To determine whether structural abnormalities of the lamina cribrosa explain the presence of optic disc hemorrhages, we determined the spatial concordance between disc hemorrhages and laminar ...disinsertions from the sclera.
Prospective noninterventional study.
From open-angle glaucoma patients followed up prospectively, we identified 52 eyes of 46 open-angle glaucoma patients with optic disc hemorrhage (ODH+ group) in at least 1 optic disc photograph during follow-up. We also identified 52 control eyes of 46 glaucoma patients in whom no disc hemorrhage was detected (ODH- group).
Enhanced depth imaging optical coherence tomography of the optic nerve head (24 radial scans) was performed. The scans were de-identified and a trained observer masked to all clinical information determined the presence of laminar disinsertions in each of the 48 positions with a confidence score of 1 (least certain) to 5 (most certain). Only disinsertions with a score of 3 or more were included in the analysis.
Frequency and spatial concordance between disc hemorrhages and laminar disinsertions.
The median age, visual field mean deviation, and follow-up period of the ODH+ and ODH- groups was 77.5 and 70.8 years, -5.20 and -4.70 dB, and 10.4 and 9.9 years, respectively. There were 84 hemorrhages recorded in the ODH+ group. There were laminar disinsertions in 50 eyes (96%) in the ODH+ group and in 27 eyes (52%) in the ODH- group, with 2 or more disinsertions in 30 eyes (58%) and 5 eyes (10%), respectively. Most hemorrhages and disinsertions were located in the inferotemporal and superotemporal sectors. However, in individual patients, only 33 of the ODHs (39%) were located within a laminar disinsertion.
Laminar disinsertions occurred twice as frequently in eyes with ODHs; however, in individual patients, the spatial concordance between ODHs and laminar disinsertions was poor.
In this contribution we present platinum-group element (PGE) abundance and Os isotope data of North Atlantic Craton peridotite xenoliths (
n
=
62) sampled from four major clusters of ...kimberlite/ultramafic lamprophyre volcanism in W. Greenland. In addition, we analysed olivine separates from selected peridotites.
We find distinct differences in peridotites sampled from the northern (including the reworked Archean Nagssuqtoqidian mobile belt) and southern portions of the W. Greenland fragment of the NAC (WG-NAC). The heavily serpentinized harzburgitic to dunitic peridotites from the northern WG-NAC are typically marked by Os and Ir abundances that are somewhat lower than those of primitive mantle. Pt and Pd abundances are significantly depleted resulting in chondrite-normalized PGE patterns consistent with extensive melt extraction. As a consequence of the melting process, removal of sulphide and possibly a portion of residual PGE-rich alloys is likely. Typically, Os isotopes of these northern samples are unradiogenic (γOs
=
−
14.2 to −
6.6, average ca.−9.2), with separated olivines being similar in composition. The unradiogenic Os isotope compositions of the northern peridotites result in T
RD
erupt model ages clustering between 2.7 and 3.2 and also at ca. 2.0
Gyr. The grouping of the T
RD
erupt model ages correspond well with the U–Pb zircon ages derived from the trondjemite–tonalite–granodiorite continental crust (∼
2.8
Gyr) and the tectonic activity associated with the amalgamation and rifting of the WG-NAC and adjacent crust to the WG-NAC (Kangâmiut dykes
∼
2.0
Gyr; Nagssuqtoqidian ∼
1.8
Gyr). In detail however, a lack of Eoarchean Re depletion ages has to be recognized in this mantle root although the WG-NAC continental crust clearly preserves magmatic activity from the first 500
Ma of Earth's evolution. This lack of Eoarchean ages in the deep lithosphere may be due to unfortunate bias in the kimberlite eruption sites. Subordinate post-Archean melt extraction and metasomatic enrichment at ca. 2.0
Gyr is evident from the PGE and Os isotope systematics of some of these peridotites and is consistent with prolonged and episodic lithosphere evolution.
The southern WG-NAC peridotites appear to lack the extreme Pd depletion that is endemic in their northern counterparts. Generally the Os isotopes in these samples are more radiogenic (γOs
=
−
11.5 to +
1.1, average ca. −
7.2) and show a very strong mode of 2.0
Gyr T
RD
erupt model ages. Only a small number of Archean T
RD
erupt model ages can be recognized in this sub-suite of the WG-NAC lithosphere. Despite their relatively depleted major element characteristics, the PGE systematics of the southern peridotites do not preserve evidence of mantle melting and Pd enrichment is evident in a number of samples. Olivine separates from selected southern peridotites typically yield older, Archean, T
RD
erupt model ages relative to the corresponding whole-rock peridotites, although Pd enrichment is evident in the olivine PGE patterns.
