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2022 ◽  
Vol 8 ◽  
Author(s):  
Shixiong Dong ◽  
Shijun Xu ◽  
Jian Zhang ◽  
Riaz Hussain ◽  
Hong Lu ◽  
...  

The bar-headed goose (Anser indicus) has two black spots on its head. It is considered an important bird in China. It breeds in plateau lakes, especially saltwater lakes, and swamp areas. However, the intestinal flora of wild bar-headed geese in the Tibet Autonomous Region is currently not known. In this study, 16S rDNA sequencing was performed on the intestinal microbes of wild bar-headed geese. A total of 513,505 reads of raw data were obtained, and the results analyzed the average number of 128,376 ± 2,392 reads per sample. The microbiota of all samples consists of 10 main bacterial phyla, including Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, Cyanobacteria, Patescibacteria, Deferribacteres, Planctomy-cetes, Fusobacteria, and Tenericutes. The results indicated that Firmicutes (67.34%) was the predominant phylum, followed by Proteobacteria (29.03%) and Cyanobacteria (1.97%). In our research, we identified the intestinal flora of the wild bar-headed goose, which provides valuable information for further research on the gene function of the bar-headed goose and the intestinal flora of wild animals. These findings are also useful and valuable for genetic and high-altitude research in the Tibet Autonomous Region.


Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 51
Author(s):  
Takahiro Shuto ◽  
Yuichi Mine ◽  
Seicho Makihira ◽  
Hiroki Nikawa ◽  
Takanori Wachi ◽  
...  

Fluoride and abrasives in toothpastes may cause corrosion and deterioration of the titanium used for implants and other prostheses. The purpose of this study was to investigate how the presence or absence and types of fluoride and abrasives affected the titanium surface texture. Brushing with toothpastes was performed on pure-titanium discs using an abrasive testing machine. Unprocessed titanium discs without brushing were used as control samples. Surface roughness, color, and gloss of titanium were measured and the differences compared with the control were analyzed. Additionally, titanium surfaces and abrasives in toothpastes were observed using a scanning electron microscope to compare the surface texture of each sample. Some toothpastes (abrasive+) significantly increased the difference in surface roughness, color, and gloss, compared with ultrapure water. Toothpaste (fluoride+/abrasive+) that had many polygonal abrasive particles led to the largest color differences and exhibited notable scratches and a larger number of contaminant- or corrosion-like black spots. In contrast, brushing with toothpaste without fluoride or abrasives (fluoride−/abrasive−) caused little change to the titanium surface. These results suggest that both fluoride and abrasives in toothpaste used for brushing may be factors that affect surface texture and corrosion resistance of titanium.


Minerals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1434
Author(s):  
Jiaxin Wang ◽  
Guanghai Shi

Green nephrites are widely pursued for their mild texture and vivid color. In recent years, many Russian green nephrites appeared in China (the world’s largest nephrite market) and competed with the Chinese Manas green nephrites, which are traditionally highly valued. In this study, we compared the appearance, mineralogy and geochemical features (with EPMA and LA-ICP-MS) of Chinese (Manas) and Russian (East Sayan) green nephrites to objectively characterize and distinguish between these two nephrites. Chinese (Manas) and Russian (East Sayan) green nephrites are mined from serpentinized ultramafic units in the northern Tian Shan and East Sayan orogen, respectively. In terms of appearance, the Manas green nephrites are slightly bluish or grayish, whilst their East Sayan counterparts are brighter (duck-egg cyan). The Manas nephrites commonly have a caramel color, crumple structure, characteristic white globules and sinuous veins, green stains and yellow–green veins, together with a local fibrous structure. The East Sayan green nephrites are more transparent, with a gentler fine texture, uniform color, many black spots and a few green spots. Some green nephrites from the Arahushun mine of East Sayan have an ice-like appearance. Microscopic petrography and EPMA analysis indicate that both the Manas and East Sayan green nephrites comprise mainly tremolite with minor actinolite. Minor minerals in the Manas samples include chromite, chlorite-group minerals, and uvarovite; whilst those in the East Sayan samples include actinolite, chromite, chlorite-group minerals, and bornite. Bornite is not found in any other sources of green nephrite, and thus is characteristic of Russian (East Sayan) green nephrites. LA-ICP-MS trace element data in their amphiboles and Single-Factor Analysis of Variance (ANOVA) results suggest that the differences in Cr, Zn, Y, Ba, and Sr contents and values of δEu, Eu/Sm, (La/Yb)N, (La/Sm)N, (Gd/Yb)N, ∑HREE, ∑LREE/∑HREE between the two nephrites are present, and can be used as their origin trace.


