cssi/SciSciGPT-SciSciNet huggingface dataset:
Making the Most Out of Direct-Access Network Attached Storage

The performance of high-speed network-attached storage applications is often limited by end-system overhead, caused primarily by memory copying and network protocol processing. In this paper, we examine alternative strategies for reducing overhead in such systems. We consider optimizations to remote procedure call (RPC)-based data transfer using either remote direct memory access (RDMA) or network interface support for pre-posting of application receive buffers. We demonstrate that both mechanisms enable file access throughput that saturates a 2Gb/s network link when performing large I/Os on relatively slow, commodity PCs. However, for multi-client workloads dominated by small I/Os, throughput is limited by the per-I/O overhead of processing RPCs in the server. For such workloads, we propose the use of a new network I/O mechanism, Optimistic RDMA (ORDMA). ORDMA is an alternative to RPC that aims to improve server throughput and response time for small I/Os. We measured performance improvements of up to 32% in server throughput and 36% in response time with use of ORDMA in our prototype.
Regulatory rewiring confers serotype-specific hyper-virulence in the human pathogen group A Streptococcus

Phenotypic heterogeneity is commonly observed between isolates of a given pathogen. Epidemiological analyses have identified that some serotypes of the group A Streptococcus (GAS) are non-randomly associated with particular disease manifestations. Here, we present evidence that a contributing factor to the association of serotype M3 GAS isolates with severe invasive infections is the presence of a null mutant allele for the orphan kinase RocA. Through use of RNAseq analysis, we identified that the natural rocA mutation present within M3 isolates leads to the enhanced expression of more than a dozen immunomodulatory virulence factors, enhancing phenotypes such as hemolysis and NAD(+) hydrolysis. Consequently, an M3 GAS isolate survived human phagocytic killing at a level 13-fold higher than a rocA complemented derivative, and was significantly more virulent in a murine bacteremia model of infection. Finally, we identified that RocA functions through the CovR/S two-component system as levels of phosphorylated CovR increase in the presence of functional RocA, and RocA has no regulatory activity following covR or covS mutation. Our data are consistent with RocA interfacing with the CovR/S two-component system, and that the absence of this activity in M3 GAS potentiates the severity of invasive infections caused by isolates of this serotype.
329 ONCE VERSUS TWICE DAILY DOSING OF CEFTAZIDIME IN THE PRETERM INFANT

Ceftazidime (CAZ) pharmacokinetics were studied on day 3 of life in 28 preterm infants who were randomized at birth to receive once or twice daily 25 mg/kg CAZ. Thirteen infants were treated once daily, 15 infants twice daily. Blood samples were collected from an arterial catheter at 0, 0.5, 1, 2, 4, 8, 12h after the CAZ dose in both groups and an additional sample at 24h in the once daily group and analyzed by HPLC-assay. The results were (mean±SD):
Neuronal specific protein NP185 is enriched in nerve endings: Binding characteristics for clathrin light chains, synaptic vesicles, and synaptosomal plasma membrane

The neuronal specific protein NP185, found associated with brain clathrin-coated vesicles, formed a complex with unphosphorylated, but not with phosphorylated, clathrin light chains. The NP185-clathrin light chain complex was associated with casein kinase II activity, which, in the presence of polylysine, phosphorylated clathrin light chain b but not the NP185. The dissociation of this complex with 50% ethylene glycol pH 11.5 suggests that NP185 binds to hydrophobic domains of clathrin light chains. When NP185 molecules were retained by monoclonal antibody-linked Sepharose beads, they bound synaptic vesicles, decoated vesicles and synaptosomal plasma membrane. Immunohistochemistry on mouse cerebellar tissue sections using 8G8, a monoclonal antibody raised against NP185, showed neuronal specific labeling closely following synaptic distribution. In immunoblots, NP185 shares similar epitopes to those detected in another assembly polypeptide, AP-180, an indication that both proteins are identical. It appears that NP185 plays a specific role in nerve ending functions through its ability to induce clathrin to polymerize into cages, its interaction with synaptic vesicles, with the plasma membrane and with clathrin coat components.
IDENTIFIABILITY OF PARAMETERS IN ITEM RESPONSE MODELS WITH UNCONSTRAINED ABILITY DISTRIBUTIONS

If a parametric model for the ability distribution is not assumed, then the customary two-parameter and three-parameter logistic models for item response analysis present identifiability problems not encountered with the Rasch model. These problems impose substantial restrictions on possible models for ability distributions.
Geological nitrogen cycle and atmospheric N2 over Phanerozoic time

Using the average nitrogen/carbon ratio (N/C) of sedimentary organic matter, coal, and volcanic/metamorphic gases, existing models of the carbon cycle have been used to calculate the fluxes of nitrogen to and from the atmosphere via the weathering, burial, and metamorphic/volcanic decomposition of organic matter. Results indicate no appreciable change, less than one percent of that present, in the mass of atmospheric N 2 over Phanerozoic time. This is in sharp contrast to atmospheric O 2 , which shows notable variations. Variation of the mass of O 2 , but not that of N 2 , must have led to variation in total atmospheric pressure with time. Results are not altered by considering N/C ratios ten times higher than the average for sedimentary rocks nor by considering nitrogen release from silicate weathering. The residence time of N 2 in the atmosphere, relative to exchange with and storage in crustal rocks, is estimated to be about one billion years.
Power Transition Extended

