cssi/SciSciGPT-SciSciNet huggingface dataset:
Emigration Effects on Estimates of Age- and Sex-specific Survival of Small Mammals

O_LIAge- and sex-specific survival estimates are crucial to understanding important life-history characteristics and variation in these estimates can be a key driver of population dynamics. When estimating survival using Cormack-Jolly-Seber (CJS) models and capture-recapture data, emigration is typically assumed to have a negligible effect on estimates such that apparent survival is indistinguishable from true survival. Consequently, especially for populations or age classes with high dispersal rates, apparent survival estimates are often biased low and temporal patterns in survival might be masked when site fidelity varies temporally. C_LIO_LIWe used 9 years of annual mark-recapture data to estimate age-, sex-, and time-specific apparent survival of Humboldts flying squirrels (Glaucomys oregonensis) and Townsends chipmunks (Neotamias townsendii). For Humboldts flying squirrels, these estimates support a small body of research investigating potential variation of survival among age and sex classes, but age- and sex-specific survival has not been evaluated for Townsends chipmunks. We also quantified the effects of age- and sex-specific emigration on confounded estimates of apparent survival. C_LIO_LIOur estimates of juvenile flying squirrel survival were high relative to other small mammal species and estimates for both species were variable among years. We found survival differed moderately among age and sex classes for Humboldts flying squirrels, but little among age and sex classes for Townsends chipmunks, and that the degree to which emigration confounded apparent survival estimates varied substantially among years. Without correcting for emigration, apparent survival estimates were lower and temporal variation was obscured, particularly for male Humboldts flying squirrels and female Townsends chipmunks. C_LIO_LIOur results demonstrate that emigration can influence commonly used estimates of apparent survival. Unadjusted estimates confounded the interpretation of differences in survival between age and sex classes and masked potential temporal patterns in survival because the magnitude of adjustment varied among years. We conclude that apparent survival estimators are robust during some time periods; however, when emigration rates vary in time the effects of emigration should be carefully considered and accounted for, especially in comparative studies and those with policy and conservation implications. C_LI
Ancestry of cells must be considered in bioengineering

Bioengineered platforms, intended to be used in the investigation of human health and disease, often incorporate cells of unknown ancestry or that lack diversity. To develop tools and platforms that benefit the entire human population, we must consider the ancestry of cells and intentionally diversify the cells we use in our designs.
Endogenous giant viruses shape intraspecies genomic variability in the model green alga Chlamydomonas reinhardtii

Chlamydomonas reinhardtii is an important eukaryotic alga that has been studied as a model organism for decades. Despite extensive history as a model system, phylogenetic and genetic characteristics of viruses infecting this alga have remained elusive. We analyzed high-throughput genome sequence data of numerous C. reinhardtii isolates, and in six strains we discovered endogenous genomes of giant viruses reaching over several hundred kilobases in length. In addition, we have also discovered the entire genome of a closely related giant virus that is endogenized within the genome of Chlamydomonas incerta, one of the closest sequenced phylogenetic relatives of C. reinhardtii. Endogenous giant viruses add hundreds of new gene families to the host strains, highlighting their contribution to the pangenome dynamics and inter-strain genomic variability of C. reinhardtii. Our findings suggest that endogenization of giant viruses can have profound implications in shaping the population dynamics and ecology of protists in the environment.
Inhibition of Gap-Junctional Communication Induces the Trans-differentiation of Osteoblasts to an Adipocytic Phenotype in Vitro

Osteoblasts and adipocytes are thought to differentiate from a common stromal progenitor cell. These two phenotypically mature cell types show a high degree of plasticity, which can be observed when cells are grown under specific culture conditions. Gap junctions are abundant among osteoblastic cellsin vivo and in vitro, whereas they are down-regulated during adipogenesis. Gap junctional communication (GJC) modulates the expression of genes associated with the mature osteoblastic phenotype. Inhibition of GJC utilizing 18-α-glycyrrhetinic acid (AGRA) blocks the maturation of pre-osteoblastic cells in vitro. Moreover, cytoplasmic lipid droplets are detectable at the end of the culture period, suggesting that GJC inhibition may favor an adipocytic phenotype. We used several human osteoblastic cell lines, as well as bone-derived primary osteoblastic cells, to show that confluent cultures of human osteoblastic cells grown under osteogenic conditions developed an adipocytic phenotype after 3 days of complete inhibition of GJC using AGRA or oleamide, two dissimilar nontoxic reversible inhibitors. Development of an adipogenic phenotype was confirmed by the accumulation of triglyceride droplets and the increase in mRNA expression of the adipocytic markers peroxisome proliferator-activated receptor γ2 and lipoprotein lipase. Glycyrrhizic acid, a noninhibitory AGRA analog, or α-bromopalmitate, a nondegradable fatty acid, had no effect. Modulation of skeletal GJC may represent a new pharmacological target by which inhibition of marrow adipogenesis can take place with the parallel enhancement of osteoblastogenesis, thus providing a novel therapeutic approach to the treatment of human age-related osteopenic diseases and postmenopausal osteoporosis.
Biosynthesis of Gossypol INCORPORATION OF MEVALONATE-2-14C AND ISOPRENYL PYROPHOSPHATES

