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Lowrider culture in Southern California and within Chicana/o social relations is a powerful example of minoritarian cultural production and an important yet undertheorized aesthetic, political, and gendered cultural object. Linking the lowrider enthusiast's body and this cultural object—their vehicle—as a continuous signifying spectrum of self-inscription reifıes an alternative understanding of lowrider identities. [ABSTRACT FROM AUTHOR]

The cost of electrical energy in an organic Rankine cycle (ORC), using high-temperature heat, is 0.5946 USD/kWh, with an efficiency of 40.80 % (2024), these parameters change significantly when using low temperature heat, up to 12.12 % efficiency and 0.95 USD/kWh of energy cost (2019). Exergy destruction defines the minimum area of the ORC evaporator and condenser and their total cost. The temperature of the working fluid at the evaporator outlet has a significant impact on the thermal efficiency of the system. Propane, butane and isobutane were used as working fluids to evaluate the exergy destruction in an ORC. In the analysis, the fluid temperature at the evaporator outlet is varied in a range of 80 to 120 °C. An exergo-economic evaluation was carried out for each of the working fluids. The fluid enters the turbine and undergoes an isentropic expansion of 6 bar to produce 3147.3 kW of power. For the three working fluids, the ORC evaporator presents the highest exergy destruction, followed by the condenser, the turbine and the pump. Propane exhibits the highest exergy destruction in the evaporator, 79 %. The ORC operated with butane presents the lowest exergy destruction in the evaporator among the fluids used (70 %), with an energy efficiency of 7.78. At a temperature of 110 °C, using butane as the working fluid, the smallest total area of the heat transfer equipment of 1,924 m2 and the lowest levelized cost of energy (LCOEel), 0.022 USD/kWh, were obtained. The exergo-economic evaluation allows determining the working fluid with the lowest exergy destruction, the lowest total area of the heat transfer equipment and the lowest energy cost. [ABSTRACT FROM AUTHOR]

In a coupled system heat pump-solar thermal energy, the heat pump represents 50 % of the total cost, while the compressor represents 92 % of the total heat pump cost. Refrigerant and mass flow rate directly determine the cost and the operation of the compressor. In this work, a thermo-economic study of a heat pump coupled to solar thermal energy was carried out to determine the minimum energy cost, depending on the mass flow, varying the degree of subcooling and guaranteeing for each flow rate and three selected refrigerants, the heat load and the target temperature required by an industrial process. The three selected refrigerants were: R600a (ODP=0, GWP=3), R245fa (ODP=0, GWP=1030) and R1234ze(Z) (ODP=0, GWP=1.4). A pulp bleaching process for paper production was used as a case study. The heat pump uses a network of low-temperature solar collectors as a heat source, it reaches a temperature of 70 and 80 °C and operates with an irradiance of 443 W/m2 . For each refrigerant, the minimum cost was calculated based on the degree of subcooling and the mass flow rate. Refrigerant R1234ze(Z) produces the lowest levelized cost (LCOEt) of 0.06058 $/kWh with a mass flow rate of 1.33 kg/s, a subcooling degree of 9 °C and a coefficient of performance (COP) of 3.19. The highest COP was 4.01 for the same refrigerant with a subcooling degree of 30 °C. By varying the mass flow rate of the refrigerant R1234ze(Z), the total cost of the heat pump can be reduced by up to 7 % and using other refrigerants by up to 26 % (R600a). Determination of the lowest total cost of the heat pump by varying the mass flow of the refrigerant allows reducing the energy cost by up to 19 %, making competitive the use of heat pumps feed with solar thermal energy for heat production. [ABSTRACT FROM AUTHOR]

Variability of the solar resource represents a challenge in the solar dehydration of fruits. To control the kinetics of solar dehydration, the behavior of the variables with the greatest impact on fruit dehydration is characterized: ambient temperature, relative humidity, wind speed and irradiance. 876,000 data of these four environmental variables were obtained from a meteorological station located in the city of Guanajuato (Mexico). The data correspond to the dehydration period of 8:00 to 18:00 h during the year 2023. Classified into quartiles and represented in Box-Whiskers diagrams, the data was analyzed in their distribution and symmetry. Experimental tests were carried out for apple dehydration during the four seasons of the year 2023, considering the shrinkage of the fruit (radius and thickness). The impact of environmental variables on the drying kinetics was determined. The shortest drying times of up to 5 h (April), were obtained even when the highest levels of wind speed were recorded (6.65 m/s). Ambient temperature and relative humidity significantly impact drying kinetics, increasing drying times by up to 40 %. This analysis allows standardizing the dehydration process in an indirect solar dehydrator even under variable punctual, monthly and seasonal environmental conditions. [ABSTRACT FROM AUTHOR]

