cssi/SciSciGPT-SciSciNet huggingface dataset:
Pigment-associated proteins of Xanthomonas campestris pv. juglandis

Two pigment-protein complexes extracted from the cell membrane of Xanthomonas campestris pv. juglandis with 2% Triton X-100 were separated from other membrane proteins by electrophoresis on a 10%., non-denaturing discontinuous polyacrylamide gel. One pigment-protein complex band was distinct, while the other was diffuse. The apparent Mr of the protein from the distinct pigment-protein band was 16400, while the protein in the diffuse band had an apparent Mr of about 45000. The protein in the distinct band consisted of 13 amino acids of which 10% were aromatic, 12% hydroxy, 16% basic, 16% acidic and 46% non-polar. Polyclonal antibody, against the distinct protein, was used to assay for cross-reactivity with cell wall and membrane proteins of 23 bacterial species by the Ouchterlony double-diffusion assay. Seven of the bacteria, representing seven genera, cross-reacted with the antibody, suggesting that a serologically-related, pigment-associated protein is commonly distributed among bacteria and which, unlike the pigment, may limit its use as a chemotaxonomic marker for Xanthomonas.
A COMPARATIVE STUDY OF TISSUE CARBON DIOXIDE IN VERTEBRATES.

Abstract 1. 1. A comparative study of the normal values of arterial blood pH, plasma CO2, plasma pCO2, total skeletal muscle CO2 and barium-soluble CO2 was made in the rat, pigeon, turtle, frog and catfish. 2. 2. Arterial blood pH was not significantly different among the species, the mean values ranging from 7·42 to 7·55. 3. 3. Plasma CO2 varied widely, the lowest mean value, 7·1 mM/1, being in the catfish and the highest, 34·9 mM/1, being in the turtle. 4. 4. pCO2, of the plasma was around 40 mm Hg in the three land vertebrates, 19·7 mm in the frog and 9·2 mm in the catfish. 5. 5. Total muscle CO2 ranged from 3·0 mM/kg in the catfish to 16·0 mM/kg in the turtle. 6. 6. Barium-soluble muscle CO2 was present in all species and increased with increasing total muscle CO2 in a manner comparable to that expected in mammals at the pCO2, involved, except possibly in the turtle, in which the fraction was low. 7. 7. Pigeon breast muscle contained a significantly higher concentration of CO2 than did high muscle, the ratio being 1·33 ± 0·051 (S.E.). 8. 8. Muscle CO2 concentrations varied directlu with pCO2; however, capacities appeared comparable in the species investigated.
Cell migration by graded attachment to substrates and contraction

The migration of fibroblastic cells in vitro involves the extension of lamellipodia, attachment of the cytoskeleton through the plasma membrane to the extracellular matrix, and the generation of force that pulls attachments rearward and the cell forward. Bulk flow of membrane or lipid relative to the cell outline cannot be detected; however, crosslinked glycoproteins attached to the cytoskeleton move rearward and diffusing particles are driven forward by a motor mechanism. The leading edge is the preferential site for the cytoskeleton to attach to crosslinked glycoproteins including integrins. Force for moving the cell forward can be generated either by a cortical contraction acting as a net to pull the endoplasm forward or by motors at the boundary of the endoplasm and ectoplasm pulling on the cortical actin. As the cortical actin is anchored to the external matrix more strongly at the front of the cell than at the rear, contraction will pull the cell forward. Such a model has important implications for the nature of the glycoprotein attachments to the cytoskeleton and the regional differences in membrane structure.
On the eigenvalue problem for fluid sloshing in a half-space

The boundary-value problem for free oscillations of a liquid in a half-space, which is bounded above by a rigid plane that contains a circular aperture, is transformed to a homogeneous, Fredholm integral equation for the velocity distribution in the aperture. Rayleigh-Ritz approximations to the eigenvalues are obtained by expanding the velocity distribution in appropriately weighted Jacobi polynomials. Numerical results demonstrate that the convergence of the approximations is much stronger than that of the approximations developed by Henrici, Troesch and Wuytack; for example, retaining twelve terms in the Rayleigh-Ritz expansion yields the dominant eigenvalue within one part in 10−8. A corresponding development is given for the two-dimensional problem, in which the aperture is an infinite strip.
Functional characterization of exopolyphosphatase/guanosine pentaphosphate phosphohydrolase (PPX/GPPA) of Campylobacter jejuni

The inorganic polyphosphate (poly-P) is a key regulator of stress responses and virulence in many bacterial pathogens including Campylobacter jejuni. The role of exopolyphosphatases/guanosine pentaphosphate (pppGpp) phosphohydrolases (PPX/GPPA) in poly-P homeostasis and C. jejuni pathobiology remains unexplored. Here, we analyzed deletion mutants (∆ppx1, ∆ppx2) and the double knockout mutant (dkppx), all ∆ppx mutants exhibited increased capacity to accumulate poly-P; however only ∆ppx1 and dkppx mutants showed decreased accumulation of ppGpp, an alarmone molecule that regulates stringent response in bacteria, suggesting potential dual role for PPX1/GPPA. Nutrient survival defect of ∆ppx mutants was rescued by the supplementation of specific amino acids implying that survival defect may be associated with decreased ppGpp and/ or increased poly-P in ∆ppx mutants. The ppk1 and spoT were upregulated in both ∆ppx1 and ∆ppx2 suggesting a compensatory role for SpoT and Ppk1 in poly-P and ppGpp homeostasis. The l...
Equilibrium between uptake and elimination of dieldrin by channel catfish, Ictalurus punctatus.

