Dynamic parallel phase-shifting electronic speckle pattern interferometer.

Methods for measuring variations in diffuse surfaces using electronic speckle pattern interferometry (ESPI) are widely used and well known. In this research, we present an out-of-plane ESPI system coupled to a Michelson configuration to generate simultaneous parallel interferograms with different phase shifts. The system uses circular polarization states to generate parallel phase shifted interferograms. Due to the polarization states, the fringes do not experience a contrast reduction, thus avoiding measurement errors that affect spatial or temporal phase-shifting in interferometry. The basic operating principle of polarization modulation is described, and results that represent the temporal evolution of an aluminum plate are presented. The generation of two simultaneous patterns allows one to track the dynamic performance of the plate.

Phase stepping through polarizing modulation in electronic speckle pattern interferometry.

We have demonstrated a speckle out-of-plane interferometer that employs phase-stepping procedures by means of polarization modulation. The system generates circular polarization states with opposite signs at each arm of the system, which overlap at the output of the interferometer, to generate phase shifts operating a conventional linear polarizer; the emerging polarization states have been analyzed to obtain the shifts needed to process the optical phase. The phase-stepping technique is demonstrated with a two-step algorithm to measure out-of-plane displacement on a flat metal plate.

Application of speckle interferometry to the mechanical characterization of a biopolymer sample.

In this work, we present an optical and mechanical characterization of the behavior of an inhomogeneous biopolymer sample through the use of an in-plane electronic speckle pattern interferometer with a pulling system along the $y$y direction. The characterization of the sample subjected to stress comprised the acquisition of speckle patterns for 1360 states. Displacement maps and their corresponding strain maps were computed for every state. Since the information of the maps changes with size due to the sample being pulled at the upper end while it is clamped at the lower end, a scaling method to relate the maps to each other, point-to-point, is presented. The method allows the correct evaluation of sequential strain maps, which depicts the mechanical evolution of the material. Upon managing to relate the strain maps, it is possible to extract strain values for zones of interest from every map in order to build the respective stress-strain curves. Three stress-strain curves associated with three zones in the sample (upper, middle, and bottom) are constructed. When sequential displacement and deformation maps are optically obtained by the interferometer, we present a full-field characterization, along with the obtention stress-strain curves associated with the three zones of strain maps. The curves represent the inhomogeneous performance of the sample. Three different elastic moduli (${E_u} = 2.59\;{\rm MPa}$Eu=2.59MPa, ${E_m} = 1.97\;{\rm MPa}$Em=1.97MPa, and ${E_{b}} = 1.67\;{\rm MPa}$Eb=1.67MPa), associated with three respective zones, were obtained. The experimental results for a biopolymer sample here presented show that the technique, in conjunction with the scaling method, is a novel proposal to characterize inhomogeneous materials.

Relative error in out-of-plane measurement due to the object illumination.

In this work the sensitivity vector is analyzed for collimated and divergent oblique illumination for an out-of-plane arrangement. In the case of collimated illumination, the variation of the sensitivity vector components was considered and a geometric model was proposed for its evaluation. The geometry of the optical setup used allowed us to find sensitivity mostly along the pulling direction; the other two components of the sensitivity vector were relatively small. We measured the displacement induced only along the pulling direction. Errors in the displacement measurement associated with divergent and collimated illumination can be predicted when the sensitivity vector is considered constant. Experimental and theoretical results are presented for the out-of-plane electronic speckle pattern interferometer. The analyzed object was an aluminum plate.

Influence of blue maize flour on gluten-free pasta quality and antioxidant retention characteristics.

Due to its bioactive compounds, blue maize flour is a valuable ingredient for developing gluten-free products. The incorporation of alternative flours into gluten-free pasta is a challenge as it usually results in products that, despite their enhanced nutraceutical features, show reduced quality characteristics. Composite pasta was prepared with variable (25, 50 and 75%) contents of flours from white and blue maize, chickpea and unripe plantain, following a laboratory-scale process. The composite pasta exhibited acceptable cooking loss (9-11%); pasta with blue maize showed lower hardness and chewiness, but higher adhesiveness than its white maize-based counterpart. Blue maize-based pasta presented dark color. The addition of blue maize flour at 75% conveyed the highest total phenolic content retention after extrusion (80%) and cooking (70%). Pasting profile of blue maize pasta (50 and 75%) showed a defined second viscosity peak due to re-arrangement of starch components upon cooling. The observed retention of phenolic compounds with antioxidant capacity after cooking will be useful for further development (selection of ingredients, formulations and conditions of operation) of gluten-free products with potential health benefits.

Starch and antioxidant compound release during in vitro gastrointestinal digestion of gluten-free pasta.

