Several recent studies have evidenced the relevance of machine-learning for soil salinity mapping using Sentinel-2 reflectance as input data and field soil salinity measurement (i.e., Electrical ...Conductivity-EC) as the target. As soil EC monitoring is costly and time consuming, most learning databases used for training/validation rely on a limited number of soil samples, which can affect the model consistency. Based on the low soil salinity variation at the Sentinel-2 pixel resolution, this study proposes to increase the learning database's number of observations by assigning the EC value obtained on the sampled pixel to the eight neighboring pixels. The method allowed extending the original learning database made up of 97 field EC measurements (OD) to an enhanced learning database made up of 691 observations (ED). Two classification machine-learning models (i.e., Random Forest-RF and Support Vector Machine-SVM) were trained with both OD and ED to assess the efficiency of the proposed method by comparing the models' outcomes with EC observations not used in the models´ training. The use of ED led to a significant increase in both models' consistency with the overall accuracy of the RF (SVM) model increasing from 0.25 (0.26) when using the OD to 0.77 (0.55) when using ED. This corresponds to an improvement of approximately 208% and 111%, respectively. Besides the improved accuracy reached with the ED database, the results showed that the RF model provided better soil salinity estimations than the SVM model and that feature selection (i.e., Variance Inflation Factor-VIF and/or Genetic Algorithm-GA) increase both models´ reliability, with GA being the most efficient. This study highlights the potential of machine-learning and Sentinel-2 image combination for soil salinity monitoring in a data-scarce context, and shows the importance of both model and features selection for an optimum machine-learning set-up.
•This study analyzes the temporal evolution of the goundwater storage of the Amazon Basin over 2003–2010.•Seasonal variations of groundwater storage represent between 20 and 35% of the terrestrial ...water storage seasonal volume variations of the Amazon.•Anomalies of groundwater storage exhibit a strong interannual variability in response to hydrologic events such as the extreme drought that occurred in 2005.
In large Tropical River basins such as the Amazon, groundwater plays a major role in the water and ecological cycles with large influences on the rainforest ecosystems and climate variability. However, due to the lack of monitoring networks, Amazon groundwater storage and its variability remain poorly known. Here, we provide an unprecedented direct estimate of the spatio-temporal variations of the anomaly of groundwater storage over the period January 2003 -September 2010 in the Amazon Basin by decomposing the total terrestrial water storage measured by the Gravity Recovery and Climate Experiment (GRACE) mission into the individual contributions of other hydrological reservoirs, using multi-satellite data for the surface waters and floodplains and models outputs for the soil moisture. We show that the seasonal variations of groundwater storage represent between 20 and 35% of the terrestrial water storage seasonal volume variations of the Amazon. Larger seasonal amplitudes of groundwater storage (>450 mm) are found in the Alter do Chão and Iça aquifers in the central part of the Amazon Basin. Anomalies of groundwater storage exhibit a strong interannual variability (STD reaching 120 mm along the central corridor) during the study period in response to hydrologic variability and climatic events such as the extreme drought that occurred in 2005.
There is increasing evidence to indicate that nutrition is an important factor involved in the onset and development of several chronic human diseases including cancer, cardiovascular disease (CVD), ...type II diabetes and obesity. Clinical studies implicate excessive consumption of medium-chain saturated fatty acids (SFA) and trans-fatty acids (TFA) as risk factors for CVD, and in the aetiology of other chronic conditions. Ruminant-derived foods are significant sources of medium-chain SFA and TFA in the human diet, but also provide high-quality protein, essential micronutrients and several bioactive lipids. Altering the fatty acid composition of ruminant-derived foods offers the opportunity to align the consumption of fatty acids in human populations with public health policies without the need for substantial changes in eating habits. Replacing conserved forages with fresh grass or dietary plant oil and oilseed supplements can be used to lower medium-chain and total SFA content and increase cis-9 18:1, total conjugated linoleic acid (CLA), n-3 and n-6 polyunsaturated fatty acids (PUFA) to a variable extent in ruminant milk. However, inclusion of fish oil or marine algae in the ruminant diet results in marginal enrichment of 20- or 22-carbon PUFA in milk. Studies in growing ruminants have confirmed that the same nutritional strategies improve the balance of n-6/n-3 PUFA, and increase CLA and long-chain n-3 PUFA in ruminant meat, but the potential to lower medium-chain and total SFA is limited. Attempts to alter meat and milk fatty acid composition through changes in the diet fed to ruminants are often accompanied by several-fold increases in TFA concentrations. In extreme cases, the distribution of trans 18:1 and 18:2 isomers in ruminant foods may resemble that of partially hydrogenated plant oils. Changes in milk fat or muscle lipid composition in response to diet are now known to be accompanied by tissue-specific alterations in the expression of one or more lipogenic genes. Breed influences both milk and muscle fat content, although recent studies have confirmed the occurrence of genetic variability in transcript abundance and activity of enzymes involved in lipid synthesis and identified polymorphisms for several key lipogenic genes in lactating and growing cattle. Although nutrition is the major factor influencing the fatty acid composition of ruminant-derived foods, further progress can be expected through the use of genomic or marker-assisted selection to increase the frequency of favourable genotypes and the formulation of diets to exploit this genetic potential.
