cssi/SciSciGPT-SciSciNet huggingface dataset:
Explicit invariance of Cartesian Zernike moments

Zernike moments are one of the most commonly implemented feature extractors among the family of moment invariants. Their popularity stems from the fact that they are robust in the presence of noise. Their rotational invariance property is inherited from the angular dependence of Zernike polynomials; however the scale and translation invariance cannot be explicitly achieved. One of the indirect approaches to achieve scale and translation invariance is through expressing Zernike moments using centralized and normalized regular moments. In this paper Zernike moments are expressed in Cartesian coordinates to explicitly make them invariant to scale, translation and rotation directly without the need to use the regular moments. These Cartesian Zernike moment invariants are extensively tested using several gray level images. The results clearly demonstrate the effectiveness of the Cartesian Zernike moment invariants and superiority over the indirect approach of expressing Zernike moments using the regular moments.
Darwin's enduring legacy

As the 200th year since the great naturalist's birth begins, Kevin Padian looks forward to a season of celebration by outlining how Darwin's ideas changed scientific thinking.
Cross‐sectional evidence of suppressed bone mineral accrual among female adolescent runners

We aimed to evaluate patterns of bone mineral accrual among a cross-sectional sample of female adolescent runners and girls participating in a nonendurance running sport. One-hundred and eighty-three interscholastic competitive female athletes (age 16.0 +/- 0.1 years), 93 endurance runners and 90 nonrunners, completed a menstrual and sports history questionnaire, had their height and weight measured, and underwent a dual-energy X-ray absorptiometry scan for the measurements of body composition and bone mass. For the majority of analyses, the girls were separated into four groups according to their age (13 to 14 years, 15 years, 16 years, and 17 to 18 years). Runners' height, weight, body mass index (BMI), percent body fat, lean tissue mass, number of menstrual cycles in the past year, and months of participation in a non-lean-build/variable-impact-loading sport were significantly lower than mean values for nonrunners. Although bone mass rose at all sites in the nonrunners between the ages of 13 to 14 years and 17 to 18 years, no such increase was noted in the runners. Runners compared with nonrunners exhibited significantly lower body weight and height-adjusted total body and lumbar spine bone mineral content (BMC) values and lower bone mineral density (BMD) Z-score values among the older (16 years and/or 17 to 18 years) but not younger (13 to 14 years and/or 15 years) age groups. These findings suggest that the runners, in contrast to the nonrunners, exhibited a suppressed bone mineral accrual pattern, which supports the notion that female adolescent endurance runners may be at risk for inadequate bone mass gains and thus a low peak BMD.
A Fluoride with Pyrochlore Structure

THE formula of the rare mineral ralstonite is usually written (Na2,Mg)F2.3Al(F,OH)3.2H2O. This implies a replacement of Na2 by Mg. X-ray investigation of this mineral shows that it belongs to the space-group Oh7 — Fd3m and that the edge of the unit cube has a length of 9.87 A. By recalculation from the best available analysis (Penfield and Harper, 1886), it can be shown that a unit cube contains on the average 48 (F,OH), 16 (Al,Mg), 2.7 Na and 7 H2O. The structure is similar to that of the pyrochlore group (type E 81) for which the formula X2Z2(O,OH,F)7 has been written. In the case of ralstonite the X position (16c) is only partly filled by 2.7 Na. Water partly fills the 8b position which is occupied by O, OH or F in minerals of the pyrochlore group.
Aggressive amyloidosis in mice expressing human amyloid peptides with the Arctic mutation.

The Arctic mutation within the amyloid-β (Aβ) peptide causes Alzheimer disease. In vitro, Arctic-mutant Aβ forms (proto)fibrils more effectively than wild-type Aβ. We generated transgenic mouse lines expressing Arctic-mutant human amyloid precursor proteins (hAPP). Amyloid plaques formed faster and were more extensive in Arctic mice than in hAPP mice expressing wild-type Aβ, even though Arctic mice had lower Aβ1-42/1-40 ratios. Thus, the Arctic mutation is highly amyloidogenic in vivo.
Regional distribution of type 2 thyroxine deiodinase messenger ribonucleic acid in rat hypothalamus and pituitary and its regulation by thyroid hormone

To identify the specific locations of type 2 deiodinase (D2) messenger RNA (mRNA) in the hypothalamus and pituitary gland and determine its regulation by thyroid hormone, we performed in situ hybridization histochemistry, Northern analysis, and quantitative RT-PCR in euthyroid, hypothyroid, and hyperthyroid rats. By in situ hybridization histochemistry, silver grains were concentrated over ependymal cells lining the floor and infralateral walls of the third ventricle extending from the rostral tip of the median eminence (ME) to the infundibular recess, surrounding blood vessels in the arcuate nucleus (ARC), and in the ME adjacent to the portal vessels and overlying the tuberoinfundibular sulci. Silver grains also accumulated over distinct cells in the midportion of the anterior pituitary. In hypothyroid animals, an increase in signal intensity was observed in the caudal hypothalamus, and a marked increase in the number of positive cells occurred in the anterior pituitary. Microdissection of the hypothalam...
Material damping in aluminum and metal matrix composites

