We report a new hepatitis C virus (HCV) genotype identified in patients originating from the Democratic Republic of Congo. The prototype QC69 virus is shown to be a new lineage distinct from ...genotypes 1 to 6. Three additional patients were also found to be infected by a virus from this lineage, confirming its circulation in humans. We propose that these viruses be classified into HCV genotype 7.
BACKGROUND:Morbidity associated with cardiovascular disease is increasing in the HIV-infected population. We aimed to study the impact of HIV and of antiretrovirals on acute myocardial infarction ...(AMI).
METHODS:We performed a cohort and a nested case-control study using the dataset of the Régie de lʼAssurance Maladie du Québec. HIV-positive patients were identified using ICD-9 diagnostic codes and matched to HIV-negative patients. Within the HIV-positive cohort, cases of AMI were identified and matched to HIV-positive patients without AMI. The coprimary outcomes were the risk of AMI associated with HIV exposure in the cohort study and that associated with exposure to antiretrovirals in the case-control study. Data were analysed using Poisson and conditional logistic regression.
RESULTS:About 7053 HIV-positive patients were matched to 27,681 HIV-negative patients. Incidence rates of AMI in the HIV+ cohort was 3.88 95% confidence interval (CI) (3.26 to 4.58) per 1000 patient-years, compared to 2.21 95% CI (1.93 to 2.52) per 1000 patient-years in the HIV cohort. The adjusted incidence ratio of AMI for HIV-infected patients was 2.11 95%CI (1.69 to 2.63). Among HIV+ patients, 125 AMI cases were matched with 1084 HIV+ patients. We found increased odds ratio (95% CI) of AMI associated with any exposure to abacavir 1.79 (1.16 to 2.76), P = 0.02, efavirenz 1.83 (1.21 to 2.76) P = 0.004, lopinavir 1.98 (1.24 to 3.16) P = 0.004, and ritonavir 2.29 (1.48 to 3.54) P < 0.001.
CONCLUSIONS:HIV+ individuals were at higher risk of AMI than the general population, and several antiretrovirals were associated with an increased risk of AMI. Results should be interpreted with caution in absence of data on smoking and HIV clinical status.
The patterns of sea ice retreat in the Arctic Ocean are investigated using two global climate models (GCMs) that have profound differences in their large-scale mean winter atmospheric circulation and ...sea ice drift patterns. The Community Earth System Model Large Ensemble (CESM-LE) presents a mean sea level pressure pattern that is in general agreement with observations for the late twentieth century. The Community Climate System Model, version 4 (CCSM4), exhibits a low bias in its mean sea level pressure over the Arctic region with a deeper Icelandic low. A dynamical mechanism is presented in which large-scale mean winter atmospheric circulation has significant effect on the following September sea ice extent anomaly by influencing ice divergence in specific areas. A Lagrangian model is used to backtrack the 80°N line from the approximate time of the melt onset to its prior positions throughout the previous winter and quantify the divergence across the Pacific and Eurasian sectors of the Arctic. It is found that CCSM4 simulates more sea ice divergence in the Beaufort and Chukchi Seas and less divergence in the Eurasian seas when compared to CESM-LE, leading to a Pacificcentric sea ice retreat. On the other hand, CESM-LE shows a more symmetrical retreat between the Pacific, Eurasian, and Atlantic sectors of the Arctic. Given that a positive trend in the Arctic Oscillation (AO) index, associated with low sea level pressure anomalies in the Arctic, is a robust feature of GCMs participating in phase 5 of the Coupled Model Intercomparison Project (CMIP5), these results suggest that the sea ice retreat in the Pacific sector could be amplified during the transition to a seasonal ice cover.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Myeloid cells such as monocytes, dendritic cells (DC) and macrophages (MΦ) are key components of the innate immune system contributing to the maintenance of tissue homeostasis and the ...development/resolution of immune responses to pathogens. Monocytes and DC, circulating in the blood or infiltrating various lymphoid and non-lymphoid tissues, are derived from distinct bone marrow precursors and are typically short lived. Conversely, recent studies revealed that subsets of tissue resident MΦ are long-lived as they originate from embryonic/fetal precursors that have the ability to self-renew during the life of an individual. Pathogens such as the human immunodeficiency virus type 1 (HIV-1) highjack the functions of myeloid cells for viral replication (e.g., MΦ) or distal dissemination and cell-to-cell transmission (e.g., DC). Although the long-term persistence of HIV reservoirs in CD4+ T-cells during viral suppressive antiretroviral therapy (ART) is well documented, the ability of myeloid cells to harbor replication competent viral reservoirs is still a matter of debate. This review summarizes the current knowledge on the biology of monocytes and DC during homeostasis and in the context of HIV-1 infection and highlights the importance of future studies on long-lived resident MΦ to HIV persistence in ART-treated patients.
