cssi/SciSciGPT-SciSciNet huggingface dataset:
A circadian clock regulates sensitivity to cadmium in Paramecium tetraurelia

The heavy metal cadmium is a dangerous environmental toxicant that can be lethal to humans and other organisms. This paper demonstrates that cadmium is lethal to the ciliated protozoan Paramecium tetraurelia and that a circadian clock modulates the sensitivity of the cells to cadmium. Various concentrations of cadmium were shown to increase the number of behavioral responses, decrease the swimming speed of cells, and generate large vacuole formation in cells prior to death. Cells were grown in either 12-h light/12-h dark or constant dark conditions exhibited a toxic response to 500 μM CdCl2; the sensitivity of the response was found to vary with a 24-h periodicity. Cells were most sensitive to cadmium at circadian time 0 (CT0), while they were least sensitive in the early evening (CT12). This rhythm persisted even when the cells were grown in constant dark. The oscillation in cadmium sensitivity was shown to be temperature-compensated; cells grown at 18°C and 28°C had a similar 24-h oscillation. Finally, phase shifting experiments demonstrated a phase-dependent response to light. These data establish the criteria required for a circadian clock and demonstrate that P. tetraurelia possesses a circadian-influenced regulatory component of the cadmium toxic response. The Paramecium system is shown to be an excellent model system for the study of the effects of biological rhythms on heavy metal toxicity.
A [polycation:heparin] complex releases growth factors with enhanced bioactivity

Growth factors are potent molecules that regulate cell functions including survival, self renewal, differentiation and proliferation. High-efficacy delivery of growth factors will be a powerful tool for regenerative medicine. Decades of intense research have significantly advanced the field of controlled delivery. There is, however, still a great unmet need for new methods that can improve overall efficacy of growth factor delivery. Here, we report a new growth factor delivery vehicle formed by self assembly of heparin and a biocompatible polycation, poly(ethylene argininylaspartate diglyceride) (PEAD). Of the many heparin-binding growth factors, we chose FGF-2 and NGF to demonstrate the potential of the [PEAD:heparin] delivery vehicle. The delivery vehicle incorporates both growth factors with high efficiency, controls their release, maintains the bioactivity of FGF-2 and increases the bioactivity of NGF relative to bolus delivery. [PEAD:heparin] appears to be a promising delivery matrix for many heparin-binding growth factors and may lead to efficient growth factor delivery for a variety of diseases and disabilities.
Cross-sectional TEM and KOH-Etch Studies of Extended Defects in 3C-SiC p + n Junction Diodes Grown on 4H-SiC Mesas

This article presents cross-sectional transmission electron microscopy and molten-potassium hydroxide etching studies of (111) 3C-SiC diodes which we previously reported to be free of forward-voltage drift despite abundant electroluminescent linear features presumed to be defects. Our results show that the majority of linear features are stacking faults lying in inclined {111} planes. Additionally, high densities of isolated etch pits (106–108 cm−2) are observed in 3C films grown on stepped 4H mesas, while 3C films nucleated on step-free 4H mesas exhibited orders of magnitude fewer etch pits and stacking faults. Defect formation mechanisms whose impetuses are steps on the 4H-SiC pregrowth mesa are discussed.
Life (and death) in a malignant tumour.

Lack of oxygen induces the death of cells at the centre of tumours. But cells with mutations in the p53 tumour suppressor can survive such conditions, providing yet another lead in the study of this notorious gene.
Gender Inequity and Quality of Life: A Macromarketing Perspective:

Consumption inequities have been explored within the consumer behavior and public policy literatures in marketing, but few investigations within these domains have examined their global dimensions....
E-textbooks at what cost? Performance and use of electronic v. print texts

While e-book sales continue to increase, electronic textbooks are not very popular with college students. This may be due to the fact that e-textbooks are read for different reasons and with different strategies than are e-books. Although previous research has documented this lack of preference for e-textbooks, student performance and use of electronic texts has yet to be thoroughly investigated, especially in naturalistic settings. This study examines students' use and performance on a variety of print and electronic formats in both laboratory and at-home conditions. Although students scored similarly across formats and conditions, reading time was significantly higher in the electronic conditions with this difference increasing for the home conditions. Similarly, self-reports of multi-tasking were significantly higher for electronic conditions in the home condition, possibly accounting for the disparities in reading time. We conclude by urging caution in the rush to assume that electronic textbooks are equivalent substitutes for traditional textbooks and argue for further investigation into the unique ways that students may interact with electronic texts to promote more effective design.
Learning from myocarditis: mimicry, chaos and black holes

