bluuebunny/crossref_metadata_2025 huggingface dataset:
PM014 attenuates radiation-induced pulmonary fibrosis via regulating NF-kB and TGF-b1/NOX4 pathways
Authors: Park Sung-Hyo , Kim Jee-Youn , Kim Jin-Mo , Yoo Byeong Rok , Han Song Yee , Jung Yoo Jin , Bae Hyunsu , Cho Jaeho
Published: September 2020

Radiation therapy is the mainstay in the treatment of lung cancer, and lung fibrosis is a radiotherapy-related major side effect that can seriously reduce patient’s quality of life. Nevertheless, effective strategies for protecting against radiation therapy-induced fibrosis have not been developed. Hence, we investigated the radioprotective effects and the underlying mechanism of the standardized herbal extract PM014 on radiation-induced lung fibrosis. Ablative radiation dose of 75 Gy was focally delivered to the left lung of mice. We evaluated the effects of PM014 on radiation-induced lung fibrosis in vivo and in an in vitro model. Lung volume and functional changes were evaluated using the micro-CT and flexiVent system. Fibrosis-related molecules were evaluated by immunohistochemistry, western blot, and real-time PCR. A orthotopic lung tumour mouse model was established using LLC1 cells. Irradiated mice treated with PM014 showed a significant improvement in collagen deposition, normal lung volume, and functional lung parameters, and these therapeutic effects were better than those of amifostine. PM104 attenuated radiation-induced increases in NF-κB activity and inhibited radiation-induced p65 translocation, ROS production, DNA damage, and epithelial-mesenchymal transition. PM104 effectively alleviated fibrosis in an irradiated orthotopic mouse lung tumour model while not attenuating the efficacy of the radiation therapy by reduction of the tumour. Standardized herbal extract PM014 may be a potential therapeutic agent that is able to increase the efficacy of radiotherapy by alleviating radiation-induced lung fibrosis.
Optimised spectral effects of programmable LED arrays (PLA)s on bioelectricity generation from algal-biophotovoltaic devices
Authors: Ng Fong-Lee , Phang Siew-Moi , Lan Boon Leong , Kalavally Vineetha , Thong Cheng-Han , Chong Kian-Ted , Periasamy Vengadesh , Chandrasekaran Karthikeyan , kumar G. Gnana , Yunus Kamran , Fisher Adrian C.
Published: September 2020

The biophotovoltaic cell (BPV) is deemed to be a potent green energy device as it demonstrates the generation of renewable energy from microalgae; however, inadequate electron generation from microalgae is a significant impediment for functional employment of these cells. The photosynthetic process is not only affected by the temperature, CO2concentration and light intensity but also the spectrum of light. Thus, a detailed understanding of the influences of light spectrum is essential. Accordingly, we developed spectrally optimized light using programmable LED arrays (PLA)s to study the effect on algae growth and bioelectricity generation.Chlorellais a green microalga and contains chlorophyll-a(chl-a), which is the major light harvesting pigment that absorbs light in the blue and red spectrum. In this study,Chlorellais grown under a PLA which can optimally simulate the absorption spectrum of the pigments inChlorella. This experiment investigated the growth, photosynthetic performance and bioelectricity generation ofChlorellawhen exposed to an optimally-tuned light spectrum. The algal BPV performed better under PLA with a peak power output of 0.581 mW m−2for immobilized BPV device on day 8, which is an increase of 188% compared to operation under a conventional white LED light source. The photosynthetic performance, as measured using pulse amplitude modulation (PAM) fluorometry, showed that the optimized spectrum from the PLA gave an increase of 72% in the rETRmax value (190.5 μmol electrons m−2 s−1), compared with the conventional white light source. Highest algal biomass (1100 mg L−1) was achieved in the immobilized system on day eight, which translates to a carbon fixation of 550 mg carbon L−1. When artificial light is used for the BPV system, it should be optimized with the light spectrum and intensity best suited to the absorption capability of the pigments in the cells. Optimum artificial light source with algal BPV device can be integrated into a power management system for low power application (eg. environment sensor for indoor agriculture system).
Antimicrobials use and resistance on integrated poultry-fish farming systems in the Ayeyarwady Delta of Myanmar
Authors: Gibson Justine S. , Wai Honey , Oo Shwe Sin May Lwin , Hmwe Ei Moh Moh , Wai Soe Soe , Htun Lat Lat , Lim Hwee Ping , Latt Zin Min , Henning Joerg
Published: September 2020

Antimicrobials are used to support livestock health and productivity, but might pose a risk for the development of antimicrobial resistance; in particular, when multiple livestock species are raised together in production systems. On integrated chicken-fish farms, chickens are raised over fish ponds and poultry faeces is excreted into the ponds. We investigated antimicrobial usage and the antimicrobial susceptibility of Escherichia coli cultured from poultry faeces on 301 integrated farms in Ayeyarwady Delta of Myanmar. Antimicrobials were used by 92.4% of farmers for chickens, but they were not applied to fish. The most common antimicrobials used were Octamix (amoxicillin and colistin sulfate) on 28.4%, enrofloxacin on 21.0% and amoxicillin on 16% of farms. Overall, 83.1% (152/183) of the E. coli were resistant to at least one antimicrobial. The highest level of resistance was to amoxicillin (54.6%), tetracycline (39.9%), sulfamethoxazole/trimethoprim (35.5%) and enrofloxacin (34.4%). Multidrug resistance was identified in 42.4% of isolates. In general, we found similar levels of antimicrobial resistance in non-users of antimicrobials as in users of antimicrobials for more commonly applied antimicrobials. Overall, antimicrobial resistance was lower in chickens on these integrated farms in Myanmar, compared to poultry farms in other countries of South East and East Asia.
The last strategy for re-dissemination of HPV vaccination in Japan while still under the suspension of the governmental recommendation
Authors: Ueda Yutaka , Yagi Asami , Abe Hazuki , Nakagawa Satoshi , Minekawa Ryoko , Kuroki Haruo , Miwa Ayako , Kimura Tadashi
Published: September 2020