The frequency-following response with origin in the auditory brainstem represents the pitch contour of voice and can be recorded with electrodes from the scalp. MEG studies also revealed a cortical ...contribution to the high gamma oscillations at the fundamental frequency (f0) of a vowel stimulus. Therefore, studying the cortical component of the frequency-following response could provide insights into how pitch information is encoded at the cortical level. Comparing how aging affects the different responses may help to uncover the neural mechanisms underlying speech understanding deficits in older age. We simultaneously recorded EEG and MEG responses to the syllable /ba/. MEG beamformer analysis localized sources in bilateral auditory cortices and the midbrain. Time-frequency analysis showed a faithful representation of the pitch contour between 106 Hz and 138 Hz in the cortical activity. A cross-correlation revealed a latency of 20 ms. Furthermore, stimulus onsets elicited cortical 40-Hz responses. Both the 40-Hz and the f0 response amplitudes increased in older age and were larger in the right hemisphere. The effects of aging and laterality of the f0 response were evident in the MEG only, suggesting that both effects were characteristics of the cortical response. After comparing f0 and N1 responses in EEG and MEG, we estimated that approximately one-third of the scalp-recorded f0 response could be cortical in origin. We attributed the significance of the cortical f0 response to the precise timing of cortical neurons that serve as a time-sensitive code for pitch.
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•MEG source activity reveals cortical gamma oscillations phase-locked to vocal pitch.•High-frequency oscillation control precise timing for a cortical neural code of pitch.•Vocal pitch and 40-Hz gamma responses are right lateralized and increase in older age.•Simultaneous EEG and MEG allow estimating subcortical and cortical contributions.
This study focuses on errors in extreme precipitation in gridded station products incurred during the upscaling of station measurements to a grid, referred to as representativeness errors. Gridded ...precipitation station analyses are valuable observational data sources with a wide variety of applications, including model validation. The representativeness errors associated with two gridding methods are presented, consistent with either a point or areal average interpretation of model output, and it is shown that they differ significantly (up to 30%). An experiment is conducted to determine the errors associated with station density, through repeated gridding of station data within the United States using subsequently fewer stations. Two distinct error responses to reduced station density are found, which are attributed to differences in the spatial homogeneity of precipitation distributions. The error responses characterize the eastern and western United States, which are respectively more and less homogeneous. As the station density decreases, the influence of stations farther from the analysis point increases, and therefore, if the distributions are inhomogeneous in space, the analysis point is influenced by stations with very different precipitation distributions. Finally, ranges of potential percent representativeness errors of the median and extreme precipitation across the United States are created for high-resolution (0.25°) and low-resolution areal averaged (0.9° lat × 1.25° lon) precipitation fields. For example, the range of the representativeness errors is estimated, for annual extreme precipitation, to be from +16% to −12% in the low-resolution data, when station density is 5 stations per 0.9° lat × 1.25° lon grid box.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Fifth Eriksholm Workshop on “Hearing Impairment and Cognitive Energy” was convened to develop a consensus among interdisciplinary experts about what is known on the topic, gaps in knowledge, the ...use of terminology, priorities for future research, and implications for practice. The general term cognitive energy was chosen to facilitate the broadest possible discussion of the topic. It goes back to who described the effects of attention on perception; he used the term psychic energy for the notion that limited mental resources can be flexibly allocated among perceptual and mental activities. The workshop focused on three main areas(1) theories, models, concepts, definitions, and frameworks; (2) methods and measures; and (3) knowledge translation. We defined effort as the deliberate allocation of mental resources to overcome obstacles in goal pursuit when carrying out a task, with listening effort applying more specifically when tasks involve listening. We adapted Kahneman’s seminal (1973) Capacity Model of Attention to listening and proposed a heuristically useful Framework for Understanding Effortful Listening (FUEL). Our FUEL incorporates the well-known relationship between cognitive demand and the supply of cognitive capacity that is the foundation of cognitive theories of attention. Our FUEL also incorporates a motivation dimension based on complementary theories of motivational intensity, adaptive gain control, and optimal performance, fatigue, and pleasure. Using a three-dimensional illustration, we highlight how listening effort depends not only on hearing difficulties and task demands but also on the listener’s motivation to expend mental effort in the challenging situations of everyday life.