The majority of WG-NAC peridotite xenoliths with 2.7 to 3.1
Gyr and 2.0
Gyr T
RD
erupt model depletion ages have normal FeO abundances that are consistent with shallow mantle melting. A significant subset of peridotite xenoliths are enriched in FeO and have 2.3–2.6
Gyr T
RD
erupt model ages that do not align with specific, well-characterized magmatic events, although granulite-facies metamorphism has been proposed during this period. Pronounced PGE over-printing via metasomatism appears to have affected this set of peridotites.
Overall it is apparent that the WG-NAC mantle xenoliths record lithosphere stabilization at the Meso-Neoarchean boundary which was followed by selective modification that has altered and overprinted Os isotope, PGE systematics and FeO abundances in some parts of the lithosphere
► Formation of Archean subcontinental lithospheric mantle. ► Diamond potential in Greenland. ► Platinum group element fractionation.
This paper provides a key element for the calculation of the damage costs of air pollution, namely the valuation of mortality, important because premature mortality makes by far the largest ...contribution. Whereas several studies have tried to quantify the cost of air pollution mortality by multiplying a number of deaths by the ‘value of prevented fatality’ (also known as ‘value of statistical life’), we explain why such an approach is not correct and why one needs to evaluate the change in life expectancy due to air pollution. Therefore, an estimate for the monetary value of a life year (VOLY) is needed. The most appropriate method for determining VOLY is contingent valuation (CV). To determine VOLY for the EU, we have conducted a CV survey in 9 European countries: France, Spain, UK, Denmark, Germany, Switzerland, Czech Republic, Hungary, and Poland with a total sample size of 1463 persons. Based on the results from this 9-country CV survey we recommend a VOLY estimate of 40,000 € for cost–benefit analysis of air pollution policies for the European Union. As for confidence intervals, we argue that VOLY is at least 25,000 € and at the most 100,000 €.
Sudden stops are the simultaneous occurrence of a currency/balance of payments crisis with a reversal in capital flows. We investigate whether sudden-stop crises are a unique phenomenon and whether ...they entail an especially large and abrupt pattern of output collapse (a “Mexican wave”). Using a panel data set over 1975–1997 and covering 24 emerging-market economies, we distinguish between the output effects of currency crises, capital inflow reversals, and sudden-stop crises. Sudden-stop crises have a large negative, but short-lived, impact on output growth over and above that found with currency crises. A currency crisis typically reduces output by about 2–3%, while a sudden stop reduces output by an additional 6–8% in the year of the crisis. The cumulative output loss of a sudden stop is even larger, around 13–15% over a 3-year period. Our model estimates correspond closely to the output dynamics of the ‘Mexican wave’ (such as seen in Mexico in 1995, Turkey in 1994 and elsewhere), and out-of-sample predictions of the model explain well the sudden (and seemingly unexpected) collapse in output associated with the 1997–1998 Asian Crisis.
Properties of the statpac visual field index Artes, Paul H; O'Leary, Neil; Hutchison, Donna M ...