In Japan, the governmental recommnendation of HPV vaccine has been suspended since June 2013, due to media reports of alleged adverse vaccination events. Although evidence of effectiveness and safety of the HPV vaccine has been universally demonstrated, and the medical and academic organizations across Japan have requested the resumption of the government’s recommendation, the Japanese government has not changed their official stance towards the HPV vaccine. Under the current suspension of the national government’s recommendation, one local government Isumi City started sending a leaflet containing information of cervical cancer and HPV vaccine, but not recommendation for the vaccine, to the tagted girls born in the fiscal year (FY) 2003. The cumulative vaccination rate of them reached 10.07% (14/139), which was significantly higher than that (0.00%) for girls born in FY 2002 who did not receive such a leaflet (p < 0.001). We sincerely ask the national government to change their stance towards the HPV vaccine. We also strongly suggest that, in the meantime, local governments immediately begin to provide an appropriate information of cervical cancer and HPV vaccine to the targeted girls and their parents in a way similar to what Isumi City has now shown to be effective.
Genomic analysis reveals high virulence and antibiotic resistance amongst phage susceptible Acinetobacter baumannii
Authors: Leungtongkam Udomluk , Thummeepak Rapee , Kitti Thawatchai , Tasanapak Kannipa , Wongwigkarn Jintana , Styles Kathryn M. , Wellington Elizabeth M. H. , Millard Andrew D. , Sagona Antonia P. , Sitthisak Sutthirat
Published: September 2020

In this study, we examined the association between antimicrobial resistance, CRISPR/Cas systems and virulence with phage susceptibility inAcinetobacter baumanniiand investigated draft genomes of phage susceptible multidrug resistantA. baumanniistrains from Thailand. We investigated 230A. baumanniistrains using 17 lyticA. baumanniiphages and the phage susceptibility was 46.5% (107/230). Phage susceptibility was also associated with resistance to numerous antibiotics (p-value < 0.05). We also found association between biofilm formation and the presence ofompAgene among phage susceptibleA. baumanniistrains (p-value < 0.05).A. baumanniiisolates carryingcas5or combinations of two or three othercasgenes, showed a significant increase in phage resistance. Whole-genome sequences of seven phage susceptibleA. baumanniiisolates revealed that six groups of antibiotic resistance genes were carried by all seven phage susceptibleA. baumannii. All strains carried biofilm associated genes and two strains harbored complete prophages, acquired copper tolerance genes, and CRISPR-associated (cas) genes. In conclusion, our data exhibits an association between virulence determinants and biofilm formation among phage susceptibleA. baumanniistrains. These data help to understand the bacterial co-evolution with phages.
Topologically selective islet vulnerability and self-sustained downregulation of markers for β-cell maturity in streptozotocin-induced diabetes
Authors: Hahn Max , van Krieken Pim P. , Nord Christoffer , Alanentalo Tomas , Morini Federico , Xiong Yan , Eriksson Maria , Mayer Jürgen , Kostromina Elena , Ruas Jorge L. , Sharpe James , Pereira Teresa , Berggren Per-Olof , Ilegems Erwin , Ahlgren Ulf
Published: September 2020

Mouse models of Streptozotocin (STZ) induced diabetes represent the most widely used preclinical diabetes research systems. We applied state of the art optical imaging schemes, spanning from single islet resolution to the whole organ, providing a first longitudinal, 3D-spatial and quantitative account of β-cell mass (BCM) dynamics and islet longevity in STZ-treated mice. We demonstrate that STZ-induced β-cell destruction predominantly affects large islets in the pancreatic core. Further, we show that hyperglycemic STZ-treated mice still harbor a large pool of remaining β-cells but display pancreas-wide downregulation of glucose transporter type 2 (GLUT2). Islet gene expression studies confirmed this downregulation and revealed impaired β-cell maturity. Reversing hyperglycemia by islet transplantation partially restored the expression of markers for islet function, but not BCM. Jointly our results indicate that STZ-induced hyperglycemia results from β-cell dysfunction rather than β-cell ablation and that hyperglycemia in itself sustains a negative feedback loop restraining islet function recovery.
Structural dynamics in Ni–Fe catalysts during CO2 methanation – role of iron oxide clusters
Authors: Serrer Marc-André , Gaur Abhijeet , Jelic Jelena , Weber Sebastian , Fritsch Charlotte , Clark Adam H. , Saraçi Erisa , Studt Felix , Grunwaldt Jan-Dierk
Published: September 2020

