Maximum Imbalance Research Articles

DEPArray™ single-cell technology: A validation study for forensic applications

In forensics investigations, it is common to encounter biological mixtures consisting of homogeneous or heterogeneous components from multiple individuals and with different genetic contributions. One promising mixture deconvolution strategy is the DEPArray™ technology, which enables the separation of cell populations before genetic analysis. While technological advances are fundamental, their reliable validation is crucial for successful implementation and use for casework. Thus, this study aimed to 1) systematically validate the DEPArray™ system concerning specificity, sensitivity, repeatability, and contamination occurrences for blood, epithelial, and sperm cells, and 2) evaluate its potential for single-cell analysis in the field of forensic science. Our findings confirmed the effective identification of different cell types and the correct assignment of successfully genotyped single cells to their respective donor(s). Using the NGM Detect™ Amplification Kit, the average profile completeness for diploid cells was approximately 80%, with ∼ 290 RFUs. In contrast, haploid sperm analysis yielded an average completeness of 51% referring to the haploid reference profile, accompanied by mean peak heights of ∼ 176 RFUs. Although certain alleles of heterozygous loci in diploid cells showed strong imbalances, the overall peak balances yielded acceptable values above ≥ 60% with a mean value of 72% ± 0.21, a median of 77%, but with a maximum imbalance of 9% between heterozygous peaks. Locus dropouts were considered stochastic events, exhibiting variations among donors and cell types, with a notable failure incidence observed for TH01. Within the wet-lab experimentation with >500 single cells for the validation, profiling was performed using the consensus approach, where profiles were selected randomly from all data to better mirror real casework results. Nevertheless, complete profiles could be achieved with as few as three diploid cells, while the average success rate increased to 100% when using profiles of 6–10 cells. For sperms, however, a consensus profile with completeness >90% of the autosomal diploid genotype could be attained using ≥15 cells. In addition, the robustness of the consensus approach was evaluated in the absence of the respective reference profile without severe deterioration. Here, increased stutter peaks (≥ 15%) were found as the main artifact in single-cell profiles, while contamination and drop-ins were ascertained as rare events. Lastly, the technique’s potential and limitations are discussed, and practical guidance is provided, particularly valuable for cold cases, multiple perpetrator rapes, and analyses of homogeneous mixed evidence.

Measuring competitive balance in sports leagues that award bonus points, with an application to rugby union

We examine within-season competitive balance measurement in sports leagues where points allocated in each match depend on bonus points awarded as well as the win/draw/loss outcome, as in rugby union. The bilateral nature of matches imposes constraints on the range of competitive balance measures, as teams cannot win matches in which they do not play. Application of normalized competitive balance indices requires knowing the maximum value the index can attain, representing the most unequal distribution of points among teams. However, evaluation of the points distribution consistent with maximum imbalance is non-trivial when the total points allocated are not known in advance, as when bonus points are awarded. We theoretically derive the corresponding perfectly unbalanced distribution of points, characterized as a ‘Double Cascade distribution’, and provide an Excel tool to obtain it for different parameter values. We apply our results to examine variation in within-season competitive balance in the Six Nations Championship in rugby. The degree of competitive balance, as measured by a normalized concentration index, has improved since the award of bonus points in 2017, primarily because the index's maximum value increases with bonus points. However, with limited available data on the bonus-points regime, it is not possible to establish or reject a causal link, due to induced behavioural changes by teams, between the raw concentration index and bonus points. A relatively high level of imbalance still exists compared to other sports leagues, which will be an important consideration in evaluating future developments of the competition.

Комплексная оценка пространственного развития Ростовской области

At present, such a scientific category as the spatial development of territories is still insufficiently studied and in need of further conceptualization. And although the main directions of the country’s and region’s spatial development are presented in scientific discourse and government documents, their implementation in the region requires their specification, taking into account regional natural resource conditions, the characteristics of the socio-economic and environmental development of territorial entities. The present study attempts to fill this gap. It is devoted to presenting the results of the development of an original methodology for assessing the level of spatial development at the regional level. The Rostov region was chosen as the object under study, on the example of which the essence of the developed methodology is revealed. The presented methodology includes spatial differentiation of the territory, establishing the territorial structure of the region, determining the level of socio-economic and environmental development of territorial entities, assessing their balance, identifying problems and prospects for spatial development. In addition, this paper highlights the main factors of the spatial development of the region, which include economic, demographic, natural resource potentials, the state of the environment, the level and quality of life of the population. In the work, on the basis of calculated and detailed integral indicators for each municipality of the Rostov region, the territorial features of socio-economic and environmental development and the main problems of the spatial development of the Rostov region are established, the territories that are characterized by the maximum imbalance of development are identified.

