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Percutaneous transluminal coronary angioplasty (PTCA) is a procedure for treating diseased coronary arteries that are narrowed or blocked, usually by fatty atherosclerotic plaques. PTCA involves inserting a balloon-tipped catheter into the constricted region and inflating the balloon to widen the diameter of the artery. The procedure can be dangerous, particularly in patients with heart problems affecting the left ventricle, which pumps blood from the heart to the body. PTCA can cause temporary blockages in coronary vessels and result in ischemia, or diminished blood flow to the heart, aggravating preexisting conditions. This study examined the use of hemoperfusion during PTCA; this technique involves injecting blood into the heart during PTCA to prevent ischemia. Measurements of left ventricular function and ischemia were recorded in nine patients who underwent PTCA, with and without hemoperfusion. The patients were men and had an average age of 52 years. Chest pain was reported in three patients during PTCA when hemoperfusion was not used, and in one when it was used. Left ventricular (LV) systolic pressure (during contraction) was significantly decreased during PTCA without hemoperfusion, but remained stable with it. LV end-diastolic pressure (when the ventricle fills with blood) increased to a much greater extent without hemoperfusion than with it. Other measures of LV function were better when hemoperfusion was used during PTCA than when it was not. These results indicate that hemoperfusion can be effective in protecting the heart from ischemia during PTCA, especially in high-risk patients. (Consumer Summary produced by Reliance Medical Information, Inc.)

Reviewed by Kenneth W. Watson, assistant director of the Chicago Child Care Society, Chicago, Illinois. This stimulating, well-written book invites both quotation and response. The authors' central premise is that [...]

The article focuses on establishing the near- and long-term materiel readiness of the Afghan National Army that requires urgent attention to inherent challenges and a system-of-systems approach. Topics include problems such as oversized, aging fleets, current state of materiel readiness in the Afghan National Army (ANA) as dire with regard to vehicle fleets and weapon serviceability, comparison of the U.S. Army standard for the appropriate ratio of wheeled vehicle mechanics to vehicle systems.

Prior investigations of scotopic sensitivity or Meares-Irlen syndrome have identified several features also found in attention deficit/hyperactivity disorder, chronic fatigue syndrome, and a subtype of dyslexia in which visual recognition is the primary deficit. In particular, anomalies in lipid metabolism, including low essential fatty acid status and decreased serum cholesterol, have been identified in all three disorders. Genetic expression of the transporter molecule apolipoprotein B-100 (APOB) has been correlated with abnormal lipid metabolism, particularly in relation to levels of cholesterol. Cholesterol esters are important carriers of essential fatty acids entering the retina. The APOB gene coding for apolipoprotein B-100 is located on the short arm of Chromosome 2, and closely neighbours a gene (DYX3) known to confer susceptibility to dyslexia. The APOB locus is also recognised as being one of the most highly polymorphic regions of the human genome, and thus provides a promising tool for genetic researchers. In this pilot study, certain allelic variants of the APOB gene were more common in participants diagnosed with Meares–Irlen syndrome than in individuals without the condition. This study appears to be a first in which a condition known to cause reading difficulties has been associated with the APOB gene.

INTRODUCTION: The objective of this laboratory study was to measure the effect of decreased lung compliance and endotracheal tube (ETT) leakage on measured exhaled tidal volume at the airway and at the ventilator, in a research study with a test lung. METHODS: The subjects were infant, adult and pediatric test lungs. In the test lung model, lung compliances were set to normal and to levels seen in acute respiratory distress syndrome. Set tidal volume was 6 ml/kg across a range of simulated weights and ETT sizes. Data were recorded from both the ventilator light-emitting diode display and the CO2SMO Plus monitor display by a single observer. Effective tidal volume was calculated from a standard equation. RESULTS: In all test lung models, exhaled tidal volume measured at the airway decreased markedly with decreasing lung compliance, but measurement at the ventilator showed minimal change. In the absence of a simulated ETT leak, calculation of the effective tidal volume led to measurements very similar to exhaled tidal volume measured at the ETT. With a simulated ETT tube leak, the effective tidal volume markedly overestimated tidal volume measured at the airway. CONCLUSION: Previous investigators have emphasized the need to measure tidal volume at the ETT for all children. When ETT leakage is minimal, it seems from our simulated lung models that calculation of effective tidal volume would give similar readings to tidal volume measured at the airway, even in small patients. Future studies of tidal volume measurement accuracy in mechanically ventilated children should control for the degree of ETT leakage.

