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The objective is to assess impact of fluid removal on improvement in organ function in children who received continuous renal replacement therapy (CRRT) for management of acute kidney injury and/or fluid overload (FO). A retrospective review of eligible patients admitted to a tertiary level intensive care unit over a 3-year period was performed. Improvement in nonrenal organ function, the primary outcome, was defined as decrease in nonrenal component of Pediatric Logistic Organ Dysfunction (PELOD) score on day 3 of CRRT. The cohort was categorized into Group 1 (improvement) and Group 2 (no improvement or worsening) in nonrenal PELOD score. Multivariable logistic regression analysis was performed to identify independent predictors. A higher PELOD score at CRRT initiation (odds ratio [OR]: 1.11, 95% confidence interval [CI]: 1.05, 1.18, p

Introduction The aim of this study was to determine whether ultrasound alone is sufficient to safely exclude malignancy in thyroid nodules in a district general hospital setting, to comply with the latest British Thyroid Association guidelines. Methods This retrospective study investigated the quality of ultrasound reporting and the correlation between ultrasound report and histology for individual thyroid nodules. Cases were selected from the thyroid multidisciplinary meeting and included all patients having undergone surgery for a thyroid malignancy in a one-year period. Results Forty-seven patients were included in the study. Ultrasound reports were reviewed and assessed, in which 21 clinicians were involved; 36% of scans included a summary of whether the nodule(s) overall appeared benign, equivocal, suspicious or malignant; 4% of reports included a U classification; 81% of reports commented on cervical lymph nodes. Ultrasound was compared with histology. The sensitivity of ultrasound in correctly identifying nodules requiring further investigation was of 56% and specificity was 81%. Positive predictive value was 81% and negative predictive value was 56%. Discussion These findings suggest that, in a district general hospital setting without a dedicated head and neck radiologist, using only ultrasound and limiting fine-needle aspiration cytology to identify suspicious nodules may not be safe, as a high number of nodules appearing benign on ultrasound may ultimately prove to be malignant.

Though nasal continuous positive airway pressure (NCPAP) is commonly used for non-invasive neonatal respiratory support, the optimal method of weaning NCPAP is not established. In this prospective, two-center randomized control trial we hypothesize that gradually increasing spontaneous breathing time off NCPAP increases successful weaning from NCPAP in infants born31 weeks gestational age.Infants were randomized to one of the two NCPAP weaning protocols, a sprinting, that is, gradually increasing spontaneous breathing time off CPAP, protocol vs a non-sprinting (weaning pressure down) protocol.Eighty-six infants were enrolled in one of the two study groups. Thirty-one infants (77%) in the sprinting group and 30 (75%) in the non-sprinting group were successfully weaned off NCPAP at the first attempt (P0.05). It took 1.3 (1 to 1.75) (median (IQR)) attempts and 7 (7 to 7) days to wean NCPAP off in the sprinting group vs 1.3 (1 to 1.75) attempts and 7 (7 to 10) days in the non-sprinting group (P0.05). Additionally, no differences in the secondary outcomes of bronchopulmonary dysplasia, severe retinopathy of prematurity (⩾stage 3), periventricular leukomalacia and length of stay were noted between the two groups.Weaning NCPAP via sprinting or non-sprinting protocol is comparable, not only for successful weaning but also for the occurrence of common neonatal morbidities that impact the long-term outcome in premature infants (ClinicalTrials.gov number, NCT02819050).

Cyclin-dependent kinase 4/6 inhibitors, which act by inhibiting progression from the G1 to S phases of the cell cycle, include palbociclib, ribociclib, abemaciclib, and trilaciclib. Palbociclib and ribociclib are currently food and drug administration-approved for use in combination with aromatase inhibitors in postmenopausal women with metastatic hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer. Palbociclib is also food and drug administration-approved for use in combination with fulvestrant in hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer progressing after endocrine therapy. Abemaciclib is the newest cyclin-dependent kinase 4/6 inhibitor to gain Food and Drug Administration (FDA) approval, specifically as monotherapy for hormone receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer previously treated with chemotherapy and endocrine therapy. Abemaciclib also shares a similar indication with palbociclib for use in combination with fulvestrant in hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer progressing after endocrine therapy. Trilaciclib use remains largely investigational at this time. However, despite FDA-approval for only metastatic hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer, all four cyclin-dependent kinase 4/6 inhibitors have shown promise in hematologic malignancies and non-breast solid tumors. Although further research is needed, cyclin-dependent kinase 4/6 inhibitors represent intriguing developments in the treatment of various malignancies, including those with such poor prognoses as glioblastoma multiforme, mantle cell lymphoma, and metastatic melanoma. We discuss the approved indications, current research, and areas of future exploration for palbociclib, ribociclib, abemaciclib, and trilaciclib.