The material damping in beam-like specimens of aluminum and metal matrix composites was measured. A unique apparatus to determine damping by free decay while the specimens are in free fall in a vacuum was used. The specimens tested include 2024-T3 and 6061-T4 aluminum, and unidirectional graphite/metal matrix specimens with P55 and P100 fibers and 6061 Aluminum and AZ91C Magnesium as matrix materials. Tests were conducted to determine the dependence of damping on frequency and stress level. For the aluminum specimens, the material damping followed the Zener model at very low stress levels. Below the Zener relaxation frequency, a strong dependence of damping on stress was found for even moderate stress levels. Damping for the aluminum matrix materials was slightly above that predicted by the Zener model for a homogeneous bar of the matrix aluminum. For the magnesium matrix specimens, damping significantly above the Zener prediction for the homogeneous matrix material was observed.
Relation of syncope in young patients with Wolff-Parkinson-White syndrome to rapid ventricular response during atrial fibrillation

Syncope in patients due to Wolff-Parkinson-White (WPW) syndrome may be related either to a rapid rate of supraventricular tachycardia or to rapid ventricular response over the accessory pathway during atrial fibrillation (AF). From 1982 to 1987, 74 patients less than or equal to 25 years old (mean age 12.6 years) with WPW syndrome on electrocardiogram underwent electrophysiologic study. Of the 74 patients, 14 (19%) had a history of syncope. During electrophysiologic study 9 of 14 patients with syncope had sustained (greater than 5 minutes or requiring termination due to hypotension) AF. Of the remaining 5 patients, 3 had inducible nonsustained AF and 2 had no AF. None of the 60 patients without syncope developed sustained AF; 34 had nonsustained and 26 had no AF. Occurrence of sustained AF had a sensitivity of 64% and specificity of 100% for history of syncope. All patients with syncope and AF (12) had a short RR interval between 2 consecutive preexcited QRS complexes during AF at less than or equal to 220 ms, in contrast to 9 of 34 patients without syncope (p less than 0.001, sensitivity 100%, specificity 74%). No patient with a short RR interval between 2 consecutive preexcited QRS complexes during AF of greater than 220 ms had a history of syncope. Thus, in these young patients with WPW syndrome, occurrence of AF with a rapid ventricular response during electrophysiologic study correlated well with a history of syncope and may be the cause of syncope in most patients. Electrophysiologic study may be helpful in identification of young patients with WPW at risk for syncope.
Boiling heat transfer from a tube to immiscible liquid-liquid mixtures

Abstract Experiments were run at atmospheric pressure with water plus each of Freon-113, Freon-112 and n-hexane. Boiling took place on a horizontal 0.25 in. copper tube, tested at separate locations both in the upper and the lower phase. The two liquids were in a pool and distinctly separate. In most cases the presence of the second liquid caused the heat flux to be greater than for one liquid only. The increase is a function of the boiling point depression, the mode of boiling, the quantity of the added liquid, and whether the added liquid floats or sinks.
Diel changes in the presence and physiological actions of octopamine in the female sex-pheromone glands of heliothine moths

Abstract Recent evidence suggests that the biogenic monoamine octopamine (OA) may be involved in the regulation of female sex-pheromone production in Lepidoptera. A radioenzymatic assay coupled with high performance liquid chromatography revealed the presence of OA in the innervated sex-pheromone gland of the corn earworm moth Helicoverpa (Heliothis) zea . Significantly more OA was found in glands just before the onset of scotophase ( ca 320 fmol/gland), compared to levels at mid-photophase or just after the onset of scotophase ( ca 160 fmol/gland). Exogenous OA had several actions on pheromone production. H. zea virgin females normally do not produce pheromone during the photophase, but highly significant levels of pheromone were induced by injection of OA into intact, day-2 photophase females. Importantly, this effect was absent in older females that showed increased levels of flight and oviposition activity. A second action of OA was revealed in isolated abdomen preparations from day-2 H. virescens females. Exogenous OA stimulated highly significant increases in pheromone production if abdomens were treated at the onset of scotophase, but not if they were treated in photophase. This critical period for OA action in these reduced preparations coincided with the time when peak levels of OA were present in the pheromone gland tissue. OA is therefore sufficient to induce pheromone production, but its actions in these short-lived insects depend on factor such as age and photoperiod. Diel fluctuations in OA levels in the pheromone gland, together with the observed phermonotropic actions of this amine, support the hypothesis that OA is involved in the regulation of pheromone production in these insects.
Radio Wave Generation by Multistream Charge Interaction