Channel catfish,Ictalurus punctatus, measuring 150 (±5) mm were exposed continuously to dieldrin for 70 days to determine if equilibrium between dieldrin uptake and elimination was reached by muscle tissue. Fish exposed to 13 parts per trillion (pptr) dieldrin reached equilibrium in 56 days, fish exposed to 27 pptr dieldrin were near equilibrium after 56 days, and fish exposed to 49 pptr dieldrin did not reach a balance between uptake and elimination after 70 days of exposure. Evidence of this study showed that balance between uptake and elimination was reached in less time at lower exposure levels than at higher levels.
Letter to the Editor: The C-terminal Domain of Viral IAP Associated Factor (cVIAF) is a Structural Homologue of Phosducin: Resonance Assignments and Secondary Structure of the C-Terminal Domain of VIAF

Jaison Jacoba,∗, John M. Louisb, B. W. M. Richterc,∗∗, Colin S. Duckettc & Dennis A. Torchiaa aMolecular Structural Biology Unit, National Institute of Dental and Craniofacial Research and bLaboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, U.S.A.; cDepartments of Pathology and Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109, U.S.A.
Comment on ''Assessing the implications of K isotope cosmochemistry for evaporation in the preplanetary solar nebula'' by E. Young

Young [1] has presented an ablative^diiusive model to reinterpret the K isotopic data of Humayun and Clayton [2], arriving at signi¢cantly diierent conclusions. Here, I show that Young's model [1] fails to explain the ubiquitous presence of volatile element depletion, and that his interpretations of the K isotopic data of [2] are achieved by replacing an intensive variable used by [2] with an extensive variable developed by [1] that traces mass loss but not volatile element depletion. Further discrepancies introduced by [1] also in£uence the outcome. It is shown here that the ablative^diiusive model of Young [1] has no cosmochemical applications. The intellectual foundations of K isotope cosmochemistry rest upon decades of work (summarized by [2^4]) by E. Anders, S.R. Taylor, H. Wa«nke, H. Palme, and others that showed that the chemical compositions of Earth, Moon and meteorites exhibit distinct volatile element depletion relative to Si, and refractory elements, when compared with CI chondrite compositions. These eiects are characterized by an increasing order of depletion with decreasing condensation temperature, such that the order of depletion in the Earth is La6 Si6K6Rb6Cs6Pb [3,4], and were recognized to be caused by processes such as partial evaporation or incomplete condensation, which had operated selectively on the basis of condensation temperature. Young [1] proposes an inherently non-selective process: evaporation so intense that both volatile elements and major elements are lost su¤ciently rapidly to constitute an ablative process, in which evaporative losses are restricted to a diiusively limited boundary layer on the exterior of the body experiencing the intense thermal event. The chemical composition of the body inwards of the boundary layer is identical to its initial chemical composition prior to the thermal event. However, the ablative nature of the process drives the boundary layer inwards at a rate, dr/dt, which (if not arrested by termination of the heating event) would eventually consume the entire object. The model developed by Young [1] has a characteristic non-dimensional number, the `ablative^ diiusive Peclet number' :
The effects of the structure of sterols on the development of Heliothis zea

Abstract Heliothis zea was reared on artificial diets which lacked supplementation with plant materials but were supplemented with different sterols in order to determine how certain structural features of a sterol molecule affect the development of this insect. We found that sitosterol and cholesterol supported a more rapid rate of growth than did campesterol. Larvae did not moult when they ingested 5-pregnen-3β-ol. Larvae utilized spinasterol more efficiently than lathosterol. Such a pronounced effect was not observed in the Δ 5 -series. The substitution of a Δ 7 -bond (spinasterol, dihydrospinasterol, lathosterol) for the Δ 5 -bond (stigmasterol, sitosterol, cholesterol) in the 24-ethyl- and desalkylsterols reduced the rate of growth of the larvae. Although larvae developed normally on cholesterol, the addition of a Δ 7 -bond to give the Δ 5,7 -diene system apparently altered the functionality of the molecule because 7-dehydrocholesterol did not support larval development. The growth of larvae was also inhibited, although not prevented, when they consumed diets which contained ergosterol. In contrast, the larvae completed their development more rapidly on brassicasterol which lacked the Δ 7 -bond. Cholestanol supported the complete development of the insect. H. zea is unusual among investigated insects because it develops both on cholestanol and lathosterol but does not utilize ergosterol efficiently and fails to grow on 7-dehydrocholesterol.
Friction and wear behavior of poly(vinyl alcohol)/poly(vinyl pyrrolidone) hydrogels for articular cartilage replacement

