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Growing evidence suggests that maternal obesity may affect the intrauterine environment and increase a child's risk of developing asthma. We aim to investigate the relationship between prepregnancy obesity and childhood asthma risk.Cohorts of children enrolled in Kaiser Permanente Northern California integrated healthcare system were followed from birth (2005-2014) to age 4 (n = 104,467), 6 (n = 63,084), or 8 (n = 31,006) using electronic medical records. Child's asthma was defined using ICD codes and asthma-related prescription medication dispensing. Risk ratios (RR) and 95% confidence intervals (95% CIs) for child's asthma were estimated using Poisson regression with robust error variance for (1) prepregnancy BMI categories (underweight [18.5], normal [18.5-24.9], overweight [25-29.9], obese 1 [30-34.9], and obese 2/3 [≥35]) and (2) continuous prepregnancy BMI modeled using cubic splines with knots at BMI category boundaries. Models were adjusted for maternal age, education, race, asthma, allergies, smoking, gestational weight gain, child's birth year, parity, infant sex, gestational age, and child's BMI.Relative to normal BMI, RRs (95%CIs) for asthma at ages 4, 6, and 8 were 0.91 (0.75, 1.11), 0.95 (0.78, 1.16), and 0.97 (0.75, 1.27) for underweight, 1.06 (0.99, 1.14), 1.08 (1.01, 1.16), and 1.03 (0.94, 1.14) for overweight, 1.09 (1.00, 1.19), 1.12 (1.03, 1.23), 1.03 (0.91, 1.17) for obese 1, and 1.10 (0.99, 1.21), 1.13 (1.02, 1.25), 1.14 (0.99, 1.31) for obese 2/3. When continuous prepregnancy BMI was modeled with splines, child's asthma risk generally increased linearly with increasing prepregnancy BMI.Higher prepregnancy BMI is associated with modestly increased childhood asthma risk.

ObjectiveStudies suggest infants may be at increased risk of severe COVID-19 relative to older children, but few data exist regarding the incidence of COVID-19 episodes and associated risk factors. We estimate incidence rates and describe characteristics associated with medically attended COVID-19 episodes among infants younger than 6 months of age.MethodsWe analyzed electronic medical record data from a cohort of infants born March 1, 2020‒ February 28, 2021. Data from three health care delivery systems included demographic characteristics, maternal and infant outpatient visit and hospitalization diagnoses, and SARS-CoV-2 test results. Medically attended COVID-19 episodes were defined by positive SARS-CoV-2 clinical tests and/or COVID-19 diagnosis codes during medical care visits. Unadjusted and site-adjusted incidence rates by infant month of age, low and high SARS-CoV-2 circulation periods and maternal COVID-19 diagnosis were calculated.ResultsAmong 18,192 infants aged ConclusionMost medically attended COVID-19 episodes in infants aged Article SummaryThis report describes incidence rates and characteristics of medically attended outpatient and inpatient COVID-19 episodes among infants aged What’s Known on This SubjectSurveillance data and case series suggest that infants aged What this Study AddsAmong infants aged

The oscillation continuum in laser-induced fluorescence spectra of bound-free c

The oscillation continuum in laser-induced fluorescence spectra of bound-free $c^3\Sigma^+ \to a^3\Sigma^+$ and (4)$^1\Sigma^+ \to X^1\Sigma^+$ transitions of the KCs molecule were recorded by Fourier-transform spectrometer and modelled under the adiabatic approximation. The required interatomic potentials for ground $a^3\Sigma^+$ and $X^1\Sigma^+$ states were reconstructed in an analytical Chebishev-polynomial-expansion form in the framework of the regularization direct-potential-fit procedure based on the simultaneous consideration of experimental line positions from [R. Ferber et al, Phys. Rev. A, \textbf{80}, 062501 (2009)] and the present \emph{ab initio} calculation of short-range repulsive potential data. It was proved that the repulsive part over dissociation limit of the derived $a^3\Sigma^+$ potential reproduces the experiment better than the potentials reported in literature. It is also shown that all empirical and semi-empirical potentials available for the $X^1\Sigma^+$ state reproduce the bound-free (4)$^1\Sigma^+ \to X^1\Sigma^+$ spectrum with equal quality in the range of observations., Comment: 9 pages, 7 figures

