971 resultados para Factor (fgf)-2


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Recientemente ha existido un creciente interés por la sabiduría en el contexto organizacional estratégico, como respuesta a los retos que enfrentan las empresas. El presente estudio documental, tuvo como propósito comprender desde los planteamientos de Sternberg, Staudinger y Baltes, las formas en que se manifiesta la sabiduría en el liderazgo organizacional. Para cumplir con este objetivo se revisaron 29 documentos y el análisis se centró en la exploración de tres categorías: la edad, los componentes y facilitadores y los niveles de sabiduría. Al contrastar las teorías con las categorías se encontró que: 1) la edad cronológica no es un factor determinante para considerar a una persona sabia o no, pero si es un factor necesario. 2) entre los componentes y facilitadores de la sabiduría se encuentran: excelente juicio, visión, inteligencia y creatividad, acompañados de carácter y habilidad en la toma de decisiones y la planeación estratégica y 3) en la categoría niveles, se identificaron: tipos de falacias en las que pueden incurrir los gerentes, tipos de gerentes, entre ellos el sabio y, grado de conocimientos diferentes: unos relacionados con la sabiduría y otros sabios propiamente dichos. En conclusión, en la mayoría de los casos la sabiduría es considerada una cumbre del desarrollo humano, sea en el contexto personal o en el organizacional.

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Tratar de describir las variables sociodemográficas que se relacionan con aspectos psicopatológicos y su distribución geográfica en la Comunidad Autónoma Canaria. . Participaron un total de 1564 personas de la población general. De ellos, 744 eran varones y 818 mujeres. La edad media fue de 36,03 años y el rango entre 18 y 65 años. La muestra fue representativa d ela Comunidad Autónoma Canaria, estratificada por sexo, edad, municipio e isla de residencia. . Las variables estudiadas fueron: 1. Lugar de nacimiento y/o residencia (municipio urbano, municipio rural). 2. Isla de nacimiento y/o residencia (Gran Canaria, Tenerife, La Palma, La Gomera, El Hierro, Fuerteventura y Lanzarote). 3. Sexo (varón, mujer). 4. Estado civil (soltero/a, casado/a, viudo/a, separado/divorciado, en convivencia). 5. Profesión. 6. Condiciones de trabajo. 7. Nivel cultural. 8. Emigración fuera de las islas. 9. Edad. Previo al inicio de la investigación se realizó un estudio piloto para hallar una aproximación a la prevalencia, que permitiera, por un lado, calcular el número de personas que deberían componer la muestra representativa y, por otro lado, tomar decisiones sobre los instrumentos que se iban a utilizar. El paso siguiente fue entrenar a 7 evaluadores, homogeneizando los criterios en la administración d ela batería de los cuestionarios. Los datos codificados, procesados y analizados por el programa computarizado estadístico SPSS/pc+. . Para la evaluación se ha utilizado: un 'protocolo de variables sociodemográficas', los cuestionarios de paranoidismo y de síntomas hipomaníacos de De las Heras (1993), el cuestionario AD sobre dependencia al consumo de sustancias tóxicas (García Medina, en fase experimental), y el cuestionario GHQ-28 de Golberg, adaptado a la población española por Lobo, Pérez Echevarría y Artal (1986). . Se presenta un primer bloque de seis conclusiones que versan sobre propiedades psicométricas de los instrumentos utilizados en la investigación para operativizar el constructo de psicopatología a fin de hacerlo apresable y medible. por la extensión de dichas conclusiones no se pueden recoger en el presente resumen. Por lo que se refiere a la relación entre 'síntomas psicológicos y variables demográficas' en la Comunidad Autónoma Canaria, los resultados se resumen en las siguientes conclusiones: 1. En cuanto al sexo, se observa que las mujeres presentan mayor número y/o intensidad de síntomas que los hombres en depresión y/o ansiedad, así como en el factor somático. 2. Edad: como grupo de riesgo con síntomas de depresión aparecen las personas más jóvenes. Parte de esta variabilidad es atribuible al estado civil. En dependencia al consumo de sustancias tóxicas parecen ser las personas con edad intermedia (26 a 41 años) las que tienen mayor tendencia a presentar estos síntomas. 3. Estado civil: Los resultados señalan como grupo de riesgo de síntomas de depresión y/o ansiedad a las personas que han perdido su pareja, particularmente por muerte. Mientras que se aleja de ese perfil, parece estar más protegido, el grupo que convive en pareja, sin estar oficialmente casados. Además, las personas que viven en pareja tienen menor riesgo de padecer síntomas de depresión. 4. Municipio de residencia en el medio urbano manifiestan más síntomas psicopatológicos. 5. Isla de residencia: Los resultados muestran a los habitantes de las islas capitalinas con mayor número y/o mayor puntuación en síntomas de ansiedad, depresión, hipomanía y optimismo exagerado. 6. Profesión: se ha hallado mayor riesgo en el factor somático entre las amas de casa. En dependencia al consumo de sustancias tóxicas, el pertenecer a este último grupo aparece como un factor protector. En este tipo de síntomas, los que mayor riesgo presentan son los profesionales y obreros cualificados. 7. Las condiciones laborales más precarias (parados) se presentan como un factor de riesgo de síntomas de dependencia física al consumo de sustancias tóxicas. 8. El nivel cultural es el factor con mayor variabilidad sintomatológica. Los grupos con mayor riesgo de síntomas psicopatológicos de ansiedad, somático y de síntomas de paranoidismo son los que tienen menor instrucción educativa (leer y escribir). 10. Los factores de hiperactivación y dependencia psicopatológica al consumo de sustancia tóxicas no obtienen variabilidad significativa, entre distintos grupos de las variables sociodemográficas tratadas en este estudio. 11. El poder discriminativo de las nueve variables sociodemográficas, aunque significativo estadísticamente, no es sobresaliente, pero sí aceptable. Carcaterizándose, sociodemográficamente, las personas con síntomas significativos de hipomanía/manía por ser: jóvenes, residentes en las islas capitalinas, nivel cultural medio-alto, varón, residentes en las ciudades y en condiciones laborales inestables..

