31 research outputs found
Discrimination of filled and unfilled grains of rice panicles using thermal and RGB images
In recent days, the agricultural research community is focusing on the development of different varieties of aerobic rice, as it consumes less water for its growth. In general, the yield of a crop is considered as a critical performance metric to evaluate different varieties of rice. The count of filled grains in panicles provides a measure for the yield of a crop. The evaluation of yield is a laborious, tedious process and requires human intervention. Hence, this study aims to automate the process for differentiating filled and unfilled grains of rice across different genotypes/varieties and also to help agricultural scientists in the rapid evaluation of different varieties. More precisely, this paper proposes two novel methods that involve RGB and thermal images: (a) Discrimination based on RGB Images (DRI) (b) Discrimination based on Thermal Images (DTI). The study of proposed methods on 15 rice-panicles of different genotypes indicates that DRI method, which involves colour of grains, is found to be challenging to discriminate between filled and unfilled grains. Whereas, DTI method, which makes use of thermal images in differentiating filled and unfilled grains, is found to be profoundly convenient. The performance analysis demonstrates that the proposed DTI method, with averaged absolute errors (AAEs) in discriminating filled grains (2.66%) and unfilled grains (11.389%), outperforms the proposed DRI method with an AAEs in discriminating filled grains (10.664%) and unfilled grains (34.296%). The present investigation resulted in the development of DTI method to discriminate against the filled and unfilled grains across genotypes, and it can be used in rice improvement programs in the future
Influence of 1α, 25-dihydroxyvitamin D3 [1, 25(OH)2D3] on the expression of Sox 9 and the transient receptor potential vanilloid 5/6 ion channels in equine articular chondrocytes
Background
Sox 9 is a major marker of chondrocyte differentiation. When chondrocytes are cultured in vitro they progressively de-differentiate and this is associated with a decline in Sox 9 expression. The active form of vitamin D, 1, 25 (OH)2D3 has been shown to be protective of cartilage in both humans and animals. In this study equine articular chondrocytes were grown in culture and the effects of 1, 25 (OH)2D3 upon Sox 9 expression examined. The expression of the transient receptor potential vanilloid (TRPV) ion channels 5 and 6 in equine chondrocytes in vitro, we have previously shown, is inversely correlated with de-differentiation. The expression of these channels in response to 1, 25 (OH)2D3 administration was therefore also examined.
Results
The active form of vitamin D (1, 25 (OH)2D3) when administered to cultured equine chondrocytes at two different concentrations significantly increased the expression of Sox 9 at both. In contrast 1, 25 (OH)2D3 had no significant effect upon the expression of either TRPV 5 or 6 at either the protein or the mRNA level.
Conclusions
The increased expression of Sox 9, in equine articular chondrocytes in vitro, in response to the active form of vitamin D suggests that this compound could be utilized to inhibit the progressive de-differentiation that is normally observed in these cells. It is also supportive of previous studies indicating that 1α, 25-dihydroxyvitamin D3 can have a protective effect upon cartilage in animals in vivo. The previously observed correlation between the degree of differentiation and the expression levels of TRPV 5/6 had suggested that these ion channels may have a direct involvement in, or be modulated by, the differentiation process in vitro. The data in the present study do not support this
Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites
The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions.
The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness
of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence
were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density
and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that
the wood in the starch composites did not prevent water loss from the samples.Peer reviewe
A microfluidic approach for hemoglobin detection in whole blood
Diagnosis of anemia relies on the detection of hemoglobin levels in a blood sample.
Conventional blood analyzers are not readily available in most low-resource regions where
anemia is prevalent, so detection methods that are low-cost and point-of-care are needed.
Here, we present a microfluidic approach to measure hemoglobin concentration in a sample
of whole blood. Unlike conventional approaches, our microfluidic approach does not require
hemolysis. We detect the level of hemoglobin in a blood sample optically by illuminating
the blood in a microfluidic channel at a peak wavelength of 540 nm and measuring its
absorbance using a CMOS sensor coupled with a lens to magnify the image onto the detector.
We compare measurements in microchannels with channel heights of 50 and 115 μm and found
the channel with the 50 μm height provided a better range of detection. Since we use whole
blood and not lysed blood, we fit our data to an absorption model that includes optical
scattering in order to obtain a calibration curve for our system. Based on this
calibration curve and data collected, we can measure hemoglobin concentration within 1
g/dL for severe cases of anemia. In addition, we measured optical density for blood
flowing at a shear rate of 500 s-1 and observed it did not affect the nonlinear
model. With this method, we provide an approach that uses microfluidic detection of
hemoglobin levels that can be integrated with other microfluidic approaches for blood
analysis
CIG based Stress Identification Method for Maize Crop using UAV based Remote Sensing
The health and yield of crops depend on the use of water, nutrients, and fertilizers. Due to climatic changes and reduction in rainfall, farmers are relying on groundwater for irrigation, which should be used optimally. The use of water and other agronomic inputs can be optimized by monitoring the health of crops and soil. Usually, it is done by manual observation, which is labor-intensive and time-consuming. In this paper, we propose Chlorophyll Index Green (CIG) vegetative index-based method for monitoring the crop health using near-infrared, green, and red band images acquired using a multispectral camera mounted on Unmanned Ariel Vehicle (UAV). The proposed method clearly classifies the water-stressed area of the field and helps in optimizing the irrigation process and monitoring the crop-health
The Giardia ventrolateral flange is a lamellar membrane protrusion that supports attachment.
Attachment to the intestinal epithelium is critical to the lifestyle of the ubiquitous parasite Giardia lamblia. The ventrolateral flange is a sheet-like membrane protrusion at the interface between parasites and attached surfaces. This structure has been implicated in attachment, but its role has been poorly defined. Here, we identified a novel actin associated protein with putative WH2-like actin binding domains we named Flangin. Flangin complexes with Giardia actin (GlActin) and is enriched in the ventrolateral flange making it a valuable marker for studying the flanges' role in Giardia biology. Live imaging revealed that the flange grows to around 1 μm in width after cytokinesis, then remains uniform in size during interphase, grows in mitosis, and is resorbed during cytokinesis. A flangin truncation mutant stabilizes the flange and blocks cytokinesis, indicating that flange disassembly is necessary for rapid myosin-independent cytokinesis in Giardia. Rho family GTPases are important regulators of membrane protrusions and GlRac, the sole Rho family GTPase in Giardia, was localized to the flange. Knockdown of Flangin, GlActin, and GlRac result in flange formation defects. This indicates a conserved role for GlRac and GlActin in forming membrane protrusions, despite the absence of canonical actin binding proteins that link Rho GTPase signaling to lamellipodia formation. Flangin-depleted parasites had reduced surface contact and when challenged with fluid shear force in flow chambers they had a reduced ability to remain attached, confirming a role for the flange in attachment. This secondary attachment mechanism complements the microtubule based adhesive ventral disc, a feature that may be particularly important during mitosis when the parental ventral disc disassembles in preparation for cytokinesis. This work supports the emerging view that Giardia's unconventional actin cytoskeleton has an important role in supporting parasite attachment