996 resultados para Cisma de 1130


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The three-dimensional fluorescence spectrum was used to detect the changes in dissolved organic substances from the cultured Skeletonema costatum, Alexandrium tamarense, Alexandrium mimutum, Scrippsiella trochodea, Prorocentrum donghaiense and Prorocentrum micans. The result indicates that all of the microalgaes can produce FDOM in the growth courses. Diatom such as Skeletonema costatum can produce humic-like FDOM. However dinoflagellate can produce protein-like FDOM at exponential growth phase. When the algae grows into decadency phase, the intensity of humic-like and protein-like fluorescence augments rapidly, which may be due to a mass of FDOM realeased by the old or dead cell fragmentation and the degradation of bacteria by using non-FDOM. The fluorescent intensity of Alexandrium tamarense, Alexandrium mimutum, Prorocentrum donghaiense and Prorocentrum micans can reduce at anaphase of decadency phase because of the degradation of bacteria and light. The same genus of algae can produce similar FDOM, for example: Alexandrium tamarense, and Alexandrium mimutum, Prorocentrum donghaiense and Prorocentrum micans, but the positions of the fluorescence peaks are different.

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系统报道黑边假龙胆(Gentianella azurea (Bunge) Holub)的胚胎发育过程,用以讨论假龙胆属长期存在争议的分类和系统发育问题。黑边假龙胆花药4室;药壁发育属双子叶型;绒毡层单型起源,细胞单核,属腺质绒毡层;花药壁表皮层宿存,药室内壁减缩。小抱子母细胞减数分裂为同时型,四分体的排列为四面体型;成熟花粉3-细胞型。子房为2心应,1室,减编的侧膜胎座,胚珠4列。薄珠心,单珠被,横生胚珠,大抱子母细胞减数分裂形成的4个大抱呈直列式排列,其中合点端的大抱子具功能。胚囊发育为蓼型。珠心冠原存在。极核在受精前融合为次生核,反足细胞宿存、分裂为8~12个、每个细胞均多核和异常膨大,反足细胞形成的吸器明显。雄蕊先熟。异花传粉,珠孔受精。花粉管进入胚囊时不破坏助细胞,助细胞宿存;一个精核和次生核的融合几乎发生在另一个精核和卵细胞核融合的同时。受精作用属于有丝分裂前配子体融合类型。胚乳为核型,胚乳核分裂同步,每核含2~3个核仁。胚胎发育为茄型酸浆Ⅰ变型。成熟种子中胚只发育至球形胚阶段。反足细胞在合子分裂之后才开始退化;在胚的发育过程中反足细胞在胚乳层之外形成一层染色深类似“外胚乳”的结构。和龙胆属比较,假龙胆属具有如下不同的特征:绒毡层单型起源,典型的腺质绒毡层,无“类胎座”和“横格”,单层;减缩侧墨胎座,胚珠4列,横生胚珠;珠心冠原存在;反足细胞异常膨大,形成内多倍体和多核,并在胚乳核之外形成一层类似“外胚乳”的结构;花粉管进入胚囊时不破坏助细胞;胚胎发育为茄型酸浆Ⅰ变型等。胚胎学研究结果表明假龙胆与龙胆属的亲缘关系较远,分类等级上作为一独立的属较合适,在系统位置上它与龙胆属可能不在同一条进化线上。