NEPHROPROTECTIVE THERAPY IN ACUTE PERITONITIS

Increasing the effectiveness of peritonitis treatment remains an urgent issue for abdominal urgent surgery. So far, several effective surgical technologies have been developed. However, conservative therapy in the early postoperative period is an object for development, including the target organ protection influence.
 The aim of the study is to determine the nephroprotective efficacy of complex treatment with remaxol in acute peritonitis.
 Materials and Methods. The authors examined 46 patients with acute peritonitis. The patients were divided into two groups: Groups 1 (comparison, n=26) received standardized treatment, Group 2 (main, n=20) was treated with remaxol. Research methods, in addition to routine ones, included the assessment of kidney functional state, endotoxicosis, and oxidative stress.
 Results. It is revealed that in acute peritonitis, the authors recorded substantial deviations in the functional state of the kidneys, such as endogenous intoxication, and oxidative stress. Maximum imbalance is diagnosed on the 1st day of the early postoperative period. The use of remaxol in the complex therapy of patients with acute peritonitis significantly improves the functional state of the kidneys, thus, optimizing the course of the early postoperative period and reducing the severity of endogenous intoxication. The positive effect of the drug is caused by its ability to manage the oxidative stress, a universal pathogenetic trigger for system and organ damage, including kidneys.
 Conclusions. Remaxol has a nephroprotective effect and improves the course of the early postoperative period.

An EDA-based method for solving electric vehicle charging scheduling problem under limited power and maximum imbalance constraints

Electronic vehicles (EVs) are receiving increasing attention to addressing global warming challenges since fossil fuel is replaced with fuel cell technology. Hence, new challenges arise as demands have increased for using EVs. One of these challenges is the long waiting time of charging EVs spent in queues, especially during peak hours. So, in this study, we aim to propose an efficient method for the electric vehicle charging scheduling problem (EVCSP), which an actual charging station inspires. The most important constraint in this problem is balancing power consumption between charging lines, leading to a limited number of devices that can be charged simultaneously. Also, in this problem, EVs may have interrelationships with each other during the scheduling procedure. So, the estimation of distribution algorithm (EDA) as a competent method in handling the possible relations among decision variables is applied in our proposed hybrid EDA-based solving method. Our proposed method comprises two EDAs, a Markov network-based EDA and a Mallows model-based EDA. It achieves an appropriate schedule and charging line assignment simultaneously while minimizing the total tardiness considering problem constraints. We compared our method with a constraint programming (CP) model and the state-of-art meta-heuristic methods in terms of the objective function value by simulation on a benchmark dataset. Results from the experimental study show significant improvement in solving the introduced EVCSPs.

A Vertiport Design Heuristic to Ensure Efficient Ground Operations for Urban Air Mobility

Urban Air Mobility is a novel concept of transportation with unknown market potential. Even in conservative estimates, thousands of operations could be expected on a single vertiport. This exceeds known heliport operations, which is the most comparable existing mode of transport—by far. Vertiport operations, in particular the dynamics on the airfield, are not well understood; in the following article, we want to address this research gap. By using means of agent-based simulation, the following design drivers were identified: peaks in demand, imbalance between arrivals and departures, pad operations and gate operations. We calculate a practical hourly capacity of 264 movements for our baseline scenario consisting of 4 pads, 12 gates and 20 stand. We are further able to shown that avoiding this peak and staying below a maximum imbalance between arrivals and departures of less than 33 ensures an average passenger delay of less than 3 min. Lastly, we present a parameter study varying the number of pads and gates, the length of approach/departure and boarding/de-boarding and the level of demand. The results of this study are aggregated into a graphical design heuristic displaying the interchangeability of the mentioned aspects.

