Single Trace Research Articles

Проектирование технологии обработки в гранулированных средах в условиях цифрового производства

The problem of mechanical technology design for machining parts in granulated media in the conditions of digital produc-tion is viewed. The peculiarities of part process in abrasive media and with steel balls (finish- machining and strengthening treatment techniques) are shown. Dependences for determining the parameters of a single interaction of a medium particle with the surface of a part during processing in granulated media are obtained. Dependences for depth maximizing in cases of particle penetration into the surface of the machined part, the parameters of a single trace, surface roughness, processing time are found. For finish- machining and strengthening treatment techniques for granulated working media, dependences for determining the depth of the hardened layer and the degree of deformation are also obtained. The obtained theoretical dependences have been tested for adequacy through drawing an analogy with the results of experimental studies. During the research, it was found that the developed system of models does not take into account the peculiarities of various processing methods and their dynamics, and shape of the particles of the medium. To account all these parameters, the Rocky DEM ap-plication software package is used. The package allows modeling the processing chamber, the dynamic parameters of the machining process, the number of particles in the working space according to their mass, the shape and dimensions of the particles, the mass and shape of the machined part and its location in the processing chamber, the material of the machined part, the ratio of the mass of the part and the mass of the abrasive medium, some physical properties of the material of the processed part, slip coefficient of the abrasive medium on the part surface, process liquid properties and other parameters. The package made it possible to refine theoretical models and obtain results closer to production conditions. Based on the research carried out and being aimed at their introduction into modern digital production, the design technique of techno-logical processes has been developed and a software product has been proposed allowing to select possible working meth-ods in granulated media (in order of preference) according to the characteristics of the part, and to determine the technolog-ical modes for each of them and characteristics of working environments.

Performance of Single-Lead Handheld Electrocardiograms for Atrial Fibrillation Screening in Primary Care: The VITAL-AF Trial

BackgroundHandheld single-lead electrocardiographic (1L ECG) devices are increasingly used for atrial fibrillation (AF) screening, but their real-world performance is not well understood. ObjectivesThe purpose of this study was to quantify the diagnostic test characteristics of 1L ECG automated interpretations for prospective AF screening. MethodsWe calculated the diagnostic test characteristics of the AliveCor KardiaMobile 1L ECG (AliveCor, US) algorithm using unblinded cardiologist overread as the gold standard using single 30s tracings administered by medical assistants among individuals aged ≥65 years participating in the VITAL-AF trial (NCT03515057) of population-based AF screening embedded within routine primary care. ResultsA total of 14,230 individuals (mean age 74 ± 7 years, 60% women, 82% White) had 31,376 tracings reviewed by 13 cardiologists. A total of 24,906 (79.6%) tracings had an AliveCor interpretation of normal, 5,046 (16.1%) were unclassified, 797 (2.5%) were possible AF, and 573 (1.8%) were no analysis. Cardiologists read 808 (2.6%) tracings as AF. AliveCor possible AF had a PPV of 51.7% (95% CI: 47.8%-55.6%). AliveCor normal had an NPV of 99.8% (95% CI: 99.7%-99.8%). The AliveCor algorithm had an overall sensitivity of 51.0% (95% CI: 47.1%-54.9%) and a specificity of 98.7% (95% CI: 98.6%-98.9%). AliveCor tracings interpreted as unclassified (PPV 5.9%, 95% CI: 5.1%-6.7%) and no analysis (PPV 6.5%, 95% CI: 4.6%-8.9%) had low predictive values for AF and were increasingly prevalent at older ages (13.7% for age 65-69 years to 28.1% for age ≥85 years, P < 0.01). ConclusionsIn an older primary care population undergoing AF screening with handheld 1L ECGs, automated algorithm interpretations were sufficiently accurate to exclude the presence of AF but not to establish an AF diagnosis.

