cssi/SciSciGPT-SciSciNet huggingface dataset:
Physical and chemical studies on glycoproteins: II. Isolation and characterization of oligosaccharides from porcine submaxillary glycoproteins☆

Abstract Treatment of porcine submaxillary glycoproteins with alkaline borohydride (0.1N NaOH, 0.3N NaBH 4 for 120 hours at 28 °) liberated approximately one-third of the carbohydrate in the form of reduced oligosaccharides. The oligosaccharides were isolated by a procedure that included chromatography on Dowex-1 (formate), paper and char-coal-celite. The following compounds were identified by structural determination: α- l -fucopyranosyl-(1 → 2)-β- d -galactopyranosyl-(1 → 4)- d - N -acetylgalactosaminitol; α- l -fuco-pyranosyl-(1 → 2)-β- d -galactopyranosyl-(1 → 4)-[α- N -glycolyhieuraminyl-(2 → 6)]- d - N -acetylgalactosaminitol; α- N -glycolylneuraminyl-(2 → 6)- d - N -acetylgalactosaminitol; α- l -fucopyranosyl-(1 → 2)- d -galactitol; d -galactitol; and d - N -acetylgalactosaminitol. Two additional oligosaccharides were assigned the following structures on the basis of periodate oxidation and their inhibition of the human A-anti A hemagglutination reaction: α- d - N -acetylgalactosaminyl-(1 → 3)-[α- l -fucopyranosyl-(l → 2)]-β- d -galactopyranosyl-(1 → 4)- d - N -acetylgalactosaminitol and α- d - N -acetylgalactosaminyl-(l → 3)-[α- l -fucopyranosyl-(1 → 2)]-β- d -galactopyranosyl-(1 → 4)-[α- N -glycolylneuraminyl-(2 → 6)]- d - N -acetylgalactosaminitol. The carbohydrate structure of the porcine submaxillary glycoproteins is discussed in relation to the above oligosaccharides, ovine and bovine submaxillary glycoproteins, and the blood group substances.
Simulation neuer System-Architekturen mittels virtueller Maschinen

The 4300-Maschine Simulation facility is an enhancement package for the control program (CP) of VM/370. It allows the function of a virtual 4 300-Maschine in addition to the already available IBM/360 and IBM/370 virtual machines. 4300-Maschine simulation provides all functions to simulate all new 4300-Maschine instructions, the 4300-Maschine storage and I/O instructions.
Interpreting the 1974 Congressional Election

What factors best account for the 1974 congressional election results? Were the Democratic party gains in House seats due mainly to the behavior of strategic politicians" who sought or accepted candidacies and raised effective campaign war chests? Or were the Democratic gains due more to the impact of Watergate and the economy on voters' choices?
Sentinel lymph node biopsy is prognostic but not therapeutic for thick melanoma

Background Sentinel lymph node biopsy (SNB) as a staging and therapeutic procedure in melanomas 1–4 mm in thickness has been investigated extensively, however, the clinical value of SNB in thick melanomas is poorly understood. Methods Patients undergoing operation for clinically node-negative melanoma >4 mm in depth between 2003 and 2010 were identified in the Surveillance Epidemiology and End Results registry. Two groups were constructed: one with a wide excision with SNB and the other with wide excision alone. Results A total of 4,571 patients with clinically node-negative, thick melanoma were identified. The median age was 71 years, 96.9% were white, and 64.3% were male. SNB was performed in 2,746 (60.1%) and was positive in 32.2%. Univariate analysis demonstrated SNB was associated with younger age (64 vs 75 years; P < .001) and extremity primaries (P < .0001). On logistic regression, advanced age (P < .001), female sex (P = .009), and location in the head and neck region (P < .001) were associated with observation. On log-rank analysis, improved 5-year disease-specific survival (DSS) was associated with SNB (65 vs 62%; P = .008), location in the extremity versus head and neck or trunk (67 vs 61.5 and 60.3%; P = .004), female sex (69 vs 61%; P < .001), and no ulceration (74 vs 54%; P < .001). On Cox regression analysis, advanced age (P < .001), male sex (P = .01), trunk location (P = .0001), and ulceration (P < .001) continued to be associated with DSS. SNB was not associated with survival (P = .20). SNB status was a robust predictor of survival; a negative SNB had a 5-year DSS of 75.3 versus 44.1% (P < .0001), with a positive node. Conclusion For patients with clinically node-negative, thick melanoma, SNB is a staging but not therapeutic procedure.
Interior region-of-interest reconstruction using a small, nearly piecewise constant subregion

