cssi/SciSciGPT-SciSciNet huggingface dataset:
Twenty years in the hole.

I am busy counting down the days. In 1 week, I will have completed 20 years as an emergency physician. There were times I would not have believed it would happen. Oh, I have been seduced through the years by the lady with lipstick, the upscale urgent care, the liposuction clinic, the work comp clinic, the administrative office job. But, though I was tempted, I stuck with the girl I took to the dance. Perhaps this is because I am stupid. This is probably part of it. Had I been wiser, by now I might be the king of my own ER Empire, or botox spa. Perhaps I am just lazy. This is also possible. But, in the end, I think I just liked my first girlfriend the best. Twenty years ago, I had not heard of propofol and could not have imagined rolling an ultrasonography machine to the bedside. Twenty years ago, in my youth of nasotracheal intubations, I carried a syringe of lidocaine in my front pocket. This was to anesthetize the cords. I had forgotten all about this until I ran across an old photograph of myself at the University Hospital in Louisville. There it was, my “baton,” as we called it. We would pass it off, shift to shift, as a relay sprinter might. On my last night in residency, the nurses cut off my scrubs, a kind of ritual to prepare me for the “real world.” I have a photo of this too. And on that night, Tom Buckley, my best friend and coresident, took off his residency shoes, shiny white Navy shoes, and hung them on a nail in the ED. They stayed there for several years.
Performance of computer-aided diagnosis in the interpretation of lesions on breast sonography

Abstract Rationale and objectives To investigate the potential usefulness of computer-aided diagnosis as a tool for radiologists in the characterization and classification of mass lesions on ultrasound. Materials and methods Previously, a computerized method for the automatic classification of breast lesions on ultrasound was developed. The computerized method includes automatic segmentation of the lesion from the ultrasound image background and automatic extraction of four features related to lesion shape, margin, texture, and posterior acoustic behavior. In this study, the effectiveness of the computer output as an aid to radiologists in their ability to distinguish between malignant and benign lesions, and in their patient management decisions in terms of biopsy recommendation are evaluated. Six expert mammographers and six radiologists in private practice at an institution accredited by the American Ultrasound Institute of Medicine participated in the study. Each observer first interpreted 25 training cases with feedback of biopsy results, and then interpreted 110 additional ultrasound cases without feedback. Simulating an actual clinical setting, the 110 cases were unknown to both the observers and the computer. During interpretation, observers gave their confidence that the lesion was malignant and also their patient management recommendation (biopsy or follow-up). The computer output was then displayed, and observers again gave their confidence that the lesion was malignant and their patient management recommendation. Statistical analyses included receiver operator characteristic analysis and Student t -test. Results For the expert mammographers and for the community radiologists, the A z (area under the receiver operator characteristic curve) increased from 0.83 to 0.87 ( P = .02) and from 0.80 to 0.84 ( P = .04), respectively, when the computer aid was used in the interpretation of the ultrasound images. Also, the A z values for the community radiologists with aid and for the expert mammographers without aid are similar to the A z value for the computer alone (A z = 0.83). Conclusion Computer analysis of ultrasound images of breast lesions has been shown to improve the diagnostic accuracy of radiologists in the task of distinguishing between malignant and benign breast lesions and in recommending cases for biopsy.
Incomplete rejoining of DNA double-strand breaks in unstimulated normal human lymphocytes

Abstract We investigated the repair kinetics of DNA single-strand breaks (SSBs) and double-strand breaks (DSBs) in unstimulated normal human peripheral blood lymphocytes (HPBL). SSBs and DSBs induced by γ-irradiation (at 0°C) were assayed without radiolabel by alkaline and neutral filter elution, respectively. Incubation of irradiated cells at 37°C for various lengths of time demonstrated that the percent DNA rejoined increased until it reached a plateau at approximately 60 min; this repair plateau underwent no substantial change when incubation continued for 20–24 h. The level of the plateau indicated how closely the elution profile of DNA from cells irradiated and incubated (experimental) resembled the elution profile of DNA from unirradiated cells (control). After 6 Gy and 60 min incubation, the alkaline elution profile of DNA from experimental cells from 5 donors was indistinguishable from that seen in DNA from control cells, suggesting that rejoining of SSBs was complete. In contrast after 100 Gy and 60 min incubation the neutral elution profile of DNA from cells from the same donors demonstrated that, compared to DNA from control cells, rejoining of DSBs was approximately two-thirds complete. In the range of 2–8 Gy, 85–104% of SSBs were rejoined after 60min incubation; in the range of 30–120 Gy, 46–80% of DSBs were rejoined after 60 min incubation. These unexpected results stand in contrast to our previous studies with confluent normal human diploid fibroblasts (HDF), in which rejoining of both SSBs and DSBs was greater than 90% complete by 60 min repair incubation and 100% complete after 18–24 h.
Generalized Nernst-Planck and Stefan-Maxwell equations for membrane transport

