Study Some of Optical and Thermoluminescence Properties of Muscovite Mica Exposed to Ultraviolet Radiation

Thermoluminescence properties of ultraviolet-irradiated muscovite sample from Egypt have been studied. One TL peak is observed in the natural material around 190 14鈩?/m:t>"> . A linear response curve to ultraviolet radiation was obtained over the exposure time ranging from 15min to 75 min. A fading study over a period of 15 days shows that the UV-exposed aliquots faded by 27% when exposed for 150 min. The optical direct band gap decreased closely from 3.2eV to 3.1eV after irradiation which means improving crystallinity. Urbach energy decreased from 1.9eV to 1.8eV after irradiation shows less structural disorder. These results further indicate the potential of muscovite as a phosphor in retrospective dosimetry and TL dating. Keywords: Muscovite, optical properties, thermoluminescence properties,ultraviolet-irradiation

A Risk Assessment Model on Pine Wood Nematode in the EU

Pine wood nematode, B. xylophilus poses a serious threat for the European forest industry. This study applies a quantitative risk assessment to analyze the risk of pine wood nematode in the EU, by estimating the reduction expected within forestry stock available for wood supply and its downstream roundwood market. Spatial analysis is used to join information on climate suitability, host distribution, pest spread and value of assets. Economic impacts are presented spatially on a NUTS-2 scale based on partial budgeting technique and for the EU as a whole based on partial equilibrium modeling. Results highlight the Southern regions of Europe as high risk areas with a total impact on available forestry stock of 19,000 M € after 20 years of an outbreak and no regulatory control measures. Welfare analysis of the roundwood market, in which its production represents 2,5% of forestry stock, demonstrates the ability of the producers to pass most of the negative impact to the consumers by charging higher prices. Reduction in social welfare estimated at 2,043 M €, where consumer surplus decreased by 2,622 M € and net producer surplus, affected and non-affected producers, increased by 579 M €.Risk assessment, pine wood nematode, economic analysis, EU, Crop Production/Industries, Risk and Uncertainty,

Phototransferred Thermoluminescence from Obsidian Using Ultraviolet Radiation

The behavior of TL and PTTL under UV stimulation in gamma-irradiated obsidian was investigated. The noticeable change of the shape of the main TL peak after thermal or optical stimulation clearly shows that this peak is related to at least two traps. The PTTL curves recorded after preheating up to a given increased end temperatures are described by two processes. The first one is associated to the decay of the traps responsible for the main TL peak. The second is related with the phototransfer from the deep to the main trap. Fading studies over a period of 14 days show that the PTTL faded by 5% when exposed to 50Gy.The results further predict the potential of obsidian as a phosphor in TL dating, accident and industrial dosimetry. Keywords: Obsidian, Phototransfer, Phosphor, Fading

Diffusion Tensor Imaging in a Large Longitudinal Series of Patients With Cervical Spondylotic Myelopathy Correlated With Long-Term Functional Outcome

BACKGROUND Fractional anisotropy (FA) of the high cervical cord correlates with upper limb function in acute cervical cord injury. We investigated the correlation between preoperative FA at the level of maximal compression and functional recovery in a group of patients after decompressive surgery for cervical spondylotic myelopathy (CSM). OBJECTIVE To determine the usefulness of FA as a biomarker for severity of CSM and as a prognostic biomarker for improvement after surgery. METHODS Patients received diffusion tensor imaging (DTI) scans preoperatively. FA values of the whole cord cross-section at the level of maximal compression and upper cervical cord (C1-2) were calculated. Functional status was measured using the modified Japanese Orthopedic Association (mJOA) scale preoperatively and at follow-up up to 2 yr. Regression analysis between FA and mJOA was performed. DTI at C4-7 was obtained in controls. RESULTS Forty-four CSM patients enrolled prior to decompression were compared with 24 controls. FA at the level of maximal compression correlated positively with preoperative mJOA score. Preoperative FA correlated inversely with recovery throughout the postoperative period. This was statistically significant at 12 mo postoperation and nearly so at 6 and 24 mo. Patients with preoperative FA0.55. CONCLUSION In the largest longitudinal study of this kind, FA promises a valid biomarker for severity of CSM and postoperative improvement. FA is an objective measure of function and could provide a basis for prognosis. FA is particularly useful if preoperative values are less than 0.55

Presurgical tear characteristics and estimated shear modulus as predictors of repair integrity and shoulder function one year after rotator cuff repair

Background: Rotator cuff repair provides pain relief for many patients; however, retears are relatively common and affect approximately 20%-70% of patients after repair. Although magnetic resonance imaging (MRI) offers the ability to assess tissue characteristics such as tear size, retraction, and fatty infiltration, it provides little insight into the quality of the musculotendinous tissues the surgeon will encounter during surgery. However, shear wave elastography (SWE) could provide an indirect assessment of quality (ie, stiffness) by measuring the speed of shear waves propagating through tissue. The objective of this study was to determine the extent to which estimated shear modulus predicts repair integrity and functional outcomes 1 year after rotator cuff repair. Methods: Thirty-three individuals scheduled to undergo arthroscopic rotator cuff repair were enrolled in this study. Before surgery, shear modulus of the supraspinatus tendon and muscle was estimated using ultrasound SWE. MRIs were obtained before and 1 year after surgery to assess tear characteristics and repair integrity, respectively. Shoulder strength, range of motion, and patient-reported pain and function were assessed before and after surgery. Functional outcomes were compared between groups and across time using a two-factor mixed model analysis of variance. Stepwise regression with model comparison was used to investigate the extent to which MRI and shear modulus predicted repair integrity and function at 1 year after surgery. Results: At 1 year after surgery, 56.5% of patients had an intact repair. No significant differences were found in any demographic variable, presurgical tear characteristic, or shear modulus between patients with an intact repair and those with a recurrent tear. Compared with presurgical measures, patients in both groups demonstrated significant improvements at 1 year after surgery in pain (P \u3c .01), self-reported function (P \u3c .01), range of motion (P \u3c .01), and shoulder strength (P \u3c .01). In addition, neither presurgical MRI variables (P \u3e .16) nor shear modulus (P \u3e .52) was significantly different between groups at 1 year after surgery. Finally, presurgical shear modulus generally did not improve the prediction of functional outcomes above and beyond that provided by MRI variables alone (P \u3e .22). Conclusion: Although SWE remains a promising modality for many clinical applications, this study found that SWE-estimated shear modulus did not predict repair integrity or functional outcomes at 1 year after surgery, nor did it add to the prediction of outcomes above and beyond that provided by traditional presurgical MRI measures of tear characteristics. Therefore, it appears that further research is needed to fully understand the clinical utility of SWE for musculoskeletal tissue and its potential use for predicting outcomes after surgical rotator cuff repair

Efeito de Eucalyptus spp. e da superfície foliar na excreção de honeydew e sobrevivência de adultos do percevejo bronzeado.

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Aspectos biológicos de Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) em Eucalyptus benthamii em diferentes temperaturas.

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