Experimental study of improved sclerotherapy injection in rat model of vertebral arteriocervical spondylopathy / 中国骨伤

OBJECTIVE@#To improve the rat model of cervical spondylosis of vertebral artery type (CSA) induced by injecting sclerosing agent. To evaluate the efficacy of injecting sclerosing agent to induce CSA.@*METHODS@#Forty Health SPF SD rats(20 males and 20 females), were randomly divided into two groups:the model group (20) and the blank group (20). All the animals were followed up for 4 weeks for the observation of general situation, transcranial Doppler(TCD) detection of blood flow velocity, pulsatility index and resistive index of the vertebral artery, measurement of mental distress by open-field test.@*RESULTS@#One to two days after establish the animal model, rats in the model group appeared apathetic with decreased autonomic activities, trembling, squinting, increased eye excrement, etc., and no rats died during the experiment. The mean blood flow velocity of the model group was lower than that of the blank group (P<0.05), and the pulsatilit index and resistive index of the model group were higher than that of the blank group (P<0.05). The mental distress of the model group was significantly higher than that of the blank group.@*CONCLUSION@#The modified injection of sclerosing agent is a practical method to establish the rat model of CSA, with high success rate, high stability, low mortality and simple operation.

Avaliação de propriedades físico-químicas, tempo de endurecimento e drenagem de um cimento endodôntico adicionado ao MTA em diferentes proporções / Evaluation of physico-chemical properties, time of hardening and draining of an endodontic sealer added to mta in different proportions

Objetivo: o objetivo desta pesquisa foi avaliar o tempo e o fluxo de endurecimento do cimento AH-PLUS e MTA nas proporções de 10%, 20% e 30%, a fim de adicionar a capacidade de estimular a deposição de tecido duro. Material e Métodos: Para o teste de fluxo, 0,5 ml de cimento foram depositados em uma placa de vidro e outra placa foi adicionada com uma carga adicional, após 10 minutos a carga foi removida e o diâmetro do círculo formado pelo cimento foi medido com um Bússola digital. Para o tempo de endurecimento, foram utilizados moldes cilíndricos preenchidos com o cimento testado, mantidos dentro de um forno e os testes de agulha de Gillmore foram realizados no material em intervalos de 60 segundos até que as marcas não fossem visíveis na superfície do cimento testado. Resultados: Na vazão, os valores obtidos foram: 41,1 mm (10% MTA), 32,86 mm (20% MTA), 21,91 mm (30% MTA), 24,41 mm AHPlus® e 26,47 mm MTA Fillapex®. O tempo de endurecimento encontrado nesta pesquisa foi de 1631 'em proporção (10% MTA), 628,4 em proporção (20% MTA), 567' em proporção (30% MTA), 767 em AH Plus e Fillapex MTA não. presou dentro de 6 semanas. Conclusão: concluiu-se que a adição de 10%, 20% e 30% de MTA ao AH Plus não alterou as propriedades do fluxo e o tempo estabelecido

Objective: evaluate the hardening time and flow of AH-PLUS and MTA cement in the proportions of 10%, 20% and 30% in order to add the ability to stimulate the deposition of hard tissue. Material and Methods: For the flow test, 0.5 ml of cement was deposited on a glass plate and another plate was added with an additional charge, after 10 minutes the charge was removed and the diameter of the circle formed by the cement was measured with a digital compass. For the hardening time, cylindrical molds filled with the tested cement were used, kept inside a kiln and Gillmore needle tests were performed on the material at 60 second intervals until the marks were not visible on the surface of the tested cement. Results: In the flow rate, the values obtained were: 41.1mm (10% MTA), 32.86mm (20% MTA), 21.91mm (30% MTA), 24.41mm AHPlus® and 26.47mm MTA Fillapex®. The hardening time found in this survey was 1631 'in proportion (10% MTA), 628.4 in proportion (20% MTA), 567' in proportion (30% MTA), 767 in AH Plus and Fillapex MTA did not. took prey within 6 weeks. Conclusion: it was concluded that the addition of 10%, 20% and 30% of MTA to AH Plus did not change the flow properties and the established time