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At the end of the last century, a model to explain clinical observations related to the mandibular growth was developed. According to it, the lateral pterigoid muscle (LPM) was one of the main modulators of the differentiation of mesenquimal cells inside the condyle to condroblasts or osteoblasts, and therefore of the growth of the mandibular condilar cartilage (CCM). The main components of the model were the humoral and the mechanical. Nowadays, the humoral would include growth factors such as IGF-I, FGF-2 and VEGF, which seem to be involved in mandibular growth. Since skeletal muscle can secrete these growth factors, there is a possibility that LPM modulates the growth of CCM by a paracrine or endocrine mechanism. The mechanical component derived from the observations that both the blood flow inside the temporomandibular joint (ATM) and the action of the retrodiscal pad on the growth of the CCM, depend, in part, on the contractile activity of the LPM. Despite the fact that there are some results suggesting  hat LPM is activated under conditions of mandibular protrusion, there is no full agreement on whether this can stimulate the growth of CCM. In this review, the contributions and limitations of the works related to mandibular growth are discussed and a model which integrates the available information to explain the role of the LPM in the growth of the CCM is proposed.

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Aumentar el potencial de aprendizaje y la capacidad de reflexión en aquellos alumnos que fracasan en la EGB a través de la metodología de R. Feuerstein. Ésta va dirigida a cambiar la estructura cognitiva de los individuos tratados para que sean sensibles a los estímulos y experiencias que se les presenten, aprendan a aprender, a ser lo menos impulsivos posible y a hacer de la reflexión un hábito constante en ellos. La experimentación se ha realizado en: dos centros públicos de EGB: XXV Años de Paz y Narciso Alonso Cortés; un centro de Educación Especial: Centro Provincial de Educación Especial de Buecillo; Colegio privado Ave María de las Madres Carmelitas; un centro privado de diagnóstico y orientación (CEMCO). Formación de grupos experimentales y control, midiendo su homogeneidad. La selección de ellos se ha hecho de acuerdo con el criterio de ordenación de las muestras estratificadas (siendo los estratos los colegios o cursos a los cuales pertenecen los sujetos). Dicha ordenación se ha realizado lexicográficamente, de acuerdo con los tests: factor G, y los subtests E, R y V del PMA, y por este orden de prioridad. Una vez hecha la ordenación, se han seleccionado para el grupo experimental y control los pares o impares tomados al azar. Para contrastar la homogeneidad de los grupos experimental y control, se ha elegido la medida complementaria de diferencias significativas en cada una de las pruebas a las que han sido sometidos los sujetos: TEA 1 y 2, factor G 2, PMA, prueba de comprensión lectora de dos primeros instrumentos de la metodología de R. Feuerstein: organización de puntos y orientación en el espacio. Las actividades realizadas con los distintos grupos control han sido juegos y entretenimientos que exigen pensar, variando estos según las características de los grupos. Debido al poco tiempo de aplicación de la metodología, el enriquecimiento instrumental de Reuven Feuerstein, no pueden valorarse cuantitativamente los resultados, esperando a hacerlo al final de los dos años de experimentación directa del método. Relativo al trabajo de experimentación: necesidad de aumentar el personal docente para hacer trabajos experimentales, crear departamentos de Psico-pedagogía en centros de EGB e instalar en ellos equipos multiprofesionales. En cuanto a la metodología experimentada, el enriquecimiento instrumental del Reuven Feuerstein: reduce la impulsividad, los instrumentos de trabajo del método son motivadores, su metodología de impulsar a descubrir hace al alumno más capaz, crece y se autoafirma, desarrolla los procesos cognitivos, se puede aplicar el trabajo a la vida diaria, el profesor y su metodología son fundamentales, los grupos reducidos favorecen la interrelación.

