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Liquid metal (LM) plasma-facing components (PFCs) may provide a resolution to the challenging fusion environment, particularly the first wall and divertor surfaces. Transforming these concepts into viable technologies will require considerable research and development. With the fusion nuclear regime in mind, the Fusion Energy System Studies group examined LM PFCs in order to identify needed research thrusts that could accelerate their development and assess their viability. Liquid metal behavior, solid substrate aspects, and fusion facility integration aspects are examined, with concepts as the research focusing element. The concepts applied to a fusion nuclear device are the primary definer of the LM parameters, environmental conditions, and operational aspects. This forms the research strategy recommended for these complex systems. [ABSTRACT FROM AUTHOR]

The article discusses a plan for monitoring how soil and water conservation practices are being maintained. Topics covered include the aspects of the social monitoring plan, a step-by-step guide in the development of the plan, a detailed explanation of each step and a list of questions that may provide key information. Also presented are tables and templates that can be used in the monitoring plan.

A metabolism study of orally administered 2,2',4,4',5,6'-hexabromodiphenyl ether (BDE-154; 11.3 μmoles kg-1) was conducted in conventional and bile duct-cannulated male Sprague-Dawley rats. In conventional rats, approximately 31% of the radiolabelled dose was retained at 72 h, and lipophilic tissues were the preferred sites for disposition. Urinary excretion of BDE-154 was very low (1.0%), and parent compound was detected. Cumulative biliary excretion was 1.3%, and glutathione conjugates were suggested. Over 62% of the dose in conventional male rats was excreted in faeces, and was composed of parent compound (7.3%), free metabolites (13.1%), and covalently bound residues (41.4%). Faecal metabolites characterized by gas chromatography/mass spectrometry included multiple isomers of monohydroxylated hexa-/penta-/tetrabromodiphenyl ethers, and di-hydroxylated hexa/pentabromodiphenyl ethers. The adipose tissue 14C was extractable BDE-154, but 40% of liver 14C was bound to macromolecules. The study demonstrated the importance of performing individual polybrominated diphenyl ether (PBDE) metabolism studies to understand fully PBDE pharmacokinetics. [ABSTRACT FROM AUTHOR]

The absorption, disposition, metabolism and excretion study of orally administered 2,2',4,4',6-pentabromodiphenyl ether (BDE-100) was studied in conventional and bile-duct cannulated male rats. In conventional rats, >70% of the radiolabelled oral dose was retained at 72?h, and lipophilic tissues were the preferred sites for disposition, i.e. adipose tissue, gastrointestinal tract, skin, liver and lungs. Urinary excretion of BDE-100 was very low (0.1% of the dose). Biliary excretion of BDE-100 was slightly greater than that observed in urine, i.e. 1.7% at 72?h, and glucuronidation of phenolic metabolites was suggested. Thiol metabolites were not observed in the bile as had been reported in other PBDE metabolism studies. Almost 20% of the dose in conventional male rats and over 26% in bile-duct cannulated rats was excreted in the faeces, mainly as the unmetabolized parent, although large amounts of non-extractable radiolabel were also observed. Extractable metabolites in faeces were characterized by mass spectrometry. Monohydroxylated pentabromodiphenyl ether metabolites were detected; mono- and di-hydroxylated metabolites with accompanying oxidative debromination were also observed as faecal metabolites. Tissue residues of [ 14 C]BDE-100 in liver, gastrointestinal tract and adipose tissue contained only parent material. The majority of the 0–72-h biliary radioactivity was associated with an unidentified 79-kDa protein or to albumin. [ABSTRACT FROM AUTHOR]

Adipose tissue samples from 158 cattle raised locally at experiment stations across the USA were analysed for polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/F). While 80% of the samples had PCDD/F concentrations that fell within the range of a previous US survey of beef animals (not detected -4.1 ppt toxic equivalency), several animals had exceptionally high concentrations (8-54 ppt toxic equivalency). The investigations of three facilities where highly contaminated animals were raised found pentachlorophenol-treated wood at each site. The congener pattern in the animals' tissues and the lack of elevated PCDD/F levels in other environmental samples, i.e. hay and soil, indicated that the treated wood was the source of contamination. A congener pattern similar to that of pentachlorophenol-exposed animals was seen for the means and medians of the entire data, i.e. OCDD, HpCDD and 1,2,3,6,7,8-HxCDD dominated, the PCDD concentrations equalled or exceeded the furan concentrations, and the concentration of 1,2,3,6,7,8-HxCDD was six times that of the other HxCDD isomers. This suggested that pentachlorophenol-treated wood contributed measurably to many of the animals in this survey. The largest contributors to the median toxic equivalencies were 1,2,3,7,8-PeCDD (40%) and 1,2,3,6,7,8-HxCDD (16%). No clear geographical trends emerged from the data. [ABSTRACT FROM AUTHOR]