Introduction Hip fractures are one of the most common traumatic injuries in the United States, secondary to an aging population. Multiple comorbidities are found in patients who present to trauma centers (TCs) with isolated hip fractures (IHFs) including significant cardiac disease. Aortic stenosis (AS) among these patients has been recently shown to increase mortality. However, factors leading to death from AS are unknown. We hypothesize that pulmonary hypertension (PH) is a significant mechanism of death among IHF patients with AS. Methods This is a multicenter retrospective cohort study examining IHF patients treated at Level I and II TCs within a large hospital system from 2015 to 2019. Patients who had IHFs and AS were compared to those who had IHFs, AS, and PH. Multivariable logistic regression was used to risk adjust by age, race, insurance status, and comorbidities. The primary outcome was inpatient mortality. The secondary outcomes were hospital-acquired complications. Results A total of 1388 IHF patients with AS were included in the study. Eleven percent of these patients also had PH. The crude mortality rate was higher if IHF patients had both AS and PH compared to IHF with AS alone (9% vs 3.7%, P-value .003). After risk adjustment, a higher risk of mortality was still significant (aOR 2.56 [95% CI 1.28, 5.11]). In addition, IHF patients with both AS and PH had higher complication rates; the exposure group had higher percentage of pulmonary embolism (1.4% vs .2%, adjusted P-value .03), new-onset congestive heart failure (4.1% vs 1%, adjusted P-value .01), and sepsis/septicemia (3.5% vs 1.4%, adjusted P-value .05). Conclusion In patients with IHFs, PH and AS increase the likelihood of inpatient mortality by 2.5 times compared to AS alone. Pulmonary hypertension among IHF patients with AS is an important risk factor to identify in the preoperative period. Early identification may lead to better perioperative management and counseling of patients at higher risk of complications.

Objectives Mucormycosis is a rare angioinvasive infection caused by filamentous fungi with a high lethality among the immunocompromised. In healthy people, the innate immune system is sufficient to prevent infection. The exception to this is deep tissue exposure seen during trauma. The purpose of this study is to evaluate the epidemiology of mucormycosis using a statewide population-based data set. Methods This is a retrospective cohort study of all hospital admissions for mucormycosis within the state of Florida from 1997 through the beginning of 2020. A distribution map was created to evaluate for geographic variation. Botanical growth zones, based on plant hardiness, used by state environmental agencies and landscapers were also used to detect possible patterns based on climate conditions throughout Florida. A multivariable regression analysis was performed to account for confounders and limit bias. Results A total of 1190 patients were identified for mucormycosis infection. Only 86 of these patients were admitted for trauma. Cutaneous infections were more prevalent among trauma patients while non-trauma patients had more pulmonary infections ( P = .04). Trauma patients with infection tended to be younger and less likely to suffer from comorbidities such as immunosuppression (36% vs 46%, P = .07) and diabetes (22.1% vs 47.1%, P ≤ .0001) as compared to their non-trauma counterparts. Mortality was similar with 17.8% for non-trauma patients and 15.1% for traumatized patients (AOR .80 [.42, 1.52]). Length of stay was longer for trauma patients (37.3 vs 23.0, P < .0001). Infections were less prominent in plant hardiness Zone 9 and Zone 10 as compared to Zone 8 (AOR .71 [.61, .82]; AOR .54 [.46, .64], respectively). Conclusion Trauma patients who develop infection from mucormycosis are at high risk of death despite being a younger and healthier population. Mucormycosis infections were primarily soft tissue based among trauma patients. These infections are more prevalent in colder regions within Florida.