Many hydrogels have been proposed as articular cartilage replacements as an alternative to partial or total joint replacements. In the current study, poly(vinyl alcohol)/poly(vinyl pyrrolidone) (PVA/PVP) hydrogels were investigated as potential cartilage replacements by investigating their in vitro wear and friction characteristics in a pin-on-disk setup. A three-factor variable-level experiment was designed to study the wear and friction characteristics of PVA/PVP hydrogels. The three different factors studied were (a) polymer content of PVA/PVP hydrogels, (b) load, and (c) effect of lubricant. Twelve tests were conducted, with each lasting 100,000 cycles against Co-Cr pins. The average coefficient of friction for synovial fluid lubrication was a low 0.035 compared with 0.1 for bovine serum lubrication. Frictional behavior of PVA/PVP hydrogels did not follow Amonton's law of friction. Wear of the hydrogels was quantified by measuring their dry masses before and after the tests. Higher polymer content significantly reduced the wear of hydrogel samples with 15% PVA/PVP samples, showing an average dry polymer loss of 4.74% compared with 6.05% for 10% PVA/PVP samples. A trend change was observed in both the friction and wear characteristics of PVA/PVP hydrogels at 125 N load, suggesting a transition in the lubricating mechanism at the pin-hydrogel interface at the critical 125 N load.
Women's positive perception of transvaginal NOTES surgery

Two decades ago, minimally invasive surgery (MIS) was introduced and led to a revolution in modern surgery. Currently MIS procedures are the standard of care for many surgical interventions and patients often seek out surgeons with special training in MIS. Today, natural orifice transluminal endoscopic surgery (NOTES) appears to be on the threshold of another such revolution. We surmise that its advantages are similar to those of other MIS procedures, but there are no associated abdominal wall complications as there are no abdominal incisions. To date, there is no data evaluating women’s perceptions of such a procedure and their willingness to consent to this type of surgical approach. We surveyed 100 women who were given a written description of MIS and NOTES surgery along with a 10-question survey exploring their concerns and opinions regarding transvaginal surgery. The majority of women (68%) indicated that they would want a transvaginal procedure in the future because of decreased risk of hernia and decreased operative pain (90 and 93%, respectively), while only 39% were concerned with the improved cosmesis of NOTES surgery. Of the women polled, nulliparous women and those under age 45 years were significantly more often concerned with how transvaginal surgery may affect healthy sexual life and fertility issues (p < 0.05). Of the women who would not prefer transvaginal surgery, a significant number indicated concerns over infectious issues (p < 0.05). Our study shows that there is considerable public interest in NOTES surgery and women would be receptive to this new surgical technique. Our study highlights a strong need for early reporting of outcomes data to enlighten ourselves, and our patients, about this exciting new technology.
Over-testing for heparin induced thrombocytopenia in hospitalized patients

Heparin induced thrombocytopenia (HIT) is a pro-thrombotic and potentially fatal complication of heparin therapy. Its diagnosis rests on high clinical probability and the laboratory demonstration of anti-PF4/heparin antibodies. The high prevalence of thrombocytopenia in hospitalized patients and the high sensitivity but low specificity of immunoassays for HIT antibodies can lead to over-testing and over-diagnosis. We conducted a study to review HIT screening practices in a tertiary care setting. We reviewed 63 consecutive patients undergoing testing for anti-PF4/heparin antibodies over 3 months. Pre-test probability for HIT was calculated using the 4T score. Sixty three patients underwent testing for anti-PF4/heparin antibodies. Twenty one had been admitted for cardiovascular surgery, 5 for other surgery and 35 for non-surgical indications. Twenty nine patients (46 %) had low pre- test probability, twenty three (36.5 %) had intermediate probability, and eleven (17.4 %) had high pre-test probability of having HIT. Anti-PF4/heparin ELISA was positive in 8 of 63 patients. SRA was ordered for 16 patients and was positive in 5. Only five patients were diagnosed and treated for HIT. Over-testing for HIT is highly prevalent in a tertiary care setting. This increases cost and exposes patients to expensive anti-coagulation with its attendant risk of hemorrhage. The 4Ts score has been shown to have high sensitivity and may be used to rule out HIT in most situations, although its utility depends on subjective analysis. Consistently applying this in practice could minimize over-testing and facilitate safer, cost-effective care.
Lesions of the thalamic intergeniculate leafleet block activity-induced phase shifts in the circadian activity rhythm of the golden hamster

