Improving the structural scope: A catalytic asymmetric 1,3‐dipolar cycloaddition involving α‐iminonitriles as azomethine precursors has been developed. In the presence of AgOAc/Taniaphos as the ...catalyst system the reaction of α‐iminonitriles with dimethyl fumarate and N‐methyl maleimide affords 2‐cyanopyrrolidines with good endo selectivity and enantioselectivity (68–≥99 % ee; see scheme).
EUS is a high-skill technique that requires numerous procedures to achieve competence. However, training facilities are limited worldwide. Convolutional neural network (CNN) models have been ...previously implemented for object detection. We developed 2 EUS-based CNN models for normal anatomic structure recognition during real-time linear- and radial-array EUS evaluations.
The study was performed from February 2020 to June 2022. Consecutive patient videos of linear- and radial-array EUS videos were recorded. Expert endosonographers identified and labeled 20 normal anatomic structures within the videos for training and validation of the CNN models. Initial CNN models (CNNv1) were developed from 45 videos and the improved models (CNNv2) from an additional 102 videos. CNN model performance was compared with that of 2 expert endosonographers.
CNNv1 used 45,034 linear-array EUS frames and 21,063 radial-array EUS frames. CNNv2 used 148,980 linear-array EUS frames and 128,871 radial-array EUS frames. Linear-array CNNv1 and radial-array CNNv1 achieved a 75.65% and 71.36% mean average precision (mAP) with a total loss of .19 and .18, respectively. Linear-array CNNv2 obtained an 88.7% mAP with a .06 total loss, whereas radial-array CNNv2 achieved an 83.5% mAP with a .07 total loss. CNNv2 accurately detected all studied normal anatomic structures with a >98% observed agreement during clinical validation.
The proposed CNN models accurately recognize the normal anatomic structures in prerecorded videos and real-time EUS. Prospective trials are needed to evaluate the impact of these models on the learning curves of EUS trainees.
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We aimed to assess the main causes of intensive care unit (ICU) readmissions in lung transplant adults and to identify independent predictors of ICU mortality (primary end-point).This Spanish ...five-centre prospective cohort study enrolled all lung transplant adults with ICU readmissions after post-transplant ICU discharge between 2012 and 2016. Patients were followed until hospital discharge or death.153 lung transplant recipients presented 174 ICU readmissions at a median (interquartile range) of 6 (2-25) months post-transplant. Chronic lung allograft dysfunction was reported in 39 (25.5%) recipients, 13 of whom (all exitus) had restrictive allograft syndrome (RAS). Acute respiratory failure (ARF) (110 (71.9%)) was the main condition requiring ICU readmission. Graft rejection (six (5.4%) acute) caused only 12 (10.8%) readmissions whereas pneumonia (56 (36.6%)) was the main cause (50 admitted for ARF and six for shock), with
(50% multidrug resistant) being the predominant pathogen. 55 (35.9%) and 69 (45.1%) recipients died in the ICU and the hospital, respectively. Bronchiolitis obliterans syndrome (BOS) stage 2 (adjusted OR (aOR) 7.2 (95% CI 1.0-65.7)), BOS stage 3 (aOR 13.7 (95% CI 2.5-95.3)), RAS (aOR >50) and pneumonia at ICU readmission (aOR 2.5 (95% CI 1.0-7.1)) were identified in multivariate analyses as independent predictors of ICU mortality. Only eight (5.2%) patients had positive donor-specific antibodies prior to ICU readmission and this variable did not affect the model.ARF was the main condition requiring ICU readmission in lung transplant recipients and was associated with high mortality. Pneumonia was the main cause of death and was also an independent predictor. RAS should receive palliative care rather than ICU admission.