Autoimmune myocarditis and its sequel, dilated cardiomyopathy, are major causes of heart failure, especially in children and young adults. We have developed animal models to investigate their pathogenesis by infecting genetically susceptible mice with coxsackievirus B3 or by immunizing them with cardiac myosin or its immunodominant peptide. A number of valuable lessons have emerged from our study of this paradigm of an infection-induced autoimmune disease. We understand more clearly how natural autoimmunity, as an important component of normal physiology, must be recalibrated regularly due to changes caused by infection or other internal and external stimuli. A new normal homeostatic platform will be established based on its evolutionary fitness. A loss of homeostasis with out-of-control normal autoimmunity leads to autoimmune disease. It is signified early on by a spread of an adaptive autoimmune response to novel epitopes and neighboring antigens. The progression from infection to normal, well-balanced autoimmunity to autoimmune disease and on to irreversible damage is a complex, step-wise process. Yet, chaos theory provides hope that the pattern is potentially predictable. Infection-induced autoimmune disease represents a sequence of events heading for a train wreck at the end of the line. Our aim in autoimmune disease research must be to stop the train before this happens.
Roentgenographic appearance of thyroid acropachy

Thyroid acropachy is a syndrome comprising clubbing of the fingers, exophthalmos, and pretibial myxoedema. Bone changes are often present though they are not necessarily a part of the syndrome. The authors report a patient showing typical bony changes in the hands and feet. Their patient had bony manifestations also in the lower ends of the radius, ulna, tibia and fibula on each side, and in the os calcis. Such an extensive distribution has not been reported before in thyroid acropachy. The authors describe what is known of the aetiology of the condition, and discuss some important differential diagnoses.
Boosting based text and non-text region classification

Layout analysis is a crucial process for document image understanding and information retrieval. Document layout analysis depends on page segmentation and block classification. This paper describes an algorithm for extracting blocks from document images and a boosting based method to classify those blocks as machine printed text or not. The feature vector which is fed into the boosting classifier consists of a four direction run-length histogram, and connected components features in both background and foreground. Using a combination of features through a boosting classifier, we obtain an accuracy of 99.5% on our test collection.
Organization of Work via a Natural Substance: Regulation of Nest Construction in Social Wasps

In social insects, colony-level complexity emerges from simple individual-level behaviors and interactions. In the evolution of insect societies, selection has acted to promote efficiency through division of labor. Nest construction of social wasps is an excellent model system to study division of labor and the performance of a decentralized behavioral regulation. After re-examination of Jeanne's (1996) demand-driven "non-taskmates feedback" hypothesis, an alternative mechanism is suggested whereby the regulation of behavior is based on a natural substance (water) which is itself also a building material. By experimenting with a simple model system, we show that the model's predictions agree with observational data and cover a wide range of evolutionary transitions. According to the internal and external parameters, the colony builds up storage of water that is used both as regulator and building material. Through individual interactions, pulp foragers and water foragers emerge from general laborers and their ratio becomes balanced. The emergent foragers ensure both the stabilization of the quantity of stored water and the steady construction of the nest according to the given conditions. Perturbations of the system alter colony-level dynamics in a similar way as was observed in nature: water and pulp addition increase pulp arrivals and building rate; removal of pulp foragers decreases pulp input and construction rate, but not the water influx; removal of water foragers causes overcompensation of water input after a delay. After comparing the predictions of the model to natural data, assumptions found in the literature on organization of work and regulation of behavior are re-examined. A new, more parsimonious model of organization of work is proposed that may cover wide variety of cases where hormones and learning cannot be accounted for the regulation of behavior.
ATHLETE: A Mobility and Manipulation System for the Moon

A robotic vehicle called ATHLETE - the all-terrain, hex-limbed, extra-terrestrial explorer is described, along with initial results of field tests of two prototype vehicles. This vehicle concept is capable of efficient rolling mobility on moderate terrain and walking mobility on extreme terrain. Each limb has a quick-disconnect tool adapter so that it can perform general-purpose handling, assembly, maintenance, and servicing tasks using any or all of the limbs.
High-resolution electron microscopy of 90° ferroelectric domain boundaries in BaTiO3 and Pb(Zr0.52Ti0.48)O3

Abstract 90° domain boundaries in BaTiO3 and PZT(52/48) have been studied with high-resolution electron microscopy. The high-resolution images with two-dimensional 4 A lattice fringes show that most 90° domain boundaries in BaTiO3 are parallel to (011) planes but can shift from one (011) plane to adjacent (011) planes. It is suggested that such shifts may occur on (01 1 ) or (001) planes. Across the domain boundary, lattice planes tilt about 0.5° in BaTiO3, which is close to the experimental value 0.6° from the selected-area diffraction pattern and the theoretical value 0.57°. In PZT(52/48), the tilt of lattice planes across the domain boundary in high-resolution images is only about 1°, which is smaller than the experimental value 2.8° from selected-area diffraction pattern and the value from theoretical calculation. The mismatch may indicate that in very thin films the lattice distortion and strain field can be relaxed. A diffuse dark contrast is found along 90° domain boundaries in both BaTiO3 and PZT(52/48) and is probably related to the lattice distortion or ionic displacement. The diffuse dark lines are about 4–10 unit cells wide around the domain boundary. Diffractograms from Fourier analysis of the regions in high-resolution images around the domain boundaries reveal the effects of the lattice distortion and strain field.
Cell senescence and hypermitogenic arrest