Biomineralization of a calcifying ureolytic bacterium Microbacterium sp. GM-1

Background: Biomineralization is a significant process performed by living organisms in which minerals are produced through the hardening of biological tissues. Herein, we focus on calcium carbonate precipitation, as part of biomineralization, to be used in applications for environmental protection, material technology, and other fields. A strain GM-1, Microbacterium sp. GM-1, isolated from active sludge, was investigated for its ability to produce urease and induce calcium carbonate precipitation in a metabolic process. Results: It was discovered that Microbacterium sp. GM-1 resisted high concentrations of urea up to 60 g/L. In order to optimize the calcification process of Microbacterium sp. GM-1, the concentrations of Ni2+ and urea, pH value, and culture time were analyzed through orthogonal tests. The favored calcite precipitation culture conditions were as follows: the concentration of Ni2+ and urea were 50 µM and 60 g/L, respectively, pH of 10, and culture time of 96 h. Using X-ray diffraction analysis, the calcium carbonate polymorphs produced by Microbacterium sp. GM-1 were proven to be mainly calcite. Conclusions: The results of this research provide evidence that Microbacterium sp. GM-1 can biologically induce calcification and suggest that strain GM-1 may play a potential role in the synthesis of new biominerals and in bioremediation or biorecovery.

Experimental study on the effects of X-ray beam hardening from contrast agent on CT values / 实用放射学杂志

Objective To investigate the effects of X-ray beam hardening from contrast agent on CT values on CTA images.Methods The 20 mL syringes were numbered 1 to 26.The syringe 1,4,7,23 and 20 were filled with 1 mL,0.8 mL,0.6 mL,0.4 mL and 0.2 mL of iodine contrast medium (300 mg I/mL),respectively,and then mixed each of them with 0.9％ NaC1 solution to get a total of 20 mL solution in each syringe.The rest of 26 syringes were filled with 20 mL of 0.9％ NaC1 solution,as the experimental group to simulate carotid artery CTA examination.Matched 26 numbered syringes were filled with 20 mL 0.9％ NaC1 solution respectively,as control group to simulate plain scan.CT scans were performed,CT values were measured,and then the difference of CT values of 0.9 ％ NaCl solution in two groups was analyzed statistically.Results The mean,maximum and minimum CT values of saline in the experimental group vs control group were (-0.139±10.322) HU vs (5.585±2.939) HU,14.6 HU vs 9.7 HU,-23.8 HU vs-2.4 HU,respectively,and the differences were significant (t=2.695,P＜0.05).The CT values of saline around the high concentrations of iodine solution showed a large fluctuation range.Conclusion The X ray beam hardening effects caused by high concentration of iodine contrast on carotid artery CTA phase,may cause significant fluctuations of CT values.

The effect of a multi-material artifact reduction algorithm in a wide-detector CT system to reduce the beam hardening artifacts in CT imaging / 中华放射学杂志

