bluuebunny/crossref_metadata_2025 huggingface dataset:
Kualitas Fisik Amoniasi Fermentasi (AMOFER) Janggel Jagung dengan Penambahan M21 Dekomposer pada Level yang Berbeda
Authors: Fitria Restuti , Candrasari Dewi Puspita
Published: September 2019

Pemanfaatan limbah hasil pertanian, perkebunan dan agroindustri dapat dilakukan dalam rangkamengatasi permasalahan ketersediaan pakan ternak ruminansia. Salah satu limbah pertanian yang memilikipotensi besar untuk diolah menjadi pakan adalah janggel jagung. Janggel jagung dapat digunakan sebagai pengganti sumber serat karena kandungan serat kasarnya yang tinggi. Namun, kandungan protein dan kecernaan janggel jagung rendah sehingga perlu dilakukan upaya untuk meningkatkan kualitas janggel jagung sebagai bahan pakan yaitu amoniasi dan fermentasi. Tujuan penelitian ini untuk mengevaluasi level penambahan M21 dekomposer terhadap kualitas fisik amoniasi fermentasi janggel jagung. Penelitian dilaksanakan menggunakan metode eksperimental dengan Rancangan Acak Lengkap (RAL). Perlakuan dalam penelitian ini adalah penambahan M21 dekomposer atau aras starter komersial (0; 0,02 ; 0,04; 0,06% dari total larutan formula). Variabel yang diamati meliputi warna, bau/aroma, tekstur dan ada atautidaknya pertumbuhan jamur. Data yang diperoleh kemudian diolah secara deskriptif. Hasil diketahui bahwa perlakuan menyebabkan perubahan warna menjadi coklat, bau/aroma menjadi asam dan tercium bau amonia, tekstur pada janggel jagung menjadi lebih lunak serta tidak adanya   pertumbuhan jamur. Perubahan kualitas fisik tersebut dapat disimpulkan bahwa perlakuan mampu meningkatkan kualitas fisik janggel jagung.Kata Kunci: Janggel Jagung, Amoniasi, Fermentasi, Kualitas Fisik
Pengaruh Force Molting terhadap Produksi Telur Tetas dan Fertilitas Induk Ayam Broiler
Authors: Hartati Ratna , Wijayanti Dwi
Published: September 2019

Penelitian ini bertujuan untuk mengkaji tentang produksi telur tetas, fertilitas telur dan bobot badan induk ayam broiler pasca Force Molting dan korelasi antara ketiga parameter tersebut terhadap output yang dihasilkan. Penelitian ini dilaksanakan di PT. Super Unggas Jaya, Desa Cikembar, Kecamatan Cikembar, Kabupaten Sukabumi, Jawa Barat pada bulan Juni hingga November 2019. Parameter yang diamati dalam penelitian ini yaitu produksi telur, fertilitas telur dan bobot hidup ayam pasca force molting. Berdasarkan hasil penelitian dapat disimpulkan bahwa penerapan teknologi force molting pada induk ayam broiler dapat meningkatkan produksi telur tetas. Angka fertilitas yang dihasilkan cukup baik, namun harus ada optimalisasi jumlah ayam pejantan untuk mengoptimalkan fertilitas pada telur tetas yang dihasilkan.Kata Kunci : Induk Ayam Broiler, Force Molting, Produksi, Fertilitas
UJI AKTIVITAS PERTUMBUHAN RAMBUT KOMBINASI EKSTRAK ETANOL DAUN PANDAN WANGI (Pandanus amaryllifolius Roxb.) DAN DAUN LIDAH MERTUA (Sansevieria trifasciata Prain.)
Authors: Agustien Gina Septiani
Published: September 2019

ABSTRACT The frequency and quantity of hair loss problems increases which eventually leads to baldness. The use of medicinal plants today is very popular and increasingly favored by the community. Plants are efficacious as a hair grower such as pandanus leaves (Pandanus amaryllifolius Roxb.) and sansevieria leaves (Sansevieria trifasciata Prain.). The purpose of this study to determine the hair growth activity of a combination of pandanus leaves extract and sansevieria leaves. Test preparation was made by combining both extracts at 5% concentration with comparison of pandanus leaves extract and sansevieria leaves 1: 1, 2: 3 and 3: 2. The results showed that the combination of 3: 2 has the best hair growth activity. Testing of this hair growth activity is a combination extract compared to normal control, 96% ethanol and minoxidil. The result of hair growth activity showed that the combination extract had better activity than the sole extract. Key word : hair growth activity, pandanus leaves, sansevieria leaves, extract combination.
Azologization and repurposing of a hetero-stilbene-based kinase inhibitor: towards the design of photoswitchable sirtuin inhibitors
Authors: Grathwol Christoph W , Wössner Nathalie , Swyter Sören , Smith Adam C , Tapavicza Enrico , Hofstetter Robert K , Bodtke Anja , Jung Manfred , Link Andreas
Published: September 2019

The use of light as an external trigger to change ligand shape and as a result its bioactivity, allows the probing of pharmacologically relevant systems with spatiotemporal resolution. A hetero-stilbene lead resulting from the screening of a compound that was originally designed as kinase inhibitor served as a starting point for the design of photoswitchable sirtuin inhibitors. Because the original stilbenoid structure exerted unfavourable photochemical characteristics it was remodelled to its heteroarylic diazeno analogue. By this intramolecular azologization, the shape of the molecule was left unaltered, whereas the photoswitching ability was improved. As anticipated, the highly analogous compound showed similar activity in its thermodynamically stable stretched-out (E)-form. Irradiation of this isomer triggers isomerisation to the long-lived (Z)-configuration with a bent geometry causing a considerably shorter end‐to‐end distance. The resulting affinity shifts are intended to enable real‐time photomodulation of sirtuins in vitro.
A Catalog of Hyper-luminous X-Ray Sources and Intermediate-mass Black Hole Candidates out to High Redshifts
Authors: Barrows R. Scott , Mezcua Mar , Comerford Julia M.
Published: September 2019

