88 research outputs found

    The activated charcoal adsorption of phenol

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    The problems of treatment of the waste water were considered in this work. The main method of the activated charcoal adsorption of phenol was investigated. The adsorption properties of the adsorbent were also considered. Along with it Langmuir's and Friendlich's adsorption isotherm has been studied and analyzed

    Highly Transparent Ceramics for the Spectral Range from 1.0 to 60.0 μm Based on Solid Solutions of the System AgBr-AgI-TlI-TlBr

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    The article is devoted to the technology for obtaining optical ceramics of AgBr-TlI and AgBr-TlBr0.46I0.54 systems and manufacturing samples with different compositions. The new heterophase crystal ceramics are transparent without absorption windows in the spectral range from 1.0 to 60.0 μm. In the ceramics' transparency spectra based on the AgBr-TlI and AgBr-TlBr0.46I0.54 systems fusibility diagrams, with an increase in the thallium halides mass fraction, as well as the replacement of the bromine ion with iodine, the maximum transparency shifts to a long infrared region. © 2021 Chinese Optics Letters.This work was supported by the Russian Science Foundation (No. 18-73-10063)

    Spinal dural arteriovenous fistulas: Pathogenesis, clinical manifestations, diagnosis, treatment

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    The paper describes spinal dural arteriovenous fistulas (SDAVF), the most common type of spinal cord vascular anomalies. SDAVFs account for 60–80% of the spinal cord vascular anomalies. The causes of SDAVFs, the specific features of their hemodynamics, and their classification remain the subject matter of disputes.SDAVFs form in dura mater tissue, on the dorsal surface of radicular cuffs. The pathogenesis of neurological disorders in SDAVF has determined the name «venous hypertensive myelopathy», a spinal cord injury occurring in their presence. Pain and paresthesias, cacesthesia (more commonly in their distal parts), and motor disorders as flail legs are observed at the onset of SDAVF in typical cases. On average, 12 to 44 months elapse to establish its diagnosis. In addition of motor and sensory disorders, sphincter impairments and sexual dysfunction are detected in the patients at the time of diagnosis. By this time, most patients have already neurological disability.The paper presents the history of studying SDAVF, the existing classifications of arteriovenous malformations and fistulas, the clinical manifestations of venous hypertensive myelopathy in SDAVF, neuroimaging findings, and treatment options

    Analysis of 3800-year-old Yersinia pestis genomes suggests Bronze Age origin for bubonic plague

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    该论文通过对青铜器时代的两个鼠疫杆菌分离株进行测序,深入剖析了鼠疫杆菌的历史。德国、俄罗斯、中国和瑞士等多国研究员共同参与了研究。这篇论文的第一作者是德国马克斯-普朗克研究所的考古遗传学专家Maria Spyrou。她和同事从俄罗斯墓穴中埋葬的九名古代人的牙齿样本入手,发现有两人感染鼠疫杆菌。之后,他们从这些个体中分离出距今约3800年的病原菌。在这项新研究中,研究人员利用液相捕获和Illumina鸟枪法测序技术,对青铜器时代的一名男子(RT5)的鼠疫杆菌和人类宿主序列进行测序,其中鼠疫杆菌基因组的平均覆盖度达到32倍。同时,他们还对另一名感染个体(RT6)的分离株进行测序,平均覆盖度为1.9倍。系统发育分析表明,RT5和RT6分离株是共同谱系的一部分,这个谱系的祖先是史上三次瘟疫大流行的罪魁祸首。除了众所周知的中世纪欧洲瘟疫大流行,鼠疫杆菌还曾造成公元6世纪的查士丁尼瘟疫和19世纪的中国大规模鼠疫。 马克斯-普朗克人类历史科学研究所的古病理学专家Kirsten Bos表示,这些结果表明“具有传播潜力的瘟疫存在的时间比我们想象得更久。”Bos是这篇论文的通讯作者之一。【Abstract】The origin of Yersinia pestis and the early stages of its evolution are fundamental subjects of investigation given its high virulence and mortality that resulted from past pandemics. Although the earliest evidence of Y. pestis infections in humans has been identified in Late Neolithic/Bronze Age Eurasia (LNBA 5000–3500y BP), these strains lack key genetic components required for flea adaptation, thus making their mode of transmission and disease presentation in humans unclear. Here, we reconstruct ancient Y. pestis genomes from individuals associated with the Late Bronze Age period (~3800 BP) in the Samara region of modern-day Russia. We show clear distinctions between our new strains and the LNBA lineage, and suggest that the full ability for flea-mediated transmission causing bubonic plague evolved more than 1000 years earlier than previously suggested. Finally, we propose that several Y. pestis lineages were established during the Bronze Age, some of which persist to the present day.We thank Cosimo Posth, Marcel Keller, Michal Feldman and Wolfgang Haak for useful insights to the manuscript, as well as Alexander Immel and Stephen Clayton for computational support. In addition, we are thankful to Guido Brandt, Antje Wissgott and Cäcilia Freund for laboratory support. M.A.S., A.H., K.I.B. and J.K. were supported by the ERC starting grant APGREID, and by the Max Planck Society. C.C.W. was supported by the Max Planck Society and the Nanqiang Outstanding Young Talents Program of Xiamen University. D.K. was supported by a Marie Heim-Vögtlin grant from the Swiss National Science Foundation

