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Concentrating solar power (CSP) is one of the most promising environmentally-friendly sources of energy for meeting global energy demands. One line of research intended to improve this kind of solar plants involves increasing the efficiency of the heat transfer fluid (HTF) used, one option being the use of nanofluids. Consequently, this study involves a methodology based on liquid phase exfoliation to prepare stable nanofluids based on 2D MoSe2. A surfactant was used to modify the ratio of the components of the fluid's surface tension in order to obtain a stable nanofluid. Five nanofluids were prepared based on MoSe2 nanosheets, Dowtherm A heat transfer fluid and the Triton X-100 surfactant. The stability of the nanofluids was analysed for a month. Lastly, their thermal properties were characterized. The best nanofluid presented improvements of 7% in isobaric specific heat, 4% in diffusivity and 11% in thermal conductivity. Therefore, these nanofluids would appear to provide a good starting point for creating an alternative to the conventional HTFs used in thermosolar plants. The study highlights the importance of optimizing the parameters of the ratio of the surface tension components, the kind of surfactant added and the methodology used to prepare the nanofluid.

This letter presents a method for the synthesis of copper-doped TiO2 nanoparticles. The semiconductors synthesized were characterized in order to know the composition, crystalline structure, the band gap energy, etc. The nanoparticles obtained have a very low band gap (1.6 eV for 7.5% Cu-doping) compared with the values reported in the literature. The results obtained revealed that internal doping of the TiO2 structure is produced, and that the predominant crystalline phase is anatase. The semiconductors synthesized would be of great use in photocatalytic and photovoltaic applications due to the high specific surface and the low band gap energy values.

This study shows an analysis of the stability of nanofluids based on a eutectic mixture of diphenyl oxide and biphenyl, which is used as a heat transfer fluid (HTF) in concentrating solar energy, and NiO nanoparticles. Two surfactants are used to analyse the stability of the nanofluids: benzalkonium chloride (BAC) and 1-octadecanethiol (ODT). From an experimental perspective, the stability is analysed by means of UV/Vis spectroscopy, particle size measurements through the dynamic light-scattering technique, and ζ-potential measurements. The results show that the stability of the nanofluids improves with the use of BAC. DFT calculations are performed to understand the role played by the surfactants. The interaction of the surfactants with both the fluid and the NiO (100) surface is studied. Quantum theory of atoms in molecules (QTAIM) analysis shows that hydrogen bridge interactions favour the stability of the fluid-surfactant mixture. The more stabilising NiO-surfactant interaction involves the Ni-H interaction of the -SH and -CH3 groups of ODT and BAC. Also, nanofluids with BAC are favoured over those with ODT, which is in agreement with experimental results. The structural and electronic effects of incorporating the surfactant onto the NiO (100) surface are shown by using electron localisation function analysis, the non-covalent interaction index and projected density of states.

To compare the effectiveness of pulse oximetry and fetal electrocardiography in the management of labor with nonreassuring fetal heart rate (NRFHR).This randomized experimental study consisted of two arms. In group 1 we used pulse oximetry and in group 2 we used STAN® technology. The participants in each group were 90 pregnant women with a full-term singleton fetus in cephalic presentation and cardiotocographic tracings compatible with NRFHR. We compared the following variables: rate of cesarean delivery, indications for operative delivery due to NRFHR, and repercussions on the newborn's acid-base status.The two groups differed significantly in the mode of delivery, with a cesarean delivery rate of 47.6% in group 1 vs. 30% in group 2 (p=0.032). The groups did not differ in the indications for ending labor due to NRFHR (62% vs. 61%, NS). In terms of neonatal outcomes, the 1-min Apgar score was 6 or lower in 17.8% of the group 1 neonates vs. 4.44% of the group 2 neonates (p0.001). The groups also differed significantly in umbilical cord vein pH (7.23 vs. 7.27) and pCO₂ (57.27 vs. 46.86) at birth.Fetal electrocardiography with the STAN® 21 system was more effective in detecting good fetal status and thus in identifying cases in which labor could proceed safely. Intrapartum surveillance with the STAN® 21 system reduced the rate of emergency cesarean delivery.

TiO2 doping has been widely used in photocatalysis and photovoltaic cells to improve the performance of this semiconductor. This paper studies the use of copper as a dopant in TiO2 in dye-sensitized solar cells (DSSC), analysing the effect on the photovoltaic properties of the cells of different concentrations of copper incorporated into the semiconductor. The copper-doped TiO2 semiconductor was characterized with several instrumental techniques, including X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES), scanning transmission electron microscopy (STEM), and UV–Vis spectroscopy in order to know its structure, composition and band gap energies with different concentrations of the dopant. An analysis was also performed of the variations in open-circuit voltage depending on the concentration of copper. This showed that the presence of copper in DSSCs made with a standard configuration – using a ruthenium complex (N3) as a dye and the redox pair as the electrolyte with 3-methoxypropionitrile as a solvent – leads to improvements of up to 10% in the open-circuit voltage of DSSCs.

