Foundations, Properties, and Security Applications of Puzzles: A Survey

Cryptographic algorithms have been used not only to create robust ciphertexts but also to generate cryptograms that, contrary to the classic goal of cryptography, are meant to be broken. These cryptograms, generally called puzzles, require the use of a certain amount of resources to be solved, hence introducing a cost that is often regarded as a time delay---though it could involve other metrics as well, such as bandwidth. These powerful features have made puzzles the core of many security protocols, acquiring increasing importance in the IT security landscape. The concept of a puzzle has subsequently been extended to other types of schemes that do not use cryptographic functions, such as CAPTCHAs, which are used to discriminate humans from machines. Overall, puzzles have experienced a renewed interest with the advent of Bitcoin, which uses a CPU-intensive puzzle as proof of work. In this paper, we provide a comprehensive study of the most important puzzle construction schemes available in the literature, categorizing them according to several attributes, such as resource type, verification type, and applications. We have redefined the term puzzle by collecting and integrating the scattered notions used in different works, to cover all the existing applications. Moreover, we provide an overview of the possible applications, identifying key requirements and different design approaches. Finally, we highlight the features and limitations of each approach, providing a useful guide for the future development of new puzzle schemes.Comment: This article has been accepted for publication in ACM Computing Survey

Epilepsy Classification (ILAE Classification 2017) in Resource-limited Countries: A Cross-sectional Study on Epilepsy in Pediatric Patients from Sudan

Background: The objective of this study is to utilize the ILAE 2017 to classify epilepsy patients and determine its applicability in Sudan. Methods: This study is a prospective, descriptive, cross-sectional research conducted in two pediatric epilepsy clinics in Khartoum State, Sudan. Results: In this cross-sectional study, 350 pediatric patients with epilepsy were included, with a mean age of 8.4 ± 4.7 years and a mean illness duration of 4.71 ± 3.91 years. The ILAE classification was applied, showing that 71.11% of patients had generalized onset seizures, 27.7% had focal onset seizures, and only 1.1% had unknown onset seizures. Among patients with focal onset seizures, 56.4% had intact awareness, while 43.6% had impaired levels of awareness. The majority of patients who had generalized onset seizures experienced motor onset seizures, with tonic-clonic seizures being the most common (44.2%). Nearly all patients with unknown onset seizures experienced tonic-clonic convulsions. These findings provide insights into the prevalence and types of seizures among pediatric epilepsy patients in Sudan and can guide clinicians in developing appropriate treatment plans. Conclusion: This study highlights the importance of utilizing the latest ILAE classification 2017 in epilepsy classification and its potential utilization in resource-limited areas like Sudan

Dumping Syndrome: case series of uncommon incidence following Laparoscopic Sleeve Gastrectomy (LSG)

Introduction: Dumping syndrome (DS) is a clinical impediment characterized by postprandial discomfort following bariatric-surgery. Data on incidence of DS following LSG is scarce. The purpose of this case series is to demonstrate the observation of DS in Qatari patients following Laparoscopic Sleeve Gastrectomy (LSG). Methods: Cases from the outpatients’ clinic at the department of bariatric and metabolic surgery- Hamad General Hospital, who had undergone LSG during the year 2016 were followed up for progress and data were analyzed and treatment options were discussed. Results: Five women under the age of 45 were diagnosed with DS. The first patient experienced fatigue, weakness and syncope. The second patient had a chief complaint of mild dizziness and diarrhea associated with low blood sugar. The third patient had complaints of recurrent hypoglycemia characterized by sweating, tremors, palpitations and dizziness. The fourth patient experienced significant dizziness associated with eating sweat, fatigue and low blood sugar within the first 40 minutes after meal with symptoms being relieved temporarily by sugary food. The fifth patient was presented to the emergency department with severe hypoglycemia, severe hypokalemia, fatigue, nausea, food intolerance and abdominal cramps. The majority of patients had mild-moderate symptoms with only one case presenting with severe symptoms that required hospitalization (5th patient) as blood sugar was very low (36-45 mg%) with very low potassium (2-2.5 mmol). None of the 5 patients had any comorbidity. Of the five patients, the first 4 responded to the diet modification with 2 required adding Acarbose oral tablets to control their symptoms. The fifth patient with severe symptoms had to undergo more intense therapy to control the symptoms, including administration of intravenous fluids, electrolytes correction, Acarbose, Octreotide and symptomatic treatment for abdominal pain and nausea as well as the usual diet modification and nutritional supplement. Conclusion: DS in post-LSG patients is an uncommon condition that may lead to serious deficiency complications such as hypoglycemic attacks. This is yet another example that highlights the importance of patient education prior to discharge. Patients education should focus on raising the awareness of such potential complications and healthcare providers must have the knowledge and expertise to predict and deal with such ailment. While it is strongly recommended that alternative diets are adopted to help with the recovery of afflicted patients, severe cases of DS may require medication to treat critical cases.Hamad Medical Corporatio