Operando XAS coupled with MES supported by DFT unravel the highly dynamic nature of Ni–Fe catalysts during CO2 methanation and beneficial formation of iron oxide clusters.
Current status and future prospects of metal–organic frameworks at the interface of dye-sensitized solar cells
Authors: Khajavian Ruhollah , Mirzaei Masoud , Alizadeh Hanie
Published: September 2020

In this Frontier Article recent progresses and challenges at the interface of metal–organic frameworks and dye-sensitized solar cells are highlighted and discussed.
Multifunctionalization of cellulose microfibrils through a cascade pathway entailing the sustainable Passerini multi-component reaction
Authors: Pettignano Asja , Leguy Julien , Heux Laurent , Jean Bruno , Charlot Aurélia , Fleury Etienne
Published: September 2020

Through a cascade of chemical derivatizations involving the green Passerini three-component reaction (P-3CR), we describe herein the multifunctionnalization of cellulose microfibrils (MFC) previously subjected to a periodate oxidation step.
Photochemical methods for deuterium labelling of organic molecules
Authors: Ranjan Prabhat , Pillitteri Serena , Van der Eycken Erik V. , Sharma Upendra K.
Published: September 2020

This tutorial review is intended as a foundation for the further development of novel photocatalytic strategies to achieve deuterium incorporation using mild and sustainable conditions.
Pharmacophore-based screening of diamidine small molecule inhibitors for protein arginine methyltransferases
Authors: Qian Kun , Yan Chunli , Su Hairui , Dang Tran , Zhou Bo , Wang Zhenyu , Zhao Xinyang , Ivanov Ivaylo , Ho Meng-Chiao , Zheng Y. George
Published: September 2020

A new diamidine compound was identified as a potent PRMT1 inhibitor that blocked leukaemia cell proliferation and decreased arginine asymmetric dimethylation.
Further insights into the Fe(ii) reduction of 2-line ferrihydrite: a semi in situ and in situ TEM study
Authors: Gomez Mario Alberto , Jiang Ruonan , Song Miao , Li Dongsheng , Lea Alan Scott , Ma Xu , Wang Haibo , Yin Xiuling , Wang Shaofeng , Jia Yongfeng
Published: September 2020

The catalytic reduction of nano-crystalline 2-line ferrihydrite with Fe(ii)(aq) doesn't occur via direct pathways but rather through new intermediate steps.
Single-domain antibody C7b for address delivery of nanoparticles to HER2-positive cancers
Authors: Vorotnikov Yuri A. , Novikova Evgeniya D. , Solovieva Anastasiya O. , Shanshin Daniil V. , Tsygankova Alphiya R. , Shcherbakov Dmitrii N. , Efremova Olga A. , Shestopalov Michael A.
Published: September 2020

Single-domain antibody C7b is benchmarked against trastuzumab for targeted delivery of photoactive silica nanoparticles to a HER2 overexpressing cancer cell line and tissue.
Supramolecular secondary helical structures in solid-state N-protected amino acids
Authors: Zong Zhaohui , Hao Aiyou , Xing Pengyao
Published: September 2020

Helix is an important secondary structure in proteins and polypeptides, which, however, has rarely been recognized in amino acids or their simple derivatives.
Silver assisted stereo-directed assembly of branched peptide nucleic acids into four-point nanostars
Authors: Madhanagopal Bharath Raj , Kumar Jatish , Ganesh Krishna N.
Published: September 2020

Branched chiral peptide nucleic acidsbr(4S/R)-PNA with three arms of PNA-C4strands were constructed on a central chiral core of 4(R/S)-aminoproline as the branching center.
Visible-light reversible photopolymerisation: insights via online photoflow – electrospray ionisation – mass spectrometry
Authors: Van De Walle Matthias , Petit Charlotte , Blinco James P. , Barner-Kowollik Christopher
Published: September 2020

Herein, we introduce a scalable photopolyaddition polymerisations using the pyrene-chalcone [2+2]-cycloaddition and monitor the photodepolymerisation process via an online photoflow – electrospray ionisation mass spectrometry setup.
Human stem cell response to layered zirconium phosphate
Authors: Nakamura Jin , Endo Kanta , Sugawara-Narutaki Ayae , Ohtsuki Chikara
Published: September 2020

This study aims to evaluate the in vitro cytocompatibility of layered zirconium phosphate (ZP) and its derivative material that was organically modified using glycerophosphate (ZGP).
O2activation by core–shell Ru13@Pt42particles in comparison with Pt55particles: a DFT study
Authors: Lu Jing , Zhu Bo , Sakaki Shigeyoshi
Published: September 2020

In this theoretical study by DFT computations, characteristic features of the Ru13@Pt42core–shell particle in O2activation are clearly discussed in comparison with Pt55.
Effects of carbon and nitrogen plasma immersion ion implantation on bioactivity of zirconia
Authors: Guo Shuqin , Liu Na , Liu Ke , Li Ying , Zhang Wei , Zhu Biao , Gu Bin , Wen Ning
Published: September 2020

Zirconia is considered the most promising alternative material to titanium implants.
Development of an on-chip sample injection system with a 6-port valve incorporated in a microchip
Authors: Morioka Kazuhiro , Sato Hina , Morita Kenji , Akihide Hemmi , Nakajima Hizuru , Shoji Atsushi , Yanagida Akio
Published: September 2020

