydrogen silsesquioxane mold coatings for improved replication of nanopatterns by injection molding

NASA Astrophysics Data System (ADS)

Hobæk, Thor Christian; Matschuk, Maria; Kafka, Jan; Pranov, Henrik J.; Larsen, Niels B.

2015-03-01

We demonstrate the replication of nanosized pillars in polymer (cyclic olefin copolymer) by injection molding using nanostructured thermally cured hydrogen silsesquioxane (HSQ) ceramic coatings on stainless steel mold inserts with mold nanostructures produced by a simple embossing process. At isothermal mold conditions, the average pillar height increases by up to 100% and a more uniform height distribution is observed compared to a traditional metal mold insert. Thermal heat transfer simulations predict that the HSQ film retards the cooling of the polymer melt during the initial stages of replication, thus allowing more time to fill the nanoscale cavities compared to standard metal molds. A monolayer of a fluorinated silane (heptadecafluorotrichlorosilane) deposited on the mold surface reduces the mold/polymer interfacial energy to support demolding of the polymer replica. The mechanical stability of thermally cured HSQ makes it a promising material for nanopattern replication on an industrial scale without the need for slow and energy intensive variotherm processes.

Functional food red yeast rice (RYR) for metabolic syndrome amelioration: a review on pros and cons.

PubMed

Patel, Seema

2016-05-01

Red yeast rice (RYR), the fermentation product of mold Monascus purpureus has been an integral part of Oriental food and traditional Chinese medicine, long before the discovery of their medicinal roles. With the identification of bioactive components as polyketide pigments (statins), and unsaturated fatty acids, RYR has gained a nutraceutical status. Hypercholesterolemic effect of this fermented compound has been validated and monacolin K has been recognized as the pivotal component in cholesterol alleviation. Functional similarity with commercial drug lovastatin sans the side effects has catapulted its popularity in other parts of the world as well. Apart from the hypotensive role, ameliorative benefits of RYR as anti-inflammatory, antidiabetic, anticancer and osteogenic agent have emerged, fueling intense research on it. Mechanistic studies have revealed their interaction with functional agents like coenzyme Q10, astaxanthin, vitamin D, folic acid, policosanol, and berberine. On the other hand, concurrence of mycotoxin citrinin and variable content of statin has marred its integration in mainstream medication. In this disputable scenario, evaluation of the scopes and lacunae to overcome seems to contribute to an eminent area of healthcare. Red yeast rice (RYR), the rice-based fermentation product of mold Monascus purpureus is a functional food. Its bioactive component monacolin K acts like synthetic drug lovastatin, without the severe side effects of the latter. RYR has been validated to lower cholesterol, control high blood pressure; confer anti-flammation, hypoglycaemic, anticancer and osteogenic properties. However, dose inconsistency and co-occurrence of toxin citrinin hampers its dietary supplementation prospect. Further research might facilitate development of RYR as a nutraceutical.

The influence of polymeric excipients on the process of pharmaceutical availability of therapeutic agents from a model drug form. Part I. In formulations with controlled disintegration and release time.

PubMed

Nachajski, Michal Jakub; Zgoda, Marian Mikołaj

2010-01-01

Pre-formulation research was conducted on the application of Ex. Echinaceae aq. siccum in the production of a quickly disintegrating suspension tablet, a lozenge with kariostatic sugar alcohols (mannitol, sorbitol), and, above all, a solid drug form with controlled release of therapeutic agents included in the extract. Morphological parameters of tablets obtained in the course of experiment were estimated and the profiles of the release (diffusion) ofhydrophilic therapeutic agents into model receptor fluids with varying values of osmolarity (0.1 mol HCl approximately 200 mOsm/l, hypotonic hydrating fluid approximately 143 mOsm/l, and compensatory paediatric fluid approximately 272 mOsm/l) were examined. The study focused on the technological problem of determining the effect of hydrogel Carbopol structure on the ordering of diffusion ofhydrophilic therapeutic agents from a model drug form (a tablet) into model fluids with variable osmolarity.

Evaluation of yeasts obtained from Antarctic soil samples as biocontrol agents for the management of postharvest diseases of apple (Malus × domestica).

PubMed

Vero, Silvana; Garmendia, Gabriela; González, M Belén; Bentancur, Oscar; Wisniewski, Michael

2013-03-01

Psychrotrophic yeasts were isolated from Antarctic soils, selected based on their ability to grow in apple juice at low temperatures, and were evaluated as potential biocontrol agents for the management of postharvest diseases of apple during cold storage. Among the species recovered, an isolate of Leucosporidium scottii, designated At17, was identified as a good biocontrol agent for blue and gray mold of two apple cultivars. The selected isolate produced soluble and volatile antifungal substances that were inhibitory to apple pathogens. Siderophore production was also demonstrated, but it did not appear to play a role in pathogen inhibition. The selected yeast had the capacity to form a biofilm when grown in apple juice, which is considered an important attribute of postharvest antagonists to successfully colonize wounds and intact fruit surfaces. At17 was resistant to commonly used postharvest fungicides, so application of a combination of low-dose fungicide along with the biocontrol agent could be used as an integrated management practice. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Effect of Cross Sectional Geometry on PDMS Micro Peristaltic Pump Performance: Comparison of SU-8 Replica Molding vs. Micro Injection Molding

PubMed Central

Graf, Neil J.

2013-01-01

Two different fabrication methods were employed to fabricate micropumps with different cross-sectional channel geometries. The first was to fabricate rectangular cross-sectional microchannel geometries using the well known fabrication method of replica molding (REM).1 The second, and far less utilized fabrication technique, was to create microchannel molds using an in-house fabricated handheld micro injection molding apparatus. The injection mold apparatus was designed for use with elastomeric room temperature vulcanization (RTV) polymers, as opposed to most other injection molding machines, which are designed for use with thermoplastic polymers. The injection mold’s bottom plate was used as a microchannel molding template. The molding template was created by threading a small-diameter wire (150 μm or less) through the injection mold’s bottom plate, with subsequent adhesion and smoothing of a thin piece of aluminum foil over the wire-raised injection mold template. When molded against, the template produced a rounded/Gaussian-shaped PDMS microchannel. The design of the injection mold will be presented, along with a direct comparison for micropump performance metrics such as flow rate, valving characteristics, and maximum backpressures attainable for each of the respective micropump channel geometries. PMID:23917263

Challenges in mold manufacturing for high precision molded diffractive optical elements

NASA Astrophysics Data System (ADS)

Pongs, Guido; Bresseler, Bernd; Schweizer, Klaus; Bergs, Thomas

2016-09-01

Isothermal precision glass molding of imaging optics is the key technology for mass production of precise optical elements. Especially for numerous consumer applications (e.g. digital cameras, smart phones, …), high precision glass molding is applied for the manufacturing of aspherical lenses. The usage of diffractive optical elements (DOEs) can help to further reduce the number of lenses in the optical systems which will lead to a reduced weight of hand-held optical devices. But today the application of molded glass DOEs is limited due to the technological challenges in structuring the mold surfaces. Depending on the application submicrometer structures are required on the mold surface. Furthermore these structures have to be replicated very precisely to the glass lens surface. Especially the micro structuring of hard and brittle mold materials such as Tungsten Carbide is very difficult and not established. Thus a multitude of innovative approaches using diffractive optical elements cannot be realized. Aixtooling has investigated in different mold materials and different suitable machining technologies for the micro- and sub-micrometer structuring of mold surfaces. The focus of the work lays on ultra-precision grinding to generate the diffractive pattern on the mold surfaces. This paper presents the latest achievements in diffractive structuring of Tungsten Carbide mold surfaces by ultra-precision grinding.

Kinetics and Mechanisms of Chemical and Biological Agents Release from Biopolymeric Microcapsules.

PubMed

Vinceković, Marko; Jurić, Slaven; Đermić, Edyta; Topolovec-Pintarić, Snježana

2017-11-08

Kinetics and mechanisms of copper cations and Trichoderma viride spores release from uncoated and chitosan coated alginate microcapsules were investigated. The gelation of a fixed amount of sodium alginate at different concentrations of copper ion solutions resulted in distinct kinetics and release mechanisms. The increase in copper cation concentration promoted, but the presence of the chitosan layer on the microcapsule surface and the increase in microcapsule size reduced the rate of active agent release. Fitting to simple Korsmeyer-Peppas empirical model revealed that the underlying release mechanism (Fickian diffusion or a combination of the diffusion and erosion mechanisms) depends on the copper cation concentration and presence of T. viride spores. The investigation pointed out that the proper selection of formulation variables helps in designing microcapsules with the desirable release of copper ions and T. viride for plant protection and nutrition.

Chemical release from single-PMMA microparticles monitored by CARS microscopy

NASA Astrophysics Data System (ADS)

Enejder, Annika; Svedberg, Fredrik; Nordstierna, Lars; Nydén, Magnus

2011-03-01

Microparticles loaded with antigens, proteins, DNA, fungicides, and other functional agents emerge as ideal vehicles for vaccine, drug delivery, genetic therapy, surface- and crop protection. The microscopic size of the particles and their collective large specific surface area enables highly active and localized release of the functional substance. In order to develop designs with release profiles optimized for the specific application, it is desirable to map the distribution of the active substance within the particle and how parameters such as size, material and morphology affect release rates at single particle level. Current imaging techniques are limited in resolution, sensitivity, image acquisition time, or sample treatment, excluding dynamic studies of active agents in microparticles. Here, we demonstrate that the combination of CARS and THG microscopy can successfully be used, by mapping the spatial distribution and release rates of the fungicide and food preservative IPBC from different designs of PMMA microparticles at single-particle level. By fitting a radial diffusion model to the experimental data, single particle diffusion coefficients can be determined. We show that release rates are highly dependent on the size and morphology of the particles. Hence, CARS and THG microscopy provides adequate sensitivity and spatial resolution for quantitative studies on how singleparticle properties affect the diffusion of active agents at microscopic level. This will aid the design of innovative microencapsulating systems for controlled release.

Onto-Agents-Enabling Intelligent Agents on the Web

DTIC Science & Technology

2005-05-01

AIR FORCE RESEARCH LABORATORY INFORMATION DIRECTORATE ROME RESEARCH SITE ROME, NEW YORK STINFO FINAL REPORT This report has been reviewed...by the Air Force Research Laboratory, Information Directorate, Public Affairs Office (IFOIPA) and is releasable to the National Technical... Information Service (NTIS). At NTIS it will be releasable to the general public, including foreign nations. AFRL-IF-RS-TR-2005-178 has been reviewed

A Systems Approach to Depaint Chemistry

DTIC Science & Technology

2009-02-01

continuous colored film by curing through solvent evaporation, oxidation, catylization or other means. – Vehicle: Film former, binder, resin or polymer...impart large changes in properties. – Suspending agents – Driers – Anti-Skinning Agents – Wetting Agents – Anti- Foaming Agents – Coalescing Agents ...volatile stripper inside the coating. Paint Release Agent Coating Removal Mechanism Zone1: PRA Layer Zone2: PRA Initial Permeation into coating system Epoxy

Fabrication of robust tooling for mass production of polymeric microfluidic devices

NASA Astrophysics Data System (ADS)

Fu, G.; Tor, S. B.; Loh, N. H.; Hardt, D. E.

2010-08-01

Polymer microfluidic devices are gaining popularity for bio-applications. In both commonly used methods for the fabrication of polymer microfluidic devices, i.e. injection molding and hot-embossing, the quality of a mold insert is of high importance. Micro powder injection molding (μPIM) provides a suitable option for metal mold insert fabrication. In this paper, two mold inserts with micro-features of different patterns and sizes were produced using 316L stainless steel powder and an in-house binder system. The mold inserts were successfully used to produce cyclic olefin copolymer (COC, trade name TOPAS) micromixer plates with micro-channels of widths 100 µm and 50 µm. Compared with CNC-machined hot work steel mold inserts, the quality of the micro-channels is better as far as geometrical quality and dimensional tolerance are concerned. However, surface finish and flatness of the μPIM mold inserts are inferior to those of CNC-machined mold inserts.

Localized mold heating with the aid of selective induction for injection molding of high aspect ratio micro-features

NASA Astrophysics Data System (ADS)

Park, Keun; Lee, Sang-Ik

2010-03-01

High-frequency induction is an efficient, non-contact means of heating the surface of an injection mold through electromagnetic induction. Because the procedure allows for the rapid heating and cooling of mold surfaces, it has been recently applied to the injection molding of thin-walled parts or micro/nano-structures. The present study proposes a localized heating method involving the selective use of mold materials to enhance the heating efficiency of high-frequency induction heating. For localized induction heating, a composite injection mold of ferromagnetic material and paramagnetic material is used. The feasibility of the proposed heating method is investigated through numerical analyses in terms of its heating efficiency for localized mold surfaces and in terms of the structural safety of the composite mold. The moldability of high aspect ratio micro-features is then experimentally compared under a variety of induction heating conditions.

Evaluation of the microstructure, secondary dendrite arm spacing, and mechanical properties of Al-Si alloy castings made in sand and Fe-Cr slag molds

NASA Astrophysics Data System (ADS)

Narasimha Murthy, I.; Babu Rao, J.

