cssi/SciSciGPT-SciSciNet huggingface dataset:
Predator avoidance behavior in the pea aphid: costs, frequency, and population consequences

Induced prey defenses can be costly. These costs have the potential to reduce prey survival or reproduction and, therefore, prey population growth. I estimated the potential for predators to suppress populations of pea aphids (Acyrthosiphon pisum) in alfalfa fields through the induction of pea aphid predator avoidance behavior. I quantified (1) the period of non-feeding activity that follows a disturbance event, (2) the effect of frequent disturbance on aphid reproduction, and (3) the frequency at which aphids are disturbed by predators. In combination, these three values predict that the disturbances induced by predators can substantially reduce aphid population growth. This result stems from the high frequency of predator-induced disturbance, and the observation that even brief disturbances reduce aphid reproduction. The potential for predators to suppress prey populations through induction of prey defenses may be strongest in systems where (1) predators frequently induce prey defensive responses, and (2) prey defenses incur acute survival or reproductive costs.
Frontiers and controversies in the pathobiology of vitiligo: separating the wheat from the chaff

The pathogenesis of vitiligo is complex and not well understood. Genes play a role in all aspects of vitiligo pathogenesis, and studies are ongoing to identify these genes and understand their biology. There is a body of interlocking, compelling evidence supporting an autoimmune basis for most or all cases of generalized vitiligo. The development of an autoimmune disease generally involves three components; the immune system, environmental triggers and other exogenous precipitating factors, and the target tissue. In vitiligo, precipitating factors could induce melanocyte damage in genetically susceptible individuals and consequent cell death, loss of tolerance, and induction of melanocyte-directed autoimmunity. Future research will more precisely define the multiple biological events that regulate development of vitiligo.
The calcium metabolism of the amphibian lens.

The Ca content of the amphibian lens is about 0·25 mmol/kg tissue, 15% of which is present in the extracellular space. Estimation of cell Ca by the “lanthanum method” indicates that a further 30% is associated with the outer regions of the cell membranes. The lens readily maintains its Ca content in vitro even when no Ca is added to the Ringer's solution. If EGTA is included, tissue Ca declines by about 65%. Elevation of external Ca from 0·8 to 2·5 mm results in a rise in tissue Ca. Exposure of the lens to iodoacetate and cyanide resulted in an elevation of tissue Ca. Ouabain or Na-free solutions was without effect. Tissue Ca was exchangeable with 45Ca in the external solutions 46% in 30 min, 69% in 3 hr and 78% in 16 hr. Non-exchanged Ca was sequestered in the lens nucleus but nearly all is exchangeable if this region was separated from the envoloping tissue. The anterior epithelium had no special role in the exchange process. Accumulation of external 45Ca was increased in the presence of the Ca ionophore A23187 and reduced by La3+ and Sr2+. It was unchanged by verapamil, amphotericin B, ouabain, ethacrynic acid, or exposure to Na-free solutions or high concentrations of K. Efflux of 45Ca from lenses was initially rapid (50% in 10 min), then slower (10% in 20 min) and then even slower (20% over 3·5 hr). Efflux was not detectably changed by a variety of drugs and external conditions including: A23187, verapamil, La3+, Sr2+, ouabain, EGTA, Na-free solutions, elevated K, etc. The results suggest that in the lens there is little “free” Ca in the cell water, a large proportion of the divalent ion being in a “bound”, but exchangeable form, much of which is associated with the cell membrane. Relatively low levels of “free” Ca are probably maintained as a result of the action of an energy dependent “Ca pump”, which extrudes Ca. CaNa exchange does not appear to be involved. Binding equilibria of lens Ca with internal and external “free” Ca also may play an important role in maintaining the tissue Ca.
BREEDING DENSITY IN THE PEREGRINE FALCO PEREGRINUS AND RAVEN CORVUS CORAX

SUMMARY 1The relative stability of breeding density in the Peregrine and Raven in certain inland districts is examined in relation to population limiting factors. Problems of cenus-making are considered, particularly the use of alternative nesting places. Breeding populations of the Raven have not fallen below 15% of the maxima since 1945. While the Peregrine now shows signs of local decline, it had numeral stability equal to the Raven during the preceding period, and this is the state under consideration. 2Of possible controlling factors, food supply is unlikely to be directly limiting. For breeding to occur, cliffs suitable in altitude, vertical height, cover and presence of ledges are necessary. Alternative cliffs and ledges are used if available but are not essential to ensure regular occupation of a territory. Availability of suitable cliffs controls nesting density at the lower levels, but does not impose an upper limit. 3The Golden Eagle is a dominant competitor for nesting cliffs and perhaps for food, and when nesting space is limited Peregrines and Ravens may compete with each other for cliffs. Deliberate persecution can deplete adult populations temporarily and reduce breeding success, especially in the Peregrine, but does not limit breeding density over a period, except in unsuitable terrain. For both species, breeding success and/or migration are sufficient to maintain numbers in the study regions. When breeding success is high, no increase in nesting populations follows. The Raven has non-breeding surplus populations during the breeding season but this is less certain for the Peregrine. 4Although direct evidence for its existence as defence of an area is scanty, territorialism is regarded as the factor controlling maximum nesting density by producing a “proximity tolerance limit” between adjacent nesting pairs. It is believed that such territorialism is not itself an ultimate limiting factor but has evolved in relation to food supply so that the numbers of predators are permanently balanced against this factor.
Structure and thermodynamics of anisotropic polymer fluids