Wilson-loop one-point functions in ABJM theory

In this paper we initiate the study of correlation functions of a single trace operator and a circular supersymmetric Wilson loop in ABJM theory. The single trace operator is in the scalar sector and is an eigenstate of the planar two-loop dilatation operator. The Wilson loop is in the fundamental representation of the gauge group or a suitable (super-)group. Such correlation functions at tree level can be written as an overlap of the Bethe state corresponding to the single trace operator and a boundary state which corresponds to the Wilson loop. There are various type of supersymmetric Wilson loops in ABJM theory. We show that some of them correspond to tree-level integrable boundary states while some are not. For the tree-level integrable ones, we prove their integrability and obtain analytic formula for the overlaps. For the non-integrable ones, we give examples of non-vanishing overlaps for Bethe states which violate selection rules.

Low Trace-Count Template Attacks on 32-bit Implementations of ASCON AEAD

The recently adopted Ascon standard by NIST offers a lightweight authenticated encryption algorithm for use in resource-constrained cryptographic devices. To help assess side-channel attack risks of Ascon implementations, we present the first template attack based on analyzing power traces, recorded from an STM32F303 microcontroller board running Weatherley’s 32-bit implementations of Ascon-128. Our analysis combines a fragment template attack with belief-propagation and key-enumeration techniques. The main results are three-fold: (1) we reached 100% success rate from a single trace if the C compiler optimized the unmasked implementation for space, (2) the success rate was about 95% after three traces if the compiler optimized instead for time, and (3) we also attacked a masked version, where the success rate was over 90% with 20 traces of executions with the same key, all after enumerating up to 224 key candidates. These results show that suitably-designed template attacks can pose a real threat to Ascon implementations, even if protected by first-order masking, but we also learnt how some differences in programming style, and even compiler optimization settings, can significantly affect the result.

Information loss, mixing and emergent type III1 factors

A manifestation of the black hole information loss problem is that the two-point function of probe operators in a large Anti-de Sitter black hole decays in time, whereas, on the boundary CFT, it is expected to be an almost periodic function of time. We point out that the decay of the two-point function (clustering in time) holds important clues to the nature of observable algebras, states, and dynamics in quantum gravity.We call operators that cluster in time “mixing” and explore the necessary and sufficient conditions for mixing. The information loss problem is a special case of the statement that in type I algebras, there exists no mixing operators. We prove that, in a thermofield double state (KMS state), if mixing operators form an algebra (close under multiplication), the resulting algebra must be a von Neumann type III1 factor. In other words, the physically intuitive requirement that all nonconserved operators should exponentially mix is so strong that it fixes the observable algebra to be an exotic algebra called a type III1 factor. More generally, for an arbitrary out-of-equilibrium state of a general quantum system (von Neumann algebra), we show that if the set of operators that mix under modular flow forms an algebra, it is a type III1 von Neumann factor.In a theory of Generalized Free Fields (GFF), we show that if the two-point function clusters in time, all operators are mixing, and the algebra is a type III1 factor. For example, in \U0001d4a9 = 4 SYM, above the Hawking-Page phase transition, clustering of the single trace operators implies that the algebra is a type III1 factor, settling a recent conjecture of Leutheusser and Liu. We explicitly construct the C∗-algebra and von Neumann subalgebras of GFF associated with time bands and, more generally, open sets of the bulk spacetime using the HKLL reconstruction map.

Separating Oil and Vinegar with a Single Trace

Due to recent cryptanalytical breakthroughs, the multivariate signature schemes that seemed to be most promising in the past years are no longer in the focus of the research community. Hence, the cryptographically mature UOV scheme is of great interest again. Since it has not been part of the NIST process for standardizing post-quantum cryptography so far, it has not been studied intensively for its physical security.In this work, we present a side-channel attack on the latest implementation of UOV. In the first part of the attack, a single side-channel trace of the signing process is used to learn all vinegar variables used in the computation. Then, we employ a combination of the Kipnis-Shamir attack and the reconciliation attack to reveal the complete secret key. Our attack, unlike previous work, targets the inversion of the central map and not the subsequent linear transformation. It further does not require the attacker to control the message to be signed.We have verified the practicality of our attack on a ChipWhisperer-Lite board with a 32-bit STM32F3 ARM Cortex-M4 target mounted on a CW308 UFO board. We publicly provide the code and both reference and target traces. Additionally, we discuss several countermeasures that can at least make our attack less efficient.

