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Colorectal cancer (CRC) is the third most common cancer globally. CRC risk is increased by obesity, and by its lifestyle determinants notably physical inactivity and poor nutrition. Obesity results in increased inflammation and oxidative stress which cause genomic damage and contribute to mitochondrial dysregulation and CRC risk. The mitochondrial dysfunction associated with obesity includes abnormal mitochondrial size, morphology and reduced autophagy, mitochondrial biogenesis and expression of key mitochondrial regulators. Although there is strong evidence that increased adiposity increases CRC risk, evidence for the effects of intentional weight loss on CRC risk is much more limited. In model systems, energy depletion leads to enhanced mitochondrial integrity, capacity, function and biogenesis but the effects of obesity and weight loss on mitochondria in the human colon are not known. We are using weight loss following bariatric surgery to investigate the effects of altered adiposity on mitochondrial structure and function in human colonocytes. In summary, there is strong and consistent evidence in model systems and more limited evidence in human subjects that over-feeding and/or obesity result in mitochondrial dysfunction and that weight loss might mitigate or reverse some of these effects.
An explanation is provided for the disruptive instability in diverted tokamaks when the safety factor
at the 95 % poloidal flux surface,
, is driven below 2.0. The instability is a resistive kink counterpart to the current-driven ideal mode that traditionally explained the corresponding disruption in limited cross-sections (Shafranov, Sov. Phys. Tech. Phys., vol. 15, 1970, p. 175) when
, the safety factor at the outermost closed flux surface, lies just below a rational value
. Experimentally, external kink modes are observed in limiter configurations as the current in a tokamak is ramped up and
decreases through successive rational surfaces. For
, the instability is always encountered and is highly disruptive. However, diverted plasmas, in which
is formally infinite in the magnetohydrodynamic (MHD) model, have presented a longstanding difficulty since the theory would predict stability, yet, the disruptive limit occurs in practice when
, reaches 2. It is shown from numerical calculations that a resistive kink mode is linearly destabilized by the rapidly increasing resistivity at the plasma edge when
. The resistive kink behaves much like the ideal kink with predominantly kink or interchange parity and no real sign of a tearing component. However, the growth rates scale with a fractional power of the resistivity near the
surface. The results have a direct bearing on the conventional edge cutoff procedures used in most ideal MHD codes, as well as implications for ITER and for future reactor options.
Substantial healthcare resources are devoted to panic disorder (PD) and coronary heart disease (CHD); however, the association between these conditions remains controversial. Our objective was to conduct a systematic review of studies assessing the association between PD, related syndromes, and incident CHD.
Relevant studies were retrieved from Medline, EMBASE, SCOPUS and PsycINFO without restrictions from inception to January 2015 supplemented with hand-searching. We included studies that reported hazard ratios (HR) or sufficient data to calculate the risk ratio and 95% confidence interval (CI) which were pooled using a random-effects model. Studies utilizing self-reported CHD were ineligible. Twelve studies were included comprising 1 131 612 persons and 58 111 incident CHD cases.
PD was associated with the primary incident CHD endpoint [adjusted HR (aHR) 1.47, 95% CI 1.24–1.74, p < 0.00001] even after excluding angina (aHR 1.49, 95% CI 1.22–1.81, p < 0.00001). High to moderate quality evidence suggested an association with incident major adverse cardiac events (MACE; aHR 1.40, 95% CI 1.16–1.69, p = 0.0004) and myocardial infarction (aHR 1.36, 95% CI 1.12–1.66, p = 0.002). The risk for CHD was significant after excluding depression (aHR 1.64, 95% CI 1.45–1.85) and after depression adjustment (aHR 1.38, 95% CI 1.03–1.87). Age, sex, length of follow-up, socioeconomic status and diabetes were sources of heterogeneity in the primary endpoint.