1. Two [[sup 14]C]-labelled brominated diphenyl ethers, 2,2′,4,4′,5-pentabromodiphenyl ether (BDE-99) and decabromodiphenyl ether (BDE-209), were separately administered to the male Sprague-Dawley rat as a single oral dose (2.2mgkg[sup -1] body weight and 3.0mgkg[sup -1], respectively). 2. Very low [[sup 14]C] urine excretion was observed for both congeners (<1% of the dose), and cumulative biliary excretion was approximately 4% for BDE-99 and 9% for BDE-209. 3. More than 6% of the pooled urine from the BDE-99-treated rat was protein-bound to an 18-kDa protein characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western immunoblot analysis as α[sub 2u]-globulin. Eighteen per cent of the radioactivity from the pooled urine from the BDE-209 treated rat was bound to albumin; no binding to α2u-globulin was detected. 4. In bile, 27-39% of the radioactivity from the BDE-99-dosed rat was bound to an unidentified 79-kDa protein, whereas essentially all (>87%) of the biliary radioactivity from BDE-209 was bound to the 79-kDa protein. Both parent BDE-99 and-209 and their metabolites were detected by thin layer chromatography in the extracted fraction of this bile protein. 5. By differential centrifugation, the subcellular localization of the [sup 14]C derived from each congener in selected tissues was quantified. The cytosolic [[sup 14]C] from livers of the BDE-209-treated rat was bound to a 14-kDa protein, which was characterized as a fatty acid-binding protein. [ABSTRACT FROM AUTHOR]

1. After an oral dose of [sup 14]C-labelled 3,3′,4,4′-tetrachlorobiphenyl (CB-77), the conventional germ-free and bile-duct cannulated male Sprague-Dawley rat excreted approximately 80% of the dose in faeces and/or bile within 3 days. 2. For the germ-free and conventional rat, 15% of the dose was excreted via the faeces as metabolites covalently bound to lipids. Bile-duct-cannulated rats excreted similar amounts of lipid-bound metabolites in the bile. The lipid-bound metabolites appear to be formed in the liver and excreted via the bile, and the microflora did not seem essential for the formation of lipid-bound metabolites. 3. The novel CB-77 metabolites had chemical and physical properties similar to those of lipids with regard to solubility and polarity, as determined by partition characteristics on various chromatographic systems. 4. In addition to identification of hydroxylated CB-77 metabolites, several fatty acid esters of hydroxy-chlorobiphenyls were indicated and one hydroxy-tetrachlorobiphenylol palmitoate was identified, but fatty acid esters were minor metabolites. 5. Approximately 70% of the lipid-bound metabolites were present in the fraction that contained phospholipids. The formation of lipid-bound CB-77 metabolites seems a spontaneous reaction rather than an enzymatically catalysed reaction, as indicated by the large number of different lipid-bound metabolites. [ABSTRACT FROM AUTHOR]

1. A disposition, metabolism and excretion study of orally administered 2,2′,4,4′,5-pentabromodiphenyl ether (BDE-99) was conducted in the conventional and bile duct-cannulated male rat. 2. In the conventional rat, >50% of the radiolabelled dose was retained at 72 h, and lipophilic tissues were the preferred sites for disposition, i.e. adipose tissue, adrenals, gastrointestinal tract and skin. 3. Urinary excretion of BDE-99 was very low (<1% of dose), and glucuronidation of phenolic metabolites was suggested. 4. Biliary excretion of BDE-99 was slightly greater than observed in urine, i.e. 3.6% at 72h. 5. Over 43% of the dose in the conventional male rat and 86% in the bile duct-cannulated rat was excreted in the faeces, mainly as the unmetabolized parent compound. 6. Metabolites in bile and faeces were not conjugated. Mono- and di-hydroxylated pentabromodiphenyl ether metabolites were characterized by mass spectrometry. Two thiol metabolites were characterized in the bile. Oxidative debromination was also observed in the faecal metabolites. 7. Tissue BDE-99 was readily extractable, except for in the liver. The tissue [sup 14]C was not associated with lipids and was mainly the unmetabolized parent compound. 8. Total thyroxine (T4) plasma levels were elevated at 3 and 6 days, and returned to control levels by day 12. [ABSTRACT FROM AUTHOR]