Abstract Based on the previous observations that gossypol is biosynthetically formed from acetate, and from the location of the incorporated 14C atoms, gossypol biosynthesis via the isoprenoid pathway has been postulated. To support this hypothesis, the incorporation of mevalonate-2-14C (a key intermediate in the isoprenoid pathway) into gossypol as well as the distribution of the radioactivity in the gossypol molecule was studied. The results showed that 6 molecules of mevalonate-2-14C are stereospecifically incorporated into 1 molecule of gossypol. The monoterpene alcohols, geraniol-2-14C and nerol-2-14C, were chemically synthesized and the incorporation of their respective pyrophosphate ester into gossypol was tested. The incorporation of geranyl-2-14C pyrophosphate into gossypol was equal to the incorporation of mevalonate-2-14C, whereas neryl-2-14C pyrophosphate was utilized twice as efficiently as mevalonate-2-14C. The location of the 14C atoms of these substrates in the gossypol molecule was consistent with the isoprenoid pathway. Similarly, the cis-cis isomer of the sesquiterpene alcohol, farnesyl-2-14C-PP, was 4 times as efficient as substrate compared to the trans-cis isomer. In constrast, the incorporation of trans-trans- and cis-trans-farnesyl-2-14C-PP into gossypol was negligible. From the labeling pattern of gossypol synthesized from mevalonate-2-14C, neryl-2-14C-PP, and trans-cis-farnesyl-2-14C-PP, it is proposed that gossypol is produced by a specific cyclization of cis-cis-farnesyl pyrophosphate.
A covering lemma for rectangles in ℝⁿ

We prove a covering lemma for rectangles in R which has connections to a problem of Zygmund and its solution in three dimensions by Cordoba.
Pathobiology of acute triethyltin intoxication.

Publisher Summary The rapid induction of triethyltin intoxication during a 24-hour period appears to emphasize the sequential morphological, chemical, and physiological responses of the nervous system, which lead to cerebral edema. In these animals, two distinct episodes of stupor and coma are identified. One occurs shortly after the administration of the organotin, is not present following a dose of 4 mg/kg or less, and does not appear to be related to fluid imbalance. The second episode is slowly progressive and appears to be temporally related to the accumulation of fluid in the brain. The sequential study of altered morphology in the white matter reveals that a period of cell swelling, involving astrocytes and axons, occurs at about the time of earliest increase of fluid in the brain. At this time there is similar involvement of astrocytes in the gray matter, so astrocytes in both the gray and white matter appears to be reacting similarly. In the white matter, this period of cell swelling is limited by the development of myelin clefts. The excess fluid in the white matter appears to accumulate in these clefts, and the cytoplasmic volume of cells in the white matter returns to normal or slightly less than normal.
The Mannich Reaction

The Mannich reaction consists in the condensation of ammonia or a primary or secondary amines, usually as the hydrochloride, with formaldehyde and a compound containing at least one hydrogen atom of pronounced reactivity. The essential feature of the reaction is the replacement of the active hydrogen atom by an aminomethyl or substituted aminomethyl group. The product from acetophenone, formaldehyde, and a secondary amine salt is an example. The product to be expected from a Mannich reaction involving an ammonium salt is a primary amine. The mechanism of the Mannich reaction has not been established. Keywords: Mannich reaction; secondary amines; primary amines; ammonia; ketones; aldehydes; acids; esters; phenol; picolines; acetylenes; quinaldines
"A More Accurate and Extensive Education than is Customary": Educational Opportunities for Women in Early-Nineteenth-Century New Jersey

This article examines the variety of educational opportunities available to New Jersey women in the first half of the nineteenth century. While largely ignored in the national historiography on womenâ€Ÿs education, numerous groundbreaking schools for women were established throughout New Jersey in the early nineteenth century. The Newark Academy offered instruction to women since the late eighteenth century; its successor, the Newark Institute for Young Ladies, referred to its curriculum as “collegiate” decades before women were admitted to colleges. In the 1830s, the Bloomfield Female Seminary maintained a reputation for scholarly excellence; throughout the 1840s, the Mount Holly Female Seminary offered a course of study for women seeking to become teachers. By the 1840s, schools could be found in various cities and towns, including Bloomfield, Bordentown, Burlington, Freehold, Lawrenceville, Newark, New Brunswick, Rahway, and Raritan. The New Jersey schools examined in this essay shed light on both local and national practices of womenâ€Ÿs education. As womenâ€Ÿs access to education expanded, so did debates about the appropriate uses of education. While many men supported womenâ€Ÿs education, women understood that they could be subject to criticism from those who feared the consequences of their intellectual pursuits. Analysis of the forms, purposes, and uses of womenâ€Ÿs education, as evident in these New Jersey case studies, illustrates both the opportunities and challenges that teachers, students, and supporters faced as they sought to expand womenâ€Ÿs institutional access to education
Investigation of CMOS devices with embedded SiGe source/drain on hybrid orientation substrates

