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Woven flax-carbon hybrid polyamide biocomposites offer a blend of carbon fibers' mechanical strength and flax's environmental advantages, potentially developing material applications. This study investigated their thermal behavior, degradation kinetics, and durability to water uptake and relative humidity exposure and compared them with pure flax and carbon composites with the same matrix. The hybrid composite exhibited intermediate water/moisture absorption levels between pure flax and carbon composites, with 7.2% water absorption and 3.5% moisture absorption. It also displayed comparable thermal degradation resistance to the carbon composite, effectively maintaining its weight up to 300 °C. Further analysis revealed that the hybrid composite exhibited a decomposition energy of 268 kJ/mol, slightly lower than the carbon composite's value of 288.5 kJ/mol, indicating similar thermal stability. Isothermal lifetime estimation, employing the activation energy (Ed) and degree of conversion facilitated by the Model Free Kinetics method, indicated a 41% higher service life of the hybrid laminate at room temperature compared to the carbon laminate. These insights are crucial for understanding the industrial applications of these materials without compromising durability. [ABSTRACT FROM AUTHOR]

Fiber hybridization is suggested to enhance the properties of fiber‐reinforced composites. Regarding the matrix, thermoplastic alternatives to conventional thermosets are needed to balance mechanical performance and sustainability. We combined woven flax and carbon fibers with a polyamide 11 matrix into a hybrid biocomposite and studied its manufacturing process as well as its impact, tensile, and damping properties. Mechanical damage was investigated using scanning electron microscopy and X‐ray computed tomography. Hybridization significantly improved the tensile properties: 233% higher modulus and 432% higher strength than pure flax composites and 19% higher failure strain than pure carbon composites. Additionally, the hybrid composites exhibited a positive hybrid effect with respect to the impact resistance, characterized by higher displacement at maximum impact force and occurrence of combined damage mechanisms. Although the damping behavior of the hybrid composites remained inferior to that of pure flax composites, their damping factor was 20% higher than that of pure carbon composites. These results provide valuable insights into the mechanical performance of carbon‐flax hybrid composites. Highlights: Enhanced mechanical performance and impact resistance in woven flax‐carbon/PA11 hybrid biocomposite compared to nonhybrid reference composites.Superior tensile modulus and strength of hybrid biocomposite than pure flax fiber composite, and greater failure strain than pure carbon fiber composite.A positive hybridization effect in impact properties with a greater displacement at maximum force and higher dissipated impact energy, indicating enhanced ductility and fracture toughness.Improved damping behavior in hybrid biocomposite compared to the pure carbon composite. [ABSTRACT FROM AUTHOR]

Hybridizing carbon-fiber-reinforced polymers with natural fibers could be a solution to prevent delamination and improve the out-of-plane properties of laminated composites. Delamination is one of the initial damage modes in composite laminates, attributed to relatively poor interlaminar mechanical properties, e.g., low interlaminar strength and fracture toughness. This study examined the interlaminar bond strength, flexural properties, and hardness of carbon/flax/polyamide hybrid bio-composites using peel adhesion, three-point bending, and macro-hardness tests, respectively. In this regard, interlayer hybrid laminates were produced with a sandwich fiber hybrid mode, using woven carbon fiber plies (C) as the outer layers and woven flax fiber plies (F) as the inner ones (CFFC) in combination with a bio-based thermoplastic polyamide 11 matrix. In addition, non-hybrid carbon and flax fiber composites with the same matrix were produced as reference laminates to investigate the hybridization effects. The results revealed the advantages of hybridization in terms of flexural properties, including a 212% higher modulus and a 265% higher strength compared to pure flax composites and a 34% higher failure strain compared to pure carbon composites. Additionally, the hybrid composites exhibited a positive hybridization effect in terms of peeling strength, demonstrating a 27% improvement compared to the pure carbon composites. These results provide valuable insights into the mechanical performance of woven carbon–flax hybrid bio-composites, suggesting potential applications in the automotive and construction industries. [ABSTRACT FROM AUTHOR]

Approximately 6 million youth aged 12 to 20 consume alcohol monthly in the United States. The effect of alcohol consumption in adolescence on behavior and cognition is heavily researched; however, little is known about how alcohol consumption in adolescence may alter brain function, leading to long-term developmental detriments. In order to investigate differences in brain connectivity associated with alcohol use in adolescents, brain networks were constructed using resting-state functional magnetic resonance imaging data collected by the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) from 698 youth (12–21 years; 117 hazardous drinkers and 581 no/low drinkers). Analyses assessed differences in brain network topology based on alcohol consumption in eight predefined brain networks, as well as in whole-brain connectivity. Within the central executive network (CEN), basal ganglia network (BGN), and sensorimotor network (SMN), no/low drinkers demonstrated stronger and more frequent connections between highly globally efficient nodes, with fewer and weaker connections between highly clustered nodes. Inverse results were observed within the dorsal attention network (DAN), visual network (VN), and frontotemporal network (FTN), with no/low drinkers demonstrating weaker connections between nodes with high efficiency and increased frequency of clustered nodes compared to hazardous drinkers. Cross-sectional results from this study show clear organizational differences between adolescents with no/low or hazardous alcohol use, suggesting that aberrant connectivity in these brain networks is associated with risky drinking behaviors. [ABSTRACT FROM AUTHOR]

Carbon fiber-reinforced polymer (CFRP) composite materials are widely used in engineering applications, but their production generates a significant amount of waste. This paper aims to explore the potential of incorporating mechanically recycled aerospace prepreg waste in thermoplastic composite materials to reduce the environmental impact of composite material production and promote the use of recycled materials. The composite material developed in this study incorporates a bio−based thermoplastic polymer, polyamide 11 (PA11), as the matrix material and recycled aerospace prepreg waste quasi-one-dimensionally arranged as reinforcement. Mechanical, thermal, and thermomechanical characterizations were performed through tensile, flexural, and impact tests, as well as differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Compared to previous studies that used a different recycled CFRP in the shape of rods, the results show that the recycled prepregs are a suitable reinforcement, enhancing the reinforcement-matrix adhesion and leading to higher mechanical properties. The tensile results were evaluated by SEM, and the impact tests were evaluated by CT scans. The results demonstrate the potential of incorporating recycled aerospace prepreg waste in thermoplastic composite materials to produce high-performance and sustainable components in the aerospace and automotive industries. [ABSTRACT FROM AUTHOR]

