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There is evidence to suggest that clathrate hydrates have a significant effect on the surface geology of icy bodies in the Solar System. However the aqueous environments believed to be present on these bodies are likely to be saline rather than pure water. Laboratory work to underpin the properties of clathrates in such environments is lacking. We fill this gap by carrying out a laboratory investigation of the physical properties of CO$_2$ clathrates produced in weak aqueous solutions of MgSO$_4$. We use synchrotron X-ray powder diffraction to investigate clathrates formed at high CO$_2$ pressure in ice that has formed from aqueous solutions of MgSO$_4$. We measure the thermal expansion, density and dissociation properties of the clathrates under temperature conditions similar to those on icy Solar System bodies. We find that the sulphate solution inhibits the formation of clathrates by lowering their dissociation temperatures. Hysteresis is found in the thermal expansion coefficients as clathrates are cooled and heated; we attribute this to the presence of the salt in solution. The density derived from X-ray powder diffraction is temperature and pressure dependent. When comparing the density of CO$_2$ clathrates to that of the solution in which they formed, we conclude that they sink in the oceans in which they form. We also find that the polymorph of ice present at low temperatures is Ih rather than Ic, which we attribute to the presence of the MgSO$_4$. We 1) conclude that the clathrate density has implications for their behaviour in satellite oceans as their sinking and floating capabilities are temperature and pressure dependent, 2) conclude that the presence of MgSO$_4$ inhibits the formation of clathrates and in some cases may even affect their structure and 3) report the dominance of Ih throughout the experimental procedure despite Ic being the stable phase at low temperature., Accepted for publication by Astronomy and Astrophysics on 25 January 2017. Abstract truncated

Samples of amorphous MgSiO_3 annealed at temperature steps leading up to their crystallisation temperature show a rise in photoluminescence activity, peaking at ~450C. The photoluminescence band has a main peak at 595nm and a weaker peak at 624nm. We present laboratory data to show that the maximum in photoluminescence activity is related to substantial structural reordering that occurs within a relatively narrow temperature range. We attribute the origin of the photoluminescence to non-bridging oxygen hole centre defects, which form around ordered nano-sized domain structures as a result of the breakup of tetrahedral connectivity in the disordered inter-domain network, aided by the loss of bonded OH. These defects are removed as crystallisation progresses, resulting in the decrease and eventual loss of photoluminescence. Thermally processed hydrogenated amorphous silicate grains could therefore represent a potential carrier of extended red emission.

A bespoke capillary sample holder is described that attaches to the cold head of a commercially manufactured (PheniX) closed-cycle helium cryostat originally intended for flat-plate geometry. The new holder allows high-resolution synchrotron powder diffraction data to be collected from samples in Debye–Scherrer geometry over the temperature range 11–295 K. To demonstrate that high-quality powder data can be obtained using this new sample holder, structural refinement (Rietveld) and thermal expansion results measured from reference samples (Si and Al) are presented.

Solute concentrations, including major plant nutrients, are surveyed from sampling during 1985–89 in river systems variably influenced by upland Dinantian (Carboniferous) limestone. Concentrations of most ions generally increase downstream, but there are widespread dilution effects after rainy periods for major ions and local depletions of mostly biological origin for major plant nutrients. In the upper reaches, these depletions develop mainly under low flow from the influence of benthic algae and macrophytes; they affect inorganic C as HCO3- plus dissolved gaseous CO2 and soluble reactive forms of Si, N and P. Inflow – outflow differences of an upland lake result from biological influence on these constituents and also Ca+ and K+. Experimental injections of NH4-N, PO4-P and K+were made to an acid headwater of the River Swale, together with Na+ and Cl- as supposed conservative reference ions. Uptake is insignificant for K+ but marked for NH4-N and PO4-P; the residual percentage decreases exponentially with time. Relative rates of net uptake per unit time are greater for P than for NH4-N and larger under conditions of higher flow velocity and benthic algal growth. Although limestone is lacking in some headwater regions, where atmospheric inputs appear to predominate, overall its chemical denudation as Ca2+ and HCO3-provides most of the solute flux downstream, as well as in some karstic headwaters where the highest values are limited by CaCO3 saturation.