Objective To investigate the effect of the multi-material artifact reduction (MMAR) algorithm of wide-detector CT system in reducing the beam hardening artifacts in brain CT imaging. Methods Nine tubes with various iodine concentrations (0.1-16.0 mgI/ml) were placed in a uniform phantom filled with soft-tissue equivalent material. The phantom was scanned using different combinations of the tube voltage and current as follows:80 kV/530 mA, 100 kV/295 mA, 120 kV/190 mA and 140 kV/135 mA. The scanning was performed using the GE Discovery 750 and GE Revolution CT scanners, respectively. The CT values and standard deviations of the uniform areas between tubes were measured. The artifact index (AI) was calculated by using the standard deviation value outside the tubes as background noise. The artifact index values under different kV/mA combinations with different scanners were compared. CT brain images of 36 patients (n=18 on Discovery CT and n=18 on Revolution CT) were randomly selected. CT values of normal brain tissue and dark bands areas in the posterior fossa were measured for each case. The AI was calculated for these cases as for the phantom study. Paired t test was performed for phantom data analysis, and independent t test was performed for the clinical cases data analysis. Results The average AI values with Revolution CT(4.96±1.39, 4.80±1.57, 4.56±1.45, 4.76±1.57) were smaller than those of Discovery 750 (11.90 ± 6.61, 11.17 ± 5.61, 8.85 ± 4.59, 8.77 ± 3.85) under different tube voltage settings(t=3.714, 4.186, 3.745, 4.634,P<0.001). The higher the iodine concentration difference between tube pairs was, the higher the artifact index;As for clinical data, the difference in AI values between Revolution CT(2.31 ± 0.95) and Discovery 750(3.91 ± 1.32) was found statistically significant(t=4.066,P<0.001). Conclusion The multi-material artifact reduction algorithm implemented on the wide-detector Revolution CT scanner can significantly reduce beam hardening artifacts.

The effect of a multi-material artifact reduction algorithm in a wide-detector CT system to reduce the beam hardening artifacts in CT imaging / 中华放射学杂志

Objective To investigate the effect of the multi-material artifact reduction (MMAR) algorithm of wide-detector CT system in reducing the beam hardening artifacts in brain CT imaging. Methods Nine tubes with various iodine concentrations (0.1-16.0 mgI/ml) were placed in a uniform phantom filled with soft-tissue equivalent material. The phantom was scanned using different combinations of the tube voltage and current as follows:80 kV/530 mA, 100 kV/295 mA, 120 kV/190 mA and 140 kV/135 mA. The scanning was performed using the GE Discovery 750 and GE Revolution CT scanners, respectively. The CT values and standard deviations of the uniform areas between tubes were measured. The artifact index (AI) was calculated by using the standard deviation value outside the tubes as background noise. The artifact index values under different kV/mA combinations with different scanners were compared. CT brain images of 36 patients (n=18 on Discovery CT and n=18 on Revolution CT) were randomly selected. CT values of normal brain tissue and dark bands areas in the posterior fossa were measured for each case. The AI was calculated for these cases as for the phantom study. Paired t test was performed for phantom data analysis, and independent t test was performed for the clinical cases data analysis. Results The average AI values with Revolution CT(4.96±1.39, 4.80±1.57, 4.56±1.45, 4.76±1.57) were smaller than those of Discovery 750 (11.90 ± 6.61, 11.17 ± 5.61, 8.85 ± 4.59, 8.77 ± 3.85) under different tube voltage settings(t=3.714, 4.186, 3.745, 4.634,P<0.001). The higher the iodine concentration difference between tube pairs was, the higher the artifact index;As for clinical data, the difference in AI values between Revolution CT(2.31 ± 0.95) and Discovery 750(3.91 ± 1.32) was found statistically significant(t=4.066,P<0.001). Conclusion The multi-material artifact reduction algorithm implemented on the wide-detector Revolution CT scanner can significantly reduce beam hardening artifacts.

Cambios microestructurales en los granos de Phaseolus vulgaris endurecidos / Microstructural changes in hardened beans (Phaseolus vulgaris)

