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Yield response of summer cabbage (Brassica oleracea varcapitata cv. Hispi F1) to N applied as organic (activated sewage sludge derived protein [Protox] and dried blood) and inorganic (ammonium nitrate, ammonium sulphate, sodium nitrate and urea) fertilizers was compared in relation to the N availability characteristics of the materials. Effects of the nitrification inhibitor dicyandiamide (DCD) on N release, crop yield and N status were also assessed. In addition CO2 efflux was measured from amended soil to determine effects of fertilizer application on soil microbial activity. The organic N sources were mineralized quickly on application to soil and exhibited similar patterns of NH4-N depletion and NO3-N accumulation as functions of thermal-time as with mineral fertilizers. However, the yield response to organic N was marginally smaller (though not significantly) compared with mineral forms; probably because less N was released to the crop. This was reflected in smaller total N concentrations and N recoveries in plants supplied with organic fertilizer. Applied DCD increased the thermal-time for complete nitrification of NH4-N sources and raised the total N content of the crop, but had no overall effect on crop growth. In contrast to inorganic N sources which generally reduced CO2 efflux from soil, application of protein-based fertilizers increased the rate of soil microbial activity directly by raising substrate availability. Sewage sludge derived protein provided an effective alternative to mineral fertilizers for the nutrition of summer cabbage whilst minimising stress of the soil environment which may occur following the application of conventional forms of inorganic N to the soil.

We report measurements of the ratios {ital K}{sup +}/{pi}{sup +}, {ital p}/{pi}{sup +}, {ital K}{sup {minus}}/{pi}{sup {minus}}, {ital {bar p}}/{pi}{sup {minus}}, {pi}{sup {minus}}/{pi}{sup +}, {ital K}{sup {minus}}/{ital K}{sup +}, and {ital {bar p}}/{ital p} for hadrons with 0.19{lt}{ital x}{sub {ital t}}{lt}0.62 produced in {ital p}-Be and {ital p}-W collisions at {radical}{ital s} =38.8 GeV. The {ital K}{sup +}/{pi}{sup +} ratio at high {ital x}{sub {ital t}} gives the fragmentation-function ratio {ital D}{sub {ital u}}{sup {ital K}+}/{ital D}{sub {ital u}}{sup {pi}+} at high {ital z}. The high-{ital x}{sub {ital t}} {ital K}{sup {minus}}/{pi}{sup {minus}} ratio gives an upper limit for {ital D}{sub {ital d}}{sup {ital K}{minus}}/{ital D}{sub {ital d}}{sup {pi}{minus}} at high {ital z}. The {ital p}{sub {ital t}} dependence of {ital p}/{pi}{sup +} suggests that scattered constituent diquarks are the primary source of protons with {ital p}{sub {ital t}}{lt}6 GeV/{ital c}. We also present species correlations in high-mass {ital h}{sup +}{ital h{minus}} pairs. Strong {ital K}{sup +}{ital K{minus}} and {ital p{bar p}} correlations were observed.

Maternal hyperthermia of short duration had significant short and long term effects on the developing guinea-pig eye at embryonic days 19, 21 and 23. A marked regionalisation of the heat-induced effects was observed in the developing retinae, but the lens defects were most obvious following heat at E21 and E23. Bilateral anterior pole cataracts, bipolar zonular cataracts and microphthalmia have been produced following maternal heat stress. It is suggested that these are determined by the cellular events initiated in the developing eye following the teratogenic insult.

The results of the present study indicate that, for the most part, the variety of C-S bonded structures formed in TMTD-vulcanized cis-BR qualitatively parallel those found in sulfur-cured vulcanizates of the material. Key exceptions include the demonstrated existence of stable rubber-bound accelerator fragments, and the possible elimination of select intramolecular cyclic species. Cis-to-trans isomerization has again been shown to be the predominant feature of the vulcanization reaction sequence and seems to obey first-order kinetics with respect to the concentration of accelerator. While the kinetic rate of conversion among all intermediate species was too rapid to permit a full account of the process, the spectral data demonstrate further that, subsequent to the formation of rubber-bound accelerator residues, sulfur becomes quickly redistributed to form crosslink structures of low average sulfur rank. In contrast to results obtained from elemental sulfur-cured BR vulcanizates, relatively high concentrations of monosulfidic crosslink structures were found in the TMTD vulcanizates at even the shortest reaction times. Similar to the results of the sulfur study, on the other hand, comparison between chemical and physical crosslink densities of the samples indicate the reaction sequence to have been highly localized, producing spatially inhomogeneous networks of elastically inefficient, clustered crosslinks. This latter result can be taken to imply that network morphology in TMTD-vulcanized BR is critically influenced by the solubility of the active accelerator complex in the rubber matrix. The effect was exaggerated in the present study by the omission of a compatible chelating agent for the zinc ions. From the standpoint of efforts aimed at optimization and control of the performance properties of vulcanized rubber articles, systematic investigation of the dependence of this effect on a wider range of formulation variables is warranted.