Seasonal changes of phytoplankton were followed over 3 years (1985–87) in a shallow, unstratified and calcareous upland lake.The phytoplankton was of low to moderate abundance and generally dominated by phytoflagellates. Seasonality involved a winter minimum of abundance, a spring maximum of diatoms, and often brief increases in summer that included blue-greens, especially the colonial Gloeotrichia echinulata. Some components were of benthic origin. Seasonal growth of the main component of the phytobenthos, Chara globularisvar. virgata, caused a regular summer depletion in lake water of Ca2+ and HCO3 - (alkalinity) by associated CaCO3 deposition, and a more extreme (and unusual) depletion of K+. Chemical analysis of Chara biomass and of underlying sediments indicated a large benthic nutrient stock, much surpassing that represented by the phytoplankton. Growth in this biomass, and the magnitude of water-borne inputs, influenced the removals of Ca2+, K+ and inorganic N. The phytoplankton was probably limited by a low-P medium, to which co-precipitation of phosphate with CaCO3 may have contributed. A vernal depletion of Si was probably limiting to diatom growth, and appeared to be mainly induced by benthic rather than planktonic diatoms. Examples of long-term change in composition of the phytoplankton and phytobenthos are noted and discussed in relation to the interaction of these components, nutrient enrichment, and possible alternative stable states.

The inactivation of ERG3, a gene encoding sterol Δ5,6-desaturase (essential for ergosterol biosynthesis), is a known mechanism of in vitro resistance to azole antifungal drugs in the human pathogen Candida albicans. ERG3 inactivation typically results in loss of filamentation and attenuated virulence in animal models of disseminated candidiasis. In this work, we identified a C. albicans clinical isolate (VSY2) with high-level resistance to azole drugs in vitro and an absence of ergosterol but normal filamentation. Sequencing of ERG3 in VSY2 revealed a double base deletion leading to a premature stop codon and thus a nonfunctional enzyme. The reversion of the double base deletion in the mutant allele (erg3-1) restored ergosterol biosynthesis and full fluconazole susceptibility in VSY2, confirming that ERG3 inactivation was the mechanism of azole resistance. Additionally, the replacement of both ERG3 alleles by erg3-1 in the wild-type strain SC5314 led to the absence of ergosterol and to fluconazole resistance without affecting filamentation. In a mouse model of disseminated candidiasis, the clinical ERG3 mutant VSY2 produced kidney fungal burdens and mouse survival comparable to those obtained with the wild-type control. Interestingly, while VSY2 was resistant to fluconazole both in vitro and in vivo, the ERG3-derived mutant of SC5314 was resistant only in vitro and was less virulent than the wild type. This suggests that VSY2 compensated for the in vivo fitness defect of ERG3 inactivation by a still unknown mechanism(s). Taken together, our results provide evidence that contrary to previous reports inactivation of ERG3 does not necessarily affect filamentation and virulence.

The high-temperature ferromagnetism in Sr${}_{3}$YCo${}_{4}$O${}_{10+\ensuremath{\delta}}$ perovskite, whose origin has been the subject of considerable debate, has been studied by neutron powder diffraction and synchrotron x-ray diffraction measurements. Oxygen vacancy ordering creates a complex pattern of zigzag stripes in the oxygen-deficient CoO${}_{4+\ensuremath{\delta}}$ layers, where the Co ions are found in three distinct coordinations. The symmetry of this unprecedented structural modulation, in conjunction with the existence of different Co spin states, provides a straightforward explanation for the appearance of ferrimagnetism. A model for the magnetic structure compatible with these structural features is proposed, based on the refinement of powder neutron data. The macroscopic moment as a function of temperature that can be calculated from the values of the ordered spins extracted from refinements is in excellent agreement with bulk magnetization. Unlike previous models, a collinear G-type magnetic structure with uncompensated moments due to distinct spin states of Co imposed by different coordination is found.

We present a study of a complex ultra-high-strength Al alloy containing ~40 volume per cent of second-phase particles, ranging in size from nanometres to a few microns. The microstructure has been investigated using scanning electron microscopy and high-resolution synchrotron X-ray diffraction using the I11 beam line at the Diamond Light Source, UK. Powder diffraction was carried out to (i) determine phases present, (ii) quantify the weight per cent of each phase and (iii) quantify size and strain effects in the Al matrix. The high beam quality (i.e. low divergence and wavelength purity) and multi-analysing crystal detectors makes this an ideal instrument to resolve the high peak density and determine the contribution of sample broadening in the complex alloy. Using Pawley and Rietveld full pattern fitting, the intermetallic phases present were determined to be Al3Ti, Al13Cr2 and Al13Fe4. The weight fraction of each phase was calculated from the Rietveld refinements and correlated well with thermodynamic calculations assuming an equilibrium microstructure. Size and strain in the Al matrix was measured from peak broadening using a Double Voigt analysis and showed significant physical broadening due to both size and strain.