We investigate the structure and thermodynamics of anisotropic polymer fluids, focusing on the nematic phases of flexible polymers. The chains interact only through monomer–monomer excluded-volume interactions. As a function of an externally provided alignment along a fixed nematic director, we calculate the anisotropic pair correlation function, and demonstrate the existence of two density correlation lengths, ξ⊥ and ξz, controlling transverse and longitudinal density fluctuations, respectively. We allow the possibility that the chains align either along the director (nematic conformations), or are anti-aligned in a “discotic-like” configuration. The cohesive contribution to the free energy is established in a high-temperature approximation, and its sensitivity to the orientation of the chains is probed. Our approach is not limited to homogeneous liquid crystalline phases, but applies in any circumstance when the orientation of otherwise disordered polymers is the physically controlling effect, e.g., con...
Photochemical Activity of Single Chloroplasts Recorded by the Use of Nuclear Track Emulsion

The photochemistry done by single chloroplasts can be measured when the chloroplasts are embedded in nuclear track emulsion. It has been known for more than 50 years that certain chemicals will blacken photographic plates (chemical fogging). Although this effect has been little used to measure chemical reactions, it may be particulary useful in photochemistry and electrochemistry, since as little as 10(-18) mole can be measured.
CASTER: a concept for a Black Hole Finder Probe based on the use of new scintillator technologies

The primary scientific mission of the Black Hole Finder Probe (BHFP), part of the NASA Beyond Einstein program, is to survey the local Universe for black holes over a wide range of mass and accretion rate. One approach to such a survey is a hard X-ray coded-aperture imaging mission operating in the 10-600 keV energy band, a spectral range that is considered to be especially useful in the detection of black hole sources. The development of new inorganic scintillator materials provides improved performance (for example, with regards to energy resolution and timing) that is well suited to the BHFP science requirements. Detection planes formed with these materials coupled with a new generation of readout devices represent a major advancement in the performance capabilities of scintillator-based gamma cameras. Here, we discuss the Coded Aperture Survey Telescope for Energetic Radiation (CASTER), a concept that represents a BHFP based on the use of the latest scintillator technology.
The Ohrid Agreement: The Travails of Inter-ethnic Relations in Macedonia

This article provides an overview of some of the key changes brought about by the groundbreaking Framework Agreement (known as the Ohrid Agreement) in Macedonia since its signing in 2001. A power-sharing arrangement, it saved Macedonia from the brink of civil war. This article describes how the Ohrid Agreement restored peace by addressing the constitutional status of minorities, their equitable representation in the public sector and issues connected with higher education in the 2002–2006 period. It further assesses the merits of decentralization as a remedy for safeguarding a unitary state in a multi-ethnic environment. It consequently argues that the Ohrid Agreement and the ensuing reforms have been important steps in the right direction revitalizing Macedonia by empowering not only the sizeable Albanian population but other less numerous communities as well. However, daunting challenges remain ahead. The perception and language gap between the two main ethnic communities hinder efforts for a truly functioning multi-ethnic state. Moreover, the new government formed after the July 2006 general elections has stirred controversy and caused tensions affecting its Euro-Atlantic perspective. To what extent this will affect Macedonia’s multi-ethnic democracy remains to be seen.
Long-term potentiation deficits and excitability changes following traumatic brain injury.

The effects of traumatic brain injury (TBI) on hippocampal long-term potentiation (LTP) and cellular excitability were assessed at postinjury days 2, 7, and 15. TBI was induced using a well-characterized central fluid-percussion model. LTP of the Schaffer collateral/commissural system was assessed in vivo in urethane-anesthetized rats. Significant LTP of the population excitatory postsynaptic potential (EPSP) slope was found only in controls, and no recovery to control levels was observed for any postinjury time point. Four measurement parameters reflecting pyramidal cell discharges (population spike) indicated that TBI significantly increased cellular excitability at postinjury day 2: (1) pretetanus baseline recording showed that TBI reduced population spike threshold and latency; (2) tetanic stimulation (400 Hz) increased population spike amplitudes to a greater degree in injured animals than in control animals; (3) tetanus-induced population spike latency shifts were greater in injured cases; and (4) tetanic stimulation elevated EPSP to spike ratios (E-S potentiation) to a greater degree in injured animals. These parameters returned to control levels, as measured on postinjury days 7 and 15. These results suggest that TBI-induced excitability changes persist at least through 2 days postinjury and involve a differential impairment of mechanisms subserving LTP of synaptic efficacy and mechanisms related to action potential generation
Accelerated removal of deferoxamine mesylate-chelated aluminum by charcoal hemoperfusion in hemodialysis patients.