Summary
Anaphylaxis in pregnancy is a rare but severe complication for both mother and infant. Population‐based data on anaphylaxis in pregnancy are lacking from mainland European countries. This ...multinational study presents the incidence, causative agents, management and maternal and infant outcomes of anaphylaxis in pregnancy. This descriptive multinational study used a combination of retrospective (Finnish medical registries) and prospective population‐based studies (UK, France, Belgium and the Netherlands) to identify cases of anaphylaxis. Sixty‐five cases were identified among 4,446,120 maternities (1.5 per 100,000 maternities; 95%CI 1.1–1.9). The incidence did not vary between countries. Approximately three‐quarters of reactions occurred at the time of delivery. The most common causes were antibiotics in 27 women (43%), and anaesthetic agents in 11 women (17%; including neuromuscular blocking drugs, 7), which varied between countries. Anaphylaxis had very poor outcomes for one in seven mothers and one in seven babies; the maternal case fatality rate was 3.2% (95%CI 0.4–11.0) and the neonatal encephalopathy rate was 14.3% (95%CI 4.8–30.3). Across Europe, anaphylaxis related to pregnancy is rare despite having a multitude of causative agents and different antibiotic prophylaxis protocols.
Summary
Anaemia is frequently diagnosed during pregnancy. However, there are few data regarding its incidence, and the association with severe maternal morbidity remains uncertain and potentially ...biased in high‐resource countries. The purpose of this study was to explore the association between gestational anaemia and severe acute maternal morbidity during and after delivery. We performed a cohort‐nested case‐control analysis from the epidemiology of severe maternal mortality (EPIMOMS) prospective study conducted in six French regions (2012–2013, n = 182,309 deliveries). There were 1669 women with severe acute maternal morbidity during or after delivery, according to a standardised definition obtained by expert consensus. The control group were randomly selected among women without severe morbidity who delivered in the same health centres (n = 3234). We studied the association between gestational anaemia and severe acute maternal morbidity during or after delivery overall, by cause, and by mode of delivery, using multivariable logistic regression and multiple imputation. Gestational anaemia was significantly more frequent in women with severe acute maternal morbidity (25.3%) than in controls (16.3%), p < 0.001, and mostly mild in both groups. After adjustment for confounders, women with gestational anaemia were at increased risk of overall severe acute maternal morbidity during and after delivery (adjusted OR (95%CI) 1.8 (1.5–2.1)). This association was also found for severe postpartum haemorrhage (adjusted OR (95%CI) 1.7 (1.5–2.0)), even after omitting the transfusion criterion (adjusted OR (95%CI) 1.9 (1.6–2.3)), and for severe acute maternal morbidity secondary to causes other than haemorrhage or pregnancy‐related hypertensive disorders (adjusted OR (95%CI) 2.7 (1.9–4.0)). These results highlight the importance of optimising the diagnosis and management of anaemia during pregnancy.