A generalized treatment of fluid transport in a porous membrane is developed on the basis of the ’’dusty‐gas’’ model, which is extended to include electrical forces due to charges on the solutes and the membrane. The Stefan–Maxwell diffusion equations are augmented to include viscous flow, and then phenomenologically generalized for the case of any fluid mixture. The resulting generalized transport equations are cast back into the original Stefan–Maxwell form. From these a set of generalized Nernst–Planck equations is obtained that includes convective flow and solute–solute interactions. It is demonstrated that viscous flow effects can be properly incorporated into the Stefan–Maxwell equations by augmenting the diffusion coefficients with viscosity terms. It is also shown that the main source of error in the usual simplified form of the Nernst–Planck equations lies in the treatment of convective flow terms. The generalized Nernst–Planck equations approach the proper limit for gases in both the Knudsen and...
The plane-strain essential work of fracture as a measure of the fracture toughness of ductile polymers

We have extended the essential work of fracture technique to allow for the determination of the plane-strain essential work of fracture. The new technique is to measure the specific work of fracture as a function of ligament length in deeply double edge notched samples. This type of data is then experimentally corrected to remove the plastic work of fracture and leave only the essential work of fracture as a function of ligament length. By extrapolating the essential work of fracture to zero-ligament length, we claim to be measuring the plane-strain essential work of fracture. This new technique was applied to two rubber toughened nylons and to a series of polyethylenes. The plane-strain essential work of fracture was found to be independent of thickness. Where comparison can be made to J-integral testing, the plane-strain essential work of fracture was similar to the critical J-integral, JIc.
Specification-based anomaly detection: a new approach for detecting network intrusions

Unlike signature or misuse based intrusion detection techniques, anomaly detection is capable of detecting novel attacks. However, the use of anomaly detection in practice is hampered by a high rate of false alarms. Specification-based techniques have been shown to produce a low rate of false alarms, but are not as effective as anomaly detection in detecting novel attacks, especially when it comes to network probing and denial-of-service attacks. This paper presents a new approach that combines specification-based and anomaly-based intrusion detection, mitigating the weaknesses of the two approaches while magnifying their strengths. Our approach begins with state-machine specifications of network protocols, and augments these state machines with information about statistics that need to be maintained to detect anomalies. We present a specification language in which all of this information can be captured in a succinct manner. We demonstrate the effectiveness of the approach on the 1999 Lincoln Labs intrusion detection evaluation data, where we are able to detect all of the probing and denial-of-service attacks with a low rate of false alarms (less than 10 per day). Whereas feature selection was a crucial step that required a great deal of expertise and insight in the case of previous anomaly detection approaches, we show that the use of protocol specifications in our approach simplifies this problem. Moreover, the machine learning component of our approach is robust enough to operate without human supervision, and fast enough that no sampling techniques need to be employed. As further evidence of effectiveness, we present results of applying our approach to detect stealthy email viruses in an intranet environment.
Single parents and wider families in the new context of legitimacy

The term ‘‘single parents’’ implies discrete entities in isolation, who by the adjective ‘‘single’’ are implied to be different from-and indeed deviant in regard to-parents in general. This paper l...
Blackfly (Diptera: Simuliidae) abundance in a lake outlet: test of a predictive model

A mathematical model based on assumptions of proportionality of filter-feeding insect larvae and their food supply and of the ability of the larvae to substantially reduce the sestonic food supply was developed. The predictions of the model were tested by censusing simuliid blackfly larvae in the outlet stream of a mesotrophic lake. Observed trends in simuliid density agree closely with the predictions. Two seston components (diatoms, detritus) increase downstream contrary to prediction. Potential predators of simuliids were censumed. Isoperla spp. decreased with increasing distance below the lake while the perlid stoneflies Calineuria and Hesperoperla seemed to be excluded from the outfall region.
Naroll's Analysis of Alcohol Problems

Raoul Naroll, in his book The Moral Order, emphasized the need for strong social affiliations. Weak social affiliations, which he called weak moralnets, result in alcohol problems and various other types of moral disorders. The author proposes to extend Naroll's explanation by describing a weak moralnet as a component of an intense conflict between an exaggerated desire for self-sufficiency and a frustrated desire for dependency. The intense conflict induces an addictive craving for alcohol because intoxication satisfies both conflicting desires. Strong moralnets prevent and alleviate alcohol problems by counteracting an exaggerated desire for self-sufficiency. A weaker desire for self-sufficiency enables the person to satisfy the desire for dependency.
Capacity efficiencies of time slot allocation schemes for adaptive antenna systems

The performance of the fixed-user-per-slot allocation method and the dynamic slot allocation method for time slot allocation in SDMA (Space-Division Multiple Access) is evaluated. The unsorted/sorted first come first serve (USFCFS/SFCFS), first fit (FF) and modified first fit (MFF) methods are studied. Each slot allocation scheme is evaluated with a number of beamforming algorithms. Two different capacity efficiencies are defined as the thresholds in the slot assignment, with one threshold potentially achieving higher efficiency but sacrificing some of the benefits an adaptive antenna system can provide. The computational complexity of the algorithms is considered when evaluating their performance. We define a new performance indicator, the effective relative angle (ERA), and show that it can be used in evaluating not only the performance of the power gain achieved by the antenna array, but also the capacity efficiency. The system performance benefit of the sorting process for the fixed-user-per-slot allocation method is also studied. Theoretical and simulation results are examined to try to find a rule of thumb for the capacity improvement over a conventional (single antenna) system of an adaptive antenna system using each slot allocation method.
Calcaneal chondroblastoma with pathologic fracture and recurrence.

