cssi/SciSciGPT-SciSciNet huggingface dataset:
Surgical Site Infection After Autologous Cranioplasty for Decompressive Craniectomy in Traumatic Brain Injury: A Retrospective Review of Two Level 1 Trauma Centers

Object Surgical site infection (SSI) after cranioplasty can result in unnecessary morbidity. This analysis was designed to determine the risk factors of SSI after cranioplasty in patients who received a decompressive craniectomy with the autologous bone for traumatic brain injury (TBI). Methods A retrospective review was performed at two level 1 academic trauma centers for adult patients who underwent autologous cranioplasty after prior decompressive craniectomy for TBI. Demographic and procedural variables were collected and analyzed for associations with an increased incidence of surgical site infection with two-sample independent t tests and Mann Whitney U tests, and with a Bonferroni correction applied in cases of multiple comparisons. Statistical significance was reported with a P value of Results A total of 71 patients were identified. The mean interval from craniectomy to cranioplasty was 99 days (7-283), and 3 patients developed SSIs after cranioplasty (4.2%). Postoperative drain placement (P > 0.08) and administration of intrawound vancomycin powder (P = 0.99) were not predictive of infection risk. However, a trend was observed suggesting that administration of prophylactic preoperative IV vancomycin is associated with a reduced infection rate. Conclusions The SSI rate after autologous cranioplasty in TBI patients is lower than previously reported for heterogeneous groups and indications, and the infection risk is comparable to other elective neurosurgical procedures. As such, the authors recommend attempting to preserve native skull and perform autologous cranioplasty in this population whenever possible.
Assessment of Cognitive Function in Patients After COVID-19 Infection.

People who have survived COVID-19 frequently complain of cognitive dysfunction, which has been described as brain fog. The prevalence of post–COVID-19 cognitive impairment and the association with disease severity are not well characterized. Previous studies on the topic have been limited by small sample sizes and suboptimal measurement of cognitive functioning.1 We investigated rates of cognitive impairment in survivors of COVID-19 who were treated in outpatient, emergency department (ED), or inpatient hospital settings.
Some thoughts on the implementation of water quality management strategies for Central and Eastern Europe

The countries of Central and Eastern Europe (CEE) continue their efforts to address environmental problems, including water quality management, in the context of a transition from the centrally planned to market economies. Their economic recovery and further development is the most pressing and central goal since water quality deterioration is nothing but one of the many consequences of the lack of economic progress. Since international assistance to the CEE countries is limited, an early action should be taken to support the establishment of national financial mechanisms and incentives. To improve water quality, the efficiency of water, energy and material use must be increased in the CEE countries; reducing water use is an imperative. Industrial wastewater management strategy shall distinguish between the old and new enterprises. The non-point pollution sources of agricultural character should largely be controlled by preventive measures, applied jointly by land, water and agricultural specialists and managers. Transformation of industry and agriculture and water quality improvements must be undertaken together.
Egyptian Fiscal History in a World of Warring States, 664–30 bce

From China to the Mediterranean, interstate competition transformed the political, economic, and social order in the mid-first millennium bce. The case of Egypt from the Saite reunification in 664 bceto the Roman conquest in 30 bceillustrates this phenomenon, which resembles the rise of fiscal-military states under the pressure of war in early modern Europe. The New Fiscal History that has sought to explain this rise in Europe tends to produce a linear historical account of centralization and increasing fiscal capacity from feudal societies to the modern tax state. In Egypt, by contrast, the process was interrupted by integration into the imperial structures of Achaemenid Persia and Rome. It thus provides a convenient laboratory to compare the development of fiscal institutions in a political environment characterized by warring states, and one dominated by a single empire.
Gonadal Steroids Promote Glial Differentiation and Alter Neuronal Morphology in the Developing Hypothalamus in a Regionally Specific Manner

One of the more striking sexual dimorphisms in the adult brain is the synaptic patterning in some hypothalamic nuclei. In the arcuate nucleus (ARC) males have twice the number of axosomatic and one-half the number of axodendritic spine synapses as females. The opposite pattern is observed in the immediately adjacent ventromedial nucleus (VMN). In both cases, early exposure to testosterone dictates adult dimorphism, but the exact timing, mechanism, and site of steroid action remain unknown. Astrocytes also exhibit sexual dimorphisms, and their role in mediating neuronal morphology is becoming increasingly evident. Using Golgi-Cox impregnation to examine neuronal morphology and glial fibrillary acidic protein immunoreactivity (GFAP-IR) to characterize astrocytic morphology, we compared structural differences in dendrites and astrocytes from the ARC and VMN in postnatal day 2 rat pups from four hormonally different groups. Consistent with previous observations, testosterone exposure induced a rapid and dramatic stellation response in ARC astrocytes. Coincident with this change in astrocytic morphology was a 37% reduction in the density of dendritic spines on ARC neurons. In contrast, astrocytes in the VMN were poorly differentiated and did not respond to testosterone exposure, nor were there any changes in neuronal dendrite spine density. However, VMN neurons exposed to testosterone had almost double the number of branches compared with that in controls. These data suggest that the degree of maturation and the differentiation of hypothalamic astrocytes in vivo are correlated with the ability of neurons to sprout branches or spines in response to steroid hormones and may underlie regionally specific differences in synaptic patterning.
Mutations in a gene encoding a new Hsp70 suppress rapid DNA inversion and bgl activation, but not proU derepression, in hns-1 mutant Escherichia coli.