CMOS devices with embedded SiGe source/drain for pFETs and tensile stressed liner for nFETs have been demonstrated for the first time on hybrid orientation substrates. Ring oscillators have also been fabricated. Significant performance improvement is observed in hybrid orientation substrates compared to (100) control substrates with embedded SiGe.
Coulomb counting state-of-charge algorithm for electric vehicles with a physics-based temperature dependent battery model

This paper proposes a new Coulomb counting state-of-charge (SOC) algorithm for a lithium iron phosphate battery that achieves accurate results (3.8% standard deviation) for several drive cycles and temperatures between −10°C and 20°C. The basis for this method is a physics-based battery model that compensates for the influences of drive dynamics and temperature on the SOC estimates, instead of the data-driven, empirical adjustments that have been reported in the literature to date. The method also provides compensation for battery aging effects by recursively updating the battery parameters using a Kalman filter algorithm. This method has been evaluated using both lab equipment and a converted Ford F150 electric truck. The results confirm the robustness of the proposed algorithm for suppressing the influences of drive dynamics and temperature on SOC estimates.
Childhood injuries: a challenge to society.

The general public still seems largely unaware of the cost in human lives, health, and happiness of the present toll of accidental injury and death in our society. This applies particularly to death and injury of children. Those people professionally involved in the end results-the physicians and others who see the unnecessary suffering-recognize the extent of the problem, but outside this group even the educated public displays a curious indifference. In a recent book on contemporary social problems, there is no mention of accidental injury and death throughout the whole 600-odd pages. The reasons for this neglect and indifference to a problem whose incidence and consequences could probably be reduced are unclear. Even in the matter of automobile accidents, which kill some 50,000 persons annually in the United States and maim and injure hundreds of thousands of others, there appears to be a fatalistic acceptance which is quite extraordinary when one reflects on it. It is a great pity that all motor car accidents do not happen on the same day; perhaps the shock of seeing American highways reduced to the condition of a battlefield might dramatize the problem sufficiently for steps to be taken about controlling it. The public's acceptance of death on the highway contrasts sharply with its responsiveness to dramas involving very rare diseases or conditions: the polio vaccine deaths of a few years ago, for example, in which, statistically speaking, the danger was infinitesimal. The debate about guncontrol legislation is another case in point. This has been dramatized by the deaths by gunfire of a small number of prominent men within a limited period, but the fact that more than 500 children lose their lives every year as a result of shootings seemed unable to generate an equal display of concern, despite the fact that ours is a society in which the child is supposed to be revered. Language: en
A Descriptive Study of Universities' Use of GRE® General Test Scores in Awarding Fellowships to First‐Year Doctoral Students

The purpose of this study was to investigate the ways in which universities use the GRE® General Test scores to award merit-based fellowships to first-year graduate students in doctoral programs. While GRE use in fellowship award decisions is a common practice, there is very little validity evidence to support its use in this context. This exploratory qualitative study uses an argument-based validity approach as a conceptual framework to document GRE use systematically in award decisions. The findings from this study indicate that universities use merit-based fellowships to recruit the best and the brightest graduate students. The GRE is used as part of the nominee selection process in departments and is also used in the final selection process by university-wide committees. The GRE scores are primarily used to infer whether students have the baseline knowledge and skills needed to succeed in graduate school. These academic competencies were one of the characteristics the decision makers identified as required for successful doctoral students. The participants stated that the factors for success in graduate school are nebulous; however, the students with high GRE scores and other noteworthy supporting materials are expected to perform strongly in graduate school and, therefore, are worthy of the investment of a merit-based fellowship.
The superfluid phases of liquid 3He: BCS theory

Following the success of the original BCS theory as applied to superconductivity in metals, it was suggested that the phenomenon of Cooper pairing might also occur in liquid 3-He, though unlike the metallic case the pairs would most likely form in an anisotropic state, and would then lead in this neutral system to superfluidity. However, what had not been anticipated was the richness of the phenomena which would be revealed by the experiments of 1972. In the first place, even in a zero magnetic field there is not one but two superfluid phases, and the explanation of this involves ideas concerning "spin fluctuation feedback" which have no obvious analog in metals. Secondly, the anisotropic nature of the pair wave function, which in the case of the B phase is quite subtle, and the fact that the orientation must be the same for all the pairs, leads to a number of qualitatively new effects, in particular to a spectacular amplification of ultra-weak interactions seen most dramatically in the NMR behavior. In t...
3D GPR reveals complex internal structure of Pleistocene oolitic sandbar

Active oolitic sandbars like those in the Bahamas (Figure 1) exhibit complex internal architecture with a multitude of stacked sedimentary structures. Ooids are round, carbonate-coated grains that form in tropical climates. The internal anatomy of carbonate sandbars is often too complex to be captured in one- and two-dimensional data. Outcrops, cores, and 2D geophysical profiles provide a limited vertical view of the geologic record. Depositional processes are confined to the momentary subhorizontal boundary surface between sediment and water or air. Vertical 2D views limit the visibility of features developed on subhorizontal surfaces, making interpretation of 3D internal anatomy and reconstruction of related depositional parameters difficult. Closely spaced 3D data are needed to accurately map sedimentary structures and improve fluid flow modeling used in water and hydrocarbon resource management. 3D reflection seismic imaging has successfully been used to delineate oolitic bars in sub-surface oil field...
Update on attention-deficit/hyperactivity disorder.