This paper contains a proposal for a free, nonzero-rest-mass particle’s proper spacetime, determined exclusively by the particle’s rest mass $$m_0$$ m 0 and numbers. The approach defines proper time as de Broglie time, which is isomorphic to a sequence of natural numbers $$1, 2, \ldots , n$$ 1 , 2 , … , n that count de Broglie time units $$(h/c^2)(m_0^{-1})$$ ( h / c 2 ) ( m 0 - 1 ) (see Ferber in Found Phys Lett 9:575, 1996). The approach is based on defining the spatial coordinate as proper following the constructive definition of positive and negative integers as all possible differences of ordered pairs of natural numbers multiplied by the Compton unit $$(h/c)(m_0^{-1})$$ ( h / c ) ( m 0 - 1 ) . The spatial and temporal coordinates that form the particle’s proper spacetime are constructed as Euclidean projections of the de Broglie time. The corresponding expression in the form of an energy-momentum relation reveals the existence, aside from the rest energy term $$m_0c^2$$ m 0 c 2 , of an additional energy term of the same order of magnitude, which is related to large intervals of the $$m_0$$ m 0 -particle’s proper space. The relation of the numbers-based approach to the foundations of the special theory of relativity and of quantum mechanics is discussed.

The potential energy curves of the low-lying electronic states correlating up to the limit K(4p) + Rb(5s) of KRb molecule have been calculated using the multi-reference perturbation theory method at the CASSCF/ XMCQDPT2 level of theory without and with spin–orbit coupling. The calculated parameters of the ground X 1 R + state are in the best agreement among all previously performed ab initio calculations for the KRb molecule. The calculated vibrational intervals of the ground electronic term of the 39 K 85 Rb molecule describe the experiment with the accuracy within ±1 cm ?1 . The calculated intensities of the 2 1 R + (v 0 = 3, J 0 = 26) ? X 1 R + (v 00 = 0...24, J 00 = 25, 27) transitions satisfactory reflect the experimentally observed intensities distribution.

Summary 1. The sources of nitrogen for phytoplankton were determined for a bloom-prone lake as a means of assessing the hypothesis that cyanobacteria dominate in eutrophic lakes because of their ability to fix nitrogen when the nitrogen : phosphorous (N : P) supply ratio is low and nitrogen a limiting resource. 2. Nitrogen fixation rates, estimated through acetylene reduction with 15N calibration, were compared with 15N-tracer estimates of ammonium and nitrate uptake monthly during the ice-free season of 1999. In addition, the natural N stable isotope composition of phytoplankton, nitrate and ammonium were measured biweekly and the contribution of N2 to the phytoplankton signature estimated with a mixing model. 3. Although cyanobacteria made up 81–98% of phytoplankton biomass during summer and autumn, both assays suggested minimal N acquisition through fixation (

Atypical running gait biomechanics are considered a primary factor in the etiology of iliotibial band syndrome (ITBS). However, a general consensus on the underpinning kinematic differences between runners with and without ITBS is yet to be reached. This lack of consensus may be due in part to three issues: gender differences in gait mechanics, the preselection of discrete biomechanical variables, and/or relatively small sample sizes. Therefore, this study was designed to address two purposes: (a) examining differences in gait kinematics for male and female runners experiencing ITBS at the time of testing and (b) assessing differences in gait kinematics between healthy gender- and age-matched runners as compared with their ITBS counterparts using waveform analysis. Ninety-six runners participated in this study: 48 ITBS and 48 healthy runners. The results show that female ITBS runners exhibited significantly greater hip external rotation compared with male ITBS and female healthy runners. On the contrary, male ITBS runners exhibited significantly greater ankle internal rotation compared with healthy males. These results suggest that care should be taken to account for gender when investigating the biomechanical etiology of ITBS.

