Search

Aquifer karstic structures, due to their complex nature, present significant challenges in accurately mapping their intricate features. Traditional methods often rely on invasive techniques or sophisticated equipment, limiting accessibility and feasibility. In this paper, a new approach is proposed for a non-invasive, low-cost 3D reconstruction using a camera that observes the light projection of a simple diving lamp. The method capitalizes on the principles of structured light, leveraging the projection of light contours onto the karstic surfaces. By capturing the resultant light patterns with a camera, three-dimensional representations of the structures are reconstructed. The simplicity and portability of the equipment required make this method highly versatile, enabling deployment in diverse underwater environments. This approach is validated through extensive field experiments conducted in various aquifer karstic settings. The results demonstrate the efficacy of this method in accurately delineating intricate karstic features with remarkable detail and resolution. Furthermore, the non-destructive nature of this technique minimizes disturbance to delicate aquatic ecosystems while providing valuable insights into the subterranean landscape. This innovative methodology not only offers a cost-effective and non-invasive means of mapping aquifer karstic structures but also opens avenues for comprehensive environmental monitoring and resource management. Its potential applications span hydrogeological studies, environmental conservation efforts, and sustainable water resource management practices in karstic terrains worldwide. [ABSTRACT FROM AUTHOR]

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic neoplasm (less than 1% of primary cutaneous lymphomas and acute leukemia) with a highly aggressive clinical course and frequent skin, bone marrow and central nervous system involvement. Even though there is often an early response to chemotherapy, leukemic dissemination relapses are very common and result in poor outcomes, with a median overall survival of 8 to 14 months in the first-line setting using standard combination chemotherapy regimens. Almost 90% of patients experience skin involvement as their initial site of infection, where BPDCN may stay restricted for weeks or even months until a swift secondary phase involving multiple organs takes place. Consequently, it is crucial to suspect and identify early skin lesions, as well as to conduct and report a skin biopsy as soon as possible. In order to diagnose and treat BPDCN, a multidisciplinary strategy involving collaboration between pathologists, hematologists, and dermatologists is unquestionably essential. [ABSTRACT FROM AUTHOR]

The Bengal tiger (Panthera tigris tigris) is a species belonging to the Felidae family. In Argentina, tigers are currently only found in captivity. The longevity of individual animals in human‐controlled environments depends on proper management and practices that prioritize animal welfare. Regular veterinary care is essential to maintain optimal health conditions. Professionals must have a comprehensive understanding of the anatomy and physiology of tigers to effectively perform medical procedures and administer treatments. The study described in the text focuses on the trajectory and distribution of nerves in the pelvic limb of a Bengal tiger specimen, providing detailed dissection findings. The results revealed that the lumbosacral plexus is formed from the ventral rami of the LIV, LV, LVI, LVII, SI, SII and SIII nerves. Among the observations to highlight is the great development of the nerves N. cutaneus femoris lateralis and N. cutaneus femoris caudalis some differences were observed in the distribution of the N. femoralis and N. obturatorius; the N. ischiadicus, together with its division into the fibularis communis and tibialis nerves, showed the same configuration observed in other cats. Finally, it was observed that the nerves N. gluteus cranialis and N. gluteus caudalis also originated from the truncus lumbosacralis. The similarities and differences with studies carried out on other cats are relevant and provide anatomical data for medical procedures in the Bengal tiger. [ABSTRACT FROM AUTHOR]

Here, we present a set of algorithms using the Python programming language, that will allow using a routine for object detection and tracking in experimental videos. We developed a script, under the fundamentals of background subtraction and image thresholding (using the OpenCV package), that makes it possible to track a wide spectrum of animals under different conditions. We have validated this script through testing on semi-terrestrial and aquatic crustacean species and under different experimental scenarios (laboratory and field sampling and using video created under nocturnal and diurnal conditions). The open-source nature of the script allows for flexibility and scalability, so it can be easily customized and is thus transferable to other species/experiments in the context of behavioral ecology. The tracking script is easy customizable and free alternative to commercial video tracking systems and therefore, applicable to a wide variety of both educational and research programs. [ABSTRACT FROM AUTHOR]

The association of roots with mycorrhizal fungi increases the establishment success of forest species. Cordilleran cypress naturally forms associations with arbuscular mycorrhizae (AM). In general, the use of fertigation and artificial growth methods causes a decrease in mycorrhization, which could lead to a decrease in seedling performance in the field. The objectives of this study were: to determine whether AM colonization occurs in a nursery; to evaluate the influence of differing availability of phosphorus and substrate water status on the level of mycorrhizal colonization during plant growth; and to analyze the abundance of mycorrhization and its relationship with post-planting survival. The trial treatments were only applied during plant growth and consisted of a combination of three phosphorus concentration levels (1, 10 and 100 mg L-1) and two substrate water statuses (20 and 80 % of the container capacity (Cc)). The percentage of mycorrhization (% AM) was evaluated in plants grown in a nursery, in a sterilized substrate in the field, as was its survival in the field. Among the most relevant results, 24 % AM was found in the nursery while this value increased in the field (93 %), indicating that the mycorrhizal colonization process occurs during plant growth, even though it is partially inhibited by phosphorus and water management. It was also observed that the % MA increased once the plant was taken to the field independently of the % MA of the seedling in the nursery. [ABSTRACT FROM AUTHOR]

As today the 137Cs fallout peak, in sediment cores, corresponds only to 25% of its initial concentration, alternatives to the use of 137Cs as a210Pb sediment dating validation tool are proposed. In highly industrialized bays, such as Guanabara Bay in the Rio de Janeiro metropolitan region, several chemical/compounds from the surrounding industry releases may be applied as validation tools. Chromium and copper profiles in a sediment core adequately fit the expected pattern due to the implementation of a chemical plant in 1958, reaching their maximum discharge in 1982 and subsequently decreasing due to the operation of a new wastewater treatment plant. A diffuse source such, as the PCB-based mixture Askarel, was also applied as an alternative validation tool, and the observed concentration profile reproduced the expected behavior, with increasing concentration after the Second World War and a decrease after the ban of this product in 1981. The observed Aroclor 1254 and 1260 mixture chlorination rates fit the most widely distributed PCB-based products in the country. • Alternatives for 210Pb sediment dating validation are suggested. • Chromium and zinc profile reflected the changes on a chemical industry. • PCB profile was compatible with the historical Askarel application in Brazil. [ABSTRACT FROM AUTHOR]