Purpose of reviewAttention-deficit/hyperactivity disorder (ADHD) is present in 3% to 10% of children in the United States. Children with ADHD can have academic impairments, social dysfunction, and poor self-esteem. There is also a higher risk of both cigarette smoking and substance abuse. Given this
Amoxicillin in the Treatment of Urinary Tract Infections

Amoxicillin was evaluated in the treatment of 38 patients with bacteriuria who received doses of either 750 mg or 1 g per day for 10 days. Although amoxicillin was effective in eradicating bacteriuria due to susceptible organisms and was very well tolerated, it performed no better than many other drugs already available for the treatment of acute uncomplicated bacteriuria. Amoxicillin is a new penicillin structurally similar to ampicillin, differing only in the hydroxylation of the phenyl side chain. Previous studies indicated that amoxicillin has an antibacterial spectrum comparable to that of ampicillin [1-5], but that it is better absorbed after oral administration and thus provides higher concentrations in serum. Moreover, the excretion of amoxicillin in the urine has been correspondingly greater than that of ampicillin. The present report summarizes the use of amoxicillin in the treatment of 38 patients with infections of the urinary tract.
Preparation and Structural Investigation of Bi16(Sr,Ca)14O38

Single-crystal X-ray diffraction was used to investigate the structure of the ternary oxide of approximate formula Bi 14 (Sr,Ca) 12 O 33 . The crystal examined was found to have a composition Bi 2 Sr 0.68 Ca 1.07 O 4.75 or Bi 16 Sr 5.44 Ca 8.56 O 38 as a result of refinement. It crystallizes in the monoclinic space group (C2/m), with cell parameters a = 21.764 (4) A, b = 4.3850 (13) A, c = 12.905 (3) A, β = 102.72 (2)°, and V 1201.2 (5) A 3 . Strontium and calcium ions were found to substitute for each other. The structure consists of a network of alkaline-earth oxide polyhedra with broad channels parallel to the b axis, in which the bismuth ions reside. Two out of four crystallographically distinct Bi ions form infinite Bi-O zigzag ribbons of edge-linked Bi-O units, while each of the other two form oxygen corner-shared Bi-O chains along b. The lone pair electrons of the Bi ions point toward each other in the channels.
Reputation and Hegemonic Stability: A Game-Theoretic Analysis

We develop and explicate a game-theoretic model in which repeated play, incomplete information, and reputation are major elements. A significant advance of this model is the way it represents cooperation under incomplete information among rational actors of different sizes. The model is used to formalize certain aspects of the “theory of hegemonic stability.” It shows that the “dilemma” or “limits” of hegemonic stability look like natural attributes of games where reputation is involved, unifying both “benevolent” and “coercive” strands of hegemony theory. An example, drawn from recent developments in the Organization of Petroleum-exporting Countries, shows how our model of reputation guides the study of hegemonic regime construction. We conclude by comparing the nature of cooperative behavior under conditions of complete and incomplete information.
Effect of acrylamide intoxication on pyridine nucleotide concentrations and functions in rat cerebral cortex.

Abstract Male rats were given cumulative doses of 428 mg/kg (low dose) and 668 mg/kg (high dose) of acrylamide. Concentrations of oxidized pyridine nucleotides were determined in samples of cerebral cortex from treated and control rats. The concentration of NAD + was significantly increased (P + in cerebral cortices from treated rats, there was little suggestion of an interference with pyridine nucleotide function.
Determination of Plasma Osmolality and Agreement between Measured and Calculated Values in Captive Male Corn Snakes (Pantherophis [Elaphe] guttatus guttatus)

Abstract Twelve adult male corn snakes, Pantherophis (Elaphe) guttatus guttatus, were used for this study. Blood samples were collected via cardiocentesis or caudal tail venipuncture. Plasma chemistries were measured using a standard laboratory chemistry analyzer; these parameters were used to calculate plasma osmolality. Osmolality also was measured using a freezing point osmometer. The osmolality measured with the osmometer in the corn snakes ranged from 304.5 to 373.0 mOsm/kg, with a mean value of 344.5 mOsm/kg. These values are higher than the osmolality of Ringer's solution (310 mOsm/L), lactated Ringer's solution (272 mOsm/L), Plasma-Lyte A® (294 mOsm/L), and Normosol R® (295 mOsm/L) and should be taken into account when replenishing fluids to avoid large shifts in plasma osmolality. Bland Altman plots were used to assess the level of agreement between the measured and calculated osmolalitites. The results of the comparisons showed the highest level of agreement between the measured and calculated o...
A general finite element formulation for fractional variational problems