El endurecimiento de los granos de Phaseolus vulgaris almacenados a alta temperatura y alta humedad relativa es una de las principales limitantes para su consumo. El objetivo de esta investigación fue evaluar por microscopia de barrido electrónico los cambios estructurales ocurridos en los cotiledones y en la testa de los granos endurecidos. Los granos recién cosechados se almacenaron durante doce meses bajo dos condiciones: 5°C-34% HR y 37°C-75% HR. Esta última con el fin de propiciar el endurecimiento. Los granos almacenados crudos y cocidos se liofilizaron y se fracturaron. Las secciones de testa y cotiledones se observaron en un microscopio electrónico JSM-6390. Al cabo de doce meses se constató que los granos almacenados a 37°C-75% HR aumentaron su dureza en un 503%, mientras que los granos almacenados a 5°C-34% HR no incrementaron su dureza significativamente. A nivel microestructural, en los cotiledones de los granos crudos se notaron claras diferencias en el aspecto de la pared celular, en el tamaño del espacio intercelular y en la textura de la matriz proteica. Mientras que en la testa de los granos crudos se evidenciaron diferencias en la compactación de la empalizada y de la capa sub-epidérmica. En los granos cocidos se observó una total separación entre las células de los cotiledones de los granos blandos y una muy limitada separación en los granos duros. Se concluye que las diferencias observadas en los granos duros y blandos, demostraron una participación importante de ambas estructuras, cotiledones y testa, en el endurecimiento de los granos.

The hardening of Phaseolus vulgaris beans stored at high temperature and high relative humidity is one of the main constraints for consumption. The objective of this research was to evaluate by scanning electron microscopy, structural changes in cotyledons and testa of the hardened beans. The freshly harvested grains were stored for twelve months under two conditions: 5 ° C-34% RH and 37 ° C-75% RH, in order to promote hardening. The stored raw and cooked grains were lyophilized and fractured. The sections of testa and cotyledons were observed in an electron microscope JSM-6390. After twelve months, grains stored at 37 ° C-75% RH increased their hardness by 503%, whereas there were no significant changes in grains stored at 5 ° C-34% RH. At the microstructural level, the cotyledons of the raw grains show clear differences in appearance of the cell wall, into the intercellular space size and texture matrix protein. There were also differences in compaction of palisade and sub-epidermal layer in the testa of raw grains. After cooking, cotyledon cells of the soft grains were well separated while these of hard grains were seldom separated. In conclusion, the found differences in hard and soft grains showed a significant participation of both structures, cotyledons and testa, in the grains´ hardening.

Direct multiple shoots proliferation of black night shade (Solanum nigrum l.) from shoot tip explants induced by thidiazuron .

The present investigation was undertaken in Black Night Shade (Solanum nigrum L.) which is an important medicinal plant. Direct multiple shoots proliferation was achieved from shoot tip. The shoot tips were cultured on MS medium fortified with Thidiazuron (TDZ) (1.0-7.0 mg/L) for multiple shoot induction. Multiple shoots proliferation was best observed at 3.0 mg/L TDZ from the shoot tip explants within three weeks of culture. Shoot number per explant ranged between 2 and 10. Individual shoots were aseptically excised and sub cultured in the same media for shoot elongation. The elongated shoots were transferred to Indole Acetic Acid/Indole Butyric Acid (IAA/IBA) (0.5mg/L–2.0mg/L) for root induction. Rooting was observed within two weeks of culture. Rooted plantlets were successfully hardened under culture conditions and subsequently established in the field conditions. The recorded survival rate of the plants was 86%. Plants looked healthy with no visually detectable phenotypic variations.

Evaluation of coronary stent by gemstone spectral imaging or high-definition scan:a phantom study / 天津医药

Objective To compare the displayed inner diameter of coronary stent by high definition(HD)and gem?stone spectral imaging(GSI)using dynamic cardiac and coronary artery phantom. Methods Five different types of coro?nary stents(internal diameter, 3.10 mm±0.55 mm;strut thickness, 0.12 mm±0.04 mm)were placed into a pulsating cardiac phantom(ALPHA 1-VT PC, Fuyo Corporation, Japan). The stent phantom was scanned by 3 systems, gemstone spectral im?aging(GSI), spiral scan(S)and HD. All the spectral imaging data were analyzed using GSI viewer to reconstruct the VMS (monochromic spectral) images(60-140 keV). Image noise(N), signal-to-noise ratio(SNR), contrast-to-noise ratio(CNR) and inner diameter were compared between images acquired through these 3 systems. Results SNRs in images of S and HD were higher than that of GSI(P0.05). The visible diameter(%)measurements of HD(0.85 ± 0.06)was significant higher than that of the other 2 scan systems and most close to the width of those stent’s actual size.(GSI:0.40±0.16, 0.48±0.13, 0.50±0.14, 0.51±0.13, 0.45±0.05,0.52±0.13, 0.53±0.13, 0.53±0.13, 0.53±0.13, S:0.53±0.14, P<0.05). Conclusion There was no significant dif?ferences in image quality among the images acquired by these 3 systems when the heart rate was set to 60 beats per min. Comparing to GSI and S, HD can produce best represent images to the known inner diameter of coronary stent.

