cssi/SciSciGPT-SciSciNet huggingface dataset:
Spectra and structure of organophosphorus molecules. LXII. Conformational stability of (methylthio)dichloro phosphine from temperature-dependent infrared spectra of krypton solutions, structural parameters and ab initio calculations

Abstract Variable temperature (−105 to −150°C) studies of the infrared spectra (3500–400 cm −1 ) of (methylthio)dichlorophosphine, CH 3 SPCl 2 , dissolved in liquid krypton have been carried out. Utilizing the conformer bands at 518, 511and 1319 cm −1 ( gauche ) and 1311 cm −1 ( trans ), an enthalpy difference of 306±25 cm −1 (3.66±0.30 kJ/mol) was obtained with the trans conformer, the more stable form. The trans conformer also remains in the infrared and Raman spectra of the polycrystalline solid. At ambient temperature, there is approximately 72% of the trans conformer present. The optimal geometries, conformational stabilities, harmonic force fields, infrared intensities, Raman activities, depolarization ratios and vibrational frequencies are reported for both conformers from ab initio calculations. These calculations were carried out at the restricted Hartree–Fock (RHF) level and/or with electron correlation to second order (MP2), utilizing the basis sets 6-31G(d), 6-311+G(d,p) and 6-311+G(2d,2p). At the highest level of calculations, MP2/6-311+(2d,2p), the trans conformer is predicted to be more stable by 587 cm −1 , which is in reasonable agreement with the experimental results. The coefficients from the potential function governing the conformational interchange have been obtained from the MP2/6-31G(d) ab initio calculations. The other calculated quantities are compared with the experimentally determined values where applicable, as well as some corresponding results for some similar molecules.
ENHANCED COLLAGEN ACCUMULATION FOLLOWING DIRECT TRANSFECTION OF THE INDUCIBLE NITRIC OXIDE SYNTHASE GENE IN CUTANEOUS WOUNDS

Inducible nitric oxide synthase (iNOS) is expressed during cutaneous wound repair. Mounting evidence suggests that wound nitric oxide (NO) augments collagen accumulation. We hypothesized thatin vivotransfection of wound cells with the iNOS gene would increase physiological wound NO levels and thus augment collagen accumulation. Polyvinyl alcohol sponges were instilled with a mammalian expression plasmid (pMP6) containing either the chloramphenicol acetyl transferase (CAT) reporter or murine iNOS gene driven by a CMV immediate-early promoter. Plasmid DNA was injected alone or in complex with cationic liposomes, and the sponges were placed subcutaneously in male Sprague–Dawley rats which had received a longitudinal dorsal midline incision. Animals were sacrificed at different time points post-wounding and the sponges assayed for CAT activity, transfected iNOS mRNA, total nitrate and nitrite concentration (NOX) (as an index of wound NO synthesis), and hydroxyproline content (as an index of sponge collagen accumulation). The results demonstrate that wound cells were more efficiently transfected by naked DNA than by liposome mediated transfection and that maximal expression of both iNOS and CAT occurred at 48 hrs with a rapid decline after this time point. After 7 days, iNOS transfected sponges had accumulated significantly more collagen than those transfected with CAT. We conclude that cutaneous wounds can be successfully transfected by direct injection of naked DNA and that increased iNOS expression precedes an increase in collagen synthesis.
An analytical and computational investigation of shock-induced vortical flows

Interaction of a shock wave with a jet of light gas surrounded by an ambient heavy gas generates vorticity around the perimeter of the jet. This rolls the jet into a pair of counterrotating, finite-core size vortices. The canonical problem is the two-dimensional, unsteady interaction in a finite channel. The dynamics of the vortex pair are controlled by the incident shock strength, the light/heavy gas density ratio, and the channel spacing. Analytical expressions are derived which describe the strength and motion of the vortex pair as a function of these parameters. Numerical simulations shQw good agreement with these models. Various perturbations on the single jet flow are investigated with the goal of destabilizing the vortex pair and further enhancing the mixing. Single jet shape perturbations are relatively ineffective. However, an array of jets can dramatically increase the mixing. Another effective method is to form a reflected shock. Finally, an analogy to the corresponding three-dimensional, steady flows is demonstrated both qualitatively and quantitatively. This allows an understanding of the dynamics and mixing of the two imensional, unsteady flows to be directly applied to three-dimensional, steady flows typical of SCRAMJET designs.
Consequences of Epithelial or Stromal TGFβ1 Depletion in the Mammary Gland

Transforming growth factor β1 (TGFβ) affects stroma and epithelial composition and interactions that mediate mammary development and determine the course of cancer. The reduction of TGFβ in Tgfβ1 heterozygote mice, which are healthy and long-lived, provides an important model to dissect the contribution of TGFβ in mammary gland biology and cancer. We used both intact mice and mammary chimeras in conjunction with Tgfβ1 genetic depletion and TGFβ neutralizing antibodies to evaluate how stromal or epithelial TGFβ depletion affect mammary development and response to physiological stimuli. Our studies of radiation carcinogenesis have revealed new aspects of TGFβ biology and suggest that the paradoxical TGFβ switch from tumor suppressor to tumor promoter can be resolved by assessing distinct stromal versus epithelial actions.
Sustainable Engagement? Reflections on the development of a creative community-university partnership

