cssi/SciSciGPT-SciSciNet huggingface dataset:
Nicotine dependence and psychiatric and substance use disorder comorbidities among American Indians/Alaska Natives: Findings from the National Epidemiologic Survey on Alcohol and Related Conditions

Abstract Background American Indians and Alaska Natives (AI/ANs) have high rates of tobacco use compared to the general population. AI/ANs also have elevated rates of psychiatric and substance use disorders associated with nicotine dependence. However, very few studies have examined the comorbidity between nicotine dependence and psychiatric and substance use disorders within this population. Methods This study analyzes the comorbidity of lifetime nicotine dependence with both current and lifetime psychiatric disorders and substance use disorders in a nationally representative sample of 701 AI/AN women and men. Results Using 95% confidence interval testing, lifetime nicotine dependence (29.5%) was associated with all main diagnostic categories (any mood disorder, any anxiety disorder, any personality disorder, any alcohol use disorder, and any drug use disorder) both at the lifetime level and current (12-month) level. Of the lifetime disorders, the strongest associations were with psychosis and drug dependence. For (current) 12-month disorders, the strongest associations were with alcohol dependence and drug dependence. Differences were noted between genders regarding personality disorders. Conclusions Culturally appropriate tobacco screening, prevention, and treatment curricula for adult AI/ANs with dual diagnoses are recommended. Understanding historically based factors that may contribute to psychiatric illness and substance use disorders may assist in more effective nicotine treatments for AI/ANs.
The ionosphere of Uranus: A myriad of possibilities

A one-dimensional model has been used to study the effects of exospheric temperature, methane and water influx, ionospheric outflow, and electron precipitation on the composition and structure of the ionosphere of Uranus. Peak ion concentrations range from 1000 to 1 million per cu cm with a wide variation in peak altitude, which depends strongly on the exospheric temperature. In all the cases considered, H(+) is the major ion in the topside ionosphere. At altitudes near or below the peak, H3(+) and CH5(+) can dominate, depending on the magnitude of CH4 and H2O influx. Atomic hydrogen column depths above the methane absorbing layer exceed 10 to the 17th per sq cm and can produce large (400 R) emissions of resonantly scattered Lyman-alpha. In the sunlit polar cap, electron precipitation with energy fluxes of 0.6 to 1.0 erg/sq cm s results in direct production of Lyman-alpha emissions that exceed 1 kR.
Anatomical correlates of electrical and behavioral events related to amygdaloid kindling

Anatomical structures demonstrating increased glucose uptake during the various stages of amygdaloid kindling in rats were identified by the 14C-2-deoxyglucose (DG) autoradiographic technique. Partial (stages 1 and 2) seizures were correlated with increased DG uptake in the ipsilateral amygdala and its direct projection fields. The appearance of generalized motor (stages 3,4, and 5) seizures was accompanied by less limbic involvement and recruitment of a bilateral system including substantia nigra, specific and nonspecific thalamic nuclei, globus pallidus, and neocortex. Increased hippocampal DG uptake was correlated with prolonged amygdaloid after discharge duration but not with the behavioral seizure stage. This study does not reveal which of these structures are responsible for the observed behavioral and electrical events and which are activated by them. It does suggest, however, that three discrete anatomical systems underlie the generation of partial seizures, generalized motor seizures, and local after discharge.
Maximal orthogonality and pseudo-orthogonality with applications to generalized inverses

Equip a finite-dimensional vector space V over a field F with a nondegenerate symmetric bilinear, alternating bilinear, or hermitian form. Fix some subspace U of V. The concept of a maximally orthogonalcomplementary subspace for U is presented and shown to be related to the concept of a pseudo-orthogonal complementary subspace from an earlier paper. When F =G F(q), the number of maximally orthogonal (pseudo-orthogonal) complements is computed. Also, both types of complements are characterized as orthogonal complements with respect to related forms. This is used to relate certain reflexive generalized inverses of linear transformations to Moore‐Penrose inverses. Techniques are presented for deriving the related forms, which, together with standard techniques for computing Moore‐Penrose inverses, can be used to compute the desired generalized inverses. Lastly, vectors of V that occur in such complementary subspaces of U are characterized. © 2000 Elsevier Science Inc. All rights reserved.
Covariance Models For Latent Structure In Longitudinal Data

We present several approaches to modeling latent structure in longitudinal studies when the covariance itself is the primary focus of the analysis. This is a departure from much of the work on longitudinal data analysis, in which attention is focused solely on the cross-sectional mean and the influence of covariates on the mean. Such analyses are particularly important in policy-related studies, in which the heterogeneity of the population is of interest. We describe several traditional approaches to this modeling and introduce a flexible, parsimonious class of covariance models appropriate to such analyses. This class, while rooted in the tradition of mixed effects and random coefficient models, merges several disparate modeling philosophies into what we view as a hybrid approach to longitudinal data modeling. We discuss the implications of this approach and its alternatives especially on model interpretation. We compare several implementations of this class to more commonly employed mixed effects models to describe the strengths and limitations of each. These alternatives are compared in an application to long-term trends in wage inequality for young workers. The findings provide additional guidance for the model formulation process in both statistical and substantive senses.
Corneal epithelial adhesion strength to tethered-protein/peptide modified hydrogel surfaces.