Efficacy of the emergency endoscopic sclerotherapy and tissue adhesives embolization of bleeding esophageal varices / 中国综合临床

Objective To investigate clinical value of the emergency endoscopic sclerotherapy and tissue adhesives embolization on patients with gastroesophageal varices bleeding. Methods A retrospective analysis of 52 cases of esophageal variceal bleeding in patients with clinical data was performed. Of which,22 patients were given conservative treatment alone and they were served as conservative treatment group. Another 30 patients were given the emergency endoscopic sclerotherapy and/ or tissue adhesive embolization besides the basis of conservative treatment,and they served as endoscopic treatment group. The data of hospitalization and mortality,rebleeding rates were recorded during hospitalized time and 1 year off hospitalization. Results The indices of hospitalized periods in endoscopic treatment group was( 16. 2 ± 1. 5)d,shorter than that in conservative treatment group((17. 6 ± 2. 1)d,P = 0. 53). The mortality and rebleeding rate in endoscopic treatment group in followed up periods were 3. 3% and 6. 6%,lower than those in conservative treatment group (9. 1%,13. 6%),and the comparison of relative risk RR of two groups of mortality and rebleeding rate were 2. 76 and 2. 06. Conclusion The therapy of emergency endoscopic sclerotherapy and tissue adhesives embolization of bleeding esophageal varices shows a good effect and it is worth recommending.

Transcatheter arterial embolization using hardening agent combined with oral propranolol for the treatment of giant hemangioma at maxillofacial region in infants / 介入放射学杂志

Objective To discuss the therapeutic effect of transcatheter arterial embolization using hardening agent combined with oral propranolol in treating giant hemangioma at maxillofacial region in infants. Methods During the period from October 2013 to December 2014 at Imaging Center of Anhui Provincial Children's Hospital, transcatheter arterial embolization using hardening agent combined with oral propranolol was employed in a total of 27 infants with giant hemangioma at maxillofacial region. The age of the infants ranged from 2 months to 22 months (mean 5.9 months) and the body weight was 4.5-10 kg with a mean of 6.32 kg. Angiography via femoral artery was performed, which was followed by super-selective catheterization of hemangioma-feeding artery, and then pingyangmycin lipiodol emulsion was injected into the hemangiomas with subsequent injection of PVA particles to obstruct the hemangioma-feeding artery. After the embolization treatment, the patient received oral propranolol for 3-6 months. Results All the infant patients were followed up for 3-6 months. Clinical examination and ultrasonography indicated that the hemangioma was cured in 20 infants (75%) and the therapeutic result was effective in 7 infants (25%). Skin necrosis at hemangiomas site was observed in 2 infants (7.5%), which was cured after symptomatic treatment. No serious complications such as pulmonary embolism, cerebral embolism occurred, and no recurrence was observed. Conclusion For the treatment of giant hemangioma at maxillofacial region in infants, transcatheter arterial embolization using hardening agent combined with oral propranolol is minimally invasive, quickly effective and highly safe;and this treatment leaves no scar formation in most cases. Therefore, this technique is worthy of clinical application.