Pixel by pixel T1 mapping of MR images has been used in conjunction with image analysis techniques to study the lumbar vertebral bone marrow of 20 patients with refractory or relapsed Hodgkin's disease prior to salvage chemotherapy, or high dose chemotherapy with autologous bone marrow rescue. Compared to 18 age matched controls, seven patients had significantly abnormal lumbar vertebral marrow T1 histograms with median, 5% and 95% centile T1 values that lay outside a three dimensional 95% probability region obtained for the normals. Six of these patients had increased areas of high T1 consistent with bone marrow involvement with lymphoma; although, only in two of them had Hodgkin's disease been detected by bilateral iliac crest bone marrow biopsy. Post-treatment studies were performed in four patients who had abnormal areas of high T1 in the lumbar vertebral bone marrow. All showed normalisation of the T1 histogram, with a reduction of T1 values to within the normal range as defined by the studies of age matched controls. T1 mapping of bone marrow offers potential for detecting bone marrow infiltrates in patients with lymphoma, and also for the assessment of treatment response. Images Figure 6 Figure 7

Deep levels between 0.1 and 1.0 eV in semi‐insulating and high resistivity undoped horizontal Bridgman GaAs have been studied by temperature‐dependent Hall effect (TDH) and Fourier transform photoconductivity (FTPC). Activation energies at 0.77, 0.426, and 0.15 eV have been observed by TDH. Photoionization thresholds at 1.0, 0.8, 0.56, 0.44, and 0.25 are reported. The photoconductivity thresholds at 0.56 and 0.25 eV are reported for the first time. New features in the 0.44 eV threshold suggest that the defect responsible for this level has a small lattice relaxation and Frank–Condon shift. Possible associations of the FTPC and TDH energies with the deep‐level transient spectroscopy levels EL2, EL3, and EL6 are presented.

Guinea pigs were exposed to hyperthermia for 1 hr once or twice on day 11, 12, 13, or 14 (E11-E14) of pregnancy. The mean rectal temperatures were elevated by 3.4 degrees C-4.0 degrees C. This treatment resulted in a marked elevation of rates of resorption and developmental defects in embryos examined at day E23. The defects observed were those affecting the neural tube (NTD) (exencephaly, encephaloceles, and microphthalmia), kyphosis/scoliosis, branchial arch defects, and pericardial edema. Embryos with NTD and kyphosis/scoliosis have not been found among newborn guinea pigs to date following maternal heat exposure on days E12-E14. It appears that embryos with these defects are filtered out by resorption or abortion by days E30-E35.

The size of adipocytes influences their function suggesting a differential responsiveness to intervention. We hypothesized that weight loss in patients with type 2 diabetes mellitus (T2DM) predominantly decreases the size of large and very-large adipocyte subfractions in parallel with beneficial changes in serum adipokines and improved insulin sensitivity. A total of 44 volunteers from the Look Action for Health in Diabetes trial, who lost weight after 1-year of intense lifestyle intervention, were included. Insulin sensitivity (hyperinsulinemic-euglycemic clamp), size of subcutaneous abdominal adipocytes (osmium fixation), and selected serum adipokines were measured. A 13% weight loss was accompanied by 46% improvement in insulin sensitivity (increased glucose disposal rate from 5.9+/-2.2 to 8.6+/-2.7 mg/min/kg fat-free mass, P

Three adult lactating Holstein cows were injected in the subcutaneous abdominal vein with 175 ng/kg of body weight of Clostridium botulinum type C toxin (451 cow median toxic doses) to determine if this botulinum toxin crosses the blood-milk barrier. Whole blood (in sodium heparin) and clotted blood serum samples were taken at 0 min, 10 min, and 3, 6, 9, and 12 h postinoculation. Milk samples were taken at 0 min and at 3, 6, 9 and 12 h postinoculation. All samples were tested for the presence of the toxin using the mouse bioassay and immunostick ELISA test. The immunostick ELISA identified the toxin in whole blood and the mouse bioassay identified the toxin in serum at all times examined in all 3 animals. Toxin was not identified by either detection method in milk samples collected from the 3 animals. From these results, it appears that Clostridium botulinum type C toxin does not cross from the blood to the milk in detectable concentrations.

The allotropic transformation of cobalt was studied with a differential scanning calorimeter. The temperatures of the fcc to hep transformation, As, and fcc to hcp transformation, Ms, exhibit a linear dependence on the heating and cooling rates: As(K) = 723.2 + 0.28R and Ms(K) = 671.4-0.28R whereR is the rate in K/min. As, Ms, and the associated enthalpies of the phase changes were observed to increase with increasing number of cycles through the transformation. The Ms reaction was observed to proceed slowly isothermally while exhibiting athermal behavior when cooled rapidly.

Serial image-localized 31P magnetic resonance spectroscopy studies were performed in nine patients with newly diagnosed non-Hodgkin's lymphoma (NHL) during the early part of treatment with chemotherapy. The pre-treatment intracellular pH (pHi) of the tumours ranged from 6.97 to 7.61 for high-grade NHL (n = 3), and 7.16 to 7.39 for low-grade NHL (n = 5). A pH of 7.24 was recorded in a patient with intermediate-grade NHL. Slice-to-slice variation in tumour pHi in spectra obtained with a one-dimensional chemical shift imaging (1D-CSI) technique varied from zero to 0.5 pH units. The largest variation was seen in high-grade tumours. Slice-to-slice variation may reflect tumour heterogeneity. Alkaline shifts in tumour pHi of 0.14 to 0.45 pH units were seen in six patients following chemotherapy. Maximal change in tumour pH was related temporally to increases in the phosphodiester/beta-adenosine triphosphate ratio, and occurred before alterations in tumour size were documented. Cell death and necrosis may be associated with an alkaline shift in pHi due to cessation of H(+)-producing processes and release of basic components of proteins. An alkaline shift in tumour pHi may therefore be an early metabolic marker of response to chemotherapy.