Abstract This paper presents a general finite element formulation for a class of Fractional Variational Problems (FVPs). The fractional derivative is defined in the Riemann–Liouville sense. For FVPs the Euler–Lagrange and the transversality conditions are developed. In the Fractional Finite Element Formulation (FFEF) presented here, the domain of the equations is divided into several elements, and the functional is approximated in terms of nodal variables. Minimization of this functional leads to a set of algebraic equations which are solved using a numerical scheme. Three examples are considered to show the performance of the algorithm. Results show that as the number of discretization is increased, the numerical solutions approach the analytical solutions, and as the order of the derivative approaches an integer value, the solution for the integer order system is recovered. For unspecified boundary conditions, the numerical solutions satisfy the transversality conditions. This indicates that for the class of problems considered, the numerical solutions can be obtained directly from the functional, and there is no need to solve the fractional Euler–Lagrange equations. Thus, the formulation extends the traditional finite element approach to FVPs.
Application of atomic-force microscopy to studies of microbial interactions with hydrous Fe(III)-oxides

Abstract We are using atomic-force microscopy (AFM), to address the interactions of a Pseudomonas sp. aerobic soil microbe with Fe(III)-(hydr)oxides. Research results to date show that AFM is a viable technique for in-situ and ex-situ imaging of bacteria attached to rnineral surfaces. Delicate microbial structures and mineral surface microtopographies are readily accessible. However, sample preparation has proven to be crucial. For example, we found that an organic extractant used to separate bacteria from particle surfaces left a residue that could be mistaken for dissolution features in AFM images. Additionally, care must be taken to image samples in numerous locations and under a wide variety of conditions. The need for extensive imaging was reinforced by our observations that most reacted particles had no obvious dissolution features, but a small fraction of particles were extensively eroded. Hence, microbe-Fe(III)-(hydr)oxide interactions lead to enhanced dissolution, but the dissolution process is heterogeneous in nature. Thus, although AFM imaging of such complex systems is difficult and time-consuming, a painstaking approach is needed.
Bilateral cochlear implantation

There is rapidly emerging data that clearly show the benefits of bilateral cochlear implantation (CI). For those surgeons who wish to begin bilateral implantation, several important technical differences from traditional implant surgery must be considered. First, the surgeon must determine whether to perform bilateral simultaneous CI (ie, when both implants are placed during the same procedure) or bilateral sequential CI placement of each implant at separate operations. Technical issues that must be considered during sequential implantation include symmetrical placement of the second implant receiver, the avoidance of monopolar cautery during the procedure, and careful preservation of the chorda tympani. Additional considerations during simultaneous implantations include anticipation of increased operating time, including both ears in the preparation, reduced range of neck rotation, bilateral facial nerve monitoring, the use of a headlight, and symmetrical placement of the implants.
SU‐E‐T‐727: Evaluation of Eclipse AAA Dose Calculation Accuracy in the Presence of a Titanium Spinal Fixation Device

Purpose: To determine whether the Eclipse's AAA algorithm can accurately predict doses in the presence of hardware. Methods: A titanium spinal fixation device was attached to a spine model to mimic its spatial orientation in patient. The model was immobilized to a plastic plate to form a rigid device. Posterior spine irradiation was simulated by positioning the device inside a PTW water tank with 270 degree gantry irradiation. Absolute doses and relative dose distributions were measured using ion chamber and OSLD. Lateral spine irradiation was simulated by placing the device in a water tank with 0 degree gantry irradiation. Planar doses were measured using a SunNuclear MapCheck device for 6 MV open and intensity‐modulated beams. Above experiement setups were reproduced in Eclipse from CTimages with correct electron densities assigned to materials used in the experiments, e.g. electron density 4.0 for the titanium device. Doses were calculated using AAA 8.9 algorithm and compared with measurements. Results: In posterior spine irradiation, doses were measured respectively for 7×10 and 10×15 cm open fields. Measured dose outputs agreed with calculations within 2.5% at all selected locations along the spinal canal and under the titanium cage. Excellent agreements ( 98% agreements between the measured and the calculated planar doses for all tested open and intensity‐modulated fields. Conclusions: Eclipse's AAA 8.9 algorithm can reasonably accurately predict doses in the spine region in the presence of a titanium spinal fixation device.
Is it an accident? Recurrent traumatic life events in level I trauma center patients compared to the general population

The trauma history screen developed for the National Comorbidity Survey (NCS) was used to assess prior trauma in a representative sample of injured acute care inpatients (n = 251). Adjusted logistic regressions compared the trauma histories of intentionally (n = 66) and unintentionally (n = 185) injured patients with NCS participants (n = 5873). Whereas only 11% of NCS respondents reported 4 or more lifetime traumas, 61% of intentionally injured patients (Adjusted OR = 7.97, 95% CI = 4.33, 14.68) and 40% of unintentionally injured patients (Adjusted OR = 4.26, 95% CI = 2.94, 6.16) reported 4 or more lifetime traumas. In adjusted analyses, inpatients were at increased risk for reporting all types of trauma except combat. Screening and intervention procedures that address the unique characteristics of this high-risk patient population are needed in the acute care setting.
A study of resonance production in six-pronged π−p interactions at 7.0 GeV/c