Glacial Lake Lind developed in the pre–late Wisconsinan St. Croix River valley, Minnesota and Wisconsin, and lasted more than 1000 yr during the retreat of the Superior lobe at the end of the Wisconsinan glaciation. Lake Lind sediment consists primarily of red varved silt and clay, but also includes mud-flow deposits, nearshore silt (penecontemporaneously deformed in places), nearshore rippled sand, and deltaic sand. Lake Lind varved red clay is not part of glacial Lake Grantsburg, as suggested by earlier authors, because the red varves are separated from overlying glacial Lake Grantsburg silt and clay by a unit of deltaic and fluvial sand. Furthermore, varve correlations indicate that the base of the red varves is younger to the north, showing that the basin expanded as the Superior lobe retreated and was not a lake basin dammed to the southwest by the advancing Grantsburg sublobe. Varve correlations indicate that the Superior lobe retreated at a rate of about 200 m/yr. Uniform winter-clay thickness throughout most of the varve couplets suggests thermal stratification in the lake with clay trapped in the epilimnion; some clay would exit the lake at the outlet prior to winter freeze. Zones of thicker winter-clay layers, in places associated with mud-flow layers, indicate outlet incision, lake-level fall, and shoreline erosion and resuspension of lake clay. The most likely outlet for glacial Lake Lind was in the southwest part of the lake near the present site of Minneapolis, Minnesota. Nearshore sediment indicates that the lake level of glacial Lake Lind was around 280 m. The elevation of the base of the Lake Lind sediments indicates water depth was 20 to 55 m. Evidence in the southern part of the lake basin suggests that the Superior lobe readvanced at least once during the early stages of glacial Lake Lind. Lake Lind ended not by drainage but by being filled in by prograding deltas and outwash plains composed of sand derived from the retreating Superior lobe. It was upon this fluvial surface that the Grantsburg sublobe advanced, depositing till and forming glacial Lake Grantsburg.

A comprehensive deperturbation analysis is made of the singlet—triplet D 1Δ ∼ d3Δ complex of the 23Na39K molecule. The deperturbation model takes into account direct spin—orbit coupling between the singlet and triplet states plus a spin—rotational interaction between different Ω components of the triplet state. The direct inversion procedure provides a self-consistent set of the Dunham molecular constants for both states and for the matrix elements of the spin—orbit interaction. The deperturbation analysis is supported by electronic structure calculations performed in the framework of the relativistic effective potential method combined with many-body multipartitioning perturbation theory. The theoretical spin—orbit matrix elements agree well with their experimental counterparts.

High resolution Fourier-transform spectroscopy data of term values in the spin-orbit (SO) coupled first excited A(1)Σ(+) and b(3)Π states in KCs were obtained from (4)(1)Σ(+) → A(1)Σ(+) - b(3)Π, A(1)Σ(+) - b(3)Π → X(1)Σ(+), and (1)(3)Δ1→b(3)Π(0(±)) spectra of laser-induced fluorescence (LIF). About 3000 new rovibronic term values of the A(1)Σ(+) and b(3)Π(Ω) states were obtained with an uncertainty about 0.01 cm(-1) and added to the previously obtained 3439 term values in Kruzins et al. [Phys. Rev. A 81, 042509 (2010)] and 30 term values of the b(3)Π(0(+)) state levels below the A(1)Σ(+) state in Tamanis et al. [Phys. Rev. A 82, 032506 (2010)]. The data field was extended considerably, going down to vibrational level v(b) = 0 and up in energy to 13,814 cm(-1), as compared to previously achieved v(b) = 14 and E = 13,250 cm(-1). Overall 6431 e-symmetry term values of (39)K(133)Cs were included in 4 × 4 coupled-channel deperturbation analysis. The analytical Morse-Long-Range (MLR) function yielded empirical diabatic potentials for the A(1)Σ(+) and b(3)Π(0(+)) states while the morphing of the SO ab initio points [J. T. Kim et al., J. Mol. Spectrosc. 256, 57 (2009)] provided the empirical diagonal and off-diagonal SO functions. Overall 98.5% of the fitted term values were reproduced with a rms (root mean square) uncertainty of 0.004 cm(-1). The reliability of the model is proved by a good agreement of predicted and measured term values of the (41)K(133)Cs isotopologue, as well as of measured and calculated intensities of (4)(1)Σ(+) → A(1)Σ(+) - b(3)Π LIF progressions. Direct-potential-fit of low-lying v(b) levels of the b(3)Π(0(-)) component yielded the MLR potential which represents the 204 f-symmetry experimental term values with a rms uncertainty of 0.002 cm(-1). The Ω-doubling of the b(3)Π0 sub-state demonstrates a pronounced vb-dependent increase.

The field array is the group of seismic sensors connected to a single recording channel. The impact of field arrays on the spatial bandwidth of the recorded seismic data is described by the array wavenumber amplitude transfer function. In this paper, I discuss, however the impact of the field array on the temporal bandwidth of the recorded data. A requirement for this is an accurate knowledge of the field array geometry. I also propose a novel technique to correct the corresponding signal amplitude distortions in data processing.