Summary
The aim of this systematic review was to develop recommendations for the management of postoperative pain after primary elective total hip arthroplasty, updating the previous ...procedure‐specific postoperative pain management (PROSPECT) guidelines published in 2005 and updated in July 2010. Randomised controlled trials and meta‐analyses published between July 2010 and December 2019 assessing postoperative pain using analgesic, anaesthetic, surgical or other interventions were identified from MEDLINE, Embase and Cochrane databases. Five hundred and twenty studies were initially identified, of which 108 randomised trials and 21 meta‐analyses met the inclusion criteria. Peri‐operative interventions that improved postoperative pain include: paracetamol; cyclo‐oxygenase‐2‐selective inhibitors; non‐steroidal anti‐inflammatory drugs; and intravenous dexamethasone. In addition, peripheral nerve blocks (femoral nerve block; lumbar plexus block; fascia iliaca block), single‐shot local infiltration analgesia, intrathecal morphine and epidural analgesia also improved pain. Limited or inconsistent evidence was found for all other approaches evaluated. Surgical and anaesthetic techniques appear to have a minor impact on postoperative pain, and thus their choice should be based on criteria other than pain. In summary, the analgesic regimen for total hip arthroplasty should include pre‐operative or intra‐operative paracetamol and cyclo‐oxygenase‐2‐selective inhibitors or non‐steroidal anti‐inflammatory drugs, continued postoperatively with opioids used as rescue analgesics. In addition, intra‐operative intravenous dexamethasone 8–10 mg is recommended. Regional analgesic techniques such as fascia iliaca block or local infiltration analgesia are recommended, especially if there are contra‐indications to basic analgesics and/or in patients with high expected postoperative pain. Epidural analgesia, femoral nerve block, lumbar plexus block and gabapentinoid administration are not recommended as the adverse effects outweigh the benefits. Although intrathecal morphine 0.1 mg can be used, the PROSPECT group emphasises the risks and side‐effects associated with its use and provides evidence that adequate analgesia may be achieved with basic analgesics and regional techniques without intrathecal morphine.
요약
이 체계적 문헌 고찰의 목적은 2005년에 출판되고 2010년 7월에 업데이트된 시술별로 특화 된 수 술 후 통 증 관 리 (PROSPECT)의 이전 지침을 업데이트하여 인공 고관절 전치 환술 후의 통증 관리에 대한 권고사항을 개발하는 것이었다. 진통제, 마취, 수술 또는 다른 중재를 사용하고 수술 후 통증을 평가한, 2010년 7월과 2019년 12월 사이에 출판된 무작위 대조 시험들과 메타분석들을 MEDLINE, Embase, Cochrane 데이 터베이스로부터 검색하였다. 일차적으로 520건의 연구가 확인 되었고, 그중 108건의 무작위 시험과 21건의 메타분석이 기준 을 충족하였다. 수술 후 통증을 개선한 주술기 중재들은 파라 세타몰(paracetamol), 사이클로옥시게나제‐2 (COX‐2) 선택 적 억제제, 비스테로이드성 소염제, 덱사메타손(dexametha‐ sone) 정맥 주입 등이 있다. 또한, 말초신경차단(대퇴신경차 단, 요추신경총차단, 장골근막차단), 일회성 국소침윤마취, 경 막내 모르핀과 경막외 진통제 투여도 통증을 개선시켰다. 이 외에 평가된 다른 모든 진통 방법들에 대해서는 증거가 불충 분하였다. 수술과 마취 방법들이 수술 후 통증에 미치는 영향 은 미미한 것으로 보이므로, 이들의 선택은 통증 이외 기준에 따라 이루어져야 한다. 요약하면, 인공 고관절 전치환술을 위 한 진통 요법은 수술 전 또는 수술 중 파라세타몰과 사이클로 옥시제나제‐2 선택적 억제제 또는 비스테로이드성 소염제를 포함해야 하며, 수술 후에는 이들의 지속적인 복용 및 구조 진통 요법으로 아편유사제 사용이 동반되어야 한다. 또한, 수 술 중 8‐10 mg의 덱사메타손 정맥 주사가 권장된다. 특히 기 본 진통제에 대한 금기사항이 있거나 수술 후 강한 통증이 예 상되는 환자들의 경우, 장골근막차단이나 국소침윤마취와 같 은 부위 진통 기술들이 권장된다. 경막외 진통제, 대퇴신경차 단, 요추신경총차단과 가바펜티노이드(gabapentinoid) 투여 는 부작용이 이점보다 크기 때문에 권장되지 않는다. 경막내 모르핀 0.1 mg이 사용될 수는 있지만, PROSPECT 그룹은 이 러한 사용과 관련된 위험과 부작용들을 강조하고, 경막내 모 르핀 없이도 기본적 진통제와 부위 진통 기법들로 충분한 진 통이 이루어질 수 있다는 증거를 제공한다.
Abstract
Six gridded temperature datasets (T‐datasets) were evaluated for the first time over the South American continent, through the case study of Bolivia, by comparing them with temperature ...records acquired from 82 meteorological stations spanning the 1995–2010 period. The comparisons were carried out at the daily time step considering different seasons (annual scale, austral summer and austral winter) and regions (Amazon, La Plata and Altiplano basins). Overall, the climate hazards group infrared temperature with stations (CHIRTS) and the climate prediction centre (CPC) T‐datasets provided the most reliable mean daily temperature (
T
mean
) and also described well the temporal variability of minimum and maximum daily temperature estimates (
T
n
and
T
x
).