Meta-analysis showed that PD was independently associated with incident CHD, myocardial infarction and MACE; however, reverse causality cannot be ruled out and there was evidence of heterogeneity.
The radiocarbon content of whole air provides a theoretically ideal and now observationally proven tracer for recently added fossil-fuel-derived CO2 in the atmosphere (Cff). Over large industrialized land areas, determination of Cff also constrains the change in CO2 due to uptake and release by the terrestrial biosphere. Here, we review the development of a Δ14CO2 measurement program and its implementation within the US portion of the NOAA Global Monitoring Division's air sampling network. The Δ14CO2 measurement repeatability is evaluated based on surveillance cylinders of whole air and equates to a Cff detection limit of <0.9 ppm from measurement uncertainties alone. We also attempt to quantify additional sources of uncertainty arising from non-fossil terms in the atmospheric 14CO2 budget and from uncertainties in the composition of “background” air against which Cff enhancements occur. As an example of how we apply the measurements, we present estimates of the boundary layer enhancements of Cff and Cbio using observations obtained from vertical airborne sampling profiles off of the northeastern US. We also present an updated time series of measurements from NOAA GMD's Niwot Ridge site at 3475 m asl in Colorado in order to characterize recent Δ14CO2 variability in the well-mixed free troposphere.
Although depression and mania are often assumed to be polar opposites, studies have shown that, in patients with bipolar disorder, they are weakly positively correlated and vary somewhat independently over time. Thus, when investigating relationships between specific psychological processes and specific symptoms (mania and depression), co-morbidity between the symptoms and changes over time must be taken into account.
A total of 253 bipolar disorder patients were assessed every 24 weeks for 18 months using the Hamilton Rating Scale for Depression (HAMD), the Bech–Rafaelsen Mania Assessment Scale (MAS), the Rosenberg Self-Esteem Questionnaire (RSEQ), the Dysfunctional Attitudes Scale (DAS), the Internal, Personal and Situational Attributions Questionnaire (IPSAQ) and the Personal Qualities Questionnaire (PQQ). We calculated multilevel models using the xtreg module of Stata 9.1, with psychological and clinical measures nested within each participant.
Mania and depression were weakly, yet significantly, associated; each was related to distinct psychological processes. Cross-sectionally, self-esteem showed the most robust associations with depression and mania: depression was associated with low positive and high negative self-esteem, and mania with high positive self-esteem. Depression was significantly associated with most of the other self-referential measures, whereas mania was weakly associated only with the externalizing bias of the IPSAQ and the achievement scale of the DAS. Prospectively, low self-esteem predicted future depression.
The associations between different self-referential thinking processes and different phases of bipolar disorder, and the presence of the negative self-concept in both depression and mania, have implications for therapeutic management, and also for future directions of research.
Experiments demonstrate the ~77× amplification of 0.5 to 3.5-ps pulses of seed light by interaction with Langmuir waves in a low density (1.2 × 1019 cm−3) plasma produced by a 1-ns, 230-J, 1054-nm pump beam with 1.2 × 1014 W/cm2 intensity. The waves are strongly damped (kλD = 0.38, Te = 244 eV) and grow over a ~ 1 mm length, similar to what is experienced by scattered light when it interacts with crossing beams as it exits an ignition target. The amplification reduces when the seed intensity increases above ~1 × 1011 W/cm2, indicating that saturation of the plasma waves on the electron kinetic time scale (<0.5 ps) limits the scatter to ~1% of the available pump energy. The observations are in agreement with 2D PIC simulations in this case.
