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Mania is characterized by affective and cognitive alterations, with heightened external and self-awareness that are opposite to the alteration of awareness during epileptic seizures. Electrical stimulations carried out routinely during stereotactic intracerebral EEG (SEEG) recordings for presurgical evaluation of epilepsy may represent a unique opportunity to study the pathophysiology of such complex emotional-behavioral phenomenon, particularly difficult to reproduce in experimental setting. We investigated SEEG signals-based functional connectivity between different brain regions involved in emotions and in consciousness processing during a manic state induced by electrical stimulation in a patient with drug-resistant focal epilepsy. The stimulation inducing manic state and an asymptomatic stimulation of the same site, as well as a seizure with alteration of awareness (AOA) were analyzed. Functional connectivity analysis was performed by measuring interdependencies (nonlinear regression analysis based on the h2 coefficient) between broadband SEEG signals and within typical sub-bands, before and after stimulation, or before and during the seizure with AOA, respectively. Stimulation of the right lateral prefrontal cortex induced a manic state lasting several hours. Its onset was associated with significant increase of broadband-signal functional coupling between the right hemispheric limbic nodes, the temporal pole and the claustrum, whereas significant decorrelation between the right lateral prefrontal and the anterior cingulate cortex was observed in theta-band. In contrast, ictal alteration of awareness was associated with increased broadband and sub-bands synchronization within and between the internal and external awareness networks, including the anterior and middle cingulate, the mesial and lateral prefrontal, the inferior parietal and the temporopolar cortex. Our data suggest the existence of network- and frequency-specific functional connectivity patterns during manic state. A transient desynchronization of theta activity between the external and internal awareness network hubs is likely to increase awareness, with potential therapeutic effect.

The main deposits of kimberlite ores located in the regions of Western Yakutia are enriched at the ALROSA diamond extraction factories using a similar technology, in which the maximum completeness of extraction and safety of diamond crystals is ensured by the stages of schemes. The bulk of diamond crystals is extracted in the processes of heavy medium, sticky and foam separation, the effectiveness of which is determined by the properties of diamonds, kimberlite minerals and the media separating them. The article presents the results of theoretical and experimental studies carried out by ICEMR RAS together with the largest universities in Russia, scientific and industrial enterprises of ALROSA. It is shown that the use of combined energy methods of destruction and removal of hydrophilizing formations on diamond crystals provides hydrophobization of their surface in the processes of sticky and foam separation. It has been established that the efficiency and economic indicators of the process of dense medium separation of diamond-containing raw materials are due to the stability of the technological properties of the weighting agent of the ferrosilicon medium and the suspension prepared on its basis. The method for modifying the corrosion resistance of ferrosilicon by nitriding its surface has been substantiated and tested. The proposed method makes it possible to create a protective shell on the surface of the granules, preventing their destruction upon contact with corrosive components of the water-air environment. Semi-industrial tests have established the possibility of increasing the extraction of diamonds into concentrates for sticky and foam separation by 4 and 5.2%, respectively. The results of laboratory tests have confirmed the possibility of reducing the corrosion rate of ferrosilicon by 5-6 times in the process of dense medium separation.

The solubility of molybdenum trioxide (MoO3(s)) in aqueous solutions has been investigated experimentally at 250°, 300°, and 350°C and saturated water vapor pressure, and total Na concentrations ranging from 0 to 3 molal (m). Results of these experiments show that the solubility of MoO3(s) increases with increasing temperature and at 350°C can reach several thousand parts per million at high salinity (>1 m NaCl). At low Na+ activity, MoO3(s) dissolves dominantly as HMoO4,− whereas at high Na+ activity, the dominant species is NaHMoO40. The two dissolution reactions are MoO3(s)+H2O=HMoO4−+H+(1) and MoO3(s)+H2O+Na+=NaHMoO40+H+.(2) The values of the logarithms of the equilibrium constants for reaction (1) are –5.20 ± 0.12, –5.31 ± 0.17, and –5.50 ± 0.09 at 250°, 300°, and 350°C, respectively, and for reaction (2) the values are –3.40 ± 0.11, –3.25 ± 0.19, and –2.97 ± 0.09 for the same temperatures. In combination, these equilibrium constants yield equilibrium constants for the reaction relating the two aqueous species: Na++HMoO4−=NaHMoO40.(3) The values of the logarithms of the equilibrium constants for reaction (3) are 1.80 ± 0.16, 2.06 ± 0.25, and 2.53 ± 0.13 at 250°, 300°, and 350°C, respectively. Calculations, based on the results of this study and thermodynamic data available for other species, suggest strongly that in ore-forming hydrothermal systems, molybdenum is transported mainly as NaHMoO40 and deposits as molybdenite in response to cooling and possibly a reduction in fO2.

