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In this paper, class operators are used to give a complete listing of distinct base radical and semisimple classes for universal classes of finite associative rings. General relations between operators reveal that the maximum order of the semigroup formed is 46. In this setting, the homomorphically closed semisimple classes are precisely the hereditary radical classes and hence radical–semisimple classes, and the largest homomorphically closed subclass of a semisimple class is a radical–semisimple class.
Inflammation of the mammary gland following bacterial infection, commonly known as mastitis, affects all mammalian species. Although the aetiology and epidemiology of mastitis in the dairy cow are well described, the genetic factors mediating resistance to mammary gland infection are not well known, due in part to the difficulty in obtaining robust phenotypic information from sufficiently large numbers of individuals. To address this problem, an experimental mammary gland infection experiment was undertaken, using a Friesian-Jersey cross breed F2 herd. A total of 604 animals received an intramammary infusion of Streptococcus uberis in one gland, and the clinical response over 13 milkings was used for linkage mapping and genome-wide association analysis. A quantitative trait locus (QTL) was detected on bovine chromosome 11 for clinical mastitis status using micro-satellite and Affymetrix 10 K SNP markers, and then exome and genome sequence data used from the six F1 sires of the experimental animals to examine this region in more detail. A total of 485 sequence variants were typed in the QTL interval, and association mapping using these and an additional 37 986 genome-wide markers from the Illumina SNP50 bovine SNP panel revealed association with markers encompassing the interleukin-1 gene cluster locus. This study highlights a region on bovine chromosome 11, consistent with earlier studies, as conferring resistance to experimentally induced mammary gland infection, and newly prioritises the IL1 gene cluster for further analysis in genetic resistance to mastitis.
Pomegranate (Punica granatum), a polyphenol-rich fruit, has been suggested to reduce cardiovascular risk due to its antioxidant properties. Hypertension and obesity are the most preventable cardiovascular risk factors. Few studies on blood pressure and/or body-weight status have been conducted in human subjects. Previous investigations have tended to focus on pomegranate juice. The aim of the present study was to investigate the effect of pomegranate extract (PE) on blood pressure and anthropometric measures in adults with no symptomatic disease. A total of fifty-five participants enrolled in a randomised double-blinded placebo-controlled clinical trial where they were assigned to either PE capsules or placebo capsules for 8 weeks. Blood pressure, body weight, waist circumference, waist:hip ratio (WHR) and body composition (lean body mass, body fat) were measured at baseline, week 4 and week 8. Results showed a significant decrease in diastolic blood pressure after 8 weeks (by 2·79 (sd 5·32) mmHg; P < 0·05), while the decrease in systolic blood pressure did not reach statistical significance (2·57 (sd 7·4) mmHg; P > 0·05). Body fat percentage, lean body mass, waist circumference and WHR did not significantly differ between groups at the end of the intervention. Results suggest that PE may reduce blood pressure and possibly prevent hypertension in the normotensive population. Further large trials are required to elucidate this effect.
Cubic boron nitride (cBN) is a synthetic wide band gap material that has attracted attention due to its high thermal conductivity, optical transparency and optical emission. In this work, defects in cBN have been investigated using experimental and theoretical X-ray absorption near edge structure (XANES). Vacancy and O substitutional defects were considered, with O substituted at the N site (ON) to be the most energetically favorable. All defects produce unique signatures in either the B or N K-edges and can thus be identified using XANES. The calculations coupled with electron-irradiation / annealing experiments strongly suggest that ON is the dominant defect in irradiated cBN and remains after annealing. This defect is a likely source of optical emission in cBN.
Hexagonal boron nitride (hBN) is a promising material for a range of applications including deep-ultraviolet light emission. Despite extensive experimental studies, some fundamental aspects of hBN remain unknown, such as the type of stacking faults likely to be present and their influence on electronic properties. In this paper, different stacking configurations of hBN are investigated using CASTEP, a pseudopotential density functional theory code. AB-b stacking faults, in which B atoms are positioned directly on top of one another while N atoms are located above the center of BN hexagons, are shown to be likely in conventional AB stacked hBN. Bandstructure calculations predict a single direct bandgap structure that may be responsible for the discrepancies in bandgap type observed experimentally. Calculations of the near edge structure showed that different stackings of hBN are distinguishable using measurements of core-loss edges in X-ray absorption and electron energy loss spectroscopy. AB stacking was found to best reproduce features in the experimental B and N K-edges. The calculations also show that splitting of the 1s to π* peak in the B K-edge, recently observed experimentally, may be accounted for by the presence of AB-b stacking faults.