In this study, we investigated the suitability of microjet impingement for use on hydrogel materials to determine the cellular adhesion strength of corneal epithelial cells grown on novel hydrogels with extracellular matrix proteins (laminin and/or fibronectin) or a peptide sequence (fibronectin adhesion promoting peptide, FAP) tethered to their surface with poly(ethylene glycol) chains. The deformation of the hydrogel surface in response to the force of the microjet was analyzed both visually and mathematically. After the results of these experiments and calculations determined that no deformation occurred and that the pressure required for indentation (1.25 × 106 Pa) was three factors of 10 greater than the maximum pressure of the microjet, the relative mean adhesion strength of primary rabbit corneal epithelial cells grown on the novel poly(2-hydroxyethyl methacrylate-co-methacrylic acid) hydrogels was determined and compared with that of the same type of cells grown on control glass surfaces. Only confluent cell layers were tested. Cells grown on control glass surfaces adhered with a mean relative adhesion strength of 488 ± 28 dynes/cm2. Under identical conditions, cells grown on laminin- and FAP-tethered hydrogel surfaces were unable to be removed, indicating an adhesion strength greater than 516 dynes/cm2. Cells grown on fibronectin- and fibronectin/laminin (1:1)-tethered surfaces showed significantly lower relative adhesion strengths (201 ± 50 and 189 ± 11 dynes/cm2, respectively), compared with laminin- and FAP-tethered surfaces (p = 0.001). Our results demonstrate that the microjet impingement method of cell adhesion analysis is applicable to hydrogel substrates. Additionally, analysis of our test surfaces indicates that fibronectin tethered to this hydrogel in the quantity and by the method used here does not induce stable ligand/receptor bonding to the epithelial cell membrane to the same degree as does laminin or FAP. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 72A: 19–24, 2005
Deep water formation and exchange rates in the Greenland/Norwegian Seas and the Eurasian Basin of the Arctic Ocean derived from tracer balances

Abstract Multi-tracer data sets collected in the Greenland/Norwegian seas and the Eurasian Basin of the Arctic Ocean in the 1970s and 1980s are used, together with temperature and salinity, to (1) constrain box model calculations of the deep water formation rates in the Greenland Sea and the Eurasian Basin of the Arctic Ocean, and (2) estimate the exchange rates of deep waters (depth ≥1,500m) between the Greenland/Norwegian Seas and the Eurasian Basin. We obtain deep water formation rates of 0.1Sv (since 1980) to 0.47Sv (from at least 1965 to 1980) for the Greenland Sea, and 0.3Sv for the Eurasian Basin of the Arctic Ocean. The southward flux of Eurasian Basin Deep Water through Fram Strait is estimated to be about 1Sv. About 0.12Sv of this flux are transported into the Greenland Sea, about 0.37Sv reach the deep Norwegian Sea through the Jan Mayen Fracture Zone, and about 0.39Sv leave the Arctic Ocean through a shallower core which more or less directly feeds into the Iceland Sea, and, after modification, eventually ends up in the overflow waters. The outflow of Eurasian Basin Deep Water is balanced by deep water formation in the Arctic Ocean and by inflow of Norwegian Sea Deep water. About 0.77Sv of deep water formed in the Greenland Sea and the Eurasian Basin contribute to the formation of North Atlantic Deep Water. Uncertainties of the fluxes are estimated to be roughly ±20 to 30%.
A question of Hille on inversion of differential operators of infinite order

Abstract The inversion problem for differential equations of the form G(Dz) = F(z) is studied. Here Dz is a linear differential operator of order n having entire coefficients with the leading coefficient a polynomial whose zeros are suitably restricted. The function G is entire of order at most 1 n , minimal type, and the function F is analytic in a neighborhood of an interval on the real axis. Conditions for obtaining an analytic solution W of the above equation are given.
Constructivist therapy with serious disturbances

Abstract There have been few systematic applications of constructivist principles to the therapy of severe disturbances, despite an increased interest in constructivist therapies (e.g., Neimeyer & Mahoney, 1995) and data suggest that psychotherapy with seriously disturbed persons is cost effective (Karon, 1992). We address this neglect in two ways. First we describe four important principles of constructivist therapy (the credulous approach, the invitational mode, transitive diagnosis, and optimal therapeutic distance) and illustrate the implications of these principles in the therapy of severely disturbed persons. Next, we discuss constructivist understandings of hallucinations, delusions, and destructive acting out, symptoms seen in severe disturbances that are anxiety arousing for therapists. Finally, the therapeutic implications of these constructivist conceptualizations are discussed.
Kinetics of phase layer growth during aluminide coating of nickel