The objectives of this study were to examine the effects of feeding zinc-treated soybean meal (Zn-SBM) on ruminal fermentation patterns and duodenal AA flows in steers fed diets based on corn silage and corn. Six steers (385 kg) fitted with ruminal, duodenal, and ileal cannulas were used in a replicated 3 x 3 Latin square design experiment with 14-d periods. Diets were supplemented with solvent-extracted soybean meal (SBM), Zn-SBM, or a 50:50 combination (CP basis) of SBM:Zn-SBM. Ruminal escape N content of SBM and Zn-SBM were 30.0 and 57.0%, respectively, based on 12-h Dacron bag incubation. Protein sources provided approximately 30% of total CP in diets containing 12.6% CP (DM basis). Dry matter intake was equalized throughout the study at 2.2% of average initial BW. Total N flow at the duodenum was similar (P = .47) among treatments, but a trend (P = .15) for increased nonmicrobial N flow occurred when SBM and Zn-SBM were fed in combination. Micobial N flow and true efficiency of microbial CP synthesis were not affected by treatment (P = .87 and .37, respectively). Ruminal fermentation characteristics generally were unaffected (P > .10) by protein source. A positive quadratic response (P < .06) was observed for total and essential AA flows to the small intestine because flows of total and essential AA from ruminally undegraded dietary protein tended (P = .12) to increase when SBM and Zn-SBM were fed in combination. Absorption of AA from the small intestine also showed a positive quadratic (P < .06) response for SBM:Zn-SBM. Microbial AA flow to the small intestine was similar (P = .87) among treatments.(ABSTRACT TRUNCATED AT 250 WORDS)

The objective of this study was to examine the effect of combining ruminally degradable and undegradable CP sources on ruminal microbial protein synthesis and postruminal N and amino acid (AA) flows in steers. Six steers fitted with ruminal, duodenal, and ileal cannulas were fed diets containing corn silage and high-moisture corn supplemented with urea, soybean meal (SBM), dry corn gluten feed (DCGF), a combination of corn gluten meal and blood meal (CB), or SBM and DCGF in combination with CB. Estimated ruminal N escapes for SBM, DCGF, and CB were 32, 25, and 68%, respectively. Supplemental CP sources supplied 35 to 40% of diet CP (12.5% CP diets). Dry matter intake was adjusted to 2.3% of BW for each steer in each period. Total N flow at the duodenum decreased (P < .01) when the diet was supplemented with urea vs other proteins due to decreased (P < .01) flow of nonmicrobial N. However, microbial N and AA flows were greater (P < .05) for urea than for other protein supplements. Disappearance of OM and NDF in the stomach decreased (P < .07) or was numerically lower but nonmicrobial N at the duodenum increased (P < .08) as CB replaced SBM or DCGF in the diet. Protein source had little effect on ruminal fermentation characteristics except that ruminal ammonia N (NH3N) concentration was higher (P < .05) for urea than for other treatments. Total AA and essential AA flows to and disappearance from the small intestine increased (P < .06) as CB replaced DCGF. However, substituting CB for SBM had little effect on intestinal flows and disappearance of AA. These data suggest that source of ruminally degradable CP can influence the efficacy of feeding ruminally degradable and undegradable CP in combination. In general, source of supplemental CP had a greater effect on the quantity than on the profile of absorbable AA supplied to the duodenum.

1. Tucaresol (589C80; 4[2-formyl-3-hydroxyphenoxymethyl] benzoic acid) interacts stoichiometrically with haemoglobin to increase oxygen affinity. By decreasing the proportion of insoluble deoxy sickle haemoglobin at capillary oxygen concentrations, tucaresol may be of therapeutic benefit in sickle cell anaemia. 2. In this study, which involved the first administration to man, the pharmacokinetics and pharmacodynamics of tucaresol were studied in healthy male volunteers following oral doses of 200-3600 mg. 3. Peak drug concentrations in plasma and erythrocytes were linearly related to dose; mean (s.d.) values were 95.8 (26.1) and 1035 (67) micrograms ml-1, respectively, at the highest dose. Median tmax in plasma was 6.5 h and in erythrocytes 24.5 h, when approximately 60% of the administered dose was in the target tissue. Plasma drug concentrations fell biexponentially with commencement of the apparent terminal elimination phase at approximately 24 h. The terminal elimination half-life from plasma increased with dose (r = 0.77; P < 0.0001) from 133-190 h at 400 mg to a mean (s.d.) of 289 (30) h at 3600 mg. Erythrocyte drug concentrations declined mono-exponentially with a half-life that was always shorter than the apparent terminal half-life in plasma: overall mean (95% CI) of t1/2 erythrocyte/t1/2 plasma ratio was 0.57 (0.53, 0.61). The erythrocyte AUC/plasma AUC ratio increased with dose (r = 0.67; P < 0.001). 4. The proportion of haemoglobin modified to a form with high oxygen affinity (%MOD) increased in a dose-related manner above doses of 800 mg reaching 19-26% after the 3600 mg dose.(ABSTRACT TRUNCATED AT 250 WORDS)

