cssi/SciSciGPT-SciSciNet huggingface dataset:
Lateral migration radiography application to land mine detection, confirmation and classification

Lateral migration radiography (LMR) employs scattered photons to acquire detailed images of covered objects. images of plastic encased real mines buried in soil using LMR have shown dramatic differences compared to images generated using simulated mines. The major characteristic that enables the discernibility of land mines to the degree of actual type identification is the presence of voids (air volumes) required for the operation of the fuse assembly or for blast direction control. Air volumes greatly modify the detected field of both once and multiple-scattered photons. The LMR system consists of an x-ray generator and two uncollimated detectors positioned to detect once- scattered photons and two collimated detectors designed to detect primarily multiple-scattered photons. The x-ray generator is located in the gap between symmetrically arranged detectors; the collimated x-ray beam typically has a spot size of 1.5x 1.5 cm with perpendicular incidence on the soil surface. The optimal x-ray spectra for land mine detection with the LMR system range from 130 to 180 kVp with mean x-ray energies of from around 40 to 60 keV. Air volumes modify both exit paths and the position of first-scatter events; they also modify the migration paths of multiple-scattered photons, thus producing different images in the two detector types. The burial mode (below surface or laid on the surface) of the land mine can also be discerned by LMR due to a shadowing effect seen for surfaced-laid land mines. The presence of even a minute amount of metal in the land mine also aids in discerning the mine, because metal produces a signal decrease in both types of detectors. Monte Carlo calculations are performed with the MCNp code to obtain an understanding of the details of the photon lateral migration process. Images generated from these Monte Carlo calculations are in agreement with the experimental measurements. The real mine images confirm that LMR is capable not only of mine detection, but also of mine identification.
Breast masses: mammographic evaluation.

The systematic mammographic evaluation of a breast mass involves independent assessments of its size, location, density, shape, clarity of margins, and interval change from prior examination. Additional fine-detail mammograms should be obtained to facilitate this analysis, especially when an equivocal interpretation is planned. Definitively benign masses (those localized to the skin, of fat density, or of mixed density) will not require more attention. Among the remaining water-density lesions, those that have an even slightly stellate appearance should be considered suspicious for malignancy; virtually all of them will undergo biopsy. Well-circumscribed masses should next be evaluated by aspiration or US examination to establish or exclude the diagnosis of simple benign cyst. Only solid and indeterminate lesions will require further evaluation, with the ultimate decision for biopsy versus mammographic follow-up depending on the probability of malignancy determined by the combination of mammographic and p...
Opinion: Increasing Learning through Writing in Quantitative (and Computer) Courses

SUMMARY The title of this paper might cause a culture shock among many. It would not be an exaggeration to say that among many of my colleagues in the academic community, the expression ‘writing in quantitative courses’ would be considered a contradiction in terms. Popularly, the goals and methods of composition courses and those of quantitative courses are perceived to be mutually exclusive.** Stereotypes abound regarding the methods of discourse and the practitioners of these two disciplines. Some examples are: ‘Those who write do not like the cold logic of equations and numbers’ and ‘The quantitative types are uncomfortable with the vagueness and wordiness of the literary types.’ Some of these stereotypes are not altogether without justification. The ‘quantitative’ types talk in a language where every third word is in mathematese, replete with terms such as ‘mean’, ‘median’, ‘rank’, ‘correlation’, ‘probability’ or worse! The archetypal quantitative person is the mathematics professor who fills the blac...
Exploiting the link between CI and the coupled cluster model. estimates for cluster energies and wavefunctions and a means for the rapid determination of CCD wavefunctions

Abstract Simple means for choosing initial-guess double substitution coupled cluster (CCD) wavefunctions and energies on the basis of double substitution configuration interaction (CID) results can lead to rapid iterative solution of the CCd wavefunction. This is because the importance of doubly substituted configurations in a CID wavefunction seems to exhibit a simple, primary relation to their importance in a CCD wavefunction.
Neoliberal Reform and Health Dilemmas

In this article, I trace the links among neoliberalism, regional ecological decline, and the dynamics of therapeutic processes in rural Senegal. By focusing on illness management in a small rural community, the article explores how economic reform is mediated by existing social structures, and how household social organization in turn influences therapeutic decision making. The illness episodes relayed here demonstrate how the acute economic and social crisis facing the Ganjool region becomes written on the bodies of young men, and how the fault lines of gender and generation shape illness experiences. These narratives also illuminate the tremendous discrepancy between the lived realities of sickness and death, and the idealized models of health participation and empowerment envisioned by the state. Rather than “neoliberal subjects” who behave as rational economic actors, men and women coping with illness are social beings embedded in fields of power characterized by highly stratified household social relations.
Effects of dopamine receptor antagonists (D1 and D2) on the demand for smoked cocaine base in rhesus monkeys

