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1.
Int J Cancer ; 154(10): 1857-1868, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38212892

RESUMO

Distinguishing primary liver cancer (PLC), namely hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA), from liver metastases is of crucial clinical importance. Histopathology remains the gold standard, but differential diagnosis may be challenging. While absent in most epithelial, the expression of the adherens junction glycoprotein N-cadherin is commonly restricted to neural and mesenchymal cells, or carcinoma cells that undergo the phenomenon of epithelial-to-mesenchymal transition (EMT). However, we recently established N- and E-cadherin expression as hallmarks of normal hepatocytes and cholangiocytes, which are also preserved in HCC and iCCA. Therefore, we hypothesized that E- and/or N-cadherin may distinguish between carcinoma derived from the liver vs carcinoma of other origins. We comprehensively evaluated E- and N-cadherin in 3359 different tumors in a multicenter study using immunohistochemistry and compared our results with previously published 882 cases of PLC, including 570 HCC and 312 iCCA. Most carcinomas showed strong positivity for E-cadherin. Strong N-cadherin positivity was present in HCC and iCCA. However, except for clear cell renal cell carcinoma (23.6% of cases) and thyroid cancer (29.2%), N-cadherin was only in some instances faintly expressed in adenocarcinomas of the gastrointestinal tract (0%-0.5%), lung (7.1%), pancreas (3.9%), gynecological organs (0%-7.4%), breast (2.2%) as well as in urothelial (9.4%) and squamous cell carcinoma (0%-5.6%). As expected, N-cadherin was detected in neuroendocrine tumors (25%-75%), malignant melanoma (46.2%) and malignant mesothelioma (41%). In conclusion, N-cadherin is a useful marker for the distinction of PLC vs liver metastases of extrahepatic carcinomas (P < .01).


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Colangiocarcinoma/patologia , Caderinas/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/patologia
2.
Inorg Chem ; 63(20): 9129-9144, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38709976

RESUMO

In the development of sodium all-solid-state batteries (ASSBs), research efforts have focused on synthesizing highly conducting and electrochemically stable solid-state electrolytes. Glassy solid electrolytes (GSEs) have been considered very promising due to their tunable chemistry and resistance to dendrite growth. For these reasons, we focus here on the atomic-level structures and properties of GSEs in the compositional series (0.6-0.08y)Na2S + (0.4 + 0.08y)[(1 - y)[(1 - x)SiS2 + xPS5/2] + yNaPO3] (NaPSiSO). The mechanical moduli, glass transition temperatures, and temperature-dependent conductivity were determined and related to their short-range order structures that were determined using Raman, Fourier transform infrared, and 31P and 29Si magic angle spinning nuclear magnetic resonance spectroscopies. In addition, the conductivity activation energies were modeled using the Christensen-Martin-Anderson-Stuart model. These GSEs appear to be highly crystallization-resistant in the supercooled liquid region where no measurable crystallization below 450 °C could be observed in differential scanning calorimetry studies. Additionally, these GSEs were found to be highly conducting, with conductivities on the order of 10-5 (Ω cm)-1 at room temperature, and processable in the supercooled state without crystallization. For all these reasons, these NaPSiSO GSEs are considered to be highly competitive and easily processable candidate GSEs for enabling sodium ASSBs.

3.
J Phys Chem A ; 128(18): 3635-3645, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38662914

RESUMO

High-field magic angle spinning (MAS) dynamic nuclear polarization (DNP) is becoming a common technique for improving the sensitivity of solid-state nuclear magnetic resonance (SSNMR) by the hyperpolarization of nuclear spins. Recently, we have shown that gamma irradiation is capable of creating long-lived free radicals that are amenable to MAS DNP in quartz and a variety of organic solids. Here, we demonstrate that ball milling is able to generate millimolar concentrations of stable radical species in diverse materials such as polystyrene, cellulose, borosilicate glass, and fused quartz. High-field electron paramagnetic resonance (EPR) was used to obtain further insight into the nature of the radicals formed in ball milled quartz and borosilicate glass. We further show that radicals generated in quartz by ball milling can be used for solid-effect DNP. We obtained 29Si DNP enhancements of approximately 114 and 33 at 110 K and room temperature, respectively, from a sample of ball milled quartz.