Therefore, hospitals needed to combine prevention of in-hospital SARS-CoV-2 spread and maintenance of standard of care for non-SARS-CoV-2 patients. Managing a SARS-CoV-2-free Hospital Unit of Internal Medicine to avoid in-hospital clusters Keywords: cluster; hospital; SARS-CoV-2 EN cluster hospital SARS-CoV-2 1 4 4 03/11/22 20220401 NES 220401 Besides its terrible claim in terms of human lives, SARS-CoV-2 pandemic hit hard also on the hospital management with most healthcare facilities being overwhelmed by hundreds of patients with SARS-CoV-2-related symptoms. [Extracted from the article]

Long-term ecological data is essential to identify impacts of global change or to analyse the response of local systems to perturbations. Thus, ecologists are facing the compromise to collect and process longer-term data while specific funding for those purposes is extremely scarce. Although more funding to gather and store long term data would be ideal, it is unlikely to occur, at least in the short term. Another (most plausible) option could be to dive among the many spreadsheets belonging to one or more colleagues with shared variables and from several projects over the years. Obviously, this might be an extremely time-consuming and tedious task. To simplify this and save time, it would be ideal to store as much data as possible (individual or lab generated) in a single comprehensive database. Given that the process of building, maintaining and doing queries on such databases could be scary for ecologists not familiarized, here we provide a step-by-step guide to build 1) a generic and versatile ecological database, and 2) a graphical user interface to load, update, verify, view and download data. The scripts to build them are programmed on open-software (MariaDB and R), and we also provide instructions to change them according to many usual situations. [ABSTRACT FROM AUTHOR]

A main scientific and technical challenge facing the implementation of new and sustainable energy sources is the development and improvement of materials and components. In order to provide commercial viability of these applications, an intensive research in material-hydrogen (H) interaction is required. This work provides an overview of recently developed in-situ and in-operando H-charging methods and their applicability to investigate mechanical properties, H-absorption characteristics and H embrittlement (HE) susceptibility of a wide range of materials employed in H-related technologies, such as subsea oil and gas applications, nuclear fusion and fuel cells. • In-situ and in-operando methods were reviewed for studying material-H interaction. • Fundamental models of the H charging mechanisms are discussed. • Potential benefits for small scale testing for energy related material development. [ABSTRACT FROM AUTHOR]

Three medium-carbon, high-silicon cast steels with different alloy contents were austempered at 330 °C for different holding times in order to obtain carbide-free bainitic microstructures. Aiming at evaluating the influence of holding time and microstructural features on strength and ductility, tensile properties were measured for each steel at selected austempering times. The results obtained indicate that it is possible to adjust holding time in order to obtain the best strength/ductility combination at determined austempering temperature. Moreover, it has been shown that the mechanical stability of retained austenite is the key factor in controlling tensile performance. Short austempering times result in low carbon enrichment of the austenite (low stability) and promote higher ultimate tensile strength and lower ductility. For longer austempering times, steels present a slight decrease in ultimate tensile strength but a marked increase in ductility. This work shows that it is possible to obtain cast steels with ultimate tensile strength of 1682 MPa, yield strength of 1493 MPa and total elongation of 12.5% by means of bainitic reaction. This strength/ductility combination and others reported in this study are remarkable for cast steels. [ABSTRACT FROM AUTHOR]

The term non-melanoma skin cancer (NMSC) refers to skin cancer different from melanoma, and it is usually restricted to basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and their pre-cancerous lesions, e.g., actinic keratosis. These conditions represent the most frequent tumors in Caucasians and are characterized by an increasing incidence worldwide and a high socio-economic impact. The term Integrated Care Pathway (ICP) refers to "a complex intervention for the mutual decision making and organization of care processes for a well-defined group of patients during a well-defined period". The purpose of this paper is to present a proposal from the Italian Association of Hospital Dermatologists (ADOI) for an ICP organization of care of NMSC, considering the hub-and-spoke model in the different geographical areas. This proposal is based on the most recent literature and on documents from the Italian Association of Medical Oncology (AIOM), the European consensus-based interdisciplinary guidelines from the European Association of Dermato-Oncology (EADO), and the National Comprehensive Cancer Network (NCCN). We initially discuss the NMSC outpatient clinic, the role of the multidisciplinary working groups, and the hub-and-spoke model regarding this topic. Then, we define the ICP processes specific for BCC and SCC. The ICP for NMSC is an innovative strategy to guarantee the highest possible quality of health care while the hub-andspoke model is crucial for the organization of different health care structures. Considering the importance on this topic, it is essential to create a valid ICP together with an efficient organization within the different geographical areas. [ABSTRACT FROM AUTHOR]

This work is focused on the study of the columnar-to-equiaxed transition in free graphite cast irons and the correlation of this phenomena with the temperature gradients during solidification. Samples of lamellar, compacted and spheroidal graphite irons were cast and their solidification macrostructures were revealed by application of the direct austempering after solidification technique. All the samples presented a sharp columnar-to-equiaxed transition and the determination of its location was carried out by visually inspecting each of the macrostructures obtained. In addition, computational simulations of filling and solidification of the castings were carried out to calculate the temperature gradient profiles along the whole volume of the casting samples. The comparison of experimental and numerical results showed that there is a critical temperature gradient value defining the columnar-to-equiaxed transition for all the free graphite cast irons samples analyzed in this work, regardless of their graphite morphology and casting geometry. [ABSTRACT FROM AUTHOR]

