Visible Light Communication Cyber Security Vulnerabilities For Indoor And Outdoor Vehicle-To-Vehicle Communication

Light fidelity (Li-Fi), developed from the approach of Visible Light Communication (VLC), is a great replacement or complement to existing radio frequency-based (RF) networks. Li-Fi is expected to be deployed in various environments were, due to Wi-Fi congestion and health limitations, RF should not be used. Moreover, VLC can provide the future fifth generation (5G) wireless technology with higher data rates for device connectivity which will alleviate the traffic demand. 5G is playing a vital role in encouraging the modern applications. In 2023, the deployment of all the cellular networks will reach more than 5 billion users globally. As a result, the security and privacy of 5G wireless networks is an essential problem as those modern applications are in people\u27s life everywhere. VLC security is as one of the core physical-layer security (PLS) solutions for 5G networks. Due to the fact that light does not penetrate through solid objects or walls, VLC naturally has higher security and privacy for indoor wireless networks compared to RF networks. However, the broadcasting nature of VLC caused concerns, e.g., eavesdropping, have created serious attention as it is a crucial step to validate the success of VLC in wild. The aim of this thesis is to properly address the security issues of VLC and further enhance the VLC nature security. We analyzed the secrecy performance of a VLC model by studying the characteristics of the transmitter, receiver and the visible light channel. Moreover, we mitigated the security threats in the VLC model for the legitimate user, by 1) implementing more access points (APs) in a multiuser VLC network that are cooperated, 2) reducing the semi-angle of LED to help improve the directivity and secrecy and, 3) using the protected zone strategy around the AP where eavesdroppers are restricted. According to the model\u27s parameters, the results showed that the secrecy performance in the proposed indoor VLC model and the vehicle-to-vehicle (V2V) VLC outdoor model using a combination of multiple PLS techniques as beamforming, secure communication zones, and friendly jamming is enhanced. The proposed model security performance was measured with respect to the signal to noise ratio (SNR), received optical power, and bit error rate (BER) Matlab simulation results

Enhanced Optical Wireless Channel For Indoor And Intravehicle Communications: Power Distribution And Signal To Noise Ratio Analysis

Visible light communication—(VLC) provides wide bandwidth and high security capabilities for free space optical communication. This thesis presents the key concepts, underlying principles and practical applications of visible light communications. In particular, this thesis focuses on the received power distribution pattern and signal to noise ratio for line-of-sight indoor and vehicular applications. Several methods are used to modify the SNR and power distribution levels. It is shown that in the absence of obstruction, the optical footprint is nearly circular and offers a platform for large- scale deployment in commercial environments, which is similar to micro and Pico cells. By studying various kinds of commonly used VLC channel analysis: diffuse and line of sight channels, a simple improved indoor and intra-vehicular VLC transmission model for power distribution and SNR is presented. Employing optical wireless communications within the vehicle not only enhances user mobility, but also alleviates radio frequency interference, and lowers system cost through the utilization of license free spectrum. Moreover, a solution to increase the received power by changing the semi angle at half power is presented. The simulation results show the improved received power distribution and SNR. A VLC system, based on color-shift-keying (CSK) modulation and code-division multiple-access (CDMA) is presented. CSK–CDMA VLC system is used to enhance the VLC system capacity and mitigate single color light interference, which allows multiple users to access the network

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Soluble and membranous endothelial protein C receptor in systemic lupus erythematosus patients: Relation to nephritis

Aim of the work: To investigate the role of endothelial protein C receptor (EPCR) (membrane and soluble forms) as a biomarker of lupus nephritis (LN) in systemic lupus erythematosus (SLE) patients and to study its relation to the prognosis and response to treatment. Patients and methods: The study included 30 SLE patients and 30 matched healthy volunteers as well as 10 renal biopsies from surgical nephrectomy as a control for membranous (mEPCR) examination. SLE disease activity index-2000 and damage index were assessed. Serum sEPCR was measured. Renal expression of mEPCR was analyzed. All patients were reassessed after 3 months. Results: Patients were 26 females and 4 males with a mean age of 29.6 ± 10.04 years and disease duration of 4.4 ± 3.5 years. Their mean SLEDAI was 13.9 ± 9.9 and damage index 1 ± 1.5. Serum levels of sEPCR were significantly higher in patients with LN (19.9 ± 5.7 ng/ml) than those without (8.95 ± 4.2 ng/ml) and controls (5.3 ± 2.6 ng/ml)(p < 0.001). SLE patients with cutaneous vasculitis (n = 9) had significantly higher sEPCR levels than those without (18.1 ± 7.8 vs 10.2 ± 5.2 ng/ml)(p = 0.02). There was a significant correlation between sEPCR percentage of change and of SLEDAI-2k with and without LN (p < 0.01 and p < 0.05). A significant difference was observed in sEPCR according to the prognosis and treatment response after 3 months. mEPCR stained positively in glomeruli and tubules of LN patients with no relation to histopathological grading. Conclusion: sEPCR plays a role in the pathogenesis, is related to a bad prognosis and poor response to treatment in LN. mEPCR was not related to LN grading. Keywords: Lupus nephritis, Systemic lupus erythematosus, Soluble and membranous EPCR, ELIS, AImmunohistochemistr

