508 research outputs found
Comparison of solar radio and EUV synoptic limb charts during the present solar maximum
The present solar cycle is particular in many aspects: it had a delayed
rising phase, it is the weakest of the last 100 years, and it presents two
peaks separated by more than one year. To understand the impact of these
characteristics on the solar chromosphere and coronal dynamics, images from a
wide wavelength range are needed. In this work we use the 17~GHz radio
continuum, formed in the upper chromosphere and the EUV lines 304 and
171~{\AA}, that come from the transition region (He II) and the corona (Fe IX,
X), respectively. We analyze daily images at 304 and 171~{\AA} obtained by the
Atmospheric Imaging Assembly (AIA). The 17~GHz maps were obtained by the
Nobeyama Radioheliograph (NoRH). To construct synoptic limb charts, we
calculated the mean emission of delimited limb areas with 100" wide and angular
separation of . At the equatorial region, the results show an
hemispheric asymmetry of the solar activity. The northern hemisphere dominance
is coincident with the first sunspot number peak, whereas the second peak
occurs concurrently with the increase in the activity at the south. The polar
emission reflects the presence of coronal holes at both EUV wavelengths,
moreover, the 17~GHz polar brightenings can be associated with the coronal
holes. Until 2013, both EUV coronal holes and radio polar brightenings were
more predominant at the south pole. Since then they have not been apparent in
the north, but thus appear in the beginning of 2015 in the south as observed in
the synoptic charts. This work strengthens the association between coronal
holes and the 17~GHz polar brightenings as it is evident in the synoptic limb
charts, in agreement with previous case study papers. The enhancement of the
radio brightness in coronal holes is explained by the presence of bright
patches closely associated with the presence of intense unipolar magnetic
fields.Comment: 6 pages, 5 figures. Acccepted for publication in Astronomy &
Astrophysic
Modelling the habitat preferences of the NE-Atlantic Sea cucumber Holothuria forskali : demographics and abundance
This work was funded by the Operational Program Mar2020 MAR-02.01.01-FEAMP-0052 âNewcumber - Avanços para o cultivo sustentĂĄvel de pepinos do marâ. This work was also supported by national funds through FCT - Fundação para a CiĂȘncia e a Tecnologia, I.P., within the scope of the projects (https://doi.org/10.54499/UIDB/04292/2020, and https://doi.org/10.54499/UIDB/00006/2020) and the Associate Laboratory ARNET (https://doi.org/10.54499/LA/P/0069/2020), A.C. Brito with the Scientific Stimulus Program â CEECIND/00095/2017, A.P. with the under the Scientific Employment Stimulus - Institutional Call - CEECINST/00051/2018 and Francisco Azevedo e Silva and JoĂŁo Trigo de Sousa through the individual grants (SFRH/BD/09563/2020 and SFRH/BDANA/02949/2023).Sea cucumbers' historical demand, together with the depletion of several traditional species in the market, has popularized new target species from new fishing grounds. Holothuria forskali is one of those emergent species in the trade market. However, it is a species for which there is no relevant information to allow sustainable stock management. Fundamental knowledge of the populations' structure and habitat preferences are key elements without which any measure is inconsequent. This work aims to fill that gap by modelling temporal and spatial patterns of abundance and demographic structure of this species in a NE-Atlantic area, as a function of environmental features. For a period of 15 months, nine regular sampling campaigns collected data on density, individual length, individual conditions of occurrence (e.g. sheltered, on sand, on algae cover) and environmental parameters (water column, sediment, substrate cover and type), using random transects throughout a costal rocky-reef, considering habitat heterogeneity and substrate types. To determine the species' habitat preferences Generalized Linear Models were used to model density and demographic structure of the species as a function of environmental conditions. The models revealed that the main drivers shaping the distribution of H. forskali are neither abiotic nor biotic parameters of the water column, but physical stressors, like current intensity and depth, and substrate type in a patchy distribution pattern. Estuarine conditions are generally avoided, although with a size-dependent opportunistic strategy. Larger individuals show temporal and spatial displacement patterns towards suitable reproductive conditions (pre-breeding aggregation) and favourable feeding grounds and smaller size-classes tend to aggregate in higher numbers in more stable environments. Sustainable sources for market supply, like aquaculture, are still a long way from commercial production. So, these results are fundamental to support effective conservation measures for stock management of H. forskaliPublisher PDFPeer reviewe