Because of the coronavirus disease 2019 (COVID‐19) emergency, on March 9, 2020 Italy went in lock‐down imposing the closure of non‐urgent outpatient clinics devoted to care of chronic, severe, inflammatory skin diseases that require periodic follow‐up. In this emergency situation, due to the lack of a teledermatology platform and in order not to leave our vulnerable high‐need patients without proper follow‐up, we started a teledermatologic service in smartworking using phone calls and emails. The total number of patients scheduled was 195; in 12 cases, we were not able to talk to the patients. Remote monitoring was performed in 183 patients (126 moderate to severe psoriasis, 10 severe acne, 11 severe atopic dermatitis, 11 hidradenitis suppurativa, 9 blistering autoimmune diseases, and 16 other autoimmune skin diseases). During remote‐visits, several interventions were conducted: triage for COVID‐19 suspected symptoms, email check of clinical pictures and of laboratory examinations, advices for topical and systemic therapy continuation or discontinuation/switch and reschedule of next appointment. Only five patients required personal office visit (2.7%), reducing consistently the number of face‐to face visits. Our real‐life experience shows that remote monitoring was effective in preventing unnecessary worsening of severe chronic skin diseases and poor outcomes due to withdrawal of current therapy. [ABSTRACT FROM AUTHOR]

There is a current discussion concerning the austenite grains of lamellar graphite irons and its growth at different carbon equivalent contents. The term "grain" is often employed to refer not only to the primary austenite, but also to the colonies or cells formed during the eutectic solidification. This investigation applies advanced experimental methods to study the solidification of lamellar graphite iron. A better understanding of the solidification process should lead to the design of better casting procedures. Samples of lamellar graphite iron were cast and directly austempered after solidification in order to reveal their solidification macrostructure. A typical ingot structure was found, with a narrow columnar-to-equiaxed transition. Electron backscatter diffraction technique was applied to confirm these macroscopic observations. Color etching was employed to determine the size of eutectic colonies at the columnar and equiaxed regions. The EBSD results confirm previous proposals, revealing that the solidification grains result from the growth of austenite dendrites. These grains include several eutectic colonies or cells inside, all these colonies or cells having the same crystalline orientation as the primary austenite dendrite. An analysis of the critical gradient for columnar-to-equiaxed transition could be developed. The size of the eutectic colonies at the columnar zone was found to be smaller than the size of the eutectic colonies at the equiaxed zone. Besides, the size of equiaxed grains strongly decreased with the increase in cooling rate, while no evident differences were obtained when the size of the columnar grains was measured. [ABSTRACT FROM AUTHOR]

An in situ hydrogen (H) plasma charging and in situ observation method was developed to continuously charge materials, while tensile testing them inside a scanning electron microscope (SEM). The present work will introduce and validate the setup and showcase an application allowing high-resolution observation of H-material interactions in a Ni-based alloy, Alloy 718. The effect of charging time and pre-straining was investigated. Fracture surface observation showed the expected ductile microvoid coalescence behavior in the uncharged samples, while the charged ones displayed brittle intergranular and quasi-cleavage failure. With the in situ images, it was possible to monitor the sample deformation and correlate the different crack propagation rates with the load-elongation curves. H-charging reduced the material ductility, while increasing pre-strain decreased hydrogen embrittlement susceptibility due to the possible suppression of mechanical twinning during the tensile test and, therefore, a reduction in H concentration at grain and twin boundaries. All the presented results demonstrated the validity of the method and the possibility of in situ continuously charging of materials with H without presenting any technical risk for the SEM. [ABSTRACT FROM AUTHOR]

Cutaneous papillomas (CP) are one of the most common skin neoplasms in dogs. Different murine models have shown that persistent activation of the phosphatidylinositol 3‐kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway has a central role in the development and progression of CP. The purpose of this study were to evaluate the immunohistochemical expression pattern of two key molecules involved in the PI3K/Akt/mTOR signalling pathway, pAktSer473, and pS6Ser235/236, on 36 canine specimens of CP using a tissue microarray. The results show that the PI3K/Akt/mTOR signalling pathway is persistently activated in CP of dogs, pointing to this pathway as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Slender RC walls are often used in Chile and commonly, due to architectural constraint, the length of walls increases (setback) between floors designated for parking space and upper floors. These types of elements are commonly called flag walls. In this research, the behavior of slender reinforced concrete walls with a constant axial load and a cyclic lateral displacement is numerically studied, in order to compare the results obtained with previous tests. Two different model alternatives are considered: a finite element model and a strut-and-tie model. The selected models allow understanding local response, as well as, distribution of internal forces, which is also relevant information for wall design and detailing. The studied finite element model, based on quadrilateral elements with 3 degrees of freedom per node (2 translational and 1 rotation) and a model of smeared reinforced concrete material based on a rotating angle approach, is able to correctly capture the global response, showing the capacity, degradation and failure mode obtained in the tests. On the other hand, a parametric analysis is performed for models of walls with higher aspect ratio (tall buildings) with small discontinuities, showing a larger impact in deformation capacity due to the high concentration of damage at the discontinuity. These results indicate that in 25-floor high walls (or taller) a reduction of displacement capacity of 40% for discontinuities located at the first floor could be observed. In addition, by incorporating the effect of the slabs into the model, the results indicate that a pure flexure model is an adequate and sufficient tool for analysis. Finally, a strut-and-tie model is also proposed for each direction of the lateral load, whose results are compared with the estimated load calculated with the strains measured by photogrammetry. The considered strut-and-tie model for the case of lateral load with tension in the continuous wall boundary is similar to the wall without discontinuity, which is consistent with the measured strains. For both lateral loading directions, the estimated forces of the horizontally distributed bars and boundary reinforcements are consistent with photogrammetry in the lower zone of the wall, where cracking is relevant. The strut-and-tie model also adequately interprets the effect of the discontinuous bar on the discontinuous boundary of the wall. All these results can help designing and detailing flag walls. [ABSTRACT FROM AUTHOR]