Using the finite difference method in the time domain, the present study deals with the effect of the presence of aluminum and gold nanorods on the quantities of the short-circuit current density and the absorption in the ITO/PEDOT:PSS/P3HT:PCBM/ZnO/Al organic solar cell. The nanorods, made of an aluminum cylinder and two golden caps, are located in a hexagonal pattern inside the P3HT:‌PCBM layer and at the border with ZnO. During the simulation, the standard spectral pattern of the sun AM1.5 has been used in the spectral range of 300–1200 nm. Calculations have shown that the presence of nanorods significantly improves the values of the aforementioned quantities. This is especially noticeable in the range of high wavelengths. According to the results, when the height of the nanoparticles changes, one can see changes in the optimal thickness of the highest short-circuit current density and the absorption in a way that the P3HT:PCBM active layer is optimal in thicknesses of 150, 200, and 250 nm at nanorod heights of 50, 100, and 150 nm, respectively. The calculations in different conditions show that the short-circuit current density and the absorption under the optimal thickness of the active layer is 150 nm, the height of the cylinder is 50 nm, the radius of the cylinder is 20 nm, and the curvature radius of both caps is 4 nm. [ABSTRACT FROM AUTHOR]

Objective: The ongoing COVID-19 pandemic has been associated with clinical signs characterized by fever, fatigue and cough. Our study aimed to assess the efficacy of a Persian medicine formulation, lavender syrup, as an add-on to standard care in patients with mild to moderate COVID-19. Materials and Methods: In this clinical trial which was conducted in Gorgan (Iran), 84 male and female COVID-19 outpatients were randomly allocated to either lavender syrup receiving 9 ml/twice/day for 21 days with standard conventional care or control groups. The primary objectives were to assess the improvement of clinical symptoms, while the secondary objectives were treatment satisfaction and anxiety levels which were evaluated once a week for 3 weeks. Results: Out of 84 participants, 81 were analyzed (41 in the addon group). The comparison between groups for cough severity and anosmia showed a higher reduction in the lavender group. The effect size was 0.6 for cough relief. Other symptoms and the Hamilton total score decreased in both groups with no statistically significant differences between the groups. The lavender group showed greater patients' satisfaction score. Conclusion: Adjunctive therapy with lavender syrup could reduce cough and improve the quality of life in patients with COVID-19 patients. [ABSTRACT FROM AUTHOR]

Small and Medium-sized Enterprises play a significant role in most economies by contributing to job creation and economic growth. A majority of such merchants rely on business financing, and thus, financial institutions and investors need to assess their performance before making decisions on business loans. However, current methods of predicting merchants' future performance involve their private internal information, such as revenue and customer base, which cannot be shared without potentially exposing critical information. To address this problem, we first propose a novel approach to predicting merchants' future performance using credit card transaction data. Specifically, we construct a merchant network, regarding customers as bridges between merchants, and extract features from the constructed network structure for prediction purposes. Our study results demonstrate that the performance of machine learning models with features extracted from our proposed network is comparable to those with conventional revenue- and customer-based features, while maintaining higher privacy levels when shared with third-party organizations. Our approach offers a practical solution to privacy concerns over data and information required for merchants' performance prediction, enabling safe data-sharing among financial institutions and investors, helping them make more informed decisions on allocating their financial resources while ensuring that merchants' sensitive information is kept confidential. [ABSTRACT FROM AUTHOR]

This paper puts forward a transient numerical model for thermoacoustic energy convertors using Rott's equations combined with electrical circuit analogy. To enhance the accuracy of model outcomes, the lumped element values are updated at each time step as a function of temperature. Accordingly, a nonlinear temperature distribution is obtained along the hot core. The developed numerical approach is in line with the experimental results of a standing wave thermoacoustic engine. Based on this method, the temperature variations along the stack and the impact of stack material on start-up time and onset temperature are numerically investigated. Additionally, the onset temperature profiles are calculated and presented comparatively for the numerical and experimental results. The start-up time of spontaneous oscillations is calculated for the standing wave system. Consequently, the best geometry that quickly reaches sustained oscillations can be selected using this model. Examining the temperature profile during the start-up and damping process highlights a temperature difference between these two processes. This is calculated as 35 K in the numerical solution and measured as 38 K in the experiment for a standing wave engine. Observations show that using a material with lower thermal conductivity in the stack section can reduce the onset-damping temperature difference. The novel approach described here shows potential in capturing the onset-damping behavior of thermoacoustic systems efficiently. [ABSTRACT FROM AUTHOR]

The increasing use of carbon fiber and epoxy resin composite materials yields an increase in the amount of waste. Therefore, we present a solution consisting of composites manufactured by hot pressing, employing polyamides (either PA11 or PA12) and a mechanically recycled carbon fiber-reinforced polymer (CFRP) as reinforcement. The main objectives are to study the manufacturing of those composites, to evaluate the fiber distribution, and to perform a mechanical, dynamical, and thermomechanical characterizations. The X-ray micro-computed tomography (μCT) shows that the fibers are well-distributed, maintaining a homogeneous fiber volume fraction across the material. The variability in the results is typical of discontinuous fiber composites in which the fibers, although oriented, are not as homogeneously distributed as in a continuous fiber composite. The mechanical and dynamic properties barely differ between the two sets of composites. A dynamic-mechanical analysis revealed that the glass transition temperature (Tg) increases slightly for both composites, compared to the polymers. These results illustrate the viability of the recycling and reuse route for preventing the deterioration of carbon fibers and promoting the subsequent reduction in the environmental impact by employing a thermoplastic matrix. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing (AM) technology has been utilized in many industries including automotive, aerospace, and medical. AM Ti6Al4V (Ti64) alloy is highly noticed for production of medical instruments such as dental implants and the machining process is mostly needed during the production or post-processing of these components. Numerical model, as a powerful tool, can be efficiently used for analyzing the machining process. A customized model was employed using a user-written subroutine in this work to evaluate machinability and microstructural changes in cryogenic machining of AM Ti64 alloy. For this purpose, the microstructural changes were simulated as the new numerical outputs. The numerical results of cutting forces, temperature, nano-hardness, and alpha lamellae thickness (grain size) were successfully verified by corresponding experiments from literature. Then, the impact of tool geometry (including rake and clearance angles, cutting edge radius, and nose radius) on the machinability performance was examined. It was found that, the variation of clearance and rake angles were more effective on depth of the hardened layer compared to the other parameters. Thickness of alpha lamellae phase near the machined surface and depth of the affected layer by nano-hardness changes were changed from 0.9 to 1.58 µm, and from 18 to 40 µm, respectively. Overall, it was concluded that the variation of insert positioning made by tool holder (change in rake and clearance angles) was an effective parameter on the process outputs when machining AM Ti64 alloy. [ABSTRACT FROM AUTHOR]