The diffusion coating of nickel with aluminum was studied by a two-step aluminizing pack process involving initially an influx of aluminum at the surface (step 1) and later a partial honiogenization of the aluminum-rich region under conditions of zero surface flux (step 2). The process was studied in the temperature range from 870 to 1000°C. Step 1 was characterized mainly as the rapid, parabolic growth (after an initial transient period) of the Ni2Al3 phase (γ) as a surface layer with concurrent growth of a thinner NiAl (δ) layer. Step 2 was characterized mainly as the rapid loss of the aluminum gradient in the γ layer followed by parabolic growth of the δ layer primarily by the solution of they phase. Mathematical models were developed, in which numerical methods and computer techniques as well as closed-form solutions were utilized. The models yielded growth rate predictions in agreement with the experimental data and were used to define the critical parameters controlling growth kinetics for the aluminide layers formed during this process.
Use of an Endogenous Plasmid Locus for Stable in trans Complementation in Borrelia burgdorferi

ABSTRACT Targeted mutagenesis and complementation are important tools for studying genes of unknown function in the Lyme disease spirochete Borrelia burgdorferi. A standard method of complementation is reintroduction of a wild-type copy of the targeted gene on a shuttle vector. However, shuttle vectors are present at higher copy numbers than B. burgdorferi plasmids and are potentially unstable in the absence of selection, thereby complicating analyses in the mouse-tick infectious cycle. B. burgdorferi has over 20 plasmids, with some, such as linear plasmid 25 (lp25), carrying genes required by the spirochete in vivo but relatively unstable during in vitro cultivation. We propose that complementation on an endogenous plasmid such as lp25 would overcome the copy number and in vivo stability issues of shuttle vectors. In addition, insertion of a selectable marker on lp25 could ensure its stable maintenance by spirochetes in culture. Here, we describe the construction of a multipurpose allelic-exchange vector containing a multiple-cloning site and either of two selectable markers. This suicide vector directs insertion of the complementing gene into the bbe02 locus, a site on lp25 that was previously shown to be nonessential during both in vitro and in vivo growth. We demonstrate the functional utility of this strategy by restoring infectivity to an ospC mutant through complementation at this site on lp25 and stable maintenance of the ospC gene throughout mouse infection. We conclude that this represents a convenient and widely applicable method for stable gene complementation in B. burgdorferi.
A lower bound on the number of iterations of long-step primal-dual linear programming algorithms

Recently, Todd has analyzed in detail the primal-dual affine-scaling method for linear programming, which is close to what is implemented in practice, and proved that it may take at leastn1/3 iterations to improve the initial duality gap by a constant factor. He also showed that this lower bound holds for some polynomial variants of primal-dual interior-point methods, which restrict all iterates to certain neighborhoods of the central path. In this paper, we further extend his result to long-step primal-dual variants that restrict the iterates to a wider neighborhood. This neigh-borhood seems the least restrictive one to guarantee polynomiality for primal-dual path-following methods, and the variants are also even closer to what is implemented in practice.
Catechol-O-Methyltransferase Valine158Methionine Genotype and Resting Regional Cerebral Blood Flow in Medication-Free Patients with Schizophrenia

Background A valine 158 methionine (val 158 met) polymorphism in catechol- O -methyltransferase ( COMT ) modulates cortical dopaminergic catabolism and has been associated with schizophrenia. Consistent with schizophrenia itself, during cognitive tasks, the risk ( val ) allele predicts less efficient prefrontal cortex (PFC) physiology and worse performance, while during aversive stimuli viewing, this allele predicts less limbic activation. Task-independent effects of this polymorphism in schizophrenia have not yet been characterized. Methods Twenty-five medication-free patients (28 ± 6 years; 19 male patients) and 47 healthy individuals (29 ± 8 years; 33 male individuals) were genotyped for the COMT val 158 met polymorphism and underwent two 60-second radiolabeled water ([ 15 O]H 2 O) regional cerebral blood flow (rCBF) positron emission tomography scans (10 mCi/scan) during rest. Data were analyzed with a random-effects general linear model using COMT genotype as a covariate. Results In patients, but not healthy individuals, val (risk) allele load predicted less regional cerebral blood flow in the right dorsolateral PFC, right superior temporal gyrus, and left precuneus, but greater rCBF in the amygdala and parahippocampal gyrus. Conclusions In schizophrenia, brain structures important for executive and affective processing show activity that is differentially predicted by COMT allelic variation in an opposing manner even at rest, providing evidence for the salience of prefrontal dopaminergic tone in task-independent, basal-level neural activity.
Persistent Atmospheric and Oceanic Anomalies in the North Atlantic from Summer 2009 to Summer 2010