The solubility of tungsten trioxide solid and the speciation of tungsten in NaCl-bearing solutions have been investigated through experiments conducted at 250, 300, and 350 °C under vapour-saturated water pressure. Based on the results of these experiments, the solubility of tungsten trioxide was controlled by temperature and pH, whereas the NaCl concentration did not affect the solubility except through its influence on the ionic strength of the solution. Two tungsten species were found to be present in the solutions, namely H2WO40 at low pH and HWO4− at higher pH. These two species formed via the reactions WO3 + H2O = H2WO40 and WO3 + H2O = HWO4− + H+, respectively. The logarithms of the equilibrium constants for these reactions are −5.18 ± 0.26, −4.97 ± 0.25, −4.69 ± 0.10, and −7.91 ± 0.30, −7.67 ± 0.29, −7.52 ± 0.18 for 250, 300, and 350 °C, respectively. In addition, the logarithms of the first and second association constants of H2WO40 were determined to be 2.72, 2.71, 2.83, and 5.59, 6.49, 8.07 for 250, 300, and 350 °C, respectively. These values indicate that H2WO40 is only important at low pH values (

The paper discusses a way to improve the reliability design of the air pressure control system electric drive in the cockpit by electric drive components failure mode and effects analysis in the design development process. Possible options for the system's electric drive implementation have been investigated in terms of their reliability indicators. Components are selected, the failures of which have the greatest impact on the electric drive design reliability. The electric drive improved design is proposed.

The paper discusses a combined method of analysis the reliability indicators based on functional-cost analysis and failure modes and effects analysis, used to optimize the aviation electromechanical systems reliability indicators. Approaches to provide failure modes and effects analysis and functional-cost analysis of aviation electromechanical systems components, taking into account the implementing cost of each function, and their implementation results examples are shown. The proposed method description, its main parameters, as well as its approbation on the example of the developed aircraft fuel pump electromechanical drive: the control unit and the electric motor are given. A failure cost level index is proposed. It allows to estimate the cost of inputs of eliminating a functional failure, taking into account its occurrence probability. The reliability and cost characteristics of developed electromechanical drive are calculated. The components with the highest failure cost level index are identified, and recommendations are given on possible ways to improve the reliability of these components.

The article considers a method of error-correcting coding based on the holographic representation of a digital signal. The message encoding process is a mathematical simulation of a hologram created in virtual space by a wave from an input signal source. The code word is a hologram of a point, it is also a one-dimensional zone ruler that carries information about the input data block in the form of an n-bit code of the coordinate of the center of the Fresnel zones. It is shown that the holographic representation of the signal has significantly greater noise immunity and allows you to restore the original digital combination when most of the code message is lost and when the encoded signal is distorted by noise several times higher than the signal level. To assess the noise immunity, the reliability of information transmission over the channel with additive white Gaussian noise is compared using the Reed-Solomon code, the Reed-Muller code, the majority code, and the holographic code. The comparative efficiency of codes in the presence of packet errors caused by the effect of fading due to multipath propagation in radio channels is considered. It is shown that holographic coding provides the correction of packet errors regardless of the length of the packet and its location in the codeword. The holographic code is of interest for transmitting information over channels with a low signal-to-noise ratio (space communications and optical communication systems using free space as a transmission channel, terrestrial, including mobile radio communications), as well as for storing information in systems exposed to ionizing radiation.

The necessity of taking into account influencing factors in determining the reliability of the object is shown. Given the assumptions adopted in the calculations for reliability. It is shown that valve motors are more reliable than induction motors and DC collector motors. The approach to calculating the reliability indicators and the influence of external factors on the failure rate of the valve motor with an electronic control unit.