Hyper-luminous X-ray sources (HLXs; L
X > 1041 erg s−1) are off-nuclear X-ray sources in galaxies and strong candidates for intermediate-mass black holes (IMBHs). We have constructed a sample of 169 HLX candidates by combining X-ray detections from the Chandra Source Catalog (Version 2) with galaxies from the Sloan Digital Sky Survey and registering individual images for improved relative astrometric accuracy. The spatial resolution of Chandra allows for the sample to extend out to z ∼ 0.9. Optical counterparts are detected among one-fourth of the sample, one-third of which are consistent with dwarf galaxy stellar masses. The average intrinsic X-ray spectral slope indicates efficient accretion, potentially driven by galaxy mergers, and the column densities suggest one-third of the sample has significant X-ray absorption. We find that 144 of the HLX candidates have X-ray emission that is significantly in excess of the expected contribution from star formation and hot gas, strongly suggesting that they are produced by accretion onto black holes more massive than stars. After correcting for an average background or foreground contamination rate of 8%, we estimate that at least ∼20 of the HLX candidates are consistent with IMBH masses, and this estimate is potentially several times higher assuming more efficient accretion. This catalog currently represents the largest sample of uniformly selected, off-nuclear IMBH candidates. These sources may represent scenarios in which a low-mass galaxy hosting an IMBH has merged with a more massive galaxy and provide an excellent sample for testing models of low-mass BH formation and merger-driven growth.
Distances to Galactic OB Stars: Photometry versus Parallax
Authors: Shull J. Michael , Danforth Charles W.
Published: September 2019

For application to surveys of interstellar matter and Galactic structure, we compute new spectrophotometric distances to 139 OB stars frequently used as background targets for UV spectroscopy. Many of these stars have updated spectral types and digital photometry with reddening corrections from the Galactic O-Star (GOS) spectroscopic survey. We compare our new photometric distances to values used in previous International Ultraviolet Explorer and Far Ultraviolet Spectroscopic Explorer surveys and to parallax distances derived from Gaia-DR2, after applying a standard (0.03 mas) offset from the quasar celestial reference frame. We find substantial differences between photometric and parallax distances at d > 1.5 kpc, with increasing dispersion when parallax errors exceed 8%. Differences from previous surveys arise from new GOS stellar classifications, especially luminosity classes, and from reddening corrections. We apply our methods to two OB associations. For Perseus OB1 (nine O stars) we find mean distances of 2.47 ± 0.57 kpc (Gaia parallax) and 2.99 ± 0.14 kpc (photometric) using a standard grid of absolute magnitudes. For 29 O stars in Car OB1 associated with Trumpler 16, Trumpler 14, Trumpler 15, and Collinder 228 star clusters, we find 2.87 ± 0.73 kpc (Gaia) and 2.60 ± 0.28 kpc (photometric). Using an alternative grid of O-star absolute magnitudes shifts these photometric distances ∼7% closer. Improving the distances to OB stars will require attention to spectral types, photometry, reddening, binarity, and the grid of absolute magnitudes. We anticipate that future measurements in Gaia-DR3 will improve the precision of distances to massive star-forming regions in the Milky Way.
On the Use of Field RR Lyrae as Galactic Probes. I. The Oosterhoff Dichotomy Based on Fundamental Variables*
Authors: Fabrizio M. , Bono G. , Braga V. F. , Magurno D. , Marinoni S. , Marrese P. M. , Ferraro I. , Fiorentino G. , Giuffrida G. , Iannicola G. , Monelli M. , Altavilla G. , Chaboyer B. , Dall’Ora M. , Gilligan C. K. , Layden A. , Marengo M. , Nonino M. , Preston G. W. , Sesar B. , Sneden C. , Valenti E. , Thévenin F. , Zoccali E.
Published: September 2019

We collected a large data set of field RR Lyrae stars (RRLs) by using catalogs already available in the literature and Gaia DR2. We estimated the iron abundances for a subsample of 2382 fundamental RRLs (ΔS method: Ca ii K, Hβ, Hγ, and Hδ lines) for which there are publicly available medium-resolution SDSS-SEGUE spectra. We also included similar estimates available in the literature, ending up with the largest and most homogeneous spectroscopic data set ever collected for RRLs (2903). The metallicity scale was validated by using iron abundances based on high-resolution spectra for a fundamental field RRL (V Ind), for which we collected X-shooter spectra covering the entire pulsation cycle. The peak ([Fe/H] = −1.59 ± 0.01) and the standard deviation (σ = 0.43 dex) of the metallicity distribution agree quite well with similar estimates available in the literature. The current measurements disclose a well-defined metal-rich tail approaching solar iron abundance. The spectroscopic sample plotted in the Bailey diagram (period versus luminosity amplitude) shows a steady variation when moving from the metal-poor ([Fe/H] = −3.0/–2.5) to the metal-rich ([Fe/H] = −0.5/0.0) regime. The smooth transition in the peak of the period distribution as a function of the metallicity strongly indicates that the long-standing problem of the Oosterhoff dichotomy among Galactic globular clusters is the consequence of the lack of metal-intermediate clusters hosting RRLs. We also found that the luminosity amplitude, in contrast with period, does not show a solid correlation with metallicity. This suggests that period–amplitude–metallicity relations should be cautiously treated.
Low Star Formation Efficiency in Typical Galaxies at z = 5–6
Authors: Pavesi Riccardo , Riechers Dominik A. , Faisst Andreas L. , Stacey Gordon J. , Capak Peter L.
Published: September 2019

