Antimony and arsenic speciation in the major waste dump of the abandoned Lojane Sb-As-Cr mine, North Macedonia

<p>We present the results of mineralogical and geochemical investigations of the solid waste dump material from the abandoned Lojane mine in the northern part of North Macedonia. The geologically unusual Lojane deposit was mined for Sb (stibnite), As (realgar) and Cr (chromite) until 1979. Its waste dumps and tailings were left without any proper rehabilitation. Hence, it represents an extensive source of antimony and arsenic pollution.</p><p>In April 2018 we took samples from the major waste dump near Vaksince village. This 70 m long and 20 m wide, relatively ore-rich dump lies parallel to the creek bed of the immediately adjacent Suva creek (NW-SE). In 2017 a Turkish exploration company had dug a ~1.6 m deep trench along the middle of the elongate dump. The samples were taken along this trench using a hand-drill tool (ca. 20 cm deep) and laterally along the exposed profiles.</p><p>X-ray fluorescence (XRF) spectroscopy analyses showed that the mean concentrations of Sb and As are 9950 ppm and 32004 ppm, respectively, but can locally rise to extreme values of 24 g/kg for Sb and 200 g/kg for As. Besides Sb and As, very high amounts of Ni (up to 4672 ppm) and Cr (up to 5136 ppm) have been measured.</p><p>A combination of powder X-ray diffraction, Raman spectroscopy and SEM-EDS analyses (of polished aliquots) showed that the main primary source of antimony is stibnite with up to 2 at.% of As, while the main primary sources of arsenic are realgar, gersdorffite (up to 9 at.% of Sb) and As-rich pyrite (up to. 10 at.% of As). Additionally, minor amounts of Sb and As (up to 1.5 at.%) were detected in violarite (Fe<sup>2+</sup>Ni<sup>3+</sup><sub>2</sub>S<sub>4</sub>) and greigite (Fe<sup>2+</sup>Fe<sup>3+</sup><sub>2</sub>S<sub>4</sub>). Secondary phases of Sb and As are associated with amorphous iron oxyhydroxides (with up to 2 at.% Sb and up to 11 at.% As) and finely crystalline, porous and chemically inhomogeneous Ca-Fe-Sb-As-oxides/hydroxides belonging to the roméite group, with up to 7 at.% of As. Occasionally, dissolved Sb and As reprecipitated as senarmontite/valentinite, Sb<sub>2</sub>O<sub>3</sub>, scorodite, FeAsO<sub>4</sub>∙H<sub>2</sub>O (up to 2 at.% of Sb), annabergite, Ni<sub>3</sub>(AsO<sub>4</sub>)<sub>2</sub>∙8H<sub>2</sub>O, hörnesite, Mg<sub>3</sub>(AsO<sub>4</sub>)<sub>2</sub>∙8H<sub>2</sub>O, and arseniosiderite, Ca<sub>2</sub>Fe<sub>3</sub>(AsO<sub>4</sub>)<sub>3</sub>O<sub>2</sub>∙3H<sub>2</sub>O. These observations are in good agreement with our prior study focussing on the secondary mineralogy of this and other dumps (Kolitsch et al., 2018).</p><p>Further phases confirmed, in approximate order of decreasing abundance are: dolomite, serpentine group-minerals, magnesite, gypsum, quartz, talc, vermiculite, clay minerals, micas (muscovite, phlogopite, annite), plagioclase (albite, anorthite), calcite, siderite, chromite, magnesiochromite, spinel, magnetite, vaesite, clinochlore, tremolite, diopside, fluorapatite, rutile, zircon, monazite-(Ce), hydroxylapatite(?), hydroniumjarosite, chamosite, hematite, manganese oxyhydroxides, bornite, chalcopyrite, cobaltite, galena and baryte.</p><p>Financial support of the Austrian Science Fund (FWF) (P 30900-N28) is gratefully acknowledged.</p><p> </p><p>Kolitsch, U., Đorđević, T., Tasev, G., Serafimovski, T., Boev, I., Boev, B. (2018): Supergene mineralogy of the Lojane Sb-As-Cr deposit, Republic of Macedonia: Tracing the mobilization of toxic metals. Geol. Maced., 32, 95-117.</p>

FEATURES OF RESPONSIBILITY OF A MEDICAL ORGANIZATION FOR CAUSING THE PATIENT'S HEALTH

The article discusses the particular conditions of holding medical organizations accountable for causing harm to the health of patients. The conditions of civil liability, as well as the degree of responsibility of a medical organization in the provision of medical services, are analyzed. The authors are of the opinion that medical care should be organized in accordance with the procedures, conditions and standards for the provision of such care, however, the standards cannot cover all the options that may arise during the provision of medical care, therefore they are aimed at creating an average “sample”, to determine the approximate order of possible actions carried out by medical personnel. Attention is also paid to the consideration of the features of causing harm to the patient’s health, depending on whether the harm was caused in the provision of medical care or medical services. In conclusion, it was concluded that the conditions for bringing medical organizations to justice should include: unlawful action (inaction), harm, a causal relationship between unlawful action and harm, as well as the fault of the injurer.

