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This paper examines the velocity distribution function and cyclotron resonance conditions for a beam of electrons moving in a magnetic field which gradually changes with time. A spatial gradient of magnetic field is known to result in an unstable horseshoe distribution of electrons. The field gradient in time adds additional effects due to an induced electric field. The resultant anisotropic velocity distribution function, which we call a Luvdisk distribution, has some distinctive properties when compared to the horseshoe. Fitting the cyclotron resonance condition circle shows that the frequency of the resultant emission is under the local cyclotron frequency. While the spatial gradient results in the emission coming almost perpendicularly to the field, the direction of the radiation under a time-changing field has more variability. The Luvdisk distribution also arises when the magnetic field has a gradient both in space and time. The beam can be unstable if those gradients are added or subtracted from each other (if the gradients are of equal or different sign), which occurs even when the total change of magnetic field is negative. While the frequency of the emission is related to the final magnetic field value, its direction is indicative of the field’s history which produced the instability.

New experimental results of fluid-mineral reactions at hydrothermal conditions relevant to life demonstrate that key redox reactions involving iron, sulfur, and hydrogen remain at disequilibrium at 100 °C, even in a heterogeneous system and thus are energetically favorable for microbial metabolism. Predictions from geochemical models utilizing the experimental results and specific to two contrasting case studies from the East Pacific Rise were statistically characterized and correlated to the energetics of redox reactions available for intra-chimney microbial populations. In general, predictions of available energy for autotrophic metabolism are largely similar between the mature and the nascent chimneys, although important differences still exist. Metabolic processes predicted by energetics exhibit the same trends observed in the field data for the mature chimney, but overestimate the diversity observed in the nascent chimney. Several combinations of redox reaction pairs are predicted to support mixed consortia, while some combinations appear to favor more versatile microbes capable of utilizing several reactions under rapidly changing environmental conditions within chimney walls. In addition, conditions favorable to elemental sulfur reduction and methanogenesis exhibit a negative control on the diversity of microbial populations within these chimney walls, whereas H₂S oxidation, elemental sulfur oxidation and the knallgas reaction are positively correlated with both abundance and diversity of micro-organisms. Coupling field observations of both microbial diversity and geochemical heterogeneity with lab-based experimental and theoretical modeling can facilitate translation of the observed genetic diversity into physiological diversity, thus enhancing understanding of linked phenomena of microbially induced biogeochemical transformations in complex heterogeneous systems.

The Bent Hill massive sulfide deposit and ODP Mound deposit in Middle Valley at the northernmost end of the Juan de Fuca Ridge are two of the largest modern seafloor hydrothermal deposits yet explored. Trace metal concentrations of sulfide minerals, determined by laser-ablation ICP-MS, were used in conjunction with mineral paragenetic studies and thermodynamic calculations to deduce the history of fluid-mineral reactions during sulfide deposition. Detailed analyses of the distribution of metals in sulfides indicate significant shifts in the physical and chemical conditions responsible for the trace element variability observed in these sulfide deposits. Trace elements (Mn, Co, Ni, As, Se, Ag, Cd, Sb, Pb, and Bi) analyzed in a representative suite of 10 thin sections from these deposits suggest differences in conditions and processes of hydrothermal alteration resulting in mass transfer of metals from the center of the deposits to the margins. Enrichments of some trace metals (Pb, Sb, Cd, Ag) in sphalerite at the margins of the deposits are best explained by dissolution/reprecipitation processes consistent with secondary remineralization. Results of reaction-path models clarify mechanisms of mass transfer during remineralization of sulfide deposits due to mixing of hydrothermal fluids with seawater. Model results are consistent with patterns of observed mineral paragenesis and help to identify conditions (pH, redox, temperature) that may be responsible for variations in trace metal concentrations in primary and secondary minerals. Differences in trace metal distributions throughout a single deposit and between nearby deposits at Middle Valley can be linked to the history of metal mobilization within this active hydrothermal system that may have broad implications for sulfide ore formation in other sedimented and unsedimented ridge systems.