The compounds (Ti1-xZrx) (HPO4)2·H2O (x = 0—1) are synthesized from aqueous solutions of TiCl4, ZrOCl2, and H3PO4 (autoclave, 150 °C, 7 d) and characterized by synchrotron powder XRD and pair distribution function analysis of high energy synchrotron X-ray total scattering data.

Molecular genetic approaches were adopted in the model crucifer, Arabidopsis thaliana, to unravel components of RPP5- and RPP1-mediated disease resistance to the oomycete pathogen, Peronospora parasitica. The products of RPP5 and three genes comprising the RPP1 complex locus belong to a major subclass of nucleotide-binding/leucine-rich repeat (NB-LRR) resistance (R) protein that has amino-terminal homology to the cytoplasmic domains of Drosophila and mammalian Toll and interleukin-1 family receptors (the so called 'TIR' domain). Similarities in the domain architecture of these proteins and animal regulators of programmed cell death have also been observed. Mutational screens revealed a number of genes that are required for RPP5-conditioned resistance. Among these are EDS1 and PAD4. Both EDS1 and PAD4 precede the function of salicylic acid-mediated plant responses. The EDS1 and PAD4 genes were cloned and found to encode proteins with similarity to the catalytic site of eukaryotic lipases, suggesting that they may function by hydrolysing a lipid-based substrate.

Anhydrides derived from tall oil fatty acids offer enhanced corrosion inhibition properties compared to traditional dimer/trimer acids. The chemistry of this intermediate, its use in corrosion inhibition for downhole applications, and the synthesis of novel oil- and water-soluble derivatives were studied.

A mitochondrial sulphonylurea-sensitive, ATP-sensitive K+ channel (mitoKATP) that is selectively inhibited by 5-hydroxydecanoate (5-HD) and activated by diazoxide has been implicated in ischaemic preconditioning. Here we re-evaluate the evidence for the existence of this mitoKATP by measuring changes in light scattering (A520) in parallel with direct determination of mitochondrial matrix volumes using 3H2O and [14C]sucrose. Incubation of rat liver and heart mitochondria in KCl medium containing Mg2+ and inorganic phosphate caused a decrease in light scattering over 5 min, which was accompanied by a small (15-30 %) increase in matrix volume. The presence of ATP or ADP in the buffer from the start greatly inhibited the decline in A520, whilst addition after a period of incubation (1-5 min) induced a rapid increase in A520, especially in heart mitochondria. Neither response was accompanied by a change in matrix volume, as measured isotopically. However, the effects of ATP and ADP on A520 were abolished by carboxyatractyloside and bongkrekic acid, inhibitors of the adenine nucleotide translocase (ANT) that lock the transporter in two discrete conformations and cause distinct changes in A520 in their own right. These data suggest that rather than matrix volume changes, the effects of ATP and ADP on A520 reflect changes in mitochondrial shape induced by conformational changes in the ANT. Furthermore, we were unable to demonstrate either a decrease in A520 or increase in matrix volume with a range of ATP-sensitive K+ channel openers such as diazoxide. Nor did glibencamide or 5-HD cause any reduction of matrix volume, whereas the K+ ionophore valinomycin (0.2 nM), produced a 10-20 % increase in matrix volume that was readily detectable by both techniques. Our data argue against the existence of a sulphonylurea-inhibitable mitoKATP channel.