Allometric relationships to assess ontogenetic adaptative changes in three NE Atlantic commercial sea cucumbers (Echinodermata, Holothuroidea)
This study was financed by the Operational Program Mar2020 nÂș MAR-02.01.01-FEAMP-0052 âNewcumberâAvanços para o cultivo sustentĂĄvel de pepinos-do-marâ. It received further financial support from Fundação para a CiĂȘncia e a Tecnologia with project UIDB/04292/2020; A.C. Brito and A. Pombo through the Scientific Employment Stimulus Programmes (CEECIND/00095/2017 and CEECINST/00051/2018); and Francisco Azevedo e Silva through the individual research Grant 2020.09563.BD; Also, T. A. Marques and C. Rocha thank partial support by CEAUL (funded by FCTâFundação para a CiĂȘncia e a Tecnologia, Portugal, through the project UIDB/00006/2020).Holothuria arguinensis, Holothuria mammata and Holothuria forskali are three common sea cucumber species found in the NE Atlantic, traded in international markets and susceptible to capture. Allometric relationships reveal if the scaling relationships between biometric characters are proportional with growth, being a useful tool to understand species growth strategies. Allometric relationships of the three species were estimated and compared between them and with populations from different regions. These allometric relationships revealed that the three species have negative allometric growth. However, they have different growth strategies between them and reveal different regional intra-specific growth strategies when compared to other populations, suggesting ontogenetic adaptation as a consequence of external factors. PostprintPeer reviewe
Cardiovascular dysfunction in obesity and new diagnostic imaging techniques: the role of noninvasive image methods
Obesity is a major public health problem affecting adults and children in both developed and developing countries. This condition often leads to metabolic syndrome, which increases the risk of cardiovascular disease. A large number of studies have been carried out to understand the pathogenesis of cardiovascular dysfunction in obese patients. Endothelial dysfunction plays a key role in the progression of atherosclerosis and the development of coronary artery disease, hypertension and congestive heart failure. Noninvasive methods in the field of cardiovascular imaging, such as measuring intima-media thickness, flow-mediated dilatation, tissue Doppler, and strain, and strain rate, constitute new tools for the early detection of cardiac and vascular dysfunction. These techniques will certainly enable a better evaluation of initial cardiovascular injury and allow the correct, timely management of obese patients. The present review summarizes the main aspects of cardiovascular dysfunction in obesity and discusses the application of recent noninvasive imaging methods for the early detection of cardiovascular alterations
Pretransplant biopsy in expanded criteria donors: do we really need it?
Abstract
INTRODUCTION:
Renal transplantation is the best treatment for end-stage renal disease, including when using expanded criteria donors (ECD) kidneys. However, these suboptimal kidneys should be evaluated rigorously to meet their usefulness. Opinions differ about the best way to evaluate them.
MATERIALS AND METHODS:
We retrospectively reviewed kidneys from ECD harvested by a single academic institution between January 2008 and September 2013. Needle biopsies were performed at the time of the harvest when considered relevant by the transplant team. Two pathologists where responsible for their analysis; the Remuzzi classification has been used in all cases.
RESULTS:
We evaluated 560 ECD kidneys. Biopsies were made in 197 (35.2%) organs, 20 of which were considered not usable and 36 good only for double transplantation. Sixty-three kidneys (11.3%) were discarded by the transplant team based on the biopsy result and clinical criteria. Donors who underwent a biopsy were older (P < .001) and had a worse glomerular filtration rate (GFR; P = .001). Comparing donors approved and rejected by the biopsy, the rejected donors were heavier (P = .003) and had a lower GFR (P = .002). Cold ischemia time was longer for the biopsy group (P < .001). Regarding graft function, the biopsy overall score correlated with the transplant outcome in the short and long term. Separately, glomeruli and interstitium scores were correlated with recipient's GFR in the earlier periods (3 months; P = .025 and .037), and the arteries and tubules correlated with GFR in the longer term (at 3 years P = .004 and .010).