Induction of a Hardening Phenomenon and Quantitative Changes of Ceramides in Stratum Corneum

BACKGROUND: Hardening phenomenon of human skin after repeated exposure to the irritants is well-known, but the precise mechanism remains elusive. OBJECTIVE: To modify the previous experimental model of hardening phenomenon by repeated applications of two different concentrations of sodium lauryl sulfate (SLS) solutions to Korean healthy volunteers and to investigate the quantitative changes of ceramides in stratum corneum before and after chronic repeated irritation. METHODS: Eight hundred microliters of distilled water containing 0.1% and 2% SLS was applied for 10 minutes on the forearm of 41 healthy volunteers for 3 weeks. After an intervening 3-week rest, 24-hour patch tests with 1% SLS were conducted on previously irritated sites. Transepidermal water loss (TEWL), erythema index and quantity of ceramide were measured in the stratum corneum before and after irritation. RESULTS: TEWL values on the sites preirritated with 2% SLS were lower than those with 0.1% SLS. Hardening phenomenon occurred in 24 volunteers at day 44. The changes in ceramide levels were not significantly higher in the hardened skin than in the non-hardened skin. CONCLUSION: Repetitive stimulation with a higher concentration of SLS can more easily trigger skin hardening.

The study of dual energy spectral CT on the image quality of hand tendons / 实用放射学杂志

Objective To evaluate the image quality of hand tendons by using spectral CT,compared with conventional CT ima-ges.Methods Forty patients scanned with spectral CT were enrolled.The 65keV of optimal contrast-to-noise ratio (Optimal CNR) for viewing hand tendons was selected.The image quality of monochromatic GSI images (65 keV)and conventional CT images were compared with two different methods including subjective method and objective method by two radiologists respectively.Results In subjective method,the image quality in GSI images was superior to conventional CT images (P <0.05).And in objective method, the beam-hardening artifacts in the phalanges of fingers space were reduced markedly with hand tendons displaying more clearly in GSI images (P <0.05 ).There was no significant difference between the two radiologists in both methods with good correlation (Kappa=0.75,Kappa=0.85).Conclusion Spectral CT with the optimal 65keV monochromatic images could reduce the artifacts and increase image quality significantly in hand tendons imaging.It might be a very useful supplementary imaging method in detec-ting tendon diseases in routine work.

Research on the parameter setting on multi-slice spiral CT scan infants with congenital heart disease / 中国医学装备

Objective: To discuss the methods and experience of 64-slice spiral CT which used in infant cases with congenital heart disease, to select the appropriate scan parameters for reducing artifact and the radiation dose. Methods: Thirty-five cases with congenital heart disease were arranged CT examination by using Philips Brilliance 64-slice spiral CT scanner with Blous Tracking techniques. Results: All the images of the heart chambers, pulmonary artery, pulmonary vein, the ascending aorta and the descending aorta contrast agent filling showed good and had clear display. The density of superior vena cava is moderate. The various vascular CT value is approximate, no hardening artifacts. The atrioventricular of Cardiac and vascular of contrast agent filled fully and had clear boundary, no significant artifacts and no effect on the impact reconstruction. Conclusion: Appropriate adjustment of scanning parameters can reduce hardening artifact and the impact of artifacts. Following the principle of as low as reasonably achievable (ALARA) can obtain diagnostic images and reduce radiation damage to the infant.

Clinical research of endoscopic inferior turbinate fracture relocation press in treatment of chronic hypertrophic rhinitis / 中国基层医药

Objective To explore the clinical efficacy of intranasal endoscopic turbinate fracture relocation press in treatment of chronic hypertrophic rhinitis.Methods According to digital table,66 patients with chronic hypertrophic rhinitis were randomly divided into two groups.33 cases in the observation group were treated with endoscopic sinus lateral fracture crush,33 patients in the control group received inferior turbinate submucosal injection of sclerosing treatment.The clinical effect was compared between the two groups.Results The total effective rate of the observation group was 93.9％,which was significantly higher than 72.7％ of the control group (x2 =6.23,P ＜0.05).The average nasal recovery time was (35 ± 12)d in the observation group,which was significantly shorter than (64 ± 21) d in the control group (t =1.74,P ＜ 0.05).The SCT test results had statistically significant differences between the two groups before treatment and 3 months after treatment (t =3.21,2.85,all P ＜0.05).After treatment,the difference was statistically significant between the two groups (t =2.13,P ＜ 0.05).Conclusion Endoscopic turbinate fracture relocation squeezing surgery in the treatment of chronic hypertrophic rhinitis was satisfied.

