Electrical Size Reduction of Microstrip Antennas by Using Defected Ground Structures Composed of Complementary Split Ring Resonator

In this study the effects of using defected ground structures (DGS) composed of a complementary split ring resonator (CSRR) and CSRR with dumbbell (CSRR-D) for rectangular microstrip antennas are investigated. On this aim, two different antennas, which are Antenna B having CSRR etched DGS and Antenna C having CSRR-D etched DGS are designed and fabricated in comparison with the ordinary rectangular patch antenna, which is Antenna A. In both Antenna B and C, CSRR structures are etched in the same position of the ground planes. On the other hand, another ordinary microstrip antenna, called Antenna D, is designed at resonance frequency of Antenna C. For the characterization, resonance frequencies, voltage standing wave ratios, percentage bandwidths, gains, ka values and gain radiation patterns are investigated both in simulations and experiments. The numerical analyses show that 29.39 % and 44.49 % electrical size reduction (ESR) ratios are obtained for Antenna B and Antenna C, respectively in comparison to Antenna A. The experimental results verify the ESR ratios with 29.15 % and 44.94 %. Supporting, Antenna C promises 68.12 % physical size reduction (PSR) as it is compared with Antenna D. These results reveal that Antenna C is a good alternative for DGS based microstrip electrically small antennas

Effect of guar gum on the physicochemical, thermal, rheological and textural properties of green edam cheese

In attempts to produce a low-fat cheese with a rheology and texture similar to that of a full-fat cheese, guar gum (within 0.0025–0.01%; w/v, final concentration) was added to low-fat milk. The obtained cheeses were characterised regarding their physicochemical, thermal, rheological and textural properties. Control cheeses were also produced with low and full-fat milk. The physicochemical properties of the guar gum modified cheeses were similar to those of the low-fat control. No significant differences were detected in the thermal properties (concerning the enthalpy and profile of water desorption) among all types of cheeses. The rheological behaviour of the 0.0025% modified cheese was very similar to the full-fat control. Overall, no trend was observed in the texture profile (hardness, cohesiveness, gumminess and elasticity) of the modified cheeses versus guar gum concentration, as well as in comparison with the control groups, suggesting that none of the studied polysaccharide concentrations simulated the textural functions of fat in Edam cheese

Association between standardized uptake value and survival in patients with locally advanced or metastatic squamous cell head and neck cancer

Introduction and objective: The present study aimed to evaluate the association between tumor Standard Uptake Value (SUVmax) values obtained by PET/CT, and survival in patients with locally advanced or metastatic squamous cell head and neck cancer. Method: The present study included 38 patients with locally advanced or metastatic squamous cell head and neck cancer, who were staged using PET/CT at diagnosis. PET/CT imaging findings were evaluated retrospectively. The effect of SUVmax value by PET/CT on overall survival was analyzed. Results: The most common tumor localization was laryngeal cancer among 38 patients included in the study (n = 25, 65.8%). The study group consisted of mostly male patients (n = 33, 86.8%), and the median age was 58 (range: 24–77). The median SUVmax value was 11 (range: 3–58). Median survival was 32.7 months in patients with SUVmax ≤11 compared to 16.5 months in patients with SUVmax >11 (p = 0.019)

Effects of educational status and the living environment on the prognosis of head and neck squamous cell carcinoma

Introduction and purpose: Educational status and the living environment are closely related to the survival rates of patients with head and neck cancer. In this study we evaluate the effects of educational status and the living environment on the survival of patients with head and neck cancer. Materials and methods: Patients with head and neck tumors that show squamous cell histological properties were included in the study. Cases had been followed up in Dicle University Medical Faculty Medical Oncology clinic between January 2006 and June 2013. Data was collected retrospectively from the medical records of the patients. Classical parameters, which are considered to affect the prognosis, such as age, gender, stage, tumor localization and performance status, were investigated, in addition to educational status and the living environment. Results: The study comprised 171 cases. The rate of metastatic disease was determined to be higher in illiterate patients, when compared to ones with at least an elementary school or higher education (12.7% and 8.1%, respectively; p = 0.012). Similarly, patients living in rural areas showed higher rates of metastatic disease, when compared to those living in cities (16.3% and 8.0%, respectively; p = 0.146). It was determined that the educational status (median overall survival in the cases with elementary school or higher education 21.5 months; in cases that cannot read or write, it is 10.3 months; p = 0.001) and the environment being lived (median overall survival in cases living in cities 17.6 months; in cases living in rural areas it is 9.0 months; p = 0.014) affect survival in the patients with head and neck cancer. In the multivariate analysis; age (>60 vs < 60, OR: 1.94, 95% CI 1.19–3.17, p = 0.008), educational status (cases that cannot read or write vs elementary school or higher, OR: 1.64, 95% CI: 1.03–2.62, p = 0.037) and stage (early stage vs local advanced stage, OR: 3.07, 95% CI: 1.58–5.94, p = 0.01, early stage vs late stage, OR: 3.49, 95% CI: 1.52–8.03, p = 0.003) were determined to be independent prognostic factors. Discussion: In addition to the classical prognostic factors, educational status was also determined to be an independent prognostic factor in the squamous cell head and neck cancers, and this fact was especially related with late diagnosis. The prognostic effect of living in rural area was determined by univariate analysis; however it was not determined to be an independent prognostic factor in the multivariate analysis

Alopecia neoplastica as a sign of visceral malignancies: a systematic review

Alopecia neoplastica (AN) from visceral tumours is a rare form of cutaneous metastasis in which internal malignancies spread to the scalp. The diagnosis of AN may be very challenging, especially when its onset precedes the diagnosis of the primary tumour. We aimed to improve the knowledge on AN, highlighting that in case of scarring localized alopecia, a differential diagnosis with metastasis should always be considered. We performed a systematic review to describe the main demographic and clinical features associated with AN from visceral malignancies; a survival analysis was also performed. In 118 reports, accounting for 123 patients, we found that women were more affected by AN than men (53.7% vs. 46.3%). The most frequent site of the primary tumour was the gastrointestinal tract (24.4%), followed by breast (17.9%), kidney (8.1%), lung (7.3%), thyroid (7.3%), uterus (6.5%), central nervous system (6.5%), liver (3.3%) and other anatomic areas for 18.7% of cases. Furthermore, in more than half of the cases (66.1%), AN lesions were single and were mainly diagnosed after the primary visceral tumour (71.5%). Finally, survival analysis highlighted a lower progression-free survival in men; while, no significant differences in overall survival were reported among genders. In conclusion, metastatic skin disease should always be taken into consideration when dealing with patients with localized scarring alopecia