2017-07-01

The microstructure and mechanical properties of as-cast A356 (Al-Si) alloy castings were investigated. A356 alloy was cast into three different molds composed of sand, ferrochrome (Fe-Cr) slag, and a mixture of sand and Fe-Cr. A sodium silicate-CO2 process was used to make the necessary molds. Cylindrical-shaped castings were prepared. Cast products with no porosity and a good surface finish were achieved in all of the molds. These castings were evaluated for their metallography, secondary dendrite arm spacing (SDAS), and mechanical properties, including hardness, compression, tensile, and impact properties. Furthermore, the tensile and impact samples were analyzed by fractography. The results show that faster heat transfer in the Fe-Cr slag molds than in either the silica sand or mixed molds led to lower SDAS values with a refined microstructure in the products cast in Fe-Cr slag molds. Consistent and enhanced mechanical properties were observed in the slag mold products than in the castings obtained from either sand or mixed molds. The fracture surface of the slag mold castings shows a dimple fracture morphology with a transgranular fracture nature. However, the fracture surfaces of the sand mold castings display brittle fracture. In conclusion, products cast in Fe-Cr slag molds exhibit an improved surface finish and enhanced mechanical properties compared to those of products cast in sand and mixed molds.

Controlled Release of Multiple Therapeutics from Silicone Hydrogel Contact Lenses.

PubMed

White, Charles James; DiPasquale, Stephen Anthony; Byrne, Mark Edward

2016-04-01

The majority of contact lens wearers experience a significant level of ocular discomfort associated with lens wear, often within hours of wear, related to dry lenses, inflammation, protein adhesion to the lens surface, etc. Application of controlled drug release techniques has focused on the incorporation and/or release of a single comfort molecule from a lens including high molecular weight comfort agents or pharmaceutical agents. Previous studies have sought to mitigate the occurrence of only single propagators of discomfort. Clinical studies with eye drop solutions have shown that a mixture of diverse comfort agents selected to address multiple propagators of discomfort provide the greatest and longest lasting sensations of comfort for the patient. In this paper, multiple propagators of discomfort are addressed through the simultaneous release of four molecules from a novel contact lens to ensure high level of lens wear comfort. Silicone hydrogel contact lenses were engineered via molecular imprinting strategies to simultaneously release up to four template molecules including hydropropyl methylcellulose (HPMC), trehalose, ibuprofen, and prednisolone. By adjusting the ratio of functional monomer to comfort molecule, a high level of control was demonstrated over the release rate. HPMC, trehalose, ibuprofen, and prednisolone were released at therapeutically relevant concentrations with varying rates from a single lens. The results indicate use as daily disposable lenses for single day release or extended-wear lenses with multiple day release. Imprinted lenses are expected to lead to higher efficacy for patients compared to topical eye drops by improving compliance and mitigating concentration peaks and valleys associated with multiple drops.

Controlled Release of Multiple Therapeutics from Silicone Hydrogel Contact Lenses

PubMed Central

White, Charles J.; DiPasquale, Stephen A.; Byrne, Mark E.

2016-01-01

Purpose The majority of contact lens wearers experience a significant level of ocular discomfort associated with lens wear, often within hours of wear, related to dry lenses, inflammation, protein adhesion to the lens surface, etc. Application of controlled drug release techniques has focused on the incorporation and/or release of a single comfort molecule from a lens including high molecular weight comfort agents or pharmaceutical agents. Previous studies have sought to mitigate the occurrence of only single propagators of discomfort. Clinical studies with eye drop solutions have shown that a mixture of diverse comfort agents selected to address multiple propagators of discomfort provide the greatest and longest lasting sensations of comfort for the patient. In this paper, multiple propagators of discomfort are addressed through the simultaneous release of four molecules from a novel contact lens to ensure high level of lens wear comfort. Methods Silicone hydrogel contact lenses were engineered via molecular imprinting strategies to simultaneously release up to four template molecules including hydropropyl methylcellulose (HPMC), trehalose, ibuprofen, and prednisolone. Results By adjusting the ratio of functional monomer to comfort molecule, a high level of control was demonstrated over the release rate. HPMC, trehalose, ibuprofen, and prednisolone were released at therapeutically relevant concentrations with varying rates from a single lens. Conclusions The results indicate use as daily disposable lenses for single day release or extended-wear lenses with multiple day release. Imprinted lenses are expected to lead to higher efficacy for patients compared to topical eye drops by improving compliance and mitigating concentration peaks and valleys associated with multiple drops. PMID:26945177

21 CFR 184.1978 - Carnauba wax.

Code of Federal Regulations, 2010 CFR

2010-04-01

... lubricant and release agent as defined in § 170.3(o)(18) of this chapter; and as a surface-finishing agent... manufacturing practice conditions of use: (1) The ingredient is used as an anticaking agent as defined § 170.3(o...

Self-Replenishing Vascularized Fouling-Release Surfaces

DOE PAGES

Howell, Caitlin; Vu, Thy L.; Lin, Jennifer J.; ...

2014-08-13

Inspired by the long-term effectiveness of living antifouling materials, we have developed a method for the selfreplenishment of synthetic biofouling-release surfaces. These surfaces are created by either molding or directly embedding 3D vascular systems into polydimethylsiloxane (PDMS) and filling them with a silicone oil to generate a nontoxic oil-infused material. When replenished with silicone oil from an outside source, these materials are capable of self-lubrication and continuous renewal of the interfacial fouling-release layer. Under accelerated lubricant loss conditions, fully infused vascularized samples retained significantly more lubricant than equivalent nonvascularized controls. Tests of lubricant-infused PDMS in static cultures of the infectiousmore » bacteria Staphylococcus aureus and Escherichia coli as well as the green microalgae Botryococcus braunii, Chlamydomonas reinhardtii, Dunaliella salina, and Nannochloropsis oculata showed a significant reduction in biofilm adhesion compared to PDMS and glass controls containing no lubricant. Further experiments on vascularized versus nonvascularized samples that had been subjected to accelerated lubricant evaporation conditions for up to 48 h showed significantly less biofilm adherence on the vascularized surfaces. These results demonstrate the ability of an embedded lubricant-filled vascular network to improve the longevity of fouling-release surfaces.« less

Clinical and cost effectiveness of eight disinfection methods for terminal disinfection of hospital isolation rooms contaminated with Clostridium difficile 027.

PubMed

Doan, L; Forrest, H; Fakis, A; Craig, J; Claxton, L; Khare, M

2012-10-01

Clostridium difficile spores can survive in the environment for months or years, and contaminated environmental surfaces are important sources of nosocomial C. difficile transmission. To compare the clinical and cost effectiveness of eight C. difficile environmental disinfection methods for the terminal cleaning of hospital rooms contaminated with C. difficile spores. This was a novel randomized prospective study undertaken in three phases. Each empty hospital room was disinfected, then contaminated with C. difficile spores and disinfected with one of eight disinfection products: hydrogen peroxide vapour (HPV; Bioquell Q10) 350-700 parts per million (ppm); dry ozone at 25 ppm (Meditrox); 1000 ppm chlorine-releasing agent (Actichlor Plus); microfibre cloths (Vermop) used in combination with and without a chlorine-releasing agent; high temperature over heated dry atomized steam cleaning (Polti steam) in combination with a sanitizing solution (HPMed); steam cleaning (Osprey steam); and peracetic acid wipes (Clinell). Swabs were inoculated on to C. difficile-selective agar and colony counts were performed pre and post disinfection for each method. A cost-effectiveness analysis was also undertaken comparing all methods to the current method of 1000 ppm chlorine-releasing agent (Actichlor Plus). Products were ranked according to the log(10) reduction in colony count from contamination phase to disinfection. The three statistically significant most effective products were hydrogen peroxide (2.303); 1000 ppm chlorine-releasing agent (2.223) and peracetic acid wipes (2.134). The cheaper traditional method of using a chlorine-releasing agent for disinfection was as effective as modern methods. Copyright © 2012 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Effects of membrane composition on release of model hydrophilic compound from osmotic delivery systems.

PubMed

Ozdemir, N; Ozalp, Y; Ozkan, Y

2000-01-01

In this study, the effects of surface-active agents in different types and concentrations, added into the coating solution, on release of model hydrophilic compound have been examined. For this purpose, the tablets, prepared with the use of methylene blue as a model substance, were coated by spray coating technique with cellulose acetate solution containing polyethylene glycol 400 as a plasticizer. In addition, cetylpyridinium chloride as cationic surface-active agent and sodium lauryl sulphate as anionic surface-active agent were added into coating solution in different concentrations. After creating a delivery orifice by a microdrill on the tablets, release of model hydrophilic compound was tested by the USP paddle method. The data obtained were evaluated according to the different kinetics and the mechanism of release from the preparations was examined. The surface properties of the coating material were investigated by scanning electron microscope taken before and after the contact with medium fluid, as well as the mechanical properties by tensile tests. In conclusion, it has been found that the cationic surface active agent, cetylpyridinium chloride reduced the lag time, observed during the release of model hydrophilic compound, as a result of its enhancing effect on wettability of tablets by reducing the contact angle between the medium fluid and the coating material. On the other hand, the anionic surface active agent, sodium lauryl sulphate has been inactivated possibly due to the interaction with model hydrophilic compound that has cationic properties and/or substances contained in membrane composition; thus, the lag time has not decreased and furthermore, a significant decrease in the delivery rate of model hydrophilic compound has been observed.

Development of In-Mold Assembly Methods for Producing Mesoscale Revolute Joints

DTIC Science & Technology

2009-01-01

tolerances available for manufacturing the molds are relatively low. Any inaccuracy in mold First stage part (ABS) Second stage part ( LDPE ) Pins...case, the viscosity of LDPE is also a function of temperature. For each of these cases, they have considered the filling of a thin mold cavity. From...predicting the weld-line strengths of crystalline polymers such as LDPE . 63 3 Issues in In-Mold Assembly at the Mesoscale 3.1 Motivation In-mold

Fabrication of metallic microstructures by micromolding nanoparticles

DOEpatents

Morales, Alfredo M.; Winter, Michael R.; Domeier, Linda A.; Allan, Shawn M.; Skala, Dawn M.

2002-01-01

A method is provided for fabricating metallic microstructures, i.e., microcomponents of micron or submicron dimensions. A molding composition is prepared containing an optional binder and nanometer size (1 to 1000 nm in diameter) metallic particles. A mold, such as a lithographically patterned mold, preferably a LIGA or a negative photoresist mold, is filled with the molding composition and compressed. The resulting microstructures are then removed from the mold and the resulting metallic microstructures so provided are then sintered.

Design and Fabrication of FRP Truck Trailer Side Racks.

DTIC Science & Technology

1983-08-01

0.100 in. All contact surfaces in the mold were sealed with white shellac and finished with five coats of carnauba wax . The completed mold is shown in...Figure 10. 15 II Figure 10. FRP prototype mold. FRP molding procedures were duplicated for each part produced. In general, the waxed mold was coated

ILLUSTRATED HANDBOOK OF SOME COMMON MOLDS.

ERIC Educational Resources Information Center

CHANDLER, MARION N.

THIS DOCUMENT IS A PICTURE GUIDE FOR THE IDENTIFICATION OF TEN COMMON MOLDS. IT IS DESIGNED FOR USE WITH THE ELEMENTARY SCIENCE STUDY UNIT "MICROGARDENING" AND IS SUGGESTED FOR UPPER ELEMENTARY GRADES. INCLUDED FOR EACH MOLD ARE COLOR PHOTOGRAPHS AND PHOTOMICROGRAPHS OF THE INTACT MOLD MASS AND OF THE MOLD'S SPORE PRODUCING STRUCTURES.…

40 CFR Table 9 to Subpart Wwww of... - Initial Compliance With Work Practice Standards

Code of Federal Regulations, 2014 CFR

2014-07-01

... compression/injection molding uncover, unwrap or expose only one charge per mold cycle per compression/injection molding machine. For machines with multiple molds, one charge means sufficient material to fill... cycle per compression/injection molding machine, or prior to the loader, hoppers are closed except when...

Micro-optical fabrication by ultraprecision diamond machining and precision molding

NASA Astrophysics Data System (ADS)

Li, Hui; Li, Likai; Naples, Neil J.; Roblee, Jeffrey W.; Yi, Allen Y.

2017-06-01

Ultraprecision diamond machining and high volume molding for affordable high precision high performance optical elements are becoming a viable process in optical industry for low cost high quality microoptical component manufacturing. In this process, first high precision microoptical molds are fabricated using ultraprecision single point diamond machining followed by high volume production methods such as compression or injection molding. In the last two decades, there have been steady improvements in ultraprecision machine design and performance, particularly with the introduction of both slow tool and fast tool servo. Today optical molds, including freeform surfaces and microlens arrays, are routinely diamond machined to final finish without post machining polishing. For consumers, compression molding or injection molding provide efficient and high quality optics at extremely low cost. In this paper, first ultraprecision machine design and machining processes such as slow tool and fast too servo are described then both compression molding and injection molding of polymer optics are discussed. To implement precision optical manufacturing by molding, numerical modeling can be included in the future as a critical part of the manufacturing process to ensure high product quality.

Enhancing the efficacy of cytotoxic agents for cancer therapy using photochemical internalisation

PubMed Central

Moore, Caroline M.; Loizidou, Marilena; MacRobert, Alexander J.; Woodhams, Josephine H.

