cssi/SciSciGPT-SciSciNet huggingface dataset:
Plasma proteins have a ticket to ride the blood-brain barrier

Analysis of labeled plasma proteins reveals a shift from receptor-mediated brain uptake to less specific transcytosis that occurs with aging.
Data analytics in Association to Advance Collegiate Schools of Business–accredited U.S. university accounting programs: A quantitative research study

The impact of data analytics on the accounting profession has been discussed for more than 15 years, accompanied by increasingly fervent calls from employers for an escalating level of data analyti...
Occupational stress among farm and ranch operators in the midwestern United States.

BACKGROUND: This study used surveillance data from 2018 and 2020 to test the stability of work-related strain symptoms (high stress, sleep deprivation, exhaustion) with demographic factors, work characteristics, and musculoskeletal symptoms among farm and ranch operators in seven midwestern states of the United States. METHODS: Cross-sectional surveys were conducted among farm and ranch operators in 2018 (n = 4423) and 2020 (n = 3492). Operators were asked whether, in the past 12 months, they experienced extended work periods that resulted in high stress levels, sleep deprivation, exhaustion/fatigue, or other work-related strain symptoms. Covariates included personal and demographic factors, work characteristics, number of injuries, work-related health conditions, and exposures on the operation. Summary statistics were tabulated for explanatory and outcome variables. The classification (decision) tree approach was used to assess what variables would best separate operators with and without reported strain symptoms, based on a set of explanatory variables. Regularized regression was used to generate effect estimates between the work strain variables and explanatory variables. RESULTS: High stress level, sleep deprivation, and exhaustion were reported more frequently in 2018 than 2020. The classification tree reproduced the 2018 model using 2020 data with approximately 80% accuracy. The mean number of reported MSD symptoms increased slightly from 1.23 in 2018 to 1.41 in 2020. Older age, more time spent in farm work, higher gross farm income (GFI), and MSD symptoms in six body regions (ankles/feet, knees, lower back, neck, shoulders, wrists/hands) were associated with all three work strain symptoms. CONCLUSIONS: Musculoskeletal pain and discomfort was a strong predictor for stress, sleep deprivation, and exhaustion among farmers and ranchers. This finding indicates that reducing MSD pain and discomfort is beneficial for both physical and mental health.
Social behavior of captive Indochinese and insular long-tailed macaques (Macaca fascicularis) following transfer to a new facility

There are measurable differences in behavior, physiology, social organization, and geographic distribution within and between various species of macaques. We collected information on the social behavior of captive Macaca fascicularis from Indochina and island populations after they had been transferred to a new environment and new social groups. While some changes in behavior occurred over time, we found no decrease in high levels of agonistic behaviors. We interpret this finding in light of previous research reporting that long-tailed macaques show low levels of habitatuation to novelty and are highly aroused in comparison to other macaque species. We found predictable differences in behavior for males, females, and infants, in which infants played more, females had higher levels of contact proximity to other individuals, and males exhibited more sexual and threat behavior. A comparison of social behavior in long-tailed macaques from different origins indicate that Indochinese macaques are generally less affiliative and Indochinese males are more aggressive than their insular counterparts. Differences among macaque species, and within the fascicularis-group, should be considered in management of captive colonies and when interpreting research data.
Multi-objective optimization for draft scheduling of hot strip mill

A multi-objective optimization model for draft scheduling of hot strip mill was presented, rolling power minimizing, rolling force ratio distribution and good strip shape as the objective functions. A multi-objective differential evolution algorithm based on decomposition (MODE/D). The two-objective and three-objective optimization experiments were performed respectively to demonstrate the optimal solutions of trade-off. The simulation results show that MODE/D can obtain a good Pareto-optimal front, which suggests a series of alternative solutions to draft scheduling. The extreme Pareto solutions are found feasible and the centres of the Pareto fronts give a good compromise. The conflict exists between each two ones of three objectives. The final optimal solution is selected from the Pareto-optimal front by the importance of objectives, and it can achieve a better performance in all objective dimensions than the empirical solutions. Finally, the practical application cases confirm the feasibility of the multi-objective approach, and the optimal solutions can gain a better rolling stability than the empirical solutions, and strip flatness decreases from (0±163) IU to (0±45) IU in industrial production.
Effect of gene amplification on mercuric ion reduction activity of Escherichia coli.