Arctic Air Masses in a Warming World Gervais, Melissa; Atallah, Eyad; Gyakum, John R. ...
Journal of climate,
04/2016, Letnik:
29, Številka:
7
Journal Article
Recenzirano
Odprti dostop
An important aspect of understanding the impacts of climate change on society is determining how the distribution of weather regimes will change. Arctic amplification results in greater warming over ...the Arctic compared to themidlatitudes, and this study examines howpatterns ofArctic airmasseswill be affected. The authors employ the Community Earth System Model Large Ensemble (CESM-LE) RCP 8.5, consisting of 30 ensemble members run through the twenty-first century. Self-organizing maps are used to define archetypes of 850-hPa equivalent potential temperature θ
e850 anomalies with respect to a changing climate and assess changes in their frequency of occurrence. In the model, a pattern with negative θ
e850 anomalies over the central Arctic becomes less frequent in the future. There is also an increase in the frequency of patterns associated with an amplified ridge (trough) with positive (negative) θ
e850 anomalies over western (eastern) North America. It is hypothesized that the increase in frequency of such patterns is the result of enhanced forcing of baroclinic waves owing to reduced sea ice over the western Arctic. There is also a decline in patterns that have anomalously high θ
e850 over the North Atlantic, a pattern that is associated with intense ridging in the 500-hPa flow over the North Atlantic and colder θ
e850 over Europe. The authors relate the decrease of these patterns to an enhancement of the North Atlantic jet induced by a warming deficit in the North Atlantic Ocean.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•A single live oral bivalent F4/F18 vaccine was administered to pigs in drinking water.•Vaccination prevented post-weaning diarrhea due to F4-enterotoxigenic E. coli (ETEC) infection and F18-ETEC in ...pigs within 7 days.•Oral bivalent F4/F18 vaccine reduced faecal shedding of F4-ETEC and F18-ETEC and resulted in heavier pigs.•Cross-protection of the F18ac vaccine strain against F18ab-E. coli pathogenic strain was demonstrated by challenge.•Oral bivalent F4/F18 vaccine elicited specific anti-F4 and anti-F18 IgM and IgA.
F4- and F18-positive enterotoxigenic E. coli strains (F4-ETEC and F18-ETEC) are important causes of post-weaning diarrhea (PWD) in pigs. F4 (antigenic variant ac) and F18 (ab and ac) fimbriae are major antigens that play an important role in the early stages of infection. Herein, the efficacy of a live oral vaccine consisting of two non-pathogenic E. coli strains, one F4ac- and one F18ac-positive, was evaluated using F4ac-ETEC and F18ab-ETEC challenge models. A randomized, masked, placebo-controlled, block design, parallel-group confirmatory study with two different vaccination-challenge intervals (7 and 21 days) was conducted for each challenge model. The vaccine was administered in one dose, to ≥18-day-old piglets via drinking water. Efficacy was assessed by evaluating diarrhea, clinical observations, weight gain and fecal shedding of F4-ETEC or F18-ETEC. Anti-F4 and anti-F18 immunoglobulins in blood were measured.
The vaccination resulted in significant reductions in clinical PWD and fecal shedding of F4-ETEC and F18-ETEC after the 7- and 21-day-post-vaccination heterologous challenges, except for after the 21-day-post-vaccination F4-ETEC challenge, when the clinical PWD was too mild to demonstrate efficacy. A significant reduction of mortality and weight loss by vaccination were observed following the F18-ETEC challenge. The 7-day protection was associated with induction of anti-F4 and anti-F18 IgM, whereas the 21-day protection was mainly associated with anti-F4 and anti-F18 IgA. The 7-day onset and 21-day duration of protection induced by this vaccine administered once in drinking water to pigs of at least 18days of age were confirmed by protection against F4-ETEC and F18-ETEC, and induction of F4 and F18-specific immunity. Cross protection of the vaccine against F18ab-E. coli was demonstrated for both the 7- and 21-day F18-ETEC challenges.