AbstractIn this work, the authors analyze the air–sea interaction processes associated with the persistent atmospheric and oceanic anomalies in the North Atlantic Ocean during summer 2009–summer 2010 with a record-breaking positive sea surface temperature anomaly (SSTA) in the hurricane Main Development Region (MDR) in the spring and summer of 2010. Contributions to the anomalies from the El Nino–Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO), and a long-term trend are identified. The warming in the tropical North Atlantic during summer 2009–summer 2010 represented a typical response to ENSO, preconditioned and amplified by the influence of a strong and persistent negative phase of the NAO. The long-term trends enhanced the warming in the high and low latitudes and weakened the cooling in the midlatitudes. The persistent negative phase of the NAO was associated with active thermodynamic air–sea interaction in the North Atlantic basin. Surface wind anomalies associated with the NAO alter...
Characterization of transcranial ultrasonic passage in the Göttingen minipig

There is continuing interest in targeted transcranial stimulation of deep brain structures using techniques such as low intensity focused ultrasound (LIFU). Accurate transcranial targeting and dosage of acoustic energy onto target neural structure requires quantification of the acoustic effect the skull has on the ultrasound wave. The objective of this work is to assess the effect of transcranial passage, both in terms of attenuation and orientation of an incident acoustic wave, in the gyrencephalic Gottingen minipig. Precision measurements of the acoustic transit of the stereotactically addressed intact-skulls resulted in a consistently measured acoustic loss of about 8.5 dB from the skull transition, corresponding to an intensity transmission coefficient of 0.1298 ± 0.00990. Negligible spatial shift in the acoustic focus was observed. These results indicate that the Gottingen minipig may be suitable for studies of targeted transcranial neuromodulation due to the predictable acoustic transmission measured from the intact skull.
Immunocytochemical localization of angiotensin II immunoreactivity and demonstration of angiotensin II binding in the rat ovary.

The cellular localization of angiotensin II immunoreactivity and the presence of angiotensin II binding in rat ovaries were studied. Angiotensin II immunohistochemical staining was demonstrated throughout the corpora lutea of gonadotropin-stimulated immature rats and pseudopregnant adult rats, as well as in some stromal and thecal cells surrounding large antral follicles. No immunostaining was observed in granulosa cells of preantral or antral rat follicles or in ovaries from unstimulated immature rats. With in vitro auto radiography, specific, saralasin-suppressible 125 I-angiotensin II binding was demonstrated in normal cycling rat ovaries: diestrus > proestrus > estrus. The combined findings of angiotensin II immunostaining in ovarian follicles and corpora lutea and of cycle-related angiotensin II binding support the hypothesis of a functional role for the ovarian renin-angiotensin system.
Starvation-survival of deep subsurface isolates

Six deep, subsurface endolithic isolates were subjected to starvation conditions for up to 100 days in artificial pore water, formulated to mimic in situ geochemical conditions in the nearly saturated rock. Most isolates demonstrated the typical starvation-survival curve for chemoheterotrophic bacteria, and all became miniaturized during starvation. Starvation indices were developed to compare changes in viable cell counts between isolates. Two isolates retained higher viability after 100 days of starvation-survival. High survival correlated with sustained respiration, measured by iodonitrotetrazolium-formazan production, during starvation. In all but one case, isolates plated on two nutritionally dilute media, metal-containing and antibioticcontaining media, showed similar viable counts.
A developmental-psychodynamic model for diabetic control

This paper elaborates a psychodynamic-developmental model as a framework for understanding the wide range of adaptive and maladaptive responses to the self-care requirements of diabetes. Early life experience participates with other factors in influencing the ease with which diabetics implement diabetic control. This model emphasizes the importance of the mother-child interaction during the second phase of development, the toddler phase, at which time the child begins to establish a sense of autonomy and control over his own body and its functions, with bowel training viewed as a paradigm for body control. It is postulated that certain types of mothers such as controlling-intrusive mothers, overprotective mothers, or guilty, indifferent, or rejecting mothers create problems for the child related to the development of autonomy and the sense of comfortable and pleasurable control over his bodily functions. Conflicts generated during this period are reactivated with the onset of diabetes and lead to difficulty in implementing control. In some situations where conflicts with the caretaker figure were predominantly limited to aspects of control, trusting relations acted as a substrate for change and improvement in control in a supportive medical environment. Specific management recommendations based upon this model are presented.
Conceptual Schemes Revisited: Davidsonian Metaphysical Pluralism

Davidson’s 1974 argument denying the possibility of incommensurable conceptual schemes is widely interpreted as entailing a denial of metaphysical pluralism. Speakers may group objects differently or have different beliefs about the world, but there is just one world. I argue there is tension arising from three aspects of Davidson’s philosophy: (1) the 1974 argument against conceptual schemes; (2) Davidson’s more recent emphasis on primitive triangulation as a necessary condition for thought and language; and (3) Davidson’s semantic approach to metaphysics, what he calls ‘the method of truth in metaphysics’. After elucidating the tension, I argue the tension can be resolved while preserving at least two major tenets of Davidson’s philosophy: (1) conceptual schemes do not carve an uninterpreted reality into different worlds and (2) truth is objective and non-epistemic. I argue Davidson is implicitly committed to a plurality of worlds.
An axiom system for database transactions