Regions of War and Peace. By Douglas Lemke. Cambridge: Cambridge University Press, 2002. 252 pp., $65.00 cloth (ISBN: 0-521-80985-1), $23.00 paper (ISBN: 0-521-00772-0). Before the current popularity of strategic models, the study of world politics in the United States after World War II was dominated by structural approaches. Structural arguments took the centrality of the major powers as determinants of the international system as a given. Indeed, relative capabilities among the major powers supposedly held the key to international stability (Waltz 1979; Thompson 1988). The dominant parity school of thought held that the international system was stable when major power capabilities were in rough equivalence, with stability being the absence of system-changing major power war (Morgenthau 1948; Waltz 1959, 1979). Even though parity scholars held much sway in academic circles, they did not go unchallenged. At the end of the 1950s, A. F. K. Organski developed his power transition theory, which held, contrary to the parity argument, that a preponderance of capabilities in the hands of one dominant power is coincident with system stability, and that movements toward rough equivalence lead to war (Organski 1958; Organski and Kugler 1980; Kugler and Organski 1989). The power transition theory, however, is not just another structural approach to international stability. It also speaks to issues of political and economic development, and even state strategy. Indeed, whereas parity scholars talk about system change resulting from the fluidity of alliance patterns, Organski and his followers look domestically at the major states themselves as the source of system change. Although the economic potential for growth exists in most societies, the political organization to harness that potential varies across both time and space. The states that become better organized politically can better harness, direct, and guide economic production, which creates growth. Growth in turn creates power or enhanced …
Coefficients of Digestibility and Caloric Diet of Rodents in the Northern Great Basin Desert

In desert ecosystems small rodents are major components of the vertebrate fauna and they likely influence greatly the distribution and abundance of certain producers. In addition to the direct influence on producers, small mammals may also regulate the cycling of nutrients and the transfer of energy. In describing the flow of energy through a species, it is important to determine how effectively the species digests its diet and to quantify the caloric content of its natural diet. This study determined the digestibility coefficients and caloric diet of eight common species of rodents in the northern Great Basin desert. The species are: Great Basin pocket mouse (Perognathus parvus), deer mouse (Peromyscus maniculatus), northern grasshopper mouse (Onychomys leucogaster), western harvest mouse (Reithrodontomys megalotis), Ord's kangaroo rat (Dipodomys ordii), Chisel-toothed kangaroo rat (Dipodomys microps), least chipmunk (Eutamias minimus), and Townsend's ground squirrel (Spermophilus townsendii).
Drug-induced esophagitis simulating esophageal carcinoma

Drug-induced esophagitis is an infrequently diagnosed but important cause of esophagitis. Damage to the esophageal mucosa can be severe and cause esophageal strictures that may appear malignant by radiographic and endoscopic criteria. The diagnosis requires a high index of suspicion and a careful review of the patient's drug history. Cessation of implicated drugs permits resolution of esophageal inflammation. Two patients with drug-induced esophagitis simulating esophageal carcinoma are presented.
Analysis of individual acidic organelles by capillary electrophoresis with laser-induced fluorescence detection facilitated by the endocytosis of fluorescently labeled microspheres.

Submicrometer-sized fluorescent microspheres were loaded into the acidic organelles of NS-1 mouse myeloma cells via endocytosis. Confocal microscopy imaging showed that microspheres colocalized nearly perfectly with LysoTracker Red, a probe that stains acidic organelles. Unlike LysoTracker dyes that seem to leak from acidic organelles upon cell disruption, microspheres are retained within these organelles, facilitating their analysis following isolation. Using capillary electrophoresis (CE) with laser-induced fluorescence detection (LIF), the electrophoretic mobilities of acidic organelles were individually calculated and fluorescence intensities individually measured. When cells were incubated for sufficient time to allow for endocytosis (48 h) with 3.9 × 103 microspheres/cell, replicate CE-LIF analyses of the corresponding isolated fraction indicated a dramatic increase in the number of detected events (n = 1990 ± 234) and in the overall fluorescence intensity of the individual events (0.38 ± 0.01 RFU; ...
Transonic laminar boundary layers with surface curvature