Purpose: To develop a method to reconstruct an interior region-of-interest (ROI) image with sufficient accuracy that uses differentiated backprojection (DBP) projection onto convex sets (POCS) [H. Kudo et al., ''Tiny a priori knowledge solves the interior problem in computed tomography'', Phys. Med. Biol. 53, 2207-2231 (2008)] and a tiny knowledge that there exists a nearly piecewise constant subregion. Methods: The proposed method first employs filtered backprojection to reconstruct an image on which a tiny region P with a small variation in the pixel values is identified inside the ROI. Total variation minimization [H. Yu and G. Wang, ''Compressed sensing based interior tomography'', Phys. Med. Biol. 54, 2791-2805 (2009); W. Han et al., ''A general total variation minimization theorem for compressed sensing based interior tomography'', Int. J. Biomed. Imaging 2009, Article 125871 (2009)] is then employed to obtain pixel values in the subregion P, which serve as a priori knowledge in the next step. Finally, DBP-POCS is performed to reconstruct f(x,y) inside the ROI. Clinical data and the reconstructed image obtained by an x-ray computed tomography system (SOMATOM Definition; Siemens Healthcare) were used to validate the proposed method. The detector covers an object with a diameter of {approx}500 mm. The projectionmore » data were truncated either moderately to limit the detector coverage to diameter 350 mm of the object or severely to cover diameter 199 mm. Images were reconstructed using the proposed method. Results: The proposed method provided ROI images with correct pixel values in all areas except near the edge of the ROI. The coefficient of variation, i.e., the root mean square error divided by the mean pixel values, was less than 2.0% or 4.5% with the moderate or severe truncation cases, respectively, except near the boundary of the ROI. Conclusions: The proposed method allows for reconstructing interior ROI images with sufficient accuracy with a tiny knowledge that there exists a nearly piecewise constant subregion.« less
Insights into the mechanistic and synthetic aspects of the Mo/P-catalyzed oxidation of N-heterocycles

A Mo/P catalytic system for an efficient gram-scale oxidation of a variety of nitrogen heterocycles to N-oxides with hydrogen peroxide as terminal oxidant has been investigated. Combined spectroscopic and crystallographic studies point to the tetranuclear Mo4P peroxo complex as one of the active catalytic species present in the solution. Based on this finding an optimized catalytic system has been developed. The utility and chemoselectivity of the catalytic system has been demonstrated by the synthesis of over 20 heterocyclic N-oxides.
A survey on acoustic signature recognition and classification techniques for persistent surveillance systems

Application of acoustic sensors in Persistent Surveillance Systems (PSS) has received considerable attention over the last two decades because they can be rapidly deployed and have low cost. Conventional utilization of acoustic sensors in PSS spans a wide range of applications including: vehicle classification, target tracking, activity understanding, speech recognition, shooter detection, etc. This paper presents a current survey of physics-based acoustic signature classification techniques for outdoor sounds recognition and understanding. Particularly, this paper focuses on taxonomy and ontology of acoustic signatures resulted from group activities. The taxonomy and supportive ontology considered include: humanvehicle, human-objects, and human-human interactions. This paper, in particular, exploits applicability of several spectral analysis techniques as a means to maximize likelihood of correct acoustic source detection, recognition, and discrimination. Spectral analysis techniques based on Fast Fourier Transform, Discrete Wavelet Transform, and Short Time Fourier Transform are considered for extraction of features from acoustic sources. In addition, comprehensive overviews of most current research activities related to scope of this work are presented with their applications. Furthermore, future potential direction of research in this area is discussed for improvement of acoustic signature recognition and classification technology suitable for PSS applications.
Retrovirus-mediated transfer of the human O6-Methylguanine-DNA methyltransferase gene into a murine hematopoietic stem cell line and resistance to the toxic effects of certain alkylating agents

Abstract O6-Methylguanine-DNA methyltransferase (MGMT) is an important DNA repair protein that plays a key role in cancer chemotherapy by alkylating agents such as carmustine (BCNU) and Dacarbazine (DTIC). Therapy by BCNU and DTIC is reduced by dose-limiting hematological toxicity as a result of low MGMT repair activity in bone marrow cells. In this study, we have constructed a Moloney murine leukemia virus retroviral vector containing the human mgmt gene. High-titer retrovirus producer cell lines have been generated. Retroviral-mediated transfer of the human mgmt gene into murine multi-potent hematopoietic stem cells, FDCP-1, resulted in the expression of a high level of MGMT activity. In comparison with the control cells that were transduced with the parent vector, the MGMT-expressing clones were considerably more resistant to the cytotoxicity of the methylating agents, such as N-methyl-N′-nitro-N-nitrosoguanidine, N-nitroso-N-methylurea, and temozolomide, as well as the chloroethylating agents 1-(2-chloroethyl)-1-nitrosourea and BCNU. The protection provided by MGMT could be eliminated by the MGMT inactivator O6-benzylguanine. Thus, the principal lethal lesions produced by these alkylating agents in the murine hematopoietic stem cells and the MGMT deficiency in these cells can be complemented by retroviral-mediated gene transduction.
Digital mobilization in disaster response: the work & self-organization of on-line pet advocates in response to hurricane sandy

This ethnographic study of a Facebook Page founded on 28 October 2012 in anticipation of Hurricane Sandy's US landfall reveals how on-line pet advocates--a large but loosely organized social movement--mobilized their ad hoc discretionary activities to more cooperative, organized work to assist numerous displaced pets. The investigation shows how innovations around 'crossposting' to create a more persistent form of visual data management were important. It describes how these innovations produced an improvised case management system around which members of the pet-advocacy crowd could collectively work to help displaced pets. The paper connects to the CSCW and organizational science literature to consider how this emergent community articulated work and structured the mission of the Page.
Superficial siderosis: a case report and review of the literature.

