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Wear on the surface of the femoral head increases the risk of hip and femur fractures. Biomechanical experiments conducted on the femur are based on its bending and torsional rigidities. Studies regarding the deflection of the femur bone when the femoral head is coated with microfilms composed of durable and compatible biomaterials are poor. This study aimed to investigate the effects of different biomaterial microfilm coatings over the femoral head on the deflection of the human femur. We utilized 2023 R1 finite element analysis (FEA) software to model the directional deformation on the femoral head and examine the femur's deflection with varying microfilm thicknesses. The deflection of the femur bone was reported when the femoral head was uncoated and coated with titanium, stainless steel, and pure gold microfilms of different thicknesses (namely, 50, 75, and 100 μm). Our results show that the femur's minimum and maximum deflection occurred for stainless steel and gold, respectively. The deformation of the femur was lower when the femoral head was coated with a 50-micrometer microfilm of stainless steel, compared to the deformation obtained with gold and titanium. When the thickness of the microfilm for each of the materials was increased, the deformation continued to decrease. The minimum deformation of the femur occurred for a thickness of 100 μm with stainless steel, followed by titanium and gold. The difference in the directional deformation of the femur between the materials was more significant when the coating was 100 μm, compared to the thicknesses of 50 and 75 μm. The findings of this study are expected to significantly contribute to the development of advanced medical techniques to enhance the quality of life for patients with femur bone-related issues. This information can be used to develop more resilient coatings that can withstand wear and tear. [ABSTRACT FROM AUTHOR]

Lymphoid interstitial pneumonia (LIP) is a rare form of interstitial pulmonary disease, which has been described in association with a wide range of autoimmune disorders. Although the association of this entity with Sjogren's syndrome is well known, only a few cases are reported in relation to systemic lupus erythematosus (SLE). The aim of this paper is to review the cases reported in literature to date, as well as to describe the characteristics of these patients including the new case presented herein. We will be focusing on the case of a 36-year-old female patient diagnosed with SLE on hydroxychloroquine treatment who develops pleuritic chest pain and progressive dyspnea after 3 years of follow-up. The chest CT scan showed pleural thickening and both multiple and bilateral micronodules. A lung biopsy was also performed, revealing an infiltration of lymphocytes, plasma cells, and histiocytes in the alveolar septa suggestive of LIP. After conducting a review of the literature, we identified seven other cases describing SLE in association with LIP. The majority of them were young women, and LIP tends to appear early in the course of the disease, even as a form of initial presentation in some cases. Symptoms included cough, dyspnea, and pleuritic pain, with the exception of one case which was asymptomatic. It is noteworthy that half of the patients were positive for anti-SSA/anti-SSB autoantibodies, and some of them also met criteria for Sjogren's syndrome. Treatment with steroids and other immunosuppressive agents improved symptoms in all of them. [ABSTRACT FROM AUTHOR]

This work aims to contribute to studies on the geometric optimization of thermoelectric generators (T E G s) through a combination of the reduced variables technique and supervised machine learning. The architecture of the thermoelectric generators studied, one conventional and the other segmented, was determined by calculating the cross-sectional area and length of the legs, and applying reduced variables approximation. With the help of a supervised machine learning algorithm, the values of the thermoelectric properties were predicted, as were those of the maximum electrical power for the other temperature values. This characteristic was an advantage that allowed us to obtain approximate results for the electrical power, adjusting the design of the T E G s when experimental values were not known. The proposed method also made it possible to determine the optimal values of various parameters of the legs, which were the ratio of the cross-sectional areas (A p / A n) , the length of the legs (l) , and the space between the legs (H) . Aspects such as temperature-dependent thermoelectric properties (Seebeck coefficient, electrical resistivity, and thermal conductivity) and the metallic bridge that connects the legs were considered in the calculations for the design of the T E G s , obtaining more realistic models. In the training phase, the algorithm received the parameter (H) and an operating temperature value as input data, to predict the corresponding value of the maximum power produced. This calculation was performed for conventional and segmented systems. Recent advances have opened up the possibility of applying an algorithm for designing conventional and segmented thermocouples based on the reduced variables approach and incorporating a supervised machine learning computational technique. [ABSTRACT FROM AUTHOR]