The effect of surface curvature (both longitudinal and transverse) and the associated pressure gradient across the flow is investigated analytically for a laminar boundary layer subjected to pressure gradients along the flow. Property variation which results from heat transfer and compressibility is taken into account. Numerical solutions of the boundary layer equations are obtained for locally similar sonic flow through the throat of a nozzle for a range of flow conditions and for various shaped nozzle surfaces with different amounts of wall cooling. A few solutions were also obtained for the analogous flow around the shoulder of a flat-faced body in a supersonic flow. The effect of various parameters that arise in the equations upon application of the Levy-Mangler transformation are investigated and discussed with respect to their influence on the velocity and total enthalpy profiles and the corresponding profile slopes at the surface to which the shear stress and heat transfer are related. An important finding is that at throat Reynolds numbers less than 100,000 the heat transfer parameter at a nozzle throat decreases as the throat radius of curvature decreases.
Mixed-Integer Multiobjective Process Planning under Uncertainty

This paper presents a methodology for addressing investment planning in the process industry using a mixed-integer multiobjective approach. The classic single-objective MILP stochastic model is treated as a multiobjective programming problem by the use of multiparametric decomposition. To ensure computation of the entire efficient frontier, use of the augmented Tchebycheff algorithm is proposed. This allows for the decision making to be based on the suggested solutions and their neighbor solutions, a feature that other stochastic programming models fail to capture. An iterative procedure is proposed to help the decision maker visualize the efficient solutions in the multidimensional space and facilitate the assessment of the economical risk of the project.
Nerve growth factor rapidly regulates VGF gene transcription through cycloheximide sensitive and insensitive pathways.

Nerve growth factor (NGF) initiates and maintains a regulatory cascade, involving gene induction, which results in the neuronal differentiation of PC12 cells. The VGF gene encodes one of the most rapidly induced neuronal mRNAs identified in NGF-treated PC12 cells (Science, 229 (1985) 393–395; Mol. Cell Biol., 11 (1991) 2335-2349]. In this communication we show that NGF-treatment for 60–90 min maximally increases VGF gene transcription by 12- to 14-fold. VGF mRNA half-life was found to substantially dccrease in PC12 cells treated with NGF for 9–25 h. Partial inhibition of VGF gene transcription and superinduction of cytoplasmic VGF mRNA levels in the presence of both NGF and cycloheximide suggests that the VGF gene may be regulated through multiple pathways, some of which can be activated in the presence of protein synthesis inhibitors as are the immediate early genes, while others require newly synthesized proteins.
Electrophysiological responsiveness to isoproterenol in rat hippocampal slices correlates with changes in β-adrenergic receptor density induced by chronic morphine treatment

Abstract The effects of chronic morphine treatment and morphine withdrawal on β-adrenergic receptor density and electrophysiological responsiveness in rat hippocampus were examined. Chronic treatment of rats with morphine for 14 days resulted in a 19% increase in the number of β-adrenergic receptors in hippocampus, as measured by the binding of the specific antagonist [ 3 H]dihydroalprenolol (DHA). In comparison, the number of specific binding sites for [ 3 H]DHA was decreased 27% in hippocampus in morphine-withdrawn animals, compared to saline-treated controls. These alterations in β-adrenergic receptor density were not accompanied by a significant change in the dissociation constant ( K d ) for [ 3 H]DHA or in the inhibitory constants ( K i ) for the displacement of the [ 3 H]-antagonist by either norepinephrine or isoproterenol. Electrophysiological experiments in the in vitro hippocampal slice preparation revealed that responses to threshold as well as maximal concentrations of isoproterenol were significantly enhanced in morphine-dependent animals, compared to controls, whereas electrophysiological responsiveness to maximal concentrations of isoproterenol was decreased in slices from morphine-withdrawn rats. The results of this study indicate that β-adrenergic receptors in hippocampus are up-regulated during the development of morphine dependence and down-regulated during opiate withdrawal. These changes in hippocampal β-adrenergic receptor density are likely to be of functional relevance since they are manifested in a corresponding increase and decrease, respectively, in electrophysiological responsiveness to an exogenously administered β-adrenergic receptor agonist.
In vitro study of phase resetting and phase locking in a time-comparison circuit in the electric fish, Eigenmannia

The electric fish Eigenmannia generates on oscillating weak electric field. The amplitude and timing information of this electric field is perceived by electroreceptors distributed on its skin. The pathway of timing information, consisting of spherical cells and giant cells, was studied in an in vitro preparation. The giant cells were identified to be endogenous oscillators and thus have the functional advantage of phase locking more easily to a periodic stimulus with a frequency in the range of the intrinsic frequency. Their spontaneous rhythmic activity was perturbed by delivering excitatory single pulses or periodic pulses via their synaptic inputs. The regular and irregular dynamics produced by periodic stimulation were discussed in the context of a mathematical analysis of the response to single pulses. Ambiguous representations of the timing of the stimulus pulse were observed and could be related to this analysis. Some spontaneously firing cells could be silenced with periodic excitatory stimulation in a narrow frequency and amplitude range. Some irregularly firing cells continued to fire periodically for several seconds after phase locking to a periodic stimulus. This study is the first description of an endogenous oscillator in a system devoted to the precise timing of sensory events.
Sea beam sidelobe interference cancellation

The Sea Beam multibeam bathymetric system is in operation aboard research vessels worldwide. While it has contributed greatly in advancing the understanding of the deep-sea floor, several types of bathymetric artifacts have been identified in its contoured output which could be mistaken for sea floor structure. Among those, the "tunnel" effect results from sidelobe interference caused by the near specular return and is most prominent when the sea floor is relatively flat. It is characterized by a trough in the bottom profile produced by Sea Beam. It will be shown that this type of interference can be greatly reduced or eliminated through an adaptive filtering scheme, pending a minor modification of the Sea Beam data acquisition system. The noise-cancelling configuration of the adaptive least-squares lattice filter will be used to process simulated Sea Beam data obtained through REVGEN, a high-fidelity sonar system simulation program.
Chemical stimulation of oospore formation in Phytophthora capsici.