Abstract Mutations in hns, the gene encoding the nucleoid-associated protein H-NS, affect both the expression of many specific unlinked genes and the inversion rate of the DNA segment containing the pilA promoter in Escherichia coli. A second-site mutation, termed hscA1, compensated for the effect of an hns-1 mutant allele on the pilA promoter inversion rate and on activation of the bgl operon. The proU operon, induced in an hns-1 background, remained derepressed in an hns-1 hscA1 strain and was induced at an intermediate level in an hns hscA1 strain. An insertion mutant allele, hscA2-cat, conferred the same partial hns-1 compensatory phenotype as the hscA1 allele. The hscA gene encoded a 66-kDa protein product that is a member of the Hsp70 protein class. The gene encoding this product is part of a bicistronic operon that is preceded by a possible sigma 32 promoter and also encodes a 21-kDa protein with significant homology to the DnaJ protein family. The mutation defining the hscA1 allele resulted in a phenylalanine substituting a conserved serine residue located in the ATP-binding region of other Hsp70 proteins.
Escalation of the Study-Abroad Experience: Lessons from a Hyper-Intensive Integrated Learning Program

Abstract The authors discuss an innovative study-abroad program implemented by a large university in the Midwestern United States. In partnership with a French business school, a program was established incorporating project-based learning, a multi-national student population, and a three-month residency in France by U.S.-based students and faculty. Specific examples are discussed, and recommendations made, with respect to curricular issues, partner selection, technological issues, institutional support, contingency planning, and daily living. The results of an open-ended survey of student participants are also discussed.
STABILITY OF DEVELOPING PIPE FLOW SUBJECTED TO NON-AXISYMMETRIC DISTURBANCES

The linear stability of the developing flow of an incompressible fluid in the entrance region of a circular tube is investigated. The case of non-axisymmetric small disturbances is considered in the analysis. The main-flow velocity distribution used in the stability calculations is that from the solution of the linearized momentum equation. The eigenvalue problem consisting of the disturbance equations and the boundary conditions is solved by a direct numerical integration scheme along with an iteration procedure. The flow is found to be unstable to nonaxisymmetric disturbances with an azimuthal wavenumber of one. Neutral-stability curves and critical Reynolds numbers at various axial locations are presented.
The pharmacokinetic basis of oral valacyclovir treatment of herpes simplex virus (HSV) or varicella zoster virus (VZV) meningitis, meningoencephalitis or encephalitis in adults

Encephalitis is defined as an infection of the brain with mental confusion but without nuchal rigidity.1 Meningoencephalitis is an infection of leptomeninges in the brain with nuchal rigidity and m...
Noise-trader risk: does it deter arbitrage, and is it priced?

Arbitrage positions that benefit from the reversion of closed-end fund discounts to rational levels show excess returns that increase in magnitude the more funds are mispriced. At the same time, fund trading volumes and bid-ask spreads more than double as funds become increasingly mispriced. These behaviors suggest that non-diversifiable noise-trader risk increases the more funds are mispriced and that market participants are not only aware of this unique risk factor but demand a compensatory rate of return that varies with its magnitude.
Chapter 5 Behavior of Fishes in the Sexual/Unisexual Mating System of the Amazon Molly (Poecilia formosa)

A bstract One of the most exciting questions in evolutionary biology remains to try to understand the maintenance and evolution of recombination. To address the second question, one can use comparisons of sexual species with a closely related asexual species. Such a species pair exists in a group of live‐bearing fishes, the mollies. In this taxon a unisexual fish was formed via hybridization. The result of this instantaneous speciation was the Amazon molly ( Poecilia formosa ), which is a very unusual species: it shows clonal reproduction, has essentially no males of their own species, but requires sperm from heterospecific males for successful reproduction. Especially this feature, which has been dubbed sexual parasitism, is intriguing because it connects the females of at least two different species and likely forces them to compete over males. This makes them excellent models for studying the maintenance of recombination and the coexistence of species in nature, but mainly one can explore the behavioral dynamics within this species and between Amazon mollies and their sexual hosts. Several important aspects emerged from studying this unique mating system. In the mating system of the Amazon molly, for example, the role of male mate choice is relatively well studied, and this whole field is now emerging in other mating systems as well. Likewise female choice, sexual conflict, and importantly nonindependent mate choice have been successfully studied using Amazon mollies.
Stable H/sup /spl infin// extensions of hybrid control systems