Recognising the untapped potential of multiple discrete community-university partnerships (CUPs) in San Francisco, San Francisco’s Neighborhood Empowerment Network (NEN) and the Institute for Civic and Community Engagement at San Francisco State University are in the midst of creating a collaborative community-university partnership called NEN University (NENu),which includes other Bay Area institutions of higher education as well as city agencies, non-profit organisations, businesses and neighbourhood resident leaders. This article reflects on the author’s experiences and observations in the ‘doing’ of engaged scholarship as it relates to NENu over the past two years. It contributes to the discussion of how best to build sustainable (in that they have staying power beyond the commitment of a few key individuals) and effective (in terms of building or strengthening communities) CUPs. In so doing it offers a framework for understanding possible threats to the sustainability of CUPs and applies that framework to an account of NENu’s partnership development process. The article concludes with implications for research and practice. Keywords community-university partnership; engaged scholarship; leadership; sustainability
Advances In The Application Of Holography For NDE

Several recent applications of holographic interferometry to nondestructive testing are described and the basic methodology is discussed. Applications to the detection of cracks, particularly in ceramic materials, including a crack 50 μm in depth are given. A non-destructive method to quantify the gradual erosion of calcareous stones exposed to acid rain is presented.
Antarctic O3: Chemical mechanisms for the spring decrease

Chemical explanations for the spring decline of Antarctic O3 involve reactions of ClO or interactions between BrO and ClO. Reaction schemes involving Br radicals have the highest efficiency for removal of O3. The chemical mechanisms require low levels of NO(x). Recent cooling of the stratosphere may have triggered formation of HNO3 monohydrate, removing NO(x) and setting the stage for enhanced loss of ozone over Antarctica.
Composition stability limits for the rocksalt-structure phase (Pb1−ySny)1−xTex from lattice parameter measurements

The parameter values measured are in agreement with those reported by Mazelsky and Lubell (1963) and data of Bis and Dixon (1969). The measurements for SnTe introduce a large amount of data into a defect model analysis that shows that the ratio of the number of holes per tin-vacancy acceptor to the 77 K Hall factor is independent of the apparent hole concentration. The measurements reveal some interesting problems in handling the Sn-rich alloys in fine powder form due to the uptake of oxygen.
“JUST TESTING” Race, Sex, and the Media in New York's “Baby AIDS” Debate

In 1993, debates over mandatory HIV testing reemerged in New York when politicians and journalists launched a compaign to “unblind” results of a survey of HIV prevalence in newborns. This article reports on the findings from a content analysis of 108 “Baby AIDS” news stories published in New York newspapers in 1993 and 1994. In constructing a discourse of blame for the infection of “innocent” babies, “Baby AIDS” news stories demonstrate that racist, heterosexist, and sexist assumptions about HIV transmission, motherhood, and public HIV surveillance are fundamentally intertwined. The article concludes that arguments by AIDS analysts that homophobia and racism are distinct and independent dimensions of policy and popular understandings of HIV are not only misguided but also dangerous.
Any two irrational rotations are nearly continuously Kakutani equivalent

Ergodic homeomorphisms T and S of Polish probability spaces X and Y are evenly Kakutani equivalent if there is an orbit equivalence ϕ: X0 → Y0 between full measure subsets of X and Y such that, for some A ⊂ X0 of positive measure, ϕ restricts to a measurable isomorphism of the induced systems TA and Sϕ(A). The study of even Kakutani equivalence dates back to the seventies, and it is well known that any two irrational rotations of the circle are evenly Kakutani equivalent. But even Kakutani equivalence is a purely measurable relation, while systems such as irrational rotations are both measurable and topological.
Attention and multidimensional discrimination1

Observers’ ability to perform several discrimination tasks at the same time was tested using a two-alternative temporal forced-choice procedure. Discrimination of two auditory dimensions (pitch and intensity) and two visual dimensions (horizontal position and vertical position) was measured under conditions where one, two or all four dimensions required attention. Three signal durations were used: 67, 133, and 200 msec. Increasing the number of dimensions requiring attention systematically reduces the precisions of discrimination for each dimension. Auditory and visual discrimination is affected similarly. The amount of reduction in discrimination is independent of whether the dimensions requiring attention involve the same or different sensory modalities. The data are analyzed for evidence of a constant processing capacity employed in both single and multidimensional discrimination. The possibility that the observed performance levels could be achieved by sequentially processing the simultaneous inputs is also considered.
Living in a physical world VI. Gravity and life in the air.