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Compared with the conventional P wave, multi-component seismic data can markedly provide more information, thus improve the quality of reservoir evaluation like formation evaluation etc. With PS wave, better imaging result can be obtained especially in areas involved with gas chimney and high velocity formation. However, the signal-to-noise of multi-component seismic data is normally lower than that of the conventional P wave seismic data, while the frequency range of converted wave is always close to that of the surface wave which adds to the difficulty of removing surface wave. To realize common reflection point data stacking from extracted common conversion point data is a hard nut to crack. The s wave static correction of common receiver point PS wave data is not easy neither. In a word, the processing of multi-component seismic data is more complicated than P wave data. This paper shows some work that has been done, addressing those problems mentioned above. (1) Based on the AVO feature of converted wave, this paper has realized the velocity spectrum of converted waves by using Sarkar’s generalized semblance method taking into account of AVO factor in velocity analysis. (2)We achieve a method of smoothly offset division normal method.Firstly we scan the stacking velocities in different offset divisions for a t0, secondly obtain some hyperbolas using these stacking velocities, then get the travel time for every trace using these hyperbolas; in the end we interpolate the normal move out between two t0 for every trace. (3) Here realize a method of stepwise offset division normal moveout.It is similar to the method of smoothly offset division normal moveout.The main difference is using quadratic curve, sixth order curve or fraction curve to fit these hyperbolas. (4)In this paper, 4 types of travel time versus distance functions in inhomogeneous media whose velocity or slowness varies with depth and vertical travel time have been discussed and used to approximate reflection travel time. The errors of ray path and travel time based on those functions in four layered models were analyzed, and it has shown that effective results of NMO in synthetic or real data can be obtained. (5) The velocity model of converted PS-wave can be considered as that of P -wave based on the ghost source theory, thus the converted wave travel time can be approximated by calculation from 4 equivalent velocity functions: velocity or slowness vary linearly with depth or vertical travel time. Then combining with P wave velocity analysis, the converted wave data can be corrected directly to the P-wave vertical travel time. The improvements were shown in Normal Move out of converted waves with numerical examples and real data. (6) This paper introduces the methods to compute conversion point location in vertical inhomogeneous media based on linear functions of velocity or slowness versus depth or vertical travel time, and introduce three ways to choose appropriate equivalent velocity methods, which are velocity fitting, travel time approximation and semblance coefficient methods.

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This study evaluated different techniques for surgically assisted rapid maxillary expansion (SARME) according to the type of transverse maxillary deficiency using computed tomography (CT). Six adult patients with bilateral transverse maxillary deficiencies underwent SARME. the patients were equally divided into three groups: Group I, maxillary atresia in both the anterior and posterior regions; Group II, greater maxillary atresia in the anterior region; and Group ill, increased maxillary atresia in the posterior region. in Group I, a subtotal Le Fort I osteotomy was used. in Group II, a subtotal Le Fort I osteotomy was used without pterygomaxillary suture disjunction. in Group III, a subtotal Le Fort I osteotomy was used with pterygomaxillary suture disjunction and fixation of the anterior nasal spine with steel wire. the midpalatal suture opening was evaluated preoperatively and immediately after the activation period using CT. for Group I, the opening occurred parallel to midpalatal suture; for Group II, the opening comprised a V-shape with a vertex on the posterior nasal spine; and for Group III, the opening comprised a V-shape with a vertex at the anterior nasal spine. the conclusion was that the SARME technique should be individualized according to the type of transverse maxillary deficiency.

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Sexton, J. (2008). From Art to Avant Garde? Television, Formalism and the Arts Documentary in 1960's Britain. In L. Mulvey and J. Sexton (Eds.), Experimental British Television (pp.89-105). Manchester: Manchester University Press. RAE2008

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Letter from Daniel Whedon to nephew, Daneil Avery Whedon. Dated December 11 1868.

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Transcranial magnetic stimulation (TMS) is a widely used, noninvasive method for stimulating nervous tissue, yet its mechanisms of effect are poorly understood. Here we report new methods for studying the influence of TMS on single neurons in the brain of alert non-human primates. We designed a TMS coil that focuses its effect near the tip of a recording electrode and recording electronics that enable direct acquisition of neuronal signals at the site of peak stimulus strength minimally perturbed by stimulation artifact in awake monkeys (Macaca mulatta). We recorded action potentials within ∼1 ms after 0.4-ms TMS pulses and observed changes in activity that differed significantly for active stimulation as compared with sham stimulation. This methodology is compatible with standard equipment in primate laboratories, allowing easy implementation. Application of these tools will facilitate the refinement of next generation TMS devices, experiments and treatment protocols.