Hybrid control systems (HCS) arise when the plant, a continuous state system (CSS), is controlled by a discrete event system (DES) controller. It is assumed that there exists a specification on the plant's desired symbolic behaviour which describes how various operational modes of the controlled plant should fit together. One design problem involves determining an HCS that "realizes" the specified behaviour in a "stable" manner. The solution of this problem involves finding a sequence of subgoals and controllers achieving the specified behaviour in a "logically" stable manner. This paper shows how such a "stable" extension can be constructed using multiple H/sup /spl infin// control systems exhibiting robust stability.
The evolution of DNA computing: nature's solution to a path problem

How do cells and nature "compute"? They read and "rewrite" DNA all the time, by processes that modify sequence at the DNA or RNA level. Adleman (1994) reported an elegant solution to a seven city directed Hamiltonian path problem using DNA. This launched the new field of DNA computers, which in four years has become an international focus. However, unknown to Adleman and this field, two ciliated protozoans of the genus Oxytricha had solved an even harder problem using DNA several million years earlier. In general, the processes of gene unscrambling and editing present two of nature's ingenious solutions to the problem of gene assembly.
Recent insights into cell death and autophagy

Macroautophagy (hereafter autophagy) is an evolutionarily-ancient mechanism by which cellular material is delivered to lysosomes for degradation. Autophagy and cell death are intimately linked. For example, both processes often use the same molecular machinery and recent work suggests that autophagy has great influence over a cell's decision to live or die. However, this decision-making is complicated by the fact that the role of autophagy in determining whether a cell should live or die goes both ways: autophagy inhibition can result in more or less cell death depending on the death stimulus, cell type or context. Autophagy may also differentially affect different types of cell death. In the present review, we discuss the recent literature that helps make sense of this apparently inconsistent role of autophagy in influencing a cell to live or die.
The Status of Law and Lawmaking Procedure under the Kuomintang 1925–46

The initial reaction of the foreigner upon his first contact with Chinese law and legal system is one of frustration and noncomprehension. Those given to facile generalization are apt to declare either that China is devoid of any serious juridical tradition or that it is still in a primitive state of legal development. But both of these conclusions are clearly false since the Middle Kingdom has a long and complex legal history, and, while certain jural notions of responsibility which characterize Western law have not come into being in the East, their absence is not proof of arrested growth but merely that jural problems are envisaged in another fashion in the Sinitic body politic. The basic fact which the foreigner slowly comes to recognize is that, while the need for justice is constant in any culture, in Chinese society it is attained in a unique fashion.
Simultaneous control of intermediate diabetes outcomes among Veterans Affairs primary care patients.

BACKGROUND: Guidelines recommend tight control of hemoglobin Alc (HbAlc), low-density lipoprotein cholesterol (LDL-C), and blood pressure (BP) for patients with diabetes. The degree to which these intermediate outcomes are simultaneously controlled has not been extensively described.
On the measure of dislocation densities from diffraction line profiles: A comparison with discrete dislocation methods

Abstract In this work the accuracy and range of applicability of peak broadening models, from which dislocation densities can be extracted, is studied. For that purpose dislocation microstructures are generated via a discrete dislocation dynamics method and the internal elastic strains within the simulated volume are calculated. Diffraction peaks are generated from the simulations and a whole pattern line profile analysis method based on the Wilkens model is used to quantify the dislocation densities associated with the simulated microstructures. The work is applied to the case of face-centered cubic crystals deforming in coplanar slip. The accuracy of the analytical models is quantified by considering realistic three-dimensional microstructures containing curved dislocations with a specified distribution. The dependence and sensitivity of the analytical models upon dislocation density and long-range order are investigated. It was found that, provided the distribution of dislocations is rather homogeneous, line profile analysis provides fairly accurate predictions of the dislocation density.
A contribution to the taxonomy of Piptadenia (Mimosaceae) in South America

Four new species ofPiptadenia are described:P. anolidurus (from Amazonian Ecuador, Peru and Brazil),P. buchtienii (from trans-Andean Bolivia),P. cuzcoensis (from southern Peru), andP. imatacae (from Venezuelan Guayana); andP. adiantoides var.peruviana J. F. Macbr. is raised in rank toP. peruviana. In relation toP. imatacae the transfer ofP. uaupensis Benth. andP. floribunda Kleinhoonte toAdenopodia Presl is shown to be ill-advised. The affinities of each new species are discussed and critical characters are illustrated.Mimosa tessmanii Harms is newly synonymized withP. uaupensis.
Design of a K- thru Ka-band modified Butler matrix feed for a 4-arm spiral antenna

A computational model of a wideband μ-coaxial based modified 4×4 Butler matrix feed network for a four-arm spiral antenna is discussed in this paper. Each component within the Butler matrix is fully characterized using the finite element method and their performance is compared with the commercially available counterparts. A method of moments model of a four-arm spiral antenna for 18–40 GHz is also developed and used to determine the effects of the Butler matrix feed on the antenna pattern purity. The designed Butler matrix is 22 × 20 × 1 mm (L × W × H) in size and operates over the entire 18–40 GHz range.
Applying the Bio-Ecological Model of Intelligence to the Wechsler Scales in The Bahamas

This paper contains information about theory and application of the bio-ecological model of intelligence by Sharon Gopaul-McNicol. The validity, reliability and normative samples of the Wechsler scales will be described. Examples of how this model is applied to the Wechsler scales will be demonstrated. Emphasis will be placed on children of varying cultures living in the Bahamas. Twenty-nine Bahamian children completed the Wechsler Intelligence Scale for Children, Third Edition (WISC-III) in The Bahamas using the bio-ecological model of intelligence. This small sample revealed that once this model was utilized the Bahamian children improved their intelligence quotient (IQ).
LOCAL SPECIFIC THERAPY OF EXPERIMENTAL PNEUMOCOCCAL MENINGITIS : IV. TYPE II PNEUMOCOCCAL MENINGITIS IN DOGS.