In our perceptual world, no physical agency imposes itself with greater immediacy than does gravity. We depend on it to walk or run; it injures us if we trip. It makes each of us about half a centimeter shorter at the end of each day than when we first arise. Our flesh sags as we age; more slowly, the glass of a window thickens at the bottom and thins at the top. We dream of escaping its constant crush, although our recent experiences in orbiting spacecraft reveal an addiction with a difficult withdrawal. Physicists may regard the gravitational attraction between two objects as the universe’s definitional weak force, but to us large, terrestrial creatures it feels anything but weak. Since the consequences of gravity depend on one’s size, scaling will loom at least as large in this and then the next as in any of the preceding essays. Even more important than the ways gravity’s effects, scale will be another message–the surprisingly wide range of biological situations in which it plays some role. One knows that no massless world exists; I would argue that a weightless world is almost as hard to imagine. That contrast, mass versus weight, needs a few words. Newtonian mechanics lumped two distinct kinds of mass, inertial mass and gravitational mass. Establishing the basis of their apparent equality awaited the 20th century. An inertial mass resists acceleration, as expressed in Newton’s first and second laws; quantitatively, mass equals force divided by acceleration–the familiar F = ma. Weight follows from the other kind of mass. A gravitational mass attracts any other mass, exerting a force equal to the product of the two masses, divided by the square of the distance between them, times a universal gravitational constant, in proper SI units, 6.67 × 10 -11 N m 2 kg -2 . (One should avoid using “gravitational constant” for the acceleration of gravity at the surface of the earth, commonly designated g.) In our world that other mass is that of the earth itself, 5.976 × 10 24 kg, and the basic distance is that from the earth’s surface to its center of mass, 6,370 km. These data give g = 9.8 m s-2; with F = mg
Modification of irradiation effects through actively acquired tolerance to homologous bone marrow grafts.

SummaryHost and donor pigeons made immunologically tolerant in various combinations by skin grafting shortly after hatching were exposed to lethal doses of irradiation at the age of 8–10 months. Homologous bone marrow transplants gave the following results:1) The tolerant state of the host did not appreciably affect survival; i.e., mean survival of Group 1 (host tolerant of donor) was 23.4 ± 5.6 and of Group 4 (no known tolerance) was 25.3 ± 4.1 days.2) Tolerance of marrow donors for host increased mean survival by about 10 days (34.2 ± 4.3 for Group 2 and 35.6 ± 5.2 for Group 3). Differences in mean survival between combined Groups 1, 4 and 2, 3 were statistically significant (p<.05).3) These data suggest that the immunologic mechanism of the donor is more important than that of the host in producing “homologous disease” in the pigeon.
Changes in hypothalamic catecholamines and serotonin during hibernation and arousal in the arctic ground squirrel.

Abstract 1. 1. Hypothalamic norepinephrine (NE), epinephrine (E) and serotonin (5-HT) were assayed and compared in the Arctic ground squirrel ( Citellus undulatus ) in the prehibernation summer season and different phases of the hibernation cycles during the winter. 2. 2. From a high level in the prehibernation season, NE fell (by 35 per cent) to a lower level in the hibernation period, active phase and re-entry phase of the hibernation cycle. In early and mid arousal, NE increased by 50 per cent over that in deep hibernation. By the end of arousal, NE returned to the level found in other phases of the hibernation cycle. 3. 3. During the hibernation cycle, E increased in late arousal and the active phase. The concentration of 5-HT remained similar in all groups except in early arousal when the level was 34 per cent lower than that in hibernation. 4. 4. The ratio of NE/5-HT in the hypothalamus was highest during early arousal from hibernation. 5. 5. The results support the hypothesis that changes in the activity of hypothalamic noradrenergic and serotonergic systems play an important role in maintenance of and arousal from hibernation.
Partial coverage in crown and bridge prosthesis with the use of elastic impression materials

Abstract A review of some aspects of partial coverage abutments has been presented to broaden the understanding of them, and to encourage the use of these restorations. Until research has resolved some of the conflicting theories of contour, occlusion, splinting, and materials, conservative dentistry should be our objective. The response of soft and hard oral tissues to our restorative procedures is the best indicator of their value, and the pursuit of careful conservative techniques should not be discarded in favor of full coverage.
Fast iterative methods for discrete-ordinates particle transport calculations

Abstract In discrete-ordinates (S N ) simulations of large problems involving linear interactions between radiation and matter, the underlying linear Boltzmann problem is discretized and the resulting system of algebraic equations is solved iteratively. If the physical system contains subregions that are optically thick with small absorption, the simplest iterative process, Source Iteration, is inefficient and costly. During the past 40 years, significant progress has been achieved in the development of acceleration methods that speed up the iterative convergence of these problems. This progress consists of ( i ) a theory to derive the acceleration strategies, ( ii ) a theory to predict the convergence properties of the new strategies, and ( iii ) the implementation of these concepts in production computer codes. In this Review we discuss the theoretical foundations of this work, the important results that have been accomplished, and remaining open questions.
On the interaction of syntactic subject, thematic information, and agent in english☆

Abstract A detailed analysis of texts of the play-by-play action of ice hockey taken from videotaped games shows that for English the function of a syntactically defined subject is to encode primarily thematic information and secondarily agent. That is, when several NPs compete for the subject relation, and it can be determined that one NP is the most thematic, then that NP will occur in the subject relation independent of its semantic role. But when no NP is more thematic, the subject will then take the agent.
Overexpression and constitutive nuclear localization of cohesin protease Separase protein correlates with high incidence of relapse and reduced overall survival in glioblastoma multiforme