Tetramethylthiuram disulfide-vulcanized cis-polybutadiene samples of different cross-link densities were swollen with deuterated solvent and directly imaged, using single and multiple spin-echo NMR imaging (NMRI) pulse sequences. Major structural voids, compression- and reaction-induced gradients of chain segment mobility, and general spatial inhomogeneity in the cross-link density of these samples have been observed. A simple analytical model has been applied to interpret changes in the distribution of T 2 values with increasing cure time

Experimental results on the production of dimuons by 800-GeV protons incident on a copper target are presented. The results include measurements of both the continuum of dimuons and the dimuon decays of the three lowest-mass $\ensuremath{\Upsilon}$ $S$ states. A description of the apparatus, data acquisition, and analysis techniques is included. A comparison of the results with data taken at lower incident energies indicates a scaling behavior of the continuum dimuon yields.

Lumbar vertebral (LV) bone marrow proton relaxation times were measured from midline sagittal magnetic resonance images of the lumbar spine of 20 patients with refractory or relapsed Hodgkin’s disease (HD) referred for autologous bone marrow transplantation (ABMT) and 18 aged-matched normal volunteers.

Because internal and external fixation devices alter blood flow, and thus the transport of nutrients to the cortical bone of a healing fracture, we studied the effects of a fluted intramedullary rod (IMR), a half-frame external fixator (EF), and a compression plate (PL) on the cortical bone directly adjacent to the fracture site at 4 and 48 h and 14 and 90 days after fixation. Three specific areas of cortical bone were studied: endosteal cortex, periosteal cortex, and subplate cortex (cortical bone under the compression plate). The fractures fixed with IMR had the lowest blood flow at all time periods studied. At 4 h, the difference between IMR and PL or EF was statistically significant in the endosteal cortex (p less than 0.01 or p less than 0.05, respectively); also, the difference between the IMR and EF in the subplate cortical bone region was significant (p less than 0.05). At 14 days, the blood flow to the endosteal cortex was still significantly lower with IMR than with EF (p less than 0.025). At 90 days, the blood flow to the subplate region of cortical bone was significantly (p less than 0.02) higher with PL than with IMR but there was no significant difference in bone remodeling with the different fixation devices.

The C and N mineralization characteristics of two organic N fertilizers were determined in a soil-less incubation system at three temperature regimes. Protox (derived from activated sewage sludge) initially degraded more rapidly by microbial action compared with dried blood. However, dried blood released more CO2-C and inorganic N towards the end of the incubation periods. The rate of microbial degradation increased with temperature. Mineralization characteristics of protein-based N sources are discussed in relation to organic N nutrition of vegetable crops.

To determine the fate of the enteric indicator organism, Escherichia coli, in sewage sludge (biosolids)-amended agricultural soil in relation to soil type and moisture status under controlled conditions.We enumerated Escherichia coli in soil by membrane filtration and most probable number techniques. The background concentration of E. coli was higher in sandy loam than in silty clay soil. E. coli numbers increased in soil following addition of dewatered, mesophilic anaerobically digested sludge. Escherichia coli declined to a small extent with time in both moist and air-dried unamended control soils, although decay was only highly significant (P0.001) in moist sandy loam (T(90) = 100 days). Removal rates were high in sludge-treated moist soil (T(90) = 20 days), but were significantly reduced in amended air-dried soil.Slow removal of E. coli in air-dried soil as against their rapid decay in moist soil after sludge application indicated that the soil biota are involved in pathogen reduction processes in sludge-amended soil.Soil ecological mechanisms are implicated as having a critical role in the fate of enteric organisms introduced into temperate agricultural soil in sewage sludge.

To measure the survival of enteric micro-organisms in agricultural soil amended with conventional and enhanced treated biosolids in relation to environmental and edaphic conditions.Escherichia coli, Salmonella and F-specific RNA bacteriophage were enumerated in sludge and amended soil. Salmonella was not detected and only small numbers of bacteriophages were found in conventional, dewatered mesophilic anaerobically digested biosolids (DMAD). Neither organism was detected in soil. Escherichia coli numbers in soil increased with DMAD application compared with the unamended control, or soil receiving enhanced treated, thermally dried digested (TDD) and composted (CPT) biosolids. Empirical statistical models were developed summarizing the relationship between soil temperature, moisture content and time and E. coli populations. Background numbers of E. coli declined with increasing soil temperature and decreasing soil moisture responding to seasonal patterns in environmental conditions. Time following application was the only significant explanatory variable of E. coli numbers and decay in DMAD-amended soil.E. coli are an indigenous component of the microbial community in field soil and populations increased in cool, moist soil during autumn-winter and declined in warm, dryer soil during spring-summer. Enhanced treated biosolids were not a source of E. coli, but reduced the size of the indigenous population possibly by stimulating the activity of predatory and competing soil flora because of the organic substrate input from sludge. Conventionally treated biosolids increased E. coli numbers in soil. However, introduced bacteria declined rapidly and survival was limited to 3 months, irrespective of the timing of sludge application or environment.The results provide assurance that residual numbers of pathogens applied to soil in treated biosolids decay to background values well within cropping and harvesting restrictions imposed when sewage sludge is spread on farmland.

