Alternatives to maize monocropping in Mediterranean irrigated conditions to reduce greenhouse gas emissions.

Winter legume cover crops or double-cropping in high N-fertilizer maize-based sprinkler-irrigated systems enhance agroecosystem diversity and potentially increase yields. However, the effects on direct N2O emissions and global warming potential (GWP) have not been fully established. For two years, in the Ebro Valley (Spain), four maize-based systems consisted of: long-season maize (Zea mays) with winter fallow period (F-LSM) the reference system; or after a leguminous cover crop (common vetch, Vicia sativa) (CC-LSM); and short-season maize after a cereal crop (barley, Hordeum vulgare) (B-SSM) or after a leguminous crop (pea, Pisum sativum) (P-SSM). They were assessed in terms of productivity, direct greenhouse gasses emissions (GHG: N2O, CH4, CO2), and global warming potential (GWP). Direct GHG emissions were measured using the static chamber technique, while soil parameters were monitored. Crop yields and nitrogen uptake were also quantified. GHG emissions linked to management and inputs were calculated to obtain GWP and greenhouse gas intensity (GHGI). The most productive system (B-SSM) obtained the highest direct (79 %, 35 %, and 30 % higher than the F-LSM, P-SSM, and CC-SSM, respectively) and scaled N2O emissions. The P-SSM system had similar N-uptake-scaled emissions to the monocropping (MC) systems. Irrigation, fertilizer, and farm operations accounted for the 26 %, 31 %, and 27 % of the total indirect emissions, respectively. Fertilizer production-related emissions in B-SSM and F-LSM systems were 172 % and 45 % higher than the average emissions in the systems with legumes (461 kg CO2eq. ha-1). Diversified systems lead to slightly higher GHGI values than the reference system (F-LSM). However, no differences were found between the F-LSM and P-SSM systems in GWP (4521 and 5512 kg CO2-eq. ha-1, respectively) or GHGI (144 and 158 kg CO2-eq. ha-1, respectively). The P-SSM system may be a potential alternative for increasing the diversification of maize-based irrigated agrosystems without increasing GHG emissions.

Observed humidity trends in dry regions contradict climate models.

Arid and semi-arid regions of the world are particularly vulnerable to greenhouse gas-driven hydroclimate change. Climate models are our primary tool for projecting the future hydroclimate that society in these regions must adapt to, but here, we present a concerning discrepancy between observed and model-based historical hydroclimate trends. Over the arid/semi-arid regions of the world, the predominant signal in all model simulations is an increase in atmospheric water vapor, on average, over the last four decades, in association with the increased water vapor-holding capacity of a warmer atmosphere. In observations, this increase in atmospheric water vapor has not happened, suggesting that the availability of moisture to satisfy the increased atmospheric demand is lower in reality than in models in arid/semi-arid regions. This discrepancy is most clear in locations that are arid/semi-arid year round, but it is also apparent in more humid regions during the most arid months of the year. It indicates a major gap in our understanding and modeling capabilities which could have severe implications for hydroclimate projections, including fire hazard, moving forward.

Pervasive alterations to snow-dominated ecosystem functions under climate change.

Climate change projections consistently demonstrate that warming temperatures and dwindling seasonal snowpack will elicit cascading effects on ecosystem function and water resource availability. Despite this consensus, little is known about potential changes in the variability of ecohydrological conditions, which is also required to inform climate change adaptation and mitigation strategies. Considering potential changes in ecohydrological variability is critical to evaluating the emergence of trends, assessing the likelihood of extreme events such as floods and droughts, and identifying when tipping points may be reached that fundamentally alter ecohydrological function. Using a single-model Large Ensemble with sophisticated terrestrial ecosystem representation, we characterize projected changes in the mean state and variability of ecohydrological processes in historically snow-dominated regions of the Northern Hemisphere. Widespread snowpack reductions, earlier snowmelt timing, longer growing seasons, drier soils, and increased fire risk are projected for this century under a high-emissions scenario. In addition to these changes in the mean state, increased variability in winter snowmelt will increase growing-season water deficits and increase the stochasticity of runoff. Thus, with warming, declining snowpack loses its dependable buffering capacity so that runoff quantity and timing more closely reflect the episodic characteristics of precipitation. This results in a declining predictability of annual runoff from maximum snow water equivalent, which has critical implications for ecosystem stress and water resource management. Our results suggest that there is a strong likelihood of pervasive alterations to ecohydrological function that may be expected with climate change.