This study presents a novel control strategy for managing nonlinear systems in the presence of mismatched uncertainties. Dealing with the uncertainties that do not satisfy the so‐called matching conditions is an ongoing issue in control engineering. In this regard, and for the first time, a disturbance observer (DO)‐based hybrid control system, which considers robustness as well as control signal optimality, is developed in this article. For this purpose, and with the aim of robustly managing uncertain nonlinear systems and achieving optimized control effort, an optimal control law based on the state‐dependent Riccati equation is integrated with a DO‐based second‐order sliding mode controller. The Lyapunov stability theory is applied to verify the asymptotic stability of the designed control system. Computer simulations are performed to demonstrate the efficacy and the superiority of our novel controller over two other existing methods (DO‐based sliding mode control [SMC] and DO‐based adaptive SMC). The simulation results show that the presented method is capable of managing uncertain nonlinear systems robustly and with much less control effort than the two mentioned methods. [ABSTRACT FROM AUTHOR]

This study uses a comprehensive control approach to deal with the trajectory tracking problem of a two-flexible-link manipulator subjected to model uncertainties. Because the control inputs of two-flexible-link manipulators are less than their state variables, the proposed controller should be able to tackle the stated challenge. Practically speaking, there is only a single control signal for each joint, which can be used to suppress link deflections and control joint trajectories. To achieve this objective, a novel optimal robust control scheme, with an updated gain under the adaptive law, has been developed in this work for the first time. In this regard, a nonsingular terminal sliding mode control approach is used as the robust controller and a control Lyapunov function is used as the optimal control law, to benefit from the advantages of both methods. To systematically deal with system uncertainties, an adaptive law is used to update the gain of nonsingular terminal sliding mode control. The advantage of this approach over the existing methods is that it not only can robustly and stably control an uncertain nonlinear system against external disturbances but also can optimally solve a quadratic cost function (e.g. minimization of control effort). The Lyapunov stability theory has been applied to verify the stability of the proposed approach. Moreover, to show the superiority of this method, the computer simulation results of the proposed method have been compared with those of an adaptive sliding mode control scheme. This comparison shows that the presented approach is capable of optimizing the control inputs while achieving the stability of the examined two-flexible-link manipulator in the presence of model uncertainties and external disturbances. [ABSTRACT FROM AUTHOR]

In this paper, we present a deliberate bit flipping (DBF) coding scheme for binary two-dimensional (2-D) channels, where specific patterns in channel inputs are the significant cause of errors. The idea is to eliminate a constrained encoder and, instead, embed a constraint into an error correction codeword that is arranged into a 2-D array by deliberately flipping the bits that violate the constraint. The DBF method relies on the error correction capability of the code being used so that it should be able to correct both deliberate errors and channel errors. Therefore, it is crucial to flip minimum number of bits in order not to overburden the error correction decoder. We devise a constrained combinatorial formulation for minimizing the number of flipped bits for a given set of harmful patterns. The generalized belief propagation algorithm is used to find an approximate solution for the problem. We evaluate the performance gain of our proposed approach on a data-dependent 2-D channel, where 2-D isolated-bits patterns are the harmful patterns for the channel. Furthermore, the performance of the DBF method is compared with classical 2-D constrained coding schemes for the 2-D no isolated-bits constraint on a memoryless binary symmetric channel. [ABSTRACT FROM AUTHOR]

Objective: Epilepsy is a common neurological disorder, the history of which dates back to thousands of years ago. Avicenna (980-1037 AD) is a famous Persian scholar who considered different types of epilepsy and their specific treatments. His book Al-Qanun fi al-Tibb was taught in Europe for several years. Along with explaining the diseases occurring in various body organs, the book describes neurological and neuropsychological conditions such as epilepsy METHODS: This article is a review of the book Al-Qanun fi al-Tibb and some of the traditional Persian medicine sources, including Kāmil al-Sināa al Tibbiya and Makhzan-O-L Advieh, on uterine epilepsy, its etiology, clinical manifestations and treatments. Also, articles related to this topic in the field of traditional Persian medicine or historical articles have been searched for in Google Scholar search engine or PubMed database.Results: Avicenna categorizes the causes of epilepsy into two main groups: those caused by brain diseases and those associated with the diseases of other organs. He believed that the stomach, the spleen, the maraqq, the uterus, or other body organs influence the brain and can cause epilepsy. In uterine epilepsy, the primary pathology lies with the uterus and can affect the brain. This condition occurs due to the retention of the menses or semen.Conclusion: In this historical article, we intend to explain Avicenna's viewpoint on uterine epilepsy. We suggest further studies on this topic, for example, to evaluate the frequency of epilepsy in patients with the retention of the menses or the semen. [ABSTRACT FROM AUTHOR]

Analyzing the structure and function of the brain from a network perspective has increased considerably over the past two decades, with regional subnetwork analyses becoming prominent in the recent literature. However, despite the fact that the brain, as a complex system of interacting subsystems (i.e., subnetworks), cannot be fully understood by analyzing its constituent parts as independent elements, most studies extract subnetworks from the whole and treat them as independent networks. This approach entails neglecting their interactions with other brain regions and precludes identifying potential compensatory mechanisms outside the analyzed subnetwork. In this study, using simulated and empirical data, we show that the analysis of brain subnetworks within the context of their whole‐brain networks, that is, including their interactions with other brain regions, can yield different outcomes when compared to analyzing them as independent networks. We also provide a multivariate mixed‐effects modeling framework that allows analyzing subnetworks within the context of their whole‐brain networks, and show that it can better disentangle global (whole‐brain) and local (subnetwork) differences when compared to standard t‐test analyses. T‐test analyses may produce misleading results in identifying complex global and local level differences. The provided multivariate model is an extension of a previously developed model for global, system‐level hypotheses about the brain. The modified version detailed here provides the same utilities as the original model—quantifying the relationship between phenotypes and brain connectivity, comparing brain networks among groups, predicting brain connectivity from phenotypes, and simulating brain networks—but for local, subnetwork‐level hypotheses. [ABSTRACT FROM AUTHOR]