The excitation of plasma oscillations in traveling beams is reviewed; analytic and graphical methods are employed to ascertain the ranges of parameters over which wave growth may exist and to determine contours of constant amplification factor. The effect of thermal velocities is taken into account by utilizing approximations to a maxwellian distribution. It is found that the possibility of growth exists even for beam injection velocities much smaller than the mean thermal motion in the region; narrow band widths are encountered under these circumstances. Possible applications to solar phenomena are indicated.An investigation of the effect of the initiating disturbance upon the frequency band generated leads to the conclusion that where the possibility of growth in time exists, a spatial description of initial conditions gives rise to a broader band than does a temporal prescription. This is illustrated in specific cases.Previously suggested mechanisms for the conversion of these longitudinal oscillations into transverse electromagnetic energy are considered quantitatively and found to be inadequate. A more promising mechanism is suggested.
A distributed database design for a communications network control system

A three-level distributed database concept is proposed to meet the high performance requirements of an integrated communications network control system. The three levels are source, user, and control. By using fully replicated subject databases in the source level, one regional operations center can serve as a backup for any other center. The applications database in each user level is a subset of the subject databases residing in the source level. Hence, the user level is localized and can respond to near real-time network control requirements. The control level coordinates updates to the distributed database copies. Interactions among the three levels are discussed and four operational stages are considered: initialization, continuous update, global synchronization, and data recovery. A broader usage of the data dictionary is proposed. Simplification of the replicated database design in terms of isolation of global and local data and some implementation considerations are provided.
Thermoelectric power in silver-gold and silver-germanium alloys

Silver-gold and silver-germanium alloys tested for Fermi surface changes with alloying, using thermoelectric power measurements
Image registration by local approximation methods

Abstract Image registration is approached as an approximation problem. Two locally sensitive transformation functions are proposed for image registration. These transformation functions are obtained by the weighted least-squares method and the local weighted mean method. The former is a global method and uses information about all control points to establish correspondence between local areas in the images; nearby control points are, however, given higher weights to make the process locally sensitive. The latter is a local method and uses information about local control points only to register local areas in the images.
Commonality among rats in production of reward and nonreward odors

Male and female test rats acquired a patterned response (fast on reward trials, slow on frustrative nonreward trials) in a runway based on differential odors excreted by donor rats during prior rewarded and nonrewarded placements in the goalbox. Initially, donor-test rat pairs were identical: A randomly selected, same-sex donor preceded the same test subject on each trial. In subsequent phases of the study, donors were interchanged for test rats, both within and between gender categories. Response patterning changed negligibly when the donor-test pairs were altered, suggesting a high degree of commonality among rats in odor excretions following reward and frustrative nonreward treatments.
Magnetohydrodynamic power systems

Liquid-metal and plasma MHD systems for power generation in space environments, noting Rankine and Brayton cycles
Lentiviral transduction of P140K MGMT into human CD34(+) hematopoietic progenitors at low multiplicity of infection confers significant resistance to BG/BCNU and allows selection in vitro.

Lentiviral vectors may improve hematopoietic stem cell (HSC) gene transfer because of their enhanced ability to transduce nondividing cells. However, many studies report efficient transduction only at high multiplicities of infection (MOI). This study reports efficient transduction of human CD34+ cells with a drug resistance gene allowing post-transduction selection using lentivirus under low-MOI conditions that did not require cytokine stimulation or viral concentration. We used the P140K methylguanine-DNA-methyltransferase mutant (P140K MGMT) as the gene insert into a second-generation lentiviral backbone and triple-plasmid transfection to generate vesicular stomatitis virus (VSV)-G protein-pseudotyped virus. The P140K MGMT gene product, O6-alkylguanine-DNA-alkyltransferase (AGT), provides protection from the therapeutic drug combination of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and the wild-type AGT inhibitor O6-benzylguanine (BG). Low-speed spinoculation enhanced transduction more than addition of Polybrene or multiple virus exposures. Addition of cytokines was not required. Low-MOI transduction (≤1) of human CD34+ and CD34+ lin− cells with P140K MGMT lentivirus resulted in an average 41% and 89% gene transfer rate as assessed by PCR, respectively, and concordant AGT expression that conferred substantial clonogenic survival advantage after BG/BCNU treatment. During in vitro drug selection, 87% of surviving CD34+ cell-derived colony-forming units (CFU) were transduced. This work shows the potential utility of lentiviral vectors for drug resistance gene transfer to HSCs for the purpose of in vivo selection and marrow protection. Because drug selection will enrich for transduced progenitors, high MOI can be avoided, improving the safety profile of lentiviral gene transfer.
On component analyses