Aims In order to aid the monitoring of the new Meningococcal serogroup C Conjugate (Men C) vaccine, the Yellow Card Scheme was extended to allow nurses for the first time to report any suspected adverse reactions associated with these vaccines. We have analysed the Yellow Cards received by the Committee on Safety of Medicines (CSM) Wales from nurses reporting a suspected reaction in association with these vaccines during the first 16 months of the programme. Methods CSM Wales receives Yellow Cards from healthcare professionals in Wales. Details of Yellow Cards reporting a suspected adverse reaction associated with Men C vaccines during the study period were extracted from the CSM Wales database and analysed according to health professional category [nurses, General Practitioners (GP), hospital doctors or pharmacists]. Results During the study period 534 117 doses of Men C vaccines were administered in Wales; in the same period CSM Wales received 1095 Yellow Cards containing 1952 suspected reactions. Nurses completed 529 [48.3%, 95% confidence interval (CI) 43.6, 53.1] Yellow Cards compared with 294 (26.8%, 95% CI 22.7, 30.8) from GPs, 262 (23.9%, 95% CI 20.1, 27.6) from hospital doctors and 10 (0.91%, 95% CI 0.43, 1.73) from others, which include hospital pharmacists, community pharmacists and health visitors. The proportion of Yellow Cards sent by nurses was significantly higher than those sent by GPs and hospital doctors. Ninety-five percent CIs for differences in proportions (CI diff prop) were (0.175, 0.254) and (0.204, 0.282), respectively. The majority (90.9%, 95% CI 88.7, 93.5) of the Yellow Cards from nurses reported suspected reactions children in over the age of 5 (95% CI diff prop 0.861, 0.917). The spectrum of suspected adverse drug reactions (ADRs) involved the skin and subcutaneous tissue, central nervous system, general reactions, and the gastrointestinal tract. Of the suspected reactions reported by nurses, GPs and hospital doctors, 13.4% (95% CI 10.5, 15.8), 12.9% (95% CI 9.6, 16.8) and 9.1% (95% CI 6.5, 11.8), respectively, were of serious reactions. Nurses reported 52.5% (95% CI 45.4, 60.6) of all the suspected serious reactions, which was statistically more significant than hospital doctors [χ2 = 5.864, degree of freedom (DF) = 1, P 0.05). Conclusions Nurses were the health professionals who provided the largest proportion of reports of suspected ADRs and almost half of all reports during the Men C vaccination campaign. Their reports contained an equal proportion of serious suspected ADRs and the reports were documented as completely as those from GPs and hospital doctors.

The variable clinical manifestations of cystic fibrosis (CF) suggest the influence of modifier genes. Genetic and environmental factors that determine whether an individual will develop associated complications are still being determined. It has been proposed that the gene for hemochromatosis, HFE, may be a modifier locus for CF disease phenotype. Recent research has suggested a relationship between mutations to the HFE gene and the development of meconium ileus (MI) and liver disease in CF. This study aims to expand our knowledge of the HFE mutations C282Y and H63D carrier rate in an Irish population of CF allele carriers. PCR restriction enzyme analysis was performed on blood samples from CF patients to identify the C282Y and H63D mutations. HFE status of CF allele carriers and CF patients (Delta F508) homozygotes with and without meconium ileus was determined. The carrier frequency for C282Y was 30.8% for the Delta F508 homozygote MI positive group, as compared to 12.5% for the non-Delta F508 MI positive group but did not reach statistical significance (p = 0.27). Interestingly, no Delta F508 homozygote patients were homozygous for the C282Y mutation.

The incidence of cystic fibrosis (CF) at birth in Ireland is 1/1461. Neonate CF genetic testing is not routinely performed in Ireland. Currently, screening is only carried out where there is clinical evidence or a family history to suggest disease. Here we report the frequencies of common CF mutations occurring in an Irish population composed of samples collected from western, mid-western and southern regions of Ireland. Rarer CF mutations were also identified in a selected number of CF patients. In addition, a number of polymorphisms were identified, some of which are reported to be functionally and phenotypically important.