Background A 48-year-old man with a past history of a car-accident-induced coma at the age of 3 years and spontaneous bilateral subdural hematomas at the age of 34 years presented with a 2-year history of worsening gait difficulties, clumsiness and dysarthria. CT scans of the brain taken during the 6 months leading up to his presentation had revealed chronic subarachnoid hemorrhage, but angiograms had not been able to identify the source of bleeding. Investigations Neurological examination, brain MRI scan, lumbar puncture, four-vessel cerebral angiogram and spinal angiogram. Diagnosis Superficial siderosis; a complete review of the current literature on the condition is provided. Management Iron chelating agents.
Gas‐Phase Desorption of Diphenylamine from Porous Silicon

In this work, the desorption of diphenylamine from different five types of porous Si substrates under low vacuum is examined. These substrates include (i) freshly prepared porous Si; (ii) ambient‐oxidized porous Si, and rapidly oxidized porous Si samples processed at the maximum temperatures of (iii) 400°C, (iv) 600°C, and (v) 1180°C. A typical experiment involves the measurement of the rate of desorption as a function of surface morphology, composition, and temperature. These results suggest that desorption from the porous matrix is limited by strong capillary forces and can be overcome by external factors such as temperature. The chemical composition of the porous Si surface also plays a role in desorption and can increase or lower desorption rates. The clearest difference in diphenylamine desorption behavior is detected between the freshly prepared porous Si surface and porous Si samples rapid thermally oxidized at 600 and 1180°C. © 1999 The Electrochemical Society. All rights reserved.
336: Ventilatory Inefficiency Is Associated with Right Ventricular Dysfunction in Patients with Advanced Cardiomyopathy

Ventilatory Inefficiency Is Associated with Right Ventricular Dysfunction in Patients with Advanced Cardiomyopathy A.B. Methvin, S.E. Wiegers, A. Emmi, P.R. Forfia, Heart Failure and Transplant Center, University of Pennsylvania, Philadelphia, PA; University of Pennsylvania School of Medicine, Philadelphia, PA; Cardiovascular Division, Echocardiographic Laboratory, University of Pennsylvania, Philadelphia, PA
Childhood Victimization and its Impact on Coping Behaviors for Victims of Intimate Partner Violence

This study explores patterns of victimization and coping in a conservative Christian denomination. Four types of coping behaviors are identified: informal coping, professional help-seeking, negative coping and crisis outreach. While religious behaviors are less influential than expected for this particular population, current victimization and childhood victimization play a significant role in establishing a model of coping and help-seeking for intimate partner violence (IPV) survivors in faith communities. Childhood victimization acts as an aggravating factor, predicting negative coping with IPV. At the same time, childhood victimization significantly increases the likelihood of seeking professional help. The study adds to the body of knowledge by contributing to a better understanding of the impact of childhood victimization on coping and help-seeking.
Desulfurization of organosulfur compounds with lithium and sodium

Dibenzothiophene is desulfurized under relatively mild conditions by metallic sodium in tetradecane at 150 °C in 24 h to give biphenyl in 99% yield after methanol/H2O work up according to GC analys...
Computer simulation of the formation of planetary systems

Abstract One of the many hypotheses about the formation of the solar system postulates that the planets were formed by the aggregation of particulate matter within a cloud of dust and gas surrounding the newly-formed sun. A test of the validity of one version of this hypothesis was obtained in a computerized Monte Carlo simulation of the process. In the model used, nuclei are “injected” into the cloud one at a time, on elliptical orbits. The dimensions of the semimajor axis and the eccentricity of the orbit of each nucleus are determined by using random numbers. As the nuclei orbit within the cloud they grow by aggregation and gradually sweep out dust-free annular lanes. If they grow larger than a specified critical mass they can begin to accumulate gas from the cloud as well. If the orbit of a planet comes inside a certain interaction distance from a planet that was formed earlier, or if the orbits cross one another, the two bodies coalesce to form a single, more massive planet which may then continue to grow by aggregation. The process of injecting nuclei is continued until all the dust has been swept from the system. At this point the run is terminated and the machine output displays the masses and orbital parameters of the planets remaining in the final configuration. Each planetary system produced by using a different random number sequence is unique. However, all the systems so produced share the major regular features of our solar system. The orbital spacings have patterns of regularity suggestive of “Bode's law.” The innermost planets are small rocky bodies; the midrange planets are large gaseous bodies; the outermost planets are generally small. The general patern of planetary mass distribution is similar to that in our solar system with masses ranging from less than that of Mercury to greater than Jupiter's.
Algorithmic approach to solid adnexal masses and their mimics: utilization of anatomic relationships and imaging features to facilitate diagnosis

Solid adnexal masses, while less common than their cystic counterparts, may present a challenge for radiologists given the wide range of histologic entities that occur in this region. Pelvic masses, especially when large, can seem overwhelming at first but application of an algorithmic approach allows for more confident assessment. This approach focuses first on the use of anatomic relationships and interactions of various pelvic structures to localize the mass’ origin. For instance, the directionality of ureteral displacement can suggest if a mass is intra or extraperitoneal. Then, key discriminating imaging features, such as the presence of fat, hypervascularity, or low T2 signal on magnetic resonance imaging (MRI) can be applied to further narrow the list of diagnostic possibilities. Entities such as leiomyomas, nerve sheath tumors, congenital uterine anomalies, and vascular abnormalities (ovarian torsion or iliac vessel aneurysm) in particular are often accurately characterized with sonography and/or MRI. For solid adnexal masses in which a definitive diagnosis by imaging is not reached, information germane to clinicians regarding further management can still be provided, principally with regard to surgical vs. nonsurgical treatment.
Equivalence of the combinatorial and the classical definitions of Schur functions

On donne une breve demonstration elementaire de l'equivalence des definitions combinatoire et classique des fonctions de Schur
How Important Is Air–Sea Coupling in ENSO and MJO Evolution?