The objective of this study is to use DNA barcoding to link cystacanths and adults belonging to the acanthocephalans Corynosoma australe found in the Southeastern Pacific Ocean off the coast central from Peru. We sampled three species of commercial fish (Paralichthys adspersus (Steindachner), Paralabrax humeralis (Valenciennes), and Cheilodactylus variegatus (Valenciennes)) and two South American sea lions, Otaria byronia, stranded on the beaches of the city of Huacho and Barranca, Lima province. A total of 509 acanthocephalan larvae were found in the body cavity of 95 fish (prevalence 54.28%, total mean intensity 8.64). A total of 127 adult worms were found in the large intestine from two South American sea lions (P= 100%, MI= 63.5). A total of 203 larvae from P. humeralis were isolates (P=65.71%; MI= 8.83; MA=5.8), 235 (P=54.29%; MI= 12.37; MA= 6.71) from C. variegatus, and 71 (P=42.86%; MI= 4.73; MA= 2.03) from P. adspersus. All adult and larval specimens were morphologically identified as C. australe. They were generated cytochrome c oxidase subunit 1 (cox1) gene sequences of specimens and were compared with available data from GenBank. Molecular phylogenetic analysis supported our morphological identification, where the Peruvian isolates formed a clade with other isolates of C. australe from other countries of the American continent. Of the sequences obtained, two haplotypes were detected and were not identical with previous reports. Based on both DNA barcoding and morphological analyses, our finding represents the first molecular data of C. australe from Peru and the report of Cheilodactylus variegatus as a new paratenic host on the central coast, extending the knowledge and distribution range of this acanthocephalan in Southeastern Pacific Ocean. [ABSTRACT FROM AUTHOR]

Background: Spasticity is a frequent symptom of multiple sclerosis (MS), which may negatively influence daily living activities (ADL). Objectives: To (1) explore the feasibility to conduct a structured interview by specialist nurses about limitations in ADL; (2) determine the percentage of people with MS (PwMS) with limitations in ADL related to spasticity; (3) to assess the knowledge about spasticity and describe its clinical features. Design: Observational, cross‐sectional, multicentre study in 16 MS units of Catalonia (Spain). Participants were recruited from the outpatient facility and day‐care hospital between July 2018 and June 2019 and met the following criteria: (1) age 18 or older, (2) diagnosis of MS according to McDonald criteria 2010 and (3) no clinical relapse in previous 30 days. Methods: Specialist nurses conducted a structured interview divided in two parts: the assessment of (1) limitations in the ADL and (2) the presence of spasticity and associated symptoms. The usefulness of this intervention was requested. This study met the STROBE reporting guidelines checklist for observational studies. Results: Three hundred sixty eight pwMS (244 women) with a mean age of 46 years and a median Expanded Disability Status Scale score of 2.5 (range, 0–8.5) were included. 262 (71%) pwMS had limitations in the ADL, and spasticity was reported as the most limiting symptom in 59 (23%). As a result of the interview, spasticity was observed in 199 (76%) participants; 47 (24%) of them were unaware that they had spasticity and 102 (51%) would not have reported it spontaneously. The level of the interview satisfaction was high (90%). Conclusions: Spasticity is a complex and limiting symptom in MS. The structured interview conducted by specialist nurses is feasible and has good acceptance. Patient contribution Specialist nurses can be proactive in MS clinical assessment, which may help to detect symptoms with negative impact on quality of life. [ABSTRACT FROM AUTHOR]

Copyright of Artnodes is the property of Universitat Oberta de Catalunya and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dynamis is the property of Dynamis - Facultad de Medicina de la Universidad de Granada and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A thermoelectric generator (TEG) is studied by considering different leg structures of hollow/filled legs, using new cooling nanofluids, and analyzing the segmentation effect. TEG performance is characterized by power output, conversion efficiency, and exergy efficiency. This study shows the impact of different cooling nanofluids (TiO2, graphene, and Al2O3) on the performance of the thermoelectric generator. Furthermore, in the comparative analysis of nanofluid cooling enhancement for TEG, different hollow/filled thermoelectric legs recently proposed in the literature are considered. Likewise, three segmentation types are used, 2n-2p, 1n-2p, and 2n-1p, thus will be compared with the results of the unsegmented legs. This study calculates the performance of thermoelectric leg structures through a validated numerical simulation on the ANSYS Workbench (modeling, design, and simulation). In addition, the optimal working conditions are evaluated. This study found that quenching of nanofluids can improve TEG performance by up to 17% compared to distilled water. However, the performance improvement of the TEG for each nanofluid is small between them. Furthermore, segmentation of n-type thermocouples improves efficiency and exergy, whereas segmentation of p-type thermocouples improves output power. The segmentation enhances performance by up to twice that of non-segmented leg structures; hollow structures are better performers. In the results, it is reported that the 2n-1p segmentation is the one with the best performance, reaching a maximum energy efficiency of 38%. The triangular leg structure improves performance by up to 75% compared to the rectangular and square leg structures. Likewise, using TiO2 is the best cooling option with nanofluids since it improves performance by 17% compared to distilled water. Furthermore, the results of cooling nanofluids for TEG performance are useful for the design of thermoelectric leg structures and stimulate further research. [ABSTRACT FROM AUTHOR]