4.
Inorg Chem ; 62(21): 8271-8284, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37196103

RESUMO

Glassy solid electrolytes (GSEs) are promising solid electrolytes in the development of all solid-state batteries. Mixed oxy-sulfide nitride (MOSN) GSEs combine the high ionic conductivity of sulfide glasses, the excellent chemical stability of oxide glasses, and the electrochemical stability of nitride glasses. However, the reports on the synthesis and characterization of these novel nitrogen containing electrolytes are quite limited. Therefore, the systematic incorporation of LiPON during glass synthesis was used to explore the effects of nitrogen and oxygen additions on the atomic-level structures in the glass transition (Tg) and crystallization temperature (Tc) of MOSN GSEs. The MOSN GSE series 58.3Li2S + 31.7SiS2 + 10[(1 - x)Li0.67PO2.83 + x LiPO2.53N0.314], x = 0.0, 0.06, 0.12, 0.2, 0.27, 0.36, was prepared by melt-quench synthesis. Differential scanning calorimetry was used to determine the Tg and Tc values of these glasses. Fourier transformation-infrared, Raman, and magic angle spinning nuclear magnetic resonance spectroscopies were used to examine the short-range order structures of these materials. X-ray photoelectron spectroscopy was conducted on the glasses to further understand the bonding environments of the doped nitrogen. Finally, N and S elemental analyses were used to confirm the composition of these GSEs. These results are used to elucidate the structure of these glasses and to understand the thermal property impact oxygen and nitrogen doping in these GSEs.

5.
Inorg Chem ; 61(44): 17469-17484, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36279422

RESUMO

The preparation, properties, and short-range order (SRO) structures of glasses in the series (1-x)[2/3Na2S + 1/3P2S5] + x[1/3Na2S + 2/3NaPO2.31N0.46] = Na4P2S7-6xO4.62xN0.92x, where 0 ≤ x ≤ 0.5 (NaPSON), are reported on. In this study, these mixed oxy-sulfide-nitride (MOSN) glasses were prepared by adding the nitrided material NaPO3-(3/2)yNy; y = 0.46 = NaPO2.31N0.46 (NaPON) to the base sulfide glass Na4P2S7. For comparison purposes, additions of the unitrided material, y = 0, NaPO3, were also studied (NaPSO). Accordingly, large batches of bubble-free glass could be prepared making this route of nitrogen doping amendable toward scaling-up the glass melting process; though, only small amounts of nitrogen could be incorporated in this manner. Nitrogen and sulfur compositional analysis were combined with XPS, Raman, FT-IR, and 31P MAS NMR spectroscopies to determine the amount of retained nitrogen in the glass after melting and quenching and to determine the effect of the added nitrogen and oxygen on the structure of the base pure sulfide glass Na4P2S7, x = 0.0. The nitrogen content increased linearly with the addition of NaPON, but was found, through quantitative 31P MAS NMR analysis, to be approximately half that expected at each value of x. Despite the small amount of nitrogen retained in these glasses, profound increases in the glass transition (Tg) and crystallization temperatures (Tc) were found with increasing x. For the intermediate values of x, 0.2 and 0.3, no crystallization of the supercooled melt was observed even 250 °C above the Tg. It was found that the addition of NaPON to the series caused a disproportionation reaction, where the oxide and oxy-nitride SRO species preferentially formed covalent, networking phosphate chains, forcing the sodium modifier to ionic sulfide units with large fractions of nonbridging sulfurs (NBSs). This disproportionation reaction was also observed in the NaPO3 doped series of glasses, but to a smaller extent. Oxygen was found in both bridging oxygen (BO) and nonbridging oxygen (NBOs) structures while the sulfur was predominantly found in nonbridging sulfur (NBS) structures. N 1s XPS and 31P NMR studies provided insight into the nitrogen bearing phosphorus units and the wt % of nitrogen that was retained in the quenched glasses. It was found that trigonally coordinated nitrogen (Nt) was preferentially retained in the melt, whereas it is proposed that the linearly coordinated (doubly bonded) nitrogen (Nd) accounts for the lost nitrogen in the glasses.

