RESUMO
The enhancement of optical characteristics at optical frequencies deviates with the choice of the arrangement of core-shell nanoparticles and their environment. Likewise, the arrangements of core-shell nanoparticles in the air over a substrate or in liquid solution makes them unstable in the atmosphere. This article suggests designing a configuration of an active spherical coated nanoparticle antenna and its extended array in the presence of a passive dielectric, which is proposed to be extendable to construct larger arrays. The issue of instability in the core-shell nanoantenna array models is solved here by inserting the passive dielectric. In addition to this, the inclusion of a dielectric in the array model reports a different directivity behaviour than the conventional array models. We found at first that the combination model of the active coated nanoparticle and passive sphere at the resonant frequency can excite a stronger field with a rotated polarization direction and a propagation direction different from the incident plane-wave. Furthermore, the extended 2D array also rotates the polarization direction and propagation direction for the vertical incident plane-wave. The radiation beam operates strong multipoles in the 2D array plane at resonant frequency (behaving non-conventionally). Nevertheless, it forms a clear main beam in the incident direction when it deviates from the resonance frequency (behaving conventionally). The proposed array model may have possible applications in nano-amplifiers, nano-sensors and other integrated optics.
RESUMO
OBJECTIVES: This study aimed to investigate various healthcare provisions for women affected with tuberculosis (TB) from low socioeconomic status and their health seeking behaviors, also whether or not patients feel stigmatized about their disease. INTRODUCTION: Pulmonary tuberculosis has more prevalence in Pakistan as compared to western countries where it occurs predominantly in the immunocompromised individuals and immigrants of certain countries. It is a contagious disease and Pakistan stands at the fifth position with maximum reported cases each year. METHODS: A cross-sectional study was carried at Gulab Devi Hospital, a public sector hospital located in Lahore, through a questionnaire-based survey followed by interviewing all participants. Two hundred seventy-seven female patients, who were already diagnosed with pulmonary tuberculosis, were included in the study. The sample was drawn by non-probability, convenience sampling. Literacy, a major contributor to socioeconomic status, was taken primary criteria to select the sample for the study. RESULTS: The study shows that literacy of patients has no impact on whether they feel stigmatized due to their disease as 42% (45 out of 108) of the literate women felt stigmatized while 39% (65 out of 169) of illiterate women also presented with similar feelings. Furthermore, the research also showed that these patients have no effect on requiring permission for going to the health facility as the study revealed that 62% (67 out of 108) in the literate women required permission while 67% (113 out of 169) illiterate women required permission. CONCLUSION: Pakistani population must be educated about TB and factors associated with the progression and consequences of the disease. It was noted that even educated people feel embarrassed when they develop symptoms of TB, thereby causing the unprecedented delay in effective disease management. To conclude, TB clinic should be opened in each community so that people have easy access to treatment of the disease.
RESUMO
This paper reports a new architecture for variable gain-bandwidth amplification of neural signals to be used in implantable multi-channel recording systems. The two most critical requirements in such a front-end circuit are low power consumption and chip area, especially as number of channels increases. The presented architecture employs a single super-performing amplifier, with tunable gain and bandwidth, combined with several low-key preamplifiers and multiplexors for multi-channel recordings. This is in contrast to using copies of high performing amplifier for each channel as is typically reported in earlier literature. The resulting circuits consume lower power and require smaller area as compared to existing designs. Designed in 0.5 µmCMOS, the 8-channel prototype can simultaneously record Local Field Potentials and neural spikes, with an effective power consumption of 3.5 µW per channel and net core area of 0.407 mm(2).