In this study, reverse transcription-polymerase chain reaction (RT-PCR) was optimized to analyse the presence of DAZ, RBMY1, USP9Y, protamine-2, SRY and actin messenger RNA (mRNA) in testicular cells of men suffering from idiopathic azoospermia. All samples (n = 28), including five controls, showed normal expression of actin, SRY and USP9Y. Sperm was not recovered from eight patients after testicular biopsy. Of these, four patients showed altered mRNA levels for the fertility genes, DAZ, RBMY1 and protamine-2. One patient, who was previously shown to be azoospermia factor region (AZF)b deleted, lacked RBM mRNA and presented with reduced amplification of protamine-2 mRNA. This correlated with previous studies, which proposed that RBM expression is exclusive to AZFb and that the lack oftesticular RBMY1 mRNA results in suppressed spermatogenesis. Two patients were each lacking DAZ mRNA but did show expression of RBMY1 mRNA at a reduced level, suggesting that there might be residual spermatogenesis in the absence of DAZ expression. Protamine-2 mRNA was detected in one patient and was absent in the second patient. Finally, one patient lacked DAZ, RBMY1 and protamine-2 mRNA. The 19 remaining azoospermic patients presented with normal expression patterns for each of the fertility genes studied. This study demonstrates that the expression of spermatogenesis-specific genes varies in azoospermia. The study of the expression of such genes in a larger number of patients might be useful in characterizing and identifying subpopulations of azoospermic men.

Dewatering of sewage sludge is an essential and costly part of the wastewater treatment process. The presence of microbial extracellular polymer (ECP) is important for sludge flocculation, but ECP has also been shown to have a detrimental effect on the dewaterability of certain sludge types. This paper investigates the relationship between sludge dewaterability and the level of ECP present in a range of sludges obtained from 8 full-scale municipal treatment works in the UK. Sludge dewaterability was determined using the capillary suction time (CST) test, and a thermal extraction process followed by solvent precipitation was used for ECP extraction. The results indicate that for each type of sludge examined there appears to be an optimum level of ECP (raw sludge 20 mg ECP/g SS; activated sludge 35 mg ECP/g SS; digested sludge 10 mg ECP/g SS) at which the sludge should exhibit maximum dewaterability. The establishment of a trend between sludge dewaterability and the quantity of ECP present opens up the possibility of manipulating the level of microbial polymer present to aid sludge dewatering, and hence reduce plant operating costs.

The region of the Y chromosome most critical for male fertility is called the azoospermia factor (AZF) region and it is located within subintervals five and six on the long arm of the Y chromosome. Several genes, all residing here, contribute to spermatogenesis and deletions in these genes are thought to be pathogenetically involved in some cases of male infertility associated with azoospermia or oligozoospermia. The aim of this study was to establish the prevalence of microdeletions in the AZF region of the Y chromosome in an Irish male population undergoing fertility treatment. To do this, we applied and compared two independent polymerase chain reaction (PCR) based screening methods, namely, a PCR protocol using several sequence-tagged site (STS) primer sets and a recently published multiplex PCR Y chromosome screening protocol. A total of 78 patients, attending the IVF unit at University College Hospital, Galway, were included in this study. Of them, 56 suffered from idiopathic azoospermic/oligozoospermic infertility. The remaining 22 patients had various conditions, which may have contributed to their infertility. A total of 50 age-matched normospermic men were included as controls. Two microdeletions were found; one in the AZFa region and one in AZFb region. These deletions were observed among the truly idiopathic cases. Further analysis was performed to study the extent of the deletions and it was confirmed that each deletion encompassed the respective AZF region including the AZF candidate gene.

Gemcitabine is a new deoxycytidine analog that exhibits significant cytotoxicity against a variety of cultured murine and human tumor cells. The cytotoxic action of gemcitabine appears to be due to the inhibition of DNA synthesis by inhibition of ribonucleotide reductase and by competition with dCTP for incorporation into DNA. We have previously shown that gemcitabine, but not cytosine arabinoside (ara-C), has a broad spectrum of antitumor activity against 7 different types of murine solid tumors. The activity of gemcitabine was schedule dependent. To further characterize its activity, gemcitabine was tested against 12 human carcinoma xenografts. When given on an every 3 day x 4 schedule, the following percent inhibitions (at maximally tolerated doses [MTD]; MTD/2) in tumor growth were seen: MX-1 mammary (93%; 80%), CX-1 colon (92%; 82%), HC-1 colon (96%; 92%), GC3 colon (98%; 94%), VRC5 colon (99%; 100%), LX-1 lung (76%; 61%), CALU-6 lung (75%; 38%), NCI-H460 lung (45%; 46%), HS766T pancreatic (73%; not tested), PaCa-2 pancreatic (69%; 40%), PANC-1 pancreatic (70%; 60%), and BxPC-3 pancreatic (9%; 19%). In contrast, only the LX-1 lung carcinoma xenograft was responsive to ara-C treatment, which inhibited tumor growth by a marginal 62 percent. Thus, like its activity against murine solid tumors, gemcitabine has excellent antitumor activity against a broad spectrum of human solid tumors.

