cssi/SciSciGPT-SciSciNet huggingface dataset:
Helping may be Harming: unintended negative consequences of providing social support

While social support is generally considered a helpful resource for employees, it can also serve as a job stressor. Unhelpful workplace social support (UWSS) is any action taken by a supervisor and...
A new genus and species of xanthoid crab (Decapoda: Brachyura) from offshore hard bank habitats in the Gulf of Mexico.

Speciose populations of small xanthoid crabs on offshore banks and reefs of the northern Gulf of Mexico include a new species that is not assignable to presently named genera. Morphological diagnoses of the new genus and species are underpinned by previously published gene sequence analyses, originally misattributed to another species but now known to apply to this taxon. Herein named Guinope tiara n. gen., n. sp., the species shows molecular phylogenetic affinities with the family Linnaeoxanthidae Stevcic, 2005, an ally of panopeid and pseudorhombilid crabs. Specimens from Occulina banks off the Florida Atlantic coast, previously regarded to represent Garthiope barbadensis (Rathbun, 1921), are not that species but instead morphologically assignable to Guinope n. gen. Whether they represent variants of Guinope tiara n. gen, n. sp. or a second species of the genus awaits the collection of fresh materials for DNA analyses.
Using microprojectiles to study the ballistic limit of polymer thin films.

The dynamic impact between a particle and a planar material is important in many high impact events, and there is a growing need to characterize the mechanical properties of light-weight polymeric materials at dynamic loading conditions. Here, a laser-induced projectile impact test (LIPIT) is employed to investigate the ballistic limit (V0) and materials properties at impact velocities ranging from 40 m s−1 to 70 m s−1. An analytical expression describing the various energy dissipation mechanisms is established to estimate the yield stress and elasticity for polycarbonate thin films. This measurement approach demonstrates the utility of using low sample mass for discovery of materials for impact mitigation, as well as high-throughput mechanical characterization at dynamic loading rates.
The Caenorhabditis elegans proteasome subunit RPN-12 is required for hermaphrodite germline sex determination and oocyte quality

Background The proteasome is a multi-subunit complex and a major proteolytic machinery in cells. Most subunits are essential for proteasome function, and depletion of individual subunits normally results in lethality. RPN-12/Rpn12/PSMD8 is a lid subunit of the 19S regulatory particle (RP) of the 26S proteasome. Studies in Caenorhabditis elegans demonstrated that RNAi depletion of RPN-12 does not result in lethality. RPN-12 has not been well studied in higher eukaryotes. In this study we investigate the biological significance of RPN-12 in C. elegans. Results We found that the null mutant rpn-12(av93) did not cause major impairment of the proteolytic activity of the proteasome. Most rpn-12(av93) hermaphrodites lack sperm leading to feminization of the germ line that can be partially rescued by mating to males. The lack of sperm phenotype can be suppressed by downregulation of TRA-1, a player in the hermaphrodite germline sex determination pathway. Also, rpn-12(av93) animals show significant nuclear accumulation of the meiotic kinase WEE-1.3, a protein predominantly localized to the perinuclear region. Interestingly, chemical inhibition of the proteasome did not cause nuclear accumulation of WEE-1.3. Conclusions RPN-12 plays a previously unknown role in oogenesis and the germline sex determination pathway in C. elegans hermaphrodites. This article is protected by copyright. All rights reserved.
Hidden long-distance movements by a migratory bird

Summary Technology has revolutionized our ability to track animals across the globe, significantly advancing our understanding of animal movement [ 1 , 2 ]. Technological and logistical challenges, however, have led to non-migratory movements that fall outside of the territory/home range paradigm, receiving less attention. This may have resulted in a widespread underestimation of the frequency and spatial scale at which animals either move outside of their territories and home ranges or adopt altogether different space-use strategies. We used a breeding-range-wide automated radio-telemetry system to track movements in a migratory songbird, the Kirtland’s warbler (Setophaga kirtlandii). By attaching radio tags on the wintering grounds and relocating the same individuals on the breeding grounds, we were able to sample the population without regard to their eventual breeding status or space-use strategy. We found that a surprising proportion of breeders and most non-breeders made long-distance (5–77 km) movements during the breeding season while conspecifics remained within their small territories. Movement frequency peaked during the nestling and fledgling periods, indicating that both breeders and non-breeders were likely prospecting to inform dispersal. A literature review revealed that Kirtland’s warblers moved farther than most species in absolute distances and farther than all other species relative to normal daily movements. We argue that similarly long-distance movements likely exist in many other species but have gone undetected because of technological limitations, research biases, and logistical challenges. Underestimation of the scale of these poorly understood life history behaviors has important implications for the ecology, evolution, and conservation of animals. Video Abstract Download : Download video (27MB)
COVID-19 Patient Education and Consumer Health Information Resources and Services

The health information needs of providers, patients, and consumers are continually evolving in response to the spread of COVID-19. Information professionals play key roles in counteracting the asso...
Exploring the Use of XPath Queries for Automated Assessment of Student Web Development Projects