CONCLUSION:
The decision on the usability of ECD grafts is complex. At our center, we chose a mixed approach based on donor risk. Low-risk ECD do not require biopsy. In more complex situations, especially older donors or those with a lower GFR, prompted a pretransplant biopsy. The biopsy results proved to be useful as they relate to subsequent transplant outcomes, thereby allowing us to exclude grafts whose function would most probably be less than optimal
Human plasma derived prothrombin complex concentrate (OCTAPLEX), the HFF, EPE: Blood Department experience.
Background: The HPDPCC was introduced in our clinical practice in 2005, and it has some specific clinical recommendations . We use Octaplex mostly to recert coagulation parameters in patients whose status require their quick conversion, mainly to reverse oral anticoagulation. We initially started using Octaplex in lower doses than the recommended by the drug leaflet, trying to find an optimal dose, aiming to avoid side effects.
Aims: Our goals are to share our experience using Octaplex in clinical practice, demonstrating that we can obtain rapid results with minimal dose, without adverse events.
Methods: We only included in this study patients who have done Octaplex (1unit â 20ml) and have results of measurement of their International Normalized Ratio (INR) before and after the infusion of prothrombin complex concentrate. The INR was determined using the fully automated hemostasis analyser BCS XP System (Siemens) and the reagent Innovin (Dade Behring). The period of the study was, 2005-2010, and included 87 patients with different diseases. The INR results upper than 10 were counted like 10 because the laboratory doesnât quantify values higher than this.
Results: The patients were 64 men and 23 women, with ages ranged between 18 and 85-years-old, average 66,5-years-old 53 were under treatment with oral anticoagulants (OAC), 22 with liver impairment (1.1), and 12 with other pathologies (OP). The INR before treatment varied from 10 (maximal value) to 1.4 (minimal value), the average values were 6.72 to the patients under OAC, 2.15 to the patients with LI and 3.39 to the patients with OP. After treatment the average values were 2.0 to the OAC 1.84 to the LI and 1.76 to the OP. After treatment the maximal value of the INR was 6.9 and the minimal 0.9. The average number of units used to revert the patients clinical status were for OAC 1.62 (in an average of 1.4 number of intakes), for LI 2 units (1 intake) and for OP 2.75 units (1.42 intakes). We didnât find any adverse post-administration events.
Summary/Conclusions: We found better results in the administration of Octaplex in patients doing OAC, where the 1.62 units (in 1.04 intakes) lowered the INR average from 6.72 to 2.0. The dose used to resolve our clinical cases were much lower than the recommended in the drug leaflet. We didnât find any adverse events in this dose. The clinical practice feedback suggests a quicker INR conversion comparing to fresh frozen plasma
The influence of seasonalness on the structural characteristics of aquatic humic substances extracted from Negro River (Amazon State) waters: interactions with Hg(II).