Chondroblastomas account for 80% of cases. Local recurrence rates of ≤38% have been reported, most often because of inadequate resection, and have been associated with malignant conversion and metastasis. Adjuvant therapies can help minimize the incidence of local recurrence. Long-term follow-up examinations are recommended, given the protracted interval that can exist between recurrence and the potential for malignant conversion and metastasis. We present the case of a young, healthy, active male with a calcaneal chondroblastoma and associated pathologic fracture whose initial treatment consisted of curettage, hydrogen peroxide lavage, and allogeneic bone grafting. Recurrence developed at 15 months postoperatively and was treated with repeat curettage, high-speed burring, and reconstruction with steel Steinman pins and polymethylmethacrylate, resulting in no pain or recurrence at the 5-month follow-up point.
Novel Applications of Ultrasound Technology to Visualize and Characterize Myofascial Trigger Points and Surrounding Soft Tissue

Abstract Sikdar S, Shah JP, Gebreab T, Yen R-H, Gilliams E, Danoff J, Gerber LH. Novel applications of ultrasound technology to visualize and characterize myofascial trigger points and surrounding soft tissue. Objective To apply ultrasound (US) imaging techniques to better describe the characteristics of myofascial trigger points (MTrPs) and the immediately adjacent soft tissue. Design Four sites in each patient were labeled based on physical examination as active myofascial trigger points (A-MTrPs; spontaneously painful), latent myofascial trigger points (L-MTrPs; nonpainful), or normal myofascial tissue. US examination was performed on each subject by a team blinded to the physical findings. A 12∼5MHz US transducer was used. Vibration sonoelastography (VSE) was performed by color Doppler variance imaging while simultaneously inducing vibrations (∼92Hz) with a handheld massage vibrator. Each site was assigned a tissue imaging score as follows: 0, uniform echogenicity and stiffness; 1, focal hypoechoic region with stiff nodule; 2, multiple hypoechoic regions with stiff nodules. Blood flow in the neighborhood of MTrPs was assessed using Doppler imaging. Each site was assigned a blood flow waveform score as follows: 0, normal arterial flow in muscle; 1, elevated diastolic flow; 2, high-resistance flow waveform with retrograde diastolic flow. Setting Biomedical research center. Participants Subjects (N=9) meeting Travell and Simons' criteria for MTrPs in a taut band in the upper trapezius. Interventions Not applicable. Main Outcome Measures MTrPs were evaluated by (1) physical examination, (2) pressure algometry, and (3) three types of US imaging including gray-scale (2-dimensional [2D] US), VSE, and Doppler. Results MTrPs appeared as focal, hypoechoic regions on 2D US, indicating local changes in tissue echogenicity, and as focal regions of reduced vibration amplitude on VSE, indicating a localized, stiff nodule. MTrPs were elliptical, with a size of .16±.11cm 2 . There were no significant differences in size between A-MTrPs and L-MTrPs. Sites containing MTrPs were more likely to have a higher tissue imaging score compared with normal myofascial tissue ( P P Conclusions Preliminary findings show that, under the conditions of this investigation, US imaging techniques can be used to distinguish myofascial tissue containing MTrPs from normal myofascial tissue (lacking trigger points). US enables visualization and some characterization of MTrPs and adjacent soft tissue.
Mobile Labor, Multiple Tax Instruments, and Tax Competition

Abstract The tax competition literature shows that local governments keep property tax rates inefficiently low to prevent capital outflows, thereby underproviding local public goods. This paper adds mobile labor and an alternative tax instrument to the model. Jurisdictions have access to a property tax levied on land and capital, plus either a head tax or a labor tax. Scale economies in public good provision create incentives to use the property tax, but these incentives are not accompanied by increased incentives to underprovide public goods. In contrast, underprovision is associated with the use of a distortionary labor tax.
Citizenship and immigration a current review

The presence of immigrants and their activities challenge traditional notions of citizenship centred on the conflation of national and state membership. Four dimensions of citizenship— defined here as membership in a socio-political community—are identified: legal status, rights, identity, and participation. Discussion centres on the constraints and determinants of naturalization, the extent to which rights are linked to personhood rather than membership in a nation-state, and the challenge to state identity and cohesion produced by multiculturalism. It is suggested that future research should consider citizenship as participation. This dimension highlights how immigrants’ transnational activities challenge traditional views of citizenship. We cannot, however, dismiss the importance of the state. The concept of participation is therefore also important since it focuses attention on dynamic interactions between the individual and the nation-state.
Natural Infection of a Great Egret (Casmerodius albus) with Eastern Equine Encephalitis Virus