A large twist limit for any operator

We argue that for any single-trace operator in mathcal{N} = 4 SYM theory there is a large twist double-scaling limit in which the Feynman graphs have an iterative structure. Such structure can be recast using a graph-building operator. Generically, this operator mixes between single trace operators with different scaling limits. The mixing captures both the finite coupling spectrum and corrections away from the large twist limit. We first consider a class of short operators with gluons and fermions for which such mixing problems do not arise, and derive their finite coupling spectra. We then focus on a class of long operators with gluons that do mix. We invert their graph-building operator and prove its integrability. The picture that emerges from this work opens the door to a systematic expansion of mathcal{N} = 4 SYM theory around the large twist limit.

Automatic single fish detection with a commercial echosounder using YOLO v5 and its application for echosounder calibration

Nowadays, most fishing vessels are equipped with high-resolution commercial echo sounders. However, many instruments cannot be calibrated and missing data occur frequently. These problems impede the collection of acoustic data by commercial fishing vessels, which are necessary for species classification and stock assessment. In this study, an automatic detection and classification model for echo traces of the Pacific saury (Cololabis saira) was trained based on the algorithm YOLO v5m. The in situ measurement value of the Pacific saury was measured using single fish echo trace. Rapid calibration of the commercial echo sounder was achieved based on the living fish calibration method. According to the results, the maximum precision, recall, and average precision values of the trained model were 0.79, 0.68, and 0.71, respectively. The maximum F1 score of the model was 0.66 at a confidence level of 0.454. The living fish calibration offset values obtained at two sites in the field were 116.30 dB and 118.19 dB. The sphere calibration offset value obtained in the laboratory using the standard sphere method was 117.65 dB. The differences between in situ and laboratory calibrations were 1.35 dB and 0.54 dB, both of which were within the normal range.

Generalized chemical model for plasmas with application to the ionization potential depression

On the basis of the generalized Poisson–Boltzmann equation derived from the Bogolyubov chain of equations for the equilibrium distribution functions in the pair correlation approximation, a general expression is proposed for the Helmholtz free energy of a system that contains any number of components and whose particles interact via arbitrary potentials. This opens up an extraordinary opportunity to simultaneously treat a whole range of physical effects including partial ionization, quantum effects of diffraction and electron degeneracy, short- and long-range interactions of charged particles with neutrals, finite size effects, etc. It is shown that all medium constituents are tied together in a single screening matrix, whose determinant and trace determine the excess contribution to the free energy. The approach developed is then applied to the problem of the ionization potential depression (IPD) leading to quite simple analytical expressions, which turn out to be useful for various practical purposes. In particular, for a single ionization from the neutral state the IPD is shown to significantly depend on the ionization degree such that it consists of the difference of charged and neutral contributions for a fully ionized plasma and turns non-zero for an almost neutral medium. On the other hand, for a multiple ionization process finite size effects of atoms and ions are demonstrated to be of great importance and accounted for in order to achieve good agreement with experimental data on the IPD under warm dense matter conditions.

Orbit averaging coherent states: holographic three-point functions of AdS giant gravitons

We study correlation functions of two AdS giant gravitons in AdS5 × S5 and a BPS supergravity mode using holography. In the gauge theory these are described by BPS correlators of Schur polynomials of fully-symmetric representations and a single trace operator. We find full agreement between the semiclassical gravity and gauge theory computations at large N, for both diagonal and off-diagonal structure constants. Our analysis in mathcal{N} = 4 SYM provides a simpler derivation to the results in the literature, and it can be readily generalized to operators describing bound states of AdS giant gravitons as well as bubbling geometries.