Plant disease resistance (R) genes are introduced into high yielding crop varieties to improve resistance to agronomically important pathogens. The R gene-encoded proteins are recognitionally specific, interacting directly or indirectly with corresponding pathogen avirulence (avr) determinants, and are therefore under strong diversifying selection pressure to evolve new recognition capabilities. Genetic analyses in different plant species have also revealed more broadly recruited resistance signalling genes that provide further targets for manipulation in crop improvement strategies. Understanding the processes that regulate both plant-pathogen recognition and the induction of appropriate defences should provide fresh perspectives in combating plant disease. Many recent studies have utilized the model plant, Arabidopsis thaliana. Here, mutational screens have identified genes that are required for R gene function and for restriction of pathogen growth in compatible plant-pathogen interactions. Genetic analyses of these plant mutants suggest that whilst signalling pathways are conditioned by particular R protein structural types they are also influenced by pathogen lifestyle. Two Arabidopsis defence signalling genes, EDS1 and PAD4, are required for the accumulation of salicylic acid, a phenolic molecule required for systemic immunity. The cloning, molecular and biochemical characterization of these components suggests processes that may be important in their disease resistance signalling roles.

A cluster of biopsy-confirmed interstitial lung disease among workers at a nylon flock plant led to a request for National Institute for Occupational Safety and Health investigators to conduct a health hazard evaluation.Part of the overall evaluation, reported here, involved a cross-sectional medical survey of current employees. The survey consisted of a questionnaire, spirometry and diffusing capacity testing, and chest radiograph.Workers assigned to production and maintenance jobs reported frequent eye and throat irritation, respiratory symptoms, and systemic symptoms (i.e., generalized aches and fevers). Most reported improvement when away from work. Frequent respiratory/systemic symptom prevalence was significantly associated with departmental category, with days and hours worked per week, and with working on a flocking range. Compared to asymptomatic workers, symptomatic workers had similar mean ratios of forced expiratory volume in one second to forced vital capacity, but lower mean percent of predicted values for both forced vital capacity and diffusing capacity. All acceptable chest radiographs were classified as category 0 for small opacities.Findings of this study, along with those from studies reported elsewhere, implicate occupational exposure to flock-associated dust as a significant respiratory health hazard at this plant.

In Arabidopsis ecotype Landsberg erecta (Ler), RPP5 confers resistance to the pathogen Peronospora parasitica. RPP5 is part of a clustered multigene family encoding nucleotide binding-leucine-rich repeat (LRR) proteins. We compared 95 kb of DNA sequence carrying the Ler RPP5 haplotype with the corresponding 90 kb of Arabidopsis ecotype Columbia (Col-0). Relative to the remainder of the genome, the Ler and Col-0 RPP5 haplotypes exhibit remarkable intraspecific polymorphism. The RPP5 gene family probably evolved by extensive recombination between LRRs from an RPP5-like progenitor that carried only eight LRRs. Most members have variable LRR configurations and encode different numbers of LRRs. Although many members carry retroelement insertions or frameshift mutations, codon usage analysis suggests that regions of the genes have been subject to purifying or diversifying selection, indicating that these genes were, or are, functional. The RPP5 haplotypes thus carry dynamic gene clusters with the potential to adapt rapidly to novel pathogen variants by gene duplication and modification of recognition capacity. We propose that the extremely high level of polymorphism at this complex resistance locus is maintained by frequency-dependent selection.

Intense flashes of light were observed in sodium bicarbonate and hydrogen peroxide solutions when they were exposed to pulsed microwave radiation, and the response was greatly enhanced by a microwave-absorbing, biosynthesized polymer, diazoluminomelanin. A FPS-7B radar transmitter, operating at 1.25 GHz provided pulses of 5.73 +/- 0.09 micros in duration at 10.00 +/- 0.03 pulses/s with 2.07 +/- 0.08 MW forward power (mean +/- standard deviation), induced the effect but only when the appropriate chemical interaction was present. This phenomenon involves acoustic wave generation, bubble formation, pulsed luminescence, ionized gas ejection, and electrical discharge. The use of pulsed microwave radiation to generate highly focused energy deposition opens up the possibility of a variety of biomedical applications, including targeting killing of microbes or eukaryotic cells. The full range of microwave intensities and frequencies that induce these effects has yet to be explored and, therefore, the health and safety implications of generating the phenomena in living tissues remain an open question.

Since 1985, the Louisiana State University School of Medicine in New Orleans, through its Office of Community and Minority Health Education, has operated the Summer Science Program for Louisiana high school students from underrepresented minorities. The authors conducted a survey during the 1997-98 academic year of the 773 students who had participated in the summer program from 1985 to 1997. The goal was to learn what education and career paths these students had taken since leaving the program. A total of 665 students (89.4%) responded. Sixty-one were still in high school, 11 had not continued their education after completing high school, but 432 of the remaining 583 students had chosen education paths in medicine, another health profession, or science, and 31 were enrolled in or had graduated from medical school. These findings indicate that the majority of the summer program students had maintained the health and/or science career interests they had expressed during their time in the program. Future studies will use control groups to better ascertain how influential the summer program was in helping students choose and maintain science and health education and career paths.

