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41.
In coral mariculture, growth is one of the most common ways to track success. However, numerous methods of monitoring coral growth make comparative studies challenging. A literature review of 39 studies from 1982 to 2017 indicated that the most predominant non‐invasive methods used were linear and areal measurement and these were evaluated for their accuracy using nursery‐reared corals. The monthly change in linear and areal growth rates of six coral species (= 215), Pocillopora acuta, Hydnophora rigida, Merulina ampliata, Podabacia crustacea, Echinopora lamellosa and Platygyra sinensis were measured via photogrammetry. We tested whether the planar area of coral colonies can be estimated using three geometric formulas of linear measurements. Based on the literature review, the six types of measurement methods were namely linear, volume, weight, area, count of polyps/branches and calcification, in decreasing order of application. Our results showed that the change in area calculated by geometric mean diameter (GMD) formulas provided the most accurate estimation among the three formulas and was strongly correlated with planar area (R2 ≥ .60; p < .05) for all coral species, except E. lamellosa and Pl. sinensis. However, our findings suggest that it is not ideal to use geometric formulas to estimate the change in area. Instead, we posit that areal photogrammetry represents the simplest yet accurate non‐invasive method for rapid monitoring of extensive areas of corals in situ. Lastly, we discuss the recommendations and limitations for areal photogrammetry.  相似文献   
42.
MytiLec; a novel lectin isolated from the Mediterranean mussel (Mytilus galloprovincialis); shows strong binding affinity to globotriose (Gb3: Galα1-4Galβ1-4Glc). MytiLec revealed β-trefoil folding as also found in the ricin B-subunit type (R-type) lectin family, although the amino acid sequences were quite different. Classification of R-type lectin family members therefore needs to be based on conformation as well as on primary structure. MytiLec specifically killed Burkitt''s lymphoma Ramos cells, which express Gb3. Fluorescein-labeling assay revealed that MytiLec was incorporated inside the cells. MytiLec treatment of Ramos cells resulted in activation of both classical MAPK/ extracellular signal-regulated kinase and extracellular signal-regulated kinase (MEK-ERK) and stress-activated (p38 kinase and JNK) Mitogen-activated protein kinases (MAPK) pathways. In the cells, MytiLec treatment triggered expression of tumor necrosis factor (TNF)-α (a ligand of death receptor-dependent apoptosis) and activation of mitochondria-controlling caspase-9 (initiator caspase) and caspase-3 (activator caspase). Experiments using the specific MEK inhibitor U0126 showed that MytiLec-induced phosphorylation of the MEK-ERK pathway up-regulated expression of the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest and TNF-α production. Activation of caspase-3 by MytiLec appeared to be regulated by multiple different pathways. Our findings, taken together, indicate that the novel R-type lectin MytiLec initiates programmed cell death of Burkitt’s lymphoma cells through multiple pathways (MAPK cascade, death receptor signaling; caspase activation) based on interaction of the lectin with Gb3-containing glycosphingolipid-enriched microdomains on the cell surface.  相似文献   
43.
Wu  Haiyun  Ogata  Madoka  Ohnuki  Hitoshi  Endo  Hideaki 《Fisheries Science》2021,87(1):151-159
Fisheries Science - To elucidate the dynamics of oxidative stress in fish, it is necessary to know the concentration of superoxide anions as a precursor to various reactive oxygen species in the...  相似文献   
44.
Fungicide resistance in plant pathogens is often caused by a single point mutation in a gene encoding fungicide target proteins. Such is the case for resistance to MBI-D (inhibitors of scytalone dehydratase in melanin biosynthesis) fungicides in rice blast fungus (Magnaporthe oryzae), which is caused by a mutation in the scytalone dehydratase gene that results in a replacement of valine with methionine at codon 75 of the fungicide target protein. PCR-Luminex, a novel system developed for high-throughput analysis of single nucleotide polymorphisms (SNPs) was successfully introduced to diagnose MBI-D resistance using specific oligonucleotide probes coupled with fluorescent beads. The PCR-Luminex system was further tested for its potential in identifying species causing Fusarium head blight on wheat. Four major pathogens, Fusarium graminearum (=F. asiaticum), F. culmorum, F. avenaceum, and Microdochium nivale, known to cause the disease, were tested, and the species were identified using the PCR-Luminex method. So far, this report is the first on the application of the DNA-based PCR-Luminex system in the area of crop protection and/or agricultural sciences.  相似文献   
45.