2016-01-01

Photochemical internalisation (PCI) is a technique for improving cellular delivery of certain bioactive agents which are prone to sequestration within endolysosomes. There is a wide range of agents suitable for PCI‐based delivery including toxins, oligonucleotides, genes and immunoconjugates which demonstrates the versatility of this technique. The basic mechanism of PCI involves triggering release of the agent from endolysosomes within the target cells using a photosensitiser which is selectively retained with the endolysosomal membranes. Excitation of the photosensitiser by visible light leads to disruption of the membranes via photooxidative damage thereby releasing the agent into the cytosol. This treatment enables the drugs to reach their intended subcellular target more efficiently and improves their efficacy. In this review we summarise the applications of this technique with the main emphasis placed on cancer chemotherapy. PMID:25758607

Size-Tunable and Functional Core-Shell Structured Silica Nanoparticles for Drug Release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi, Fangli; Guo, Ya Nan; Liu, Jun

2010-02-18

Size-tunable silica cross-linked micellar core-shell nanoparticles (SCMCSNs) were successfully synthesized from a Pluronic nonionic surfactant (F127) template system with organic swelling agents such as 1,3,5-trimethylbenzene (TMB) and octanoic acid at room temperature. The size and morphology of SCMCSNs were directly evidenced by TEM imaging and DLS measurements (up to ~90 nm). Pyrene and coumarin 153 (C153) were used as fluorescent probe molecules to investigate the effect and location of swelling agent molecules. Papaverine as a model drug was used to measure the loading capacity and release property of nanoparticles. The swelling agents can enlarge the nanoparticle size and improve themore » drug loading capacity of nanoparticles. Moreover, the carboxylic acid group of fatty acid can adjust the release behavior of the nanoparticles.« less

Mold exposure and health effects following hurricanes Katrina and Rita.

PubMed

Barbeau, Deborah N; Grimsley, L Faye; White, LuAnn E; El-Dahr, Jane M; Lichtveld, Maureen

2010-01-01

The extensive flooding in the aftermath of Hurricanes Katrina and Rita created conditions ideal for indoor mold growth, raising concerns about the possible adverse health effects associated with indoor mold exposure. Studies evaluating the levels of indoor and outdoor molds in the months following the hurricanes found high levels of mold growth. Homes with greater flood damage, especially those with >3 feet of indoor flooding, demonstrated higher levels of mold growth compared with homes with little or no flooding. Water intrusion due to roof damage was also associated with mold growth. However, no increase in the occurrence of adverse health outcomes has been observed in published reports to date. This article considers reasons why studies of mold exposure after the hurricane do not show a greater health impact.

Mold prevention strategies and possible health effects in the aftermath of hurricanes and major floods.

PubMed

Brandt, Mary; Brown, Clive; Burkhart, Joe; Burton, Nancy; Cox-Ganser, Jean; Damon, Scott; Falk, Henry; Fridkin, Scott; Garbe, Paul; McGeehin, Mike; Morgan, Juliette; Page, Elena; Rao, Carol; Redd, Stephen; Sinks, Tom; Trout, Douglas; Wallingford, Kenneth; Warnock, David; Weissman, David

2006-06-09

Extensive water damage after major hurricanes and floods increases the likelihood of mold contamination in buildings. This report provides information on how to limit exposure to mold and how to identify and prevent mold-related health effects. Where uncertainties in scientific knowledge exist, practical applications designed to be protective of a person's health are presented. Evidence is included about assessing exposure, clean-up and prevention, personal protective equipment, health effects, and public health strategies and recommendations. The recommendations assume that, in the aftermath of major hurricanes or floods, buildings wet for <48 hours will generally support visible and extensive mold growth and should be remediated, and excessive exposure to mold-contaminated materials can cause adverse health effects in susceptible persons regardless of the type of mold or the extent of contamination. For the majority of persons, undisturbed mold is not a substantial health hazard. Mold is a greater hazard for persons with conditions such as impaired host defenses or mold allergies. To prevent exposure that could result in adverse health effects from disturbed mold, persons should 1) avoid areas where mold contamination is obvious; 2) use environmental controls; 3) use personal protective equipment; and 4) keep hands, skin, and clothing clean and free from mold-contaminated dust. Clinical evaluation of suspected mold-related illness should follow conventional clinical guidelines. In addition, in the aftermath of extensive flooding, health-care providers should be watchful for unusual mold-related diseases. The development of a public health surveillance strategy among persons repopulating areas after extensive flooding is recommended to assess potential health effects and the effectiveness of prevention efforts. Such a surveillance program will help CDC and state and local public health officials refine the guidelines for exposure avoidance, personal protection, and clean-up and assist health departments to identify unrecognized hazards.

Interim Report on Mixing During the Casting of LEU-10Mo Plates in the Triple Plate Molds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aikin, Jr., Robert M.

LEU-10%Mo castings are commonly produced by down blending unalloyed HEU with a DU-12.7%Mo master-alloy. This work uses process modeling to provide insight into the mixing of the unalloyed uranium and U-Mo master alloy during melting and mold filling of a triple plate casting. Two different sets of situations are considered: (1) mixing during mold filling from a compositionally stratified crucible and (2) convective mixing of a compositionally stratified crucible during mold heating. The mold filling simulations are performed on the original Y-12 triple plate mold and the horizontal triple plate mold.

Development of processes and techniques for molding thermally stable, fire-retardant, low-smoke-emitting polymeric materials

NASA Technical Reports Server (NTRS)

Silverman, B.

1979-01-01

All available newly developed nonmetallic thermally stable polymers were examined for the development of processes and techniques by compression molding, injection molding, or thermoforming cabin interior parts. Efforts were directed toward developing molding techniques of new polymers to economically produce usable nonmetallic molded parts. Data on the flame resistant characteristics of the materials were generated from pilot plant batches. Preliminary information on the molding characteristics of the various thermoplastic materials was obtained by producing actual parts.

HIGH TEMPERATURE REFRACTORY COATING FOR GRAPHITE MOLDS

DOEpatents

Stoddard, S.D.

1958-10-21

An improved foundry mold coating for use with graphite molds used in the casting of uranium is presented. The refractory mold coating serves to keep the molten uranium from contact with graphite of the mold and thus prevents carbon pickup by the molten metal. The refractory coating is made by dry mixing certain specific amounts of aluminum oxide, bentonite, Tennessee ball clay, and a soluble silicate salt. Water is then added to the mixture and the suspension thus formed is applied by spraying onto the mold.

76 FR 29754 - Proposed Data Collections Submitted for Public Comment and Recommendations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-23

... Agent or Toxin, (3) Report of Theft, Loss, or Release of Select Agent and Toxin, (4) Report of..., Use, and Transfer of Select Agents and Toxins (OMB Control No. 0920-0576)--Revision--Office of Public Health Preparedness and Response (OPHPR), Division of Select Agents and Toxins, Centers for Disease...

75 FR 76460 - Lymphohematopoietic Cancers Induced by Chemicals and Other Agents: Overview and Implications for...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-08

... emphasis on leukemia and leukemia-inducing agents. In addition, the document also focuses on how mechanistic information on human leukemia-inducing agents can inform risk assessment. EPA is releasing this... primary emphasis on leukemia and leukemia-inducing agents. II. How to Submit Technical Comments to the...

Behavior of sulfur mustard in sand, concrete, and asphalt matrices: Evaporation, degradation, and decontamination.

PubMed

Jung, Hyunsook; Choi, Seungki

2017-10-15

The evaporation, degradation, and decontamination of sulfur mustard on environmental matrices including sand, concrete, and asphalt are described. A specially designed wind tunnel and thermal desorber in combination with gas chromatograph (GC) produced profiles of vapor concentration obtained from samples of the chemical agent deposited as a drop on the surfaces of the matrices. The matrices were exposed to the chemical agent at room temperature, and the degradation reactions were monitored and characterized. A vapor emission test was also performed after a decontamination process. The results showed that on sand, the drop of agent spread laterally while evaporating. On concrete, the drop of the agent was absorbed immediately into the matrix while spreading and evaporating. However, the asphalt surface conserved the agent and slowly released parts of the agent over an extended period of time. The degradation reactions of the agent followed pseudo first order behavior on the matrices. Trace amounts of the residual agent present at the surface were also released as vapor after decontamination, posing a threat to the exposed individual and environment.

Release of Self-Healing Agents in a Material: What Happens Next?

PubMed

Lee, Min Wook; Yoon, Sam S; Yarin, Alexander L

2017-05-24

A microfluidic chip-like setup consisting of a vascular system of microchannels alternatingly filled with either a resin monomer or a curing agent is used to study the intrinsic physical healing mechanism in self-healing materials. It is observed that, as a prenotched crack propagates across the chip, the resin and curing agent are released from the damaged channels. Subsequently, both the resin and the curing agent wet the surrounding polydimethylsiloxane (PDMS) matrix and spread over the crack banks until the two blobs come in contact, mix, and polymerize through an organometallic cross-linking reaction. Moreover, the polymerized domains form a system of pillars, which span the crack banks on the opposite side. This "stitching" phenomenon prevents further propagation of the crack.

Heparin-based hydrogels with tunable sulfation & degradation for anti-inflammatory small molecule delivery.

PubMed

Peng, Yifeng; Tellier, Liane E; Temenoff, Johnna S

2016-08-16

Sustained release of anti-inflammatory agents remains challenging for small molecule drugs due to their low molecular weight and hydrophobicity. Therefore, the goal of this study was to control the release of a small molecule anti-inflammatory agent, crystal violet (CV), from hydrogels fabricated with heparin, a highly sulfated glycosaminoglycan capable of binding positively-charged molecules such as CV. In this system, both electrostatic interactions between heparin and CV and hydrogel degradation were tuned simultaneously by varying the level of heparin sulfation and varying the amount of dithiothreitol within hydrogels, respectively. It was found that heparin sulfation significantly affected CV release, whereby more sulfated heparin hydrogels (Hep and Hep(-N)) released CV with near zero-order release kinetics (R-squared values between 0.96-0.99). Furthermore, CV was released more quickly from fast-degrading hydrogels than slow-degrading hydrogels, providing a method to tune total CV release between 5-15 days while maintaining linear release kinetics. In particular, N-desulfated heparin hydrogels exhibited efficient CV loading (∼90% of originally included CV), near zero-order CV release kinetics, and maintenance of CV bioactivity after release, making this hydrogel formulation a promising CV delivery vehicle for a wide range of inflammatory diseases.

Optimization of Adhesive Pastes for Dental Caries Prevention.

PubMed

Sodata, Patteera; Juntavee, Apa; Juntavee, Niwut; Peerapattana, Jomjai

2017-11-01

Dental caries prevention products available on the market contain only remineralizing agents or antibacterial agents. This study aimed to develop adhesive pastes containing calcium phosphate and α-mangostin for dental caries prevention using the optimization technique. Calcium phosphate was used as a remineralizing agent, and extracted α-mangostin was used as an antibacterial agent. The effect of the independent variables, which were fumed silica, Eudragit ® EPO, polyethylene glycol, and ethyl alcohol, on the responses was investigated. The drying time, erosion rate, calcium release rate, and α-mangostin release rate were established as the measured responses. An equation and a model of the relationship were constructed. An optimal formulation was obtained, and its effect on dental caries prevention was investigated using the pH-cycling model. The quadratic equation revealed that the drying time, calcium release rate, and α-mangostin release rate tended to decrease when increasing the fumed silica and decreasing other factors. The erosion rate tended to increase when decreasing Eudragit ® EPO and increasing other factors. The observed responses of the optimal adhesive pastes were not significantly different from the predicted responses. This result demonstrated that optimization is an efficient technique in the formulation development of the adhesive pastes. In addition, the optimal adhesive pastes could enhance acid resistance activity to the tooth enamel.

Indoor Molds and Respiratory Hypersensitivity: A Comparison of Selected Molds and House Dust Mite Induced Responses in a Mouse Model

EPA Science Inventory

Introduction/Study Goal Molds are ubiquitous in the environment and exposures to molds contribute to various human diseases including allergic lung diseases. The Institute of Medicine reports and WHO gUidelines concluded that the role of molds in asthma induction is not clear bu...

Curable liquid hydrocarbon prepolymers containing hydroxyl groups and process for producing same

NASA Technical Reports Server (NTRS)

Rhein, R. A.; Ingham, J. D. (Inventor)

1978-01-01

Production of hydroxyl containing curable liquid hydrocarbon prepolymers by ozonizing a high molecular weight saturated hydrocarbon polymer such as polyisobutylene or ethylene propylene rubber is discussed. The ozonized material is reduced using reducing agents, preferably diisobutyl aluminum hydride, to form the hydroxyl containing liquid prepolymers having a substantially lower molecular weight than the parent polymer. The resulting curable liquid hydroxyl containing prepolymers can be poured into a mold and readily cured, with reactants such as toluene diisocyanate, to produce highly stable elastomers having a variety of uses such as binders for solid propellants.

7 CFR 356.5 - Bonded release.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., in place of any property specified in § 356.1 and release the property to the owner or agent of the... 7 Agriculture 5 2010-01-01 2010-01-01 false Bonded release. 356.5 Section 356.5 Agriculture..., DEPARTMENT OF AGRICULTURE FORFEITURE PROCEDURES § 356.5 Bonded release. (a) The Deputy Administrator may...

