cssi/SciSciGPT-SciSciNet huggingface dataset:
Stability and robustness of large platoons of vehicles with double-integrator models and nearest neighbor interaction

SUMMARY We study the stability and robustness of a large platoon of vehicles, where each vehicle is modeled as a double integrator, for two decentralized control architectures: predecessor following and symmetric bidirectional. In the predecessor-following architecture, the control action on each agent only depends on the information from its immediate front neighbor, whereas in the symmetric bidirectional architecture, it depends equally on the information from both its immediate front neighbor and back neighbor. We prove asymptotic stability of the formation for a class of nonlinear controllers with sector nonlinearity, with the linear controller as a special case. We show that the convergence rate of the predecessor-following architecture is much faster than that of the symmetric bidirectional architecture. However, the predecessor-following architecture suffers high algebraic growth of initial errors. We also establish scaling laws (with N) of certain H ∞ norms of the formation that measure its robustness to external disturbances for the linear case. It is shown that the robustness performance grows geometrically in N for predecessor-following architecture but only polynomially in N for symmetric-bidirectional architecture. Extensive numerical simulations are conducted to verify the predictions for the linear case and empirically estimate the corresponding performance metrics for a saturation-type nonlinear controller. On the basis of the analytical and numerical results, it is seen that the symmetric bidirectional architecture outperforms the predecessor-following architecture in all measures of performance. Within the predecessor-following architecture, the nonlinear controller is seen to perform better in general than the linear one. A number of design guidelines are provided on the basis of these conclusions. Copyright © 2012 John Wiley & Sons, Ltd.
Reconstruction of 2-D signals from nonuniform samples in polar coordinates

The reconstruction of a bandlimited two-dimensional signal from a set of nonuniform samples is discussed. It is proved that Lagrange interpolation is possible in polar coordinates under a more general setup than that of H. Stark (J. Opt. Soc. Am., vol.69, p.1519-25, Nov. 1979), i.e. the nonuniform samples are on nonuniformly samples lie on radial lines and the rotational distances of radial lines are nonuniformly spaced. The nonuniform samples need not be limited to zeros of Bessel functions. >
Eczema Is Associated with Childhood Speech Disorder: A Retrospective Analysis from the National Survey of Children's Health and the National Health Interview Survey

Objective To determine if eczema is associated with an increased risk of a speech disorder. Study design We analyzed data on 354 416 children and adolescents from 19 US population-based cohorts: the 2003-2004 and 2007-2008 National Survey of Children's Health and 1997-2013 National Health Interview Survey, each prospective, questionnaire-based cohorts. Results In multivariate survey logistic regression models adjusting for sociodemographics and comorbid allergic disease, eczema was significantly associated with higher odds of speech disorder in 12 of 19 cohorts ( P P P = .03) and severe eczema (3.56 [1.70-7.48], P P = .003) and severe (2.28 [1.11-4.72], P = .03) speech disorder. Finally, significant interactions were found, such that children with both eczema and attention deficit disorder with or without hyperactivity or sleep disturbance had vastly increased risk of speech disorders than either by itself. Conclusions Pediatric eczema may be associated with increased risk of speech disorder. Further, prospective studies are needed to characterize the exact nature of this association.
SQ 20,881: Effect on eclamptic—pre-eclamptic women with postpartum hypertension

The renin-angiotensin system has been implicated in the genesis of pre-eclampsia. To avoid fetal toxicity, five women were studied who developed hypertension, proteinuria, and edema in the last trimester of pregnancy and whose BP elevation persisted immediately postpartum. At about 6 hours after delivery the CE enzyme inhibitor (SQ 20,881) was given in incremental doses ranging from 0.25 to 3.0 mg. per kilogram intravenously, before and after diuresis with furosemide, 40 mg. intravenously. BP was measure every 2 minutes and PRA and angiotensin II concentration before treatment, 30 minutes after 0.25 to 0.30 mg. per kilogram, and 30 minutes after 2.0 to 3.0 mg. per kilogram. Echocardiographic assessment of CI and PVR was performed before treatment and after a maximum dose in three patients. Before diuresis, CE blockade had no effect on heart rate, BP, CI, PVR, or PRA, regardless of whether the patient was in positive or negative fluid balance or was sodium loaded or restricted over the preceding 24 hours. Angiotensin II fell by 77 and 10 per cent, respectively, after 0.25 mg. per kilogram was given to two patients, but rose slightly in the other three patients, then fell an average of 46 per cent after 1.0 to 3.0 mg. per kilogram were given. After diuresis, 1.0 mg. per kilogram resulted in a 24 per cent fall in BP which persisted for 3 hours in two patients and a 14 per cent fall which lasted for 30 minutes after 1.0 or 3.0 mg. per kilogram in a third patient. It is concluded that the BP elevation which persists after delivery in certain patients with pre-eclampsia is not angiotensin II dependent.
Ramp tuning of the APS booster synchrotron magnet power supplies

