New Design of Channel Drop Filter by Triangular Photonic Crystal

We have designed a new type of optical channel drop filter (CDF) based on two dimensional triangular lattice photonic crystals. CDF operation is based on coupling to the photonic crystal waveguide. The proposed structure is optimized to work as a CDF. For obtaining the CDF characteristics and band structure of the filter, the finite difference time domain (FDTD) method and plane wave expansion (PWE) method are used respectively. Dropping efficiency at 1556nm and quality factor (Q) of our proposed structure are 100% and 260, respectively. The quantities of quality factor and transmission efficiency are suitable for optical applications. The overall size of the proposed add drop filter is 191.97µm2, which is smaller than the filters already reported and it is highly desirable for photonic integrated circuits (PICs).DOI:http://dx.doi.org/10.11591/ijece.v3i1.193

Obecność przeciwciał przeciw Chlamydia pneumoniae wśród irańskich chorych na stwardnienie rozsiane: badanie pilotażowe

Background and purpose Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system. Genetic and environmental factors could not completely explain the pathogenesis of the disease. Among environmental factors, infectious agents are of more interest than other candidates, so Chlamydia pneumoniae (C. pneumoniae) may have a role in MS development or progression. This study aimed to evaluate C. pneumoniae seropositivity in MS patients. Material and methods Serum samples obtained from a cohort of 85 patients with MS and from 50 age- and sex-matched controls were assessed for the presence of antibodies. IgM and IgG concentration for C. pneumoniae were determined with enzyme-linked immunosorbent assay (ELISA). Results The mean age was 33.8 (9.96) years in the MS group and 33.9 (10.7) years in controls. Female/male ratio was 3.5 : 1 in the MS group; 69 patients (81%) had relapsing-remitting course (RRMS) and 16 patients (19%) had secondary progressive course (SPMS). The median concentration of C. pneumoniae IgM in the MS group was 0.5 RU/mL (0.25–1) versus 0.5 RU/mL (0.3–0.8) in the control group (p = 0.66); likewise, the median concentration of C. pneumoniae IgG in MS patients was 57.3 RU/mL (17.05–95.1) compared with 56.15 RU/mL (6.85–102.5) in the control group (p = 0.85). Regarding the clinical course, C. pneumoniae IgG was 55.1 RU/mL (20.7–88.6) in RRMS and 59.1 RU/mL (5.35–112) in SPMS (p = 0.8). Conclusion No association was observed between MS and C. pneumoniae in Iranian MS patients.Wstęp i cel pracy Stwardnienie rozsiane (SR) jest przewlekłą zapalną chorobą autoimmunologiczną ośrodkowego układu nerwowego. Czynniki genetyczne i środowiskowe nie tłumaczą w pełni patogenezy choroby. Wśród czynników środowiskowych szczególne zainteresowanie budzą drobnoustroje powodujące zakażenia. Chlamydia pneumoniae (C. pneumoniae) mogłaby odgrywać rolę w powstawaniu lub postępie SR. Celem badania była ocena obecności przeciwciał przeciwko C. pneumoniae w surowicy chorych na SR. Materiał i metody Od 85 chorych na SR i od 50 osób z grupy kontrolnej, dobranych pod względem wieku i płci, pobrano krew i za pomocą testów immunoenzymatycznych (ELISA) zbadano stężenia IgM i IgG przeciwko C. pneumoniae w surowicy. Wyniki Średnia wieku wyniosła 33,8 (9,96) roku w grupie chorych na SR i 33,9 (10,7) roku w grupie kontrolnej. W grupie chorych na SR proporcja kobiet do mężczyzn wyniosła 3,5 : 1. U 69 pacjentów (81%) choroba miała przebieg nawracająco-zwalniający, a u 16 pacjentów (19%) – wtórnie postępujący. Mediana stężenia IgM przeciwko C. pneumoniae wyniosła 0,5 RU/ml (0,25–1) w grupie chorych na SR w porównaniu z 0,5 RU/ml (0,3–0,8) w grupie kontrolnej (p = 0,66). Mediana stężenia IgG przeciwko C. pneumoniae wyniosła 57,3 RU/ml (17,05–95,1) w grupie chorych na SR w porównaniu z 56,15 RU/ml (6,85–102,5) w grupie kontrolnej (p = 0,85). Mediana stężenia IgG przeciwko C. pneumoniae wśród chorych na nawracająco-zwalniające SR wyniosła 55,1 RU/ml (20,7–88,6), a w grupie chorych z postacią wtórnie postępującą choroby − 59,1 RU/ml (5,35–112) (p = 0,8). Wnioski Wśród irańskich chorych na SR nie stwierdzono związku między SR a występowaniem przeciwciał przeciwko C. pneumoniae

Analysis and Improvement of the securing RFID systems conforming to EPC Class 1 Generation 2 standard

