Numerical Modeling of Silicon Photodiodes for High-Accuracy Applications Part III: Interpolating and Extrapolating Internal Quantum-Efficiency Calibrations

The semiconductor device modeling program PC-ID and the programs that support its use in high-accuracy modeling of photodiodes, all of which were described in Part I of this series of papers, are used to simulate the interpolation of high-accuracy internal quantum-efficiency calibrations in the spectral region between 450 nm and 850 nm. Convenient interpolation formulae that depend only upon wavelength are derived. Uncertainty spectra for a number of sources of error are also derived. The formulae are normalized to experimental internal-quantum efficiency calibrations in the 440 to 470 nm spectral region and at 860 nm and arc used to interpolate the calibration values between these wavelengths. The results of the interpolations are compared with experimental calibration data that are available at a few wavelengths between 440 and 860 nm. The disagreement between the interpolated and measured internal quantum-efficiency data is never worse than 0.0003.

Numerical Modeling of Silicon Photodiodes for High-Accuracy Applications Part I. Simulation Programs

The suitability of the semiconductor-device modeling program PC-1D for high-accuracy simulation of silicon photodiodes is discussed. A set of user interface programs optimized to support high-accuracy batch-mode operation of PC-1D for modeling the internal quantum efficiency of photodiodes is also described. The optimization includes correction for the dark current under reverse- and forward-bias conditions before calculating the quantum efficiency, and easy access to the highest numerical accuracy available from PC-1D, neither of which is conveniently available with PC-1D's standard user interface.

Numerical Modeling of Silicon Photodiodes for High-Accuracy Applications Part II. Interpreting Oxide-Bias Experiments

The semiconductor device modeling program PC-1D and the programs that support its use in high-accuracy modeling of photodiodes, all of which were described in Part I of this series of papers, are used to simulate oxide-bias self-calibration experiments on three different types of silicon photodiodes. It is shown that these simulations can be used to determine photodiode characteristics, including the internal quantum efficiency for the different types of photodiodes. In the latter case, the simulations provide more accurate values than can be determined by using the conventional data reduction procedure, and an uncertainty estimate can be derived. Finally, it is shown that 0.9997 ± 0.0003 is a nominal value for the internal quantum efficiency of one type of photodiode over the 440 to 460 nm spectral region.

Adenocarcinoma of the colon and rectum in patients less than 40 years of age

From 1962 to 1988, 50 of 801 patients with adenocarcinoma of the colon and rectum treated at the National Naval Medical Center were less than 40 years old. Symptoms were present in 47 of the younger patients at presentation. The mean duration of time from the onset of symptoms to diagnosis in this group was 4.9 months. Risk factors for carcinoma of the colon and rectum were identified in 14 of 50 patients less than 40 years old. A significantly greater proportion of patients less than 40 years old had Stage C disease compared with the older group of patients (42 versus 22 per cent, p = 0.014). Stage B disease was more common in patients more than 40 years of age (44.8 versus 26.0 per cent, p = 0.014). The proportion of patients with Stages A and D disease was similar in both age groups. The cumulative survival rate in this group at five and ten years was 43 and 34 per cent, respectively. The five year survival rate in patients less than 40 years old with Stage B disease was 76 per cent and with Stage C disease, 37 per cent. All young patients with Stage D disease were dead at 28 months. Synchronous and metachronous carcinomas of the colon and rectum were uncommon in patients less than 40 years old. Patients less than 40 years of age with carcinoma of the colon and rectum are usually symptomatic and have advanced disease at the time of presentation. Survival time for these patients for each stage of disease is similar to the over-all population of patients with carcinoma of the colon and rectum.

Occupational therapy in acute inpatient psychiatry: an activities health approach

This article discusses some of the challenges that occupational therapists working in acute psychiatric inpatient settings commonly face. There is often a lack of sufficient time available for treatment as well as limitations inherent in addressing functional problems in the artificiality of a hospital environment. A theoretical framework is introduced from which the role of occupational therapy and realistic objectives for acute short-term care can be identified. This framework for inpatient occupational therapy practice is based on the concept of activities health, which provides a definition of health in functional rather than medical terms. The importance of emphasizing the patient's competence in roles assumed in community living is emphasized. A step-by-step approach to program development with specific examples is also provided.

Outpatient hemorrhoidectomy

Fifty-three patients underwent closed hemorrhoidectomies on an outpatient basis at the Naval Hospital Bethesda, Bethesda, Maryland, and George Washington University Hospital, Washington, DC. Our goal was to show that closed hemorrhoidectomies could be tolerated well in an outpatient setting. We found that patients tolerated this surgery well, and there was no progression of complications due to the out-of-hospital setting. An additional benefit is the cost savings to the patient who does not require an overnight hospitalization. Outpatient hemorrhoidectomy is a technique that can be effectively used in an ambulatory surgical setting with good patient tolerance and acceptance.

Gastroduodenal polyps in familial polyposis coli

This endoscopic evaluation of 25 patients with familial polyposis coli (FPC) further establishes gastro-duodenal polyps as a significant extracolonic manifestation of the condition. Ten patients had polyps, distributed as follows: stomach (2), duodenum (4), stomach and duodenum (4). Altogether, there were six gastric and seven duodenal lesions. Half of the gastric tumors were hyperplastic and half were adenomatous. All the duodenal tumors were adenomatous, four being ampullary. The one symptomatic patient had intra-polypoid adenocarcinoma. There were no significant correlations between the endoscopic findings and patient age, sex, presence of colon cancer, or other extracolonic abnormalities. The authors affirm that gastroduodenal polyps are an important component of FPC and recommend that all patients with this condition undergo initial and follow-up gastroduodenoscopy. Multiple small lesions may be carefully monitored, but larger ones, particularly those in the region of the ampulla, must be excised.