Large or long objects require measuring systems as a combination of more than one measuring instrument. In this case, the combination of instruments is a network system consists of several measuring modules and one central module. Measuring modules make the preliminary computation of measuring information and translate it to the central module for the final computation of measuring parameters. The central module also makes statistics of measuring and archive of information. Some tasks require the noncontact methods of measuring angular and linear coordinates of objects or places. The Central module can perform two-stage processing of measurement information. In the first stage, the Central measuring module performs a preliminary configuration of the distributed measuring system based on the information received from GPS sensors. The second stage is to use the measuring information received from the peripheral modules based on optical-electronic measurement methods. Using two-stage processing can significantly improve the efficiency of a distributed measurement system. The optoelectronic measuring devices (OEMD) are ideal for these purposes. These devices also have other advantages like great precision, calibration, and adaptation. In this article variants of the distributed measuring systems are described. The basic attention is given to the description of the unified optoelectronic modules for the measurement of angular and linear coordinates.

The behavior of uranium in environments, ranging from those of natural systems responsible for the formation of uranium deposits to those of nuclear reactors providing 11% of the world’s electricity, is governed by processes involving high-temperature aqueous solutions. It has been well documented that uranium is mobile in aqueous solutions in its oxidized, U6+ state, whereas in its reduced, U4+ state, uranium has been assumed to be immobile. Here, we present experimental evidence from high temperature (>100 °C) acidic brines that invalidates this assumption. Our experiments have identified a new uranium chloride species (UCl4°) that is more stable under reducing than oxidized conditions. These results indicate that uranium is mobile under reducing conditions and necessitate a re-evaluation of the mobility of uranium, particularly in ore deposit models involving this metal. Regardless of the scenario considered, reducing conditions can no longer be considered a guarantee of uranium immobility., Ore deposits and nuclear reactors are greatly affected by the solubility and speciation of uranium at elevated (>100 °C) temperature. Here, the authors identify a new uranium chloride species (UCl40), which is mobile under reducing conditions, thereby necessitating a re-evaluation of uranium mobility.

Subject of Research.The paper considers parameters relations in active reference mark optical-electronic system of large-sized structures spatial position control in the presence of vertical temperature gradient. We describe the idea and operation principle of the dispersion method forthe vertical temperature gradient determination bycolor camera and RGB optical radiation source. The basic condition for choosing parameters of active reference mark optical-electronic system is derived from relations that define hardware realization of the system and parameters of the air tract, which are used in the dispersion method. Method. The principle of equal influence of error components on the totalerror is used. We admitted an assumption that optical radiation is propagating in the single "refractive block" and there is no fluctuations of the air tract refractive index in time and space.Main Results.The basic criterion is proposed for choosing parameters of active reference mark optical-electronic system for large-sized structuresspatial position control in thepresence of vertical temperature gradient. The efficiency of the dispersion method for minimization of vertical temperature gradient influence is proved. The basic condition proposed gives the possibilityto estimate this efficiency and choose the hardware parameters.Practical Relevance.The results given in the paper can be used in design of active reference mark optical-electronic systems where the influence of the air tract is strong.

The speciation of U in NaCl-bearing solutions at temperatures up to 250 °C and concentrations of NaCl up to 1.5 m has been investigated using an in situ spectroscopic technique. The recorded spectra permit us to identify the species present in the solutions as UO22+, UO2Cl+, and UO2Cl2°. UO2Cl3− is also likely present at high temperatures and NaCl concentrations, but concentrations of this species are insufficient for derivation of the formation constants. No evidence was found for species of higher ligand (Cl−) number. Thermodynamic stability constants derived for these species show fair agreement with published data for 25 °C, but differ significantly from those predicted by an earlier high-temperature study (Dargent et al., 2013), which suggested that UO2Cl42− and UO2Cl53− contribute significantly to the mass balance of uranyl chloride complexes, especially at high temperature. In contrast, our data suggest that the main uranyl-chloride complex present in aqueous solutions at T > 150 °C and concentrations of NaCl relevant to natural hydrothermal systems is UO2Cl2°. The values of the logarithms of thermodynamic formation constants (β) for the reaction UO22+ + Cl− = UO2Cl+ are 0.02, 0.25, 0.55, 1.09, 1.59, and 2.28 derived at 25, 50, 100, 150, 200, and 250 °C, respectively. For the reaction UO22+ + 2Cl− = UO2Cl2° the values of log β derived at these temperatures are 0.4, 0.58, 0.74, 1.44, 2.18, and 3.42. Values of the formation constant estimated for uranyl-chloride species predict the high concentrations of U observed by Richard et al. (2011) in fluid inclusions of the giant McArthur River unconformity-type uranium deposit.

