Deterministic creation of stationary entangled states by dissipation

We propose a practical physical system for creation of a stationary entanglement by dissipation without employing the environment engineering techniques. The system proposed is composed of two perfectly distinguishable atoms, through their significantly different transition frequencies, with only one atom addressed by an external laser field. We show that the arrangement would easily be realized in practice by trapping the atoms at the distance equal to the quarter-wavelength of a standing-wave laser field and locating one of the atoms at a node and the other at the successive antinode of the wave. The undesirable dipole-dipole interaction between the atoms, that could be large at this small distance, is adjusted to zero by a specific initial preparation of the atoms or by a specific polarization of the atomic dipole moments. Following this arrangement, we show that the dissipative relaxation can create a stationary entanglement on demand by tuning the Rabi frequency of the laser field to the difference between the atomic transition frequencies. The laser field dresses the atom and we identify that the entangled state occurs when the frequency of one of the Rabi sidebands of the driven atom tunes to frequency of the undriven atom. It is also found that this system behaves as a cascade open system where the fluorescence from the dressed atom drives the other atom with no feedback.Comment: Published versio

H∞ State Estimation for BAM Neural Networks With Binary Mode Switching and Distributed Leakage Delays Under Periodic Scheduling Protocol

Research and Development Office Ministry of Education Kingdom of Saudi Arabia (Grant Number: HIQI-2-2019); National Natural Science Foundation of China (Grant Number: 61903254)

Effect of verapamil on glycemic control in type 2 diabetic hypertensive patients in Saudi Arabia : a quasi experimental study

Background: Type 2 diabetes is a common chronic disease that continues to increase in prevalence globally and is a major healthcare burden. Diabetes and hypertension frequently occur concurrently, and the use of antihypertensive agents is common in diabetic patients. One antihypertensive agent, verapamil, has tentatively shown potentially positive effects on glycemic control in assorted pre-clinical models. Aim: To evaluate the effect of verapamil on glycemic control in hypertensive type 2 diabetic patients. Methods: Type 2 diabetic hypertensive patients were recruited from King Fahad Medical City, Riyadh, KSA, to receive oral verapamil therapy. Blood pressure and glycometabolic parameters, including fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), C-peptide, and homeostatic model assessment insulin resistance (HOMA-IR), were monitored at baseline and after 6 months of verapamil therapy. Results: Thirty-five patients (16 male, 19 female) with a mean age of 57.2 years were recruited. The use of verapamil was associated with non-significant decreases in HbA1c, FPG, C-peptide, and HOMA-IR. However, a sub-group of 17 participants showed a decrease in HbA1c that was ≥0.5%. Univariate logistic regression showed that baseline BMI, HOMA-IR, and C-peptide were significantly (P < 0.05) associated with HbA1c reductions of ≥0.5%. Conclusion: Verapamil is metabolically neutral and allows the stabilization of glycometabolic parameters in type 2 diabetic individuals. Additional research exploring the mechanism behind the variable response to verapamil therapy is warranted

The emergence of macroscopic currents in photoconductive sampling of optical fields

Photoconductive field sampling enables petahertz-domain optoelectronic applications that advance our understanding of light-matter interaction. Despite the growing importance of ultrafast photoconductive measurements, a rigorous model for connecting the microscopic electron dynamics to the macroscopic external signal is lacking. This has caused conflicting interpretations about the origin of macroscopic currents. Here, we present systematic experimental studies on the signal formation in gas-phase photoconductive sampling. Our theoretical model, based on the Ramo–Shockley-theorem, overcomes the previously introduced artificial separation into dipole and current contributions. Extensive numerical particle-in-cell-type simulations permit a quantitative comparison with experimental results and help to identify the roles of electron-neutral scattering and mean-field charge interactions. The results show that the heuristic models utilized so far are valid only in a limited range and are affected by macroscopic effects. Our approach can aid in the design of more sensitive and more efficient photoconductive devices

Secure and dynamic access control for the Internet of Things (IoT) based traffic system

