349 research outputs found
TREE CROWN DELINEATION ON VHR AERIAL IMAGERY WITH SVM CLASSIFICATION TECHNIQUE OPTIMIZED BY TAGUCHI METHOD: A CASE STUDY IN ZAGROS WOODLANDS
The Support Vector Machine (SVM) is a theoretically superior machine learning methodology with great results in classification of
remotely sensed datasets. Determination of optimal parameters applied in SVM is still vague to some scientists. In this research, it is
suggested to use the Taguchi method to optimize these parameters. The objective of this study was to detect tree crowns on very high
resolution (VHR) aerial imagery in Zagros woodlands by SVM optimized by Taguchi method. A 30 ha plot of Persian oak (Quercus
persica) coppice trees was selected in Zagros woodlands, Iran. The VHR aerial imagery of the plot with 0.06 m spatial resolution
was obtained from National Geographic Organization (NGO), Iran, to extract the crowns of Persian oak trees in this study. The SVM
parameters were optimized by Taguchi method and thereafter, the imagery was classified by the SVM with optimal parameters. The
results showed that the Taguchi method is a very useful approach to optimize the combination of parameters of SVM. It was also
concluded that the SVM method could detect the tree crowns with a KHAT coefficient of 0.961 which showed a great agreement
with the observed samples and overall accuracy of 97.7% that showed the accuracy of the final map. Finally, the authors suggest
applying this method to optimize the parameters of classification techniques like SVM
Thermal inactivation and conformational lock studies on glucose oxidase
In this study, the dissociative thermal inactivation
and conformational lock theories are applied for the
homodimeric enzyme glucose oxidase (GOD) in order to
analyze its structure. For this purpose, the rate of activity
reduction of glucose oxidase is studied at various temperatures
using b-D-glucose as the substrate by incubation of
enzyme at various temperatures in the wide range between
40 and 70 ļæ½C using UVāVis spectrophotometry. It was
observed that in the two ranges of temperatures, the
enzyme has two different forms. In relatively low temperatures,
the enzyme is in its dimeric state and has normal
activity. In high temperatures, the activity almost disappears
and it aggregates. The above achievements are confirmed
by dynamic light scattering. The experimental
parameter āānāā as the obvious number of conformational
locks at the dimer interface of glucose oxidase is obtained
by kinetic data, and the value is near to two. To confirm the
above results, the X-ray crystallography structure of the
enzyme, GOD (pdb, 1gal), was also studied. The secondary
and tertiary structures of the enzyme to track the thermal
inactivation were studied by circular dichroism and
fluorescence spectroscopy, respectively. We proposed a
mechanism model for thermal inactivation of GOD based
on the absence of the monomeric form of the enzyme by
circular dichroism and fluorescence spectroscopy
Nano-Fe3O4/O2: Green, Magnetic and Reusable Catalytic System for the Synthesis of Benzimidazoles
Magnetic nano-Fe3O4 was applied in the presence of atmospheric air as a green, efficient, heterogeneous and reusable catalyticĀ system for the synthesis of benzimidazoles via the reactions of o-phenylenediamine (1 eq) with aryl aldehydes (1 eq) in excellentyields (85ā97 %) and short reaction times (30ā100 min) with a proposed mechanism.Keywords:Ā Benzimidazole, benzene-1,2-diamine, aldehyde, nano-Fe3O4, heterogeneous catalyst, magnetite, O
Atorvastatin treatment softens human red blood cells: An optical tweezers study
Optical tweezers are proven indispensable single-cell micro-manipulation and mechanical phenotyping tools. In this study, we have used optical tweezers for measuring the viscoelastic properties of human red blood cells (RBCs). Comparison of the viscoelastic features of the healthy fresh and atorvastatin treated cells revealed that the drug softens the cells. Using a simple modeling approach, we proposed a molecular model that explains the drug-induced softening of the RBC membrane. Our results suggest that direct interactions between the drug and cytoskeletal components underlie the drug-induced softening of the cells. ĆĀ© 2018 Optical Society of America
Sulfonic acid functionalized imidazolium salts/ FeCl3 as novel and highly efficient catalytic systems for the synthesis of benzimidazoles at room temperature
AbstractIonic liquid 3-methyl-1-sulfonic acid imidazolium chloride/ FeCl3, as well as ionic liquid 1, 3-disulfonic acid imidazolium chloride/ FeCl3 catalytic systems, efficiently catalyzes the condensation of benzene-1, 2-diamine with aromatic aldehydes in the presence of atmospheric air as a green oxidant in ethyl acetate at room temperature to afford benzimidazole derivatives in high yields and in short reaction times. The reaction is also efficiently performed when carboxylic acids are used instead of aldehydes