Using the Very Large Array and ALMA, we have obtained CO(2–1), [C ii], and [N ii] line emission and multiple dust continuum measurements in a sample of “normal” galaxies at z = 5–6. We report the highest-redshift detection of low-J CO emission from a Lyman break galaxy, at z ∼ 5.7. The CO line luminosity implies a massive molecular gas reservoir of (1.3 ± 0.3)(α
CO/4.5 M
⊙ (K km s−1 pc2)−1) × 1011
M
⊙, suggesting low star formation efficiency with a gas depletion timescale of order ∼1 Gyr. This efficiency is much lower than traditionally observed in z ≳ 5 starbursts, indicating that star-forming conditions in main-sequence galaxies at z ∼ 6 may be comparable to those of normal galaxies probed up to z ∼ 3 to date but with rising gas fractions across the entire redshift range. We also obtain a deep CO upper limit for a main-sequence galaxy at z ∼ 5.3 with an approximately three times lower star formation rate, perhaps implying a high α
CO conversion factor, as typically found in low-metallicity galaxies. For a sample including both CO targets, we also find faint [N ii] 205 μm emission relative to [C ii] in all but the most IR-luminous “normal” galaxies at z = 5–6, implying more intense or harder radiation fields in the ionized gas relative to lower redshift. These radiation properties suggest that low metallicity may be common in typical ∼1010
M
⊙ galaxies at z = 5–6. While a fraction of main-sequence star formation in the first billion yr may take place in conditions not dissimilar to lower redshift, lower metallicity may affect the remainder of the population.
The Roles of Mass and Environment in the Quenching of Galaxies
Authors: Contini E. , Gu Q. , Kang X. , Rhee J. , Yi S. K.
Published: September 2019

We study the roles of stellar mass and environment in quenching the star formation activity of a large set of simulated galaxies by taking advantage of an analytic model coupled to the merger tree extracted from an N-body simulation. The analytic model has been set to match the evolution of the global stellar mass function since redshift z ∼ 2.3 and give reasonable predictions of the star formation history of galaxies at the same time. We find that stellar mass and environment play different roles: the star formation rate/specific star formation rate–M
* relations are independent of the environment (defined as the halo mass) at any redshift probed, 0 < z < 1.5, for both star-forming and quiescent galaxies, while the star formation rate–M
halo relation strongly depends on stellar mass in the same redshift range, for both star-forming and quiescent galaxies. Moreover, the star formation rate and the specific star formation rate are strongly dependent on stellar mass even when the distance from the cluster core is used as a proxy for the environment, rather than the halo mass. We then conclude that stellar mass is the main driver of galaxy quenching at any redshift probed in this study, not just at z > 1 as generally claimed, while the environment has a minimal role. All the physical processes linked to the environment must act on very short timescales, such that they do not influence the star formation of active galaxies, but increase the probability of a given galaxy to become quiescent.
The spiders (Arachnida: Araneae) community of an agroecosystem
Authors: Dentici Antonino , La Mantia Tommaso
Published: September 2019

The agricultural areas, especialy the orchards, of more ancient cultivation, are characterized by having plant and animal communities of great interest. Plant and vertebrate communities are well studied in theese agroecosystems, but the same cannot be said for invertebrates. Among these are generally known taxonomic groups of agricultural interest, including also beetles (Coleoptera) and moths (Lepidoptera). Little known are other arthropods such as those belonging to the Arachnida. In a historic orchard of the Conca d'Oro, the plain around Palermo city, systematic observations and catches of Arachnidae have been conducted, with particular interest in spiders (Araneae) but also involving other orders such as Opiliones and Pseudoscorpionida. The surveys showed a great species richness. It is in fact a historic orchard characterized by the presence of numerous species of fruit trees (Citrus spp., Loquat Eriobotrya japonica, etc.) interspersed with small vegetable garden surfaces. Many of the individuals found are in the process of being determined, but it is so far the community is exceeding sixty species. The research is ongoing and will further aim to clarify the ecological relationships between the different species and the other components of the agro-ecosystem.
Changes in land cover and grassland area over the past 120 years in a rapidly urbanised area in Japan
Authors: Noda Akira , Kondoh Akihiko , Nishihiro Jun
Published: September 2019

In wet temperate regions, human activity has played an important role in shaping the size and distribution of grasslands. We examined change in land cover type and grassland area in a 9.2 × 22.3 km area of northern Chiba Prefecture, based on historical maps and documents for four time periods (1880s, 1950s, 1980s and 2000s). In the 1880s, conifer forests occupied the largest area (43.1%) amongst land cover types and grasslands accounted for 4.2% of the total area. However, literature available from the 1880s suggests that the understorey of conifer forests may have served as additional habitat for grasses. Thus, the habitat of grassland species is suggested to have covered up to 54% of the study area during this time period. By the 1950s, much of the grassland present in the 1880s had been changed to agricultural fields and paddies and grassland area had reduced to 2.9%. Residential development prior to and during the 1980s led to the conversion of forests and agricultural fields to grassland, increasing the grassland area to 11.6% of the study area. Finally, in the 2000s, grasslands had declined to 6.0% of the study area, likely due to conversion to residential areas. Despite these changes over time, 1.5% of the study area has remained as native forest or grassland for over 120 years. The spatial data presented herein are useful for conservation planning and studying the effect of historical land use change on biodiversity.
Taxonomic novelties in Amaryllidaceae from the Department of Ancash, Peru, and a new combination in Clinanthus
Authors: Meerow Alan W. , Cano Asunción
Published: September 2019