Roof runoff is collected rainwater from a roof using a rainwater harvesting system (RWHS). The construction of an efficient RWHS requires a thorough analysis of the rainwater quality and the appropriate treatment process for its intended use. In line with this, a bibliometric and comprehensive review of studies related to roof rainwater harvesting was conducted. A corpus of 1123 articles was downloaded from the Scopus database and parsed through the CorText Manager to determine the relationships between keywords, journals, and topics related to rainwater harvesting. A comprehensive analysis was also conducted to determine the different designs of RWHS, the quality of harvested rainwater from roof catchments, the efficiency of the system for specific purposes, and its sustainability in terms of economic, environmental, and social aspects. Results show that the effectiveness of a RWHS heavily depends on its installation site, the physicochemical characteristics of the harvested rainwater, and the acceptability of the end users. An effective water treatment process is essential for achieving better water quality for harvested rainwater. Moreover, assessing the financial viability and return on investment of an RWHS is necessary. [ABSTRACT FROM AUTHOR]

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gaceta Médica de Caracas is the property of Academia Nacional de Medicina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

First flush is a phenomenon in stormwater runoff that has been considered a topic of great interest in the field of nonpoint source pollution. Despite several attempts to define the first flush quantitively, the specified characteristics of the phenomenon vary among sources. To address these uncertainties, a bibliometric and comprehensive review on published articles related to first flush was conducted. A corpus of 403 research articles was obtained from the Scopus database, which was then parsed using the CorText Manager for the bibliometric analysis. The study examined quantitative definitions of first flush from various sources; climate and topographic characteristics of monitoring and experimental sites where the studies on first flush were performed; the sample collection methods applied; the first flush values obtained on the studies and how it influenced the nonpoint source pollution in urban watersheds. A network map, two contingency matrices, and a Sankey diagram were created to visualize the relationship of significant keywords related to first flush, as well as their co-occurrences with journals, countries, and years. It was found that the strength of the first flush effect could vary depending on the geographical location of the site, climatic conditions, and the pollutants being analyzed. Therefore, initial rainfall monitoring, runoff sampling, and water quality testing were seen as critical steps in characterizing the first flush in urban catchments. Furthermore, the characterization of first flush was found to be significant to the selection of best management practices and design of low-impact development (LID) technologies for stormwater runoff management and nonpoint source pollution control. [ABSTRACT FROM AUTHOR]

We model the charge, spin, and heat currents in ferromagnetic metaljnormal metaljnormal metal trilayer structures in the two current model, taking into account bulk and interface thermoelectric properties as well as Joule heating. The results include the temperature distribution as well as resistance-current curves that reproduce the observed shifted parabolic characteristics. Thin tunneling barriers can enhance the apparent Peltier cooling. The model agrees with the experimental results for wide multilayer pillars, but the giant effects observed for diameters ≲100 nm are still under discussion. [ABSTRACT FROM AUTHOR]

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: In this work, a simulation model based on finite element analysis for a one‐dimensional p‐type segmented semiconductor element with different cross‐sectional areas is analyzed to predict transient thermal behavior for thermoelectric coolers (TECs). The proposed model considers all thermoelectric effects, including the Peltier effect, Thomson effect, Joule heating, and Fourier's heat conduction. The supercooling occurs when a pulse current higher than the steady‐state optimum current is applied to a TEC. Dynamic characteristics, such as minimum cold side temperature and holding time of transient state, which arise in transient supercooling are very important to be considered for the design and operation of TECs. In this study, we present a new approach of transient performance based on leg geometry shape, considering variable cross‐sectional areas, as well as individual element lengths of two different thermoelectric materials using a segmentation model proposed. A variety of model designs are analyzed, considering rectangular, trapezoidal, and inverse trapezoidal legs, where also optimum pulse current is found as a function of the element lengths. It is demonstrated that an improvement of 4.75% in the cooling is possible when using trapezoidal legs compared with conventional rectangular systems. Our presented model is mainly a new alternative in characterizing Peltier supercooling as a function of both pulse current ratio as well as the leg shape. [ABSTRACT FROM AUTHOR]

In this study, we report the novel energy behavior of high-performance nanostructured materials in a segmented thermoelectric micro-generator (TEG). Several physical elements of the materials must be considered to determine their behavior in the thermoelectric energy conversion: temperature dependence of material properties, geometric structure, segmentation, and the symmetry of each or both p-type and n-type nanostructure semiconductor thermoelements. Recently, many efforts have reported effects independent on the thermoelectric performance of semiconductor materials. In this work, exhaustive research on the performance of high-performance nanostructured materials in a segmented thermoelectric micro-generator (TEG) was carried out. Our results show the efficiency and output power of the TEG using the temperature-dependent model, i.e., a variable internal resistance for a load resistance of the system. Our approach allows us to analyze symmetrical and asymmetric geometries, showing maximum and minimum peaks values in the performance of the TEG for specific γ values. The performance of the TEG is improved by about 6 % and 7 % , for efficiency, and output power, respectively, considering a trapezoidal geometric shape in the 2p-3n segmented system, compared with the conventional rectangular shape. [ABSTRACT FROM AUTHOR]