Abstract A class of transactions is defined that expresses exactly first-order definable database updates. A complete Hoare axiom system is developed for the reasoning of transactions. The system has applications in the verification, optimization, and synthesis of database programs.
Simulation of ultrashort electron pulse generation from optical injection into wake-field plasma waves

A laser-plasma-based source of relativistic electrons is described in detail, and analyzed in two dimensions using theoretical and numeric techniques. Two laser beams are focused in a plasma, one exciting a wake-field electron plasma wave while another locally alters some electron trajectories in such a way that they can be trapped and accelerated by the wave. Previous analyses dealt only with one-dimensional models. In this paper two-dimensional particle-in-cell simulations and analysis of single particle trajectories show that the radial wake field plays an important role. The simulation results are interpreted to evaluate the accelerated electron beam's properties and compared with existing devices.
THE TAXONOMIC IMPLICATIONS OF POLLEN MORPHOLOGY IN SOME SOUTH AMERICAN SPECIES OF MIMULUS (SCROPHULARIACEAE)

The pollen grains of South American hexaploid representatives of the Mimulus glabratus complex, section Simiolus, and M. bridgesii, a South American species sometimes included in this complex and sometimes in section Paradanthus, were examined by light and scanning electron microscopy. Mimulus bridgesii has (6-) 4-5-zoniaperturate grains nearly identical to those observed in a complex of species in section Paradanthus. South American members of the M. glabratus complex (M. bridgesii excluded) have the irregularly synaperturate, + spiraperturate pollen typical of section Simiolus (sensu Grant). Treatment of M. bridgesii as a palynologically aberrant member of section Simiolus is not supported by what is known about the evolution of pollen types in Mimulus and the evolution and dispersal of the M. glabratus complex. DISAGREEMENT PERSISTS regarding the natural affinities of the South American species Mimulus bridgesii (Benth.) Clos. Historically, it has been allied with A. glabratus var. parviflorus (Lindl.) Grant (M. parviflorus Lindl.) of section Simiolus (Lindley, 1825; Bentham,
Stroke-in-evolution an indication for an emergency extracranial-intracranial bypass

Abstract The role of the emergency extracranial-intracranial by-pass in the management of the stroke-in-evolution is controversial. A case is presented in which the patient's fluctuating clinical picture was influenced by hemodynamic factors. The site of occlusion was inaccessible and an emergency extracranial-intracranial bypass was made to restore cerebral blood flow. The patient made a dramatic recovery after the operation. An emergency extracranial-intracranial bypass may be indicated in carefully selected cases.
The automatic initialization of an object-oriented knowledge base

This paper describes mechanisms for automatically building an initial set of knowledge base objects by processing natural language text in a restricted domain. A separate component assigns syntactic and domain-specific semantic tags to each of the words in the text. The syntactic and semantic tags are used to generate names of objects to be added to specific semantic classes in the knowledge base. An algorithm to ensure that the knowledge base objects created are not redundant is specified. The definition and organization of metaknowledge structures is also discussed. To ensure that the name generation and knowledge management techniques are domain-independent, any domain-specific information is isolated in a knowledge base definition file.
Safety and protection when using ionising radiation

Dental care professionals and their patients need to be protected from the harmful effects of ionising radiation. By interpreting and applying the laws and regulations that govern radiation, staff can minimise exposure and therefore risk
Effects of an Insecticide and Potential Predators on Green Frogs and Northern Cricket Frogs

Worldwide amphibian population declines have occurred in the last few decades and have been attributed to a range of factors including introduced species and chemical contamination. Anuran species may differ in their susceptibility to declines based on life-history characteristics, leading to different probabilities of decline and conservation statuses. In this experiment, we looked at two anuran species, Northern Cricket Frogs (Acris crepitans) and Green Frogs (Rana clamitans), reared in mesocosms containing a common invasive or introduced potential predator (Rusty Crayfish, Bluegill Sunfish, or triploid Grass Carp) and imidacloprid, a common insecticide. We found that anurans differed in their sensitivity to these factors. Cricket Frog survival was significantly reduced with imidacloprid exposure, whereas Green Frogs were not. Abundance of both amphibian species was reduced in the presence of predators, particularly the fish. Our study suggests that Cricket Frogs may be especially sensitive to the insecticide imidacloprid, as well as fish predators, and that these factors could contribute to their population declines.
Tetrahedral meshes from planar cross-sections