A review of high operating temperature (HOT) infrared (IR) photon detector technology vis-a-vis material requirements, device design and state of the art achieved is presented in this article. The HOT photon detector concept offers the promise of operation at temperatures above 120 K to near room temperature. Advantages are reduction in system size, weight, cost and increase in system reliability. A theoretical study of the thermal generation-recombination (g-r) processes such as Auger and defect related Shockley Read Hall (SRH) recombination responsible for increasing dark current in HgCdTe detectors is presented. Results of theoretical analysis are used to evaluate performance of long wavelength (LW) and mid wavelength (MW) IR detectors at high operating temperatures. (C) 2013 Elsevier B.V. All rights reserved.

We present a method of analyzing the non-uniformity in electrical characteristics of HgCdTe photodiode arrays for infrared imaging applications. We have selected dynamic resistance–voltage (R–V) characteristics for analyzing electrical behavior of HgCdTe photodiodes because the dynamic resistance at a given operating voltage directly governs the imager performance and being derivative of current–voltage (I–V) characteristics, it has little impact of the constant shifts due to stray illumination during dark measurements, relaxing the stringent requirement of perfect dark conditions to some extent for performance analysis. We have demonstrated that by using statistical analysis such as correlation of the selected signatures and their principal component analysis, we can identify the root cause of the high non-uniformity among sensor pixels in the array. The method has been implemented using theoretical I–V model of MWIR HgCdTe photodiodes, but it is generic and may be implemented on any other types of diode arrays for theoretical or experimental analysis of their non-uniformity.

Micro-Raman spectroscopy was used to evaluate the surface quality of Hg 1− x Cd x Te ( x = 0.3) epitaxial layers polished with chemo-mechanical and free chemical etching processes. Raman technique has been employed to monitor the HgCdTe detector array fabrication process to ensure epilayer surface devoid of impurities and minimal damage. Chemical etching with bromine–methanol solution is seen to leave residual damage or non-stoichiometric HgCdTe surface layer indicated by an asymmetrical broadening and down shift in all Raman peaks. A peak at 112 cm −1 as defect mode or due to disordering on the epilayer surface has been noticed.

In this paper, the ranges of two specific long-wave infrared (LWIR) and mid-wave infrared (MWIR) focal plane array (FPA) systems are estimated and compared, using MODTRAN to calculate atmospheric transmission and NVTherm to calculate the ranges. The calculations are for a standard tank target, clear weather conditions and a horizontal terrestrial path at mean sea level, under varying ambient temperature and relative humidity (RH) conditions. Detection ranges are more sensitive to temperature and RH variations than the recognition ranges, while identification ranges are the least sensitive. LWIR ranges depend more upon these variations than do MWIR ranges. The relative range ratios are plotted versus the ambient temperature and RH as a contour plot. Typically, LWIR systems perform better at lower ambient temperatures and RHs, while MWIR systems are advantageous at higher temperatures and RHs. The so-called ‘phase curve’ separating the MWIR and LWIR ‘phases’ also depends upon system parameters (FPA and optics). Ambient temperatures and RHs vary diurnally and seasonally, and over kilometer distance scales. Our proposed plot is more flexible than the standard scenarios used in MODTRAN. The advent of dual band imaging systems has not rendered this discussion irrelevant since the more producible FPAs are sequential rather than simultaneous.

We propose a unified approximate analytical expression for the carrier density of HgCdTe semiconductors that have non-parabolic energy bands and are highly degenerate. The proposed expression is without any adjustable parameter. It can be applied to HgCdTe for the case where electron densities are very high and the material is strongly degenerate, e.g., a highly accumulated surface due to passivant-induced negative fixed charge density in an n-HgCdTe photoconductor device. The proposed expression is simultaneously valid for SWIR, MWIR and LWIR bands.