We introduce a novel technique for creating maps of bandwidth supported locally by non-uniform sampling schemes of geophysical data. The input data required are solely the coordinates of the actual sampling locations. The term “bandwidth supported locally by non-uniform sampling” refers here to the maximum bandwidth of data with a flat amplitude spectrum that could be reconstructed by an optimum “sinc-function” like linear operator at arbitrary sampling locations within the survey area without unacceptable high reconstruction error. Our technique creates individual maximum wavenumber estimators for selected locations, such that two-dimensional data can be reconstructed at non-sampling locations as long as the square root of the product of the two maximum spatial wavenumbers of the data is below the computed wavenumber estimator. For higher n-dimensional sampling, this extends to a wavenumber support estimator as the nth root of the product of the n maximum wavenumbers of the data. We outline how these maps can be computed from the local average of the size of cells designated to each sampling point, and give an example of a two-dimensional bandwidth support map for the midpoint locations of a part of a land seismic cross spread.

I adopt a concept of compressive sampling, namely the random demodulation of analog data before sampling, to the spatial acquisition of geophysical data. In summary, this translates into a simple modification of analog group forming, in which some sensors are randomly reversed in polarity, which can be achieved without adding any digital or analog devices to the individual sensors. I see potential applications wherever sensors are relatively inexpensive, but “channels”, i.e., analog-to-digital converters and other components, are relatively costly.

Objective To examine a reported association between use of angiotensin converting enzyme (ACE) inhibitors during the first trimester and risk of malformations in offspring. Design A population based, retrospective cohort study linking automated clinical and pharmacy databases including comprehensive electronic medical records. Participants Pregnant women and their live born offspring (465 754 mother-infant pairs) in the Kaiser Permanente Northern California region from 1995 to 2008. Main outcome measure Congenital malformation in live births. Results The prevalence of ACE inhibitor use in the first trimester only was 0.9/1000, and the use of other antihypertensive medications was 2.4/1000. After adjustment for maternal age, ethnicity, parity, and obesity, use of ACE inhibitors during the first trimester only seemed to be associated with increased risk of congenital heart defects in offspring compared with normal controls (those with neither hypertension nor use of any antihypertensives during pregnancy) (15/381 (3.9%) v 6232/400 021 (1.6%) cases, odds ratio 1.54 (95% confidence interval 0.90 to 2.62)). A similar association was observed for use of other antihypertensives (28/1090 (2.6%) cases of congenital heart defects, odds ratio 1.52 (1.04 to 2.21)). However, compared with hypertension controls (those with a diagnosis of hypertension but without use of antihypertensives) (708/29 735 (2.4%) cases of congenital heart defects), neither use of ACE inhibitors or of other antihypertensives in the first trimester was associated with increased congenital heart defects risk (odds ratios 1.14 (0.65 to 1.98) and1.12 (0.76 to 1.64) respectively). Conclusions Maternal use of ACE inhibitors in the first trimester has a risk profile similar to the use of other antihypertensives regarding malformations in live born offspring. The apparent increased risk of malformations associated with use of ACE inhibitors (and other antihypertensives) in the first trimester is likely due to the underlying hypertension rather than the medications.

In this paper, we present a new method for Q estimation in the presence of unreliable frequency ranges. Those unreliable frequencies can be caused by noise in distinct frequency ranges or destructive interference, for instance, from free-surface ghost reflections. We introduce the usage of noise-model or ghost-model-based weighting functions for spectral-division-based Q-estimation methods. The benefits of using noise or ghost models are demonstrated for a common-ray-parameter-based Q estimation on synthetic data. The proposed modifications are suitable for any frequency-based Q-estimation method.