The mercury resistance (mer) operon of plasmid R100 was cloned onto various plasmid vectors to study the effect of mer gene amplification on the rate of Hg{sup 2+} reduction by Escherichia coli cells. The plasmids were maintained at copy numbers ranging from 3 to 140 copies per cell. The overall Hg{sup 2+} reduction rate of intact cells increased only 2.4-fold for the 47-fold gene amplification. In contrast, the rate of the cytoplasmic reduction reaction, measured in permeabilized cells, increased linearly with increasing gene copy number, resulting in a 6.8-fold overall amplification. RNA hybridizations indicated that mRNA of the cytoplasmic mercuric reductase (merA gene product) increased 11-fold with the 47-fold gene amplification, while mRNA of the transport protein (merT gene product) increased only 5.4-fold. Radiolabeled proteins produced in maxicells were used to correlate the expression levels of the merpolypeptides with the measured reduction rates. The results indicated that, with increasing gene copy number, there was an approximately 5-fold increase in the merA gene product compared with a 2.5-fold increase in the merT gene product. These data demonstrate a parallel increase of Hg{sup 2+} reduction activity and transport protein expression in intact cells plasmids with different copy numbers. In contrast, the expressionmore » level of the mercuric reductase gene underwent higher amplification then that of the transport genes at both the RNA and protein levels as plasmid copy number increased.« less
Efficient implementation of FIR filters using bit-level optimized carry-save additions

A widely used technique to implement high-speed fixed-coefficients FIR filters in VLSI circuits is to use carry-save additions (CSA) to defer the time-consuming carry-propagations. This paper shows that by exploiting the unequal wordlength of the partial products generated by the fixed-coefficients, significant savings can be achieved by optimizing the carry-save representation at the bit-level. The key in our proposed technique is to allow for more than two signals per bit position, so that we gain flexibility in the bit-level implementation of CSA arrays. We have applied our algorithms to the optimization of high-speed digital FIR filters and have achieved 15% to 30% savings (weighted cost) in the overall filter implementation array in comparison to the standard carry-save implementation.
Shift and rotation invariant texture recognition with neural nets

Shift and rotational invariant approaches based on neural nets have been proposed in the literature for the purpose of a training for classification of patterns independently of their position and orientation. The training usually requires the presentation of preprocessed patterns in the different positions and orientations that are involved in the testing. This means high dimensional input vectors and large number of training patterns. This situation can be simplified by using rotation insensitive information in the construction of the input vectors. The use of representative input vectors from a pool containing all possible input vectors (ideal) accounts for the shift invariance characteristic of the training. This approach leads to a considerable time saving in the learning phase of the net because of the reduction of the dimensionality of the input vectors and the reduction of the number of training patterns required. This in turn reduces the number of hidden nodes thus reducing the size of the processor itself upon implementation. The example used here is the classification of textures that show directionality. >
Chapter IX Solid State Masers

Publisher Summary Spin systems in solids offer the possibility to create an emissive or “maser” condition. The thermal equilibrium of the spin levels can be upset in a variety of ways. This is particularly easy at low temperatures where the spin-lattice relaxation times are long. The methods to create a larger population in a state with higher energy are not restricted in principle to spin systems; but in practice, these are the only systems in condensed matter to which they have been applied successfully thus far. The methods are: 1. sudden change in external parameter; 2. adiabatic rapid passage; 3. the 180˚ pulse; and 4. pumping in multiple level systems. In the final section of the chapter, optical pumping in solids at low temperature and some other devices are mentioned, which are closely related to masers. A device based on stimulated emission of radiation is defined as maser. Whether the device operates in the microwave region or in another part of the electromagnetic spectrum is less important.
Clinical correlates of co‐occurring cannabis and tobacco use: a systematic review

Aims A growing literature has documented the substantial prevalence of and putative mechanisms underlying co-occurring (i.e., concurrent or simultaneous) cannabis and tobacco use. Greater understanding of the clinical correlates of co-occurring cannabis and tobacco use may suggest how intervention strategies may be refined to improve cessation outcomes and decrease the public health burden associated with cannabis and tobacco use.
Extrinsic Complex Projective Geometry

Let P N denote N-complex-dimensional complex projective space, and M a complex manifold. Consider complex analytic mappings f: M → P N . A general problem of extrinsic geometry is to relate the intrinsic invariants of M with the extrinsic invariants of such maps1.
The large vestibular aqueduct syndrome

It has long been known that abnormally large vestibular aqueducts may accompany congenital malformations of the cochlea and semicircular canals. Recently, enlargement of the vestibular aqueducts as the sole radiographically detectable inner ear anomaly has been recognized as a distinct pattern of congenital inner ear malformation. Pathogenesis of the large vestibular aqueduct syndrome probably stems from an early derangement in the embryogenesis of the endolymphatic duct. This anomaly appears to be relatively common in children with sensorineural hearing loss and is probably significantly underdiagnosed. Hearing loss is typically bilateral and progressive, with stepwise rather than fluctuant hearing decrements often triggered by relatively minor head trauma. A review of 17 patients (33 ears) revealed an average hearing level at presentation of 57 dB with a speech discrimination score of 66%. Considerable variability exists in hearing level among affected ears, ranging from normal hearing (4%) to profound deafness (39%). In 12 patients (23 ears) with an average long-term follow-up of 7.3 years, the hearing loss progressed by an average of 25 dB, with a drop of 29% in speech discrimination over the period of observation. An endolymphatic to subarachnoid shunt was performed on seven ears in an effort to stabilize hearing. Four of these ears had a substantial immediate postoperative drop in hearing. For this reason, endolymphatic sac surgery is not recommended for patients with this deformity.
Effects of cholecystokinin (CCK) and other secretagogues on isoforms of protein kinase C (PKC) in pancreatic acini

