cssi/SciSciGPT-SciSciNet huggingface dataset:
Ethylene Polymerization Using Tetramethyl(2-methylthioethyl)cyclopentadienyl Complexes of Cobalt

Tetramethyl(2-methylthioethyl)cyclopentadiene complexes of cobalt have been synthesized and tested in ethylene polymerization. In combination with MMAO-3A, tetramethyl(2-methylthioethyl)cyclopentadienylcobalt diiodide (4) was shown to polymerize ethylene to linear polyethylene with Mn's in the range of 5000−68 000. The activity of the catalyst is improved compared to the previously described catalysts containing the Cp*Co+(PR3) unit. Cationic (tetramethyl(2-methylthioethyl)cyclopentadienyl)methylcobalt nitrile complexes 8 were also shown to be competent ethylene polymerization catalysts, producing polyethylene with similar properties as observed with 4/MMAO-3A.
Photoproducts from 4-thiouracil and cytosine and from 4-thiouridine and cytidine: refinement of tertiary tRNA structure.

Summary The photoreaction at 335 nm between 4-thiouracil and cytosine at 4° in aqueous solution leads, inter alia , to 5-(4′-pyrimidin-2′-one)cytosine (Ia), and between 4-thiouridine and cytidine, to 5-(1'-β-D-ribofuranossyl-4'-pyrimidin-2'-one)cytidine (Ib). The latter represents the structure produced when the 4-thiouridine at position 8 and the cytidine at position 13 combine during the irradiation of various E. coli tRNA's at 335 nm. These bases in the tRNA must be close together and oriented geometrically so that a thietane (IIb) and ultimately covalently-linked Ib can be formed readily.
Prejudice and the Estelusti: A Qualitative Examination of Contemporary Status

This article examines how prejudice has resulted in the attenuated status position of the Estelusti (Black Seminoles) vis-a-vis the Seminole Indians within the Seminole Nation of Oklahoma. I argue that the most succinct status precipitators: allotment, statehood, Jim Crow (legalized segregation), money, and overt attempts at disenfranchisement can be discerned using Bobo’s (J Soc Issues, 55:445–472, 1999) association of prejudice as group position theory. Drawing from a purposive sample of self-identified Estelusti, I delineate the social and historical factors relevant to the group position of the Estelusti. Additionally, three themes emerge from socio-historical examination: (1) a shifting relationship characterized as either congenial or antagonistic depending on the socio-historical period; (2) the source of intergroup antagonism rooted in outside forces; and (3) a lack of knowledge of the role of slavery (on both sides) as a catalyst for conflict between the two groups.
Observations on the senescence of cells derived from articular cartilage

Abstract In the experiments described here, we have sought to determine whether primary cultures of cells derived from articular cartilage will, upon subsequent subculture, undergo in vitro senescence in a manner analogous to that described for several other types of diploid cell. Using cells from the articular cartilage of rabbits, dogs and man, we have established that the population doubling capacity of cultures of these cells is directly related to the specific lifespan of the donor organism. Furthermore, the doubling capacity of the initial cultures of lapine articular chondrocytes is inversely related to the age of the donor rabbit. By these criteria, serially passaged primary cultures of cells derived from articular cartilage appear, a priori , to be a valid system for studies of cellular ageing. Monolayer cultures of lapine chondrocytes appear to “dedifferentiate” after several passages. However, the same cells can be grown as clones, under which conditions they appear to retain better their differentiated properties. Even under these circumstances, lapine articular chondrocytes have a limited capacity for growth, which can be calculated to approximate to the same average number of cell divisions as undergone by monolayer cultures. Lapine chondrocytes frequently transform into established lines of fibroblastic cells. Transformation of canine chondrocytes was more rare, while human chondrocytes have not been observed to transform. This suggests that resistance to transformation is somehow related to lifespan. In addition to furthering our understanding of cellular ageing, studies of the senescence of articular chondrocytes could provide new insights into the aetiology of primary osteoarthritis.
First Results from the Amy Detector at Tristan

Bhabha scattering and multi-hadronic e+e− annihilation events have been observed in the AMY detector at √s=500 GeV at the TRISTAN e+e− storage ring. Here we report the results of a preliminary analysis of the properties of these events. Of particular note is one event that contains a high energy, isolated gamma ray together with a large amount of missing momentum that penetrates the fiducial volume of the detector.
The Effect of Insecticidal Soil Drenches on the Growth of Young Cabbage and Muskmelon Plants

Soil drenches of insecticidal emulsions are commonly used by commercial growers in Indiana in transplanting cabbage and related cruciferous crops for the control of the cabbage maggot, Hylemyia brassicae (Bouche), and occasionally for the control of cutworms around hills of melons. Investigations were made on young cabbage and muskmelon plants grown in the greenhouse to determine the chemicals in the formulations which at certain dilutions have caused retardation of plant growth and even death of plants under field conditions. Emulsion formulations of six insecticides—aldrin, chlordane, dieldrin, endrin, heptachlor and lindane—and emulsion formulations of their respective solvent-emulsifiers were tested at six dilutions on cabbage and 18 dilutions on muskmelon plants. Results based on the number and weight of surviving plants indicated that muskmelon plants were more sensitive to the drenches than cabbage plants and that in general the solvent-emulsifier formulations were more toxic than their respective complete emulsion. Of the six materials tested, formulations of aldrin and chlordane were less toxic to young cabbage and muskmelon plants than formulations of dieldrin, endrin and heptachlor, which in turn were less toxic than the lindane formulations.
Status of the state of undernutrition and environmental influences for disease in later generations.