[Study on preparation and release mechanism of effervescent osmotic pump tablet of compound Danshen].

PubMed

Xue, Li'an; Li, Yuanbo; Guo, Dandan; Yin, Jianhua; Liu, Yanchun; Hou, Shixiang

2009-04-01

To prepare effervescent osmotic pump tablet (EOPTs) according to the rhythm of coronary heart disease based on efficacy material and the mechanism of compound Danshen and to study the mechanism of drug released of that tablets. Since compound Danshen consist of compounds with polyphenolic groups or carboxyl groups, such as phenolic acids, flavonoids, and triterpenoids that they were acidic. EOPTs were prepared from tablet cores which containing NaHCO3 as effervescent, NaCL and manitol as osmotic agents, HPMC as retarding agents coating with CA membrane. And study the mechanism of drug released according to the change of tablet osmotic pressure. The results of in vitro experiments showed that no difference was observed among the profiles of Danshensu, protocatechuic aldehyde, ginsenoside Rg1, Rb1, notoginsenoside R1 release EOPTs. The drug was completely released from the device with a zero-order release rate over 12 h. EOPTs are Successfully obtained EOPT which the drug is released from the device over 12 h and the release mechanism of EOPTs is explained.

Mold Allergy: Proper Humidifier Care

MedlinePlus

... Training Home Conditions Allergy Allergy Overview Allergy Allergens Mold Allergy Proper Humidifier Care Proper Humidifier Care Make ... neglected humidifier can be a major source of mold and mold spores. Learn how to keep a ...

Molds

MedlinePlus

Molds are fungi that can be found both outdoors and indoors. They grow best in warm, damp and humid conditions. If ... spots in your house, you will probably get mold. Molds can cause health problems. Inhaling or touching ...

Linear Epitopes of Paracoccidioides brasiliensis and Other Fungal Agents of Human Systemic Mycoses As Vaccine Candidates

PubMed Central

Travassos, Luiz R.; Taborda, Carlos P.

2017-01-01

Dimorphic fungi are agents of systemic mycoses associated with significant morbidity and frequent lethality in the Americas. Among the pathogenic species are Paracoccidioides brasiliensis and Paracoccidioides lutzii, which predominate in South America; Histoplasma capsulatum, Coccidioides posadasii, and Coccidioides immitis, and the Sporothrix spp. complex are other important pathogens. Associated with dimorphic fungi other important infections are caused by yeast such as Candida spp. and Cryptococcus spp. or mold such as Aspergillus spp., which are also fungal agents of deadly infections. Nowadays, the actual tendency of therapy is the development of a pan-fungal vaccine. This is, however, not easy because of the complexity of eukaryotic cells and the particularities of different species and isolates. Albeit there are several experimental vaccines being studied, we will focus mainly on peptide vaccines or epitopes of T-cell receptors inducing protective fungal responses. These peptides can be carried by antibody inducing β-(1,3)-glucan oligo or polysaccharides, or be mixed with them for administration. The present review discusses the efficacy of linear peptide epitopes in the context of antifungal immunization and vaccine proposition. PMID:28344577

A description of the standardized measurement procedures and recommended threshold limit values for biological hazards in Germany.

PubMed

Rieger, M A; Lohmeyer, M; Nübling, M; Neuhaus, S; Diefenbach, H; Hofmann, F

2005-05-01

On the basis of EU directives 89/391/EEC (to encourage improvements in the safety and health of workers at work) and 2000/54/EC (on the protection of workers from risks related to exposure to biological agents at work), biological hazards at work have to be assessed and preventive measures have to be introduced in all member states of the EU. In Germany, national legislation (Biological Agents Ordinance - BioStoffV and Technical Rules on Biological Agents, TRBA) and recommendations of workers' compensation boards define standardized methods for the assessment of airborne mold, bacteria, and endotoxins. This article describes policies and practices in Germany for measurement of airborne bioaerosols and for interpretation of measurements relative to the standards. As an example, methods and results of measurements in agriculture are shown. The standardized measurement procedures proved suitable for use in livestock buildings. The results of the exploratory measurements in different livestock buildings confirmed the often high concentrations of airborne biological hazards in agriculture that are reported in the literature.

Molds in the Environment

MedlinePlus

... visit this page: About CDC.gov . Mold Cleanup & Remediation Homeowner’s and Renter’s Guide to Mold Cleanup After ... Home or Building with Mold Damage Prevention and Remediation Strategies for the Control and Removal of Fungal ...

Soft lithography of ceramic microparts using wettability-tunable poly(dimethylsiloxane) (PDMS) molds

NASA Astrophysics Data System (ADS)

Su, Bo; Zhang, Aijun; Meng, Junhu; Zhang, Zhaozhu

2016-07-01

Green alumina microparts were fabricated from a high solid content aqueous suspension by microtransfer molding using air plasma-treated poly(dimethylsiloxane) (PDMS) molds. The wettability of the air plasma-treated PDMS molds spontaneously changed between the hydrophilic and hydrophobic states during the process. Initial hydrophilicity of the air plasma-treated PDMS molds significantly improved the flowability of the concentrated suspension. Subsequent hydrophobic recovery of the air plasma-treated PDMS molds enabled a perfect demolding of the green microparts. Consequently, defect-free microchannel parts of 60 μm and a micromixer with an area of several square centimeters were successfully fabricated. In soft lithography, tuning the wetting behavior of PDMS molds has a great effect on the quality of ceramic microparts. Using wettability-tunable PDMS molds has great potential in producing complex-shaped and large-area ceramic microparts and micropatterns.

Study of parameters in precision optical glass molding

NASA Astrophysics Data System (ADS)

Ni, Ying; Wang, Qin-hua; Yu, Jing-chi

2010-10-01

Precision glass compression molding is an attractive approach to manufacture small precision optics in large volume over traditional manufacturing techniques because of its advantages such as lower cost, faster time to market and being environment friendly. In order to study the relationship between the surface figures of molded lenses and molding process parameters such as temperature, pressure, heating rate, cooling rate and so on, we present some glass compression molding experiments using same low Tg (transition temperature) glass material to produce two different kinds of aspheric lenses by different molding process parameters. Based on results from the experiments, we know the major factors influencing surface figure of molded lenses and the changing range of these parameters. From the knowledge we could easily catch proper molding parameters which are suitable for aspheric lenses with diameter from 10mm to 30mm.

Fabrication of spherical microlens array by combining lapping on silicon wafer and rapid surface molding

NASA Astrophysics Data System (ADS)

Liu, Xiaohua; Zhou, Tianfeng; Zhang, Lin; Zhou, Wenchen; Yu, Jianfeng; Lee, L. James; Yi, Allen Y.

2018-07-01

Silicon is a promising mold material for compression molding because of its properties of hardness and abrasion resistance. Silicon wafers with carbide-bonded graphene coating and micro-patterns were evaluated as molds for the fabrication of microlens arrays. This study presents an efficient but flexible manufacturing method for microlens arrays that combines a lapping method and a rapid molding procedure. Unlike conventional processes for microstructures on silicon wafers, such as diamond machining and photolithography, this research demonstrates a unique approach by employing precision steel balls and diamond slurries to create microlenses with accurate geometry. The feasibility of this method was demonstrated by the fabrication of several microlens arrays with different aperture sizes and pitches on silicon molds. The geometrical accuracy and surface roughness of the microlens arrays were measured using an optical profiler. The measurement results indicated good agreement with the optical profile of the design. The silicon molds were then used to copy the microstructures onto polymer substrates. The uniformity and quality of the samples molded through rapid surface molding were also assessed and statistically quantified. To further evaluate the optical functionality of the molded microlens arrays, the focal lengths of the microlens arrays were measured using a simple optical setup. The measurements showed that the microlens arrays molded in this research were compatible with conventional manufacturing methods. This research demonstrated an alternative low-cost and efficient method for microstructure fabrication on silicon wafers, together with the follow-up optical molding processes.

Precision molding of advanced glass optics: innovative production technology for lens arrays and free form optics

NASA Astrophysics Data System (ADS)

Pongs, Guido; Bresseler, Bernd; Bergs, Thomas; Menke, Gert

2012-10-01

Today isothermal precision molding of imaging glass optics has become a widely applied and integrated production technology in the optical industry. Especially in consumer electronics (e.g. digital cameras, mobile phones, Blu-ray) a lot of optical systems contain rotationally symmetrical aspherical lenses produced by precision glass molding. But due to higher demands on complexity and miniaturization of optical elements the established process chain for precision glass molding is not sufficient enough. Wafer based molding processes for glass optics manufacturing become more and more interesting for mobile phone applications. Also cylindrical lens arrays can be used in high power laser systems. The usage of unsymmetrical free-form optics allows an increase of efficiency in optical laser systems. Aixtooling is working on different aspects in the fields of mold manufacturing technologies and molding processes for extremely high complex optical components. In terms of array molding technologies, Aixtooling has developed a manufacturing technology for the ultra-precision machining of carbide molds together with European partners. The development covers the machining of multi lens arrays as well as cylindrical lens arrays. The biggest challenge is the molding of complex free-form optics having no symmetrical axis. A comprehensive CAD/CAM data management along the entire process chain is essential to reach high accuracies on the molded lenses. Within a national funded project Aixtooling is working on a consistent data handling procedure in the process chain for precision molding of free-form optics.

Remelt Ingot Production Technology

NASA Astrophysics Data System (ADS)

Grandfield, J. F.

The technology related to the production of remelt ingots (small ingots, sows and T-Bar) is reviewed. Open mold conveyors, sow casting, wheel and belt casting and VDC and HDC casting are described and compared. Process economics, capacity, product quality and process problems are listed. Trends in casting machine technology such as longer open mold conveyor lines are highlighted. Safety issues related to the operation of these processes are discussed. The advantages and disadvantages of the various machine configurations and options e.g. such as dry filling with the mold out of water and wet filling with the mold in water for open mould conveyors are discussed. The effect of mold design on machine productivity, mold cracking and mold life is also examined.

Transfer molding of PMR-15 polyimide resin

NASA Technical Reports Server (NTRS)

Reardon, J. P.; Moyer, D. W.; Nowak, B. E.

1985-01-01

Transfer molding is an economically viable method of producing small shapes of PMR-15 polyimide. It is shown that with regard to flexural, compressive, and tribological properties transfer-molded PMR-15 polyimide is essentially equivalent to PMR-15 polyimide produced by the more common method of compression molding. Minor variations in anisotropy are predictable effects of molding design and secondary finishing operations.

Method and composition for molding low-density desiccant syntactic-foam articles

DOEpatents

Not Available

1981-12-07

These and other objects of the invention are achieved by a process for molding to size a desiccant syntactic foam article having a density of 0.2 to 0.9 g/cc and a moisture capacity of 1 to 12% by weight, comprising the steps of: charging a mold with a powdery mixture of an activated desiccant, microspheres and a thermosetting resin, the amount of the desiccant being sufficient to provide the required moisture capacity, and the amounts of the microspheres and resin being such that the microspheres/desiccant volume fraction exceeds the packing factor by an amount sufficient to substantially avoid shrinkage without causing excessively high molding pressures; covering the mold and heating the covered mold to a temperature and for an amount of time sufficient to melt the resin; and tightly closing the mold and heating the closed mold to a temperature and for an amount of time sufficient to cure the resin, and removing the resultant desiccant syntactic foam article from the mold. In a composition of matter aspect, the present invention provides desiccant syntactic foam articles, and a composition of matter for use in molding the same.

Selection of antifungal protein-producing molds from dry-cured meat products.

PubMed

Acosta, Raquel; Rodríguez-Martín, Andrea; Martín, Alberto; Núñez, Félix; Asensio, Miguel A

2009-09-30

To control unwanted molds in dry-cured meats it is necessary to allow the fungal development essential for the desired characteristics of the final product. Molds producing antifungal proteins could be useful to prevent hazards due to the growth of mycotoxigenic molds. The objective has been to select Penicillium spp. that produce antifungal proteins against toxigenic molds. To obtain strains adapted to these products, molds were isolated from dry-cured ham. A first screening with 281 isolates by the radial inhibition assay revealed that 166 were active against some of the toxigenic P. echinulatum, P. commune, and Aspergillusniger used as reference molds. The activity of different extracts from cultured medium was evaluated by a microspectroscopic assay. Molds producing active chloroform extracts were eliminated from further consideration. A total of 16 Penicillium isolates were screened for antifungal activity from both cell-free media and the aqueous residues obtained after chloroform extraction. The cell-free media of 10 isolates that produced a strong inhibition of the three reference molds were fractionated by FPLC on a cationic column. For protein purification, the fractions of the three molds that showed high inhibitory activity were further chromatographed on a gel filtration column, and the subfractions containing the highest absorbance peaks were assayed against the most sensitive reference molds. One subfraction each from strains AS51D and RP42C from Penicilliumchrysogenum confirmed the inhibitory activity against the reference molds. SDS-PAGE revealed a single band from each subfraction, with estimated molecular masses of 37kDa for AS51D and 9kDa for RP42C. Although further characterisation is required, both these proteins and the producing strains can be of interest to control unwanted molds on foods.

Antibodies to molds and satratoxin in individuals exposed in water-damaged buildings.