Clinanthus inflatus (Amaryllidaceae) and Ismene parviflora are described from Ancash Department in Peru. The flower of C. inflatus is urceolate, and resembles that of Urceolina (Amaryllidaceae tr. Eucharideae), a unique morphology for the genus. Ismene parviflora, with its small, loosely formed, narrowly funnelform-tubular perigone with a ventricose limb, appears to have some affinity to subgen. Pseudostenomesson and may represent an intermediate form between the former and species of subgen. Ismene. Stenomesson rubrum is transferred to Clinanthus as C. ruber on the basis of its narrowly lorate leaf morphology.
Association between blood omega-3 polyunsaturated fatty acids and the gut microbiota among breast cancer survivors
Authors: Horigome A. , Okubo R. , Hamazaki K. , Kinoshita T. , Katsumata N. , Uezono Y. , Xiao J.Z. , Matsuoka Y.J.
Published: September 2019

Omega-3 polyunsaturated fatty acids (PUFAs) are essential nutrients demonstrated to have health benefits, such as decreasing the risk of coronary heart disease, improving parameters associated with metabolic syndrome, and decreasing anxiety symptoms and depression risk. Previous intervention studies indicated the association between blood or tissue PUFA levels and the gut microbiota; however, the details remain incompletely elucidated. We conducted a cross-sectional study to examine the association between PUFAs and the gut microbiota among breast cancer survivors. Adults who had been diagnosed with invasive breast cancer more than one year ago and were not currently undergoing chemotherapy were enrolled. Capillary blood and faecal samples were obtained to assess the blood PUFA levels and gut microbiota compositions. The mean age (n=124) was 58.7 years, and 46% of the participants had a history of chemotherapy. Multiple regression analysis controlling for possible confounders indicated that an increased relative abundance ofActinobacteriawas significantly associated with increased levels of docosahexaenoic acid (DHA, beta=0.304, q<0.01). At the genus level, the abundance ofBifidobacteriumwas positively associated with the level of DHA (beta=0.307, q<0.01). No significant association between omega-6 PUFAs and the relative abundances of gut microbiota members was observed. In addition, analyses stratified by the history of chemotherapy indicated significant associations of PUFA levels with the abundance of some bacterial taxa, including the phylumActinobacteria(DHA, beta=0.365, q<0.01) andBacteroidetes(EPA, beta=-0.339, q<0.01) and the genusBifidobacterium(DHA, beta=0.368, q<0.01) only among participants without a history of chemotherapy. These findings provide the first evidence of positive associations between the abundances ofBifidobacteriumamong the gut microbiota and the levels of omega-3 PUFAs in the blood. Further studies are required to gain additional insight into these associations in healthy subjects as well as into the causality of the relationship.
Creatine-kinase reference intervals at rest and after maximal exercise in Standardbred racehorses
Authors: Stucchi L. , Valli C. , Stancari G. , Zucca E. , Ferrucci F.
Published: September 2019

Due to the high variability of data drawn from the literature, aim of the study was to evaluate the effects of exercise on creatine-kinase (CK) serum activity and to determine CK reference intervals (RIs) at rest and post-exercise in healthy Standardbred racehorses. Data concerning history, physical examination, laboratory evaluation and ECG were collected retrospectively from a population of 258 Standardbred racehorses in training that underwent an incremental-maximal treadmill exercise. Those subjects with alterations potentially influencing CK serum activity were excluded. Finally, a reference sample of 194 horses was selected. Blood samples were collected 1 hour before exercise and 6 hour post-exercise and analysed with a spectrophotometric method. Values were compared by Wilcoxon test for paired samples. The effect of age and sex was evaluated by Kruskal-Wallis and Dunn post-test. Statistical significance was set atP<0.05. RIs were determined following Clinical and Laboratory Standard Institute guidelines (CLSI), approved by the American Society for Veterinary Clinical Pathology. Using a macroinstruction set for Microsoft Excel (RefValAdv), RIs were determined with a non-parametric method. A significant increase (P<0.0001) in CK activity post-exercise was observed. Partition by sex and age did not show any statistical difference, either at rest or post-exercise. In RIs determination no outliers were identified. RIs ranged from 25 to 394 U/l at rest and from 44 to 735 U/l post-exercise. To our knowledge, this is the first study considering CK post-exercise RIs in racehorses using CLSI’s guidelines and specific CK-related exclusion criteria. These RIs could be useful to discriminate between physiological and pathological CK post-exercise increase.
Necrotizing Conjunctival Ulceration Following Subconjunctival Depot Methylprednisolone Injection
Authors: Zamir Ehud , Pe'er Jacob
Published: September 2019