Although deferoxamine mesylate (DFO) is effective in removing aluminum (AI) in hemodialysis patients, treatment with this drug is associated with a number of adverse effects. In order to limit the exposure of patients to DFO-AI complexes, the efficacy of colloidin-coated microencapsulated charcoal cartridges added in series to conventional dialyzers was investigated. The clearances of AI by the sorbent system were initially 116 ± 4.7 mL/min, but decreased to 42.5 ± 6.6 mL/min after 120 minutes of treatment. Thereafter, the Al clearances remained constant. In contrast, the AI clearances of the dialyzer were 29.5 ± 1.8 mL/min initially and did not change during the treatment period. Both the percent and absolute decrease in AI levels after four hours of dialysis were greater with the dialyzers plus carbon cartridges than with the dialyzers alone. This resulted in an increase in the minimum net AI removal from 1,862 ± 174 μg/treatment to 3,007 ± 43 μg/treatment (P
Critical exponents for the zero state Potts model in 2 + ϵ dimensions☆

Abstract Critical exponents for the zero state Potts model are calculated in 2 + ϵ dimensions using recursion relations obtained via the Migdal-Kadanoff bond moving approximation.
Pulsed-field gel analysis of α-satellite DNA at the human X chromosome centromere: High-frequency polymorphisms and array size estimate

Using pulsed-field gel analysis (PFGE), we have characterized the large array of alpha-satellite DNA located in the centromeric region of the human X chromosome. The tandem repetitive nature of this DNA family lends itself to examination by PFGE using restriction enzymes that cleave frequently in unique sequence DNA but which cut only rarely within the repetitive alpha-satellite array. Several such restriction enzymes (BglI, BglII, KpnI, ScaI) have proven highly informative in sizing the alpha-satellite array and in following the segregation of individual X-chromosome centromeres using PFGE polymorphisms. Among 29 different X chromosomes, alpha-satellite array length varied between 1380 and 3730 kb (mean = 2895 kb; SD = 537). In three large CEPH families comprising 24 meioses, inheritance of these PFGE polymorphisms was strictly Mendelian, with no indication of intraarray recombination. Such DXZ1 alpha-satellite polymorphisms, therefore, may prove useful in the study of pericentromeric X-linked disorders.
Contribution of Cystine–Glutamate Antiporters to the Psychotomimetic Effects of Phencyclidine

Altered glutamate signaling contributes to a myriad of neural disorders, including schizophrenia. While synaptic levels are intensely studied, nonvesicular release mechanisms, including cystine-glutamate exchange, maintain high steady-state glutamate levels in the extrasynaptic space. The existence of extrasynaptic receptors, including metabotropic group II glutamate receptors (mGluR), pose nonvesicular release mechanisms as unrecognized targets capable of contributing to pathological glutamate signaling. We tested the hypothesis that activation of cystine-glutamate antiporters using the cysteine prodrug N-acetylcysteine would blunt psychotomimetic effects in the rodent phencyclidine (PCP) model of schizophrenia. First, we demonstrate that PCP elevates extracellular glutamate in the prefrontal cortex, an effect that is blocked by N-acetylcysteine pretreatment. To determine the relevance of the above finding, we assessed social interaction and found that N-acetylcysteine reverses social withdrawal produced by repeated PCP. In a separate paradigm, acute PCP resulted in working memory deficits assessed using a discrete trial t-maze task, and this effect was also reversed by N-acetylcysteine pretreatment. The capacity of N-acetylcysteine to restore working memory was blocked by infusion of the cystine-glutamate antiporter inhibitor (S)-4-carboxyphenylglycine into the prefrontal cortex or systemic administration of the group II mGluR antagonist LY341495 indicating that the effects of N-acetylcysteine requires cystine-glutamate exchange and group II mGluR activation. Finally, protein levels from postmortem tissue obtained from schizophrenic patients revealed significant changes in the level of xCT, the active subunit for cystine-glutamate exchange, in the dorsolateral prefrontal cortex. These data advance cystine-glutamate antiporters as novel targets capable of reversing the psychotomimetic effects of PCP.
Validation of an integrated staging system toward improved prognostication of patients with localized renal cell carcinoma in an international population

ABSTRACTPurpose: Outcome prediction for patients with renal cell carcinoma is based on a combination of factors. In this study a previously published clinical outcome algorithm based on 1997 T stage, Fuhrman grade and performance score is validated using an international database.Materials and Methods: A total of 1,060 patients from Nijmegen, the Netherlands (NN), MD Anderson (MDA) and University of California, Los Angeles (UCLA) who had localized renal cell carcinoma were evaluated for outcome prediction using a clinical outcome algorithm previously shown to stratify patients into low, intermediate and high risk groups. Validation was performed by comparing the 3 risk groups separately within the 3 centers as well as by comparing hazard ratios and concordance indices among the 3 centers.Results: Estimated disease specific survival rates at 5 years for the low risk groups were 94% (NN), 92% (MDA) and 93% (UCLA). The 5-year disease specific survival rates for the intermediate risk groups were 65% (NN), 73%...
Laboratory Degradation Rates of 11 Pyrethroids under Aerobic and Anaerobic Conditions

Degradation of 11 pyrethroids was measured over approximately 100 days in three sediment/water systems under aerobic and anaerobic conditions at 25 °C in the dark. The three California sediments represented a range of textures and organic matter. Test compounds were bifenthrin, cypermethrin, ζ-cypermethrin, cyfluthrin, β-cyfluthrin, deltamethrin, esfenvalerate, fenpropathrin, γ-cyhalothrin, λ-cyhalothrin, and permethrin. A non-standard design was employed to keep conditions essentially the same for all compounds. The test compounds were applied as two test mixtures (six active ingredients per mixture, with bifenthrin common to both) at approximately 50 μg of test compound/kg of sediment (dry weight). Extracts of sediment/water were cleaned up by solid-phase extraction, concentrated, and analyzed by gas chromatography/mass spectrometry (except deltamethrin) against matrix-matched standards, with cyfluthrin-d6 as an internal standard. Deltamethrin was analyzed by liquid chromatography/tandem mass spectromet...
The control of relative size by pictorial depth cues in children and adults.