This coming generation may be the first of subsequent generations sicker than their parents. Children asyoungassevenyearsoldarepresenting with advanced disease processespreviously seen in adulthood. The incidence of childhood obesity in the United States has more than tripled since 1980, but this has become a worldwide issue. Even though many children eat enough to fend off hunger, some do not get the nutrients they need for growth and development. Women and children commonly make up the most vulnerable segment of societies
Unmarried Left Ventricular Assist Device (LVAD) Recipients Are More Likely To Experience Adverse Events

Purpose Candidates for LVAD have varying degrees of social support. The effect of marital status (MS) on outcomes in these patients is unknown. We hypothesized that being married is associated with less risk of adverse events. Methods and Materials 151 consecutive Heartmate II LVAD implants at our center surviving index hospitalization were reviewed for MS at time of implant, implant date, strategy (DT vs BTT), IMACS class, age, race, and sex. A subset of 89 patient had full INTERMACS followup event data. Cox proportional hazards model for time to death, any event, and individual events was performed, censoring for transplant and adjusting for age, IMACS class, and strategy. Results 66.2% of patients were married. Married patients had lesser hazard for mortality, any event, and each component event. After adjustment this effect was significant for mortality, rehospitalization, infection, and neurologic events. At 12 months, 19.6% of unmarried vs 8% of married patients had died (p =0.04). [ figure 1 ] Conclusions Unmarried LVAD recipients are at greater risk of adverse events after the index hospitalization. This likely reflects the social support advantages of marriage. In unmarried patients, other means of social support should be closely assessed. Hazard Ratio - Married vs Unmarried Event Unadjusted HR (95% CI) Adjusted HR * (95% CI) Death† 0.61 (0.34-1.10) 0.47 (0.23-0.93) Any Even ♦ 0.49 (0.29-0.84) 0.58 (0.32-1.05) Rehospitalization ♦ 0.45 (0.26-0.78) 0.52 (0.28-0.96) Infection ♦ 0.37 (0.19-0.74) 0.44 (0.21-0.90) Neurologic Event ♦ 0.06 (0.01-0.48) 0.05 (0.01-0.61) Bleeding ♦ 0.57 (0.15-2.12) 0.61 (0.15-2.52) Device Failure ♦ 0.30 (0.07-1.36) 0.38 (0.10-2.44) * Adjusted for Age, IMACS class, Strategy †N=151 survivors of index hosp. ♦ N=89 subset with INTERMACS all-events data
Chronic Medical Conditions among Jail Detainees in Residential Psychiatric Treatment: A Latent Class Analysis

Studies of incarcerates with serious mental illnesses have found elevated rates of chronic medical conditions such as asthma and diabetes, and of infectious diseases such as tuberculosis compared with general population rates. This study explored the pattern of chronic medical conditions in a sample of adult detainees in psychiatric treatment in a large urban jail to develop a clinical profile encompassing the full range of medical conditions. A total of 431 male and female detainees were sampled with certainty from admissions to a residential psychiatric treatment program (overall recruitment rate = 67%). Interviews used the World Mental Health version of the Composite International Diagnostic Interview to assess psychiatric and substance use disorders per DSM-IV criteria and chronic medical conditions. Latent class analysis was conducted using 17 medical conditions as class indicators, yielding a 3-class model composed of: a latent class with a high to intermediate probability of multiple medical conditions (HMC; 12.5% of the sample); an intermediate class with a lower probability of having a smaller number of medical conditions (MMC; 43.2%); and a class with a low probability of any medical condition (44.3%). Those in the HMC class were more likely to report respiratory problems, severe headaches, musculoskeletal pain, hypertension, and arthritis, have greater functional impairment, and have a higher number of co-occurring psychiatric disorders. Being older (50+ years) and female were associated with higher odds of being in the HMC or MMC classes. The policy implications for providing medical care to incarcerates with complex mixtures of medical conditions and psychiatric disorders are considered.
Effect of tip vortex structure on helicopter noise due to blade-vortex interaction

A potential cause of helicopter impulsive noise, commonly called blade slap, is the unsteady lift fluctuation on a rotor blade due to interaction with the vortex trailed from another blade. The relationship between vortex structure and the intensity of the acoustic signal is investigated. The analysis is based on a theoretical model for blade/vortex interaction. Unsteady lift on the blades due to blade/vortex interaction is calculated using linear unsteady aerodynamic theory, and expressions are derived for the directivity, frequency spectrum, and transient signal of the radiated noise. An inviscid rollup model is used to calculate the velocity profile in the trailing vortex from the spanwise distribution of blade tip loading. A few cases of tip loading are investigated, and numerical results are presented for the unsteady lift and acoustic signal due to blade/vortex interaction. The intensity of the acoustic signal is shown to be quite sensitive to changes in tip vortex structure.
TGF‐β1 induces the expression of type I collagen and SPARC, and enhances contraction of collagen gels, by fibroblasts from young and aged donors