Background Femoroacetabular impingement (FAI) is common with an estimated prevalence of 10–15% among young active individuals. The natural history of the disorder is progression to early osteoarthritis. Hip arthroscopy is recommended if conservative treatments fail; however, outcomes are unclear, particularly in highly active populations. Aim To evaluate the functional and vocational outcome of hip arthroscopy, as part of an evidence-based rehabilitation hip pain pathway, for the treatment of FAI in an active military population. Methods All patients in the defence rehabilitation hip pain pathway, with a confirmed diagnosis of FAI who failed conservative treatment, were assessed prior to surgery and at 2, 6 and 12 months postsurgery. Outcome measures included the Visual Analogue Scale (VAS) for hip pain, Non-Arthritic Hip Score (NAHS) for function, and vocational assessments including functional activity assessment (FAA) and Joint Medical Employment Standard for military employability and deployability. Results 101 patients completed the study (mean age=33 years) (male:female:75:26) (Royal Navy/British Army/Royal Air Force: 13%/48%/39%). Outcomes demonstrated significant improvements with large effect size. Preoperative NAHS mean=62.9 (SD 16.4), 12-month postoperative NAHS mean=78.8 (18.3), mean improvement in NAHS=15.9 (95% CI 12.3 to 19.5, p

Papuloerythroderma of Ofuji (PEO) is an uncommon skin condition most commonly described in Japan. The aetiology of PEO is unknown and treatment may be difficult. There are several reports of an association between PEO and malignancy, most particularly with T-and B-cell lymphomas. We describe PEO complicated by acute myeloid leukaemia occurring in a 62-year-old man. This association has not been reported previously.

BACKGROUND 5-Fluorouracil (5-FU) activity for various carcinomas of adults has been enhanced through the synergistic effect of leucovorin. Few pediatric studies of 5-FU in pediatric patients have been previously reported. METHODS Fifty-eight patients were treated with a 4-hour infusion of leucovorin, 400 mg/m2, administered daily for 5 days every 3-4 weeks. 5-Fluorouracil was administered by bolus injection 1 hour into each leucovorin infusion. Eleven adolescent patients with colorectal carcinoma, Stage 3 or 4, were treated with therapeutic intent, and other patients with a variety of drug-resistant pediatric solid neoplasms received similar treatment. RESULTS Patients with measurable disease of colorectal carcinoma responded favorably to 5-FU/leucovorin. Stable disease activity was seen with other tumor types. Specifically, there were no objective responses in 12 patients with Ewing's Sarcoma or 11 with osteosarcoma. There were 4 deaths in this study from causes related to toxicity. Nonfatal grade 3/4 toxicities included mucositis, rash, myelosuppression, nausea, vomiting, diarrhea, and infection. CONCLUSION The authors do not plan further evaluation of 5-FU/leucovorin in additional pediatric patients with colon cancer or other heavily pretreated malignant solid tumors and are presently treating their patients with colon carcinoma with 5-FU/leucovorin/interferon-alpha 2a.

The European Economic Community's (EC) RACE program (Research and Development in Advanced Communications Technologies in Europe) started with a definition phase in 1986. The main effort of the first phase was aimed at customer access connections (CACs) and customer premises networks (CPNs), as well as identification of services that will use these high-speed networks. In the second phase, which began in 1992, RACE projects are focused on managing the high data rates generated by these networks and the need for high-capacity transport networks. The greater functionality required and the large number of multiuser applications operating simultaneously within and between organizations generates data rates, both intra- and intersite, on the order of tens of Gb/s. Such high data rates will spur the market for gigabit networks. At the start of the RACE program, some projects were devoted to integrating interactive and distributive services into one ATM-based electrical user network interface. The main motivation was the use of the same fiber for different services to the subscriber. The RACE projects demonstrate fiber-based broadband infrastructures for local access. >