Radio Frequency IDentification (RFID) technology is a wireless identification method in which security and privacy are important parameters for public acceptance and widespread use. In order to thwart such security and privacy problems, a wide variety of authentication protocols have been proposed in the literature. In 2010, Yeh et al’s proposed a new RFID authentication protocol conforming to EPC Class 1 Generation 2 standard. They claimed that this protocol is secure against DoS attack, replay attack, DATA forgery attack, and provides untraceability and forward secrecy. In 2012, Yoon showed that this protocol does not provide forward secrecy and DATA integrity. He improved the protocol and tried to eliminate the weaknesses and claimd that the improved protocol does not have the weaknesses of the primary protocol. In this paper, we show that the improved protocol has some weaknesses including DoS attack, back-end server impersonation, tag impersonation and DATA forgery attack. We also show that it can not provide forward secrecy of the reader and untraceability. We improve the protocol, which offers a high level of security and provides mutual authentication, untraceability and forward secrecy as well as resistance to DATA forgery, replay and DoS attacks, while retaining a competitive communication cost

Muscle strength in diabetics compared to non-diabetic elderly subjects: A cross sectional and case-control study

Background: With the growing population of the elderly, the prevalence of disabilities and chronic diseases will also likely increase. Muscle weakness leads to low amounts of physical activity in elderly diabetic patients and makes them susceptible to falls. In this study, we aimed to compare the muscle strength between diabetic and non-diabetic elderly individuals. Methods: The present study is part of the the Amirkola Health and Ageing Project (AHAP) cohort performed on 1320 elderly individuals. Diabetic and non-diabetic subjects were considered as case and control groups, respectively. A diagnosis of diabetes was assigned to patients who were previously diagnosed and those with repeated fasting blood sugar FBS≥126mg/dl. Digi Hand Dynamometer device and manual muscle testing (MMT) grading systems were used to assess muscle force in the upper and lower extremities, respectively. Data were then analyzed and p<0.05 was considered significant. Results: 29.8 of the total participants (n=393) were diabetics. In the case group, 143 (36.4 of all diabetics) had weak upper extremity muscles. The number was 314 (33.9) among non-diabetics (P=0.38). We saw decreased lower extremity muscle force in 134 (34.1) diabetic individuals and 292 (31.5) non-diabetics (P=0.35). Statistical analysis showed no significant difference in any of the lower or upper extremity muscle forces between diabetics and non-diabetics (p>0.05). Conclusion: Our findings indicate that diabetes mellitus (DM) affects neither the upper nor the lower extremity muscle force in the elderly

Evaluation of Vitamin D3 and D2 Stability in Fortified Flat Bread Samples During Dough Fermentation, Baking and Storage

Purpose: Vitamin D, a fat-soluble secosteroid, has a significant role in bone metabolism and helps calcium absorption in the body. Since vitamin D concentration is altered in fortified foods and dietary supplements, the actual amount of vitamin D may differ from the label value. Methods: In this study, the concentrations of vitamin D2 and D3 of fortified bread sample were analytically determined. For this purpose, dough or homogenized bread sample was saponified using potassium hydroxide solution (30%, w/v) at 80°C, and the saponified analytes were extracted into n-heptane followed by liquid-liquid extraction. Then n-heptane fraction was evaporated to dryness and the sample was reconstituted in methanol. The effect of different parameters was evaluated by one variable at one-time strategy. Results: The analytes concentrations were evaluated in dough fermentation, baking and storage steps. The effect of temperature in dough fermentation and baking was evaluated at the range of 5-30 and 200-250°C, respectively. Also, the fermentation time was studied in the range of 0-120 min. The analytes concentrations were followed for 1 to 5 days after baking. The results indicated that dough fermentation temperature has no significant effect on the concentration of the analytes. On the other hand, when the dough fermentation time and baking temperature are increased, the analytes concentrations are decreased. Also, the storage duration of the spiked bread samples decreased the analytes concentrations after one day. Conclusion: Based on the obtained results, baking the dough at high temperatures lead to decrease in vitamin levels

A study on organogenesis in Lycopersicon esculentum Mill.

Tomato (Lycopersicum esculentum Mill.) is one of the most important horticultural crops, belonging to the family Solanaceae. Owing to the significance of tomato as a model plant in genetic studies, little is known about the floral development in this plant. The organogenesis of tomato flowers was studied using epi-illumination light microscopy. The flowers were pentamerous with the acropetal and asynchronous inception of floral whorls. The initiation of sepals, petals and stamens followed helically, unidirectionally and bidirectionally, respectively. The high occurrence of floral abnormalities was remarkable. The initiation of a higher number of organ primordia was observed for sepals, petals, stamens and carpels. The increase in the number of organs resulted from the duplication of organ primordia, especially for the stamen whorl. Based on previous studies, low temperature was probably responsible for the abnormal development of tomato flowers