A diverse range of conditions, from mitogenic stimuli to cytotoxic stress, can induce cell senescence. Here, I propose that simultaneous stimulation of mitogen-activated pathways and downstream inhibition of cyclin-dependent kinases leads, ultimately, to cell senescence. This model distinguishes between two types of growth arrest: first, exit to G0 phase, which is caused by the withdrawal of mitogens and can lead to apoptosis; and second, hypermitogenic arrest, which is stimulated by mitogens and can lead to senescence. The concept of hypermitogenic arrest defines cell senescence as a functionally active, stable and conditionally reversible state.
Identification of oxidation products in selectively labeled polypropylene with solid-state 13C NMR techniques

Oxidatively degraded polypropylene (PP) samples, with selective 13C labeling of the three carbon sites on the PP chain (tertiary, secondary, and methyl carbons), have been analyzed with a suite of one- and two-dimensional solid-state 13C nuclear magnetic resonance (NMR) experiments that have been used to assign several 13C resonances attributed to oxidation-induced functional groups. These NMR techniques, several of which were recently developed, included dipolar dephasing for MAS speeds ≥10 kHz, chemical shift anisotropy (CSA) filtering, SUPER NMR to separate quasi-static CSA patterns, and 1H−13C heteronuclear correlation (HETCOR). In the course of the study, it has been demonstrated that NMR experiments which utilize the 13C CSA for resonance identification can be sensitive to sample temperature as a result of molecular motion-induced averaging of the CSA. These experiments have allowed hemiketal groups to be identified for the first time to our knowledge in oxidized PP. Possible mechanisms for the form...
Nonlinear Lyapunov-based control for HIV-1 dynamics

Nonlinear control theory plays an important role in stabilizing nonlinear dynamic systems such as the Human Immunodeficiency Virus type-1 (HIV-1) infectious disease. This disease targets immune system defenses and may eventually cause Acquired Immune Deficiency Syndrome (AIDS). In this paper, a nonlinear Lyapunov-based control for HIV-1 dynamic reduced models with real data is proposed. A Lyapunov function for a reduced model is constructed, and proof of its global stability is also provided. The feedback control laws using Jurdjevic-Quinn and Sontag designs are compared. The reduced HIV-1 model is stabilized implicitly through infected cells by using two different control laws. Feedback control law using Sontag's formula showed a slightly smoother performance and less of control effort. On the other hand, the Sontag formula needed more computation than the Jurdjevic-Quinn formula.
Abstract 2055: Influence of intermittent hypoxia on differentiation in neuroblastoma

Neuroblastomas are the most common extracranial solid tumors in children. Neuroblastomas derive from neural crest stem cells blocked at different stages of the sympathetic nervous system development. Neuroblastomas display a variety of histological features that range from undifferentiated tumors in patients with poor outcome to those containing differentiated cell types which show a better prognosis. Hypoxia has been linked to tumor progression and increased malignancy. Like the most common malignant solid tumors, neuroblastomas contain zones of chronic or acute hypoxia reflecting poor oxygenation. Transient hypoxia and subsequent reoxygenation are common phenomena in solid tumors that greatly influence the outcome of therapies. Differentiation is a key feature in pathologic classification and prognosis of neuroblastomas. The present study focuses on how intermittent hypoxia (IH) modulates the differentiation of neuroblastoma cells. IH-conditioned cells were derived by exposing tumor cells to 10 repeated cycles of hypoxia followed by reoxygenation. We found IH-induced changes in the expression of dedifferentiation markers and genes associated with neural crest-like phenotype in human neuroblastoma cells. The protein levels of HIF-1α, HIF-2α, tyrosine hydroxylase and c-kit were found upregulated in IH-conditioned human neuroblastoma cells as determined by western blotting. Similarly the expression of genes of neuronal crest phenotypic markers Oct-4, Notch-1and angiogenic molecule VEGF was found increased in IH-conditioned neuroblastoma cells. Expression of the cancer stem cell marker CD133 was also found increased in IH-conditioned neuroblastoma cells as evaluated by immunoflorescence analysis. Parallel studies were also performed in neuroblastoma cells exposed to hypoxia for 24h. It has been observed that IH-conditioned neuroblastoma cells exhibit increased expression of the proteins of dedifferentiation markers and genes associated with neural crest-like phenotype compared with neuroblastoma cells exposed to hypoxia for 24h. We cultured neuroblastoma cells, exposed the cells to defined doses of retinoic acid and studied neurite extension. A decrease in the levels of HIF-1α, and neuronal differentiation marker NF-M protein was observed in hypoxic neuroblastoma cells treated with retinoic acid. IH-conditioned neuroblastoma cells showed significantly less neurite extensions when compared with parental cells indicating that IH may suppress the differentiation of neuroblastoma cells. Taken together, our data suggest that IH inhibits differentiation and facilitates stem cell-like characteristics in human neuroblastoma cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2055. doi:10.1158/1538-7445.AM2011-2055
Alleviating I/O interference via caching and rate-controlled prefetching without degrading migration performance