Separase, an enzyme that cleaves the chromosomal cohesin during mitosis, is overexpressed in a wide range of human epithelial cancers of breast, bone and prostate (Meyer et al., Clin Cancer Res 15(8):2703–2710, 2009). Overexpression of Separase in animal models results in aneuploidy and tumorigenesis. We have examined the expression and localization of Separase protein in adult and pediatric glioblastoma and normal brain specimens. Immunofluorescence microscopy and Western blot analysis showed significant overexpression of Separase in all adult and a subset of pediatric glioblastoma cells. Tumor status and patient survival strongly correlate with the mislocalization of Separase into the nucleus throughout all stages of the cell cycle. Unlike exclusively nuclear localization in mitotic control cells, glioblastoma samples have a significantly higher number of resting (interphase) cells with strong nuclear Separase staining. Additionally, patient survival analysis demonstrated a strong correlation between overexpression of Separase protein in adult glioblastoma and a high incidence of relapse and reduced overall survival. These results further strengthen our hypothesis that Separase is an oncogene whose overexpression induces tumorigenesis, and indicate that Separase overexpression and aberrant nuclear localization are common in many tumor types and may predict outcome in some human malignancies.
Geologic evidence of earthquakes at the Snohomish delta, Washington, in the past 1200 yr

Exposed channel banks along distributaries of the lower Snohomish delta in the Puget Lowland of Washington reveal evidence of at least three episodes of liquefaction, at least one event of abrupt subsidence, and at least one tsunami since ca. A.D. 800. The 45 measured stratigraphic sections consist mostly of 2‐4 m of olivegray, intertidal mud containing abundant marsh plant rhizomes. The most distinctive stratigraphic unit is a couplet comprising a 0.523-cm-thick, laminated, fining-upward, tsunami-laid sand bed overlain by 2210 cm of gray clay. We correlated the couplet, which is generally ;2 m below the modern marsh surface, across an ;20 km2 area. Sand dikes and sand-filled cracks to 1 m wide, which terminate upward at the couplet, and sand volcanoes preserved at the level of the sand bed record liquefaction at the same time as couplet deposition. Differences in the type and abundance of marsh plant rhizomes across the couplet horizon, as well as the gray clay layer, suggest that compaction during this liquefaction led to abrupt, local lowering of the marsh surface by as much as 50‐75 cm. Radiocarbon ages show that the tsunami and liquefaction date from ca. A.D. 800 to 980, similar to the age of a large earthquake on the Seattle fault, 50 km to the south. We have found evidence for at least two, and possibly as many as five, other earthquakes in the measured sections. At two or more stratigraphic levels above the couplet, sand dikes locally feed sand volcanoes. Radiocarbon ages and stratigraphic position gov. suggest that one set of these dikes formed ca. A.D. 910‐990; radiocarbon ages on a younger set indicate a limiting maximum age of A.D. 1400‐1640. We also interpret a sharp lithologic change, from olive-gray, rhizome-rich mud to grayer, rhizome-poor mud, ;1 m above the couplet, to indicate a second abrupt lowering of the marsh surface during an earthquake ca. A.D. 1040‐ 1400, but no conclusive liquefaction structures have been identified at this horizon. Two distinctive coarse-sand laminae, 30‐80 cm below the couplet, may record tsunamis older than A.D. 800. Thus, study shows that in the past ;1200 yr, this part of Washington’s Puget Lowland has been subjected to stronger ground shaking than in historic times, since ca. 1870.
Hybrid ALOHA: A Novel MAC Protocol

This paper considers cross-layer medium access control (MAC) protocol design in wireless networks. Taking a mutually interactive MAC-PHY perspective, we aim to design an MAC protocol that is in favor of the physical (PHY) layer information transmission, and the improved PHY, in turn, can improve the MAC performance. More specifically, we propose a novel MAC protocol, named hybrid ALOHA, which makes it possible for collision-free channel estimation and simultaneous multiuser transmission. The underlying argument is as follows: As long as good channel estimation can be achieved, advanced signal processing does allow effective signal separation given that the multiuser interference is limited to a certain degree. Comparing with traditional ALOHA, there are more than one pilot subslots in each hybrid ALOHA slot. Each user randomly selects a pilot subslot for training sequence transmission. Therefore, it is possible for different users to transmit their training sequences over nonoverlapping pilot subslots and achieving collision-free channel estimation. Relying mainly on the general multipacket reception (MPR) model, in this paper, quantitative analysis is conducted for the proposed hybrid ALOHA protocol in terms of throughput, stability, as well as delay behavior. It is observed that significant performance improvement can be achieved in comparison with the traditional ALOHA protocol based either on the collision model or the MPR model.
A lightweight intelligent virtual cinematography system for machinima production

Machinima is a low-cost alternative to full production filmmaking. However, creating quality cinematic visualizations with existing machinima techniques still requires a high degree of talent and effort. We introduce a lightweight artificial intelligence system, Cambot, that can be used to assist in machinima production. Cambot takes a script as input and produces a cinematic visualization. Unlike other virtual cinematography systems, Cambot favors an offline algorithm coupled with an extensible library of specific modular and reusable facets of cinematic knowledge. One of the advantages of this approach to virtual cinematography is a tight coordination between the positions and movements of the camera and the actors.
CHEMOPATHOLOGICAL STUDIES WITH COMPOUNDS OF ARSENIC : IV. THE CHARACTER AND DISTRIBUTION OF RENAL INJURY PRODUCED BY ARSENICALS AS INDICATED BY THE PROCESSES OF REPAIR.