Rationale: Previous studies suggest that dopamine antagonists may reduce the reinforcing effects of cocaine. However, the effects of these antagonists on the demand for smoked cocaine base have not been quantified. Objectives: To evaluate the effects of selective D1 (SCH 23390) and D2 (raclopride) dopamine receptor antagonists on the demand for smoked cocaine base in rhesus monkeys using a behavioral economic analysis. Methods: Six rhesus monkeys were trained to self-administer smoked cocaine base (1.0 mg/kg/delivery) under chained fixed-ratio (FR) schedules (FR64, 128, 256, 512, 1024 or 2048 for lever presses and FR5 for inhalations) during daily 4-h sessions. A maximum of ten smoke deliveries were available. After 5 days of stable behavior at each FR, SCH 23390 (0.01 and 0.056 mg/kg) or raclopride (0.03 and 0.056 mg/kg) were injected intramuscularly, before each session, for 3 consecutive days. Results: Pretreatment with both antagonists dose-dependently reduced cocaine intake across most FR values tested; however, the decrease in consumption was greater at the higher unit prices than at the lower unit prices. A statistical estimate of the price (FR) at which maximum responding occurred (Pmax) was decreased during drug pretreatment, indicating weakened reinforcing effectiveness of cocaine. Conclusions: These data suggest that both antagonists reduce the reinforcing effectiveness of smoked cocaine base, and they have a greater effect on cocaine consumption at higher FR values.
Genetic variability at the pig SLA complex in U.S. breeds of pigs.

Summary Lymphocytes from 90 mature pigs and 548 growing pigs from 6.5 litters were screened with cytotoxic antibodies against swine lymphocyte antigens. Pigs included in the survey were from the Chester White, Duroc, Hampshire, Landrace and Yorkshire breeds. Significant differences between breeds were found in the frequency of the three haplotypes tested. Such differences may provide the genetic variability needed to determine associations between disease susceptibility and the pig's major histocompatibility gene complex.
PROPOSED EVALUATION OF BASE MATERIALS FOR DRAINABILITY

Base materials are normally selected to achieve maximum density and possess sufficient stiffness and strength to carry traffic loads. Long-time concerns about the poor drainability of these materials have recently prompted the highway materials community to address this problem. The main objectives of the research reported here were to evaluate the drainability of base materials used in Texas and to propose and evaluate modified materials that could improve drainability while maintaining stiffness and strength levels. Drainability is evaluated on the basis of the permeability coefficient and water retention tests. The water retention test was found to be a much easier test to perform than the permeability test and is believed to be much more directly related to the drainability of the compacted base than the permeability coefficient. Alternative materials evaluated consisted of open-graded bases and cement-stabilized gravel. The results of the present study indicate that cement-stabilized gravel is the best alternative to achieve high stiffness and strength and at the same time minimize water retention capacity.
Building Knowledge Management Systems

Why do some organizations prosper and grow while others struggle? There are a variety of interrelated factors that determine the answer to such a complex question, and these factors differ for organizations in different places and at different times. However, one key ability that is common to all successful organizations is effective creation of relevant business knowledge and the timely dissemination of that knowledge to those members of the organization who need it.
Regions of validity of the (d,p) coulomb stripping approximation

The validity of the Coulomb stripping approximation for (d,p) reactions was investigated numerically for six targets ranging from 16O to 238U. The investigation involved finding the region in (Ed,Q) space where DWBA calculations that include nuclear optical-model potentials yield agreement with calculations that include only the Coulomb potentials. For nuclei between 48Ca and 238U the boundary between valid and non-valid Coulomb stripping was found to have an Ed dependence proportional to Z and a Q dependence proportional to ZA13; and furthermore, this boundary can be approximated by a straight line which, for 90Zr(d,p)91Zr, has the intercepts Ed = 4.2 MeV and Q = 5.2 MeV.
A Tissue Phantom Model for Training Residents in Ultrasound-guided Liver Biopsy

Rationale and Objectives The apprenticeship model for training of percutaneous liver biopsy has limitations, and costs of commercially available simulation models can be prohibitive. We created an inexpensive tissue phantom for liver biopsy simulation and evaluated the utility of this model for training radiology residents. Materials and Methods A bovine–porcine tissue phantom was devised as a simulation model and consisted of bovine liver with a porcine rib layer and inserted pimento olives simulating target lesions. Training sessions (a 20-minute didactic lecture and a 90-minute practice session) were offered to all residents in a diagnostic radiology residency. Effect of training was assessed by questionnaire before and after training. Level of knowledge of topics covered in the didactic session, confidence in technical skills, and anxiety level were evaluated on a five-point scale (1, poor to 5, excellent). Results Thirty-five of 38 residents received training on the models (∼$40). Mean reported value score for training was 4.88/5. Improvement was greatest for knowledge of technique (2.3–4.1/5, P P P P n = 21) had significantly greater increases in all categories than residents with prior experience ( n = 14), except for knowledge about obtaining informed consent and anxiety levels. Conclusions Utilization of an inexpensively created bovine/porcine liver biopsy simulation model was well perceived by radiology residents and can be used as an educational tool during residency.
Gel Electrophoresis in the Study of Pneumoconioses

