Elastic behavior of vanadinite, Pb10(VO4)6Cl2, a microporous non-zeolitic mineral

Gatta, G. Diego,Lee, Yongjae,Kao, Chi-Chang Springer-Verlag 2009 Physics and chemistry of minerals Vol.36 No.6

Zeolites at high pressure: A review

Gatta, G.D.,Lee, Y. MINERALOGICAL SOCIETY 2014 Mineralogical magazine Vol.78 No.2

Stability of (Cs, K)Al4Be5B11O28 (londonite) at high pressure and high temperature: a potential neutron absorber material

Gatta, G. Diego,Vignola, Pietro,Lee, Yongjae Springer-Verlag 2011 Physics and chemistry of minerals Vol.38 No.6

High-pressure behavior and crystal-fluid interaction under extreme conditions in paulingite [PAU-topology]

Gatta, G.D.,Scheidl, K.S.,Pippinger, T.,Skala, R.,Lee, Y.,Miletich, R. Elsevier 2015 Microporous and mesoporous materials Vol.206 No.-

The compressional behavior and the P-induced crystal-fluid interaction of a natural paulingite-K have been explored on the basis of in-situ single-crystal and powder X-ray diffraction, and in-situ single-crystal Raman spectroscopy with a diamond anvil cell and a series of diverse pressure-transmitting fluids (i.e., silicone-oil, methanol:ethanol=4:1, methanol:ethanol:water=16:3:1). No evidence of any phase transition was observed within the P-range investigated, independent on the used P-fluids. The compressional behavior of paulingite is significantly different in response to the different nature of the P-fluids. A drastically lower compressibility is observed when the zeolite is compressed in methanol:ethanol or, even more noticeably, in methanol:ethanol:water mix. We ascribe this phenomenon to the different crystal-fluid interaction at high pressure: (1) silicone-oil is a ''non-penetrating'' P-medium, because of its polymeric nature, whereas (2) methanol-ethanol and water are ''penetrating'' P-fluids. The P-induced penetration processes appear to be completely reversible on the basis of the X-ray diffraction data alone. The Raman spectra collected after the high-pressure experiments show, unambiguously, that a residual fraction of methanol (and/or ethanol and probably even extra H<SUB>2</SUB>O) still resides in the zeolitic sub-nanocavities; such molecules are spontaneously released after a few days at atmospheric pressure. The actual compressibility of paulingite-K is that obtained by the compression experiment in silicone-oil, with an isothermal bulk modulus K<SUB>0</SUB>=β<SUB>0</SUB><SUP>-1</SUP>=18.0(1.1)GPa. Paulingite appears to be one of the softest zeolite ever found.

Magnetic Resonance Myocardial Feature Tracking in Transfusion-Dependent Myelodysplastic Syndrome

Marta Alonso-Fernandez-Gatta,Ana Martin-Garcia,Maria Diez-Campelo,Agustin C. Martin-Garcia,Manuel Barreiro-Pérez,Félix Lopez-Cadenas,Elena Diaz-Pelaez,Pedro L. Sanchez 한국심초음파학회 2021 Journal of Cardiovascular Imaging (J Cardiovasc Im Vol.29 No.4

BACKGROUND: Myocardial deformation with echocardiography allows early detection of systolic dysfunction and is related to myocardial iron overload (MIO) determined by T2* in hereditary anemias under transfusion support. Our aim was to analyze the diagnostic and prognostic usefulness of magnetic resonance feature tracking (MR-FT) myocardial strain in low-risk myelodysplastic syndromes (LR-MDS) patients. METHODS: Prospective study in transfusion-dependent LR-MDS patients and healthy controls who underwent a cardiac MR-FT. We analyzed the relationships between strain MR-FT and iron overload parameters and its prognostic impact in cardiovascular events and/or death. RESULTS: Thirty-one patients and thirteen controls were included. MIO (T2* < 20 ms) was detected in 9.7% of patients. Left ventricular global longitudinal strain (LV-GLS) by MR-FT was pathological (> −19.3%) in 32.3% of patients. Less negative strain values correlated with lower T2* (R = −0.37, p = 0.033) and native myocardial T1 (R = −0.39, p = 0.031) times. LV-GLS by MR-FT was significantly associated with higher incidence of the combined cardiovascular events and/or all-cause death (p = 0.047), with a cut-off value of −17.7% for predicting them (63% sensitivity and 81% specificity, area under the curve = 0.69). After adjusting analysis including demographic, biomarkers and imaging variables, a higher LV-GLS value by MR-FT remained as predictor of combined event in transfusion-dependent LR-MDS patients (hazard ratio, 0.4; confidence interval, 0.15–0.98; p = 0.045). CONCLUSIONS: Longitudinal myocardial strain by MR-FT in LR-MDS patients is associated to MIO and correlates with adverse events in the follow-up, what could serve as a prognostic tool.