A compositionally graded surface layer has been created for the passivation of Hg1-xCdxTe photodiodes. The graded CdTe-Hg1-xCdxTe interface was created by deposition of CdTe and subsequent annealing. It was found that the composition gradient and width of the graded region could be tailored by adopting a suitable annealing procedure. The effect of grading on the interface electrical properties and photoelectrical properties was studied by X-ray photoelectron spectroscopy (XPS), photoconductive decay, and C-V measurements. Insulator fixed-charge density and interface-trap density could be reduced to 3times1010 cm -2 and 2times1010 cm-2middoteV-1, respectively, by creating a graded interfacial composition. The interface conditions so engineered led to a low surface recombination velocity ~3000 cm/s. A direct correlation has been established between the process conditions, interfacial composition, and the electrical/photoelectrical properties of the CdTe-Hg1-xCdxTe heterostructures. The passivation layer formed by this method is shown to be suitable for the fabrication of high-performance infrared detectors

A compositionally graded CdTe-Hg1−xCdxTe interface was created by deposition of CdTe on p-HgCdTe and subsequent annealing. The compositionally graded layer between CdTe and HgCdTe was formed by an interdiffusion process and was used for passivation. The composition gradient (Δx) in the interfacial region and the width of the graded region were tailored by adopting a suitable annealing procedure. The effect of process conditions on the interfacial profile and photoelectric properties such as lifetime and surface recombination velocity was studied in detail. Surface recombination velocity of the p-HgCdTe could be reduced to the level of 3,000 cm/s at 77 K, which represents very good passivation characteristics. The passivation layer formed by this method can be used for the fabrication of high performance and stable modern infrared detectors. Thus, a passivation process is developed, which is simple, effective, reproducible, and compatible with the HgCdTe device fabrication and packaging processes.

Summary Background Treatment with a continuous i.v. proton pump inhibitor is presumed to promote clot formation and stability by sustaining intragastric pH ≥ 6. Aim We postulated that very frequent oral dosing of proton pump inhibitors should simulate i.v. infusion and achieve similar pH control. Methods Twenty healthy volunteers were stratified by Helicobacter pylori status (10 positive; 10 negative) and had determination of CYP2C19 status. After an overnight fast, an intragastric pH probe was placed. Subjects received 120 mg of lansoprazole at 8 am and 30 mg every 3 h until 8 pm. Intragastric pH was measured over 24 h, and lansoprazole plasma concentrations were determined at five time points. Results Intragastric pH was ≥6 for 41% (95% CI: 30–53%) of the 15-h period from 8 am–11 pm and 46% (95% CI: 35–56%) of the 24-h period (8–8 am). The mean proportion of patients with pH ≥6 was not significantly different in H. pylori-positive vs. negative patients. Only 25% of subjects sustained pH ≥6 for at least 60% of the 15-h period, and 35% had a sustained pH ≥6 for at least 60% of the 24-h period. Conclusions A dose of 120 mg of oral lansoprazole followed by standard 30 mg doses of lansoprazole every 3 h did not reliably sustain pH at the desired level of 6.

We propose simple, analytical, approximations of carrier density for HgCdTe semiconductors that have non-parabolic energy bands and are highly degenerate. The proposed expressions are in the form similar to the classical Boltzmann's approximation without any adjustable parameter. These relations can be applied to HgCdTe for the case where electron densities are very high and the material is highly degenerate, e.g. highly accumulated surface due to passivant induced negative fixed charge density in n-HgCdTe photoconductor device. The expressions are valid in the LWIR and MWIR bands, and can be tuned further to apply to other bands.

We present the results of calculations for surface shunt resistance due to the passivant fixed charge density (Qss) in n-HgCdTe photoconductive (PC) detectors. To the best of our knowledge, this is the first detailed calculation involving the actual majority carrier profile at the accumulated surface. The effect of surface field (or potential) due to heavily accumulated density of majority carriers on surface mobility (μs) has been investigated in detail by employing the Schrieffer and Goldstein models using random diffuse scattering. Additionally, the effect of lateral field (applied to these devices) on surface mobility is included by invoking the model of Yoo et al. The above effects were not taken into account in previous simplified models. For narrow-band, n-type HgCdTe the effects of carrier degeneracy and band non-parabolicity cannot be neglected. In this work, a one-dimensional model including these effects has been developed to evaluate the detector resistance and responsivity. A proper two-layer (bulk and surface) responsivity model is developed. The results are compared with the widely-used approximate one-layer model of Reine and with the step model proposed by Bhan and Gopal. It is shown that, for the Reine model, the agreement with the present model depends on the value of μs chosen. The trend of the step model agrees with the Reine model, but both models show disagreement with the present one-layer and two-layer profile models for Qss ≈ (1010–1012) cm−2.