This article discusses the multidisciplinary approach in the management of primary cutaneous lymphomas (PCLs). PCLs are a diverse group of neoplastic diseases that require a multidisciplinary approach for effective management. The classification of PCLs has been revised over the years, and new therapies have become available. The article summarizes lectures delivered at a conference on PCLs, with the aim of presenting the latest advancements in the field and increasing awareness among dermatologists, pathologists, and hematologists. The authors hope that this monograph will contribute to early and accurate diagnoses and improve patient treatment. [Extracted from the article]

Total body computed tomography (CT) scan and positron emission tomography (PET) revealed only a paratracheal lesion consistent with BPNCD. Dear Editor, A 63-year old man presented in May 2019; for 3 weeks, he complained of a slowly enlarging asymptomatic lesion on his left chest. [Extracted from the article]

Demand for alternative sources of energy has grown steadily on the world stage. And the concept of sustainability appears in full force to reduce the environmental degradation generated by this great energy consumption. In this sense, energy harvesting plays a predominant role in this scenario. Energy harvesting is the process by which energy from external sources such as solar, wind, vibrational, and others can be transformed into electrical energy. The kinetic energy that machines or organisms make available to the environment is called vibrational energy and can be transformed into electrical energy from piezoelectric materials. The objective of this paper is to present the process of vibrational energy harvesting and the main challenges for useful energy generation. Studies will be presented in the area containing nonlinearities and chaos in the power generator system from piezoelectric materials. These nonlinearities may be embedded in the material rigidity, electrical circuit coupling and the electrical circuit itself. The base excitation of the system can be harmonic, random and harmonic-random. [ABSTRACT FROM AUTHOR]

Highlights • Selected molecules of the mammalian target of rapamycin (mTOR) pathway have a low expression in the normal canine epidermis. • The key proteins involved in the mTOR pathway are dysregulated during epidermal carcinogenesis in dogs. • These findings point to the mTOR pathway as a potential therapeutic target in canine cutaneous squamous cell carcinomas. Abstract Cutaneous squamous cell carcinoma (cSCC) represents one of the most common malignant skin tumors in dogs. Research aimed at clarifying how the deregulated activity of signalling pathways contributes to cSCC progression can help to identify molecular suitable targets for the development of novel therapies. The present study describes the immunohistochemical expression pattern of two proteins (pAktSer473 and pS6Ser235/236, the latter combined with Ki-67) involved in the phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signalling pathway in canine specimens of normal epidermis, pre-neoplastic epidermis, and cSCC using tissue microarrays. The results suggest that the PI3K/Akt/mTOR signalling pathway has a low expression in the normal canine epidermis, and that selected molecules involved in this signalling pathway are dysregulated during the canine epidermal carcinogenesis process. These findings provide important evidence that the persistent activation of the PI3K/Akt/mTOR signalling pathway represents one of the key events during cSCC progression in canine patients, pointing to the PI3K/Akt/mTOR pathway as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Abstract This work studies the surface characteristics and, particularly, the rolling contact fatigue (RCF) behavior of austempered ductile iron (ADI) samples coated with TiN based coatings of about 1 μm in thickness. Films synthesized by cathodic arc deposition (CAD) at a fixed nitrogen flow, compositional gradient films synthesized by CAD at a variable nitrogen flow and plasma based ion implanted and deposited (PBIID) films were comparatively analyzed. The results indicated that CAD films showed a strong TiN (111) preferred orientation while PBIID films a more randomly orientation. The crystallite size of CAD films was more than the double of PBIID films. Residual stresses of the PBIID films were lower than those of CAD films, the lowest hardness and elastic modulus were obtained for CAD films grown at variable nitrogen flow, while no significant differences in roughness, H/E ratio and adhesion were observed among the different films. Regarding RCF tests, failures in samples coated with TiN at constant flow were characterized by a progressive coating delamination followed by the formation of fatigue spalls inside the delaminated areas. Failures in samples coated with PBIID and gradient TiN were characterized by the formation of fatigue spalls with slight coating delamination. There were no significant differences between the RCF resistance of uncoated ADI and the samples with CAD films while the samples with PBIID films had a noticeably higher resistance. The better performance could be associated with the low compressive residual stresses and the fine grained microstructure induced by the PBIID process. Highlights • Cathodic arc deposited (CAD) films synthesized at variable and constant nitrogen flows. • Constant-flow CAD films delaminated during rolling contact fatigue (RCF) tests. • Neither variable-flow CAD nor ion-implanted/deposited films delaminated during RCF tests. • RCF behavior of austempered ductile iron was not modified by CAD. • RCF endurance of austempered ductile iron increased by ion-implanted/deposited films. [ABSTRACT FROM AUTHOR]

Highlights • A new passive decay heat removal system has been invented for molten salt reactor emergency draining tank system. • This system is based on the loop heat pipe concept. • It includes an evaporating tank (emergency draining tank), and where the liquid fuel is mixed with a working fluid (sodium) and to vaporizes the working fluid. • The resulting vapor pressure drives the vapor through the pipes to the condensers, where the vapor condenses, releasing its latent heat of vaporization to a provided heat sink. • The condensers are located above the emergency draining tank at a higher elevation than the vaporization tank, so the condensed working fluid can flow back to the emergency draining tank by gravitational force. • Therefore, the system can continuously and passively transport the latent heat of vaporization from the emergency draining tank to the condenser section. Abstract A passive decay heat removal system is proposed that is actuated by the phase change heat transfer method (latent heat of fusion and evaporation) for an emergency draining tank system of molten salt reactors. The emergency draining tank serves an evaporating tank, where the liquid fuel is mixed with an immiscible working fluid and later to vaporize this working fluid. The top header of the vaporizing tank is connected by pipes to a condenser. The resulting vapor pressure of the working fluid drives the vapor through these pipes to condensers, The condensers are located above the reactor, where the vapor condenses, releasing its latent heat of vaporization to a provided heat sink (air heat exchanger). The condensed working fluid flows at first in a Pythagorean cup type collector, which is located just below the condensers, the collected working fluid flows back, in batch, to the emergency draining tank by gravitational force. In this batch manner the working fluid can be strongly mixed with the liquid fuel to enhance the heat transfer between liquid fuel and working fluid without any mechanical or electrical assistance, i.e. a completely passive heat removal process. Therefore the system can passively transport the latent heat of vaporization of the working fluid from the emergency draining tank to the condenser section. This proposed decay heat removal system is described in more detail in this paper. The passive cooling of the liquid fuel to extract the residual heat has been studied. [ABSTRACT FROM AUTHOR]