Europa is a prime target for astrobiology and has been prioritized as the next target for a National Aeronautics and Space Administration flagship mission. It is important, therefore, that we advance our understanding of Europa, its ocean and physical environment as much as possible. Here, we describe observations of Europa obtained during its orbital eclipse by Jupiter using the Hubble Space Telescope. We obtained Advanced Camera for Surveys Solar Blind Channel far ultraviolet low-resolution spectra that show oxygen line emission both in and out of eclipse. We also used the Wide-Field and Planetary Camera-2 and searched for broad-band optical emission from fluorescence of the surface material, arising from the very high level of incident energetic particle radiation on ices and potentially organic substances. The high-energy particle radiation at the surface of Europa is extremely intense and is responsible for the production of a tenuous oxygen atmosphere and associated FUV line emission. Approximately 50% of the oxygen emission lasts at least a few hours into the eclipse. We discuss the detection limits of the optical emission, which allow us to estimate the fraction of incident energy reradiated at optical wavelengths, through electron-excited emission, Cherenkov radiation in the ice and fluorescent processes.
Thirty-one laboratories examined a total of 6169 meat samples, 1236 from abattoirs and 4933 from retail and other outlets. Campylobacter jejuni was isolated from 98 (1·6%). A higher isolation rate of 49/1236 (4·0%) was found among abattoir than among retail and other samples (49/4933–1·0%). Twenty-two of the laboratories looked for salmonella; although 94/4002 (2·3%) were positive, in only one sample of minced beef were campylobacter and salmonella found together. Isolation rates for salmonellae were 75/3576 (2·1%) from retail and 19/426 (4·5%) from abattoir samples.
Analysis of the results revealed that (1) the contamination rate of raw red meat by C. jejuni is, in general, very low; (2) when contaminated, numbers of organisms are generally also very low; (3) enrichment procedures were of some value; 41/98 (42%) isolates were detected by enrichment only, but, on the other hand 8 (8%) were direct plate positive/enrichment negative; (4) practice at looking for the organism and increased seasonal temperatures over the survey period did not result in a noticeable increase in isolations; (5) there was no apparent correlation between campylobacter and salmonella isolations.
The results of examinations of stools for Bacillus cereus among three unrelated groups of individuals are presented. The groups consisted of (1) healthy schoolchildren aged 6–11 years in a rural region of South Africa examined during each of the four seasons of the year; (2) 15 healthy volunteers comprising staff of a London microbiology laboratory and their families examined on each of 3 consecutive weeks; (3) 75 unrelated young children, 2 months to 5 years of age, in a second rural region of South Africa examined during a pilot study of 1 week's duration on the aetiology of rural gastroenteritis. The stools of the last group were submitted as being related to present or recent diarrhoea in the respective children.
In group 1, B. cereus isolation rates ranged from 24·3% at the autumn visit to 43% at the summer visit with a significantly higher rate of isolation in the summer than at other seasons of the year (P <0·05). B. cereus was isolated from 40% of group 2 volunteers on week 1, none on week 2 and 20% on week 3. The organism was detected in the 12 positive specimens at levels of approximately 102/g and constituted 2·5–30% of the total aerobic spore-forming bacillus population in the stools. In group 3, B. cereuswas recovered from 18·7% of the stool samples and was isolated consecutively with other pathogens (entcropathogenic Escherichia coli and rotavirus) on only five occasions. In groups 1 and 3, < 5% of the stools had ‘3+ ‘levels of B. cereus(> 10 colonies per direct plate culture).
B. cereus was readily isolated from all of 10 food samples, representative of the typical diet of the group 1 individuals, and was present in substantial numbers (104 to 5·5 × 106/g) in half of them.
The isolation results, supported by serotyping, indicated that carriage of B. cereusin stools is transient and its presence at any one time reflects solely its intake with foods.
Results are presented from a number of epidemiological studies using enzyme immunoassays (EIA) based on the purified anthrax toxin antigens, protective antigen, lethal factor and oedema factor. Studies on sera from a group of 62 human anthrax patients in Turkey and from cattle in Britain following two unrelated outbreaks of anthrax show that EIA using protective antigen can be a useful diagnostic aid and will detect subclinical infections in appropriate circumstances. A serological survey on wildlife in the Etosha National Park, Namibia, where anthrax is endemic, showed that naturally acquired anthrax-specific antibodies are rare in herbivores but common in carnivores; in carnivores, titres appear to reflect the prevalence of anthrax in their ranges. Problems, as yet unresolved, were encountered in studies on sera from pigs following an outbreak of anthrax on a farm in Wales.