We performed flow cytometric analysis of CD34+ cell apoptosis in 59 patients with myelodysplastic syndrome (MDS) or acute myeloid leukaemia (AML) secondary to MDS (MDS-AML) using annexin V-FITC, which binds to exposed phosphatidylserine on apoptotic cells. Apoptosis was significantly increased in FAB subtypes RA, RARS and RAEB (10% blasts) (56.5% (15.1-86.5%)) compared to normal controls (18.5% (3.4-33.4%), P0.0001) and RAEB-t/MDS-AML (16% (2.1-43.2%), P0.0001). There was no correlation between % apoptosis, Full blood count or cytogenetics in any disease category. Two-colour cytometric analysis of permeabilized CD34+ cells stained with antibodies to Bcl-2, Bcl-X (anti-apoptotic), Bax and Bad (pro-apoptotic), demonstrated significantly higher ratios of pro- v anti-apoptotic proteins in early MDS (2.47 (1.19-9.42) compared to advanced disease (1.14 (0.06-3.32), P=0.0001). Moreover, using repeated measures of variants (ANOVA), we found that variations between individual Bcl-2-related proteins differed significantly according to disease subtype (P0.0005). Our results confirm that CD34+ cell apoptosis was significantly increased in MDS subtypes RA and RARS and fell with disease progression. Early MDS was also associated with a significantly higher CD34+ cell pro- v anti-apoptotic Bcl-2-family-protein ratio than advanced disease. Furthermore, patterns of expression of individual Bcl-2 related proteins differed significantly between different disease categories. However, no correlation between pro- v anti-apoptotic Bcl-2-family-protein ratios and the degree of apoptosis was observed.

Electrochemiluminescence (ECL) studies of the chemiluminescent (CL) polymer diazoluminomelanin (DALM) biosynthesized in nitrate reductase transfected Escherichia coli JM109 bacteria revealed noteworthy anodic ECL and even more intense cathodic ECL. Bacterial DALM (BD) ECL was also assessed in the presence of 100 ppm of 33 different metal and non-metal ions which revealed specific anodic, but not cathodic, enhancements of BD ECL with Ag+, Hg2+ and Ru3+. The precursors and intermediate polymers which comprise DALM, such as luminol, 3-amino-L-tyrosine (3-AT), aminomelanin (AM) and diazomelanin (DM) were screened for ECL enhancement against the same set of elemental ions. Significant anodic ECL enhancements were observed for luminol with Hg2+ in the presence of tripropylamine (TPA), but not for any other DALM component in combination with other elemental ions, either anodically or cathodically. Comparison of BD with luminol in the presence and absence of TPA and Hg2+ revealed very different ECL activity patterns and suggested different mechanisms for BD and luminol ECL.

A 5-year-old Quarter Horse stallion was admitted for cryptorchidectomy. Abnormalities were not found on physical examination, except for an undescended left testis. Cryptorchidectomy was performed, using an inguinal approach. The tail of the epididymis was in the inguinal canal, and the testis was adjacent to the internal inguinal ring. The testis was dark reddish purple to black, resulting from torsion at the level of the body of the epididymis. On histologic examination, the left testis was necrotic, except for the tunica albuginea and tunica vaginalis visceralis covering the testis. Intra-abdominal testicular torsion developed without signs of abdominal pain and resulted in necrosis of the affected testis. If cryptorchidectomy had not been performed, it is likely that the horse would have been found to be monorchid. Unrecognized intra-abdominal testicular torsion may be the cause of monorchidism in some horses.

The phase stability and compatibility of intermediate temperature solid oxide fuel cell (IT-SOFC) composite cathodes of lanthanum nickelate, La2NiO4+δ (LNO), and ceria-gadolinium oxide, Ce0.9Gd0.1O2−δ (CGO10), have been investigated by high resolution synchrotron X-ray diffraction (XRD). No reaction was observed between LNO and CGO10 at temperatures of up to 900 °C when the composite is open to an ambient air environment. However, in a sealed capillary environment the 50:50 wt% LNO:CGO10 composite undergoes a partially reversible reaction at temperatures of 750 °C and above, whereby LNO decomposes to La2O3 and Ni. Changes in the CGO10 Bragg peaks indicate that this component is actively involved in this process. This study shows that the phase stability of LNO:CGO10 composites is highly dependent on oxygen partial pressure. In addition, it is observed that ex-situXRD is insufficient to determine the presence of reactivity in composite cathodes and that high resolution in situXRD measurements are required to obtain details of the complexity of phase stability in SOFC composite cathodes.