A variety of stimuli, which are associated with acute increases in locomotor activity, induce similar phase-dependent shifts in the circadian rhythm of locomotor activity in golden hamsters. Treatment with the benzodiazepine, triazolam (Tz), or transfer of an animal normally housed without a running wheel to a new cage with 1 h of access to a wheel are both examples of such stimuli. Phase shifts normally induced by injections of Tz can be blocked by lesions of the intergeniculate leaflet (IGL) of the thalamus. Experiments were conducted to determine whether phase shifts induced by transfer to a new cage with a running wheel also require an intact IGL. Animals normally housed without running wheels were transferred to new cages with access to wheels for 1 h a few hours before the expected onset of activity. They then received either lesions of the IGL or sham lesions and, after recovery, they were again transferred to new cages with running wheels for 1 h. Lesions of the IGL blocked phase shifts normally induced by wheel access while sham lesions had no effect. The amount of wheel-running and total locomotor activity which occurred during access to the running wheel were significantly reduced by IGL lesions. These results indicate that the phase-shifting effect of a novel running wheel depends upon an intact IGL.
Advection-dominated Outflows

We obtained self-similar solutions for rotating advection-dominated (no radiative cooling) hydrodynamical bipolar outflows without the presence of a magnetic field. These solutions are two-dimensional and can have arbitrary power-law scaling with radius. The outflow is driven by the pressure, the centrifugal force, and the viscous diffusion, which also transports angular momentum outward. Depending on the density distribution as well as the radial velocity near the equatorial plane of the flow, two types of outflows are found: accretion outflow and ejection outflow. The viscosity parameter (α) affects the outflow in a complicated way, but, in general, high viscosity helps to generate bipolar outflow. Our solutions encompass previously studied cases.
Breast cancer metastases to the pancreas.

Introduction The pancreas can serve as the destination for metastatic spread of malignancies from multiple organ sites. Breast cancer metastases to the pancreas are part of this spectrum and surgeons evaluate such patients as part of their practice. Uniform clinical guidelines for these cases do not exist and care is primarily driven by the personal experience of the treating surgeon.
Switching and Signaling at the Telomere

This review describes the structure of telomeres, the protective DNA-protein complexes at eukaryotic chromosomal ends, and several molecular mechanisms involved in telomere functions. Also discussed are cellular responses to compromising the functions of telomeres and of telomerase, which synthesizes telomeric DNA.
RENAL FAILURE AND POSTOPERATIVE RESPIRATORY FAILURE: RECURARIZATION?

The occurrence of acute postoperative respiratory failure in three patients with renal failure is presented. The most likely cause was the return of muscle paralysis after the apparent antagonism of tubocurarine by neostigmine (recurarization). In addition to reducing the dose of tubocurarine, the authors recommend that pyridostigmine be used as an antagonist instead of neostigmine because the former has a longer duration of action.
Enzyme logic gates for assessing physiological conditions during an injury: Towards digital sensors and actuators

Abstract We describe preliminary results on an enzyme logic sensing system for a reliable assessment of the overall physiological condition during an injury. The new system consists of AND and XOR logic gates based on the concerted operation of tyrosinase, glucose oxidase, lactate dehydrogenase and microperoxidase-11. The enzyme logic system is activated by physiologically relevant concentrations of the input signals of biomarkers: norepinephrine, oxygen, glucose and lactate mimicking in vitro different injuries, including trauma brain injury and hemorrhagic shock. We anticipate that such biochemical logic gates will eventually facilitate decision-making towards the initiation of an optimal timely therapeutic intervention, leading to improved survival of injured soldiers and civilians. The biochemical logic system analyzing biomarker signals represents the first step towards digitally operating sensors and actuators with chemical information processing steps.
Holographic techniques for recording ultrafast events

In this paper we report on a holographic method used to record fast events in the nanosecond time scale. Several frames of the expansion of shock waves in air and in a polymer sample are recorded holographically in a single shot experiment, using a pulse train generated with a single pulse from a Q-switched Nd:YAG laser. The time resolution is limited by the laser pulse width, which is 5.9 ns. The different frames are recorded on the holographic material using angle multiplexing. Two cavities are used to generate the signal and reference pulses at different angles. We also present a method in which the recording material is replaced by a CCD camera. In this method the holograms are recorded directly on the CCD and digitally reconstructed. The holograms are recorded on a single frame of the CCD camera and then digitally separated and reconstructed.
Laser emission from semiconductor microcavities: The role of cavity polaritons

We present an experimental study on the role of cavity polaritons in laser emissions from a GaAs quantum-well microcavity. We show that cavity polaritons play no role in the laser emission process when the cavity is nearly resonant with the excitons. The laser emissions emerge from the bare cavity mode instead of from a cavity-polariton branch and the threshold density is much higher than the saturation density at which cavity polaritons vanish. We also show that the presence of emission doublets near the lasing threshold, which was previously taken as an evidence for laser emission from cavity polaritons, is primarily the result of spatial and/or temporal variations of exciton densities within the excitation volume.
Save your notes, drafts and printouts: today's work is tomorrow's history.

Sydney Brenner and Richard Roberts have a request. If you played a part in the development of molecular biology or biotechnology in the past 50 years, throw nothing away. At least, not before considering what you have to offer to a history of science archive. And, of course, do print anything saved on electronic media on something less ephemeral, like paper.
Near real-time biosensor-based detection of 2,4-dinitrophenol.