Abstract The effect of air–sea coupling on tropical climate variability is investigated in a coupled linear inverse model (LIM) derived from the simultaneous and 6-day lag covariances of observed 7-day running mean departures from the annual cycle. The model predicts the covariances at all other lags. The predicted and observed lag covariances, as well as the associated power spectra, are generally found to agree within sampling uncertainty. This validates the LIM’s basic premise that beyond daily time scales, the evolution of tropical atmospheric and oceanic anomalies is effectively linear and stochastically driven. It also justifies a linear diagnosis of air–sea coupling in the system. The results show that air–sea coupling has a very small effect on subseasonal atmospheric variability. It has much larger effects on longer-term variability, in both the atmosphere and the ocean, including greatly increasing the amplitude of ENSO and lengthening its dominant period from 2 to 4 years. Consistent with these...
Logratio linear modelling of hydraulic geometry using indices of flow resistance as covariates

Abstract The exponents of hydraulic geometry relations are unit-sum constrained (i.e., a composition), thus, a class of statistical methods called compositional data analysis must be employed to obviate the problem of spurious correlation. One of these methods, logratio linear modelling, is capable of establishing either linear or non-linear functional dependency between a composition (e.g., hydraulic geometry exponents) and a covariate. In our study, logratio linear modelling of data from the literature did not establish correlations between at-a-station hydraulic geometry and median grain size (d50) of the bed material, stream roughness, nor drag resistance. The lack of a correlation between at-a-station hydraulic geometry and bed grain size is expected in streams where roughness is dominated by planform characteristics, vegetation elements, macroscale bar features, channel obstructions, or bedforms. The use of d84 in the Prandtl-von Karman “law of the wall” equation and in the Keulegan resistance equation, however, suggests that d84 might have been a more appropriate parameter to use than d50. The lack of a correlation between at-a-station hydraulic geometry and stream roughness (or drag resistance) is expected in streams where roughness elements become rapidly “drowned” at higher discharges. Hydraulic geometry, however, was shown to be a function of the rate at which stream roughness varies with discharge. Thus, to understand the complex interactions within fluvial systems, geomorphologists should examine the rates of change of stream parameters such as drag resistance, Manning's roughness coefficient, the Darcy-Weisbach friction factor, and grain size indices, in addition to the stream parameters themselves.
Enhanced chemical reactions of oxygen at grain boundaries in polycrystalline graphene

Abstract Oxygen adatoms on graphene and their potential reactions have been studied extensively as a way to modify and control the material’s properties. Here, we report first-principles calculations and Kinetic Monte Carlo simulations to describe oxygen binding, diffusion, and reactions on graphene in the presence of grain boundaries. We show that the defects attract and accumulate oxygen caused by the local strain. Moreover, we find that the reaction of a three-atom oxygen cluster, which consumes carbon atoms and creates vacancies in graphene, has a lower reaction barrier at grain boundaries than that on pristine graphene. Kinetic Monte Carlo simulations suggest that the dynamics of oxygen on graphene is controlled by two processes, oxygen reaction and migration, which depend on temperature and oxygen coverage. Because of the comparable activation barrier for both processes, etching at grain boundaries and the pristine region occurs simultaneously.
Comparisons of the Vocabulary Scores and IQs on the Wechsler Intelligence Scale for Children—III and the Peabody Picture Vocabulary Test—Revised:

The Wechsler Intelligence Scale for Children—III and the Peabody Picture Vocabulary Test—Revised were given to 33 children (15 boys, 18 girls) who were enrolled in Grades 3, 4, and 5. The statistic...
The cancer biology of whole-chromosome instability

One form of chromosome instability (CIN), the recurrent missegregation of whole chromosomes during cell division (W-CIN), leads to aneuploidy. Although W-CIN is a hallmark of most cancers, mutations in genes involved in chromosome segregation are exceedingly rare. We discuss an oncogene-induced mitotic stress model that provides a mechanistic framework to explain this paradox. We also review the tumor-promoting and tumor-suppressing consequences of W-CIN. Importantly, we do this in the context of cancer as a complex systemic disease, rather than as a simple linearly progressing disorder that arises from a single abnormal cell population. Accordingly, we highlight the often neglected effects of W-CIN on key non-cell-autonomous entities, such as the immune system and the tumor microenvironment. Distinct tissue-specific susceptibilities to W-CIN-induced tumorigenesis and the clinical implications of W-CIN are also discussed.
Data-swapping: A technique for disclosure control