Summary: Methyl 2-cyano-3-dihalophenyl-2-propenoates, R2C6H3CH=C(CN)CO2CH3 (R2= 2,4-difluoro, 2,5-difluoro, 2,6-difluoro, 3,4-difluoro, 3,5-difluoro, and 2-chloro-6-fluoro), were prepared by the piperidine catalyzed Knoevenagel condensation of corresponding disubstituted benzaldehydes and methyl cyanoacetate. Novel copolymers of the propenoates and styrene were prepared at equimolar monomer feed by solution copolymerization in the presence of a radical initiator. The order of relative reactivity (1/r 1) was 2,5-difluoro (2.11) > 2,6-difluoro (1.84) > 3,5-difluoro (1.71) > 2,4-difluoro (1.4) > 3,4-difluoro (0.65) > 2-chloro-6-fluoro (0.59). The copolymers were characterized by IR, 1H and 13C NMR, GPC, DSC and TGA. High glass transition temperatures of the copolymers compared that of polystyrene indicates a substantial decrease in chain mobility of the copolymers due to the high dipolar character of the trisubstituted ethylene monomer unit.

Electrophilic trisubstituted ethylenes, ring-disubstituted methyl 2-cyano-3-phenyl-2-propenoates, RCH=C(CN)CO2CH3(where R = 2,3-dichlorophenyl, 2,4-dichlorophenyl, 2,6-dichlorophenyl, 3,4-dichlorophenyl, 4-chloro-3-nitrophenyl, 5-chloro-2-nitrophenyl, 2-chloro-6-fluoro), were prepared and characterized. All the propenoates, except methyl 2-cyano-3-(4-chloro-3-nitrophenyl)-2-propenoate, were copolymerized with styrene (M1) in solution with radical initiation (AIBN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H-, and 13C-NMR. The order of relative reactivity (1/r1) for the monomers is 2,4-dichloro (2.1) = 3,4-dichloro (2.1) > 2,6-dichloro (0.8) = 2,3-dichloro (0.8) > 2-chloro-6-fluoro (0.6) > 5-chloro-2-nitro (0.2). The high glass transition temperatures of the copolymers (> 190°C) in comparison with that of polystyrene indicate a substantial decrease in the chain mobility of the copolymers due to the high dipolar character of the trisubstituted monomer unit. Gravimetric analysis indicated that the copolymers decompose in the range 300-400°C.

In Part 1 of this work we presented a new mathematical formulation for numerical investigation of capillary wave dynamics. This permitted calculations to be readily performed on a desktop computer. Applications given were primarily to waves in one surface dimension. In Part 2 we describe further applications to waves in two surface dimensions and also to waves in shallow water (not, however, shallow for the capillary waves). Wavenumber–frequency spectra for wind waves are calculated. As was observed in tank experiments by Hara et al. (1997), our calculations show both a frequency spread and a frequency up-shifting which suggests that capillary waves are ‘dragged along’ by longer waves. Fine-scale roughness near wind wave crests shows a transitory nature, changing with the wave pattern. We discuss implications of this for microwave remote sensing. The propagation of short gravity waves in shallow water is studied. As these waves develop bore-like forward faces, generation of parasitic capillary waves is observed. Generation rates for these are substantially greater than observed for waves in deep water.

The role of ergosterol in yeast stress tolerance, together with heat shock proteins (hsps) and trehalose, was examined in a sterol auxotrophic mutant of Saccharomyces cerevisiae. Ergosterol levels paralleled viability data, with cells containing higher levels of the sterol exhibiting greater tolerances to heat and ethanol. Although the mutant synthesised hsps and accumulated trehalose upon heat shock to the same levels as the wild‐type cells, these parameters did not relate to stress tolerance. These results indicate that the role of ergosterol in stress tolerance is independent of hsps or trehalose.