Abstract A fluorescent biosensor assay has been developed for near real-time detection of 2,4-dinitrophenol (DNP). The assay was based on fluorescent detection principles that allow for the analysis of antibody/antigen interactions in solution using the KinExA™ immunoassay instrument. Our KinExA™ consisted of a capillary flow observation cell containing a microporous screen that maintains a compact capture antigen-coated bead bed. The bead bed was comprised of polymethylmethacrylate (PMMA) beads coated with dinitrophenol–human serum albumin (DNP–HSA) conjugate. Phosphate buffered saline (PBS) solutions, containing various concentrations of free DNP, were incubated for 30 min with mouse anti-DNP monoclonal antibody to equilibrium. Solutions containing the DNP–monoclonal antibody complex and possible excess free antibodies were then passed over DNP–HSA labeled beads. The free monoclonal anti-DNP antibody, if available, was then bound to the DNP–HSA fixed on the beads. The system was then flushed with excess PBS to remove unbound reactants in the bead bed. The beads were then subjected to brief contact with PBS solutions containing goat anti-mouse fluorescein isothiocyanate (FITC)-labeled secondary antibody, once again, followed by a short PBS flush. The fluorescence was recorded during the addition of the FITC labeled secondary antibody to the bead bed through the final PBS flushing with the KinExA™. The amount of DNP detected could then be determined from the fluorescent slopes that were generated or by the remaining fluorescence that was retained on the beads after final PBS flushing of the system. This assay has been able to detect a minimum of 5 ng/ml of DNP in solution and can be adapted for other analytes of interest simply by changing the capture antigen and antibody pairs.
MM4 Reconciling Decision Models with the Real World: The Cost-Effectiveness of Erythropoietin for Esrd-Related Anemia

The choice of data used in decision modeling of health care interventions divides analysis into two groups: those who favor randomized clinical trial (RCT) data and those who prefer “real world” data. This decision may have serious consequences if the end result is to inform health care policy. This workshop employs a case study to (1) show how differences in the reality of clinical practice and the rigor of RCTs can lead to biases when decision models use RCT data to evaluate policy issues and (2) provide a method of updating decision models with claims/outcomes data to overcome this bias. We highlight three specific problems associated with the use of RCT data which may create misleading results: randomization and sample selection bias, clinically appropriate comparator groups, and indirect treatment effects. These issues are illustrated with a decision model analyzing Medicare's coverage of erythropoietin (EPO) for patients with End-Stage Renal Disease (ESRD). We show how logistic and multiple regression can be used to estimate branch probabilities and payoffs for each treatment group. The incorporation of additional data from the United States Renal Data System into the model enables us to update probabilities and payoffs when patients are not randomly assigned to treatment modalities. To highlight the potential bias that exists when models rely solely on RCT data, we compare our results to a previous study in which the authors employed a computerized decision model to estimate the net costs to Medicare of EPO coverage at 1 and 5 years. This exercise will offer policy analysts and others a method of updating RCT-based decision models to more accurately reflect clinical practice and predict policy effects.
Eye Movements as an Index of Pathologist Visual Expertise: A Pilot Study

A pilot study examined the extent to which eye movements occurring during interpretation of digitized breast biopsy whole slide images (WSI) can distinguish novice interpreters from experts, informing assessments of competency progression during training and across the physician-learning continuum. A pathologist with fellowship training in breast pathology interpreted digital WSI of breast tissue and marked the region of highest diagnostic relevance (dROI). These same images were then evaluated using computer vision techniques to identify visually salient regions of interest (vROI) without diagnostic relevance. A non-invasive eye tracking system recorded pathologists' (N = 7) visual behavior during image interpretation, and we measured differential viewing of vROIs versus dROIs according to their level of expertise. Pathologists with relatively low expertise in interpreting breast pathology were more likely to fixate on, and subsequently return to, diagnostically irrelevant vROIs relative to experts. Repeatedly fixating on the distracting vROI showed limited value in predicting diagnostic failure. These preliminary results suggest that eye movements occurring during digital slide interpretation can characterize expertise development by demonstrating differential attraction to diagnostically relevant versus visually distracting image regions. These results carry both theoretical implications and potential for monitoring and evaluating student progress and providing automated feedback and scanning guidance in educational settings.
Contraction of protoplasm. I. Cinematographic analysis of the anodally stimulated contraction of Spirostomum ambiguum.

Electrically stimulated contraction of Spirostomum ambiguum was investigated by high speed cinematography (up to 6,000 pps). Contraction is completed in about 4 msec following a latent period of up to 30 msec. Reduction in length during contraction followed a sigmoid curve, and final length was about 50% of the original length. Contraction always started at the end of the animal directed towards the anode. When the length of each half was measured separately, it was found that the cathodal end lagged about 1 msec in all cases observed. Rate of contraction was increased when the external calcium contraction was increased, and was decreased in Ca-free and K-free solutions, but was unchanged in K-rich solutions. These results are interpreted in terms of contraction being associated with a relative increase of calcium bound to the contractile protein. The differential migration of potassium and calcium ions in an electric current would result in a temporary lowering of K+ at the anodal end of the animal, hence a relative rise would take place in the Ca++ available for binding. The results of experiments using changed calcium and potassium concentrations can be explained by this hypothesis which is in general agreement with modern work on muscle contraction and relaxation.
Initial testing of a 3D printed perfusion phantom using digital subtraction angiography