We used rat pancreatic acini and measured the effects of various agents on digestive enzyme secretion, diacylglycerol (DAG) and the cellular distribution of protein kinase C (PKC) enzyme activity as well as isoforms of PKC determined by quantitative immunoblot analysis. TPA, but not CCK-8, caused translocation of PKC enzyme activity from the cytosol fraction to the membrane fraction. Immunoblot analysis detected PKC-alpha, PKC-delta, PKC-epsilon and PKC-zeta. PKC-beta, PKC-gamma and PKC-eta were not detected. TPA caused translocation of all isoforms from cytosol to membrane, whereas CCK-8 caused translocation of PKC-delta and PKC-epsilon, carbachol caused translocation of PKC-epsilon, and bombesin and secretin caused no detectable translocation of any isoform. Specific receptor antagonists could prevent, as well as reverse completely, the translocation of PKC isoforms caused by CCK-8 or carbachol. Agonists added in sequence with an interposed addition of a specific receptor antagonist caused cycling of PKC-epsilon between cytosol and membrane fractions. Each receptor-mediated agonist that caused translocation of PKC also increased DAG, and with CCK-8 and carbachol cycling of PKC-epsilon between cytosol and membrane was accompanied by corresponding cyclic changes in cellular DAG. CCK-JMV-180, bombesin and secretin increased DAG but did not cause translocation of any PKC isoform. Translocation of a PKC isoform could be accounted for by whether the increased DAG originated from PIP2 (accompanied by translocation) or from phosphatidylcholine (no accompanying translocation). Thus it appeared that DAG, in pancreatic acini, is functionally compartmentalized depending on the source of the lipid. Studies using CCK-8 and CCK-JMV-180 indicated that occupation of the low affinity state of the CCK receptor by either peptide increased DAG from phosphatidylcholine, whereas occupation of the very low affinity state by CCK-8 increased DAG from PIP2 and caused translocation of PKC-delta and PKC-epsilon. TPA stimulated amylase secretion, indicating that activation of PKC can stimulate enzyme secretion; however, with the various receptor-mediated secretagogues there was no consistent, unequivocal correlation between translocation of an isoform of PKC and accompanying changes in enzyme secretion.
Modelling regional climate changes: influences of recent global warming and irrigation in California

A regional climate model is used to explore the influences of global warming and land use changes on past climate change in California. The model experiments utilize a methodology, which is suggested by an exploration of the climate change in Califomia. The model experiments utilize a methodology, which is suggested by an exploration of the uncertainties associated with a regional model forced by global climate model output. The results are based primarily on an analysis of the output of three model runs. In the first, we prescribe modern land cover and irrigation conditions and force the model with recent meteorological conditions. In the second, we prescribe an historical land cover without irrigation and force with past conditions, derived from a global coupled climate model. In the third, we prescribe the historical land cover without irrigation, but force with the recent conditions. The model results show that global warming has a large effect on precipitation, snow water, surface temperature, low level winds and soil moisture They also show in summer that irrigation has a strong effect on the differences between recent and past conditions in maximum temperature, surface latent and sensible heat fluxes, surface moisture, and surface humidity. The primary uncertainty associated with these conclusions is related to the use of boundary forcing from a single global climate model.
Bicycling and Transit: A Marriage Unrealized:

When effectively integrated with transit services, bicycling may achieve various environmental, health, and congestion-mitigation benefits for communities. A successful marriage between the two will most likely result in increasing (a) the catchment area and subsequent patronage of transit, (b) the efficiency of transit, and (c) the overall demand for cycling. A core problem, however, exists in that the predominant approach for integrating bicycling and transit vehicles frequently runs against capacity restraints. Effectively integrating bicycling and transit requires analysis of a broad range of alternatives that consider the travel patterns and needs of individuals and accompanying urban form characteristics. To fill a void in the literature concerning integrating bicycling and transit, this paper surveys existing knowledge about the two modes, describes three innovative initiatives that show promise in addressing capacity limitations, and sketches an analysis framework for communities and transit agenc...
Accumulation of marginal zone B cells and accelerated loss of follicular dendritic cells in NF-κB p50-deficient mice

Background Marginal zone (MZ) B cells play important roles in the early phases of humoral immune responses. In addition to possessing an inherent capacity to rapidly differentiate into antibody secreting cells, MZ B cells also help to regulate the fate of both T-independent and T-dependent blood-borne antigens in the spleen. For T-dependent antigens, MZ B cells bind IgM-antigen complexes in a complement-dependent manner. Once MZ B cells bind IgM-containing immune complexes (IgM-IC), they transport them into B cell follicles for deposition onto follicular dendritic cells (FDCs), an important component of secreted IgM's ability to enhance adaptive immune responses. To further define the requirement for MZ B cells in IgM-IC deposition, mice deficient in the NF-κB protein p50, which have been reported to lack MZ B cells, were analyzed for their ability to trap IgM-IC onto FDCs.
Crystal structure of a soluble form of the human T cell coreceptor CD8 at 2.6 A resolution.