Abstract. To report the occurrence of a necrotizing conjunctival ulcer at the site of methylprednisolone injection. A 35-year-old woman underwent a routine extracapsular cataract extraction. Subconjunctival methylprednisolone acetate (Depo-Medrol, Pharmacia & Upjohn, Kalamazoo, MI) was injected at the end of the operation. A necrotizing conjunctival ulcer developed at the site of injection. Necrotic tissue and remnants of the drug were excised, and the conjunctiva healed within 10 days. Postoperative subconjunctival injection of methylprednisolone may cause necrosis and ulceration of the overlying conjunctiva. Subconjunctival and subtenon corticosteroid injections are commonly used in various inflammatory ocular conditions and prophylactically after intraocular operations. We describe a case of conjunctival necrosis at the site of injection, an adverse effect that has been previously reported in only 1 case in the ophthalmological literature. [Ophthalmic Surg Lasers 1999;30:565-566.]
Estudio microtomográfico de la anatomía de Laubieriopsis cabiochi (Amoureux, 1982) (Annelida, Fauveliopsidae)
Authors: Parapar Julio , Permuy Iria , Candás María , Cunha-Veira Xela , Zamora José Luis , Moreira Juan
Published: September 2019

La Microtomografía Computarizada (micro-CT o μCT) es una técnica de estudio microestructural, no destructiva, que permite estudiar la anatomía interna y externa de muestras biológicas, y realizar su reconstrucción a través de un modelo virtual en tres dimensiones. En los últimos años esta técnica está aportando avances significativos en el conocimiento anatómico de diversos invertebrados marinos. En este trabajo se estudia la anatomía externa e interna de Laubieriopsis cabiochi (Amoureux, 1982) (Annelida, Fauveliopsidae) y paralelamente se valora la calidad de las imágenes de μCT frente a las obtenidas en estudios previos mediante métodos histológicos clásicos.
Los isópodos terrestres de Galicia, España (Crustacea: Isopoda, Oniscidea)
Authors: Cifuentes Julio
Published: September 2019

La revisión de la colección de Isopoda del Museo Nacional de Ciencias Naturales de Madrid (MNCN) y la del autor, ha permitido estudiar 431 ejemplares de 19 especies de isópodos terrestres de Galicia, España. Una especie se cita por la primera vez para Pontevedra y Galicia, Tylos europaeus Arcangeli, 1938, y Porcellio herminiensis (Vandel, 1946) se cita por primera vez para la provincia de A Coruña. La fauna conocida de isópodos terrestres de Galicia está formada por 38 especies, 28 de ellas se encuentran en la provincia de Pontevedra, 24 especies en A Coruña, 15 especies en Orense y 14 especies en Lugo.
Method of Text Content Development in Creation of Professionally Oriented Online Courses for Oil and Gas Specialists
Authors: Murzo Yuliya , Sveshnikova Svetlana , Chuvileva Natalia
Published: September 2019

The article analyzes the experience of text content development for an online course created for oil and gas professionals. The article features a critical review of the current situation in online systems of distance learning, establishes principles of creating professionally oriented language curricula, as well as requirements to the functionality of online platforms that enable creation of such courses and their delivery to the audience. The work provides a detailed analysis of text content development principles and criteria. It presents three stages of developing text content for the first module of a professionally oriented online course.
First African Female to Manage a Global Crisis
Authors: Guah Matthew Waritay
Published: September 2019

Many studies have looked at leadership during disasters and emergencies in a number of countries but hardly any has concentrated on developing countries and the implications of these nations' infrastructure, culture, and control systems. This chapter attempts to examine the leadership of Mrs. Ellen Johnson-Sirleaf, the first female president on the African continent, who led a global medical epidemic response during Liberia's recent Ebola crises. It identifies lessons to be learned by future leaders of developing countries as well as executives of non-governmental organizations frequently working on disaster relief projects around the globe.
Optimization of Welding Parameters for Small-Scale Resistance Spot Welding of Zirconium Alloys
Authors: Slobodyan Mikhail S. , Kiselev Aleksey S.
Published: September 2019

This paper presents the results of optimization of parameters for resistance spot welding of parts made of E110 zirconium alloy with a thickness of 0.25 + 0.25 mm. Its purpose was to determine the influence of welding current profiles on nugget metal structure and mechanical properties of welds. The highest tensile strength comparable with base metal (380...440 MPa) was observed when the ratio of integral heat input to current pulse duration was about two. Formation of martensitic structure and coarsening of nugget metal was observed with larger ratios. A proper fusion zone was not formed with lower ratios. Annealing of welded joints at a pressure of ~ 10–4 Pa and a temperature of 580 °C for one hour was necessary to reduce residual stresses and transformation of metastable martensitic phase to a more stable state. This reduced microhardness of nugget metal by 30...35% and increased tensile strength of welds. It was also possible to increase tensile strength and reduce dispersion of its values by increasing duration of current down slope after formation of a nugget. An increase in duration from 1 to 14 ms caused rise in tensile strength by ~ 18% and dispersion of its values by ~ 3%.
Strain Stress Model of the Rail with Crack in its Head and Estimation of its Operational Lifetime
Authors: Muravev Vitaliy V. , Tapkov Kirill A. , Volkova Ludmila V. , Platunov Andrei V.
Published: September 2019