Following previous work on the anti-giardial effect of blueberry polyphenols, a range of polyphenol-rich extracts from berries and other fruits was screened for their ability to kill Giardia duodenalis, an intestinal parasite of humans. Polyphenol-rich extracts were prepared from berries using solid-phase extraction and applied to trophozoites of Giardia duodenalis grown in vitro. All berry extracts caused inhibition at 166 μg gallic acid equivalents (GAE)/ml phenol content but extracts from strawberry, arctic bramble, blackberry and cloudberry were as effective as the currently used drug, metronidazole, causing complete trophozoite mortality in vitro. Cloudberry extracts were found to be the most effective causing effectively complete trophozoite mortality at 66 μg GAE/ml. The polyphenol composition of the more effective berry extracts suggested that the presence of ellagitannins could be an important factor. However, the potency of cloudberry could be related to high ellagitannin content but also to the presence of substantial amounts of unconjugated p-coumaric acid and benzoic acid. These in vitro effects occur at concentrations easily achievable in the gut after berry ingestion and we discuss the likelihood that berry extracts could be effective anti-giardial agents in vivo.
Being an identical twin does not necessarily mean having identical perceptions of family functioning, nor of the twin relationship. Using the co-twin control design, the aim of this study was to explore perceptions of family dynamics and the twin relationship in monozygotic (MZ) twins discordant and concordant for Developmental Coordination Disorder (DCD). It was hypothesized that, as has been found in twins discordant for cerebral palsy, twins without DCD would perceive family functioning as less healthy than would their co-twins with DCD. It was also hypothesized that the twin relationship would be regarded generally as mutually supportive. Questionnaire data on 866 sets of MZ twins aged 6 to 17 years were used to identify seven sets discordant, and two sets concordant for DCD. Quantitative (General Functioning Scale of the Family Assessment Device — FAD), and qualitative (semi-structured interview) measures were used to assess family dynamics and the twin relationship. In discordant sets, six of seven twins without DCD rated family functioning at a less healthy level than did their co-twins with DCD. All twins in the DCD concordant sets rated their family functioning at a healthy level. From the semi-structured interviews, emergent themes included friendship, support, minimal sibling rivalry, and minor difficulties. It was concluded that, overall, the twin relationship was regarded as close and mutually supportive, with an ambivalent polarity between the best and most difficult aspects of being an identical twin. Implications for research, policy and clinical practice are discussed.
To better understand the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection in different patient populations, to perform quantitative analysis of MRSA in nasal cultures, and to characterize strains using molecular fingerprinting.
Prospective, multicenter study.
Eleven different inpatient and outpatient healthcare facilities.
MRSA-positive inpatients identified in an active surveillance program; inpatients and outpatients receiving hemodialysis; inpatients and outpatients with human immunodeficiency virus (HIV) infection; patients requiring cardiac surgery; and elderly patients requiring long-term care.
Nasal swab samples were obtained from January 23, 2006, through July 27, 2007; MRSA strains were quantified and characterized by molecular fingerprinting.
A total of 444 nares swab specimens yielded MRSA (geometric mean quantity, 794 CFU per swab; range, 3-15,000,000 CFU per swab). MRSA prevalence was 20% for elderly residents of long-term care facilities (25 of 125 residents), 16% for HIV-infected outpatients (78 of 494 outpatients), 15% for outpatients receiving hemodialysis (31 of 208 outpatients), 14% for inpatients receiving hemodialysis (86 of 623 inpatients), 3% for HIV-infected inpatients (5 of 161 inpatients), and 3% for inpatients requiring cardiac surgery (6 of 199 inpatients). The highest geometric mean quantity of MRSA was for inpatients requiring cardiac surgery (11,500 CFU per swab). An association was found between HIV infection and colonization with the USA300 or USA500 strain of MRSA (P ≤ .001). The Brazilian clone was found for the first time in the United States. Pulsed-field gel electrophoresis patterns for 11 isolates were not compatible with known USA types or clones.
Nasal swab specimens positive for MRSA had a geometric mean quantity of 794 CFU per swab, with great diversity in the quantity of MRSA at this anatomic site. Outpatient populations at high risk for MRSA carriage were elderly residents of long-term care facilities, HIV-infected outpatients, and outpatients receiving hemodialysis.
To describe rates of surgical site infection (SSI) after hip replacement and to use these data to provide a simple mechanism for identifying poorly performing hospitals that takes into account variations in sample size.
Prospective surveillance study.
A total of 125 acute care hospitals in England that participated in mandatory SSI surveillance from April 1, 2004 through March 31, 2005.
Patients who underwent total hip replacement (THR) or hip hemiarthroplasty (HH).
A standard data set was collected for all eligible operations at participating hospitals for a minimum of 3 months annually. Defined methods were used to identify SSIs that occurred during the inpatient stay. Data were checked for quality and accuracy, and funnel plots were constructed by plotting the incidence of SSI against the number of operations.