Association between prenatal exposure to trace elements mixture and visual acuity in infants: A prospective birth cohort study

BackgroundPrenatal environmental factors may affect the development of the offspring and can bring long lasting consequences to the offspring's health. To date, only few studies have reported inconclusive association between prenatal single trace element exposure and visual acuity, and no studies have investigated the association between prenatal exposure to trace elements mixture and visual acuity in infants. MethodsIn the prospective cohort study, grating acuity in infants (12 ± 1 months) was measured by Teller Acuity Cards II. Concentrations of 20 trace elements in maternal urine samples collected in early-trimester were measured by Inductively Coupled Plasma Mass Spectrometry. Elastic net regression (ENET) was applied to select important trace elements. Nonlinear associations of the trace elements levels with abnormal grating were explored using the restricted cubic spline (RCS) method. The associations between selected individual elements and abnormal grating acuity were further appraised using the logistic regression model. Then Bayesian Kernel Machine Regression (BKMR) was used to estimate the joint effects of mixture and interactions between trace elements combining with NLinteraction. ResultsOf 932 mother-infant pairs, 70 infants had abnormal grating acuity. The ENET model produced 8 trace elements with non-zero coefficients, including cadmium, manganese, molybdenum, nickel, rubidium, antimony, tin and titanium. RCS analyses identified no nonlinear associations of the 8 elements with abnormal grating acuity. The single-exposure analyses using logistic regression revealed that prenatal molybdenum exposure possessed a significantly positive association with abnormal grating acuity (odds ratio [OR]: 1.44 per IQR increase, 95% confidence interval [CI]: 1.05, 1.96; P = 0.023), while prenatal nickel exposure presented with a significantly inverse association with abnormal grating acuity (OR: 0.64 per IQR increase, 95% CI: 0.45, 0.89; P = 0.009). Similar effects were also observed in BKMR models. Moreover, the BKMR models and NLinteraction method identified potential interaction between molybdenum and nickel. ConclusionsWe established that prenatal exposure to high concentration of molybdenum and low concentration of nickel was associated with the increased risk of abnormal visual acuity. Potential interaction may exist between molybdenum and nickel on abnormal visual acuity.

Geophysical Characterization and Attenuation Correction Applied for Hydrate Bearing Sediments in Japan Sea

Estimation of rock properties from seismic data is important for exploration and production activities in the petroleum industry. Considering the compressional velocity—the speed of propagating body waves in formations—and the quality factor (Q)—a measure of the frequency-selective energy losses of waves propagating through formations—both properties are usually estimated from multichannel seismic data. Velocity is estimated during multichannel processing of seismic reflection data in either the time or depth domain. In marine seismic acquisition, Q can be estimated from the following sources: Vertical Seismic Profile (VSP) surveys, where sources are located near the sea surface and geophones are distributed at depth along a borehole; and multichannel reflection data, where sources are also located near the sea surface and receivers are distributed either at the sea surface (conventional seismic survey with streamers) or on the sea floor (use of nodes or Ocean Bottom Cables (OBC)). The aforementioned acquisition devices, VSP, conventional streamers, nodes, and OBCs are much more expensive than single-channel acquisition with one receiver per shot due to the cost of operation. There are numerous old and new datasets from academia and the oil industry that have been acquired with single-channel acquisition devices. However, there is a paucity of work addressing the estimation of velocity and Q from this type of equipment. We investigate the estimation of Q and velocity from single-channel seismic data. Using the windowed discrete Fourier transform for a single seismic trace, we calculate the peak and dominant frequency that changes with time. In the geologic environment, higher frequencies are attenuated at shallow depths (time), while lower frequencies remain at deeper positions. From the rate at which higher frequencies are attenuated with time, we estimate the effective quality factor (Qeff). However, when using Kirchhoff migration to process single-channel seismic data, events far from the vertical projection of the receiver contribute to the trace at a given time. Then, an underestimation of the effective quality factor occurs. To compensate for the effects of more distant events with lower-frequency content contaminating the shorter events, we propose a linear equation to correct the effective quality factor estimated from migrated seismic data. Effective Q and its correction are estimated in five single-channel seismic lines surveyed along the Joetsu Knoll, a SW-NE anticline structure on the eastern margin of the Sea of Japan. These results are linked to geomorphological and geological features and the velocity field. Joetsu Knoll is a known site of massive gas hydrates (GH), which occur in the first hundred metres of Neogene sediments and, together with gas chimneys, play an important role in seismic wave absorption. Qeff estimated from migrated seismic data maintains the spatial relationship between high and low Q regions. The region of low Q, which is below 124 and has an average value of 57, occurs near the anticlinal hinge and tends to coincide with the region in which the Bottom Simulating Reflector (BSR) resides. The coexistence of GH and free gas coincides with the very low P velocity gradient of 0.225 s−1. BSR occurrence, Qeff and the geometry of the Joetsu anticline testify to progressive gas hydrate depletion northward along the dome.