Abstract A developmental study of the relation between apparent size and pictorial depth demonstrated the usefulness of operant techniques in establishing equivalent differential responding and in testing stimulus equivalence in different age groups. A visual area discrimination was established by reinforcing, on a VR schedule, responses to the larger area in each pair of figures. Presenting pairs of figures of equal area on backgrounds with pictorial depth cues produced higher response rates to the pictorially further. This size “illusion” created by pictorial cues to depth proved very effective for adults, moderately effective for 9-year-olds, ineffective for 3-year-olds.
Resistance to noise-induced hearing loss in 129S6 and MOLF mice: identification of independent, overlapping, and interacting chromosomal regions

Noise-induced hearing loss (NIHL) is a prevalent health risk. Inbred mouse strains 129S6/SvEvTac (129S6) and MOLF/EiJ (MOLF) show strong NIHL resistance (NR) relative to CBA/CaJ (CBACa). In this study, we developed quantitative trait locus (QTL) maps for NR. We generated F1 animals by intercrossing (129S6 × CBACa) and (MOLF × CBACa). In each intercross, NR was recessive. N2 animals were produced by backcrossing F1s to their respective parental strain. The 232 N2-129S6 and 225 N2-MOLF progenies were evaluated for NR using auditory brainstem response. In 129S6, five QTL were identified on chromosomes (Chr) 17, 18, 14, 11, and 4, referred to as loci nr1, nr2, nr3, nr4, and nr5, respectively. In MOLF, four QTL were found on Chr 4, 17, 6, and 12, referred to as nr7, nr8, nr9, and nr10, respectively. Given that NR QTL were discovered on Chr 4 and 17 in both the N2-129S6 and N2-MOLF cross, we generated two consomic strains by separately transferring 129S6-derived Chr 4 and 17 into an otherwise CBACa background and a double-consomic strain by crossing the two strains. Phenotypic analysis of the consomic strains indicated that whole 129S6 Chr 4 contributes strongly to mid-frequency NR, while whole 129S6 Chr 17 contributes markedly to high-frequency NR. Therefore, we anticipated that the double-consomic strain containing Chr 4 and 17 would demonstrate NR across the mid- and high-frequency range. However, whole 129S6 Chr 17 masks the expression of mid-frequency NR from whole 129S6 Chr 4. To further dissect NR on 129S6 Chr 4 and 17, CBACa.129S6 congenic strains were generated for each chromosome. Phenotypic analysis of the Chr 17 CBACa.129S6 congenic strains further defined the NR region on proximal Chr 17, uncovered another NR locus (nr6) on distal Chr 17, and revealed an epistatic interaction between proximal and distal 129S6 Chr 17.
A Macromarketing Perspective on Social Marketing: The Case of Family Planning in India

Macromarketing's concern with intended and unintended effects of social marketing is examined in this article by focusing on the marketing of family planning in India. It is argued that the traditional emphases on marketing transactions can also be adopted in social marketing; however, the processes by which transactions are maximized can be highly disruptive and socially dysfunctional. By adopting a macro-marketing perspective, social marketing programs can be designed which are compatible with individual as well as collective welfare and which are equitable in their impact on society.
Dynamic Behavior Sequencing for Hybrid Robot Architectures

Hybrid robot control architectures separate planning, coordination, and sensing and acting into separate processing layers to provide autonomous robots both deliberative and reactive functionality. This approach results in systems that perform well in goal-oriented and dynamic environments. Often, the interfaces and intents of each functional layer are tightly coupled and hand coded so any system change requires several changes in the other layers. This work presents the dynamic behavior hierarchy generation (DBHG) algorithm, which uses an abstract behavior representation to automatically build a behavior hierarchy for meeting a task goal. The generation of the behavior hierarchy occurs without knowledge of the low-level implementation or the high-level goals the behaviors achieve. The algorithm's ability to automate the behavior hierarchy generation is demonstrated on a robot task of target search, identification, and extraction. An additional simulated experiment in which deliberation identifies which sensors to use to conserve power shows that no system modification or predefined task structures is required for the DBHG to dynamically build different behavior hierarchies.
Functional representation for the two-dimensional conformal group

Abstract A functional projective representation for the two-dimensional conformal group is explicitly constructed. The representation functionals are propagation kernels for self-dual fields.
The relationship between renal cortical volume and predisposition to hypertension