Abstract A secreted fragment of the extracellular portion of human CD8α has been expressed in CHO cells, and a deglycosylated and proteolyzed form of this fragment has been crystallized. We report here the crystal structure of this fragment as refined at 2.6 A resolution. The structure was solved by molecular replacement using a superposition of ten variable domains from immunoglobulin light chains as the search model. Only the N-terminal 114 amino acids of CD8α are visible in the electron density maps. The domain formed by these residues possesses a fold typical of immunoglobulin variable domains and associates to form F v -like homodimers.
Stochastic Modeling of the Bulk Thermal Conductivity for Dense Carbon Nanotube Networks

A computational, physics-based, bulk thermal conductivity model of a neat carbon nanotube network at room temperature is developed using classical finite element techniques. The model is based on experimentally available stochastic distributions of length, diameter, chirality, and orientation, and uses theoretical results for thermal contact resistance from the literature and molecular dynamics simulations for the stochastic nature of tube separation distance. Understanding the thermal transport properties of carbon nanotube networks at various operating temperatures is crucial for the industrial acceptance of these materials in aerospace and electrical applications. Mechanisms of thermal transport are discussed including; thermal conductivity along the tube and inter-contact resistance between the tubes, where the later is considered the dominating factor. The effect of variations of several of the aforementioned stochastic factors influencing the bulk conductivity is investigated, and results demonstrate that changes in the nanotube length play a significant role in improving the bulk conductivity of the network. In addition, a brief study into localized power flow is presented and lends insight into a possible cause of premature network failure.Copyright © 2009 by ASME
Involvement of cholesterol in synaptic vesicle swelling

Studies demonstrate that cholesterol plays a critical role in the regulation of neurotransmitter release and that secretory vesicle swelling is a requirement for the regulated expulsion of intravesicular contents during cell secretion. In view of this, the involvement of cholesterol in synaptic vesicle swelling was hypothesized and tested in the present study, using isolated synaptic vesicles from rat brain and the determination of their swelling competency in the presence and absence of cholesterol. The involvement of the water channel aquaporin-6 (AQP-6) and proton pump vH+-ATPase in GTP-Gαo-mediated synaptic vesicle swelling has been reported previously. Mastoparan, the amphiphilic tetradecapeptide from wasp venom, known to activate the GTPase activity of Gαo/i proteins, stimulates synaptic vesicle swelling in the presence of GTP. In the current study, using nanometer-scale precision measurements of isolated synaptic vesicles, we report for the first time that depletion of cholesterol from synaptic ves...
The Capelli identity, tube domains, and the generalized Laplace transform

The key result in this paper is a proof of a large class of identities, generalizing the Capelli identity [Cl. The Capelli identity is a centerpiece of 19th century invariant theory. It asserts the equality of two differential operators on the n2-dimensional space M(n, R) of n x n real matrices. Let E, denote the ijth elementary matrix, let xii denote the linear functions on M(n, R) dual to E,, and write 3, for the partial differential operator a/ax,. Then this identity says
Incentivos fiscales para los Business Angels en España

Business Angels have become more important in Spain in the last years, as proved by the different proposals submitted in the Congress between 2005 and 2013. In these proposals Business Angels have been recognized as an alternative source of finance to traditional financing and an important support for entrepreneurs. In these proposals, different political groups, at different times, have requested a legal framework and tax incentives for Business Angels. This article has three parts. In the first part, describes the long way to the recognition of tax incentives on the part of the State, to the Business Angels in the Income Tax, as it emerges from the draft Bill to support entrepreneurs and their internationalization of July of 2013. In the second part analyzes the treatment received by these investments in the Corporation Tax, Property Tax and Inheritance Tax. Finally, the third part deepens in Income Tax, focusing especially on the deductions, approved by Autonomus Communities for acquisition of shares.
Nutritional value of Phaeocystis pouchetii (Prymnesiophyceae) and other phytoplankton for Acartia spp. (Copepoda): ingestion, egg production, and growth of nauplii

Ingestion and egg production by Acartia hudsonica (5°C) and A. tonsa (10°C) from Narragansett Bay, Rhode Island, USA, was measured in the laboratory over a range of concentrations of the prymnesiophyte Phaeocystis pouchetii and the diatom Skeletonema costatum. Both Acartia species reproduced well when fed unialgal diets of S. costatum. Egg production by females fed P. pouchetii, either as gelatioous colonies (primarily >200 μm in diameter) or solitary cells (3 to 5 μm), was not significantly different than that of starved females. Acartia spp. fed selectively on S. costatum in multialgal treatments. The presence of P. pouchetii did not reduce ingestion of S. costatum; the availability of S. costatum did not increase ingestion of P. pouchetii. Nauplii of A. hudsonica grew equally well on separate diets of P. pouchetii and Isochrysis galbana, two flagellates of similar size. Adult Acartia spp. reproduced poorly when fed these phytoplankton, suggesting that particle size may be more important than food quality in describing the responses. Grazing by Acartia spp. does not directly impact the dynamics of P. pouchetii, but may indirectly contribute to blooms of this prymnesiophyte by removal of competing phytoplankton.
Introduction: visualizing evidence and inference in legal settings