Abstract Proteins as well as other macromolecular constituents of biological tissue may be separated by electrophoresis on starch gel, and the resulting gel samples may be stained for a variety of substances including protein, mucoid, and enzymes such as esterases, phosphatases, and dehydrogenases. The variability of these patterns from serum, erythrocyte, lung, and lymph node specimens is correctable to previous inhalation exposure of the host to toxic substances such as beryllium compounds, as well as to aerosols of radioisotopes. General urban air pollution, when compared to filtered air, caused no consistent effect. Development of pulmonary pathology sustained in response to such exposures is evidenced by disappearance or de novo appearance of certain isozyme bands. Applicability of the method to the study of the pathogenesis, toxicological mechanism, and diagnosis of the pneumoconioses appears to have considerable potential.
A decomposition theorem for h-cobordant smooth simply-connected compact 4-manifolds.

Theorem. Let M and N be smooth ;h -cobordant compact 1-connected 4-manifolds. There exist decompositions M = M0 [ M1 and N = N0 [ N1 where M0 and N0 are smooth compact contractible 4-manifolds with boundary ; so that (M1;);and (N1;)are dieomorphic. If M and N are closed; then we may further arrange that M1 and N1 are 1-connected. In fact; if W is an h-cobordism connecting M and N; then W can be written W = W0 [I W1 where (W0;M0;N0)is an (often) nontrivial h-cobordism and (W1;M1;N1)is smoothly the product h-cobordism (M1 I;M1 f0 g;M1 f1 g). This theorem lies in the mainstream of combinatorial 4-manifold theory circa 1975, but, oddly, the result was overlooked. It now ts into a rich context (Donaldson theory) and raises new questions when compared with the known examples. In 1988 Akbulut [A] showed that a manifold X homotopy equivalent to a K3-surface could, after blowing up a point, be transformed into a rational surface Q by cutting out and regluing a certain contractible \Mazur" manifold by an involution of its boundary . At the time a rather delicate argument of Fintushel and Stern (relying on the observed presence of the homology sphere 2;3;7 X) showed that certain Donaldson invariants of X (and its blow up X + ) were nontrivial. This distinguished X + from the h-cobordant manifold Q. In retrospect, this was the rst nontrivial example of our theorem. The result was a surprise: the Donaldson invariant, which derives from the second homology, had been localized on a contractible piece. Recently Bizaca and Gompf [BG] have shown that X is, in fact, dieomorphic to K3, allowing a more direct analysis of its Donaldson invariant. (See e.g. [QK] or [KM].) They also nd an innite family of examples
Hot or not? Impact of seasonally variable soil carbonate formation on paleotemperature and O-isotope records from clumped isotope thermometry

Quantifying the timing and temperature of soil carbonate formation is important for interpreting isotopic records of Earth-surface temperature and soil water composition from paleosols. Pedogenic carbonates typically have been assumed to form at mean annual temperature, but recent work suggests warm-season bias in carbonate formation could impact the interpretation of d 18 O values and carbonate
Copper, zinc superoxide dismutase in Escherichia coli: periplasmic localization.

Abstract Cu,ZnSOD purified from Escherichia coli has been used to raise antibodies in rabbits. The resultant antiserum was found to recognize a single band on Western blots of SDS-polyacrylamide gel electropherograms, and that single band coincided with the position of the Cu,ZnSOD, Ultrathin sections of fixed E. coli were treated with the antibody followed by protein A bearing 10-nm gold particles. Electron microscopy revealed that Cu,ZnSOD was largely localized in the periplasm in polar bays.
Factors Influencing Scholarly Impact: Does Urology Fellowship Training Affect Research Output?

Purpose Residents seek postresidency fellowship training to increase competency with novel surgical techniques and augment their fund of knowledge. Research productivity is a vital component of advancement in academic urology. Our objectives were to use the h-index (an objective and readily available bibliometric that has been repeatedly shown to correlate with scholarly impact, funding procurement, and academic promotion in urology as well as other specialties) to determine whether any relationship exists between fellowship training and scholarly impact among academic urologists. Additional examination was performed to determine whether any differences in scholarly influence are present among practitioners in the major urologic subspecialties. Materials and Methods Overall, 851 faculty members from 101 academic urology departments were organized by academic rank and fellowship completed. Research productivity was calculated using the h-index , calculated from the Scopus database. Results There was no statistical difference in h-index found between fellowship-trained and nonfellowship-trained academic urologists. The highest h-indices were seen among urologic oncologists (18.1 ± 0.95) and nonfellowship-trained urologists (14.62 ± 0.80). Nearly 70% of department chairs included in this analysis were urologic oncologists or general urologists. Conclusions No difference in h-index existed between fellowship-trained and nonfellowship-trained urologists, although practitioners in the subspecialty cohorts with the highest research productivity (nonfellowship-trained and urologic oncologists) comprised 70% of department chairpersons. This relationship suggests that a strong research profile is highly valued during selection for academic promotion. Differences existed on further comparison by subspecialty. Fellowship training may represent another potential opportunity to introduce structured research experiences for trainees.
NITRIC OXIDE REGULATION OF GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE ACTIVITY IN DICTYOSTELIUM DISCOIDEUM CELLS AND LYSATES