Depth Penetration of Light into Skin as a Function of Wavelength from 200 to 1000 nm.

An increase in the use of light-based technology and medical devices has created a demand for informative and accessible data showing the depth that light penetrates into skin and how this varies with wavelength. These data would be particularly beneficial in many areas of medical research and would support the use and development of disease-targeted light-based therapies for specific skin diseases, based on increased understanding of wavelength-dependency of cutaneous penetration effects. We have used Monte Carlo radiative transport (MCRT) to simulate light propagation through a multi-layered skin model for the wavelength range of 200-1000 nm. We further adapted the simulation to compare the effect of direct and diffuse light sources, varying incident angles and stratum corneum thickness. The lateral spread of light in skin was also investigated. As anticipated, we found that the penetration depth of light into skin varies with wavelength in accordance with the optical properties of skin. Penetration depth of ultraviolet radiation was also increased when the stratum corneum was thinner. These observations enhance understanding of the wavelength-dependency and characteristics of light penetration of skin, which has potential for clinical impact regarding optimizing light-based diagnostic and therapeutic approaches for skin disease.

Angiolipoma sacro. Reporte de un caso / Sacral angiolipoma. A case report

Fundamento: Los angiolipomas son tumores benignos que se presentan en adultos con una localización,preferentemente, en el espacio epidural posterior torácico.Objetivo: Presentar un caso que debutó con un traumatismo axial lumbosacro donde se evidenció unalocalización poco común de la lesión y sin relación con las estructuras del canal raquídeo.Presentación del caso: Hombre de 25 años que se cayó y debido a ello se le hizo un traumatismo directo en laregión sacrococcígea con dolor y aumento de volumen regional, asociado a parestesias glúteas. Los estudiosradiológicos evidenciaron una fractura del cóccix y la presencia de una lesión ubicada en las partes blandas, deaspecto redondeado, homogéneo, sólido, de poco más de 50 mm de diámetro. Se le realizó tratamiento quirúrgicoque consistió en coccigectomía subperióstica y exéresis macroscópica de la masa. El estudio histológico concluyóel diagnóstico de un angiolipoma.Conclusiones: Los angiolipomas son tumores raros que tienen características radiológicas peculiares, requierende alta sospecha clínico-imagenológica para indicar los estudios y el tratamiento. La exéresis total esrecomendada para evitar la recurrencia y mejorar el pronóstico. [AU]

Imaging in thick samples, a phased Monte Carlo radiation transfer algorithm.

SIGNIFICANCE: Optical microscopy is characterized by the ability to get high resolution, below 1 µm, high contrast, functional and quantitative images. The use of shaped illumination, such as with lightsheet microscopy, has led to greater three-dimensional isotropic resolution with low phototoxicity. However, in most complex samples and tissues, optical imaging is limited by scattering. Many solutions to this issue have been proposed, from using passive approaches such as Bessel beam illumination to active methods incorporating aberration correction, but making fair comparisons between different approaches has proven to be challenging. AIM: We present a phase-encoded Monte Carlo radiation transfer algorithm (φMC) capable of comparing the merits of different illumination strategies or predicting the performance of an individual approach. APPROACH: We show that φMC is capable of modeling interference phenomena such as Gaussian or Bessel beams and compare the model with experiment. RESULTS: Using this verified model, we show that, for a sample with homogeneously distributed scatterers, there is no inherent advantage to illuminating a sample with a conical wave (Bessel beam) instead of a spherical wave (Gaussian beam), except for maintaining a greater depth of focus. CONCLUSION: φMC is adaptable to any illumination geometry, sample property, or beam type (such as fractal or layered scatterer distribution) and as such provides a powerful predictive tool for optical imaging in thick samples.