Human spermatozoa readily undergo in vitro capacitation and the acrosome reaction when exposed to a single, brief, high-voltage electric pulse in a medium containing calcium. Using the fluorescent calcium indicator, Fura-2, the changes in the intracellular calcium concentration of human sperm following exposure to voltages in the range of 200-2000 V cm-1 were measured. The induction of the acrosome reaction by the electropermeabilization pulse was also monitored. In comparison, changes in calcium uptake during a standard capacitation procedure in which sperm samples were incubated for 7 h were analyzed. At hourly intervals, acrosome reaction induction and intracellular calcium uptake were measured. The results indicate that electropermeabilization rapidly and efficiently produces high populations of acrosome-reacted sperm and a corresponding and associated increase in the intracellular calcium concentration.

Equations developed by Powell-Tuck and Hennessy in 2003(1) allow an estimate of body mass index (BMI) to be determined from mid upper arm circumference (MUAC). These equations are widely used in clinical practice when an individual's BMI cannot be calculated from measured height and weight. Anecdotal reports also suggest that estimated BMI derived from these equations is being used along with height to estimate the weight of some individuals who cannot be weighed, which in turn is used to calculate nutritional requirements. Secondary analysis of data for individuals who participated in the National Diet and Nutrition Survey (aged 65 years or over) suggests that there is a substantial variability in BMI predicted from an individual MUAC(2). However there appears to be a lack of such data in younger adults. Therefore a pilot study aimed at assessing the accuracy of BMI estimated using the Powell-Tuck and Hennessy equations and the subsequent accuracy of estimated weight, within a younger healthy female adult population was undertaken. Subjects who volunteered had their age recorded, and actual height, weight and MUAC measured. From this data actual BMI, estimated BMI and estimated weight were calculated. The relationship between actual BMI and MUAC, actual BMI and estimated BMI were explored using pearsons correlation. The accuracy of estimated BMI with actual BMI and estimated weight with actual weight were determined using Bland-Altman limits of agreement. 29 subjects volunteered with a mean age of 26.1 years (standard deviation (SD) 10.2 years) and a mean actual BMI of 23.1 Kg/m2 (SD 4.3 Kg/m2). A strong positive (r=0.912), statistically significant (p

The resources of accident and emergency (A&E) departments are often required to treat patients who are not within the catchment population of the local health authority. An assessment of workload caused by this particular group was carried out over a 2-month period at Northampton General Hospital which serves a population of 318,000. Details were collected and analysed on the patients' reason for attendance, investigations and treatment.

Time dependent heat transfer has been investigated in a fin assembly comprising an array of fins attached to a supporting wall. Convective heat exchange from the supporting wail and thermal interactions between the wall and fins art considered. A new implementation of the boundary element method solution technique has been devised to investigate oscillatory heat transfer in a fin assembly and is extended to investigate fin assembly heat transfer that is of a general periodic nature.

A new implementation of the boundary element method solution technique has been devised to investigate time-dependent heat transfer. This new approach has been applied to the problem of oscillatory heat transfer in an isolated fin. A comparison of the results with an existing analytical solution indicates that the boundary element technique developed in this paper is very efficient. Results are obtained for an aluminium fin over a wide range of heat transfer coefficients, fin dimensions and amplitude and frequency of the base temperature oscillation of the fin.

New experimental results of fluid-mineral reactions at hydrothermal conditions relevant to life demonstrate that key redox reactions involving iron, sulfur, and hydrogen remain at disequilibrium at 100 °C, even in a heterogeneous system and thus are energetically favorable for microbial metabolism. Predictions from geochemical models utilizing the experimental results and specific to two contrasting case studies from the East Pacific Rise were statistically characterized and correlated to the energetics of redox reactions available for intra-chimney microbial populations. In general, predictions of available energy for autotrophic metabolism are largely similar between the mature and the nascent chimneys, although important differences still exist. Metabolic processes predicted by energetics exhibit the same trends observed in the field data for the mature chimney, but overestimate the diversity observed in the nascent chimney. Several combinations of redox reaction pairs are predicted to support mixed consortia, while some combinations appear to favor more versatile microbes capable of utilizing several reactions under rapidly changing environmental conditions within chimney walls. In addition, conditions favorable to elemental sulfur reduction and methanogenesis exhibit a negative control on the diversity of microbial populations within these chimney walls, whereas H₂S oxidation, elemental sulfur oxidation and the knallgas reaction are positively correlated with both abundance and diversity of micro-organisms. Coupling field observations of both microbial diversity and geochemical heterogeneity with lab-based experimental and theoretical modeling can facilitate translation of the observed genetic diversity into physiological diversity, thus enhancing understanding of linked phenomena of microbially induced biogeochemical transformations in complex heterogeneous systems.