1. The processes of repair in the kidneys of guinea pigs after sublethal doses of certain arsenical compounds indicate that all arsenicals do not produce a purely vascular type of renal injury. 2. While some arsenicals produce a predominantly vascular injury and others produce a predominantly tubular injury, both these tissue elements are undoubtedly always affected, although in varying proportion. In addition, the interstitial connective tissue is probably always affected. The diffuse proliferation of this tissue may be relatively conspicuous in the processes of repair after arsenicals that cause but slight vascular injury. 3. All red kidneys do not necessarily show identical pictures during the processes of repair; the same is true of pale kidneys. 4. The mode of action of an arsenical compound as a renal toxic agent is bound up with the chemical constitution of the compound.
Vibrations of the Amino Group in Glycine Hydrochloride: Spectral Hole Burning and Isotope Shifts

Hole burning of the N−D stretches of the deuterium-doped glycine hydrochloride results in holes and antiholes in the various regions of the spectrum. These can be assigned to various orientations of the NH2D+ moiety. Bands at about 800 cm-1 are probably the amino group rocks, but the other changing bands must arise from complex mixtures of the valence vibrations. The hole burning takes considerable time, on the order of 1 h, and puts most of the NH2D+ in the orientation of lowest energy.
Stability of modulation transfer function calibration of surface profilometers using binary pseudo-random gratings and arrays with nonideal groove shapes

The major problem of measurement of a power spectral density (PSD) distribution of surface heights with surface profilometers arises due to the unknown modulation transfer function (MTF) of the instruments, which tends to distort the PSD at higher spatial frequencies. The special mathematical properties of binary pseudo-random patterns make them an ideal basis for developing MTF calibration test surfaces. Two-dimensional binary pseudo-random arrays have been fabricated and used for the MTF calibration of the MicroMap TM -570 interferometric microscope with all available objectives. An investigation into the effects of fabrication imperfections on the quality of the MTF calibration and a procedure for accounting for such imperfections are presented.
In Brief: Nonalcoholic Fatty Liver Disease

1. Bryan Rudolph, MD 2. Yolanda Rivas, MD 1. Children's Hospital at Montefiore Bronx, NY Nonalcoholic fatty liver disease (NAFLD) is a generic term encompassing a spectrum of disorders defined by their histopathology. On one end of the continuum is simple macrovesicular steatosis, which is defined by large fat droplets within hepatocytes. Over time, however, simple steatosis may progress. When inflammation is present, with or without fibrosis, the condition is known as nonalcoholic steatohepatitis (NASH). The far end of the spectrum is frank cirrhosis. All of the entities constituting NAFLD are associated with obesity and insulin resistance and, by definition, occur in the absence of alcohol consumption. First described in the pediatric literature just over 25 years ago, NAFLD today is recognized as an increasingly significant cause of liver disease. Estimates of the overall prevalence of NAFLD vary, based on the method of detection, but it likely is present in approximately 9% of all children and in up to 80% of obese children. With the obesity epidemic and increased physician awareness, these figures are almost sure to increase. Currently, the average age at diagnosis is 12 years, with the earliest reported cases at about 2 years of age. Evidence also suggests that children are developing more advanced stages of NAFLD at earlier ages. In 2006, for example, it was estimated that 25% of …
Daily movements, habitat use, and submergence intervals of normal and tumor-bearing juvenile green turtles (Chelonia mydas L.) within a foraging area in the Hawaiian islands

Depth-sensitive ultrasonic transmitters monitored the horizontal and vertical movements of 12 juvenile (<65 cm carapace length) green turtles (Chelonia mydas L.) in Kaneohe Bay, Oahu (Hawaii, USA). This site was chosen because of its accessibility, its importance as a foraging area, and the high incidence (≈50%) of fibropapillomatosis, a tumor disease of unknown etiology. Our objectives were to determine the daily movements, habitat use, and submergence intervals of normal and tumor-bearing animals. The presence of tumors had no obvious effects on movement patterns or habitat use. All turtles remained within a small portion of the bay where patch reefs and shallow coral-covered areas are common, and algal growth most abundant. During daylight, two normal and two tumor-bearing animals remained within known feeding areas, all other turtles studied stayed within deep mud bottom channels or within crevices on the sides of reefs. All, except one tumor-bearing turtle, moved up on to shallow patch reefs or shallow coral-covered areas at night. Submergence intervals for both groups were short (over 90% were 33 min or less and none exceeded 66 min) compared to maximum breath-hold times (up to 5 h) measured in the laboratory by earlier workers. Juvenile green turtles in Hawaii, therefore, most likely maintain aerobic metabolism while submerged and surface before oxygen stores are significantly depleted. Tumor-bearing turtles had a higher frequency of longer submergence intervals during the night, indicating they may have been somewhat less active at night. Normal turtles showed no such day-night difference.
Automatic segmentation of the facial nerve and chorda tympani in CT images using spatially dependent feature values