Oxide materials of desired stoichiometry are challenging to make in small quantities. Nanostructured thin films of multiple oxide materials were obtained by using pulsed laser deposition and multiple independent targets consisting of Si, BaTiO3, and B. Programmable stoichiometry of nanostructured thin films was achieved by synchronizing a 248-nm krypton fluoride excimer laser at an energy of 300 mJ/pulse, a galvanometer mirror system, and the three independent target materials with a background pressure of oxygen. Island growth occurred on a per pulse basis; some 500 pulses are required to deposit 1 nm of material. The number of pulses on each target was programmed with a high degree of precision. Trends in material properties were systematically identified by varying the stoichiometry of multiple nanostructured thin films and comparing the resulting properties measured using in situ spectroscopic ellipsometry, capacitance measurements including relative permittivity and loss, and energy dispersive spectroscopy (EDS). Films were deposited ∼150 to 907 nm thickness, and in situ ellipsometry data were modeled to calculate thickness n and k. A representative atomic force microscopy measurement was also collected. EDS, ellipsometry, and capacitance measurements were all performed on each of the samples, with one sample having a calculated permittivity greater than 20,000 at 1 kHz.

Introduction Emergency surgical patients account for around half of all NHS surgical workload and 80% of surgical deaths. Few trainees opt to CCT in General Surgery, and there is no recognised subspecialty training program in Emergency General Surgery (EGS). Despite this lack of training and relevant assessment by examination, there appears to be an increasing number of EGS posts advertised. This may be associated with a reduction in the numbers of breast or vascular surgery posts that have general surgical commitments. We sought to explore changes in consultant surgeon job adverts over time. Method All consultant surgeon posts, advertised in the British Medical Journal between January 2009 and December 2014 were included. Posts in 9non-general surgical9 specialties were excluded. Data collected included specialty, region and institute of advertised post. For the purposes of statistical analysis, data was divided into two separate year bands: 2009 – 2011 and 2012 – 2014. Statistical analysis was by Chi-squared test; p Results Over the six-year study period, there were 1240 consultant job adverts in a general surgical specialty. Nine hundred and seventy-five were substantive posts; the region with the most jobs was London and the South East (n = 278). The total number of posts was 645 in 2009–11 and 595 2012–14. The most common specialties advertised were colorectal (313), breast (248), upper GI (207), pure general surgery (170) and vascular (80). There were 55 jobs advertised in EGS, either with (20) or without (35) another subspecialty. The number of EGS adverts increased significantly in 2012–14 compared to 2009–11 (p = 0.008). London and the South East were the highest recruiters to EGS posts (10% of all consultant surgeon posts advertised in the region). There was a borderline decrease in the number of breast with general surgery posts advertised (p = 0.021). Numbers of vascular with general surgery jobs and purely general surgery jobs did not change significantly over time. Conclusion This data demonstrates increasing societal need for EGS consultants over the last six years and the emergence of Emergency Surgery as a new subspecialty. The current training system in EGS on an ‘ad hoc’ basis alongside subspecialty training, may not adequately prepare newly appointed consultants. This is confounded by shortened training times in pre-existing subspecialties and introduction of EWTD. In order to meet the EGS needs of the NHS, general surgical training and the examination system need to be revised. Disclosure of interest None Declared.

The European Landfill Directive requires the phased reduction of biodegradable waste disposal to landfill. One option, with significant potential to divert biodegradable municipal waste from landfill, is to encourage householders to compost their organic waste at home and this approach is supported in principle by the UK Government. However, whilst the benefits of home composting are recognized, there is uncertainty about the actual quantitative effectiveness of this approach to biodegradable waste management and, currently, Local Authorities responsible for municipal waste disposal and recycling do not receive credit or recognition for promoting this activity in the UK. This project aims to quantify the amounts of waste diverted from landfill through home composting, and other household waste recycling methods, by measuring the effects of these practices on the quantity and composition of residual waste produced at the individual household level. An automatic weighing system was fitted to a refuse collection vehicle (RCV) to provide data on the waste arisings from 324 households in the urban Borough of Runnymede, West London. The households were allocated into four groups according to the waste management practices: home composting; home composting + kerbside recycling, kerbside recycling only and a control group who did not compost or participate in the kerbside recycling scheme. The RCV weight data were complemented by a detailed compositional analysis of residual waste collected from the households. This paper presents a summary and overview of the key results and outputs from the research programme.