Perfusion imaging is the most applied modality for the assessment of acute stroke. Parameters such as Cerebral Blood Flow (CBF), Cerebral Blood volume (CBV) and Mean Transit Time (MTT) are used to distinguish the tissue infarct core and ischemic penumbra. Due to lack of standardization these parameters vary significantly between vendors and software even when provided with the same data set. There is a critical need to standardize the systems and make them more reliable. We have designed a uniform phantom to test and verify the perfusion systems. We implemented a flow loop with different flow rates (250, 300, 350 ml/min) and injected the same amount of contrast. The images of the phantom were acquired using a Digital Angiographic system. Since this phantom is uniform, projection images obtained using DSA is sufficient for initial validation. To validate the phantom we measured the contrast concentration at three regions of interest (arterial input, venous output, perfused area) and derived time density curves (TDC). We then calculated the maximum slope, area under the TDCs and flow. The maximum slope calculations were linearly increasing with increase in flow rate, the area under the curve decreases with increase in flow rate. There was 25% error between the calculated flow and measured flow. The derived TDCs were clinically relevant and the calculated flow, maximum slope and areas under the curve were sensitive to the measured flow. We have created a systematic way to calibrate existing perfusion systems and assess their reliability.
A study of fault tolerance in star graph

The bounds on f(n,k), the number of faulty nodes to make every (n-k)-dimensional substar S"n"-"k in an n-dimensional star network S"n, have been derived. The exact value for f(n,k) is determined when n is prime and k=2, or when n-2=
Human Decision Making Model for Autonomic Cyber Systems

Real-time autonomy is a key element for system which closes the loop between observation, interpretation, planning, and action, commonly found in UxV, robotics, smart vehicle technologies, automated industrial machineries, and autonomic computing. Real-time autonomic cyber system requires timely and accurate decision making and adaptive planning. Autonomic decision making understands its own state and the perceived state of its environment. It is capable of anticipating changes and future states and projecting the effects of actions into future states. Understanding of current state and the knowledge/model of the world are needed for extrapolating actions and deriving action plans. This position paper proposes a hybrid, statistical-formal approach toward achieving realtime autonomy.
Radiative and nonradiative processes in the first excited singlet state of azabenzene vapors

Measurements of fluorescence quenching, fluorescece quantum yields, and triplet formation quantum yields are combined with data in the literature to construct a general picture of S 1 decay in the six azabenzene vapours pyridine, pyrazine, pyrimidine, pyridazine, s -triazine and s -tetrazine. Attention has been directed especially to S 1 -T crossing from the S 1 zero point level, except for s -triazine in which the crossing from the 677 cm −1 fundamental ( v ′ 6 ) has been characterized. No evidence for triplet formation is found for pyridazine and s -tetrazine. A fast collision-free channel leading ultimately to dissociation probably dominates S 1 decay in these molecules. Triplet formation occurs in the remaining four azabenzenes, and the fluorescence quenching in three (pyridine fluorescene could not be detected) shows that in those cases the S 1 -T crossing is collision induced. Firm evidence concerning the effect of collisions on triplet formation in pyridine could not be obtained. The triplet yields reach a maximum limiting value as added gas pressures become high enough so that collisional channels dominate S 1 decay. This value is unity in pyrazine and pyrimidine; in pyridine and s -triazine it is about 0.5. An unidentified collisional channel competes effectively with collision-induced crossing in s -triazine and probably in pyridine as well. The fluorescence quantum yields extrapolated to zero pressure are less than 10 −2 in every azabenzene except pyrimidine where the yield is ⩾0.3. Pyrazine remains the only azabenzene vapor in which phosphorescence has been observed.
Droplet-size effects and lighting techniques in direct-view PDLC displays

— By varying liquid-crystal droplet sizes in designated regions, direct-view polymer-dispersed liquid-crystal (PDLC) displays with simpler addressing schemes are constructed. A multiple-droplet-size PDLC is used to hide addressing-line voltage effects in a segmented display which requires a clear (non-scattering) region surrounding the segments. Edge lighting improves the contrast ratio of these direct-view displays.
Lyapunov Direct Design of Robust Control for Electrical-Mechanical Systems Composed of Cascaded Nonlinear Uncertain Subsystems

Robust control design of non linear uncertain systems is investigated. A system under consideration consists of finite nonlinear systems which are cascaded and have significant uncertainties. Such a system arises naturally from many real physical systems, especially mechanical systems. An important feature of these systems is that they do not satisfy the assumption of the standard matching conditions required by most existing robust control results. General classes of cascaded uncertain systems are identified for which robust controllers are obtained explicitly in terms of the bounding functions of the uncertainties. The resulting robust controllers guarantee stability of global uniform ultimate boundedness or global exponential convergence to zero. The controls are designed by a two-step systematic design procedure. First, design fictitious robust controllers for input of individual sybsystem as if every subsystem had an independent control. Then, a recursive mapping is proposed which maps the individual fictitious controls recursively into the only control of the overall system
Finite element derivative recovery by moving least square interpolants