Micropropagation and Phenolic exudation protocol for Excoecaria agallocha-an important mangrove

Objective: To develop a standard micropropagation protocol for an important vulnerable mangrove Excoecaria agallocha. Methods: Collection of explants, surface sterilization, phenolic exudation and medium was standardized. Shoot induction, shoot multiplication and rooting were carried out in MMS medium supplemented with BAP, Kinetin, Zeatin, 2ip, NAA, IAA and IBA. Hardening was carried out after root well established. Results: The best phenolic exudation removal was resulted in 4 g/L activated charcoal. The maximum shoot induction response showed in MMS medium and better shoot induction was performed in the concentration of BAP (3.9 μmol) and NAA (1.34 μmol). Rooting induction was performed high range at 5.02 μmol of IAA. Well rooted micro-shoots were hardened and acclimatized. Conclusions: From the present investigation, it can be concluded that a standard micropropagation protocol was developed for an important vulnerable mangrove species.

Clinic research of video-assisted thoracoscopic solitary pulmonary nodule resection after CT-guided hardening agent localization / 中华胸心血管外科杂志

Objective The aim of this study is to evaluate the efficacy and safety of preoperative CT-guided hardening agent localization.Methods From December 2010 to January 2012,27 patients with 29 solitary pulmonary nodules who had undergone CT-guided hardening agent localization and video-assisted thoracoscopic surgery (VATS) were studied.Results All cases were underwent CT-guided hardening agent localization successfully,and no patient had serious complication that required any intervention.The diameter of nodules ranged from 3 to 21 mm as measured by CT[mean (11.27 ± 6.32) mm].The distance between the center of nodule and visceral pleural ranged from 4 to 38 mm[mean (14.45 ± 4.32) mm].Conversion from VATS to thoracotomies was not necessary during the diagnostic resection procedure nodules.29 solitary pulmonary nodules underwent thoracoscopic wedge resection,and no intra-or postoperative mortality or morbidity was recorded.Conclusion CT-guided hardening agent localization before video-assisted thoracoscopic solitary pulmonary nodule resection is a safe and effective procedure for accurate diagnosis and resection of indeterminate solitary pulmonary nodules.

Modelo de endurecimiento isotrópico con esquema de integración explícita para biomateriales y su aplicación a la expansión de stents / Isotropic hardening model with explicit integration scheme for biomaterial and its application to stents expansion

Se presenta un modelo de endurecimiento isotrópico para biomateriales metálicos, el cual emplea un esquema de integración explícita bajo una formulación incremental. Para la implementación computacional se programó un elemento finito de usuario UEL en lenguaje FORTRAN para su ejecución en el software ABAQUS. Con el fin de validar el modelo se resuelven dos ejemplos tipo benchmark y sus resultados son comparados con ANSYS y el UMAT de Dunne y Petrinic para ABAQUS. Finalmente, el modelo es usado para simular la extensión de un stent coronario fabricado en acero inoxidable 316L. Se concluye que el modelo posee un error numérico aceptable teniendo en cuenta que el elemento finito fue programado por completo y no posee ninguna de las optimizaciones de los códigos comerciales. En trabajos futuros el UEL será acoplado con modelos de mecánica de daño continuo para la predicción de la falla por fatiga, cuyo análisis es un estándar básico en la manufactura de stents