Abstract This paper describes data-swapping as an approach to disclosure control for statistical databases. Data-swapping is a data transformation technique where the underlying statistics of the data are preserved. It can be used as a basis for microdata release or to justify the release of tabulations.
Applications and testing of the LSCAD system

The lightweight standoff chemical agent detector (LSCAD) is an infrared Michelson interferometer operating in the 8 - 13 micron band and is designed primarily for military contamination avoidance and early warning applications. The system is designed to be operated autonomously from a vehicle while on the move and provide 360 degree coverage. The first group of prototypes were delivered in 1994 and have undergone integration into several platforms including the HMMWV, the M2 Bradley Fighting Vehicle, the M109 self- propelled Howitzer and the Pioneer and Hurricane unmanned air vehicles (UAVs). Additional vehicles and platforms are planned. To meet the restrictions of military applications, the prototype interferometer subsystem has a weight of about 10 lbs and is approximately 0.20 cu fit in size. The full system size and weight depends upon the particular platform and its operational requirements. LSCAD employs onboard instrument control, data collection, analysis and target detection decision software, all of which are critical to real-time operation. The hardware, software, and test results are discussed.
Prolate-Oblate Difference and its Effect on Energy Levels and Quadrupole Moments

From the microscopic calculation for the W, Os, and Pt nuclei, we obtain semiquantitative relations among the prolate-oblate difference of the potential energy of deformation, the ${{2}_{\ensuremath{\gamma}}}^{+}$ and ${4}^{+}$ level splitting, and the static quadrupole moment ${{Q}_{2}}^{+}$. These relations are applied to $^{24}\mathrm{Mg}$, $^{56}\mathrm{Fe}$, $^{110}\mathrm{Cd}$, and $^{152}\mathrm{Sm}$. The important role of the $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ dependence of the mass parameters is demonstrated.
MusEEGk: a brain computer musical interface

We present a novel integration of a brain-computer interface (BCI) with a music step sequencer composition program. Previous BCIs that utilize EEG data to form music provide users little control over the final composition or do not provide enough feedback. Our interface allows a user to create and modify a melody in real time and provides continuous aural and visual feedback to the user, thus affording them a controllable means to achieve creative expression.
On Returning from Our Agricultural Babel

SAMUEL BECKETT'S play, Breath, consists of a stage, and on it a pile of junk. The curtains part; there is a giant sound of a person inhaling, punctuated by a baby's struggled cry, then the giant exhalation of one dying. The curtains close; the scene is repeated several times; that is all; that is the message. The anguished world of Beckett is the quintessence of a universe organized along the double polarity of the necessity to say something and the impossibility of saying it. The paradox of the artist incapable of not writing, not speaking, not struggling to communicate his "truth," despite the apparent absurdity of existence, might be likened to that of the modern economist. It attests to a striving for significance in the face of irrationality in the world and among men. It also embodies a hopesometimes in a desperate gamble-to use words and symbols to escape a meaninglessness that surrounds us even though our roles testify to some peculiar meaninglessness. The situation Socrates faced in Plato's Phaedo was analogous to Beckett's and to ours: there was evil in the souls of men because there were conflicting communications. Ordinary words had many different meanings, were distorted and diverted from the plain and simple use that people believed them to have. We here today cannot be indifferent to the communication problem. Language has committed American agriculture to a world that does not exist. Between the agricultural word-vision of the world and the reality of the world extends a wide chasm. Our profession is filled with sophists; but instead of praying for a modern Socrates to save us, I call on all agricultural economists to clarify an agrarian language, to update our own dictionary, and to make significant the link between
Mechanisms of monovalent cation action in enzyme catalysis: the first stage of the tryptophan synthase beta-reaction.

The tryptophan synthase bienzyme complex is activated and regulated by the allosteric action of monovalent cations (MVCs). The kinetic dissection of the first stage (stage I) in the β-reaction of tryptophan synthase, the reaction of l-serine with pyridoxal 5‘-phosphate at the β-site to give the α-aminoacrylate Schiff base intermediate, E(A-A), is here examined in the absence and presence of MVCs. This analysis reveals which of the individual steps are greatly affected in stage I and how the ground states and transition states are affected by MVCs. Kinetic studies in combination with a detailed relaxation kinetic analysis to determine the specific rate constants for the conversion of the l-Ser external aldimine, E(Aex1), to E(A-A) show that the primary kinetic isotope effect for proton abstraction from Cα of the E(Aex1) species changes from 4.0 ± 0.4 in the absence of MVCs to a value of 5.9 ± 0.5 in the presence of Na+, indicating that the nature of the transition state for this C−H scission is significant...
Familial versus sporadic breast cancer.