Studies of the transient heat transfer within extended surfaces have so far considered the fins in isolation. The isolated fin model is not representative of the physical boundary conditions within an extended surface heat exchanger since it does not account for the thermal effects of the supporting interface. The aim of this study is to extend the work on transient heat transfer within finned surfaces by incorporating the supporting wall in the problem. A mathematical one-dimensional solution for harmonic oscillatory heat transfer in a fin assembly is derived. It is concluded that, unlike steady-state situations, the transient heat transfer in a fin assembly can only be found by considering both the wall and the fins simultaneously.

The ability of mature, freeze‐thawed bovine sperm to bind exogenous end‐labelled or oligo‐labelled λ Hind III DNA restriction fragments was examined. Following 30 min. incubation of bovine sperm with P32 end‐labelled λ Hind III DNA and five washes with medium, approximately 5.8 ng DNA were bound to 107 sperm. Agarose gel autoradiography revealed that all of the λ Hind III DNA bands were present following sperm washes except for the smaller 0.5 Kb and 0.125 Kb bands. Incubation of sperm with 3H oligo‐labelled λ Hind III DNA gave a much higher level of binding (138 ng/107 sperm) than that found with end‐labelled DNA. This binding was entirely eliminated by DNase I. The separation of live and dead sperm fractions on Percoll gradients revealed that more oligo‐labelled λ Hind III DNA was found to be associated with the dead sperm fraction (31.2 ng/107 sperm) rather than the live sperm fraction (2.7 ng/107 sperm). Analysis of supravital stained, light microscopic autoradiographs confirmed that oligo‐la...

This study was conducted to evaluate the effects of an electric pulse (electroporation/electropermeabilization) on the binding of foreign DNA molecules to porcine spermatozoa. We previously examined various parameters involved in the association of foreign DNA with sperm after a simple incubation procedure and now report the effects of electroporation on this association. Using end-labeled and random primer labeled lambda-HindIII DNA fragments (23-0.125 kb), it was demonstrated that the DNA fragments interacted with the sperm after electroporation. These samples were then centrifuged and washed extensively to establish if any of the labeled DNA was associated with the spermatozoa. It was determined that approximately 10(8) molecules of DNA were associated with 1.5 x 10(7) mL-1 motile spermatozoa after five medium washes. After each wash, samples were withdrawn for gel analysis and scintillation counting. Gel analysis followed by autoradiography revealed the distinctive band pattern of lambda-HindIII DNA associating with sperm. In situ visualization studies with biotin-labeled DNA revealed that approximately 75% of motile sperm carried DNA bound to the post-acrosomal region. However, the intensity of the binding varied. with some sperm being more strongly stained than others. Using [H-3]dCTP-labeled DNA followed by light microscope autoradiography. approximately 70% of the sperm were strongly stained in the post-acrosomal region. There was a 5-10% increase in the amount of DNA bound by sperm when the samples were electroporated.

The aim of this study was to determine the fate of foreign DNA molecules bound to porcine sperm that had been capacitated and acrosome reacted in vitro using calcium ionophore and then used in the in vitro fertilization of zona-free hamster ova and zona-intact pig ova. Fluoresceinated Pisum sativum agglutinin (PSA) labeling was used to differentiate between acrosome-intact and acrosome-reacted sperm. This revealed that up to 80% of the sperm treated with calcium ionophore were acrosome reacted. Up to 70% of these acrosome-reacted sperm were labeled with the foreign DNA at the post-acrosomal region. Following association of DNA with the acrosome-reacted sperm, insemination droplets were prepared and zona-free hamster oocytes or zona-intact pig oocytes were added. The gametes were allowed to interact and then fixed and stained to visualize decondensed sperm heads that had penetrated into the oocytes. The sperm were stained with streptavidin peroxidases to detect the biotinylated foreign DNA bound to the decondensed heads. These studies revealed that 54% of fertilized hamster and pig oocytes contained decondensed sperm that had retained the post-acrosomal pattern of bound foreign DNA. After incubation with DNA-associated sperm, the oocytes were washed and cultured for 15-17 h. After fixation, up to 30% of hamster oocytes and 10% of porcine oocytes were found to contain sperm pronuclei. However, using the streptavidin peroxidase detection system, it was not possible to determine if any of these pronuclei contained the foreign DNA.

