Biophotonic sensor for swift detection of malignant brain tissues by using nanocomposite YBa2Cu3O7/dielectric material as a 1D defective photonic crystal.

In the present research work we have theoretically examined the biosensing capabilities of proposed one dimensional defective photonic crystal for swift detection of malignant brain tissues. The transfer matrix formulation and MATLAB computational tool have been used to examine the transmission properties of proposed structure. The identical buffer layers of nanocomposite superconducting material have been used either side of cavity region to enhance the interaction between incident light and different brain tissue samples poured into the cavity region. All the investigations have been carried out under normal incidence to suppress the experimental liabilities involved. We have investigated the biosensing performance of the proposed design by changing the values of two internal parameters (1) the cavity layer thickness (d4) and (2) volume fraction (η) of nanocomposite buffer layers one by one to get the optimum biosensing performance from the structure. It has been found that the sensitivity of the proposed design becomes 1.42607 µm/RIU when the cavity region of thickness 15dd is loaded with lymphoma brain tissue. This value of sensitivity can be further increased to 2.66136 µm/RIU with η = 0.8. The findings of this work are very beneficial for designing of various bio-sensing structures composed of nanocomposite materials of diversified biomedical applications.

Swelling behaviour of poly(methylmethacrylate) thick resist layers in deep X-ray lithography.

The understanding and optimization of lithographic conditions are particularly important for irradiation of thick resist layers in deep X-ray lithography. The causes and consequences of radiation-induced formation and accumulation of gaseous species inside the poly(methylmethacrylate) (PMMA) resist matrix are discussed. Thick PMMA layers were exposed to high-energy photons from a bending-magnet beamline at the Center for Advanced Microstructures and Devices (CAMD). The focus of this work was to explore the swelling behaviour of PMMA resist of thickness between 50 micro m and 1.6 mm. The influence of various exposure parameters, such as photon energy, filtering conditions, electron current in the storage ring, scan length and scan speed, exposure atmosphere etc., on the swelling of the resist are discussed. The effect of pre-exposure annealing of the PMMA sheets and of temperature variation during irradiation was also investigated. Exposure with optimized X-ray spectral distribution, incident power density, absorbed dose and rate of energy deposition inside the resist allowed swelling of the resist to be minimized during exposure.

Micromachining in plastics using X-ray lithography for the fabrication of microelectrophoresis devices.

Micromachining was performed in polymethylmethacrylate (PMMA) using X-ray lithography for the fabrication of miniaturized devices (microchips) for potential applications in chemical and genetic analyses. The devices were fabricated using two different techniques: transfer mask technology and a Kapton mask. For both processes, the channel topography was transferred (1:1) to the appropriate substrate via the use of an optical mask. In the case of the transfer mask technique, the PMMA substrate was coated with a positive photoresist and a thin Au/Cr plating base. Following UV exposure, the resist was developed and a thick overlayer (approximately 3 microns) of Au electroplated onto the PMMA substrate only where the resist was removed, which acted as an absorber of the X-rays. In the other technique, a Kapton film was used as the X-ray mask. In this case, the Kapton film was UV exposed using the optical mask to define the channel topography and following development of the resist, a thick Au overlayer (8 microns) was electrodeposited onto the Kapton sheet. The PMMA wafer during X-ray exposure was situated directly underneath the Kapton mask. In both cases, the PMMA wafer was exposed to soft X-rays and developed to remove the exposed PMMA. The resulting channels were found to be 20 microns in width (determined by optical mask) with channel depths of approximately 50 microns (determined by x-ray exposure time). In order to demonstrate the utility of this micromachining process, several components were fabricated in PMMA including capillary/chip connectors, injectors for fixed-volume sample introduction, separation channels for electrophoresis and integrated fiber optic fluorescence detectors. These components could be integrated into a single device to assemble a system appropriate for the rapid analysis of various targets.

Deep X-ray lithography with a tunable wavelength shifter at CAMD.

An additional X-ray lithography facility is under construction at the Center for Advanced Microstructures and Devices. It will receive radiation from a 7.5 T superconducting three-pole wavelength shifter. The critical energy of the insertion device is tunable up to a maximum value of 11.2 keV, allowing for optimization of photon spectra to resist thickness. In particular, this hard X-ray source will allow investigation of X-ray lithography at very high energies for devices with thicknesses in excess of 1 mm, and study of low-cost mass-production concepts, using simultaneously exposed stacks of resist layers.

Pain management documenting the decision making process.

From patient admission to discharge, pain is a critical symptom of concern to the nurse case manager. This descriptive study examined nurses' decision-making regarding pain management as documented in clinical records of patients after orthopedic surgery. Using a Nurses' Pain Management Audit Tool, data analysis revealed that during the first 24 hours after emergence from the Post-Anesthesia Care Unit, these patients received less than 50% of the narcotic doses available for their pain relief. Nurses documented less than 25% of the "ideal occurrences" possible for pain assessment, as described in the Agency for Health Care Policy and Research Guidelines. Incomplete databases for guiding patient outcomes of effective pain management were perpetuated by insufficient documentation. Nurse case managers could stimulate increased commitment and quality improvement in pain management as a crucial aspect of patient care.

[The value of radiological screening in the Tunisian army]. / Intérêt du radio-dépistage dans l'armée tunisienne.

In a non orientated study of 12,357 radio-detecting of the new recruits the authors noticed that tuberculosis is still occupying a privileged place despite the effort made for prevention, and a retreat of post-infectious bronchiectasis of childhood. The authors underline the necessity to continue systematic detecting despite the low percentage of restrained anomalies, this is for two reasons: *on the one hand to avoid the little tuberculosis epidemic of the barracks *on the other hand for an early treatment of the other affections especially heart affections.

A review of microfabrication technologies: application to x-ray optics.

We present an outline of various microfabrication techniques and processes, particularly for applications to x-ray optics. Emphasis is placed on both high resolution diffractive components such as gratings and zone plates and multidimensional reflective diffracting structures using multilayer interference mirrors. Some selected examples are also discussed.