It has been proposed that a reduction in the number of nephrons is a renal abnormality that plays an important role in the pathogenesis of essential hypertension. The objective of this study was to determine whether renal cortical volume, used as a measure of the number of nephrons, is lower in normotensive subjects with a familial predisposition to develop essential hypertension than in subjects who lack this predisposition. For this purpose, we measured renal cortical volume using electron beam computed tomography in 26 white offspring of two hypertensive parents (OHT ; 14 women, 12 men) and 27 white offspring of two normotensive parents (ONT ; 13 women, 14 men) who were stabilized on a high sodium diet for 3 days (200 mmol/day). In women, mean age was significantly greater in OHT than ONT (46.1 ± 4.9 [standard deviation] v 41.8 ± 5.1 years, respectively, P =.04). In men, means for age and weight were greater in OHT than ONT (age : 47.1 ± 7.7 v 37.9 ± 8.1 years, P <.01 ; weight : 90.2 ± 10.7 v 81.1 ± 9.4 kg, P =.03.) In women, mean total cortical volume did not differ significantly between OHT and ONT (156 ± 33.3 v 166 ± 30.9 cc, P =.80). After adjustment for interindividual differences in age, mean total cortical volume remained not significantly different in OHT than ONT (160 ± 29.0 v 162 ± 32.4 cc, P =.83). In men, mean total cortical volume was significantly greater in OHT than ONT (210 ± 33.6 v 180 ± 20.0 cc, P <.01). After adjustment for interindividual differences in age, mean total cortical volume remained significantly greater in OHT than ONT (207 ± 33.2 v 182 ± 19.8 cc, P =.02). After adjustment for interindividual differences in body weight, mean total cortical volume did not differ significantly between OHT and ONT (201 ± 21.7 v 187 ± 20.1 cc, P =.09). The results of this study do not support the hypothesis that a decrease in renal cortical volume, as a result of a decrease in number of nephrons, is a characteristic of white women or men with a familial predisposition to develop essential hypertension. Am J Hypertens 1996 ;9 :779-786
Plastic-molded package of AlGaInP laser apparatus

A new apparatus is proposed for the package of AlGaInP visible laser diodes (LD) in this paper. Corresponding to the metal-can used in the conventional LD apparatus, plastics and lead-frame are used in this apparatus to reduce its cost. All the chip-mounting and wire- bonding for the apparatus are also modified to accord with the requirement of simplicity and good productivity. An lead-frame with a heat-dissipation tail is specially designed to overcome the poor heat-conductivity problem, which is observed in the common plastic-molded apparatus. The life time of the AlGaInP LD using the new plastic-molded apparatus is about five times longer than that using the common one.
Insulin permeation through thermo-sensitive hydrogels

Abstract A new class of thermo-sensitive hydrogels have been synthesized. These new polymers are used to investigate the effects of temperature on the permeation rates of a model macromolecule, insulin. This study reports the synthesis and aqueous swelling properties of poly(N-acryloyl pyrrolidine) (poly(APy)) and its copolymers with hydrophobic components, as well as insulin permeability through the membranes. As homopolymer, slightly crosslinked poly(APy) shows considerable thermo-sensitive properties, with difficulties in the insulin permeation study due to its weak mechanical properties. To allow a permeation experiment in a two-chamber diffusion cell, the mechanical properties of the membranes were improved by the addition of hydrophobic components, such as styrene (St) or 2-hydroxyethyl metacrylate (HEMA). In addition, these hydrophobic comonomers also altered the thermo-sensitivity and permeation properties. Specifically, the rate of permeation of insulin through poly(HEMA) increased with an increase in temperature. In contrast, rate of insulin permeation through APy copolymers increased with a decrease in temperature. The explanation for this phenomenon is centered around the swelling (hydration) properties of the polymers and the thermodynamic influence of temperature.
Environmental Cognitive Sets: A Longitudinal Study

This article reports the results of a longitudinal experiment exploring environmental cognitive sets (ways of perceiving or thinking about one's surroundings) that were designed especially to promote awareness of environmental problems and possibilities but also to induce aesthetic experience, environmental understanding, and a playful and creative orientation toward environmental experience. The results of our project indicate that (1) imagining improvements in an environment (the "IMG" set) led subjects to notice and remember more human-induced environmental problems than did normal viewing; (2) although IMG tended to be rated as more interesting and enjoyable than normal viewing for filmed scenes, subjects who were instructed repeatedly to use IMG seemed to tire of its imposed use over an extended period of time; (3) nevertheless, a much higher proportion of these subjects than of subjects with less experimental exposure to IMG reported using this set on their own after the conclusion of the experiment...
Experimental investigation of muon-catalyzed d-t fusion

Measurements of the absolute neutron yield and the time dependence of the appearance of neutrons resulting from muon-catalyzed fusion have been carried out in high-density deuterium-tritium mixtures. The temperature dependence of the resonant dt..mu..-molecular formation process has been determined in the range 100 to 540 K. Mesomolecular formation is found to be resonant for DT as well as D/sub 2/ target molecules. The sticking probability and other fundamental parameters have been measured for the first time.
Evaluation of YO-PRO-1 as an early marker of apoptosis following radiofrequency ablation of colon cancer liver metastases