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An observational and descriptive study including patients discharged for COVID-19 was carried out by the COVID-19 Working Group of the Hospital Clínico San Carlos (HCSC). We aimed to identify the main symptoms after 90 days of hospital discharged. A structured interview was conducted, through a "checklist" that included symptoms within the 90 days post-discharge. A total of 134 patients were enrolled. The most frequently referred symptoms were asthenia, dyspnea and weight loss. Anxiety was the most frequent psychological symptom found through the GAD-7 scale. [ABSTRACT FROM AUTHOR]

Organizational transformation is an interesting topic in theory and practice. Achieving organizational transformation is seen as a huge challenge for managers as there are many aspects that the organization needs to deal with. During the COVID-19 lockdown, organizations faced an urgent need to radically transform in order to survive. Moreover, the economic and social context of the Mexican economy makes it even more important to understand how organizations can radically transform as, in theory, such a context seems to be detrimental for organizational transformation. This study analyzed 21 organizations based in Mexico and pays special attention to 5 organizations that achieved radical organizational transformation. The main takeaway point from this study is that the five organizations that achieved radical transformation had at least four things in common. First, senior managers were strongly convinced that without radical transformation the firm would perish before the end of the year. Second, these five organizations quickly reshaped their management control systems. Third, the five organizations that achieved a radical change hired specialized consultants to achieve the transformation. Finally, these organizations also outsourced to external firms to complete processes where they themselves did not have any previous experience. This article contributes to a better understanding of organizational transformation. [ABSTRACT FROM AUTHOR]

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In organic agriculture, the resources available in the region are used sustainably in order to reduce production costs, especially those related to fertilization. The use of organic fertilizers is an alternative for achieving this purpose. The objective of the present work was to evaluate the effect of solarized bovine manure on the production and quality of tomato fruits. A randomized block design with six repetitions was used; the treatments were four doses of solarized manure (0, 40, 80, 120 t ha-1). There was no significant difference for the variables plant height, number of fruits and yield between the different doses of manure, however, with the application of 120 ton ha-1 the content of β-carotene and anthocyanins was increased by 60.14 and 64.17%, compared to the witness, respectively. Significant differences in soil pH and EC were recorded at the end of the crop cycle. The use of solarized manure is a sustainable option for the production of tomato in shade mesh, since similar results were obtained without the application of inorganic fertilization. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The question of whether the known virial coefficients are enough to determine the packing fraction η∞ at which the fluid equation of state of a hard-sphere fluid diverges is addressed. It is found that the information derived from the direct Padé approximants to the compressibility factor constructed with the virial coefficients is inconclusive. An alternative approach is proposed which makes use of the same virial coefficients and of the equation of state in a form where the packing fraction is explicitly given as a function of the pressure. The results of this approach both for hard-disk and hard-sphere fluids, which can straightforwardly accommodate higher virial coefficients when available, lends support to the conjecture that η∞ is equal to the maximum packing fraction corresponding to an ordered crystalline structure. [ABSTRACT FROM AUTHOR]

A recently derived method [R. D. Rohrmann and A. Santos, Phys. Rev. E 76, 051202 (2007)] to obtain the exact solution of the Percus–Yevick equation for a fluid of hard spheres in (odd) d dimensions is used to investigate the convergence properties of the resulting virial series. This is done both for the virial and compressibility routes, in which the virial coefficients Bj are expressed in terms of the solution of a set of (d-1)/2 coupled algebraic equations which become nonlinear for d≥5. Results have been derived up to d=13. A confirmation of the alternating character of the series for d≥5, due to the existence of a branch point on the negative real axis, is found and the radius of convergence is explicitly determined for each dimension. The resulting scaled density per dimension 2η1/d, where η is the packing fraction, is wholly consistent with the limiting value of 1 for d→∞. Finally, the values for Bj predicted by the virial and compressibility routes in the Percus–Yevick approximation are compared with the known exact values [N. Clisby and B. M. McCoy, J. Stat. Phys. 122, 15 (2006)]. [ABSTRACT FROM AUTHOR]

Following the work of Leutheusser [Physica A 127, 667 (1984)], the solution to the Percus-Yevick equation for a seven-dimensional hard-sphere fluid is explicitly found. This allows the derivation of the equation of state for the fluid taking both the virial and the compressibility routes. An analysis of the virial coefficients and the determination of the radius of convergence of the virial series are carried out. Molecular-dynamics simulations of the same system are also performed and a comparison between the simulation results for the compressibility factor and theoretical expressions for the same quantity is presented. [ABSTRACT FROM AUTHOR]