Seismic interferometry refers to the study of interference of seismograms. The principal mathematical operation used to study this interference is the cross-correlation of pairs of seismograms, which can be understood as detecting the traveltime differenc

Modern seismic surveys accumulate large amounts of data due to the increased channel and shot counts (see Rached et al., 2006). Therefore we need to move away from the manual estimation of the first breaks, needed for the production of refraction based static corrections, and instead use more automatic methods. The novel technique described here is based on the theory of seismic interferometry to the estimation of rayparameter values as function of source and receiver offset. Seismic interferometry is the process of creating secondary seismic traces (interferograms) from pairs of genuine seismograms by cross-correlation (or spectral division). One major benefit of dealing with interferograms is that of estimating delay times by picking maxima of interferograms as opposed to picking first-break travel times from the actual seismograms. One application of the estimated rayparameter is to enhance automatic first break picking. The rayparameter is estimated in the region of the first breaks and is subsequently used in the stacking of adjacent traces. The stacked traces, with an improved signal-to-noise ratio, are analyzed in place of the original traces to provide better estimates of the first break times.

This paper discusses the construction of solid-state frequency multiplier chains utilized for terahertz receiver applications such as the Herschel Space Observatory. Emphasis is placed on the specific requirements to be met and challenges that were encountered. The availability of high power amplifiers at 100 GHz makes it possible to cascade frequency doublers and triplers with sufficient RF power to pump heterodyne receivers at THz frequencies. The environmental and mechanical constraints are addressed as well as reliability issues.

Mature hydrocarbon provinces are increasingly being re-explored to extend the productive lives of existing fields by testing outlier or deeper objectives for additional reserves. In recent years the introduction of affordable 3-D pre-stack depth migration (PSDM) has allowed very complex geology to be properly imaged to more fully assess hydrocarbon potential in many of these mature areas. This paper discusses a 3-D seismic depth reprocessing program undertaken in a complex U.S. Overthrust area to assess the validity of a deep structure (approx. 5500m) identified on 3-D time-processed data in this mature prolific gas producing province. The 1998 vintage seismic 3-D acquisition method did not allow a seismically derived velocity model capable of accurately representing the subsurface to be defined in this older/fast rock regime. A 3-D pre-stack depth migration velocity model-building solution is presented that overcame the limited sensitivity to velocity of these 1998 3-D seismic data. By collaborating with client geologic expertise to integrate key geologic insights into the 3-D velocity model-building process and tightly constraining the seismically derived velocity with available well control, a subsurface velocity depth model was obtained that provided an accurate depth image of the deep target zone in this geologically complex area.

Various definitions of arousals have been used in infants. An international group of experts has worked on a consensus for the scoring of arousals in healthy infants, aged between 1 and 6 months. This opinion paper summarizes the consensus statement on the scoring of arousal. The paper reviews recommended techniques for the recording of arousal in infants. Scoring includes the differentiation between subcortical activation, with no visible change n the electroencephalograph (EEG) recording, and cortical arousals associated with EEG changes. The arousals are further scored as spontaneous or induced, according to environmental conditions. Potential limitations to the method are discussed, with the hope that this document could contribute to promote further progresses in the scoring of infants arousals from sleep.

Publication in the conference proceedings of EUSIPCO, Antalya, Turkey, 2005

A22 MULTI-DIMENSIONAL FILTERING OF SEISMIC DATA SAMPLED ON AN IRREGULAR GRID Abstract 1 In this paper we introduce a new technique for multi-dimensional filtering of irregularly sampled seismic data. In this context filtering may be used for coherent noise and interference attenuation as well as the generation of seismic images. The filtering operation consists of the convolution of the filter operator with the seismic data. The filter operator is usually computed on a regular grid (rectangular or hexagonal) that corresponds to the nominal sampling of the seismic data. Unfortunately in the physical world the seismic data are often sampled at