The ability of compounds releasing nitric oxide (NO) to regulate glyceraldehyde-3-phosphate dehydrogenase (GraPDH) activity was analysed both in cell homogenates and in intact Dictyostelium discoideum. The time course of GraPDH inactivation in cell lysates by NO-releasing compounds suggests that two processes may be involved, one of which accounts for the majority of the inactivation and shows a close correlation with GraPDH ADP-ribosylation. Maximal ADP-ribosylation under these conditions exhibited a stoichiometry of about 0.4 mol ADP-ribose/mol enzyme tetramer. NO-mediated inhibition of GraPDH activity was attenuated if specific substrates, cofactors, or cysteine were added to cytosol preparations. Under such conditions, ADP-ribosylation of the enzyme was correspondingly reduced or negligible. Intact cells treated with NO-releasing compounds were shown to respond by rapidly decreasing their GraPDH activity. This inhibition was transient and, after a 10-min incubation, enzyme activity returned to the level seen in control cells. The time course of these in vivo changes correlated well with those of the NO-stimulated ADP-ribosylation of GraPDH also seen in intact cells. The basis underlying the NO-stimulated inhibition of GraPDH activity was investigated and found to reflect a decreased Vmax+ No changes in either the Km of the enzyme for its substrates or its state of polymerization were observed.
Structural Shape Prototypes for the Automatic Classification of 3D Objects

This technique for defining and constructing 3D shape prototypes improves automatic 3D content classification and search by summarizing key features of the members of a class, then classifying the query object into the class that the prototype most similar to the given query represents.
Rupture cave sous-rénale isolée secondaire à une contusion minime

Les plaies de la veine cave inferieure (IVC) sont tressouvent mortelles et sont habituellement associes aux plaies par balle. Les contusions de l’IVC sont rares et habituellement situees dans l’espace retro-hepatique. Nous presentons le cas d’une rupture cave sous renale chez un enfant de 9 ans resultant d’une contusion minime. La tomodensitometrie montrait un gros hematome retroperitoneal du a la rupture de l’IVC et un thrombus proximal juste au-dessous des veines renales. Le patient avait une chute de l’hematocrite et une sensibilite abdominale conduisant a l’intervention. Avant la laparotomie, des dispositifs bilateraux d’occlusion par ballon etaient places dans les deux veines femorales. Le patient avait une rupture totale de son IVC juste au-dessus de l’origine des veines iliaques. Les deux-tiers anterieurs de l’IVC etaient avulses, plaquant de ce fait la paroi posterieure contre le retroperitoine. Etant donne l’instabilite hemodynamique et l’importance des lesions veineuses, l’IVC etait liee et une intervention de controle des lesions etait entreprise. Le jour suivant, le patient etait ramene en salle d’operation pour une laparotomie de deuxieme-regard et une fermeture abdominale. Un examen pathologique a indique un sarcome de haut grade a cellules fusiformes. Les contusions de l’IVC sont rares et leur localisation en dehors de l’espace retro-hepatique devrait alerter le chirurgien sur une cause maligne sous-jacente.
CXCR4 acts as a costimulator during thymic beta-selection.

Pre-TCR signaling is essential for the passage of thymocytes through the β-selection checkpoint. Ravichandran and co-workers find that CXCR4 acts as a costimulator for the pre-TCR and is needed for optimal progression through β-selection. Passage through the β-selection developmental checkpoint requires productive rearrangement of segments of the T cell antigen receptor-β gene (Tcrb) and formation of a pre-TCR on the surface of CD4−CD8− thymocytes. How other receptors influence ββ-selection is less well understood. Here we define a new role for the chemokine receptor CXCR4 during T cell development. CXCR4 functionally associated with the pre-TCR and influenced β-selection by regulating the steady-state localization of immature thymocytes in thymic subregions, by facilitating optimal pre-TCR-induced survival signals, and by promoting thymocyte proliferation. We also characterize functionally relevant signaling molecules downstream of CXCR4 and the pre-TCR in thymocytes. Our data designate CXCR4 as a costimulator of the pre-TCR during β-selection.
DETECTION OF CYTOMEGALOVIRUS IN MECONIUM OF INFECTED NEWBORNS BY POLYMERASE CHAIN REACTION. † 1803

Objectives: With the availability of an anti-viral drug therapy, timely diagnosis of congenital cytomegalovirus (CMV) infection is critical in the prevention of significant morbidity. Present diagnostic tests require either long inoculation times or have limited sensitivity. The polymerase chain reaction (PCR) is a highly specific, sensitive and rapid test which has been used for the detection of CMV in urine, blood and amniotic fluid. Meconium which is in constant contact with the amniotic fluid may also be a good source for the detection of CMV. This study was undertaken to determine if CMV could be detected in meconium of newborns with known CMV infection.
Electrical pollution—what is it and how do you prevent it?