Abstract We have analyzed six-prong events from π − p interactions in a hydrog bubble chamber with a beam momentum of 7.0 GeV/ c . The total six-prong cross section is 2.40 ± 0.15 mb. The reactions studied are: (i) π − p→ π − π − π − π + p (0.26±0.03 mb) . (ii) π − p→ π − π − π − π + p π o (0.63 ± 0.09 mb) . (iii) π − p→ π − π − π − π + π + n (0.29 ± 0.04 mb). There is significant production of Δ ++ (1238) and ϱ (760) in reaction (1). Reaction (2) shows Δ ++ (1238). The p π o mass distribution in reaction (2) shows an enhancement at 1540 ± 20 MeV/ c 2 with a width of 100 ± 40 MeV/ c 2 (interpreted as N ∗ (1520)). In the + π + π − π − invariant mass distribution. We observe two enhancements - one at 1085 ± 20 MeV/ c 2 with a width of 70 ± 30 MeV/ c 2 . The second at 1470 ± 20 MeV/ c 2 with width 60 ± 25 MeV/ c 2 these two enhancements appear less prominently in the + π + π − π − mass spectrum in reaction (3).
The menstrual rhythm.

Abstract (1) The human menstrual cycle was studied as a rhythm by applying graphic techniques used previously to study circadian rhythms. (2) Menstrual rhythms appeared to freerun, that is, progressed in time without any obvious external timesetting signals.
Novel echogenic drug-immunoliposomes for drug delivery.

Rationale and Objectives: We have developed novel echogenic immunoliposomes (ELIPs) that can be antibody-conjugated for the specific highlighting of atheroma and atheroma components. The utility of these agents for regional drug delivery has not been evaluated previously. We chose to use an antibiotic as the prototype drug. The concept that an infectious agent may affect the development and progression of atherosclerosis has stimulated trials on the use of antibiotics for coronary syndromes. However, these agents are given systemically with concomitant problems. Development of an agent for local drug delivery may obviate adverse effects and improve treatment efficacy. The aim of this study was to evaluate the potential of our ELIPs for drug incorporation and to demonstrate efficient drug delivery to cultured cells. Methods: Azithromycin was incorporated into the ELIPs during development. Free drug was removed with a Sephadex G-50 column. Acoustic properties were evaluated using an intravascular ultrasound catheter and quantified by computer-assisted videodensitometry. Human umbilical arterial endothelial cells were infected with Chlamydia pneumoniae. Cells were treated with the drug-ELIP complexes, and infection-forming units were counted using fluorescence techniques. Results: We were able to incorporate a drug into the ELIPs with retention of acoustic properties. The drug-ELIP complex demonstrated effective inhibition of microbial growth in endothelial cells (P < 0.001 vs. empty liposomes and control). Conclusions: We have developed a novel acoustic drug-liposomal agent that can deliver drugs to cultured cells. Although in vivo translation is required, this technique has potential for site-specific drug delivery.
Immunofluorescent studies of the development of pre-B cells, B lymphocytes and immunoglobulin isotype diversity in humans

Immunofluorescent techniques were used to examine several aspects of B cell ontogeny in humans. Large lymphoid cells containing intracytoplasmic IgM (pre-B cells) were present in fetal liver as early as 7 weeks of gestation, approximately 2 weeks prior to the appearance of surface IgM positive (sIgM+) B lymphocytes. Pre-B cells outnumbered sIgM+ B lymphocytes in fetal liver up until the 13th week of gestation. In fetuses older than 13 weeks, pre-B cells and sIgM+ B lymphocytes were present in approximately equal proportions in liver and bone marrow. Pre-B cells in fetal liver, and fetal and adult marrow, were large and small (indicating a heterogeneous population of cytoplasmic IgM+. SIg- cells in these sites), while only the small pre-B cells were present in fetal spleen, blood and lymph node. Lymphocytes bearing sIgG were detected earlier than those bearing sIgD or sIgA, which were present by the 12th gestational week. Using double-staining techniques, we determined that during fetal life, (a) the proportion of B lymphocytes bearing only sIgM, as opposed to those bearing both sIgM and sIgD, was much higher in liver and bone marrow than in spleen, blood and lymph node, and (b) sIgG, sIgA and sIgD appear independently on lymphocytes bearing sIgM. Studies of the frequency of double-stained cells for each combination of the four sIg isotypes indicated that B lymphocytes from neonatal humans may simultaneously bear three or more sIg isotypes, whereas sIgG+ and sIgA+ B lymphocytes in adult blood usually express only the single isotype. Lower concentrations of anti-y antibodies were required for modulation of sIgM from B lymphocytes of fetal liver and adult bone marrow than for equivalent removal of sIgM from circulating B cells of mature individuals. In conjunction with data obtained in mice, our observations indicate that (a) the presence of large and small pre-B cells, (b) a high ratio of sIgM single to sIgM.sIgD double B lymphocytes, and (c) increased sensitivity to modulation of B cell sIgM by divalent anti-μ antibodies define the fetal liver and adult bone marrow as bursa-equivalent sites in humans. Our results are consistent with a model of isotype diversification in which immature sIgM+ cells give rise to B cell sublines devoted to synthesis of each of the Ig classes, and sIgD is secondarily expressed on unstimulated B cells of all of these sublines.
Wave propagation in the early stages of aggregation of cellular slime molds.