Introduction Stereo-electroencephalography (SEEG) is an invasive procedure, used to identify the epileptogenic zone that can be surgically removed in order to treat drug-resistant epilepsy. Frameless robot-assisted positioning of depth electrodes permits a 3D approach with different obliquities and trajectories. The objective of the present study was to evaluate the morbidity and the accuracy related to this frameless procedure. Patients and methods Sixty-six patients were managed wherein 901 electrodes were implanted during a 6-year-period. All patients had a postoperative CT-scan that was fused with preoperative MRI planning. In order to assess the accuracy of the procedure, the Euclidian distance was calculated between the coordinates of the planned trajectory and the actual position of the electrode at the entry point and at the target point for 857 electrodes. Results Among the 66 patients, one (1.5%) experienced a symptomatic brain haematoma and one (1.5%) a stroke-like migraine after radiation therapy (SMART) syndrome. There was no permanent morbidity or mortality. Compared to the classical SEEG approach, a higher rate of asymptomatic postoperative bleeding was found on the CT-scan in 8 patients (12.1%). Any infectious events were recorded. The median accuracy of frameless robotic SEEG procedure was equivalent to a 1.1 mm error deviation (0.15–2.48) at the entry point and 2.09 mm (1.06–3.72) at the target point respectively, with no differences for double obliquity trajectories. Conclusion Frameless robot-assisted SEEG appears to be a safe procedure, providing sufficient accuracy in order to delineate the epileptogenic zone and represents a helpful tool in the pre-surgical management of refractory epilepsy.

The management of antithrombotic therapy (AT) after surgery for chronic subdural hematoma (cSDH) requires taking account of the balance of risk between hemorrhage recurrence (HR) and the prophylactic thromboembolic effect (TE). The goal of the present study was to evaluate the prevalence of vascular events (VE: TE and/or HR) in the first 3 postoperative months after cSDH evacuation in patients previously treated by AT. The impact of AT resumption was also evaluated.This observational prospective multicenter collaborative study (14 French neurosurgery centers) included patients with cSDH treated by AT and operated on between May 2017 and March 2018. Data collection used an e-CRF, and was principally based on an admission questionnaire and outcome/progression at 3 months.In this cohort of 211 patients, VE occurred in 58 patients (27.5%): HR in 47 (22.3%), TE in 17 (8%), with mixed event in 6 cases (2%). Median overall time to onset of complications 26 days±31.5, and specifically 43.5 days±29.25 for HR. Non-resumption of AT significantly increased the relative risk of VE [OR: 4.14; 95% CI: 2.08 - 8.56; P0.001] and especially of TE [OR: 7.5; 95% CI: 1.2 - 42; P0.001]. The relative risk of HR was significantly increased when AT was resumed at less than 30 days (P=0.015).The occurrence of VE in patients operated on for cSDH and previously treated by AT was statistically significant (27.5%). HR was the most common event (22.3%), whereas TE accounted for only the 8%, although with shorter time to onset. In order to prevent TE risk, AT should be restarted after 30 days, as HR risk is greatly decreased beyond this time.

The article deals with theoretical aspects of CMOS sensor cross-links effect as a main drawback of the dispersion method implementation with CMOS video camera and RGB optical radiation source. The paper is concerned with usage of diffraction grating to solve the problem of images overlapping on CMOS sensor with Bayer pattern. It is shown that the diffraction distribution allows to determine the energy centers of different images of the same RGB optical radiation source independently at the same time without overlapping. The text gives mathematical description of how diffraction image is formed and how to use it in dispersion method. The article is of interest to people who deals with optical radiation propagation through the air tract with vertical temperature gradient.

The usage of the innovative primary converters requires the development of new methods and algorithms of relay protection and automation, including the fault location algorithms taking into account the features of these primary converters and digital current and voltage transformers at all. The developed algorithm is applied to conduct the estimation of the distance to a fault (short circuit point) using one-sided measurement of emergency mode parameters. The authors provide the results of the research on the influence of the distorting factors on the fault location accuracy conducted on the simulation models. The special program in MATLAB was developed for the research of numerous distorting factors and conducting a large number of experiments.

Digital current and voltage transformers are designed to large-scale transformation of voltage, alternating and/or direct current. Then they transmit the results of transformation to electricity metering systems, devices for measuring, relay protection, automatics, alarm, and control. There was developed the remote fault location method using data (instantaneous values of primary quantities) from innovative current and voltage sensors, which are included in the digital transformer structure. The results of the research of algorithm performance in cases of the influence of different distorting factors are presented.