Cavitation erosion poses a significant challenge in fluid systems like hydraulic turbines and ship propellers due to pulsed pressure from collapsing vapor bubbles. To combat this, various materials and surface engineering methods are employed. In this study, nano and micro scale particles of silicon carbide (SiC) or boron carbide (B4C) were incorporated as reinforcement at 6% and 12% ratios, owing to their exceptional resistance to abrasive wear and high hardness. Microparticles were incorporated to assess the damage incurred during the tests in comparison to nanoparticles. Wear tests were conducted on both bulk samples and coated aluminum sheets with a 1mm of composite. Additionally, cavitation tests were performed on coated aluminum tips until stability of mass loss was achieved. The results indicated a distinct wear behavior between the coatings and the bulk samples. Overall, wear tended to be higher for the coated samples with nanocomposites than bulk, except for the nano-composite material containing 12% SiC and pure resin. With the coatings, higher percentages of nanometric particles correlated with increased wear. The coefficient of friction remained within the range of 0.4 to 0.5 for the coatings. Regarding the accumulated erosion in the cavitation tests for 100 min, it was observed that for all nanocomposite materials, it was lower than in pure resin. Particularly, the composite with 6% B4C was slightly lower than the rest. In addition, the erosion rate was also lower for the composites. [ABSTRACT FROM AUTHOR]

Complex brain networks formed via structural and functional interactions among brain regions are believed to underlie information processing and cognitive function. A growing number of studies indicate that altered brain network topology is associated with physiological, behavioral, and cognitive abnormalities. Graph theory is showing promise as a method for evaluating and explaining brain networks. However, multivariate frameworks that provide statistical inferences about how such networks relate to covariates of interest, such as disease phenotypes, in different study populations are yet to be developed. We have developed a freely available MATLAB toolbox with a graphical user interface that bridges this important gap between brain network analyses and statistical inference. The modeling framework implemented in this toolbox utilizes a mixed‐effects multivariate regression framework that allows assessing brain network differences between study populations as well as assessing the effects of covariates of interest such as age, disease phenotype, and risk factors on the density and strength of brain connections in global (i.e., whole‐brain) and local (i.e., subnetworks) brain networks. Confounding variables, such as sex, are controlled for through the implemented framework. A variety of neuroimaging data such as fMRI, EEG, and DTI can be analyzed with this toolbox, which makes it useful for a wide range of studies examining the structure and function of brain networks. The toolbox uses SAS, R, or Python (depending on software availability) to perform the statistical modeling. We also provide a clustering‐based data reduction method that helps with model convergence and substantially reduces modeling time for large data sets. [ABSTRACT FROM AUTHOR]

• Forecasts disaggregated sales when there are no historical sales. • Integrates the literature on forecasting and spatial/gravity models. • Estimate attraction based on all points of interest and not only commercial ones. • Estimates customer stocks and transient flows among cities' neighborhoods. • Disaggregates a forecast using a hybrid probabilistic gravitational approach. Whenever companies plan to enter new geographical areas, they need disaggregated sales in each location. To make such predictions, sales time series or final customers' data in geographical disaggregation are necessary. However, for most companies, such datasets are unavailable or impractical. The manuscript has two main goals. One focal problem is how to disaggregate an aggregate sales prediction with no historical proportions. The other is how to improve spatial models using Point of Interest (POI) data. To solve these problems, we combine two literature streams — spatial marketing and sales forecasting — and propose a new hybrid probabilistic approach: Gravitational Sales Prediction (GSP). Our approach uses POI data to estimate area attraction, customer stocks, and flows to predict sales proportions. We later use these proportions to disaggregate an aggregate forecast. GSP is validated using sales data from two countries and more than ten economic segments. When compared to a strong benchmark that relies on past sales proportions, GSP exceeded expectations by achieving not only a similar performance to the benchmark but also outperforming it in some locations. It showed the most promising results in the middle level of aggregation. The result is a powerful and flexible approach that can be embedded in any decision support system. [ABSTRACT FROM AUTHOR]

Latino immigrants that work on farms experience chronic exposures to potential neurotoxicants, such as pesticides, as part of their work. For tobacco farmworkers there is the additional risk of exposure to moderate to high doses of nicotine. Pesticide and nicotine exposures have been associated with neurological changes in the brain. Long-term exposure to cholinesterase-inhibiting pesticides, such as organophosphates and carbamates, and nicotine place this vulnerable population at risk for developing neurological dysfunction. In this study we examined whole-brain connectivity patterns and brain network properties of Latino immigrant workers. Comparisons were made between farmworkers and non-farmworkers using resting-state functional magnetic resonance imaging data and a mixed-effects modeling framework. We also evaluated how measures of pesticide and nicotine exposures contributed to the findings. Our results indicate that despite having the same functional connectivity density and strength, brain networks in farmworkers had more clustered and modular structures when compared to non-farmworkers. Our findings suggest increased functional specificity and decreased functional integration in farmworkers when compared to non-farmworkers. Cholinesterase activity was associated with population differences in community structure and the strength of brain network functional connections. Urinary cotinine, a marker of nicotine exposure, was associated with the differences in network community structure. Brain network differences between farmworkers and non-farmworkers, as well as pesticide and nicotine exposure effects on brain functional connections in this study, may illuminate underlying mechanisms that cause neurological implications in later life. [ABSTRACT FROM AUTHOR]

Scenario techniques are to be used in the field of energy for development of planning and as well as management. Large numbers of studies and researches have been reported by the Shell, IEA (International Energy Agency), WEC (World Energy Council), etc. based on the scenario techniques for visualizing of energy status. This study presents a Scenario-Based Model based on assumption about Iran׳s energy future. For this purpose, a conceptual framework and implementation of the method were presented. Afterwards, four scenarios were generated namely: Orange cake, Green horizon, Critical point, Wishful thinking. Scenarios in three-dimensional (political, science and technology (S&T) and environmental) aspects of energy were presented. Results showed that the green horizon scenario has a high convergence for long-term occurrence probability. The three-dimensional distance among the scenarios in the mentioned dimensions indicates that the main variables that shape the future of Iran׳s energy would act in coordination regardless of the category they are placed in. [ABSTRACT FROM AUTHOR]

Many studies propose methods for finding the best location for new stores and facilities, but few studies address the store closing problem. As a result of the recent COVID-19 pandemic, many companies have been facing financial issues. In this situation, one of the most common solutions to prevent loss is to downsize by closing one or more chain stores. Such decisions are usually made based on single-store performance; therefore, the under-performing stores are subject to closures. This study first proposes a multiplicative variation of the well-known Huff gravity model and introduces a new attractiveness factor to the model. Then a forward–backward approach is used to train the model and predict customer response and revenue loss after the hypothetical closure of a particular store from a chain. In this research the department stores in New York City are studied using large-scale spatial, mobility, and spending datasets. The case study results suggest that the stores recommended being closed under the proposed model may not always match the single store performance, and emphasizes the fact that the performance of a chain is a result of interaction among the stores rather than a simple sum of their performance considered as isolated and independent units. The proposed approach provides managers and decision-makers with new insights into store closing decisions and will likely reduce revenue loss due to store closures. [ABSTRACT FROM AUTHOR]