Highlights • Walls with opening present less displacement capacity. • Limit compressive strain can provide safe design of walls with openings. • Flexural model can predict response of walls with openings. • Slabs improve displacement capacity of walls with openings. Abstract According to Chilean design practice, walls usually have complex geometries and discontinuities in height, mainly in the first story. However, the Chilean design code, similar to many design codes, does not provide special provisions for discontinuities. This paper shows the results of an experimental and numerical study of walls with a central opening at the base. Four slender walls are constructed with the same general dimensions, but with different shapes of the opening (15% and 30% of the length, and 11% and 22% of the wall height). The specimens were tested under constant axial load, while cyclic lateral loading is applied at the top. One of the specimens presents slab elements at the base. Results indicate that lateral strength is similar in all cases; however, displacement capacity varies with opening size. All specimens with openings have less ductility, where the specimen with wider and taller opening had a reduced displacement capacity (∼30% reduction). The width of the opening was more influential than the height in the displacement capacity. Numerical analysis was done through a finite element modeling, where one of the models considered all features of the formulation and a second model considered rigid beams placed in all levels forcing the Bernoulli hypothesis (flexural model). Both models can capture strength, stiffness and displacement capacity, and therefore a flexural model can be used for boundary detailing. [ABSTRACT FROM AUTHOR]

Highlights • Walls with setback present damage localization. • Plastic hinge is bounded by the setback. • Continuous wall side presents tensile strain distribution consistent with rectangular wall. • Reinforcing longitudinal bars need proper anchorage in discontinuous locations. Abstract After the 2010 Maule, Chile, earthquake (Mw 8.8), several reinforced concrete (RC) buildings presented damage in some walls (crushing of concrete, buckling and fracture of steel reinforcement). These buildings had been designed according to the up-to-date seismic standards in the country and were not expected to suffer damage as severe as what was observed. Common features of the damaged walls were: little or no confinement at the wall ends; relatively high axial load; narrow thicknesses (below 200 mm); and discontinuities in height. Slender RC walls are often used in Chile and commonly, due to architectural constraints, the length of the walls changes between floors designated for parking use and the upper floors, creating a setback in the lower levels. These types of walls are commonly called "flag walls". The problem of discontinuity has not been investigated experimentally and therefore it is necessary to observe its impact in RC walls. Four structural wall specimens were designed, one with no discontinuity and the other three with different sizes of the setback. They were tested under a nominal constant axial load of 0.1f'cAg and cyclic lateral loads increasing at specific drift levels. Conventional instrumentation and photogrammetry were used to monitor the tests. The experimental results show that the impact of the setback, for the sizes tested, is not significant for the strength but it is relevant for the strength degradation and deformation capacity. Strains in the extreme fibers, curvature and principal strains are studied using photogrammetry. It is found that the plastic hinge length increases with drift, but it remains constrained to the setback region. Another discontinuity is found around the reinforcement of the setback where large concentration of strains can cause premature failure of the wall. [ABSTRACT FROM AUTHOR]

This research develops a 3D macroscopic model to capture the shear and flexural behavior of square and rectangular reinforced concrete columns under biaxial lateral loads. This efficient-shear-flexure-interaction (E-SFI)–BIAXIAL model, based on the E-SFI two-dimensional macro model, reformulates the materials and elements to a 3D domain. Reinforced concrete prisms with three-dimensional behavior are incorporated using a rotating-angle approach and calibrated expression of the two-dimensional model to calculate the horizontal strain in each orthogonal direction (ɛ x and ɛ z). This approach reduces the number of iterative processes and analysis time. Model validation employed an extensive database of 56 reinforced concrete column tests with shear failure under cyclic biaxial loading conditions, 41 square and 15 rectangular, as reported in the literature. The validation demonstrated that the model accurately captures the hysteretic response and shear failure mode of the tests. The results are verified against the experimental data regarding the load–displacement response and the contribution of flexural and shear displacements. The model's estimated shear strength agreed well with experimental data, with average ratios of measured to calculated maximum shear strength of 0.91 and 0.95 for square and rectangular columns with coefficients of variation of 0.078 and 0.12, respectively. The onset of strength degradation was also compared, achieving average ratios of the measured to calculated drift for square and rectangular columns of 1.02 in both cases, with coefficients of variation of 0.32 and 0.4, respectively. Furthermore, the normalized biaxial shear strength results from the experimental tests and the model fit the circular interaction curve and validate the proposed ACI 318-19 code provisions to capture the biaxial shear effect through a trilinear curve. • Shear strength of square and rectangular RC columns under biaxial lateral loads. • Nonlinear and coupled shear–flexure analytical response of square and rectangular RC columns. • Evaluation of the ACI 318-19 proposal to consider simultaneous lateral loads. • Nonlinear model for RC columns with a 3D material and element. [ABSTRACT FROM AUTHOR]

A model capable of predicting the shear response of beam-column joints subjected to seismic actions is presented. The analytical model, originally developed for walls and based on a simple physical formulation, is adapted. It considers mean stress and strain fields based on a reinforced concrete panel representing the joint, under the assumption that the principal concrete stress and principal strain directions coincide. Simple constitutive material laws are considered for concrete and steel. To estimate the shear capacity, the model satisfies the equilibrium in the longitudinal (vertical) direction. In order to analyze the accuracy of the model, a database integrated by 92 tests of exterior and interior beam-column joints is collected from the literature. Noting that the original model does not consider the effect of confinement product of adjacent elements to the connection, this effect is introduced through factors that reduce the values of the longitudinal and transverse strain used to calibrate the angle of the strut. In addition, the contribution of the transverse reinforcement in the capacity of the element is included. These modifications together with the influence of the boundary reinforcement, yields a good strength estimate for exterior and interior joints that fail in shear. When comparing with other models from the literature, it is observed that the proposed model provides one of the best correlations. [ABSTRACT FROM AUTHOR]

