keyword
MENU ▼
Read by QxMD icon Read
search

Experimental techniques

keyword
https://www.readbyqxmd.com/read/28346884/automatic-measurement-of-melanoma-depth-of-invasion-in-skin-histopathological-images
#1
Hongming Xu, Richard Berendt, Naresh Jha, Mrinal Mandal
Measurement of melanoma depth of invasion (DoI) in skin tissues is of great significance in grading the severity of skin disease and planning patient's treatment. However, accurate and automatic measurement of melanocytic tumor depth is a challenging problem mainly due to the difficulty of skin granular identification and melanoma detection. In this paper, we propose a technique for measuring melanoma DoI in microscopic images digitized from MART1 (i.e., meleanoma-associated antigen recognized by T cells) stained skin histopathological sections...
March 10, 2017: Micron: the International Research and Review Journal for Microscopy
https://www.readbyqxmd.com/read/28346777/the-effect-of-intrinsic-disorder-and-self-association-on-the-translational-diffusion-of-proteins-the-case-of-%C3%AE-casein
#2
Daria L Melnikova, Vladimir Dmitrievich Skirda, Irina V Nesmelova
Translational diffusion is the major mode of macromolecular transport in leaving organisms and therefore it is vital to many biological and biotechnological processes. Although translational diffusion of proteins has received considerable theoretical and experimental scrutiny, much of that attention has been directed towards the description of globular proteins. The translational diffusion of intrinsically disordered proteins (IDPs), however, is much less studied. Here, we use a pulsed-gradient nuclear magnetic resonance technique (PFG NMR) to investigate the translational diffusion of a disordered protein in a wide range of concentrations using α-casein that belongs to the class of natively disordered proteins as an example...
March 27, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28346078/molecular-dynamics-simulation-of-three-plastic-additives-diffusion-in-polyethylene-terephthalate
#3
Bo Li, Zhi-Wei Wang, Qin-Bao Lin, Chang-Ying Hu
Accurate diffusion coefficient data of additives in polymer is of paramount importance for estimating the migration of the additives over time. In this article it is shown how this diffusion coefficient can be estimated for three plastic additives [2-(2'-hydroxy-5'-methylphenyl) (UV-P), 2, 6-di-tert-butyl-4-methylphenol (BHT) and di-(2-ethylhexyl) phthalate (DEHP)] in polyethylene terephthalate (PET) using the molecular dynamics (MD) simulation method. MD simulations were performed at temperatures of 293-433 K...
March 27, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28345879/vibrational-probes-from-small-molecule-solvatochromism-theory-and-experiments-to-applications-in-complex-systems
#4
Bartosz Błasiak, Casey H Londergan, Lauren J Webb, Minhaeng Cho
The vibrational frequency of a chosen normal mode is one of the most accurately measurable spectroscopic properties of molecules in condensed phases. Accordingly, infrared absorption and Raman scattering spectroscopy have provided valuable information on both distributions and ensemble-average values of molecular vibrational frequencies, and these frequencies are now routinely used to investigate structure, conformation, and even absolute configuration of chemical and biological molecules of interest. Recent advancements in coherent time-domain nonlinear vibrational spectroscopy have allowed the study of heterogeneous distributions of local structures and thermally driven ultrafast fluctuations of vibrational frequencies...
March 27, 2017: Accounts of Chemical Research
https://www.readbyqxmd.com/read/28345726/structural-analyses-of-isolated-cyclic-tetrapeptides-with-varying-amino-acid-residues
#5
A Stamm, D Maué, A Schaly, S Schlicher, J Bartl, S Kubik, M Gerhards
Cyclic peptides represent a large class of substances that occur in nature with important biological and medical functions. Synthetic cyclic peptides are used as artificial receptors due to a series of advantages over conventional receptors. In order to optimize their binding abilities, investigations of their intrinsic structural properties especially with regard to the influence of different amino acid residues are fundamental. Here we report the structural analysis of two synthetic cyclic tetrapeptides cyclo[l-Tyr(Me)-d-Pro-l-Ala-d-Pro] (CPAla) and cyclo[l-Tyr(Me)-d-Pro-l-Glu(Me)-d-Pro] (CPGlu) in a molecular beam by means of combined IR/UV spectroscopic techniques...