Changes in the cytokine status in women with chronic liver pathology during reproductive losses in the first trimester

Research objective: to determine the level of serum cytokines in the pregravidar period in women with chronic diseases of the hepatobiliary system and reproductive losses in the first trimester in the anamnesis.Materials and methods. 90 patients of reproductive age with chronic pathology of the hepatobiliary system (liver steatosis and non-alcoholic steatohepatitis) were examined. All patients had spontaneous miscarriages in the early stages of gestation in anamnesis. The research was conducted during the pregravid preparation period. The laboratory research included an additional study of the interleukins (ІL-2, ІL-6, ІL-8, ІL-10) and tumor necrosis factor (TNFα) in the blood serum using enzyme immunoferment assay. 8 female donors were examined to determine the reference norm of cytokines in the blood serum. Results. The cytokine status in patients with chronic pathology of the hepatobiliary system against the background of early miscarriage was characterized by an increase in proinflammatory cytokines (TNFα in 2,29 times more, ІL-2 in 1,46 times, ІL-6 in 1,84 times and ІL-8 in 1,50 times) and anti-inflammatory cytokines (ІL-10 in 1,31 times). The integral indices that are characterizing the oppositional cytokines ratio increased (TNFα/ІL-10, ІL-2/ІL-10 and ІL-6/ІL-10) which indicates an inflammatory process in the body. Minimal changes were registered in patients with signs of steatosis – a moderate increase in proinflammatory cytokines (TNFα is 1,34 times more, ІL-2 in 1,18 times, ІL-6 in 1,33 times and ІL-8 in 1,13 times) and preservation within the reference norm of ІL-10. The maximum imbalance of serum cytokines was observed in the exacerbation of non-alcoholic steatohepatitis – a significant increase in proinflammatory cytokines (TNFα is 3,66 times more, ІL-2 in 1,95 times, ІL-6 in 2,57 times and ІL-8 in 2,18 times) against the background of a moderate increase in ІL-10 (1,30 times). In patients with clinical and laboratory signs of remission of non-alcoholic steatohepatitis a moderate increase in proinflammatory (TNFα is 1,87 times more, ІL-2 in 1,20 times, ІL-6 in 1,61 times and ІL-8 in 1,20 times) and anti-inflammatory (ІL-10 in 1,51 times) cytokines was diagnosed. The analysis of the integral indices of oppositional cytokines showed a tendency to increase their values in patients with liver steatosis and non-alcoholic steatohepatitis in the phase of clinical and laboratory remission. During the period of the non-alcoholic steatohepatitis exacerbation a considerable increase in the studied coefficients was revealed. Conclusions. Changes in the cytokine status are noted in patients with early spontaneous miscarriages in anamnesis and chronic diseases of the hepatobiliary system, which are characterized by the severity of inflammatory reactions and progression of the pathological process in liver. Obtained results can be used to predict miscarriage and be taken into account in the program of drug preparation in the pregravid period.

BBW: a batch balance wrapper for training deep neural networks on extremely imbalanced datasets with few minority samples

In recent years, Deep Neural Networks (DNNs) have achieved excellent performance on many tasks, but it is very difficult to train good models from imbalanced datasets. Creating balanced batches either by majority data down-sampling or by minority data up-sampling can solve the problem in certain cases. However, it may lead to learning process instability and overfitting. In this paper, we propose the Batch Balance Wrapper (BBW), a novel framework which can adapt a general DNN to be well trained from extremely imbalanced datasets with few minority samples. In BBW, two extra network layers are added to the start of a DNN. The layers prevent overfitting of minority samples and improve the expressiveness of the sample distribution of minority samples. Furthermore, Batch Balance (BB), a class-based sampling algorithm, is proposed to make sure the samples in each batch are always balanced during the learning process. We test BBW on three well-known extremely imbalanced datasets with few minority samples. The maximum imbalance ratio reaches 1167:1 with only 16 positive samples. Compared with existing approaches, BBW achieves better classification performance. In addition, BBW-wrapped DNNs are 16.39 times faster, relative to unwrapped DNNs. Moreover, BBW does not require data preprocessing or additional hyper-parameter tuning, operations that may require additional processing time. The experiments prove that BBW can be applied to common applications of extremely imbalanced data with few minority samples, such as the classification of EEG signals, medical images and so on.