We demonstrate on-chip sample injection using a 6-port valve incorporated in a microchip.
Synthesis of chiral 1,4-oxazepane-5-carboxylic acids from polymer-supported homoserine
Authors: Králová Petra , Lemrová Barbora , Maloň Michal , Soural Miroslav
Published: September 2020

The preparation of novel 1,4-oxazepane-5-carboxylic acids bearing two stereocenters is reported in this article.
Total syntheses of spiroviolene and spirograterpene A: a structural reassignment with biosynthetic implications
Authors: Chi Hyung Min , Cole Charles J. F. , Hu Pengfei , Taylor Cooper A. , Snyder Scott A.
Published: September 2020

Concise syntheses of spiroviolene and spirograterpene A have been achieved from a common intermediate, indicating a structure revision of one is necessary along with implications for its biosynthesis.
Correction: Structural determinants of macrocyclization in substrate-controlled lanthipeptide biosynthetic pathways
Authors: Bobeica Silvia C. , Zhu Lingyang , Acedo Jeella Z. , Tang Weixin , van der Donk Wilfred A.
Published: September 2020

Correction for ‘Structural determinants of macrocyclization in substrate-controlled lanthipeptide biosynthetic pathways’ by Silvia C. Bobeica et al., Chem. Sci., 2020, DOI: 10.1039/d0sc01651a.
Underlying mechanisms in microbial solar cells: how modeling can help
Authors: Beauzamy Léna , Lemaître Frédéric , Derr Julien
Published: September 2020

Using modeling we uncoupled and quantified the different rate constants implicated in microbial solar cells: mediator fluxes in and out of microbes, oxidation at the electrode, photo-reduction inside the microbe, and degradation over time.
Progress and prospects of CZTSSe/CdS interface engineering to combat high open-circuit voltage deficit of kesterite photovoltaics: a critical review
Authors: Nisika  , Kaur Kulwinder , Kumar Mukesh
Published: September 2020

We review critical aspects of interface engineering of the absorber–buffer heterojunction in CZTSSe solar cells and highlight the importance of tools that are essential to identify and eradicate the root causes of low efficiency.
Quantum dot-carbonaceous nanohybrid composites: preparation and application in electrochemical energy storage
Authors: Shen Ting , Yang Liping , Pam Mei Er , Shi Yumeng , Yang Hui Ying
Published: September 2020

Quantum dot (QD)-based materials have been employed to enhance thermodynamic and kinetic properties of electrochemical reactions for energy storage and engineering.
Graphdiyne-based Pd single-atom catalyst for semihydrogenation of alkynes to alkenes with high selectivity and conversion under mild conditions
Authors: Yin Xue-Peng , Tang Shang-Feng , Zhang Chao , Wang Hong-Juan , Si Rui , Lu Xiu-Li , Lu Tong-Bu
Published: September 2020

Pd–GDY catalysts show an evident dependence on Pd species size in hydrogenation reaction. Specifically, Pds–GDY shows superior performance in semihydrogenation of phenylacetylene with much higher TOF of 6290 h−1 and selectivity of 99.3% at 100% conversion.
Tuning the phase stability and surface HER activity of 1T′-MoS2 by covalent chemical functionalization
Authors: Chen Jiu , Li Fuhua , Tang Yurong , Tang Qing
Published: September 2020

Chemical functionalization can significantly improve the stability of meta-stable 1T′-MoS2 and tune the surface HER activity.
Structure determination and negative differential resistance of tetraarylporphyrin/polyoxometalate 2 : 1 complexes
Authors: Yamazaki Yoshito , Yamashita Ken-ichi , Tani Yosuke , Aoyama Tomoya , Ogawa Takuji
Published: September 2020

The tetraarylporphyrin/POM complexes with CT character show negative differential resistance because of the memristor-like behavior.
A Phonomotor Approach to Apraxia of Speech Treatment
Authors: Bislick Lauren
Published: September 2020

Purpose

This study continued Phase I investigation of a modified Phonomotor Treatment (PMT) Program on motor planning in two individuals with apraxia of speech (AOS) and aphasia and, with support from prior work, refined Phase I methodology for treatment intensity and duration, a measure of communicative participation, and the use of effect size benchmarks specific to AOS.

Method

A single-case experimental design with multiple baselines across behaviors and participants was used to examine acquisition, generalization, and maintenance of treatment effects 8–10 weeks posttreatment. Treatment was distributed 3 days a week, and duration of treatment was specific to each participant (criterion based). Experimental stimuli consisted of target sounds or clusters embedded nonwords and real words, specific to each participants' deficit.

Results

Findings show improved repetition accuracy for targets in trained nonwords, generalization to targets in untrained nonwords and real words, and maintenance of treatment effects at 10 weeks posttreatment for one participant and more variable outcomes for the other participant.