Nutritional value of raw soybeans, extruded soybeans, roasted soybeans and tallow as fat sources in early lactating dairy cows
Thirty multiparous Holstein cows (29.8 Ā± 4.01days in milk; 671.6 Ā± 31.47 kg of body weight) were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets with either tallow, raw soybean, extruded soybean, or roasted soybean added to provide 1.93% supplemental fat. Dry matter and NEL intakes were similar among treatments, while cows fed fat diets had significantly (P<0.05) high NEL intakes when compared to control with no fat. Supplemental fat, whether tallow or full fat soybeans increased milk production (1.89-2.45 kg/d; P<0.01) and FCM production (1.05-2.79; P<0.01). Milk fat yield and percentage of cows fed fat-supplemented diets were significantly (P<0.01 and P<0.05 respectively) higher than control. Between fat-supplemented diets, roasted soybean caused highest milk fat yield and extruded soybean caused lowest milk fat yield. There was no significant effect of supplemental fat on the milk protein and lactose content and yield. Feed efficiency of fat-supplemented diets was significantly (P<0.01) higher than control. Body weight, body weight change and BCS (body condition score) of cows, as well as energy balance and energy efficiency were similar between treatments. In conclusion, while there was no significant effect of fat sources on production response of cows, fat originating from heat-treated soybean help to minimize imported RUP (rumen undegradable protein) sources level as fish meal in comparison with tallow and raw soybean oil. In the Current study, there was no statistical significance among nutritional values of oil from extruded soybeans and roasted soybeans
Thermal Unfolding Pathway of PHD2 Catalytic Domain in Three Different PHD2 Species: Computational Approaches
Prolyl hydroxylase domain 2 containing protein (PHD2) is a key protein in regulation of angiogenesis and metastasis. In normoxic condition, PHD2 triggers the degradation of hypoxia-inducible factor 1 (HIF-1Ī±) that induces the expression of hypoxia response genes. Therefore the correct function of PHD2 would inhibit angiogenesis and consequent metastasis of tumor cells in normoxic condition. PHD2 mutations were reported in some common cancers. However, high levels of HIF-1Ī± protein were observed even in normoxic metastatic tumors with normal expression of wild type PHD2. PHD2 malfunctions due to protein misfolding may be the underlying reason of metastasis and invasion in such cases. In this study, we scrutinize the unfolding pathways of the PHD2 catalytic domainās possible species and demonstrate the properties of their unfolding states by computational approaches. Our study introduces the possibility of aggregation disaster for the prominent species of PHD2 during its partial unfolding. This may justify PHD2 inability to regulate HIF-1Ī± level in some normoxic tumor types
Atorvastatin treatment softens human red blood cells: An optical tweezers study
Optical tweezers are proven indispensable single-cell micro-manipulation and mechanical phenotyping tools. In this study, we have used optical tweezers for measuring the viscoelastic properties of human red blood cells (RBCs). Comparison of the viscoelastic features of the healthy fresh and atorvastatin treated cells revealed that the drug softens the cells. Using a simple modeling approach, we proposed a molecular model that explains the drug-induced softening of the RBC membrane. Our results suggest that direct interactions between the drug and cytoskeletal components underlie the drug-induced softening of the cells. ĆĀ© 2018 Optical Society of America
Rapid prototyping of soft bioelectronic implants for use as neuromuscular interfaces
Neuromuscular interfaces are required to translate bioelectronic technologies for application in clinical medicine. Here, by leveraging the robotically controlled ink-jet deposition of low-viscosity conductive inks, extrusion of insulating silicone pastes and in situ activation of electrode surfaces via cold-air plasma, we show that soft biocompatible materials can be rapidly printed for the on-demand prototyping of customized electrode arrays well adjusted to specific anatomical environments, functions and experimental models. We also show, with the monitoring and activation of neuronal pathways in the brain, spinal cord and neuromuscular system of cats, rats and zebrafish, that the printed bioelectronic interfaces allow for long-term integration and functional stability. This technology might enable personalized bioelectronics for neuroprosthetic applications
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