A new optimized bowl-shaped mono-core surface plasmon resonance based cancer sensor is proposed for the rapid detection of different types of cancer affected cell. By considering the refractive index of each individual cancer contaminated cell with respect to their normal cell, some major optical parameters variation are observed. Moreover, the cancerous cell concentration is considered at 80% in liquid form and the detection method is finite element method with 2 100 390 mesh elements. The variation of spectrum shift is obtained by plasmonic band gap between the silica and cancer cell part which is separated by a thin (35 nm) titanium film coating. The proposed sensor depicts a high birefringence of 0.04 with a maximum coupling length of 66 μm. However, the proposed structure provides an optimum wavelength sensitivity level between about 10 000 nm/RIU and 17 500 with a resolution of the sensor between 1.5 × 10 −2 and 9.33 × 10 −3 RIU. Also, the transmittance variance of the cancerous cell ranges from almost 3300 to 6100 dB/RIU and the amplitude sensitivity ranges nearly between −340 and −420 RIU −1 for different cancer cells in major polarization mode with the maximum detection limit of 0.025. Besides, the overall sensitivity performance is measured with respect to their normal cells which can be better than any other prior structures that have already proposed.

In this paper, a highly sensitive gas sensor based on the microstructure core and cladding photonic crystal fiber (PCF) is presented over the wavelength range from 1.3 to 2.2 μm, which is advantageous for sensor fabrication. The guiding properties of the proposed structure are dependent on geometrical parameters and wavelengths, which are numerically investigated by using a finite element method (FEM). Introducing the microstructure core makes it possible to obtain higher relative sensitivity and achieves low confinement loss. Moreover, it can be shown that increasing the diameter of the air holes in the microstructure core and decreasing the size of hole to hole space (pitch), the relative sensitivity is enhanced. In addition, the confinement loss is reduced by increasing the value of the diameter of the air holes in the cladding. Simulation results reveal that for the optimum design of the proposed PCF it is possible to obtain the highest relative sensitivity of about 42.27% at the wavelength λ=1.33  μm for the absorption line of methane (CH₄) and hydrogen fluoride (HF) gases. In this case, the confinement loss of the fiber is 4.78345×10^-6 dB/m.

ObjectivesThe aims of the research are to examine the problems of abnormal menopausal women: the relationship between depression and menopausal-specific quality of life (MENQOL)-symptoms among postmenopausal women; the association of MENQOL-symptoms between pre- and postmenopausal female society in Bangladeshi real community.MethodsThis cross sectional study was conducted on 435 women of Tangail, aged (≥ 17) years, using a structured questionnaire where is inaacluded the information of MENQOL and one of the main outcomes “depression” is measured by beck depression inventory.ResultsMenopausal status and MENQOL symptoms (except pain) are significantly (P < 0.05) associated. By using post-hoc analysis, the proportion of menopausal women, classified as having a depressive mood of early menopause is significantly higher than natural-menopause. Among postmenopausal women, there is a significant correlation between “concentration problem” and “depression”. Here mean depression score (29.40 ± 6.42) of menopausal women who have any difficulty in concentrating is higher than mean depression score (20.89 ± 6.64) of menopausal women who have no difficulty in concentrating. Another six factors (osteoporosis, heart-beating, fatigue, pressure, tingling, headaches) of MENQOL-symptoms were significantly correlated with depression and P-values are 0.000, 0.000, 0.000, 0.033, 0.006, and 0.002, respectively. Finally the presence of “difficulty in concentrating” and “fatigue” are strongly associated factors with depression score (P < 0.001).ConclusionsThe early postmenopausal women have to face more psychological problems (e.g., depression) compare to others. Among postmenopausal women, there is no significant relation between depression and vasomotor symptom (e.g., hot-flashes) perspective to menopausal female society of Bangladesh.

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Provisioning of quality of service (QoS) is a key issue in visible light communication (VLC) system as well as in other wireless communication systems. Due to the fact that QoS requirements are not as strict for all traffic types, more calls of higher priority traffic classes can be accommodated by blocking some more calls of lower priority traffic classes. Diverse types of high data rate traffic are supported by existing wireless communication systems while the resource is limited. Hence, priority based resource allocation can ensure the service quality for the calls of important traffic class. The fixed guard channels to prioritize any class of calls always reduce the channel utilization. In this paper we propose a priority based dynamic channel reservation scheme for higher priority calls that does not reduce the channel utilization significantly. The number of reserved channels for each of the individual traffic classes is calculated using real-time observation of the call arrival rates of all the traffic classes. The features of the scheme allow reduction of the call blocking probability of higher priority calls along with the increase of the channel utilization.The proposed Markov Chain model is expected to be very much effective for the queuing analysis especially for the priority scheme of any number of traffic classes. The numerical results show that the proposed scheme is able to attain reasonable call blocking probability of higher priority calls without sacrificing channel utilization.

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A photonic crystal fiber in square lattice architecture is numerically investigated and proposed for broadband dispersion compensation in optical transmission system. Simulation results reveal that it is possible to obtain an ultra-high negative dispersion of about −571.7 to −1889.7 (ps/nm.km) in the wavelength range of 1340 nm to 1640 nm. Experimentally it is demonstrated that the design fiber covers a high birefringence of order 4.74×10‒3 at the wavelength of 1550 nm. Here, numerical investigation of guiding properties and geometrical properties of the proposed PCF are conducted using the finite element method (FEM) with perfectly match layers. Moreover, it is established more firmly that the proposed fiber successfully compensates the chromatic dispersion of standard single mode in entire band of interest. Our result is attractive due to successfully achieve ultra-high negative dispersion that is more promisor than the prior best results.