Learning fine-grained estimation of physiological states from coarse-grained labels by distribution restoration

Due to its importance in clinical science, the estimation of physiological states (e.g., the severity of pathological tremor) has aroused growing interest in machine learning community. While the physiological state is a continuous variable, its continuity is lost when the physiological state is quantized into a few discrete classes during recording and labeling. The discreteness introduces misalignment between the true value and its label, meaning that these labels are unfortunately imprecise and coarse-grained. Most previous work did not consider the inaccuracy and directly utilized the coarse labels to train the machine learning algorithms, whose predictions are also coarse-grained. In this work, we propose to learn a precise, fine-grained estimation of physiological states using these coarse-grained ground truths. Established on mathematical rigorous proof, we utilize imprecise labels to restore the probabilistic distribution of precise labels in an approximate order-preserving fashion, then the deep neural network learns from this distribution and offers fine-grained estimation. We demonstrate the effectiveness of our approach in assessing the pathological tremor in Parkinson’s Disease and estimating the systolic blood pressure from bioelectrical signals.

Identifying verb collocational patterns in a specialized medical journal corpus

This paper examines the collocational patterns of frequent verbs in medical research articles, and proposes a way to help non-native speakers of English learn word combinations frequently used in specific professional genres. We explore the correlations in the syntactico-semantic behavior and the collocational patterns of related verbs, in order to systematically teach recurrent word combinations.To this end, we present a corpus-based analysis of the collocational patterning of the verbs which belong to the same semantic frame inFrameNet, the frame EVIDENCE. These verbs were identified in 397 medical research articles from a pre-release version of the PERC (Professional English Research Consortium) corpus (3,155,118 tokens and 115,960 word types). The verbs examined, in approximate order of degree of increasing certainty, aresuggest, argue, show, reveal, prove, demonstrate, substantiate, verify, confirmandcorroborate. The results reveal that verbs that can be grouped into semantic and syntactic coherent sets also share combinatorial properties. We conclude that, rather than studying isolated verbs, making learners aware of these patterns of verb groups can greatly contribute toward efficient learning of the language of professional texts.

A novel approach to approximate order preserving matching

Un problema importante en el análisis de mercado de valores y la recuperación de información musical es el emparejamiento con preservación de orden. Este problema es una variante recientemente introducida del problema de emparejamiento de cadenas en el que busca subcadenas en el texto cuya representación natural coincide con la representación natural del patrón. La representación natural de una cadena X es una cadena que contiene los rankings de los caracteres que ocurren en cada posición de X. Entonces, el emparejamiento con preservación de orden considera la estructura interna de las cadenas en lugar de sus valores absolutos. Pero tanto en el análisis de mercado de valores como en la recuperación de información musical, se requiere más flexibilidad: no sólo las subcadenas con exactamente la misma estructura son de interés, sino también las que son similares. En este artículo se propone una versión aproximada del problema de emparejamiento con preservación de orden basada en las distancias δγ que permiten un error individual entre el ranking de los símbolos correspondientes (delimitada por δ) y un error global de todas los rankings (delimitadas por γ). Se presenta un algoritmo que resuelve este problema en O(nm+m log m). Los resultados experimentales verifican la eficiencia del algoritmo propuesto.

Material Modeling of High-Pressure Compliant Syntactic Foams

Syntactic foam, specifically a host urethane embedded with hollow microspheres, has been shown to be an effective method to treat pressure pulsations, also known as noise, within a hydraulic system; however, the current generation of foam becomes less effective with increasing system pressure, particularly ineffective above 7 MPa. Material modeling predicts that increasing the initial internal pressure of a microsphere will allow voids within the foam to retain their size at pressures up to 35 MPa and the foam will remain compliant at those pressures. Noise is attenuated by an expansion chamber lined with syntactic foam when the system pressure causes embedded microspheres to collapse, which leaves a gaseous void within the host urethane, greatly reducing the effective bulk modulus of the foam. Predicted material properties are then used in conjunction with a previously developed linear acoustic model to predict the effectiveness of developmental syntactic foams. Changing the mechanical properties of the current host urethane does not have a drastic impact on the overall performance unless the properties have been reduced to the approximate order as the properties of the void. The factors with the most consequence on noise control effectiveness are the internal pressure of the microspheres and system pressure.