973 resultados para Modern Standard Arabic


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Rare earth elements (REE), while not essential for the physiologic functions of animals, are ingested and incorporated in ppb concentrations in bones and teeth. Nd isotope compositions of modern bones of animals from isotopically distinct habitats demonstrate that the (143)Nd/(144)Nd of the apatite can be used as a fingerprint for bedrock geology or ambient water mass. This potentially allows the provenance and migration of extant vertebrates to be traced, similar to the use of Sr isotopes. Although REE may be enriched by up to 5 orders of magnitude during diagenesis and recrystallization of bone apatite, in vivo (143)Nd/(144)Nd may be preserved in the inner cortex of fossil bones or enamel. However, tracking the provenance of ancient or extinct vertebrates is possible only for well-preserved archeological and paleontological skeletal remains with in vivo-like Nd contents at the ppb-level. Intra-bone and -tooth REE analysis can be used to screen for appropriate areas. Large intra-bone Nd concentration gradients of 10(1)-10(3) are often measured. Nd concentrations in the inner bone cortex increase over timescales of millions of years, while bone rims may be enriched over millenial timescales. Nevertheless, epsilon(Nd) values are often similar within one epsilon(Nd) unit within a single bone. Larger intra-bone differences in specimens may either reflect a partial preservation of in vivo values or changing epsilon(Nd) values of the diagenetic fluid during fossilization. However, most fossil specimens and the outer rims of bones will record taphonomic (143)Nd/(144)Nd incorporated post mortem during diagenesis. Unlike REE patterns, (143)Nd/(144)Nd are not biased by fractionation processes during REE-uptake into the apatite crystal lattice, hence the epsilon(Nd) value is an important tracer for taphonomy and reworking. Bones and teeth from autochthonous fossil assemblages have small variations of +/- 1 epsilon(Nd) unit only. In contrast, fossil bones and teeth from over 20 different marine and terrestrial fossil sites have a total range of epsilon(Nd) values from -13.0 to 4.9 (n = 80), often matching the composition of the embedding sediment. This implies that the surrounding sediment is the source of Nd in the fossil bones and that the specimens of this study seem not to have been reworked. Differences in epsilon(Nd) values between skeletal remains and embedding sediment may either indicate reworking of fossils and/or a REE-uptake from a diagenetic fluid with non-sediment derived epsilon(Nd) values. The latter often applies to fossil shark teeth, which may preserve paleo-seawater values. Complementary to epsilon(Nd) values, (87)Sr/(86)Sr can help to further constrain the fossil provenance and reworking. (C) 2011 Elsevier Ltd. All rights reserved.

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OBJECTIVE: To compare image quality of a standard-dose (SD) and a low-dose (LD) cervical spine CT protocol using filtered back-projection (FBP) and iterative reconstruction (IR). MATERIALS AND METHODS: Forty patients investigated by cervical spine CT were prospectively randomised into two groups: SD (120 kVp, 275 mAs) and LD (120 kVp, 150 mAs), both applying automatic tube current modulation. Data were reconstructed using both FBP and sinogram-affirmed IR. Image noise, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were measured. Two radiologists independently and blindly assessed the following anatomical structures at C3-C4 and C6-C7 levels, using a four-point scale: intervertebral disc, content of neural foramina and dural sac, ligaments, soft tissues and vertebrae. They subsequently rated overall image quality using a ten-point scale. RESULTS: For both protocols and at each disc level, IR significantly decreased image noise and increased SNR and CNR, compared with FBP. SNR and CNR were statistically equivalent in LD-IR and SD-FBP protocols. Regardless of the dose and disc level, the qualitative scores with IR compared with FBP, and with LD-IR compared with SD-FBP, were significantly higher or not statistically different for intervertebral discs, neural foramina and ligaments, while significantly lower or not statistically different for soft tissues and vertebrae. The overall image quality scores were significantly higher with IR compared with FBP, and with LD-IR compared with SD-FBP. CONCLUSION: LD-IR cervical spine CT provides better image quality for intervertebral discs, neural foramina and ligaments, and worse image quality for soft tissues and vertebrae, compared with SD-FBP, while reducing radiation dose by approximately 40 %.