Extended high temperature measurements of absorption at 10.4 microm in CO(2)

Measurements of absorption by the P(14)-P(24) 10.4-microm CO(2) laser transitions have been performed at 200 Torr at temperatures from 540 to 775 K. Using these results plus earlier data, empirical curves describing the absorption coefficients as a function of temperature are determined over the temperature range from 295 to 775 K. Comparison of model predictions with experiment is made and a discussion of the divergence between them is given.

Anorectal abscess and fistula-in-ano

The etiology of anorectal abscess and fistula-in-ano is discussed. The anatomy, which is vital to the understanding and treatment of the above, is reviewed, with two of the more common classifications of fistula-in-ano presented. The different methods of treating each are discussed, and some of the common complications of the procedure are listed. A true understanding of the disease process and anatomy is needed before treatment of fistulous abscesses is begun, but, with it, successful outcomes will occur in most cases.

Therapeutic colonoscopy in the treatment of colonic pseudo-obstruction

Colonic pseudo-obstruction has been recognized since Ogilvie described this disease in 1948. Metabolic, surgical, and medical causes have been implicated at various times. Treatment has included surgical decompression by cecostomy and colectomy. Successful nonoperative decompression by colonoscopy was first reported by Kukora and Dent in 1977. Since that report several authors have reported their results using this technique. Presented here is a series of nine patients with colonic pseudo-obstruction treated initially with colonoscopy. Patients presented with a variety of associated conditions, including post operative patients, orthopedic injuries, metastatic carcinoma, and an unusual case after a normal vaginal delivery. Eight patients responded well to colonoscopic decompression. One patient, the second in the series, was unable to be decompressed with colonoscopy and underwent a cecostomy under local anesthesia. Successive colonoscopy may be required to allow restoration of normal colonic function, as was the case in seven of our patients. One death occurred, due to unrelated causes. The authors have found colonoscopy to be a safe and reliable therapy for colonic pseudo-obstruction.

Temperature variation of linewidth of the CO2 laser P(16) transition

The halfwidth of the P(16) CO2 laser transition has been measured over a temperature range from 373 to 620 K at pressures varying from 20 to 100 Torr. A Voigt profile line shape was fitted to the experimental absorption coefficient to determine the variation of halfwidth with temperature. The pressure broadened halfwidth varied as T(-0.56) over this temperature range.

Absorption of 9.6-micron CO2 laser radiation by CO2 at elevated temperatures

Absorption of 9.6-micron CO2 laser radiation by CO2 at temperatures between 296 and 625 K has been measured at a pressure of 200 Torr. Experimental results for the R1O-R26 and P1O-P28 transitions have been obtained and compared with computed values of absorption. The relative optical broadening coefficients due to He and N2 have been measured on the R16-R22 and P16-P22 transitions over the same temperature range.

High temperature 10.4-microm absorption in CO(2)-He-N(2) mixtures

Absorption coefficient measurements in CO(2)-He-N(2) mixtures have been performed over the 295-650-K temperature range at four wavelengths of the 10.4-microm CO(2) laser transition. Calculated values of the absorption coefficient were compared with the measured values for fifteen gas mixtures and agreed to >10%. A gas mixture interpolation scheme allows an accurate estimation of absorption by gas mixtures other than those on which measurements were made. A less accurate but simpler interpolation method, dependent only on the fraction of C0(2), is also discussed for determining the absorption coefficient.

Alterations in the rate of lipogenesis in vivo in maternal liver and adipose tissue on premature weaning of lactating rats: a possible regulatory role of prolactin

Removal of pups for 24 h from rats at peak lactation decreased 3H2O incorporation into lipid in vivo in mammary gland by 95%, whereas it was increased in liver (77%) and adipose tissue (330%). These increases were prevented by administration of prolactin. Plasma insulin increased 3-fold on weaning and this was partially prevented by prolactin.

High temperature absorption in the 10.4-mum band of CO(2)

The absorption coefficient of pure CO(2) has been measured as a function of temperature in the 295-650 K range for the P(14)-P(24) and R(10)-R(24) laser transitions. Cubic curves fitted to the experimental results are given to allow interpolation at all temperatures within the range. The P(20) transition shows an anomolously high value of absorption. Variation of absorption coefficient with pressure was linear but small for all transitions in the 200-700-Torr pressure range at three temperatures. Calculations of the absorption coefficient are performed and compared with experimental data.

Utlization of D-3-hydroxy[3-14C]butyrate for lipogenesis in vivo in lactating rat mammary gland

Incorporation of D-3-hydroxy[3-14C]butyrate into lipid in vivo suggests that lactating mammary gland is a major site of ketone-body utilization. The incorporation decreases in short-term insulin deficiency (2h) and on starvation (24h), but increases again on refeeding (2h). The activity of cytosolic acetoacetyl-CoA synthetase parallels the changes in nutritional state, but is not affected by short-term insulin deficiency.