Objective To examine a reported association between use of angiotensin converting enzyme (ACE) inhibitors during the first trimester and risk of malformations in offspring. Design A population based, retrospective cohort study linking automated clinical and pharmacy databases including comprehensive electronic medical records. Participants Pregnant women and their live born offspring (465 754 mother-infant pairs) in the Kaiser Permanente Northern California region from 1995 to 2008. Main outcome measure Congenital malformation in live births. Results The prevalence of ACE inhibitor use in the first trimester only was 0.9/1000, and the use of other antihypertensive medications was 2.4/1000. After adjustment for maternal age, ethnicity, parity, and obesity, use of ACE inhibitors during the first trimester only seemed to be associated with increased risk of congenital heart defects in offspring compared with normal controls (those with neither hypertension nor use of any antihypertensives during pregnancy) (15/381 (3.9%) v 6232/400 021 (1.6%) cases, odds ratio 1.54 (95% confidence interval 0.90 to 2.62)). A similar association was observed for use of other antihypertensives (28/1090 (2.6%) cases of congenital heart defects, odds ratio 1.52 (1.04 to 2.21)). However, compared with hypertension controls (those with a diagnosis of hypertension but without use of antihypertensives) (708/29 735 (2.4%) cases of congenital heart defects), neither use of ACE inhibitors or of other antihypertensives in the first trimester was associated with increased congenital heart defects risk (odds ratios 1.14 (0.65 to 1.98) and1.12 (0.76 to 1.64) respectively). Conclusions Maternal use of ACE inhibitors in the first trimester has a risk profile similar to the use of other antihypertensives regarding malformations in live born offspring. The apparent increased risk of malformations associated with use of ACE inhibitors (and other antihypertensives) in the first trimester is likely due to the underlying hypertension rather than the medications.

Lung transplantation from a donor with chronic renal failure has never been reported. This paper reports our successful experience with 2 transplants from donors with end-stage renal disease who were on chronic hemodialysis, and reviews the relevant literature on the effects of renal failure on pulmonary function and on the use of marginal donors.

The cross-spread is the basic subset of the orthogonal geometry. It is a single-fold 3D data set which was shown by Vermeer et al. (1995) to be suitable for DMO. This was good news, because DMO was usually regarded as an operation on common-offset common-azimuth (COA) subsets of the acquisition geometry.

A major product of 3-D seismic data processing is the time migrated data cube. With conventional processing, this cube is generated by poststack time migration of the zero-offset cube, obtained by NMO-DMO stacking of multi-offset data. A major drawback of this processing sequence is, that migrated data can only be inspected at a very late stage of data processing and that there is no simple and efficient technique to derive the migration velocity field. In this presentation we show results of a recently developed 3-D prestack time migration technique to overcome this deficiency. Our method allows the generation of time migrated bin-gathers on a coarse grid within the 3-D survey, without a priori knowledge of a migration velocity field. These gathers hold an offset axis and a two-way travel-time axis, where the time is measured along the image ray. The migration velocities can then be estimated from the generated migrated data by conventional means, e.g. from semblance velocity spectra and multi velocityfunction stacks. The stack of the migrated data generates the proposed quick-look of the 3-D time migrated data set on the coarse grid. The estimated migration velocities are an additional product of this technique. They can be used to replace the smoothed dip-corrected stacking velocity field for the poststack migration of the zero-offset cube on the final grid.

Irregular acquisition geometry is inevitable due to obstacles and cable feathering in 3-D marine surveys and access limitations in 3-D land surveys. The irregularities will damage the fidelity of seismic images, unless they are properly handled in the processing. DMO in particular, must take account of the actual geometry. Black, Schleicher, and Zhang (1993) have developed an anaiytical calibration method that is implemented via the DMO amplitude term. In this paper we extend the DMO calibration to take into account the irregular geometry, and develop a geometrical calibration.

The objective assessment of patients with a presumptive diagnosis of obstructive sleep apnea (OSA) has primarily used attended polysomnographic study. Recent technologic advances and issues of availability, convenience and cost have led to a rapid increase in the use of portable recording devices. However, limited scientific information has been published regarding the evaluation of the efficacy, accuracy, validity, utility, cost effectiveness and limitations of this portable equipment. Attaining a clear assessment of the role of portable devices is complicated by the multiplicity of recording systems and the variability of clinical settings in which they have been analyzed. This paper reviews the current knowledge base regarding portable recording in the assessment of OSA, including technical considerations, validation studies, potential advantages and disadvantages, issues of safety, current clinical usage and areas most in need of further study.