In biomedicine, many three-dimensional (3D) objects are sampled in terms of slices such as computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound imaging. It is often necessary to construct surface meshes from the cross sections for visualization, and thereafter construct tetrahedra for the solid bounded by the surface meshes for the purpose of finite element analysis. In Ref. [1] (C. Bajaj, E. Coyle and K. Lin, Graphical Models and Image Processing 58 (6) (1996) 524–543), we provided a solution to the construction of a surface triangular mesh from planar -section contours. Here we provide an approach to tetrahedralize the solid region bounded by planar contours and the surface mesh. It is a difficult task because the solid can be of high genus (several through holes) as well as have complicated branching regions. We develop an algorithm to effectively reduce the solid into prismatoids, and provide an approach to tetrahedralize the prismatoids. Our tetrahedralization approach is similar to the advancing front technique (AFT) for its flexible control of mesh quality. The main criticism of AFT is that the remaining interior may be badly shaped or even untetrahedralizable. The emphasis of our prismatoid tetrahedralization approach is on the characterization and prevention of untetrahedralizable parts. Ruppert and Seidel (J. Ruppert, R. Seidel, On the difficulty of tetrahedralizing three-dimensional non-convex polyhedra, in: Proceedings 5th Annual ACM Symposium Comput. Geom., 1989, p. 380–392) have shown that the problem of deciding whether a polyhedron is tetrahedralizable without adding Steiner points is NP-complete. We characterize this problem under certain constraints, and design one rule to reduce the chance of generating untetrahedralizable shapes. The characterization also leads to the classification of two common untetrahedralizable categories which can be better processed if they do occur.
Discourse aspects of tense marking in Belizean Creole

Debates on the relationship between the aspectual properties of verbs and past marking in Caribbean English Creoles tend to focus on two main issues. The first is the semantic function of the “relative past” and its relation to the unmarked verb, and the second is the discourse functions of the relative past marker and the unmarked verb. This paper addresses two issues related to this debate. Using fieldwork data from Belizean Creole, I present a qualitative analysis of tense usage in discourse focusing on the role of the inherent lexical aspect (aktionsart) of predicates. I examine how two different notions of past meaning are distributed between marked and unmarked verbs with different aktionsarten. I also look at the discourse function of these verbs in the contexts of the meanings expressed. I argue that an analysis of both the aktionsarten of the verbs and discourse factors are critical to developing an understanding of the range of meanings and functions of both the relative past marker and the unmarked verb. The paper also presents a new approach to the study of temporal reference in creoles. The picture-based story method provides an objective way of evaluating speakers’ choice of grounding and also facilitates comparison across speakers, given that several potentially variable aspects of the narrative are controlled for.
An InAlAs/InGaAs heterojunction bipolar transistor clocked latch on InP

A clocked latch functioning as a simple comparator with InAlAs/InGaAs heterojunction bipolar transistors (HBTs) on an InP substrate is discussed. Typical comparator offset voltages of 2 mV, and as low as 0.2 mV, along with differential pair measurements indicate good V/sub be/ matching of the HBTs in the circuit. A thermal hysteresis of approximately 1 mV was measured. These results are comparable to those for the best GaAs HBT-based comparators, despite the unoptimized device fabrication procedure. Additionally, these comparators are able to operate at low power levels and with a 2-V input common-mode voltage range. Despite remaining materials problems, these results indicate that InP-based HBTs have great potential for high-speed, low-power digital and linear small- and medium-scale ICs due to the ease of good ohmic contact formation, the low base-emitter diode turn-on voltage, and the intrinsically high speed and scalability of InP-based HBTs. >
The Effects of Partial-Body Irradiation on Delayed Responses

A series of studies involving the partial-body and partial-brain irradiation of rats and monkeys has yielded the following information concerning delayed effects. Rats receiving 650 rads to the lower body showed a transient weight loss followed by a return to normal growth pattern, whereas animals receiving 1300 rads upper-body exposure exhibited a similar early weight loss, and in addition a permanent impairment of growth. Exposures of 650 rads upper body or 1300 rads lower body resulted in no acute deaths in rats, but did cause an equal and significant lifetime shontening. The above exposures resulted in a hastening of the appearance of tumors in the irradiated animals as compared to the unirradiated controls. Rats or monkeys receiving x-ray doses in the 2000 to 4000-rad range to the spinal cord developed, after a period of five to nine months, a lesion of the spinal cord characterized by hind-limb paralysis and loss of sphincter control of bladder and rectum. The clinical signs could be related to a demyelinating lesion affecting the ventral and lateral columns of white matter, proceeding to malacia and liquefaction. Monkeys receiving 3500-rad x-ray exposures to a limited portion of the brain began to show EEG changes after sixmore » to eight weeks, followed by clinical changes at three months. Finally, pathology of the irradiated brain was characterized by necrobiotic lesions and gross swelling of the cortical or subcortical structures, circumscribed and confluent areas of demyelination, zones of reactive astrocytic response and a variety of vascular changes.« less
Efficient preparation of aminoacylated dinucleoside phosphates with N-FMOC amino acid fluorides

Abstract A procedure for the efficient aminoacylation of oligonucleotides has been developed. Internucleoside phosphates are protected with the β-cyanoethyl group prior to aminoacylation with N-FMOC amino acid fluorides. Deprotection with oximate removes all protecting groups without disturbing the aminoacyl linkage.
Biological physics in four lectures and three applications