This summary paper defines electrical pollution within the context of an electrical power system and draws an analogy between it and air-water pollution. It then describes the principles underlying its prevention. Finally the tools used to predict and design for its mitigation are described. One of these tools, a handheld electrical pollution screening tool, is new and is briefly described.
The effect of food deprivation on intergroup relations in rhesus monkeys.

Behavior between two enclosed social groups of Macaca mulatta was studied during conditions of normal food ration, and under severe food deprivation. Agonistic behavior decreased under deprivation while nonagonistic behavior increased. Overall frequency of intergroup interactions decreased. The results with respect to aggression are comparable to studies of intragroup behavior. The increase in nonagonistic behavior may be a fundamental difference from the intragroup response to food shortage.
Constraints on the two-Higgs doublet model and the tau neutrino magnetic moment from recent LEP data

Abstract Recent data from LEP is used to constrain new physics beyond that predicted by the standard model. We obtain constraints on the anomalous couplings of the tau neutrino to the Z boson and stringent bounds on the parameters of the two-doublet Higgs sector of the minimal SUSY version of the standard model.
Total epidermal cell walls of pea stems respond differently to auxin than does the outer epidermal wall alone

The effect of auxin on cell wall mass in the epidermis of third internodes of Pisum sativum L. cv. Alaska grown in dim red light was investigated using epidermal peels, to determine whether epidermal peels reflect the behavior of the outer epidermal cell wall. In contrast to the outer epidermal wall itself, where auxin caused thinning in proportion to growth (M.S. Bret-Harte et al, 1991, Planta 185, 462–471), auxin promoted an increase in wall mass in epidermal peels from treated internode segments in the absence of exogenously supplied sugar. The percentage gain in mass was smaller than the percentage elongation, however, so mass per unit length decreased in peels from auxin-treated segments. Epidermal peels from auxin-treated segments gained more wall mass than control peels even when adhering internal tissue at the basal end of the peel was removed. Epidermal peels also had a gross composition different from that of the outer wall alone (M.S. Bret-Harte and L.D. Talbott, 1993, Planta 190, 369–378). These discrepancies can be explained by the observation that the outer wall makes up only 30% of the mass of the epidermal peel. It appears that the inner walls of the epidermis, and walls of the outer layer of cortical cells that remain attached to the epidermis during peeling, nearly maintain their thickness by biosynthesis while the outer wall loses mass as previously described (Bret-Harte et al. 1991). These results indicate that epidermal peels may not be a good system for examining the biochemical and physiological properties of the outer epidermal cell wall.
Characterization of a Specificity Factor for an AAA+ ATPase: Assembly of SspB Dimers with ssrA-Tagged Proteins and the ClpX Hexamer

SspB, a specificity factor for the ATP-dependent ClpXP protease, stimulates proteolysis of protein substrates bearing the ssrA degradation tag. The SspB protein is shown here to form a stable homodimer with two independent binding sites for ssrA-tagged proteins or peptides. SspB by itself binds to ClpX and stimulates the ATPase activity of this enzyme. In the presence of ATPγS, a ternary complex of SspB, GFP-ssrA, and the ClpX ATPase was sufficiently stable to isolate by gel-filtration or ion-exchange chromatography. This complex consists of one SspB dimer, two molecules of GFP-ssrA, and one ClpX hexamer. SspB dimers do not commit bound substrates to ClpXP degradation but increase the affinity and cooperativity of binding of ssrA-tagged substrates to ClpX, facilitating enhanced degradation at low substrate concentrations.
Telomeres: Not All Breaks Are Equal

ATM, Rad50 and Mre11 have been shown to prevent telomere fusion in Drosophila, thereby extending the protective role of DNA damage checkpoint proteins to non-canonical telomeres formed without telomerase. How do these proteins help chromosomal termini escape fusion through 'repair' while promoting repair of induced DNA breaks?
Investigation of Phase Transformation in Thin Film Using Finite Element Method

Cahn-Hilliard type of phase field model coupled with elasticity is used to derive governing equations for the stress-mediated diffusion and phase transformation in thin films. To solve the resulting equations, a finite element (FE) model is presented. The partial differential equations governing diffusion and mechanical equilibrium are of different orders; Mixed-order finite elements, with C0 interpolation functions for displacement, and C1 interpolation functions for concentration are implemented. To validate this new numerical solver for such coupled problems, we test our implementation on thin film diffusion couples.
Bionomics and Host Range of the Introduced Basswood Thrips (Thysanoptera: Thripidae)