Optimized Passive Cell Balancing for Fast Charging in Electric Vehicle

Electric vehicles (EVs) are clean substitutes for conventional vehicles. Battery management system (BMS) is the intelligence behind the EV battery packs. One of the key functions of BMS is cell balancing, which balances the battery cells voltages equally during charging. Most of today’s EVs are adopting a passive cell balancing scheme, which uses fixed dissipative resistors to remove the extra charge from the overcharged cell to balance the charge in all the cells equally. One of the main concerns about the passive balancer is the balancing time. The long balancing time is manageable if the vehicle is charged through conventional charging (5–6 h) system and cell imbalance is minimum. Under fast DC charging scenarios as well as maximum imbalance condition, passive balancing with a fixed resistor is not an optimum solution. Either for fresh cell or aged cell, the passive cell balancing with variable balancing resistor is used based on the balancing current requirement under slow or fast charging scenarios are implemented. The passive system with variable resistor outcome is compared using Matlab-Simscape.

Asymptotic Enumeration of Orientations of a Graph as a Function of the Out-Degree Sequence

We prove an asymptotic formula for the number of orientations with given out-degree (score) sequence for a graph $G$. The graph $G$ is assumed to have average degrees at least $n^{1/3 + \epsilon}$ for some $\epsilon > 0$, and to have strong mixing properties, while the maximum imbalance (out-degree minus in-degree) of the orientation should be not too large. Our enumeration results have applications to the study of subdigraph occurrences in random orientations with given imbalance sequence. As one step of our calculation, we obtain new bounds for the maximum likelihood estimators for the Bradley-Terry model of paired comparisons.

Generation of series of electron acoustic solitary wave pulses in plasma

One-dimensional fluid simulation is used to investigate the generation of electron-acoustic solitary waves (EASWs) in three-species plasma. We consider an unmagnetized collisionless plasma consisting of cold electrons, hot electrons, and ions. The Gaussian perturbations in the equilibrium electron and ion densities are used to excite the waves in the plasma. This simulation demonstrates the generation of a series of EASW pulses in this three-species plasma through the process of wave breaking. We investigate the behavior of the ponderomotive potential, frequency, and force associated with electrons and ions during the process of the wave breaking. We observed that the ponderomotive potential of the hot electron, which is the driving species for the electron acoustic waves, peaks at the time of wave breaking. The variation of the maximum ponderomotive force acting spatially on the leading and trailing edges of the hump in the cold and hot electron and ion fluid densities shows the maximum imbalance in the magnitude of the ponderomotive force acting on both sides of the hot electron density hump at the time of wave breaking. This reveals that the imbalanced ponderomotive force acting on the hot electron fluid is responsible for the breaking of the electron acoustic wave in plasma. Furthermore, it is observed that the wave breaking process occurs at an earlier time if the hot electron temperature is increased.

Thermally Compensated Discontinuous Modulation for MVAC/LVDC Building Blocks of Modular Smart Transformers

Reliability and availability are crucial in smart transformers (ST), and power routing in a modular design can reduce thermal stress of power semiconductors and thereby prevent failures. A desired feature of power routing is the independent control of the thermal stress within the ST architecture, which also includes the maximum unbalanced loading of the medium-voltage side converter. The currently employed algorithms, including the multi-frequency power routing, obtain an inherent coupling of the thermal stress between medium-voltage alternating currents (MVac) building blocks and low-voltage direct current (LVdc) building blocks as well as a limitation in the maximum imbalance for the loading of the MV side converter. For overcoming these limitations, discontinuous pulsewidth modulation is combined with power routing for decoupling the thermal behavior of the MVac and the LVdc building blocks and increasing the maximum achievable imbalance of the MV side converter. The algorithm is analyzed and implemented on an experimental test bench with junction temperature measurement. In addition, a study case is carried out to demonstrate the impact of the proposed method on the lifetime of different building blocks.