6.
Brain Inj ; 36(8): 931-938, 2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35968581

RESUMO

BACKGROUND: This study investigated the long-term effects of multiple concussions on prefrontal cortex oxygenation using near-infrared spectroscopy (NIRS) during a squat-stand maneuver that activated dynamic cerebral autoregulation. METHODS: Active male retired contact sport athletes with a history of 3+ concussions (mTBI; n = 55), and active retired athletes with no concussion history (CTRL; n = 29) were recruited. Participants completed a 5-min squat-stand maneuve (10-s squat, 10-s stand, 0.05 Hz; 15 times). Oxygenated (O2Hb), deoxygenated (HHb), total (tHb) hemoglobin, and hemoglobin difference (HbDiff) were analyzed through the change in maximal and minimal values during the test (∆MAX), Z-scores, and standard deviations. RESULTS: mTBI group showed left prefrontal cortex O2Hb ∆MAX (p = 0.046) and HbDiff ∆MAX (p = 0.018) were significantly higher. Within-group analyses showed significantly higher left HHb ∆MAX (p = 0.003) and lower left HbDiff Z-scores (p = 0.010) only in the mTBI group. The CTRL group demonstrated significantly lower left HbDiff SD (p = 0.039), tHb Z-scores (p = 0.030), and HbDiff ∆MAX (p = 0.037) compared to right prefrontal cortex response. CONCLUSION: These preliminary results suggest changes in prefrontal cortex oxygenation potentially affecting the brain's ability to adapt to changing cerebral perfusion pressure after multiple previous concussions.


Assuntos
Concussão Encefálica , Atletas , Hemoglobinas/metabolismo , Humanos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho
7.
Inorg Chem ; 60(18): 13968-13981, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34463479

RESUMO

Nitrogen doping has been shown to greatly improve the stability of solid electrolyte (SE) materials at the anode and cathode interfaces in all solid-state batteries (ASSBs) as widely demonstrated by the LiPON family of compositions. In an effort to expand the use of nitrogen in SEs, in this study, mixed oxy-sulfide nitride (MOSN) glasses were prepared by direct ammonolysis of the sodium oxy-sulfide phosphate Na4P2S7-xOx (NaPSO) glass series to understand the combined effects that oxygen and sulfur have on the incorporation of nitrogen. The short-range order (SRO) structures of the Na4P2S(7-x)-3/2yzOx-3/2y(1-z)Ny (NaPSON) glasses were investigated with Raman and infrared (IR) spectroscopies to understand the effect that nitrogen has in the glass structure. The N content of the glasses was quantified by elemental analysis and confirmed through weight change measurements. By combining this information, it was further possible to determine the anion exchange ratio, z, for the N substitution of O and S as a function of the base NaPSO glass chemistry, x. The composition-dependent glass transition temperature, Tg(x), measured with differential scanning calorimetry (DSC), was found to correlate well with the measured N/P ratio, y, in the NaPSON glasses.

8.
Tour Manag ; 82: 104169, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32834313

RESUMO

The global economic value of parks through improved mental health of tourists has been estimated at about ten times greater than direct park tourism expenditure. The Chinese term for this health services value is jing hua xin ling, psychological destressing. Here we present the first case where optimal tourist infrastructure is influenced by including mental health. Using a multi-stage, cross-lingual, differential stakeholder method, we analyse conflicts between road- and roadless-access tourism in the very large new Sanjiangyuan National Park, Qinghai, which offers jing hua xin ling to domestic tourists from eastern-seaboard cities. This provides a powerful tourism attraction, and hence economic opportunity, for the region around the park. If these mental health aspects are included, together with their direct and indirect consequences for tourism, then roadlessness is preferable to new roads. Similar infrastructure conflicts occur for park tourism worldwide, and jing hua xin ling can provide a global theoretical framework.

9.
J Acoust Soc Am ; 147(3): 1681, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32237823

RESUMO

Little information exists on endocrine responses to noise exposure in marine mammals. In the present study, cortisol, aldosterone, and epinephrine levels were measured in 30 bottlenose dolphins (Tursiops truncatus) before and after exposure to simulated U.S. Navy mid-frequency sonar signals (3250-3450 Hz). Control and exposure sessions, each consisting of ten trials, were performed sequentially with each dolphin. While swimming across the experimental enclosure during exposure trials, each dolphin received a single 1-s exposure with received sound pressure levels (SPLs, dB re 1 µPa) of 115, 130, 145, 160, 175, or 185 dB. Blood samples were collected through behaviorally conditioned, voluntary participation of the dolphins approximately one week prior to, immediately following, and approximately one week after exposure were analyzed for hormones via radioimmunoassay. Aldosterone was below detection limits in all samples. Neither cortisol nor epinephrine showed a consistent relationship with received SPL, even though dolphins abandoned trained behaviors after exposure to the highest SPLs and the severity of behavioral changes scaled with SPL. It remains unclear if dolphins interpret high-level anthropogenic sound as stressful, annoying, or threatening and whether behavioral responses to sound can be equated to a physiological (endocrine) response.


