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Superconducting On-chip Fourier Transform Spectrometers (SOFTS) are broadband, compact and electronic interferometers. Being extremely compact, SOFTS can fit into standard antenna coupled detector architectures. SOFTS will enable kilo-pixel spectro-imaging focal planes enhancing sub-millimeter science; particularly cluster astrophysics / cosmology, CMB-science and line intensity mapping. This proceeding details the development, design and bench-marking of RF on-chip architecture of SOFTS for Ka and W bands.

The standard JK drop weight test breaks single particles at five size fractions each at different energy levels by dropping a given weight from a certain height. The progenies of all particles at a given energy level are sieved and the degree of breakage of all those particles at that energy level is presented as t10% (percent passing 1/10th of original size). This method assumes that all of the particles in a single size fraction have the same mass and experience a similar degree of breakage and calculates the average breakage characteristics of an ore domain from impact loading. Hence, this standard approach does not capture the breakage variability that exists among ore particles. To investigate the breakage variability of ore, the drop weight testing method has been extended where the energy applied and the degree of breakage for each particle within the sample are measured separately. Therefore, the degree of breakage for the ore domain is expressed as an envelope of t10% vs energy curves. This approach provides some insight into the intrinsic variability of the response to impact loading within an ore domain. Several rock types were tested by the extended DWT testing approach and the implications of ore breakage variability for a SAG mill treating these materials are simulated for a standard SAB circuit using the JKMRC grinding models.

Ground-based cosmic microwave background (CMB) experiments are undergoing a period of exponential growth. Current experiments are observing with 1000–10,000 detectors, and the next-generation experiment (CMB stage 4) is proposing to deploy approximately 500,000 detectors. This order of magnitude increase in detector count will require a new approach for readout electronics. We have developed superconducting resonators for next-generation frequency-domain multiplexing (fMUX) readout architecture. Our goal is to reduce the physical size of resonators, such that resonators and detectors can eventually be integrated on a single wafer. To reduce the size of these resonators, we have designed spiral inductors and interdigitated capacitors that resonate around 10–100 MHz, an order of magnitude higher frequency compared to current fMUX readout systems. The higher frequency leads to a wider bandwidth and would enable higher multiplexing factor than the current $$\sim $$ 50 detectors per readout channel. We will report on the simulation, fabrication method, characterization technique, and measurement of quality factor of these resonators.

The heterogeneous nature of orebodies introduces large uncertainties into all quantitative evaluations, process design and process predictions. Measuring the extent of the variability of ore competence will allow the design process to account for variation in process performance through a quantitative knowledge of its uncertainties related to ore hardness. The conventional JKMRC drop-weight test (JKDWT) establishes the relationship between input energy (Ecs) and product fineness (t10) from which the breakage potential parameter A × b can be estimated, by combining the broken progeny of groups of particles. A new method, the Extended Drop Weight Test (ExDWT), has been developed which is applied to individual particles and is therefore capable of capturing breakage heterogeneity at high resolution. This paper explores a number of features of the new method, based on breakage tests on individual particles from several different rock types. The results showed that more accurate descriptions of particle size resulted in higher (softer) A × b values which suggests that the standard method may have been over-estimating rock competence. Regular-shaped cores broken diametrally were found to have higher (softer) A × b values than axially broken cores and irregular shaped particles. These tests also suggested that the true ore intrinsic heterogeneity is the main source of breakage variability measured by the ExDWT. The mean A × b values determined by the ExDWT showed no statistical difference to those determined by the standard JKDWT method, but the standard deviation of the estimate was much lower. The results have demonstrated the potential of the new method for capturing the inherent heterogeneity of individual ore particles. Such information could be used to populate multi-component models of comminution.

This paper examines the hypothesis that the manual selection of rocks for inspection, testing or analysis is invariably biased towards the heavier (larger) particles in the population being sampled. If the property of interest, such as assay or breakage potential, is size-related then such a bias would lead to systematic errors in the estimation of this property. To test the hypothesis, human volunteers were asked to select a sample of 10 rocks from a tray of 100 rocks of known weights, with and without a blindfold, in duplicate. This was repeated for a number of different rock size ranges in the range −50 + 19 mm. A statistical analysis of the results confirms the hypothesis that in almost all cases the samples were of larger weight than that expected from the known weight of the population of rocks. The magnitude of the bias depended on conditions but was highest for the widest size range. It is also shown that the volunteers produced different results to each other. The blindfold reduced the bias in the narrow size ranges but increased it for the wide size range. These effects are likely to be less important for populations of narrow size range, but where a truly unbiased sample is required strategies are proposed using randomisation processes. Relying on unmoderated human selection will lead to samples which overestimate the weight of the population.