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Microscopic plastic debris, termed “microplastics”, are of increasing environmental concern. Recent studies have demonstrated that a range of zooplankton, including copepods, can ingest microplastics. Copepods are a globally abundant class of zooplankton that form a key trophic link between primary producers and higher trophic marine organisms. Here we demonstrate that ingestion of microplastics can significantly alter the feeding capacity of the pelagic copepod Calanus helgolandicus. Exposed to 20 μm polystyrene beads (75 microplastics mL–1) and cultured algae ([250 μg C L–1) for 24 h, C. helgolandicus ingested 11% fewer algal cells (P = 0.33) and 40% less carbon biomass (P < 0.01). There was a net downward shift in the mean size of algal prey consumed (P < 0.001), with a 3.6 fold increase in ingestion rate for the smallest size class of algal prey (11.6–12.6 μm), suggestive of postcapture or postingestion rejection. Prolonged exposure to polystyrene microplastics significantly decreased reproductive output, but there were no significant differences in egg production rates, respiration or survival. We constructed a conceptual energetic (carbon) budget showing that microplastic-exposed copepods suffer energetic depletion over time. We conclude that microplastics impede feeding in copepods, which over time could lead to sustained reductions in ingested carbon biomass.

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2015 se recordará como el gran año del cambio en los medios de comunicación, especialmente para la prensa. A lo largo del mismo se ha llevado a cabo una enconada lucha entre los editores y Google News, a la que se han sumado Yahoo News, Facebook, LinkedIn, Twitter, etc., para determinar quién debe pagar por los contenidos, quién los creará, quién los distribuirá y quién y cómo los leerá. Nuevos pactos para nuevos lectores. Nuevos acuerdos para reflotar económicamente la prensa. Y todo ello bajo el paraguas de la Ley de Propiedad Intelectual en España y otras similares que se irán publicando o adaptando en Europa. Se ofrece un estudio y análisis de la situación previa al establecimiento de dicha ley y las consecuencias de su aplicación.

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La información es el elemento primordial en una Institución, sea del carácter que sea. Fluye de cualquier departamento que la integra y esta información hay que recopilarla, ordenarla, sintetizarla, tratarla y por último y más relevante hay que distribuirla. No se puede retener ni ocultar, se debe canalizar para que todos los integrantes de esa empresa la conozcan, la entiendan, la asuman y la hagan suya. Es así como funcionan bien los organismos conociendo lo que trabajan, sus objetivos, sus límites, sus avances y sus logros. Los gabinetes de comunicación son el motor de la documentación. Gestionan los contenidos, crean archivos de datos y documentos y difunden la información, no solo entre los diferentes componentes de la empresa sino también entre los distintos estamentos de la sociedad, proyectando al exterior la imagen de la Institución para la que trabajan.

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Aim: To study the relation between visual impairment and ability to care for oneself or a dependant in older people with age related macular degeneration (AMD). Method: Cross sectional study of older people with visual impairment due to AMD in a specialised retinal service clinic. 199 subjects who underwent visual function assessment (fully corrected distance and near acuity and contrast sensitivity in both eyes), followed by completion of a package of questionnaires dealing with general health status (SF36), visual functioning (Daily Living Tasks Dependent on Vision, DLTV) and ability to care for self or provide care to others. The outcome measure was self reported ability to care for self and others. Three levels of self reported ability to care were identified—inability to care for self (level 1), ability to care for self but not others (level 2), and ability to care for self and others (level 3). Results: People who reported good general health status and visual functioning (that is, had high scores on SF36 and DLTV) were more likely to state that they were able to care for self and others. Similarly people with good vision in the better seeing eye were more likely to report ability to care for self and others. People with a distance visual acuity (DVA) worse than 0.4 logMAR (Snellen 6/15) had less than 50% probability of assigning themselves to care level 3 and those with DVA worse than 1.0 logMAR (Snellen 6/60) had a probability of greater than 50% or for assigning themselves to care level 1. Regression analyses with level of care as the dependent variable and demographic factors, DLTV subscales, and SF36 dimensions as the explanatory variables confirmed that the DLTV subscale 1 was the most important variable in the transition from care level 3 to care level 2. The regression analyses also confirmed that the DLTV subscale 2 was the most important in the transition from care level 3 to care level 1. Conclusions: Ability to care for self and dependants has a strong relation with self reported visual functioning and quality of life and is adversely influenced by visual impairment. The acuity at which the balance of probability shifts in the direction of diminished ability to care for self or others is lower than the level set by social care agencies for provision of support. These findings have implications for those involved with visual rehabilitation and for studies of the cost effectiveness of interventions in AMD.