Abstract A simple, accurate technique for recovery of displcements and derivatives, such as strains is presented. The technique is based on local interpolation of nodal displacements using a moving least square method. The strains are then recovered by taking appropriate derivatives of this interpolant. Numerical experiments in linear elasticity and heat conduction on the convergence and accuracy of the recovered derivatives show very good results and superconvergence for strains in many cases; the technique is also effective for displacement interpolation for projection methods.
STUDY OF NANOPOROUS MEMBRANES WITH APPLICATIONS IN THE ENHANCED DETECTION OF CADIOVASCULAR BIOMARKER PROTEINS

The goal of this work is to understand the role of nanoconfinement in designing molecular biosensors. We have been investigating microdevices incorporated with nanoporous membranes as molecular biosensor platforms. Detection of ultra low concentration of biomolecules is the key expectation from the new class of molecular biosensors utilizing nanomaterial. In this paper we have evaluated the role of the physical attributes of nanoporous aluminum oxide membranes in nanoconfinement and enhancing sensitivity of detection of protein biomolecules. In this biosensor configuration we have generated a sandwich assay in a high density array of nanoscale confined spaces generated by overlaying the nanoporous alumina membrane over metallic microscale sensing sites. The binding of the biomolecules results in the perturbation of the electrical double layer due to the binding of the test protein (C-reactive protein). Using electrical impedance spectroscopy (EIS), the capacitance changes in the electrical double layer associated with specific protein binding has been evaluated. The sensor performance metrics of sensitivity and dynamic range have been analyzed with changes in the pore diameter.
Adenomatous polyp of the right main bronchus producing atelectasis

Summary A case of an adenomatous polyp of the right main bronchus in a boy eleven years old is described. The clinical picture was that of atelectasis and bronchiectasis of the right lower lobe with a triangular basal shadow on the roentgenogram. After bronchoscopic removal of the neoplasm, the clinical state was considerably improved, and two months later the triangular basal shadow had almost disappeared.
An Experimental Investigation of the Quasi-Steady Assumption in Speech

Human speech is initiated when the lungs achieve a critical pressure forcing the vocal folds apart, expelling air through the glottis, and beginning self-sustained oscillations. The oscillations arise due to coupling between the aerodynamic forces and the structural properties of the vocal folds. During each phonation cycle the glottis transitions from a convergent channel upon opening, to a uniform, and finally a divergent channel before closing and repeating the cycle. The resulting pulsatile flow field which emanates from the vocal folds forms the raw component of speech.Copyright © 2009 by ASME
Optically sensitive MCP image tube with a Medipix2 ASIC readout

We present the first results from the successful fabrication of an optical imaging tube consisting of a pair of MCPs read out by a CMOS application specific integrated circuit (ASIC) developed for x-ray imaging called the Medipix2. The Medipix2 is an array of 256×256 pixels, each of which amplifies and counts individual photon stimulated events amplified by the MCPs. A multi-alkali photocathode installed in proximity focus above the MCP is used for conversion of incoming photons into photoelectrons.. The Medipix2 integrates these detected photons, and the binary values of these counters is read fast (~ 1kHz frame rate) and without readout noise. Initial imaging tests of this tube, including QE, resolution, background, dynamic range and microsecond shutter operation are presented..
Multidimensional interleaving for synchronous circuit design optimization

This paper presents a novel optimization technique for the design of application specific integrated circuits dedicated to perform iterative or recursive time-critical sections of multidimensional problems, such as image processing applications. These sections are modeled as cyclic multidimensional data flow graphs (MDFGs). This new optimization technique, called multidimensional interleaving, consists of a multidimensional expansion and compression of the iteration space, followed by a multidimensional retiming, while considering memory requirements. It guarantees that all functional elements of a circuit can be executed simultaneously, and no additional memory queues proportional to the problem size are required. The algorithm runs optimally in O(|E|) time, where E is the set of edges of the MDFG representing the circuit. Our experiments show that the additional memory requirement is significantly less than the results obtained in other methods.
Assessing invasive alien species across multiple spatial scales: working globally and locally

Quantitative investigations on invasive alien species (IAS) across multiple spatial scales are needed because biological invasions often encompass enormous expanses in both donor and invaded ranges and because the immigrants may be carried great distances between these ranges. Although invasion biology is rich in anecdotes, translation of this information into generalizations remains limited by technical shortcomings in data acquisition, inconsistent data assembly, and the continuing search for meaningful indices of the impact of IAS. Much better justification of and greater opportunities to combat IAS could be achieved by distilling all information for IAS into spatially explicit case histories and synthetic predictions on the epidemiology and consequences of biological invasions for public review, discussion, and action. Las investigaciones cuantitativas sobre las especies exoticas invasoras (EEI) a traves de numerosas escalas espaciales son necesarias porque las invasiones biologicas abarcan a menudo e...
Autonomy and Perceptions of Work Quality: Drive the job satisfaction of TV news workers