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Glioblastomas are the most malignant gliomas with median survival times of only 15 months despite modern therapies. All standard treatments are palliative. Pathogenetic factors are diverse, hence, stratified treatment plans are warranted considering the molecular heterogeneity among these tumors. However, most patients are treated with "one fits all" standard therapies, many of them with minor response and major toxicities. The integration of clinical and molecular information, now becoming available using new tools such as gene arrays, proteomics, and molecular imaging, will take us to an era where more targeted and effective treatments may be implemented. A first step towards the design of such therapies is the identification of relevant molecular mechanisms driving the aggressive biological behavior of glioblastoma. The accumulation of diverse aberrations in regulatory processes enables tumor cells to bypass the effects of most classical therapies available. Molecular alterations underlying such mechanisms comprise aberrations on the genetic level, such as point mutations of distinct genes, or amplifications and deletions, while others result from epigenetic modifications such as aberrant methylation of CpG islands in the regulatory sequence of genes. Epigenetic silencing of the MGMT gene encoding a DNA repair enzyme was recently found to be of predictive value in a randomized clinical trial for newly diagnosed glioblastoma testing the addition of the alkylating agent temozolomide to standard radiotherapy. Determination of the methylation status of the MGMT promoter may become the first molecular diagnostic tool to identify patients most likely to respond that will allow individually tailored therapy in glioblastoma. To date, the test for the MGMT-methylation status is the only tool available that may direct the choice for alkylating agents in glioblastoma patients, but many others may hopefully become part of an arsenal to stratify patients to respective targeted therapies within the next years.

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When referenced, the 2012 edition of the Iowa Department of Transportation’s (Iowa DOT) Standard Specifications for Highway and Bridge Construction shall be used for contract work awarded by the Iowa DOT. They may also be incorporated by reference in other contract work on secondary, urban, local systems, or other contract work in which the Iowa DOT has an interest. As modified by the General Supplemental Specifications, these Standard Specifications represent the minimum requirements and may be modified by Supplemental Specifications, Developmental Specifications, and Special Provisions on specific contracts. These Standard Specifications have been written so the Contractor’s responsibilities are indicated by plain language using the Imperative Mood and Active Voice form. Sentences are of the form: Construct isolation joints at all points where driveways meet other walks, curbs, or fixtures in the surface. Ensure finished members are true to detailed dimensions and free from twists, bends, open joints, or other defects resulting from faulty fabrication or defective work. Personnel preparing the JMF shall be Iowa DOT certified in bituminous mix design. The Contracting Authority’s responsibilities are (with some exceptions) indicated by the use of the modal verb “will”. Sentences are of the form: The Engineer will obtain and test density samples for each lot according to Materials I.M. 204. Payment will be the contract unit price for Fabric Reinforcement per square yard (square meter). These standard specifications contain dual units of measure: the United States Standard measure (English units) and the International System of Units (SI or “metric” units). The English units are expressed first then followed by the metric units in parentheses. The measurements expressed in the two systems are not necessarily equal. In some cases the measurements in metric units is a “hard” conversion of the English measurement; i.e. the metric unit has been approximated with a rounded, rationalized metric measurement that is easy to work with and remember. The proposal form will identify whether the work was designed and shall be constructed in English or metric units.

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BACKGROUND: Despite the increasing use of Roux-en-Y gastric bypass (RYGBP) in the treatment of morbid obesity, data about postoperative nutritional deficiencies and their treatment remain scarce. OBJECTIVE: The aim of this study was to evaluate the efficacy of a standard multivitamin preparation in the prevention and treatment of nutritional deficiencies in obese patients after RYGBP. DESIGN: This was a retrospective study of 2 y of follow-up of obese patients after RYGBP surgery. Between the first and the sixth postoperative months, a standardized multivitamin preparation was prescribed for all patients. Specific requirements for additional substitutive treatments were systematically assessed by a biologic workup at 3, 6, 9, 12, 18, and 24 mo. RESULTS: A total of 137 morbidly obese patients (110 women and 27 men) were included. The mean (+/-SD) age at the time of surgery was 39.9 +/- 10.0 y, and the body mass index (in kg/m(2)) was 46.7 +/- 6.5. Three months after RYGBP, 34% of these patients required at least one specific supplement in addition to the multivitamin preparation. At 6 and 24 mo, this proportion increased to 59% and 98%, respectively. Two years after RYGBP, a mean amount of 2.9 +/- 1.4 specific supplements had been prescribed for each patient, including vitamin B-12, iron, calcium + vitamin D, and folic acid. At that time, the mean monthly cost of the substitutive treatment was $34.83. CONCLUSION: Nutritional deficiencies are very common after RYGBP and occur despite supplementation with the standard multivitamin preparation. Therefore, careful postoperative follow-up is indicated to detect and treat those deficiencies.