Principal components analysis can be redefined in terms of the regression of observed variables upon component variables. Two criteria for the adequacy of a component representation in this context are developed and are shown to lead to different component solutions. Both criteria are generalized to allow weighting, the choice of weights determining the scale invariance properties of the resulting solution. A theorem is presented giving necessary and sufficient conditions for equivalent component solutions under different choices of weighting. Applications of the theorem are discussed that involve the components analysis of linearly derived variables and of external variables.
Implication Algebras and the Metropolis - Rota Axioms for Cubic Lattices

Abstract This paper is motivated by a result of Metropolis and Rota on an algebraic characterization of the lattice of faces of the n-cube (cubic lattice). Although their proof relies on an inductive argument, the axioms are independent of the dimension n. The question of how to extend this theory to include infinite cubic lattices was left open. We develop an extended characterization theory of cubic lattices of arbitrary dimension by adding three axioms (completeness, atomicity, and coatomicity) to those of Metropolis and Rota. The proof of our main theorem depends on the introduction of the cubic implication algebra, which is shown to satisfy Abbott′s axioms for implication algebras. These algebras were first developed to characterize semi-Boolean algebras and Boolean algebras.
On optimization of the powder plasma arc surfacing process

METALLURGICAL AND MATERIALS TRANSACTIONS B In summary, a re-examination of the influence of the gascarbon reaction on the reaction kinetics of FeO by solid carbon using recently available data has shown that this reaction may have a significant effect on the observed rates. A comprehensive mixed control model was used to evaluate the influence of the gas-carbon reaction on the observed reduction rate, and the predictions agree well with the measured data. In general, the overall rate is controlled by the various steps in a series. The predominant step will depend on the stirring condition and type of carbon. The rates observed in graphite are probably not strongly affected by the gas-carbon reaction, the rate limiting steps are liquid phase mass transfer in combination with the slag-gas reaction. On the other hand, when coke is used, the considerably lower reactivity of this carbonaceous material to CO2 at high temperatures appears to cause this reaction to have significant influence on the rate of reduction.
Bimodal tholeiitic—dacitic magmatism and the Early Precambrian crust

Abstract Interlayered plagioclase-quartz gneisses and amphibolites from 2.7 to more than 3.6 b.y. old form much of the basement underlying Precambrian greenstone belts of the world; they are especially well-developed and preserved in the Transvaal and Rhodesian cratons. We postulate that these basement rocks are largely a metamorphosed, volcanic, bimodal suite of tholeiite and high-silica low-potash dacite—compositionally similar to the 1.8-b.y.-old Twilight Gneiss — and partly intrusive equivalents injected into the lower parts of such volcanic piles. We speculate that magmatism in the Early Precambrian involved higher heat flow and more hydrous conditions than in the Phanerozoic. Specifically, we suggest that the early degassing of the Earth produced a basaltic crust and pyrolitic upper mantle that contained much amphibole, serpentine, and other hydrous minerals. Dehydration of the lower parts of a downgoing slab of such hydrous crust and upper mantle would release sufficient water to prohibit formation of andesitic liquid in the upper part of the slab. Instead, a dacitic liquid and a residuum of amphibole and other silica-poor phases would form, according to Green and Ringwood's experimental results. Higher temperatures farther down the slab would cause total melting of basalt and generation of the tholeiitic member of the suite. This type of magma generation and volcanism persisted until the early hydrous lithosphere was consumed. An implication of this hypothesis is that about half the present volume of the oceans formed before about 2.6 b.y. ago.
On the mechanical stability of bcc transition elements and alloys

Abstract A volume independent and a volume dependent lattice energy function involving short-range interatomic potentials were able to be fitted to the elastic constants, cohesive energy, lattice parameter and for the latter function to the vacancy formation energy and bcc-fcc lattice stability energy, as well, for fcc metals and bcc alkali metals, but not to the cohesive energy and C ' elastic constant of bcc transition metals. The assumption that directional, but partial, covalent bonds exist between nearest-neighbors in the bcc transition elements provides an explanation for the latter results and in addition explains the identical dependence of C ' and the bcc-fcc lattice stability upon N d , where N d is the average number of d electrons, for the bcc transition metals and alloys. Both the mechanical and thermodynamic stability of the bcc structure for transition metals and all transition metal alloys disappears for 5 − N d > 2 and
Effects of hydration in rats and mice with polycystic kidney disease.