PubMed

Vojdani, Aristo; Thrasher, Jack D; Madison, Roberta A; Gray, Michael R; Heuser, Gunnar; Campbell, Andrew W

2003-07-01

Immunoglobulin (Ig)A, IgM, and IgG antibodies against Penicillium notatum, Aspergillus niger, Stachybotrys chartarum, and satratoxin H were determined in the blood of 500 healthy blood donor controls, 500 random patients, and 500 patients with known exposure to molds. The patients were referred to the immunological testing laboratory for health reasons other than mold exposure, or for measurement of mold antibody levels. Levels of IgA, IgM, and IgG antibodies against molds were significantly greater in the patients (p < 0.001 for all measurements) than in the controls. However, in mold-exposed patients, levels of these antibodies against satratoxin differed significantly for IgG only (p < 0.001), but not for IgM or IgA. These differences in the levels of mold antibodies among the 3 groups were confirmed by calculation of z score and by Scheffé's significant difference tests. A general linear model was applied in the majority of cases, and 3 different subsets were formed, meaning that the healthy control groups were different from the random patients and from the mold-exposed patients. These findings indicated that mold exposure was more common in patients who were referred for immunological evaluation than it was in healthy blood donors. The detection of antibodies to molds and satratoxin H likely resulted from antigenic stimulation of the immune system and the reaction of serum with specially prepared mold antigens. These antigens, which had high protein content, were developed in this laboratory and used in the enzyme-linked immunosorbent assay (ELISA) procedure. The authors concluded that the antibodies studied are specific to mold antigens and mycotoxins, and therefore could be useful in epidemiological and other studies of humans exposed to molds and mycotoxins.

Mold and Indoor Air Quality in Schools

MedlinePlus

... Centers Mold Contact Us Share Mold and Indoor Air Quality in Schools Mold and Moisture in Schools Webinar ... premier resource on this issue is the Indoor Air Quality Tools for Schools kit. Our schools-related resources ...

Supersoft lithography: Candy-based fabrication of soft silicone microstructures

PubMed Central

Moraes, Christopher; Labuz, Joseph M.; Shao, Yue; Fu, Jianping; Takayama, Shuichi

2015-01-01

We designed a fabrication technique able to replicate microstructures in soft silicone materials (E < 1 kPa). Sugar-based ‘hard candy’ recipes from the confectionery industry were modified to be compatible with silicone processing conditions, and used as templates for replica molding. Microstructures fabricated in soft silicones can then be easily released by dissolving the template in water. We anticipate that this technique will be of particular importance in replicating physiologically soft, microstructured environments for cell culture, and demonstrate a first application in which intrinsically soft microstructures are used to measure forces generated by fibroblast-laden contractile tissues. PMID:26245893

Supersoft lithography: candy-based fabrication of soft silicone microstructures.

PubMed

Moraes, Christopher; Labuz, Joseph M; Shao, Yue; Fu, Jianping; Takayama, Shuichi

2015-01-01

We designed a fabrication technique able to replicate microstructures in soft silicone materials (E < 1 kPa). Sugar-based 'hard candy' recipes from the confectionery industry were modified to be compatible with silicone processing conditions, and used as templates for replica molding. Microstructures fabricated in soft silicones can then be easily released by dissolving the template in water. We anticipate that this technique will be of particular importance in replicating physiologically soft, microstructured environments for cell culture, and demonstrate a first application in which intrinsically soft microstructures are used to measure forces generated by fibroblast-laden contractile tissues.

Turning Science Results into News

NASA Astrophysics Data System (ADS)

Wanjek, Christopher

2006-09-01

Do you want to get into the New York Times? Aside from writing an angry letter or robbing a bank, getting into the news (with your science result) requires a well-crafted press release. Reaching out to reporters is very different from reaching out to fellow scientists. Scientific significance is not the same as newsworthiness, but many science results can be molded into interesting stories that reporters can relate to their audience. This presentation will present examples of science stories that made it big and some that flopped. We will also examine what makes a story attractive to newspaper and magazine editors.

Pulsatile release of biomolecules from polydimethylsiloxane (PDMS) chips with hydrolytically degradable seals.

PubMed

Intra, Janjira; Glasgow, Justin M; Mai, Hoang Q; Salem, Aliasger K

2008-05-08

We demonstrate, for the first time, a robust novel polydimethylsiloxane (PDMS) chip that can provide controlled pulsatile release of DNA based molecules, proteins and oligonucleotides without external stimuli or triggers. The PDMS chip with arrays of wells was constructed by replica molding. Poly(lactic acid-co-glycolic acid) (PLGA) polymer films of varying composition and thickness were used as seals to the wells. The composition, molecular weight and thickness of the PLGA films were all parameters used to control the degradation rate of the seals and therefore the release profiles. Degradation of the films followed the PLGA composition order of 50:50 PLGA>75:25 PLGA>85:15 PLGA at all time-points beyond week 1. Scanning electron microscopy images showed that films were initially smooth, became porous and ruptured as the osmotic pressure pushed the degrading PLGA film outwards. Pulsatile release of DNA was controlled by the composition and thickness of the PLGA used to seal the well. Transfection experiments in a model Human Embryonic Kidney 293 (HEK293) cell line showed that plasmid DNA loaded in the wells was functional after pulsatile release in comparison to control plasmid DNA at all time-points. Thicker films degraded faster than thinner films and could be used to fine-tune the release of DNA over day length periods. Finally the PDMS chip was shown to provide repeated sequential release of CpG oligonucleotides and a model antigen, Ovalbumin (OVA), indicating significant potential for this device for vaccinations or applications that require defined complex release patterns of a variety of chemicals, drugs and biomolecules.

Direct micropatterning of polymer materials by ice mold

NASA Astrophysics Data System (ADS)

Yu, Xinhong; Xing, Rubo; Luan, Shifang; Wang, Zhe; Han, Yanchun

2006-10-01

Micropatterning of functional polymer materials by micromolding in capillaries (MIMIC) with ice mold is reported in this paper. Ice mold was selected due to its thaw or sublimation. Thus, the mold can be easily removed. Furthermore, the polymer solution did not react with, swell, or adhere to the ice mold, so the method is suitable for many kinds of materials (such as P3HT, PMMA Alq 3/PVK, PEDOT: PSS, PS, P2VP, etc.). Freestanding polymer microstructures, binary polymer pattern, and microchannels have been fabricated by the use of ice mold freely.

Static Mixer for Heat Transfer Enhancement for Mold Cooling Application

NASA Astrophysics Data System (ADS)

Becerra, Rodolfo; Barbosa, Raul; Lee, Kye-Hwan; Park, Younggil

Injection molding is the process by which a material is melted in a barrel and then it is injected through a nozzle in the mold cavity. When it cools down, the material solidifies into the shape of the cavity. Typical injection mold has cooling channels to maintain constant mold temperature during injection molding process. Even and constant temperature throughout the mold are very critical for a part quality and productivity. Conformal cooling improves the quality and productivity of injection molding process through the implementation of cooling channels that ``conform'' to the shape of the molded part. Recent years, the use of conformal cooling increases with advance of 3D printing technology such as Selective Laser Melting (SLM). Although it maximizes cooling, material and dimension limitations make SLM methods highly expensive. An alternative is the addition of static mixers in the molds with integrated cooling channels. A static mixer is a motionless mixing device that enhances heat transfer by producing improved flow mixing in the pipeline. In this study, the performance of the cooling channels will be evaluated with and without static mixers, by measuring temperature, pressure drop, and flow rate. The following question is addressed: Can a static mixer effectively enhance heat transfer for mold cooling application processes? This will provide insight on the development of design methods and guidelines that can be used to increase cooling efficiency at a lower cost.

Interactive Mold House Tour

EPA Pesticide Factsheets

Get a quick glimpse of some of the most important ways to protect your home from mold by this interactive tour of the Mold House. Room-by-room, you'll learn about common mold issues and how to address them.

Direct molding of pavement tiles made of ground tire rubber

NASA Astrophysics Data System (ADS)

Quadrini, Fabrizio; Gagliardi, Donatella; Tedde, Giovanni Matteo; Santo, Loredana; Musacchi, Ettore

2016-10-01

Large rubber products can be molded by using only ground tire rubber (GTR) without any additive or binder due to a new technology called "direct molding". Rubber granules and powders from tire recycling are compression molded at elevated temperatures and pressures. The feasibility of this process was clearly shown in laboratory but the step to the industrial scale was missing. Thanks to an European Project (SMART "Sustainable Molding of Articles from Recycled Tires") this step has been made and some results are reported in this study. The press used for compression molding is described. Some tests were made to measure the energy consumption so as to evaluate costs for production in comparison with conventional technologies for GTR molding (by using binders). Results show that 1 m2 tiles can be easily molded with several thicknesses in a reasonable low time. Energy consumption is higher than conventional technologies but it is lower than the cost for binders.

Effect of Reclamation on the Skin Layer of Ductile Iron Cast in Furan Molds

NASA Astrophysics Data System (ADS)

Dańko, R.; Holtzer, M.; Górny, M.; Żymankowska-Kumon, S.

2013-11-01

The paper presents the results of investigations of the influence of the quality of molding sand with furan resin hardened by paratoluenesulfonic acid, on the formation of microstructure and surface quality of ductile iron castings. Within the studies different molding sands were used: molding sand prepared with fresh sand and molding sands prepared with reclaimed sands of a different purification degree, determined by the ignition loss value. Various concentrations of sulfur and nitrogen in the sand molds as a function of the ignition loss were shown in the paper. A series of experimental melts of ductile iron in molds made of molding sand characterized by different levels of surface-active elements (e.g., sulfur) and different gas evolution rates were performed. It was shown that there exists a significant effect of the quality of the sand on the formation of the graphite degeneration layer.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howell, Caitlin; Vu, Thy L.; Lin, Jennifer J.

Inspired by the long-term effectiveness of living antifouling materials, we have developed a method for the selfreplenishment of synthetic biofouling-release surfaces. These surfaces are created by either molding or directly embedding 3D vascular systems into polydimethylsiloxane (PDMS) and filling them with a silicone oil to generate a nontoxic oil-infused material. When replenished with silicone oil from an outside source, these materials are capable of self-lubrication and continuous renewal of the interfacial fouling-release layer. Under accelerated lubricant loss conditions, fully infused vascularized samples retained significantly more lubricant than equivalent nonvascularized controls. Tests of lubricant-infused PDMS in static cultures of the infectiousmore » bacteria Staphylococcus aureus and Escherichia coli as well as the green microalgae Botryococcus braunii, Chlamydomonas reinhardtii, Dunaliella salina, and Nannochloropsis oculata showed a significant reduction in biofilm adhesion compared to PDMS and glass controls containing no lubricant. Further experiments on vascularized versus nonvascularized samples that had been subjected to accelerated lubricant evaporation conditions for up to 48 h showed significantly less biofilm adherence on the vascularized surfaces. These results demonstrate the ability of an embedded lubricant-filled vascular network to improve the longevity of fouling-release surfaces.« less

Halloysite clay nanotubes for controlled delivery of chemically active agents

NASA Astrophysics Data System (ADS)

Abdullayev, Elshard

In this work we explored the capabilities of halloysite nanotubes as capsules for encapsulation and controlled delivery of the chemically and biologically active substances. Halloysite is a two-layered aluminosilicate which has a predominantly hollow tubular structure in the submicron range and is chemically similar to kaolinite [1, 2]. In the first section of this work, we analyzed the structure of the halloysite nanotubes as well as its capability to encapsulate and deliver biologically and chemically active agents, similarities and differences between release characteristics of different agents and how these differences relate with their chemical structure. Models were used to describe the release characteristics of the active agents. Study of the interaction between loaded agents and halloysite nanotubes provides better understanding of the release characteristics of the loaded agents and how halloysite can be implemented for technological and medical applications. The second part of the work deals with self-healing coatings produced on the basis of halloysite nanotubes loaded with corrosion inhibitors. Self-healing coatings are one of the effective methods to protect metals from corrosion and deterioration. The difference between self-healing coatings and the usual coatings is the ability of the first to recover after the formation of the damages due to external or internal stresses. High efficiency of the self- healing coatings produced by halloysite nanotubes were demonstrated on 110 Copper alloys and 2024 aluminum alloys. Controlled delivery of the corrosion inhibitors with additional encapsulation of the halloysite nanotubes by synthesizing stoppers at tube endings was also demonstrated. Additional encapsulation of the halloysite nanotubes may be necessary when slow release of the loaded agents is required or rapid convection of the liquid in the surrounding environment takes place (since this may cause rapid release of the loaded agents without additional encapsulation). The third part of this work deals with pharmaceutical applications of the halloysite nanotubes. Toxicity analysis was performed by using MCF-7 and HeLa cells since this is the main issue to be considered before using halloysite for any technological and medical applications. Halloysite nanotubes were readily taken up by the cells and cells survived for a reasonably long time after uptake indicating the biocompatible nature of the halloysite nanotubes. The possibility to encapsulate glycerol, a skin moisturizing agent, was also demonstrated for pharmaceutical applications. It was shown that halloysite has a huge capability for encapsulating a wide range of pharmaceuticals and effectively deliver over a long time range which may increase the quality of pharmaceutical products.