By now it is an old story: legal scholarship in the English-speaking world about the law of evidence began to change in the late 1960s and early 1970s. This shift in the direction of Evidence scholarship came to be known as the ‘New Evidence Scholarship’—‘NES’, for short. A characteristic (but not universal) feature of much of NES—particularly in the early days—was a preference for formal mathematical argument about evidence and inference and about decisions based on uncertain evidence and inference. NES aroused controversy from the moment of its birth (or rebirth). Laurence Tribe almost succeeded in turning NES into an example of sudden infant death syndrome; his powerful 1971 attack on ‘trial by mathematics’ almost succeeded in killing off the baby.1 Other observers, while not necessarily rejecting the need for a shift in the direction of Evidence scholarship, followed the anti-mathematicist trail that Tribe had blazed. (But scholars such as Richard Lempert, David Kaye and David Schum saved the mathematicist branch of the new scholarship from premature oblivion.2) Many of the attacks on mathematical analysis of evidential inference were misdirected; many of them—probably the vast majority of them—rested on basic misunderstandings about the nature and possible uses of mathematics. (Some critics seemed to assume that numbers are only good for counting. Other observers seemed to assume that all mathematical expressions amount to recipes for solving problems.) But some of the attacks on mathematical argument about evidence and inference harboured, even if not always distinctly, intuitions that seem to have considerable substance. One such intuition is that it makes little sense to ask people such as jurors to use a method of analysis or argument—such as Bayesianism—that is beyond their ‘common’, or ‘ordinary’, understanding.3 Another important intuition is that the nuances and complexities of real-world evidence and inference are too great to be captured by any type of formal analysis. Both of these intuitions involve assumptions about the cognitive capacities of human beings and the human brain. One reason I am interested in visualization of evidence and inference is that I suspect and hope that visualization of evidence and inference can make the logic of formal analytical
Therapeutic hypothermia is associated with a decrease in urine output in acute stroke patients

Abstract Aims It is unclear what effect therapeutic hypothermia may have on renal function, because its effect has so far been primarily evaluated in settings in which there may be possible confounding perturbations in cardiovascular and renal physiology, such deep intraoperative hypothermia, general anesthesia, and post-cardiac arrest. We sought to determine if therapeutic hypothermia affects renal function in awake patients with normal renal function who were enrolled into a clinical trial of hypothermia plus intravenous thrombolysis for acute ischemic stroke. Methods Eleven patients with normal renal function were cooled to 33°C for 24h using an endovascular catheter, and then re-warmed over 12h to 36.5°C, while hourly temperature, blood pressure, and fluid status data was recorded. Blood samples for blood urea nitrogen (BUN), creatinine, and hematocrit were drawn prior to treatment (baseline), immediately after hypothermia and re-warming (day 2), and again at day 7 or discharge, and values compared. Results On initiation of cooling, temperatures dropped from a median pre-treatment value of 36.1°C (IQR: 35.8–36.4°C) to 33.1°C (IQR: 33.1–33.4°C). Urine output decreased 5.1ml/h for every 1°C decrease in body temperature ( p -value=0.001), with no associated serious adverse events. There were no statistically significant changes in BUN, creatinine, or hematocrit in the hypothermia patients. Conclusion Inducing hypothermia in patients with relatively unperturbed renal physiology results in a decrease in urine output that is linearly correlated with the decrease in core temperature. This has important implications for fluid management in patients undergoing therapeutic hypothermia.
The senile epidermis: environmental influences on skin ageing and cutaneous carcinogenesis.

SUMMARY There is a wealth of new knowledge regarding mechanisms of carcinogenesis and their interaction with senescence and environmental insults, particularly on the effects of UV irradiation on the skin. Innovations and advances in tissue culture techniques now permit in vitro studies of keratinocytes and other benign and malignant skin-derived cells. The ageing processes and cutaneous neoplasia, therefore, can now be studied at the cellular level. New insights regarding the interrelationship of ageing, environment and cutaneous neoplasia are close at hand. Depletion in the number of Langerhans cells and suppression of their function in ageing and UV-exposed skin may allow tumour cells to overcome the host's defence system. The potential increase in UV irradiation due to depletion of the ozone layer may increase the incidence of skin tumours. Carcinogenesis involves three distinct steps: initiation, promotion, and malignant conversion. The mechanism has been studied in mice, where it is suggested the c-ras oncogene may play an important role.
Regional therapy of hepatic metastases

In conclusion, there are a variety of treatment approaches used by surgeons, interventional radiologists, and medical oncologists to treat metastatic cancer distributed throughout the liver. One conclusion is that the number of different techniques suggests that no single treatment has been uniformly successful to date. A second conclusion is that the number of techniques applied argues for the importance of this as a clinical problem in oncology today. The number of patients with metastatic disease to the liver and the potential for long-term survival if that disease can be controlled will lead to further combinations and refinements of these techniques in future clinical trials.
Vesicle involvement in the egg cortical reaction of the horseshoe crab, Limulus polyphemus L