Investigative ophthalmology & visual science,
2011-Jun-08, Letnik:
52, Številka:
7
Journal Article
Recenzirano
Odprti dostop
Purpose. To compare the properties of the visual field index (VFI) to those of mean deviation (MD) in patients with glaucoma. Methods. MD and VFI were calculated in data obtained from an ongoing ...longitudinal study in which patients with glaucoma (N = 109, 204 eyes) were observed for 9.8 years (median, 21 tests) with static automated perimetry. MD and VFI were compared in one test of each eye, and a subset of 30 tests were selected to compare the VFI with the judgments of eight experts who judged the percentage of the remaining visual field. In series of tests obtained over time, rates of change, statistical significance, evidence of nonlinearity, and variability were compared between both indices. Results. In single tests, MD and VFI were closely related (r = 0.88, P < 0.001). The relationship between both indices appeared linear, except in visual fields with MDs better than -5.0 dB where 29 (22%) of 129 eyes exhibited a ceiling effect (VFI = 100%). Based on this relationship, the predicted VFIs for visual fields with MDs of -5, -10, and -15 dB were 91%, 76%, and 60%, respectively. The percentage of remaining visual field suggested by the VFI exceeded the range of the experts' subjective judgments in 16 (53%) of 30 eyes. In series of tests obtained over time, rates of change with the two indices were closely related (r = 0.79, P < 0.001), and statistically significant reductions over time (P < 0.05) occurred in a similar number of eyes (92 45% with MD, and 87 43% with VFI). Of the 105 eyes with statistically significant (P < 0.05) negative trend in either MD or VFI, 74 (70%) showed such trends with both indices (κ = 0.69). The variability of MD and VFI increased with damage, and there was no evidence that change over time was more linear with VFI than with MD. Conclusions. The VFI provides a simple and understandable metric of visual field damage, but its estimates of remaining visual field were more optimistic than those of the experts. Rates of change over time with both indices were closely related, but the reliance of the VFI on pattern deviation probability maps caused a ceiling effect that may have reduced its sensitivity to change in eyes with early damage. In this group of patients there was no evidence to suggest that the VFI is either superior or inferior to the MD as a summary measure of visual field damage.
Weight-related attitudes refer to negative attitudes toward individuals because they are overweight or obese. These attitudes are widespread among children and adults and have been proven to be ...recalcitrant to intervention. To develop more effective interventions, it is necessary to understand the origin and development of explicit and implicit weight-related attitudes. In the present study, we administered two measures of explicit weight-related attitudes and an adaptation of an established social cognitive measure (Implicit Association Test) to 84 children (4- to 7-year-olds). Three main findings emerged. First, the two measures of explicit weight-related attitudes were significantly correlated, suggesting they may be tapping into a similar underlying construct. Second, implicit weight-related attitudes tended to higher in older children. Third, explicit and implicit weight-related attitudes were not related to each other. Implications for interventions to reduce weight-related attitudes are discussed.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The aims of this study were (i) to determine the prevalence and numbers of campylobacters in 63 samples of raw livers purchased at retail across the UK and (ii) to investigate whether the freezing of ...chicken livers contaminated with Campylobacter was a reliable method for decontamination. Chicken livers naturally contaminated with campylobacters were subjected to freezing at −15 and −25°C for one day and 7 days. Numbers of campylobacters on the livers were determined immediately before and after a 24‐h or 7‐days freeze treatment and daily during 3 days post‐thaw refrigerated storage. Freezing for 24 h at −25°C can reduce numbers of Campylobacter by up to 2 log10 CFU g−1. Freezing the livers for 24 h at −25°C, thawing overnight in a fridge set to 4°C and refreezing for another 24 h at −25°C reduced the numbers of campylobacters by up to three logs. Reduction in the numbers of campylobacters was significantly greater following a second freeze treatment compared with a single freeze treatment.
Significance and Impact of the Study
Freezing chicken livers can reduce, but not eliminate, campylobacters. If poultry processors were to freeze livers destined for human consumption as part of routine processing, there is a potential for a reduction in campylobacteriosis associated with the consumption of imperfectly cooked chicken livers and derivatives, such as pâté.
Significance and Impact of the Study: Freezing chicken livers can reduce, but not eliminate, campylobacters. If poultry processors were to freeze livers destined for human consumption as part of routine processing, there is a potential for a reduction in campylobacteriosis associated with the consumption of imperfectly cooked chicken livers and derivatives, such as pâté.
Complex I (NADH:ubiquinone oxidoreductase) is the first and largest multimeric complex of the mitochondrial respiratory chain. Human complex I comprises seven subunits encoded by mitochondrial DNA ...and 38 nuclear-encoded subunits that are assembled together in a process that is only partially understood. To date, mutations causing complex I deficiency have been described in all 14 core subunits, five supernumerary subunits, and four assembly factors. We describe complex I deficiency caused by mutation of the putative complex I assembly factor C20orf7. A candidate region for a lethal neonatal form of complex I deficiency was identified by homozygosity mapping of an Egyptian family with one affected child and two affected pregnancies predicted by enzyme-based prenatal diagnosis. The region was confirmed by microcell-mediated chromosome transfer, and 11 candidate genes encoding potential mitochondrial proteins were sequenced. A homozygous missense mutation in
C20orf7 segregated with disease in the family. We show that C20orf7 is peripherally associated with the matrix face of the mitochondrial inner membrane and that silencing its expression with RNAi decreases complex I activity.