Surface Monitoring of CFRP Structures for Adhesive Bonding

NASA Technical Reports Server (NTRS)

Ledesma, Rodolfo; Palmieri, Frank L.; Yost, William T.; Connell, John W.; Fitz-Gerald, James M.

2017-01-01

Adhesive bonding of composite materials requires reliable monitoring and detection of surface contaminants to assure robust and durable bonded structures. Surface treatment and effective monitoring prior to bonding is essential in order to obtain a surface free from contaminants that may degrade structural performance. Two techniques which monitor the effectiveness of the laser surface treatment of carbon fiber reinforced polymer (CFRP) materials are being investigated: laser induced breakdown spectroscopy (LIBS) and optically stimulated electron emission (OSEE). The applicability of LIBS to detect silicone contaminants on CFRP composites is studied using 35 ns Nd:YAG laser pulses at 355 nm with a pulse energy of 45 mJ. The LIBS regime in which pulse energies are < 100 mJ is referred to as mLIBS. CFRP surfaces were contaminated with polydimethylsiloxane (PDMS), a major component of silicone based mold release agents. The presence of PDMS is found by inspecting the Si I emission line at 288.2 nm. Untreated CFRP samples and CFRP contaminated with PDMS were tested. The PDMS areal density ranged from 0.36 Â+/- 0.04 to 0.51 Â+/- 0.16 mg/cm2. The results demonstrate the successful detection of PDMS on CFRP using mLIBS. In addition, OSEE was used to measure CFRP surface cleanliness pre- and post-treatment by laser ablation on specimens contaminated with PDMS coatings from 8 nm to 1311 nm in thickness. The results showed a significant increase in the OSEE photocurrent after laser surface treatment.

THE IMPORTANCE OF RISK COMMUNICATION

EPA Science Inventory

The goal of environmental and public health is to reduce the health risks associated with microbial and toxic agents in the environment, and also to agents of injury. There have generally been three approaches to managing these risks: first, control releases of the agent to the e...

Development of a poly (ether urethane) system for the controlled release of two novel anti-biofilm agents based on gallium or zinc and its efficacy to prevent bacterial biofilm formation

PubMed Central

Ma, Hongyan; Darmawan, Erica T.; Zhang, Min; Zhange, Lei; Bryers, James D.

2013-01-01

Traditional antibiotic therapy to control medical device-based infections typically fails to clear biofilm infections and may even promote the evolution of antibiotic resistant species. We report here the development of two novel antibiofilm agents; gallium (Ga) or zinc (Zn) complexed with protoporphyrin IX (PP) or mesoprotoporphyrin IX (MP) that are both highly effective in negating suspended bacterial growth and biofilm formation. These chelated gallium or zinc complexes act as iron siderophore analogs, surplanting the natural iron uptake of most bacteria. Poly (ether urethane) (PEU; Biospan®) polymer films were fabricated for the controlled sustained release of the Ga- or Zn-complexes, using an incorporated pore-forming agent, poly (ethylene glycol) (PEG). An optimum formulation containing 8% PEG (MW=1450) in the PEU polymer effectively sustained drug release for at least 3 months. All drug-loaded PEU films exhibited in vitro ≥ 90% reduction of Gram-positive (Staphylococcus epidermidis) and Gram-negative (Pseudomonas aeruginosa) bacteria in both suspended and biofilm culture versus the negative control PEU films releasing nothing. Cytotoxicity and endotoxin evaluation demonstrated no adverse responses to the Ga- or Zn-complex releasing PEU films. Finally, in vivo studies further substantiate the anti-biofilm efficacy of the PEU films releasing Ga- or Zn- complexes. PMID:24140747

Development of a poly(ether urethane) system for the controlled release of two novel anti-biofilm agents based on gallium or zinc and its efficacy to prevent bacterial biofilm formation.

PubMed

Ma, Hongyan; Darmawan, Erica T; Zhang, Min; Zhang, Lei; Bryers, James D

2013-12-28

Traditional antibiotic therapy to control medical device-based infections typically fails to clear biofilm infections and may even promote the evolution of antibiotic resistant species. We report here the development of two novel antibiofilm agents; gallium (Ga) or zinc (Zn) complexed with protoporphyrin IX (PP) or mesoprotoporphyrin IX (MP) that are both highly effective in negating suspended bacterial growth and biofilm formation. These chelated gallium or zinc complexes act as iron siderophore analogs, supplanting the natural iron uptake of most bacteria. Poly (ether urethane) (PEU; Biospan®) polymer films were fabricated for the controlled sustained release of the Ga- or Zn-complexes, using an incorporated pore-forming agent, poly(ethylene glycol) (PEG). An optimum formulation containing 8% PEG (MW=1450) in the PEU polymer effectively sustained drug release for at least 3months. All drug-loaded PEU films exhibited in vitro ≥ 90% reduction of Gram-positive (Staphylococcus epidermidis) and Gram-negative (Pseudomonas aeruginosa) bacteria in both suspended and biofilm culture versus the negative control PEU films releasing nothing. Cytotoxicity and endotoxin evaluation demonstrated no adverse responses to the Ga- or Zn-complex releasing PEU films. Finally, in vivo studies further substantiate the anti-biofilm efficacy of the PEU films releasing Ga- or Zn- complexes. © 2013.

Insulin secretion from isolated rat islets induced by the novel hypoglycemic agent A-4166, a derivative of D-phenylalanine.

PubMed

Tsukuda, K; Sakurada, M; Niki, I; Oka, Y; Kikuchi, M

1998-01-01

A derivative of D-phenylalanine, A-4166, reportedly evokes a more rapid and short-lived hypoglycemic action in vivo than any of the currently available sulfonylureas. This novel oral hypoglycemic agent is structurally different from sulfonylureas. Therefore, studies were designed to elucidate the mechanisms by which A-4166 stimulates insulin secretion. Insulin release from incubated or perifused rat islets was dose-dependently stimulated by 10 to 200 mumol/l A-4166, in the presence of 2.8 mmol/l glucose. Both A-4166 and tolbutamide evoke a prompt rise in insulin secretion followed by a sustained gradually decreasing release from perfused islets in the presence of low glucose, although A-4166 appeared to be more sensitive than tolbutamide to subthreshold glucose concentration. Diazoxide abolished the initial release and blunted sustained release. Removing calcium from the perifusate abolished insulin release within 15 minutes. A-4166 inhibited [3H]-glibenclamide binding to HIT cell membranes and 86Rb efflux from ATP-depleted or diazoxide-treated cells. These results suggest that the insulin release induced by A-4166 is relevant to this agent occupying the tolbutamide binding sites. Therefore, one possible mechanism accounting for the more rapid and short-lived hypoglycemic action of A-4166 in vivo, as compared with tolbutamide, may involve the reported differences in the bioavailability of A-4166.

Method of reusably sealing a silicone rubber vacuum bag to a mold for composite manufacture

NASA Technical Reports Server (NTRS)

Steinbach, John (Inventor)

1989-01-01

A silicone rubber vacuum bag for use in composite article manufacture is reusably sealed to a mold, without mechanical clamping means. The mold-mating portion of the bag is primed with a silicone rubber adhesive, which is cured thereto, and a layer of semiadhesive sealer is applied between the primed mold-mating portion of the bag and the mold.

56. ORIGINAL MOLDS. THE MORAVIAN POTTERY AND TILE WORKS HAS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

56. ORIGINAL MOLDS. THE MORAVIAN POTTERY AND TILE WORKS HAS APPROXIMATELY 6,000 PLASTER MOLDS OF VARIOUS TYPES, INCLUDING THE DEEP CAVITY MOLDS IN THE CENTER OF THE PHOTOGRAPH. THESE MOLDS PRODUCED ALLEGORICAL FIGURES TO BE INSTALLED AROUND THE CORNICES OF PUBLIC SCHOOLS. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

Evacuated, displacement compression mold. [of tubular bodies from thermosetting plastics

NASA Technical Reports Server (NTRS)

Heier, W. C. (Inventor)

1974-01-01

A process of molding long thin-wall tubular bodies from thermosetting plastic molding compounds is described wherein the tubular body lengths may be several times the diameters. The process is accomplished by loading a predetermined quantity of molding compound into a female mold cavity closed at one end by a force mandrel. After closing the other end of the female mold with a balance mandrel, the loaded cavity is evacuated by applying a vacuum of from one-to-five mm pressure for a period of fifteen-to-thirty minutes. The mold temperature is raised to the minimum temperature at which the resin constituent of the compound will soften or plasticize and a pressure of 2500 psi is applied.

Mathematical modeling of the process of filling a mold during injection molding of ceramic products

NASA Astrophysics Data System (ADS)

Kulkov, S. N.; Korobenkov, M. V.; Bragin, N. A.

2015-10-01

Using the software package Fluent it have been predicted of the filling of a mold in injection molding of ceramic products is of great importance, because the strength of the final product is directly related to the presence of voids in the molding, making possible early prediction of inaccuracies in the mold prior to manufacturing. The calculations were performed in the formulation of mathematical modeling of hydrodynamic turbulent process of filling a predetermined volume of a viscous liquid. The model used to determine the filling forms evaluated the influence of density and viscosity of the feedstock, and the injection pressure on the mold filling process to predict the formation of voids in the area caused by the shape defect geometry.

27 CFR 26.80 - Deferred payment of tax-release of spirits.

Code of Federal Regulations, 2010 CFR

2010-04-01

... indicate on TTB Form 5110.51. The revenue agent shall then execute his report of release on the TTB Form...-release of spirits. 26.80 Section 26.80 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... tax—release of spirits. (a) Action by proprietor. Where the proprietor has furnished bond on TTB Form...

Engineered collagen hydrogels for the sustained release of biomolecules and imaging agents: promoting the growth of human gingival cells.

PubMed

Choi, Jonghoon; Park, Hoyoung; Kim, Taeho; Jeong, Yoon; Oh, Myoung Hwan; Hyeon, Taeghwan; Gilad, Assaf A; Lee, Kwan Hyi

2014-01-01

We present here the in vitro release profiles of either fluorescently labeled biomolecules or computed tomography contrast nanoagents from engineered collagen hydrogels under physiological conditions. The collagen constructs were designed as potential biocompatible inserts into wounded human gingiva. The collagen hydrogels were fabricated under a variety of conditions in order to optimize the release profile of biomolecules and nanoparticles for the desired duration and amount. The collagen constructs containing biomolecules/nanoconstructs were incubated under physiological conditions (ie, 37°C and 5% CO2) for 24 hours, and the release profile was tuned from 20% to 70% of initially loaded materials by varying the gelation conditions of the collagen constructs. The amounts of released biomolecules and nanoparticles were quantified respectively by measuring the intensity of fluorescence and X-ray scattering. The collagen hydrogel we fabricated may serve as an efficient platform for the controlled release of biomolecules and imaging agents in human gingiva to facilitate the regeneration of oral tissues.

Engineered collagen hydrogels for the sustained release of biomolecules and imaging agents: promoting the growth of human gingival cells

PubMed Central

Choi, Jonghoon; Park, Hoyoung; Kim, Taeho; Jeong, Yoon; Oh, Myoung Hwan; Hyeon, Taeghwan; Gilad, Assaf A; Lee, Kwan Hyi

2014-01-01

We present here the in vitro release profiles of either fluorescently labeled biomolecules or computed tomography contrast nanoagents from engineered collagen hydrogels under physiological conditions. The collagen constructs were designed as potential biocompatible inserts into wounded human gingiva. The collagen hydrogels were fabricated under a variety of conditions in order to optimize the release profile of biomolecules and nanoparticles for the desired duration and amount. The collagen constructs containing biomolecules/nanoconstructs were incubated under physiological conditions (ie, 37°C and 5% CO2) for 24 hours, and the release profile was tuned from 20% to 70% of initially loaded materials by varying the gelation conditions of the collagen constructs. The amounts of released biomolecules and nanoparticles were quantified respectively by measuring the intensity of fluorescence and X-ray scattering. The collagen hydrogel we fabricated may serve as an efficient platform for the controlled release of biomolecules and imaging agents in human gingiva to facilitate the regeneration of oral tissues. PMID:25429215

Controlled study of mold growth and cleaning procedure on treated and untreated wet gypsum wallboard in an indoor environment.

PubMed

Krause, Michael; Geer, William; Swenson, Lonie; Fallah, Payam; Robbins, Coreen

2006-08-01

The basis for some common gypsum wallboard mold remediation practices was examined. The bottom inch of several gypsum wallboard panels was immersed in bottled drinking water; some panels were coated and others were untreated. The panels were examined and tested for a period of 8 weeks. This study investigated: (a) whether mold growth, detectable visually or with tape lift samples, occurs within 1 week on wet gypsum wallboard; (b) the types, timing, and extent of mold growth on wet gypsum wallboard; (c) whether mold growth is present on gypsum wallboard surfaces 6 inches from visible mold growth; (d) whether some commonly used surface treatments affect the timing of occurrence and rate of mold growth; and (e) if moldy but dried gypsum wallboard can be cleaned with simple methods and then sealed with common surface treatments so that residual mold particles are undetectable with typical surface sampling techniques. Mold growth was not detected visually or with tape lift samples after 1 week on any of the wallboard panels, regardless of treatment, well beyond the 24-48 hours often mentioned as the incubation period. Growth was detected at 2 weeks on untreated gypsum. Penicillium, Cladosporium, and Acremonium were early colonizers of untreated panels. Aspergillus, Epicoccum, Alternaria, and Ulocladium appeared later. Stachybotrys was not found. Mold growth was not detected more than 6 inches beyond the margin of visible mold growth, suggesting that recommendations to remove gypsum wallboard more than 1 foot beyond visible mold are excessive. The surface treatments resulted in delayed mold growth and reduced the area of mold growth compared with untreated gypsum wallboard. Results showed that simple cleaning of moldy gypsum wallboard was possible to the extent that mold particles beyond "normal trapping" were not found on tape lift samples. Thus, cleaning is an option in some situations where removal is not feasible or desirable. In cases where conditions are not similar to those of this study, or where large areas may be affected, a sample area could be cleaned and tested to verify that the cleaning technique is sufficient to reduce levels to background or normal trapping. These results are generally in agreement with laboratory studies of mold growth on, and cleaning of, gypsum wallboard.