The problem of plane stress crack growth in a rectangular linearly viscoelastic plate under a pair of equal and opposite forces applied to the crack surface is studied experimentally. A fatigue crack is generated at the end of a slot cut on the specimen. After application of two opposite forces to the specimen with a fatigue crack, the crack grows gradually. It is found that under sufficiently small load, the speed of crack growth decreases as time increases, and crack arrest occurs finally. However when the applied load is sufficiently large, the crack grows with increasing speed until a catastrophic failure of the specimen takes place. Between these two extreme cases, the crack grows with an oscillatory speed. A theory based on the models of an infinite plate and double cantilevers is proposed for the explanation of the behaviour of crack growth under various loads. Our experimental results check fairly well with theoretical predictions.

Pseudomonas putida utilizes the catBC operon for growth on benzoate as a sole carbon source. This operon is positively regulated by the CatR protein, which is encoded from a gene divergently oriented from the catBC operon. The catR gene encodes a 32.2-kilodalton polypeptide that binds to the catBC promoter region in the presence or absence of the inducer cis-cis-muconate, as shown by gel retardation studies. However, the inducer is required for transcriptional activation of the catBC operon. The catR promoter has been localized to a 385-base-pair fragment by using the broad-host-range promoter-probe vector pKT240. This fragment also contains the catBC promoter whose -35 site is separated by only 36 nucleotides from the predicted CatR translational start. Dot blot analysis suggests that CatR binding to this dual promoter-control region, in addition to inducing the catBC operon, may also regulate its own expression. Data from a computer homology search using the predicted amino acid sequence of CatR, deduced from the DNA sequence, showed CatR to be a member of a large class of procaryotic regulatory proteins designated the LysR family. Striking homology was seen between CatR and a putative regulatory protein, TfdS.

In developing and implementing appropriate food risk management strategies, it is important to understand how consumers evaluate the quality of food risk management practices. The aim of this study is to model the underlying psychological factors influencing consumer evaluations of food risk management quality using structural equation modeling techniques (SEM), and to examine the extent to which the influence of these factors is country-specific (comparing respondents from Denmark, Germany, Greece, Slovenia, and the United Kingdom). A survey was developed to model the factors that drive consumer evaluations of food risk management practices and their relative importance (n= 2,533 total respondents). The measurement scales included in the structural model were configurally and metrically invariant across countries. Results show that some factors appear to drive perceptions of effective food risk management in all the countries studied, such as proactive consumer protection, which was positively related to consumers' evaluation of food risk management quality, while opaque and reactive risk management was negatively related to perceived food risk management quality. Other factors appeared to apply only in certain countries. For example, skepticism in risk assessment and communication practices was negatively related to food risk management quality, particularly so in the UK. Expertise of food risk managers appeared to be a key factor in consumers' evaluation of food risk management quality in some countries. However, trust in the honesty of food risk managers did not have a significant effect on food risk management quality. From the results, policy implications for food risk management are discussed and important directions for future research are identified.

This tenth best practice review examines four series of common primary care questions in laboratory medicine: (i) antenatal testing in pregnant women; (ii) estimated glomerular filtration rate calculation; (iii) safety testing for methotrexate; and (iv) blood glucose measurement in diabetes. The review is presented in question-answer format, referenced for each question series. The recommendations represent a precis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by Medline Embase searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus rather than evidence-based. They will be updated periodically to take account of new information.