The significance of studying, monitoring and predicting blast induced vibration and noise level in mining and civil activities is justified in the capability of imposing damages, sense of uncertainty due to negative psychological impacts on involved personnel and also judicial complaints of local inhabitants in the nearby area. This paper presents achieved results during an investigation carried out at Sungun Copper Mine, Iran. Besides, the research also studied the significance of blast induced ground vibration and airblast on safety aspects of nearby structures, potential risks, frequency analysis, and human response. According to the United States Bureau of Mines (USBM) standard, the attenuation equations were developed using field records. A general frequency analysis and risk evaluation revealed that: 94% of generated frequencies are less than 14 Hz which is within the natural frequency of structures that increases risk of damage. At the end, studies of human response showed destructive effects of the phenomena by ranging between 2.54 and 25.40 mm/s for ground vibrations and by the average value of 110 dB for noise levels which could increase sense of uncertainty among involved employees. Keywords: Rock blasting, Peak particle velocity, Airblast, Frequency, Damage criteria, Risk evaluation

The environmental effects of blasting must be controlled in order to comply with regulatory limits. Because of safety concerns and risk of damage to infrastructures, equipment, and property, and also having a good fragmentation, flyrock control is crucial in blasting operations. If measures to decrease flyrock are taken, then the flyrock distance would be limited, and, in return, the risk of damage can be reduced or eliminated. This paper deals with modeling the level of risk associated with flyrock and, also, flyrock distance prediction based on the rock engineering systems (RES) methodology. In the proposed models, 13 effective parameters on flyrock due to blasting are considered as inputs, and the flyrock distance and associated level of risks as outputs. In selecting input data, the simplicity of measuring input data was taken into account as well. The data for 47 blasts, carried out at the Sungun copper mine, western Iran, were used to predict the level of risk and flyrock distance corresponding to each blast. The obtained results showed that, for the 47 blasts carried out at the Sungun copper mine, the level of estimated risks are mostly in accordance with the measured flyrock distances. Furthermore, a comparison was made between the results of the flyrock distance predictive RES-based model, the multivariate regression analysis model (MVRM), and, also, the dimensional analysis model. For the RES-based model, R 2 and root mean square error (RMSE) are equal to 0.86 and 10.01, respectively, whereas for the MVRM and dimensional analysis, R 2 and RMSE are equal to (0.84 and 12.20) and (0.76 and 13.75), respectively. These achievements confirm the better performance of the RES-based model over the other proposed models.

Most blasting operations are associated with various forms of energy loss, emerging as environmental side effects of rock blasting, such as flyrock, vibration, airblast, and backbreak. Backbreak is an adverse phenomenon in rock blasting operations, which imposes risk and increases operation expenses because of safety reduction due to the instability of walls, poor fragmentation, and uneven burden in subsequent blasts. In this paper, based on the basic concepts of a rock engineering systems (RES) approach, a new model for the prediction of backbreak and the risk associated with a blast is presented. The newly suggested model involves 16 effective parameters on backbreak due to blasting, while retaining simplicity as well. The data for 30 blasts, carried out at Sungun copper mine, western Iran, were used to predict backbreak and the level of risk corresponding to each blast by the RES-based model. The results obtained were compared with the backbreak measured for each blast, which showed that the level of risk achieved is in consistence with the backbreak measured. The maximum level of risk [vulnerability index (VI) = 60] was associated with blast No. 2, for which the corresponding average backbreak was the highest achieved (9.25 m). Also, for blasts with levels of risk under 40, the minimum average backbreaks (

The electrooxidation of Gabapentin was studied on nanotubes of nickel oxide-modified carbon paste electrode for the first time. Cyclic voltammetry was employed to investigate the electrooxidation process. A simple, sensitive, and efficient amperometric method was developed for the analysis of the drug, and the corresponding analytical parameters were reported. For Gabapentin, a detection limit of 0.3 μM was obtained in a linear range of 2.4–50 μM. The proposed amperometric method was also applied to the analysis of commercial capsules, and the results were in good agreement with the declared values. Also, the applicability of the method to the direct assay of the drug in human serum and urine was described.

The electrochemical behavior of sodium alendronate on copper microparticle- and copper nanoparticle-modified carbon paste electrodes was investigated. In the voltammograms recorded using microparticles, a single anodic oxidation peak appeared, while using nanoparticles, two anodic peaks appeared. The anodic currents were related to the electrocatalytic oxidation of alendronate via the active species of Cu(III). The catalytic rate constant for the electrocatalytic oxidation process and the diffusion coefficient of alendronate were obtained to be 1.57 × 103 cm3 mol−1 s−1 and 2.44 × 10−6 cm2 s−1, respectively. A sensitive and time-saving detection procedure was developed for the analysis of alendronate, and the corresponding analytical parameters were reported. Alendronate was determined with a limit of detection of 11.26 μmol L−1 with a linear range of 50–6,330 μmol L−1. The proposed amperometric method was applied to the analysis of commercial pharmaceutical tablets, and the results were in good agreement with the declared values.