    Analysis of 3800-year-old Yersinia pestis genomes suggests Bronze Age origin for bubonic plague

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    © 2018 The Author(s). The origin of Yersinia pestis and the early stages of its evolution are fundamental subjects of investigation given its high virulence and mortality that resulted from past pandemics. Although the earliest evidence of Y. pestis infections in humans has been identified in Late Neolithic/Bronze Age Eurasia (LNBA 5000-3500y BP), these strains lack key genetic components required for flea adaptation, thus making their mode of transmission and disease presentation in humans unclear. Here, we reconstruct ancient Y. pestis genomes from individuals associated with the Late Bronze Age period (~3800 BP) in the Samara region of modern-day Russia. We show clear distinctions between our new strains and the LNBA lineage, and suggest that the full ability for flea-mediated transmission causing bubonic plague evolved more than 1000 years earlier than previously suggested. Finally, we propose that several Y. pestis lineages were established during the Bronze Age, some of which persist to the present day

    INVESTIGATION OF RADIATION RESISTANCE OF SINGLE CRYSTALS AND OPTICAL CERAMICS BASED ON THALLIUM AND SILVER HALIDES

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    The research of radiation resistance of single crystals and optical ceramics based on the systems AgCl0.75Br0.25 – TlCl0.74Br0.26; TlBr0.54I0.46 – AgCl0.75Br0.25. is presented in this paper. As a result of beta and gamma irradiation, an insignificant change in the transmittance level of the samples.Исследование выполнено за счет гранта Российского научного фонда № 21-73-10108, https://rscf.ru/project/21-73-10108/

    Terahertz Nanocrystalline Ceramics

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    Изобретение относится к новой терагерцовой (ТГц) элементной базе для диапазона 0,1-10,0 ТГц а именно оптической галогенидной нанокристаллической керамике системы TlCl0,74Br0,26 – AgI, предназначенной для передачи терагерцового и инфракрасного излучения. Керамика востребована для применения в оптике, фотонике, в лазерной и ядерной технике видимого, инфракрасного и терагерцового диапазонов. Терагерцовая нанокристаллическая керамика изготовлена на основе твердого раствора хлорида-бромида одновалентного таллия состава TlCl0,74Br0,26 и дополнительно содержит иодид серебра, при следующем соотношении компонентов, мол.%: твердый раствор TlCl0,74Br0,26 66-96; йодид серебра 34-4. Технический результат изобретения: получение нанокристаллического керамического материала для изготовления методом экструзии нового класса гибких нанокристаллических световодов, устойчивых к УФ и радиационному излучениям. 3 ил., 3 пр.FIELD: terahertz elements. SUBSTANCE: invention relates to a new terahertz (THz) element base for the range of 0.1-10.0 THz, namely, optical halide nanocrystalline ceramics of the TlCl0.74Br0.26 - AgI system, designed to transmit terahertz and infrared radiation. Ceramics is in demand for applications in optics, photonics, laser and nuclear technology in the visible, infrared, and terahertz ranges. Terahertz nanocrystalline ceramics is made on the basis of a solid solution of monovalent thallium chloride-bromide composition TlCl0.74Br0.26 and additionally contains silver iodide, in the following ratio, mol.%: solid solution TlCl0.74Br0.26 66-96; silver iodide 34-4. EFFECT: obtaining a nanocrystalline ceramic material for the production by extrusion of a new class of flexible nanocrystalline light guides resistant to UV and radiation. 1 cl, 3 dwg, 3 ex

    Social Determinants of Long Lasting Insecticidal Hammock-Use Among the Ra-Glai Ethnic Minority in Vietnam: Implications for Forest Malaria Control

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    BACKGROUND: Long-lasting insecticidal hammocks (LLIHs) are being evaluated as an additional malaria prevention tool in settings where standard control strategies have a limited impact. This is the case among the Ra-glai ethnic minority communities of Ninh Thuan, one of the forested and mountainous provinces of Central Vietnam where malaria morbidity persist due to the sylvatic nature of the main malaria vector An. dirus and the dependence of the population on the forest for subsistence - as is the case for many impoverished ethnic minorities in Southeast Asia. METHODS: A social science study was carried out ancillary to a community-based cluster randomized trial on the effectiveness of LLIHs to control forest malaria. The social science research strategy consisted of a mixed methods study triangulating qualitative data from focused ethnography and quantitative data collected during a malariometric cross-sectional survey on a random sample of 2,045 study participants. RESULTS: To meet work requirements during the labor intensive malaria transmission and rainy season, Ra-glai slash and burn farmers combine living in government supported villages along the road with a second home at their fields located in the forest. LLIH use was evaluated in both locations. During daytime, LLIH use at village level was reported by 69.3% of all respondents, and in forest fields this was 73.2%. In the evening, 54.1% used the LLIHs in the villages, while at the fields this was 20.7%. At night, LLIH use was minimal, regardless of the location (village 4.4%; forest 6.4%). DISCUSSION: Despite the free distribution of insecticide-treated nets (ITNs) and LLIHs, around half the local population remains largely unprotected when sleeping in their forest plot huts. In order to tackle forest malaria more effectively, control policies should explicitly target forest fields where ethnic minority farmers are more vulnerable to malaria
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