Assuntos
Golfinho Nariz-de-Garrafa , Animais , Som
10.
Subst Use Misuse ; 55(11): 1892-1899, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32552308

RESUMO

Background: The US opioid epidemic largely featured deaths from prescribed medications during Wave 1 (1990-2010), but its progression since then has resulted more so from deaths to illegal opioids-such as heroin (Wave 2 - 2010-2013) and fentanyl (Wave 3 - 2013-present). As deaths to illegally manufactured fentanyl have increased, attention to the role of prescribed opioids may be waning. However, the shifting nature of today's opioid epidemic demands we monitor how both legal and illegal drugs are involved in overdose deaths. Objectives: The purpose of our study is to investigate the prescription drug (Rx) records of overdose death decedents to illuminate the continued role of prescribed medications in Wave 3 deaths. Methods: We matched drug overdose death data and prescription drug monitoring data to investigate the prescription drug records (i.e. types of opioids and other medications) of Delaware, USA, decedents who died from a drug overdose death between January 1, 2013, and March 31, 2015 (27 months). Results: Fentanyl decedents differed significantly from other decedents in prescribed medications, including the amount and proximity of opioid and Rx fentanyl prescriptions before death. These relationships held while controlling for demographic characteristics and contributing health conditions. Conclusions: Our findings show a continued presence of Rx opioids in overdose deaths and that those dying from fentanyl had different Rx records than those who died from other drugs. Continued monitoring of Rx drugs, improved toxicology testing and greater data access for more research should follow to inform effective interventions.


Assuntos
Overdose de Drogas , Medicamentos sob Prescrição , Analgésicos Opioides , Delaware , Overdose de Drogas/epidemiologia , Fentanila , Humanos
11.
BMC Cancer ; 19(1): 1030, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675944

RESUMO

BACKGROUND: The lack of predictive biomarkers or test systems contributes to high failure rates of systemic therapy in metastasized colorectal carcinoma, accounting for a still unfavorable prognosis. Here, we present an ex vivo functional assay to measure drug-response based on a tissue slice culture approach. METHODS: Tumor tissue slices of hepatic metastases of nine patients suffering from colorectal carcinoma were cultivated for 72 h and treated with different concentrations of the clinically relevant drugs Oxaliplatin, Cetuximab and Pembrolizumab. Easy to use, objective and automated analysis routines based on the Halo platform were developed to measure changes in proliferative activity and the morphometric make-up of the tumor. Apoptotic indices were assessed semiquantitatively. RESULTS: Untreated tumor tissue slices showed high morphological comparability with the original "in vivo"-tumor, preserving proliferation and stromal-tumor interactions. All but one patients showed a dosage dependent susceptibility to treatment with Oxaliplatin, whereas only two patients showed responses to Cetuximab and Pembrolizumab, respectively. Furthermore, we identified possible non-responders to Cetuximab therapy in absence of RAS-mutations. CONCLUSIONS: This is the first time to demonstrate feasibility of the tissue slice culture approach for metastatic tissue of colorectal carcinoma. An automated readout of proliferation and tumor-morphometry allows for quantification of drug susceptibility. This strongly indicates a potential value of this technique as a patient-specific test-system of targeted therapy in metastatic colorectal cancer. Co-clinical trials are needed to customize for clinical application and to define adequate read-out cut-off values.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Cetuximab/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fígado/patologia , Oxaliplatina/farmacologia , Apoptose , Biomarcadores Farmacológicos , Proliferação de Células , Células Cultivadas , Neoplasias Colorretais/patologia , Estudos de Viabilidade , Humanos , Fígado/efeitos dos fármacos , Neoplasias Hepáticas/secundário , Metástase Neoplásica , Técnicas de Cultura de Órgãos
12.
Eur Radiol ; 29(9): 4776-4782, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30747299