Oospore distribution patterns in pairings between compatible isolates of Phytophthora capsici suggested mutual induction of oospore formation. Oogonia and oospores formed near the A2 colony were smaller than those developing near the A' colony, suggesting that the smaller bodies were A2 products and the larger bodies were formed by A'. This interpretation was confirmed in pairings physically separated by polycarbonate membranes. Significantly more oospores were produced in synthetic medium containing Difco Bacto agar as compared to Difco Noble agar, Difco purified agar or SeaKem agarose.
The Pathophysiology of the Onset of Morning Cardiovascular Events

Evidence obtained over the past decade indicates that myocardial infarction (MI) and sudden death are not random events but rather, in many cases, may be triggered by the daily activities of the subject. The importance of physical or mental stresses as triggers is suggested by the parallel morning increased onsets of MI, sudden cardiac death, and stroke. Unstable angina and MI are usually precipitated by thrombus formation over a disrupted plaque that causes partial or complete obstruction of coronary artery blood flow. This process may be caused by physiologic factors that lead to rupture of a vulnerable plaque and subsequent thrombosis. Beta-blockers and aspirin, which can diminish these physiologic processes, have been shown to blunt or abolish the morning peak of onset of acute MI. It is hypothesized that occlusive coronary thrombosis occurs when an atherosclerotic plaque becomes vulnerable to rupture, and mental or physical stress causes the plaque to rupture. Increases in coagulability or vasoconstriction triggered by daily activities may also contribute to complete occlusion of the coronary artery lumen. Recognition of the circadian variation of the onset of acute cardiovascular disease suggests the need for pharmacologic protection of patients during the vulnerable periods and provides clues to the mechanism of disease onset, the investigation of which may lead to improved methods of prevention.
Evaluating biofield treatments in a cell culture model of oxidative stress.

Objective To test whether healing treatments by biofield practitioners can protect normal human brain cells against cell death induced by oxidative stress. Design Cultured human brain cells were exposed to increasing concentrations of hydrogen peroxide and cell death was quantified by computerized time-lapse microscopy. Biofield treatments were delivered to cells from a short distance in 24 independent experiments. Six highly experienced biofield practitioners each participated, all with exceptional reputations within their respective communities (4 independent experiments each). An equal number of control experiments involving no healing intervention were conducted to provide a measure of intrinsic variability of the experimental system. Experiments were conducted with blinding applied to each of the scientists and randomized sample assignment. Intervention Healing treatments were delivered to cells from a short distance by a single practitioner, before and after exposure to hydrogen peroxide, for a total of 30 minutes. Outcome Measure Cell death was quantified over a 4-hour period following experimental treatments. Results We found no significant difference in cell death rates between treatment and control groups.
Correction Factor for Continuous Monitoring of Wood Smoke Fine Particulate Matter

ABSTRACTThe US Environmental Protection Agency (EPA) has designated a handful of instruments as Federal Reference or Federal Equivalency Methods (FRM and FEM, respectively) for the monitoring of fine particulate matter (PM2.5). More commonly used for indoor exposure assessment studies are optical scanning devices such as the DustTrak (TSI) due to their portability and affordability. It is recommended by the manufacturer of these instruments that a “correction factor” be applied when assessing source-specific conditions. In this study, DustTraks were collocated with multiple samplers in various environments in an effort to establish an indoor, wood smoke-source specific correction factor. The DustTrak was found to report PM2.5 levels on average 1.6 times higher than a filter based method in two indoor sampling programs. The DustTrak also reported indoor PM2.5 concentrations 1.7 times higher than a FRM sampler during a regional forest fire event. These real-world scenarios give a correction factor within a reasonable range of the results of a controlled laboratory experiment in which DustTraks reported PM2.5 approximately 2 times higher than a FEM. Our indoor wood smoke-specific correction factor of 1.65 will allow for DustTraks to be confidently used in quantifying PM2.5 exposures within indoor environments predominantly impacted by wood smoke.
Inheritance of optimal foraging behaviour in Columbian ground squirrels