1. With properly selected strains of Type II pneumococci, fatal meningitis may be produced by intrathecal infection in dogs. 2. The pathology of the disease differs from that produced by Type I pneumococci, at least with the strains employed. 3. Type II meningitis is characterized by early, very marked reactions, a very heavy fibrin exudation, and a tendency toward the rapid establishment of blocks. 4. Extreme vasodilatation and. hemorrhage are common. 5. The fibrinopurulent exudate tends to involve the walls and perivascular sheaths of deeply penetrating vessels, thereby causing thrombosis. 6. Thrombosis leads to foci of parenchymatous softening which, on subsequent infection, become brain abscesses. 7. The lateral venticles are a "point of election" for the luxuriant growth of pneumococci. Conversely there is evidence that Type II organisms tend somewhat to disappear from other regions, owing either to spontaneous phagocytosis or to filtration into the blood stream. The lateral ventricles, however, continually renew the supply. 8. Hydrocephalus occurs early-sometimes during the 2nd day of the disease. 9. Central myelitis is common and appears early in the disease. 10. Deep nerve cell lesions with necrosis and neuronophagia are encountered. Their pathology suggests a toxic source. 11. In most cases treatment has been impossible owing to severe early reactions, and only as a prophylactic has optochin-serum therapy any real value. It delays death, but has in no instance cured established disease in the dog. 12. Systemic generalization of Type II meningeal infection in the dog occurs, but it is rarely of sufficient extent to modify prognosis.
Coordinated expression between two photosynthetic petunia genes in transgenic plants

We examined the divergent Cab22R and Cab22L genes of petunia as a coupled photosynthetic promoter casstte for simultaneously directing high level expression of two foreign genes in a coordinated and tissue specific manner in transgenic plants. Primer extension assays with gene specific primers on petunia leaf RNA indicated that abundant and coordinated mRNA expression occurs for the two Cab22 divergent transcription units in a tissue specific and light regulated fashion. The expression characteristics of the intact Cab22 genes can be maintained in transgenic tobacco plants, but are influenced by the site of insertion into the Agrobacterium T-DNA binary vector. Thus, the expression levels of genes introduced near the T-DNA left border varied coordinatedly among independently transformed plants and remained completely light inducible and tissue specific. In contrast, each of these transcription properties was significantly disrupted by the insertion of the genes into the right section of the binary vector, between a selectable NPTII gene and the T-DNA octopine synthase (Ocs) cis-acting promoter element. Gene transfer experiments with chimeric gene constructs have shown that both the quantitative and qualitative expression properties of the Cab22 genes can be conferred to foreign protein coding genes via fusion to the Cab22 leader and upstream sequences. The use of this divergent promoter as a cassette to express foreign genes in plants in a coordinated fashion and the possible influences of differential mRNA stabilities and transcription rates between intact and chimeric genes in transgenic plants are discussed.
Between-theory and within-theory conflict in explaining context effects in impression formation ☆

Abstract Research on context effects in impression formation has taken the form of testing competing predictions from the averaging model and the meaning shift model. This between-theory conflict has been unprofitable because neither theory has yet acquired the degree of specificity necessary to generate unequivocal predictions in this area. The research has been useful, however, in identifying each theory's capacity to generate self-contradictory predictions. Future research on this topic can most profitably be addressed to resolving these within-theory conflicts.
Dry pants: a rapid method of toilet training children.

Abstract Toilet training sometimes requires considerable time. An intensive learning procedure was devised for shortening this training time and tested with 34 children who were experiencing toilet training problems. The procedure had the following major characteristics: (1) a distraction-free environment, (2) an increased frequency of urination by increased fluid intake, (3) continuous practice and reinforcement of the necessary dressing skills, (4) continuous practice and reinforcement in approaching the toilet, (5) detailed and continuing instruction for each act required in toileting, (6) gradual elimination of the need for reminders to toilet, (7) immediate detection of accidents, (8) a period of required practice in toilet-approach after accidents as well as (9) negative reinforcement for the accident, (10) immediate detection of correct toileting, (11) immediacy of reinforcement for correct toiletings, (12) a multiple reinforcement system including imagined social benefits as well as actual praise, hugging and sweets, (13) continuing reinforcement for having dry pants, (14) learning by imitation, (15) gradual reduction of the need for immediate reinforcement and (16) post-training attention to cleanliness. All 34 children were trained and in an average of 4 hr; children over 26 months old required an average of 2 hr of training. After training, accidents decreased to a near-zero level and remained near zero during 4 months of follow-up. The results suggest that virtually all healthy children who have reached 20 months of age can be toilet trained and within a few hours.
Digital Radiography in Equine Practice