Fibroblasts have a major role in the synthesis and reorganization of extracellular matrix that occur during wound repair. An impaired biosynthetic or functional response of these cells to stimulation by growth factors might contribute to the delayed wound healing noted in aging. We, therefore, compared the responses of dermal fibroblasts from young and elderly individuals (26, 29, 65, 89, 90, and 92 years of age) to transforming growth factor-beta 1 (TGF-beta 1) with respect to: (1) the synthesis of type I collagen and SPARC (two extracellular matrix proteins that are highly expressed by dermal fibroblasts during the remodeling phase of wound repair) and (2) the contraction of collagen gels, and in vitro assay of wound contraction. With the exception of one young donor, all cultures exposed for 44 hours to 10 ng/ml TGF-beta 1 exhibited a 1.6- to 5.5-fold increase in the levels of secreted type I collagen and SPARC, relative to untreated cultures, and exhibited a 2.0- to 6.2-fold increase in the amounts of the corresponding mRNAs. Moreover, the dose-response to TGF-beta 1 (0.1-10 ng/ml), as determined by synthesis of type I collagen and SPARC mRNA, was as vigorous in cells from aged donors as in cells from a young donor. In assays of collagen gel contraction, fibroblasts from all donors were stimulated to a similar degree by 10 ng/ml TGF-beta 1. In conclusion, cells from both young and aged donors exhibited similar biosynthetic and contractile properties with exposure to TGF-beta 1. It therefore appears that the impaired wound healing noted in the aged does not result from a failure of their dermal fibroblasts to respond to this cytokine.
Mitochondrial dysfunction in bipolar disorder: evidence from magnetic resonance spectroscopy research.

Magnetic resonance spectroscopy (MRS) affords a noninvasive window on in vivo brain chemistry and, as such, provides a unique opportunity to gain insight into the biochemical pathology of bipolar disorder. Studies utilizing proton (1H) MRS have identified changes in cerebral concentrations of N-acetyl aspartate, glutamate/glutamine, choline-containing compounds, myo-inositol, and lactate in bipolar subjects compared to normal controls, while studies using phosphorus (31P) MRS have examined additional alterations in levels of phosphocreatine, phosphomonoesters, and intracellular pH. We hypothesize that the majority of MRS findings in bipolar subjects can be fit into a more cohesive bioenergetic and neurochemical model of bipolar illness that is both novel and yet in concordance with findings from complementary methodological approaches. In this review, we propose a hypothesis of mitochondrial dysfunction in bipolar disorder that involves impaired oxidative phosphorylation, a resultant shift toward glycolytic energy production, a decrease in total energy production and/or substrate availability, and altered phospholipid metabolism.
Mesenchymal chondrosarcoma of the orbit. Report of three new cases and review of the literature.

Background: Extraskeletal mesenchymal chondrosarcoma is a rare tumor characterized by undifferentiated mesenchymal cells with islands of mature hyaline cartilage. Considering all sites, long-term survival is approximately 30%. Only seven cases of orbital mesenchymal chondrosarcoma have been reported. Methods: The records of three cases of orbital mesenchymal chondrosarcoma treated at the Columbia-Presbyterian Medical Center, and the seven previously reported cases of this tumor were reviewed to determine clinical characteristics and appropriate therapy. Results: Nine of the 10 patients were female; age of onset ranged from 10 to 35 years. Of eight patients with at least 2 years of observation, five survived 5 or more years after resection, or after resection plus adjuvant therapy. Two patients died of metastatic disease 2 and 5 years, respectively, after the initial treatment, and one died of pneumonia 6 months after surgery. Review of the histology of the three cases treated at Columbia-Presbyterian Medical Center did not identify distinct histologic types that might guide therapy. Presenting symptoms were typical of symptoms of an orbital mass: proptosis, pain, diplopia, change in visual acuity, ptosis, and tearing. Conclusion: The small number of reported cases of mesenchymal chondrosarcoma of the orbit prevents definitive conclusions, but it appears that resection is adequate therapy in some cases. Extraskeletal mesenchymal chondrosarcoma of the orbit may have a better prognosis than tumors in other sites.
Prediction of Greenhouse Warming by a Coupled Ocean-Atmosphere Model

This paper describes the response of a coupled ocean-atmosphere-land surface model developed at GFDL to gradual changes of atmospheric carbon dioxide. It summarizes the results in three recently published papers (Stouffer et al., 1989 Manabe et al., 1991, 1992). They represent the current state of the art in predicting further climate change induced by greenhouse gases in the atmosphere.The warming of the coupled system is reduced by the effective thermal inertia of the earth's surface which is essentially controlled by the vertical mixing of heat in the oceans. This study investigates how such vertical mixing of heat is achieved, resulting in the delay of the greenhouse warming in the joint troposphere-continental surface-ocean system.
Reconstruction of Longitudinal Beam Profiies from Nondestructive Electromagnetic Probes