RESUMO

OBJECTIVES: Distinguishing between kidney stones and phleboliths can constitute a diagnostic challenge in patients undergoing unenhanced low-dose CT (LDCT) for acute flank pain. We sought to investigate the accuracy of radiomics and a machine-learning classifier in differentiating between kidney stones and phleboliths on LDCT. METHODS: Radiomics features were extracted following a semi-automatic segmentation of kidney stones and phleboliths for two independent consecutive cohorts of patients undergoing LDCT for acute flank pain. Radiomics features from the first cohort of patients (n = 369) were ultimately used to train a machine-learning model designed to distinguish kidney stones (n = 211) from phleboliths (n = 201). Classification performance was assessed on the second independent cohort (i.e., testing set) (kidney stones n = 24; phleboliths n = 23) using positive and negative predictive values (PPV and NPV), area under the receiver operating curves (AUC), and permutation testing. RESULTS: Our machine-learning classification model trained on radiomics features achieved an overall accuracy of 85.1% on the independent testing set, with an AUC of 0.902, PPV of 81.5%, and NPV of 90.0%. Classification accuracy was significantly better than chance on permutation testing (p < 0.05, permutation p value). CONCLUSION: Radiomics and machine learning enable accurate differentiation between kidney stones and phleboliths on LDCT in patients presenting with acute flank pain. KEY POINTS: • Combining a machine-learning algorithm with radiomics features extracted for abdominopelvic calcification on LDCT offers a highly accurate method for discriminating phleboliths from kidney stones. • Our radiomics and machine-learning model proved robust for CT acquisition and reconstruction protocol when tested in comparison with an external independent cohort of patients with acute flank pain. • The high performance of the radiomics-based automatic classification model in differentiating phleboliths from kidney stones indicates its potential as a future diagnostic tool for equivocal abdominopelvic calcifications in the setting of suspected renal colic.


Assuntos
Cálculos Renais/diagnóstico por imagem , Litíase/diagnóstico por imagem , Aprendizado de Máquina , Tomografia Computadorizada por Raios X/métodos , Dor Aguda/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Diagnóstico Diferencial , Feminino , Dor no Flanco/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Pediatr Blood Cancer ; 65(3)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29115708

RESUMO

BACKGROUND: Vincristine (VCR) is a critical part of treatment in pediatric malignancies and is associated with dose-dependent peripheral neuropathy (vincristine-induced peripheral neuropathy [VIPN]). Our previous findings show VCR metabolism is regulated by the CYP3A5 gene. Individuals who are low CYP3A5 expressers metabolize VCR slower and experience more severe VIPN as compared to high expressers. Preliminary observations suggest that Caucasians experience more severe VIPN as compared to nonCaucasians. PROCEDURE: Kenyan children with cancer who were undergoing treatment including VCR were recruited for a prospective cohort study. Patients received IV VCR 2 mg/m2 /dose with a maximum dose of 2.5 mg as part of standard treatment protocols. VCR pharmacokinetics (PK) sampling was collected via dried blood spot cards and genotyping was conducted for common functional variants in CYP3A5, multi-drug resistance 1 (MDR1), and microtubule-associated protein tau (MAPT). VIPN was assessed using five neuropathy tools. RESULTS: The majority of subjects (91%) were CYP3A5 high-expresser genotype. CYP3A5 low-expresser genotype subjects had a significantly higher dose and body surface area normalized area under the curve than CYP3A5 high-expresser genotype subjects (0.28 ± 0.15 hr·m2 /l vs. 0.15 ± 0.011 hr·m2 /l, P = 0.027). Regardless of which assessment tool was utilized, minimal neuropathy was detected in this cohort. There was no difference in the presence or severity of neuropathy assessed between CYP3A5 high- and low-expresser genotype groups. CONCLUSION: Genetic factors are associated with VCR PK. Due to the minimal neuropathy observed in this cohort, there was no demonstrable association between genetic factors or VCR PK with development of VIPN. Further studies are needed to determine the role of genetic factors in optimizing dosing of VCR for maximal benefit.