Clinical and some biochemical features of rhinosinusitis of different etiology

Identified pathogens, and studied the features of the clinical picture, the level of antioxidant activity, the number of TBA-active products, cytokines, chaperones proteins and antibodies against them in the serum of patients with fungal, viral, bacterial rhinosinusitis (RS) were studied. Most RS of viral nature are caused by rhinoviruses, in turn, the causative agent of bacterial RS, most often acts as a polyflora (S. epidermidis, S. aureus, Pseudomonas aeruginosa). In the group of fungal RS prevailed A. fumigatus. It is noted that a more severe clinical picture in patients bacterial RS; it was manifested by a prolonged course, more pronounced nasal congestion, smell impairment and frequent relapses of the disease. High levels of LPO and a decrease in serum antioxidant activity were established for all studied infectious RS with a maximum imbalance in the LPO-AOP system in fungal forms; shift of the cytokine profile towards pro-inflammatory factors (IL-1b, IL-2, IL-8, IL-6) was registered in bacterial and viral RS and towards the values of anti-inflammatory IL-4 - in fungal RS. The increased amount of chaperone proteins was seen in bacterial RS; high concentration of antibodies against them was noted in fungal and viral RS.

A conditional depreciation balancing strategy for the equitable operation of extended hybrid energy storage systems

Various history life depreciations and energy characteristics of the facilities in the hybrid energy supply system challenge the conventional balancing strategies, which mostly aim to address the state-of-charge imbalance issues. This paper proposes a conditional depreciation balancing strategy to cope with the stated challenge. The conditional depreciation balancing strategy is based on extended hybrid energy storage systems, which consist of supercapacitors, batteries and equivalent battery storage units corresponding to heating systems. An integrated virtual battery model is adopted in the equivalent process of the heating system. The conditional depreciation is innovatively defined to evaluate the operation equitability of the extended hybrid energy storage systems. The equalization of the conditional depreciation is achieved by a multiscale searching algorithm. The proposed conditional depreciation balancing strategy is validated by a hybrid energy supply system of a four-floor building in Shanghai, China. Test results show that the fast dynamic response ability of the supercapacitors and the high energy density of the integrated virtual battery models are utilized fully by the proposed conditional depreciation balancing strategy. The maximum power changing rate of the supercapacitors, integrated virtual battery models and batteries is 0.86 kW/s, 0.03 kW/s, and 0.22 kW/s, respectively. The 24-h charging/discharging energy of the supercapacitors, integrated virtual battery models and batteries is 7.80 kWh, 18.37 kWh and 5.21 kWh, respectively. Compared to the state-of-charge balancing strategy, the proposed conditional depreciation balancing strategy decreases the maximum imbalance coefficient of the energy storage units by 82.74%. The life depreciation rate and the life depreciation cost of the extended hybrid energy storage system decrease by 47.05% and 53.85%, respectively.

Robust silicon 3-dB coupler using inverse engineering based optimization

We propose a scheme to optimize the adiabaticity of silicon 3-dB couplers for broadband operation and good fabrication tolerance. We use the invariant based inverse engineering to optimize the system evolution to be as as adiabatic as possible while ensuring that the resulting device parameters are smooth. Using the inverse engineering based optimization, a 125 µm long silicon 3-dB coupler with a maximum imbalance of 0.8 dB from 1.4 to 1.7 µm and good fabrication tolerance is obtained. The optimized waveguide widths and separation are smooth.

Spontaneous imbalance in the non-hydrostatic Boussinesq equations

Whereas high-frequency waves are valid solutions to the Boussinesq equations in certain limits, their amplitudes are generally observed to be small in large-scale atmospheric and oceanic data. Traditionally, this has led to the development of balance models, reducing the dynamics to only the slow subset. Their solutions, however, can spontaneously generate imbalance in the context of the full equations. To quantify this, we calculate how much energy is transferred from the balanced to the unbalanced part of a turbulent rotating stratified flow that has been initialised to remove high frequencies. We lay out an approach to derive the time evolution of the balanced modes in which their interactions with unbalanced modes are taken into account. This enables us to calculate the budget of balanced (and unbalanced) energy. Our results show that imbalance generation occurs at scales where the Froude and Rossby numbers are still small and the energy spectrum is steep. We find that the scale at which maximum imbalance is generated depends on the peak of the energy spectrum and is invariant to the strength of rotation over the range examined. The unbalanced energy, after being transferred from the balanced component of the flow at larger scales, is cascaded forward and forms a shallow energy spectrum. The steep balanced subrange of the energy spectrum and the shallow subrange cross and form a kink in the total energy spectrum consistent with observed atmospheric and oceanic data. A frequency analysis at different wavenumbers shows that the separation of time scales breaks down at wavenumbers larger than those of maximum imbalance generation, but smaller than the kink of the energy spectrum. Below these scales, there is a single turbulent distribution of frequencies.

