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Purpose To describe the prevalence of refractive error (RE) and its association with other environmental and health factors among population aged ≥50 years who lived in Gilan, Iran in 2014.Methods In this population-based cross-sectional study, 3281 individuals aged ≥50 years living in Gilan for at least 6 months were enrolled. The prevalence of different types of REs including myopia (spherical equivalent (SE)≤-0.50D), high myopia (SE ≤ -6.00D), hyperopia (SE≥ + 0.50D), high hyperopia (SE≥ + 3.00D), astigmatism (cylinder < -0.50D) and high astigmatism (cylinder < -2.25D) were determined. Anisometropia was defined as the SE difference of ≥1.00D between the two eyes. Associated factors including age, body mass index (BMI) and education were also studied.Results 2587 eligible individuals (58% female subjects) with the mean age of 62.6 ± 8.8 years participated (87.6% response rate). The prevalence of myopia, hyperopia and astigmatism was 19.2%, 48.6% and 57.4%, respectively. 3.6% high hyperopia, 0.5% high myopia and 4.5% high astigmatism were identified. The positive simultaneous effects3 of older age (Odds Ratio (OR) = 3.14), nuclear (OR = 1.71) and posterior subcapsular (OR = 1.61) cataracts as well as the negative effects of higher levels of education (OR = 0.28) were obtained on myopia. Higher BMI was found as a risk factor for hyperopia (OR = 1.67), while older patients were less likely to be hyperopic (OR = 0.31).Conclusion Higher incidence of myopia and astigmatism was found in patients aged over 70 years. It was also found that patients at older ages who suffered with cataracts were at a higher risk of myopia, while elderly people with greater BMI were at a higher risk of hyperopia.

While the filling stage has the least time during the metal casting process, its influence on the casting quality can be remarkable. In gravity casting, the design and dimensions of the filling system determine the filling rate, metal velocity, and the possibility of surface turbulence, where the reliability of casting is mainly impressed by these parameters. In this study, finding an appropriate filling system for a hollow cylinder is examined by investigating the effect of the ingate size, shape, and geometry on the flow characteristics of the molten metal. Simulations are performed investigating the initial filling stages and their repercussions. Three different bottom-gating filling systems are proposed with rectangular, fan, and ring ingate shapes. To compare the filling pattern, metal velocity, and air entrainment of three different filling systems, ProCAST, a CFD simulation software, is used. Results indicated that fan ingate shape successfully introduced less turbulent flow than rectangular ingate shape, causing a reduction in air entrainment. Moreover, results showed that using ring ingate, with sufficient total ingate cross section and taking advantage of the uphill metal flow, can reduce metal velocity entering the cavity as well as eliminate air entrainment.

Background: Cardiovascular diseases are leading causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Cardiac involvement in SLE can often go undetected. Three-dimensional (3D) speckle tracking echocardiography (STE) is a noninvasive imaging technique that can assess the function of the heart’s ventricles in an accurate and reproducible way. This makes it an attractive option for detecting early signs of heart disease in SLE patients. By identifying these subclinical cardiac abnormalities, 3D-STE may help reduce the negative impact of cardiovascular diseases in SLE population. Therefore, this study aimed to compare the left ventricular (LV) function between patients with SLE compared to age- and gender-matched controls using two-dimensional (2D) and 3D-STE. Results: The current study found no significant differences in left ventricle ejection fraction, left ventricle end-diastolic volume, left ventricle end-systolic volume, left ventricle end-diastolic mass, and left ventricle end-systolic mass between the two groups. However, the SLE group exhibited a significantly lower LV global longitudinal strain (GLS) compared to the control group according to all types of echocardiographic assessments, including 3D and 2D long-axis strain, apical 2-chamber, and apical 4-chamber assessments (all Pvalues &lt; 0.05). Furthermore, a good inter-rater reliability and intra-rater reliability were observed regarding the LVGLS measurement with 3D-STE. Additionally, the study identified a significant correlation between LVGLS and SLE duration (r(50) = 0.46, P&lt; 0.001). The use of prednisolone and nephrology disorders was also found to impact LVGLS measurements. Conclusions: Despite a normal LVEF in patients with SLE, LVGLS measurements indicated that LV systolic dysfunction was observed more frequently in SLE patients compared to their healthy counterparts. Therefore, advanced 3D-STE techniques may be useful in identifying subtle abnormalities in LV function in SLE patients.

Patients with multiple sclerosis (MS) are at higher risk of having infections due to receiving disease modifying therapies. The current study was conducted among Iranian MS patients who had experienced at least one episode of COVID-19 infection in order to evaluate the effects of COVID-19 vaccination on symptoms of their infection. Data on demographic information, MS characteristics, COVID-19 infection details, and vaccination status were collected. Statistical analyses, were performed to evaluate the association between vaccination and symptoms of COVID-19 infection.

This study proposes a novel loss function for neural network models that explores the topological structure of stock realized volatility (RV) data by adding Wasserstein Distance (WD). The study shows that the proposed loss statistically significantly improves the forecast accuracy of neural network models for magnitude-dependent error measures, for example, Root Mean Square Error (RMSE) and Mean Absolute Error (MAE), but not necessarily for relative error measures, such as Quasi-likelihood (QLIKE). Additionally, this research provides user-friendly open-source code for researchers and practitioners to implement the proposed loss function efficiently and quickly.