The Fusion Materials Irradiation Test (FMIT) 2-MeV accelerator has nondestructive diagnostic probes that sense changes in the electromagnetic fields of the bunched beam. These probes accurately perform their primary functions, but do not have well-behaved, frequency-domain characteristics from which the longitudinal beam profile can be measured using convolution-integral processing techniques. Therefore, each of the probes transfer function was determined using a tightly bunched electron beam as a source for impulse response tests. Using the Signal Processing Analyzer (SPA) code, output signals from these probes mounted on the FMIT beamline were deconvolved with sampled impulse response data to produce a longitudinal electromagnetic field distribution of a beam bunch. With SPA's signal-processing techniques, any electromagnetic probe shorter than s? and having significant signal-to-noise ratios can reconstruct longitudinal profiles, provided the probe's transfer function is known.
An architecture for graphics processing in an FPGA (abstract only)

Graphics processing is most often accomplished in standalone ASICs that were originally designed for gaming applications. The graphics processors produce visually appealing functionality based upon 3D rendering algorithms, but they can also require large amounts of power and typically have only short-term device availability. This paper proposes a novel architecture for graphics processing in an FPGA that is motivated by industrial applications that require low power, high reliability, low cost, and long-term device availability. Due to resource constraints and architectural constructs, many traditional graphics processing concepts do not translate well to FPGAs; hence, a graphics processing architecture crafted specifically for FPGAs is needed. The proposed architecture provides a high degree of scalability and flexibility to allow customization for unique applications, and it also features the migration of technology that previously has been used only for packet processing. The unique multi-threaded packet processing engine accelerates the line rasterization with a careful partitioning of the processing across software and hardware. The baseline architecture, which can be scaled for higher performance through parallelisms, will be capable of rasterizing over 50 million pixels per second -- more than enough for any application with XGA resolution. Future work will focus on the complete implementation and optimization of the architecture as well as an extension to support general-purpose computations (GPGPU) on the FPGA-based graphics processor.
The influence of composition and process parameters on the microstructure of TiC-Fe multiphase and multilayer coatings

Abstract Composite TiC-Fe coatings obtained by the plasma spray synthesis process can be composed of alternate TiC-rich and TiC-poor lamellae of different hardnesses. This study was undertaken to assess the influence of the fabrication parameters on the microstructure of these coatings. Both the composition of the micropellets, which lead to the synthesis and dispersion of fine crystals within the iron matrix upon spraying, and the spraying parameters were examined. Among all the variables considered it was found that the parameters related to the fabrication of micropellets, such as their size and their expected TiC volume content, and those related to the solidification of synthesized products are the main factors affecting the hardness of TiC-rich layers. Coatings obtained by spraying micropellets comprising TiC and iron powders agglomerated together are composed of large angular and hard TiC particles embedded in a matrix whose hardness is between 300 and 500 kgf mm-2. In contrast, plasma-spray-synthesized coatings are composed of alternate soft and hard layers whose hardness varies according to the fabrication parameters and is between 1000 and 1800 kgf mm-2 for hard layers and between 300 and 600 kgf mm-2 for soft ones. These plasma-spray-synthesized TiC-Fe coatings, because of their multilayer and fine-grained multiphase microstructure, are expected to be more resistant to crack propagation and, consequently, to wear.
The Complex Interaction Between Methamphetamine Abuse and HIV-1 Pathogenesis.

The global HIV/AIDS pandemic has claimed the lives of an estimated 35 million people. A significant barrier for combating this global pandemic is substance use since it is associated with HIV transmission, delayed diagnosis/initiation of therapy, and poor adherence to therapy. Clinical studies also suggest a link between substance use and HIV-disease progression/AIDS-associated mortality. Methamphetamine (METH) use is one of the fastest-growing substance use problems in the world. METH use enhances high-risk sexual behaviors, therefore increases the likelihood of HIV-1 acquisition. METH use is also associated with higher viral loads, immune dysfunction, and antiretroviral resistance. Moreover, METH use has also been correlated with rapid progression to AIDS. However, direct effects of METH on HIV-1 disease progression remains poorly understood because use of METH and other illicit drugs is often associated with reduced/non adherence to ART. Nevertheless, in vitro studies demonstrate that METH increases HIV-1 replication in cell cultures and animal models. Thus, it has been proposed that METH’s potentiating effects on HIV-1 replication may in part contribute to the worsening of HIV-1 pathogenesis. However, our recent data demonstrate that METH at physiologically relevant concentrations has no effect and at higher concentrations inhibits HIV-1 replication in CD4+ T cells. Thus, the goal of this review is to systematically examine the published literature to better understand the complex interaction between METH abuse and HIV-1 disease progression.
Control Charting: Process Improvement over Theoretical Elegance

This article describes two issues that are truly at the heart of all control chart applications; namely, sampling strategy and development of initial limits prior to the achievement of process control. The development of a strategy which achieves proces..
Cell outgrowth from the human ACL in vitro: regional variation and response to TGF-β1