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Determinar la estructura factorial de la tradicionalmente denominada comprensión verbal o, en términos más generales, de la inteligencia general cristalizada. Obtener una batería de tests basada en contenidos verbales, fiable y válida para la predicción del rendimiento académico en educación primaria y secundaria obligatoria. Hipótesis: 'La aptitud tradicionalmente conocida como comprensión verbal no es una aptitud simple, sino que es un constructo de naturaleza multidimensional, que puede descomponerse en cuatro factores que, a su vez, están muy correlacionados, mostrando además la unicidad de dicha aptitud. Los factores son los siguientes: 1. Conocimiento y manejo de vocabulario o factor semántico. 2. Conocimiento de estructuras ligüísticas. 3. Clausura verbal. 4. Razonamiento verbal o relaciones verbales'. Estudio 1: 356 estudiantes de BUP y COU de Cantabria y Granada; Estudio 2: Alumnos de cuarto, quinto, séptimo, octavo de EGB y de primero de BUP; Estudio 3; 211 alumnos de quinto, sexto, y séptimo de EGB y 183 sujetos de octavo de EGB. El estudio se estructura en tres fases sucesivas: 1. Inteligencia verbal en estudiantes de BUP y COU; se aplica una batería de tests que proviene de investigaciones previas. A través de análisis factoriales y de conglomerados se establece la estructura factorial de la comprensión verbal. Las variables utilizadas son 3 factores: lingüístico, de razonamiento y semántico. 2. Comprensión lingüística en escolares de 9 a 15 años; se construyen 64 pruebas con 2 diferentes niveles de dificultad. Se analizan los elementos de cada test en el marco de la Teoría de Respuesta al item (TRI). Las variables empleadas son: comprensión semántica, razonamiento inductivo-deductivo, lingüístico, rapidez perceptiva o de clausura. 3. Propiedades psicométricas de los tests de las baterías; la batería definitiva se compone de 28 tests en el nivel elemental y de 29 tests en el nivel medio. Analizan las pruebas por los procedimientos de la teoría clásica y de la TRI, ecuaciones de regresión y análisis factoriales. Las variables consideradas son los siguientes factores: semántico, razonamiento inductivo y deductivo, lingüístico, rapidez-clausura verbal, memoria inmediata. Correlacciones, análisis factorial no lineal, programa Noharm, índice de dificultad, varianza, índice de discriminación, coeficiente alpha, programa Reliability, respuestas de elección múltiple, programa BILOG 3.0, validez de criterio, programas correlations, correlaciones de Pearson, tablas, validez predictiva, procedimiento STEPWISE, programa SPSS-REGRESSION, programa LISREL. Los cuatro factores considerados en la hipótesis de partida, en relación con la estructura factorial de la comprensión verbal, aparecen claramente en el nivel medio, pero no en el nivel elemental, donde la estructura resultante es más compleja. Los análisis realizados permiten confirmar que la batería de pruebas elaborada es un instrumento fiable y válido para el diagnóstico de la inteligencia verbal. En resumen, los resultados apuntan que la comprensión verbal es un factor multidimensional, que puede considerarse como representativo de la aptitud general cristalizada.