Layers of GaN deposited on Si substrates have been studied using Thermal Admittance Spectroscopy (TAS) and Optical Admittance Spectroscopy (OAS). Transparent front-side contacts were used to facilitate the optical measurements. Six specimens were cut from the same location in two different wafers, and three samples were randomly chosen from other growths. A shallow level at EC − 0.051 eV was found in all the specimens using TAS. In some specimens this peak was asymmetric, indicating more than one level near this energy. Deeper levels were also seen in the high-temperature portion of the spectra, but were poorly resolved in most specimens. Illuminating the specimen with UV light at 25 K resulted in the thermal position of the peak shifting to a lower temperature, and hence, the calculated energy, of the peak shifting lower. The amplitude of the peak also decreased. Transient OAS measurements revealed the interesting phenomenon of negative persistent photo conductance at room temperature in some of the specimens when the illumination photon energy was less than the bandgap. The negative response time was very short. At lower temperatures, below 100 K, the negative response diminished, but the response time was still short. At wavelengths above the bandgap energy, normal transient response was seen, with a longer time constant.

The transient photo response of 4H- and 6H-SiC specimens at various wavelengths has been studied using Optical Admittance Spectroscopy. Differences in the transient response were found for excitation and recombination for different specimens in both materials. The results indicate that optical excitation of charge carriers to the conduction band is a single transition, but recombination of free carriers from the conduction band is a process involving multiple transitions to the ground state mediated by deep centers in the material. Similarities in the persistent photoconductance after excitation from deep centers, and after excitation at above bandgap energies, suggest that carriers from the conduction band drop through deep centers on the way to the valence band.

Thermal admittance spectroscopy has been used to determine the ground-state energies of the boron impurity in 6H-SiC. The background doping, NA−ND, of the samples used in this study ranged from 3×1016 to 1×1018 cm−3. From electron spin resonance studies, it is known that boron substitutes for silicon in the silicon carbide lattice occupying three inequivalent sites. Using admittance spectroscopy the ground state energies of Ev+0.27 eV, Ev+0.31 eV, and Ev+0.38 eV were determined for the shallow boron acceptor in 6H-SiC. The free carrier concentration does not appear to be the only determining factor for which the boron acceptor level is observed.

Differentiation of embryonic stem (ES) cells generally occurs after formation of three-dimensional cell aggregates, known as embryoid bodies (EBs). This differentiation occurs following suspension culturing of EBs in media containing a high (25 mM) glucose concentration. Although high-glucose-containing media is used for maintenance and proliferation of ES cells, it has not been demonstrated whether this is a necessary requirement for EB development. To address this, we examined the growth and differentiation of EBs established in 0-mM, 5.5-mM (physiological), and 25-mM (high) glucose concentrations, through morphometric analysis and examination of gene and protein expression. The effect on EB development of supplementation with basic fibroblast growth factor (FGF2) was also studied. We report that the greatest rate of EB growth occurs in 5.5 mM glucose media. A morphological study of EBs over 104 days duration under glucose-containing conditions demonstrated the development of all three major embryonic cell types. The difference from normal human development was obvious in the lack of rostrocaudal control by the notochord. In the latest stages of development, the main tissue observed appeared to be cartilage and cells of a mesodermal lineage. We conclude that physiological glucose concentrations are suitable for the culturing of EBs, that the addition of FGF2 enhances the temporal expression of genes including POU5F1, nestin, FOXA2, ONECUT1, NEUROD1, PAX6, and insulin, and that EBs can be cultured in vitro for long periods, allowing for further examination of developmental processes.

Impurity conduction (or hopping conduction) has been observed in the more heavily n‐type 4H–SiC samples by both temperature dependent resistivity measurements and thermal admittance spectroscopy. The measured activation energies e3 for hopping were 4–5 meV and 2.3–3.0 meV, respectively. No evidence of hopping conduction was seen by either method in the sample where ND–NA

High-resolution surface fluxes over the global ocean are needed to evaluate coupled atmosphere–ocean models and weather forecasting models, provide surface forcing for ocean models, understand the regional and temporal variations of the exchange of heat between the atmosphere and ocean, and provide a large-scale context for field experiments. Under the auspices of the World Climate Research Programme (WCRP) Global Energy and Water Cycle Experiment (GEWEX) Radiation Panel, the SEAFLUX Project has been initiated to investigate producing a high-resolution satellite-based dataset of surface turbulent fluxes over the global oceans to complement the existing products for surface radiation fluxes and precipitation. The SEAFLUX Project includes the following elements: a library of in situ data, with collocated satellite data to be used in the evaluation and improvement of global flux products; organized intercom-parison projects, to evaluate and improve bulk flux models and determination from the satellite of the input parameters; and coordinated evaluation of the flux products in the context of applications, such as forcing ocean models and evaluation of coupled atmosphere–ocean models. The objective of this paper is to present an overview of the status of global ocean surface flux products, the methodology being used by SEAFLUX, and the prospects for improvement of satellite-derived flux products.

Argon ions (Ar+) were implanted into n-type 4H-SiC epitaxial layers at 600 °C. The energy of the ions was 160 keV and at a dose of 2 × 1016 cm−2. After post-implantation annealing at 1600 °C, Schottky diodes were fabricated on the ion implanted samples. Bulk n-type 4H-SiC samples were irradiated at room temperature with 1 MeV electrons at doses of 1 × 1016 to 5.1 × 1017 el/cm2. The current density of the beam was 0.91 μA/cm2. Deep Level Transient Spectroscopy (DLTS) was used to characterize the induced defects. DLTS studies of Ar+ implanted samples showed six defect levels at EC – 0.18 eV, EC – 0.23eV, EC – 0.31eV, EC – 0.38 eV, EC – 0.72 eV, and EC – 0.81 eV. Z1/Z2 defect is the dominant defect in the electron irradiated sample and anneals out completely after 10 minutes at 1000 °C. However, Z1/Z2 defect in Ar+ implanted samples was stable up to 1600 °C. It is suggested that the annealing behavior of Z1/Z2 depends on the source of its formation.