A bi-level scheduling model for virtual power plants with aggregated thermostatically controlled loads and renewable energy

With the penetration of renewable energy increasing, the power system requires higher flexibility of power regulation. Virtual power plants can aggregate distributed flexible loads to improve the utilization of distributed renewable energy. In this paper, a bi-level scheduling model for virtual power plants with a large number of distributed thermostatically controlled loads and intermittent renewable energy is established to reduce the net exchange power deviation caused by the forecast error of renewable energy. The upper level optimizes the exchange power curve and reduces the imbalance costs in intraday, while the lower level tracks the optimized power curve in real-time to complete the regulation target. Static and dynamic aggregation method reflecting the regulation characteristics of aggregated thermostatically controlled loads is proposed and applied in lower/upper level, respectively. In addition, a two-step simplified strategy is proposed to solve the mixed integer nonlinear programming in upper level. Simulation results show that the proposed method can reduce the maximum imbalance power, and it is not affected by parameters heterogeneity, which is suitable for virtual power plants with diversified users.

Spectral imbalance in the inertial range dynamics of decaying rotating turbulence.

Direct numerical simulations of homogeneous decaying turbulence with background rotation show the existence of a systematic and significant imbalance between the non-linear energy cascade to small scales and its dissipation. By starting the decay from a statistically stationary and weakly rotating turbulent state, where the dissipation and the energy flux are approximately equal, the data show a growing imbalance between the two until a maximum is reached when the dissipation is about twice the energy flux. This dichotomy of behaviors during decay is reminiscent of the nonequilibrium and the equilibrium regions previously reported for nonrotating turbulence [Valente and Vassilicos, Phys. Rev. Lett. 108, 214503 (2012)PRLTAO0031-900710.1103/PhysRevLett.108.214503]. Note, however, that for decaying rotating turbulence the classical scaling of the dissipation rate ε∝u^{'3}/L (where u^{'} and L are the root mean square fluctuating velocity and the integral length scale, respectively) does not appear to hold during decay, which may be attributed to the effect of the background rotation on the energy cascade. On the other hand, the maximum energy flux holds the scaling Π_{max}∝u^{'3}/L in the initial stage of the decay until the maximum imbalance is reached.

High selectivity tunable filtering power divider based on liquid crystal technology for microwave applications

A novel electrically tunable filtering power divider, based on liquid crystal (LC) technology, is designed and experimentally demonstrated in this paper. Using low-cost T-shaped inverted-microstrip structures integrated with two dual-mode open-loop resonators, the tunable power divider possesses bandpass-filtering frequency response. Moreover, transitions between inverted-microstrip and microstrip structures are specifically designed at the I/O ports for the self-packaged. The experimental results indicate that the central frequency can be tuned from 5.75 to 6.25 GHz, i.e. a relative tuning range of 8.3%, the 3-dB bandwidth is 6.8 ± 0.2% over the whole tuning range, and the maximum amplitude and phase imbalance are less than 0.8 dB and 2.5°, respectively. In addition, the proposed filtering power divider has three transmission zeros to improve the frequency selectivity.

Stability investigation of the steady motions of an isolated system, carrying out plane motion

The paper investigates the conditional stability of steady motions of a flat model of an isolated system consisting of a rotating LB, material point, which creates its static imbalance, and two identical mathematical pendulums, mounted on the longitudinal axis of the LB and moving in the plane of the static imbalance, the relative motion of which is prevented by the viscous resistance. It was found that in the case where there is imbalance and pendulums can eliminate it with a certain reserve, there is one basic motion; in the absence of imbalance, there is a one-parameter family of basic motions; in the case of maximum imbalance, which can be eliminated by pendulums, there is one basic motion, but it generates pseudo-family of basic motions. Also, it was found that some basic motions are conditionally asymptotically stable, if they, or family, or pseudo-family of basic motions are isolated. In the absence of imbalance, the presence of a single zero root of the characteristic equation does not affect the stability of the one-parameter family of basic motions, and is responsible for the transition from one to another steady motion of the family. In the case of maximum imbalance, the presence of a single zero root of the characteristic equation does not affect the stability of the basic motion, and is responsible for the transition from one to another steady motion of pseudo-family. Transients, depending on the system parameters can be aperiodic or oscillatory-damped. It was found that the side motions are unstable.