The process of migrating a virtual machine and its virtual storage can greatly degrade the performance of other guests and applications running on the same host, including the migrating machine itself. Through experimental evaluation, we investigate the I/O performance degradation imposed by storage migration on co-located machines. We examine naive approaches for mitigating this interference by adjusting host system settings and migration parameters. While effective in some contexts, our analysis demonstrates that performing a migration using these I/O constraining techniques will increase migration latency and limit its ability to converge. Therefore, we present a design and analysis of Storage Migration Offloading, a migration method that reduces I/O interference, maintains lower migration latency, and converges under higher dirty rates. Storage Migration Offloading utilizes a buffer store populated during migration using a dynamic cache policy and rate controlled prefetching. Data is transferred to the destination host from both the buffer and primary disks in a way that minimizes interference on the primary disk while attempting to maintain the desired migration speed.
Influence of plastic strain on friction in sheet metal forming

Abstract A sheet metal forming simulator which stretches a strip around a cylindrical pin was used to investigate the relationship between friction and process variables including sliding speed, strip strain and strain-rate in the boundary lubrication regime. Measurements were conducted with two different sheet and tooling material combinations: electro-galvanized steel sheet on smooth A2 tool steel and commercially pure aluminum sheet on cemented carbide. In the first system, friction tends to increase with strain in contact. This supports a friction model which treats the influence of plastic strain on the flattening of strip asperities and real area of contact. In the second system friction was found to decrease with the strain in contact. This is apparently due to a decrease in contact area associated with roughening of the strip by plastic deformation.
Effect of hypoosmotic stress on peripheral-type benzodiazepine receptors in cultured astrocytes

Astrocytes appear to be the primary source of peripheral benzodiazepine (PBZD) receptors in brain. The function of this receptor is not well understood. Since there is evidence that this receptor may be involved in cell volume control, we examined the effect of hypoosmotic stress on the regulation of the PBZD receptors in homogenates of cultured astrocytes derived from neonatal rat cerebral cortex. Exposure of astrocytes that were maintained in the presence of dibutyryl cAMP (dBcAMP) to hypoosmotic medium (200 mOsm) for 24 h resulted in 27 and 57% increased in the number of [3H]PK 11195 and [3H]Ro5-4864-binding sites, respectively, as compared with isoosmotic media (320 mOsm). This receptor upregulation is osmolarity- and time-dependent. However, hypoosmotic stress had no effect on PBZD receptor-binding in astrocytes that were maintained in the absence of dBcAMP. Under isoosmotic conditions, dBcAMP appears to regulate [3H]Ro5-4864 but not [3H]PK 11195-binding sites, a finding which further supports a partial distinction between the binding sites labeled with these ligands. The modulation of PBZD receptors by hypoosmotic stress suggests a possible role for these receptor sites in astrocyte volume control.
THE KIDNEY IN HEPATIC DISEASE AND IN GOUT: CLINICAL AND PATHOLOGIC ASPECTS

The role of the kidney in hepatic disease and in gout has been surveyed. Kidney involvement is more common but less severe in hepatic disease, whereas it is less common but more severe in gout. The underlying pathology of the kidney lesions in both diseases (including studies by electron microscopy and immunofluorescence) is presented, with emphasis on the role this pathologic substratum plays in the renal insufficiency. The clinical aspects, including the diagnostic approach and therapeutic management of the "hepatorenal syndrome" and "gouty kidney" are discussed, as are the prognostic implications of the natural history of these "complications" and measures aimed at their prevention.
Turbulent Convection with Overshooting: Reynolds Stress Approach

The Reynolds stress formalism is adopted to treat turbulent convection. This methodology is reviewed, and it is suggested that it may prove very useful to treat stellar and accretion disk turbulent convection, as well as in the construction of the subgrid models needed in large eddy simulations. A set of differential equations that yield the mean and turbulent quantities such as convective fluxes, turbulent viscosity, and turbulent conductivity is presented.
Heterotopic abdominal pregnancy treated at laparoscopy

Abstract Objective: To report a case of laparoscopic treatment of a heterotopic primary abdominal pregnancy after IVF with preservation of the concurrent intrauterine pregnancy. Design: Case report. Setting: University-based IVF program. Patient(s): A woman with a heterotopic abdominal pregnancy after IVF-ET. Intervention(s): Pituitary down-regulation with luteal leuprolide acetate, ovulation induction with menotropins, IVF-ET, progesterone in oil for luteal support, laparoscopy, and resection of the abdominal gestation. Main Outcome Measure(s): Human chorionic gonadotropin levels, pelvic ultrasound examinations, and laparoscopic and pathologic findings. Result(s): A heterotopic abdominal pregnancy occurred after IVF-ET and was treated successfully with laparoscopy. The concurrent intrauterine pregnancy was delivered at term. Conclusion(s): Early diagnosis of an ectopic abdominal pregnancy allowed successful laparoscopic treatment, without sequelae to the intrauterine gestation.
Mammary nucleic acid, hydroxyproline, and hexosamine of pregnant rats during lactation and post-lactational involution.