O comportamento eletroquimico e a determinacao de um bisfosfonato, o etidronato de sodio, em tres diferentes eletrodos de cobre: eletrodo de cobre policristalino (CE) e eletrodos de pasta de carbono modificados com microparticulas de cobre (m-CPE) e nanoparticulas de cobre (n-CPE) foi investigado. Usando o eletrodo CE, os voltamogramas apresentaram um pico de corrente anodica, enquanto com m-CPE e n-CPE, foram observados dois picos de corrente de oxidacao. A densidade de corrente anodica em 610 mV para n-CPE e cinco vezes maior do que para m-CPE. Isto esta relacionado ao efeito do tamanho das nanoparticulas de cobre. As correntes anodicas foram relacionadas a oxidacao eletrocatalitica do etidronato via eletrogeracao de especies ativas de Cu(III) em um mecanismo EC'. Os valores para a constante de velocidade catalitica para o processo de oxidacao e o coeficiente de difusao do etidronato foram 8,9 × 103 cm3 mol-1 s-1 e 1,55 × 10-6 cm2 s-1, respectivamente. Um procedimento sensivel e rapido foi desenvolvido para a analise de etidronato, e os parâmetros analiticos correspondentes foram relatados. O etidronato foi determinado com um intervalo linear de 10,57 μmol L-1 e um limite de deteccao de 200-2538 μmol L-1. A exatitude foi checada pela aplicacao do teste de recuperacao nas amostras. O metodo amperometrico proposto foi aplicado a analise de comprimidos farmaceuticos comerciais e os resultados apresentaram concordância com os valores de literatura.

The purpose of blasting in open-pit mines is achieving a desired fragment size distribution, considering safety and environmental aspects. Regarding economic aspects, fragmentation plays a critical role in the total costs of mining operation. Poor fragmentation, oversize and undersize, means economic loss and as a consequence, putting the whole mining operation at risk. Risk assessment prior to blasting operation can be a helpful tool for total cost reduction. This paper presents a new model to analyze the risk due to poor fragmentation in rock blasting, based on the concept of Rock Engineering Systems (RES). The principles of RES were used to define an index, the so called vulnerability index (VI), expressing the risk condition due to poor fragmentation. In defining the new model, two main steps must be taken into account. The first step is to identify the parameters that are responsible for the occurrence of risk in the case of fragmentation (poor fragmentation), analyze their behavior and evaluate the significance (weight) that each one has in the overall risk conditions (poor fragmentation). In this step, the RES principles can be used to assess the weighting of the parameters involved. In the second step, the vulnerability index can be determined, which shows the level of risk expected for each blast. The data for 30 blasts, carried out in Sungun copper mine, western Iran, were used to validate the model. The results obtained indicating the capability of the model proposed.

CSM patients caused by osteophytic ridge or intervertebral disc herniation underwent anterior decompression and fusion were prospectively enrolled. The purpose was to elucidate the effects of decompression (anterior cervical discectomy and fusion) on myelopathic cord in milder cases, younger patients, and in short duration of the disease.Forty-three patients with CSM were examined comprising Cooper and mJOA scale before and after surgery and followed for 12 months.Patients included in the study were 30 males and 13 females. The mean age of men was 50.9±13.2, and that of women was 46.8±11.8. The mean interval from symptoms onset to hospital presentation was 10.78±7.3 months. In lower limbs, among 31 with preoperative functional impairment, 25 remained unchanged, three improved and three worsened, which is not significant, and of 39 patients with preoperative upper limb functional impairments using Cooper's scale, 20 improved, 15 remained unchanged and 4 became worse (P=0.001). Recovery rate for mJOA score was 24.5±17.7%, for Cooper lower extremity score was 32.2±40.56% and for Cooper upper extremity score was 7.8±16.8%. The mean gain in mJOA was 0.84 (±0.57).Patients with short duration of symptom onset respond remarkably to decompression surgery. In patients with good condition that myelopathy has not established yet, perhaps mJOA is not a perfect and powerful scale for pre and postoperative assessment of patient.

Simultaneous intradural, extradural, vertebral and paravetebral invasion of hydatid cyst, pathologic fracture, and multiple vertebral involvement are all rare encountered conditions in echinococcal infestation. A 48-year-old man who had experienced a falling down trauma, 10 years ago, and at that time, because of L1 burst fracture, undergone on Harrington rod placement, admitted in our ward for newly started urinary retention and mild paresis of lower extremities. With imaging analysis and during surgery, we discovered the extension of echinococcal spinal infestation extra- and intradurally after a decade of extinction. We performed a double stage circumferential reconstruction and adjuvant long term chemotherapy. We closely monitor our patient neurologically and radiologically and believe that aggressive surgical treatment and sustained cyclical albendazole therapy can increase the quality of life and life expectancy.

The electrocatalytic oxidation of metformin was studied on a nickel oxide nanotubes-carbon microparticles/Nafion nanocomposite, using cyclic voltammetry and chronoamperometry. In the presence of metformin, the anodic peak current of the Ni(II)/Ni(III) transition increased, followed by a decrease in the corresponding cathodic currents. Based on the results, the drug was oxidized on nickel oxide nanotubes via an electrocatalytic mechanism. The catalytic rate constant, the electron transfer coefficient and the diffusion coefficient involved in the electrocatalytic oxidation of the drug were reported. A sensitive and efficient amperometric method was presented for the analysis of the drug, and the corresponding analytical parameters were reported. For metformin, a detection limit of 0.45 μmol L −1 was obtained. The proposed amperometric method was also applied to the analysis of commercial tablets and the results were in good agreement with the declared values. Also, the applicability of the method to the direct assays of the drug in human serum and urine and breast milk was described.