Data were collected on 16,765 THRs and 5,395 HHs. The cumulative SSI incidence rates were 1.26% for THR and 4.06% for HH; the incidence densities were 1.38 SSIs per 1,000 postoperative inpatient days for THR and 2.3 SSIs per 1,000 postoperative inpatient days for HH. The risk of infection associated with revision surgery was significantly higher than that associated with primary surgery (2.7% [95% confidence interval, 2.0%-3.5%] vs. 1.1% [95% confidence interval, 1.0%-1.2%];P = .003). Rates varied considerably among hospitals. Nineteen hospitals had rates above the 90th percentile. However, the use of funnel plots to adjust for the precision of estimated SSI rates identified 7 hospitals that warranted further investigation, including 2 with crude rates below the 90th percentile.
Funnel plots of rates of SSI after hip replacement provide a valuable method of presenting hospital performance data, clearly identifying hospitals with unusually high or low rates while adjusting for the precision of the estimated rate. This information can be used to target and support local interventions to reduce the risk of infection.
To delineate factors associated with the successful endovascular treatment of extracranial carotid dissections, the authors review their management of 13 cases.
The records of 12 patients with 13 dissections were assessed with reference to mechanism of dissection, preoperative symptoms, presence of a pseudoaneurysm, treatment success, and etiology of treatment failure. Patients were followed prospectively and included six men and six women, ranging in age from 27 to 62 years.
Angioplasty and stenting were performed successfully in 11 of 13 procedures (10 of 12 patients). Follow-up in these 10 patients demonstrated excellent patency through the stented segment in nine of the 11 treated vessels. Two patients, both of whom suffered their original dissection as a result of endarterectomy, required further angioplasty and stenting for stenosis outside the previously treated arterial segment. Regarding the treatment failures, a stent deployment device could not navigate a tortuous loop in one, while a microwire could not be advanced beyond a pseudoaneurysm in the second. Six patients had pseudoaneurysms, four of which were treated only with stenting across the dissected arterial segment. All pseudoaneurysms treated in this fashion resolved. No permanent complications occurred as a result of endovascular therapy.
Angioplasty and stenting can be performed safely to manage carotid dissection. A pseudoaneurysm or tortuous anatomy can preclude therapy although the former typically resolves if angioplasty and stenting are feasible. Dissections secondary to endarterectomy may be associated with a higher rate of restenosis after stenting and may require further treatment.
Nuclear magnetic resonance (NMR) micro-imaging techniques have been employed to study noninvasively the spatial distribution of mobile protons (1H) around the cotyledonary node of flax (Linum usitatissimum) plants of two differing growth morphologies. The gross anatomy of the tissues of the stem can be discerned as a result of differences in their mobile 1H contents. The technique produced excellent images of the complex changes in stem structure that occur at the point of origin of side shoots. Detailed structure within the xylem could be visualized and the presence of fibre bundles deduced as dark areas amongst tissues of higher 1H signal intensity.
As a result of the non-invasive and non-destructive nature of NMR-imaging, the images obtained have been compared to micrographs obtained by conventional histological techniques on the same plant tissue. In general, the two approaches produce comparable results, but the NMR images are influenced by the relaxation properties of the protons as well as their concentration. Paramagnetic species, such as Mn2+ ions, produce enhanced relaxation rates of protons in their vicinity and an apparent increase in proton density at short recycle times. Thus an NMR image can yield both chemical and structural information. Some of the advantages and disadvantages of this technique over conventional histological methods are discussed.
One hundred and twelve alcoholic patients treated by an intensive one-month residential programme were followed up for one year. As a group, they were socially disadvantaged and highly dependent on alcohol. Outcome of treatment was assessed at six months and one year following discharge by multiple measures which included assessments of drinking behaviour, measurements of social stability, neuroticism and self-esteem, and self-ratings of satisfaction with important aspects of day-to-day living. During the first six months following treatment, 37% were abstinent or drinking in controlled fashion; during the second six months, 53% achieved this status. Improvement in drinking status was positively related to improvements in all other outcome variables.
A brief account is given of the work done in these laboratories on swayback and a comparison is made with a similar disease occurring in Australia. The Australian disease is due to an uncomplicated Cu deficiency of soil and herbage, but it is shown that swayback in this country is due to neither a Cu deficiency of soil nor herbage but nevertheless the affected animals suffer from a Cu deficiency and respond to Cu medication.
It is shown that ewes with a low blood Cu in Derbyshire on being transferred to Cambridge rapidly attained a normal blood Cu.
Analyses of grass from widely separated swayback-affected areas showed that in no case was the Cu content low.
A short discussion is given of the possibility of lead being implicated in the causation of the disease, but it is concluded that lead plays only a secondary role.
In the discussion it is pointed out that there is much fluorspar in the affected area of Derbyshire.
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