In cochlear implant surgery, an electrode array is permanently implanted in the cochlea to stimulate the auditory nerve and allow deaf people to hear. A minimally invasive surgical technique has recently been proposed—percutaneous cochlear access—in which a single hole is drilled from the skull surface to the cochlea. For the method to be feasible, a safe and effective drilling trajectory must be determined using a preoperative CT. Segmentation of the structures of the ear would improve trajectory planning safety and efficiency and enable the possibility of automated planning. Two important structures of the ear, the facial nerve and the chorda tympani, are difficult to segment with traditional methods because of their size (diameters as small as 1.0 and 0.3 mm, respectively), the lack of contrast with adjacent structures, and large interpatient variations. A multipart, model-based segmentation algorithm is presented in this article that accomplishes automatic segmentation of the facial nerve and chorda tympani. Segmentation results are presented for ten test ears and are compared to manually segmented surfaces. The results show that the maximum error in structure wall localization is ∼2 voxels for the facial nerve and the chorda, demonstrating that the method the authors propose is robust and accurate.
Calcium and calmodulin-dependent protein phosphorylation in rabbit ileum.

Evidence is accumulating to suggest that calcium is a physiological regulator of intestinal electrolyte transport [ 1-3]. Conditions which increase intracellular calcium such as the use of the calcium ionophore A23187 [ 1,2] or exposure to neurohumoral substances such as serotonin [4] or carbachol [ 1 ] cause stimulation of intestinal chloride secretion and/or inhibition ofNa ÷ and C1absorption. To the contrary, conditions which decrease intracellular calcium, such as exposure to the calcium channel blocker verapamil, stimulate Na ÷ and C1absorption [3]. Calmodulin may be involved in these effects since the anti-psychotic drug trifluoperazine (an inhibitor of the calcium-calmodulin complex) inhibited intestinal secretion caused by the calcium ionophore A23187 [5,6]. The intracellular mechanisms by which calcium and calmodulin affect intestinal ion transport are not known. However, as calcium and calmodulin affect phosphorylation and function of specific proteins in several other systems [7,8], phosphorylation is a potential control mechanism for ileal electrolyte transport. These studies are the first demonstration that calcium and calmodulin can cause phosphorylation of intestinal peptides.
A review of conflict detection and resolution modeling methods

A number of methods have been proposed to automate air traffic conflict detection and resolution (CDR), but there has been little cohesive discussion or comparative evaluation of approaches. The paper presents a survey of 68 CDR modeling methods, several of which are currently in use or under operational evaluation. A framework that articulates the basic functions of CDR is used to categorize the models. The taxonomy includes: dimensions of state information (vertical, horizontal, or three-dimensional, 3-D); method of dynamic state propagation (nominal, worst case, or probabilistic); conflict detection threshold; conflict resolution method (prescribed, optimized, force field, or manual); maneuvering dimensions (speed change, lateral, vertical, or combined manoeuvres); and management of multiple aircraft conflicts (pairwise or global). An overview of important considerations for these and other CDR functions is provided, and the current system design process is critiqued.
Quantitative Measurement of Strain in Reinforced Concrete Structures Using Calibrated Optical Fiber Sensors

This paper discusses the use of calibrated, quantitative optical fiber sensors for the internal diagnostics of reinforced concrete structures. Prior optical fiber sensor methods for the monitoring of reinforced concrete specimens and structures during fabrication, laboratory testing and field use first are reviewed. Much of this work has concerned either techniques for embedding optical fibers in concrete without severe damage to the fiber, or the use of qualitative and uncalibrated sensors to infer the general conditions within the concrete. Here we report the use of practical, short gage length relative strain sensors for the measurement and mapping of strain in reinforced concrete beam and crossbeam configurations, and issues in the implementation of absolute rather than relative strain measuring optical fiber sensors. Both types of fiber sensors were attached to rebar reinforcement rods prior to filling with concrete, and were colocated with conventional foil strain gages to allow direct comparison of output signals. By using conventional robust fiber cabling into the specimens, no difficulties due to fiber breakage were encountered.
Link switching: a communication architecture for configurable parallel systems

A novel class of interprocessor communication architectures for configurable systems is introduced. The communication network consists of switch elements connected in a simple, regular topology such as a ring or mesh, with multiple links running between them. Each processor element is connected to one switching element. Multiple links in conjunction with switching make it possible to realize other topologies, even those having higher connectivity. The network provides a bandwidth-connectivity tradeoff, i.e. greater connectivity can be achieved at the expense of lower bandwidth between adjacent nodes. A 1024-node, mesh-connected link switching architecture with 13 links of unit bandwidth between switching elements can be configured as a 10-D binary hypercube with unit bandwidth, a ten-level binary tree with bandwidth 6, or as a 9*9*9 mesh with bandwidth 4. The model unifies ideas from several previous architectures. Switches to implement this architecture have been designed and are being fabricated. >
A Debugging Model with Independent Flaws and Random Masking