Seismic Facies Recognition of Ultra-Deep Carbonate Rocks Based on Convolutional Neural Network

Seismic facies is a seismic reflection unit defined by specific seismic reflection characteristics, that is, the seismic responses of sedimentary facies or geological bodies, whose accuracy will directly affect the reliability of oil and gas exploration results. Currently, seismic facies is generally recognized depending upon the differences between certain single trace seismic attributes (waveform, frequency spectrum, and amplitude, etc.) and adjacent units to conduct cluster analysis. Such methods, however, have ambiguity in identifying special reflective structures with continuous waveforms (e.g. massive carbonate deposits). In order to solve this problem, this paper incorporates artificial intelligence (AI) technology into automatic recognition of seismic facies with special reflection structures. Firstly, a 2D seismic facies classification sample label set is designed and formed. Then, a seismic facies prediction model is designed and constructed using a multi-layer convolutional neural network (CNN). Finally, the trained model is used to automatically track the seismic facies in the study area. This method was applied to seismic facies recognition for the Sinian Dengying Formation in an area of the Sichuan Basin, and the seismic facies recognized were compared with artificially interpreted ones. It is confirmed that the proposed method provides a better effect than artificial interpretation, with greatly improved accuracy and efficiency.

Abstract 720: Integration Of Population Genetic And Human Knockout Studies With Smooth Muscle Cell Lineage Tracing In Mouse Models Identifies Novel Targets For Atherosclerosis And Cardiovascular Risk.

Despite lipid-lowering therapies, residual cardiovascular disease risk remains a major unmet clinical need. Large-scale genetic analyses have identified &gt;250 loci for coronary artery disease (CAD) risk. Genes that function in vascular smooth muscle cells (SMC) are causal at several loci, yet the causal genes at most loci remain unknown. Using single cell profiling and SMC lineage tracing in mouse models, we and others have shown that SMC transition through an intermediate state to SMC-derived cells (SDC) with protective or harmful phenotypes for plaque stability. In this study, we integrated SMC lineage tracing in mouse models with ongoing analyses in &gt; 1 million human participants with whole-genome (WGS) and whole-exome sequencing (WES) data, as well as rare variant analysis of human “knockouts” (homozygous for predicted loss-of-function variants) for a novel gene discovery pipeline (Figure 1). Through WES in 76,000 highly consanguineous participants in the Pakistan Genomic Resource (PGR), we assembled the largest global cohort of human KOs. At non-lipid CAD loci from a recent large multi-ethnic meta-analysis (~1.1 million participants), we prioritized genes as potentially causal in SMC/SDC as those that are expressed and regulated in human or mouse arteries and SMC in atherosclerosis progression. Through gene burden testing and analyses of rare predicted loss-of-function (pLoF) and damaging (pDMs) variants in the largest CAD WES/WGS meta-analyses we enriched for causal genes. We restricted to genes with at least 5 pLoF carriers in PGR to facilitate recall studies in Pakistan. Final prioritization incorporated state-of-the-art fine mapping and co-localization analyses as well as biological plausibility. From an initial pool of 1696 genes, our gene discovery pipeline prioritized 15 SMC/SDC genes, and initial recall in PGR identified multiple large pedigrees for mutations in candidate causal genes PDE3A, SERPINH1, HHIPL1, and ZEB2.