RC structural slender walls under large seismic excitation are expected to reach base moment capacity mainly affected by the first vibration mode. However, the base shear could be affected by higher modes once yielding in flexure has occurred, which might result in base shear underestimation in linear design. In this work, an experimental program is carried out on five RC rectangular walls 1:10 scaled. All five specimens considered irregularities at base, common in construction and one specimen did not consider shear reinforcement or boundary detailing. Tests are carried on a unidirectional shaking table and excitation is based on two Chile earthquake records with different intensities. Damage is concentrated at the wall base for all specimens; primary due to flexure with some participation of shear. For one of the records an average amplification of 1.3 is obtained, and a decrease in height of the resultant equivalent lateral force closes to 0.4 hw. By increasing the intensity of the input record, amplification grows to an average of 1.7, while it decreases drastically when subjected to input records with low frequency content. No significant difference is observed in shear amplification in specimens with a base central opening, nor with setback, even though the cracking and failure mode was different for such specimens. Ductility demand shows no correlation when two different earthquakes are considered, whereas the frequency content and Arias intensity (Ia) of the input record directly affected the shear amplification. [ABSTRACT FROM AUTHOR]

The capacity of structural systems subjected to shear loads commonly distinguished by discontinuities such as point loads or supports, or abrupt changes of cross section, where complex fields of stresses and strains are generated, is vital information for design. Four structural systems that present stress concentration due to applied shear loads are commonly short walls, deep beams, corbels and beam-column joints. In the present work a model is developed to predict the shear capacity of these elements based on a panel model that considers average strain and stresses in a reinforced concrete orthotropic material, which covers the section of the structural element subjected to stress concentration. In addition, the panel element complies with the longitudinal equilibrium, by equalizing the applied axial load with the internal stresses of the structural element, requiring constitutive material laws for both concrete and steel reinforcement. The original model that has shown good shear strength prediction requires solving the non-linear equation of vertical equilibrium. Thus, this work eliminates the need to solve the iterative problem for the capacity estimation of four possible limit states (failure of concrete in tension and compression, and yielding of longitudinal web and boundary reinforcement). For that, an expression is calibrated for the strain of the model with respect to relevant parameters, for each limit state, that allow the generation of a non-iterative model. The model results in an average predicted capacity over experimental capacity ratio, V model / V test , of 1.0 and a COV of 0.25, with similar performance for all four structural systems. When comparing these results with the general model that requires an iterative method, a similar performance is observed, with an average strength ratio and COV of 0.98 and 0.23, respectively. Likewise, in comparison with the ACI 318, the latter shows worse predictions (on average 24% lower) and with greater scatter (on average 28% higher). The expression in AASHTO code presents better correlation than ACI with predictions closer the proposed model. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is an element with a high influence in seedling growth in the nursery. Nevertheless, absolute levels of nutrient concentration are irrelevant if the relationship among the major elements is not examined. In this work we studied the incidence of several N concentrations in two proportional relationships with potassium (K), keeping the relationship with phosphate (P) constant (i.e. 3:2:1 and 3:2:3 for N:P:K), during the rapid growing phase in the fertigation production of Austrocedrus chilensis seedlings. Seedling height, stem diameter at the collar level, total biomass, aboveground/underground biomass ratio (PSA/PSR), nutritional status and root growth potential (RGP) were measured at the end of the growing season. The two treatments combining lower concentration of N with a relationship 3:2:3 produced the highest effect on all morphological parameters assessed. The PSA/PSR was more equilibrated in the treatments with the relationship 3:2:3. The N concentration in the leaves was proportional to its concentration in the nutrient solution. The P content did not show differences among treatments, whereas the K level was higher for the treatment of lower N concentration with relationship 3:2:1. The RGP was low in all treatments. Our observations showed that the 3:2:3 relationship produced larger seedlings with a better balance of biomass partition, evidencing that the management of K in the nutrient solution has higher influence in the seedlings growth of Austrocedrus chilensis. [ABSTRACT FROM AUTHOR]

This work evaluates experimentally the use of steel or polypropylene fibers in shotcrete as a partial replacement for the traditional reinforcement of electrowelded mesh used at the tunnel support for the subway in Santiago (Chile). For the experimental part, 8 tests were performed on section-scaled (1:2) slender (half-span to depth ratio a/d ∼ 5) specimens under transversal (flexure and shear) and axial loads (0.02f′ c A g and 0.07f′ c A g ) and with different reinforcements layout; and another 4 tests of similar specimens, but with low half-span to depth ratio (a/d ∼ 1.5). The section includes welded mesh (one face), a central reticulated frame and a plane shotcrete with a welded mesh (opposite face) or reinforced shotcrete (steel or polypropylene). The results showed a very important contribution of the reticulated frame in flexion (main internal reinforcement) and a modest contribution of the welded mesh and fibers. A two-dimensional finite element modeling of the tunnel-ground system using OpenSees is also performed using calibrated models for the tunnel section based on the experimental part. The soil is modeled with 9-node quadrilateral elements, the lining is modeled with beam-column elements with fiber sections, and the interaction between the lining and the soil is modeled by the Winkler approach without tension in the direction normal to the contact surface and with perfect adherence in the tangential direction. The model is subjected to the static loads from the excavation, modeled considering the constructive sequence of the tunnel using the α method, and then to a seismic analysis by means of the shear wave method (distortion). The results show that the safety factors implicit in the traditional design are high, implying that the structure remains elastic. [ABSTRACT FROM AUTHOR]