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Tropical Cyclones (TC) under different climate conditions in the Northern Hemisphere have been investigated with the Max Planck Institute (MPI) coupled (ECHAM5/MPIOM) and atmosphere (ECHAM5) climate models. The intensity and size of the TC depend crucially on resolution with higher wind speed and smaller scales at the higher resolutions. The typical size of the TC is reduced by a factor of 2.3 from T63 to T319 using the distance of the maximum wind speed from the centre of the storm as a measure. The full three dimensional structure of the storms becomes increasingly more realistic as the resolution is increased. For the T63 resolution, three ensemble runs are explored for the period 1860 until 2100 using the IPCC SRES scenario A1B and evaluated for three 30 year periods at the end of the 19th, 20th and 21st century, respectively. While there is no significant change between the 19th and the 20th century, there is a considerable reduction in the number of the TC by some 20% in the 21st century, but no change in the number of the more intense storms. Reduction in the number of storms occurs in all regions. A single additional experiment at T213 resolution was run for the two latter 30-year periods. The T213 is an atmospheric only experiment using the transient Sea Surface Temperatures (SST) of the T63 resolution experiment. Also in this case, there is a reduction by some 10% in the number of simulated TC in the 21st century compared to the 20th century but a marked increase in the number of intense storms. The number of storms with maximum wind speeds greater than 50ms-1 increases by a third. Most of the intensification takes place in 2 the Eastern Pacific and in the Atlantic where also the number of storms more or less stays the same. We identify two competing processes effecting TC in a warmer climate. First, the increase in the static stability and the reduced vertical circulation is suggested to contribute to the reduction in the number of storms. Second, the increase in temperature and water vapor provide more energy for the storms so that when favorable conditions occur, the higher SST and higher specific humidity will contribute to more intense storms. As the maximum intensity depends crucially on resolution, this will require higher resolution to have its full effect. The distribution of storms between different regions does not, at first approximation, depend on the temperature itself but on the distribution of the SST anomalies and their influence on the atmospheric circulation. Two additional transient experiments at T319 resolution where run for 20 years at the end of the 20th and 21st century, respectively using the same conditions as in the T213 experiments. The results are consistent with the T213 study. The total number of tropical cyclones were similar to the T213 experiment but were generally more intense. The change from the 20th to the 21st century was also similar with fewer TC in total but with more intense cyclones.

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The creation of OFDM based Wireless Personal Area Networks (WPANs) has allowed the development of high bit-rate wireless communication devices suitable for streaming High Definition video between consumer products, as demonstrated in Wireless-USB and Wireless-HDMI. However, these devices need high frequency clock rates, particularly for the OFDM, FFT and symbol processing sections resulting in high silicon cost and high electrical power. The high clock rates make hardware prototyping difficult and verification is therefore very important but costly. Acknowledging that electrical power in wireless consumer devices is more critical than the number of implemented logic gates, this paper presents a Double Data Rate (DDR) architecture for implementation inside a OFDM baseband codec in order to reduce the high frequency clock rates by a complete factor of 2. The presented architecture has been implemented and tested for ECMA-368 (Wireless- USB context) resulting in a maximum clock rate of 264MHz instead of the expected 528MHz clock rate existing anywhere on the baseband codec die.

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The creation of OFDM based Wireless Personal Area Networks (WPANs) has allowed high bit-rate wireless communication devices suitable for streaming High Definition video between consumer products as demonstrated in Wireless- USB. However, these devices need high clock rates, particularly for the OFDM sections resulting in high silicon cost and high electrical power. Acknowledging that electrical power in wireless consumer devices is more critical than the number of implemented logic gates, this paper presents a Double Data Rate (DDR) architecture to reduce the OFDM input and output clock rate by a factor of 2. The architecture has been implemented and tested for Wireless-USB (ECMA-368) resulting in a maximum clock of 264MHz instead of 528MHz existing anywhere on the die.