Este texto se ocupa del papel que la representación del cuerpo humano adquiere en el net.art. Por un lado, considera que el cuerpo humano ha sido descorporeizado y proyectado en el no lugar del espacio telemático, enfrentado así a las tendencias de rematerialización del cuerpo, como el arte carnal y el body art, y, por otra, parte considera que incluso en esta esfera ciberespacial el cuerpo de Internet se ve como una prolongación del arte carnal, según los trabajos de Orlan y Tomic. La construcción del género y el trabajo artístico de las mujeres en la red es otro de los objetivos que este texto pone de manifiesto como vinculación de mujeres y nuevas tecnologías en el contexto artístico del net.art., This text deals with the role that the representation of the human body acquired in net.art. On the one hand, considers that the human body has been disembodied and projected in the nowhere of telematic space, thus faced to the rematerialization trends of the body, as the carnal art and body art, and by the other hand considers that even in this cyberspace area the Internet´s body is seen as an extension of carnal art, depending on the work of Orlan and Tomic. The construction of gender and women's artwork in the network is another objective that this text shows as linking between women and new technologies in the artistic context of net.art.

Resumen Objetivo Analizar las peculiaridades quirurgicas asociadas al tratamiento por via laparoscopica del quiste dermoide ovarico. Se estudian, igualmente, los factores asociados a la rotura intraoperatoria del quiste y su trascendencia clinica. Material y metodos Se realizo un estudio retrospectivo de 131 quistes dermoides intervenidos por via laparoscopica en el Hospital Universitario Virgen de las Nieves desde enero de 2000 hasta diciembre de 2008. Resultados La edad media de las pacientes fue de 32,4 anos. El tamano medio del quiste fue de 63,8 mm. En el 62,6% de los casos se pudo realizar cirugia conservadora (quistectomia). Solo 2 pacientes precisaron reintervencion por problemas hemorragicos. La estancia media fue de 1,6 dias. La rotura intraoperatoria del quiste ocurrio con mas frecuencia cuando se practico quistectomia. No hubo ningun caso de peritonitis. Conclusiones La laparoscopia es la tecnica de eleccion en el tratamiento quirurgico del quiste dermoide de ovario. Las complicaciones son minimas y la recuperacion rapida. Si se produce la rotura intraoperatoria del quiste no suele tener trascendencia clinica alguna.

Objective: To review the characteristics of breast cancer in young women. Material and methods: The scientific literature was reviewed, indicating the etiological factors, diagnostic methods and treatment options, with special reference to the factors that can concur in young patients such as premature menopause, loss of fertility, pregnancy after breast cancer and breast cancer during pregnancy. Results: Importantly, breast cancer in young women is very rare but is on the increase. Tumors are larger in young women and have positive margins, making the disease more aggressive and leading to higher mortality. Diagnosis is more difficult than in older women and the triple test

Resumen El tratamiento conservador del cancer de endometrio (estadio I) es una opcion terapeutica para aquellas mujeres jovenes que aun no han cumplido sus deseos genesicos. Aunque los datos publicados sobre los resultados de las tecnicas de reproduccion asistida (TRA) tras el manejo conservador del cancer de endometrio son escasos, el pronostico no parece empeorar con el uso de estas. A continuacion, se describe el caso de una paciente de 29 anos, con esterilidad primaria, diagnosticada de cancer de endometrio en estadio IA, tratada con altas dosis de progesterona oral, y tras el cual quedo embarazada mediante TRA.

Resumen Objetivo Analizar la evolucion de las distintas modalidades en el tratamiento del embarazo ectopico durante los ultimos 9 anos. Material y metodos Se realizo un estudio retrospectivo de 355 casos de embarazo ectopico tratados en el Hospital Universitario Virgen de las Nieves durante el periodo comprendido entre 1998 y 2006. Se analizaron los cambios ocurridos en las distintas actitudes terapeuticas durante ese intervalo. Resultados El tratamiento medico se inicio en 139 (39,15%) casos, con una tasa de fracasos del 10,07%. El tratamiento quirurgico se realizo en 230 (60,85%) mujeres: en 121 casos se practico cirugia laparoscopica y en 109 una laparotomia. Conclusiones La cirugia laparoscopica es en la actualidad la primera opcion terapeutica en el embarazo ectopico tubarico, a pesar de que en estos ultimos anos se ha demostrado la seguridad y eficacia del tratamiento medico, posibilitando una actitud menos agresiva.