Abstract A detailed theory of the velocity of propagation of the acrasin pulse responsible for the aggregation of some of the cellular slime molds is presented. The ingredients are diffusion of acrasin, triggering after a threshold concentration is reached, an intracellular delay between the reaching of threshold and subsequent release of acrasin, the destruction of acrasin by acrasinase, and an intracellular refractory period. It is suggested that the rate limiting factor in the velocity of propagation is probably the intracellular delay and not intercellular diffusion. It is shown that there is a critical density of amebae below which the waves cannot propagate. The number of neighboring amebae triggered simultaneously by the propagating wave, and therefore the spatial width of the pulse tends to increase with density. Rough estimates are given for the number of acrasin molecules per pulse and for its threshold concentration.
Ontogenetic Variation in Digestion by the Herbivorous Lizard Ctenosaura pectinata

Abstract I tested the hypothesis that an animal with an ontogenetic diet shift must have different digestive efficiencies for foods that correspond to its diet shift, so that nutrient and energy extraction are maximized. The iguanine lizard Ctenosaura pectinata undergoes an ontogenetic diet shift from eating insects as a juvenile to plants as an adult. When fed six different pure foods from the natural diets of different age classes, C. pectinata assimilated nutrients and energy differently depending on food type and age class. Extraction of energy and nutrients in insect larvae was maximized by juvenile lizards. Calcium, phosphorus, and energy were readily assimilated from flowers and fruit by immature and adult lizards. Magnesium levels were highest in leaves and were extracted by immature and adult lizards, but xenobiotic effects of one plant leaf (Croton suberosus), eaten by adults, killed juvenile lizards. Although juvenile C. pectinata ate some flowers (Senna wislizenii) naturally, they were less ef...
Clutter Suppression Properties of Weighted Pulse Trains

A common but troublesome requirement on radar sensors is the detection of a target in the interference from undesired scatterers, or clutter. Systems with coherent processing of pulse trains are uniquely suited for the purpose because, with pulse trains, it is possible to concentrate the receiver output for particular values of Doppler and thus suppress the clutter by Doppler filtering. This paper discusses to what degree the effectiveness of the method can be enhanced by tapering, or weighting, of the pulse amplitudes. The general results are illustrated by computer-plotted response functions for weighted pulse trains. The clutter suppression efficiency of weighting is calculated both for unilateral weighting in the receiver and for bilateral weighting in both receiver and transmitter. The significance of additional phase weighting is discussed and the results for pure amplitude weighting are compared with publishedwork on phase and amplitude weighting.
A second order self-consistent IMEX method for radiation hydrodynamics

We present a second order self-consistent implicit/explicit (methods that use the combination of implicit and explicit discretizations are often referred to as IMEX (implicit/explicit) methods [2,1,3]) time integration technique for solving radiation hydrodynamics problems. The operators of the radiation hydrodynamics are splitted as such that the hydrodynamics equations are solved explicitly making use of the capability of well-understood explicit schemes. On the other hand, the radiation diffusion part is solved implicitly. The idea of the self-consistent IMEX method is to hybridize the implicit and explicit time discretizations in a nonlinearly consistent way to achieve second order time convergent calculations. In our self-consistent IMEX method, we solve the hydrodynamics equations inside the implicit block as part of the nonlinear function evaluation making use of the Jacobian-free Newton Krylov (JFNK) method [5,20,17]. This is done to avoid order reductions in time convergence due to the operator splitting. We present results from several test calculations in order to validate the numerical order of our scheme. For each test, we have established second order time convergence.
The Polls: America's Most Important Problems Part II: Regional, Community, and Personal

THE most important problem question helps us understand both the broad strokes and fine details of recent American history. It illuminates important secular trends such as the emergence and disappearance of civil rights as a social concern and gauges the impact on the public consciousness of specific events from riots to recessions. The parallel series on sectional, community, and personal problems add even greater depth to our historical and sociological understanding, especially by demonstrating that problems frequently differ across frames of reference. The most important problem questions are invaluable for both portraying and explaining recent American history and the social change American society has been undergoing.' Tracking trends on the sectional, community, and personal problem questions (Tables 1, 2, and 3) add considerable information about the post-World War II period (each of these series starts in the mid to late forties about a decade after the national most important problem series). These variants are not merely national concerns writ small. Typically, these variants bring to mind quite different sets of problems. Rather than having only one salient problem and expressing that in national, regional, local, and personal contexts, people often chose different problems as the reference changes.2 The largest and most obvious
Hunters ring dinner bell for Ravens: Experimental evidence of a unique foraging strategy