The efficiency of an organic Rankine cycle (ORC) using low-temperature solar thermal energy, is 11 %, which increases the volume of the storage system and the solar thermal installation area that supplies the heat load to the ORC. Through a thermodynamic study of a coupled system heat pump-solar thermal installation using the R123 refrigerant, the efficiency of the ORC was increased significantly, and the installation area of the collector network and the volume of the storage system were reduced. Two case studies were evaluated: case 1, a sugar mill, and case 2, a fruit and vegetable cold room. Refrigerant R123 was selected with ODP = 0.02 and GWP = 77. The coupled system heat pump - solar thermal installation was designed to supply the power required by the process. The area of the solar thermal installation was reduced by 81 % compared to the area used to produce the same power in Case Study 1. The efficiency of the ORC increased from 11 to 14.5 % in both case studies. With the increase in efficiency and reduction in the installation area, the impact on the Earth is minimized, and greenhouse gas emissions are eliminated. [ABSTRACT FROM AUTHOR]

One‐dimensional zinc oxide nanomaterials (1DZnO) have emerged as promising, cost‐effective nanoplatforms with adjustable properties suitable for electrochemical and optical biosensing applications. In this work, modifications in the inherent photoluminescent response of 1DZnO are harnessed to develop a novel immunosensor tailored for detecting enteropathogenic Escherichia coli. This nanobiosensor demonstrates a modulation in photoluminescence signal, effectively responsive to analyte concentrations ranging from 1 × 102 to 1 × 108 CFU mL−1, with direct visualization of targeted bacterial cells over 1DZnO structures through scanning electron microscopy. The conceptualization of this nanobiosensor is focused on a real‐time contact strategy that can significantly reduce processing and response times for pathogen detection, prospected for emergency scenarios. With this aim, the detection process unfolds in real time, with a mere 5–10 s interaction time, corroborated by the standard polymerase chain reaction approach. This synergistic validation underscores the reliability and precision of the developed biosensor. Notably, the utility of 1DZnO nanoplatforms extends beyond the realm of enteropathogenic E. coli, as the biosensing performance exhibited here holds promise for analogous applications involving other medically pertinent pathogens. This study paves the way for the broader implementation of 1DZnO‐based biosensors in medical diagnostics, offering rapid, sensitive, and real‐time detection capabilities. [ABSTRACT FROM AUTHOR]

Background: Sports supplements (SSs) are widely used among team sport athletes; however, evidence supporting the use of SSs among football referees at the elite level is scarce. The aim of the present study was to analyze the consumption of SSs among referees with respect to their level of competition and referee type (main referees (MRs) vs. assistant referees (ARs)). Methods: A total of 106 football referees participated in this study, with 46.2% from the First Spanish Division and 53.8% from the Second Spanish Division, representing 84.13% of the total number of referees. Each participant completed a validated questionnaire about SS consumption, with the SSs classified according to the Australian Institute of Sport (AIS) ABCD system: Group A has strong evidence for enhancing athlete health and performance, Group B shows potential benefits but needs more evidence, Group C has inconclusive evidence against use, and Group D includes prohibited substances. Results: A total of 84.0% of the MRs and ARs reported the consumption of at least one SS. Differences were found only in the consumption of medical supplements between division (p = 0.016) and type of referee (p = 0.041), though no significant differences were found among the remaining AIS SS categories (p > 0.05). Sport performance (49.6%), Internet (41.0%), and dietitian–nutritionists (31.7%) were the primary reason for SS consumption, purchase location, and source of information, respectively. The most frequently consumed SS were whey protein (45.3%), followed by creatine (33.0%), sport bars and sports drinks (28.3%), and caffeine (19.8%). Conclusions: MRs and ARs reported a high prevalence of dietary supplement (SS) consumption, with significant differences between division and referee type observed only in medical supplement consumption. [ABSTRACT FROM AUTHOR]

Military organizations have adapted to the logic and dynamics of social media to transmit their institutional narratives. Instagram is the most popular social network, but one of the most understudied in relation to the Armed Forces. This research note presents a comparative study of the content of the official accounts of the Spanish, French, the United States, Israeli, and Australian armies throughout 2021 (n = 1,922). The specific objectives are to describe and analyze the hashtags, the accounts mentioned, and the main topics of the post. Results show that armies can convey multiple messages in a single post, and reveal that armies make similar use of Instagram, notwithstanding the various differences between Israel and the other armies due to organizational and contextual elements. [ABSTRACT FROM AUTHOR]