Slender walls with discontinuities at their bases, such as flag walls or walls with door openings or access, are common in Chilean practice because of the architectural requirements at facades, first floors, and underground levels. However, there is limited information about the behavior of such elements, and no designs or guidelines in the current codes consider the effects of discontinuities at the base. In this work, two analytical models are presented that estimate the yield displacement, yield curvature, and ultimate curvature of walls with openings, such as flag walls (setback), based on the dimensions of the opening and the longitudinal boundary steel ratio calibrated from a parametric analysis of a nonlinear finite element model. The results indicate that these discontinuities can have a major impact on the elastic displacement, reducing it because of the presence of a more rigid section above the opening, and also on the inelastic component, by increasing the curvature (and the strain) at the wall base because the opening tends to confine the plastic hinge within that area. [ABSTRACT FROM AUTHOR]

Health education is fundamental in the management of RA patients. This study explored patient needs for educational material appropriate for RA patients in our region through a website. This study includes seven focus groups and semi-structured interviews across 4 countries (Argentina, Chile, Colombia, and Mexico) with 71 RA patients. Transcripts were analyzed by anthropologists using qualitative analysis (QA), resulting in themes and subthemes to be developed. Five themes and over 50 subthemes of interest were identified by patients. Grouped into categories as follows: (1) knowing the disease, (2) living with arthritis, (3) treatment and therapies for RA, (4) psychosocial support, and (5) information for families. A response was written by the team in plain Spanish on patient subthemes of interest including additional areas that the team considered relevant. Three videos for YouTube were produced: on patient-doctor relationships, patients at work, and home and at the clinic. Illustrations in a comic book format on RA diagnosis were created. The educational site on RA of PANLAR can be found at htpp://artritisreumatoide.cl. This project accomplished a comprehensive list of RA patient interests, revealing the complex relationship between the information on the disease, the experience of a chronic disease, and the way in which patients approach, conceive, and manage their disease. We expect to gather information on how the website will be used in the future for patients and their families and maintain and improve the website as well as adapt its content to different socioeconomic realities. [ABSTRACT FROM AUTHOR]

This work deals with the piston failures found in diesel engines functioning in light trucks. The failure was a hole inside the bowl located at the top of the piston, which is the combustion chamber of the engine. This hole progressed and finds its way out between the second and third rings. The operational characteristics of the engine were analyzed in order to elucidate the probable acting failure mechanisms. For the evaluation, obviously were assessed the damaged pistons but also pistons of the same engine without the mentioned failure and a new piston. Different studies and measurements were carried out such as microstructural morphologies and transformations, hardness, fracture surface analysis and chemical composition. The piston design, the material used and the operational conditions (thermal and mechanical) were studied with the purpose of determining the failure origin. It was concluded that thermomechanical fatigue along with some degree of degradation suffered by the material is responsible of the reported failure. [ABSTRACT FROM AUTHOR]

The generation of multigroup neutron cross-section libraries is a key issue of the multigroup transport calculations in reactor physics. The correct choice of the boundaries of the energy groups, in particular, is decisive for obtaining reliable results. Knowledge of the reactor physics, general and specific of the studied reactor, along with long and refined analyses are required for finding out a reasonable energy structure, which is specific for the considered reactor and might be unsuitable for other systems. The genetic algorithm presented in this work aims to choose the most appropriate energy structure for the considered system to collapse a fine multigroup library into a few-groups one, usable for transient transport calculations. The user is free to choose the number of energy groups of the final library, which is in direct relation with the precision required and the time available for the simulation. The methodology is coupled with SIMMER-III code and applied to 3 reactor systems: ESNII+ ASTRID, ESFR and MSFR. The results show that the algorithm can find representative energy structures, providing accurate results on the multiplication factor. The results of each test are analyzed, showing how different compositions, geometries and neutron spectra guide the algorithm choices, so demonstrating the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Reinforced concrete structural walls are commonly used to provide lateral strength and stiffness to resist lateral loads from wind or earthquake. Slender walls usually require large amounts of longitudinal reinforcement at wall boundaries to satisfy code lateral strength requirements; therefore, use of structural steel reinforced concrete (SRC) walls, where the boundary longitudinal reinforcement is replaced by a structural steel section, is a potentially attractive alternative. This study presents results of an experimental program involving tests under combined gravity and lateral loading for three, heavily instrumented, moderate-scale SRC slender walls. Primary test variables included varying the size of the embedded structural steel section and the quantity of transverse reinforcement provided at the wall boundaries. Although slip of the structural steel was observed for all specimens, test results reveal good behavior up to and beyond 2% lateral drift, even for a specimen with only modest confinement at the wall boundaries. [ABSTRACT FROM AUTHOR]

Observations following recent earthquakes, and from structural testing, indicate numerous brittle compression failures in reinforced concrete seismic-resisting walls. This is unexpected, as most seismic-resisting walls are designed to be tension-controlled. The problematic compressive response led to two independent studies, each individually aimed at identifying design and loading parameters that affect the seismic deformability of the compression regions (or boundary elements) of seismic-resisting walls. These experimental studies are combined here for a more complete understanding. Both studies used axially loaded, rectangular reinforced concrete specimens that simulate seismic-resisting wall boundary elements. The rectangular prisms were tested under cyclic axial loading or monotonic compression, with a focus on the following parameters: boundary element detailing classification, detailing of transverse reinforcement, maximum tensile strain preceding compressive demand, and cross-sectional aspect ratio. Test results indicate that expected strength and deformation capacity can be overestimated unless a rectangular hoop restrains every longitudinal reinforcing bar; use of crossties does not guarantee stability of the longitudinal reinforcement. Tensile strains of 2 and 5%, imposed prior to reaching the compressive capacity, resulted in compression strength reductions of 20 and 50%, respectively, indicating that load-history can also be important. [ABSTRACT FROM AUTHOR]