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Development of external genitalia in mammalian embryos requires tight coordination of a complex series of morphogenetic events involving outgrowth, proximodistal and dorsoventral patterning, and epithelial tubulogenesis. Hypospadias is a congenital defect of the external genitalia that results from failure of urethral tube closure. Although this is the second most common birth defect in humans, affecting one in every 250 children, the molecular mechanisms that regulate morphogenesis of the mammalian urethra are poorly understood. We report that mice lacking the IIIb isoform of fibroblast growth factor receptor 2 (Fgfr2) exhibit severe hypospadias. Urethral signaling regions, as indicated by Shh and Fgf8 expression, are established in Fgfr2-IIIb null mice; however, cell proliferation arrests prematurely and maturation of the urethral epithelium is disrupted. Fgfr2-IIIb(-/-) mutants fail to maintain the progenitor cell population required for uroepithelial renewal during tubular morphogenesis. In addition, we show that antagonism of the androgen receptor (AR) leads to loss of Fgfr2-IIIb and Fgf10 expression in the urethra, and an associated hypospadias phenotype, suggesting that these genes are downstream targets of AR during external genital development. Genitourinary defects resulting from disruption of AR activity, by either genetic or environmental factors, may therefore involve negative regulation of the Fgfr2 pathway. This represents the first example of how the developing genitourinary system integrates cues from systemically circulating steroid hormones with a locally expressed growth factor pathway.

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The rovibration partition function of CH4 was calculated in the temperature range of 100-1000 K using well-converged energy levels that were calculated by vibrational-rotational configuration interaction using the Watson Hamiltonian for total angular momenta J=0-50 and the MULTIMODE computer program. The configuration state functions are products of ground-state occupied and virtual modals obtained using the vibrational self-consistent field method. The Gilbert and Jordan potential energy surface was used for the calculations. The resulting partition function was used to test the harmonic oscillator approximation and the separable-rotation approximation. The harmonic oscillator, rigid-rotator approximation is in error by a factor of 2.3 at 300 K, but we also propose a separable-rotation approximation that is accurate within 2% from 100 to 1000 K. (C) 2004 American Institute of Physics.

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A Kriging interpolation method is combined with an object-based evaluation measure to assess the ability of the UK Met Office's dispersion and weather prediction models to predict the evolution of a plume of tracer as it was transported across Europe. The object-based evaluation method, SAL, considers aspects of the Structure, Amplitude and Location of the pollutant field. The SAL method is able to quantify errors in the predicted size and shape of the pollutant plume, through the structure component, the over- or under-prediction of the pollutant concentrations, through the amplitude component, and the position of the pollutant plume, through the location component. The quantitative results of the SAL evaluation are similar for both models and close to a subjective visual inspection of the predictions. A negative structure component for both models, throughout the entire 60 hour plume dispersion simulation, indicates that the modelled plumes are too small and/or too peaked compared to the observed plume at all times. The amplitude component for both models is strongly positive at the start of the simulation, indicating that surface concentrations are over-predicted by both models for the first 24 hours, but modelled concentrations are within a factor of 2 of the observations at later times. Finally, for both models, the location component is small for the first 48 hours after the start of the tracer release, indicating that the modelled plumes are situated close to the observed plume early on in the simulation, but this plume location error grows at later times. The SAL methodology has also been used to identify differences in the transport of pollution in the dispersion and weather prediction models. The convection scheme in the weather prediction model is found to transport more pollution vertically out of the boundary layer into the free troposphere than the dispersion model convection scheme resulting in lower pollutant concentrations near the surface and hence a better forecast for this case study.