One of the new methods being developed to stimulate healing of the human anterior cruciate ligament (ACL) after rupture is the implantation of a biodegradable scaffold which the host cells invade, populate and remodel. One of the cellular behaviors critical to the success of this method is cell outgrowth from the ligament remnants onto an adjacent scaffold. As morphological differences have been previously reported in the proximal and distal human ACL, the primary aim of this study was to determine if the cells from the proximal and distal ACL had different outgrowth behaviors as well. A second aim was to determine whether TGF-beta1, reported to be a mitogen for fibroblasts, would affect the outgrowth behaviors from the proximal and distal ACL. To achieve these aims, explants from both the proximal and distal human ACL were placed into culture under various conditions and outgrowth measured for 42 days. In explants cultured with 10% fetal bovine serum (high serum group) the explants from the proximal ACL had an earlier start of outgrowth than the distal explants (p < 0.015), and outgrowth rates were similar in the two groups. In explants cultured with 2% fetal bovine serum (low serum group), the explants from the proximal ACL had an earlier start to outgrowth (p < 0.003) as well as a faster rate of outgrowth (p < 0.004) than the distal explants. The addition of TGF-beta1 to the low serum cultures significantly slowed the rate of outgrowth from both groups of ACL explants (p < 0.025). These results suggest that outgrowth behaviors are different in the proximal and distal human ACL, and that TGB-beta1 has an inhibitory effect on cell outgrowth from ACL explants. However, this study is only a first step, and additional experiments are needed to further optimize tissue engineering parameters for enhancement of the repair of the ACL.
Simultaneous transgenic suppression of LePG and LeExp1 influences fruit texture and juice viscosity in a fresh market tomato variety.

Tomatoes are grown for fresh consumption or for processing of the fruit. Some ripening-associated processes of the fruit can either contribute to or degrade attributes associated with both fresh and processing quality. For example, cell wall disassembly is associated with loss of fresh fruit firmness as well as with loss of processed tomato product viscosity. Several enzymes contribute to cell wall polysaccharide disassembly. Polygalacturonase (PG, poly[1,4-α-d-galactouronide] glucanohydrolase, EC 3.2.1.15) is among the most abundant polysaccharide hydrolases in ripening tomato fruit and is the major contributor to pectin depolymerization. Expansin (LeExp1) is also abundant in ripening fruit and is proposed to contribute to cell wall disassembly by nonhydrolytic activity, possibly by increasing substrate accessibility to other enzymes. Suppression of either LePG or LeExp1 expression alone results in altered softening and/or shelf life characteristics. To test whether simultaneous suppression of both LePG ...
Chips, infections, and national security.

The recent outbreaks of anthrax in the United States have brought a new urgency to the diagnosis of infectious disease resulting from bioterrorism. At the early stage of infection, pulmonary anthrax mimics viral upper respiratory infections; it is only later in the disease, often when the pathology
Gender earnings inequality in the service and manufacturing industries in the U.S.

This paper compares earnings inequality between women and men in a growing sector of the U.S. economy – the service sector, and a shrinking sector – manufacturing. We examine the hypothesis that deindustrialization will reduce inequality, and find that the absolute magnitude of the gender earnings gap is, in fact, smaller in the service sector. Decomposition analysis is used to partition the gender earnings gap into three parts: (1) earnings differences due to differences in mean characteristics – such as education and experience; (2) earnings differences due to preferential treatment of men; and (3) earnings differences due to disadvantageous treatment of women. The latter two constitute estimates of gender discrimination. The results of this study suggest that, ceteris paribus, deirndustrialization will likely reduce the gender gap in hourly earnings. However, this will come at the cost of lower earnings for both males and females, with the drop in earnings being particularly large for males. While dein...
IN THE FRATERNAL SISTERHOOD Sororities as Gender Strategy

This article analyzes sororities as gender strategy. The author argues that young women use sororities as a strategy for dealing with the complexities of gender(ed) relations—both among women and between women and men. Based on a case study of a nationally affiliated historically white sorority, the article focuses primarily on how sororities structure relationships among women and between women and men, helping them to navigate campus life, particularly what Holland and Eisenhart have identified as a male-dominated culture of romance. Employing a language of sisterhood, sororities encourage strong bonds between members; still, they fail to resolve tensions between the collective interests of the sororities and the individualistic strategies of members in the romantic marketplace. It is argued that, while sororities can be seen as a collective response to male domination, they are not a challenge to it.
Zinc(II)-mediated enhancement of the agonist activity of histidine-substituted parathyroid hormone(1–14) analogues