A long wavelength infrared (LWIR) 2D (mosaic) diode array has been studied by numerically solving the diffusion equation in terms of thermally generated carriers in a n+-on-p HgCdTe diode in an array environment. The results are presented in terms of the resistance–area (RA) product, in the diffusion-limited case. The results are compared with analytical expressions in the limiting case of the infinite diode. For a finite diode, with a definite junction depth, and a diode size that is smaller than the pitch, the RA, obtained from quasi-3D calculations, is smaller than that expected for the infinite diode case, the deviation being greater for small diodes. Commonly in the literature, the theoretical values of the infinite (1D) diode – which are overestimates – are stated as experimental targets. In the present calculations, the volume of the diode is considered to consist of two parts: one that contributes to the lateral diffusion current that is collected by the four lateral faces of the diode junction, and another that is the `normal' diffusion current, collected by the planar part of the junction from the volume `under' the diode. For the infinite diode case, only the latter component exists. The effect of the perimeter-to-area ratio on the RA in an array environment has been studied. The effective diffusion length associated with the finite diode geometry in an array differs from the standard diffusion length.

The dependence of the zero-bias resistance-area (RA) product and the quantum efficiency (η) of variable-area diode arrays is numerically calculated by solving the diffusion equation in a cylindrical, three-dimensional geometry in the thick base approximation. The calculation is done for long-wavelength IR HgCdTe n+-on-p diffusion-limited photodiodes at 77 K. The inverse resistance-area product 1/(RA) and the square root of the quantum efficiency, η1/2, are plotted against the perimeter-to-area (P/A) ratio. The 1/RA results are fitted to a quadratic dependence on the P/A ratio. The dependence of the 1/RA on the minority carrier diffusion length, the junction depth and the surface recombination velocity (SRV) is evaluated. An empirical expression is proposed that largely accounts for the dependence of the coefficients of the quadratic on these parameters and is more general than those used in previous studies. The results are also in reasonable agreement with the results of Briggs, expressed in terms of the parameter f3D, that are valid for zero junction depth and zero SRV. The slope of the quantum efficiency versus P/A plot, which is approximately a straight line, is related to an effective length Lopt, that also depends on the diffusion length, junction depth, SRV and the absorption coefficient α. The parameter Lopt varies as α1/2.

In this paper, the varying composition (x) of the Hg1-xCdxTe epilayer is related to a new parameter namely the shift in the forward bias voltage at a constant current (Vcon) of the photovoltaic (PV) diodes in an array environment. The dependence of Vcon on the composition x is investigated both theoretically and experimentally. It is shown that Vcon is almost linearly proportional to x and hence can be utilized as a calibration standard for mapping x or non-uniformity in x. Here, this is done by fabricating nine 16×16 photovoltaic diode arrays on liquid-phase epitaxy-grown mercury cadmium telluride, Hg1-xCdxTe, of nominal composition x = 0.227. The composition x or cut-off wavelengths (λc) determined from Fourier transform infrared transmission for three specific PV diodes having different compositions (x) are correlated with the shift in Vcon of current-voltage (I-V) characteristics of these diodes. Following this, Vcon versus x is plotted which is used as a calibration curve for mapping non-uniformity in x in terms of Vcon for a given technology. Furthermore, it is proposed that, in addition to the usual information, the I-V characteristics can be used to monitor any process-induced changes in the composition of the starting material.