Clinical details, including treatment, of the human and one of the bovine outbreaks are summarized and discussed in relation to the serological findings.
Escherichia coli O 27 H 7 was found in 16 stool samples submitted during a Caribbean cruise (Cruise Z) by 29 patients reporting with diarrhoea. A retrospective search revealed E. coli O 27 H 7 in 11 of 20 and 2 of 14 stool cultures from patients on two previous cruises (Y and X respectively) and in a culture from fresh cream (Cruise Y). The repeated occurrence of E. coli O 27 H 7 in the absence of any other apparent cause suggested that this serotype may have been responsible for the diarrhoea. The results of pathogenicity tests suggested that this strain elaborated heat-stable (ST) enterotoxin.
The possibility that food may have been the vector is discussed.
Serological typing was used as an epidemiological tool in the investigation of 524 outbreakes of Clostridium perfringens food poisoning in the United Kingdom and 37 outbreaks in other countries.
Five thousand five hundred and fifty-four (77%) of 7245 strains of C. perfringens association 561 outbreaks were typable with the 75 Food Hygiene Laboratory antisera; in 354 (63%) of these outbreaks were typable with the 75 Food Hygiene Laboratory antisera; in 354 (63%) of these outbreaks a specific serotype was established as being responsible for the outbreak.
An assessment is made of the ability of two additional sets of antisera, prepared against 34 American and 34 Japanese strains of C. perfringens, to increase the number of strains which can be typed. The extent of cross-reaction between the three sets of antisera was determined and the results are discussed in relation to the source and history of the type strains.
This work describes the feasibility of using a polymer-based tissue equivalent gel for measuring radiation doses in situ. The gel is based on the MAGIC formulation thereby enabling it to be manufactured under normal atmospheric conditions. Its composition has been altered to achieve a similar sensitivity to the more widely used, but technically more difficult to produce, PAG gels. Irradiation of the gel material causes polymerisation of the molecular structure resulting in a shortening of transverse relaxation time (T2), which can be imaged using Magnetic Resonance Imaging (MRI). This work calibrates the radiation response in terms of transverse relaxation rate (R2) and uses this information to provide absolute dose verification in a separate gel, which has been previously irradiated to a known configuration. Results demonstrate that this technique is able to verify radiation doses to within a few percent of delivered intent in three dimensions and with high spatial resolution. This work may be followed by anyone with an interest in the quality assurance of advanced conformal radiotherapy delivery methods.
To evaluate the impact of the 1998 Australian Measles Control Campaign on immunity to measles and rubella, 4400 opportunistically-collected sera, submitted to diagnostic laboratories across Australia from subjects aged 1–49 years, and 3000 from subjects aged 1–18-years, were tested before and after the campaign, respectively. The proportion of individuals aged 1–18 years who were immune to measles rose from 85% before, to 90% after, the campaign (P < 0·001). The greatest increase was in preschool (7%, P < 0·001) and primary school (10%, P < 0·001) children, who were actively targeted by the campaign. Rubella immunity in 1–18 year-olds rose from 83% to 91% (P < 0·001), again with significant increases in preschool (4%, P = 0·002) and primary school (16%, P < 0·001) children. 94% of individuals aged 19–49 years were immune to rubella. These serosurveys confirm other evidence of the effectiveness of the Australian Measles Control Campaign and demonstrate the value of serosurveillance using opportunistically collected sera.