Development of a Predictive Monte Carlo Radiative Transfer Model for Ablative Fractional Skin Lasers.

It is possible to enhance topical drug delivery by pretreatment of the skin with ablative fractional lasers (AFLs). However, the parameters to use for a given AFL to achieve the desired depth of ablation or the desired therapeutic or cosmetic outcome are hard to predict. This leaves open the real possibility of overapplication or underapplication of laser energy to the skin. In this study, we developed a numerical model consisting of a Monte Carlo radiative transfer (MCRT) code coupled to a heat transfer and tissue damage algorithm. The simulation is designed to predict the depth effects of AFL on the skin, verified with in vitro experiments in porcine skin via optical coherence tomography (OCT) imaging. Ex vivo porcine skin is irradiated with increasing energies (50-400 mJ/pixel) from a CO2 AFL. The depth of microscopic treatment zones is measured and compared with our numerical model. The data from the OCT images and MCRT model complement each other well. Nonablative thermal effects on surrounding tissue are also discussed. This model, therefore, provides an initial step toward a predictive determination of the effects of AFL on the skin. Lasers Surg. Med. © 2020 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC.

Obstetric anal sphicnter injury in a Spanish hospital.

OBJECTIVE: Estimation of the prevalence of obstetric anal sphincter injury (OASIS) in our environment and study of the associated risk factors. STUDY DESING: A retrospective observational study of cases and controls of assisted deliveries at the Severo Ochoa University Hospital of Leganés during the period from January 1, 2012, to December 31, 2017. A total of 88 OASIS diagnosed in the study period is compared with a randomly selected group of 181 controls of similar characteristics, vaginal births of cephalic of 36 weeks gestation or more, occurring during the same period. RESULTS: During the study period, a total of 8160 deliveries were attended in our hospital, of which 6187 were vaginal and we diagnosed a total of 88 OASIS at the time of delivery. The prevalence of OASIS is 1.07 % for total births and 1.42 % for total vaginal deliveries. In the case-control study, the univariate analysis shows statistical significance for nulliparity (OR 3.84; 95 % CI 2.155-6.834; p < 0.001), instrumental delivery (OR 8.73; 95 % CI 4.706-16.2016; p < 0.001), occipital posterior position (OR 7.23; 95 % CI 2.535-20.633; p < 0.001), long duration of the second stage of labor (OR 1.99; IC95 % 1,159-3,438; p 0.01), episiotomy (OR 3.51; 95 % CI 1,956-6,309; p < 0.001) and OBGYN labor assistant (<0.001). When performing the multivariate analysis, forceps delivery (OR19.68), Thierry spatulas delivery (OR 8.15), vacuum delivery (OR 2.74), nulliparity (OR 2.56) and fetal weight in grams (OR 1.12) remain significant in the final model. CONCLUSION: The main risk factors for the onset of OASIS are instrumental delivery, nulliparity and fetal birth weight.

A stratospheric pathway linking a colder Siberia to Barents-Kara Sea sea ice loss.

Previous studies have extensively investigated the impact of Arctic sea ice anomalies on the midlatitude circulation and associated surface climate in winter. However, there is an ongoing scientific debate regarding whether and how sea ice retreat results in the observed cold anomaly over the adjacent continents. We present a robust "cold Siberia" pattern in the winter following sea ice loss over the Barents-Kara seas in late autumn in an advanced atmospheric general circulation model, with a well-resolved stratosphere. Additional targeted experiments reveal that the stratospheric response to sea ice forcing is crucial in the development of cold conditions over Siberia, indicating the dominant role of the stratospheric pathway compared with the direct response within the troposphere. In particular, the downward influence of the stratospheric circulation anomaly significantly intensifies the ridge near the Ural Mountains and the trough over East Asia. The persistently intensified ridge and trough favor more frequent cold air outbreaks and colder winters over Siberia. This finding has important implications for improving seasonal climate prediction of midlatitude cold events. The results also suggest that the model performance in representing the stratosphere-troposphere coupling could be an important source of the discrepancy between recent studies.