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Glioma has been considered resistant to chemotherapy and radiation. Recently, concomitant and adjuvant chemoradiotherapy with temozolomide has become the standard treatment for newly diagnosed glioblastoma. Conversely (neo-)adjuvant PCV (procarbazine, lomustine, vincristine) failed to improve survival in the more chemoresponsive tumor entities of anaplastic oligoastrocytoma and oligodendroglioma. Preclinical investigations suggest synergism or additivity of radiotherapy and temozolomide in glioma cell lines. Although the relative contribution of the concomitant and the adjuvant chemotherapy, respectively, cannot be assessed, the early introduction of chemotherapy and the simultaneous administration with radiotherapy appear to be key for the improvement of outcome. Epigenetic inactivation of the DNA repair enzyme methylguanine methyltransferase (MGMT) seems to be the strongest predictive marker for outcome in patients treated with alkylating agent chemotherapy. Patients whose tumors do not have MGMT promoter methylation are less likely to benefit from the addition of temozolomide chemotherapy and require alternative treatment strategies. The predictive value of MGMT gene promoter methylation is being validated in ongoing trials aiming at overcoming this resistance by a dose-dense continuous temozolomide administration or in combination with MGMT inhibitors. Understanding of molecular mechanisms allows for rational targeting of specific pathways of repair, signaling, and angiogenesis. The addition of tyrosine kinase inhibitors vatalanib (PTK787) and vandetinib (ZD6474), the integrin inhibitor cilengitide, the monoclonal antibodies bevacizumab and cetuximab, the mammalian target of rapamycin inhibitors temsirolimus and everolimus, and the protein kinase C inhibitor enzastaurin, among other agents, are in clinical investigation, building on the established chemoradiotherapy regimen for newly diagnosed glioblastoma.

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Aquest treball ofereix l’estudi sobre l’aportació que va fer el dramaturg anglès del segle XVIXVII William Shakespeare en la filosofia política. El principal objectiu del treball consisteixen analitzar la seva obra teatral “Macbeth” destacant els element rellevants per la teoria política del seu període, és a dir l’època Moderna. El desenvolupament de les noves concepcions del món i de l’ordre social d’aquell moment va marcar un abans i un després enel pensament polític. En l’estudi, els aspectes polítics tractats en “Macbeth” es comparen amb les idees de Hobbes i Maquiavel per demostrar que malgrat Shakespeare mai ha sigut considerat com a un filòsof polític, les seves visions de la societat eren innovadores i sovint semblants a les visions de pensadors més il·lustres de la teoria política.

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Purpose: To compare the additional informations obtainedwith axial and sagittal T2 weighted with fat saturation(T2FS) and T1 weighted with Gadolinium iv sequenceswith fat saturation (T1FSGd) to detect degenerativeinflammatory lumbar spine lesions.Materials and Methods: Our retrospective study included73 patients (365 lumbar levels) with lumbar spinedegenerative disease (25 males, 48 females, mean age56 years). MRI protocol was performed with T1 and T2weighted sagittal and T2 weighted axial sequences(standard protocol), axial and sagittal T2FS and T1FSGd.Images were independently analyzed by two musculoskeletalradiologists and a neurosurgeon. Two groups ofsequences were analyzed: standard + T2FS sequences(group 1), standard + T1FSGd sequences (group 2).Degenerative inflammatory lumbar spine lesions werenoted at each level in: anterior column (vertebralendplate), spinal canal (epidural and peri-radicular fat)and posterior column (facet joint with capsular recessand subchondral bone).Results: Degenerative inflammatory lesions were present in18% (66/365) of levels in group 1, and 48% (175/365) oflevels in group 2. In details, lesions were noted in group 1 and2 respectively:-in 44 and 66 levels for anterior column,-in22 and 131 levels for posterior column,-in 0 and 36 levelsfor spinal canal. All these differences were statisticallysignificant. Intra and Interobserver agreements were good.Conclusion: The T1FSGd sequence is more sensitive thanT2FS to show the degenerative inflammatory lumbar spinelesions, especially in spinal canal and posterior column.

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The booklet tells the history of the construction of the Iowa Highway 376 Bridge within the context of significant modernization and expansion of the highway system in Iowa in the 1950s. Curvy, narrow highways were widened and straightened and narrow iron truss bridges were replaced with more modern concrete and steel structures, changing the landscape of rural Iowa. Bridge engineer Herbert A Arthur, who designed the Iowa Highway 376 Bridge, was a prolific bridge engineer in the 1950s. This booklet serves to inform the public of this significant aspect of Iowa transportation history.

