Generalized Tunstall codes for sources with memory

Tunstall codes are variable-to-fixed length codes that maximize the expected number of source letters per dictionary string for discrete, memoryless sources. We analyze a generalization of Tunstall coding to sources with memory and demonstrate that as the dictionary size increases, the number of code letters per source symbol comes arbitrarily close to the minimum among all variable-to-fixed length codes of the same size. We also find the asymptotic relationship between the dictionary size and the average length of a dictionary entry     

Cholescintigraphy in the diagnosis of Rotor syndrome

A 2-year-old boy with Rotor syndrome was studied with Tc-99m N-(di-isopropylphenyl carbamoylmethyl) iminodiacetic acid (DIPA). In this patient, the liver was not visualized, and there was persistent visualization of the cardiac blood pool and along with prominent kidney excretion. It is concluded that Tc-99m DIPA cholescintigraphy may be helpful in the diagnosis of Rotor syndrome.     

Scalar quantisation using a fast systolic array

A systolic array capable of outperforming a table look-up quantiser is proposed. The design has high throughput, can perform uniform or non-uniform quantisation and is suitable for VLSI or field programmable gate array (FPGA) implementation. In the latter case, the array can be used dynamically to both reduce latency and switch between quantisers without the need to reset look-up tables     

Photoacoustic spectroscopy of condensed media with a phase transition

The gas-microphone method of recording a photoacoustic (PA) Rosencwaig—Herschow signal is extended theoretically for consideration of material evaporation of a sample. For an excitation source of constant intensity and exponential saturation of vapor concentration, relations are derived to describe the transient dynamics of the PA response. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 70, No. 1, pp. 153–155, January–February, 1997.     

A time-frequency analysis method for radar scattering

A time-frequency analysis method to study electromagnetic scattering is presented and demonstrated using canonical objects. The time-frequency analysis method utilizes the Bargmann transform to formulate the signal representation in phase space. The use of the Bargmann transform leads to an attractive parametric signal representation in terms of complex polynomials, and elliptical filters can be constructed to crop or extract selected areas of the phase plane. The signal representation and filtering operations are demonstrated using scattering responses from spheres and thin wires, and the prominent scattering features are identified and extracted     

Causes of Decay of Fresh-cut Celery

A decay of fresh-cut celery (Apium graveolens) segments stored at < 5°C in sealed film bags began with a water soaking of the cut surfaces. Slimy moisture accumulated inside the bags. The segments water soaked completely, softened, discolored and sometimes disintegrated. Total aerobic bacterial populations isolated from decayed segments ranged from log₁₀ 7.0–7.7 CFU/g tissue weight. The predominant bacteria, identified by fatty acid analysis as Pseudomonas fluorescens and P. marginalis, caused water soaking, soft rot, and discoloration in freshly inoculated celery tissues stored at 5 or 25°C. Leuconostoc mesenteroides was also isolated and may have been responsible for slime production.     

Integrated imaging for neurosurgery

The authors address using the concept of multimodal bioimage integration at the local area network level, using 3D MRI and PET data of the human head. Here, integration is intended between structural and functional multidimensional images of the same body area of a patient. They analyze the role of present technology and standards (such as the X Window protocol) in providing the physician with a better understanding of the structure-to-function relationships of a given biological organ. They analyze the concept of integration intended as a tool to extract the significative information content from bioimages, i.e. to perform image analysis. The fusion of visual eidetic and linguistic knowledge, which plays an important role in medical diagnosis formation, is seen as a significant step towards obtaining quantitative evaluation of the relevant information content of bioimages     

Obesity, hypertension and atherosclerosis

OBJECTIVE: To determine the effect on oxygen saturation of instilling a saline bolus into artificial airways prior to suctioning, as measured by pulse oximeter. DESIGN: Quasi-experimental, single-case, counterbalanced design. SETTING: The surgical, medical and coronary intensive care units of a federal, teaching medical center. SUBJECTS: Subjects were 40 men, more than 40 years old, in need of intensive care nursing and mechanical ventilation. INTERVENTIONS: Subjects were suctioned as needed for 24 hours. A 5-mL saline bolus was instilled every other time the subject was suctioned. Outcome measurements were done immediately before and after suctioning and at 1-minute intervals for 5 minutes after suctioning. MAIN OUTCOME MEASURES: Noninvasive oxygen saturation values. RESULTS: The instillation of a saline bolus was found to have an adverse effect on oxygen saturation that worsened over time. Significant changes in oxygen saturation as a result of saline bolus instillation were found at 2,3,4 and 5 minutes after instillation. CONCLUSIONS: These results indicate that instilling saline prior to suctioning has an adverse effect on oxygen saturation. These results support the recommendation that the practice of instilling saline prior to suctioning should be abandoned as a routine procedure. More study is needed to investigate whether a specific group of patients may actually benefit from this procedure.