Conclusions

Results indicate that a modified version of PMT can promote generalization and maintenance of treatment gains for trained speech targets via a multimodal approach emphasizing repeated exposure and practice. While these results are promising, the frequent co-occurrence of AOS and aphasia warrants a treatment that addresses both motor planning and linguistic deficits. Thus, the application of traditional PMT with participant-specific modifications for AOS embedded into the treatment program may be a more effective approach. Future work will continue to examine and maximize improvements in motor planning, while also treating anomia in aphasia.
Research on the breaking branch for a hybrid DC circuit breaker in±500 kV voltage‐sourced converter high‐voltage direct current grid
Authors: Feng Lei , Gou Ruifeng , Zhuo Fang , Yang Xiaoping , Zhang Fang
Published: September 2020

In order to construct the voltage‐sourced converter high‐voltage direct current grids, the high capacity direct current circuit breakers (DCCBs) are in demand. The hybrid DCCB has been the mainstream proposal, where the high‐voltage solid‐state switch (HVSS) is the key component for breaking the final fault current. Investigating the current commutation between the breaking branch and energy‐absorbing branch, a hybrid DCCB with repositioned current commutation module (CCM) and redesigned HVSS is proposed in this study. By analysing the equivalent circuit of the CCM and HVSS, the detailed transient stages during current interruption procedure have been revealed, and the comparisons of different topologies for HVSS are made in‐depth. The repositioned CCM can greatly decrease the transient voltage stress for HVSS and CCM whilst the improved HVSS including metal oxide varistor can maintain better interruption performances. Then the actual prototypes are developed to verify the effectiveness of the improved hybrid DCCB topology. In the end, a 500 kV DCCB is realised based on the proposed HVSS, which can ensure the reliability and convenience of the hybrid DCCB.
Comparative evaluation of a family of isolated Ćuk DC/DC converter with step‐up techniques
Authors: Faistel Tiago Miguel Klein , Guisso Ronaldo Antonio , Andrade António Manuel Santos Spencer , da Silva Martins Mário Lúcio
Published: September 2020

In this study, a comparative evaluation of a family of isolated Ćuk DC/DC converter with step‐up techniques is presented. The voltage gain techniques are the reduced redundant power processing and the voltage multiplier. In addition, a detailed comparative analysis of the converters is showed. This comparison comprises features, such as the principle of operation, voltage gain curves, voltage and current stresses, design methodology, and estimated losses. By these comparisons, the main features and constraints of the analysed converters are identified. Four 200 W prototypes were constructed and evaluated in the laboratory. The isolated Ćuk converter with voltage multiplier showed the best performance and a peak efficiency of 95.86%.
Using sliding mode observers to estimate BtuB concentration from measured vitamin B12 concentration
Authors: Abbadi Mohammad , Spurgeon Sarah , Warren Martin , Khan Naziyat , Kräutler Bernhard
Published: September 2020

A simple model for the B12 ‐riboswitch regulatory network in Escherichia coli is first described and the same analysis is applied when changing the strain to Salmonella enterica. Model validation is undertaken by linking the dynamics of the riboswitch model to bacterial growth and comparing the results obtained with in vivo experimental measurements. Measurements of bacterial growth are relatively straightforward to obtain experimentally, but experimental measurements relating to the operation of the riboswitch are more difficult. Using the validated model, sliding mode observer design methods are used to estimate BtuB given measurements of the concentration of vitamin B12. The sliding mode approach is selected because of its inherent robustness properties as well as for the ease of implementation. Validation of the estimates of BtuB produced by the observer is undertaken by comparing the BtuB and vitamin B12 concentrations estimated from the observer with green fluorescent protein production and the concentration of vitamin B12 obtained experimentally. These experimental results also provide further validation of the underpinning mathematical model. The results establish that using a sliding mode observer as a soft sensor is a useful approach to explore the operation of a vitamin B12 riboswitch given measurements of the concentration of vitamin B12.
Self-generated ultraviolet radiation in molecular shock waves
Authors: Lehmann A. , Godard B. , Pineau des Forêts G. , Falgarone E.
Published: September 2020

Context. Shocks are ubiquitous in the interstellar and intergalactic media, where their chemical and radiative signatures reveal the physical conditions in which they arise. Detailed astrochemical models of shocks at all velocities are necessary to understand the physics of many environments including protostellar outflows, supernova remnants, and galactic outflows.

Aims. We present an accurate treatment of the self-generated ultraviolet (UV) radiation in models of intermediate velocity (VS = 25–60 km s−1), stationary, weakly magnetised, J-type, molecular shocks. We show how these UV photons modify the structure and chemical properties of shocks and quantify how the initial mechanical energy is reprocessed into line emission.

Methods. We develop an iterative scheme to calculate the self-consistent UV radiation field produced by molecular shocks. The shock solutions computed with the Paris–Durham shock code are post-processed using a multi-level accelerated Λ-iteration radiative transfer algorithm to compute Lyman α, Lyman β, and two-photon continuum emission. The subsequent impacts of these photons on the ionisation and dissociation of key atomic and molecular species as well as on the heating by the photoelectric effect are calculated by taking the wavelength dependent interaction cross-sections and the fluid velocity profile into account. This leads to an accurate description of the propagation of photons and the thermochemical properties of the gas in both the postshock region and in the material ahead of the shock called the radiative precursor. With this new treatment, we analyse a grid of shock models with velocities in the range VS = 25–60 km s−1, propagating in dense (nH ≥ 104 cm−3) and shielded gas.