March 27, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28345535/photoactivated-processes-in-optical-fibers-generation-and-conversion-mechanisms-of-twofold-coordinated-si-and-ge-atoms
#6
Luigi Giacomazzi, Layla Martin-Samos, Aziz Boukenter, Youcef Ouerdane, Sylvain Girard, Antonino Alessi, Nicolas Richard, Stefano de Gironcoli
In this work we present an extensive investigation of nanoscale physical phenomena related to oxygen-deficient centers (ODC) in silica and Ge-doped silica by means of first-principles calculations, including nudged-elastic band (NEB), electron paramagnetic resonance (EPR) parameters calculations, and many-body perturbation theory (GW and Bethe-Salpeter Equation) techniques. We show that by neutralizing positively charged oxygen monovacancies we can obtain model structures of twofold Si and Ge defects of which the calculated absorption spectra and singlet-to-triplet transitions are in excellent agreement with the experimental optical absorption and photo-luminescence data...
March 27, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28345452/l-glutamine-supplementation-promotes-an-improved-energetic-balance-in-walker-256-tumor-bearing-rats
#7
Heber Amilcar Martins, Roberto Barbosa Bazotte, Geraldo Emilio Vicentini, Mariana Machado Lima, Flavia Alessandra Guarnier, Catchia Hermes-Uliana, Flavia Cristina Vieira Frez, Gleison Daion Piovezana Bossolani, Luciane Fracaro, Larissa Dos Santos Fávaro, Mariana Inocêncio Manzano, Jacqueline Nelisis Zanoni
We evaluated the effects of supplementation with oral l-glutamine in Walker-256 tumor-bearing rats. A total of 32 male Wistar rats aged 54 days were randomly divided into four groups: rats without Walker-256 tumor, that is, control rats (C group); control rats supplemented with l-glutamine (CG group); Walker-256 tumor rats without l-glutamine supplementation (WT group); and WT rats supplemented with l-glutamine (WTG group). l-Glutamine was incorporated into standard food at a proportion of 2 g/100 g (2%). After 10 days of the experimental period, the jejunum and duodenum were removed and processed...
March 2017: Tumour Biology: the Journal of the International Society for Oncodevelopmental Biology and Medicine
https://www.readbyqxmd.com/read/28344971/how-to-train-a-cell-cutting-edge-molecular-tools
#8
REVIEW
Jakub Czapiński, Michał Kiełbus, Joanna Kałafut, Michał Kos, Andrzej Stepulak, Adolfo Rivero-Müller
In biological systems, the formation of molecular complexes is the currency for all cellular processes. Traditionally, functional experimentation was targeted to single molecular players in order to understand its effects in a cell or animal phenotype. In the last few years, we have been experiencing rapid progress in the development of ground-breaking molecular biology tools that affect the metabolic, structural, morphological, and (epi)genetic instructions of cells by chemical, optical (optogenetic) and mechanical inputs...
2017: Frontiers in Chemistry
https://www.readbyqxmd.com/read/28344913/indoor-localisation-through-object-detection-within-multiple-environments-utilising-a-single-wearable-camera
#9
Colin Shewell, Chris Nugent, Mark Donnelly, Haiying Wang, Macarena Espinilla
The recent growth in the wearable sensor market has stimulated new opportunities within the domain of Ambient Assisted Living, providing unique methods of collecting occupant information. This approach leverages contemporary wearable technology, Google Glass, to facilitate a unique first-person view of the occupants immediate environment. Machine vision techniques are employed to determine an occupant's location via environmental object detection. This method provides additional secondary benefits such as first person tracking within the environment and lack of required sensor interaction to determine occupant location...
2017: Health and Technology
https://www.readbyqxmd.com/read/28344016/grp78-enabled-micelle-based-glioma-targeted-drug-delivery
#10
Danni Ran, Jiani Mao, Qing Shen, Cao Xie, Changyou Zhan, Ruifeng Wang, Weiyue Lu
GRP78, a specific cancer cell-surface marker, is implicated in cancer cells proliferation, apoptosis resistance, metastasis and drug resistance. l-VAP (SNTRVAP) is a tumor homing peptide exhibiting high binding affinity in vitro to GRP78 protein overexpressed on glioma, glioma stem cells, vasculogenic mimicry and neovasculature. Even though short peptides are often non-immunogenic and demonstrate high affinity to tumor cells, their targeting efficacy is always undermined by rapid blood clearance and enzymatic degradation...