Assuntos
Citocromo P-450 CYP3A , Genótipo , Neoplasias , Doenças do Sistema Nervoso Periférico , Vincristina , Adolescente , Criança , Pré-Escolar , Citocromo P-450 CYP3A/biossíntese , Citocromo P-450 CYP3A/genética , Feminino , Humanos , Lactente , Quênia , Masculino , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/genética , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/enzimologia , Doenças do Sistema Nervoso Periférico/genética , Testes Farmacogenômicos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/farmacocinética
14.
Inorg Chem ; 57(1): 72-81, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29257681

RESUMO

The composition dependence of the short-range order (SRO) structure in highly modified mixed glass former sodium thiosilicophosphate glasses, yNa2S + (1 - y)[xSiS2 + (1 - x)PS5/2], were investigated using infrared (IR), Raman, and 29Si and 31P magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopies. Both the y = 0.5 and 0.67 glasses undergo disproportionation reactions among the Si and P SRO structures, which lead to various and complex SRO structural units for the Si and P, as shown via the spectra used to characterize the glasses. In the y = 0.5 series, the compositionally expected and experimentally observed SRO units are the P1 and Si2 units in the two binary end-member glasses, where the superscript is the number of bridging sulfur atoms on the P or Si units. However, in the ternary mixed glasses, 0 < x < 1, these units were found to react to form P0 (more highly modified, y = 0.60) and Si3 (less highly modified, y = 0.33) units, indicating preferential association of Na+ ions with the P SRO structures. The Raman spectra were used to resolve the heretofore incompletely studied Si3 SRO unit, which was otherwise difficult to elucidate using 29Si MAS NMR alone. In the y = 0.67 series glasses, the expected P0 and Si0 SRO units were observed for the end-member binary glasses. Like in the y = 0.5 series, the 29Si MAS NMR showed that edge-sharing Si2 (ESi2, y = 0.5) structures were also present in these highly modified glasses, which meant Na2S was not completely incorporated in the network. Evidence of this was shown in the Raman spectra in the form of polysulfide structures Na2Sx (x = 2, 4).

15.
Phys Chem Chem Phys ; 20(3): 1629-1641, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29261212

RESUMO

Glasses are promising candidate materials for all-solid-state electrolytes for rechargeable batteries due to their outstanding mechanical stability, wide electrochemical stability range, and open structure for potentially high conductivity. Mechanical stiffness and ionic conductivity are two key parameters for solid-state electrolytes. In this study, we investigate two mixed-network former glass systems, sodium borosilicate 0.2Na2O + 0.8[xBO1.5 + (1 - x)SiO2] and sodium borogermanate 0.2Na2O + 0.8[xBO1.5 + (1 - x)GeO2] glasses. With mixed-network formers, the structure of the network changes while the network modifier mole fraction is kept constant, i.e., x = 0.2, which allows us to analyze the effect of the network structure on various properties, including ionic conductivity and elastic properties. Besides the non-linear, non-additive mixed glass former effect, we find that the longitudinal, shear and Young's moduli depend on the combined number density of tetrahedrally and octahedrally coordinated network former elements. These units provide connectivity in three dimensions, which is required for the networks to exhibit restoring forces in response to isotropic and shear deformations. Moreover, the activation energy for modifier cation, Na+, migration is strongly correlated with the bulk modulus, suggesting that the elastic strain energy associated with the passageway dilation for the sodium ions is governed by the bulk modulus of the glass. The detailed analysis provided here gives an estimate for the number of atoms in the vicinity of the migrating cation that are affected by elastic deformation during the activated process. The larger this number and the more compliant the glass network, the lower is the activation energy for the cation jump.