For realizing HgCdTe focal plane arrays on alternate substrates (Si or GaAs), CdTe buffer layers are essential. Bulk CdTe/CdZnTe substrates are also used for LPE growth of HgCdTe. A model for the effect of the n-CdTe substrate resistivity on the quantum efficiency, /spl eta/, and the dynamic resistance-area product, R/sub d/A, of a n/sup +/-on-p HgCdTe backside illuminated photodiode has been developed, taking into account the effect of the graded heterointerface between CdTe/CdZnTe and HgCdTe on the homojunction photodiode. The issue of how low the substrate/buffer layer resistivity can be, without degrading the performance of the photodiode, has been addressed. For low substrate resistivities, the R/sub d/A can drop by about 50%, while the quantum efficiency decreases by about 5%. It has been found that as low as 2 /spl Omega/-cm for long wavelength IR photodiodes (cutoff wavelength 14 /spl mu/m) is acceptable. To obtain the R/sub d/A and /spl eta/ from the band profile, a linear approximation has been used in which the interface barrier region has a constant electric field, while the bulk of the epilayer has no electric field. General expressions have been derived for the R/sub d/A and /spl eta/ in this two-region model. Our solutions are valid for both high and low electric fields, unlike previously derived solutions in the literature valid either in the one-region low-field case or the two-region, high-field approximation.

The multiplexer functionality of two sets of two-dimensional Charge Coupled Device (CCD) multiplexers (MUXs) viz. 16×16 and 100×100, using identical design tools, on-chip amplifiers, technology and foundry for fabrication, was measured under identical clocking conditions. It was found that the frame readout of the 100×100 CCD MUX shows an anomalous effect, in the sense that video output signal value monotonically decreases as the pixel number increases (from first to last pixel). This was contrary to the expectation of constant output from all the pixels—as was observed for 16×16 CCD MUXs. The problem was analysed by performing a number of experiments (with horizontal and vertical shift registers, input structure, etc.) to isolate the number of reasons/blocks that are possibly responsible for the cause of this effect. The origin of the problem was traced to a polysilicon bus used for interconnecting Store Gates (SGs) of the input structure. The total resistance, and consequently voltage drop, across this bus was found to be negligible for smaller arrays (16×16), but not for larger ones (100×100). By proper tuning of spill time of input injecting pulse, this anomalous effect could be eliminated completely. A simple model for the anomalous effect was developed and the predicted trends found to agree with various experimental observations.

A simple two-dimensional model, for calculating the effect of the built-in electric field arising in HgCdTe epilayers due to the composition gradient that occurs in LPE growth, on the crosstalk is developed for the case of a back illuminated focal plane array. The calculations predict that the crosstalk does not decrease monotonically with increasing electric field (i.e., weak peaks occur), unlike in the simple one-dimensional model of Kamins and Fong. The zero-field crosstalk varies between 1% and 10%, depending upon the material parameters. For electric fields in the range of 1–10 V cm−1, the crosstalk is reduced to negligible values (

Infrared focal plane arrays (IRFPAs) are rapidly increasing in size. It is shown here that for large FPAs a considerable shift in the operating point occurs, which, if not reduced, introduces unacceptably large nonuniformity in the array response. This shift results because of the variable voltage drop across the HgCdTe active layer, due to its finite distributed resistance. A new analytical two-dimensional (2-D) model to estimate the operating point shift of individual detectors of long wavelength infrared (LWIR) HgCdTe focal plane array (FPA) is presented. Avoiding this operating point shift requires an optimized grid pattern.

A dual Chamber RIBER 32P Molecular beam epitaxy (MBE) system was used to grow high quality HgCdTe epilayers. For growth, the critical parameters are: 1) accurate determination and control of real substrate temperature 2) precise identification of the Hg/Te ratios 3) CdZnTe substrates with reproducible surface finish and structural characteristics. Because the substrate holder rotates during growth, the junction of spring-loaded thermocouple does not contact the molyblock leading to irreproducible temperature measurements.

In this paper a model for calculating the quantum efficiency and the specific detectivity of both and photodiodes, considering both front- and backside illuminated configurations, is presented. The diode is analysed by assuming a step model for the concentration profile. The effects of the surface recombination velocities at different surfaces/interfaces of the diode, the minority carrier lifetimes and the carrier concentrations are considered. It is pointed out that the parameter to be optimized for a photodiode is and not the zero-bias resistance - area product , although the latter combines with the quantum efficiency to determine the behaviour of . Based on our calculations, it is observed that the values of different parameters that maximize are different from those that are optimal for high quantum efficiency. For sufficiently high , dominates ; otherwise, both factors affect . The calculation of done here refers to the long-wavelength IR region where often is low, with the result that the injection efficiency into the CCD multiplexer is decreased, which has been taken into account.