Determination of Antioxidant Activity of some Varieties of Onion (Allium cepa L.) grown in Sudan

Background: Medicinal plants contain physiologically active ingredients that over the years have been exploited in traditional medicine for the treatment of various ailments.  Objectives: This study was undertaken to investigate the antioxidant activity of seven varieties of onion (Allium cepa) grown in Sudan.  Methods: The antioxidant capacity was conducted based on the ability of the plant extracts to scavenge DPPH radical. Results: The extracts exhibited a notable dose dependent inhibition of DPPH radical. Shendi (Red onion local strain) exhibited the highest antioxidant activity with EC50 25.25 µg/ml followed by Kassala (Red onion local strain) and white onion with less scavenging activity was produced by Green onion. Conclusion:  It can be concluded that Allium cepa could be a potential source of antioxidant principles

Activation and contraction of human ‘vascular’ smooth muscle cells grown from circulating blood progenitors

Blood outgrowth smooth muscle cells offer the means to study vascular cells without the requirement for surgery providing opportunities for drug discovery, tissue engineering and personalised medicine. However, little is known about these cells which has meant their therapeutic potential remains unexplored. Our objective was to investigate for the first time the ability of blood outgrowth smooth muscle cells and vessel derived smooth muscle cells to sense the thromboxane mimetic U46619 by measuring intracellular calcium elevation and contraction. U46619 (10 26 -6 M) increased cytosolic calcium in blood outgrowth smooth muscle cells fibroblasts. Increased calcium signal peaked between 10-20 seconds after U46619 in both smooth muscle cell types. Importantly, U46619 (10-9 to 10-6 M) induced concentration-dependent contractions of both blood outgrowth smooth muscle cells and vascular smooth muscle cells but not in fibroblasts. In summary, we show that functional responses of blood outgrowth smooth muscle cells are in line with vascular smooth muscle cells providing critical evidence of their application in biomedical research

Recent Developments in Nanomaterials-Based Drug Delivery and Upgrading Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading causes of morbidity and mortality worldwide. However, despite the recent developments in the management of CVDs, the early and long outcomes vary considerably in patients, especially with the current challenges facing the detection and treatment of CVDs. This disparity is due to a lack of advanced diagnostic tools and targeted therapies, requiring innovative and alternative methods. Nanotechnology offers the opportunity to use nanomaterials in improving health and controlling diseases. Notably, nanotechnologies have recognized potential applicability in managing chronic diseases in the past few years, especially cancer and CVDs. Of particular interest is the use of nanoparticles as drug carriers to increase the pharmaco-efficacy and safety of conventional therapies. Different strategies have been proposed to use nanoparticles as drug carriers in CVDs; however, controversies regarding the selection of nanomaterials and nanoformulation are slowing their clinical translation. Therefore, this review focuses on nanotechnology for drug delivery and the application of nanomedicine in CVDs