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Concrete durability may be considered as the ability to maintain serviceability over the design life without significant deterioration, and is generally a direct function of the mixture permeability. Therefore, reducing permeability will improve the potential durability of a given mixture and, in turn, improve the serviceability and longevity of the structure. Given the importance of this property, engineers often look for methods that can decrease permeability. One approach is to add chemical compounds known as integral waterproofing admixtures or permeability-reducing admixtures, which help fill and block capillary pores in the paste. Currently, there are no standard approaches to evaluate the effectiveness of permeability-reducing admixtures or to compare different products in the US. A review of manufacturers’ data sheets shows that a wide range of test methods have been used, and rarely are the same tests used on more than one product. This study investigated the fresh and hardened properties of mixtures containing commercially available hydrophilic and hydrophobic types of permeability-reducing admixtures. The aim was to develop a standard test protocol that would help owners, engineers, and specifiers compare different products and to evaluate their effects on concrete mixtures that may be exposed to hydrostatic or non-hydrostatic pressure. In this experimental program, 11 concrete mixtures were prepared with a fixed water-to-cement ratio and cement content. One plain mixture was prepared as a reference, 5 mixtures were prepared using the recommended dosage of the different permeability-reducing admixtures, and 5 mixtures were prepared using double the recommended dosage. Slump, air content, setting time, compressive and flexural strength, shrinkage, and durability indicating tests including electrical resistivity, rapid chloride penetration, air permeability, permeable voids, and sorptivity tests were conducted at various ages. The data are presented and recommendations for a testing protocol are provided.

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BACKGROUND: NovoTTF is a portable device delivering low-intensity, intermediate-frequency, electric fields using noninvasive, disposable scalp electrodes. These fields physically interfere with cell division. Preliminary studies in recurrent and newly diagnosed glioblastoma (GBM) have shown promising results. A phase III study in recurrent GBM has recently been concluded. METHODS: Adults (KPS ≥ 70%) with recurrent GBM (any recurrence) were randomized (stratified by surgery and center) to either NovoTTF administered continuously (20-24 hours/day, 7 days/week) or the best available chemotherapy (best physician choice [BPC]). Primary endpoint was overall survival (OS); 6-month progression-free survival (PFS6), 1-year survival, and QOL were secondary endpoints. RESULTS: Two hundred thirty-seven patients were randomized (28 centers in the United States and Europe) to either NovoTTF alone (120 patients) or BPC (117 patients). Patient characteristics were balanced, median age was 54 years (range, 23-80 years), median KPS was 80% (range, 50-100). One quarter had surgery for recurrence, and over half were at their second or more recurrence. A survival advantage for the device group was seen in patients treated according to protocol (median OS, 7.8 months vs. 6.1 months; n = 185; p = 0.01). Moreover, subgroup analysis in patients with better prognostic baseline characteristics (KPS ≥ 80%; age ≤ 60; 1st-3rd recurrence) demonstrated a robust survival benefit for NovoTTF patients compared to matched BPC patients (median OS, 8.8 months vs. 6.6 months; n = 110; p < 0.01). In this group, 1-year survival was 35% vs. 20% and PFS6 was 25.6% vs. 7.7%. Interestingly, in patients who failed bevacizumab prior to the trial, OS was also significantly extended by NovoTTF (4.4 months vs. 3.1 months; n = 23 vs. n = 21; p < 0.02). Quality of life was equivalent or superior in NovoTTF patients. CONCLUSIONS: NovoTTF, a noninvasive, novel cancer treatment modality shows significant therapeutic efficacy with improved quality of life. The impact of NovoTTF was more pronounced when patients with better baseline prognostic factors were treated. A large scale phase III clinical trial in newly diagnosed GBM is currently being conducted.

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Aquest projecte és fruit de la meva necessitat de buscar amb el meu instrument, la percussió, i més concretament amb la pandereta, recursos tècnics i interpretatius per abordar la interpretació de la música antiga. Com a punt de partida he analitzat iconografia i algunes fonts literàries per tal d’entendre i poder explicar que s’entén quan parlem de la percussió històrica. Posteriorment s’observen algunes pràctiques encara existents en les tradicions musicals italianes i àrabs i com aquestes poden ser el punt de partida per a configurar una maner pròpia i moderna d’ interpretar i anotar la música històrica.