Today, the trend of the Internet of Things (IoT) is increasing through the use of smart devices, vehicular networks, and household devices with internet-based networks. Specifically, the IoT smart devices and gadgets used in government and military are crucial to operational success. Communication and data sharing between these devices have increased in several ways. Similarly, the threats of information breaches between communication channels have also surged significantly, making data security a challenging task. In this context, access control is an approach that can secure data by restricting unauthorized users. Various access control models exist that can effectively implement access control yet, and there is no single state-of-the-art model that can provide dynamicity, security, ease of administration, and rapid execution all at once. In combating this loophole, we propose a novel secure and dynamic access control (SDAC) model for the IoT networks (smart traffic control and roadside parking management). Our proposed model allows IoT devices to communicate and share information through a secure means by using wired and wireless networks (Cellular Networks or Wi-Fi). The effectiveness and efficiency of the proposed model are demonstrated using mathematical models and discussed with many example implementations.</jats:p

Transient field-resolved reflectometry at 50-100 THz

Transient field-resolved spectroscopy enables studies of ultrafast dynamics in molecules, nanostructures, or solids with sub-cycle resolution, but previous work has so far concentrated on extracting the dielectric response at frequencies below 50 THz. Here, we implemented transient field-resolved reflectometry at 50-100 THz(3-6 mu m) with MHz repetition rate employing 800 nm few-cycle excitation pulses that provide sub-10 fs temporal resolution. The capabilities of the technique are demonstrated in studies of ultrafast photorefractive changes in semiconductors Ge and GaAs, where the high frequency range permits to explore the resonance-free Drude response. The extended frequency range in transient field-resolved spectroscopy can further enable studies with so far inaccessible transitions, including intramolecular vibrations in a large range of systems. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License

Retinal image enhancement via a multiscale morphological approach with OCCO filter.

Retinal images are widely used for diagnosis and eye disease detection. However, due to the acquisition process, retinal images often have problems such as low contrast, blurry details or artifacts. These problems may severely affect the diagnosis. Therefore, it is very impor tant to enhance the visual quality of such images. Contrast enhancement is a pre-processing applied to images to improve their visual quality. This technique betters the identification of retinal structures in degraded reti nal images. In this work, a novel algorithm based on multi-scale mathe matical morphology is presented. First, the original image is blurred us ing the Open-Close Close-Open (OCCO) filter to reduce any artifacts in the image. Next, multiple bright and dark features are extracted from the filtered image by the Top-Hat transform. Finally, the maximum bright values are added to the original image and the maximum dark values are subtracted from the original image, previously adjusted by a weight. The algorithm was tested on 397 retinal images from the public STARE database. The proposed algorithm was compared with state of the art al gorithms and results show that the proposal is more efficient in improving contrast, maintaining similarity with the original image and introducing less distortion than the other algorithms. According to ophthalmologists, the algorithm, by improving retinal images, provides greater clarity in the blood vessels of the retina and would facilitate the identification of pathologies.CONACYT - Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Pathophysiological regulation of lung function by the free fatty acid receptor FFA4.

Increased prevalence of inflammatory airway diseases including asthma and chronic obstructive pulmonary disease (COPD) together with inadequate disease control by current frontline treatments means that there is a need to define therapeutic targets for these conditions. Here, we investigate a member of the G protein-coupled receptor family, FFA4, that responds to free circulating fatty acids including dietary omega-3 fatty acids found in fish oils. We show that FFA4, although usually associated with metabolic responses linked with food intake, is expressed in the lung where it is coupled to Gq/11 signaling. Activation of FFA4 by drug-like agonists produced relaxation of murine airway smooth muscle mediated at least in part by the release of the prostaglandin E2 (PGE2) that subsequently acts on EP2 prostanoid receptors. In normal mice, activation of FFA4 resulted in a decrease in lung resistance. In acute and chronic ozone models of pollution-mediated inflammation and house dust mite and cigarette smoke-induced inflammatory disease, FFA4 agonists acted to reduce airway resistance, a response that was absent in mice lacking expression of FFA4. The expression profile of FFA4 in human lung was similar to that observed in mice, and the response to FFA4/FFA1 agonists similarly mediated human airway smooth muscle relaxation ex vivo. Our study provides evidence that pharmacological targeting of lung FFA4, and possibly combined activation of FFA4 and FFA1, has in vivo efficacy and might have therapeutic value in the treatment of bronchoconstriction associated with inflammatory airway diseases such as asthma and COPD