Voltage - temperature characteristics of photovoltaic diodes fabricated on HgCdTe epitaxial layers have been studied. The diodes are operated with forward bias in a constant-current mode. Plots of forward voltage versus temperature (T) clearly reveal well resolved peaks suggestive of a trap-assisted tunnelling (TAT) mechanism. The nonlinearity of versus T plots in terms of these peaks correlates with reverse leakage currents and resistance - area products whereas the ideality factor correlates with TAT. Two such peaks are observed in our samples near 120 and 90 K. The origin of these peaks is explained by a multi-step tunnelling recombination model.

The results of a quasi-two-dimensional model for calculating passivant-induced surface leakage currents due to band-to-band tunnelling in mercury cadmium telluride (MCT) photovoltaic (PV) diodes are presented. The object is to assess the effect of a fixed surface state charge density due to a passivant on the zero-bias resistance - area product for the technologically important case when surface state charges accumulate the MCT surface. Calculations are carried out to estimate the tolerable value of beyond which the of the MCT diode degrades. To the best of our knowledge, this is the first time that such a detailed calculation involving the acceptor concentration profile near the surface has been reported for long-wavelength IR (LWIR) MCT photodiodes. This calculation has been done numerically, and hence the depletion width (pinched near the surface), the electric field and the band-to-band tunnelling are calculated as a function of depth, layer by layer, from the passivant - semiconductor interface. The currents - diffusion, generation - recombination, band-to-band and trap-assisted tunnelling - have been calculated in each layer, and the zero-bias resistance - area product is determined for each mechanism. Hence, the resultant is calculated. The results are compared with the earlier step model of Bhan and Gopal (Semicond. Sci. Technol. 9 (1994) 289), which assumed a surface layer of constant concentration . The present model indicates that for photodiodes with a cut-off wavelength of and an acceptor concentration , operating at 77 K, a would degrade significantly. This value is insensitive to composition (in the LWIR). For an diode, the tolerable value of is found to depend on the concentration in the layer. Further, the tolerable value of for an diode is much higher than for an diode, for donor concentrations .

The effect of the layer in a structure made in long-wavelength (x = 0.229) epilayers on the zero-bias resistance - area product is theoretically analysed, and compared with a structure. A step profile is assumed for the concentration in the and layers, fabricated by ion implantation and annealing. Various current components (diffusion currents in the , and p layers, depletion layer and surface generation - recombination (g - r) currents, band-to-band and trap-assisted tunnelling) are taken into account. The effect of the surface recombination velocities, and the concentrations (p-side trap, layer, and p layer) are discussed in detail. The results of this model clearly indicate the conditions under which a diode can perform better than a diode. In broad terms, a structure is more suitable for p-type epilayers with lower trap concentrations and higher lifetimes, whereas a structure is advantageous, in terms of increasing , for higher trap concentrations and lower lifetimes. Another advantage of the structure is that reduced tunnelling implies that a higher acceptor concentration can be accepted for device fabrication.

To increase the detection range in staring FPAs, commonly the integration time Ti is increased, as the range is assumed to increase as one-fourth power of T i , (T i 1 4 ) . It is shown here that the range dependence on Ti is weaker than T i 1 4 , because of the effect of atmosphere. Since the atmospheric transmission coefficient decreases with increasing range, the effect of increasing Ti on the range is considerably reduced. It is also shown that when detector 1/f noise dominates over other noise sources, the dependence of range on Ti is much weaker than T i 1 4 , having a logarithmic dependence Calculations have been done by integrating equations involving spectral functions—photon flux, atmospheric transmission coefficient, optics transmission coefficient and responsivity—over wavelength, in the spectral range from 8 μm to 12 μm. LOWTRAN2 has been used for spectral atmospheric transmission coefficients, for different conditions of ambient temperature (−30°C to 55°C) and relative humidity (50–85%). The range formulation also distinguishes between distant targets (point sources) and nearby targets (extended sources). The analysis is applicable for terrestrial imaging, where the temperature difference of the target and the background is small. The effect of fixed pattern noise (FPN) in mercury cadmium telluride (MCT) FPAs has also been considered by modeling FPN in terms of a composition variation in the MCT. It is seen that range, both in the point source and the extended source cases, is not a sensitive function of FPN.