I examined the potential inheritance of the ability of Columbian ground squirrels (Spermophilus columbianus) to select an optimal diet. I calculated the diet that would maximize daily energy intake for each of 21 adult females and their litters, using a linear programming optimization model for each individual. The absolute value of the difference between an individual's predicted optimal diet and observed diet (deviation from an optimal diet) was used as a measure of an individual's foraging ability. The foraging ability of individuals was consistent over time and in different foraging environments, so I considered foraging ability to be a potentially heritable trait. Inheritance was determined from correlations of mother and offspring foraging ability. I experimentally removed some mothers just as they weaned their offspring so that offspring could not be influenced by their mother while learning to forage, while leaving the other mothers to raise their litters normally. In both cases, offspring strongly resembled their mother in foraging ability. However, offspring with mothers absent exhibited significantly larger deviations from their optimal diet. Offspring with mothers absent appeared to imitate their mother's diet during lactation, and this tendency partially explained their greater deviation. Consequently, offspring appear to inherit the ability to forage optimally from their mother, perhaps through observational learning or imitation. There may also be a genetic basis to foraging ability, but uncontrolled maternal effects in the experiment prevent a proper test for it.
Electric Properties of Ice Fog Crystals

Abstract Electric properties of ice fog crystals were studied using uniform and nonuniform electric-fields. It was observed that natural and artificial ice fog crystals had no significant net charge. An upper bound for the net charges was derived. The observations are discussed in relation to the induced dipole moment and Weyl's model of ice crystals.
Secure topology discovery through network-wide clock synchronization

Clock synchronization is a fundamental service for many applications in wireless sensor networks. Because of its critical importance, several protocols have been proposed to achieve clock synchronization. However, most of them are not designed to work in adversarial environments, where security attacks occur. In particular, a man-in-the-middle attack, where the attacker tampers with the properties of a link, could prevent the proper operation of the clock synchronization protocol, therefore affecting every application that relies on the clock synchronization service. We present a secure network-wide clock synchronization protocol which also allows the nodes to securely discover the network topology by detecting and isolating links that behave inconsistently. This protocol is based on detecting attacks using timing information alone under certain conditions. We have developed an implementation of this protocol where we have shown that any inconsistent link found in the network is effectively eliminated.
Arbuscular mycorrhizal fungal isolate effectiveness on growth and root colonization of Panicum virgatum in acidic soil

Abstract Arbuscular mycorrhizal fungi (AMF) can enhance plant ability to grow and withstand acidic soil induced stresses. Panicum virgatum L. (switchgrass) was grown in pH Ca 4 and 5 (soil:10 mM CaCl 2 , 1:1) soil (typic Hapludult) inoculated with eight isolates of AMF [ Glomus ( G .) clarum , G. diaphanum , G. etunicatum , G. intraradices , Gigaspora ( Gi .) albida , Gi. margarita , Gi. rosea and Acaulospora ( A .) morrowiae ] to determine the effects of these isolates on plant growth and root colonization. Compared to nonmycorrhizal (nonAMF) plants, mycorrhizal (AMF) plants had as high as 52-fold increases in dry matter (DM) in pH Ca 4 soil and as high as 26-fold increases in DM in pH Ca 5 soil; G. clarum and G. diaphanum plants had the highest DM and Gi. rosea plants had the lowest DM. The AMF plants grown in pH Ca 4 soil had higher DM than in pH Ca 5 soil. Root DM decreased more than shoot DM for plants grown in pH Ca 5 compared to pH Ca 4 soil, which was reflected in shoot-to-root DM ratio changes. Total root length (RL) was similar for plants grown in pH Ca 4 and 5 soil and varied considerably depending on AMF isolate. Specific RL was higher for AMF plants grown in pH Ca 5 than in pH Ca 4 soil. Root colonization [determined as vesicles or arbuscules in root cells (VA), roots with hyphal infections (HI) and total colonization (VA or HI)] varied extensively with AMF isolate. Although percentage root colonization was not directly related to amount of DM, good enhancement of DM did not occur unless total colonization was >20%. Some AMF isolates were highly effective in overcoming acidic soil constraints and good growth of switchgrass in acidic soil may depend on root-AMF symbiosis.
Cross-country truck drivers: A vulnerable population

Abstract The identification of vulnerable populations has received considerable attention in recent years. Truck drivers can be identified as one of these vulnerable populations. Nursing's role in the improvement of the issues that make truck drivers vulnerable includes providing direct services and influencing policy changes through action and research.
Suprascapular nerve entrapment isolated to the spinoglenoid notch: surgical technique and results of open decompression