Diabetes Mellitus (DM) affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI) and beat-to-beat systolic blood pressure (SBP) variability of patients during ...supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control). A statistically significant distinction between control and diabetic subjects was provided by the standard deviation and the higher moments of the distributions (skewness, and kurtosis) with respect to the median. To compare IBI and SBP for different populations, we define a parameter, α, that combines the variability of the heart rate and the blood pressure, as the ratio of the radius of the moments for IBI and the same radius for SBP. As diabetes evolves, α decreases, standard deviation of the IBI detrended signal diminishes (heart rate signal becomes more "rigid"), skewness with respect to the median approaches zero (signal fluctuations gain symmetry), and kurtosis increases (fluctuations concentrate around the median). Diabetes produces not only a rigid heart rate, but also increases symmetry and has leptokurtic distributions. SBP time series exhibit the most variable behavior for recently diagnosed DM with platykurtic distributions. Under controlled breathing, SBP has symmetric distributions for DM patients, while control subjects have non-zero skewness. This may be due to a progressive decrease of parasympathetic and sympathetic activity to the heart and blood vessels as diabetes evolves.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The objective of the present study was to evaluate the effect of the grade of crossbreeding (Lacaune x Manchega) and environmental factors on milk production in a commercial flock in Spain. A total ...of 5769 milk production records of sheep with different degrees of purity of the Lacaune breed crossed with Manchega were used as follows: 100% Lacaune (
= 2960), 7/8 Lacaune (
= 502), 13/16 Lacaune (
= 306), 3/4 (
= 1288), 5/8 Lacaune (
= 441) and 1/2 Lacaune: Manchega (
= 272). Additional available information included the number of parity (1 to 8), litter size (single or multiple), and the season of the year of lambing (spring, summer, autumn and winter). A mixed model was used to evaluate the level of crossbreeding and environmental factors on milk production. The 100% Lacaune sheep presented the highest milk production with respect to the F1 Lacaune x Manchega sheep (
< 0.01), showing that as the degree of gene absorption increases with the Manchega breed, it presents lower milk yield. The 100%, 13/16, and 3/4 Lacaune genotypes had the highest milk yields with respect to the 1/2 Lacaune/Manchega breed (
< 0.001). The Lacaune registered on average 181.1 L in a period adjusted to 160 days of lactation (1.13 L/ day). Likewise, the parity number, litter size, and season of lambing effects showed significant differences (
< 0.01). It was concluded that 13/16 and 3/4 Lacaune/Manchega ewes presented the highest milk yields with respect to the other crosses.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Helicobacter pylori is the major etiologic agent of such gastric disorders as chronic active gastritis and gastric carcinoma. Over the past few years, the appearance of antibiotic-resistant bacteria ...has led to the development of better treatments, such as the use of natural products. This study evaluated the anti-H. pylori activity of 17 Mexican plants used mainly in the northwestern part of Mexico (Sonora) for the empirical treatment of gastrointestinal disorders. The anti-H. pylori activity of methanolic extracts of the plants was determined by using the broth microdilution method. The 50% minimum inhibitory concentrations ranged from less than 200 to 400 μg/mL for Castella tortuosa, Amphipterygium adstringens, Ibervillea sonorae, Pscalium decompositum, Krameria erecta, Selaginella lepidophylla, Pimpinella anisum, Marrubium vulgare, Ambrosia confertiflora, and Couterea latiflora and were greater than 800 μg/mL for Byophyllum pinnatum, Tecoma stans linnaeus, Kohleria deppena, Jatropha cuneata, Chenopodium ambrosoides, and Taxodium macronatum. Only Equisetum gigantum showed no activity against H. pylori. This study suggests the important role that these plants may have in the treatment of gastrointestinal disorders caused by H. pylori. The findings set the groundwork for further characterization and elucidation of the active compounds responsible for such activity.
Tropical dry forests (TDF) are one of the most widely distributed tropical land‐cover types in Mexico, but their regional‐to‐global contribution to the carbon and water cycles is still highly ...uncertain. We measured CO2 and water vapor fluxes between the ecosystem and atmosphere using the eddy covariance technique from 2016 to 2018 in an old‐growth TDF in northwestern Mexico. First, we investigated the magnitude and seasonality of evapotranspiration (ET), net ecosystem production (NEP) and its contributing fluxes, gross ecosystem production (GEP), and ecosystem respiration (Reco). Second, we explored the main environmental factors controlling carbon and water fluxes as well as tested if this ecosystem acted as a net carbon source or sink. During the study period, all precipitation entering the ecosystem went back to the atmosphere through ET (738.9 ±58.26 mm y−1). Ecosystem respiration (2203.16 ±244.2 g C m−2 y−1) was consistently larger than GEP (1975.32 ±295.52 g C m−2 y−1), determining an annual NEP (−227.6 ±59.4 g C m−2 y−1) that resulted in net annual carbon losses. This forest maintained its water use efficiency (WUE; GEP/ET) across years (2.53–3.24), but water availability constrained light use and maximum carbon assimilation rates. Our results render relevance to the feedback between soil water content and net radiation as the main environmental variables controlling ecosystem fluxes in this old‐growth TDF.
Resumen
El bosque tropical seco (BTS) es una de las coberturas terrestres más ampliamente distribuidas en México, pero su contribución regional y global a los ciclos del carbono y del agua es aún muy incierta. Medimos los flujos de CO2 y vapor de agua entre el ecosistema y la atmósfera utilizando la técnica de covarianza de vórtices entre 2016 y 2018 en un BTS maduro en el noroeste de México. Primero, investigamos la magnitud y la estacionalidad de la evapotranspiración (ET), la producción neta del ecosistema (NEP) y sus flujos contribuyentes, la producción bruta del ecosistema (GEP) y la respiración del ecosistema (Reco). En segundo lugar, exploramos los principales factores ambientales que controlan los flujos de carbono y de agua, y probamos si este ecosistema actuó como fuente o sumidero neto de carbono. Durante el período de estudio, la precipitación que recibió el ecosistema regresó a la atmósfera a través de ET (738.9 ± 58.26 mm y−1). La respiración del ecosistema (2203.16 ± 244.2 g C m−2 y−1) fue consistentemente mayor que la GEP (1,975.32 ± 295.52 g C m−2 y‐1), determinando una NEP anual (−227.6 ± 59.4 g C m−2 y−1) que resultó en pérdidas netas anuales de carbono. Este bosque mantuvo su eficiencia en el uso del agua (WUE; GEP / ET) a lo largo de los años (2.53–3.24), pero la disponibilidad de agua restringió el uso de la luz y las tasas máximas de asimilación de carbono. Nuestros resultados dan relevancia a la retroalimentación entre el contenido de agua del suelo y la radiación neta como las principales variables ambientales que controlan los flujos del ecosistema en este bosque tropical seco maduro.