Optical admittance spectroscopy has been used to study defects in 4H–SiC; the vanadium donor level at EC‐1.73 eV has been identified. The optical admittance spectrum of 4H–SiC is similar to that of 6H–SiC, where the vanadium donor level is at EC‐1.59 eV. The band gaps of 6H–SiC and 4H–SiC were measured. The values of 3.10±0.03 eV for 6H–SiC and 3.41±0.03 eV for 4H–SiC are in reasonable agreement with reported values. Using the vanadium donor level in both 4H–SiC and 6H–SiC as a common reference, the band offsets for 6H–SiC/4H–SiC heterojunction are estimated to be ΔEC=0.14 eV and ΔEV=0.17 eV.

The slow buildup of photoconductance due to a peak centered at 1.13 eV below the conduction band in n‐type 6H–SiC samples has been studied using optical admittance spectroscopy. The background doping of the samples ranges from 3.2×1015 cm−3 to 2×1018 cm−3. The results indicate that the carriers responsible for the observed conductance are excited from defect levels that are energetically close. The photoconductance transients are completely described by a sum of two exponential expressions. The relevant parameters, α1,α2,Gmax(1), and Gmax(2), are determined as functions of temperatures. The background doping ND‐NA has no effect on the conductance buildup process, this indicates that the nitrogen donors play no role either in the formation of the defect or in the buildup process of the photoconductance.

OBJECTIVE: To compare the effects of a standard American diet, a traditional low-fat diet, and a low-fat diet containing the fat substitute olestra on risk factors for heart disease and diabetes. DESIGN: A 9-month, double-blind, randomized, parallel-arm, feeding study comparing three diets: (1) control (33% fat), (2) fat-reduced (FR; 25% fat), and (3) fat-substituted (FS) where olestra replaced 1/3 of dietary fat (33% lipid and 25% digestible fat). Subjects were allowed to adjust their total energy intake as desired, allowing weight to fluctuate. SUBJECTS: A total of 37 healthy, obese men (age 36.7±1.3 y; body mass index 30.8±0.4 kg/m2). MEASUREMENTS: Body weight and composition by dual-energy X-ray absorptiometry, blood pressure, serum lipids, lipoproteins, hemostatic factors, glucose, insulin, and leptin at baseline and every 3 months. RESULTS: The FS group lost 6.27 kg of body weight by 9 months vs 4.0 kg in the control and 1.79 kg in the FR groups. There was a significant diet main effect on cholesterol (P=0.002), low-density lipoprotein cholesterol (P=0.003), and triglycerides (P=0.01), all of which decreased in the FS group but not the other groups by 9 months. Apolipoprotein B (ApoB) increased in the FR and control groups but was unchanged in the FS group (diet main effect P=0.04). High-density lipoprotein (HDL) cholesterol increased in all groups over 9 months (time main effect P=0.0001). Time main effects were also observed for cholesterol, ApoA1, ApoB, Factor VII, diastolic blood pressure, and glucose. After adjustment for % fat loss at 9 months, the effects of diet on change in risk factors remained significant only for triglycerides. DISCUSSION: Consumption of a low-fat diet containing olestra for 9 months produced significant improvement in cardiovascular risk factors, an effect largely explained by weight loss. Long-term low-fat diet consumption with or without olestra does not decrease HDL cholesterol.

Measurements were made on 86 male bovine fetuses collected from abattoirs in the vicinity of Sydney, Australia. The fetal body length was used to calculate the approximate day of gestational age (DGA); most fetuses were between 60 and 150 DGA. The distances from the caudal pole of the kidney (metanephros) to, respectively, the tip of the scrotum, the distal end of the testis and the internal ring of the inguinal canal were measured, as well as the dimensions of the testis and gubernaculum testis. Distances of (1) testis to inguinal canal, (2) inguinal canal to scrotum, (3) testis to scrotum and (4) gubernaculum to scrotum were calculated from these measurements, which were made on both left and right sides. The total length of the gubernaculum testis increased during transabdominal passage and during transinguinal passage of the testis. Furthermore, the gubernaculum appeared to maintain the testis at a relatively fixed distance from the scrotum during transabdominal passage so that the inguinal canal appeared to move towards the testis. The greatest distance between the testis and the tip of the scrotum was found during the transinguinal passage of the testis and was 2.8 cm for the left testis and 2.3 cm for the right. When located within the scrotum, each testis was still 1.6-1.7 cm from the tip of the scrotum, so the distance to be traversed was only 0.6-1.2 cm. Following passage of the testis through the inguinal canal, the gubernaculum became shorter and its distal tip was displaced toward the distal end of the scrotum. Traction by the gubernaculum could account for the final transposition of the testis from the external inguinal ring to the scrotum. Other factors involved in displacement of the testis include differential growth patterns as well as increases in the dimensions of the testis itself.