The most common reason of the fatigue crack appearance is the presence of stresses in the rail. The process of stress strain state simulation for the R65 rail is presented in the paper. Values of residual stresses were modeled and chosen to be maximum allowed by GOST (State Standard): -77 MPa in the rail head, -125 MPa in the web and 106 MPa in rail foot. These stresses match the value-77 MPa measured by the acoustoelastic method from the center of the rolling surface of the rail. The influence of the crack at the highest level of the stress strain state was studied in cases of the maximum train load and its absence. According to results of modeling, stresses in the sharp edge of the crack can exceed the lowest acceptable by GOST (State Standard) value of the yield strength by more than 5 times in case of the presence of the train load. In case of the absence of the train load, the crack does not have a significant influence on the stress strain state. The modelling process was also used to study the influence of the installation temperature difference on the operational lifetime of the rail. The paper presents the description of the influence between the installation temperature difference and the crack initiation. According to modeling results and the rail defect catalogue, rails with the lowest acceptable mechanical characteristics are prohibited to be used after 300∙109kg and higher tonnage.
Analysis of the Possibility of Determining the Internal Structure of Oil and Gas Pipes by CT Method
Authors: Osipov Sergei P. , Chakhlov Sergei , Shan Jiang , Kairalapov Daniyar
Published: September 2019

A mathematical model has been developed to simulate the initial projections for computed tomography of large-sized oil and gas pipes and to transform the projections into the mass thickness distributions. The simulated projections of steel pipes with a diameter from 530 mm to 1420 mm are given with variation of ADC capacity and the number of photons incident on the front surface of the multichannel bremsstrahlung detector. The necessity of correct selection of these parameters is proved. A possibility to estimate the density distribution over a pipe cross section based on the inverse Abel transform for the fan-beam of bremsstrahlung is illustrated. The issues related to the technical feasibility of the computed tomography method for inspecting of large-sized pipes and concerning the estimation of the total scan time and the choice of ADC capacity are considered. Recommendations on the adjustment of the analog and digital signals ranges are given. The obtained results make it possible to evaluate the feasibility of designing a computer tomography system for monitoring large-sized oil and gas pipes.
A Simple Method for Colorimetric and Naked-Eye Detection of Mercury in Fish Products
Authors: Saranchina Nadezhda V. , Dudkina Anna A. , Gavrilenko Maria M. , Gavrilenko Nataliya A.
Published: September 2019

A new colorimetric optode has been developed for preconcentration and visual determination of mercury ions in fish products. This optode is based on the color reaction of copper diethyldithiocarbamate with Hg2+ in the body of polymethylmethacrylate matrix. The optode exhibited sensitivity through the change of color from brown to colorless, which could be easily detected by naked-eye or spectrophotometric method. The influence of acidity, contact time and interference of foreign metal ions has been studied. The optode revealed good linearity in the range of 20-360 μg·L-1, with a limit of detection of 8 μg·L-1 Hg2+ at pH 5.2 and response time of 10 min.
Effects of Electrode Degradation on Properties of Small-Scale Resistance Spot Welded Joints of E110 Alloy
Authors: Kiselev Aleksey S. , Slobodyan Mikhail S.
Published: September 2019

Effect of electrode degradation on stability of nugget formation during small-scale resistance spot welding is presented in this paper. Production of spacer grids for nuclear fuel assemblies made of E110 zirconium alloy cells of 0.25 mm thickness was studied. The following degradation processes took place in the electrodes as they wore. Roughness of the tip surface was gradually reduced to the values of the welded cells. The semispherical tips were severely deformed during the initial period of their operation (1.500...2.000 welds). The deformation dynamics slowed down significantly after that. Microhardness on the tip surface of the electrodes decreased. It was minimal in the central part of the surface layer with a thickness of 50...100 μm and increased towards the periphery. Significant coarsening of the electrode metal microstructure occurred at a depth of ~ 1 mm. Nugget area and its tensile strength decreased as the electrodes wore. An increase in welding current did not reduce deterioration of nugget quality. Measurement and processing of dynamic resistance between electrodes did not make it impossible to predict and control the properties of nuggets for the studied welding modes.
Method of Processing Data of Acoustic Array
Authors: Shulgina Yuliya , Kostina Maria A. , Shulgin Evgeniy , Soldatov Alexey
Published: September 2019

Within this article, a method has been developed to reduce the amount of transmitted data from the receiving and preprocessing unit to a personal computer. On logical grounds, there is compelling reason to use as a basic property of an ellipse as a ground of the method. The developed data processing algorithm for the multi-element array system was tested in the MatLab software package. Also, a block diagram and data processing algorithm were developed for the practical implementation on a field programmable gate array.
Solid-Phase Formation of Li-Zn Ferrite under High-Energy Impact
Authors: Nikolaev Evgeniy , Lysenko Elena , Surzhikov Anatoly P.
Published: September 2019

The effect of complex high-energy action, including mechanical milling of Li2CO3-Fe2O3-ZnO initial reagents mixture and its consistent heating by the pulsed electron beam on solid-phase synthesis was studied by X-ray powder diffraction and thermal analyses. The initial mixture Li2CO3-Fe2O3-ZnO corresponds to the ferrite with stoichiometric formula: Li0.5(1–x)ZnxFe2.5–0.5xО4, where х = 0.2. The same studies were carried out with thermal heating in a laboratory furnace for detection the effect of radiation on the formation of phase composition lithium-zinc ferrite. Initial mixture was milled in AGO-2S planetary ball mill with a milling speed of 2220 rpm for 60 min. Radiation-thermal synthesis of the milled mixture was carried out by the pulsed electron accelerator (ILU-6) at 600°C and 750°C. The maximum time of the isothermal stage was 60 minutes. According to the X-ray powder diffraction and thermogravimetric analysis, it was found that the complex high-energy action leads to decrease a temperature and time of obtaining lithium-zinc ferrite homogeneous in phase composition. The proposed high-energy regimes allow to synthesized lithium-zinc ferrites at 600 °C for 60 minutes, which is much lower compared to conventional ceramic technology.
The Eddy Current Method of Alloy Drill Pipes Wall Thickness Evaluation: Impact Analysis
Authors: Goldshtein Aleksandr E. , Belyankov Vasily Y.
Published: September 2019