Pesticide exposure has been associated with adverse cognitive and neurological effects. However, neuroimaging studies aimed at examining the impacts of pesticide exposure on brain networks underlying abnormal neurodevelopment in children remain limited. It has been demonstrated that pesticide exposure in children is associated with disrupted brain anatomy in regions that make up the default mode network (DMN), a subnetwork engaged across a diverse set of cognitive processes, particularly higher-order cognitive tasks. This study tested the hypothesis that functional brain network connectivity/topology in Latinx children from rural farmworker families (FW children) would differ from urban Latinx children from non-farmworker families (NFW children). We also tested the hypothesis that probable historic childhood exposure to pesticides among FW children would be associated with network connectivity/topology in a manner that parallels differences between FW and NFW children. We used brain networks from functional magnetic resonance imaging (fMRI) data from 78 children and a mixed-effects regression framework to test our hypotheses. We found that network topology was differently associated with the connection probability between FW and NFW children in the DMN. Our results also indicated that, among 48 FW children, historic reports of exposure to pesticides from prenatal to 96 months old were significantly associated with DMN topology, as hypothesized. Although the cause of the differences in brain networks between FW and NFW children cannot be determined using a cross-sectional study design, the observed associations between network connectivity/topology and historic exposure reports in FW children provide compelling evidence for a contribution of pesticide exposure on altering the DMN network organization in this vulnerable population. Although longitudinal follow-up of the children is necessary to further elucidate the cause and reveal the ultimate neurological implications, these findings raise serious concerns about the potential adverse health consequences from developmental neurotoxicity associated with pesticide exposure in this vulnerable population. [ABSTRACT FROM AUTHOR]

Two-dimensional magnetic recording 2-D (TDMR) is a promising technology for next generation magnetic storage systems based on a systems-level framework involving sophisticated signal processing at the core. The TDMR channel suffers from severe jitter noise along with electronic noise that needs to be mitigated during signal detection and recovery. Recently, we developed noise prediction-based techniques coupled with advanced signal detectors to work with these systems. However, it is important to understand the role of harmful patterns that can be avoided during the encoding process. In this paper, we investigate the Voronoi-based media model to study the harmful patterns over multitrack shingled recording systems. Through realistic quasi-micromagnetic simulation studies, we identify 2-D data patterns that contribute to high media noise. We look into the generic Voronoi model and present our analysis on multitrack detection with constrained coded data. We show that the 2-D constraints imposed on input patterns result in an order of magnitude improvement in the bit-error rate for the TDMR systems. The use of constrained codes can reduce the complexity of 2-D intersymbol interference (ISI) signal detection, since the lesser 2-D ISI span can be accommodated at the cost of a nominal code rate loss. However, a system must be designed carefully so that the rate loss incurred by a 2-D constraint does not offset the detector performance gain due to more distinguishable readback signals. [ABSTRACT FROM PUBLISHER]

Reviewing historical medical manuscripts shows that neurological disorders have been previously described in the Islamic Golden Age. Ibn Sina, also known as Avicenna (980-1037 AD), was one of the most renowned scientists during this period. He widely practiced medicine, especially those disorders related to neurology, neurosurgery, and psychiatry in conventional medicine. In his extant book al-Qānūn fī al-Tibb (the Canon of Medicine), he claimed that some types of brain diseases can be related to the “marāqq” and called them marāqq-related disorders. From Avicenna’s viewpoint, “marāqq” is considered a membranous structure in the abdomen. Ibn Sina has illustrated the association between the “marāqq” and the brain through some direct and indirect pathways. As a result, some disturbances in the “marāqq” can influence the brain, which can contribute to the pathogenesis of a number of brain diseases. Accordingly, those patients who regularly had gastrointestinal discomforts experienced a higher prevalence of headache, melancholia, and epilepsy. This study aimed to explore the relationship between abdominal and brain diseases from Avicenna’s viewpoint. Furthermore, the definition, clinical manifestation, and therapeutic strategies of marāqq-related disorders were described. [ABSTRACT FROM AUTHOR]

In the present paper, dynamic pull-in instability and free vibration characteristics of circular higher-order shear deformable nanoplates subjected to hydrostatic and electrostatic forces are studied including surface stress effect. For this purpose, Eringen's nonlocal elasticity continuum in conjunction with the Gurtin-Murdoch elasticity theory is incorporated into the classical higher-order shear deformation plate theory to develop size-dependent plate model able to consider both of small scale and surface stress effects. The non-classical governing differential equations are then discretized along with simply supported and clamped edge supports by employing generalized differential quadrature (GDQ) method. To evaluate the size-dependent pull-in voltage of nanoplates, the hydrostatic-electrostatic actuation is assumed to be calculated by neglecting the fringing field effects and utilizing the parallel plate approximation. It is demonstrated that the pull-in instability occurs at lower voltages for nanoplates with higher values of nonlocal parameters. Moreover, it is found that surface stress effect can increase or decrease the pull-in voltage of nanoplates which depends on the sign of surface elastic constants. [ABSTRACT FROM AUTHOR]

In this paper, a threaded tapered pin tool was employed to fabricate a 2-pass friction stir welded (FSWed) joint. To investigate the benefits of nano-sized SiC particles on microstructural and mechanical properties of the joint, the experiment was repeated while SiC particles had been inserted along the joint line. In another joint, a square pin tool was applied in the second pass to evaluate the effectiveness of switching pin geometry between passes on the aforementioned properties. Microstructural features including grain size, second phase particles and reinforcement distribution were examined via optical and scanning electron microscopy (SEM) techniques. In addition to satisfactory connections between SiC particles and the matrix, the most homogenous particles distribution was observed in the specimen FSWed with both pin tools. This observation was further supported by atomic force microscopy (AFM) examination. Additionally, the foregoing joint demonstrated the maximum tensile strength which was synonymous with its smallest grain size. During tensile testing, SiC-free joint and SiC-reinforced ones fractured from stir zone (SZ) and base metal, respectively. Moreover, SiC-free joint showed necking phenomenon. SEM results showed that the SiC-reinforced specimens possessed ductile fracture morphologies. On the other hand, SiC-free specimen showed a quasi-cleavage fracture mode confirming its moderate percent elongation. In the meantime, SiC-reinforced specimens exhibited superior hardness level to SiC-free specimen. [ABSTRACT FROM AUTHOR]