The acceleration cycle of the Advanced Photon Source (APS) booster synchrotron is completed within 250 ms and is repeated at 2 Hz. The currents in the quadrupole and sextupole magnets must track the dipole current to within tight tolerances if the beam is to remain stable during acceleration. In order to meet the performance specifications, a monitoring system, online with the main control system, is used to measure machine performance and adapt power supply reference waveforms from cycle to cycle. The system optimizes the tracking between the power supplies, thus minimizing transient effects and taking care of any slow drifts. Tuning algorithms are described and their performance evaluated. Practical considerations are also discussed.
Penetration of human spermatozoa through the zona pellucida of nonviable human oocytes

OBJECTIVE The purpose of this study was to evaluate the penetrating capacity of human sperm through the intact zonae of nonviable human oocytes and the influence of oocyte storage conditions and gamete coincubation times on penetration rates. METHODS Immature oocytes were obtained from surgically removed ovarian tissue and from in vitro fertilization (IVF) and subjected to four storage conditions: 1) storage at 4 degrees C for up to 48 hours in culture medium (refrigeration, n = 53), 2) cryopreservation in 1.5 mol/L propanediol with storage at -196 degrees C (PrOH; n = 49), 3) cryopreservation in 2.0 mol/L dimethylsulfoxide with storage at -70 degrees C (DMSO; n = 20), and 4) storage in a hypertonic salt solution at 4 degrees C (salt; n = 30). Semen was obtained from fertile donors (n = 7) and after a wash and swim-up, samples were adjusted to 500,000 motile sperm/mL. Zonae and sperm were coincubated in 100-microL drops under oil, and penetration was assessed at 5 and 20 hours. Penetration was evidenced by visualization of at least one sperm head in the perivitelline space at 200x magnification. RESULTS Zona penetration rates were 50.9, 32.7, 23.3, and 10.0% for refrigeration, PrOH, salt, and DMSO storage, respectively (P < .004). There was a significantly higher number of sperm in the perivitelline space after 20 hours' coincubation (3.8 +/- 0.2) compared to 5 hours (0.8 +/- 0.1) (P < .0006). This represented an increase in the penetration rate from 31.2% (34 of 109) at 5 hours to 37.6% (41 of 109) at 20 hours, although the difference was not significant. CONCLUSIONS These results demonstrate that the zona pellucida of nonviable human oocytes can be used in a zona penetration assay and that refrigerated and PrOH-frozen intact zonae have the highest rates of penetration. The decrease in penetrability seen in DMSO and salt-stored oocytes may be due to alterations occurring in the zona pellucida.
Massless, half-integer-spon fields in de Sitter space

Gauge-invariant wave equations are obtained for massless fields in de Sitter space, with arbitrary, half-integer spin. Massless quanta with spins $s=\frac{1}{2}, \frac{3}{2}, \dots{}$ carry a series of unitary, irreducible representations of the de Sitter group. The special gauge fields carry another series of unitary, irreducible representations, hence ghost fields as well as the Goldstone and the associated special gauge field are actually massive in de Sitter space. Fields (properly: potentials) do not admit chirality for spins other than \textonehalf{}, but the field strengths associated with spin $\frac{3}{2}$ do admit duality.
Lattice Parameters of the α-Fe2O3-Cr2O3 Solid Solution

Lattice parameter-composition relations are shown in the system α-Fe2O3-Cr2O3. This information is of some value in determining the composition of scales developed during the oxidation of alloys based on Fe-Cr, such as stainless steels.
Impact of Design Cost on Project Performance of Design-Bid-Build Road Projects

AbstractThe vast majority of highway and street projects in the United States are procured and constructed by state or local governments using the design-bid-build (DBB) project delivery method. In the DBB method, the contractors build the project according to the detailed design and specifications prepared by the engineers. Using the DBB method, the quality of design has an impact on the construction performance. To date, only a few studies have measured the effect of design cost on the project performance of the road projects. In order to determine the impact of design cost on construction cost and schedule performance, this paper analyzes a sample of 47 Clark County public road projects of Nevada and 17 road projects of the Texas Department of Transportation (TxDOT). The sample includes projects completed between 1991 and 2009, and cost more than $3.43 billion in construction value, converted to a 2010 base cost. Besides determining the impact of design cost on the cost and schedule growth of the road ...
Idiopathic slipped capital femoral epiphysis in Amish children.