A system with a Poisson-distributed number of flaws is undergoing a sequence of trials designed to detect and remove the flaws. On each trial, independently and with probability q, masking occurs that blocks the detection of flaws on that trial. If masking does not occur on a trial then each flaw in the system, independently, is detected with probability p on that trial. Each flaw detected on a trial, independently, is removed with probability r before the next trial. This note derives distributions and measures of quality for this problem.
Personal reflections on an unintentional behavioral scientist

This article consists of some personal reflections on aspects of Janos Aczel's role in the development of mathematical behavioral and social sciences; it is not a new contribution to the literature on functional equations, but rather a recounting of some history.
Cantharidin Poisoning from Ingestion of a "Blister Beetle"

A 10-month-old girl swallowed a beetle of the Meloidae family and developed classical signs of cantharidin toxicity manifested by vomiting, urinary frequency, dysuria, hematuria, proteinuria, glycosuria, elevated blood urea nitrogen, and elevated white blood cell counts. A brief review of the pertinent literature and toxicology is given.
Seven modeling perspectives on teaching and Learning — some interrelations and cognitive effects

Seven categories of models employed in research on teaching and learning in schools are reviewed, demonstrating the general educational metaphors and perspectives associated with each and their cognitive effects. The categories reviewed are called combinatorial models, sampling models, cybernetic models, game models, critical thinking models, ordinary language analysis models, and dynamic structural models. One major cognitive effect is the tendency for those who think primarily in terms of a given perspective to see all classroom phenomena in terms of that perspective and to feel that all other perspectives are inferior in not representing fully what they see from theirs. This means that no critical experiments or new observations are likely to help much in deciding which category of models is most appropriate for a given research need. The desirability of increased tolerance for different perspectives in research and practice is discussed with special reference to teacher education, where the perspective of the teacher candidate may be expected to determine largely how his or her training experience is assimilated. All categories are judged to have considerable scientific potential, because of successful applications within the natural and applied sciences and the degree of precision attained in at least some models. The first category, which is also the most popular (encompassing as it does practically all multiple variable models in education), seems to have the most questionable status when comparisons are made with the conditions in which it has succeeded in the sciences. The last category, dynamic structural models, encounters the greatest difficulty satisfying demands for operational means of testing its models, for the clinical methods required are not easily accessible to the uninitiated, but it offers the hope of more holistic and naturalistic insights into teaching and learning.
Nosocomial septicemia in the cancer patient: The influence of central venous access devices, neutropenia, and type of malignancy

Nosocomial septicemias that occurred over a 32-month period on an inpatient medical oncology service were reviewed. One hundred four episodes of septicemia occurred in 84 patients, 33% with solid tumors and 67% with leukemia or lymphoma. Sixty were primary septicemias, with the remainder being secondary. Of the 118 isolates recovered, 42% were Gram-positive organisms, 45% Gram-negative organisms, and 13% were fungi. Coagulase-negative staphylococci and Escherichia coli were the most common Gram-positive and Gram-negative isolates, respectively. The effect of the type of malignancy, neutropenic status, and presence of a central venous access device (CVAD) on the isolate(s) recovered was studied. Coagulase-negative staphylococci were more commonly isolated from leukemia-lymphoma patients (26% vs. 3%, P less than .01), while Gram-negative isolates (63% vs. 36%, P = .01), specifically Klebsiella species (21% vs. 5%, P = .02), were more common in solid tumor patients. Staphylococcus aureus was isolated more frequently from non-neutropenic patients than from those with neutropenia (19% vs. 4%, P = .02). Gram-positive isolates were more commonly found in patients with a CVAD (51% vs. 29%, P = .03), in particular coagulase-negative staphylococci (29% vs. 2%, P less than .001). In contrast, Gram-negative isolates (62% vs. 34%, especially Klebsiella species (22% vs. 3%, P less than .01) and S. aureus (18% vs. 5%, P = .07) were more commonly isolated from patients with no CVAD. Neither neutropenia nor the presence of a CVAD predisposed to early mortality. Our data suggest that empiric antimicrobial coverage for presumed nosocomial septicemia in the febrile cancer patient should include vancomycin for patients with a CVAD to cover coagulase-negative staphylococci and a cephalosporin for patients with solid tumors, especially those without a CVAD, to cover Klebsiella species.
The reflection of electromagnetic waves by a conducting surface shielded with a plasma layer

The reflection coefficient is calculated for electromagnetic waves incident normally on a flat perfect conductor shielded with a plasma. The profile of the plasma layer is determined by recombination. Two models of plasma decay are studied: an exponential profile corresponding to the first-order recombination (proportional to the plasma density), and an incorporation of the recombination process which is proportional to the density squared. Though the generation of a plasma with a high electric conductivity looks quite possible, the character of plasma decay in the second (more realistic) model is such that a plasma layer in the troposphere would not provide a strong damping of reflected electromagnetic waves.
A Lifespan Analysis of Intraneocortical Connections and Gene Expression in the Mouse II