The dependences of the surface eddy current probe added voltage at the interaction of the probe magnetic field with an aluminum pipe from the following main interference factors are determined: the pipe wall thickness, the gap between the probe and the surface of the pipe, the electrical conductivity of the material, the curvature of the pipe wall, the presence of areas with a smooth thickness change of the wedge character and a local spherical thinning, axis misalignment with respect to the pipe surface, the lateral misalignment of the probe axis. The problem is solved with the help of the finite element method (FEM). These data are consistent with the experimental results.
The Influence of the Magnetic Field on the Current-Voltage Characteristics of CuPc Nanowires
Authors: Zavgorodniy Alexey , Aimukhanov Aitbek , Zeinidenov Assylbek , Vavilova Galina
Published: September 2019

The role of spin states in the process of charge carrier transport in copper phthalocyanine (CuPc) nanowires has been established. According to the data obtained, CuPc nanowires are in the η-phase. The current-voltage characteristics (IVC) of a photosensitive cell based on CuPc nanowires in a magnetic field are investigated. As a result of experiments, it was found that applying an external magnetic field, the spins of two positively charged polarons are oriented in one direction. The channel of formation of the bipolaron is blocked. As a result, a decrease in the short-circuit current of the photosensitive cell is observed by more than 61%.
miR-301a Regulates Inflammatory Response to Japanese Encephalitis Virus Infection via Suppression of NKRF Activity
Authors: Hazra Bibhabasu , Chakraborty Surajit , Bhaskar Meenakshi , Mukherjee Sriparna , Mahadevan Anita , Basu Anirban
Published: September 2019

Microglia being the resident macrophage of brain provides neuroprotection following diverse microbial infections. Japanese encephalitis virus (JEV) invades the CNS, resulting in neuroinflammation, which turns the neuroprotective role of microglia detrimental as characterized by increased microglial activation and neuronal death. Several host factors, including microRNAs, play vital roles in regulating virus-induced inflammation. In the current study, we demonstrate that the expression of miR-301a is increased in JEV-infected microglial cells and human brain. Overexpression of miR-301a augments the JEV-induced inflammatory response, whereas inhibition of miR-301a completely reverses the effects. Mechanistically, NF-κB–repressing factor (NKRF) functioning as inhibitor of NF-κB activation is identified as a potential target of miR-301a in JEV infection. Consequently, miR-301a–mediated inhibition of NKRF enhances nuclear translocation of NF-κB, which, in turn, resulted in amplified inflammatory response. Conversely, NKRF overexpression in miR-301a–inhibited condition restores nuclear accumulation of NF-κB to a basal level. We also observed that JEV infection induces classical activation (M1) of microglia that drives the production of proinflammatory cytokines while suppressing alternative activation (M2) that could serve to dampen the inflammatory response. Furthermore, in vivo neutralization of miR-301a in mouse brain restores NKRF expression, thereby reducing inflammatory response, microglial activation, and neuronal apoptosis. Thus, our study suggests that the JEV-induced expression of miR-301a positively regulates inflammatory response by suppressing NKRF production, which might be targeted to manage viral-induced neuroinflammation.
Glucocorticoids Oppose Thymocyte Negative Selection by Inhibiting Helios and Nur77
Authors: Mittelstadt Paul R. , Taves Matthew D. , Ashwell Jonathan D.
Published: September 2019

Glucocorticoid (GC) signaling in thymocytes shapes the TCR repertoire by antagonizing thymocyte negative selection. The transcription factors Nur77 and Helios, which are upregulated in TCR-signaled thymocytes, have been implicated in negative selection. In this study, we found that GCs inhibited Helios and, to a lesser extent, Nur77 upregulation in TCR-stimulated mouse thymocytes. Inhibition was increased by GC preincubation, and reductions in mRNA were prevented by a protein synthesis inhibitor, suggesting that GCs suppress indirectly via an intermediary factor. Upregulation of Helios in TCR-stimulated thymocytes was unaffected by deletion of Nur77, indicating Nur77 and Helios are regulated independently. Whereas CD4+ thymocytes are positively selected in wild-type AND TCR-transgenic B6 mice, loss of GC receptor expression resulted in increased negative selection. Correspondingly, Helios and Nur77 levels were elevated in TCRhiCD4+CD8+ (TCR-signaled) thymocytes. Notably, deletion of Helios fully reversed this negative selection, whereas deletion of Nur77 had no effect on CD4+CD8+ cell numbers but reversed the loss of mature CD4+ thymocytes. Thus, Nur77 and Helios are GC targets that play nonredundant roles in setting the signaling threshold for thymocyte negative selection.
CareD: Non-Pharmacological Assistance for Dementia Patients
Authors: Siddiq Kainat , Bawany Narmeen , Qamar Tehreem , Naveed Ayesha , Arif Bisma , Usman Mariam , Jamal Mehek
Published: September 2019