During processing of vegetable oils, certain by-products and waste materials are generated. Where and how the by-products are recovered and used and how the solid wastes are handled and disposed of are considered. Several suggestions for the future are explored.

Heat shock (25°C to 37°C for 30 min) acquisition of thennotolerance (at 50°C) was observed in a yeast trehalose synthase mutant and the corresponding control strain. The acquisition of thermotolerance in the control strain was maintained for a significantly longer time in the trehalose synthase mutant. The heat shock was associated with the synthesis of specific heat shock proteins and, in the case of the control strain, also trehalose accumulation. Inhibition of protein synthesis during the heat shock totally abolished acquisition of thermotolerance in both strains but not trehalose accumulation in the control. It was concluded that trehalose may only be required for prolonged stress protection while heat shock proteins are required for heat shock acquisition of thermotolerance.

The experiments reported here show that heat shock treatment of a number of different strains ofSaccharomycesresults in a marked increase in ethanol tolerance as compared to control cells. Our observations thus imply a relationship between the synthesis of heat shock proteins and the acquisition of ethanol tolerance in yeast.

Heat shock acquisition of ethanol- and thermotolerance in Saccharomyces cerevisiaewas not inhibited in cells incubated in the presence of cycloheximide or chloramphenicol. Respiratory-deficient (ρ −) mutants also characteristically exhibited the heat shock response. It was concluded that mitochondrial and cytoplasmic protein syntheses are not required for heat shock acquisition of ethanol and thermotolerance in yeast.

A system of waves coupled by three-wave, or triad, interactions is considered. A model is constructed to describe the response of a single test wave to interaction with a “heat bath” of “ambient waves.” An exact solution for the relaxation of the test wave amplitude is obtained. Regimes of validity are shown for the use of a Langevin equation based on a two-time scale perturbation theory.

Yeast cells when subjected to a primary heat shock, defined as a temperature shift from 23 to 37° for 30 min, acquired tolerance to heat stress (52°C/5 min). Primary heat shocked cells incubated at 23°C for up to 3 h, progressively lost thermotolerance but retained high levels of the major heat‐shock proteins as observed on polyacrylamide gels. On the other hand, a temperature shift back up to 37°C for 30 min fully restored thermotolerance. The major high‐molecular‐mass heat‐shock proteins (hsp) identified were of approximate molecular mass 100 kDa (hsp 100), 80 kDa (hsp 80) and 70 kDa (hsp 70). The results indicate that loss of heat‐shock acquisition of thermotolerance is not correlated with loss of heat‐shock proteins.

Conditions are described for the heat shock acquisition of thermotolerance, peroxide tolerance and synthesis of heat shock proteins (hsps) in the Antarctic, psychrophilic yeast Candida psychrophila.Cells grown at 15°C and heat shocked at 25°C (3 h) acquired tolerance to heat (35°C) and hydrogen peroxide (100 mM). Novel heat shock inducible proteins at 80 and 110 kDa were observed as well as the presence of hsp 90, 70 and 60. The latter hsps were not significantly heat shock inducible. The absence of hsp 104 was intriguing and it was speculated that the 110 kDa protein may play a role in stress tolerance in psychrophilic yeasts, similar to that of hsp 104 in mesophilic species.

The azines of acetophenone and its mono- and di-chlorinated derivatives show a bathochronic shift in the yellow region, but the azine of trichloroacetophenone is colorless. Similar trends are observed in the brominated analogs and in the chlorinated propiophenone azines. The colorless tétrachloropropiophénone azine (13) is shown by X-ray analysis to be nonplanar at the azine atoms (N—N torsion angle, 126.7°). Hexachloroacetophenone azine (9) undergoes displacement of all its chlorines with NaOMe to give the hexamethoxy compound 16, also colorless. With acid, 16gives the yellow planar (X-ray) ketazine diester 20. These reactions appear to be general for the trichloromethyl group in azines, but not for the α,α-dichloroalkyl group, attempts at the sequence 13to 28proving unsuccessful.