Vasopressin and V2 receptor signaling promote polycystic kidney disease (PKD) progression, raising the question whether suppression of vasopressin release through enhanced hydration can delay disea...
Working With Tensions Materiality, Discourse, and (Dis)empowerment in Occupational Identity Negotiation Among Higher Education Fund-Raisers

The increasing time requirements and perceived value of occupations raises concerns about creating and managing positive occupational identities. The author explains how individuals pursue moments ...
Catalytic Processing of Lactic Acid over Pt/Nb2O5

Dilute aqueous solutions of lactic acid (30 %wt.) can be catalytically processed at 573 K and 57 bar over a low-metal-content Pt(0.1 %)/Nb(2)O(5) catalyst in a spontaneously separating organic phase rich in valuable products such as C(4)-C(7) ketones. An increase in the lactic acid concentration to 60 wt % allows conversion of approximately 50 % of the carbon feed in this organic layer, while maintaining good stability of the catalyst. Experiments at low conversion showed that lactic acid reacts first over Pt(0.1 %)/Nb(2)O(5) to produce acetaldehyde and propanoic acid (along with CO and CO(2) in the gas phase). These compounds (less oxygenated than lactic acid but still reactive) are the key intermediates in the overall process, and they react differently depending on the nature of the catalyst support. In particular, reaction kinetics studies with propanoic acid as feed showed that Pt(0.1 %)/Nb(2)O(5) favored the formation of pentanones by ketonization reactions, whereas a monofunctional Pt(0.1 %)/carbon catalyst produced ethane and CO(x) by decomposition reactions. In the same manner, acetaldehyde was preferentially hydrogenated to ethanol over Pt(0.1 %)/carbon, whereas the presence of niobia allowed this intermediate to react (by successive aldol condensations) to form C(4)-C(7) condensation products stored in the organic phase. Finally, reaction pathways are proposed to explain the catalytic processing of lactic acid over bifunctional Pt(0.1 %)/Nb(2)O(5). In this scheme, metal sites catalyze hydrogenation reactions and niobia promotes C--C coupling processes (ketonization and aldol condensation), in contrast to C--C cleavage reactions which take place preferentially over Pt(0.1 %)/carbon and lead to loss of carbon in the gas effluent as CO, CO(2), and methane.
High-performance FPGA-based general reduction methods

FPGA-based floating-point kernels must exploit algorithmic parallelism and use deeply pipelined cores to gain a performance advantage over general-purpose processors. Inability to hide the latency of lengthy pipelines can significantly reduce the performance or impose unrealistic buffer requirements. Designs requiring reduction operations such as accumulation are particularly susceptible. In this paper we introduce two high-performance FPGA-based methods for reducing multiple sets of sequentially delivered floating-point values in optimal time without stalling the pipeline.
The epidemiology of the postpericardiotomy syndrome: A common complication of cardiac surgery☆

PPS is a major cause of morbidity after cardiac surgery and may cause bypass graft closure and fatal cardiac tamponade. Little is known about its incidence and cause. To better define this syndrome characterized by postoperative fever, pericardial friction rub, and pericardial pain, we used two out of three of the preceding criteria to diagnose PPS. In a prospective epidemiologic study we followed 944 consecutive patients undergoing open-heart surgery between November 1984 and November 1985. The overall incidence was 17.8%. The incidence was increased in younger patients, in those with a history of prednisone use in the past, in patients with a past history of pericarditis, those with aortic valve replacement, and in patients who received enflurane or halothane anesthesia. PPS is a common syndrome. Knowledge of risk factors associated with PPS may allow its prevention and identification of patients who warrant early and aggressive treatment.
TRENDS IN BREAST CANCER BY RACE AND ETHNICITY

In this article, the American Cancer Society (ACS) describes trends in incidence, mortality, and survival rates of female breast cancer in the United States by race and ethnicity. It also provides estimates of new cases and deaths and shows trends in screening mammography. The incidence and survival data derive from the National Cancer Institute's Surveillance, Epidemiology, and End Results program; mortality data are from the National Center for Health Statistics. Approximately 211,300 new cases of invasive breast cancer, 55,700 in situ cases, and 39,800 deaths are expected to occur among women in the United States in 2003. Breast cancer incidence rates have increased among women of all races combined and white women since the early 1980s. The increasing rate in white women predominantly involves small (< or = 2 cm) and localized-stage tumors, although a small increase in the incidence of regional-stage tumors and those larger than five cm occurred since the early 1990s. The incidence rate among African American women stabilized during the 1990s for all breast cancers and for localized tumors. African American women are more likely than white women to be diagnosed with large tumors and distant-stage disease. Other racial and ethnic groups have lower incidence rates than do either white or African American women. However, the proportion of disease diagnosed at advanced stage and with larger tumor size in all minorities is greater than in white persons. Death rates decreased by 2.5% per year among white women since 1990 and by 1% per year among African American women since 1991. The disparity in mortality rates between white and African American women increased progressively between 1980 and 2000, so that by 2000 the age-standardized death rate was 32% higher in African Americans. Clinicians should be aware that 63% and 29% of breast cancers are diagnosed at local- and regional-stage disease, for which the five-year relative survival rates are 97% and 79%, respectively. This information, coupled with decreasing mortality rates and improvements in treatment, may motivate women to have regular mammographic and clinical breast examinations. Continued efforts are needed to increase the availability of high-quality mammography and treatment to all segments of the population.
Dietary Recommendations During and After Cancer Treatment: Consistently Inconsistent?