Transition between paraxial and Helmholtz Fourier spaces.

Different correction methods for paraxial solutions have been used when such solutions extend out of the paraxial regime. Mapping functions play a fundamental role in them. This paper analyzes how to translate directions of paraxial wavevectors into Helmholtz wavevectors. Two possible mappings that are commonly used are examined, and a new mapping is proposed. The three mappings are classified in the framework of the full wave correction schemes.

Angular spectral framework to test full corrections of paraxial solutions: erratum.

In our previous article [J. Opt. Soc. Am. A32, 1236 (2015)JOAOD60740-323210.1364/JOSAA.32.001236] there is an issue concerning the comparison of plane wave spectrum solutions of paraxial and Helmholtz equations. We compared the angular plane wave spectrum of Helmholtz solutions with the plane wave spectrum of the paraxial solutions in terms of normalized projections of paraxial wave vectors. We show that the proper comparison of plane wave spectra must be done in terms of angles. The results presented in our previous work are corrected accordingly. The most important change is that Wünsche's T2 operator leads to a valid method.

Angular spectral framework to test full corrections of paraxial solutions.

Different correction methods for paraxial solutions have been used when such solutions extend out of the paraxial regime. The authors have used correction methods guided by either their experience or some educated hypothesis pertinent to the particular problem that they were tackling. This article provides a framework so as to classify full wave correction schemes. Thus, for a given solution of the paraxial wave equation, we can select the best correction scheme of those available. Some common correction methods are considered and evaluated under the proposed scope. Another remarkable contribution is obtained by giving the necessary conditions that two solutions of the Helmholtz equation must accomplish to accept a common solution of the parabolic wave equation as a paraxial approximation of both solutions.

Transition between free-space Helmholtz equation solutions with plane sources and parabolic wave equation solutions.

The slowly varying envelope approximation is applied to the radiation problems of the Helmholtz equation with a planar single-layer and dipolar sources. The analyses of such problems provide procedures to recover solutions of the Helmholtz equation based on the evaluation of solutions of the parabolic wave equation at a given plane. Furthermore, the conditions that must be fulfilled to apply each procedure are also discussed. The relations to previous work are given as well.

Applying human factors to the design of medical equipment: patient-controlled analgesia.

OBJECTIVE: Medical instruments commonly have poorly designed user interfaces that promote human errors with life-threatening consequences. The primary hypothesis of this study was that a specific user interface could be made safer and more efficient if redesigned using human factors techniques and principles. METHODS: The user interface of a commercially available patient-controlled analgesia (PCA) pump, the Abbott Lifecare 4100 PCA Plus II infuser, was evaluated using a cognitive task analysis of bench tests and field observations. Based on this analysis, the user interface was redesigned. Important elements of the new design include a dialog structure with fewer steps, a dialog overview showing the user's location in the programming sequence, better command feedback, easier error recovery, and clearer labels and messages. The changes were evaluated by comparing a computer prototype of the new interface with a computer simulation of the old one. Twelve student nurses performed six programming tasks with each interface. Task completion time, number of errors, and subjective mental workload were collected for each trial. RESULTS: The results showed significantly faster programming times (F(1,11) = 6.85, P < 0.025), lower mental workload ratings (chi2(1) = 4.45, p < 0.025, one-tailed), and fewer errors (chi2(1) = 3.33, p < 0.05, one-tailed) with the new interface. CONCLUSION: Adopting a human factors approach to redesigning the PCA interface led to significantly faster, easier, and more reliable performance. These findings have important implications for improving the design of other computer-based medical equipment.