Twenty patients, diagnosed as suffering from treatment-resistant major depression, were treated with one or more drugs that decrease corticosteroid biosynthesis. Nine were psychotic, 11 nonpsychotic. Seventeen completed the treatment (8 psychotic, 9 nonpsychotic); 13 responded (5 psychotic, 8 nonpsychotic; 11 responded completely (i.e., a drop in the Hamilton Depression Scale of at least 50%, toor = 15), and 2 responded partially. The mean age of the responders (45.2 +/- 12.6 years) did not differ significantly from that of the nonresponders (48.7 +/- 12/3). Data were analyzed in the following categories; (1) the presence or absence of psychosis, (2) response or nonresponse to treatment, and (3) the drug(s) used (aminoglutethimide, ketoconazole, or a combination of either of these with metyrapone). The patients improved over time on the Hamilton Depression Scale independent of the medication used. Responders demonstrated improvement in mood, insomnia, anxiety, diurnal variation, paranoia and obsessive compulsiveness. Nonpsychotics responded better than psychotics.

The influence of dislocations on the electrical and photo-electric characteristics of HgCdTe has been widely discussed in published literature. However, an unexplored aspect of the dislocations that has not yet attracted the attention of any of the investigators, is the band gap narrowing/widening induced by the intense stress field around dislocation core. Preliminary estimations show that the band gap narrowing due to the tensile region of the stress field along the dislocations in HgCdTe is high enough to cause significant band gap narrowing in low band gap HgCdTe. An enhanced Zener like band-to-band tunneling is proposed in the vicinity of dislocation cores. The calculations presented here qualitatively explain the observed influence of dislocations on HgCdTe photodiode characteristics.

Hodgkin (SPIE 6207(2006)) extended NVThermIP to be applicable to cold weather conditions. We also (IRPhys&Technol.51 (2008)520) later published an analysis of the effect of varying ambient temperature (Tamb) by modifying the inputs to NVTherm2002, and by using spectrally-weighted atmospheric transmission calculated from MODTRAN at different ambient temperatures and relative humidities (RH). We took into account the effects on the integration time and NETD, and we now account for the variation of uT with varying Tamb, as Hodgkin has done. The overall trends are similar, but we have NVTherm, not NVThermIP. We vary the parameters associated with Johnson's criteria to obtain similar results. Note that diurnal, seasonal, climatic and microclimatic variations of relative humidity (RH) significantly impact the performance of thermal imagers, especially LWIR ones. We compare the performance of thermal imagers a horizontal mean-sea-level path in clear weather conditions for terrestrial imagers and ground targets/scenes in both LWIR and MWIR bands, as a function of the ambient temperature from -40°C to +40°C and also as a function of RH (30%, 50% and 70%). To understand the differences in the results reported by Hodgkin and our paper, we do a sensitivity analysis as a function of system and environmental parameters (f/#, RH, detection probability, spectral width etc). For one set of parameters, we observe that the range curves RLW and RMW intersect at more than one value of Tamb and suggest an analogy to a 're-entrant phase'. We also analyze how motion blur affects the two bands, at different Tamb.

IR transmission curves of Hg1−xCdxTe(0.2

The premenstrual syndrome has been described briefly and the literature relating to its pathophysiology and treatment have been reviewed. The great number of theories as to etiology and many different kinds of treatments attest to our ignorance of the exact nature of this problem. Although it is obvious that the hypothalamo-pituitary-ovarian axis must be involved, the exact mechanism whereby the symptoms come about remains elusive. Progestin in the presence of estrogen appears to be essential. Excess estrogen may aggravate the condition. The popular theory of progesterone deficiency has not been supported by double blind trials of progesterone in various forms versus placebo. Because of the important placebo effect in this condition, double blind trials are essential in the assessment of any form of treatment.

We have characterized the mast cell stimulating activity of murine cytokine synthesis inhibitory factor, referred to as interleukin 10 (IL-10). It was found that IL-10 alone failed to support the growth of mast cell lines and mast cell progenitors. Nevertheless, it dramatically enhanced their growth when combined with IL-3 or IL-4. Moreover, IL-4 plus IL-10 supported the proliferation of mast cells as well as IL-3, suggesting that these two factors may provide a pathway for their development independent of IL-3. However, optimal mast cell growth was stimulated by the combination of IL-10, IL-4, and IL-3. This particular set of cytokines are coordinately produced by activated T cells and may constitute an effective network regulating early and late stages of mast cell development during certain immune responses.