The article describes the method of error-correcting coding based on the holographic representation of the digital signal. The coding process of a code message is a mathematical modeling of a hologram generated in virtual space by a wave from an input source. It is shown that the holographic representation of the signal has significantly greater noise immunity and allows you to restore the original digital combination when the majority of the code message is lost and when the encoded signal is distorted by noise that exceeds the signal level several times. The achieved level of noise immunity is determined by the level of redundancy. For example, with a redundancy factor of q=32, error-free decoding of the signal occurs when a 70% of the signal is lost, while with a redundancy factor of q=512, the loss of the signal can reach 90%.

The combination of engineering geodesy methods with computer processing of digital images on the matrix field of analysis has found wide application in various automatic systems for monitoring the mutual spatial position of elements. The use of stereoscopic schemes allows to control the spatial position of the railway track relative to the brands placed on the supports of the contact network. When moving along the path in such schemes, additional errors arise due to blurring on the photo-receiving matrix fields. The article discusses the methodology for estimating additional errors due to the movement of the stereoscopic optical-electronic system relative to fixed reference marks. Ways to reduce additional errors from the speed of movement by adaptive control of the size of the input apertures and the exposure time of images on photo-receiving matrix fields are proposed.

The article describes the general models, the basic principles of work and features of the construction of the photometric unit. Various factors affecting the photometric module are described. A method for measuring the overall energy calculation of the optical system of a photometric module has been proposed. Research has been conducted to develop methods for determining the sensitivity characteristics of a photomultiplier, finding ways to reduce the impact of the photomultiplier’s sensitivity non-uniformity on the area when diamonds are detected. As a result of experimental studies, dependences were obtained from which it can be concluded that the photomultiplier’s sensitivity non-uniformity affects the process of extracting diamond-containing ore.

Hypothalamic hamartomas (HH) are rare congenital malformations located in the region of the tuber cinereum and third ventricle. Their usual clinical presentation is characterized by gelastic/dacrystic seizures which often become pharmaco-resistant and progress to secondary focal/generalized intractable epilepsy causing mostly in children cognitive and behavioral problems (particularly in cases of progressive epileptic encephalopathy) and precocious puberty. Whereas gelastic seizures can be surgically controlled either by resection of the lesion or disconnection (tissue-destructive) procedures, aimed at functionally prevent the spreading of the epileptic burst; generalized seizures tend to respond better to HH excision rather than isolated neocortical resections, which generally fail to control them. Prospective analysis of 14 consecutive patients harboring HH treated in an 8-year period; 12 patients had unilateral and two bilateral HH. All patients were managed by pure endoscopic excision of the HH. The mean operative time was 48 min and mean hospital stay was 2 days; perioperative blood loss was negligible in all cases. Two patients showed a transient diabetes insipidus (DI); no transient or permanent postoperative neurological deficit or memory impairment was recorded. Complete HH excision was achieved in 10/14 patients. At a mean follow-up of 48 months, no wound infection, meningitis, postoperative hydrocephalus, and/or mortality were recorded in this series of patients. Eight patients became seizure free (Engel class I), 2 other experienced worthwhile improvement of disabling seizures (Engel class II); 2 patients were cured from gelastic attacks while still experiencing focal dyscognitive seizures; and 2, having bilateral HH (both undergoing unilateral HH excision), did not experience significant improvement and required later on a temporal lobectomy coupled to amygdalohyppocampectomy. Overall, the followings resulted to be predictive factors for better outcomes in terms of seizure control: (1) cases of unilateral, Delalande class B, HH, (2) shorter history of epilepsy. Endoscopic resection of HH proved, in our series, to be effective in achieving complete control or in reducing the frequency of seizures. Furthermore, this approach has confirmed its minimally invasive nature with a very low morbidity rate: of note, it allowed to better preserve short-term memory and hypothalamic function.

The solubility of Nb2O5 and the speciation of niobium in HF-bearing aqueous solutions have been determined at temperatures of 150, 200, and 250 °C and saturated water pressure. At a pH of ∼2 and at low HF concentration, niobium is transported primarily as the species Nb(OH)4+ and at high HF concentration, as the species NbF2(OH)3°. Equilibrium constants for the formation of Nb(OH)4+ range from −11.23 ± 0.26 to −10.86 ± 0.24 and for the formation of NbF2(OH)3° from −3.84 ± 0.20 to −5.08 ± 0.42, at 150 and 250 °C. The results of this study show that the solubility of Nb2O5 (solid) in aqueous fluids increases with increasing HF concentration, but is not strongly affected by temperature. The influence of pH is variable; at low pH and HF concentration, a decrease in pH increases the solubility of Nb2O5 (solid). At higher pH, the reverse may be true. Modeling of the transport and deposition of niobium suggests that simple mixing with a brine is not an effective method for removing niobium from solution. By contrast, interaction of an acidic fluid with carbonate rock results in a rapid reduction in the capacity of the fluid to mobilize niobium.