The microstructure of cooked gluten-free pasta depends on the ingredients used, and this microstructure affects the starch hydrolysis (SH), the release of phenolic compounds (PC) and their antioxidant capacity (AC). The aim of this study was to evaluate the SD and bioaccessibility of PC during in vitro gastrointestinal digestion of gluten-free pasta and its relationship with the microstructure. The highest SH was during the intestinal phase (≈60%), but pasta with the highest content of unripe plantain and chickpea presented the lowest release of PC (≈60%). The insoluble dietary fibre could be responsible (≈12.5%) for these effects. The cooked pasta showed high AC in the intestinal phase. Regions with gelatinized starch granules in a less dense protein network and other regions with intact or swollen granules surrounded by a protein network were observed. The starch digestion and bioaccessibility of PC were related to the structure of the matrix.

Multivariable Analysis of Gluten-Free Pasta Elaborated with Non-Conventional Flours Based on the Phenolic Profile, Antioxidant Capacity and Color.

The phenolic compounds, color and antioxidant capacity of gluten-free pasta prepared with non-conventional flours such as chickpea (CHF), unripe plantain (UPF), white maize (WMF) and blue maize (BMF) were analyzed. Fifteen phenolic compounds (five anthocyanins, five hydroxybenzoic acids, three hydroxycinnamic acids, one hydroxyphenylacetic acid and one flavonol) were identified in pasta prepared with blue maize, and 10 compounds were identified for samples prepared with white maize. The principal component analysis (PCA) led to results describing 98% of the total variance establishing a clear separation for each pasta. Both the proportion (25, 50 and 75%) and type of maize flour (white and blue) affected the color parameters (L*, C ab *, h ab and ΔE* ab ) and antioxidant properties (DPPH, ABTS and FRAP methods) of samples, thus producing gluten-free products with potential health benefits intended for general consumers (including the population with celiac disease).

Life Expectancy and Metastatic Spine Scoring Systems: An Academic Institutional Experience.

STUDY DESIGN: A retrospective data collection study with application of metastatic spine scoring systems. OBJECTIVES: To apply the Tomita and revised Tokuhashi scoring systems to a surgical cohort at a single academic institution and analyze spine-related surgical morbidity and mortality rates. SUMMARY OF BACKGROUND DATA: Surgical management of metastatic spine patients requires tools that can accurately predict patient survival, as well as knowledge of morbidity and mortality rates. METHODS: An Oregon Health & Science University (OHSU) Spine Center surgical database was queried (years 2002-2010) to identify patients with an ICD-9 code indicative of metastatic spine disease. Patients whose only surgical treatment was vertebral augmentation were not included. Scatter plots of survival versus the Tomita and revised Tokuhashi metastatic spine scoring systems were statistically analyzed. Spine-related morbidity and mortality rates were calculated. RESULTS: Sixty-eight patients were identified: 45 patients' (30 male patients, mean age 45 y) medical records included operative, morbidity, and mortality statistic data and 38 (26 male patients, mean age 54 y) contained complete metastatic spine scoring system data. Of the 38 deceased spine metastatic patients, 8 had renal cell, 7 lung, 4 breast, 2 chondrosarcoma, 2 prostate, 11 other, and 4 unknown primary cancers. Linear regression analysis revealed R values of 0.2570 and 0.2009 for the revised Tokuhashi and Tomita scoring systems, respectively. Overall transfusion, infection, morbidity, and mortality rates were 33% and 9%, and 42% and 9%, respectively. CONCLUSIONS: Application of metastatic prognostic scoring systems to a retrospective surgical cohort revealed an overall poor correlation with the Tomita and revised Tokuhashi predictive survival models. Morbidity and mortality rates concur with those in the medical literature. This study underscores the difficulty in utilizing metastatic spine scoring systems to predict patient survival. We believe a scoring system based on cancer type is needed to account for changes in treatment paradigms with improved patient survival over time.

Upfront boost Gamma Knife "leading-edge" radiosurgery to FLAIR MRI-defined tumor migration pathways in 174 patients with glioblastoma multiforme: a 15-year assessment of a novel therapy.

OBJECTIVE Glioblastoma multiforme (GBM) is composed of cells that migrate through the brain along predictable white matter pathways. Targeting white matter pathways adjacent to, and leading away from, the original contrast-enhancing tumor site (termed leading-edge radiosurgery [LERS]) with single-fraction stereotactic radiosurgery as a boost to standard therapy could limit the spread of glioma cells and improve clinical outcomes. METHODS Between December 2000 and May 2016, after an initial diagnosis of GBM and prior to or during standard radiation therapy and carmustine or temozolomide chemotherapy, 174 patients treated with radiosurgery to the leading edge (LE) of tumor cell migration were reviewed. The LE was defined as a region outside the contrast-enhancing tumor nidus, defined by FLAIR MRI. The median age of patients was 59 years (range 22-87 years). Patients underwent LERS a median of 18 days from original diagnosis. The median target volume of 48.5 cm3 (range 2.5-220.0 cm3) of LE tissue was targeted using a median dose of 8 Gy (range 6-14 Gy) at the 50% isodose line. RESULTS The median overall survival was 23 months (mean 43 months) from diagnosis. The 2-, 3-, 5-, 7-, and 10-year actual overall survival rates after LERS were 39%, 26%, 16%, 10%, and 4%, respectively. Nine percent of patients developed treatment-related imaging-documented changes due to LERS. Nineteen percent of patients were hospitalized for management of edema, 22% for resection of a tumor cyst or new tumor bulk, and 2% for shunting to treat hydrocephalus throughout the course of their disease. Of the patients still alive, Karnofsky Performance Scale scores remained stable in 90% of patients and decreased by 1-3 grades in 10% due to symptomatic treatment-related imaging changes. CONCLUSIONS LERS is a safe and effective upfront adjunctive therapy for patients with newly diagnosed GBM. Limitations of this study include a single-center experience and single-institution determination of the LE tumor target. Use of a leading-edge calculation algorithm will be described to achieve a consistent approach to defining the LE target for general use. A multicenter trial will further elucidate its value in the treatment of GBM.