A isotropic hardening model is presented for metallic biomaterials, which uses a explicit integration scheme under increasing formula. To computer implementation a finite element from UEL user was programmed in FORTRAN language for its execution in the ABAQUS software. To model validation two examples type benchmark were solved and results are compared with ANSYS and the UMAT of Dunne and Petrinic for ABAQUS. Finally, model is used to simulate the extension of a coronary stent manufactures in 316L stainless steel. We conclude that the model has an acceptable numerical error taking into account that finite element was programmed as a whole and has not any of the optimizations of commercial codes. In future papers the UEL will be coupled with continuous damage mechanics model to predict the failure due to fatigue, whose analysis is a basic standard in stent manufacturing

Interpretation of the stiffness and permeability of Sand-Kaolin mixtures in the framework of homogenization

This study deals with the behaviour of mixtures of sand and saturated kaolin paste considered as composite materials made of permeable and deformable (with non-linear behaviour) matrix (the kaolin paste) with rigid and impervious inclusions (the sand grains). Oedometric and permeability tests conducted on such mixtures highlight the key role of the state of the clay paste, and show the existence of a threshold of sand grain concentration above which a structuring effect influences both modulus and permeability. At the light of these experiments, the usual and tangent homogenization process (with simplifying assumptions to make the problem manageable) has been applied to estimate the mixture permeability and tangent compressibility. Qualitative and quantitative comparisons with experimental data point out the domain of interest and the limitations of such approaches.

O estudo lida com o comportamento de misturas compostas por areia e uma pasta de caulinita considerada um material composto feito de uma matriz (caulinita) permeável e deformável (com comportamento não-linear) com inclusões rígidas e impermeáveis (grãos de areia). Testes de permeabilidade e odométricos conduzidos nestas misturas enfatizam o papel chave de estado da pasta argilosa e mostram a existência de uma concentração crítica de grãos de areia com efeito estruturante que influencia o módulo e a permeabilidade. Sob a luz destes experimentos o processo de homogeneização usual e tangente (com hipóteses simplificadoras para tornar o problema tratável) foi aplicado para estimar a permeabilidade da mistura e a compressibilidade tangente. Comparações qualitativas e quantitativas com dados experimentais apontam o domínio de interesse bem como a limitação destas abordagens.

Genotypic variation in morphology and freezing resistance of Eucalyptus globulus seedlings subjected to drought hardening in nursery / Variación genotípica en la morfología y resistencia a la congelación del Eucalyptus globulus a la sequía sometido al endurecimiento en vivero

Eucalyptus globulus Labill is one of the most planted species in Chile, because of its fast growth and superior pulp qualities. Nevertheless, the incidence of drought and frost damage immediately after planting is frequent. The purpose of this work was to study the effect of drought hardening on frost resistance and on variations in morphological traits that may increase drought resistance at nursery phase in four genotypes of E. globulus Labill. Drought hardening treatments consisted in induced water stress by watering restriction, until pre-dawn stem xylem water potentials (Psi pd) reached -0.2, -1.8 and -2.6 MPa. Two water stress-rewatering cycles were applied during 54 days of hardening. Plant and root biomasses were affected by the interaction of drought hardening and genotypes. The rest of morphological and alometrical traits were affected independently by drought or genotype. Plant height, leaf area, specific leaf area (SLA), stem, and leaf biomasses decreased with drought hardening, while collar diameter was not affected. Genotypes responded differentially to drought hardening in plant height, leaf area, SLA, and stem, and leaf biomasses. Ice nucleation temperature (INT), and freezing temperatures (FRT), and 50 percent freezing damage index of leaves (LT50) were affected by the interaction between drought hardening and genotypes. EG-13, EG-23 and EG-22 genotypes became freezing tolerant with drought hardening (-2.6 MPa). Additionally, EG-14 genotype increased its freezing resistance at -1.8 MPa. Therefore, freezing resistance levels and mechanism depend on genotype and drought hardening treatment. The success in tree breeding by genetic selection should be facilitated by improved understanding of the physiology of stress resistance development and survival during water supply limitations. The knowledge of morphological and freezing resistance dependency on the interaction between genotype and drought hardening may be useful...