Background: Of the many studies of slipped capital femoral epiphysis, none have specifically addressed Amish children. The Amish reflect a small gene pool relative to the general white North American population. Additional knowledge of the demographics of this disorder in Amish children may provide genetic insights. The purpose of this study was to review the demographics of slipped capital femoral epiphysis in the Amish population. Methods: A retrospective review of the cases of twenty-five Amish children with slipped capital femoral epiphysis treated at two institutions was performed. The child's gender, age, weight, height, and body mass index at the time of the diagnosis; duration of symptoms; laterality of the slip; birth weight; family history; and slip severity were recorded. The slip was classified as stable or unstable. Patients who had been included in a previously published multicenter study served as a control group. Results: There were seventeen boys and eight girls with a total of thirty-three slipped capital femoral epiphyses; eight of the slips were bilateral. At the time of the diagnosis, the mean age (and standard deviation) was 13.4 ± 1.6 years, the mean weight and height were 55.6 ± 12.4 kg and 155.5 ± 10.2 cm, and the mean body mass index was 23.4 ± 5.4 kg/m2. The mean duration of symptoms was 6.6 ± 9.0 months. There were thirty-one stable and two unstable slips with a mean slip angle of 38° ± 20°. Nine (39%) of twenty-three children for whom the information had been recorded had a positive family history of slipped capital femoral epiphysis, a rate that is higher than the 9% and 14.5% rates reported in two other series (p = 0.002). The Amish children were not as heavy as their non-Amish counterparts (55.6 ± 12.4 kg compared with 66.4 ± 17.7 kg, p = 0.0036). Conclusions: Although the children in this study were moderately heavy, they could not be classified as obese on the basis of weight-for-age or body-mass-index percentiles. The high prevalence of family members with slipped capital femoral epiphysis may reflect either a genetic or environmental component, or an interaction between genetics and environment (for example, work load or common chores requiring particular physical positions) in the Amish population. Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.
First Results from the Six-Axis Electron Spectrometer on ISEE-1

A survey, using results from the first 25 orbits of ISEE-1, has been made of some aspects of electrons in the dawn magnetosheath. There are indications that the flow of plasma is not uniformly turbulent over this region. The electron heat flux is observed to be directed away from the shock and to have an average value of about twice the interplanetary heat flux. Many magnetopause crossings were observed and usually resemble abrupt transitions from one well-defined plasma state to another. The ejection of plasma from flux tubes convected up against the magnetopause is observed for about half the time, and its thickness and dependence on the solar wind mach number agree with theoretical predictions. A full traversal of the whole forward hemisphere of the magnetosheath is required to fully confirm these deductions.
A Penalized Neumann Control Approach for Solving an Optimal Dirichlet Control Problem for the Navier--Stokes Equations

We introduce a penalized Neumann boundary control approach for solving an optimal Dirichlet boundary control problem associated with the two- or three-dimensional steady-state Navier--Stokes equations. We prove the convergence of the solutions of the penalized Neumann control problem, the suboptimality of the limit, and the optimality of the limit under further restrictions on the data. We describe the numerical algorithm for solving the penalized Neumann control problem and report some numerical results.
Conformational dynamics of cytochrome c: correlation to hydrogen exchange.

We study the dynamical fluctuations of horse heart cytochrome c by molecular dynamics (MD) simulations in aqueous solution, at four temperatures: 300 K, 360 K, 430 K, and 550 K. Each simulation covers a production time of at least 1.5 nanoseconds (ns). The conformational dynamics of the system is analyzed in terms of collective motions that involve the whole protein, and local motions that involve the formation and breaking of intramolecular hydrogen bonds. The character of the MD trajectories can be described within the framework of rugged energy landscape dynamics. The MD trajectories sample multiple conformational minima, with basins in protein conformational space being sampled for a few hundred picoseconds. The trajectories of the system in configurational space can be described in terms of diffusion of a particle in real space with a waiting time distribution due to partial trapping in shallow minima. As a consequence of the hierarchical nature of the dynamics, the mean square displacement autocorrelation function, , exhibits a power law dependence on time, with an exponent of around 0.5 for times shorter than 100 ps, and an exponent of 1.75 for longer times. This power law behavior indicates that the system exhibits suppressed diffusion (sub-diffusion) in sampling of configurational space at time scales shorter than 100 ps, and enhanced (super-diffusion) at longer time scales. The multi-basin feature of the trajectories is present at all temperatures simulated. Structural changes associated with inter-basin displacements correspond to collective motions of the Omega loops and coiled regions and relative motions of the alpha-helices as rigid bodies. Similar motions may be involved in experimentally observed amide hydrogen exchange. However, some groups showing large correlated motions do not expose the amino hydrogens to the solvent. We show that large fluctuations are not necessarily correlated to hydrogen exchange. For example, regions of the proteins forming alpha helices and turns show significant fluctuations, but as rigid bodies, and the hydrogen bonds involved in the formation of these structures do not break in proportion to these fluctuations. Proteins 1999;36:175-191. Published 1999 Wiley-Liss, Inc.
Extensional flow of a two‐phase fiber

A steady, isothermal flow of a two-phase fiber spinning has been studied. To investigate the spinline velocity profile affected by the interaction between two fluids with different rheological properties, a Newtonian and an upper-convected Maxwell fluid were considered to be the core and skin layers, respectively. Unlike the one-dimensional analysis, which has been the typical approach for spinning flows, radial dependency of the flow field was maintained in our analysis. Consequently, a set of partial differential equations were derived for the flow field in the draw-down region where lubrication scalings are applicable. Asymptotic solutions were then obtained for two limiting cases, where the Deborah number of the skin layer is small and the applied axial tension is large. When the Deborah number of the skin layer is small, a velocity correction to the Newtonian profile indicates a strong effect of the flow rate ratio as well as the shear viscosity ratio of the two fluids. For the case of a large applied tension, which is more relevant to industrial practice, very interesting flow behaviors are predicted. In this limit, the viscoelasticity effect of the skin layer is shown to be dominant and dictates the mechanics of the flow even when both its flow rate and shear viscosity may be much smaller than those of the Newtonian core layer. The result also predicts that hoop stress has a negligible effect on the axial velocity profile.
Expert and Novice Performance in a Hypermedia Learning Environment for Classroom Observation Skills: The Impact of Prior Teaching Experience:

This study examined the process and outcomes of novice and expert teachers who learned a classroom observation coding system through a hypermedia learning environment. The training program was designed as a modular, skills-based approach following the stages of learning model. It allowed users nonlinear and user-controlled access to tutorials, guided practice, and multiple classroom situations for independent practice. Outcome measures included: 1) a coding test to assess knowledge of the behavioral codes and procedures, and 2) a reliability test to access proficiency with the code and routines under rigorous, timed conditions. It was found that novice teachers outperformed expert teachers in learning and using their observation skills. Implications focus on a discussion of the differences in observational experiences by novice and expert teachers which may form biases and the importance for hypermedia developers to consider the accuracy and adequacy of prior knowledge to help users assimilate new informa...
Photoluminescence of ZnO quantum dots produced by a sol gel process

Abstract We report synthesis and spectroscopic characterization of sol–gel derived zinc oxide (ZnO) quantum dots (Qdots) of 3–8 nm size. The Qdots exhibited a broad and strong visible emission peak centered near 520 nm with a quantum efficiency of approximately 5%. A weak ultraviolet (UV) emission peak was also observed near the band gap at 370 nm. The integrated area under the curve for the visible emission band was 35 times greater than that of the band-edge UV emission band of ZnO Qdots at room temperature. The photophysical characteristics (luminescence wavelength and intensity) of ethanol-dispersed Qdots were greatly affected over time (aging), suggesting the continuation of particle growth. In contrast, no such spectroscopic changes were noticed for air-dried ZnO Qdots. Time-resolved emission spectra of Qdots recorded at 520 nm emission were fitted with two sequential exponential decay curves with lifetimes of 14 ns and 77 ns. Visible photoluminescence of ZnO at low temperature (80 K) exhibited 150% higher intensity than that at room temperature. This was discussed based on the standard model of competitive radiative and non-radiative relaxation processes at various temperatures.
Abstract 246: Calmodulin binding to death receptor-5 regulates pancreatic cancer apoptosis

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Targeting the extrinsic apoptosis pathway initiated by death receptors has been shown to be a promising therapy for pancreatic cancer. TRA-8, a humanized activating antibody for the death receptor 5 (DR5), is a potent therapeutic reagent for pancreatic cancer. However, several pancreatic cell lines are resistant to TRA-8-induced cell death. We have previously demonstrated that calmodulin (CaM) is recruited into the death-inducing signaling complex (DISC) by Fas death receptor activation, and that antagonists of CaM regulate DISC formation. Therefore, we determined the function of CaM in DR5-induced apoptosis of pancreatic cancer cells. We found that trifluoperazine (TFP), a CaM antagonist, enhanced TRA-8-induced cell death of pancreatic cells, PANC-1 and S2VP10, by 55% and 45% respectively. Consistent with the increased apoptosis, TFP increased TRA-8-induced activation of caspase 8 and caspase 3 in these cells. To determine the underlying molecular mechanisms, we analyzed the DR5-induced DISC. Interaction of CaM and DR5 was demonstrated by co-immunoprecipitation by using DR5 antibody. Activation of DR-5 by TRA-8 increased recruitment of CaM into the DISC which was inhibited by treatment with TFP. In addition, TFP decreased recruitment of the adaptor protein, FADD, and recruitment of other DISC proteins that regulate cell survival, including Src and FLICE-like inhibitory protein (FLIP), an inhibitor of caspase-8. These results suggest an important role for CaM in DR5-induced DISC formation in pancreatic cancer cells, regulating DR5-mediated survival and apoptotic signaling. In summary, we have demonstrated that CaM antagonism sensitizes pancreatic cancer cell to TRA 8-induced cell death, and that CaM binding to DR5 regulates DR5-induced DISC formation. Defining the function of CaM in regulating DR5-induced signaling pathways may lead to novel therapeutic strategies for pancreatic cancer therapy including possible combination therapy with TRA-8 and calmodulin antagonists. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 246. doi:1538-7445.AM2012-246
Streptococcus pneumoniae-induced hemolytic uremic syndrome: a case for early diagnosis

Hemolytic uremic syndrome associated with infection by neuraminidase-producingStreptococcus pneumoniae usually presents with fulminant pneumonia and has a high mortality rate. Post-pneumococcal hemolytic uremic syndrome may occur earlier in life than classical hemolytic uremic syndrome. We describe an 18-month-old male with hemolytic uremic syndrome,S. pneumoniae pneumonia, and T-antigen activation characteristic of neuraminidase activity. We have summarized the features of this case and 11 previously reported children. As the use of blood products containing IgM may aggravate this disorder, early recognition of hemolytic uremic syndrome associated withS. pneumoniae neuraminidase production may lead to improved patient outcome through the judicious use of blood products.
Environment-induced changes in the base ratios of ribonucleic acid of Escherichia coli