In situ X-ray diffraction coupled with Rietveld refinement has been used to study CO2 capture by CaO, Ca(OH)2 and partially hydrated CaO, as a function of temperature. Phase quantification by Rietveld refinement was performed to monitor the conversion to CaCO3 and the results were compared to those derived using thermogravimetric analysis (TGA). It was found that Ca(OH)2 converted directly to 100% CaCO3 without the formation of a CaO intermediate, at ca. 600 °C. Both pure CaO and partially hydrated CaO (33.6 wt% Ca(OH)2) reached the same capture capacity, containing approximately 65 wt% CaCO3 at 800 °C. It was possible to provide direct evidence of the capture mechanism. The stresses in the Ca(OH)2 phase of the partially hydrated CaO were found to be more than 20 times higher than its strength, leading to disintegration and the generation of nano-sized crystallites. The crystallite size determined using diffraction (75 × 16 nm) was in good agreement with the average crystallite size observed using TEM (of 83 × 16 nm). Electron diffraction patterns confirmed coexistence of CaO and Ca(OH)2. The analysis provides an explanation of the enhanced capture/disintegration observed in CaO in the presence of steam.

The in vitro precipitation of the metastable CaCO3 phases aragonite and vaterite in the presence of leucine is investigated. Under normal conditions, the production of CaCO3 via the hydrolysis of urea method favours the formation of regular needle-like aragonite crystals, with very minor quantities of vaterite and calcite. However in the presence of leucine, aragonite forms highly branched structures and the vaterite yield is increased, forming flower-like clusters composed of nano-thin sheets. Both the degree of aragonite branching and the occurrence, regularity of shape and number of vaterite "petals" increases with leucine concentration. The two phases exhibit different variations in their crystallographic parameters with increasing concentration, while the molecular structure appears unaffected.

1. Artists use many materials composed of the same chemicals that cause major occupational health problems in industry. 2. The majority of artists are unaware of the potential hazards in the materials and processes they use. 3. The pilot study revealed that greater than 90% of the amateur photographers did not use safety precautions in the darkroom. 4. The most common perceived barrier to the use of safety precautions was the lack of knowledge about chemical safety.

Since the early 1900s, it was recognized that many dust-exposed workers developed abnormal radiographs during life. Chest radiography remains the primary means of determining the presence and extent of dust-induced pneumoconiosis, although it is ineffective for detecting airways obstructions from mine dust exposure. This chapter reviews the uses and limitations of chest radiography in the study, surveillance, screening, clinical diagnosis, and disability determinations of occupational lung diseases in dust-exposed workers.

CWP is a disease distinct and separate from silicosis. Simple CWP is clearly related to the amount of dust deposited within the lungs. Complicated CWP (PMF) results from dust deposition plus other factors. Immunologic and local cellular factors may contribute to the development of this form of the disease. Studies of lung cell response and function may further elucidate mechanisms and mediators of lung dust reaction. Complicated CWP (PMF) is clearly associated with alterations in ventilatory, mechanical, and vascular function of the lungs. These abnormalities in PMF contribute to the observed premature morbidity and mortality of this disease.

SUMMARY The effects of infection by spinach latent (SLV) and arabis mosaic virus (AMV) upon flowering, seed production and seed vigour, were studied in Nicotiana and Chenopodium species. Infection frequently caused mother-plants to produce flowers earlier than healthy plants, and AMV induced C. amaranticolor Coste & Reyn., which normally flowers only under 'short-day' conditions, to flower in 'long-days'. Infection with SLV or AMV generally caused a significant reduction in normal seed numbers and a corresponding increase in aborted seed. Mean seed weights were often lower from infected than from healthy plants, but in some infections lower seed production was correlated with a compensatory increase in the weight of individual seeds. The viability of seeds from infected plants was slightly reduced in some instances but, even when seed viability was not affected, tests of accelerated ageing indicated that seed vigour was impaired.