The introduced basswood thrips, Thrips calcaratus Uzel, feeds on developing buds and often defoliates extensive areas of deciduous forests in the upper midwest. Little is known about the basic biology of this species. Therefore, effects of temperature and host plant on T. calcaratus development were studied. Temperature affected the duration of each life stage, except the 1st instar. Total development time and adult longevity were inversely related to temperature. Total development time ranged from 29.0 d at 15°C to 12.0 d at 30°C. The availability of pollen as a supplemental nutrient source did not enhance attraction or performance of the thrips. T. calcaratus produced the most offspring at 20°C (0.7 eggs per female per day). There is a 2-d preoviposition period before the peak of ovipositional activity. Of the 7 plant genera assayed, 2 could sustain T. calcaratus development to adulthood. Performance on linden and sugar maple was similar, except the egg stage was longer on linden. The implications of T. calcaratus development under these environmental conditions and on these alternate hosts are discussed.
El Salvador: The Military and Politics

Does the conflict in El Salvador, conceptualized by the U.S. government as a battle in the cold war, become more amenable to solution if seen strictly on its own terms? The current struggle seems most intelligible as the latest episode in the post-Conquest struggle of a Spanish-descended elite to maintain control of its land against threat from an Indiandescended peasantry. The military and paramilitary conduct of the struggle has alienated the noninvolved civilian population from the government without drawing them to the guerrilla cause. Since neither side can win militarily under present circumstances, a negotiated settlement may be attainable.
Interference suppression in the presence of quantization errors

Multi-element antennas offer the possibility of increasing the spatial reuse of wireless spectrum by “nulling” out interfering signals. However, the interference suppression performance is highly sensitive to small errors in the gains applied to the antenna elements. In this paper, we examine in detail the effect of one specific source of error that arises from quantizing array weights. We show that a simple approach based on scalar quantization that ignores the correlation of the quantization errors fails to fully utilize the interference suppression capability of the array: the residual interference level does not decrease with the number of antennas. Unfortunately, the optimum approach to computing the weights involves vector quantization over a space that grows exponentially with the number of antennas and number of quantization bits, and is therefore computationally intractable. We propose instead a simple suboptimal method that greedily optimizes the SIR, coefficient-by-coefficient. Simulations show that this greedy approach provides substantial SIR gains over the naive approach, with SIR growing polynomially in the number of antennas. We derive analytical bounds that indicate that even larger SIR gains (exponential in the number of antennas) are potentially achievable, so that finding tractable algorithms that improve upon our suboptimal approach is an important open problem.
Spontaneous left main coronary artery dissection complicated by pseudoaneurysm formation in pregnancy: role of CT coronary angiography

We report a case of a 26-year-old female, who presented at 34 weeks of an uncomplicated pregnancy with an acute ST elevation anterior wall myocardial infarction. Cardiac catheterization suggested a left main coronary artery dissection with pseudoaneurysm formation. The patient's course was complicated by congestive heart failure. She was initially managed conservatively by a multidisciplinary team including heart failure specialists, obstetricians, and cardiovascular surgeons. 4 days after admission, her LMC was imaged by dual-source 64 slice Cardiac computed tomography, coronary dissection was identified extending to the lumen, and the presence of pseudoaneurysm was confirmed. She underwent subsequently a staged procedure, which included placement of an intra-aortic balloon pump, cesarean section, and coronary artery bypass grafting. This case illustrates the utility of coronary artery CT imaging to assess the complexity and stability of coronary artery dissections, thereby helping to determine the need for, and timing of revascularization procedures.
Antagonistic coevolution mediated by phenotypic differences between quantitative traits.

Many well-studied coevolutionary interactions between predators and prey or hosts and parasites are mediated by quantitative traits. In some interactions, such as those between cuckoos and their hosts, interactions are mediated by the degree of phenotype matching among species, and a significant body of theory has been developed to predict the coevolutionary dynamics and outcomes of such interactions. In a large number of other cases, however, interactions are mediated by the extent to which the phenotype of one species exceeds that of the other. For these cases—which are arguably more numerous—few theoretical predictions exist for coevolutionary dynamics and outcomes. Here we develop and analyze mathematical models of interspecific interactions mediated by the extent to which the quantitative trait of one species exceeds that of the other. Our results identify important differences from previously studied models based on trait matching. First, our results show that cyclical dynamics are possible only if the strength of coevolutionary selection exceeds a threshold and stabilizing selection acts on the interacting traits. Second, our results demonstrate that significant levels of genetic polymorphism can be maintained only when cyclical dynamics occur. This result leads to the unexpected prediction that maintenance of genetic polymorphism is enhanced by strong selection. Finally, our results demonstrate that there is no a priori reason to expect the traits of interacting species should match in any literal sense, even in the absence of gene flow among populations.
Dosing patterns for continuous renal replacement therapy in the United States

There is evidence that increasing the dose of continuous renal replacement therapy (CRRT) is associated with improved survival in critically ill patients with acute renal failure (ARF) [1]. In the US, CRRT is usually provided with an ultrafiltrate (UF) and/or dialysis flow rate of 2 l/h irrespective of the patient's weight. Patients undergoing CRRT frequently have their therapy interrupted and hence receive a much lower dose than prescribed. Hence we retrospectively reviewed the records of all patients with ARF, who received CRRT in our hospital in the past year, to determine dosing patterns.
One Hundred Years of Echinacea angustifolia Harvest in the Smoky Hills sof Kansas, USA