Results. Self-absorption traps Lyα photons in a small region in the shock, though a large fraction of this emission escapes by scattering into the line wings. We find a critical velocity VS ~ 30 km s−1 above which shocks generate Lyα emission with a photon flux exceeding the flux of the standard interstellar radiation field. The escaping photons generate a warm slab of gas (T ~ 100 K) ahead of the shock front as well as pre-ionising C and S. Intermediate velocity molecular shocks are traced by bright emission of many atomic fine structure (e.g. O and S) and metastable (e.g. O and C) lines, substantive molecular emission (e.g. H2, OH, and CO), enhanced column densities of several species including CH+ and HCO+, as well as a severe destruction of H2O. As much as 13–21% of the initial kinetic energy of the shock escapes in Lyα and Lyβ photons if the dust opacity in the radiative precursor allows it.

Conclusions. A rich molecular emission is produced by interstellar shocks regardless of the input mechanical energy. Atomic and molecular lines reprocess the quasi totality of the kinetic energy, allowing for the connection of observable emission to the driving source for that emission.
Structural and geomechanical models of gold deposits in the Amur region (Russia)
Authors: Rasskazov Igor , Kryukov Viktor , Potapchuk Marina
Published: September 2020

A large number of gold deposits are concentrated in the Russian part of the Amur river basin. Gold units are characterized by various formation conditions, and, due to this, by a variety of structural factors, as well as stability of rock masses. Structural features, qualities and properties of ore-bearing rocks determine the specifics of choosing mining systems for the units. Geological and geomechanical data obtained in the course of exploration and exploitation of objects allowed us to identify groups of deposits with similar genetic conditions and form common features of their development through the development of appropriate models. There are five major groups of gold deposits. They are represented by deposits formed in epiplatform conditions of young volcanism, in intrusive-tectonic and intrusive-dome structures of Cretaceous age, in metamorphic domes, as well as in tectonic wedges. The selected groups of deposits are localized in masses with different rock stability. In accordance with these features, we developed structural and geomechanical models of gold deposits in the Amur region. The models are used for correcting the methodology of studying deposits and justifying rational methods of their development.
Estimation of operating costs and energy consumption in beneficiation of alluvial gold deposits
Authors: Seryi Ruslan , Alekseev Vladimir
Published: September 2020

There are many scientific and practical works related to the identification and assessment of factors affecting the efficiency of beneficiation of placer sands at the sluice box, while the energy consumption of the beneficiation process, as well as assessing the efficiency of the sand screening process and the cost of maintaining the devices, is given little attention. Studies of the energy consumption of sand washing, carried out at several alluvial deposits, made it possible to identify the most energyconsuming devices, as well as to compare the energy expended for transporting rock through processing plants and to provide solid to liquid ratio during beneficiation at sluice boxes.
Experimental research of gold migration influenced by cyclic flooding-drainage of rock mass
Authors: Taganov Vitaly , Gevalo Kirill , Alekseeva Ekaterina
Published: September 2020

Efficient development of man-made placers is subject to the introduction of new technological solutions, as well as implementing the possibility of choosing the optimal design and technological indicators of mining and processing equipment, depending on the combination of influencing natural, design and technological factors. The most important research goal is the invention of new innovative technologies. To solve these problems, the direction of research on the development and theoretical substantiation of geotechnology for the development of technogenic alluvial deposits was determined and is being developed on the basis of the intra-dump concentration of valuable components, which ensures the formation of an enriched zone in the near-bed area. In order to develop the technology, the authors carried out large-scale theoretical and experimental studies to study the nature and degree of influence of a number of factors that form the basis of the technology on the migration and concentration of gold particles in the man-made rock mass, as well as determining the technological parameters and modes of flooding and drainage of the rock mass.
Research of the formation of zones of stress concentration and dynamic manifestations based on seismoacoustic monitoring data in the fields of the Kola Peninsula
Authors: Rasskazov Maxim , Tereshkin Andrey , Tsoi Denis , Konstantinov Alexander , Miroshnikov Vladimir , Bagautdinov Ilya , Kozhogulov Kamchibek
Published: September 2020

The article presents the results of geomechanical studies to assess the rock-bump hazard of the rock mass in the deposits (Kukisvumchorrskoe and Apatite Circus) of the Kola Peninsula using a special set of technical means, including the automated seismoacoustic system for monitoring rock pressure, “Prognoz-ADS”, and the local geoacoustic device “Prognoz-L”, developed at The Institute of Mining of the FEB RAS. Based on the measurement and analysis of parameters of seismoacoustic events reflecting geomechanical processes in the developed mountain range, we constructed maps of seismoacoustic activity and volumetric mining and geological models of mines. Using these tools, it becomes possible to assess the rock-bump hazard in these deposits and identify hotspots for emerging dangerous geodynamic events at an early stage, which allows us to take the necessary security measures to prevent them in advance.
The integrated geodetic monit oring system of open pit slopes in hard rock massifs
Authors: Kozyrev Anatolii , Kasparian Eduard , Rozanov Ivan
Published: September 2020

The article describes an experience in organizing the integrated geomechanical monitoring in high-strength hard rock massifs using the longstanding GPS and optical distance measurements in the Zhelezny open pit, Kovdorsky GOK JSC, as well as measurements with the IBIS FM interferometric radar. The application of the integrated monitoring system in the Zhelezny open pit has allowed accumulation of significant statistical material, which made it possible to identify the patterns of the rock mass deformation development, determine the limiting parameters and develop several regulatory documents for observing and processing the measurement results of the benches and open pit walls displacements.
Development of explosive breaking principles for the ores prone to overgrinding
Authors: Rozhkov Artem , Sokolov Igor , Antipin Yuri , Baranovsky Kirill
Published: September 2020