Topotactic and reconstructive changes at high pressures and temperatures from Cs-natrolite to Cs-hexacelsian

Hwang, Huijeong,Seoung, Donghoon,Gatta, G. Diego,Blom, Douglas A.,Vogt, Thomas,Lee, Yongjae Mineralogical Society of America 2015 The American mineralogist Vol.100 No.7

<P>Synchrotron X-ray powder diffraction experiments have been performed on dehydrated Cs- exchanged natrolite to systematically investigate successive transitions under high pressures and temperatures. At pressures above 0.5(1) GPa using H<SUB>2</SUB>O as a pressure-transmitting medium and after heating to 100 °C, dehydrated Cs<SUB>16</SUB>Al<SUB>16</SUB>Si<SUB>24</SUB>O<SUB>80</SUB> (deh-Cs-NAT) transforms to a hydrated phase Cs<SUB>16</SUB>Al<SUB>16</SUB>Si<SUB>24</SUB>O<SUB>80</SUB>·16H<SUB>2</SUB>O (Cs-NAT-II), which has a ca. 13.9% larger unit-cell volume. Further compression and heating to 1.5 GPa and 145 °C results in the transformation of Cs-NAT-II to Cs<SUB>16</SUB>Al<SUB>16</SUB>Si<SUB>32</SUB>O<SUB>96</SUB> (anh-Cs-POL), a H<SUB>2</SUB>O-free pollucite-like triclinic phase with a 15.6% smaller unit-cell volume per 80 framework oxygen atoms (80O<I><SUB>f</SUB></I>). At pressures and temperatures of 3.7 GPa and 180 °C, a new phase Cs<SUB>1.547</SUB>Al<SUB>1.548</SUB>Si<SUB>6.452</SUB>O<SUB>16</SUB> (Cs-HEX) with a hexacelsian framework forms, which has a ca. 1.8% smaller unit-cell volume per 80O<I><SUB>f</SUB></I><I>.</I> This phase can be recovered after pressure release. The structure of the recovered Cs-HEX has been refined in space group <I>P</I>6<SUB>3</SUB>/<I>mcm</I> with <I>a</I> = 5.3731(2) Å and <I>c</I> = 16.6834(8) Å, and also been confirmed by HAADF-STEM real space imaging. Similar to the hexacelsian feldspar (i.e., BaAl<SUB>2</SUB>Si<SUB>2</SUB>O<SUB>8</SUB>), Cs-HEX contains Cs<SUP>+</SUP> cations that act as bridges between the upper and lower layers composed of tetrahedra and are hexa-coordinated to the upper and lower 6-membered ring windows. These pressure- and temperature-induced reactions from a zeolite to a feldspar-like material are important constraints for the design of materials for Cs<SUP>+</SUP> immobilization in nuclear waste disposal.</P>

Comparative compressional behavior of chabazite with Li⁺, Na⁺, Ag⁺, K⁺, Rb⁺, and Cs⁺ as extra-framework cations

Kong, Mihye,Lee, Yongmoon,Diego Gatta, G.,Lee, Yongjae Mineralogical Society of America 2018 The American mineralogist Vol.103 No.2

<P><B>Abstract</B></P><P>The high-pressure behavior of monovalent-cation-exchanged chabazites was investigated by means of in situ synchrotron X-ray powder diffraction with a diamond-anvil cell, and using water as penetrating pressure-transmitting medium, up to 5.5 GPa at room temperature. In all cases, except for Na-containing chabazites, a phase transition from the original rhombohedral (<I>R</I>3m) to triclinic symmetry (likely<I>P</I>1) was observed in the range between 3.0 GPa and 5.0 GPa. The phase transition is accompanied by an abrupt decrease of the unit-cell volume by up to 10%. Evidence of pressure-induced hydration (PIH), i.e.,<I>P</I>-induced penetration of H<SUB>2</SUB>O molecules through the zeolitic cavities, was observed, as reflected by the incompressibility of the cation-exchanged chabazites, which is governed by the distribution of the extra-framework cations. The reversibility of the PIH and<I>P</I>-induced phase transitions in the high-pressure behavior of the cation-exchanged chabazites are discussed in the context of the role played by the chemical nature and bonding configuration of the extra-framework cations, along with that of the H<SUB>2</SUB>O content at room conditions.</P>

Prevalence and Comparison of Diagnostic Methods for Trichomonas vaginalis Infection in Pregnant Women in Argentina

Beatriz E. Perazzi,Claudia I. Menghi,Enrique F. Coppolillo,Claudia Gatta,Martha Cora Eliseth,Ramon A. de Torres,Carlos A. Vay,Angela M. R. Famiglietti 대한기생충학열대의학회 2010 The Korean Journal of Parasitology Vol.48 No.1