BACKGROUND:Studies comparing patients with familial and sporadic breast cancer have indicated that a family history of the disease can increase a woman's risk for having the disease twofold to threefold and that patients with familial breast cancer have a younger age at diagnosis and have a higher frequency of bilateral disease than those with sporadic breast cancer. Also, at least four types of breast cancers have been shown to be inherited. These findings led to the hypothesis that familial and sporadic breast cancer are the consequence of two biologically distinct mechanisms. METHODS:A two-step mutation model proposed by Knudson in 1971 provides a link between the molecular mechanisms underlying familial and sporadic breast cancer. According to this model, both cancers involve the same genomic change in homologous chromosomes. The only difference is that the first mutation is inherited and the second is somatic in familial cancer, whereas in sporadic cancer both mutations are somatic. Mutation is used in a broad sense and refers to either a point mutation at a specific locus or the loss of a locus by deletion or nondysfunction. RESULTS:This model has been shown to apply to several childhood and adult cancers, including breast cancer. Based on this model, patients with familial breast cancer will have their disease earlier in life and will have more bilateral cancer than patients with sporadic breast cancer. Moreover, the two types of patients should show no differences in clinicopathologic characteristics because both types involve the same genomic change and the pathogenesis of both types should be the same, thus arguing against the early hypothesis that patients with familial and sporadic breast cancer are the consequence of biologically distinct mechanisms. CONCLUSIONS:Breast cancer appears to involve the cumulative effect of several genetic lesions involving the activation of oncogenes and the inactivation of tumor-suppressor genes. Which genes are involved specifically as causative factors of breast cancer (the inherited gene or genes) and which are important somatically in its continued development and progression (oncogenes and tumor-suppressor genes) requires additional study.
A NOTE ON ESTIMATING THE DEMAND FOR DIESEL FUEL BY FARMERS IN THE UNITED STATES

This study is concerned with the impact that inaccuracy in the measurement of the dependent variable and one or more of the independent variables has on the price elasticity of demand estimate. Two diagnostics - the regression coefficient bounds and the bias correction factor - are introduced to assess the effect that such measurement errors have on the estimated coefficientsof demand relationships. In considering the demand for diesel fuel per acre by farmers in the United States, both the quantity demanded and the price data available contain measurement error. The regression coefficient bounds diagnostic is used to indicate a range over which the true price responsiveness of farmers to changes in energy prices lies. The results suggest that each 1 percent increase (decrease) in the price of energy will result in between a 1.15 and 0.26 percent decrease (increase) in the quantity of diesel fuel demanded. The bias correction factor is
Update on the Pathogenesis and Management of Pouchitis

Pouchitis is an inflammatory complication after restorative proctocolectomy and ileal pouch-anal anastomosis (IPAA). IPAA is the surgical treatment of choice in patients with ulcerative colitis (UC) who require colectomy. Initial episodes of acute pouchitis generally respond to antibiotics but significant numbers of cases eventually become dependent on or refractory to antibiotics. Management of chronic antibiotic refractory pouchitis is challenging and can ultimately lead to pouch failure. The etiopathogenesis is unknown though recent studies have implicated bacterial dysbiosis of the pouch microbiota, NOD2 polymorphism, and Clostridium difficile infection in the development of severe pouchitis. Early identification of risk factors can help in tailoring therapy and reducing cases of chronic pouchitis.
RACTERISTICS OF HUMAN MEDULLOBLASTOMA CELL LINE TE‐671 UNDER DIFFERENT GROWTH CONDITIONS IN VITRO: A MORPHOLOGICAL AND IMMUNOHISTOCHEMICAL STUDY

Characteristics of human medulloblastoma cell line TE-671 under different growth conditions in vitro: a morphological and immunohistochemical study The human medulloblastoma cell line, TE-671, was studied in vitro both in monolayer culture and in a three-dimensional culture system using gelfoam as the supporting matrix. Flow cytometry studies of cells grown in monolayer culture revealed a unimodal, tetraploid DNA content. Most cells in both in vitro systems contained neuron-specific enolase (NSE), actin, and tubulin, while only occasional cells or cell clusters contained the 68 000 molecular weight subunit of neurofilaments (NF mol. wt 68 000) or microtubule-associated protein 2 (MAP-2). In monolayer culture, long cellular processes containing NSE, NF mol. wt 68 000 and MAP-2, which were present at 2 days, were nearly absent by 7 days. All antigens were present at 4 days in the organ culture system; by 72 days, cells still stained positively for NF mol. wt 68000 and MAP-2, but staining for NSE, actin, and β-tubulin was diminished as compared to 4 days. Retinoic acid (RA) in the 13-cis isomer form at 10-6 M was applied to monolayer cultures at day 1 for 6 days and to gelfoam cultures at day 1 for 28 days. RA did not significantly alter cell proliferation up to 7 days in vitro and did not appreciably affect cellular expression of NSE, NF mol. wt 68000, MAP-2, β-tubulin, or actin in either system. By electron microscopy, most cells grown under different culture conditions with or without RA treatment appeared to be undifferentiated and polygonal, with occasional cytoplasmic annulate lamellae. The immunohistochemical and ultrastructural features reported indicate that the TE-671 medulloblastoma line is composed primarily of primitive neuroepithelial cells with a limited potential for neuronal differentiation. This differentiation was not promoted by RA or by an in vitro system known to favour differentiation in a number of human and animal nervous system tumours. The findings suggest that the cells of the TE-671 line lack either receptors for retinoic acid or the capacity to respond to bound retinoic acid.
Electrical and structural properties of some ternary chalcogenides of titanium