Agriculture ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1264
Author(s):  
Urszula Wachowska ◽  
Edyta Kwiatkowska ◽  
Wioletta Pluskota

Background: Sida hermaphrodita (Virginia fanpetals) was introduced to Poland nearly 70 years ago as a potential fodder plant, and it is gaining importance as an energy crop. Alternaria alternata transmitted by seeds may exert a negative effect on the health of Virginia fanpetals plants. Methods: The virulence of the A. alternata pathogen, isolated from Virginia fanpetals seeds, was tested on detached leaves of Virginia fanpetals plants. The isolates were identified as A. alternata based on partial sequence analysis of Alta1, TEF1a and gdp genes and the ITS 1–5.8SrDNA–ITS 2 region. Pathogen transmission from seeds to seedlings and the influence of seed dressing with a suspension of Aureobasidium pullulans on seedling health were analyzed in a greenhouse experiment. Results: Three of the nine analyzed A. alternata isolates were highly pathogenic for S. hermaphrodita. The initial symptoms of leaf infection were small, round dark brown or black spots which grew into larger dark brown spots surrounded by a chlorotic halo. Alternaria alternata was re-isolated from inoculated plants and was identified as the causal agent of Alternaria leaf spot disease. In the greenhouse experiment, S. hermaphrodita seeds dressed with a suspension of A. pullulans and inoculated with A. alternata produced a higher number of seedlings with a higher health status than non-dressed seeds. Conclusions: The study demonstrated that A. alternata is transmitted from infected S. hermaphrodita seeds to developing plants and biological control limits this phenomenon.


Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2517
Author(s):  
Hazuki Kurashita ◽  
Kyohei Kuroda ◽  
Shinya Maki ◽  
Takeshi Sato ◽  
Motonori Takagi ◽  
...  

The lotus (Nelumbo nucifera Gaertn.) is widely cultivated in Asia, but a blackening disease in the lotus tuber, called “kurokawa-senchu-byo”, is a serious problem caused by the Hirschmanniella diversa Sher plant-parasitic nematode. To effectively control the disease, we must elucidate the blackening mechanisms; therefore, in this study, we performed a soil chemical analysis and an evaluation of the disease level in the lotus cultivation fields, identified the chemical components of the black spots on the lotus surface, and performed a 16S rRNA gene-based microbial community analysis of the black spots. Using linear regression analysis, a positive linear relationship with a strong correlation between the damage index values and fertilizer components such as P2O5 was observed. As a result of scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis, phosphorus (P) and iron (Fe) were found to be concentrated in the black spots of the lotus tubers. Furthermore, we found that the concentrations of P and Fe in the black spots were 1.5- and 2.7-fold higher, respectively, than those found in the healthy parts of the lotus tubers. A 16S rRNA gene analysis revealed that dissimilatory Fe(III)-reducing bacteria (DIRB) were predominant in the black spots, suggesting that these bacteria are important to the formation of P and Fe compounds in the black spots.