Abstract An introduction to Biological Physics is provided by three applications of Statistical Mechanics to current problems of biological interest. They are the possibility of lateral phase separation in the plasma membrane, the design of a vesicle sensitive to its environment which could be used for drug delivery, and the process of fusion of biological membranes.
The Past is Tomorrow. Towards an Archaeology of the Vanishing Present

This paper arises from a dissatisfaction with the ‘Great Divides’ created between past and present, self and others, people and material culture in the context of ethnoarchaeology. While conducting ethnoarchaeological research in Spain, Ethiopia and Brazil, I have been faced with the theoretical and practical shortcomings of this field, which is too deeply rooted in modernist concerns and prejudices. I propose a reconsideration of ethnoarchaeology as archaeology tout court – an archaeology of the present – which has to be symmetrical in character. This means that present and past must not be hierarchically conceived – the former in the service of the latter or vice versa – nor strictly separated ontologically, and the relations between humans and things have to be properly problematized.
Castles, Battles, and Bombs: How Economics Explains Military History

Jurgen Brauer and Hubert Van Tuyll (2007). Published by University of Chicago Press, Chicago. Economic methods are increasingly being exploited to analyze national security issues. Indeed, since 9/...
Nutritional correlates of frequency and length of breastfeeds in rural Bangladesh

Abstract In this rural Bangladeshi sample of 165 mothers and their breastfed infants aged 5–23 months, mean maternal body mass index (BMI) was 18, and 12-month infant height-for-age z-scores (HAZ), −2.35. Structured observations were conducted over 6 months on 1649 breastfeeds during 3324 weekly daytime observations. Infants' and mothers' 24-h dietary recalls, weights, lengths/heights and mothers' arm circumferences were taken monthly. When plotted with age, infants' anthropometric z-scores, food energy, and minutes observed breastfeeding revealed three patterns in age periods: 5–12, 13–18, and 19–23 months. In periods one (breastfeeding high) and three (breastfeeding low), food energy increased with age, linear growth paralleled the World Health Organization (WHO) reference standard, and the children grew thinner. In two, (breastfeeding declining), food energy did not increase and growth stasis occurred. Longer observed breastfeeding accompanied in period one, low maternal arm circumference, low infant energy intake from complementary foods and infant shortness and plumpness in period two, infant shortness, thinness, and underweight; and in period three, infants energy and thinness. In conclusion, the paper suggests that growth stasis occurs primarily during the second period, which should have highest priority for culturally sensitive interventions.
Inelastic electron tunnelling spectroscopy—IV. A study of the formation of formic acid from atmospheric carbon dioxide and water within an Al—Aloxide—Pb tunnelling junction

Abstract Considerable confusion exists in the literature regarding the interpretation of peaks in the spectra of aluminium—aluminium oxide—lead tunnelling junctions doped with either water or water vapour. These peaks, which appear in the CH bend and stretch regions, have been variously assigned as trace organic impurities or as formic acid chemically produced within the tunnelling junction by a reaction between atmospheric carbon dioxide and the water dopant. The present work attempts to resolve this ambiguity by producing formic acid tunnelling spectra and comparing these with spectra produced from triply distilled water doped junctions. These spectra, which fingerprint exactly, have been assigned. Potential organic impurities in the water have been investigated by high resolution mass spectroscopy. The tunnelling spectrum of a junction electrode penetration doped with a suspension of calcium oxide in water has been produced and is assigned as calcium carbonate. It is suggested that a reaction takes place between calcium hydroxide and carbon dioxide adsorbed on the surface of the alumina to produce calcium carbonate. It is concluded that formic acid is produced within tunnelling junctions by a reaction between atmospheric carbon dioxide and water on the alumina surface.
A taxation policy toward capital, technology and long-run growth*

Incorporating the particular features of the U.S. tax code, notably corporate interest deductions and R&D expensing, into Romer's R&D-based endogenous growth model, we analyze how taxation of different-source capital income affects long-run growth by distorting saving, input demands, and stock market P/E ratios. Surprisingly, we find that a pro-growth tax system requires a lower income tax rate for noninnovative firms, particularly when R&D receives tax credits. Simulations for the U.S. economy provide the effects of taxation on growth, interest rates, P/E ratios, human capital allocations, and welfare.
Value at risk from econometric models and implied from currency options

This paper compares daily exchange rate value at risk estimates derived from econometric models with those implied by the prices of traded options. Univariate and multivariate GARCH models are employed in parallel with the simple historical and exponentially weighted moving average methods. Overall, we find that during periods of stability, the implied model tends to overestimate value at risk, hence over-allocating capital. However, during turbulent periods, it is less responsive than the GARCH-type models, resulting in an under-allocation of capital and a greater number of failures. Hence our main conclusion, which has important implications for risk management, is that market expectations of future volatility and correlation, as determined from the prices of traded options, may not be optimal tools for determining value at risk. Therefore, alternative models for estimating volatility should be sought. Copyright © 2004 John Wiley & Sons, Ltd.
Magnesium reduces free radical concentration and preserves left ventricular function after direct current shocks