BACKGROUND: Dementia is a common form of Alzheimer disease which is affecting the quality of older adults’ life. Non-drug treatment such as cognitive therapies are more beneficial for such patients. These days, mobile applications are providing tremendous opportunities for aiding the medicinal treatment.OBJECTIVES: This paper presents CareD – a mobile application based solution for dementia patients and their caregivers. Unlike, other available mobile applications, CareD provide a single resolution for maximum dementia related complications. The main objective of this application is to improve the quality of life of dementia patients and facilitate their caregivers. CareD also aims at providing native language support i.e. Urdu to the people of Pakistan.METHODS: CareD comprises of various modules including cognitive therapy sessions, patient tracking, reminders, healthy living to aid dementia patients in their everyday activities. Experimental study involving dementia patients and their caregivers has been carried out to evaluate the usability and effectiveness of this application.RESULTS: Twenty patients were included in the study. Results showed that CareD is very effective and helpful in decreasing the disease progression as well as in relieving the burden of caregivers.CONCLUSION: CareD has been found to be a useful and efficient solution for dementia patients. It was observed that utilization of mobile application was progressively successful in reducing the stress of both; patients and their caregivers. The use of native language Urdu made the application more learnable for older adults and improved its acceptance.
Conformally related Kähler metrics and the holonomy of lcK manifolds
Authors: Madani Farid , Moroianu Andrei , Pilca Mihaela
Published: September 2019

A locally conformally Kähler (lcK) manifold is a complex manifold

(M,J)

together with a Hermitian metric

g

which is conformal to a Kähler metric in the neighbourhood of each point. In this paper we obtain three classification results in locally conformally Kähler geometry. The first one is the classification of conformal classes on compact manifolds containing two non-homothetic Kähler metrics. The second one is the classification of compact Einstein locally conformally Kähler manifolds. The third result is the classification of the possible (restricted) Riemannian holonomy groups of compact locally conformally Kähler manifolds. We show that every locally (but not globally) conformally Kähler compact manifold of dimension

2n

has holonomy

\mathrm{SO}(2n)

, unless it is Vaisman, in which case it has restricted holonomy

\mathrm{SO}(2n-1)

. We also show that the restricted holonomy of a proper globally conformally Kähler compact manifold of dimension

2n

is either

\mathrm{SO}(2n)

, or

\mathrm{SO}(2n-1)

, or

\mathrm{U}(n)

, and we give the complete description of the possible solutions in the last two cases.
Criticality theory for Schrödinger operators on graphs
Authors: Keller Matthias , Pinchover Yehuda , Pogorzelski Felix
Published: September 2019

We study Schrödinger operators given by positive quadratic forms on infinite graphs. From there, we develop a criticality theory for Schrödinger operators on general weighted graphs.
An uncertainty principle and lower bounds for the Dirichlet Laplacian on graphs
Authors: Lenz H. Daniel , Stollmann Peter , Stolz Günter
Published: September 2019

We prove a quantitative uncertainty principle at low energies for the Laplacian on fairly general weighted graphs with a uniform explicit control of the constants in terms of geometric quantities. A major step consists in establishing lower bounds for Dirichlet eigenvalues in terms of the geometry.
On Oblivion: the Case of Yugoslavian Monopoly
Authors: Pavšič Zala
Published: September 2019

This article on the Yugoslavian version of the board game Monopoly is based on the assumption that things make people. In accordance with this a concept, the contribution begins with a historical overview of the development of this game in the United States, from its origins when it spreads around the country as a popular game, to the current day, when Monopoly is marketed a leading corporation in the field of board games, Hasbro. The popularity of the game is also evident from its presence in the public space in the form of metaphors: because of its emphasis on trading, it is sometimes referred to “greed”, and in the Balkans it can also serve as a metaphor for the nation state.In the memories of my interlocutors who helped me with their testimonies, the Yugoslav version of Monopoly is associated with pleasant memories: especially of childhood, youth and relatives or friends with whom they used to play the game. In my interviews I focused on two topics which did not play such a significant role in the testimonies of the interlocutors, but were, however, common in the testimonies of interviewees who got acquainted with the game as children: to the question of the supposed superiority of Slovenia, as Bled and Bohinj were the most expensive properties, and the presumption that Monopoly is a game which can reproduce cultural memory, in this case knowing the geography of the former common state. The thesis on Slovene superiority proved to rely on generations to which my interviewees belonged, since it appeared especially in the answers of the interlocutors who were born in the late 1980s. Hence, I assume that this thesis was more likely a projection of the outside reality of my interlocutors into the game than vice versa.Analysing the answers of my interlocutors more thoroughly, I reached the conclusion that Monopoly often appeared as the first reference through which they heard about a certain resort in the regions of the former Yugoslavia. This means that Monopoly contained traces of cultural memory which other sources of our everyday lives, education and upbringing ceased to transmit.
The Oldest Japanese Picture Postcards in Today’s Slovenia
Authors: Shigemori Bučar Chikako
Published: September 2019

As a part of the research activities “East Asian Collections in Slovenia”, many old Japanese postcards have been identified in recent years. For the postcards archived in the National and University Library (NUK) in Ljubljana, no information was available in relation to their user or collector, when and from whom these postcards were acquired, etc. Out of 16 Japanese and Chinese postcards in the Library, seven have been actually used and sent with some messages from Japan or China to today’s Slovenia in the year 1899. During the research on other picture-postcards archived in today’s Slovenia, and in cooperation with specialists in Japanese Studies and the history of the modern era (end of the 19th and beginning of 20th centuries, the Meiji period in Japan) in the context of East Asian and Austro-Hungarian exchanges, it has gradually become clear who the user of the postcards was and in what setting. It was Jožef Obereigner, the second son of the caretaker of the Snežnik estate, who was an engineer and served in the Austro-Hungarian Navy.