We have long known that corvids are adaptively flexible in behavior, but have rarely tested their flexibility and creativity in solving problems outside the laboratory. Through a carefully controlled experiment conducted in the wild, I have found that Common Ravens (Corvus corax) fly toward gunshot sounds, presumably in order to locate animal gut piles left by hunters. This is the first conclusive evidence of any scavenger species pursuing gunshots. Furthermore, ravens exhibited this behavior only when gunshots were fired from within forested habitat, when the shots may be most valuable to them for locating gut piles. Interestingly, raven behaviors suggest that they may have learned the usefulness of gunshots by substituting them for other previously known sounds already used to locate food in the wild.
Recapitulation of Protein Family Divergence using Flexible Backbone Protein Design

We use flexible backbone protein design to explore the sequence and structure neighborhoods of naturally occurring proteins. The method samples sequence and structure space in the vicinity of a known sequence and structure by alternately optimizing the sequence for a fixed protein backbone using rotamer based sequence search, and optimizing the backbone for a fixed amino acid sequence using atomic-resolution structure prediction. We find that such a flexible backbone design method better recapitulates protein family sequence variation than sequence optimization on fixed backbones or randomly perturbed backbone ensembles for ten diverse protein structures. For the SH3 domain, the backbone structure variation in the family is also better recapitulated than in randomly perturbed backbones. The potential application of this method as a model of protein family evolution is highlighted by a concerted transition to the amino acid sequence in the structural core of one SH3 domain starting from the backbone coordinates of an homologous structure.
Modeling the Potential Impact of Host Population Survival on the Evolution of M. tuberculosis Latency

Tuberculosis (TB) is an infectious disease with a peculiar feature: Upon infection with the causative agent, Mycobacterium Tuberculosis (MTB), most hosts enter a latent state during which no transmission of MTB to new hosts occurs. Only a fraction of latently infected hosts develop TB disease and can potentially infect new hosts. At first glance, this seems like a waste of transmission potential and therefore an evolutionary suboptimal strategy for MTB. It might be that the human immune response keeps MTB in check in most hosts, thereby preventing it from achieving its evolutionary optimum. Another possible explanation is that long latency and progression to disease in only a fraction of hosts are evolutionary beneficial to MTB by allowing it to persist better in small host populations. Given that MTB has co-evolved with human hosts for millenia or longer, it likely encountered small host populations for a large share of its evolutionary history and had to evolve strategies of persistence. Here, we use a mathematical model to show that indeed, MTB persistence is optimal for an intermediate duration of latency and level of activation. The predicted optimal level of activation is above the observed value, suggesting that human co-evolution has lead to host immunity, which keeps MTB below its evolutionary optimum.
Structure and Properties of Naphthalene-Containing Polyesters. 4. New Insight into the Relationship of Transesterification and Miscibility

It is generally agreed in the literature that transesterification leads to or enhances miscibility; that is, transesterification is a necessary condition for miscibility in the polyester blends. We...
An organism-centered approach to some community and ecosystem concepts

Abstract We present a discussion of the ecological concept of the niche based on the perspective of the individual organism, rather than that of a population or species. This discussion is then expanded to include other related ecological concepts such as guild, environment, habitat and functional group. Using the individual as the focus permits the development of a system of concepts which, we believe, approximate the way that ecological interactions occur in nature.
Effects of firing cycle and surface finishing on distortion of metal ceramic castings

The "as-cast" fit of metal ceramic restorations has been reported to deteriorate during the high-temperature firing cycles used for application of porcelain veneer. In this study, thermocycling and surface finishing or cold working were examined for their effects on marginal adaptation of metal ceramic castings. Methods for minimizing the loss of marginal adaptation were evaluated, and casting variables were eliminated by construction of acrylic resin measuring dies directly in the restorations. Thermocycling of metal ceramic restorations resulted in increased marginal openings, and all of the loss of marginal fit occurred during the first thermocycling of the alloy. The restorations that were cold worked and then oxidized by conventional manipulation had substantially more marginal opening than any other group. A fourfold, statistically significant improvement (p < 0.001) in the marginal adaptation of a metal ceramic restoration was observed when the initial thermal cycle was completed before the specimens were finished.
Role of ion transport in actuation of ionic polymeric-platinum composite (IPMC) artificial muscles

The role of cation transportation under the effect of an electric field on the actuation of the ionic polymeric- platinum composite artificial muscles is studied. Nafion-117 was platinized by different methods including in situ chemical reduction, physical vapor deposition and electroplating. The strips of membranes platinized by different methods were tested under the effect on an electric field either in the air or water. The extent of the strip bending was correlated with the history of the membrane platinization. Three different mechanisms that could explain the bending of ionic polymeric-platinum composite artificial muscles were reviewed. The history of the membrane platinization together with the extent of bending observed when an electric field was applied identified the electrostatic between the membrane and the platinum particles as the main contributor to the actuation capability in the platinized membrane under the effect of an electric field.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.