Digital radiography (DR) is a relatively new imaging modality that has recently become available for routine equine imaging. Like a digital camera, the image is visible within seconds of exposure without the need for chemical film processing or laser scanning a phosphor-based imaging cassette. The principal advantage of digital radiography over film/screen systems or computed radiography (CR) is the increased speed and efficiency of obtaining radiographs and immediate image preview. Two other general advantages are a wide exposure latitude as well as superior image quality from postprocessing, which primarily enhances spatial and contrast resolution. The ability to rapidly review, archive, and transmit digital images is also advantageous. Large studies can be displayed and organized by patient information and date with “the click of a mouse.” When displaying digital radiographs, a user can adjust the properties of an image to change parameters such as brightness, contrast, and magnification. The images and associated patient information can be securely archived with PACS (Picture Archiving and Communication System) or written to portable digital media such as CD-ROM or DVD. Digital radiographs can be sent electronically to other veterinarians for additional evaluation, which improves turnaround times for second opinions or prepurchase exams. However, the security of archiving and transmitting digital images needs serious consideration in equine practice and is best discussed with a computer security expert. The disadvantages of digital radiography are the initial cost and the potential risk of damage to expensive equipment. Nonetheless, some equine practices report that the increased efficiency of DR ultimately leads to greater revenue. In addition, extra care and common sense when handling an animal greatly reduce the risk of equipment damage. An equine practitioner considering DR needs to assess the advantages of increased efficiency and improved image quality against the considerable investment in new technology and the risk of equipment damage. Furthermore, the prospective buyer must carefully evaluate the different quality parameters, features, and ease of use.
Meta-Analysis of the Effect of Cardiac Rehabilitation Interventions on Depression Outcomes in Adults 64 Years of Age and Older

Heart disease is a major cause of hospitalization and is associated with greater impairment than arthritis, diabetes mellitus, or lung disease. Depression is prevalent and a serious co-morbidity in heart disease with negative consequences including higher levels of chronic physical illness, decreased psychological well-being, and increased health care costs. The objective of the study was to examine with meta-analysis the impact of community-based cardiac rehabilitation (CR) treatment on depression outcomes in older adults. Randomized controlled trials comparing patients (≥64 years old) receiving CR to cardiac controls were considered. Meta-analyses were based on 18 studies that met inclusion criteria, comprising 1,926 treatment participants and 1,901 controls. Effect sizes (ESs) ranged from −0.39 (in favor of control group) to 1.09 (in favor of treatment group). Mean weighted ES was 0.28, and 11 studies showed positive ESs. Meta-analysis suggests that most CR programs delivered in the home can significantly mitigate depression symptoms. Tailored interventions combined with psychosocial interventions are likely to be more effective in decreasing depression in older adults with heart disease than usual care.
Application of digital terrain data to quantify and reduce the topographic effect on Landsat data

Integration of LANDSAT multispectral scanner (MSS) data with 30 m U.S. Geological Survey (USGS) digital terrain data was undertaken to quantify and reduce the topographic effect on imagery of a forested mountain ridge test site in central Pennsylvania. High Sun angle imagery revealed variation of as much as 21 pixel values in data for slopes of different angles and aspects with uniform surface cover. Large topographic effects were apparent in MSS 4 and 5 was due to a combination of high absorption by the forest cover and the MSS quantization. Four methods for reducing the topographic effect were compared. Band ratioing of MSS 6/5 and MSS 7/5 did not eliminate the topographic effect because of the lack of variation in MSS 4 and 5 radiances. The three radiance models examined to reduce the topographic effect required integration of the digital terrain data. Two Lambertian models increased the variation in the LANDSAT radiances. The nonLambertian model considerably reduced (86 per cent) the topographic effect in the LANDSAT data. The study demonstrates that high quality digital terrain data, as provided by the USGS digital elevation model data, can be used to enhance the utility of multispectral satellite data.
Leaching of quartz from precambrian hypabyssal rhyolite porphyry, Llano County, Texas

A Precambrian hypabyssal rhyolite porphyry in central Texas has retained its original texture, although alkali feldspar phenocrysts have inverted and unmixed from zoned, single-phase high-temperature feldspar to zoned microperthite with an intermediate microcline host.
Behavioral contrast resulting from a change in sucrose concentration

Three rats were trained to respond on a two-component multiple schedule, with identical variable-interval 1.5-min components for 32% sucrose reinforcement. Subsequent reduction in the sucrose concentration of reinforcement to 8% in one component resulted in positive behavioral contrast for two Ss. Response rate facilitation was observed in both components for the third S.
Paleontology: A New Burgess Shale Fauna

A spectacular Cambrian soft bodied fauna some 40 km from Walcott's original Burgess Shale locality includes over 50 taxa, some 20% new to science. New anatomical evidence from this site will illuminate the evolution of early marine animals.
Theoretical analysis of supercontinuum and coloured conical emission produced during ultrashort laser pulse interaction with gases