In July 2001, a great egret (Casmerodius albus) was found dead in Charlton County, Georgia (USA) and submitted to the Southeastern Cooperative Wildlife Disease Study (The University of Georgia, Athens, Georgia). Histopathologic findings included severe hepatic necrosis and necrosis of sheathed arterioles. Eastern equine encephalitis (EEE) virus was isolated from brain and heart using Vero cells and was identified using a standard micro-neutralization test and reverse transcription polymerase chain reaction (rtPCR). Streptavidin-biotin alkaline phosphatase immunohistochemistry using mouse anti-EEE virus monoclonal antibody demonstrated EEE antigen within cells of the sheathed arterioles and scattered mononuclear cells in the splenic parenchyma. To the authors' knowledge, this is the first description of natural infection and pathologic effects of EEE virus infection in a great egret.
Rapid analysis of the chemical composition of agricultural fibers using near infrared spectroscopy and pyrolysis molecular beam mass spectrometry

The chemical composition of a variety of agricultural biomass samples was analyzed with near infrared spectroscopy and pyrolysis molecular beam mass spectroscopy. These samples were selected from a wide array of agricultural residue samples and included residues that had been subjected to a variety of different treatments including solvent extractions and chemical modifications. This analysis showed that both spectroscopic tools, coupled with multivariate analytical techniques, could be used to differentiate the samples and accurately predict the chemical composition of this disparate set of agricultural biomass samples.
Fluorescence probes in metastatic B16 melanoma membranes

Abstract Fluorescence probe molecules, trans-parinaric acid and 1,6-diphenylhexatriene, were utilized to characterize the structure of plasma membranes, microsomes and mitochondria from B16 melanoma cells. High metastatic B16-F10 and low metastatic B16-F1 melanoma cell lines had markedly different membrane structures. The fluorescence polarization, fluorescence lifetime and limiting anisotropy of trans-parinaric acid were significantly lower ( P ) in all three membrane fractions of the B16-F1 cell line than in the corresponding membranes of the B16-F10 cell line. These data indicated less restriction to rotational motion in the solid lipid domains of B16-F1 cell membranes preferentially sensed by trans-parinaric acid. The limiting anisotropy of both trans-parinaric acid and 1,6-diphenyl-1,3,5-hexatriene was significantly lower in the outer monolayer than the inner monolayer of the plasma membrane of B16-F1 cells but not in B16-F10 cells. A breakpoint in Arrhenius plots of fluorescence near 30–34°C indicated the presence of a phase separation that was assigned to the inner monolayer of the plasma membrane. However, no differences in this breakpoint temperature were noted between the B16-F1 and B16-F10 melanoma membranes. Thus, more fluid solid membrane domains and a distinct transbilayer fluidity difference were characteristic of plasma membranes from low metastatic B16-F1 melanoma cells in contrast to high metastatic B16-F10 melanoma cells.
Estimating Nonmotorized Travel Demand

The modeling of nonmotorized travel demand has mostly been conducted at the large spatial level (e.g., city, county, or census tract level) by using data from the Bureau of the Census and the National Household Travel Survey. This paper introduces a modeling approach for estimating the mode share of nonmotorized trips by using data from multiple sources at a finer spatial scale. The correlations between a number of socioeconomic, environmental, and infrastructural factors and the nonmotorized share of the daily commute are analyzed at the level of the census block group. A neighborhood analysis concept is developed to take the length of nonmotorized trips into consideration. Multiple regression analysis shows that employment density, the percentage of the student population, median household income, and average sidewalk length together provide the strongest power for prediction of the nonmotorized mode share. The potential applications of the methodology and the implications for data collection are also d...
Disguised Protectionism, Global Trade Rules and Alien Invasive Species

Current international law strongly favors policies designed to make imports safer (e.g., in terms of invasive species) over policies explicitly designed to discourage imports. We show that this preference may be counterproductive. A externality in trade is incorporated into a political-economy model of policy formation. Nations can address the externality by inspecting cargo and imposing a fine on contaminated imports. We compare the equilibrium when inspection is the only policy option relative to the equilibrium that emerging when nations may also manipulate the tariff. Ruling out the tariff causes socially excessive stringency in general, social welfare losses if domestic supply is highly inelastic, and in some circumstances an increase in the real tariff, measured as the difference between world and domestic prices.
A parameterization of electro-weak mass matrices for quarks

We discuss quark flavor mixing and CP violation using a 10 parameter quark mass matrix in the electro-weak basis. The matrix handles the high mass of the top quark, 174±16 GeV, and contains two CP violating phases. We show that this scheme favors minimal CP violation by a single phase factor and leads to maximal CP violation in the standard parameterization of the quark flavor mixing matrix.
Adaptive block sampling for spectrum sensing

This paper considers spectrum access in wideband channels and its objective is to design an agile and reliable mechanism for identifying spectrum opportunities. Driven by the need for reducing the time required for identifying spectrum opportunities, the idea of data-adaptive and sequential block sampling is proposed, through which instead of examining each channel individually, a cognitive user takes samples that are linear combinations of simultaneous measurements from multiple channels. If such coarse samples indicate that the block of channels contains at least a vacant (unused) channel, then the channels are examined individually in order to accumulate more information about their spectral occupancy states, and otherwise, the entire block is discarded and the process resumes sequentially by examining the next block of channels.
Social service by university students in Mexico: Thoughts for the United States