Internalization of metal-organic framework nanoparticles in human vascular cells: Implications for cardiovascular disease therapy

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Alteration of endothelial cells and the underlying vasculature plays a central role in the pathogenesis of various CVDs. The application of nanoscale materials such as nanoparticles in biomedicine has opened new horizons in the treatment of CVDs. We have previously shown that the iron metal-organic framework nanoparticle, Materials Institut Lavoisier-89 (nanoMIL-89) represents a viable vehicle for future drug delivery of pulmonary arterial hypertension. In this study, we have assessed the cellular uptake of nanoMIL-89 in pulmonary artery endothelial and smooth muscle cells using microscopy imaging techniques. We also tested the cellular responses to nanoMIL-89 using molecular and cellular assays. Microscopic images showed cellular internalization of nanoMIL-89, packaging into endocytic vesicles, and passing to daughter cells during mitosis. Moreover, nanoMIL-89 showed anti-inflammatory activity without any significant cytotoxicity. Our results indicate that nanoMIL-89 formulation may offer promising therapeutic opportunities and set forth a new prototype for drug delivery not only in CVDs, but also for other diseases yet incurable, such as diabetes and cancer.- The UREP grant [22-140-3-023] from Qatar National Research Fund (QNRF), a member of Qatar Foundation. - The Pickford Award from the British Pharmacological Society (awarded to NAM). - PDRA grants [PDRA3-0324-17001 and PDRA4-0129-18003] from QNRF

Benefits from Trade Agreements for Developing vs Developed Countries. Comparative Analysis of France and Kenya

Objectives The main objectives of this study were to compare the benefits that developing and developed economies gain from the international trade agreements. In addition, the obstacles of the benefits of international trade being observed to the same extent for both developing and developed parties. Summary The research examined secondary data from databases with the aim of identifying the most relevant economic indicators about trade and how they showcase the differing rate of development and impacts in the trade structure and economy. Additionally, the main finding of this research is focused on the impacts of international trade that are derived from trade structures and agreements. Conclusions The study found that trade structures that heavily dominated by exporting primary commodities and importing manufactured goods tend to receive less benefits from international trade to their development compared to countries who do the opposite. Moreover, the overall impact of international trade has been positive on both developed and developing nations economies. Additionally, the findings suggest that the trade agreements need to include more effective terms regarding developmen

SARS-CoV-2 Papain-like Protease Responsive ZnO/Daclatasvir-Loaded Chitosan/Gelatin Nanofibers as Smart Antimicrobial Medical Textiles: In Silico, In Vitro and Cell Studies

A significant number of deaths are reported annually worldwide due to microbial and viral infections. The development of protective medical textiles for patients and healthcare professionals has attracted many researchers’ attention. Therefore, this study aims to develop smart drug-eluting nanofibrous matrices to be used as a basic material for medical textile fabrication. First, chitosan/gelatin nanofibers were selected as the basic material owing to the wide antimicrobial activity of chitosan and the capability of gelatin to be hydrolyzed in the abundance of the papain-like protease (PLpro) enzyme secreted by SARS-CoV-2. Daclatasvir (DAC), an NS5A inhibitor, was selected as the model drug based on in silico studies where it showed high anti-SARS-CoV-2 potential compared to FDA-approved references. Due to their reported antimicrobial and antiviral activities, ZnO NPs were successfully prepared and incorporated with daclatasvir in chitosan/gelatin nanofibrous matrices through electrospinning. Afterward, an in vitro release study in a simulated buffer revealed the controlled release of DAC over 21 days from the nanofibers compared to only 6 h for free DAC. On the other hand, the abundance of PLpro induced the complete release of DAC from the nanofibers in only 4–8 h. Finally, the nanofibers demonstrated a wide antimicrobial activity against S. aureus, E. coli, and C. albicans.</i