Differences have been found in the base ratios of the total RNA of E. coli when it was grown on different media.
New Insecticides to Control Sunflower Moth

Three applications of endosulfan satisfactorily reduced damage to sunflower heads and seeds caused by Homoeosoma electellum (Hulst). Three other insecticides—methyl parathion, Gardona® (2-chloro-l-(2,4,5-trichloro-phenyl) vinyl dimethyl phosphate), and carbofuran adequately controlled this pest when applied at the onset of bloom and twice thereafter at intervals of 1 or 2 weeks. Triple applications of methyl parathion left residues on sunflower seeds which exceeded its established tolerance for this commodity.
Extended exposure to Sonic hedgehog is required for patterning the posterior digits of the vertebrate limb

Sonic hedgehog (Shh) is a key signal in establishing different digit fates along the anterior-posterior axis of the vertebrate limb bud. Although the anterior digits appear to be specified by differential concentrations of Shh in a traditional, morphogen-like response, recent studies have suggested that posterior digits are specified by an extended time of exposure to Shh rather than, or in addition to, a threshold concentration of Shh. This model for digit patterning depends upon continued Shh signaling in the posterior limb through mid-to-late bud stages. We find that cyclopamine, a potent antagonist of Shh signaling, can down-regulate hedgehog target genes in the posterior limb throughout the time Shh is expressed, indicating that continued active Shh signaling indeed takes place. To further explore the relative roles of time and concentration of Shh during limb development, we carried out two additional series of experiments. To test the effect of limiting the time, but not the amount of Shh produced, we treated chick embryos with the hedgehog antagonist cyclopamine at various stages of limb development. We find that short exposures to Shh result in specification of only the most anterior digits and that more posterior digits are specified sequentially with increasing times of uninterrupted Shh activity. To test the effect of limiting the level of Shh produced, but not the time of exposure, we genetically modified Shh production in mice. As previously shown, reducing both the concentration of Shh produced and the duration of Shh exposure results in a loss of posterior digits. We find that maintaining a low level of Shh production throughout the normal time frame of ZPA signaling results in a near complete restoration of the posterior-most digits. These data are consistent with, and lend additional support to, the model that concentration of Shh seen and duration of exposure both contribute to the dose-dependent specification of digit identities, but for the posterior-most digits the temporal component is the more critical parameter.
Ferriprotoporphyrin and its imidazole complex in aqueous-ethanolic solution.

Abstract 1. 1. In aqueous alkaline solution, 44% in ethanol, ferriprotoporphyrin is shown to be monomeric through study of the raction with CN − . 2. 2. In every alakaline aqueous solution (pH > 13) the coordination center of ferriprotoporphyrin is shown to dissociate a second proton. The process is not seen in 44% ethanol. 3. 3. In aqueous ethanolic solution, the constant for the equilibrium MIm 2 M − OH Im 2 H + = K′ f corresponding to the formation of the di-imidazole complex from ferriprotoporphyrin and imidazole is shown to be 1.0 · 10 14 1 3 · molde −3 at 25 °C. ΔH is −25 kcal/mol and ΔS ° is −20 cal · deg −1 · mole −1 . 4. 4. In every alkaline aqueous-ethanolic solution, the coordination center of the di-imidazole ferriprotoporphyrin complex is found to dissociate two protons. The dissociation constant for the two steps together is 1 · 10 −26 moles 2 · 1 −2 .
Blood serotonin in psychotic and brain damaged children

In this preliminary study blood scrotonin levels were measured in 11 severely disturbed children (9 boys and 2 girls) and 6 controls, matched for age, sex and verbal IQ. Tendency toward higher serotonin levels in patients was noted. However, the difference between patients and controls was not statistically significant. Low intellectual functioning was the only parameter which seemed to be clearly associated with higher serotonin levels.
Approaches to the control of multidrug-resistant (MDR) Acinetobacter baumannii