Overhead high-voltage power lines are the longest and quite often damaged parts of an energy system. A line outage is always accompanied by the undersupply of energy, decreasing the reliability, cost and quality of electric supply. That is why one of the important tasks of line maintenance is a quick search for the location of damage and organization of the rehabilitation. The increase of the accuracy of automatic remote fault location (RFL) and development of new RFL methods including the methods of self-clearing fault location represent a current challenge. This article is devoted to the results of development and research of synchronized two-sided RFL method using signals from digital current and voltage transformers as input. The means of increasing its accuracy are considered.

Objective Epilepsy associated with periventricular nodular heterotopia (PNH) is characterized by complex relationships between the heterotopic and the normotopic cortex during the interictal state and at seizure onset. High-frequency oscillations (HFO) have been proposed as a marker of epileptogenicity that might reflect disease activity. The effects of thermocoagulations on epileptogenicity in this context remain unknown. We aimed to investigate the interictal HFO- and spike profiles of different cortical structures before and after two consecutive SEEG-guided thermocoagulations, in correlation with seizure outcome, in a patient with PNH-related drug-resistant epilepsy. Methods The epileptogenic zone (EZ) was defined by SEEG analysis based on the Epileptogenicity Index. Interictal spikes, ripples (80–250 Hz) and fast ripples (FR, 250-330 Hz) were analyzed within the heterotopia, the temporal neocortex and the hippocampus. Results The SEEG recordings revealed a distributed EZ involving the heterotopia and the posterior temporal neocortex. Both structures were targeted by thermocoagulations. Background spikes, ripples and FR-rates were significantly higher in PNH compared to the normotopic cortex. A drastic reduction of spikes (by over 80%) and absence of FR were demonstrated both in the PNH and in the neocortex during the second SEEG exploration 6 months after the first thermocoagulation, whereas no significant difference was observed in the posterior hippocampus. Ripples were significantly reduced by the first and suppressed by the second thermocoagulation within the three structures. Seizures relapsed after two months but decreased in frequency after the first thermocoagulation. Sustained seizure-freedom was achieved only after the second procedure. Conclusions Our data demonstrate the running down of interictal HFO and spikes within the epileptogenic network following thermocoagulations of heterotopic and normotopic sites involved at seizure onset. This dynamics was in good correlation with significantly improved seizure control. Significance Combination of ictal and different interictal markers of epileptogenicity, including HFO and spike analysis, is important to get the full picture of the epileptogenic zone and could help to evaluate the disease activity.

The high-voltage power lines are quite often the damaged parts of an energy system. The line outage is always accompanied by the undersupply of energy, decreased reliability, cost and quality of electric supply. That's why one of the important tasks of line maintenance is a quick location determination of the damage and organization of the rehabilitation. [1], [2]. There are wide-spreading methods and means of remote fault location on the power lines in power industry based on measurement of the emergency mode parameters (EMP). So, the main part of this paper includes the development and research of the methods and algorithms for fault location based on the one-sided measurement of EMP. This type of measurement uses the signals from digital current and voltage transformers as input ones [3]–[5].