Recent data reveals that dietary factors may influence outcomes in patients undergoing cancer treatment. However, patient-centered information on dietary recommendations is limited. In this study, we assessed dietary recommendations for cancer patients during treatment and survivorship by evaluating the websites of all National Comprehensive Cancer Network (NCCN) member institutions. NCCN members were identified on www.nccn.org, and individual websites were reviewed for nutritional content. Recommendations were categorized by meal frequency, diet type, macronutrient content, and other specific recommendations. Twenty-one NCCN member institutions were identified. Only 4 sites (19%) provided nutritional guidelines. Half promoted a low-fat, high-carbohydrate diet recommending 5:1 and 7:1 ratios of carbohydrate to fat food types, and half promoted weight maintenance during treatment, endorsing a 1:1 ratio of carbohydrate to fat. One third of all NCCN sites (n = 7) had links to 9 external websites. Four extern...
The Importance of Boundary Conditions in Solving the Bound-State Bethe-Salpeter Equation

The characteristic of bound-state, Bethe-Salpeter equations that makes them so difficult to solve numerically can be overcome, in some if not many cases, by expanding solutions in terms of basis functions that obey the boundary conditions that are satisfied by the solutions. The utility of such basis functions is demonstrated by calculating the zero-energy, bound-state solutions of a spin-0 boson and a spin-½ fermion with unequal masses. The constituents interact via scalar electrodynamics and are described by the Bethe-Salpeter equation in the ladder approximation. Although the Bethe-Salpeter equation that is solved is separable in the zero-energy limit, the feature that typically prevents solutions from being obtained numerically is still present. A technique for calculating boundary conditions, which is readily generalized to other Bethe-Salpeter equations, is discussed in detail.
Temporal Low-Order Statistics of Natural Sounds

In order to process incoming sounds efficiently, it is advantageous for the auditory system to be adapted to the statistical structure of natural auditory scenes. As a first step in investigating the relation between the system and its inputs, we study low-order statistical properties in several sound ensembles using a filter bank analysis. Focusing on the amplitude and phase in different frequency bands, we find simple parametric descriptions for their distribution and power spectrum that are valid for very different types of sounds. In particular, the amplitude distribution has an exponential tail and its power spectrum exhibits a modified power-law behavior, which is manifested by self-similarity and long-range temporal correlations. Furthermore, the statistics for different bands within a given ensemble are virtually identical, suggesting translation invariance along the cochlear axis. These results show that natural sounds are highly redundant, and have possible implications to the neural code used by the auditory system.
A laboratory study to evaluate the toxicity of the Mediterranean fruit fly, Ceratitis capitata, bait, Success 0.02 CB, to the honey bee, Apis mellifera

USDA APHIS and Moscamed have developed an eradication program for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in North and Central America. Currently, the primary chemical used to control fruit flies in Central America is spinosad, Success 0.02 CB™ (GF-120). Central America, and Guatemala in particular, has a thriving apiculture industry. Many Guatemalan beekeepers believe that Success is toxic to honey bees, Apis mellifera L., and that its use has resulted in a decrease in bee populations and subsequent honey production. Continuous, limited, and topical exposure studies demonstrated that Success is toxic to honey bees at varying levels, depending upon exposure and drying time, as demonstrated by 24 h bioassays. Future studies should evaluate the effects of Success in the field on foraging honey bees and brood health during a season long Medfly control program to determine possible honeybee impacts. Apis mellifera / Ceratitis capitata / spinosad / Success 0.02 CB / toxicity / apiculture
Finding possible transition states of defects in silicon-carbide and alpha-iron using the dimer method

Energetic primary recoil atoms from ion implantation or fast neutron irradiation produce isolated point defects and clusters of both vacancies and interstitials. The migration energies and mechanisms for these defects are crucial to successful multiscale modeling of microstructural evolution during ion-implantation, thermal annealing, or under irradiation over long periods of time. The dimer method is employed to search for possible transition states of interstitials and small interstitial clusters in SiC and a-Fe. The method uses only the first derivatives of the potential energy to find saddle points without knowledge of the final state of the transition. In SiC, the possible migration pathway for the C interstitial is found to consist of the first neighbor jump via a Si site or second neighbor jump, but the relative probability for the second neighbor jump is very low. In a-Fe, the possible transition states are studied as a function of interstitial cluster size, and the lowest energy barriers correspond to defect migration along h 111 i directions. However, this paper addresses whether migrating interstitial clusters can thermally change their direction, and the activation energies and corresponding mechanisms for changing the direction of these clusters are determined. 2002 Elsevier Science B.V. All rights reserved.
The HWE Histidine Kinases, a New Family of Bacterial Two-Component Sensor Kinases with Potentially Diverse Roles in Environmental Signaling