ISSUE: The emergence of MDR Acinetobacter baumannii in a metropolitan teaching hospital as an infection control (IC) problem beginning in 2000 and the efforts to reduce the incidence in our institution. PROJECT: In early March 2000, an increased incidence of MDR Acinetobacter baumannii in the surgical intensive care unit was noted in the process of focused surveillance in the unit. Retrospective microbiological culture results review indicated that this microorganism represented only 7 of 38 single patient clinical isolates (SPCI) (18%) in 1999. By the end of 2000, the incidence had doubled to 37% (28 of 75). Despite intensive infection control (IC) efforts to control the spread within the institution, the incidence rose in 2001 to 53 of 82 SPCI (65%) to represent the predominant strains within the strains cultured. Pulsed-field gel electrophoresis (PFGE) showed two endemic strains as well as confirming the importation of other strains in patients transferred to our institution from other hospitals. IC interventions included education of various disciplines of healthcare workers (including nursing, physicians, medical students, respiratory and radiology staff); and cultures of the environment (sinks in the patient rooms, computer keyboards, telephones, and supply cabinets). Each IC surveillance report included either the presence or absence of MDR Acinetobacter baumannii in the unit report. The IC medical director also reported the incidence biannually to the medical staff executive committee. These efforts continued through 2004. RESULTS: The incidence of MDR Acinetobacter baumannii showed a slight decrease in 2002 to 51% (45 of 89). In 2003, the incidence decreased further to 31% (22 of 72). In 2004, there was an increase to 46% (31 of 68), however 11 of the 31 (35.5%) were community-associated. LESSONS LEARNED: Continued vigilance for the presence of MDR Acinetobacter baumannii is necessary to control nosocomial transmission of this microorganism. Empiric initiation of contact precautions for patients with any Acinetobacter clinical isolate until susceptibilities are completed, emphasis on the importance of hand hygiene to prevent nosocomial transmission, and feedback of results both at the unit level as well as to the executive leadership is important to control this microorganism.
A prospective crossover study comparing secretin-stimulated endoscopic and Dreiling tube pancreatic function testing in patients evaluated for chronic pancreatitis

Background Direct pancreatic function tests (PFT) are conventionally performed with use of double-lumen "Dreiling" collection tubes. We have developed an endoscopic collection method (ePFT) that eases the performance of these tests. Objective Our aim was to compare the bicarbonate results obtained from the secretin ePFT and Dreiling PFT methods in patients evaluated for chronic pancreatitis. Design A prospective crossover design was used to compare the PFT methods. Setting Tertiary care referral center. Patients and Interventions Twenty-four patients undergoing an evaluation for chronic pancreatitis underwent the secretin-stimulated ePFT and Dreiling PFT methods on separate days. Main Outcome Measurements Duodenal fluid bicarbonate concentrations and estimated bicarbonate outputs were compared. Results The mean difference in peak bicarbonate concentration (Dreiling PFT minus ePFT) was 7 mEq/L (SD 20) and not statistically significant ( P = .11). A good correlation in peak bicarbonate concentrations ( r = 0.74, 95% CI, 0.48-0.88) and estimated bicarbonate output ( r = 0.78, 95% CI, 0.54-0.90) was observed between the two PFT methods. Limitation The sensitivities and specificities of the secretin ePFT and Dreiling PFT could not be compared because of the lack of a histologic gold standard. Conclusion The secretin ePFT yields results similar to those of the Dreiling PFT in patients evaluated for chronic pancreatitis.
Priests, Pollution and the Demonic: Evaluating Impurity in the Hebrew Bible in Light of Assyro-Babylonian Texts

The Priestly Source makes no explicit reference to the demonic when describing pollution which supposedly sets it apart from non-biblical conceptualizations of impurity. Most scholars explain the Priestly disregard for demons by referring to the advance of monotheism and the subsequent eradication of supernatural forces other than God. Depending on whether monotheism is viewed as gradual process or as the foundation of Israelite religion, commentators either detect a weakened demonic quality in Priestly pollution or claim that the Priestly Source has always been of a non-demonic nature. However, in recent years the idea that monotheism pervades most books of the Hebrew Bible has been increasingly called into question. At the same time, the extensive publication of Assyro-Babylonian ritual texts allows for better understanding of Assyro-Babylonian conceptualizations of impurity. These developments necessitate the reevaluation of the current views on Priestly pollution by examining Assyro-Babylonian texts pertaining to impurity and the demonic. Special attention is given to context and dating of the cuneiform sources used to exemplify the non-demonic nature of Priestly impurity. This renewed comparison of Priestly and Assyro-Babylonian impurity highlights how the Priestly writer frames the concepts of pollution within the context of the sanctuary and its maintenance. The Assyro-Babylonian texts dealing with impurity and demons, by contrast, focus on the individual and his/her relationship to the personal god rather than temple maintenance. Likewise, cuneiform texts that deal with pollution and temple maintenance do not concern themselves with demonic affliction. Consequently, it can be argued that the non-demonic nature of impurity in the Priestly Source is the result of the Priestly focus on the sanctuary and does not give witness to an underlying theological ideal.
The Role of Referent Indicators in Tests of Measurement Invariance

Confirmatory factor analytic tests of measurement invariance (MI) require a referent indicator (RI) for model identification. Although the assumption that the RI is perfectly invariant across groups is acknowledged as problematic, the literature provides relatively little guidance for researchers to identify the conditions under which the practice is appropriate. Using simulated data, this study examined the effects of RI selection on both scale- and item-level MI tests. Results indicated that while inappropriate RI selection has little effect on the accuracy of conclusions drawn from scale-level tests of metric invariance, poor RI choice can produce very misleading results for item-level tests. As a result, group comparisons under conditions of partial invariance are highly susceptible to problems associated with poor RI choice.
A posteriori estimation and adaptive control of the error in the quantity of interest. Part I: A posteriori estimation of the error in the von Mises stress and the stress intensity factor