March 23, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/28342743/measurement-of-ion-fluxes-across-epithelia
#11
REVIEW
Miroslaw Zajac, Krzysztof Dolowy
Epithelial tissues line all wet surfaces of vertebrate bodies. Their major function is directional transport of ions and water. Cells forming an epithelial layer are bound together by a tight junction that forms a barrier to ion flux. Ions and water are transported via specialized molecules. The presence of a defect in a single ion channel molecule leads to cystic fibrosis - the most common, fatal, human genetic disease. The paper describes ion transport data obtained by means of different experimental techniques...
March 22, 2017: Progress in Biophysics and Molecular Biology
https://www.readbyqxmd.com/read/28342296/control-of-osmotic-pressure-to-improve-cell-viability-in-cell-laden-tissue-engineering-constructs
#12
A F Carvalho, L Gasperini, R S Ribeiro, A P Marques, R L Reis
Design of tissue engineering strategies deals with the need to balance both biomaterials characteristics and techniques specificities, often resulting in cell-compromising processing conditions. One important factor often disregarded is the osmotic pressure to which cells are exposed to. An in-house microfluidic system was used to prove that addition of an osmotic regulator significantly benefits the generation of viable cell-laden hydrogels under harsh processing conditions. Human adipose-derived stem cells (hASCs) were resuspended in 1...
March 25, 2017: Journal of Tissue Engineering and Regenerative Medicine
https://www.readbyqxmd.com/read/28341556/advanced-electron-holography-techniques-for-in-situ-observation-of-solid-state-lithium-ion-conductors
#13
Tsukasa Hirayama, Yuka Aizawa, Kazuo Yamamoto, Takeshi Sato, Hidekazu Murata, Ryuji Yoshida, Craig A J Fisher, Takehisa Kato, Yasutoshi Iriyama
Advanced techniques for overcoming problems encountered during in situ electron holography experiments in which a voltage is applied to an ionic conductor are reported. The three major problems encountered were 1) electric-field leakage from the specimen and its effect on phase images, 2) high electron conductivity of damage layers formed by the focused ion beam method, and 3) chemical reaction of the specimen with air. The first problem was overcome by comparing experimental phase distributions with simulated images in which three-dimensional leakage fields were taken into account, the second by removing the damage layers using a low-energy narrow Ar ion beam, and the third by developing an air-tight biasing specimen holder...
March 15, 2017: Ultramicroscopy
https://www.readbyqxmd.com/read/28341312/evaluation-of-methods-for-the-assessment-of-attention-while-driving
#14
Katja Kircher, Christer Ahlstrom
The ability to assess the current attentional state of the driver is important for many aspects of driving, not least in the field of partial automation for transfer of control between vehicle and driver. Knowledge about the driver's attentional state is also necessary for the assessment of the effects of additional tasks on attention. The objective of this paper is to evaluate different methods that can be used to assess attention, first theoretically, and then empirically in a controlled field study and in the laboratory...
March 21, 2017: Accident; Analysis and Prevention
https://www.readbyqxmd.com/read/28341290/the-cessation-of-breathing-in-the-chicken-embryo-during-cold-hypometabolism
#15
Ryoji Ide, Satoko Tomita Ide, Jacopo P Mortola
The avian embryo toward end-incubation combines gas exchange through the chorioallantoic membrane (CAM) and pulmonary ventilation (V˙E). The main experiments examined breathing activity during cold-hypometabolism. Chicken embryos close to hatching were prepared for simultaneous measurements of oxygen consumption ( [Formula: see text] ) and carbon dioxide production ( [Formula: see text] ; open-flow methodology) and breathing frequency (f; barometric technique). As ambient (Ta) and egg temperature (Tegg) dropped, breathing eventually ceased at ∼18°C, when [Formula: see text] and [Formula: see text] were 22-28% of the normothermic values...