Radiofrequency (RF) ablation (RFA) is a minimally invasive treatment for colorectal-cancer liver metastases (CLM) in selected nonsurgical patients. Unlike surgical resection, RFA is not followed by routine pathological examination of the target tumor and the surrounding liver tissue. The aim of this study was the evaluation of apoptotic events after RFA. Specifically, we evaluated YO-PRO-1 (YP1), a green fluorescent DNA marker for cells with compromised plasma membrane, as a potential, early marker of cell death. YP1 was applied on liver tissue adherent on the RF electrode used for CLM ablation, as well as on biopsy samples from the center and the margin of the ablation zone as depicted by dynamic CT immediately after RFA. Normal pig and mouse liver tissues were used for comparison. The same samples were also immunostained for fragmented DNA (TUNEL assay) and for active mitochondria (anti-OxPhos antibody). YP1 was also used simultaneously with propidium iodine (PI) to stain mouse liver and samples from ablated CLM. Following RFA of human CLM, more than 90 % of cells were positive for YP1. In nonablated, dissected pig and mouse liver however, we found similar YP1 signals (93.1 % and 65 %, respectively). In samples of intact mouse liver parenchyma, there was a significantly smaller proportion of YP1 positive cells (22.7 %). YP1 and PI staining was similar for ablated CLM. However in dissected normal mouse liver there was initial YP1 positivity and complete absence of the PI signal and only later there was PI signal. Conclusion: This is the first time that YP1 was applied in liver parenchymal tissue (rather than cell culture). The results suggest that YP1 is a very sensitive marker of early cellular events reflecting an early and widespread plasma membrane injury that allows YP1 penetration into the cells.
Computing phase change front and temperature histories in stochastic media

Although many phase change problems involve uncertain or stochastic properties, the computation of temperatures and front position is typically based on known properties. This paper considers the effect of uncertain or noisy properties, particularly the latent heat, and investigates the application of perturbation techniques, polynomial chaos, and Wick products in computing the temperatures and front position. These methods are dependent upon formulating the problem in a manner in which the uncertain properties appear in the differential equations and are thus limited in their applicability.Copyright © 2004 by ASME
The Death of a Pet: Implications for Loss and Bereavement Across the Lifespan

Abstract Companion animals play a distinct role in our lives and for many, they are a part of the family and not simply just a pet. Today, in the United States, there is an increasing emphasis placed on the relationships that we build with our pets. A healthy relationship with our pets also lends to translate into a healthier lifestyle. However, we usually learn at a fairly young age that these beloved creatures do not live as long as we do. The loss of a pet in childhood is frequently our first face-to-face encounter with death and often affects how we will grieve as adults. Particularly within the field of psychology, the way we mourn our animal friends has gained increasing importance. This article looks at the literature concerning bereavement across the adult lifespan and focuses on the similarities between the way we grieve for our loved ones, both human and animal. We address some of the controversies associated with euthanasia and the treatment and support available to those in mourning. Finally, ...
Effects of exogenous nitric oxide and hyperoxia on lung fibroblast viability and DNA fragmentation.

Effective lung repair after acute injury requires elimination of proliferating mesenchymal and inflammatory cells without inducing an acute inflammatory response or disturbing concomitant repair of lung microvasculature. Previous studies have shown that endogenous NO regulates programmed cell death in fibroblasts and can modulate wound fibroblast synthetic function. We hypothesized that exposure of human lung fibroblasts to NO gas would decrease viability and induce apoptotic cell death. Primary cultures of normal human lung fibroblasts were exposed for 4 h to room air (RA), 80% oxygen, NO (at either 20 or 50 ppm) blended with RA, or NO blended with 80% O(2), then incubated for 24 to 72 h. Cell viability was determined by fluorescence viability/cytotoxicity assay and DNA fragmentation by TUNEL assay. Peroxynitrite formation was assessed using immunoblotting for S-nitrosotyrosine. NO plus O(2) induced significant cell death at 20 and 50 ppm NO when compared to either RA or O(2) alone at both 24 and 72 h (p < 0.05). Incubation with superoxide dismutase (SOD), catalase (CAT) or SOD + CAT significantly decreased cell death in fibroblasts treated with NO(20)/O(2) and NO(50)/O(2) compared with controls (p < 0.05). NO(20)/O(2) and NO(50)/O(2) exposure significantly increased TUNEL mean fluorescence intensity (MFI), consistent with increased DNA fragmentation, compared to RA at 24 and 72 h (p < 0.05). Antioxidants decreased MFI in cells exposed to NO(20)/O(2) (CAT and SOD + CAT) compared to controls at 24 h (p < 0.05). Western blot analysis for S-nitrosotyrosine showed increased signal intensity in fibroblasts exposed to NO at 20 and 50 ppm plus O(2) compared to RA or O(2) alone. Incubation with SOD + CAT reduced signal intensity for peroxynitrite in cells exposed to NO(20)/O(2). We conclude that NO in hyperoxic conditions induces fibroblast cell death and DNA fragmentation, which could be partially mediated by peroxynitrite synthesis.
The Need for Education and Training in Geosciences for the Development of Third World Countries

(1991). The Need for Education and Training in Geosciences for the Development of Third World Countries. Water International: Vol. 16, No. 2, pp. 59-63.
Bivariate conditional sampling of buoyancy flux during an intense cold-air outbreak