In this paper we address the problem of a posteriori estimation of the error in an engineering quantity of interest which is computed from a finite element solution. As an example we consider the plane elasticity problem with the von Mises stress and the stress intensity factor, as the quantities of interest. The estimates of the error in the von Mises stress at a point are obtained by partitioning the error into two components with respect to the element which includes the point, the local and the pollution errors, and by constructing separate estimates for each component. The estimates of the error in the stress intensity factors are constructed by employing an extraction method. We demonstrate that our approach gives accurate estimates for rather coarse meshes and elements of various degrees. In Part II we will address the problem of the adaptive control of the error in the quantity of interest (the goal of the computation), and the construction of goal-adaptive meshes for one or multiple goals.
Pesticide transport in field soils

Abstract Pesticide contamination of water supplies has become a national issue. However, it is very challenging to quantitatively describe pesticide transport in field settings. The objective of this study was to quantify pesticide transport processes in field soils through modeling and field experiments. A transfer function model was modified to describe pesticide transport in the field. The model can be used to characterize the stochastic convective transport process with input chemical concentration changing with time, non-uniform soil water content distributions, adsorption, and degradation. A field experiment was conducted to assess the fate and mobility of two commonly used herbicides, dicamba and picloram. The herbicides were applied at two application rates to four plots (two replicates). The general transfer function was useful in fitting all the herbicide data within the different plots and depths, and was also utilized to predict herbicide concentration distributions with time and depth. The predicted results had reasonably good agreement with the field experimental data. For all comparisons, the predicted results matched the trend of the concentration distributions extremely well. By considering spatial and temporal variabilities, and other factors of the field soils, the modified transfer function proved to be a comprehensive and useful tool to model pesticide transport processes in field settings.
Semiconductor Infrared Optical Materials

Various semiconductors were evaluated for use as infrared optical materials. The materials evaluated include gallium arsenide, gallium phosphide, germanium, silicon, zinc sulfide and diamond. The method used to produce the materials is reviewed. Semi-insulating polycrystalline gallium arsenide was produced by a horizontal Bridgman process to sizes of 8 by 12 by 0.7 inches. Gallium phosphide was produced by a liquid encapsulated Czochralski technique to 2-inch diameter and 3-inch length. Germanium was obtained commercially from a casting technique. High-resistivity silicon having a 1-inch diameter and 6-inch length was obtained from a float-zone process. Zinc sulfide was obtained commercially from a chemical vapor deposition process. Polycrystalline diamond was obtained by a microwave chemical vapor deposition process. The optical, electrical, mechanical, and thermal properties of these materials are presented and compared. Thermal shock, rain erosion, and modulation transfer function analyses were performed, and the results for each material are presented and compared. It was found that all these materials have useful physical properties as infrared optical components in a wide range of applications.
Accounting for Out-of-Bandwidth Modes in the Assumed Modes Approach: Implications on Colocated Output Feedback Control

Colocated, output feedback is commonly used in the control of reverberant systems. More often than not, the system to be controlled displays high modal density at a moderate frequency, and thus the compliance of the out-of-bandwidth modes significantly influences the performance of the closed-loop system at low frequencies. In the assumed modes approach, the inclusion principle is used to demonstrate that the poles of the dynamic system converge from above when additional admissible functions are used to expand the solution. However, one can also interpret the convergence of the poles in terms of the zeros of the open-loop system. Since colocated inputs and outputs are known to have interlaced poles and zeros, the effect of modification to the structural impedance locally serves to couple the modes of the system through feedback. The poles of the modified system follow loci defined by the relative location of the open-loop poles and zeros. Thus, as the number of admissible functions used in the series expansion is increased, the interlaced zeros of the colocated plant tend toward the open-loop poles, causing the closed-loop poles to converge from above as predicted by the inclusion principle. The analysis and results presented in this work indicate that the cumulative compliance of the out-of-bandwidth modes and not the modes themselves is required to converge the zeros of the open-loop system and the poles of the closed-loop system.
Compactly-encoded optical flow fields for bidirectional prediction and video coding

We have previously developed an optical-flow-based motion estimator that produces dense, spatially-coherent motion fields under bit-rate constraints. These motion estimates target video coding applications, including post-processing applications in which no additional motion estimation step at the decoder is required. In frame-interpolation applications, significant improvements have been obtained over methods that rely upon the standard block-matching algorithm for motion estimation. We now extend these ideas to the case of video coders that use bidirectionally predicted B frames; the use of B frames provides temporal scalability and good compression performance. We develop a novel scheme to handle the problems caused by the presence of covered/uncovered regions. The scheme uses a label field to optimally weight the contributions of the forward and backward predictions. The label field is dense, with label values in the range (0, 1); we introduce a multiscale algorithm for jointly estimating and compressing the label field. In coding experiments on the Susie sequence, the use of label fields resulted in substantial visual and PSNR gains, especially in the fast moving parts of the sequence.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Endodermal sinus tumor of the mediastinum: A report of seven cases and review of the literature