Abstract Early stages of concurrent pregnancy during lactation had relatively little effect on lactational performance (litter weight gain), deoxyribonucleic acid (cell numbers), ribonucleic acid (protein synthetic acivity), hydroxyproline (collagen), and hexosamine (ground substance) content of the mammary glands of rats. However, during advanced stages of pregnancy, litter weight gains were depressed. This decreased laetational performance was associated with reduced mammary deoxyribonucleic acid, ribonucleic acid, and hydroxyproline, but not hexosamine content. Concurrent pregnancy during the early stages of post-lactational involution (dry period) retarded but did not prevent marked declines in the biochemical parameters. During the dry period of concurrently pregnant rats, minimum values of deoxyribonucleic acid, ribonucleic acid, hydroxyproline, and hexosamine were reached at pregnancy stages of 12, 16, 16, and 20 days, respectively. Increases in these biochemical constituents during the remainder of the dry period concurrent with gestation only partially replaced the losses which had occurred in the early dry period. Therefore, the rats entered their second lactation with less nucleic acid, hydroxyproline, and hexosamine than found at the time of weaning in the first lactation. It is concluded that despite concurrent pregnancy even in very short dry periods, involution of the mammary gland occurs.
A finite element model for compliant bearing lubrication using a minimization algorithm

Abstract A finite element numerical solution technique for compliant bearing lubrication is presented. The mechanics of the compliant bearing surfaces are obtained from a finite element model. The mechanics of the fluid lubricant are described by Reynold's equation. Coupling the behavior of the fluid lubricant and the compliant surfaces gives a set of non-linear equations. These are solved by a minimization algorithm. The solution technique is stable because each step provides a better solution than the previous step. For this reason, high load levels can be handled without the need for load incrementation. Numerical solutions compared well with those obtained by another numerical technique. In addition, a laboratory experiment involving a rubber sphere approaching a glass plate separated by a fluid lubricant was modeled. Results obtained from the model for the film thickness showed good agreement with data obtained from the literature. The finite element representation can handle a broad range of bearing geometries and the results indicate that the minimization technique offers an effective approach for solving compliant bearing problems.
Colorectal adenocarcinoma in patients less than 40 years old.

Carcinoma of the colorectum knows no age barrier. To date, more than 1,400 cases have been reported to occur in persons less than 40 years old. Our experience with 70 patients treated over a tenyear interval is reviewed. Signs and symptoms in the young are not distinctive. Diagnosis depends on a high index of suspicion and appropriate investigative procedures. Survival times are shorter in the patients who have mucinous and anaplastic tumors, and their incidences seem to be increased in this age segment. Overall survival does not significantly differ from our general experience (41 per cent, 5-year survival). Early diagnosis and prompt institution of aggressive surgical treatment can be expected to produce survival equivalent to that in patients of other ages.
Effects of Short-Term Fasting and Diurnal Heat Stress on Broiler Performance and Behavior

Abstract Experiments were conducted to test the effect of short-term (2-day) fasting and diurnal heating of the rearing environment on the performance, carcass yield, and behavior of 49-day-old broilers. In Experiment 1, female broilers were used. Birds in the heated environment were exposed to air temperatures that were above 35 C for 1.2 h and above 32 C for 4.7 h/day. Neither heated environment nor fasting alone significantly affected body weight gain, water consumption, or carcass yield parameters. However, the combination of heating and fasting resulted in the greatest reduction of body weight gain. Heating the environment resulted in consistently reduced feed consumption. In Experiment 2, male broilers were used. Heat-stressed birds had rearing environment temperatures above 35 C for 4.4 h and above 32 C for 6.1 h/day. Both heating the environment and fasting resulted in losses in body weight, although the difference for the unheated and fasted group did not differ significantly, from the unheated and fed group. However, full-fed birds that were heat stressed had significant body weight losses when compared with unheated/fed birds. Heating of the environment significantly reduced daytime feed consumption by 67 g/bird. Total feed consumption was significantly affected by both heating and fasting. Treatments affected daytime and overnight water consumption values. Analysis of behavioral data suggested that fasting of birds exposed to high daytime temperatures stimulated behaviors better suited to survival than behaviors of fed birds.
Macrophage response to concanavalin A: effect of surface crosslinking on the electrophoretic mobility distribution.

Abstract Electrophoretic light scattering (laser Doppler electrophoresis) has been employed to study the effects of concanavalin A (Con A) and succinyl-Con A on the electrophoretic mobility distribution of resident guinea pig peritoneal macrophages. Con A, a tetrameric lectin, decreases slightly the mean mobility and increases by approximately 3-fold the width of the electrophoretic mobility distribution of resident macrophages. This effect can be abolished by alpha-methyl-D-mannoside, a hapten sugar of Con A. These effects were present in both low (0.010 M) and high (physiological, 0.15 M) ionic-strength media. Since lower ionic strengths correspond to a larger Debye screening distance, these data suggest that the alterations in the electrophoretic mobility distribution are not restricted to the outer portion of the glycocalyx. Succinyl-Con A, a dimeric derivative, was found to have no effect on the mobility distribution. However, the mean mobility decreased and the width increased over 4-fold when succinyl-Con A-treated macrophages were exposed to anti-Con A. These observations indicate that cross-linking of Con A receptors is an important process in the electrokinetic alterations of the macrophage surface. These results may have important consequences for the elucidation of the details of the endocytic mechanism.
Nucleotide and metal interactions affecting inactivation of spinach chloroplast coupling factor by NaCl in the cold