Buoyancy fluxes in the marine atmospheric boundary layer (MABL) for the cloud street regime, observed during the Genesis of Atlantic Lows Experiment (GALE), have been analyzed using the technique of joint frequency distribution. For the lower half of the MABL, the results suggest that the buoyancy flux is mainly generated by the rising thermals and the sinking compensating ambient air, and is mainly consumed by the entrainment and detrainment of thermals, penetrative convection, and the entrainment from the MABL top. The results are compared to those from previous studies of mesoscale cellular convection (Air-Mass Transformation Experiment, AMTEX), the dry convective boundary layer, and the trade-wind MABL. For the lower MABL, the quadrant buoyancy fluxes, fractional coverages, and flux intensities are in good agreement with those of mesoscale cellular convection (AMTEX) and the dry convective boundary layer. The results suggest that, if the buoyancy flux is primarily driven by the temperature flux, the physical processes for generating buoyancy flux mentioned above are about the same for the lower boundary layers over land and ocean, even with different convective regimes. For the trade-wind MABL, the buoyancy flux is mainly driven by the moisture flux; the quadrant flux intensities are stronger than those of the other three studies except for the buoyant updrafts (thermals). These results suggest that the entrainment and detrainment of thermals are more effective in the trade-wind MABL than in the boundary layers driven by the temperature flux. Scale analysis of the buoyancy flux is in good agreement with that of AMTEX. For the lower half of the MABL, the buoyancy flux is mainly generated by the intermediate scale (200 m to 2 km), which includes the dominant convective thermals in the surface layer and the mixed layer. The scale smaller than 200 m is important only in the surface layer. The scale larger than 2 km, which includes the roll vortices, increases its significance upward. While most of the positive and negative fluxes are associated with the updrafts for the intermediate scale, the downdrafts are as important as updrafts for the larger scale.
Decadal Variability in the Large-Scale Sea Surface Height Field of the South Pacific Ocean: Observations and Causes

Large-scale sea surface height (SSH) changes in the extraequatorial South Pacific Ocean are investigated using satellite altimetry data of the past 12 yr. The decadal SSH signals in the 1990s were dominated by an increasing trend in the 30°–50°S band and a decreasing trend in the central South Pacific Ocean poleward of 50°S. In recent years since 2002 there has been a reversal in both of these trends. Spatially varying low-frequency SSH signals are also found in the tropical region of 10°–25°S where the decadal SSH trend is negative in the eastern basin, but positive in the western basin. To clarify the causes for these observed spatially varying SSH signals, a 11U2-layer reduced-gravity model that includes the wind-driven baroclinic Rossby wave dynamics and the responses forced by SSH changes along the South American coast was adopted. The model hindcasts the spatially varying decadal trends in the midlatitude and the eastern tropical regions well. Accumulation of the wind-forced SSH anomalies along Rossby wave characteristics is found to be important for both previously reported long-term trends and their reversals in recent years. The boundary forcing associated with the time-varying SSH signals along the South American coast is crucial for understanding the observed SSH signals of all time scales in the eastern tropical South Pacific basin, but it has little impact upon the midlatitude interior SSH signals.
Influence of dolichyl phosphate on permeability and stability of bilayer lipid membranes

Abstract The ionic permeability coefficients, ionic transference numbers, activation energy of ion transport and breakdown voltage of bilayer liquid membranes made from diolcoylphosphatidylcholine or its mixtures with dolichyl 12-phosphate have been studied. The electrical measurements showed that dolichyl phosphate in phospholipid bilayers decreases membrane permeability, changes membrane ionic selectivity and increases membrane stability. These results are discussed in light of the aggregation behavior and the intramolecular clustering of a dolichyl phosphate molecule in phospholipid membranes. From our data we suggest that the hydrophilic part of dolichyl phosphate molecules regulates their behavior in membranes.
Evaluating clinical decision support tools for medication administration safety in a simulated environment.

Abstract Objectives The specific aims of this study were to develop a methodology and tools for the design of clinical decision support systems to decrease the incidence of medication administration errors. Methods A mixed-methods design was utilized in this study. First, observations of medication administration practice were used to inform the design of a simulated information system with a variety of decision support tools. Then, nurses were observed administering medications in a simulated environment using the simulated system. Finally, the nurses participated in focus groups to provide input into system tools design. Observations of nurses' use of the decision support tools as well as semi-structured focus groups were used to evaluate nurses' use and perceptions of the utility of the system decision support tools. Results Nurses' evaluation of the medication administration decision support tools as well as their actual performance revealed a tendency to underestimate their need for support. Their preferences were for decision support that was short, color coded, and easily accessed. Observations of medication administration showed that nurses exhibit a variety of work processes to prepare and administer medications to patients and access system decision support tools at a variety of points in this process. System design should allow flexibility of multiple points and types of information delivery to accommodate variations in workflow to minimize the tendency for system workarounds. Conclusions This study was performed in one hospital and results may not generalize beyond this setting. However, this method used to design and test decision support could be transferred to other settings. Using simulation in this study provided a method for testing new information system design, related to a potentially dangerous procedure, in a manner that eliminated the hazards of potential unintended consequences for patients.
Comment: A global flood