Primary mediastinal endodermal sinus tumor is rare, and to date only 49 cases have been described in the English-language literature. Seven new cases are reported. Light microscopic examination showed characteristic features including papillary, reticular, tubular and solid growth patterns, complete or incomplete Schiller-Duval bodies and intracellular or extra cellular periodic acid-Schiff-positive material. Immunohistochemical studies showed alpha-1-antitrypsin in seven, alpha-fetoprotein in seven, keratin in six, and carcinoembryonic antigen in four cases. The beta summit of human chorionic gonadotropin, albumin, fibronectin, and transferrin were not found in any case. Electron microscopic studies performed in four cases showed intracellular and extracellular basement membrane-like material, multiple large multivesicular bodies, desmosomes and microvilli. Mediastinal endodermal sinus tumor can and must be differentiated from poorly differentiated adenocarcinoma metastatic or extending to the mediastinum because of the distinctly different prognoses and therapies. In spite of modern chemotherapy, the prognosis of mediastinal endodermal sinus tumor remains poor. The single most important prognostic indicator is whether the tumor mass can be completely excised before or after chemotherapy. Cancer 58:730-739, 1986.
A 200-245 GHz Balanced Frequency Doubler with Peak Output Power of +2 dBm

This paper presents a wideband 90 nm SiGe BiCMOS frequency multiplier at 200-245 GHz. The balanced multiplier results in a low first harmonic component, and uses a reflector at the base nodes to reflect the second harmonics to transistors for improved efficiency. The measured output power is > -2 dBm at 200-245 GHz with a peak value of +2 dBm at 224-228 GHz and a conversion gain of -15 dB. To the author's knowledge, this is the highest power wideband doubler at 200-250 GHz.
Polymorphous low-grade adenocarcinoma of minor salivary glands: a study of 17 cases with emphasis on cell differentiation.

Aims The diagnosis of polymorphous low-grade adenocarcinoma (PLGA) of salivary glands remains difficult for general surgical pathologists. In an effort to understand the morphological heterogeneity of these neoplasms and facilitate their recognition we reviewed the architectural patterns, cell differentiation and immunohistochemical features of 17 cases of PLGA. Methods and results There were 11 females and six males with a mean age of 58 years. Twelve tumours were located in the palate, two in the posterior third of the tongue, and one each in the upper lip, buccal mucosa and retromolar triangle. Two patients presented with neck metastases. The mean tumour size was 20 mm (range 6–50 mm). The tumour cells were arranged in five architectural patterns: tubules and small duct-like structures; cords and trabeculae; solid nests; cribriform areas and papillae. Twelve (71%) cases were composed of a combination of tubules and small duct-like structures, cords and trabeculae, and solid nests. Cribriform areas with pseudoluminal spaces were seen in six (35%) cases. A focal papillary pattern was evident in three cases and constituted 40% of the tumour in one. Perineural invasion was seen in 13 cases (76%). All cases studied were positive for CAM5.2, 34BE12, vimentin and S100 protein and showed overexpression of bcl-2 protein. Rb protein was present in 13 cases whereas p53 expression was absent in all cases. The average proliferation index (PI) was 7% (range 1–17%). Three patients developed local recurrences with cervical lymph node metastases but no patient died as result of tumour. No morphological features were found to be prognostic for the development of local recurrences or lymph nodes metastases. Conclusions PLGA is a distinctive neoplasm of salivary glands formed by luminal and nonluminal tumour cells with limited patterns of architectural differentiation. The relative proportion of these cells seems to play a significant role in the morphogenesis of these tumours. The overexpression of the bcl-2 protein and the low PI suggest that inhibition of programmed cell death may be involved in the oncogenesis of PLGA.
Abrupt reversal in ocean overturning during the Palaeocene/Eocene warm period

A global warming event that took place 55 million years ago at the end of the Palaeocene epoch is providing a picture of how Earth responds to climate change. The rapid rise in temperature was accompanied by turnovers in marine and terrestrial biota and changes in ocean chemistry and circulation. A study of carbon isotope records reveals a switch in the location of deep-water formation from the Southern Hemisphere to the Northern Hemisphere that was established within a few thousand years, but may have lasted for at least 40,000 years. This shows how greenhouse conditions can trigger quite rapid changes in deep ocean circulation that take much longer to be reversed. An exceptional analogue for the study of the causes and consequences of global warming occurs at the Palaeocene/Eocene Thermal Maximum, 55 million years ago. A rapid rise of global temperatures during this event accompanied turnovers in both marine1,2,3 and terrestrial biota4, as well as significant changes in ocean chemistry5,6 and circulation7,8. Here we present evidence for an abrupt shift in deep-ocean circulation using carbon isotope records from fourteen sites. These records indicate that deep-ocean circulation patterns changed from Southern Hemisphere overturning to Northern Hemisphere overturning at the start of the Palaeocene/Eocene Thermal Maximum. This shift in the location of deep-water formation persisted for at least 40,000 years, but eventually recovered to original circulation patterns. These results corroborate climate model inferences that a shift in deep-ocean circulation would deliver relatively warmer waters to the deep sea, thus producing further warming9. Greenhouse conditions can thus initiate abrupt deep-ocean circulation changes in less than a few thousand years, but may have lasting effects; in this case taking 100,000 years to revert to background conditions.