Adiponectin is an insulin-sensitizing hormone whose blood concentration is reduced in obesity and type 2 diabetes. Administration of recombinant adiponectin in rodents increases glucose uptake and increases fat oxidation in muscle, reduces fatty acid uptake and hepatic glucose production in liver, and improves whole body insulin resistance. The exact receptor and signaling systems are unknown, however, recent studies suggest adiponectin activates AMPK, a putative master metabolic regulator. Thus, excitement surrounds the potential for adiponectin, or a homologue of adiponectin, as pharamacotherapy agents for patients suffering from the metabolic syndrome and more particularly for individuals with insulin resistance and type 2 diabetes.

Design Operation Process Microbiology Performance Enhancement Keywords: septic tanks; wastewater treatment

SofScale is a pre-scaling gel, containing disodium EDTA and sodium lauryl sulphate, which is claimed to soften calculus and therefore facilitate its removal. 31 subjects were treated in a double blind randomised placebo controlled split mouth study to evaluate this product. Test or placebo gels were applied to the lingual surfaces of the mandibular teeth for 4 min and the time taken to complete the removal of supragingival calculus recorded. The operator recorded on which side the calculus was considered easier to remove and the patient indicated how comfortable the scaling had been. The mean calculus index was 1.99 for the SofScale group and 1.97 for the placebo. The mean time taken to complete scaling was 5.31 min for both groups. Using the Student t-test, there were no statistically significant differences (p > 0.7) between either the calculus index or time taken to complete the scaling between the groups. The operator did not consider SofScale to facilitate calculus removal and patients did not find calculus removal more comfortable when SofScale had been used. There was no increased sensitivity in the SofScale group following scaling. The results of this study do not support the use of SofScale as an adjunct to scaling.

Microbial biomass development in the sand and schmutzdecke layer was determined in two full-scale slow sand filters, operated with and without a light excluding cover. A standard chloroform fumigation-extraction technique was adapted to routinely measure microbial biomass concentrations in the sand beds. Sand was sampled to a depth of 10 cm and schmutzdecke was also collected at the same random positions on the uncovered filter. Interstitial microbial biomass in the uncovered sand bed increased with time and decreased with sampling depth. There was a small accumulation of sand biomass with time in the covered filter, but no relationship was apparent between biomass concentration and depth in this filter. Schmutzdecke did not develop on the covered filter and was spatially highly variable in the uncovered condition compared to the consistent patterns observed in interstitial biomass production. It is speculated that microbial biomass in the sand of uncovered filters is largely related to carbon inputs from photosynthetic activity in the schmutzdecke and involves mechanisms that spatially distribute carbon substrate from the schmutzdecke to the sand. However, total organic carbon and dissolved organic carbon removals were similar in both filters suggesting that relatively small biomass populations in covered filters are sufficient to remove residual labile carbon during advanced water treatment and little further advantage to water purification and organic carbon removal is gained by the increased production of biomass in uncovered slow sand filter beds.

Aluminum (Al) and argon (Ar) ions were implanted into n-type 4H-SiC epitaxial layers at 600 °C. The energy of the ions was 160 keV at a dose of 2 × 1016 cm-2. After annealing at 1600 °C for 5–60 minutes, Schottky diodes were fabricated on the ion implanted samples. Deep Level Transient Spectroscopy (DLTS) was used to characterize ion implantation induced defects. A defect at EC-0.18 eV was observed in the Al+ implanted devices annealed for five and fifteen minutes. However, annealing for 30 minutes produced an additional deeper defect at EC -0.24 eV. This defect annealed out after a sixty minute anneal. DLTS studies of Ar+ implanted devices showed six defect levels at EC -0.18 eV, EC -0.23 eV, EC -0.31 eV, EC -0.38eV, EC -0.72 eV, and EC -0.81eV. These defects are attributed to intrinsic-related defects. It is suggested that “hot” implantation of Al+ inhibits the formation of intrinsic-related defects. While “hot” implantation of Ar+ into 4H-SiC does not reduce the concentration of the vacancies and interstitials.

We have examined specimens of high-resistivity, and semi-insulating, 4H-SiC before and after thermal annealing at 1600 °C, using Optical Admittance Spectroscopy. We have found enhanced ultraviolet response in most specimens. Enhanced activation of previously undetected V impurities has also been observed. Peaks believed to be attributable to complex V-related defects were greatly reduced by annealing. The annealing was in addition to a thermal oxidation at 1150 °C for 4 hours. The purpose of the oxidation was to remove surface-related deep levels known to be present in polished SiC. Transition metal impurities in these bulk specimens were quantified by SIMS. In specimens where Ti was not detected by SIMS, no further activation of Ti centers was detected by Optical Admittance Spectroscopy.