This study developed quantitative real-time PCR assays for the DAZ and RBMY1 genes to determine the copy number of RNA extracted from testicular biopsies from a cohort of normospermic controls (n=6) and azoospermic males (n=17) including two males with Y-chromosome microdeletions (AZFc and AZFb + c). All patients underwent testicular sperm extraction (TESE) for intracytoplasmic sperm injection (ICSI). Forty percent of the azoospermic cohort showed a significant reduction in the copies of at least one of the genes (DAZ P=0.003; RBMY1 P=0.009). The histopathology of these patients ranged from Sertoli cell only (SCO) to severe hypospermatogenesis with interstitial fibrosis. The patient with the AZFb + c deletion lacked expression of DAZ and RBMY1 and had a histopathology of SCO. The patient with the AZFc deletion had reduced expression of RBMY1 and no DAZ expression with a histopathology of spermatocyte arrest. The quantitative real-time PCR assays for DAZ and RBMY1 gave positive predictive values of 78% and 70%, respectively for the recovery of sperm from testicular biopsy.

A continuous culture bioreactor was developed to enrich for nitrate and sulfate reducing thermophiles under in situ deep-sea pressures. The ultimate objective of this experimental design was to be able to study microbial activities at chemical and physical conditions relevant to seafloor hydrothermal vents. Sulfide, sulfate and oxide minerals from sampled seafloor vent-chimney structures [East Pacific Rise (9 degrees 46'N)] served as source mineral and microbial inoculum for enrichment culturing using nitrate and sulfate-enriched media at 70 and 90 degrees C and 250 bars. Changes in microbial diversity during the continuous reaction flow were monitored using denaturing gradient gel electrophoresis (DGGE) of PCR amplified 16S rRNA gene fragments. Time series changes in fluid chemistry were also monitored throughout the experiment to assess the feedback between mineral-fluid reaction and metabolic processes. Data indicate a shift from the dominance of epsilon Proteobacteria in the initial inoculum to the several Aquificales-like phylotypes in nitrate-reducing enrichment media and Thermodesulfobacteriales in the sulfate-reducing enrichment media. Methanogens were detected in the original sulfide sample and grew in selected sulfate-enriched experiments. Microbial interactions with anhydrite and pyrrhotite in the chimney material resulted in measurable changes in fluid chemistry despite a fluid residence time only 75 min in the reactor. Changes in temperature rather than source material resulted in greater differences in microbial enrichments and mediated geochemical reactions.

The androgen receptor (AR) gene, located on the X chromosome, is an important regulator of human spermatogenesis. In the past decade, the link between the CAG polyglutamine tract, situated on exon one of the AR gene, and reduced spermatogenesis has become a controversial one. Alterations in the length of the CAG polyglutamine tract have been associated with prostate cancer at a reduced intrinsic length and neuromuscular diseases at a CAG repeat length ofor = 40. Minimal intermediate increases have been linked with depressed spermatogenesis in infertile males. Asian and Australian groups have published an association between increased CAG repeat length and reduced spermatogenesis while many European studies have found no such association. The aim of this study was to document the association between increased CAG repeat length and reduced spermatogenesis in a group of Irish infertile males and controls known to have fathered at least one child. The study employed the ABI 377 DNA sequencer to size the CAG repeat region of exon one of the AR gene in each group. Statistical analysis revealed no actual link between the length of the CAG tract and a reduction of spermatogenesis in a cohort of infertile patients (n = 66) of Irish ethnic origin when compared to a fertile control group (n = 77) (p = 0.599).

Papuloerythroderma of Ofuji (PEO) is an uncommon skin condition most commonly described in Japan. The aetiology of PEO is unknown and treatment may be difficult. There are several reports of an association between PEO and malignancy, most particularly with T-and B-cell lymphomas. We describe PEO complicated by acute myeloid leukaemia occurring in a 62-year-old man. This association has not been reported previously.

A description is given of an evaluation of signature analysis techniques for online inspection of every compressor pump assembly from an automatic manufacturing and assembly line. Time-domain and frequency-domain diagnostic methods are tested for the ability to amplify the signal from a flaw in the presence of background signals. A signature analysis method is then developed for which the signals are only evaluated in the time domain. The torque signal must stay within a maximum and minimum pass band to be acceptable. The accelerometer signal is averaged to reduce random-noise signals, then squared and integrated. This is shown to provide a superior method for the detection of transient defects and the angular location of flaws. >