Science fiction author Stephen Baxter hopes that a fictional account of global flooding will persuade people to engage with the realities of climate change
Microwave-assisted rapid synthesis of α-amino-β-lactams

Abstract A rapid and convenient approach to α-amino-β-lactams has been developed using the tetrachlorophthalimido group as a masked amino substituent. Reaction between glycine and tetrachlorophthalic anhydride in DMF for about 90 sec in a domestic microwave oven led to an imidoacetic acid in high yield; the corresponding acid chloride reacted with Schiff bases to provide mixtures of trans and cis β-lactams. Nearly exclusive formation of trans β-lactams could be achieved in some cases in a few minutes by conducting β-lactam formation under strong microwave irradiation. Facile conversion to α-amino-β-lactams was realized in 5–10 minutes via solventless reaction of these α-amino-β-lactams with ethylenediamine at room temperature.
Planning for the Census in the Year 2000

Considering the difficulties the [U.S.] Census Bureau does a remarkably good job at counting people. There are two current techniques for evaluating or adjusting the census: (a) demographic analysis uses administrative records to make independent population estimates which can be compared to census counts; (b) data from an independent sample survey can be used to estimate population coverage. If there is a large undercount these techniques may be accurate enough for adjustment. With a small undercount it is unlikely that current adjustment methodologies can improve on the census; instead adjustment could easily degrade the accuracy of the data. This article reviews plans for Census 2000 including proposals for adjustment in the light of past experience. (EXCERPT)
Preventing Coronary Heart Disease B Vitamins and Homocysteine

The list of preventable and reversible risk factors for atherosclerotic cardiovascular disease continues to grow. Cigarette smoking, high blood pressure, physical inactivity, elevated cholesterol, underlying lipoprotein abnormalities, lipoprotein(a), diabetes, overweight, male gender, and age are well-established risk factors. During the 1990s, there have been many reports associating elevated plasma homocysteine levels with arteriosclerotic cardiovascular disease and consistent evidence that dietary and supplemental folic acid can reduce homocysteine levels.1 2 The article by Robinson and colleagues3 in this issue of Circulation presents further evidence of the importance of homocysteine and suggestive evidence that plasma folate and plasma pyrixodal-l-phosphate (vitamin B6) are protective factors. Their study is part of the European Concerted Action Project,4 which examined 750 patients younger than age 60 with diagnoses within the previous 12 months of coronary, cerebrovascular, or peripheral vascular disease and 800 healthy control subjects. The patient groups were young (47 years for cases and 44 years for control subjects) and heterogeneous, with nonfatal clinical events or symptoms of arteriosclerotic cardiovascular disease supported by ECG, angiographic, or Doppler evidence; the study involved 19 centers in nine European countries. Men in the highest quintile for fasting total homocysteine (tHcy), compared with the remainder of the population, had an estimated relative risk of 2.2 (95% confidence interval [CI], 1.6 to 2.9), with a striking dose-response relationship and a more-than-multiplicative interaction with cigarette smoking and high blood pressure on vascular disease risk4 ; the corresponding estimated relative risk for coronary heart disease was similar (2.0; 95% CI 1.6 to 2.8). (tHcy is the sum of homocysteine and homocysteinyl moieties of oxidized disulfides, homocystine, and cysteine- homocysteine.) Robinson and colleagues3 examined three B vitamins in detail to determine their effects on fasting and post–methionine-loading tHcy levels and any independent effects on cardiovascular disease …
Intramolecular domain–domain association/dissociation and phosphoryl transfer in the mannitol transporter of Escherichia coli are not coupled

The Escherichia coli mannitol transporter (IIMtl) comprises three domains connected by flexible linkers: a transmembrane domain (C) and two cytoplasmic domains (A and B). IIMtl catalyzes three successive phosphoryl-transfer reactions: one intermolecular (from histidine phosphocarrier protein to the A domain) and two intramolecular (from the A to the B domain and from the B domain to the incoming sugar bound to the C domain). A key functional requirement of IIMtl is that the A and B cytoplasmic domains be able to rapidly associate and dissociate while maintaining reasonably high occupancy of an active stereospecific AB complex to ensure effective phosphoryl transfer along the pathway. We have investigated the rate of intramolecular domain–domain association and dissociation in IIBAMtl by using 1H relaxation dispersion spectroscopy in the rotating frame. The open, dissociated state (comprising an ensemble of states) and the closed, associated state (comprising the stereospecific complex) are approximately equally populated. The first-order rate constants for intramolecular association and dissociation are 1.7 (±0.3) × 104 and 1.8 (±0.4) × 104 s−1, respectively. These values compare to rate constants of ≈500 s−1 for A → B and B → A phosphoryl transfer, derived from qualitative line-shape analysis of 1H-15N correlation spectra taken during the course of active catalysis. Thus, on average, ≈80 association/dissociation events are required to effect a single phosphoryl-transfer reaction. We conclude that intramolecular phosphoryl transfer between the A and B domains of IIMtl is rate-limited by chemistry and not by the rate of formation or dissociation of a stereospecific complex in which the active sites are optimally apposed.