DRAG in situ barcoding reveals an increased number of HSPCs contributing to myelopoiesis with age

Ageing is associated with changes in the cellular composition of the immune system. During ageing, hematopoietic stem and progenitor cells (HSPCs) that produce immune cells are thought to decline in their regenerative capacity. However, HSPC function has been mostly assessed using transplantation assays, and it remains unclear how HSPCs age in the native bone marrow niche. To address this issue, we present an in situ single cell lineage tracing technology to quantify the clonal composition and cell production of single cells in their native niche. Our results demonstrate that a pool of HSPCs with unequal output maintains myelopoiesis through overlapping waves of cell production throughout adult life. During ageing, the increased frequency of myeloid cells is explained by greater numbers of HSPCs contributing to myelopoiesis rather than the increased myeloid output of individual HSPCs. Strikingly, the myeloid output of HSPCs remains constant over time despite accumulating significant transcriptomic changes throughout adulthood. Together, these results show that, unlike emergency myelopoiesis post-transplantation, aged HSPCs in their native microenvironment do not functionally decline in their regenerative capacity.

A Single-Input Single-Output Sensing Scheme for Multiple Traces via Internal Resonance in Coupled Oscillators

Trace detection of multiple substances is crucial for public health and safety, chemical production, scientific research, and so on. A single trace is detectable via various methods, while the quantitative detection of multiple traces is still facing challenges. In this work, a single-input single-output (SISO) sensing scheme for multiple traces via internal resonance in coupled oscillators is proposed. An E-shaped coupled resonator is designed as an example for identifying and detecting three traces. Theoretical results, which have been verified by numerous simulations, indicate that high sensitivities, high linearity, low errors, and SISO detection can be realized. Moreover, the proposed scheme is not limited by the mass ratio of the three traces, and it can be widely applied for various practical scenarios. The generality of the proposed scheme for multiple traces is also preliminarily demonstrated with a 5-DOF internal resonance system (IRS). It is believable that the proposed scheme is applicable to any number of traces. This work not only widens the theoretical content of internal resonance but also opens a new avenue for the quantitative detection of multiple traces.

Health risk assessment of trace elements in the Tonle Sap Great Lake and the Tonle Sap River in Cambodia during the rainy season.

To investigate the potential health risk of trace elements in the Tonle Sap Great Lake system, lake (n = 37) and river (n = 14) water samples were collected and analyzed for 19 trace elements (Ag, Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Ga, Mn, Mo, Ni, Pb, Se, Tl, U and Zn) using inductively coupled plasma mass spectrometry. As a result, Cd was not detected in any river and lake water samples. Al, Fe and Mn in lake water exceeded the regulation limits of Cambodia, USEPA and WHO. Health risk assessment using the USEPA model indicated that male and female Cambodian residents are at minimal risk of non-carcinogenic effects from single and mixed trace elements through lake and river water consumption. Nevertheless, As, Tl, Co, Ba, Mn and Cr might pose high potential health risks to consumers which requires more attention. Therefore, regular monitoring and further studies are required to investigate the pollution trends and toxic behavior of these trace elements in the Tonle Sap Great Lake system.

Mean age from observations in the lowermost stratosphere: an improved method and interhemispheric differences