Ultrastructural observations (TEM) of the cortical reaction in Limulus polyphemus have been difficult to obtain due to the relative impermeability of the transparent egg envelope to standard fixatives. With the application of trialdehyde fixation techniques [Kalt, M. R., and Tandler, B. (1971). J. Ultrastruct. Res. 36, 633–645], the cortical reaction has now been examined and the role of cortical vesicles has been determined. The size of these vesicles in uninseminated eggs is heterogeneous, with small vesicles (0.5 μm) being apposed to the plasmalemma and with large vesicles (4 μm) located in a lower layer of the egg cortex. The contents of the small vesicles are translucent under the electron beam. With the onset of egg activation these vesicles fuse with the overlying plasmalemma. The contents of the large vesicles appear electron dense and exhibit distinctly different morphologies. Shortly after insemination these large vesicles begin to enlarge by fusing together. By 9 min after insemination some enlarged vesicles fuse with the plasmalemma to form pits on the egg surface. The remaining enlarged vesicles continue to fuse with the plasmalemma until approximately 60 min after insemination when few vesicles are remaining.
Differential fertility in the United States 1980: continuity or change?

This paper considers how changes in womens sociocultural characteristics have influenced recent patterns of differential fertility in the US and whether the convergence of fertility differentials observed up to 1970 has continued. The data are drawn from the June 1980 US Current Population Survey which is a probability sample survey selected to represent the civilian non-institutionalized population living in households. The study population consists of 20621 ever-married White and Black women aged 25-44 a group for various reasons considered to have a high impact from the point of view of fertility behavior. Fertility to date and ever expected fertility are the dependent variables. The respondents were separated into age cohorts and differentiated by race. The data suggest that there has been no change in differential fertility in recent years: the 2 youngest cohorts (25-29 and 30-34 years) have similar expected fertilities that are lower than those of the older cohorts. Age at 1st birth length of 1st birth interval income and education were negatively associated with fertility among both older and younger women of both races. Differentials by race have narrowed slightly. When fertility expectations were examined the association of the independent variables with expected completed fertility was weaker among younger women indicating that there has been some convergence in expected fertility. Further narrowing of differentials in actual fertility depends on how successful the younger women are in preventing future unplanned births. If the present tendency towards surgical sterilization (among both races and groups above and below the poverty level) persists it will make it possible for more women to stay within their expected total fertility levels.
An analysis of sequential variables in Pavlovian conditioning employing extended and limited acquisition training

Abstract Sequential theory’s memory model of learning has been successfully applied in response contingent instrumental conditioning experiments ( Capaldi, 1966 , Capaldi, 1967 , Capaldi, 1994 , Capaldi and Miller, 2003 ). However, it has not been systematically tested in nonresponse contingent Pavlovian conditioning experiments. The present experiments attempted to determine if several sequential variables affect responding in Pavlovian situations as they do in instrumental ones. Of primary concern here were the effects on extinction of number of NR transitions (the number of times a nonreinforced trial is followed by a reinforced trial), N-length (the number of successive nonreinforced trials that precede a reinforced trial), and percentage of reinforcement (50 versus 100%) following either extended acquisition training (Experiment 1, 720 trials) or limited acquisition training (Experiment 3, 24 trials). In agreement with a sequential analysis, N-length increased resistance to extinction more than number of NR transitions following extensive training with the opposite occurring following limited training. In Experiment 1, greater resistance to extinction was associated with 50% than with 100% reinforcement, a partial reinforcement extinction effect (PREE). Experiment 2 examined an anomalous finding obtained in Experiment 1. A major theoretical difference between instrumental and Pavlovian conditioning has been held to be the greater ease of producing a PREE in instrumental than in Pavlovian conditioning ( Kimble, 1961 , Mackintosh, 1974 ). However, the findings obtained here suggest that the probability of obtaining a PREE and other Pavlovian extinction effects, as in instrumental conditioning, increases along with the effectiveness of the sequential variables employed.
An electronic and structural interpretation of tin oxide ELS spectra

Abstract In this study electron energy-loss spectroscopy (ELS) is used to examine polycrystalline tin oxide films which have been annealed, ion sputtered and oxygen treated. The major features in the N ( E ) loss spectrum are interpreted as due to collections of optically allowed interband transitions. It is demonstrated that depth profile information may be obtained by varying the primary electron beam energy. Combined ELS and valence-band XPS results indicate that a significant amount of structural information may be inferred from the size, shape and/or position of the N ( E ) ELS features. Core-level features are found to be quite sensitive to the presence of defects in an SnO 2 lattice with some specificity as to the type of defect.
Geochemical characteristics of different kinds of crude oils in the Tarim Basin, Northwest China