Identifying the Fusarium species cause Fusarium head blight (FHB) and produces mycotoxins in wheat and other cereal is difficult and time consuming because of confusing phenotypic classification systems. In Japan, the F. graminearum complex, F. culmorum, F. avenaceum, and Microdochium nivale predominantly cause FHB. The internal transcribed spacer (ITS) and 5.8S of rDNA, a partial sequence of β-tubulin and mitochondrial cytochrome b (cytb) genes of the four species were PCR-amplified and analyzed. On the basis of the ITS, β-tubulin and cytb sequences, F. avenaceum and M. nivale are distinct from the F. graminearum complex and F. culmorum, whereas the F. graminearum complex is closely related to F. culmorum. Moreover, thiophanate–methyl-resistant isolates of the F. graminearum complex and F. culmorum did not have an amino acid substitution at amino acid codon 198 or 200 of β-tubulin. In contrast, very highly or highly thiophanate–methyl-resistant isolates of M. nivale had Glu (GAG) substituted with Ala (GCG) or Lys (AAG) at codon 198, respectively. The allele-specific PCR assay was used to identify the F. graminearum complex and F. culmorum, and these Fusarium species could be distinguished rapidly.  相似文献   
46.
A label-free immunosensor for detecting the oocyte maturation-inducing hormone 17, 20β-dihydroxy-4-pregnen-3-one (DHP), was developed. A principle of the sensor system was based on differences in electrochemical activity changed by an immunoreaction in the absence and presence of DHP. For preparation of the immunosensor, anti-DHP IgG was immobilized on an Au working electrode modified with a self-assembled monolayer of 3-mercaptopropionic acid. The sensor was immersed into a sample solution containing DHP. DHP was determined by cyclic voltammetry. The immunosensor showed a specific response to DHP, and the oxidation peak current linearly decreased in the range of 7.8–500 pg ml−1 with a correlation coefficient of 0.996. The sensor system was applied to determine the DHP levels in plasma of goldfish and was compared with the DHP levels of the same samples determined using an ELISA as the conventional method. Good correlation was obtained between values determined using both methods in the range of 0.1–7.7 ng ml−1 (correlation coefficient 0.876). These findings suggest that the proposed label-free immunosensor can be used to analyze DHP levels in fish plasma samples.  相似文献   
47.
We developed a wireless monitoring system to monitor fish condition by tracking the change in whole cholesterol concentration. The whole cholesterol concentration of fish is a source of steroid hormones or indicator of immunity level, which makes its detection important for tracking physiological condition of fish. Wireless monitoring system comprises of mediator-type biosensor and wireless transmission device. Biosensor is implantable to fish body, and transmission device is so light, in that fish is allowed to swim freely during monitoring. Cholesterol esterase and oxidase were fixated on to the detection site of biosensor and used to detect the whole cholesterol concentration. However, cholesterol oxidase incorporates oxidation–reduction reaction of oxygen for detection, which concentration fluctuates easily due to change in environmental condition. Meanwhile, mediator-type biosensor enables monitoring of whole cholesterol concentration by using mediator to substitute that oxidation–reduction reaction of oxygen. Characteristic of fabricated mediator-type biosensor was tested. The sensor output current of mediator-type biosensor remained stable compared to output current of non-mediator-type biosensor under fluctuating oxygen concentration of 0–8 ppm, which implied that this sensor is less affected by change in dissolved oxygen concentration. That biosensor was then implanted into fish for wireless monitoring. As a result, approximately 48 h of real-time monitoring was successful.  相似文献   
48.
Boards were produced by using SP adhesive, which contains styrene-butadiene rubber and polyethylene glycol as major constituents. The use of polyethylene in place of clay, which is also a generally used constituent of SP adhesive, was confirmed to improve board properties. In general, the properties of boards are poorer when produced by two-stage pressing, in which mats are first processed by temporary adhesion and then processed into boards by permanent adhesion; however, the properties of boards produced by two-stage pressing were improved when polyethylene was added to the SP adhesive. In addition, internal bond strength and thickness swelling was greatly improved when boards were produced from ozonized wood and by sealed pressing. Thus, the properties impaired by two-stage pressing were improved by ozonization and sealed pressing.  相似文献   
49.
50.
Abstract

Properties of sesquioxides, clay mineralogical composition, and charge characteristics of Brown Forest soils developed under beech forests in the Kinki (Ohdaigahara) and the Tohoku District (Hakkoda) were studied with special reference to their pedogenetic processes.

The Brown Forest soils in the Kinki District were characterized by the translocation of free Al, formation of Al and/or Fe-humus complexes throughout the profile, and the predominance of 2:1: 1-2:1 intergrade minerals in the subsurface horizons, whereas those in the Tohoku District were characterized by the formation of allophane and no remarkable translocation of free Al oxides. This difference in the pedogenetic processes under the same vegetation was reflected on the amounts of Al released from primary minerals in relation to the amounts of organic matter accumulated. Major distinctive characteristics included the values of the Alp/Alo, the Fep/Feo, the Alo/Ald ratios, the Sio content, and the STPT-ZPC and pH(H2O) values.

Among these the values of the Alo/Ald ratio and/or the Sio content were found to be suitable indices for the differentiation of Brown Forest soils from Andisols in Japan In addition to the criteria used to define andic soil properties.  相似文献   
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