March 21, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28341132/stochastic-modeling-and-numerical-simulation-of-gene-regulatory-networks-with-protein-bursting
#16
Manuel Pájaro, Antonio A Alonso, Irene Otero-Muras, C Vázquez
Gene expression is inherently stochastic. Advanced single-cell microscopy techniques together with mathematical models for single gene expression led to important insights in elucidating the sources of intrinsic noise in prokaryotic and eukaryotic cells. In addition to the finite size effects due to low copy numbers, translational bursting is a dominant source of stochasticity in cell scenarios involving few short lived mRNA transcripts with high translational efficiency (as is typically the case for prokaryotes), causing protein synthesis to occur in random bursts...
March 21, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28340784/separation-of-20-coumarin-derivatives-using-the-capillary-electrophoresis-method-optimized-by-a-series-of-doehlert-experimental-designs
#17
Michał Woźniakiewicz, Marta Gładysz, Paweł M Nowak, Justyna Kędzior, Paweł Kościelniak
The aim of this study was to develop the first CE-based method enabling separation of 20 structurally similar coumarin derivatives. To facilitate method optimization a series of three consequent Doehlert experimental designs with the response surface methodology was employed, using number of peaks and the adjusted time of analysis as the selected responses. Initially, three variables were examined: buffer pH, ionic strength and temperature (No. 1 Doehlert design). The optimal conditions provided only partial separation, on that account, several buffer additives were examined at the next step: organic cosolvents and cyclodextrin (No...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28340768/sio2-coated-magnetic-graphene-oxide-modified-with-polypyrrole-polythiophene-a-novel-and-efficient-nanocomposite-for-solid-phase-extraction-of-trace-amounts-of-heavy-metals
#18
Karam Molaei, Hasan Bagheri, Ali Akbar Asgharinezhad, Homeira Ebrahimzadeh, Mojtaba Shamsipur
The synthesis of a novel nanocomposite comprised of SiO2-coated magnetic graphene oxide modified with a pyrrole-thiophene (mGO/SiO2@coPPy-Th) copolymer is reported in the present work. The nanocomposite was applied for the fast magnetic solid phase extraction (MSPE) of trace levels of copper, lead, chromium, zinc and cadmium from water and agricultural samples. The nanocomposite was prepared in three steps: (1) decoration of graphene oxide sheets with magnetite nanoparticles thorough a facile one-step chemical reaction strategy; (2) chemical grafting by a silica layer to obtain high stability in acidic solutions; and (3) surface modification by coPPy-Th via simultaneous oxidation polymerization of pyrrole and thiophene in the presence of mGO/SiO2 composite...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28340762/reference-free-spectroscopic-determination-of-fat-and-protein-in-milk-in-the-visible-and-near-infrared-region-below-1000nm-using-spatially-resolved-diffuse-reflectance-fiber-probe
#19
Andrey Bogomolov, Valeria Belikova, Vladislav Galyanin, Anastasiia Melenteva, Hans Meyer
New technique of diffuse reflectance spectroscopic analysis of milk fat and total protein content in the visible (Vis) and adjacent near infrared (NIR) region (400-995nm) has been developed and tested. Sample analysis was performed through a probe having eight 200-µm fiber channels forming a linear array. One of the end fibers was used for the illumination and other seven - for the spectroscopic detection of diffusely reflected light. One of the detection channels was used as a reference to normalize the spectra and to convert them into absorbance-equivalent units...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28340702/selective-solid-phase-extraction-of-jwh-synthetic-cannabinoids-by-using-computationally-designed-peptides
#20
Marcello Mascini, Camilla Montesano, German Perez, Joseph Wang, Dario Compagnone, Manuel Sergi
The objective of the present work is to demonstrate a rational way to prepare selective sorbents able to extract simultaneously several structural analogs. For this purpose the binding specificity of two hexapeptides computationally designed (VYWLVW and YYIGGF) versus four synthetic cannabinoids Naphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH 018), naphthalen-1-yl-(1-butylindol-3-yl)methanone (JWH 073), (R)-(1-((1-methylpiperidin-2-yl)methyl)-1H-indol-3-yl)(naphthalen-1-yl)methanone (AM 1220) and (R)-(+)-[2,3-Dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-napthalenylmethanone (WIN 55) was computationally studied and then experimentally tested by solid-phase extraction (SPE) clean-up and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis...
May 15, 2017: Talanta
keyword
keyword
20110
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"