Optical control plane: theory and algorithms

In this thesis we propose a novel way to achieve global network information dissemination in which some wavelengths are reserved exclusively for global control information exchange. We study the routing and wavelength assignment problem for the special communication pattern of non-blocking all-to-all broadcast in WDM optical networks. We provide efficient solutions to reduce the number of wavelengths needed for non-blocking all-to-all broadcast, in the absence of wavelength converters, for network information dissemination. We adopt an approach in which we consider all nodes to be tap-and-continue capable thus studying lighttrees rather than lightpaths. To the best of our knowledge, this thesis is the first to consider “tap-and-continue” capable nodes in the context of conflict-free all-to-all broadcast. The problem of all to-all broadcast using individual lightpaths has been proven to be an NP-complete problem [6]. We provide optimal RWA solutions for conflict-free all-to-all broadcast for some particular cases of regular topologies, namely the ring, the torus and the hypercube. We make an important contribution on hypercube decomposition into edge-disjoint structures. We also present near-optimal polynomial-time solutions for the general case of arbitrary topologies. Furthermore, we apply for the first time the “cactus” representation of all minimum edge-cuts of graphs with arbitrary topologies to the problem of all-to-all broadcast in optical networks. Using this representation recursively we obtain near-optimal results for the number of wavelengths needed by the non-blocking all-to-all broadcast. The second part of this thesis focuses on the more practical case of multi-hop RWA for non- blocking all-to-all broadcast in the presence of Optical-Electrical-Optical conversion. We propose two simple but efficient multi-hop RWA models. In addition to reducing the number of wavelengths we also concentrate on reducing the number of optical receivers, another important optical resource. We analyze these models on the ring and the hypercube, as special cases of regular topologies. Lastly, we develop a good upper-bound on the number of wavelengths in the case of non-blocking multi-hop all-to-all broadcast on networks with arbitrary topologies and offer a heuristic algorithm to achieve it. We propose a novel network partitioning method based on “virtual perfect matching” for use in the RWA heuristic algorithm

Photolysis of Bovine Serum Albumin by near UV irradiation

Proteins are major biological targets for oxidative damage due to their abundance and high rates of reactions with reactive oxygen species including radicals and excited state species. This work studies the photooxidation of Bovine Serum Albumin (BSA) by singlet molecular oxygen (1O2) using Raman spectroscopy which allows the spectral changes induced by oxidation to be directly identified. The results show that these changes mainly affect the S-S and the amide Raman bands. Tri-peptides containing amino acids His, Met, Trp and Tyr whose side chains are known to preferentially react with 1O2 are also analysed allowing the specific changes associated with each amino acid to be observed and discussed within the context of the changes observed in the protein. The singlet oxygen quenching rate constants for BSA were measured using time resolved near infrared phosphorescence. It was found that the rate constants vary as a function of pD thus highlighting the effect of conformation on the process of oxidation

Cardio metabolic risk factors for atrial fibrillation in type 2 diabetes mellitus: Focus on hypertension, metabolic syndrome and obesity

Objective. Atrial fibrillation (AF) in type 2 diabetes mellitus (T2DM) has been little explored so far. However, there are several cardio metabolic risk factors for AF in T2DM patients, such as arterial hypertension, obesity or the metabolic syndrome. Our objective was to evaluate cardio metabolic risk factors for AF in T2DM patients. Methods. We studied the medical records of T2DM patients hospitalized in the Internal Medicine department of an emergency referral hospital in Bucharest, Romania. The study was observational, retrospective and carried out between January-June 2018. Results. The study group included 221 T2DM patients (with a mean age of 68.65 ± 10.64, ranging between 37-93 years): 116 women (52.49%; with a mean age of 70.53 ± 10.69, ranging between 37-93 years) and 105 men (47.51%; with a mean age of 66.57 ± 10.23, ranging between 38-91 years). 92 patients had AF (41.63%): 40 women (34.48%) and 52 men (49.52%). 180 patients (81.45%) were hypertensive: 103 women (88.79%) and 77 men (73.33%). 113 patients (51.13%) had metabolic syndrome: 58 women (50.00%) and 55 men (52.38%). 77 patients (34.84%) were obese: 45 women (38.79%) and 32 men (30.48%). AF patients associated obesity in 26 cases (28.26%), hypertension in 73 cases (79.35%) and metabolic syndrome in 56 cases (60.87%). Conclusions. Out of the study group, 92 T2DM patients (41.63%) had AF, men being more likely to suffer from AF than women (p=0.0288). Hypertension affected 180 patients (81.45%) and in greater proportion women vs. men (p=0.0051). The metabolic syndrome and obesity were discovered in 113 patients (51.13%) and 77 patients (34.84%), respectively, with no significant differences in terms of gender. In our research, the highest cardio metabolic risk factors for AF in T2DM were hypertension (OR = 3.6675) and the metabolic syndrome (OR = 3.3388)