Evaluation of endothelial protein C receptor in patients with systemic lupus erythematosus: correlation with disease activity and lupus nephritis

Introduction Systemic lupus erythematous (SLE) is a systemic, multifaceted inflammatory disease with clinical manifestations is protean and follows a relapsing and remitting course. Lupus Nephritis (LN) is one of the most frequent and serious manifestation. Endothelial protein C receptor (EPCR) is a transmembrane receptor that is shed into soluble form (sEPCR) in inflammatory status. It is demonstrated as a part of the pathobiology of the SLE disease. Aim of the work To assess correlation of sEPCR level in SLE patients to the disease activity in these patients and to relate sEPCR to LN. Patients and methods Serum level of sEPCR using enzyme-linked immunosorbent assay (ELISA), chemical and immunological markers of SLE were measured in 30 SLE patients and 30 age and sex matched apparently healthy controls. SLE patients were subgrouped into 20 patients without LN and 10 with LN. Disease activity was assessed using SLE Disease Activity Index (SLEDAI). Results A significantly higher sEPCR level was found on comparing SLE patients to controls with statistically highly significant difference (z = 4.8, P < 0.001). Moreover, there was a significantly higher sEPCR level on comparing SLE patients with LN to those without LN with statistically highly significant difference (z = 3.9, P < 0.001). Serum sEPCR had a highly significant positive correlation with SLEDAI in SLE patients (r = 0.66, P < 0.01). Conclusion sEPCR has a possible role in the pathogenesis of SLE and particularly LN diseases, reflecting disease activity in SLE patients

Proline synthesis through PYCR1 is required to support cancer cell proliferation and survival in oxygen-limiting conditions

The demands of cancer cell proliferation alongside an inadequate angiogenic response lead to insufficient oxygen availability in the tumor microenvironment. Within the mitochondria, oxygen is the major electron acceptor for NADH, with the result that the reducing potential produced through tricarboxylic acid (TCA) cycle activity and mitochondrial respiration are functionally linked. As the oxidizing activity of the TCA cycle is required for efficient synthesis of anabolic precursors, tumoral hypoxia could lead to a cessation of proliferation without another means of correcting the redox imbalance. We show that in hypoxic conditions, mitochondrial pyrroline 5-carboxylate reductase 1 (PYCR1) activity is increased, oxidizing NADH with the synthesis of proline as a by-product. We further show that PYCR1 activity is required for the successful maintenance of hypoxic regions by permitting continued TCA cycle activity, and that its loss leads to significantly increased hypoxia in&#xA0;vivo and in 3D culture, resulting in widespread cell death

Proline synthesis through PYCR1 is required to support cancer cell proliferation and survival in oxygen-limiting conditions

The demands of cancer cell proliferation alongside an inadequate angiogenic response lead to insufficient oxygen availability in the tumor microenvironment. Within the mitochondria, oxygen is the major electron acceptor for NADH, with the result that the reducing potential produced through tricarboxylic acid (TCA) cycle activity and mitochondrial respiration are functionally linked. As the oxidizing activity of the TCA cycle is required for efficient synthesis of anabolic precursors, tumoral hypoxia could lead to a cessation of proliferation without another means of correcting the redox imbalance. We show that in hypoxic conditions, mitochondrial pyrroline 5-carboxylate reductase 1 (PYCR1) activity is increased, oxidizing NADH with the synthesis of proline as a by-product. We further show that PYCR1 activity is required for the successful maintenance of hypoxic regions by permitting continued TCA cycle activity, and that its loss leads to significantly increased hypoxia in vivo and in 3D culture, resulting in widespread cell death