Abstract Previous studies on parathyroid hormone (PTH)(1–14) revealed that residues (1–9) played a dominant role in stimulating PTH-1 receptor-mediated increases in cAMP formation. In the present study, we examined the effects of installing a metal-binding motif in the (10–14) region of rat PTH(1–14) on the peptide’s agonist activity. We found that substitution of histidine for the native asparagine at position 10 of PTH(1–14) provided a peptide that was approx. 8-fold more potent as an agonist in the presence of divalent zinc salts than it was in the absence of the metal. This enhancement in potency was dependent on the native histidine at position 14, the concentration of Zn(II) utilized, and did not occur with other divalent metal ions. The zinc-activated [His 10 ]-PTH(1–14) peptide was blocked by a classical PTH-1 receptor antagonist, PTHrP(7–36), and did not activate the PTH-2 receptor. The zinc-mediated enhancing effect did not require the large N-terminal extracellular domain of the PTH-1 receptor. Although we were able to demonstrate that [His 10 ]-PTH(1–14) binds Zn(II) using 1 H-NMR, our spectroscopic studies (circular dichroism and nuclear magnetic resonance) were not consistent with the notion that zinc enhanced the activity of [His 10 ]-PTH(1–14) simply by inducing a helical structure in the 10–14 region. Rather, the data suggest that the enhancement in cAMP potency arises from the formation of a ternary complex between [His 10 ]-PTH(1–14), a zinc atom, and the extracellular loop/transmembrane domain region of the PTH-1 receptor.
The complementarity of apparent and real motion.

It is proposed that apparent motion does not parallel real motion. Bather, apparent motion occurs when the off-period is equivalent to angular velocities at which an object in real motion appears blurred. Experimental evidence is reported which supports this view. It suggests that apparent motion serves biologically to extend the range of motion perception beyond that allowed by time-constants early in the visual system.
Factors Affecting Alcohol Consumption in Black Women. Part II

An eight-variable model for understanding and predicting alcohol consumption in a sample of 289 African American women is evaluated using a structural equation methodology. We found that life events, physical health problems, and internalized racialism played important roles in accounting for variance in alcohol consumption. Marital status did not have the predicted inverse effect on alcohol consumption. While religious orientation did not have the expected inverse effect on alcohol consumption, it had an unexpected direct effect on internalized racialism, which had a direct effect on alcohol consumption. We found that the effects of socioeconomic status and developmental status on alcohol consumption were mediated through other variables specified in the model. Overall the model, which provided partial to complete support for five of eight hypotheses, provided a statistically adequate fit.
The profitization of health promotion.

In this article the author argues that not only is the marketplace an ineffective arena for health development, it is currently generating decision-making paths that obscure more effective perspectives and directions to promote Americans' health. To illustrate this premise, available evidence is presented that suggests that the use of “health promotion” by the proprietary sector, as well as the commercialization of health promotion, is creating decision-making processes that are not accountable to those whom they affect. This emerging infrastructure is characterized by organizations, programs, delivery channels, and evaluative criteria that do not give people's health priority over organizational interests. These developments require critical examination and work on alternatives if the promotion of health is to result in more health than hype.
Psychosocial factors impair vascular responses of coronary arteries.

BACKGROUNDFour sets of monkeys were used to examine the effect of chronic psychosocial disruption and diet on dilator responses of coronary arteries.METHODS AND RESULTSOne set consisted of monkeys consuming monkey chow and living in a stable social setting (nonatherosclerotic controls, n = 6). Three sets consumed an atherogenic diet for 14 months followed by one of three treatments for the next 16 months: 1) a high-cholesterol diet and housed in unstable social groups (n = 9); 2) a low-cholesterol diet and housed in unstable (n = 8); or 3) stable groups (n = 10). Quantitative coronary angiography revealed that intracoronary infusion of acetylcholine resulted in a change of diameter (versus infusion of 5% dextrose in water) of +4 +/- 1% in control monkeys and -11 +/- 4% in unstable monkeys consuming a high-cholesterol diet (p less than 0.05). In monkeys consuming the cholesterol-lowering diet, the change in artery diameter was +2 +/- 4% in stable and -10 +/- 4% in unstable social conditions (p less than 0....
General analysis of the mechanical efficiency of reciprocating heat engines

Abstract This paper examines the mechanical efficiency of reciprocating heat engines in a general setting. From an abstract mathematical characterization of machines, the relation of the pressure-volume cycle of an engine and the characteristics of its mechanism to its useful work output is established. Using the ideal Stirling engine in conjunction with this relation, a functional upper bound on the mechanical efficiency of all engines is derived. This shows the existence of limits on compression ratio under conditions relating the level of performance of the mechanism to the ratio of engine operating temperatures. This has implications for the design of engines intended for operation from low grade sources, such as industrial waste heat or passive solar energy.
Decentralized control of a class of distributed systems

Many large scale mechanical systems can be modeled in terms of partial differential equations which can then be discretized to give what may be termed "homogeneous interconnected systems" or "cellular structures". In this paper we consider a class of such systems and the relation between performance and information transfer.
Association Between Honey Consumption and Infant Botulism

Infant botulism, a disease that results in a blockade of voluntary motor and autonomic functions, was first recognized in the United States in the late 1970s. Since then, more than 1000 cases in this country have been reported to the Centers for Disease Control and Prevention (CDC). Numerous studies have shown that the ingestion of honey is linked with infant botulism. In addition, honey samples across the United States have tested positive for Clostridium botulinum spores and toxins. Such substantial evidence led the CDC to recommend that honey not be given to infants younger than 12 months old. It is important that clinicians be familiar with this risk and should not recommend honey-containing products or supplements or the use of honey as a flavoring agent for infants in this age group.
Breakfast is the Lowest Fat Meal for Young Adult Women