Abstract In this study, two U.S. researchers report findings and conclusions from a study of Servicio Social, a Mexican program of social service by university students. Servicio Social has made important contributions to the welfare of the Mexican people, particularly in health care. The researchers look at the program to try to understand its purposes in Mexico, to assess some of the program's strengths and weaknesses, and to suggest possible considerations for national service policy in the United States.
Super-Weyl transformations in heterotic superstring geometry

Abstract The super-Weyl transformations of ( p , 0) supergravity are defined and calculated. It is shown, in the Wess-Zumino gauge, that the Einstein and heterotic string actions are invariant under super-Weyl transformations, and that ( p , 0) superspace is superconformally flat.
Anti-Bombesin Monoclonal Antibodies Modulate Fetal Mouse Lung Growth and Maturation In Utero and in Organ Cultures

Fetal pulmonary neuroendocrine cells (PNECs) contain abundant gastrin-releasing peptide (GRP, mammalian bombesin-like pep- tide (BLP)). Previously, addition of bombesin resulted in increased fetal lung growth and maturation in utero and in organ cultures. A monoclonal antibody (mAb) to bombesin @All) blocked baseline automaturation of lung organ cultures in serum-free medium. In the present study, we analyze lung development following daily in utero administration of 2All from ges- tational days 15-18. Fetal lung treated with 2All and then harvested on day 18 demonstrated a dose-dependent decrease in surfactant phospholipid synthesis compared to controls treated with MOPC, an unreactive mAb. However, 2All-treated fetal lung harvested on day 17 showed paradoxical increases in 3H-choline incorporation into saturated phosphatidylcholine, 3H-thymidine incorporation into DNA, and relative numbers of differenti- ated type I1 pneumocytes. In serum-containing day 17 lung organ cultures, 2A11 stimulated choline and thymidine incorporation. Since epidermal growth factor (EGF) is the only agent besides bombesin known to stimulate both fetal lung growth and maturation, we added EGF to serum-free cul- tures and reconstituted the stimulatory effects. A murine EGF receptor mAb (ERA) blocked 2All-induced lung growth and maturation in serum- containing cultures, and this effect was overcome by adding EGF. In vivo, ERA also blocked stimulatory effects of 2All in fetal lung on day 17. These observations suggest that EGF receptor up-regulation may maintain lung growth and maturation if BLP levels are diminished on day 17. Nonethe- less, BLPs appear to be involved in lung maturation on day 18, supporting a role for PNECs in normal lung development. o 1993 Wiley-Liss, Inc.
Uniformly Most Accurate Upper Tolerance Limits for Monotone Likelihood Ratio Families of Discrete Distributions

Abstract The theory of uniformly most accurate upper tolerance limits is presented for families of discrete distributions having monotone likelihood ratios. Explicit formulae are derived for binomial, negative-binomial and Poisson distributions. The relationship to systems of uniformly most accurate upper confidence limits is exposed.
Arrays of horizontally-oriented mini-reservoirs generate steady microfluidic flows for continuous perfusion cell culture and gradient generation

This paper describes the use of arrays of horizontally-oriented reservoirs to deliver liquids through microchannels at a constant flow rate over extended periods of time (hours to days). The horizontal orientation maintains a constant hydraulic pressure drop across microfluidic channels even as the volumes of liquids within the reservoirs change over time. For a given channel–reservoir system, the magnitude of the flow velocity depends linearly on the height difference between reservoirs. The simple structure and operation mechanism make this pumping system versatile. A one-inlet–one-outlet system was used to continuously deliver media for perfusion cell culture, and an array of inlet reservoirs coupled to an outlet reservoir via microchannels was used to drive flows of multiple laminar streams. The parallel pumping scheme conveniently generated various smooth and step concentration gradients, and allowed evaluation of the effect of colchicine on myoblasts. Since the reservoir arrays are configured to be compatible with commercialized multichannel pipettors designed for 96 well plate handling, this simple pumping scheme is envisioned to be broadly useful for medium to high throughput microfluidic perfusion cell culture assays, cell migration assays, multiple laminar flow drug tests, and any other applications needing multiple microfluidic streams.
Antitumor Activity of Ribonuclease Multimers Created by Site-Specific Covalent Tethering

Site-specific cross-linking can generate homogeneous multimeric proteins of defined valency. Pancreatic-type ribonucleases are an especially attractive target, as their natural dimers can enter mammalian cells, evade the cytosolic ribonuclease inhibitor (RI), and exert their toxic ribonucleolytic activity. Here, we report on the use of eight distinct thiol-reactive cross-linking reagents to produce dimeric and trimeric conjugates of four pancreatic-type ribonucleases. Both the site of conjugation and, to a lesser extent, the propinquity of the monomers within the conjugate modulate affinity for RI, and hence cytotoxicity. Still, the cytotoxicity of the multimers is confounded in vitro by their increased hydrodynamic radius, which attenuates cytosolic entry. A monomeric RI-evasive variant of bovine pancreatic ribonuclease (RNase A) inhibits the growth of human prostate and lung tumors in mice. An RI-evasive trimeric conjugate inhibits tumor growth at a lower dose and with less frequent administration than ...
Determination of nanomolar concentrations of nitrite and nitrate in natural waters using long path length absorbance spectroscopy