The behavior of niobium and tantalum is poorly understood in rocks that have undergone significant hydrothermal alteration, and niobium-tantalum minerals of hydrothermal origin are rarely mentioned in the literature. Consequently, the mobility of these critical metals, although widely considered to be negligible, has not been evaluated. In this paper, we present the results of a study of the genesis of niobium and tantalum mineralization in the Nechalacho rare metal deposit, Northwest Territories, Canada, which contains one of the largest known resources of these metals in rocks that have undergone intense hydrothermal alteration. Analyses and examination of samples using the electron microprobe has led to the identification of a variety of niobium- and tantalum-bearing minerals in the Nechalacho deposit. Niobium-bearing zircon, columbite-(Fe), fergusonite-(Y), and samarskite-(Y) were identified in the ore zones of the deposit, uranopyrochlore, and columbite-(Fe) were found outside the ore zones, and magmatic fluornatropyrochlore was shown to be the sole niobium-tantalum mineral in relatively unaltered syenites below the Basal ore zone. Based on the paragenetic relationships among the above minerals, variations in the composition of the columbite group minerals as a function of location in the Nechalacho Layered Suite and the distribution of niobium, tantalum, zirconium, and uranium in the bulk rocks, we have developed a model to explain the occurrence of niobium and tantalum in the Nechalacho deposit. The first step in the concentration of these elements was the crystallization of niobium- and tantalum-bearing zircon and eudialyte in the subhorizontal Upper and Basal ore zones, respectively. This was accompanied by the crystallization of magmatic columbite-(Fe) in the Upper ore zone. Fergusonite-(Y) crystallized in the Basal ore zone and also formed due to the breakdown of eudialyte. Outside the ore zones, there was crystallization of pyrochlore and to a lesser extent magmatic columbite-(Fe). This step led to the development of strong spatial associations among niobium, zirconium, and uranium that are evident as strong positive correlations in the bulk-rock concentrations of these elements at the meter scale. During the ensuing intense and widespread hydrothermal alteration, niobium was locally remobilized. Hydrothermal columbite-(Fe) and fergusonite-(Y) formed at the cores of altered zircon grains. Wholesale replacement of magmatic columbite-(Fe) and fergusonite-(Y) by hydrothermal anhedral crystals occurred in the two ore zones. The estimated relative proportions of the sources of these minerals in the ore zones, although varying to some extent because of a dependence on the amount of niobium mobilized from zircon, is ~40/60. Outside the ore zones, columbite-(Fe) and uranopyrochlore are the present manifestations of the former pyrochlore. With the exception of magmatic fluornatropyrochlore in the fresher syenites below the Basal ore zone and a single example of magmatic columbite-(Fe) in an Upper ore zone sample, all niobium and tantalum minerals have a hydrothermal origin as a result of this pervasive alteration.

Nowadays, there are two main methods to realize three-dimensional non-scanning laser imaging detection, which are detection method based on APD and detection method based on Streak Tube. However, the detection method based on APD possesses some disadvantages, such as small number of pixels, big pixel interval and complex supporting circuit. The detection method based on Streak Tube possesses some disadvantages, such as big volume, bad reliability and high cost. In order to resolve the above questions, this paper proposes an improved three-dimensional non-scanning laser imaging system based on Digital Micromirror Device. In this imaging system, accurate control of laser beams and compact design of imaging structure are realized by several quarter-wave plates and a polarizing beam splitter. The remapping fiber optics is used to sample the image plane of receiving optical lens, and transform the image into line light resource, which can realize the non-scanning imaging principle. The Digital Micromirror Device is used to convert laser pulses from temporal domain to spatial domain. The CCD with strong sensitivity is used to detect the final reflected laser pulses. In this paper, we also use an algorithm which is used to simulate this improved laser imaging system. In the last, the simulated imaging experiment demonstrates that this improved laser imaging system can realize three-dimensional non-scanning laser imaging detection.

The research of the possibility of the dispersion method sensitivity increase for the air tract vertical temperature gradient determination by analyzing the diffraction pattern is provided. It is invited to analyze the diffraction pattern forming by the two-wavelength optical radiation from the single source. It is invited to evaluate the increase in linear difference between the energy centers coordinates of the same image but in different spectral zones.

Despite the numerous industrial and scientific applications of gallium, its behavior in nature and the processes that concentrate it to potentially economic levels are poorly understood. Although the main supply of this metal is as a by-product of the mining of bauxite, it is also concentrated by magmatic-hydrothermal processes in peralkaline igneous systems. Here we report the results of a study of the distribution of gallium and the controls on this distribution in the Nechalacho rare metal deposit, Northwest Territories, Canada, which has been shown to contain significant reserves of this critical metal. Electron microprobe analyses and X-ray element maps of gallium-bearing minerals were used to determine the mineralogical distribution of gallium in the Nechalacho intrusive suite. Elevated gallium concentrations were identified in albite, biotite, orthoclase, chlorite, and allanite. Of these aluminum-bearing minerals, the most important hosts of gallium are albite, biotite, and orthoclase. Ferric iron-bearing minerals, including magnetite and aegirine, which were considered potential candidates for gallium sequestration, contain relatively low concentrations of the metal. This behavior of gallium, at least from a magmatic perspective, is consistent with its predicted partitioning between phenocrysts and melt. However, there is also evidence that gallium was redistributed by hydrothermal fluids. Chloritization of biotite resulted in the enrichment of gallium in the secondary mineral (chlorite), and the development of secondary albite (albitization) led to a depletion of gallium in primary albite. On the basis of these results, we argue that the overall distribution of gallium within the Nechalacho deposit was controlled by magmatic crystal fractionation, whereas hydrothermal processes led to local remobilization of the metal. During fractional crystallization, gallium was moderately compatible in minerals such as albite and biotite, whereas it bordered between compatibility and incompatibility in minerals such as magnetite and orthoclase, and was incompatible in aegirine. This resulted in a relatively constant bulk gallium concentration in the Nechalacho deposit, although locally, gallium was remobilized hydrothermally, particularly within the most altered parts of the intrusion, notably, the albitite.