Two-component signal transduction pathways play a major role in the response of bacteria to external cues. These pathways are initiated by large collection of histidine kinases (HKs) containing a sensor domain that perceives the environmental signal followed by an HK domain that triggers a histidine-aspartate phosphorelay. Previous phylogenetic analyses identified 11 major families of two-component HKs by comparing signature motifs within the HK domain. Here we describe a new family with homology to Agrobacterium tumefaciens BphP2, an HK first discovered by the presence of a phytochrome sensor domain involved in light perception. Members of this sensor HK family differ from most others by the absence of a recognizable F box and the presence of several uniquely conserved residues, including a histidine in the N box and a tryptophan-X-glutamic acid sequence in the G1 box, which we have used to define the family (HWE). At least 81 members were identified in a variety of α- and γ-proteobacteria, with a significant enrichment in the Rhizobiaceae family. Several representatives were shown to have HK activity in vitro, supporting their proposed participation in phosphorelays. One or more domains related to signal transduction were evident N-terminal to the HK domain, including chemotactic methyltransferase domains, suggesting that this family has multiple roles in environmental signaling. The discovery of the HWE family further extends the diversity within the HK superfamily and expands the importance of two-component signaling in bacteria.
Is It Ethical for Patents to Be Issued for the Computer Algorithms That Affect Course Management Systems for Distance Learning

Abstract This article discusses the impact of patents for computer algorithms in course management systems. Referring to historical documents and court cases, the positive and negative aspects of software patents are presented. The key argument is the accessibility to algorithms comprising a course management software program such as Blackboard. The algorithms claimed in the Blackboard patent are critical to the development of distance learning. The impact of patenting these algorithms in the field of online education is evaluated using three ethical frameworks. As education moves online, it is important that distance learning be allowed to develop freely unencumbered by software patents.
A unit selection approach to F0 modeling and its application to emphasis

The paper presents a new unit selection approach to F0 modeling for speech synthesis. We construct the F0 contour of an utterance by selecting portions of contours from a recorded speech database. In this approach, the elementary unit is the segment, which gives the system flexibility to combine segments from different phrases and model both macroprosody and microprosody. Using this method, we built a model of emphasis in English. Informal experimental results show that utterances whose prosody was generated with our method are generally preferred over utterances using Festival's handwritten rule-based F0 model.
Effects of Soil Chemistry on Plant Germination and Growth in a Northern Everglades Peatland

Vegetation patterns across the Florida Everglades peatland are influenced by anthropogenic gradients in both hydrology and chemistry. These gradients often overlap, making it difficult to isolate specific causes of vegetation change. We examined whether differences in plant communities between the minimally impacted interior and the impacted perimeter of the northern Everglades could be attributed to soil chemistry as opposed to other factors such as hydrology or seed-bank composition. Seedling establishment from soil seed banks collected from interior locations was examined under conditions that reflected either the phosphorus (P)- and calcium-carbonate (CaCO3)-depleted chemistry of the peatland interior or enriched conditions around the perimeter. Three soil moisture treatments were used to increase seed-bank expression. The interior seed bank contained viable seeds of both interior and perimeter taxa, but distinct plant assemblages established in the two chemistry treatments. Perimeter species germinated in both chemistry treatments, but only survived under enriched conditions. Establishment of these species in the interior is likely limited by low P availability. Germination and survival of some interior species were reduced by enrichment, likely due to elevated CaCO3 levels. Protection from both increased P and CaCO3 loads thus appears important to maintain plant communities in mineral-poor remnants of the Everglades.
Quality of in-home care, long-term care placement, and the survival of persons with dementia.

Purpose of the study: Caregivers of persons with dementia living at home adopt a variety of caregiving styles that vary in quality. Three styles of high-quality care and poor-quality care have been identified. The outcomes, however, of varying styles of caregiving are unknown. Our purpose was to investigate the linkage of quality of care to long-term care placement and survival.Design and methods: We used a sample of 148 primary caregivers of a relative living at home and needing assistance due to memory or thinking problems. We used items from four existing scales and five new items to construct measures of high-quality and poor-quality care. Long-term care and survival were determined from two follow-ups. Cox proportional hazards regression was used to estimate the relationship of quality of care to long-term care placement and survival.Results: Poor quality of care increased the risk of long-term care placement, as expected, but high-quality care was not related to placement. Surprisingly, high-quality...
Automated prediction of domain boundaries in CASP6 targets using Ginzu and RosettaDOM

Domain boundary prediction is an important step in both experimental and computational protein structure characterization. We have developed two fully automated domain parsing methods: the first, Ginzu, which we have described previously, utilizes information from homologous sequences and structures, while the second, RosettaDOM, which has not been described previously, uses only information in the query sequence. Ginzu iteratively assigns domains by homology to structures and sequence families using successively less confident methods. RosettaDOM uses the Rosetta de novo structure prediction method to build three-dimensional models, and then applies Taylor's structure based domain assignment method to parse the models into domains. Domain boundaries observed repeatedly in the models are predicted to be domain boundaries for the protein. Interestingly, RosettaDOM produced quite good domain predictions for proteins of a size typically considered to be beyond the reach of de novo structure prediction methods. For remote fold recognition targets and new folds, both Ginzu and RosettaDOM produced promising results, and in some cases where one method failed to detect the correct domain boundary, it was correctly identified by the other method. We describe here the successes and failures using both methods, and address the possibility of incorporating both protocols into an improved hybrid method.
Energetics of isometric force development in control and volume-overload human myocardium. Comparison with animal species.

