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You don't need an M.B.A. to know that to thrive in today's competitive market, you need to run your practice like a business. It's a matter of keeping productivity high, while holding the line on costs and stress.     

Molecular cloning of a zinc finger gene eZNF from a human inner ear cDNA library, and in situ expression pattern of its mouse homologue in mouse inner ear

A mathematical model of posttetanic processes launched by rhythmic stimulation of the excitatory and inhibitory inputs to the dendritic spine of a pyramidal neuron in hippocampal field CA3 was used to study conditions for modifying the efficiency of the inhibitory input. The level of dephosphorylation of GABAa and GABAb receptors, which determines the GABA sensitivity of these receptors, was shown to depend on the Ca(2+)-dependent ratio of active protein kinases and protein phosphatases; the level of dephosphorylation decreased monotonically as the intracellular Ca2+ increased. Posttetanic increases and decreases in the Ca2+ concentration, as compared with the level achieved during the previous stimulation, led to increases or decreases respectively in the number of dephosphorylated GABA receptors and to induction of long-term potentiation and depression, respectively, in the efficiency of inhibitory transmission. The extent of the modification effect depended on the ratio of the quantities of inhibitory and excitatory mediators in the synaptic cleft. At very low or very high GABA concentrations, modification of inhibitory transmission was insignificant.     

Autonomic motor neuron migration and expression of nicotinamide adenine dinucleotide phosphate reduced diaphorase are dependent upon peripheral target

The mechanical behavior of calf pericardium employed in the manufacture of cardiac bioprostheses was assessed according to the region from which it was selected. For this purpose, selected samples of the tissue were sewn with different types of commercially available sutures and subjected to tensile testing, the results of which were compared with the findings in selected, but not sutured, tissue used as a control. The results confirm a loss of resistance--that is, a reduction of the capacity of sutured samples of the biomaterial to withstand breakage stress compared with control samples. Taking into account the marked resistance to breakage of the suture thread, this phenomenon can only be explained as a consequence of the deleterious mechanical interaction between the suture and chemically treated pericardium. This interaction is illustrated by the shearing force which is responsible for the loss of resistance in the tested samples. These trials demonstrate that the results can be improved and the deleterious interaction diminished, although not eliminated, when the pericardium is selected from a given region.     

Treatment-induced mucositis: an old problem with new remedies

Mucositis may be a painful, debilitating, dose-limiting side-effect of both chemotherapy and radiotherapy for which there is no widely accepted prophylaxis or effective treatment. The basis of management is pain relief, prevention of dehydration and adequate nutrition. When tested vigorously, most antiseptic mouthwashes and anti-ulcer agents are ineffective. Simple mechanical cleansing by saline is the most effective traditional measure. A variety of new agents are effective. Granulocyte macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) act outwith the haemopoeitic system and can reduce mucositis, but the best schedule, dosage and method of administration is not known or which is the best growth factor to prevent this side-effect. A placebo-controlled randomized trial of antibiotic pastilles has shown a significant reduction in mucositis and weight loss during radiotherapy for head and neck cancer. Another method to reduce radiation effects in normal tissue is to stimulate cells to divide before radiotherapy by silver nitrate or interleukin 1. These methods may be particularly effective when given along with hyperfractionated radiation treatment such as CHART.     

Passive immunization of newborn rhesus macaques prevents oral simian immunodeficiency virus infection

To determine if passively acquired antiviral antibodies modulate virus transmission and disease progression in human pediatric AIDS, the potential of pre- and postexposure passive immunization with hyperimmune serum to prevent oral simian immunodeficiency virus (SIV) infection or disease progression in newborn rhesus macaques was tested. Untreated neonates became infected after oral SIV inoculation and had high viremia, and most animals developed fatal AIDS within 3 months. In contrast, SIV hyperimmune serum given subcutaneously prior to oral SIV inoculation protected 6 newborns against infection. When this SIV hyperimmune serum was given to 3 newborns 3 weeks after oral SIV inoculation, viremia was not reduced, and all 3 infants died within 3 months of age due to AIDS and immune-complex disease. These results suggest that passively acquired antihuman immunodeficiency virus (HIV) IgG may decrease perinatal HIV transmission. However, anti-HIV IgG may not impart therapeutic benefit to infants with established HIV infection.     

Understanding deafness as a culture with a unique language and not a disability

The traditional view of deafness and deaf patients and families is based on a pathological perspective of deafness rather than a cultural perspective. The purpose of this article is to offer advanced practice nurses an alternative approach to this often misunderstood community of patients who have their own unique language, values, and experiences.     

Growth of InAs Quantum Dots on Germanium Substrate Using Metal Organic Chemical Vapor Deposition Technique

Self-assembled InAs quantum dots (QDs) were grown on germanium substrates by metal organic chemical vapor deposition technique. Effects of growth temperature and InAs coverage on the size, density, and height of quantum dots were investigated. Growth temperature was varied from 400 to 450 °C and InAs coverage was varied between 1.40 and 2.35 monolayers (MLs). The surface morphology and structural characteristics of the quantum dots analyzed by atomic force microscope revealed that the density of the InAs quantum dots first increased and then decreased with the amount of InAs coverage; whereas density decreased with increase in growth temperature. It was observed that the size and height of InAs quantum dots increased with increase in both temperature and InAs coverage. The density of QDs was effectively controlled by growth temperature and InAs coverage on GaAs buffer layer.     

Cryptanalysis of optical security systems with significant output images

The security of the encryption and verification techniques with significant output images is examined by a known-plaintext attack. We introduce an iterative phase-retrieval algorithm based on multiple intensity measurements to heuristically estimate the phase key in the Fourier domain by several plaintext-cyphertext pairs. We obtain correlation output images with very low error by correlating the estimated key with corresponding random phase masks. Our studies show that the convergence behavior of this algorithm sensitively depends on the starting point. We also demonstrate that this algorithm can be used to attack the double random phase encoding technique.     

Fundamental diffraction limitations in a paraxial 4-f imaging system with coherent and incoherent illumination

In the usual model of an imaging system, only the effects of the aperture stop are considered in determining diffraction-limited system performance. In fact, diffraction at other stops--those associated with different lens elements, for example--can also affect system performance and cause the imaging to be space variant, even in the absence of vignetting in the conventional ray optics sense. For the 4-f imaging system investigated in this paper, the severity of the space variance depends on the relative sizes of the two lens stops and the aperture stops. If the diameters of the lenses are equal, the aperture of the first lens has a greater effect on system performance than does that of the second.     

In-Plane Integration of Polymer Microfluidic Channels With Optical Waveguides– A Preliminary Investigation

The next major challenges for lab-on-a-chip (LoC) technology are 1) the integration of microfluidics with optical detection technologies and 2) the large-scale production of devices at a low cost. In this paper the fabrication and characterisation of a simple optical LoC platform comprising integrated multimode waveguides and microfluidic channels based on a photo-patternable acrylate based polymer is reported. The polymer can be patterned into both waveguides and microfluidic channels using photolithography. Devices are therefore both quick and cost-effective to fabricate, resulting in chips that are potentially disposable. The devices are designed to be highly sensitive, using an in-plane direct excitation configuration in which waveguides intersect the microfluidic channel orthogonally. The waveguides are used both to guide the excitation light and to collect the fluorescence signal from the analyte. The potential of the device to be used for fluorescence measurements is demonstrated using an aqueous solution of sodium fluorescein. A detection limit of 7 nM is achieved. The possibilities offered by such a device design, in providing a cost-effective and disposable measurement system based on the integration of optical waveguides with LoC technology is discussed.