Effect on in vitro starch digestibility of Mexican blue maize anthocyanins.

The purpose of this study was to evaluate the effect of blue maize extracts obtained by acid-methanol treatment on the nutritional in vitro starch fractions such as: rapidly digestive starch (RDS), slowly digestive starch (SDS) and resistant starch (RS) of native and gelatinized commercial maize starch. Chromatographic analysis (HPLC-DAD/ESI-MS) of blue maize extracts showed the presence of seven anthocyanins, where cyanidin-3-(6″-malonylglucoside) was the main. Blue maize extracts modified nutritional in vitro starch fractions (decrease of RDS) while RS content increased (1.17 and 2.02 times for native and gelatinized commercial maize starch, respectively) when anthocyanins extracts were added to starch up to 75% (starch weight). This preliminary observation provides the basis for further suitability evaluation of blue maize extract as natural starch-modifier by the possible anthocyanins-starch interaction. Anthocyanin extracts can be a suitable to produce functional foods with higher RS content with potential human health benefits.

Imaging characteristic analysis of metastatic spine lesions from breast, prostate, lung, and renal cell carcinomas for surgical planning: Osteolytic versus osteoblastic.

BACKGROUND: Surgeons treating metastatic spine disease can use computed tomography (CT) imaging to determine whether lesions are osteolytic, osteoblastic, or mixed. This enables treatment that considers the structural integrity of the vertebral body (VB), which is impaired with lytic lesions but not blastic lesions. The authors analyzed CT imaging characteristics of spine metastasis from breast, lung, prostate, and renal cell carcinomas (RCCs) to determine the metastasis patterns of each of these common tumors. METHODS: The authors identified patients with metastatic spine disease treated during a 3-year period. Variables studied included age, sex, and cancer type. Lesions from breast, lung, prostate, and RCC primary lesions were selected for imaging analysis. RESULTS: Sixty-six patients were identified: 17 had breast metastasis, 14 prostate, 18 lung, and 17 RCC. Breast cancer metastasis involved 33% of VBs with 56%, 20%, and 24% osteolytic, osteoblastic, and mixed, respectively. Prostate cancer metastasis involved 35% of VBs with 14%, 62%, and 24% osteolytic, osteoblastic, and mixed, respectively. Lung cancer metastasis involved 13% of VBs with 64%, 33%, and 3% osteolytic, osteoblastic, and mixed, respectively. RCC metastasis involved 11% of VBs with 91%, 7%, and 2% osteolytic, osteoblastic, and mixed lesions, respectively. CONCLUSIONS: To improve surgical planning, we advocate the use of CT prior to surgery to evaluate whether spine metastases are osteolytic or osteoblastic. In cases of osteolytic lesions, the concern is of segmental instability requiring reconstruction and the risk for screw pull out should instrumentation be considered. In cases of osteoblastic lesions, surgeons should consider debulking dense bone.

Comparative Study of Phenolic Profile, Antioxidant Capacity, and Color-composition Relation of Roselle Cultivars with Contrasting Pigmentation.

Roselle is a plant that accumulates anthocyanins significantly, hence its importance as food coloring and as a source of antioxidant compounds for human health. This study was aimed to determine phenolic composition and antioxidant capacity of methanolic extracts, and beverages obtained from native roselle cultivars in Mexico (Negra, Sudan, Rosa and Blanca) with different degrees of pigmentation, and to establish the color-composition relationship. Chromatographic methods were used to determine phenolic compounds: flavanols, flavonols, benzoic, hibiscus and phenolic acids as well as two main anthocyanins (cyanidin 3-sambubioside and delphinidin 3-sambubioside). The antioxidant capacity was evaluated by ABTS and FRAP assays. Tristimulus colorimetry showed to be a useful technique to determine the color-composition relationship, leading to equations that allowed to predict anthocyanin content of roselle (R > 0.84). Also, a stepwise linear discriminant analysis (SLDA) was developed in order to classify roselle cultivars. The obtained mathematical model could be an important tool to be used in colorimetric characterization of functional compounds used in food processing.