In underground mining of valuable non-metallic raw materials, non-ferrous and precious metal ores, the problem of overgrinding of raw materials as a result of blasting operations is quite acute. For ores of nonferrous and precious metals, represented by strong rocks, the effect of increased concentration of ore minerals in small classes of ore is characteristic. Due to the process of segregation of the mass in ore drawing, small fractions accumulate in significant quantities on the lying side of the mine goaf and on the roughness of its surface. Such ore is often simply lost. It is rational to create conditions for reducing the yield of small fractions already at the stage of separating the ore from the array. Therefore, the development of technological methods for managing the quality of mining enterprise products and methods for improving the completeness of extracting mineral reserves is an urgent scientific and technical task. To solve this problem, a number of model and full-scale experiments were conducted to identify the dependence of the nature of destruction on the method and parameters of blasting, followed by statistical evaluation of the results. The principles of determining the parameters of the technology for breaking valuable ores that are prone to overgrinding are established.
Investigation of geomechanical parameters of rock mass condition of Magnezitovaya mine**
Authors: Krinitsyn Roman , Sentyabov Sergey
Published: September 2020

Mining is a sphere of human activity connected with extraction of minerals from Earth’s interior in conditions of alternating change of the sizes of Earth accompanied by change of the stress-deformed state (SDS) of the rock mass, resulting in sudden destructions of rock structures and earthquakes, with considerable human victims.

The results of long-term geodeformation monitoring of natural stresses at Ural mines conducted by the Laboratory of geodynamics and mining pressure of the Ural Branch of Russian Academy of Sciences over the past 20 years have allowed us to offer new, more modern structure of the natural stress field with a reference to their changes in time. The Laboratory of geodynamics and mining pressure of the Institute of Geodynamics of the Ural Branch of Russian Academy of Sciences has created the geodeformation field test site at the Magnezitovaya mine [1] This field test site allows to quickly track the changes in the stress state by deformation methods and to react in time to the changes in the stress state of the rock mass. And by applying the measures to control the state of the rock mass, the company’s personnel ensure the safety of room work at the deposit. This allows to minimize the occurrence of the rock pressure in static and dynamic forms, and thus to ensure the safety of people working in underground conditions.
Deformation waves from distant earthquakes as a trigger mechanism for activating geodynamic processes in rock mass
Authors: Lugovoy Vladimir , Tsoi Denis , Rasskazov Maksim , Kozhogulov Kamchibek
Published: September 2020

The results of experimental studies with a laser strainmeter and a multichannel automated geoacoustic rock pressure control system “PROGNOZ ADS” aimed at identifying the nature of the effect of deformation waves from distant earthquakes on the geodynamic activity of the monitored rock mass are presented. The quantitative and energy characteristics of geoacoustic emission before and after the arrival of deformation waves in the controlled rock mass are analyzed. The analysis performed indicates a trigger mechanism of the influence of a distant earthquake on the geodynamic activity of the rock mass. It is noted that the direction of arrival of the deformation wave is an essential factor in the intensification of geodynamic activity in the rock mass. The experiments also revealed the characteristics of rock burst precursors when registering deformation waves in the low-frequency range.
The evolution of thick coal seams mining methods in China
Authors: Jianyong Qiao , Zhiqiang Wang , Jingli Zhao
Published: September 2020

The article is shown that the main methods used in China for coal mining from thick seams at the moment are two methods the Complex mechanized method of developing seams at their full capacity (used only in simple geological conditions and is an additional method for the following) and Complex mechanized mining method with coal production (which is used mainly, including in difficult conditions). Despite the fact that these methods have positively proven themselves over the years, their use has a number of significant drawbacks, including a low extraction rate, an increased risk of endogenous combustion and rock burst, and others. Currently, a promising way is a development method with a diagonal (cross-shaped) arrangement of drifts, which helps to eliminate many of the shortcomings of previous methods, including a low recovery coefficient, the risk of spontaneous combustion, the need to support the drift and others. It is expected that this method will be widely used for underground coal mining in deep mines in China with difficult mining and geological conditions.
Experimental modelling of a mine working failure under nonuniformly distributed compression
Authors: Suknev Sergey
Published: September 2020

This paper presents a theoretical and experimental study of the fracture of a quasi-brittle geomedium containing a cylindrical opening and subjected to a nonuniformly distributed compressive load. Laboratory tests are carried out using hydrated gypsum plaster as a model rock-like material. High-strength plaster specimens demonstrate brittle fracture, while specimens made of plaster of Paris show quasi-brittle fracture. In this case, the application of the known criteria does not allow obtaining satisfactory estimates of the fracture load. New nonlocal fracture criteria are proposed, which are the development of the average stress criterion, and point stress criterion, and which contain a complex parameter that characterizes the size of the fracture process zone and accounts not only for the material microstructure, but also plastic properties of the material, geometry of the opening, and loading conditions. The calculation results are in good agreement with the resulting experimental data.
From placer deposits to technogenic mineral formations: resource and historical perspective (a study of Amur region)
Authors: Mirzekhanov Gadzhi , Mirzekhanova Zoia
Published: September 2020