Mitochondrial DNA (mtDNA) defects are responsible for symptom complexes that are characteristically heterogeneous but are typically represented by muscle weakness and neurological deficits. One common feature of mitochondrial disease is deafness. This report details the assessment and outcome of a patient with a previously undescribed mtDNA rearrangement who underwent cochlear implantation. The patient shows a marked improvement in sentence recognition tests and recognition of environmental sounds. Patients with profound sensorineural hearing loss due to mtDNA defects should be considered as candidates for cochlear implantation when they no longer benefit from conventional hearing aids.
In this chapter we present four models of parent–professional partnerships, including a discussion of the power relationships within each. The approaches that we discuss include 1) parent counseling/psychotherapy, 2) family involvement, 3) family-centered services, and 4) collective empowerment. The research and professional literature upon which we base our analysis is drawn from the early childhood special education field. That literature has been constructed primarily since the 1950s with a focus on young children with developmental disabilities. Family–professional partnership trends in other areas of early childhood services have differed from those that we are presenting; however, it is beyond the scope of a single chapter to analyze partnership models within all early childhood fields.
We begin the chapter with a discussion of the type of power – power-over, power-with, and power-through – that are generally inherent in each of the four family–professional partnership models. The models are further portrayed through the use of a what-might-have-been vignette. We begin the chapter with a vignette of an imaginary family, one that prototypically might be known to any service provider. As we discuss each of the models and the power relationships within those models, we suggest how that model may have been brought to bear on that family.
Jeanette A. is a 37-year-old African American woman who lives in a community of approximately 65,000 people in an eastern state. Her daughter, Tisha, was born at 26 weeks gestation, weighing 1 pound, 12 ounces.
There have been several proposals for the mechanism
by which we are able to recognize an object across a number
of viewpoints. Viewpoint-dependent accounts suggest that
recognition may be based on an incremental transformation
(e.g., mental rotation) strategy, while a variety of viewpoint-independent
mechanisms for object recognition have also been proposed.
Recent research in neurobiology, based on the two cortical
visual systems account, suggest that the processes of viewpoint-dependent
and viewpoint-independent object recognition may rely on
separate anatomical regions, and that brain lesions may
leave patients with selective access to particular types
of representation. Evidence from a variety of neuropsychological
disorders are reviewed to support the position that viewpoint-independent
object recognition depends upon the integrity of occipitotemporal
structures. In addition, it is suggested that viewpoint-dependent
processes (perhaps depending on occipitoparietal structures)
may supplement this primary system under nonoptimal circumstances.
(JINS, 1997, 3, 288–298.)
This paper describes the application of fine needle aspiration cytology (FNAC) performed on92 patients with salivary gland lesions in a Head and Neck Surgery Clinic. The aspirates were immediately reported by a cytopathologist and the reports conveyed to the surgeon during the same clinic visit. FNAC results were then compared with histology in those patients who underwent surgery and with the clinical course of the disease at subsequent clinic visits in patients where surgery was not performed. The cytological diagnosis was incorrect in five cases, one of which was a false negative result. There were no false positive results. The sensitivity was 90.9 per cent and the specificity 100 per cent. This rapid report system of fine needle aspiration cytology has been found to be safe, free of complications, and helpful in the planning of treatment.
A prospective study of 200 patients was conducted to evaluate the use of pulse oximetry as an adjunct to clinical monitoring of critically ill patients transported by rotary-wing aircraft with non-pressurized cabins. Thirty-four subjects (17%) were found to have significant hemoglobin desaturation of less than 90%, as defined by pulse oximetry (SpO2). Data were recorded continuously for later review. Desaturation often was noted prior to alterations in vital signs or clinical appearance. In 32 of the 34 hypoxemic subjects (94%), therapeutic interventions corrected the low SpO2. The use of pulse oximetry permitted measures for cardiorespiratory support to be instituted and assessed more rapidly than otherwise would have been possible. The availability of a continuous record of SpO2 facilitated detailed review of case management. It is concluded that the use of pulse oximetry is a practical and valuable adjunct for monitoring critically ill patients transported by rotary-wing aircraft.