This study investigates the Topological Tail Dependence (TTD) theory’s applicability to individual stock volatility and high dimensions. Utilizing a comprehensive dataset from the S&P 100, the research employs various methodologies to test the predictions and implications of the TTD theory. The theory’s main prediction of Wasserstein Distance’s predictive utility, particularly in nonlinear models during volatile periods, is confirmed. The research suggests extending the TTD theory’s application to various financial instruments and incorporating dynamic topological features to enhance understanding market dynamics. This study validates the TTD theory for individual stocks and highlights the necessity of topological considerations in financial modeling, promising advancements in financial econometrics and risk management strategies.

This study was conducted to evaluate the potential of the bleached bagasse, cellulose, and nanofiber cellulose to remove methylene blue (MB) from aqueous solution. The morphology of adsorbents surface and their functional groups were examined by using scanning electron microscope and Fourier transform infrared spectroscopy techniques, respectively. In a batch mode study at 25°C temperature, the effects of initial dye concentration, contact time, adsorbent dose, and solution pH on adsorption performance were investigated. The results showed that the percent of MB removal increases by increasing pH and also by increasing sorbent dosage and decreasing initial dye concentration. The adsorption kinetics and equilibrium data were in good agreement with the pseudo-second-order kinetic model and Freundlich adsorption isotherm, respectively. The removal of MB was better and more effective with cellulose and cellulose nanofiber as compared with the bleached bagasse. The regeneration of cellulose and nanofiber cellulose loaded with MB was investigated using electrochemical method under different operating conditions. The results showed that the electrochemical process efficiency is more than 60% for regeneration adsorbents.

As part of the revelations about the NSA activities, the notion of interdiction has become known to the public: the interception of deliveries to manipulate hardware in a way that backdoors are introduced. Manipulations can occur on the firmware or at hardware level. With respect to hardware, FPGAs are particular interesting targets as they can be altered by manipulating the corresponding bitstream which configures the device. In this paper, we demonstrate the first successful real-world FPGA hardware Trojan insertion into a commercial product. On the target device, a FIPS-140-2 level 2 certified USB flash drive from Kingston, the user data are encrypted using AES-256 in XTS mode, and the encryption/decryption is processed by an off-the-shelf SRAM-based FPGA. Our investigation required two reverse-engineering steps, related to the proprietary FPGA bitstream and to the firmware of the underlying ARM CPU. In our Trojan insertion scenario, the targeted USB flash drive is intercepted before being delivered to the victim. The physical Trojan insertion requires the manipulation of the SPI flash memory content, which contains the FPGA bitstream as well as the ARM CPU code. The FPGA bitstream manipulation alters the exploited AES-256 algorithm in a way that it turns into a linear function which can be broken with 32 known plaintext–ciphertext pairs. After the manipulated USB flash drive has been used by the victim, the attacker is able to obtain all user data from the ciphertexts. Our work indeed highlights the security risks and especially the practical relevance of bitstream modification attacks that became realistic due to FPGA bitstream manipulations.

Block ciphers are arguably the most important cryptographic primitive in practice. While their security against mathematical attacks is rather well understood, physical threats such as side-channel analysis (SCA) still pose a major challenge for their security. An effective countermeasure to thwart SCA is using a cipher representation that applies the threshold implementation (TI) concept. However, there are hardly any results available on how this concept can be adopted for block ciphers with large (i.e., 8-bit) Sboxes. In this work we provide a systematic analysis on and search for 8-bit Sbox constructions that can intrinsically feature the TI concept, while still providing high resistance against cryptanalysis. Our study includes investigations on Sboxes constructed from smaller ones using Feistel, SPN, or MISTY network structures. As a result, we present a set of new Sboxes that not only provide strong cryptographic criteria, but are also optimized for TI. We believe that our results will find an inspiring basis for further research on high-security block ciphers that intrinsically feature protection against physical attacks.

Evoked by the increasing need to integrate side-channel countermeasures into security-enabled commercial devices, evaluation labs are seeking a standard approach that enables a fast, reliable and robust evaluation of the side-channel vulnerability of the given products. To this end, standardization bodies such as NIST intend to establish a leakage assessment methodology fulfilling these demands. One of such proposals is the Welch’s ttest, which is being put forward by Cryptography Research Inc. and is able to relax the dependency between the evaluations and the device’s underlying architecture. In this work, we deeply study the theoretical background of the test’s different flavors and present a roadmap which can be followed by the evaluation labs to efficiently and correctly conduct the tests. More precisely, we express a stable, robust and efficient way to perform the tests at higher orders. Further, we extend the test to multivariate settings and provide details on how to efficiently and rapidly carry out such a multivariate higher-order test. Including a suggested methodology to collect the traces for these tests, we point out practical case studies where different types of ttests can exhibit the leakage of supposedly secure designs.