Abstract Breakfast consumption and the contribution of breakfast foods to the daily fat and fiber intakes of young adults were evaluated in a sample of 2628 young adults (mean ± SD age = 19.6 ± 3.0 years).The subjects (males = 817, females = 1811) completed 24-hour dietary records for a college introductory nutrition class. The 1-day dietary intake data were analyzed for the following: (1) differences in daily fat and fiber intake between breakfast eaters (80%) and skippers (20%) by gender; (2) fat and fiber content of breakfast compared to other meals; and (3) foods most frequently consumed for breakfast by gender. More women who ate breakfast had daily fat intakes ≤30% energy from fat compared to the women who skipped breakfast (40% vs. 28%, p
Statistically stored, geometrically necessary and grain boundary dislocation densities: microstructural representation and modelling

A unified physically based microstructural representation of f.c.c. crystalline materials has been developed and implemented to investigate the microstructural behaviour of f.c.c. crystalline aggregates under inelastic deformations. The proposed framework is based on coupling a multiple-slip crystal plasticity formulation to three distinct dislocation densities, which pertain to statistically stored dislocations (SSDs), geometrically necessary dislocations (GNDs) and grain boundary dislocations. This interrelated dislocation density formulation is then coupled to a specialized finite element framework to study the evolving heterogeneous microstructure and the localized phenomena that can contribute to failure initiation as a function of inelastic crystalline deformation. The GND densities are used to understand where crystallographic, non-crystallographic and cellular microstructures form and the nature of their dislocation composition. The SSD densities are formulated to represent dislocation cell microstructures to obtain predictions related to the inhomogeneous distribution of SSDs. The effects of the lattice misorientations at the grain boundaries (GBs) have been included by accounting for the densities of the misfit dislocations at the GBs that accommodate these misorientations. By directly accounting for the misfit dislocations, the strength of the boundary regions can be more accurately represented to account for phenomena associated with the effects of the GB strength on intergranular deformation heterogeneities, stress localization and the nucleation of failure surfaces at critical regions, such as triple junctions.
Petrologic Intervals and Petrofacies in the Great Valley Sequence, Sacramento Valley, California

The Great Valley Sequence of Upper Jurassic to Upper Cretaceous strata is composed of clastic detritus eroded from the Sierran-Klamath belt, which was the site of a late Mesozoic magmatic arc. The sequence accumulated mainly as a prismatic wedge of turbidites in an asymmetric trough within the arc-trench gap. Stratigraphic variations in detrital sandstone mineralogy define five petrologic intervals, or nearly synchronous petrofacies, useful for regional correlation. By contrast, local lithofacies are markedly lenticular. The clastic debris in the sequence was derived mainly from volcanic and plutonic rocks in varying proportions. The parameters used to define the petrofacies include: (a) content of quartzose grains (Q), feldspar grains (F), and unstable lithic fragments (L) expressed as volumetric percentages of the Q-F-L population; (b) ratios of plagioclase to total feldspar (P/F) and volcanic rock fragments to total unstable lithic fragments (V/L), and (c) content of mica (M) expressed as volumetric percentage of framework sand grains. The most distinctive characteristics of the petrofacies recognized, and their approximate time-stratigraphic spans, are as follows: (1) Stony Creek (Tithonian-Neocomian): quartz-poor and feldspatholithic sandstones with high P/F, high V/L, low M; (2) Lodoga (Aptian-Albian): quartz-rich sandstones with high P/F; (3) Boxer (Cenomanian): two distinct variants with moderate P/F, one quartz-rich and the other quartz-poor and feldspatholithic; (4) Cortina (Turonian-Coniacian): two similar variants with moderate P/F, one with Q-F-L proportions nearly equal and the other quartz-poor and feld-spatholithic; (5) Rumsey (Santonian-Campanian): quartz-rich lithofeldspathic with low P/F and high M. The nature of the petrofacies and their age can be related to the petrology and timing of dated intrusive episodes with inferred volcanic accompaniments in the Sierra Nevada. The Stony Creek petrofacies contains mainly volcanic debris erupted during the Yosemite magmatic epoch, and the overlying Lodoga petrofacies contains mainly plutonic debris emplaced during the same epoch, but only exposed to erosion by subsequent dissection. The Boxer and Cortina petrofacies contain mixed and intercalated volcanic and plutonic debris derived mainly from rocks erupted or emplaced during the Huntington Lake magmatic epoch. The slight differences between the Boxer and Cortina petrofacies may indicate that plutonic contributions were partly from older rocks for the Boxer, but volcanic contributions were essentially the same for both. The Rumsey facies contains mainly plutonic debris, with subordinate volcanic debris, derived from igneous rocks of the Cathedral Range magmatic epoch. Except locally or slightly, petrofacies boundaries do not transgress time-stratigraphic boundaries in the region. A close linkage among major magmatic, tectonic, and depositional events in arc-trench systems is implied.
Ecological biogeography of Malagasy non‐volant mammals: community structure is correlated with habitat