C20orf7 patient fibroblasts showed an almost complete absence of complex I holoenzyme and were defective at an early stage of complex I assembly, but in a manner distinct from the assembly defects caused by mutations in the assembly factor NDUFAF1. Our results indicate that C20orf7 is crucial in the assembly of complex I and that mutations in
C20orf7 cause mitochondrial disease.
Objectives
Traditional fat contouring is now regularly performed using numerous office‐based less invasive techniques. However, some limitations of these minimally invasive techniques include high ...cost or limited selectivity with performing localized contouring and reduction of fat. These shortcomings may potentially be addressed by electrochemical lipolysis (ECLL), a novel approach that involves the insertion of electrodes into tissue followed by application of a direct current (DC) electrical potential. This results in the hydrolysis of tissue water creating active species that lead to fat necrosis and apoptosis. ECLL can be accomplished using a simple voltage‐driven system (V‐ECLL) or a potential‐driven feedback cell (P‐ECLL) both leading to water electrolysis and the creation of acid and base in situ. The aim of this study is to determine the long‐lasting effects of targeted ECLL in a Yucatan pig model.
Methods
A 5‐year‐old Yucatan pig was treated with both V‐ECLL and P‐ECLL in the subcutaneous fat layer using 80:20 platinum:iridium needle electrodes along an 8 cm length. Dosimetry parameters included 5 V V‐ECLL for 5, 10, and 20 minutes, and −1.5 V P‐ECLL, −2.5 V P‐ECLL, −3.5 V P‐ECLL for 5 minutes. The pig was assessed for changes in fat reduction over 3 months with digital photography and ultrasound. After euthanasia, tissue sections were harvested and gross pathology and histology were examined.
Results
V‐ECLL and P‐ECLL treatments led to visible fat reduction (12.1%–27.7% and 9.4%–40.8%, respectively) and contour changes across several parameters. An increased reduction of the superficial fat layer occurred with increased dosimetry parameters with an average charge transfer of 12.5, 24.3, and 47.5 C transferred for 5 V V‐ECLL for 5, 10, and 20 minutes, respectively, and 2.0, 11.5, and 24.0 C for −1.5 V P‐ECLL, −2.5 V P‐ECLL, −3.5 V P‐ECLL for 5 minutes, respectively. These dose‐dependent changes were also evidenced by digital photography, gross pathology, ultrasound imaging, and histology.
Conclusions
ECLL results in selective damage and long‐lasting changes to the adipose layer in vivo. These changes are dose‐dependent, thus allowing for more precise contouring of target areas. P‐ECLL has greater efficiency and control of total charge transfer compared to V‐ECLL, suggesting that a low‐voltage potentiostat treatment can result in fat apoptosis equivalent to a high‐voltage DC system.
ObjectiveTo determine the SARS-CoV-2 seroprevalence among school workers within the Greater Vancouver area, British Columbia, Canada, after the first Omicron wave.DesignCross-sectional study by ...online questionnaire, with blood serology testing.SettingThree main school districts (Vancouver, Richmond and Delta) in the Vancouver metropolitan area.ParticipantsActive school staff enrolled from January to April 2022, with serology testing between 27 January and 8 April 2022. Seroprevalence estimates were compared with data obtained from Canadian blood donors weighted over the same sampling period, age, sex and postal code distribution.Primary and secondary outcomesSARS-CoV-2 nucleocapsid antibody testing results adjusted for test sensitivity and specificity, and regional variation across school districts using Bayesian models.ResultsOf 1850 school staff enrolled, 65.8% (1214/1845) reported close contact with a COVID-19 case outside the household. Of those close contacts, 51.5% (625/1214) were a student and 54.9% (666/1214) were a coworker. Cumulative incidence of COVID-19 positive testing by self-reported nucleic acid or rapid antigen testing since the beginning of the pandemic was 15.8% (291/1845). In a representative sample of 1620 school staff who completed serology testing (87.6%), the adjusted seroprevalence was 26.5% (95% CrI 23.9% to 29.3%), compared with 32.4% (95% CrI 30.6% to 34.5%) among 7164 blood donors.ConclusionDespite frequent COVID-19 exposures reported, SARS-CoV-2 seroprevalence among school staff in this setting remained no greater than the community reference group. Results are consistent with the premise that many infections were acquired outside the school setting, even with Omicron.
PDF