Self-determination theory says intrinsic and extrinsic motivations influence our goal-oriented behavior and determine satisfaction. For TV news workers, those motivations include deadlines, breaking news, multiple-screen obligations, competition, and the desire to produce quality journalism each day. In this study of nearly 900 broadcasters, those with work autonomy and organizational support have a great deal of job satisfaction and say they are producing a high quality of journalism. Of the sample, 19 percent (N = 155) who said they intend to leave TV news within five years had significantly lower levels of job satisfaction, organizational support, autonomy, and perceptions of work quality. The primary reasons for leaving the industry include salary, family issues, and concerns about the quality journalism they are producing.
Raman spectroscopic studies of oral cancers: correlation of spectral and biochemical markers

Both ex vivo and in vivo oral cancer studies performed using Raman spectroscopy over the past decade have demonstrated that the spectra of normal tissues are rich in lipids, while tumors have predominant protein features. However, in view of the variability in the Raman scattering cross section of biomolecules, it is pertinent to explore spectral features vis-a-vis biochemical composition in order to verify spectral markers as biochemical markers. Spectra of 20 pairs of normal and tumor oral tissues were acquired using a fiber optic probe coupled with a Raman spectrometer. The intensity associated with lipid (1440 cm−1) and protein (1450 and 1660 cm−1) bands were computed and correlated with the biochemical estimation for proteins, lipids, and phospholipids from the same tissues. The intensity of the lipid band was higher in normal tissues, while that of the protein band was higher in tumors. Biochemical estimation yielded similar results, i.e., high protein-to-lipid or -phospholipid ratio in tumors with respect to normal tissues. These differences were found to be statistically significant. Findings of curve-deconvolution and biochemical estimation correlate well and suggest that spectral features are the hallmark of underlying biochemical tissue composition.
Improvement Without Value.

We read with interest the quality report by Kurowski et al, titled “Improvement Methodology Increases Guideline Recommended Blood Cultures in Children With Pneumonia.” We applaud the authors for their successful implementation and description of a complex project using quality improvement methods. The first question in the model for improvement is: “What are we trying to accomplish?” Perhaps a second question should be added: “Why?” Kurowski et al cite compliance with the 2011 Pediatric Infectious Diseases Society/Infectious Diseases Society of America guidelines and “to standardize management” to support their aim. In their project, they increased the percent of blood cultures performed in … E-mail: quinonez{at}bcm.edu
Analysis and Algorithms for the Transtainer Routing Problem in Container Port Operations

The problem of minimizing the time taken to load the containers from the container stack yard onto the ship is called the transtainer routing problem. We first do a theoretical investigation of the problem to understand the structural properties of the problem. We then use these results to prove that the problem isNP-Complete. The problem is then formulated as an integer program. A branch-and-bound based enumerative method is developed to obtain an exact solution to the problem. An algorithm to solve the matching problem on a line at the root node of the branch-and-bound tree is developed. Several lower bounds to prune the size of the tree are also developed. A result which states that there cannot exist a polynomial time heuristic with a bounded worst case unlessP =NP is proved. Based on this result, an enumerative heuristic with a worst-case performance ratio of 1.5 is designed. Computational tests on randomly generated problems are conducted to evaluate the exact and heuristic algorithms.
Guanylyl cyclase sees the light

Cyclic guanosine monophosphate (cGMP) is a critical second messenger that regulates cardiovascular function and vision in humans. Two recent papers, including one in BMC Structural Biology, have revealed atomic structures of the enzymes that catalyze the synthesis of cGMP providing new clues about the molecular basis of substrate specificity and allosteric regulation in nucleotide cyclases.
The Use of Amplitude Integrated Electroencephalography for Assessing Neonatal Neurologic Injury

Amplitude-integrated electroencephalography (aEEG) plays an important role in integrated care of the full-term infant with neonatal encephalopathy. The three main features that are provided with aEEG are the background pattern on admission and the rate of recovery seen during the first 24 to 48 hours after birth, the presence of most electrographic discharges, and the effect of antiepileptic drugs.
The Olivocerebellar System as a Generator of Temporal Patterns

The large number of diverse functions attributed to the cerebellum appears to be inconsistent with its simple, homogeneous and evolutionary preserved structure. A homogeneous structure that participates in a variety of functions implies that a common denominator underlies all of them. Since the concept of precise timing can be recognized in almost all cerebellar functions, it is likely, therefore, that the basic cerebellar circuit is capable of generating temporal patterns. Of the different mechanisms that can generate temporal patterns, two are suggested by the functional anatomy of the cerbellum: transmission lines or oscillators. Our recent experimental observations indicate that the olivary oscillatory property is more likely to serve this function. We propose that interactions between the cerebellum and the inferior olive endow the system with the ability to generate complex temporal patterns. These temporal patterns can be used for fine adjustment of motor output, sensory expectation, or shifting attentions.