Background Entrapment of the suprascapular nerve (SSN) at the spinoglenoid notch (SGN) specifically affects the infraspinatus, and isolated external rotation (ER) weakness can result. We describe the technique of open SSN decompression at the SGN for infraspinatus involvement and report the results of a consecutive series. Materials and methods Twenty-nine shoulders underwent SSN decompression at the SGN. The mean age was 44 years (range, 15-69 years), and the mean follow-up was 4.3 years (range, 1-7 years). On manual muscle testing, ER strength was abnormal in all patients: 2/5 in 3, 3/5 in 21, and 4/5 in 5. The mean preoperative American Shoulder and Elbow Surgeons (ASES) score was 48 (range, 23-83). Atrophy of the infraspinatus was visible or palpable in 72% of shoulders. Magnetic resonance imaging showed ganglion cysts at the SGN in only 20.7% of shoulders. Results Of the patients, 19 (66%) regained full ER strength, 9 (31%) improved to 4/5, and 1 (3%) had ER strength of 3/5. The mean ASES score improved to 75 (range, 60-100) (P Discussion A ganglion cyst is not necessary to produce SSN compression at the SGN. SSN compression at the SGN can present as an isolated entity or can occur in conjunction with rotator cuff pathology or a ganglion cyst. An index of suspicion, physical examination, magnetic resonance imaging, and electromyography confirm the diagnosis. The described operative approach detaches no muscle and allows rapid recovery, and in all cases, ER strength improved to normal or by 1 full grade.
Prostate-specific antigen: questions often asked.

(1990). Prostate-Specific Antigen: Questions Often Asked. Cancer Investigation: Vol. 8, No. 1, pp. 27-37.
Corrugated-Bellows Vacuum Chamber for Fast-Cycling Synchrotrons

Corrugated metal bellows of several meters length are a satisfactory and very inexpensive vacuum chamber for new or existing fast-cycling synchrotrons.
WE-E-18A-09: Application of a Channelized Hotelling Observer Model to Evaluate Angiographic Imaging Equipment

Purpose: To develop and apply an observer model to objectively evaluate and compare the performance of different angiographic imaging equipment and acquisition variables. Methods: Image Acquisition— Iodine-based phantoms were created with target diameters: 0.5, 1, 2, and 4 mm. The phantoms were imaged using both planes of a bi-plane angiography system with detector pixel dimensions 0.1542 mm2 and 0.1842 mm2, respectively. All four phantoms were imaged with magnification factors 1.5, 1.25 and 1 and with the large and small focal spots. Phantom position and the dose per frame (0.12– 0.24 μ Gy/frame) were varied for a single phantom size, magnification and focal spot. Observer Model— For each experimental condition, 1200 signal-present and signal-absent images were acquired and a detectability index (d') was calculated with a Gabor-channelized Hotelling observer (CHO) model. Detectability indices were evaluated as a function of dose, phantom size, and magnification. The model was then applied to compare d' of the two imaging planes and focal spots. Uncertainty in d' was estimated by bootstrapping the data and by examining the shift-variance of systems. Results: Detectability indices varied linearly with magnification and the square root of dose. For the 2 and 4 mm phantoms, d' varied linearly with diameter. For the 0.5 and 1 mm phantoms, d' expectedly deviated from this linear relationship due to substantial detector and focal spot blurring of the phantoms. The small focal spot yielded up to 50% greater d' values than the large focal spot. For the two detectors, differences in d' did not exceed the estimated ∼7% error. Conclusions: The detectability indices predictably scaled with dose, diameter, magnification, and focal spot size and serve to validate the model. Results demonstrate statistically similar target detectability for both investigated detectors, despite differences in pixel dimensions. This CHO model provides a framework to evaluate angiographic system performance.
The “muscular variant” of Pompe disease: Clinical, biochemical and histologic characteristics

We report on a 2-yr-old boy with progressive muscular weakness and respiratory failure. There was no clinical evidence of heart muscle involvement. Autopsy showed marked intralysosomal glycogen deposition in skeletal muscle and liver with no histological evidence of glycogen deposition in cardiac muscle. The activity of the lysosomal enzyme alpha-1,4-glucosidase was deficient in skin fibroblasts, skeletal muscle, cardiac muscle, and liver; however, the enzymatic activity in peripheral blood leukocytes was in the low normal range. The child's mother had normal enzymatic activity in leukocytes but heterozygote levels in skin fibroblasts.
Global existence theory for a generalized Ginzburg-Landau equation

The authors obtain sufficient conditions for the global existence of solutions of a Ginzburg-Landau equation with additional fifth-order terms and cubic terms containing spatial derivatives.
Single bottleneck systems with proportional expected yields and rigid demand

Abstract This study considers single bottleneck systems: multistage production systems where all setup costs except one are zero. The stage with non-zero setup cost is defined to be the bottleneck (BN). Production is in lots and demand needs to be satisfied in its entirety. The expected yield (number of good units) at each stage is proportional to the lot size and only good items may proceed from one stage to another. We reveal several general features of the optimal policy and discuss some specific yields in detail. In particular it is shown that if units are processed one-by-one on the non-BNs, the optimal lotsizing problem can be reduced to the problem of optimally lotsizing a single-stage ‘equivalent machine’. Then, if the BN has Binomial yeild, the ‘equivalent machine’ itself has Binomial yields. Also, examples are given which demonstrate the non-intuitive structure of the optimal policy.
Belkoranic hill ciphering