En este texto se caracteriza el llamado Feminismo Postmoderno y se presentan las posiciones teóricas de dos influyentes pensadoras contemporáneas en el ámbito de la filosofía de la ciencia desde una perspectiva feminista postmoderna. Haraway y Harding debaten en torno a la historia de la ciencia y sus sesgos androcéntricos, así como sobre el concepto identidad desde el paradigma cyborg. Dentro del paradigma postmoderno asumen la herencia postestructuralista y deconstruccionista y defienden la necesidad de una ciencia social crítica y autorreflexiva como modelo de todas las ciencias, pero tienen controversias en cuanto a la estructuración del espacio social generizado. Haraway entiende que el espacio social no es homogéneo, y que las tres dimensiones que detecta Harding: simbolismo genérico, división socio-sexual del trabajo y procesos de identidad individual generizada, se interceptan en múltiples dimensiones.

Este texto describe la evolución del cyborg desde la época griega hasta la actualidad, especialmente en el mundo del arte, a través del concepto de hibridación. Las fusiones corporales han estado presentes en la historia de la humani- dad desde la prehistoria a través de la figura de los teriántropos, en la mitología griega y más tarde en la obra de artistas como Arcimboldo, el Bosco y Leonardo. En la actualidad la figura del cyborg sigue manteniendo su representatividad en el arte con autores como Stelarc o P. Meste y adquiere una gran presencia en el mundo cinematográfico y en nuestro imaginario cotidiano. This text describes the evolution of cyborg from Greek times to the present, especially in the art world, through the concept of hybridization. Bodily fusions have been present in the history of mankind from prehistory through the therianthropes figure, in Greek mythology and later in the work of Renaissance artists such as Arcimboldo, Bosco and Leonardo. Today the figure of the cyborg retains its representation in art with artists such as Stelarc or P. Meste and acquires a strong presence in the film world and in our everyday imaginary

This paper presents the synthesis of the organic-inorganic hybrid perovskite, CH3NH3PbI3, doped in the Pb(2+) position with Sn(2+), Sr(2+), Cd(2+) and Ca(2+). The incorporation of the dopants into the crystalline structure was analysed, observing how the characteristics of the dopant affected properties such as the crystalline phase, emission and optical properties. XRD showed how doping with Sn(2+), Sr(2+) and Cd(2+) did not modify the normal tetragonal phase. When doping with Ca(2+), the cubic phase was obtained. Moreover, DR-UV-Vis spectroscopy showed how the band gap decreased with the dopants, the values following the trend Sr(2+)Cd(2+)Ca(2+)CH3NH3PbI3 ≈ Sn(2+). The biggest decrease was generated by Sr(2+), which reduced the CH3NH3PbI3 value by 4.5%. In turn, cathodoluminescence (CL) measurements confirmed the band gap obtained. Periodic-DFT calculations were performed to understand the experimental structures. The DOS analysis confirmed the experimental results obtained using UV-Vis spectroscopy, with the values calculated following the trend Sn(2+) ≈ Pb(2+)Cd(2+)Sr(2+) for the tetragonal structure and Pb(2+)Ca(2+) for the cubic phase. The electron localization function (ELF) analysis showed similar electron localizations for undoped and Sn(2+)-doped tetragonal structures, which were different from those doped with Sr(2+) and Cd(2+). Furthermore, when Cd(2+) was incorporated, the Cd-I interaction was strengthened. For Ca(2+) doping, the Ca-I interaction had a greater ionic nature than Cd-I. Finally, an analysis based on the non-covalent interaction (NCI) index is presented to determine the weak-type interactions of the CH3NH3 groups with the dopant and I atoms. To our knowledge, this kind of analysis with these hybrid systems has not been performed previously.

The aim of this study was to evaluate the effectiveness of the Bakri balloon in treating postpartum hemorrhage refractory to medical treatment. This retrospective study included 24 women with postpartum hemorrhage treated with a Bakri balloon as a conservative therapeutic option. The Bakri balloon was successful in controlling hemorrhage in 87.5% of the women. It was effective in all women with vaginal delivery (five of five) and in all women with uterine atony who did not respond to medical uterotonic treatment (eight of eight). Its ease of use and high effectiveness make the Bakri balloon a useful approach for the conservative management of acute postpartum hemorrhage. This device reduces bleeding, shortens the hospital stay and avoids the need for more aggressive procedures.