Based on the compositions and distributions of biomarkers in thirty-five representative oil samples, oils from the Tarim Basin of northwestern China are mainly divided into two oil families. One oil family contains relatively low amounts of C15-C20 isoprenoid hydrocarbons and shows pristane predominance with Pr/Ph ratios ranging from 1.50 to 3.00. The GC/MS analytical data of these oils show the occurrence of abundant hopanes, and low concentrations of steranes and tricyclic terpanes with hopanes/steranes ratios from 6.25 to 12.24 and tricyclic terpanes/hopanes ratios from 0.03 to 0.24. These oils contain low drimane relative to homodrimane (C15/C16 1.0), low hopanes/steranes ratios (0.65–2.50), high tricyclic terpanes/hopanes ratios (0.30–2.00) and a dominant peak at C23 in tricyclic tepanes, suggesting a marine organic origin. Oil-source rock correlation indicates that these two oil families seem to have been derived from Mesozoic Jurassic-Triassic terrestrial source rocks (shales and coal seams) and Lower Paleozoic Ordovician-Cambrian marine source rocks, respectively.
Pitch contour identification with combined place and temporal cues using cochlear implants

This study investigated the integration of place- and temporal-pitch cues in pitch contour identification (PCI), in which cochlear implant (CI) users were asked to judge the overall pitch-change direction of stimuli. Falling and rising pitch contours were created either by continuously steering current between adjacent electrodes (place pitch), by continuously changing amplitude modulation (AM) frequency (temporal pitch), or both. The percentage of rising responses was recorded as a function of current steering or AM frequency change, with single or combined pitch cues. A significant correlation was found between subjects' sensitivity to current steering and AM frequency change. The integration of place- and temporal-pitch cues was most effective when the two cues were similarly discriminable in isolation. Adding the other (place or temporal) pitch cues shifted the temporal- or place-pitch psychometric functions horizontally without changing the slopes. PCI was significantly better with consistent place- and temporal-pitch cues than with inconsistent cues. PCI with single cues and integration of pitch cues were similar on different electrodes. The results suggest that CI users effectively integrate place- and temporal-pitch cues in relative pitch perception tasks. Current steering and AM frequency change should be coordinated to better transmit dynamic pitch information to CI users.
Accuracy of Equations to Predict Basal Metabolic Rate in Older Women

Abstract Objective To assess the accuracy of several published equations for predicting basal metabolic rate (BMR) in older women. Design BMR was assessed in 116 healthy, older white women, aged 60 to 82 years, on three successive mornings by indirect calorimetry. Body composition was determined by dual energy X-ray absorptiometry or hydrostatic weighing. The measured BMRs were compared with values obtained from eight published prediction equations that used solely, or in various combinations, measures of height, weight, fat-free mass, age, and menopausal status. Statistical analyses performed The root mean squared prediction error (RMSPE) was used to determine how accurately predicted BMR matched actual BMR for each subject. In addition, regression analysis was used to evaluate accuracy of predicted BMR vs directly measured BMR. Results Predicted mean BMR determined using all eight equations was significantly correlated to measured BMR ( P =.0001), accounting for 30% to 52% of the variance of measured BMR. When analyzed by RMSPE, however, the equations of Owen et al (1986), Fredrix et al (1990), and Harris-Benedict (1919) predicted actual BMR for each subject within an average of 116kcal/day, and the equation of Cunningham (1980) resulted in the largest prediction error at 208kcal/day. Applications/conclusions The regression equations of Owen et al (1986), which used body weight, Fredrix et al (1990), which used body weight and age, and Harris-Benedict (1919), which used age, weight, and height as variables, were most accurate in predicting BMR in our sample of healthy older women. J Am Diet Assoc. 1995; 95:1387-1392 .
Inorganic analysis of excavated human bone after surface removal

Abstract In order to decrease the effects of contamination during burial, we have removed about 1 mm from the surfaces of 50 human femurs from the Gibson (Middle Woodland), Ledders (Late Woodland), and Helton (Emergent Mississippian) sites. Elemental analysis of these abraded samples was compared with analysis of unabraded samples from the same femurs. Surface removal reduced levels of contaminative elements such as Fe, Al, and Mn but had little or no effect on Ca, Sr, and Ba. Analysis of variance was altered by cleaning. Many apparent differences between the sexes disappeared and must have been due to differential contamination. Other differences based on sex, age, site, or time are retained, improved, or initially uncovered by surface cleaning.
Alterations in diastolic function in response to progressive left ventricular hypertrophy.