A programmable nanoreplica molding for the fabrication of nanophotonic devices.

PubMed

Liu, Longju; Zhang, Jingxiang; Badshah, Mohsin Ali; Dong, Liang; Li, Jingjing; Kim, Seok-min; Lu, Meng

2016-03-01

The ability to fabricate periodic structures with sub-wavelength features has a great potential for impact on integrated optics, optical sensors, and photovoltaic devices. Here, we report a programmable nanoreplica molding process to fabricate a variety of sub-micrometer periodic patterns using a single mold. The process utilizes a stretchable mold to produce the desired periodic structure in a photopolymer on glass or plastic substrates. During the replica molding process, a uniaxial force is applied to the mold and results in changes of the periodic structure, which resides on the surface of the mold. Direction and magnitude of the force determine the array geometry, including the lattice constant and arrangement. By stretching the mold, 2D arrays with square, rectangular, and triangular lattice structures can be fabricated. As one example, we present a plasmonic crystal device with surface plasmon resonances determined by the force applied during molding. In addition, photonic crystal slabs with different array patterns are fabricated and characterized. This unique process offers the capability of generating various periodic nanostructures rapidly and inexpensively.

Rapid and low-cost prototyping of medical devices using 3D printed molds for liquid injection molding.

PubMed

Chung, Philip; Heller, J Alex; Etemadi, Mozziyar; Ottoson, Paige E; Liu, Jonathan A; Rand, Larry; Roy, Shuvo

2014-06-27

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.

Low Cost Injection Mold Creation via Hybrid Additive and Conventional Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dehoff, Ryan R.; Watkins, Thomas R.; List, III, Frederick Alyious

2015-12-01

The purpose of the proposed project between Cummins and ORNL is to significantly reduce the cost of the tooling (machining and materials) required to create injection molds to make plastic components. Presently, the high cost of this tooling forces the design decision to make cast aluminum parts because Cummins typical production volumes are too low to allow injection molded plastic parts to be cost effective with the amortized cost of the injection molding tooling. In addition to reducing the weight of components, polymer injection molding allows the opportunity for the alternative cooling methods, via nitrogen gas. Nitrogen gas cooling offersmore » an environmentally and economically attractive cooling option, if the mold can be manufactured economically. In this project, a current injection molding design was optimized for cooling using nitrogen gas. The various components of the injection mold tooling were fabricated using the Renishaw powder bed laser additive manufacturing technology. Subsequent machining was performed on the as deposited components to form a working assembly. The injection mold is scheduled to be tested in a projection setting at a commercial vendor selected by Cummins.« less

A programmable nanoreplica molding for the fabrication of nanophotonic devices

PubMed Central

Liu, Longju; Zhang, Jingxiang; Badshah, Mohsin Ali; Dong, Liang; Li, Jingjing; Kim, Seok-min; Lu, Meng

2016-01-01

The ability to fabricate periodic structures with sub-wavelength features has a great potential for impact on integrated optics, optical sensors, and photovoltaic devices. Here, we report a programmable nanoreplica molding process to fabricate a variety of sub-micrometer periodic patterns using a single mold. The process utilizes a stretchable mold to produce the desired periodic structure in a photopolymer on glass or plastic substrates. During the replica molding process, a uniaxial force is applied to the mold and results in changes of the periodic structure, which resides on the surface of the mold. Direction and magnitude of the force determine the array geometry, including the lattice constant and arrangement. By stretching the mold, 2D arrays with square, rectangular, and triangular lattice structures can be fabricated. As one example, we present a plasmonic crystal device with surface plasmon resonances determined by the force applied during molding. In addition, photonic crystal slabs with different array patterns are fabricated and characterized. This unique process offers the capability of generating various periodic nanostructures rapidly and inexpensively. PMID:26925828

Effecting aging time of epoxy molding compound to molding process for integrated circuit packaging

NASA Astrophysics Data System (ADS)

Tachapitunsuk, Jirayu; Ugsornrat, Kessararat; Srisuwitthanon, Warayoot; Thonglor, Panakamon

2017-09-01

This research studied about effecting aging time of epoxy molding compound (EMC) that effect to reliability performance of integrated circuit (IC) package in molding process. Molding process is so important of IC packaging process for protecting IC chip (or die) from temperature and humidity environment using encapsulated EMC. For general molding process, EMC are stored in the frozen at 5°C and left at room temperature at 25 °C for aging time on self before molding of die onto lead frame is 24 hours. The aging time effect to reliability performance of IC package due to different temperature and humidity inside the package. In experiment, aging time of EMC were varied from 0 to 24 hours for molding process of SOIC-8L packages. For analysis, these packages were tested by x-ray and scanning acoustic microscope to analyze properties of EMC with an aging time and also analyzed delamination, internal void, and wire sweep inside the packages with different aging time. The results revealed that different aging time of EMC effect to properties and reliability performance of molding process.

Evaluation of flexural, diametral tensile, and shear bond strength of composite repairs.

PubMed

Imbery, T A; Gray, T; DeLatour, F; Boxx, C; Best, A M; Moon, P C

2014-01-01

Repairing composite restorations may be a more conservative treatment than replacing the entire restoration. The objective of this in vitro study was to determine the best repair method by measuring flexural, diametral tensile, and shear bond strength of repaired composites in which the surfaces were treated with chemical primers (Add & Bond or Silane Bond Enhancer), a bonding agent (Optibond Solo Plus [OBSP]), or mechanical retention with a bonding agent. Filtek Supreme Ultra shade B1B was placed in special molds to fabricate specimens that served to test the flexural, diametral tensile, or shear strength of the inherent resin substrate. The same molds were modified to make specimens for testing repair strength of the resin. Repairs were made immediately or after aging in deionized water at 37°C for seven days. All repair sites were finished with coarse Sof-Lex discs to simulate finishing new restorations or partially removing aged restorations. Repair surfaces were treated with one of the following: 1) phosphoric-acid etching and OBSP; 2) Add & Bond; 3) phosphoric-acid etching, Silane Bond Enhancer, and OBSP; or 4) quarter round bur, phosphoric-acid etching, and OBSP. Specimens were placed back in the original molds to fabricate specimens for diametral tensile or flexural testing or in an Ultradent jig to make specimens for shear bond testing. Composite resin in shade B5B was polymerized against the treated surfaces to make repairs. Two negative control groups for the three testing methods consisted of specimens in which repairs were made immediately or after aging without any surface treatments. Controls and experimental repairs were aged (water 37°C, 24 hours) before flexural, diametral tensile, or shear testing in an Instron Universal testing machine at a crosshead speed of 0.5 mm/min. Experimental flexural repair strengths ranged from 26.4% to 88.6% of the inherent substrate strength. Diametral tensile repair strengths ranged from 40% to 80% of the inherent substrate strength, and shear bond strength repairs ranged from 56% to 102%. Geometric means were statistically analyzed with two-way analysis of variance on their log-transformed values. Significant differences were determined using Tukey honestly significant difference (p<0.05). Depending on the mechanical property being tested, surface treatments produced different results. OBSP produced more consistent results than chemical primers.

Biomediated continuous release phosphate fertilizer

DOEpatents

Goldstein, Alan H.; Rogers, Robert D.

1999-01-01

A composition is disclosed for providing phosphate fertilizer to the root zone of plants. The composition comprises a microorganism capable of producing and secreting a solubilization agent, a carbon source for providing raw material for the microorganism to convert into the solubilization agent, and rock phosphate ore for providing a source of insoluble phosphate that is solubilized by the solubilization agent and released as soluble phosphate. The composition is provided in a physical form, such as a granule, that retains the microorganism, carbon source, and rock phosphate ore, but permits water and soluble phosphate to diffuse into the soil. A method of using the composition for providing phosphate fertilizer to plants is also disclosed.

Release of Membrane-associated Mucins from Ocular Surface Epithelia

PubMed Central

Blalock, Timothy D.; Spurr-Michaud, Sandra J.; Tisdale, Ann S.; Gipson, Ilene K.

2008-01-01

Purpose Three membrane-associated mucins (MAMs)—MUC1, MUC4 and MUC16—are expressed at the ocular surface epithelium. Soluble forms of MAMs are detected in human tears, but the mechanisms of their release from the apical cells are unknown. The purpose of this study was to identify physiologic agents that induce ocular surface MAM release. Methods An immortalized human corneal-limbal epithelial cell line (HCLE) expressing the same MAMs as native tissue was used. An antibody specific to MUC16’s cytoplasmic tail was developed to confirm that only the extracellular domain is released into the tear fluid or culture media. Effects of agents that have been shown to be present in tears or are implicated in release/shedding of MAMs in other epithelia (neutrophil elastase, tumor necrosis factor (TNF), TNF-α-converting enzyme, and matrix metalloproteinases-7 and –9) were assessed on HCLE cells. HCLE cell surface proteins were biotinylated to measure efficiency of induced MAM release and surface restoration. Effects of induced release on surface barrier function were measured by rose bengal dye penetrance. Results MUC16 in tears and in HCLE-conditioned medium lacked the cytoplasmic tail. TNF induced release of MUC1, MUC4, and MUC16 from the HCLE surface. Matrix metalloproteinase-7 and neutrophil elastase induced release of MUC16 but not MUC1 or MUC4. Neutrophil elastase removed 68% of MUC16—78% of which was restored to the HCLE cell surface 24 hours after release. Neutrophil elastase-treated HCLE cells showed significantly reduced rose bengal dye exclusion. Conclusions Results suggest that extracellular domains of MUC1, 4, and 16 can be released from the ocular surface by agents present in tears. Neutrophil elastase and TNF present in higher amounts in dry eye patients’ tears may cause MAM release—allowing rose bengal staining. PMID:18436821

Commercial and Residential Water Damage: The Mold Connection.

ERIC Educational Resources Information Center

Williams, Del

2002-01-01

Describes the problem of toxic mold in residential and commercial property resulting from excess moisture. Includes common sources of unwanted moisture, design and construction flaws, determining the presence of mold, and advice for identifying and hiring reputable mold remediators. (PKP)

Molding process for imidazopyrrolone polymers

NASA Technical Reports Server (NTRS)

Johnson, C. L. (Inventor)

1973-01-01

A process is described for producing shaped articles of imidazopyrrolone polymers comprising molding imidazopyrrolone polymer molding power under pressure and at a temperature greater than 475 C. Moderate pressures may be employed. Preferably, prior to molding, a preform is prepared by isostatic compression. The preform may be molded at a relatively low initial pressure and temperature; as the temperature is increased to a value greater than 475 C., the pressure is also increased.

Apparatus for injection casting metallic nuclear energy fuel rods

DOEpatents

Seidel, Bobby R.; Tracy, Donald B.; Griffiths, Vernon

1991-01-01

Molds for making metallic nuclear fuel rods are provided which present reduced risks to the environment by reducing radioactive waste. In one embodiment, the mold is consumable with the fuel rod, and in another embodiment, part of the mold can be re-used. Several molds can be arranged together in a cascaded manner, if desired, or several long cavities can be integrated in a monolithic multiple cavity re-usable mold.

Precision injection molding of freeform optics

NASA Astrophysics Data System (ADS)

Fang, Fengzhou; Zhang, Nan; Zhang, Xiaodong

2016-08-01

Precision injection molding is the most efficient mass production technology for manufacturing plastic optics. Applications of plastic optics in field of imaging, illumination, and concentration demonstrate a variety of complex surface forms, developing from conventional plano and spherical surfaces to aspheric and freeform surfaces. It requires high optical quality with high form accuracy and lower residual stresses, which challenges both optical tool inserts machining and precision injection molding process. The present paper reviews recent progress in mold tool machining and precision injection molding, with more emphasis on precision injection molding. The challenges and future development trend are also discussed.

Using Direct Metal Deposition to Fabricate Mold Plates for an Injection Mold Machine Allowing for the Evaluation of Cost Effective Near-Sourcing Opportunities in Larger, High Volume Consumer Products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duty, Chad E; Groh, Bill

2014-10-31

ORNL collaborated with Radio Systems Corporation to investigate additive manufacturing (AM) of mold plates for plastic injection molding by direct metal deposition. The team s modelling effort identified a 100% improvement in heat transfer through use of conformal cooling lines that could be built into the mold using a revolutionary design enabled by additive manufacturing. Using the newly installed laser deposition system at the ORNL Manufacturing Demonstration Facility (MDF) a stainless steel mold core was printed.