In this work, nanofluids were prepared using commercial Cu nanoparticles and a commercial high temperature-heat transfer Fluid (eutectic mixture of diphenyl oxide and biphenyl) as the base fluid, which is used in concentrating solar power (CSP) plants. Different properties such as density, viscosity, heat capacity and thermal conductivity were characterized. Nanofluids showed enhanced heat transfer efficiency. In detail, the incorporation of Cu nanoparticles led to an increase of the heat capacity up to 14%. Also, thermal conductivity was increased up to 13%. Finally, the performance of the nanofluids prepared increased up to 11% according to the Dittus-Boelter correlation. On the other hand, equilibrium molecular dynamics simulation was used to model the experimental nanofluid system studied. Thermodynamic properties such as heat capacity and thermal conductivity were calculated and the results were compared with experimental data. The analysis of the radial function distributions (RDFs) and the inspection of the spatial distribution functions (SDFs) indicate the important role that plays the metal-oxygen interaction in the system. Dynamic properties such as the diffusion coefficients of base fluid and nanofluid were computed according to Einstein relation by computing the mean square displacement (MSD).

Journal Article; BACKGROUND AND OBJECTIVES To analyze the frequency of complications during laparoscopic gynecologic surgery and identify associated risk factors. METHODS A descriptive observational study was performed between January 2000 and December 2012 and included all gynecologic laparoscopies performed at our center. Variables were recorded for patient characteristics, indication for surgery, length of hospital stay (in days), major and minor complications, and conversions to laparotomy. To identify risk factors and variables associated with complications, crude and adjusted odds ratios were calculated with unconditional logistic regression. RESULTS Of all 2888 laparoscopies included, most were procedures of moderate difficulty (adnexal surgery) (54.2%). The overall frequency of major complications was 1.93%, and that of minor complications was 4.29%. The level of technical difficulty and existence of prior abdominal surgery were associated with a higher risk of major complications and conversions to laparotomy. CONCLUSION Laparoscopic gynecologic surgery is associated with a low frequency of complications but is a procedure that is not without risk. Greater technical difficulty and prior surgery were factors associated with a higher frequency of complications. Yes

A good correlation was obtained between the electronic properties of Cu-doped anatase TiO2 by virtue of both physical chemistry characterization and theoretical calculations. Pure and Cu-doped TiO2 were synthesized. The composition, structural and electronic properties, and the band gap energy were obtained using several techniques. The method of synthesis used produces Cu-doped anatase TiO2, and XRD, XPS and Raman spectroscopy indicate that Cu atoms are incorporated in the structure by substitution of Ti atoms, generating a distortion of the structure and oxygen vacancies. In turn, the band gap energy of the synthesized samples decrease drastically with the Cu doping. Moreover, periodic density functional theory (DFT-periodic) calculations were carried out both to model the experimentally observed doped structures and to understand theoretically the experimental structures obtained, the formation of oxygen vacancies and the values of the band gap energy. From the analysis of density of states (DOS), projected density of states (PDOS) and the electron localization function (ELF) a decrease in the band gap is predicted upon increasing the Cu doping. Thus, the inclusion of Cu in the anatase structure implies a covalent character in the Cu–O interaction, which involves the appearance of new states in the valence band maximum with a narrowing in the band gap.

The aim of this study was to evaluate the effectiveness of the Bakri balloon in treating postpartum hemorrhage refractory to medical treatment. This retrospective study included 24 women with postpartum hemorrhage treated with a Bakri balloon as a conservative therapeutic option. The Bakri balloon was successful in controlling hemorrhage in 87.5% of the women. It was effective in all women with vaginal delivery (five of five) and in all women with uterine atony who did not respond to medical uterotonic treatment (eight of eight). Its ease of use and high effectiveness make the Bakri balloon a useful approach for the conservative management of acute postpartum hemorrhage. This device reduces bleeding, shortens the hospital stay and avoids the need for more aggressive procedures.