Abstract Electrical resistivity and Seebeck coefficient measurements have shown the six compounds M Ti 2 X 4 ( M = Fe,Co,Ni; X = S,Se) to exhibit metallic behavior. This is accounted for on the basis of direct Ti-Ti overlap. At room temperature, these compounds all have the monoclinic Cr 3 S 4 -type structure (space group 12/m), which is characterized by ordered vacancies in alternate metal layers. A reversible temperature-dependent transformation to a disordered trigonal structure (space group P3ml) has been shown to occur for NiTi 2 S 4 and NiTi 2 Se 4 at approximately 340°K. The resistivity plots for both compounds show an increase in the resistivity at approximately the same temperature. This change in resistivity is a result of the disordering of the vacancies in the structure.
Degenerative lumbar spine disorders in gradient refocused echo axial magnetic resonance images

The axial images of 58 lumbar disks having degenerative disorders imaged by gradient refocused echo (GRE) and spin echo (SE) magnetic resonance imaging (MRI) pulse sequences at high field strength were compared for diagnostic quality. The vacuum phenomenon, calcified disk, and bony hypertrophic changes were better demonstrated by GRE images than by SE images due to magnetic susceptibility effect. Axial GRE images are therefore useful adjuncts to SE images for effective MRI of degenerative lumbar spine disorders at high field strength.
Interfacial Thermal Stresses in Layered Structures: The Stepped Edge Problem

The intense, localized stress field produced by a temperature load in a multilayered structure may be significantly affected by the local geometry of the free edge. We examine here the stepped edge problem associated with bonding an elastic layer (silicon chip) to a single or multilayer substrate with a slightly larger length. Stress functions are introduced in various rectangular regions and the continuity of tractions are enforced across all inter-region boundaries. Furthermore, continuity of displacements is enforced across the junction of the two segments of the base laminate. The analysis results indicate that even a minute protrusion of the edge of the base laminate relative to the attached chip may cause significant changes in the peeling and shearing stresses in the end region of the interface.
Nurse versus machine: slaves or masters of technology?

As the millennium approaches nurses are challenged to reflect on the evolving role of technology on the profession. A preview of the technologies coming to the clinical arena in the not-so-dis-tant future is provided. Eight guidelines for wise technology integration are offered to assist providers in appropriately using technology while preserving humanity in an increasingly high-technology world. JOGNN, 28, 433–441; 1999.
Evaluation of Four Sampling Methods for Determining Exposure of Children to Lead-Contaminated Household Dust☆☆☆

Abstract Childhood exposure to lead has been demonstrated to result in health effects and lead-contaminated household dust is a primary exposure source. There is a need to establish reliable methods for sampling surfaces to determine levels of lead contamination. Three vacuums (HVS3, GS80, and MVM) and one wipe method were evaluated for the collection of household floor dust under field sampling conditions within a Superfund site and demographically similar control area. Side-by-side floor samples were taken from three locations within 41 randomly selected households between August and September 1995: a child's bedroom, primary play area, and primary entrance. Analysis was performed to assess the relative collection performance of each sampler, spatial distribution of lead within a household, and correlation of lead loading with observed blood lead level, and to determine if discrete or composites samples were more predictive of blood lead levels. Approximately 90% of the floor surfaces were carpeted. The rank order of sampling methods from greatest to lowest collection efficiency was HVS3 > GS80 > wipe > MVM. The HVS3 had the highest level of precision (CV=0.05), with the GS80 and wipe precisions 0.48 and 0.053, respectively. Lead loadings for samples collected in bedrooms and living areas and composite samples using the HVS3 and wipe methods were significantly correlated with blood lead levels. Correlations between blood lead levels and composite samples were stronger for the HVS3 ( R 2 =0.33, P =0.003) and wipe ( R 2 =0.25, P =0.002) methods than the respective discrete samples. Regression analysis indicated that a blood lead level of 10 μg/dl corresponds to a carpet wipe sample geometric mean of 68 μg/ft 2 . For ongoing public health purposes, such as screening and clearance testing, use of the wipe sampling method is the most appropriate. This investigation supports findings by others that the present HUD risk levels for lead in floor wipe samples may not be adequate for reducing children's blood lead levels below 10 μg/dl.
Deletion of tetraspanin Cd151 results in decreased pathologic angiogenesis in vivo and in vitro

Tetraspanin protein CD151 is abundant on endothelial cells. To determine whether CD151 affects angiogenesis, Cd151-null mice were prepared. Cd151-null mice showed no vascular defects during normal development or during neonatal oxygen-induced retinopathy. However, Cd151-null mice showed impaired pathologic angiogenesis in other in vivo assays (Matrigel plug, corneal micropocket, tumor implantation) and in the ex vivo aortic ring assay. Cd151-null mouse lung endothelial cells (MLECs) showed normal adhesion and proliferation, but marked alterations in vitro, in assays relevant to angiogenesis (migration, spreading, invasion, Matrigel contraction, tube and cable formation, spheroid sprouting). Consistent with these functional impairments, and with the close, preferential association of CD151 with laminin-binding integrins, Cd151-null MLECs also showed selective signaling defects, particularly on laminin substrate. Adhesion-dependent activation of PKB/c-Akt, e-NOS, Rac, and Cdc42 was diminished, but Raf, ERK, p38 MAP kinase, FAK, and Src were unaltered. In Cd151-null MLECs, connections were disrupted between laminin-binding integrins and at least 5 other proteins. In conclusion, CD151 modulates molecular organization of laminin-binding integrins, thereby supporting secondary (ie, after cell adhesion) functions of endothelial cells, which are needed for some types of pathologic angiogenesis in vivo. Selective effects of CD151 on pathologic angiogenesis make it a potentially useful target for anticancer therapy.
Object localization in procedural programs: a graph-based approach