Photodecolorization of bromothymol blue (BTB) aqueous solution using supported ZnO onto clinoptilolite nanoparticles (NCP) under Hg lamp irradiation was studied. NCP was prepared by a mechanical method using a planetary ball mill. ZnO supported samples (ZnO–NCP) were obtained by calcinations at 450 °C for 12 h followed by ion exchanging of the parent NCP with zinc(II) nitrate aqueous solutions (0.1, 0.2, 0.3 and 0.5 M) for 24 h. Raw and modified samples were characterized by XRD, FT-IR, DRS, TEM, SEM and BET. The degradation extent was monitored by UV–vis absorption as well as COD. The decolorization kinetics was fitted well to the Langmuire–Hinselwood first order rate law. [ABSTRACT FROM AUTHOR]

In the current paper, dynamic stability analysis of microbeams subjected to piezoelectric voltage is presented in which the microbeam is integrated with piezoelectric layers on the lower and upper surfaces. Both of the flutter and divergence instabilities of microbeams with clamped-clamped and clamped-free boundary conditions are predicted corresponding to various values of applied voltage. To take size effect into account, the classical Timoshenko beam theory in conjunction with strain gradient elasticity theory is utilized to develop nonclassical beam model containing three additional internal length scale parameters. By using Hamilton's principle, the higher-order governing differential equations and associated boundary conditions are derived. Afterward, generalized differential quadrature method is employed to discretize the size-dependent governing differential equations along with clamped-clamped and clamped-free end supports. The critical piezoelectric voltages corresponding to various values dimensionless length scale parameter are evaluated and compared with those predicted by the classical beam theory. It is revealed that in the case of clamped-free boundary conditions, the both of flutter and divergence instabilities occur. However, for the clamped-clamped microbeams, only divergence instability takes place. [ABSTRACT FROM AUTHOR]

The vibration analysis of a micro-pump diaphragm is presented. A piezoelectric micro-pump is studied. For this purpose, a dynamic model of the micro-pump is derived. The micro-pump diaphragm is modeled as circular double membranes, a piezoelectric one as actuator and a silicon one for representing the membrane for pumping action. The damping effect of the fluid is introduced into the equations. Vibration analysis is established by explicitly solving the dynamic model. The natural frequencies and mode shapes are calculated. The orthogonality conditions of the system are discussed. To verify the results, the finite-element micro-pump model is developed in ANSYS software package. The results show that the two methods are well comparable. [ABSTRACT FROM AUTHOR]

The goal of this work is to use the supported ZnO–FeO onto nano-clinoptilolite particles (NCP) in the photocatalytic degradation of the pollutants present in a fish ponds wastewater as a real sample under solar irradiation. Ion exchanging of the prepared ball-milling NCP in aqueous solution containing Zn(II) and Fe(II) cations and calcinations of the ion exchanged material at 450 °C led to the formation of ZnO–FeO/NCP catalyst. The raw and modified NCP samples were characterized by XRD, FT-IR, DRS and SEM. The degradation extent of the pollutants was calculated using UV–vis absorption of samples before and after irradiation process. The optimum values for the affecting experimental parameters were obtained as: 0.1 g L −1 of the photocatalyst, initial concentration of wastewater and pH 8.3. [ABSTRACT FROM AUTHOR]

One of the symbols of developed countries is high tech industries. High tech industries have a large margin. One of the priorities of developing countries is the progress in this type of industries. The decisions about priority of developing an industry are so hard that seems it should be seen from different perspectives. This research is focused on decision and policy making in priority of high tech industries in Iran. Two MCDM methods are applied in this research for decision making in this area. SWARA for evaluating and weighting criteria and COPRAS for evaluating and ranking alternatives are applied. Eleven experts from different fields participated in this research to make decision with SWARA and COPRAS. Four high tech industries including Biomedical Micro Electromechanical Systems (BioMEMS), Nano Technology, Biotechnology, and Biomedical Engineering were selected for this research. These industries were selected based on the potential of Iran. Final result shows that Nanotechnology is at the top of priorities in Iran. Authors believe that this methodology can be useful in other issues in this and other areas of research. [ABSTRACT FROM AUTHOR]

Abstract: In the current research, the role of SiC nano-particles in improving the mechanical properties of friction stir welded (FSWed) 7075 aluminum alloy is investigated. To this end, friction stir welding (FSW) was conducted at 1250rpm and 40mm/min. The experiment carried out with and without incorporating SiC nano-particles along the joint line. Cross-sectional microstructures of the joints were characterized employing optical and scanning electron microscopy (SEM). Results achieved through X-ray diffraction (XRD) confirmed the presence of SiC powders. Moreover, it was discovered that the volume fraction of the reinforcement particles was 20%. Along with an excellent bonding between SiC nano-particles and aluminum matrix, SEM photograph demonstrated a good dispersion of SiC reinforcements. Atomic force microscopy (AFM) results were also in tight agreement with the recent SEM microstructure. Thanks to the presence of SiC nano-particles, tensile strength, percent elongation, fatigue life, and toughness of the joint improved tremendously. The fracture morphologies were in good agreement with corresponding ductility results. [Copyright &y& Elsevier]

Highlights: [•] AA7075/SiC nano-composite was fabricated in stir zone via FSW. [•] Using triangular pin tool resulted in the highest tensile strength. [•] In exception of four-flute cylindrical specimens, all specimens fractured from base metal. [•] Threaded tapered specimen showed the most uniform distribution of SiC particles. [ABSTRACT FROM AUTHOR]

Highlights: [•] AA7075/SiC nano-composite developed employing friction stir welding technique. [•] 1250rpm and 40mm/min were the optimum welding speeds. [•] Increasing rotational speed resulted in improved powders dispersion. [•] An excellent bonding between reinforcement and the matrix was observed. [•] UTS and ductility improved by up to 31% and 76.1% due to grain size refinement associated with SiC nano-particles. [ABSTRACT FROM AUTHOR]

Abstract: Iran as a major oil producing country has increasingly paid attention to the non-fossil energy resources, in particular to renewable energy sources for its longer term energy plans. In this regard, 11 projects pertaining to solar energy are being utilized or carried out by Iran׳s Ministry of Energy. The total photovoltaic power installed in 2004 was 14,020MW. This rate reached 67MW by the end of 2010. Further, two geothermal projects are being constructed in Ardabil Province at present. By the end of 2010, the Meshkinshahr geothermal power plant project revealed a progress rate equal to 50%. Similarly, the package construction project in Ardabil revealed a 32% progress. Due to financial hardship in the Fourth Development Program, the completion of these projects was extended to the end of the Fifth Development Program. The nameplate power of biogas power plants in Iran is 1.860MW the total installed capacity is 1.665MW. According to Strategy Document of Fuel Cell Technology Development (Approved by the government in 2004), Iran has revealed good progress in fuel cell projects. Private sectors have already signed contracts to build more than 600MW of biomass systems and 500MW of new wind energy developments. The nominal power of the wind parks that can be erected in the available sites with remarkable wind potential in Iran is approximately 6500MW, employing wind turbines of 60,000MW nominal power. The estimated mean annual capacity factor of these wind parks is 33%. [Copyright &y& Elsevier]