T
mean
,
T
n
and
T
x
trends were analysed over the 1983–2016 period to observe temperature temporal evolution across the three regions. Despite some general agreements between the trends (
T
mean
,
T
x
and
T
n
), large discrepancies are also observed. It was found that CPC overestimates and CHIRTS underestimates mean temperature trends and that CPC (CHIRTS) was better than CHIRTS (CPC) to estimate
T
x
(
T
n
) trends, both in magnitude and space. Furthermore, opposing trends (i.e., warming and cooling) are described by CPC and CHIRTS for some specific regions, which call into question their reliability for such analyses. These findings highlight the need to validate gridded temperature products with reliable ground data for the regions under study, particularly if they have a wide elevation range.
Microbiology has been largely developed thanks to the discovery and optimization of culture media. The first liquid artificial culture medium was created by Louis Pasteur in 1860. Previously, ...bacterial growth on daily materials such as some foods had been observed. These observations highlighted the importance of the bacteria's natural environment and their nutritional needs in the development of culture media for their isolation. A culture medium is essentially composed of basic elements (water, nutrients), to which must be added different growth factors that will be specific to each bacterium and necessary for their growth.
The evolution of bacterial culture through the media used for their culture began with the development of the first solid culture medium by Koch, allowing not only the production of bacterial colonies, but also the possibility of purifying a bacterial clone. The main gelling agent used in solid culture media is agar. However, some limits have been observed in the use of agar because of some extremely oxygen-sensitive bacteria that do not grow on agar media, and other alternatives were proposed and tested. Then, the discovery of antimicrobial agents and their specific targets prompted the emergence of selective media. These inhibiting agents make it possible to eliminate undesirable bacteria from the microbiota and select the bacteria desired. Thanks to a better knowledge of the bacterial environment, it will be possible to develop new culture media and new culture conditions, better adapted to certain fastidious bacteria that are difficult to isolate.
We update the ephemeris of the eclipsing high-mass X-ray binary (HMXB) systems LMC X-4, Cen X-3, 4U 1700-377, 4U 1538-522, SMC X-1, IGR J18027-2016, Vela X-1,IGR J17252-3616, XTE J1855-026, and OAO ...1657-415 with the help of more than ten years of monitoring these sources with the All Sky Monitor onboard RXTE and with the Integral Soft Gamma-Ray Imager onboard INTEGRAL. These results are used to refine previous measurements of the orbital period decay of all sources (where available) and provide the first accurate values of the apsidal advance in Vela X-1 and 4U 1538-522. Updated values for the masses of the neutron stars hosted in the ten HMXBs are also provided, as well as the long-term light curves folded on the best determined orbital parameters of the sources. These light curves reveal complex eclipse ingresses and egresses that are understood mostly as being caused by accretion wakes. Our results constitute a database to be used for population and evolutionary studies of HMXBs and for theoretical modeling of long-term accretion in wind-fed X-ray binaries.
Abstract
Some polars show quasi-periodic oscillations (QPOs) in their optical light curves that have been interpreted as the result of shock oscillations driven by the cooling instability. Although ...numerical simulations can recover this physics, they wrongly predict QPOs in the X-ray luminosity and have also failed to reproduce the observed frequencies, at least for the limited range of parameters explored so far. Given the uncertainties on the observed polar parameters, it is still unclear whether simulations can reproduce the observations. The aim of this work is to study QPOs covering all relevant polars showing QPOs. We perform numerical simulations including gravity, cyclotron and bremsstrahlung radiative losses, for a wide range of polar parameters, and compare our results with the astronomical data using synthetic X-ray and optical luminosities. We show that shock oscillations are the result of complex shock dynamics triggered by the interplay of two radiative instabilities. The secondary shock forms at the acoustic horizon in the post-shock region in agreement with our estimates from steady-state solutions. We also demonstrate that the secondary shock is essential to sustain the accretion shock oscillations at the average height predicted by our steady-state accretion model. Finally, in spite of the large explored parameter space, matching the observed QPO parameters requires a combination of parameters inconsistent with the observed ones. This difficulty highlights the limits of one-dimensional simulations, suggesting that multi-dimensional effects are needed to understand the non-linear dynamics of accretion columns in polars and the origins of QPOs.
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