Cardiovascular Risk Factors in Patients with Chronic Plaque Psoriasis: A Case-control Study on the Brasov County Population

Many studies have suggested that cardiovascular risk factors seem to be more common in patients with psoriasis than in the general population. In this study we aimed to determine the prevalence of cardiovascular risk factors in patients with chronic plaque psoriasis depending on the severity of disease. We conducted a prospective study in Braşov County (Romania) including 142 patients with chronic plaque psoriasis and disease duration of at least six months and 167 controls without psoriasis. The severity of psoriasis was assessed using the psoriasis area and severity index (PASI) score. Along with a thorough medical history and physical examination, serum lipid profile and fasting plasma glucose tests were carried out. The 10-year Framingham risk score (FRS) for general cardiovascular disease, which includes age, gender, total cholesterol, HDL-cholesterol, systolic blood pressure, smoking status, and diabetes mellitus, was applied.  The severity of chronic plaque psoriasis was mild in 32 patients (22.53%) and moderate to severe in 110 patients (77.47%). We found a significant higher prevalence of metabolic syndrome in the patient group compared to controls. Individual components of metabolic syndrome like waist circumference, elevated triglycerides, reduced HDL-C, impaired fasting plasma glucose, and arterial hypertension were also more prevalent in patients than in controls. Mean triglycerides, total cholesterol, LDL-cholesterol and HDL-cholesterol levels were significantly raised in patients with psoriasis when compared to controls. The 10-year FRS was significantly higher in patients with psoriasis than in controls (8.36±5.75 vs. 6.61±4.13; P&lt;0.001). FRS was higher in men (P=0.012) and in patients older than 50 years (P=0.008). According to the severity of psoriasis, FRS increases significantly from mild to moderate-to-severe psoriasis (6.82±4.48 to 8.8±6.71; P=0.003). Psoriasis, and especially moderate to severe psoriasis, seems to represent a risk factor for cardiovascular disease. Patients with psoriasis should be risk-assessed for cardiovascular diseases, and comorbidities should be actively managed.</p

Comparative study of Ti and Ti alloy for possible medical application

In the realm of modern medicine, the quest for innovation and improvement is relentless. One significant development that has transformed the landscape of medical devices and implants is the use of titanium and titanium alloys. Just as Titan stands as a resilient moon in the outer reaches of our cosmic neighborhood, titanium and its alloys have emerged as robust and versatile materials for a wide array of medical applications. From orthopedic implants to dental prosthetics, and even in cutting-edge biomedical engineering, titanium's exceptional combination of strength, biocompatibility, and corrosion resistance has made it an indispensable asset in modern medicine. Titanium and its alloys are not just elements on the periodic table; they are key elements in the quest for stronger, longer-lasting, and more effective medical treatments and devices

Preliminary studies of new Ti alloys with different Mo content

This work aims to investigate the mechanical characteristics and biocompatibility of two novel titanium alloys, Ti15Mo7Zr15Ta1Si and Ti20Mo7Zr15Ta0,75Si.These samples have previously undergone cutting, grinding, polishing, and chipping. The studied samples were subjected to electrochemical, metallographic and corrosion behavior. Ti15Mo7Zr15Ta1Si and Ti20Mo7Zr15Ta0.75Si, the study samples, have demonstrated high corrosion potentials, lower corrosion rates, and consequently higher corrosion resistance. In summary, this study's data indicates that both alloys exhibit good corrosion behavior