1. [UL-7,8-ring [sup 14]C]-1,2,7,8-tetrachlorodibenzo-p-dioxin (1278-TCDD) was administered orally to a ruminating Holstein bull calf (43.6 kg; 1.2 mg kg[sup -1] body weight). Urine and faeces were collected daily for 96 h, while blood was sampled at multiple time points. Tissues were removed for combustion analysis. 2. Each tissue contained < 0.6% of the dose at 96h. Tissues with highest levels of 1278-TCDD, as a percentage of administered dose, were the large and small intestine, rumen, liver and carcass. 3. Urinary excretion accounted for 10.6% of the dose, and faecal excretion accounted for 81.6% of the administered dose. The major urinary and faecal metabolites were isolated and characterized by mass spectrometry and [sup 1]H-NMR. 4. Plasma levels of [sup 14]C peaked at 24 h, and decreased to near background at 96 h. Detectable plasma levels of 1278-TCDD were observed by 2 h. 5. A hydroxylated metabolite of 1278-TCDD was detected in calf plasma, which has the potential to interfere with thyroid hormone homeostasis. [ABSTRACT FROM AUTHOR]

1. Radioactivity from oral doses of N-isopropyl[1-[sup 14]C]acetanilide was excreted in urine (53.5%), faeces (8.1%) and expired air (17.0%) of rat. 2. Enterohepatic circulation occurred during formation of 34% of the metabolites. N-isopropylacetanilide was metabolized by oxidation in all moieties of the molecule with subsequent conjugation with glucuronic and sulphuric acids. 3. The sulphate ester of 4'-hydroxyacetanilide (acetaminophen) was the major metabolite (28% of the dose). [ABSTRACT FROM AUTHOR]

1. [sup 14]C-TBBP-A (2,2-bis(4-hydroxy-3,5-dibromophenyl)propane) was administered orally to the conventional and bile-duct cannulated male Sprague-Dawley rat (2.0 mg/kg body weight). Urine, bile and faeces were collected daily for 72 h, and selected tissues were removed for distribution studies. 2. Faeces was the major route of elimination of TBBP-A in the conventional rat (9.7% of dose), and urine was a minor elimination route (0.3%). Enterohepatic circulation was suggested by biliary excretion of 71.3% and faecal excretion of 26.7% of the administered radioactivity in the bile-duct cannulated rat. 3. [sup 14]C-labelled residues in tissues were 2% in the conventional rat, and <1% in the bile-duct cannulated rat. The large and small intestines contained the majority of the tissue [sup 14]C activity for both groups of rat. Levels of TBBP-A in liver were < 0.1%, and in fat were below the level of quantification. 4. Three metabolites were characterized in 0-24 h bile samples. Glucuronic acid and sulphate ester conjugates were characterized by mass spectrometry. More than 95% of the extractable faecal [sup 14]C was identified as parent TBBP-A. 5. Negligible amounts of TBBP-A-derived [sup 14]C were associated with carrier proteins he urine and bile. [ABSTRACT FROM AUTHOR]

An adaptive equalization method for high-speed and/or long-haul baseband data transmission is described which uses the pulse length as a control criterion. The method does riot depend on the attenuation of the signal and can be applied to all types of switched cables as well as overhead lines. [ABSTRACT FROM AUTHOR]

A suitable Automatic Gain Control (AGC) in baseband data communication receivers is essential for a low error rate of the link. Analogue AGC suffers from conflicting demands of time constants. This paper describes a receiver using digitally controlled AGC overcoming these difficulties. [ABSTRACT FROM AUTHOR]

1. Nearly 70% of single oral doses of C-labelled pentachloronitrobenzene (PCNB) was excreted in bile within 24 h. 2. The characterized biliary metabolites of PCNB were either mercapturic acid pathway metabolites or catabolites thereof (thiols, methylthiols, S-glucuronides). 3. A major biliary metabolite was S -(aminotetrachlorophenyl)glutathione. 4. Conjugation with glutathione with subsequent catabolism to bis-methylthiotetrachlorobenzene was the major pathway in the control rat. 5. Germ-free experiments showed that only nitro- group displacement occurred, and no nitro-group reduction was detected. [ABSTRACT FROM AUTHOR]