Statistical analysis of the onset temperature of solar flares in 2010-2011
Understanding the physical processes that trigger solar flares is paramount
to help with forecasting space weather and mitigating the effects on our
technological infrastructure. A previously unknown phenomenon was recently
identified in solar flares: the plasma temperature, derived from soft X-ray
(SXR) data, at the onset of four flares, was revealed to be in the range 10-15
MK, without evidence of gradual heating. To investigate how common the
hot-onset phenomenon may be, we extend this investigation to solar flares of
B1.2- X6.9 classes recorded by the X-ray Sensor (XRS) on-board the GOES-14 and
GOES-15 satellites between 2010 and 2011. For this statistical study, we
employed the same methodology as in recent work, where the pre-flare SXR flux
of each flare is obtained manually, and the temperature and emission measure
values are obtained by the flux ratio of the two GOES/XRS channels using the
standard software. From 3224 events listed in the GOES flare catalog for
2010-2011, we have selected and analyzed 745 events for which the flare
heliographic location was provided in the list, to investigate center-to-limb
effects of the hot-onset phenomenon. Our results show that 559 out of 745
flares (75%) exhibit an onset temperature above 8.6 MK (the first quartile),
with respective log10 of the emission measure values between 46.0 - 47.25 cm-3,
indicating that small amounts of plasma are quickly heated to high
temperatures. These results suggest that the hot-onset phenomenon is very
common in solar flares.Comment: 6 pages,7 figure
A Predictive Model of Postnatal Surgical Intervention in Children With Prenatally Detected Congenital Anomalies of the Kidney and Urinary Tract
The aim of this study was to identify predictive factors and develop a model to assess individualized risk of postnatal surgical intervention in patients with antenatal hydronephrosis. This is a retrospective cohort study of 694 infants with prenatally detected congenital anomalies of kidney and urinary tract with a median follow-up time of 37 months. The main event of interest was postnatal surgical intervention. A predictive model was developed using Cox model with internal validation by bootstrap technique. Of 694 patients, 164 (24%) infants underwent surgical intervention in a median age of 7.8 months. Predictors of the surgical intervention in the model were: baseline glomerular filtration rate, associated hydronephrosis, presence of renal damage and the severity of renal pelvic dilatation. The optimism corrected c statistic for the model was 0.84 (95%CI, 0.82â0.87). The predictive model may contribute to identify infants at high risk for surgical intervention. Further studies are necessary to validate the model in patients from other settings
Modelling the distribution of a commercial NE-Atlantic sea cucumber, Holothuria mammata : demographic and abundance spatio-temporal patterns
Funding: This study was financed by the Operational Programme Mar2020, MAR-02.01.01-FEAMP-0052, âNewcumber â Avanços para o cultivo sustentĂĄvel de pepinos do marâ. It received further financial support from Fundação para a CiĂȘncia e Tecnologia (projects UIDB/04292/2020, UIDB/00006/2020, CoastNet â PINFRA/22128/2016, AB with the Scientific Stimulus Programme â CEECIND/00095/2017 and FA with the individual research grant 2020.09563.BD). This publication was financed by Portuguese national funds through FCT â Fundação IP under project reference UIDB/04292/2020, and by the European Unionâs Horizon 2020 Research and Innovation Program under grant agreement N810139: Project Portugal Twinning for Innovation and Excellence in Marine Science and Earth Observation â PORTWIMS.There is an increasing demand for sea cucumbers, for human consumption, mainly from Asian markets and, as a consequence, NE-Atlantic species are now new targets for exploitation and exportation. Holothuria mammata is one of the most valuable species in Europe. However, the lack of historical economic interest in this species in most European countries has also led to a lack of studies concerning biological and ecological aspects on wild populations and this is a major issue for stock management. This study aims to determine the temporal and spatial patterns of distribution of H. mammata, considering its abundance and demographic structure in a NE-Atlantic area, SW Portugal, as a function of environmental conditions. For that, a population from a marine protected area was followed for 1 year at 1.5-month intervals. Throughout the coastal area, six sites were selected and at each sampling campaign three random transects per site and substrate (rock and sand) in which all H. mammata individuals were counted and measured. For each site and survey several environmental parameters of interest, from the water column, the sediment and substrate cover, were also measured. Generalized Linear Models were used to model the spatial and temporal distribution of the species according to environmental conditions, to determine the speciesâ habitat preferences. The distribution models indicate that abiotic and biotic parameters of the water column are not the main drivers shaping the distribution of H. mammata. The species has a patchy distribution, and its habitat preferences depend on environmental stability, the presence of shelter and habitat complexity, which is more important for smaller, more vulnerable, individuals, while bigger size classes tend to venture more into less stable environments in an opportunistic fashion. The knowledge of these population traits is determinant to develop stock management measures, which are now urgent to prevent the depletion of commercial sea cucumber populations in the NE-Atlantic. Sustainable fisheries policies should be developed and start by considering to delimit fishing areas and periods, considering the species spatial and temporal distribution patterns.Publisher PDFPeer reviewe
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