This work studies the rolling contact fatigue (RCF) behavior of austempered ductile iron samples coated with Ti/TiN by cathodic arc deposition. The influence of the TiN layer thickness on the characteristics and RCF life of the coated samples is analyzed. RCF tests were performed in a flat washer type testing rig, using a thrust ball bearing as a counterpart. The maximum contact pressure was 1400 MPa. RCF tests results were analyzed using the two-parameter Weibull distribution. The rolling track of the tested samples was examined by using SEM and EDS. The results show that the surface hardness, residual stresses and coating adhesion strength of the samples increase as TiN layer thickness increases while surface roughness, coating hardness and elastic modulus do not vary significantly with the TiN layer thickness. Regarding the RCF tests, two failure mechanisms were observed in the coated samples, coating delamination and substrate spalling. Coating delamination turned out to be the most predominant mechanism and occurred at fewer loading cycles than substrate spalling. The EDS analysis revealed that inside the delaminated areas the Ti interlayer remained adhered to the substrates in all the cases. Extended tests on delaminated samples show growing delamination until final failure by substrate spalling occurred. The Weibull analysis indicates that the RCF life of the coated samples seems to have a tendency to increase with the TiN layer thickness and, in the case of the thicker TiN layer, to exceed the life of uncoated ADI after the extended tests. However, due to the number of samples employed, the statistic analysis does not show significant differences in the RCF behavior of the uncoated and coated samples. [ABSTRACT FROM AUTHOR]

This article will seek to reflect on a series of experiences with elementary school teachers from the city of Buenos Aires concerning ideas on slavery and Afro-descendants in the colonial period and during the wars for independence. It is an account of representations that have circulated on these topics in school events, textbooks and instructional materials. Next, the paper focuses on an educational experience aimed at the questioning of those traditions from the production of didactic sequences that considered a multisensory teaching. Thus, teachers appropriated the new knowledge and were protagonists of the curriculum development. [ABSTRACT FROM AUTHOR]

This paper presents a neutronic benchmark between the FRENETIC and the SIMMER codes, performed considering the core of the ALFRED lead-cooled fast reactor. FRENETIC includes a nodal diffusion module developed for fast full-core analyses of safety-relevant transients in liquid-metal fast reactors, while SIMMER is a reference tool for qualifying such kind of systems in accidental conditions. In order to highlight the influence of the different numerical methods available in the two codes on the output responses, macroscopic parameters like the effective multiplication factor and the linear power are compared in an increasingly detailed simulation framework. The 3D full-core FRENETIC results are compared at first to a cylindrical 2D SIMMER core model, to highlight the impact of the absorber rings location. Then, a 3D full-core model is also employed in SIMMER to assess the differences, with respect to FRENETIC, induced by the adoption of a Cartesian mesh and of the discrete ordinates method. The full input data consistency is ensured providing the same set of few-group material constants, generated with the Monte Carlo code Serpent 2. Finally, the W- ε scheme is applied to accelerate the angular and spatial convergence of the k eff sequences computed by SIMMER in order to estimate the asymptotic errors with respect to the reference Serpent calculation. [ABSTRACT FROM AUTHOR]

The histopathology of lepromatous skin varies according to the cell-mediated immunity of the host against Mycobacterium leprae . In tuberculoid and borderline tuberculoid leprosy, epithelioid noncaseating granulomas predominate, and acid-fast bacilli (AFB) are absent or only rarely present. In borderline lepromatous and lepromatous leprosy, the infiltrate is composed of macrophages with a vacuolar cytoplasm, lymphocytes, and plasma cells. AFB are numerous. Edema inside and outside the epithelioid granulomas, together with the appearance of large giant cells, are the main features of type 1 reactions. A conspicuous neutrophilic infiltrate in the subcutis with or without vasculitis is found in erythema nodosum leprosum. The main histopathologic features of leprosy and its particular forms are discussed in this review. [ABSTRACT FROM AUTHOR]

Squat reinforced concrete walls require enough shear strength in order to promote flexural yielding, which creates the need for designers of an accurate method for strength prediction. In many cases, especially for existing buildings, strength estimates might be insufficient when more accurate analyses are needed, such as pushover analysis. In this case, estimates of load versus displacement are required for building modeling. A model is developed that predicts the shear load versus shear deformation of squat reinforced concrete walls by means of a panel formulation. In order to provide a simple, design-oriented tool, the formulation considers the wall as a single element, which presents an average strain and stress field for the entire wall. Simple material constitutive laws for concrete and steel are used. The developed models can be divided into two categories: (i) rotating-angle and (ii) fixed-angle models. In the first case, the principal stress/strain direction rotates for each drift increment. This situation is addressed by prescribing the average normal strain of the panel. The formation of a crack, which can be interpreted as a fixed principal strain direction is imposed on the second formulation via calibration of the principal stress/strain direction obtained from the rotating-angle model at a cracking stage. Two alternatives are selected for the cracking point: fcr and 0.5fcr (post-peak). In terms of shear capacity, the model results are compared with an experimental database indicating that the fixed-angle models yield good results. The overall response (load-displacement) is also reasonable well predicted for specimens with diagonal compression failure. [ABSTRACT FROM AUTHOR]

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most prevalent non-Hodgkin lymphomas that comprise cutaneous T-cell lymphomas (CTCL), accounting for more than 70% of cases. Following the Tumor Lymph nodes Metastasis Blood system, disease staging is carried out, and within ten years, about thirty percent of patients in the early stages will have advanced disease. Plaques, folliculotropism, and age over 60 are risk factors for progression. A 5-year survival rate of less than 20% is associated with LCT in MF. Treatment requires an interdisciplinary approach; skindirected therapies are available for early stages of the disease, but there are no curative options for advanced stages of the disease other than allogeneic stem cell transplantation. Because of their severe symptoms and poor treatment efficacy, patients in advanced stages have a lower quality of life and a lower chance of survival. In patients with CD30-expressing CTCL, Brentuximab Vedotin has demonstrated better response rates and progression-free survival (PFS); in advanced SS, mogamulizumab has significantly increased PFS. These findings emphasize the need to standardize prognostic factors and improve CTCL treatment. [ABSTRACT FROM AUTHOR]