The research of the influence of the LED radiation brightness distribution on the energy sensitivity of optical-electronic systems with optical equal zone is provided. Mathematical modeling of the radiation field on a matrix receiver, considering lens spherical aberration, is provided. The possibility of forming a uniform illumination on the photo-detector matrix, changing the shape of the distribution of the brightness of the LED at a predetermined invariable spherical aberration of the lens is provided.

The paper analyzes the construction matters and metrological parameters of the electrooptic converter to control linear displacements of the large structures of the buildings and facilities. The converter includes the base module, the processing module and a set of the reference marks. The base module is the main unit of the system, it includes the receiving optical system and the CMOS photodetector array that realizes the instrument coordinate system that controls the mark coordinates in the space. The methods of the frame-to-frame difference, adaptive threshold filtration, binarization and objects search by the tied areas to detect the marks against accidental contrast background is the basis of the algorithm. The entire algorithm is performed during one image reading stage and is based on the FPGA. The developed and manufactured converter experimental model was tested in laboratory conditions at the metrological bench at the distance between the base module and the mark 50±0.2 m. The static characteristic was read during the experiment of the reference mark displacement at the pitch of 5 mm in the horizontal and vertical directions for the displacement range 400 mm. The converter experimental model error not exceeding ±0.5 mm was obtained in the result of the experiment.

Introduction Le stroke like migraine after radiation therapy (SMART) syndrome associe cephalees, troubles neurologiques aigus, crises epileptiques et prise de contraste corticale a l’IRM, a distance d’une radiotherapie cerebrale. Observation Un patient droitier de 42 ans (no 1974278), aux antecedents de migraines et de lesion gliale parietale droite non etiquetee a ete traitee en 2002 par radiotherapie et chimiotherapie adjuvante dans l’hypothese d’une lesion de haut grade. Dix ans plus tard, le patient developpe une epilepsie focale pharmacoresistante d’origine structurelle suspectee mais avec des atypies motivant une exploration invasive par video-stereo-electro-encephalographie (SEEG) dans une demarche pre-chirurgicale. Quarante-huit heures apres l’implantation des electrodes profondes, le patient presente des cephalees, un deficit sensitivo-moteur du membre superieur gauche, une heminegligence, un ralentissement psycho-moteur et des crises focales a semiologie electro-clinique inhabituelle. Les electrodes sont explantees en urgence et une IRM cerebrale est realisee qui montre un oedeme cortical massif et une prise de contraste corticale des regions centro-parietales, temporales et insulaires droites, avec augmentation du coefficient apparent de diffusion. Dans l’hypothese d’un SMART syndrome et devant la persistance de crises refractaires au traitement anticonvulsif, une corticotherapie intraveineuse a fortes doses a ete mise en place avec une regression complete du tableau clinico-radiographique en 72 h. Discussion Le SMART syndrome est une complication rare, retardee et presque toujours reversible, de la radiotherapie des tumeurs cerebrales. Les hypotheses physiopathologiques sont (i) une vasculopathie reversible ou (ii) une atteinte neuronale avec alteration du systeme trigemino-vasculaire ou baisse du seuil pour la depression corticale envahissante. Le plus souvent spontane, un SMART syndrome peut rarement etre induit par une chirurgie tumorale. Conclusion A notre connaissance, le SMART syndrome survenant lors d’une exploration SEEG n’a jamais ete decrit. Le rapport benefice-risque doit etre pris en compte avant un geste neurochirurgical en cas d’antecedent de radiotherapie.

The article describes the possibilities of using the non-traditional current and voltage sensors to solve the problem of fault location in terms of digital transformers developed at the Ivanovo State Power Engineering University (ISPEU). Frequency and metrological characteristics of current and voltage sensors are given.