Abstract The ability of isolated chloroplast coupling factor (CF 1 ) to hydrolyze ATP is destroyed when the enzyme is incubated in the cold. This inactivation is prevented completely by ATP at low concentrations and partially by adenosine imidodiphosphate. Other nucleotides, including ADP, GTP, GDP, and UTP, and also inorganic pyrophosphate, will prevent cold inactivation if certain divalent metal cations (Mg, Mn, Co, or Zn) are also present. These effects are taken as indications of binding of nucleotides to isolated CF 1 and the pattern of specificity is compared with those found in other experimental situations.
Limnology, Sedimentation, and Microorganisms of the Salton Sea, California

The Salton Sea, originally a fresh-water lake formed by the flood of the Colorado River in 1905, is located in the center of the Colorado Desert of California. By 1929, the water of the lake had become almost as saline as ocean water because of intense evaporation and solution of salts present on the floor of the basin before the flood. In recent years, in spite of the high rate of evaporation, excessive runoff from irrigation water has maintained and even raised the level of the lake. Evaluation of the water budget has made it possible to anticipate future changes in the chemical composition of the water— i.e., an increase in the amount of sulfates is predicted for the future. Measurements with a current cross and studies of salinity distribution indicate a counter-clockwise current pattern in the Salton Sea. Sands, silts, and clays are deposited in that order from the shore line to the center of the lake. The water content, amount of calcium carbonate, and textural characteristics indicate that most of the sediments of the Salton Sea were derived from the suspended load of the Colorado River, whereas the mineralogical study suggests that some of the sediments have a local origin. Two entirely different methods of computing the rate of sedimentation and of calculating the amount of calcium carbonate in the sediments give results of the same order of magnitude. The large amount of calcium carbonate is partly due to precipitation and partly to transportation by Colorado River water. Foraminifera are the most abundant microorganisms in the lake. Several ecological factors influence their distribution; among these factors, chlorinity and temperature are not important, depth may be important by its effect on other factors, but the variation in the pH of the sediments is significant. The living foraminiferal assemblage is due to accidental introduction, but the natural effect of environmental conditions has resulted in the creation of a dwarf fauna and many malformed individuals. In contrast to conditions in the ocean, abundance of species decreases offshore; however, as in the ocean, the number of living Foraminifera increases greatly after a bloom of phytoplankton. The average productivity of the Salton Sea is greater than that of the oceans. Conclusions derived from this study were applied to sediments deposited in the same basin during the past and made it possible to suggest a late Pliocene or early Pleistocene age for the Borrego formation and a Pleistocene age for the Brawley formation.
Low doses of dizocilpine block the development and subsequent expression of locomotor sensitization to nicotine in rats.

Rationale and objectives: We attempted to de- termine if the effects of the glutamate NMDA receptor blocker dizocilpine (MK-801) on nicotine locomotor sensitization were due to a blockade of the development of sensitization or to state-dependency. Methods and re- sults: In experiment 1, repeated co-administration of a high dose of dizocilpine (0.25 mg/kg) along with 0.4 mg/kg nicotine enhanced locomotion, failed to alter the development of locomotor sensitization to nicotine, but completely blocked the subsequent expression of sensitization to a challenge injection of nicotine alone. However, repeated injections of this dose of dizocilpine alone produced locomotion and sensitization that was equivalent to that produced by the dizocilpine/nicotine combination. In four separate replications in experiments 2 and 3, co-administration of a low dose of dizocilpine (0.075 mg/kg), which did not produce sensitization to it- self, blocked both the development of nicotine sensitiza- tion and its subsequent expression in response to a chal- lenge injection of nicotine. Moreover, this repeated di- zocilpine/nicotine administration did not affect the sub- sequent development of sensitization to nicotine alone (experiment 3). Suggesting that these effects of dizocil- pine may be confined to the development of sensitiza- tion, challenge injections of dizocilpine failed to block the capacity to express previously nicotine-sensitized lo- comotion (experiment 2). Conclusions: Co-administra- tion of a low dose of dizocilpine can block the develop- ment of locomotor sensitization to repeated injections of nicotine without producing state-dependency. Thus, NMDA receptor activation appears to be critical for the development, but not the subsequent expression, of nico- tine locomotor sensitization.
Functional Side Chain Interactions in ABCC Transporters Inferred by Improved Coevolution Analysis