Hill ciphering can be adapted to produce a coherent ciphertext message for any given plaintext message. This is done by finding a matrix Q that will transform using modular arithmetic, for example, ‘cat’ into ‘dog,’ and ‘dog’ back into ‘cat’. The procedure for choosing the elements of Q involves solving sets of linear Diophantine equations. The existence of Q for any (x, y) pair of plaintext/ciphertext messages is guaranteed as long as the conditions for application of Cramer's Rule are satisfied by the Diophantine equations. The interest of Belkoranic Hill Ciphering lies in its innocent-looking coherent ciphertext.
Predicting school performance of preschool children from parent reports

Parents of 391 preschool children ages 49 to 64 months completed a brief developmental inventory as part of a preschool screening program operated by an urban school district. The 28-item developmental inventory assessed adaptive behavior and language development. In addition, preschool children were administered the Minneapolis Preschool Screening Instrument. Teacher ratings of kindergarten performance the following year provided criterion data to validate the screening measures. Correlations with the overall teacher rating [the mean of nine ratings] were .40 for the adaptive behavior scale and .57 for the language scale. Validity figures for the developmental inventory were significantly higher for low SES than for high SES children, for older children [57 to 64 months] than for younger children [49 to 56 months], and for firstborn children than for younger siblings. No effects were found by sex. While a positive relationship between parent reports of developmental functioning and early school performance was clearly established, validity levels did not justify use of parent information as a sole source of preschool screening information.
Government statistics: the conflict between research and privacy.

The production of social statistics has been challenged in certain West European nations by the “privacy issue.” Privacy advocates contend thatcomputerized data files containing information about individuals endanger personal privacy and other civil liberties. The privacy issue has taken two forms: anti-census campaigns and data protection systems. Although those responsible for statistical data have traditionally safeguarded their records, they areoften drawn into this issue. Increasingly, they have had to deal with the sociopolitical environment through legislative liaisons, lawyers, and advertising agencies. They have also had to revise data collection and processing procedures. In some situations, they have had to suspend censuses and surveys.
Hippocampal protein kinase C activity is reduced in poor spatial learners

Activation of protein kinase C (PKC) via neurotransmitter coupling processes has been associated with long-term potentiation (LTP) or classical conditioning, but whether natural variation in PKC activity affects learning performance remains to be determined. Inbred strains of mice differ in their ability to exhibit spatial reference memory as measured by the Morris water task. C57BL/6Ibg (C57) mice perform the task better than DBA/2Ibg (DBA) mice, which show relatively little spatial preference. Hippocampal PKC activity extracted from the particulate fraction was lower in DBA mice than in C57 mice. To examine the potential relationship of PKC activity with spatial learning performance, 11 C57BL/6J x DBA/2J recombinant inbred strains (BXD RIs) were trained in the place learning version of the Morris water task. Cortical and hippocampal PKC activities were measured. Variation in spatial learning performance and PKC activity from cortex and hippocampus was observed. A positive significant correlation was observed between measures of spatial learning accuracy and hippocampal PKC in these strains. No correlation was observed between spatial learning accuracy and cortical PKC activity. These data suggest that animals with lower hippocampal PKC activity may have problems performing spatial reference memory tasks with the same degree of accuracy as those with higher hippocampal PKC activity.
Identification of Some Volatile Compounds Related to the Flavor of Milk and Cream

Summary A low temperature-reduced pressure distillation technique was employed to obtain a total distillate considered to be representative of milk flavor. The carbonyl compounds contained in the aqueous fraction were separated and identified as their 2,4-dinitrophenylhydrazones by paper chromatography, column partition chromatography, ultra-violet spectroscopy, and melting point determinations. Data thus obtained established the presence of formaldehyde, acetaldehyde, acetone, butanone, pentanone-2, and hexanone-2 in milk and cream and presented tentative evidence for heptanone-2 in cream. Quantitative analysis of these individual carbonyl compounds also was performed. The volatile compounds obtained from liquid nitrogen trapping of milk and cream were also investigated. These volatiles were fractionated by gas chromatography and several of the eluted components trapped in liquid nitrogen for mass spectral analysis. The mass spectra data in conjunction with retention times established the identity of ethyl ether, methyl sulfide, acetone, butanone, ethanol, chloroform, acetonitrile, and ethylene chloride. Evidence also was obtained for the presence of a waxy, nut-like odor which is highly characteristic of cream. Its identification awaits further study.
Hirschsprung's disease in a young adult: report of a case and review of the literature

Hirschsprung's disease (HD) in adults is rare and often undiagnosed or misdiagnosed. We report a case of HD in a 26-year-old woman who had a history of chronic constipation that required laxatives and enemas since early childhood. She developed severe intestinal obstruction and presented to the emergency department with significant abdominal distension. A computed tomographic scan confirmed significant fecal loading of the entire colon and rectum. An anal manometry revealed lack of normal rectoanal inhibitory reflex. A rectal biopsy showed hypoganglionic anorectum, suspicious for HD. Because of the severe fecal retention that was refractory to conservative management, total proctocolectomy with ileal pouch-anal anastomosis was performed. The entire colon showed massive dilatation and marked wall thickening. Histologic examination showed absence of ganglion cells in submucosal (Meissner's) and myenteric (Auerbach's) plexuses in the distal rectum. A diagnosis of adult HD was made. Her postoperative course was uneventful with complete resolution of the symptoms. Hirschsprung's disease should be considered in adults who have long-standing and refractory constipation.
Pulsation artifact in short TR MR imaging and angiography: Exacerbation with signal averaging