Attention to mined gold placers as sources of mineral reserve base replenishment is constantly increasing. We conducted an analysis of the field mining ratio regarding the 170-year period of gold mining history in the region, which is roughly divided into four stages, using the example of gold placer clusters in the Amur region. Each stage has its own peculiarities that determine the nature and methods of alluvial deposits development and the amount of raw material losses. It’s shown that previously mined placers within the studied area are being developed continuously. The technogenic complex gets involved into operation almost immediately after mining the undeveloped placer. The obtained results confirm the fact that the indicator of demand for technogenic objects continuously increases with the upward trend from 64% during the first stage to 80% at present.
Comparative experiments on the activation cyanide and chloride re-leaching of gold from the secondary mineral material of heaps of Aprelkovo mine
Authors: Kirilchuk Maksim , Mustapha Adam
Published: September 2020

This article presents the results of comparative experiments on the activation chloride and activation carbonate-cyanide leaching of gold from the secondary mineral material of heaps of Aprelkovo mine. A cyanide scheme with a gradual increase in the cyanide concentration in the pregnant solution was adopted as a control scheme for percolation leaching. To establish the maximum recovery of gold and associated components, preliminary experiments with agitational cyanide leaching were carried out. In the course of the experimental work, some of the problems of gold recovery according to the classical cyanide scheme applicable to this deposit were identified and, thanks to the use of activated solutions, were solved. The reasons for the insufficiently high recovery are clogging and limited access of the complexing agent to encapsulated and chemically bound gold inclusions due to their high dispersion in the crystal lattices of concentrating minerals and the presence in the ore of minerals that tend to absorb water with a pronounced hydration effect.
Study of the prospects for expanding the range of collectors in the flotation of fluorite from technogenic raw materials
Authors: Voronova Olga , Kiyenko Lidia
Published: September 2020

The results of studies on the development of a technology for the extraction of fluorite concentrates from finely disseminated refractory technogenic raw materials from Primorsky deposits were presented. The account of the technological features of the stale tailings of the concentration plant of Yaroslavkaya Mining Company has been given. The necessity of fine grinding of the material and careful selection of reagent compositions providing the required flotation selectivity has been substantiated. The fundamental possibility of obtaining fluorite concentrates containing CaF2 up to 94% and more using several samples of collectors from the group of fatty acids has been established. Fatty acids of tall oil produced by Ust-Ilimsk timber processing complex and a mixture of fatty acids produced in India, branded MASOIL 1880, provide a sufficient level of flotation selectivity. The recovery of fluorite in an open enrichment cycle according to the scheme with seven cleanings of the foam product can be 61.85-63.84%.

The use of collectors compositions promotes an increase in the selectivity of the adsorption of reagents, which is accompanied by an increase in the selectivity of their action in comparison with the results obtained with the dosage of certain brands of the tested reagents into the flotation process. The extraction of fluorite into a concentrate obtained using a combination of tall oil and MASOIL-S fatty acids in a 1:1 ratio was 59.55-66.27% with a content of 95.6-94.23% CaF2 in it, respectively.
Research of combined reagent schemes of activation leaching of gold from oxidized ores of the Malmyzh field
Authors: Konareva Tatiana , Kirilchuk Maxim
Published: September 2020

The results of studies of the cyanide and an alternative methods for leaching gold and silver from oxidized ores of the Malmyzh field are presented. The possibility of recovering gold and silver from oxidized porphyry copper ores by thiosulfate solutions in agitation and percolation modes without intensifying the process – heating the solutions and adding copper ions – has been shown. Also, in a separate cycle – copper leaching with low-concentration sulfuric acid-sulfite solutions with additional opening of the silicate matrix with ammonium hydrofluoride – has been studied. The possibility of using ammonia-thiosulfate leaching in percolation mode has been investigated.
Theoretical basics of process of the dispersal system correction
Authors: Khrunina Natalia , Korneeva Svetlana
Published: September 2020

Factors analysis, determining the stability of mineral dispersal systems during disintegration was done. A mathematical model of the process of formation of small particles of the mineral component of hydromineral mixture in the field of hydrodynamic influence is presented, initiated by cavitation. The identified basic dependency options allowed, experimental studies of the disintegration of mineral particles, using electron microscopy to control the process and assess its effectiveness. Developed ideas about structural and mechanical features of mineral hydro-mineral mixture taking into account thermodynamic potential, the preconditions are not only theoretical justification for the process, but also the development of applied research in the development of technologies and means of processing and enrichment minerals in environmentally friendly ways.
Transport and economic problems of subsoil use in the Russian Far East
Authors: Arkhipova Yuliya , Bardal Anna
Published: September 2020

The Russian Far East possesses significant reserves of minerals. Mineral resources are rich in species diversity. The development of resources is faced with several problems, such as the depletion of active proven reserves in the exploited fields; high costs of transporting raw materials and finished products to processing sites or end-user markets; lack of availability of deposits; significant financial investments in the construction of new transport routes, etc. This means a transition from the extraction of raw materials to obtaining a product with a high stage of processing and the construction of transport routes. In this article, the authors examined the structure of investments in fixed assets by type of economic activity in the subjects of the Far Eastern Federal District. The values of the volumes of reserves and production of major minerals (for 2018) are presented, and resources are allocated based on which it is necessary to develop processing industries in the region. A comparison is made of the transport accessibility of options for locating a metallurgical plant in the Far East. The conclusion about the need for state support of resource projects and the development of measures to improve the conditions for investment has been substantiated.