Abstract Echinacea angustifolia DC. (Asteraceae) is a major North American medicinal plant that has been harvested commercially in north-central Kansas for 100 years, making it one of the longest documented histories of large-scale commercial use of a native North American medicinal herb. We have compiled historical market data and relate it to harvest pressure on wild Echinacea populations. Interviews with local harvesters describe harvesting methods and demonstrate the species' resilience. Conservation measures for E. angustifolia also should address the other threats faced by the species and may include restoration and management of its mixed-grass prairie habitat and protection by private landowners.
Peskun's theorem and a modified discrete-state Gibbs sampler

Attention is drawn to the use of Peskun's theorem in improving statistical efficiency of discretestate Gibbs sampling.
Mylonitic deformation at the Kane oceanic core complex: Implications for the rheological behavior of oceanic detachment faults

[1] The depth extent, strength, and composition of oceanic detachment faults remain poorly understood because the grade of deformation-related fabrics varies widely among sampled oceanic core complexes (OCCs). We address this issue by analyzing fault rocks collected from the Kane oceanic core complex at 23°30′N on the Mid-Atlantic Ridge. A portion of the sample suite was collected from a younger fault scarp that cuts the detachment surface and exposes the interior of the most prominent dome. The style of deformation was assessed as a function of proximity to the detachment surface, revealing a ∼450 m thick zone of high-temperature mylonitization overprinted by a ∼200 m thick zone of brittle deformation. Geothermometry of deformed gabbros demonstrates that crystal-plastic deformation occurred at temperatures >700°C. Analysis of the morphology of the complex in conjunction with recent thermochronology suggests that deformation initiated at depths of ∼7 km. Thus we suggest the detachment system extended into or below the brittle-plastic transition (BPT). Microstructural evidence suggests that gabbros and peridotites with high-temperature fabrics were dominantly deforming by dislocation-accommodated processes and diffusion creep. Recrystallized grain size piezometry yields differential stresses consistent with those predicted by dry-plagioclase flow laws. The temperature and stress at the BPT determined from laboratory-derived constitutive models agree well with the lowest temperatures and highest stresses estimated from gabbro mylonites. We suggest that the variation in abundance of mylonites among oceanic core complexes can be explained by variation in the depth of the BPT, which depends to a first order on the thermal structure and water content of newly forming oceanic lithosphere.
Wave forces on vertical bodies of revolution

The axisymmetry of a body which is diffracting water waves may be exploited to give a line integral equation to be solved for the scattered wave field and forces on the body. Each term in a previously established surface integral equation is shown to be expressible as a Fourier series, which is then integrated once analytically. The resulting one-dimensional equation is shown to possess singularities, previously ignored by J. L. Black. This equation, with series transformations and subtraction of singularities such that all series are quickly convergent and that it has to be solved only along a curve, reduces computational effort by some three orders of magnitude. Results obtained by this method give good agreement with previous analytical and experimental results, even if a rather coarse numerical approximation is used.
Bone mineral density and the risk of Alzheimer disease

Background Some, but not all, studies have suggested that estrogen replacement therapy has a beneficial effect on cognition in postmenopausal women. Bone mineral density (BMD) is a potential surrogate marker for cumulative estrogen exposure and has been associated with cognitive performance and risk of cognitive deterioration. Objective To examine whether low BMD in elderly individuals is associated with an increased risk of developing Alzheimer disease (AD). Design, Setting, and Participants Community-based prospective cohort study of 987 subjects (610 women) who were cognitively intact and had baseline BMD measured at the femoral neck, the trochanter, and the radial shaft between 1988 and 1989. Main Outcome Measures Incidence of AD and all-cause dementia during an 8-year follow-up period. Results Women in the lowest quartile of femoral neck BMD had more than twice the incidence of AD (hazard ratio, 2.04; 95% confidence interval, 1.11-3.75) and all-cause dementia (hazard ratio, 2.01; 95% confidence interval, 1.16-3.49) compared with those in higher quartiles after adjusting for age, sex, apolipoprotein E e4, baseline homocysteine level, education, estrogen use, smoking, and stroke. A similar but statistically nonsignificant relationship was observed between BMD of the femoral trochanter and AD, while no such relationship was seen between radial BMD and AD or all-cause dementia. In men, there was a trend toward an inverse relationship between BMD and the risk of AD, but the relationship was not statistically significant at any of the 3 sites. Conclusions Low femoral neck BMD was associated with approximately 2 times the risk of AD and all-cause dementia in women but not men, suggesting the possibility that cumulative estrogen exposure may influence the risk of developing AD. Additional studies are needed to confirm this correlation.
A Life of Quality: Informing the UN Convention on the Rights of Persons With Disabilities:

Quality of life is a multidimensional construct requiring self-determination and advocacy skills, employment, and recognition of basic human rights and fundamental freedoms for improvements to be made. In this study, the constructs of quality of life and self-determination were applied to the rights-based framework guaranteed by the recent United Nations Convention on the Rights of Persons With Disabilities (UNCRPD) to inform monitoring and implementation efforts. Persons with disabilities interested in advocacy from Nepal, Zambia, and the United States were surveyed. Significant country differences were found in ratings of quality of life, self-determination, and personal human rights, but similar low ratings in country support of human rights were found. Through the coordinated improvement of significant factors, this study supports quality of life as a useful measure for informing UNCRPD. Future research should focus on the applicability of quality of life to monitoring UNCRPD and policy and program de...
Passivity properties of low-sensitivity digital filter structures

A general representation of a class of low passband sensitivity digital filter structures is proposed. The proposed representation for a transfer function of order N consists of an (N + 1) -pair memoryless system terminated at N -pairs by delays. The (N + 1) -pair system contains only adders and multipliers, and is described by an orthogonal transfer matrix. The set of terminating delays can be looked upon as an N -pair system with transfer matrix z^{-1}{\bf 1} . Certain wave digital filter structures, Gray-Markel lattice structures and the coupled-form biquadratic section belong to the general form advanced here. Several properties satisfied in these special cases are derived in a unified manner using the generalized representation. Also, a quantization scheme that makes the structure free from zero-input limit cycles even under time-varying conditions is advanced, unifying similar such results independently reported for the above well-known structures.
Applying the symmetry properties of third order cumulants in the identification of non-Gaussian ARMA models

The third order cumulant of the output of an ARMA (p,q) model, driven by unobservable non-Gaussian i.i.d. noise, is used to identify the model parameters. The model is assumed to be causal and stable but need not be minimum-phase. The symmetry properties of the third order cumulant are applied to use the cumulant values in the first non-redundant region, where it is proved that the matrices used to solve for the AR parameters are of full rank and have a transpose equivalence that can be used to enhance the efficiency of the estimation process. The estimated AR parameters are then used to estimate the MA order and parameters. The simulation results also show that the AR model order can be estimated from the scattering of the estimated poles in the complex Z-plane. >
Reverse Genetic Characterization of Cytosolic Acetyl-CoA Generation by ATP-Citrate Lyase in Arabidopsis

Acetyl-CoA provides organisms with the chemical flexibility to biosynthesize a plethora of natural products that constitute much of the structural and functional diversity in nature. Recent studies have characterized a novel ATP-citrate lyase (ACL) in the cytosol of Arabidopsis thaliana. In this study, we report the use of antisense RNA technology to generate a series of Arabidopsis lines with a range of ACL activity. Plants with even moderately reduced ACL activity have a complex, bonsai phenotype, with miniaturized organs, smaller cells, aberrant plastid morphology, reduced cuticular wax deposition, and hyperaccumulation of starch, anthocyanin, and stress-related mRNAs in vegetative tissue. The degree of this phenotype correlates with the level of reduction in ACL activity. These data indicate that ACL is required for normal growth and development and that no other source of acetyl-CoA can compensate for ACL-derived acetyl-CoA. Exogenous malonate, which feeds into the carboxylation pathway of acetyl-CoA metabolism, chemically complements the morphological and chemical alterations associated with reduced ACL expression, indicating that the observed metabolic alterations are related to the carboxylation pathway of cytosolic acetyl-CoA metabolism. The observations that limiting the expression of the cytosolic enzyme ACL reduces the accumulation of cytosolic acetyl-CoA-derived metabolites and that these deficiencies can be alleviated by exogenous malonate indicate that ACL is a nonredundant source of cytosolic acetyl-CoA.
Multicomponent mass transfer I. Theory

As the primary phase in the development of multicomponent mass transfer theory, equations are derived which predict the rate of mass transfer of each species from an interface to a ternary gas mixture in turbulent flow for equimolal-countercurrent transfer and for transfer with one of the three gases stagnant. The mass transfer equations obtained, regardless of whether a film, Prandtl-Taylor, or modified Chilton-Colburn model is used, differ in form from the usual binary equations and predict qualitative as well as large quantitative differences between binary and ternary transfer. A criterion is obtained which any consistent multicomponent mass transfer theory must satisfy, and although the ternary film and Prandtl-Taylor models satisfy this criterion, the modified ternary Chilton-Colburn model does not.
Opportunity makes the thief. Really? And so what?

This paper describes the work undertaken over many years by the author and colleagues concerning the role of opportunity in crime. The work began in the early 1970s in the Home Office Research Unit, the British government’s criminological research department. The work supported a preventive approach – situational crime prevention – that was highly contentious in the criminology of the day because it sought to reduce opportunities for crime, rather than to modify offender propensities. Critics claimed that situational crime prevention would displace rather than reduce crime because they assumed that opportunity merely determines the time and place of crime, but does not cause it. This paper describes the difficulties in establishing that opportunity is cause of crime and why this took so long. It reviews the research that was undertaken to this end, and it summarizes the benefits for criminology and crime policy of accepting that opportunity does cause crime.