Members of the ABCC sub-family of ABC transport proteins underlie insulin secretion, multidrug resistance in some cancers, and cystic fibrosis disease; unlike most other ABC proteins, they are characterized by two markedly dissimilar ATP binding sites. Recent X-ray structures illuminate numerous inter-residue interactions but it remains largely unknown which interactions are crucial for the signal transduction events that mediate conformational changes during transport. We have inferred such interactions by detecting coevolving pairs of amino-acid positions from aligned ABCC protein sequences using several current methods, which vary in their correction for phylogenetic relatedness, and their assumptions about how amino-acid substitutions occur. We evaluated the performance of these methods by testing their ability to predict side-chain contacts given a 3D structural model. Since the heterogeneity of amino-acid substitution rates generates correlations between positions and thus undermines accurate detection of coevolving pairs, we partitioned pairs into classes based on the rate of amino-acid substitutions at both positions of each pair. We then optimized the performance of the methods in three sequential steps: removal of the most redundant sequences from the alignment to correct for phylogenetic artifacts, logical combination of methods in proportion to their individual performances, and adjustment of the coevolution score of each pair according to the performance associated with that pair's substitution rate class. We verified that performance was improved by these procedures, in comparison to results obtained with each method separately and without partitioning pairs by substitution rate. As expected, many of the detected coevolving pairs bridge consecutive turns in alpha-helices in the structural model. Others, however, link distinct structural elements or domains, and so might transduce signals during the protein's conformational cycle. Intriguingly, some of the positions identified have been implicated in cystic fibrosis.[NIH-DK51767]
F2-Isoprostanes as Biomarkers of Late-onset Alzheimer’s Disease

Alzheimer’s disease (AD) is a syndrome caused by a few uncommon mutations that lead to early-onset disease, occurs in adults with Down’s syndrome, but is by far most commonly seen as a late-onset disease with multiple risk factors but no causative factors yet identified. Emerging data suggests a chronic disease model for AD with latency, prodrome, and dementia stages together lasting decades. Free radical damage to lipids in brain is one pathogenic process of AD that may be quantified with F2-isoprostanes (IsoPs). Whereas brain and cerebrospinal fluid (CSF) F2-IsoPs are reproducibly elevated in AD patients at both dementia and prodromal stages of disease, plasma and urine F2-IsoPs are not reproducibly increased in AD patients. CSF F2-IsoPs may be used to assist in diagnosis and aid in objective assessment of disease progression and response to therapeutics in patients with AD.
Vapor‐liquid equilibrium: Part III. Data reduction with precise expressions for GE

Through an empirical but rational appraoch to the development of equations to represent the composition dependence of the excess Gibbs function for binary liquid systems, it has been found possible to correlate VLE data precisely, even for highly nonideal systems. This makes possible the application of Barker's method to the reduction of VLE data on a routine basis. The validity of the method is demonstrated through application to several sets of data from the literature, and new experimental data are presented for six diverse binary systems in vapor-liquid equilibrium at 50°C.
Nanoencapsulation of Stem Cells within Polyelectrolyte Multilayer Shells

Mouse mesenchymal stem cells have been individually encased by polyelectrolyte layers of poly (L-lysine) and hyaluronic acid using the electrostatic layer-by-layer assembly technique, resulting in a shell consisting of nanolayers of thickness around 6-9 nm. Maintenance of cell morphology and viability were demonstrated for up to one week. Further adjustments to shell permeability and flexibility will facilitate the use of these encapsulated cells in tissue engineering and targeted-delivery applications.
Reconstruction of Tertiary palaeovalleys in the South Alpine Foreland Basin of France (Eocene–Oligocene of the Castellane arc)

Abstract The dynamics of depositional environments and the spatial deformation of drainage networks in foreland basins reflect the tectonic and erosional dynamics associated with the development of mountain belts. The spatial and temporal organization of the Eocene–Oligocene (40–25 Ma) sedimentation in the external part of the South Alpine Foreland Basin of France was reconstructed using an integrated cartographic, sedimentological and petrographic analysis of the Tertiary sedimentary successions. The depositional geometries and variations in facies and thickness of the Palaeogene Nummulitic succession, as well as the observed flow directions in various continental and marine sediments, suggest that the Barreme, Blieux and Taulanne synclines were present as palaeovalleys since the Eocene. The sedimentological analysis of the Nummulitic succession allows the identification of three depositional sequences separated by transgressive surfaces that are recognized in the Barreme, Blieux and Taulanne synclines. Correlation of these sequences between the three synclines suggests that these palaeovalleys were connected by a local valley network that recorded the same sea-level fluctuations during the marine Nummulitic sedimentation. The palaeovalley network was structurally controlled by the east–west axes of the Blieux and Taulanne synclines and the north–south axis of the Barreme syncline formed during the “Pyrenean–Provencal” (Late Cretaceous–Middle Eocene) shortening and the first stage of the Alpine history (Middle Eocene) respectively. Later on, the westward “Alpine” compression (since the Early Oligocene) induced local depocenter migration and reversal in flow direction. However, compared to the modern river pattern, the palaeovalley orientation highlights a geometrical stability since their formation (about 40 Ma), suggesting a long-term stability of the early structures in the foreland basin. This constancy can be explained by the location of the study area in a piggy-back basin transported at the top of the Provencal thrust sheet that facilitated the preservation of the overall axis orientation of the palaeovalleys.
Expression and ecdysteroid responsiveness of the nuclear receptors HR3 and E75 in the crustacean Daphnia magna.