Objective: To introduce MexOMICS, a Mexican Consortium focused on establishing electronic databases to collect, cross-reference, and share healthrelated and omics data on the Mexican population. Methods: Since 2019, the MexOMICS Consortium has established three electronic-based registries: the Mexican Twin Registry (TwinsMX), Mexican Lupus Registry (LupusRGMX), and the Mexican Parkinson's Research Network (MEX-PD), designed and implemented using the Research Electronic Data Capture web-based application. Participants were enrolled through voluntary participation and on-site engagement with medical specialists. We also acquired DNA samples and Magnetic Resonance Imaging scans in subsets of participants. Results: The registries have successfully enrolled a large number of participants from a variety of regions within Mexico: TwinsMX (n = 2,915), LupusRGMX (n = 1,761) and MEX-PD (n = 750). In addition to sociodemographic, psychosocial, and clinical data, MexOMICS has collected DNA samples to study the genetic biomarkers across the three registries. Cognitive function has been assessed with the Montreal Cognitive Assessment in a subset of 376 MEX-PD participants. Furthermore, a subset of 267 twins have participated in cognitive evaluations with the Creyos platform and in MRI sessions acquiring structural, functional, and spectroscopy brain imaging; comparable evaluations are planned for LupusRGMX and MEX-PD. Conclusions: The MexOMICS registries offer a valuable repository of information concerning the potential interplay of genetic and environmental factors in health conditions among the Mexican population. [ABSTRACT FROM AUTHOR]

The population living in cities around the world will increase in the next decades. Conventional military forces will deploy more in constrained areas where their high-tech capabilities are not an advantage. This research provides an analytical framework for understanding the main challenges of urban warfare for conventional forces. The analysis identifies the military organizational dimension, dual-use technologies as game changers, and the role of civilian population in urban environments as key factors. The conclusions provide some policy recommendations concerning training and communication strategies. The prospects of urban warfare will be defined by a combination of cognitive and kinetic actions. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) or 3D printing of metals is gaining popularity due to its flexibility when fabricating parts with highly complex designs, as well as when simplifying manufacturing steps and optimizing process times. In this investigation, 17-4 PH stainless steel was additively manufactured using Laser Powder Bed Fusion (L-PBF), followed by functionalization through a DUPLEX treatment. This treatment involved a plasma-assisted nitriding process, followed by the deposition of an arc-PVD c-Al0.7Cr0.3N hard coating. The microstructural modifications resulting from plasma nitriding (such as the formation of Fe2,3N and Fe4N and the αN or expanded martensite phases) and the surface improvements with the c-Al0.7Cr0.3N coating on the 3D-printed 17-4 PH steel are evaluated in comparison to conventionally manufactured 17-4 PH steel. These microstructural characteristics are correlated with the mechanical response of the treated surfaces. As a result of the plasma nitriding process, the hardness of the 3D-printed 17-4 PH SS increased by approximately 260%. The wear, measured through dynamic and static scratch testing, was reduced by approximately 31%. This improvement was attributed to the modification of adhesive failure mechanisms, leading to a reduction in wear volume, improved coating adhesion, and enhanced scratch resistance. [ABSTRACT FROM AUTHOR]

"Theatre of the Sphere: The Vibrant Being" by Luis Valdez is a highly anticipated addition to the field of Latinx theater. It serves as both a history book and an acting manual, offering insights into Valdez's innovations as a playwright and theatrical innovator. The book explores the principles underlying Valdez's methodology, which is influenced by Mayan and Mexica Indigenous cultures. While the book has some limitations, it provides valuable resources for those interested in Chicano theater and offers a new approach to actor training that embraces Indigenous mythologies. [Extracted from the article]

The design of a solar thermal installation is based on the lowest irradiance levels that occur during winter. However, there are consecutive days with irradiance levels well below those used for the design, which are called in this work "critical irradiance levels". To solve this challenge, a statistical analysis is carried out to find a representative percentile of 22 years of consecutive days with "critical irradiance levels". A case study of a cotton-dyeing industrial process requires 18.5 m3 of hot water and operates for 2.75 h at temperatures between 40 and 90 °C. Environmental variables for 22 years were analyzed and validated to design a solar thermal installation (solar collector network and storage system) and a coupled heat pump. The fifth percentile, with three consecutive days and low irradiance levels, was the most repetitive. For this case, a storage system of 46.5 m3 guaranteed heat load at target temperature. The simple payback was 14.1 years, and the energy cost was 0.094 USD/kWh, which was competitive against the energy cost from using fossil fuels, 0.064 USD/kWh. The design based on critical environmental conditions guarantees a continuous supply of energy to the industrial process and defines the minimum availability of solar energy to supply a process. [ABSTRACT FROM AUTHOR]