16.
Eur Radiol ; 27(7): 2950-2956, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27847999

RESUMO

OBJECTIVES: To prospectively evaluate the impact of iterative reconstruction (IR) algorithms on pulmonary emphysema assessment as compared to filtered back projection (FBP). METHODS: One hundred ten unenhanced chest CT examinations were obtained on two different scanners. Image reconstructions from a single acquisition were done with different levels of IR and compared with FBP on the basis of the emphysema index (EI), lung volume and voxel densities. Objective emphysema assessment was performed with 3D software provided by each manufacturer. Subjective assessment of emphysema was performed as a blinded evaluation. Quantitative and subjective values were compared using repeated ANOVA analysis, Bland-Altman analysis and Kendall's coefficient of concordance (W). RESULTS: Lung volumes are stable on both units, throughout all IR levels (P ≥ 0.057). EI significantly decreases on both units with the use of any level of IR (P < 0.001). The highest levels of IR are responsible for a decrease of 33-36 % of EI. Significant differences in minimal lung density are found between the different algorithms (P < 0.003). Intra- and inter-reader concordance for emphysema characterisation is generally good (W ≥ 0.77 and W ≥ 0.86, respectively). CONCLUSIONS: Both commercially available IR algorithms used in this study significantly changed EI but did not alter visual assessment compared to standard FBP reconstruction at identical radiation exposure. KEY POINTS: • Objective quantification of pulmonary emphysema is sensitive to iterative reconstructions • Subjective evaluation of pulmonary emphysema is not influenced by iterative reconstructions • Consistency in reconstruction algorithms is of paramount importance for pulmonary emphysema monitoring.


Assuntos
Algoritmos , Enfisema Pulmonar/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Software
17.
Phys Chem Chem Phys ; 19(24): 15942-15952, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28593205

RESUMO

Elastic properties of alkali containing glasses are of great interest not only because they provide information about overall structural integrity but also they are related to other properties such as thermal conductivity and ion mobility. In this study, we investigate two mixed-network former glass systems, sodium borosilicate 0.2Na2O + 0.8[xBO1.5 + (1 - x)SiO2] and sodium borogermanate 0.2Na2O + 0.8[xBO1.5 + (1 - x)GeO2] glasses. By mixing network formers, the network topology can be changed while keeping the network modifier concentration constant, which allows for the effect of network structure on elastic properties to be analyzed over a wide parametric range. In addition to non-linear, non-additive mixed-glass former effects, maxima are observed in longitudinal, shear and Young's moduli with increasing atomic number density. By combining results from NMR spectroscopy and Brillouin light scattering with a newly developed statistical thermodynamic reaction equilibrium model, it is possible to determine the relative proportions of all network structural units. This new analysis reveals that the structural characteristic predominantly responsible for effective mechanical load transmission in these glasses is a high density of network cations coordinated by four or more bridging oxygens, as it provides for establishing a network of covalent bonds among these cations with connectivity in three dimensions.

18.
Ethn Health ; 22(5): 510-527, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27764959

RESUMO

OBJECTIVES: Latina women are disproportionately affected by HIV in the US, and account for 30% of all HIV infections in Miami-Dade County, Florida. The main risk for Latina women is heterosexual contact. Little is known about the relational and cultural factors that may impact women's HIV risk perception. This study aims to describe Latina women's perception of their HIV risk within a relational, cultural, and linguistic context. DESIGN: Eight focus groups of Latina women (n = 28), four English speaking groups and four Spanish speaking groups, were conducted between December 2013 and May 2014. Women were recruited from a diversion program for criminal justice clients and by word of mouth. Eligibility criteria included the following: self-identify as Hispanic/Latino, 18-49 years of age, and self-identify as heterosexual. A two-level open coding analytic approach was conducted to identify themes across groups. RESULTS: Most participants were foreign-born (61%) and represented the following countries: Cuba (47%), Honduras (17.5%), Mexico (12%), as well as Nicaragua, Puerto Rico, Colombia, and Venezuela (15%). Participant ages ranged between 18 and 49, with a mean age of 32 years. Relationship factors were important in perceiving HIV risk including male infidelity, women's trust in their male partners, relationship type, and getting caught up in the heat of the moment. For women in the English speaking groups, drug use and trading sex for drugs were also reasons cited for putting them at risk for HIV. English speaking women also reported that women should take more responsibility regarding condom use. CONCLUSION: Findings emphasize the importance of taking relational and cultural context into account when developing HIV prevention programs for Latina women. Interventions targeting English speaking Latina women should focus on women being more proactive in their sexual health; interventions focused on Spanish speaking women might target their prevention messages to either men or couples.