Abstract Ecdysteroids initiate signaling along multiple pathways that regulate various aspects of development, maturation, and reproduction in arthropods. Signaling often involves the induction of downstream transcription factors that either positively or negatively regulate aspects of the pathway. We tested the hypothesis that crustaceans express the nuclear receptors HR3 (ortholog to vertebrate ROR) and E75 (ortholog to vertebrate rev-erb) in response to ecdysteroid signaling. HR3 and E75 cDNAs were cloned from the crustacean Daphnia magna . The DNA-binding domain and ligand-binding domain of the daphnid HR3 were 95% and 61% identical to those of Drosophila melanogaster . The DNA-binding domain and ligand-binding domain of the daphnid E75 were 100% and 71% identical to those of D. melanogaster . Both receptors exhibited structural characteristics of binding to DNA as a monomer. The expression of these receptor mRNAs was evaluated through the adult molt cycle and during embryo development. E75 levels were relatively constant throughout the adult molt cycle and through embryo development. HR3 levels were comparable to those of E75 during the initial phases of the adult molt cycle but were elevated ∼30-fold at a time in the cycle co-incident with the pre-molt surge in ecdysteroid levels. HR3 mRNA levels in embryos also varied co-incident with ecdysteroid levels. To substantiate a role of ecdysteroids in the expression of HR3, daphnids were continuously exposed to 20-hydroxyecdysone and changes in gene expression were measured. HR3 levels were significantly induced by 20-hydroxyecdysone; while E75 levels were minimally affected. These results are consistent with the premise that transcription of HR3 is regulated by ecdysteroids in the crustacean D. magna and that HR3 likely serves as a mediator of ecdysteroid regulatory action in crustaceans. The marginal induction of E75 by 20-hydroxyecdysone may represent limited, tissue or cell-type-specific induction of this transcription factor.
Ubiquitin marks the reactive swellings of diffuse axonal injury.

Ubiquitin is a protein that targets proteins for non-lysosomal degradation. It has been found to be present in a number of inclusions characteristic of neurodegenerative diseases. Using the fluid percussion model of diffuse axonal injury (DAI), we now report that the reactive axonal swellings and the retraction balls produced in this model stain positively with antiubiquitin immunohistochemistry. Furthermore, the affected axons become ubiquitin positive quickly (with-in the first 6 h after injury). Anti-ubiquitin immunohistochemistry compares well with the recently reported ability of antibodies to low molecular weight neurofilament proteins to demonstrate reactive axonal change in DAI, and it could provide additional clues to the pathogenesis of axonal transection.
WinXMorph: a computer program to draw crystal morphology, growth sectors and cross sections with export files in VRML V2.0 utf8-virtual reality format

A Microsoft Windows application for PC-users, WinXMorph, is introduced with which near reality crystal morphologies are made and exported as virtual reality files in the VRML V2.0 format.
Conformations of the glycine dipeptide

Integral equation theory is applied to the determination of the intramolecular potential of mean force for the glycine dipeptide, N-acetyl glycyl-N-methylamide, in aqueous solution. The solvated free energy for the dipeptide as a function of the dihedral angles ϕ and ψ (Ramachandran plot) is determined and compared with the vacuum surface. Conformations forbidden in vacuum are found to be populated in aqueous solution. The results of the glycine dipeptide are compared to a parallel study on the alanine dipeptide. Solvent effects are found to be responsible for the extent of many of glycines properties related to flexibility.
Organization for development: The politico‐administrative framework of economic activity in Egypt under Sadat

The open door (infitah) policy announced in 1974 marked the adoption of a new orientation for economic activity. This article relates the development of this policy towards economic enterprise to trends in the machinery of governmental control. The author argues that in the period of Sadat's presidency there was a contradiction between the liberalization in economic matters and the form and nature of control exercised by government.
Strain Distribution within Geosynthetic-Reinforced Slopes

Geosynthetic-reinforced slopes are conventionally designed using methods based on limit equilibrium. In order to estimate the factor of safety against internal stability using these methods, the distribution of the reinforcement peak tensile forces with height must be assumed. A linear distribution of reinforcement peak tension with height, with zero tension at the crest and maximum peak tension at the toe of the structure, has often been assumed. Although this assumption may be appropriate for the design of vertical geosynthetic-reinforced walls, little evidence has been collected so far justifying this distribution for the design of geosynthetic-reinforced slopes. A combination of centrifuge testing and digital image analysis is undertaken in order to obtain the strain distribution within geosynthetic-reinforced slopes under prefailure conditions. Specifically, digital image analysis techniques are used to determine the displacement distribution along reinforcement layers in reduced-scale models subjected to increasing g levels. A sigmoid function was useful to fit raw displacement data and estimate the strain distribution along reinforcement layers. Analysis of reinforcement strain results shows that the location of the reinforcement maximum peak strain does not occur near the toe of the structure, but was located approximately at midheight of the reinforced slopes, at the point along the critical failure surface directly below the crest of the slope. The pattern of reinforcement peak strain with height obtained for prefailure conditions is similar to that obtained for failure conditions. The estimated factor of safety is found to be a good indicator of the magnitude of the reinforcement maximum peak strain for geosynthetic-reinforced slopes built with different configurations.