Recently Siliquini and Faraone [J.F. Siliquini, L. Faraone, Infrared Phys. Technol. 38 (1997) 205] have proposed vertical photoconductive device (PC) based two-dimensional long wavelength infrared region focal plane arrays (LWIR FPAs). In this note, we examine some trade-offs and difficulties of this proposed structure.

Objective:To propose an alternative site of thyroid drain placement.Background:During thyroid surgery, post-operative drains are often placed. It is common practice to bring out the drain lateral to the wound, often creating an additional, unsightly scar.Conclusion:We have found excellent cosmesis is achieved by bringing out the drain in the midline in a sub-mental skin crease, with the scar hidden in the chin shadow. In our experience, such drain placement is a safe, straightforward method with an excellent cosmetic result.

Objectives:Airway fires pose a risk during laser microlaryngoscopy, and neurosurgical cotton patties, used to prevent tissue injury from stray laser beams, are a potential ignition source. Using a configuration approximating clinical practice, we experimentally assessed the relative impact of changing different ‘fire triad’ components on the occurrence of airway fires, in order to better inform patient care.Methods:The relative effects of wet vs dry neurosurgical patties, oxygen concentration and laser power setting on the patty ignition time were studied in a cadaveric porcine model. Data were analysed using t-test and two-way analysis of variance.Results:Dry patties ignited after 2.3 ± 1.2 seconds (average ± standard deviation) of continuous 5 W laser fire at 50 per cent oxygen concentration, compared with 63.9 ± 27.8 seconds for wet patties under the same laser and oxygen settings (p p Conclusion:We suggest that surgical patties should always be soaked and should be used for relatively short periods, in order to prevent drying. If at all possible clinically, prolonged laser use at high power settings and ventilation with 100 per cent oxygen should be avoided.

The authors report the first model of Zener tunnelling capacitance and its effect on the C-V characteristics of Hg1-xCdxTe. For narrow band Hg1-xCdxTe, with x=0.2, even at moderate doping densities, C-V curves exhibit low-frequency behaviour at measurement frequencies as high as 1 MHz (both for p-type and n-type MCT). The model predicts the reported trends in C-V characteristics as a function of composition, doping density and measurement frequency.

Recent evidence suggests that DNA sequences from the region lying 5' of the human epsilon-globin gene are important for erythroid-specific expression of human beta-like globin genes. This region, as well as a region 20 kilobases (kb) downstream from the beta-globin gene, contains a set of developmentally stable, DNase I-superhypersensitive sites that are thought to reflect a chromatin structure supporting active globin gene expression. We have analyzed the chromatin structure in these two regions in a wide variety of nonerythroid and erythroid cells. The study included analysis of chromatin structure changes occurring during globin gene activation in mouse erythroleukemia-human nonerythroid cell hybrids. The results identified a hypersensitive site (III) 14.8 kb upstream of the epsilon-globin gene that was strictly correlated with active globin gene transcription. Interestingly, a multipotent human embryonal carcinoma cell line exhibited a hypersensitive site (IV) 18.4 kb upstream of epsilon-globin that was absent in all other nonerythroid cells examined, suggesting that chromatin structure changes at specific hypersensitive sites during embryonic development may also be important in globin gene repression.

Eleven patients with moderate to severe premenstrual syndrome were given Premarin during the latter half of the menstrual cycle for at least two cycles, and a placebo for at least two cycles. Mental and physical symptoms were monitored daily with a self-rating scale. Premarin was significantly less effective than placebo in relieving the severity of both mental (p less than 0.02) and physical (p less than 0.02) symptoms of PMS (combined data p less than 0.01). It is concluded that luteal phase Premarin is ineffective as a treatment for PMS, and may actually aggravate the symptoms.

Uncommon events or out of the ordinary situations often trigger line yield losses such as misprocesses, miscommunications, or missed opportunities. D2 distributed bright red "Yield Risk" cards to the factory technicians to visually highlight material requiring special handling and tangibly draw attention to the unusual situation. The simplicity of the red cards coupled with the method used to proliferate the idea makes this system especially unique and transferable to other factories or situations where technician involvement is essential. This article documents and discusses results from the development and implementation of a visual tool, the Yield Risk card, used to enhance TMT yield effectiveness. The project was begun April 1, 1995, and continues today at D2 in response to high operations related line yield losses. The purpose of the project was to develop a tool that addressed line yield losses and received high levels of technician buy-in and, subsequently, high usage.