A broad peak was observed in commercially available single‐crystal 6H‐SiC material. The samples were nitrogen doped, n type with free carrier concentration (ND−NA) of 1.3×1018 cm−3 that was determined from capacitance‐voltage (C‐V) measurements. The defect concentration profile showed that the defect was spatially localized and had a maximum concentration of 2.5×1014 cm−3 at 570 A from the semiconductor‐metal interface. The activation energy varied with applied voltage from Ec−0.40 eV at VR=−7 V to Ec−0.54 eV at VR=−5 V. This can be explained qualitatively in terms of the Poole–Frenkel effect. The defect was removed by the growth and subsequent removal of an oxide layer. Therefore, we conclude that the defect was caused by residual damage from the polishing process.

Deep levels have been identified and characterized in undoped Si1−xGex alloys grown on silicon substrates by gas-source molecular beam epitaxy. Hole traps in the p-type layers have activation energies ranging from 0.029–0.45 eV and capture cross sections (σ∞ ranging from 10−9 to 10−20 cm2. Possible origins of these centers are discussed.

It has been hypothesized that myostatin, a newly identified member of the transforming growth factor-beta (TGF-beta) family of proteins, acts as a negative regulator of skeletal muscle growth. Because bed rest induced muscle atrophy results from a decreased rate of muscle protein synthesis, we hypothesized that circulating levels of myostatin would be increased following prolonged bed rest. Twelve men (age, 35.8 +/- 4.6 yr; height, 175.7 +/- 2.3 cm; weight, 74.8 +/- 3.5 kg; mean +/- SE) were confined to bed for 25 days at 6 degrees head-down tilt while receiving triiodothyronine (T3; 50 micrograms/day) to accelerate protein loss. Total lean body and appendicular skeletal muscle mass were determined by dual energy x-ray absorptiometry (DEXA) before and after the bed rest period. Plasma myostatin-immunoreactive protein was measured in blood samples obtained after an overnight fast 5 days prior to, and on the 25th day of bed rest. Lean body mass decreased an average 2.2 kg (p0.0001). Appendicular skeletal muscle accounted for a majority of the lean body mass loss. On day 25 of bed rest, plasma myostatin-immunoreactive protein was 12% higher (p = 0.01) than measured at baseline. These data support the idea that myostatin regulates muscle growth in humans and that it may be a novel target for interventions aiming to reduce space flight induced muscle atrophy.

A chalk-based antimicrobial dentifrice was developed and has undergone in vitro testing to determine antimicrobial efficacy by kill-time studies, and in vivo clinical studies to determine anti-plaque build-up properties. The antimicrobial efficacy of the formulation is attributable to the following components; sodium lauryl sulphate, sodium monofluorophosphate, flavouring oils, triclosan, and low water activity. In vitro kill-time testing showed the dentifrice to have good activity against organisms associated with plaque, showing at least 99% reductions in the numbers of each organism. In vivo clinical results showed the dentifrice to protect against the build-up of plaque when compared to water alone. These results demonstrate that this dentifrice is effective in controlling plaque, and can thus be expected to promote good oral hygiene.

CRH increases energy expenditure and decreases food intake in experimental animals. We proposed the hypothesis that peripheral administration of CRH might increase energy expenditure in human subjects. Four men and four women (age, 19-39 yr) were randomized to a double blind, cross-over trial to test the effect of human CRH (hCRH), ovine CRH (oCRH), and placebo on resting energy expenditure measured by indirect calorimetry. CRH was administered by primed continuous infusion at progressively increasing doses of 0.5, 1.0, and 2.0 microg/kg.h at 2-h intervals. hCRH increased resting energy expenditure by 13.9% at the end of the infusion. Respiratory quotient fell from 0.828 to 0.768 during the hCRH infusion compared with a fall from 0.836 to 0.807 during placebo infusion (P0.05). Fat oxidation increased by 55% compared with placebo at the highest dose of hCRH. Heart rate increased during hCRH to 10.7 bpm higher than placebo (P0.05). oCRH did not increase heart rate. oCRH also had no significant effect on respiratory quotient, and only a small effect on energy expenditure. During hCRH infusion, venous plasma epinephrine, norepinephrine, glycerol, and nonesterified fatty acid levels were not significantly different from those during placebo treatment. Peripheral CRH administration offers a novel strategy to increase energy expenditure.

It is likely that the bright lights of a deep sea submersible coming into position at a hydrothermal vent seriously disturbs the behavior of the life found there. It may be of interest to observe the 'normal' behavior or natural response to selected stimuli. A possible means of providing illumination that permits such observation is discussed.

The aim of this study was to investigate whether the use of a pre-brushing mouthwash (Plax) improved subjects' oral hygiene over a 2-week period. In a double-blind placebo controlled cross-over study, 33 adult subjects (mean age 35.3 years) used either Plax or a placebo mouthwash for 30 s prior to toothbrushing during a 2-week period. After a washout period of 4 weeks, the subjects used the other mouthwash in the same way. The modified plaque index of Quigley and Hein (QHI) was recorded for 16 teeth (16, 14, 13, 11, 21, 23, 24, 26, 36, 34, 33, 31, 41, 43, 44, 46) at each visit. The bleeding index (BI) was recorded at the beginning and end of the study. Results were analysed using a paired one-tailed t-test. Neither plax nor placebo mouthwashes reduced plaque scores significantly (p > 0.05) below baseline. There was no statistically significant difference between the mean BI at the beginning of the trial (0.42) and at the end (0.44). These results suggest that the routine use of Plax is not a useful adjunct to toothbrushing.