We use a conceptually new approach to theoretical modelling of self-focusing in which we integrated diffractive and geometrical optics in order to explain and predict emission of white light and coloured rings observed in ultrashort laser pulse interaction. In our approach, laser beam propagation is described by blending the solution of the linear Maxwell's equation and a correction term that represents nonlinear field perturbation expressed in terms of paraxial ray-optics (eikonal) equation. No attempt is made to create an appearance of exhaustive treatment via use of complex mathematical models. Rather, emphasis is placed on elegance of the formulations leading to fundamental understanding of the underlying physics and, eventually, to an accurate practical numerical model capable of simulating white light generation and conical emission of coloured rings produced around the filament.
Improvements to a nonequilibrium algebraic turbulence model

It has been noted that while the nonequilibrium turbulence model of Johnson and King (1985, 1987) performed significantly better than alternative methods, differences between predicted and observed shock locations for certain weak interactions are produced due to a defficiency in the model's inner eddy viscosity formulation. A novel formulation for the model is presented which removes this deficiency, while satisfying the law of the wall for adverse pressure-gradient conditions better than either the original formulation or mixing-length theory.
Autonomous terrain parameter estimation for wheeled vehicles

This paper reports a methodology for inferring terrain parameters from estimated terrain forces in order to allow wheeled autonomous vehicles to assess mobility in real-time. Terrain force estimation can be used to infer the ability to accelerate, climb, or tow a load independent of the underlying terrain model. When a terrain model is available, physical soil properties and stress distribution parameters that relate to mobility are inferred from vehicle-terrain forces using multiple-model estimation. The approach uses Bayesian statistics to select the most likely terrain parameters from a set of hypotheses, given estimated terrain forces. The hypotheses are based on the extensive literature of soil properties for soils with cohesions from 1 - 70 kPa. Terrain parameter estimation is subject to mathematical uniqueness of the net forces resulting from vehicle-terrain interaction for a given set of terrain parameters; uniqueness properties are characterized in the paper motivating the approach. Terrain force and parameter estimation requires proprioceptive sensors - accelerometers, rate gyros, wheel speeds, motor currents, and ground speed. Simulation results demonstrate efficacy of the method on three terrains - low cohesion sand, sandy loam, and high cohesion clay, with parameter convergence times as low as .02 sec. The method exhibits an ability to interpolate between hypotheses when no single hypothesis adequately characterizes the terrain.
1-alkene-1,1-diboronic esters and 1,1-bis(chloromercuri)-1-alkenes

Abstract Several 1,1-bis(trimethylenedioxyboryl)-1-alkenes (II) have been prepared and converted efficiently to 1,1-bis(chloromercuri)-1-alkenes (III) by reaction with mercuric chloride and sodium acetate in aqueous methanol. Preparations of a 1,1-diiodo-1-alkene (IV) and three 1,1-bis(ethylenedioxyboryl)-1-alkenes are also described.
Gold(I) tris(mercaptoimidazolyl)borate chemistry: Synthesis and molecular structure of the first trinuclear TmR complex of a transition metal

Abstract The first trinuclear transition metal tris(mercaptoimidazolyl)borate complexes, the gold(I) derivatives [Au3(TmtBu)2]X (X = Cl, BF4, PF6, SbF6) have been prepared and fully characterized using a combination of analytical and spectroscopic techniques. The X-ray structure of the hexafluoroantimonate salt confirmed the presence of a novel cationic complex [Au3(TmtBu)2]+ in which a triangular array of three gold atoms is coordinated simultaneously by two TmtBu ligands. The three gold centers exhibit roughly linear coordination and the intermetallic distances suggest the presence of weak aurophilic interactions between them.
Use of freshwater rotifer Brachionus calyciflorus in screening assay for potential endocrine disruptors

Reports of the effects of endocrine disruptors on aquatic invertebrates are becoming increasingly common. However, little is known about the endocrine systems of most aquatic invertebrates, limiting the development of assays based on endocrine mechanisms. As a result, endocrine disruption is often inferred through the effects caused by the chemical of interest, making it difficult to rule out other mechanisms of toxicity. To be a good candidate for an endocrine disruptor, effects should be observed in processes known to be under endocrine control, at life stages where endocrine signals are known to be active, and at concentrations below acute and chronic toxic effects. We developed a 96-h reproductive assay using the freshwater rotifer Brachionus calyciflorus to screen for potential endocrine disruptors and examined cadmium, chlorpyrifos, naphthol, pentachlorophenol, estradiol, methoprene, precocene, nonylphenol, flutamide, and testosterone for effects on asexual and sexual reproduction. Flutamide, testosterone, and nonylphenol inhibited fertilization of sexual females at concentrations of 1, 10, and 50 μg/L, respectively. The fertilization no-observable-effect concentrations (NOECs) for these compounds were 5 to 200 times lower than previously described reproduction NOECs for B. calyciflorus Sexual reproduction was inhibited with no effects on asexual reproduction, increasing the likelihood that these specific reproductive effects occurred through an endocrine mechanism. Rotifer reproduction assays may be a useful, rapid, and inexpensive method for screening compounds suspected to have endocrine disrupting activity in aquatic invertebrates.
Toward Efficient Analysis of >70 kDa Proteins with 100% Sequence Coverage:

For complete characterization of larger proteins, primary structural analysis by mass spectrometry must be made more efficient. A straightforward approach is illustrated here using two proteins of 159 and 199 kDa with five and nine lysine (Lys) residues, respectively. These proteins were degraded by Lys-C to mixtures of peptides ranging in size from 5 to 48 kDa, whose multiply-charged ions (from electrospray ionization) are far more amenable than the intact proteins to direct interrogation in a Fourier-transform mass spectrometer. For the 199 kDa PchF of ∼ 60% purity, an unfractionated Lys-C digest gave 106 isotopic distributions from 71 components (most of which were below 6 kDa); 15% sequence coverage was obtained. For the > 90% pure PchE (159 kDa), complete sequence coverage was obtained from six Lys-C peptides of 5, 8, 26, 32, 40 and 48 kDa, with all but the largest of these measured at isotopic resolution on a 4.7 Tesla instrument. Practical strategies for implementing this characterization strategy ...
Isolation of the human anionic glutathione S-transferase cDNA and the relation of its gene expression to estrogen-receptor content in primary breast cancer.

Abstract The development of multidrug resistance in MCF7 human breast cancer cells is associated with overexpression of P-glycoprotein, changes in activities of several detoxication enzymes, and loss of hormone sensitivity and estrogen receptors (ERs). We have cloned the cDNA for one of the drug-detoxifying enzymes overexpressed in multidrug-resistant MCF7 cells (AdrR MCF7), the anionic isozyme of glutathione S-transferase (GST pi). Hybridization with this GST pi cDNA, GST pi-1, demonstrated that increased GST pi activity in AdrR MCF7 cells is associated with overexpression but not with amplification of the gene. We mapped the GST pi gene to human chromosome 11q13 by in situ hybridization. Since multidrug resistance and GST pi overexpression are associated with the loss of ERs in AdrR MCF7 cells, we examined several other breast cancer cell lines that were not selected for drug resistance. In each of these cell lines we found an inverse association between GST pi expression and ER content. We also examined RNA from 21 primary breast cancers and found a similar association between GST pi expression and ER content in vivo. GST pi mRNA content in 11 ER-positive tumors (less than or equal to 10 fmol/mg of protein) was significantly different from the GST pi content of 10 ER-negative tumors (P = 0.002; Mann-Whitney Wilcoxon test for two independent samples). The finding of similar patterns of expression of a drug-detoxifying enzyme and of ERs in vitro as well as in vivo suggests that ER-negative breast cancer cells may have greater protection against antineoplastic agents conferred by GST pi than ER-positive tumors.
Aggregate returns to scale and embodied technical change: theory and measurement using stock market data☆

Abstract We develop a new general equilibrium growth accounting framework that features increasing returns to scale, imperfect competition and incorporates technological revolutions into the description of technical progress. We propose a way to tell apart revolutionary changes in technology and incremental innovations using stock market data. We use our framework to jointly estimate the overall embodied TFP change during 1953–1995 and the aggregate output elasticity. We find that the IT revolution raised the aggregate TFP level by about 20%. We suggest a 1.09–1.11 range for the aggregate returns to scale.
Fuelwood, deforestation, and land degradation: 10 years of evidence from cebu province, the Philippines

A major development concern of the 1970s and 1980s was ‘the other energy’ or ‘woodfuel crisis’. Woodfuel use in developing regions of Africa, Asia, and Latin America was believed to be a key factor in tropical deforestation, and the loss of forests was projected to result in widespread woodfuel shortages. In recent years, however, it has become apparent that woodfuel production is seldom a direct cause of deforestation (although it may be a by-product), and that most woodfuel demand is met by trees and shrubs growing outside of forest areas. In addition, earlier predictions of serious woodfuel shortages have not materialized. But in some regions, including the Philippines, woodfuel use is still regularly pointed to as a primary cause of deforestation, and woodfuel shortages are still predicted for the immediate future. In particular, commercial woodfuel demand for household and commercial use is said to be contributing to over-exploitation of forest resources. This paper examines the connections between commercial woodfuel demand and deforestation on the Island of Cebu in the central Philippines. Cebu is widely perceived as an environmental disaster area on the brink of ecological collapse, and tree cutting for woodfuel production is often blamed for contributing to this condition. In contrast, this paper will argue that environmental conditions on Cebu are improving, that tree planting and management is widespread among smallholder farmers and other landowners, and that commercial demand for woodfuel and other wood products is one of the main factors driving increased reforestation on the island. Copyright © 2008 John Wiley & Sons, Ltd.
Probing backbone hydrogen bonds in the hydrophobic core of GCN4.