When evaluating the face in thirds, the upper face, midface, and lower face, one may assume the lateral the temple, midface, and lateral mandible as the pillars of these subdivisions. Many of our facial aesthetic procedures address these regions, including the lateral brow lift, midface lift, and lateral face lift. As the use of facial fillers has advanced, more emphasis is placed on the correction of the temples, midlateral face, and lateral jaw line. This article is dedicated to these facial aesthetic pillars.

Supplemental Digital Content is available in the text.

Supplemental Digital Content is available in the text.

To protect Field-Programmable Gate Array (FPGA) designs against Intellectual Property (IP) theft and related issues such as product cloning, all major FPGA manufacturers offer a mechanism to encrypt the bitstream that is used to configure the FPGA. From a mathematical point of view, the employed encryption algorithms (e.g., Advanced Encryption Standard (AES) or 3DES) are highly secure. However, it has been shown that the bitstream encryption feature of several FPGA families is susceptible to side-channel attacks based on measuring the power consumption of the cryptographic module. In this article, we present the first successful attack on the bitstream encryption of the Altera Stratix II and Stratix III FPGA families. To this end, we analyzed the Quartus II software and reverse engineered the details of the proprietary and unpublished schemes used for bitstream encryption on Stratix II and Stratix III. Using this knowledge, we demonstrate that the full 128-bit AES key of a Stratix II as well as the full 256-bit AES key of a Stratix III can be recovered by means of side-channel attacks. In both cases, the attack can be conducted in a few hours. The complete bitstream of these FPGAs that are (seemingly) protected by the bitstream encryption feature can hence fall into the hands of a competitor or criminal—possibly implying system-wide damage if confidential information such as proprietary encryption schemes or secret keys programmed into the FPGA are extracted. In addition to lost IP, reprogramming the attacked FPGA with modified code, for instance, to secretly plant a hardware Trojan, is a particularly dangerous scenario for many security-critical applications.

Abstract: Since the introduction of the first side-channel analyses in academia about 15 years ago, several physical attacks have been presented that exploit side-channel leakages to break implementations of cryptographic algorithms. This article deals with the same physical property of electronic devices, but focuses on the art of tailoring it for constructive uses. More precisely, two scenarios, i.e., hardware Trojans and IP watermarking, are illustrated in which the designer of an electronic circuit can add functionality by considering side channels as part of the available design space. Both applications use the same concept, i.e., deliberately leaking a secret through a side channel while keeping the introduced side channel hidden from adversaries and attackers. This article provides a broad overview of the existing works for both applications and should serve as a comprehensible introduction to the underlying field of research. This includes many subtle details that have not been discussed in literature yet, including existing shortcomings and possible improvements to the existing works. The solutions summarized in this article provide general guidelines for theorists and practitioners to use side channels constructively to achieve designs that are robust against detection and removal. Furthermore, we present an entirely new design of a Trojan side-channel. This architecture demonstrates the potential of a Trojan side-channel that is neatly tailored to the targeted implementation. The new design removes all non-invasive starting points a third party could use to analyze or get access to the secret-channel.

The bioheat transfer with phase change in biological tissues during the freezing process is simulated by the dual phase lag conduction heat transfer model. A numerical algorithm based on the enthalpy method is established to solve the solidification of biological tissues. The linearly temperature-dependent enthalpy (non-isothermal phase change) is considered here. The results of the parabolic heat conduction model for a slice of cucumber are compared with the experimental data. A comparison between dual phase lag and hyperbolic solutions with small values of relaxation times is applied in order to verify the corresponding parabolic solutions accuracy of the dual phase lag and hyperbolic solutions. The heating source effect owing to blood perfusion and metabolic heat on the heat transfer in a biological tissue subject to freezing process is studied. The relaxation time has an important influence on the transient temperature and temperature gradient. A major discrepancy among bioheat transfer models is found for zones closer to the cooling boundary. The heat source term, owing to blood flow and metabolism in a phase change problem in the biological tissue, has a significant influence on thermal effects of the subject tissue.

This paper investigates the COVID-19 outbreak, explains the policies adopted by governments, and examines the side effects of social distancing on the global economy and international finance. Causal loop diagrams are used to explain the interlinkages amongst the important variables and show the outbreak follows the pattern of a reinforcing loop. Governments strive to balance this loop by adopting a set of policies, of which social distancing has left a tremendous negative impact on the global economy. The side effects of this policy are highlighted in three categories: short-term, midterm, and long-term by explaining the reinforcing loops that require time to get stimulated. The short-term loops result in demand and supply shocks in any economy, and if this policy stays effective for a longer period, the midterm loops get activated, leading to corporate and government debt crises. When the pandemic duration extends, the long-term side effects appear with a deflationary recession and a banking crisis. The quickness of moving from one category to another in an economy depends on the financial strength of firms and their government. Finally, this paper anticipates some changes in future business caused by the pandemic, which can bring insights for managers.

A case of traumatic perforation of the uterus with subsequent omental implantation in the endometrial cavity clinically presenting 16 years later as an endometrial lipoma is discussed. This case should alert clinicians to the existence of such a complication to be included in their differential diagnosis of lipomatous lesions of the uterus.