Summary Amino acid analyses were undertaken on single cell protein (SCP) produced by thermotolerant strains ofKluyveromyces marxianus var.marxianus grown on sugar cane molasses at 40°C. The maximum conversion of available sugars to biomass at 45°C was only 10.8% (g dry wt.·g-1 total sugars). The amino acid composition of the SCP did not differ markedly from that reported for other yeast species.

Reduced streptolysin O, a toxin produced by certain β-haemolytic streptococci, lyses human erythrocytes. The reaction is inhibited by cholesterol at concentrations of about 1.0μg/ml. Other sterols inhibit the lysin and there is a specific requirement for a 3β-hydroxyl group. Inhibition was obtained with 3β-hydroxychol-5-en-24-oic acid, containing a hydrophilic group at C-24. The mode of inhibition is likely to involve attachment to the fixation site of the lysin which attaches the molecule to cell membranes, probably to membrane cholesterol. A second streptolysin site, concerned in the final haemolytic event, may also be involved. Inhibitors of the latter site have not been characterized, other than antibody with specificity for the site.

A family-centered approach for providing adoption services is described. The impact of adoption on ordinary life issues (family boundaries and membership, loss, self-esteem, autonomy, and identity) is discussed from a family-centered perspective, and successful intervention techniques with persons involved in adoptions are presented.

The membrane lipid composition of Saccharomyceswas manipulated by growing cells anaerobically with or without ergosterol and unsaturated fatty acid. Cells low in ergosterol but enriched in unsaturated fatty acid residues on membrane phospholipids produced high concentrations, 13–15.5% w/v, of ethanol at substrate conversion efficiencies of around 90%.

Fumarate-based polyesters were prepared by the transesterification polycondensation of diethyl fumarate and diols: (±)-1,2-propanediol, (S)-(+)-1,2-propanediol, 2-methyl-1,3-propanediol, and 2,2-dimethyl-1,3-propanediol. Different polyester microstructures were observed by ¹H-NMR and ¹³C-NMR spectroscopy when the reaction was conducted in the presence of p-toluenesulfonic acid monohydrate or metal containing catalysts—aluminum trichloride, titanium tetrachloride, titanium tetrabutoxide, and zinc chloride. The extent of formation of branched structures associated with hydroxyl end groups' addition to the unsaturated polyester double bonds depends on the acidity of the catalyst. The bone cement composites were prepared by mixing the fumarate polyesters with an inorganic filler, CaSO4 · 2H2O, and N-vinyl pyrrolidone, which crosslinks on the addition of a radical initiator, benzoyl peroxide, at ambient temperatures. The compressive strength and hydrolytic stability of the cement compositions was correlated with structure of the polyesters. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1123–1137, 1997

We have described the use of differential display of PCR‐amplified reverse transcribed mRNA (DDRT‐PCR) to survey changes in gene expression profiles induced by heat shock and carbon catabolite derepression in Saccharomyces cerevisiae. It is well established that either of these states elicits thermotolerant phenotypes. An initial analysis conducted on cells of an inherently thermosensitive strain (Ysen) indicated that approximately 10% of the total number of cDNAs detected were either up or down regulated following heat shock at 37°C (30 min) in comparison to control cells (25°C). In addition, whereas 7% of all PCR products were preferentially expressed during derepressive growth, approximately 2% were found to be common to both heat‐shocked and derepressed cells. A repeat analysis, performed on all three cell types of Ysen as well as cells of a relatively thermoresistant strain (Yres) yielded 30 differentially displayed cDNA fragments common to heat‐shocked and derepressed cells of both strains. Eighteen of these generated signals on Northern blots, of which three were confirmed as regulated. Five amplicons, including one not detected by Northern analysis and another from the derepressed state, were cloned and sequenced. Three of these exhibited homology to S. cerevisiaegenes with well‐characterized protein products: HSP 90, HXK1and STA1. The remaining two applicons showed nucleotide identity to YTIS11, a homolog of the mammalian TIS11and putative transcriptional activator, and an orphan gene encoding a hypothetical transmembrane protein belonging to the multi‐drug resistance translocase family. Our novel application of DDRT‐PCR has identified new and known genes that may be further evaluated as factors involved in stress regulation and has demonstrated the potential of the technique to systematically analyse gene expression in yeast. © 1998 John Wiley & Sons, Ltd.