Abstract. The age of stratospheric air is a concept commonly used to evaluate transport timescales in atmospheric models. The mean age can be derived from observations of a single long-lived trace gas species with a known tropospheric trend. Commonly, deriving mean age is based on the assumption that all air enters the stratosphere through the tropical (TR) tropopause. However, in the lowermost stratosphere (LMS) close to the extra-tropical (exTR) tropopause, cross-tropopause transport needs to be taken into account. We introduce the new exTR–TR method, which considers exTR input into the stratosphere in addition to TR input. We apply the exTR–TR method to in situ SF6 measurements from three aircraft campaigns (PGS, WISE and SouthTRAC) and compare results to those from the conventional TR-only method. Using the TR-only method, negative mean age values are derived in the LMS close to the tropopause during the WISE campaign in Northern Hemispheric (NH) fall 2017. Using the new exTR–TR method instead, the number and extent of negative mean age values is reduced. With our new exTR–TR method, we are thus able to derive more realistic values of typical transport times in the LMS from in situ SF6 measurements. Absolute differences between both methods range from 0.3 to 0.4 years among the three campaigns. Interhemispheric differences in mean age are found when comparing seasonally overlapping campaign phases from the PGS and the SouthTRAC campaigns. On average, within the lowest 65 K potential temperature above the tropopause, the NH LMS is 0.5±0.3 years older around March 2016 than the Southern Hemispheric (SH) LMS around September 2019. The derived differences between results from the exTR–TR method and the TR-only method, as well as interhemispheric differences, are higher than the sensitivities of the exTR–TR method to parameter uncertainties, which are estimated to be below 0.22 years for all three campaigns.

Distribution, Risk Assessment and Source Identification of Potentially Toxic Elements in Coal Mining Contaminated Soils of Makarwal, Pakistan: Environmental and Human Health Outcomes

The present research was carried out to examine the health and environmental impacts associated with coal mining activities in the Makarwal coal mining area in Pakistan. To achieve the objectives, 41 soil samples were collected from the coalmine-affected areas and analyzed for major and toxic trace elements (TTEs) using atomic absorption spectroscopy. Most of the soil samples have extremely high concentrations of toxic metals such as Ni, Cd, Cr, Cu, Zn, and Pb. The positive correlations and high concentration of trace elements in the Makarwal coalmine-affected region suggest an analogous origin of soil contamination. The factor analysis (FA) showed two components, i.e., F1 (53.4%) and F (74.21%), of total variability for soil. The F2 was loaded with Pb, Zn, Ni, and Cr, which was similar to cluster 2, while the F1 was loaded with Cu and Cr, having a similar pattern to cluster 1. This proves that the contamination in the surrounding area is mostly associated with geological ore strata existing in the Makarwal coalfield. Based on geoaccumulation (Igeo), the elemental concentration in the studied soil sample could be categorized as follows: (1) Pb, Ni, and Zn are moderate to severely polluted and (2) Cr and Cu are in the moderately polluted category. The ecological risk indices (ERIs) of the single trace element contamination index highlighted that Cd, Pb, Ni, and Cr pose a high risk to humans and the ecosystem. Based on different statistical tools performed for the source identification and distribution of metal contamination, it seems that the exposed sedimentary rocks, including limestone, dolomite, sandstone, and coal, are responsible for the toxic metal contamination in the study area.

Integrated Identification of Lithology Using Seismic and Magnetic Anomaly Data for Granite and Gneiss Basement: A Case Study of the LiShui Depression in the East China Sea Basin

Granite and gneiss buried hill reservoirs are controlled by their lithology and dark mineral content. Therefore, lithological identification and dark mineral content analysis are important research tools in the early stage of buried hill exploration. In this paper, the relationships between the seismic facies and lithology, magnetic susceptibility, and magnetic anomalies of granite and gneiss are analyzed based on the lithological characteristics of the LiShui depression (LS depression) in the East China Sea Basin (ECSB). The waveform classification method is used to identify granite and gneiss, and the waveform classification results reveal that areas with continuous distribution of a single seismic trace model or two seismic trace models represent good continuity, and can be interpreted as gneiss. Areas with a mixed distribution of multiple seismic trace models represent chaotic and poor continuity, which can be interpreted as granite. The mixed linear zone with multi-seismic trace models is a fault zone, and the rock is cataclasite. In addition, reduction to the pole (RTP) and downward continuation technique for magnetic data processing were used to determine the dark mineral content. Overall, the granite and gneiss can be divided into three types based on magnetic anomaly data: high, moderate, and low magnetic anomaly areas. The areas in which granite with moderate and low magnetic anomalies is distributed are the favorable exploration target areas. The above method provides a technical means of lithological identification in the early stage of buried hill exploration.