The concentrations of nitrite and nitrate in many natural waters are below the detection limits of conventional colorimetric analysis. A liquid core waveguide (LCW) has been used to extend the sensitivity of conventional colorimetric nitrite and nitrate determinations by more than an order of magnitude. Long path length absorbance spectroscopy (LPAS) with a 4.5 m path length LCW made of Teflon AF-2400 provides detection limits for NO2- and NO3- equal to 0.5 and 1.5 nM, respectively. The absorbance response of the LPAS system varies linearly with concentration. Calculations of azo dye molar absorbance using LPAS observations at nanomolar concentrations are in excellent agreement with molar absorbance results obtained with conventional measurement systems at much higher concentrations. For 1 nM NO2- and NO3- concentration differences, the 4.5 m path length LCW used in this work produces absorbance differences on the order of 0.02. No significant changes in the behavior of the LPAS system have been observed ...
Advanced sensing towards improved forklift safety

The National Institute of Standards and Technology's Intelligent Systems Division has been researching advanced three-dimensional (3D) imaging sensors and their use in manufacturing towards improving forklift safety. Experiments are presented in this paper and that show how the sensors can augment a forklift operator's perception of obstacles nearby. Interoperability of the obstacle/pedestrian detection information from these sensors to the facility or other forklifts for broader alerts is also possible.
Clock gene expression in the murine gastrointestinal tract: endogenous rhythmicity and effects of a feeding regimen.

Background & Aims: Based on observations that the gastrointestinal tract is subject to various 24-hour rhythmic processes, it is conceivable that some of these rhythms are under circadian clock gene control. We hypothesized that clock genes are present in the gastrointestinal tract and that they are part of a functional molecular clock that coordinates rhythmic physiologic functions. Methods: The effects of timed feeding and vagotomy on temporal clock gene expression (clock, bmal1, per1–3, cry1-2) in the gastrointestinal tract and suprachiasmatic nucleus (bmal, per2) of C57BL/6J mice were examined using real-time polymerase chain reaction and Western blotting (BMAL, PER2). Colonic clock gene localization was examined using immunohistochemistry (BMAL, PER1-2). Results: Clock immunoreactivity was observed in the myenteric plexus and epithelial crypt cells. Clock genes were expressed rhythmically throughout the gastrointestinal tract. Timed feeding shifted clock gene expression at the RNA and protein level but did not shift clock gene expression in the central clock. Vagotomy did not alter gastric clock gene expression compared with sham-treated controls. Conclusions: The murine gastrointestinal tract contains functional clock genes, which are molecular core components of the circadian clock. Daytime feeding in nocturnal rodents is a strong synchronizer of gastrointestinal clock genes. This synchronization occurs independently of the central clock. Gastric clock gene expression is not mediated through the vagal nerve. The presence of clock genes in the myenteric plexus and epithelial cells suggests a role for clock genes in circadian coordination of gastrointestinal functions such as motility, cell proliferation, and migration.
The effects of 5-hydroxytryptophan and 5-hydroxytryptamine on dopamine synthesis and release in rat brain striatal synaptosomes

— The effects of 5-hydroxytryptophan (5-HTP) and serotonin (5-HT) on dopamine synthesis and release in rat brain striatal synaptosomes have been examined and compared to the effects of tyramine and dopamine. Serotonin inhibited dopamine synthesis from tyrosine, with 25% inhibition occurring at 3 μM-5-HT and 60% inhibition at 200 μM. Dopamine synthesis from DOPA was also inhibited by 5-HT, with 30% inhibition occurring at 200 μ. At 200 μM-5-HTP, dopamine synthesis from both tyrosine and DOPA was inhibited about 70%. When just the tyrosine hydroxylation step was measured in the intact synaptosome, 5-HT, 5-HTP, tyramine and dopamine all caused significant inhibition, but only dopamine inhibited soluble tyrosine hydroxylase [L-tyrosine 3-monooxygenase; L-tyrosine, tetrahydropteridine oxygen oxidoreductase (3-hydroxylating); EC 1.14.16.2] prepared from lysed synaptosomes. Particulate tyrosine hydroxylase was not inhibited by 10 μM-5-HT, but was about 20% inhibited by 200 μM-5-HT and 5-HTP. At 200 μM both 5-HT and 5-HTP stimulated endogenous dopamine release. These experiments suggest that exposure of dopaminergic neurons to 5-HT or 5-HTP leads to an inhibition of dopamine synthesis, mediated in part by an intraneuronal displacement of dopamine from vesicle storage sites, leading to an increase in dopamine-induced feedback inhibition of tyrosine hydroxylase, and in part by a direct inhibition of DOPA decarboxylation.
Sex-role traditionalism and assertiveness in puerto rican women living in the united states