Averaging the signals from more than one excitation per phase-encoding view increases the signal-to-noise ratio and, in conventional spin-echo magnetic resonance imaging, reduces most motion artifacts. To determine the effects of signal averaging on two-dimensional gradient-echo images, acquisitions with different TRs and with no averaging versus multiple-signal averaging were compared in a pulsatile flow phantom and the human abdominal aorta. Intraview (each view repeated before changing the phase-encoding value) and interview (obtaining all views sequentially and then repeating the entire set) averaging methods were used. Pulsation artifacts were present on all images of the flow phantom and the aorta. Intraview signal averaging, the method most commonly used, exacerbated rather than ameliorated pulsation artifacts with short TR sequences. Pulsation artifacts on two-dimensional images obtained with a short TR can be minimized by completing the acquisition as rapidly as possible, avoiding signal averaging. If signal averaging is used for short TR images, it should be interview averaging.
1,3‐Dichloro‐5‐(dimethylamino)borazine

In the crystal structure of the title compound, C2H9B3Cl2N4, the asymmetric unit consists of two independent mol­ecules. Both mol­ecules show a planar conformation and are essentially identical in shape and size, differing mainly in their packing behavior.
Analysis of doramectin in the serum of repeatedly treated pastured cattle used to predict the probability of cattle fever ticks (Acari: Ixodidae) feeding to repletion

Analysis of doramectin concentration in blood serum of pastured cattle injected repeatedly (12 treatments) at two different dosage rates and 28-day intervals throughout the year was used to predict the probability that cattle fever ticks could successfully feed to repletion during the interval between any two consecutive treatments. Treatment at ~270 μg/kg indicated that serum doramectin concentration dropped below the baseline concentration estimated for tick survival (8 ppb) in 7 of the 12 treatments. However, the longest period between any two treatments during which the doramectin concentration remained below the 8 ppb baseline level for successful tick feeding was 15 days, making it virtually impossible for any ticks to reach ovipositional status prior to a subsequent treatment. At a dosage rate of ~540 μg/kg, the concentration dropped below the baseline tick survival level (8 ppb) only once, following the initial treatment, and the duration during which the concentration remained below the baseline level prior to the subsequent treatment was only 6 days. Thus, at the high dosage rate results indicated, with absolute certainty, that no ticks could successfully feed to repletion between any two consecutive treatments. Based on the data obtained in the study it was concluded that analysis of doramectin concentration in serum of treated animals would be a reliable predictor for assessing the probability that ticks could successfully develop to repletion. More importantly, results demonstrated that the trial policy, instituted by the Cattle Fever Tick Eradication Program, of repeatedly treating cattle with doramectin injections at 25–28 day intervals for eliminating cattle fever ticks would produce little or no risk of any viable ticks developing to repletion and re-infesting the field between treatment applications.
Density of states, electron-transport mechanisms, and chemical potentials in the presence of inelastic processes.

We present a formulation for the estimation of the density of states for quantum structures, such as the quantum wire and the single- and multiple-barrier structures. Our formulation is based on the quantum kinetic approach as opposed to the single-particle approach; therefore, the model inherently accounts for the exclusion principle and incorporates phase randomizing and/or inelastic collisions. Also in this paper, we propose a physically meaningful decomposition of the density of states for left- and right-moving electrons. The total and the decomposed densities of states are then used to define chemical potentials that may be measured by the symmetric and asymmetric voltage probes. The present approach eliminates some unphysical features reported in earlier work and enables us to propose an alternative, but equivalent, expression to the well-known Tsu-Esaki equation for the tunneling current. In our transport equations, the usual transmission coefficients are not needed; instead, we introduce the concept of a state-current density that may be used to describe the current through tunneling barrier structures. Moreover, we use this concept of the state-current density to comment on the coherent and the sequential tunneling mechanisms for double-barrier structures.
Locate mode processing for hand-held land mine detection

Landmine detection using hand-held GPR unit has two modes of operation: search mode and locate mode. Search mode generates an initial detection at a suspected location and locate mode affirms that the suspected location contains a land mine. Search mode requires causal processing and has a high false alarm rate. Locate mode allows the operator to interrogate the suspected location to eliminate false alarms and does not require causal processing. This paper proposes an algorithm for locate mode processing. The proposed method uses the consistency of detection as well as the shape of detection peaks over several sweeps to improve the detection accuracy. The proposed algorithm was examined through a data set collected at a test site, and was compared with the performance when taking the maximum of detection values over several sweeps. Experimental results showed that the proposed method reduces the probability of false alarm by more than 70% at 100% correct detection rate.