Plain Language Summary
The contribution of tropical forests to the carbon and water cycles is still uncertain. This is especially true for tropical dry forests with high rainfall seasonality and light availability that may affect their carbon sequestration potential. In this study, we report the results of continuous measurements over a 3 year period of carbon and water fluxes between the atmosphere and a tropical dry forest ecosystem in northwestern Mexico using the eddy covariance technique. We found that the studied old‐growth forest was a net carbon source to the atmosphere across years. This result can be explained by ecosystem respiration (the sum of plant and microbial respiration) since it was constantly larger than the gross ecosystem production (or whole‐ecosystem photosynthesis). The main drivers of carbon and water fluxes were soil water content and net solar radiation, but the relative effect of net solar radiation was strongly dependent on soil moisture. In addition to demonstrating the importance of water and light for controlling whole‐ecosystem processes in seasonally dry tropical forests, our results suggest old‐growth tropical forests with little disturbance can act as carbon sources to the atmosphere. Therefore, further studies should investigate ecosystem fluxes in forests under different disturbance or successional stages.
Key Points
An old‐growth tropical dry forest was a net carbon source regardless of precipitation variability
Carbon and water fluxes were highly seasonal and varied interannually
Main drivers of carbon and water fluxes were soil water content and net solar radiation
Background Small airways disease (SAD), a novel finding described in post-acute COVID-19 patients, should be suspected when respiratory symptoms continue, air trapping persists on expiratory CT ...scans, and imaging findings fail to improve despite objectively better conventional pulmonary function test (PFT) parameters. The forced oscillation technique (FOT) and Multiple breathing washout (MBW) are both very sensitive methods for detecting anomalies in the peripheral airways. Case presentation We discuss the case of a 60-year-old Hispanic patient who had severe COVID-19 pneumonia and developed dyspnea, fatigue, and limited daily activity a year later. The PFTs revealed restrictive lung disease, as seen by significant diffusing capacity of the lungs for carbon monoxide (DLCO) decrease, severe desaturation, and poor 6-min walk test (6MWT) performance. The patient was treated with lowering corticosteroids as well as pulmonary rehabilitation (PR). During the 24-month follow-up, the dyspnea and fatigue persisted. On PFTs, 6MWT performance and restricted pattern improved slightly, but MBW discovered significant ventilatory inhomogeneity. FOT revealed substantial peripheral airway obstructive abnormalities. On CT scans, air trapping and ground-glass opacities (GGO) improved somewhat. The patient used a bronchodilator twice a day and low-dose inhaled corticosteroids (160 microg of budesonide and 4.5 microg of formoterol fumarate dihydrate) for nine months. PR sessions were resuming. The restricting parameters were stabilized and the DLCO had normalized after 36 months, with a 6MWT performance of 87% but significant desaturation. The CT scan revealed traction bronchiectasis, low GGO, and persistent air trapping. Without normalization, FOT and MBW scores improved, indicating small airway disease. Conclusions The necessity of integrating these tests when detecting SAD is emphasized in our paper. This article lays the foundation for future research into the best ways to manage and monitor SAD in post-acute COVID-19 patients. Keywords: COVID-19, Lung Clearance Index, Multiple breathing washout, Oscillometry, Small airway disease
Extreme climatic events are changing the structure and functioning of forests worldwide, and often reducing abruptly their capacity to provide ecosystem services, especially to rural communities ...intimately connected to their environment. In this paper, we analyze climate-induced changes to provisioning ecosystem services, including forest resources available and used by rural communities, and local perceptions about how these services changed after recent extreme climatic events inside and outside a Biosphere Reserve in northwestern Mexico. Our approach integrates quantitative and qualitative techniques from traditional (50 local interviews) and scientific (forest surveys in 24 1-ha plots) ecological knowledge. Our integrated analysis suggests widespread tree mortality was the main ecological effect of recent extreme climatic events, especially in forests regrowing in the reserve former agricultural land, overturning decades of forest natural regeneration. Reserve inhabitants, strongly relying on their surrounding forests for self-consumption, identified climatic events as the main driver of forest change. In addition to climatic events, people outside the reserve recognized selective logging for charcoal production and in general forest exploitation as key drivers of forest change, consistent with the decline of hardwood species revealed by our field surveys. The persistence of an eroding environmental dimension (e.g., unsustainable use of forest resources) outside reserves could increase the long-term vulnerability of rural socioecosystems to extreme climatic events. The protecting role of biosphere reserves will be essential to preserve old-growth forests more resistant to temperature extremes and aid the process of forest natural regeneration after climate-induced disturbance. In order to protect native biodiversity and reduce climate vulnerability, coupled human-environment systems such as Biosphere Reserves should genuinely and rightfully engage local people in management decisions, prioritizing policies that build more sustainable livelihoods and enhance the adaptive capacity of socioecosystems to cope with climate variability.
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