To examine the time course of the functional consequences of progressive left ventricular hypertrophy, diastolic left ventricular inflow and wall thinning variables were analyzed in 13 dogs before and 2, 4, 8 and 12 weeks after creation of perinephritic hypertension. Left ventricular echocardiograms were digitized for dimensions, mass and peak rates of wall thinning (-dh/dt/h) and cavity enlargement (dD/dt/D). Doppler recordings of left ventricular inflow were analyzed for peak early (E) and late (A) diastolic inflow velocities, their ratio and atrial filling fraction. At 2 weeks, systolic blood pressure increased from 151 to 233 mm Hg, wall stress from 52 to 80 kdynes/cm2and posterior wall thickness from 0.68 to 0.84 cm (all p < 0.05). Left ventricular mass increased from 90 to 115 g over 12 weeks (p < 0.05). Heart rate, cavity size and systolic shortening were unchanged at all data points. Diastolic abnormalities accompanied the developing hypertrophy and included impairment of early function, as demonstrated by a peak rate of wall thinning, from −13.4 to −8.9 Vs at 2 weeks (p < 0.05), increased dependence on atrial systolic filling, a decrease in E/A from 1.68 to 1.29 at 4 weeks (p < 0.05) and an increase in atrial filling fraction from 30% to 43% at 8 weeks (p = NS). Thus, diastolic dysfunction is an early consequence of experimental left ventricular hypertrophy. Different aspects of diastolic impairment are sensitively reflected by echocardiographic Doppler recordings, suggesting that these methods should be useful for the detection of diastolic dysfunction inhuman patients.
Biocultural considerations of food cravings and aversions: an introduction

Food is fundamental to our existence as humans, but assertions about the kinds of foods that are appealing or repulsive vary widely. This thematic issue deals with assessments of food as desirable, or not, in order to understand the complex reasons why some foods are strongly craved while others are avoided. To do this, the five articles in this issue situate food cravings and aversions bioculturally, in the contexts of our history as a species, in the landscape of cultural heritage, and in the individual life course. By exploring both the biological and cultural mechanisms that shape food preferences, we reveal the complex and important underpinnings of the critical endeavor of food selection.
Identification of molecular ferritin in homogenates and sections of rat liver.

Dense particles, approximately 55 A in diameter, were observed in fractions isolated by high-speed centrifugation from rat liver homogenates. These were identified as the iron-containing micelles of ferritin. Similar particles were observed in thin sections of intact liver cells. They increased greatly in number following the administration of iron to the animals.
Conformational changes in von Willebrand's factor protein: Effects on the binding of factor VIII‐coagulant

The effects of conformational changes in purified canine von Willebrand's factor (VWF) were investigated to explore the relationship between its factor VIII-related antigen (VIII:AG) and ristocetin cofactor (RCoF) properties and the factor VIII-coagulant (VIII:C) binding site(s). Binding of VIII:C from canine von Willebrand's disease (VWD) plasma by VWF was used to measure the combining reaction of these proteins. The VWF was denatured to varying degrees by exposure to temperature and pH extremes, low ionic strength, and 6 M urea. Various treatments resulted in three types of change: elimination of RCoF, VIIIR:Ag, and VIII:C binding, removal of RCoF activity alone; or elimination of RCoF and retarded elution of VIII:Ag and VIII:C. As long as VIIIR:Ag reactivity was maintained, binding of VIII:C could be demonstrated; but in the absence of VIIIR:Ag, neither RCoF activity nor VIII:C binding remained. These results suggest that VIII:C binding and RCoF sites are separate on VWF and that interaction between VIII:C and VWF is possible even after significant structural changes occur in VWF. Furthermore, RCoF is more vulnerable to denaturation than the antigenic site. The spectrum of conformational changes that affect the properties of VWF may parallel the various recognized subtypes of VWD.
Nitrogen Assimilation Traits and Dinitrogen Fixation in Soybean and Common Bean

Nitrogen derived from symbiotic and mineral sources by a legume is determined by the interactions between mineral N supply, plant N demand, and N assimilation traits. These interactions need to be understood to maximize legume N2 fixation and yield, and to identify plant traits supporting high N2-fixation. These interactions were examined in inoculated soybean [Glycine max Merr. (L.)] and common bean (Phaseolus vulgaris L.) by varying N supply (9, 120, and 900 kg N ha-1) at two field sites. Nitrogen fixation was measured by 15N dilution method. Plants were sampled at full bloom (R2), 21 to 25 d from R2, and physiological maturity (R7). Total N of both legumes at R7 was 25% greater with 900 than 9 kg N ha(-1). With 900 kg N ha(-1), soybean N accumulation at R7 (271 kg N ha-1) was 42% more than common bean but was 22% less at R2 (78 kg N ha-1). Applied N had the largest impact on N accumulation rates before R2 and from the second sampling to R7, both periods of minimal N2 fixation. Rate of N accumulation by common bean (0.19 g N m(-2) d-1) was more uniform over the growth cycle than by soybean (0.26 g N m(-2) d-1) which peaked (0.58 g N m(-2)d-1) between R2 and the second sampling. This peak also coincided with maximum N2 fixation rate. Our 15N uptake and extractable soil N data indicate that common bean derived more N from the mineral source than soybean because of more efficient uptake. Greenhouse data indicated greater root weight and uptake of mineral N per unit root weight for common bean than soybean. Maximizing both N2 fixation and yield might entail timing the mineral N supply during early vegetative and late reproductive phases. The limited N2 fixation capacity of common bean might be due to N assimilation traits favoring mineral N uptake.