Objective: Our objective was to determine if magnesium reduces free radicals generated by direct current countershock and preserves left ventricular contractile function. Background: We have previously shown that magnesium reduces free radicals in a coronary occlusion-reperfusion model, and therefore also might reduce free radical generation by direct current shocks. Methods: In eight swine weighing 18/27 kg (mean: 22 kg), using electron paramagnetic resonance, we monitored continuously the coronary sinus concentration of ascorbate free radical, a measure of free radical generation (total oxidative flux). Epicardial shocks (30 J) using a truncated exponential biphasic waveform (5/5 ms) were administered. Each animal received two shocks, one without and one with magnesium, 80 mg/min IV, beginning 10 min before the shock and continuing to 15 min after the shock. Percent fractional area shortening of the left ventricular cavity was determined by 2-dimensional echocardiography. Results: Magnesium shocks resulted in a significantly lower increase in the ascorbate free radical concentration (0.69 /4.6%) than no-magnesium shocks (169 /3.3%, P B/ 0.05) at 12 min after the shock. Total radical flux was reduced 72% (P B/0.05), and left ventricular fractional area shortening was preserved: baseline: 699 /2.6%, no-magnesium shocks: 419 /2.8% (P B/0.05, versus baseline) and magnesium shocks 619 /3.7%. Conclusions: Magnesium pre-treatment reduced oxygen free radicals generated by direct current shocks; post-shock left ventricular contractile function was not impaired. Magnesium may be cardioprotective during epicardial (‘surgical’) defibrillation. # 2002 Elsevier Science Ireland Ltd. All rights reserved.
Skin-Pigment Regulation of Vitamin-D Biosynthesis in Man Variation in solar ultraviolet at different latitudes may have caused racial differentiation in man

The known correlation between the color of human skin and latitude (Fig. 2) is explainable in terms of two opposing positive adaptations to solar ultraviolet radiation, weak in northern latitudes in winter yet powerful the year around near the equator. In northern latitudes there is selection for white skins that allow maximum photoactivation of 7-dehydrocholesterol into vitamin D at low intensities of ultraviolet radiation. In southern latitudes, on the other hand, there is selection for black skins able to prevent up to 95 percent of the incident ultraviolet from reaching the deeper layers of the skin where vitamin D is synthesized. Selection against the twin dangers of rickets on the one hand and toxic doses of vitamin D on the other would thus explain the world-wide correlation observed between skin pigmentation and nearness to the equator.
Multiuser Perspectives on Separated, On-Street Bicycle Infrastructure

In the early fall of 2009, the Bureau of Transportation in Portland, Oregon, installed a cycle track and a pair of buffered bike lanes in downtown Portland. A major objective was to test facilities that were thought to bring higher levels of comfort to bicycle riders through increased separation from motor vehicle traffic. After one year of use, an evaluation was conducted to determine how the facilities affected the experience of the various users. Intercept surveys of cyclists (n 5 248), motorists (n 5 262), pedestrians (n 5 198), and adjacent businesses (n 5 59) showed improved perceptions of safety and comfort among cyclists, particularly women. Cyclists also preferred the new facilities to alternative routes and facility types. Both motorists and cyclists liked the additional separation of users. Motorists were more likely to attribute additional travel delays and inconvenience to the facilities; this attitude was especially true for motorists who never rode a bicycle and those surveyed on the buffer...
Local Ancestry Corrects for Population Structure in Saccharomyces cerevisiae Genome-wide Association Studies

Genome-wide association studies (GWAS) have become an important method for mapping the genetic loci underlying complex phenotypic traits in many species. A crucial issue when performing GWAS is to control for the underlying population structure because not doing so can lead to spurious associations. Population structure is a particularly important issue in nonhuman species since it is often difficult to control for population structure during the study design phase, requiring population structure to be corrected statistically after the data have been collected. It has not yet been established if GWAS is a feasible approach in Saccharomyces cerevisiae, an important model organism and agricultural species. We thus performed an empirical study of statistical methods for controlling for population structure in GWAS using a set of 201 phenotypic traits measured in multiple resequenced strains of S. cerevisiae. We complemented our analysis of real data with an extensive set of simulations. Our main result is that a mixed linear model using the local ancestry of the strain as a covariate is effective at controlling for population structure, consistent with the mosaic structure of many S. cerevisiae strains. We further studied the evolutionary forces acting on the GWAS SNPs and found that SNPs associated with variation in phenotypic traits are enriched for low minor allele frequencies, consistent with the action of negative selection on these SNPs. Despite the effectiveness of local ancestry correction, GWAS remains challenging in highly structured populations, such as S. cerevisiae. Nonetheless, we found that, even after correcting for population structure, there is still sufficient statistical power to recover biologically meaningful associations.