Nowadays, considerable attention is paid to agile methods as a means to improve management of software development processes. The widespread use of such methods in professional contexts has encouraged their integration into software engineering training and undergraduate courses. Although several research efforts have focused on teaching Scrum through simulating a software development project, they covered only the learning of programming practices within a Scrum team. Furthermore, few studies tackle nontechnical skills other than the development practices themselves. The work presented here introduces an original Scrum-based training model enhanced with agile coaching to maximize student performance. This was validated by a case study on a capstone project in a Scrum course. This paper summarizes the positive results of introducing agile coaching, which resulted in approximately 22% more coverage of software engineering practices. In addition, a survey data showed that, compared to students who did not receive coaching, coached students gained valuable insight into the internalization of Scrum, problem solving, and guidance by means of checkpoint meetings.

The application of coatings with essential oils for food preservation is an alternative way to keep minimally processed apple slices fresh, nutritious, safe, sensory palatable, and accessible for consumers. In the present study, the effect of three bioactive coatings on quality variables of minimally processed Golden Delicious apple slices for 25-days at 4 °C was evaluated. The coatings were CT1-chitosan-based, CT2-guar gum-based, and CT3-composite guar gum-starch-based; all three coatings contained cinnamon essential oil and were compared with UCT0-uncoated apple slices. The quality variables evaluated were weight-loss, firmness, browning index, total phenolic content, total soluble solids, titratable acidity, respiration rate, microbial analysis, and sensory evaluation. All coatings improved the preservation and sensorial quality variables of Golden Delicious apples; however, although the CT1-chitosan-based coating was capable of extending the shelf-life of minimally processed apple, it demonstrated less sensorially favorable scores for flavor, odor, and overall acceptance attributes.

The energy crisis and the exacerbation of climate change, along with the associated geopolitical tensions, including the war in Ukraine, are accelerating the energy transition in Europe. A transition from fossil energy sources to renewable energy sources that have a low Energy Return Rate, involves, among many other issues, the use of wide areas to locate the necessary infrastructure for production, transport and storage, altering territories with agricultural, cultural and ecological values. This process is based on the deployment of renewable energy megaprojects in peripheric areas of the continent, mostly in the southern states creating a wide range of social conflicts and resistances. We analyse this process in the case study of the province of Granada, a peripheric territory of south-east Spain considering the category of energy colonialism and the six dimensions that characterise it, arguing that this is a proper approach to address internal colonialism related to the corporate energy transition. We also want to demonstrate the importance of using participatory methodologies for this analysis, so we have developed an online survey, semi-structured interviews and participatory cartography workshops, always focusing on the citizens and stakeholders who are resisting the deployment of renewable energy megaprojects in the province of Granada. The obtained results allow us to confirm the necessity of using participatory methodologies and the colonial aspect of this deployment, including the characteristics of social resistance, the territorial impacts, the land-grabbing process and the inequalities in the production, distribution and use of energy. We conclude with the need to articulate a decolonial energy transition where participatory methods constitute a fundamental tool both to attend the resistances and to build the alternatives. [ABSTRACT FROM AUTHOR]

A species new to science of a miniature orchid, endemic to the humid Pacific lowland, Municipality of Buenaventura (Valle del Cauca, Colombia), is described and illustrated. Ophidion erectilabrum sp. nov. is morphologically similar to O. alphonsianum, but the new species is recognized by the orbicular leaves (vs. elliptic), the erect inflorescence, longer than the leaves (vs. descending, shorter than the leaves), and the abruptly upward curved epichile (vs. flat). Because of the different proposals in the circumscription of Phloeophila s.l., we performed a new phylogenetic analysis to assess the most appropriate genus to place the new species, and discuss the phylogenetic position of Luerella, Ophidion, and Phloeophila based on all currently available data from nrITS and matK and recent studies using high-throughput sequencing. Although the three genera are supported as monophyletic groups, we recovered unresolved relationships and discordant topologies among them using only these two molecular markers. Therefore, we describe this species in Ophidion because of the morphological differences between Luerella and Phloeophila and because the grouping of Phloeophila s.l. lacks diagnostic features, and is yet to be supported by molecular analysis. [ABSTRACT FROM AUTHOR]