Aim To examine the relationship between ecoregions, as a proxy for regional climate and habitat type, and mammalian community structure, defined by species composition and richness (e.g. taxonomic structure) and ecological diversity (e.g. ecological structure) of non-volant species. Location Madagascar. Methods Faunal lists of non-volant mammal species occurring in 35 communities from five World Wildlife Fund ecoregions were collected from published and unpublished sources. Species were assigned to ecological groups defined by trophic status, locomotor habits, activity cycle and body mass. We used Mantel tests, cluster analysis and principal coordinates analysis to evaluate geographic patterning in taxonomic composition and species richness. We used stepwise multiple discriminant analysis to characterize patterns in the ecological diversity of the mammalian communities from each ecoregion. Communities from transitional habitats (e.g. representing more than one ecoregion) were used to test the predictive power of the analyses. Results Non-volant mammal communities divided into clusters that correspond to ecoregions. There was a strong distance effect in the taxonomic structure of communities across the island and within both humid and dry forest communities, but this effect was weak within humid forest communities. Mammalian species richness was significantly lower in dry forest than in humid forest communities. The ecological structure of communities was also correlated with ecoregions. Changes in the relative percentages of omnivory, arboreal quadrupedalism, terrestrial/arboreal quadrupedalism and two body mass classes accounted for 98.1% of the variation in ecological structure. Transitional communities were projected in intermediate positions by the discriminant model. Main conclusions Our analysis demonstrates that the broad-scale habitat and climate variables captured by the ecoregion model have shaped the assembly of non-volant mammal communities in Madagascar over evolutionary time. The spatial pattern is consistent with ecological sorting of species ranges along environmental gradients. Historical processes, such as recent extinction and migration, may have also affected the structure of mammal communities, although these factors have played a secondary role.
Effects of male age on the frequencies of germinal and heritable chromosomal abnormalities in humans and rodents

Abstract Objective To review evidence regarding the effects of male age on germinal and heritable chromosomal abnormalities using available human and rodent studies and to evaluate possible underlying mechanisms. Design Review of English language-published research using MEDLINE database, excluding case reports and anecdotal data. Result(s) There was little evidence from offspring or germ cell studies for a generalized male age effect on autosomal aneuploidy, except in rodents. Sex chromosomal nondisjunction increased with age in both human and rodent male germ cells. Both human and rodent data showed age-related increases in the number of sperm with chromosomal breaks and fragments and suggest that postmeiotic cells are particularly vulnerable to the effects of aging. Translocation frequencies increased with age in murine spermatocytes, at rates comparable to mouse and human somatic cells. Age-related mechanisms of induction may include accumulation of environmental damage, reduced efficiency of DNA repair, increased genomic instability, genetic factors, hormonal influences, suppressed apoptosis, or decreased effectiveness of antioxidants and micronutrients. Conclusion(s) The weight of evidence suggests that the increasing trend toward fathering at older ages may have significant effects on the viability and genetic health of human pregnancies and offspring, primarily as a result of structural chromosomal aberrations in sperm.
A current view of Alzheimer's disease.

Several genes that influence susceptibility to Alzheimer’s disease (AD) have been known for over two decades. Recent advances have elucidated novel candidate genes and the pathogenetic mechanisms underlying neurodegeneration in AD. Here, we summarize what we have learned from studies of the known AD genes with regard to the causes of AD and emerging therapies. We also review key recent discoveries that have enhanced our understanding of the etiology and pathogenesis of this devastating disease, based on new investigations into the genes and molecular mechanisms underlying AD.
Posicast-based digital control of the buck converter

The analysis, design, and microcontroller-based implementation of a digital controller using a Posicast element are presented for the buck converter. Posicast is a feedforward compensator that eliminates overshoot in system response, but the traditional approach is sensitive to variations in natural frequency. The new method described here reduces the undesirable sensitivity by using Posicast within a feedback loop. Compared to classical proportional-integral-derivative (PID) control, the new control results in lower noise in the control signal because the controller has a lower gain at high frequency. Furthermore, the authors' experiments indicate that the new controller is less sensitive to the inherent time delay associated with a digital controller for a dc-dc converter. The authors present a straightforward method to design controller parameters from the small-signal averaged model of the converter dynamics. Experimental results for a PID-controlled converter and Posicast-type controller are also compared.
Star chromatic number

A generalization of the chromatic number of a graph is introduced such that the colors are integers modulo n, and the colors on adjacent vertices are required to be as far apart as possible.
Human sperm competition in postindustrial ecologies: sperm competition cues predict adult DVD sales

Sperm competition theory has been used to generate the hypothesis that men prefer to view pornographic images suggesting the presence of a rival male, over images which do not. The current research uses a new methodology to address conflicting evidence about men’s preferences for pornographic images. Raters coded a random sample of 166 pornographic DVDs (from a population of 49 493), which were then analyzed using multiple regression. Consistent with the hypothesis generated from sperm competition theory, the number of images on a DVD cover and screenshots depicting 2 or more men interacting with 1 woman (suggesting the presence of sperm competition) predicts DVD sales rank, whereas the number of images on a DVD cover and screenshots depicting 2 or more women interacting with 1 man (suggesting the absence of sperm competition) does not predict DVD sales rank. Discussion addresses limitations and future directions, including using penile plethysmography to avoid relying on correlational analyses.