Maintenance of legacy systems is a laborious, error-prone task. It is often difficult to define encapsulated components in procedural programs. We define a comprehensive process for re-engineering procedural, legacy code to an object-oriented architecture. The process is based on a program representation graph, called a statement dependence graph. The process includes a technique to recognize potential object hierarchies, state variables and operations. Procedures are partitioned into operations by analyzing variable use-def chains. The statement dependence graph is restructured by merging cohesive parts of the graph to produce a restructured graph. From the restructured graph, we identify hierarchies of objects. The process to encapsulate the objects includes streamlining the interfaces. Copyright © 2000 John Wiley & Sons, Ltd.
The Role of Markets and Governments in Helping Society Adapt to a Changing Climate

This paper provides an economic perspective of adaptation to climate change. The paper specifically examines the role of markets and government in efficient adaptation responses. For adaptations to be efficient, the benefits from following adaptations must exceed the costs. For private market goods, market actors will follow this principle in their own interest. For public goods, governments must take on this responsibility. Governments must also be careful to design institutions that encourage efficiency or they could inadvertently increase the damages from climate change. Finally, although in a few cases actors must anticipate climate changes far into the future, generally it is best to learn and then act with respect to adaptation.
Computed tomography, ultrasonography, and endoscopic retrograde cholangiopancreatography in the diagnosis of pancreatic disease: a comparative study.

A prospective study was performed comparing the sensitivity of computed tomography, ultrasonography, and endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of pancreatic disease. Forty patients with suspected pancreatic carcinoma, acute recurrent or chronic pancreatitis, and/ or jaundice were studied. CT was the most sensitive study in evaluation of pancreatitis. ERCP was most accurate in evaluation of pancreatic malignancy. Ultrasonography was the least sensitive method in detecting pancreatic disease and dilatation of the extrahepatic biliary ducts.
Tuba stimulates intracellular N-WASP-dependent actin assembly

Tuba is a multidomain scaffolding protein that links cytoskeletal dynamics and membrane trafficking pathways. The N-terminus of Tuba binds dynamin1, and the C-terminus contains domains that can interact with signaling pathways and cytoskeletal regulatory elements. We investigated Tuba localization, distribution and function in B16 melanoma cells. Tuba overexpression stimulated dorsal ruffles that occurred independently of dynamin function. Tuba expression induced actin-driven motility of small puncta that required the C-terminal SH3, GEF and BAR domains. Additionally, Tuba was recruited to lipid vesicles generated by overexpression of phosphatidylinositol-4-phosphate 5-kinase type Iα (PIP5Kα), localizing prominently to the head of the comets and at lower levels along the actin tail. We propose that Tuba facilitates dorsal ruffling of melanoma cells through direct interaction with actin-regulatory proteins and the recruitment of signaling molecules to lipid microdomains for the coordinated assembly of a cytoskeletal network. Knockdown of Tuba by RNA interference (RNAi) attenuated PIP5Kα-generated comet formation and the invasive behavior of B16 cells, implying that Tuba function is required for certain aspects of these processes. These results suggest first that Tuba-stimulated dorsal ruffling might represent a novel mechanism for the coordination of N-WASP-dependent cytoskeletal rearrangements and second that Tuba function is implicated in motility processes.
Membrane receptors for steroid hormones: Signal transduction and physiological significance

Membrane receptors for steroid hormones affect signaling pathways that modulate nuclear function, influence neuronal activity, ion flow, and the circulatory system. Indeed, 'new' steroid hormones have been identified by their interaction with membrane-initiated signaling systems. A brief summary of the FASEB Summer Research Conference devoted to these topics is presented in this mini-review. In addition, attendees of the meeting propose introduction of the following terminology: membrane-initiated steroid signaling (MISS) and nuclear-initiated steroid signaling (NISS) to replace more inaccurate terms in current use.
Bernstein mode quasi-optical gyroklystron

The performance of a quasi-optical cyclotron harmonic gyroklystron operating on electron Bernstein modes is investigated. An expression for the linear power output has been derived. It is found that, for high order cyclotron harmonic operation, a gyroklystron involving the Bernstein modes has higher linear efficiency than a corresponding gyroklystron based on electromagnetic interactions alone.
Social problem-solving in a revolutionary setting: Nicaragua's pesticide policy reforms.

Pesticide related health problems and environmental contamination have plagued the Third World for several decades. This study explores the efforts to resolve pesticide problems within the context of the Nicaraguan revolution. Through a case study of Nicaragua's pesticide policy reforms the opportunities afforded by Third World revolutions to address specific social problems are analyzed. The study then explores the array of obstacles to implementation of such reforms generated by political and military opposition to revolutionary change and concludes with an assessment of prospects for social problem-solving in a revolutionary setting.