The rapid increase in the application of carbon fiber reinforced polymer (CFRP) composite materials represents a challenge to waste recycling. The circular economy approach coupled with the possibility of recovering carbon fibers from CFRP waste with similar properties to virgin carbon fibers at a much lower cost and with lower energy consumption motivate the study of CFRP recycling. Mechanical recycling methods allow the obtention of chopped composite materials, while both thermal and chemical recycling methods aim towards recovering carbon fibers. This review examines the three main recycling methods, their processes, and particularities, as well as the reuse of recycled carbon fibers in the manufacture of new composite materials. [ABSTRACT FROM AUTHOR]

Abstract: Design and synthesis of a nonlinear time-varying and non-minimum phase supersonic flight vehicle longitudinal dynamics control for g-commands output tracking are presented. Differential geometric approach utilized to outline system relative degree and unstable internal dynamics explored based on the vehicle dynamics transformation into a nonlinear normal form. Unstable internal dynamics are then invoked to identify ideal state reference profiles leading to a desired output-tracking problem. Compensated internal dynamics converged to a solution on the system center manifold for ideal internal dynamics asymptotically. Finally, sliding mode control employed based on an appropriate sliding manifold to track the reference input while being robust against uncertainties. Simulation results are performed and effectiveness of the designed approach demonstrated. [Copyright &y& Elsevier]

Objectives We investigated the effect of natural honey on body weight and some blood biochemical indices of diabetic subjects. Methods Forty-eight diabetic type 2 patients were randomly assigned into two groups: the honey group received oral natural honey for 8 weeks, and the control group did not take honey. Before the onset of the study (week 0) and after 8 weeks, weight measurements were taken and fasting blood samples were drawn. Results After adjustment for the baseline values, there were no significant differences in the fasting blood sugars between the two groups. Body weight, total cholesterol, low-density lipoprotein-cholesterol and triglyceride decreased (P = 0.000), and high-density lipoprotein-cholesterol increased significantly (P < 0.01) in honey group. The levels of hemoglobin A1C increased significantly in this group (P < 0.01). Conclusion The results of this study demonstrate that 8-week consumption of honey can provide beneficial effects on body weight and blood lipids of diabetic patients. However, since an increase in the hemoglobin A1C levels was observed, cautious consumption of this food by diabetic patients is recommended. [ABSTRACT FROM AUTHOR]

Chemically speaking, polyamide 11 (PA11) and polyamide 12 (PA12) have a similar backbone, differing only in one carbon. From an origin point of view, PA11 is considered a bioplastic polyamide composed from renewable resources, compared to oil-based PA12. Each of them has a number of advantages over the other, which makes their selection a challenging issue. Depending on the target application, diverse assessments and comparisons are needed to fulfill this mission. The current study addresses this research gap to characterize and compare PA11 and PA12 manufactured by the hot press technique in terms of their mechanical, thermal and durability properties for the first time, demonstrating their potential for future works as matrices in composite materials. In this regard, different characterization techniques are applied to the hot-pressed polymer sheets, including X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The mechanical performance of the PA11 and PA12 sheets is compared based on tensile tests and shore hardness measurement. The durability behavior of these two polyamides is evaluated in water and relative humidity conditions at different aging times. The experimental results show the ductile behavior of PA12 with respect to the quasi-brittle PA11. Both have a relatively small water and moisture gain: 1.5 wt% and 0.8 wt%, respectively. The higher crystallinity of PA12 (2.1 times more than PA11) with γ-phase is one of the leading parameters to achieve better mechanical and durability properties. The FTIR spectra displayed slight acid hydrolysis. Accordingly, absorbed water or moisture does not cause plasticization; thus, neither hardness nor dimension changes. [ABSTRACT FROM AUTHOR]

The investigation of renewable and recyclable materials becomes more critical every day due to the high levels of waste and carbon emissions and their impact on the environment. The use of eco-friendly materials, such as natural fibers and bioplastics, is increasingly important, and their use is always more popular. The aim of this research is to evaluate the changes in properties of composite materials made of Poly-Butyl-Succinate (PBS), a biodegradable thermoplastic matrix, and carbon fiber when some layers of carbon fiber are replaced by some layers of flax fiber to create a hybrid composite; in order to obtain a material more environmentally friendly with similar mechanical properties. To modify the flax fiber's surface energy and improve the wettability with the PBS matrix, an Atmospheric Pressure Plasma Torch (APPT) treatment was performed. The fibers' surfaces were characterized by measuring the contact angle; the contact angle values confirmed the wettability and accordingly, adhesion increased after plasma treatment. Different experiments were performed after substituting carbon fibers to evaluate the changes in the composite material's mechanical and thermal properties: tensile test, three-point bending test, impact tests and differential scanning calorimetry. Replacing the carbon fiber core layer with one or two flax fiber layers did not compromise the thermal stability. It led to the manufacturing of a hybrid composite with improved mechanical properties and higher impact resistance. • Development of hybrid biocomposite from PBS biodegradable polymer, carbon and flax fibers with hot press technique. • Impact resistance improvement by replacing carbon fiber for flax fiber in biopolymer composites. • Improvement of mechanical properties with substitution of one carbon fiber layer with one or two flax fiber layers. [ABSTRACT FROM AUTHOR]

Abstract: An optimal strategy based on minimum control effort with terminal position and velocity constraints is developed for an exoatmospheric interceptor in order to generate effective intercept for fixed-interval propulsive maneuvers. It is then integrated with sliding-mode control theory to derive a robust optimal guidance law. In addition, this guidance law is generalized for intercepting an arbitrarily time-varying target maneuver. The new guidance method''s robustness against disturbances and good miss distance performance are proved by the second method of Lyapunov and simulation results. The presented guidance law is simple to implement in practical applications and requires less acceleration command in comparison to optimal guidance law. [Copyright &y& Elsevier]