Background: High-intensity focused ultrasound (HIFU) is an energy-based medical technology with many clinical applications. A device under clinical investigation in the United States (LipoSonix; Medicis Technologies Corporation, Bothell, Washington) uses HIFU to reduce localized deposits of abdominal adipose tissue. Objectives: The authors describe the results from their clinical trial investigating the safety of this HIFU device in human patients. Methods: Over the course of three studies evaluating the safety of the HIFU device for ablating human subcutaneous adipose tissue (SAT), 152 healthy patients were treated with total HIFU energy doses of 47 to 331 J/cm2), including patients who presented for elective abdominoplasty and underwent treatment to areas identified for subsequent excision. The safety of each treatment regimen was confirmed before the energy levels were raised. Abdominoplasty was performed up to 14 weeks following the HIFU procedure, and a pathologist performed histopathological analyses of excised tissues. Safety evaluations included an assessment of clinical chemistry and hematology profiles, physical examinations, and adverse events. Results: Posttreatment ultrasound confirmed that the HIFU effects were limited to targeted SAT layers. Histopathology revealed well-demarcated disruption of adipocytes within the targeted SAT. Phagocytosis of released lipids and cellular debris occurred after 14 to 28 days. Phagocytized lipids underwent normal hepatic metabolism. Healing progressed normally and was 95% complete after eight to 14 weeks. Adverse events consisted primarily of temporary treatment discomfort, edema, erythema, dysesthesia, and ecchymosis. There were no changes in clinical laboratory parameters, and no serious device-related adverse events occurred. Optimal clinical outcomes were achieved with lower energy levels, which provided beneficial effects with the least amount of discomfort. Conclusions: HIFU appears to provide a safe means for removing and remodeling unwanted deposits of abdominal SAT.

Endocervical margins affected: 44 (15.7%): pre: 32 (14.2%) postmenopausal: 12 (21.8%). Reconizations 17 (6%): premenopausal: 14 (6.2%). Postmenopausal: 3 (5.4%). Hysterectomy postcone: 11 (3.9%): premenopausal: 3 (1.3%). Postmenopausal: 8 (14.5%) hysterectomy indications: 3 microinvasive, 3 persistence CIN 2–3 postcone, 5 Adeno insitu. Conclusions: We found no difference between the 2 groups of preand postmenopausal women in terms of cone histology and number of reconizations made. In the group of postmenopausal women, we found a large number of endocervical margins affected in the histological study of cone and this result would correspond to a greater number of endocervical lesions in menopausal than in premenopausal women. The other major difference was in the postcone hysterectomies related to high-grade lesions with large endocervical affection, which reach a rate of 15%.

This study presents the use of TiO2 nanoparticles with Tm as photoelectrodes in DSSCs. The nanoparticles were annealed at 1173 K and the predominant TiO2 phase was rutile. XRD and Raman spectroscopy revealed the presence of a crystalline pyrochlore phase of the mixed oxide Tm2Ti2O7. In turn, XPS confirmed the presence of Ti4+ and Tm3+, so the inclusion of Tm did not affect the oxidation state of the Ti. UV–Vis spectra showed that the presence of the pyrochlore phase led to new electronic states in the band gap. The use of the pyrochlore phase in the photoelectrode had a positive effect, improving the efficiency of the pure TiO2 cells. The efficiency increased by between 2.32% and 3.16% when pure TiO2 was replaced with a mixture of rutile TiO2 and pyrochlore Tm2Ti2O7, so the controlled use of a pyrochlore phase can produce good results in dye-sensitized solar cells. Another important effect of the pyrochlore phase was to increase the open-circuit voltage values by around 7% and can be explained by the flat band voltage values. The samples with Tm showed two flat band voltage values, which generated two possible electronic injection mechanisms in the cells.

This paper presents a non-conventional methodology and an instrumental system to measure the effect of temperature on the photovoltaic properties of solar cells. The system enables the direct measurement of the evolution of open-circuit voltage and short-circuit current intensity in relation to a continuously decreasing temperature. The system uses a high-intensity white light-emitting diode light source with low emissions of radiation in the infrared region of the electromagnetic spectrum, resulting in a reduced heating of the photovoltaic devices by the irradiation source itself. To check the goodness of the system and the methodology designed, several measurements were performed with monocrystalline silicon solar cells, dye-sensitized solar cells, and thin-film amorphous silicon solar cells, showing similar tendencies to those reported in the literature.

The village of Pegalajar, a town in the south of the Iberian Peninsula, in the province of Jaen (Andalusia, Spain), took life and body from an abundant source of water. From immemorial times, the water was harnessed and managed through a major hydro-agricultural system that allowed people to live in a barren and arid environment. In 1988 the government begins to succumb due to abusive extractions which were usurping uncontrolledly peripheral aquifer systems, and with it the image and life of the village. The territory of Pegalajar is presented, nevertheless, as a specific tissue of relationships that go beyond the human, including, in part of the local collective ideology, non-human elements of the environment. In this paper we present an analysis that brings us closer to understanding ecocosmologies that occur within the socio-ecosystem of the town, reflecting on the different ways in which people understand their environment and interacts with it