2021 ◽  
Vol 39 (2) ◽  
pp. 5-28
Author(s):  
Mariya Yarlykova ◽  
Yu Xunda

This article examines uniform standardized history education in Russia. It focuses primarily on the process of designing unified national history textbooks in 2013-2017, and also examines the educational reform that followed this process, along with the role of Russian society in the formulation of the textbook’s content. The new historical-cultural criteria—and the Unified textbooks based on them—are considered as a product of social contract as it was revised and approved by the different levels of Russian society: academics, parents, teachers, and government. In essence, the new textbooks are the first joint project made by the government, academics and society in the history of the Russian state. The new history textbooks are regarded as an attempt by the state and society to link Russian history with world history; previously, each discipline was studied separately. It is also an attempt to acknowledge and accept all of Russian history as one historical process of the evolution of Russian statehood, including all successes and achievements as well as black spots and wrongdoings. Although the unified textbooks are the most prudent revision of history in contemporary Russia, however there are several improvements required to redirect textbooks from being simply a tool for the construction of patriotism in schools to also being a mechanism of development of the younger generation’s critical thinking.


2021 ◽  
Vol 10 (2) ◽  
pp. 126-126
Author(s):  
D. Kandambi ◽  
N. Abeyrathna ◽  
D.S. De Silva ◽  
S. Karunarathna

The small sized, non-venomous, and fossorial colubrid snake genus Aspidura Wagler, 1830 is endemic to Sri Lanka. Aspidura ceylonensis (Günther, 1858) is rare and restricted to mid-elevation to montane and sub-montane forests at elevation of 500–1300 m a.s.l. in the Central Highlands and the Knuckles massif. It is found in cool and well-shaded forest areas, with thick moist leaflitter, woody debris, and loose soil. The usual adult body coloration on dorsum is dark reddish or dark orange, rarely yellowish, with a continuous black vertebral line and two rows of dorsolateral black spots along the body.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yu Hou ◽  
DeHui Li ◽  
YanLing Lu ◽  
HeFei Huang ◽  
WeiGuo Yang ◽  
...  

The nickel-base superalloy Hastelloy N was irradiated using 1 MeV Xe20+ and 7 MeV Xe26+ ions with displacement damage ranging from 0.5 dPa to 10 dPa at room temperature (RT). The irradiated Ni-based superalloy was characterized with transmission electron microscopy (TEM), XRD, and nanoindenter to determine the changes in microstructural evolution and nanoindentation hardness. The TEM results showed that ion irradiation induced a large number of defects such as black spots and corrugated structures and the second phase was rapidly amorphized after being irradiated to a fluence of 0.5 dPa. The XRD results showed that the Hastelloy N alloy sample did not undergo lattice distortion after ion irradiation. An obvious irradiation hardening phenomenon was observed in this study, and the hardness increased with Xe ion fluence. The pinning effect in which the defects can become obstacles to the free movement of dislocation may be responsible for the irradiation-induced hardening.


2021 ◽  
Author(s):  
Niklas Puller ◽  
Hendrik-Jorn Gunther ◽  
Gwendal Lucas ◽  
Andre Leschke ◽  
Vittorio Rocco
Keyword(s):  

2021 ◽  
Vol 889 (1) ◽  
pp. 012054
Author(s):  
Tarun Sharma ◽  
Sandeep Singh

Abstract Evaluation of in service pavements is very vital for keeping them in good serviceable condition because pavements deteriorate with age and traffic loading. To get a complete idea of the existing condition of any pavement both structural and functional evaluation are necessary. This study aims to investigate the accidental spots, traffic volume, and pavement condition. For this survey, the location of Kharar was chosen i.e. Balongi to Kharar Bus-Stand of 7 km stretch. The road initiates with intersection near Kharar bus stand and passes through many in between intersections near Sunny Enclave, VR Punjab Mall which are prime locations in that area. This road also connects with T junction and connects to NH5 / NH7 via Airport road. The data collected was processed, categorized and analyzed to generate reports for vehicle classification, hourly traffic variation, accidental black spots, pavement condition and origin & destination of trips.


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