Because of the high demand for carbon fiber reinforced polymer (CFRP) materials across all industries, the reuse and/or recycling of these materials (rCFRP) is necessary in order to meet the principles of the circular economy, including recycling and reuse. The objective of this study is to estimate the lifespan of thermoplastic matrix composite materials reinforced with waste materials (CFRP), which undergo only a mechanical cutting process. This estimation is carried out through the thermal decomposition of polymers, including polymer matrix composite materials, which is a complex process due to the numerous reactions involved. Some authors calculate these kinetic parameters using thermogravimetric analysis (TGA) as it is a quick method, and it allows the identification of gases released during decomposition, provided that the equipment is prepared for it. This study includes a comparison between polyamides 11 and 12, as well as between polyamide composite materials with carbon fiber (CF) and polyamides reinforced with CF/epoxy composite material. The latter is treated with plasma to improve adhesion with polyamides. The behavior of weight as a function of temperature was studied at speeds of 3, 6, 10, 13, 17, and 20 °C/min, finding stability of the polyamides up to a temperature of 400 °C, which was consistent with the analysis by mass spectroscopy, where gas evolution is evident after 400 °C. The estimation of the lifespan was carried out using two different methods including the Toop equation and the free kinetics model (MFK). The energy of the decomposition process was determined using the MFK model, which establishes the energy as a function of the degree of conversion. It is estimated that at 5% decomposition, mechanical properties are lost. [ABSTRACT FROM AUTHOR]

Objective: The effect of lavender syrup on COVID-19-induced olfactory dysfunction (OD) has been assessed in this study. Materials and Methods: This pilot clinical trial was conducted in Gonbad-E-Kavoos (Golestan province, Iran). Twenty-three outpatients with COVID-19 and OD in lavender group took 9 ml of lavender syrup/bid for 3 weeks along with the standard COVID-19 treatments and 20 patients in control group took only standard COVID-19 treatments. The severity of OD was assessed by the visual analogue scale (VAS). Data analysis was performed by Friedman and Mann-Whitney tests using SPSS software. Results: The mean± standard deviation of age was 36.6±9.1, and 42.6±10.4 years (p=0.05), and the duration of symptoms was 7.4±3.5, and 7.5±3.4 days (p=0.98) in the lavender and control group, respectively. The VAS score for OD decreased from 6.8±3.04 to 0.26±0.86 in the lavender group and from 5.3±3.4 to 1±2.61 in the control group. Although, VAS for OD was significantly decreased in both groups (p<0.001), the amount of VAS decrease was 6.6±2.9 scores in the lavender group, and 4.3±4 in the control group (p=0.03). No side effects were observed in the lavender group. Conclusion: The present study showed that lavender syrup is an effective treatment for COVID-19-induced OD. It is suggested to conduct further studies with larger sample size. [ABSTRACT FROM AUTHOR]

Background: Data on the epidemiology of inflammatory bowel disease (IBD) in the Middle East are scarce. We aimed to describe the clinical phenotype, disease course, and medication usage of IBD cases from Iran in the Middle East. Methods: We conducted a cross-sectional study of registered IBD patients in the Iranian Registry of Crohn's and Colitis (IRCC) from 2017 until 2022. We collected information on demographic characteristics, past medical history, family history, disease extent and location, extra-intestinal manifestations, IBD medications, and activity using the IBD-control-8 questionnaire and the Manitoba IBD index, admissions history, history of colon cancer, and IBD-related surgeries. Results: In total, 9746 patients with ulcerative colitis (UC) (n = 7793), and Crohn's disease (CD) (n = 1953) were reported. The UC to CD ratio was 3.99. The median age at diagnosis was 29.2 (IQR: 22.6,37.6) and 27.6 (IQR: 20.6,37.6) for patients with UC and CD, respectively. The male-to-female ratio was 1.28 in CD patients. A positive family history was observed in 17.9% of UC patients. The majority of UC patients had pancolitis (47%). Ileocolonic involvement was the most common type of involvement in CD patients (43.7%), and the prevalence of structuring behavior was 4.6%. A prevalence of 0.3% was observed for colorectal cancer among patients with UC. Moreover,15.2% of UC patients and 38.4% of CD patients had been treated with anti-tumor necrosis factor (anti-TNF). Conclusion: In this national registry-based study, there are significant differences in some clinical phenotypes such as the prevalence of extra-intestinal manifestations and treatment strategies such as biological use in different geographical locations. [ABSTRACT FROM AUTHOR]

Two-dimensional magnetic recording (TDMR) is a promising technology for boosting areal densities (ADs) using sophisticated signal processing algorithms within a systems framework. The read/write channel architectures have to effectively tackle 2-D inter-symbol interference (ISI), 2-D synchronization errors, media and electronic noise sources, as well as thermal asperities resulting in burst erasures. The 1-D low-density parity check (LDPC) codes are well studied to correct large 1-D burst errors/erasures. However, such 1-D LDPC codes are not suitable for correcting 2-D burst errors/erasures due to the 2-D span of errors. In this paper, we propose construction of a native 2-D LDPC code to effectively correct 2-D burst erasures. We also propose a joint detection and decoding engine based on the generalized belief propagation algorithm to simultaneously handle 2-D ISI, as well as correct bit/burst errors for TDMR channels. This paper is novel in two aspects: 1) we propose the construction of native 2-D LDPC codes to correct large 2-D burst erasures and 2) we develop a 2-D joint signal detection-decoder engine that incorporates 2-D ISI constraints, and modulation code constrains along with LDPC decoding. The native 2-D LDPC code can correct >20% more burst erasures compared with the 1-D LDPC code over a 128 $\times $ 256 2-D page of detected bits. Also, the proposed algorithm is observed to achieve a signal-to-noise ratio gain of >0.5 dB in bit error rate performance (translating to 10% increase in ADs around the 1.8 Tb/in2 regime with grain sizes of 9 nm) as compared with a decoupled detector-decoder system configuration over a small 2-D LDPC code of size 16 $\times $ 16. The efficacy of our proposed algorithm and system architecture is evaluated by assessing AD gains via simulations for a TDMR configuration comprising of a 2-D generalized partial response over the Voronoi media model assuming perfect 2-D synchronization. [ABSTRACT FROM PUBLISHER]

Avicenna has introduced a type of headache and its related treatment called I uda al-Bu rani i (critical headache), in the I Fa l fi A naf a - uda al-Ka'in bi-l-Mosharakat i (section of types of participatory headaches) [[2]]. The critical stage of a disease named I Bu ran i (crisis) is the days in the course of some acute illnesses usually occurring in the climax of the disease that is accompanied by severe and sudden appearance of some symptoms and signs. [Extracted from the article]