Backbone amide hydrogen bonds play a central role in protein secondary and tertiary structure. Previous studies have shown that substitution of a backbone ester (−COO−) in place of a backbone amide (−CONH−) can selectively destabilize backbone hydrogen bonds in a protein while maintaining a similar conformation to the native backbone structure. The majority of these studies have focused on backbone substitutions that were accessible to solvent. The GCN4 coiled coil domain is an example of a stable α-helical dimer that possesses a well-packed hydrophobic core. Amino acids in the a and d positions of the GCN4 helix, which pack the hydrophobic core, were replaced with the corresponding α-hydroxy acids in the context of a chemoselectively ligated heterodimer. While the overall structure and oligomerization state of the heterodimer were maintained, the overall destabilization of the ester analogues was greater (average ΔΔG of 3+ kcal mol-1) and more variable than previous studies. Since burial of the more hydr...
An evaluation of youth empowerment tobacco prevention programs in the Southwest.

Evaluation research pertaining to the development of assessment instruments that fully capture the facets of empowerment prevention perspectives among youth are sparse. With funding from the American Legacy Foundation, the University of New Mexico Center for Health Promotion and Disease Prevention, in partnership with the New Mexico State Department of Health, developed a measure of individual empowerment. Drawing from the various bodies of literature in adolescent development, substance abuse prevention, and program/coalition building, a questionnaire was developed to capture facets of individual empowerment as it pertains to tobacco prevention efforts among youth within New Mexico. Utilizing a sample of 112 youth participants, principal axis factor analysis with Varimax rotation revealed four valid sub-scales entitled active participation, empowerment efficacy, external organizational involvement, and participant satisfaction. Internal consistency reliabilities were satisfactory with Cronbach's alpha ra...
Induction of DNA-protein cross-links in Chinese hamster cells by the photodynamic action of chloroaluminum phthalocyanine and visible light.

— Chloroaluminum phthalocyanine (CAPC) is an efficient photosensitizer for the inactivation of Chinese hamster V79 cells. In order to investigate possible molecular mechanisms in the photo-dynamic action of CAPC and visible light, the induction and repair rate of two classes of DNA lesions have been determined, i.e. DNA single-strand breaks and DNA-protein cross-links. In cells pretreated with 1 μ.M CAPC, a fluence of 12 kJ/m2 of red light (>600 nm) kills approximately 50% of the cells and induces 3 to 3.5 Gy-equivalents of single-strand breaks. The repair of these breaks was slower than the repair of single-strand breaks induced by m-irradiation. The photodynamic action of CAPC also induces a large number of DNA-protein cross-links which, in contrast to m-radiation-induced DNA-protein cross-links, do not appear to be repaired during 4 h of post-treatment incubation in fresh medium. These studies suggest that DNA may be an important target for the cytotoxicity of CAPC + red light.
Ultrasound assessment of angiogenesis in a matrigel model in rats

Matrigel, a basement membrane extract, has been extensively used in in vivo angiogenesis. Contrast ultrasound imaging (CUI) of implanted Matrigel plugs with (+bFGF) and without basic fibroblast growth factor (-bFGF) was performed 7 and 14 d after implantation, followed by histologic analysis. Statistically significant differences between +bFGF and -bFGF plugs were apparent at d 7 in both plug size and contrast enhancement (both p < 0.05). Histopathology revealed differences in microvessel density (MVD) between +bFGF and -bFGF at d 7 and d 14. A significant correlation between MVD and both power Doppler contrast-enhanced area (r = 0.65, p < 0.05) and fraction of plug enhanced (r = 0.59, p < 0.05) was present. CUI of Matrigel plugs was shown to be a robust method for distinguishing between two different angiogenic states. Ultrasound measurements of blood flow in the plugs correlated with MVD, a histologic technique used to quantify tumor angiogenesis.
Light rail use is more likely on “walkable” blocks: Further support for using micro-level environmental audit measures

The primary purpose of the study was to address the claim that people are more likely to walk to a transit stop if they live on a "walkable" block. An additional purpose was to evaluate the Irvine Minnesota Inventory (IMI) as an environmental audit tool. The IMI was used to measure walkability features of 19 blocks in a revitalizing neighborhood. We hypothesized that residents who walked to a light rail TRAX stop (n = 22) would live on blocks with higher walkability ratings compared to residents who did not walk to TRAX (nonriders, n = 15), or who walked only after a closer TRAX stop was built (new users, n = 11). A MANCOVA indicated the IMI scales differentiated the blocks; the strongest differences were obtained in subscales that measured the block's diversity, safety from crime and density (marginally significant). Participants' perceptions of their complete walk to the transit stop were consistent with the home block IMI scores, with the continuing riders having more positive views than the other two groups. The results show the ability of the IMI to distinguish among blocks in walkability, and support further use of this audit tool in environmental analyses and active living research. We end with a discussion of conceptual and methodological issues in the use of audit tools and provide recommendations for using these measures for local, immediate interests, as well as for building a broader science of environmental measurement.
On requiring the durable goods monopolist to sell

Abstract Requiring a monopolist to sell its output (rather than renting it) my lead to beneficial output adjustments or harmful quality adjustments. In a durable goods model, we show that requiring sales decreases welfare in only a small fraction of cases, but it strictly increases welfare in a majority of cases.