Alteration in crossbridge behavior and myocardial performance have been associated with myosin isoenzyme composition in animal models of myocardial hypertrophy or atrophy. In the hypertrophied human heart, myocardial performance is altered without significant changes in myosin isoenzymes. To better understand this discrepancy, isometric heat and force measurements were carried out in 1) control and volume-overload human myocardium, 2) control, pressure-overload, and hyperthyroid rabbit myocardium, and 3) control and hypothyroid rat myocardium. In control human myocardium, peak isometric twitch tension was 44.0 +/- 11.7 mN/mm2, and maximum rate of tension rise was 69.2 +/- 21.0 mN/sec.mm2. In volume-overload human myocardium, peak twitch tension and maximum rate of tension rise were reduced by 55% (p less than 0.05) and 65% (p less than 0.05), respectively. The average force-time integral of the individual crossbridge cycle, calculated by myothermal techniques, was increased by 85% (p less than 0.005) in volume-overload human myocardium. In control and hormonally altered myocardium, both across and within species (control human, control rat, control rabbit, hypothyroid rat, and hyperthyroid rabbit), there was a close relation between the crossbridge force-time integral and the percentage of V3-type myosin isoenzyme in the myocardium. However, hemodynamically altered (volume-overload human and pressure-overload rabbit) myocardium did not follow this relation. Across and within species, there were significant correlations between maximum rate of tension rise and average tension-dependent heat rate (r = 0.97, p less than 0.001) and between maximum rate of tension fall and average tension-independent heat rate (r = 0.82; p less than 0.025). Furthermore, there were close inverse relations between these heat rates and the crossbridge force-time integral. In addition, there was an inverse relation between tension-independent heat and the crossbridge force-time integral. Across and within species total myocardial energy turnover was significantly correlated with the crossbridge force-time integral (relative total heat, r = -0.84, p less than 0.02; relative total-activity related heat, r = -0.88, p less than 0.01). The present findings indicate that 1) factors separate from myosin isoenzymes account for the altered crossbridge cycle in volume-overload human and pressure-overload rabbit myocardium, 2) changes in excitation-contraction coupling processes accompany changes in the crossbridge cycle within and across species, and 3) the force-time integral of the crossbridge cycle is a major determinant of total myocardial energy turnover.
Nutrition and alcoholism

summary. Nevertheless, this book is not for the casual reader and perhaps is ofmost value to academic scientists in the field and secondarily to thoughtful practitioners of medicine. Perhaps generic to an extensive and time-consuming publishing enterprise, the material appears to summarize progress in papers published up until 1991, unfortunately minimizing much new and relevant data in such areas as the potential role of nutrient antioxidants, cytokines, and eicosanoids in liver disease; alcohol-induced nutrient deficiencies related to carcinogenesis; a growing body of information on the value of nutritional support in decompensating liver disease; and the potential role of nonalcoholic components of alcoholic bev­ erages in the prevention of coronary artery disease. With the fo­ cus on the basic pathogenesis of alcoholism and its syndromes, the book provides operational guidelines but few detailed ap­ proaches to management. Because the emphasis is on alcoholism as a disease, little attention is paid to potential interactions of moderate consumption of alcohol as a constituent of the diet, providing on average 5% of dietary energy of the American pop­ ulation. For instance, one would like to know how moderate as
A Comparison of the Energetics of Proton Transfer in the Serine and Cysteine “Charge Relay” Systems and the Role of the Protein Electrostatic Potential on the Proton Transfer Energetics

We present ab initio calculations on models of the “charge relay” triads Serine-Histidine-Aspartate, Cysteine-Histidine-Asparagine and Cysteine-Histidine-Aspartate. The direct calculations on double proton transfer indicate that it is significantly more favourable than single proton transfer in both serine and cysteine protease models and Asp is considerably more effective than Asn as the third member of the triad. However, correcting these proton transfer energies for known deficiencies in calculated proton affinities makes single proton transfer more likely than double proton transfer. The electrostatic potential in a-chymotrypsin makes the proton transfer more difficult, whereas that in subtilisin facilitates it. In papain, the potential favours single proton transfer, but not double proton-transfer.