Schedule-dependent sleep problems tend to increase as the youngster moves from middle childhood through preadolescence and into adolescence. This is partly because the youngster becomes more independent and parental control over both the selection of particular sleep schedules and the consistent maintenance of these schedules across weekends diminishes. Even accurate descriptions of the existing problem may become difficult to obtain. Nevertheless, specific syndromes are common and may be identified and treated. There may be increased demands at both ends of the sleep period leading to later bedtimes, earlier wakings, insufficient sleep, and daytime sleepiness. Periods of wakefulness confined to one portion of the night (beginning, middle, or end) may occur if sleep requirements are overestimated. Insomnia coupled with trouble waking may imply a circadian phase shift abnormality or a 'school-refusal' variant. And, variable sleep difficulties may be seen in a youngster with irregular schedules and poor sleep hygiene. Guidelines to the understanding, evaluation, and treatment of these syndromes are presented.

In two experiments we explore the relationship of gaze control to quiet stance and lunge in elite ballet dancers, ACL-deficient and normal controls. In order to maintain postural stability, all direct their gaze straight ahead at appropriate moments in order to maintain alignment of the centre of gravity over the functional centre of pressure (CoP). Not surprisingly, the elite ballet dancers were better at establishing a line of gaze forward at appropriate moments while the other groups were less likely to use this gaze control strategy. The ballet dancers appeared to use a visual straight ahead (VSA), which was a line of gaze horizontal to the base of support that momentarily stabilized their body for current and future actions. Surprisingly, they employed a more variable CoP, while the normal controls and ACL-deficient adopted a CoP distributed over a narrower and less dynamic base of support even while the gaze tracked a more variable pattern in space. In the lunge forward to return, the results were similar, with the exception the ballet dancers were more adept at returning their gaze to the VSA at appropriate moments while the ACL deficient had greater difficulty. These results are discussed within Bernstein’s notion of “freezing, freeing, and exploiting” the degrees of freedom of an action, in terms of both the control of the gaze and posture.

Markets, applications, and production techniques for Siemens process-produced polycrystalline silicon are surveyed. It is noted that as of 1982 a total of six Si materials suppliers were servicing a worldwide total of over 1000 manufacturers of Si-based devices. Besides solar cells, the Si wafers are employed for thyristors, rectifiers, bipolar power transistors, and discrete components for control systems. An estimated 3890 metric tons of semiconductor-grade polycrystalline Si will be used in 1982, and 6200 metric tons by 1985. Although the amount is expected to nearly triple between 1982-89, research is being carried out on the formation of thin films and ribbons for solar cells, thereby eliminating the waste produced in slicing Czolchralski-grown crystals. The free-world Si production in 1982 is estimated to be 3050 metric tons. Various new technologies for the formation of polycrystalline Si at lower costs and with less waste are considered. New entries into the industrial Si formation field are projected to produce a 2000 metric ton excess by 1988.

Large-area silicon sheet technology is being developed under the U.S. Department of Energy's National Photovoltaics Program to realize high-efficiency, low-cost photovoltaic (PV) cells that are the building blocks of PV modules and arrays. Both ingot technology and ribbon technology sheet-growth approaches are being pursued. The ingot technology includes Czochralski (Cz) growth and casting processes. Large ingots, both cylindrical and square, have been grown to demonstrate feasibility of producing satisfactory ingots for fabricating PV cells. These developments have been largely adopted by industry and Program-sponsored activities have been reduced. Wafering technology is also being developed, using both rotating-blade and linear-motion saws. Wafering appears to have reached a point where additional fundamental understanding of the sawing mechanism is needed to further wafering technology. Empirical developments have been concluded and only limited fundamental studies, which relate to fracture behavior, c...

Although the subject of shielding by means of ferromagnetic materials has been investigated for almost four centuries, 1 it is not as well understood as the subject of shielding by means of nonferromagnetic materials. Many publications have dealt with magnetic shielding in both steady and time varying situations. Most of these papers are concerned with the calculations of shielding effectiveness for various configurations. To facilitate the computations, the permeability of the material is usually assumed to be a constant because without the aid of powerful digital computers the calculations would be impossible. In many cases the permeability chosen to represent the material is adjusted to make the calculations agree with experiment. Hence, in the past nearly all magnetic shielding problems have been treated as nonmagnetic shielding problems with the material permeability chosen greater than unity.