Investigation of micro-injection molding based on longitudinal ultrasonic vibration core.

PubMed

Qiu, Zhongjun; Yang, Xue; Zheng, Hui; Gao, Shan; Fang, Fengzhou

2015-10-01

An ultrasound-assisted micro-injection molding method is proposed to improve the rheological behavior of the polymer melt radically, and a micro-injection molding system based on a longitudinal ultrasonic vibration core is developed and employed in the micro-injection molding process of Fresnel lenses. The verification experiments show that the filling mold area of the polymer melt is increased by 6.08% to 19.12%, and the symmetric deviation of the Fresnel lens is improved 15.62% on average. This method improved the filling performance and replication quality of the polymer melt in the injection molding process effectively.

Brightness field distributions of microlens arrays using micro molding.

PubMed

Cheng, Hsin-Chung; Huang, Chiung-Fang; Lin, Yi; Shen, Yung-Kang

2010-12-20

This study describes the brightness field distributions of microlens arrays fabricated by micro injection molding (μIM) and micro injection-compression molding (μICM). The process for fabricating microlens arrays used room-temperature imprint lithography, photoresist reflow, electroforming, μIM, μICM, and optical properties measurement. Analytical results indicate that the brightness field distribution of the molded microlens arrays generated by μICM is better than those made using μIM. Our results further demonstrate that mold temperature is the most important processing parameter for brightness field distribution of molded microlens arrays made by μIM or μICM.

Genomic characterization of recurrent mold infections in thoracic transplant recipients.

PubMed

Messina, Julia A; Wolfe, Cameron R; Hemmersbach-Miller, Marion; Milano, Carmelo; Todd, Jamie L; Reynolds, John; Alexander, Barbara D; Schell, Wiley A; Cuomo, Christina A; Perfect, John R

2018-05-31

Invasive mold disease in thoracic organ transplant recipients is a well-recognized complication, but the long-term persistence of molds within the human body and evasion of host defenses has not been well-described. We present 2 cases of invasive mold disease (Verruconis gallopava and Aspergillus fumigatus) in thoracic transplant recipients who had the same mold cultured years prior to the invasive disease presentation. The paired isolates from the index and recurrent infections in both patients were compared using whole-genome sequencing to determine if the same strain of mold caused both the index and recurrent infections. In Case 1, the isolates were found to be of the same strain indicating that the initial colonizing isolate identified pre-transplant eventually caused invasive mold disease post-transplant while in Case 2, the 2 isolates were not of the same strain. These results demonstrate the distinct possibility of molds both persisting within the human body for years prior to invasive mold disease or the long-term risk of recurrent, persistent infection with more than one strain. Further studies of long-term molecular epidemiology of IMD and risk factors for mold persistence in transplant recipients are encouraged. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of POE-g-MAH on properties of PP-based binder in metal injection molding

NASA Astrophysics Data System (ADS)

Li, Duxin; Zhang, Chenming; Ding, Chuxiong; Pan, Donghua; Lu, Renwei; Yang, Zhongchen

2018-06-01

The objective of this study is to explore the effects of maleic anhydride-grafted polyolefin elastomer (POE-g-MAH) on properties of polypropylene (PP)-based binder. The viscosity of feedstocks as well as properties of green parts, brown parts and sintered parts were investigated. Through the analysis of viscosity, the feedstock containing 8 vol% POE-g-MAH in binder was supposed to be more suitable for the injection molding. The impact absorbed energy at break increased with increasing POE-g-MAH content in binder while the bending strength decreased first and then increased. The introduction of POE-g-MAH improve the density distribution and increased the density of green parts. After debinding, most binder components were removed regardless of the POE-g-MAH content in binder. As for the parts after sintering, the carbon content decreased with an increase in POE-g-MAH content. The results suggest that POE-g-MAH act as a toughening agent as well as compatibilizer for PP-based binder/metal powder system. The mechanical properties of the green parts could be enhanced even after multiple injection and in addition the powder-binder separation trend could be decreased.

76 FR 16843 - Order Cancelling Registrations of Certain Transfer Agents

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-25

... SECURITIES AND EXCHANGE COMMISSION [Release No. 34-64102] Order Cancelling Registrations of Certain Transfer Agents March 21, 2011. On November 4, 2010, notice was published in the Federal Register... transfer agents.\\2\\ For the reasons discussed below, the Commission is cancelling the registration of the...

Growing Incidence of Non-Dermatophyte Onychomycosis in Tehran, Iran

PubMed Central

Motamedi, Marjan; Ghasemi, Zeinab; Shidfar, Mohammad Reza; Hosseinpour, Leila; Khodadadi, Hossein; Zomorodian, Kamiar; Mirhendi, Hossein

2016-01-01

Background Non-dermatophyte onychomycosis (NDO) is caused by a wide range of mold fungi other than dermatophytes, and has been reported at various rates in different countries worldwide. Studies on the incidence of NDO in the community are essential for understanding its epidemiology and control, as well as for the appropriate treatment of these infections. Objectives In this study, the incidence of NDO in Tehran, Iran, was compared to the incidence of onychomycoses due to dermatophytes and yeasts. Methods From 2014 through 2015, samples from a total of 1,069 patients with suspected fungal nail diseases, who were referred to three medical mycology laboratories in Tehran, were collected and subjected to direct examination (all samples) and culture (788 samples). Differentiation of the causative agents of onychomycosis was based on microscopic observation of characteristic fungal elements in the nail samples and growth of a significant number of identical colonies on the culture plate. Results Based on only direct microscopy, onychomycosis was diagnosed in 424 (39.6%) cases, among which 35.8% were caused by dermatophytes, 32.7% by yeasts, and 29.3% by non-dermatophyte molds (NDMs), while 2.2% were mixed infections. Direct exam was significantly more sensitive than culture for the diagnosis. The most commonly isolated NDMs were Aspergillus spp. (69.3%, n = 52), followed by Fusarium spp. (n = 7). The other isolated species were Paecilomyces spp., Scopulariopsis spp., Acremonium spp., Cladosporium spp., and Chrysosporium spp., with only one case of each. Conclusions An increasing frequency of NDO compared to onychomycosis due to other causative agents has been noticeable over the past few years in Iran. This epidemiological data may be useful in the development of preventive and educational strategies. PMID:27800138

[Preparation of ondansetron hydrochloride osmotic pump tablets and their in vitro drug release].

PubMed

Zheng, Hang-sheng; Bi, Dian-zhou

2005-12-01

To prepare ondansetron hydrochloride osmotic pump tablets (OND-OPT) and investigate their in vitro drug release behavior. OND-OPT were prepared with a single punch press and pan coating technique. Osmotic active agents and plasticizer of coating film were chosen by drug release tests. The effects of the number, position and direction of drug release orifice on release behavior were investigated. The relation between drug release duration and thickness of coating film, PEG content of coating film and size of drug release orifice was established by uniform design experiment. The surface morphological change of coating film before and after drug release test was observed by scanning electron microscopy. The osmotic pumping release mechanism of OND-OPT was confirmed by drug release test with high osmotic pressure medium. Lactose-mannitol (1:2) was chosen as osmotic active agents and PEG400 as plasticizer of coating film. The direction of drug release orifice had great effect on the drug release of OND-OPT without HPMC, and had no effect on the drug release of OND-OPT with HPMC. The OND-OPT with one drug release orifice at the centre of the coating film on one surface of tablet released their drug with little fluctuation. The drug release duration of OND-OPT correlated with thickness of coating film and PEG content of coating film, and didn't correlate significantly with the size of drug release orifice. OND-OPT released their drug with osmotic pumping mechanism predominantly. OND-OPT are able to realize ideal controlled drug release.

Miniature Inchworm Actuators Fabricated by Use of LIGA

NASA Technical Reports Server (NTRS)

Yang, Eui-Hyeok

2003-01-01

Miniature inchworm actuators that would have relatively simple designs have been proposed for applications in which there are requirements for displacements of the order of microns or tens of microns and for the ability to hold their positions when electric power is not applied. The proposed actuators would be members of the class of microelectromechanical systems (MEMS), but would be designed and fabricated following an approach that is somewhat unusual for MEMS. Like other MEMS actuators, the proposed inchworm actuators could utilize thermoplastic, bimetallic, shape-memory-alloy, or piezoelectric actuation principles. The figure depicts a piezoelectric inchworm actuator according to the proposal. As in other inchworm actuators, linear motion of an extensible member would be achieved by lengthening and shortening the extensible member in synchronism with alternately clamping and releasing one and then the other end of the member. In this case, the moving member would be the middle one; the member would be piezoelectric and would be shortened by applying a voltage to it. The two outer members would also be piezoelectric; the release of the clamps on the upper or lower end would be achieved by applying a voltage to the electrodes on the upper or lower ends, respectively, of these members. Usually, MEMS actuators cannot be fabricated directly on the side walls of silicon wafers, yet the geometry of this actuator necessitates such fabrication. The solution, according to the proposal, would be to use the microfabrication technique known by the German acronym LIGA - "lithographie, galvanoformung, abformung," which means lithography, electroforming, molding. LIGA involves x-ray lithography of a polymer film followed by selective removal of material to form a three-dimensional pattern from which a mold is made. Among the advantages of LIGA for this purpose are that it is applicable to a broad range of materials, can be used to implement a variety of designs, including those of structures >1 mm high, affords submicron precision, and is amenable to mass production at relatively low unit cost. Fabrication of the proposed actuators would involve some technological risks - in particular, in the integration of electrode connection lines and placement of actuator elements. It will also be necessary to perform an intensive study of the feasibility of growing piezoelectric crystals onto LIGA molds.

Relative potency estimates of acceptable residues and reentry intervals after nerve agent release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Watson, A.P.; Jones, T.D.; Adams, J.D.

1992-06-01

In the event of an unplanned release of a chemical warfare agent during any stage of the Chemical Stockpile Disposal Program, the potential exists for off-post contamination of drinking water, forage crops, grains, garden produce, and livestock. The more persistent agents, such as the organophosphate nerve agent VX, pose the greatest human health concern for reentry. A relative potency approach comparing the toxicity of VX to organophosphate insecticide analogues is developed and used to estimate allowable residues for VX in agricultural products and reentry intervals for public access to contaminated areas. Analysis of mammalian LD50 data by all exposure routesmore » indicates that VX is 10(3) to 10(4) times more toxic than most commercially available organophosphate insecticides. Thus, allowable residues of VX could be considered at concentration levels 10(3) to 10(4) lower than those established for certain insecticides by the U.S. EPA. Evaluation of reentry intervals developed for these organophosphate analogues indicate that, if environmental monitoring cannot reliably demonstrate acceptable levels of VX, restricted access to suspect or contaminated areas may be on the order of weeks to months following agent release. Planning for relocation, mass care centers, and quarantine should take this time period into account.« less

Multiphysics modeling of the steel continuous casting process

NASA Astrophysics Data System (ADS)

Hibbeler, Lance C.

This work develops a macroscale, multiphysics model of the continuous casting of steel. The complete model accounts for the turbulent flow and nonuniform distribution of superheat in the molten steel, the elastic-viscoplastic thermal shrinkage of the solidifying shell, the heat transfer through the shell-mold interface with variable gap size, and the thermal distortion of the mold. These models are coupled together with carefully constructed boundary conditions with the aid of reduced-order models into a single tool to investigate behavior in the mold region, for practical applications such as predicting ideal tapers for a beam-blank mold. The thermal and mechanical behaviors of the mold are explored as part of the overall modeling effort, for funnel molds and for beam-blank molds. These models include high geometric detail and reveal temperature variations on the mold-shell interface that may be responsible for cracks in the shell. Specifically, the funnel mold has a column of mold bolts in the middle of the inside-curve region of the funnel that disturbs the uniformity of the hot face temperatures, which combined with the bending effect of the mold on the shell, can lead to longitudinal facial cracks. The shoulder region of the beam-blank mold shows a local hot spot that can be reduced with additional cooling in this region. The distorted shape of the funnel mold narrow face is validated with recent inclinometer measurements from an operating caster. The calculated hot face temperatures and distorted shapes of the mold are transferred into the multiphysics model of the solidifying shell. The boundary conditions for the first iteration of the multiphysics model come from reduced-order models of the process; one such model is derived in this work for mold heat transfer. The reduced-order model relies on the physics of the solution to the one-dimensional heat-conduction equation to maintain the relationships between inputs and outputs of the model. The geometric parameters in the model are calibrated such that the reduced-order model temperatures match a small, periodic subdomain of the mold. These parameters are demonstrated to be insensitive to the calibration conditions. The thermal behavior of the detailed, three-dimensional mold models used in this work can be approximated closely with a few arithmetic calculations after calibrating the reduced-order model of mold heat transfer. The example application of the model includes the effects of the molten steel jet on the solidification front and the ferrostatic pressure. The model is demonstrated to match measurements of mold heat removal and the thickness of a breakout shell all the way around the perimeter of the mold, and gives insight to the cause of breakouts in a beam-blank caster. This multiphysics modeling approach redefines the state of the art of process modeling for continuous casting, and can be~used in future work to explore the formation and prevention of defects and other practical issues. This work also explores the eigen-problem for an arbitrary 3x3 matrix. An explicit, algebraic formula for the eigenvectors is presented.