Historical and clinical descriptions of Puerto Rican women living in the United States suggest that they are more sex-role traditional and less assertive than other American women, even though working and studying in the United States results in acculturation. These claims have not been examined with reliable measures. The purpose of this study was to determine whether generation (first versus second) and education affect sex-role traditionalism and assertiveness in Puerto Rican women living in the United States. In all, 278 Puerto Rican women (18 to 55 years of age) completed a questionaire containing demographic questions and measures of sex-role traditionalism and assertiveness. Sex-role traditionalism was measured by a scale designed especially for this study, with items derived from the Attitudes Toward Women Scale (Spence, Helmreich, & Stapp, 1973) and the Attitudes Toward Feminism Scale (Smith, Ferree, & Miller, 1975), plus nine items designed specifically for Puerto Rican women. Assertiveness was measured by the Adult Self-Expression Scale (Gay, Hollandsworth, & Galassi, 1975). Bivariate hypotheses were tested to determine whether being second generation and better educated decreases sex-role traditionalism and increases assertiveness. All of the major hypotheses were supported. Two limitations of the study as well as clinical implications of the findings are discussed.
Monogerm sugar-beet seed production experiments

Eight experiments investigated how different sowing and harvest dates, plant populations and fertilizers affect yield, germination and size of seed from hybrid monogerm sugar-beet seed crops, grown in situ when raised under barley cover in Lincolnshire, or open sown in Oxfordshire. Weather at seed harvest was wetter than average in 1968, average in 1969, and drier in 1970. Most seed of good quality came from plant populations of 300000 plants/ha sown in early July, given ample P and K fertilizer in the seed bed and 150–200 kg/ha of N in the spring of the second year in Oxfordshire or 200–250 kg/ha N in Lincolnshire. Harvesting in early September on average yielded most seed. Methods used to grow multigerm seed proved suitable also for monogerm seed but the percentage germination was lower for monogerm than multigerm seed.
Contrasting patterns of wetland use by sympatric larids in winter

The population dynamics and behaviour of the larid assemblage of a Mediterranean coastal wetland, the Vourkari inlet in Greece, were studied during the winter of 2008–2009. More black-headed gulls (Larus ridibundus) were seen in the inlet in December, more Mediterranean gulls (Larus melanocephalus) were present from mid-January to mid-February, while little variation was observed in yellow-legged gull (Larus michahellis) numbers throughout winter. Bird numbers remained stable through the day for the yellow-legged gull, but fewer black-headed and Mediterranean gulls were present in the late morning than the other periods. Diurnal activity patterns showed that feeding was the primary behaviour for yellow-legged gulls and resting and sleeping for black-headed and Mediterranean gulls, with locomotion being equally important for all species. All larids were primarily feeding in the late morning period, but yellow-legged gulls were doing so in much higher proportions. These contrasting patterns suggested that the Vourkari inlet was more important as a day roost for black-headed and Mediterranean gulls and a preferred feeding ground for yellow-legged gulls. Furthermore, results suggested that resting and sleeping were interchangeable activities and all other activities had more or less the same time demands on a daily basis, and also a consistent pattern across species in sleeping proportions that might indicate cross-species synchrony in sleep patterns; however future research is needed to resolve these issues. This study provided important new information on the winter ecology of three larids and revealed patterns of wetland use by these species that could help assess the importance of certain areas and improve coastal habitat management strategies to benefit birds.
PROOF FRAMES OF PRESERVICE ELEMENTARY TEACHERS

This study asked 101 preservice elementary teachers enrolled in a sophomore-level mathematics course to judge the mathematical correctness of inductive and deductive verifications of either a familiar or an unfamiliar statement. For each statement, more than half the students accepted an inductive argument as a valid mathematical proof. More than 60% accepted a correct deductive argument as a valid mathematical proof; 38% and 52% accepted an incorrect deductive argument as being mathematically correct for the familiar and unfamiliar statements, respectively. Over a third of the students simultaneously accepted an inductive and a correct deductive argument as being mathematically valid. The concept of proof is of great importance in the study of mathematics. Smith and Henderson (1959) stated, for example, that "the idea of proof is one of the pivotal ideas in mathematics. It enables us to test the implication of ideas, thus establishing the relationship of the ideas and leading to the discovery of new knowledge" (p. 178). Research has explored this important topic with elementary and high school students (Bell, 1976, 1979; Galbraith, 1981; Lester, 1975; Williams, 1980). Two studies are most pertinent to our research. Fischbein and Kedem (1982) investigated whether high school students understand that mathematical proof requires no further empirical verification. They verified empirically their assumption that "students, after finding or learning a correct proof for a certain mathematical statement, will continue to consider that surprises are still possible, that further checks are desirable in order to render the respective statement more trustworthy" (p. 128). Vinner (1983) focused on the question, What makes a given sequence of correct mathematical arguments a mathematical proof in the eyes of high school students? He asked students to give their preference for proving a particular case of a previously proved statement. He found they preferred using a particularization of the deductive proof rather than the general result. The general proof was viewed as a method to examine and to verify a particular case. Vinner further observed that students judged a mathematical proof on its appearance, relying on ritualistic aspects of proof. In this study, we investigated the views of proof of a different population, preservice elementary school teachers. Further, we investigated a different aspect of proof, one related to inductive and deductive reasoning. The views of proof held by preservice elementary school teachers are important. Because proof receives very limited attention in the elementary school curriculum, the main source of children's experience with verification and proof is the classroom teacher. Classroom teachers' understanding of what constitutes mathematical proof is important, even though they do not directly teach that topic. If teachers lead their students to believe that a few well-chosen examples constitute proof,
Instrinsic linewidth of a homogeneously broadened laser with arbitrary output-mirror coupling