Assuntos
Características Culturais , Infecções por HIV/prevenção & controle , Hispânico ou Latino/psicologia , Amor , Confiança , Adulto , Preservativos/estatística & dados numéricos , Emigrantes e Imigrantes/estatística & dados numéricos , Feminino , Florida , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Parceiros Sexuais
19.
J Strength Cond Res ; 31(10): 2740-2747, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28195971

RESUMO

The purpose of this study was to determine the relationship between Functional Movement Screen (FMS) score and the risk of time-loss injury in experienced male rugby union athletes. A secondary purpose was to determine the relationship between FMS-determined asymmetries and the risk of time-loss injury in these athletes. Functional Movement Screen scores were collected from male rugby union athletes (n = 73) during preseason and half-way through one 8-month season. Time-loss injury data were collected throughout the full season. A receiver-operator characteristic curve was created for each half of the season to identify FMS composite and asymmetry cut-off scores associated with increased likelihood of injury and determined odds ratios, sensitivity, and specificity in evaluating FMS as a predictor of injury risk. Odds ratio analyses revealed that when compared with those scoring >14, athletes with an FMS ≤14 were 10.42 times more likely (95% confidence interval [CI]: 1.28-84.75, p = 0.007) to have sustained injury in the first half of the season and 4.97 times (95% CI: 1.02-24.19, p = 0.029) more likely in the second half of the season. The presence of asymmetries was not associated with increased likelihood of injury. Experienced male rugby union athletes with FMS composite scores ≤14 are significantly more likely to sustain time-loss injury in a competitive season than those scoring >14. The quality of fundamental movement, as assessed by the FMS, is predictive of time-loss injury risk in experienced rugby union athletes and should be considered an important preseason assessment tool used by strength and conditioning and medical professionals in this sport with inherently high injury rates.


Assuntos
Traumatismos em Atletas/epidemiologia , Teste de Esforço/métodos , Futebol Americano/lesões , Movimento/fisiologia , Adulto , Atletas , Humanos , Masculino , Razão de Chances , Curva ROC , Risco , Fatores de Tempo , Adulto Jovem
20.
Cerebrovasc Dis ; 42(1-2): 57-65, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26986943

RESUMO

BACKGROUND: With regard to acute stroke, patients with unknown time from stroke onset are not eligible for thrombolysis. Quantitative diffusion weighted imaging (DWI) and fluid attenuated inversion recovery (FLAIR) MRI relative signal intensity (rSI) biomarkers have been introduced to predict eligibility for thrombolysis, but have shown heterogeneous results in the past. In the present work, we investigated whether the inclusion of easily obtainable clinical-radiological parameters would improve the prediction of the thrombolysis time window by rSIs and compared their performance to the visual DWI-FLAIR mismatch. METHODS: In a retrospective study, patients from 2 centers with proven stroke with onset <12 h were included. The DWI lesion was segmented and overlaid on ADC and FLAIR images. rSI mean and SD, were calculated as follows: (mean ROI value/mean value of the unaffected hemisphere). Additionally, the visual DWI-FLAIR mismatch was evaluated. Prediction of the thrombolysis time window was evaluated by the area-under-the-curve (AUC) derived from receiver operating characteristic (ROC) curve analysis. Factors such as the association of age, National Institutes of Health Stroke Scale, MRI field strength, lesion size, vessel occlusion and Wahlund-Score with rSI were investigated and the models were adjusted and stratified accordingly. RESULTS: In 82 patients, the unadjusted rSI measures DWI-mean and -SD showed the highest AUCs (AUC 0.86-0.87). Adjustment for clinical-radiological covariates significantly improved the performance of FLAIR-mean (0.91) and DWI-SD (0.91). The best prediction results based on the AUC were found for the final stratified and adjusted models of DWI-SD (0.94) and FLAIR-mean (0.96) and a multivariable DWI-FLAIR model (0.95). The adjusted visual DWI-FLAIR mismatch did not perform in a significantly worse manner (0.89). ADC-rSIs showed fair performance in all models. CONCLUSIONS: Quantitative DWI and FLAIR MRI biomarkers as well as the visual DWI-FLAIR mismatch provide excellent prediction of eligibility for thrombolysis in acute stroke, when easily obtainable clinical-radiological parameters are included in the prediction models.


Assuntos
Imagem de Difusão por Ressonância Magnética , Fibrinolíticos/administração & dosagem , Acidente Vascular Cerebral/diagnóstico por imagem , Terapia Trombolítica , Tempo para o Tratamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Circulação Cerebrovascular , Distribuição de Qui-Quadrado , Tomada de Decisão Clínica , Esquema de Medicação , Feminino , Alemanha , Humanos , Interpretação de Imagem Assistida por Computador , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Seleção de Pacientes , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo
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