SUMMARY This study considered the relationship between extraversion and the recall of details in prose passages under conditions of two levels of detail importance (main and elaboration), two types of passage (thematic and sequential) and two degrees of interference (absent and present). The subjects were 96 11‐year old children who were divided into introverts, ambiverts and extraverts on the basis of their score on the Junior Eysenck Personality Inventory. A different extraversion subgroup listened to a prose passage containing 40 details under each of the experimental conditions and one hour later was required to free recall the material. Overall recall performance was not significantly affected by extraversion, but there was a significant interaction (P < 0.05) between extraversion and detail type in their effect on recall. Generally the recall of elaborative detail decreased with increasing extraversion, while for the main detail recall remained fairly constant. No other significant interactions were...

The purpose of this study is to examine the feasibility of practical wave energy conversion using an oscillating water column (OWC) and a counter-rotating turbine on a fixed offshore platform. A linear array of such platforms along a coastline, with the power transmitted ashore by submarine cable, constitutes the type of wave energy powerplant discussed herein. The OWC concept utilizes the energy in a wave field to cause the sea, trapped within a cavity in a fixed or floating housing, to oscillate vertically within the cavity, thereby alternately pushing and pulling the air in the cavity through a turbine mounted at an opening in the cavity, thus converting wave energy to usable power. The design, maintenance, and economic aspects of the wave energy powerplant described in the foregoing are discussed for siting around England and Scotland. Gravity, piled, and caisson platform designs are considered in light of current offshore petroleum industry practices and capabilities. Wave energy researchers have made little effort to use proven offshore fixed structure technology, developed by the offshore petroleum industry, in studying ways to house a wave energy conversion device. Such a combination was suggested by McCormick in 1974 and is the subject of this study.

IN A previous paper on wood sugar molasses as a feedstuff for laying hens (Cooney and Parker, 1952) it was pointed out that cane and beet molasses have been accepted and used as an ingredient in livestock and poultry rations for a good many years. The review of literature indicated that these products could be fed up to ten percent of the chicken’s total ration. However, levels of five to seven percent of the total ration seemed to be more generally accepted. McGinnis, MacGregor and Carver (1948) were the first to report on the use of molasses prepared from wood waste in poultry rations. They fed levels of 0, 5, 10, 15, and 20 percent of this product to duplicate lots of one week old New Hampshire chicks over a three-week test period. From this work they concluded that wood sugar molasses could be used in chick rations at any …

CHICKENS cannot survive very long when deprived of water. A ten percent loss of body water through dehydration and excretion results in serious physical disorders (Romanoff and Romanoff, 1949). Dehydration is particularly noticeable in the shanks, and some mortality may result as reported by Marble and Jeffrey (1955). Hoffman and Johnson (1946) reported chicks that have been without water can be readily identified because in their eagerness to drink they wet their plumage and have a bedraggled appearance for some time afterward. Kare and Biely (1948) placed New Hampshire chicks on diets containing .9 to 4.0 percent salt, and deprived them of water four to six hours per day. The water-restricted chicks compensated by drinking more when water was before them which resulted in approximately the same water:feed ratios as the controls with water ad libitum. In a study conducted by Ross (1960) one-week-old New Hampshire chicks were given…

DEVELOPMENT of a refractory condition leading to failure of the junco to produce eggs in an environment of long light days was observed by Wolfson (1952). A similar inability of turkey females to respond in egg production when exposed to long light days was reported by Harper and Parker (1957, 1960, 1962), Clayton and Robertson (1960), McCartney et al. (1961), Leighton and Shoffner (1961a, b, 1964), Wilson et al. (1962) Shoffner and Leighton (1962), Shoffner et al. (1962), Marsden et al. (1962), Ogasawara et al. (1962), and Wolford et al. (1963). In the above research control of the photoperiod to reduce light exposure prior to sexual maturity of turkey females was effective in terminating refractoriness. While the above experiments demonstrated a method of improving year around egg production of turkeys through a controlled light environment, it necessitated adequate buildings. The use of hormones to terminate refractoriness in turkey females hatched…

ALTHOUGH numerous studies concerned with photoperiodism on the sexual development of female chickens have been reported, most of them have involved Leghorn type birds and have been limited to the influence of lights during the rearing period. Also, most studies have limited light restriction to 6 or 8 hours although Rider (1938) and King (1961, 1962) reported pullets reared in darkness would come into egg production. Parker and McCluskey (1961) reported onset of semen production in cockerels on as little as a 1 hour single light period per day. This study involved heavy breed pullets reared and maintained on light periods as short as 1 hour per day. MATERIALS AND METHODS Chicks used in this experiment consisted of 21 Delaware pullets per treatment hatched November 11, 1961, from a flock maintained at the Oregon Agricultural Experiment Station. They were reared from time of hatch on 1, 3, 9 and 13…