The objectives of this study were to conduct a prevalence survey of trichomoniasis in pregnant women and to evaluate the utility of different methods for its diagnosis. A total of 597 vaginal exudates from pregnant women who were examined at the Hospital de Clinicas in Buenos Aires, Argentina from 1 August 2005 to 31 January 2007, were prospectively and consecutively evaluated. The investigation of Trichomonas vaginalis was made by different microscopic examinations, and culture on liquid medium. The sensitivity and specificity of the microscopic examinations were assessed considering culture on liquid medium as the “gold standard”. The prevalence of T. vaginalis obtained by culture on liquid medium was 4.0% (24/597). The prevalence of T. vaginalis obtained by direct wet smear, prolonged May-Grunwald Giemsa staining, and sodium acetate-formalin (SAF)/methylene blue staining-fixing technique was 1.8%, 2.3% and 2.5%, respectively. The sensitivity of the direct wet smear was 45.8%, that of the prolonged May-Grunwald Giemsa staining was 58.3%, and that of the SAF/methylene blue method was 62.5%. Considering the 3 microscopic examinations altogether, the sensitivity rose to 66.7% and the specificity was 100% for all of them. This is the first time that the prevalence data of T. vaginalis by culture in pregnant women are published in Argentina. Due to the low sensitivity obtained by microscopy in asymptomatic pregnant women, the use of the liquid medium is recommended during pregnancy, in order to provide an early diagnosis and treatment.

Getting Down to the Bare Bones: Does laminoplasty or laminectomy With Fusion Provide Better Outcomes for Patients With Multilevel Cervical Spondylotic Myelopathy?

Nolan J. Brown,Brian V. Lien,Shane Shahrestani,Elliot H. Choi,Katelynn Tran,Sandra Gattas,Seth C. Ransom,Ali R. Tafreshi,Ryan Chase Ransom,Ronald Sahyouni,Alvin Chan,Michael Oh 대한척추신경외과학회 2021 Neurospine Vol.18 No.1

Objective: Cervical spondylotic myelopathy (CSM) is a degenerative disorder leading to progressive decline in spinal cord function. Cervical laminoplasty (CLP) and cervical laminectomy with fusion (CLF) are standard treatments for multilevel CSM. However, it is still unclear whether one procedure over the other provides better outcomes. Here, we performed a comprehensive review of published articles that compare the clinical outcomes and costs between CLP and CLF for CSM. Methods: A literature search was performed using PubMed, Web of Science, and Cochrane databases. Strict exclusion criteria were applied, and included articles were then assessed for publication year, study design, and significant differences in outcome variables. Results: From 519 studies identified with search terms, 38 studies were included for the qualitative analysis. Statistically significant differences in the clinical outcomes and costs were found in 18 studies. Eleven studies were prospective or retrospective, and 8 studies were meta-analyses. For the outcome variables of interest, results were reported by classifying into prospective studies, retrospective studies, and meta-analyses. Conclusion: CLP and CLF are 2 of the most commonly performed surgical procedures for the treatment of CSM. Although CLP and CLF each provide satisfactory clinical outcomes for patients with CMS, CLP may result in better cervical range of motion and less cost, length of stay, operation time, blood loss, paraspinal muscular atrophy, and rate of nerve palsies as compared to CLF. The major limitation of CLP versus CLF comparison studies includes the heterogeneity in techniques and preoperative criteria. Thus, further validation and investigations in larger cohorts will be required.

Optimization of Trichomonas vaginalis Diagnosis during Pregnancy at a University Hospital, Argentina

Pamela Testardini,Maria Lucia Gallo Vaulet,Andrea Carolina Entrocassi,Claudia Menghi,Martha Cora Eliseht,Claudia Gatta,Mirta Losada,Maria Sol Touzon,Ana Corominas,Carlos Vay,Silvio Tatti,Angela Famigl 대한기생충학열대의학회 2016 The Korean Journal of Parasitology Vol.54 No.2

The aim of this study was to evaluate different methods for Trichomonas vaginalis diagnosis during pregnancy in order to prevent maternal and perinatal complications. A total of 386 vaginal exudates from pregnant women were analyzed. T. vaginalis was investigated by 3 types of microscopic examinations direct wet mount with physiologic saline solution, prolonged May-Grunwald Giemsa (MGG) staining, and wet mount with sodium-acetate-formalin (SAF)/methylene blue method. PCR for 18S rRNA gene as well as culture in liquid medium were performed. The sensitivity and specificity of the microscopic examinations were evaluated considering the culture media positivity or the PCR techniques as gold standard. The frequency of T. vaginalis infection was 6.2% by culture and/or PCR, 5.2% by PCR, 4.7% by culture, 3.1% by SAF/methylene blue method and 2.8% by direct wet smear and prolonged MGG staining. The sensitivities were 83.3%, 75.0%, 50.0%, and 45.8% for PCR, culture, SAF/methylene blue method, and direct wet smear-prolonged MGG staining, respectively. The specificity was 100% for all the assessed methods. Microscopic examinations showed low sensitivity, mainly in asymptomatic pregnant patients. It is necessary to improve the detection of T. vaginalis using combined methods providing higher sensitivity, such as culture and PCR, mainly in asymptomatic pregnant patients, in order to prevent maternal and perinatal complications.