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The hierarchical and "bob" (or branch-on-branch) models are tube-based computational models recently developed for predicting the linear rheology of general mixtures of polydisperse branched polymers. These two models are based on a similar tube-theory framework but differ in their numerical implementation and details of relaxation mechanisms. We present a detailed overview of the similarities and differences of these models and examine the effects of these differences on the predictions of the linear viscoelastic properties of a set of representative branched polymer samples in order to give a general picture of the performance of these models. Our analysis confirms that the hierarchical and bob models quantitatively predict the linear rheology of a wide range of branched polymer melts but also indicate that there is still no unique solution to cover all types of branched polymers without case-by-case adjustment of parameters such as the dilution exponent alpha and the factor p(2) which defines the hopping distance of a branch point relative to the tube diameter. An updated version of the hierarchical model, which shows improved computational efficiency and refined relaxation mechanisms, is introduced and used in these analyses.

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In situ precipitation measurements can extremely differ in space and time. Taking into account the limited spatial–temporal representativity and the uncertainty of a single station is important for validating mesoscale numerical model results as well as for interpreting remote sensing data. In situ precipitation data from a high resolution network in North-Eastern Germany are analysed to determine their temporal and spatial representativity. For the dry year 2003 precipitation amounts were available with 10 min resolution from 14 rain gauges distributed in an area of 25 km 25 km around the Meteorological Observatory Lindenberg (Richard-Aßmann Observatory). Our analysis reveals that short-term (up to 6 h) precipitation events dominate (94% of all events) and that the distribution is skewed with a high frequency of very low precipitation amounts. Long-lasting precipitation events are rare (6% of all precipitation events), but account for nearly 50% of the annual precipitation. The spatial representativity of a single-site measurement increases slightly for longer measurement intervals and the variability decreases. Hourly precipitation amounts are representative for an area of 11 km 11 km. Daily precipitation amounts appear to be reliable with an uncertainty factor of 3.3 for an area of 25 km 25 km, and weekly and monthly precipitation amounts have uncertainties of a factor of 2 and 1.4 when compared to 25 km 25 km mean values.

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The intensity and distribution of daily precipitation is predicted to change under scenarios of increased greenhouse gases (GHGs). In this paper, we analyse the ability of HadCM2, a general circulation model (GCM), and a high-resolution regional climate model (RCM), both developed at the Met Office's Hadley Centre, to simulate extreme daily precipitation by reference to observations. A detailed analysis of daily precipitation is made at two UK grid boxes, where probabilities of reaching daily thresholds in the GCM and RCM are compared with observations. We find that the RCM generally overpredicts probabilities of extreme daily precipitation but that, when the GCM and RCM simulated values are scaled to have the same mean as the observations, the RCM captures the upper-tail distribution more realistically. To compare regional changes in daily precipitation in the GHG-forced period 2080-2100 in the GCM and the RCM, we develop two methods. The first considers the fractional changes in probability of local daily precipitation reaching or exceeding a fixed 15 mm threshold in the anomaly climate compared with the control. The second method uses the upper one-percentile of the control at each point as the threshold. Agreement between the models is better in both seasons with the latter method, which we suggest may be more useful when considering larger scale spatial changes. On average, the probability of precipitation exceeding the 1% threshold increases by a factor of 2.5 (GCM and RCM) in winter and by I .7 (GCM) or 1.3 (RCM) in summer.

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The Sun's open magnetic field, magnetic flux dragged out into the heliosphere by the solar wind, varies by approximately a factor of 2 over the solar cycle. We consider the evolution of open solar flux in terms of a source and loss term. Open solar flux creation is likely to proceed at a rate dependent on the rate of photospheric flux emergence, which can be roughly parameterized by sunspot number or coronal mass ejection rate, when available. The open solar flux loss term is more difficult to relate to an observable parameter. The supersonic nature of the solar wind means open solar flux can only be removed by near-Sun magnetic reconnection between open solar magnetic field lines, be they open or closed heliospheric field lines. In this study we reconstruct open solar flux over the last three solar cycles and demonstrate that the loss term may be related to the degree to which the heliospheric current sheet (HCS) is warped, i.e., locally tilted from the solar rotation direction. This can account for both the large dip in open solar flux at the time of sunspot maximum as well as the asymmetry in open solar flux during the rising and declining phases of the solar cycle. The observed cycle-to-cycle variability is also well matched. Following Sheeley et al. (2001), we attribute modulation of open solar flux by the degree of warp of the HCS to the rate at which opposite polarity open solar flux is brought together by differential rotation.