Abstract By treating the boundary conditions correctly, we compute the linewidth of a laser with arbitrary output coupling below and above threshold. In the limit of unit output-mirror transmission, for which any semblance of the cavity to a lasing cavity is completely untenable, we show that the laser linewidth reduces to the natural linewidth of spontaneous emission by atoms in free space. Dependences of the linewidth on the cavity transmission are predicted to be at variance with previously obtained results. We also find a power-independent contribution to the intrinsic linewidth well above threshold.
A.c. impedance of niobium triselenide cathode in secondary lithium cells

Niobium triselenide is one of the cathode materials being evaluated at JPL for ambient temperature secondary lithium batteries for space applications. The mechanism of reduction of NbSe3 involves two steps, 1 mole of Li intercalating in the first step and 2 moles of Li intercalating at lower potentials in the second step. The a.c. impedance behaviour of the NbSe3 cathode under various conditions, i.e. at different reduction potentials, after discharges at various d.c. potentials and after charge/discharge cycling is discussed.
Biosynthesis of trans-farnesyl triphosphate in Gibberella fujikuroi.

Abstract A 3H-containing polyphosphate ester of trans-farnesol was isolated from incubations of cell-free extracts of mycelia of the fungus Gibberella fujikuroi (LiLy-1) with [1-3H]farnesyl pyrophosphate, ATP and MgCl2. The compound was identified as trans-[1-3H]farnesyl triphosphate by co-chromatography with authentic farnesyl triphosphate and by the release of its organic moiety by alkaline phosphatase and the co-chromatography of this product with authentic trans-farnesol. trans-[1-3H]Farnesyl monophosphate and trans-[1-3H]farnesol were also identified as products of phosphatase hydrolysis. The formation of this product involved the transfer of the terminal phosphate from [γ-32P]ATP to trans-[1-3H]farnesyl pyrophosphate catalyzed by a partially purified, phosphatase-free enzyme. This transfer was demonstrated by measuring the 3H:32P ratio in the product. Of the nucleotides tested, ATP was found to be the best substrate for this reaction, but other nucleotide triphosphates did yield low activities. The enzyme displayed absolute specificity for trans-farnesyl pyrophosphate. Other phosphate esters of trans-farnesol, free trans-farnesol and pyrophosphate esters of trans-geraniol and trans-geranylgeraniol did not serve as substrates for this reaction.
The CT appearance of pleural and extrapleural disease in lymphoma.

Abstract OBJECTIVE: Pleural effusions in patients with lymphoma that are assumed to be related to malignancy are attributed to either lymphatic obstruction by tumour with resultant decreased clearance of pleural fluid, or direct tumour involvement of the pleura. The purpose of our study was to determine how often pleural or extrapleural disease was detected by computed tomography (CT) of patients with pleural effusions and primary or recurrent lymphoma. METHODS AND MATERIALS: We reviewed CT examinations showing evidence of pleural effusion in 61 patients with a diagnosis of primary or recurrent lymphoma and no history of other systemic disorders, including infection. The study population consisted of patients with non-Hodgkin's lymphoma ( n = 44) or Hodgkin's disease ( n = 17); both primary disease ( n = 11) and recurrent disease ( n = 50) were represented. Each CT examination was evaluated for the presence of disease involving the visceral and parietal pleura and extrapleural space, mediastinal adenopathy, and pulmonary parenchymal disease. RESULTS: Fourteen patients (23%) (nine with non-Hodgkin's lymphoma and five with Hodgkin's disease) had parietal pleural disease (thickening or nodules). Eighteen patients (30%) (14 with non-Hodgkin's lymphoma, four with Hodgkin's disease) had tumour or enlarged lymph nodes in the extrapleural space. Forty-three patients (70%) had mediastinal lymphadenopathy. Patients who received intravenous contrast did not have evidence of visceral pleural abnormalities or underlying pulmonary parenchymal disease. CONCLUSION: Forty-one percent of the patients with lymphoma and pleural effusions had CT evidence of pleural and/or extrapleural disease. The majority of the patients with extrapleural disease had adjacent posterior mediastinal disease.
Appreciative inquiry as a mode of action research for community psychology

In this article, the authors highlight the potential for rethinking approaches to community and social change interventions that draw on participatory action research at the organizational and community level. They distinguish problem-centric from opportunity-centric approaches to social change. Theory on social norms suggests that problem-centric approaches work with the momentum of norms without substantively changing them. By contrast, opportunity-centric approaches have the potential to reframe and dramatically shift organizational and community norms. Appreciative inquiry (AI), a growing practice in organization development, is presented as an example of opportunity-centric change that induces innovation and collaboration through participatory methods. It is distinct from other methods that focus on resolving problems in organizations. The authors illustrate how an AI Summit, a large-scale inquiry designed with four phases: Discover, Dream, Design, and Destiny, can assist in an opportunity-centric process. They conclude by describing how opportunity-centric methodologies like AI fit well with the tenets and concerns of community psychologists. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 1019–1036, 2007.