The mammalian neocortex contains an intricate processing network of multiple sensory and motor areas that allows the animal to engage in complex behaviors. These anatomically and functionally unique areas and their distinct connections arise during early development, through a process termed arealization. Both intrinsic, activity-independent and extrinsic, activity-dependent mechanisms drive arealization, much of which occurs during the areal patterning period (APP) from late embryogenesis to early postnatal life. How areal boundaries and their connections develop and change from infancy to adulthood is not known. Additionally, the adult patterns of sensory and motor ipsilateral intraneocortical connections (INCs) have not been thoroughly characterized in the mouse. In this report and its companion (I), we present the first lifespan analysis of ipsilateral INCs among multiple sensory and motor regions in mouse. We describe the neocortical expression patterns of several developmentally regulated genes that are of central importance to studies investigating the molecular regulation of arealization, from postnatal day (P) 6 to P50. In this study, we correlate the boundaries of gene expression patterns with developing areal boundaries across a lifespan, in order to better understand the nature of gene-areal relationships from early postnatal life to adulthood.
Novel low-kVp beamlet system for choroidal melanoma

Treatment of choroidal melanoma with radiation often involves placement of customized brachytherapy eye-plaques. However, the dosimetric properties inherent in source-based radiotherapy preclude facile dose optimization to critical ocular structures. Consequently, we have constructed a novel system for utilizing small beam low-energy radiation delivery, the Beamlet Low-kVp X-ray, or "BLOKX" system. This technique relies on an isocentric rotational approach to deliver dose to target volumes within the eye, while potentially sparing normal structures. Monte Carlo N-Particle (MCNP) transport code version 5.0(14) was used to simulate photon interaction with normal and tumor tissues within modeled right eye phantoms. Five modeled dome-shaped tumors with a diameter and apical height of 8 mm and 6 mm, respectively, were simulated distinct positions with respect to the macula iteratively. A single fixed 9 × 9 mm2 beamlet, and a comparison COMS protocol plaque containing eight I-125 seeds (apparent activity of 8 mCi) placed on the scleral surface of the eye adjacent to the tumor, were utilized to determine dosimetric parameters at tumor and adjacent tissues. After MCNP simulation, comparison of dose distribution at each of the 5 tumor positions for each modality (BLOKX vs. eye-plaque) was performed. Tumor-base doses ranged from 87.1–102.8 Gy for the BLOKX procedure, and from 335.3–338.6 Gy for the eye-plaque procedure. A reduction of dose of at least 69% to tumor base was noted when using the BLOKX. The BLOKX technique showed a significant reduction of dose, 89.8%, to the macula compared to the episcleral plaque. A minimum 71.0 % decrease in dose to the optic nerve occurred when the BLOKX was used. The BLOKX technique allows more favorable dose distribution in comparison to standard COMS brachytherapy, as simulated using a Monte Carlo iterative mathematical modeling. Future series to determine clinical utility of such an approach are warranted.
Assessing Critical Thinking Outcomes of Dental Hygiene Students Utilizing Virtual Patient Simulation: A Mixed Methods Study

Dental hygiene educators must determine which educational practices best promote critical thinking, a quality necessary to translate knowledge into sound clinical decision making. The aim of this small pilot study was to determine whether virtual patient simulation had an effect on the critical thinking of dental hygiene students. A pretest-posttest design using the Health Science Reasoning Test was used to evaluate the critical thinking skills of senior dental hygiene students at The University of Texas School of Dentistry at Houston Dental Hygiene Program before and after their experience with computer-based patient simulation cases. Additional survey questions sought to identify the students' perceptions of whether the experience had helped develop their critical thinking skills and improved their ability to provide competent patient care. A convenience sample of 31 senior dental hygiene students completed both the pretest and posttest (81.5% of total students in that class); 30 senior dental hygiene students completed the survey on perceptions of the simulation (78.9% response rate). Although the results did not show a significant increase in mean scores, the students reported feeling that the use of virtual patients was an effective teaching method to promote critical thinking, problem-solving, and confidence in the clinical realm. The results of this pilot study may have implications to support the use of virtual patient simulations in dental hygiene education. Future research could include a larger controlled study to validate findings from this study.
Critical Appraisal of Evidence for Improving Gait Speed in People with Multiple Sclerosis: Dalfampridine Versus Gait Training.

Background: Research has not yet compared the treatment effects of dalfampridine with traditional rehabilitation of gait impairments in multiple sclerosis (MS). The purpose of this review was to critically appraise the evidence for dalfampridine and gait training for increasing gait speed in people with MS. Methods: A systematic search of the research literature was conducted. Consideration was given to only randomized controlled trials (RCTs), systematic reviews, and meta-analyses. For selection of gait training studies, only studies involving task-specific gait training interventions and measuring treatment effects on gait speed were considered. Results: Treatment effects on gait speed were extracted from four studies examining the efficacy of dalfampridine and six gait training RCTs. Overall mean increase in gait speed with dalfampridine was 0.07 m/s (95% confidence interval [CI], 0.04–0.09 m/s) compared to 0.06 m/s (95% CI, 0.02–0.10 m/s) for gait training. Among dalfampridine responders (38% of parti...