The nitrosocarbonyl arenes or -alkanes, obtained by oxidation of hydroxamic acids, behave as dienophiles towards cyclopentadiene to give the bridged oxazines 1. In the case of pivalo-hydroxamic acid, however, the nitrosocarbonyl compound also reacts as a heterodiene, giving, as well as the oxazine 1d, the 1,4,2-dioxazine 2d; 1dis not converted into 2dunder the conditions of the oxidation reaction.Extended heating of compounds 1slowly converts them into 2and other more complex reaction products. This contrasts with the rapid and quantitative isomerization of the analogous azodicarbonyl adducts, and probably reflects the lesser crowding of the reacting NCOR group by an adjacent oxygen than by an adjacent NCOR group.1,4-Dimethyl-2,3-diphenylcyclopentadiene traps the nitroso compounds to form the labile oxazines 8, which rapidly isomerize to the dioxazines 9on brief heating or in polar solvents. In the case of the benzoyl compound 8athe isomerization to 9ais reversible in benzene at 80 °C, favouring the latter isomer by a factor of about 9:1.

We consider the propagation of weakly nonlinear waves such as plasma waves, surface water waves, the interaction of laser beams with matter, particle accelerators, etc. Specifically, we study internal waves in the ocean. Hamilton's principle is used to write the fluid equations in Hamiltonian form in terms of linear eigenmode amplitudes. Numerical studies are made of the effect of Fourier grid size and resonance widths. Statistical information is generated from an ensemble of initial states of the random wave field.

Abstract: Phenomena associated with weakly nonlinear waves are encountered in optics, plasma physics, and geophysics. Specific applications in oceanography include ocean surface waves, internal gravity waves, Rossby waves, and interactions between these wave systems. Techniques for studying these phenomena include direct numerical integration, Boltzmann-like transport equations, and Langevin transient response functions. A simple model, called thetest wave model, is described and used to illustrate comparison of these methods.

Copolymerization of methyl 2-cyano-3-phenyl-2-propenoate (MCP) and 2-phenyl-1,1-dicyanoethene (PDE) with ethyl, n-butyl, i-butyl, 2-chloroethyl, and phenyl vinyl ethers in broad ranges of comonomer ratios always produces copolymers of an equimolar composition. The alternating structure of these copolymers was established by elemental analysis and by infrared, 1H- and 13C-NMR spectroscopy. Microstructure analysis of the copolymer of PDE and phenyl vinyl ether, as deduced from 1H and NOESY 13C-NMR data, demonstrated the formation of alternating monomer structures with different orientations of the monomer units. Additional characterization of the copolymers was carried out by DSC and TGA. The order of decreasing Tg values, ethyl > phenyl > 2-chloroethyl >i-butyl >n-butyl vinyl ether, is the same for both MCP and PDE.

Intrinsic and heat shock induced thermotolerance of Saccharomyces cerevisiae was investigated in cells grown on glucose and acetate supplemented media. Heat shocked cells (37°C/30 min), in either medium, exhibited induced synthesis of heat shock proteins (hsp) and trehalose. In all cases, with the notable exception of repressed cells of a relatively thermosensitive strain, heat shock acquisition of thermotolerance also occurred in the absence of protein synthesis and coincident decrease in trehalose accumulation. Results indicted that the marked increase in thermotolerance exhibited by non-fermenting (acetate) cells compared with fermenting (glucose) cells was not closely correlated with levels of hsp or trehalose. It was concluded that mechanisms for intrinsic and induced thermotolerance appear to be different and that growth on acetate endows cells with a biochemical predisposition, other than hsp or trehalose, that confers intrinsic tolerance, a factor which may be subject to heat induced modification.

This article discusses the quantity of water used by the food waste disposer and the dishwasher. The article discusses a method developed for the approximate determination of water use by a disposer operated at a main pressure that falls within a 10‐180 psi range. Twenty‐six homes were included in a survey that covered a span of 2 years. The article states that the dishwasher has a definite reservoir capacity, a fixed valve arrangement and a repetitive washing and rinsing cycle. Therefore, approximately the same quantity of water is used each time the dishwashing machine is put through a cycle.