Web development courses are core to Information Technology (IT) and Computer Science (CS) curriculums. As a result, hundreds of students each semester enroll in these courses to learn HTML, CSS, and JavaScript. This burdens faculty with the need to grade tens or hundreds of web assignments each semester. Few tools exist to automate the grading of such assignments. This research explores the use of XPath queries, which may be used to evaluate HTML documents due to their loose relationship to XML. A web application was constructed to graphically define XPath queries, then provided to web development faculty to regrade past assignments. Based on faculty feedback, it was determined that XPath queries are capable of limited grading of HTML document against past assignments. However, by designing new assignments tailored for automated grading and by enhancing the web application with additional features, it is clear a significant portion, if not all, of the HTML documents for a web development assignment may be automatically graded.
Chaos as a symmetry-breaking phenomenon

Chaos is an ubiquitous and fundamental phenomenon with a wide range of features pointing to a similar phenomenology. Although apparently distinct, it is natural to ask if all these features emerge ...
Signs, Signs, Everywhere Signs: The Wilderness Society v. Kane County Leaves Everyone Confused About Navigating a Right-of-Way Claim Under Revised Statute 2477

The Tenth Circuit’s recent decision in The Wilderness Society v. Kane County has changed the landscape of litigation arising out of Revised Statute 2477, a provision of the Mining Act of 1886 repealed by the Federal Land Policy and Management Act of 1976. Prior to this decision, the presumption was that the United States owned all federal public lands unless an adverse claimant proved otherwise. Moreover, any adverse claimant was required to bring an action under the Quiet Title Act to divest the federal government of title to its property. This decision turns both of those presumptions inside-out, provided that states and counties assert rights under R.S. 2477, regardless of whether they can be proven. This Article explores the history of R.S. 2477, its repeal by the Federal Land Policy and Management Act, and the Tenth Circuit’s historical treatment of R.S. 2477 claims. It also discusses why the Tenth Circuit’s holding in the Kane County case misconstrues the nature of an R.S. 2477 dispute, overlooks long-recognized presumptions about federal ownership of federal land, and ignores the myriad of legal issues involved in an R.S. 2477 dispute. Lastly, it makes specific suggestions about how the Tenth Circuit should address litigation surrounding the growing number of R.S. 2477 battles in years to come, to enable litigants and lower courts to more easily navigate this complex area of law.
A Bayes-inspired theory for optimally building an efficient coarse-grained folding force field

Because of their potential utility in predicting conformational changes and assessing folding dynamics, coarse-grained (CG) RNA folding models are appealing for rapid characterization of RNA molecules. Previously, we reported the iterative simulated RNA reference state (IsRNA) method for parameterizing a CG force field for RNA folding, which consecutively updates the simulation force field to reflect marginal distributions of folding coordinates in the structure database and extract various energy terms. While the IsRNA model was validated by showing close agreement between the IsRNA-simulated and experimentally observed distributions, here, we expand our theoretical understanding of the model and, in doing so, improve the parameterization process to optimize the subset of included folding coordinates, which leads to accelerated simulations. Using statistical mechanical theory, we analyze the underlying, Bayesian concept that drives parameterization of the energy function, providing a general method for developing predictive, knowledge-based, polymer force fields on the basis of limited data. Furthermore, we propose an optimal parameterization procedure, based on the principal of maximum entropy.
Ant foraging path use responds to different types of risk and their encounter probabilities

Ant colonies are likely able to access food locations by multiple paths that can vary predictably in length or mortality risk. To favor one path over another requires ants to perceive, communicate and act upon important differences in length and risk between paths. Here, we present replicate Linepithema humile colonies with four equal-length paths to a sugar source. The paths vary in probabilities of encountering a risk cue that range from 0 to 100%. The risk cues were either live workers of an aggressive competitor (Liometopum occidentale: LO) or only formic acid (FA), a defensive chemical common in many formicine species. Both the probabilities of encounter and type of cue affected path preferences. Although across both cues the zero-risk path was most used, the use was not exclusive and patterns of response to the cues differed significantly. More ants were on all the paths when the cue was LO rather than FA, leading to a higher success rate at finding food. Worker numbers on paths with LO did decline over time as consistent with recognizing neighbors to be ‘dear enemies’ that are a reduced threat to the colony. Similarly, changes in path usage suggested that the FA cue also became viewed as less threatening over time when competitors were never simultaneously present. The results are consistent with L. humile exhibiting the behavioral plasticity and communicative ability needed to categorize and predict risk to efficiently collect food while defending against other ant species.
Relugolix - new treatment for uterine fibroid-related heavy bleeding.

Limited pharmacological treatments for uterine leiomyomata (fibroids) are available. Now, two phase III trials lasting 24 weeks showed marked reduction in leiomyoma-related heavy menstrual bleeding with relugolix, a new orally active gonadotropin-releasing hormone antagonist with add-back oestrogen (to limit bone loss) and progestin (to limit endometrial changes from unopposed oestrogen).
We stand by our brand: Consumers’ post-food safety crisis purchase intention and moral reasoning

Abstract Despite the abundant evidence on the adverse effects of a food safety crisis on consumers, surprisingly little research has been conducted to explain the importance of consumers who are forgiving of failure. Drawing on a social intuitionist model, this study first tests the assumption that there is a distinction between the food safety crises vs. nonfood product crises from the moral psychology perspective. The results show that a food safety crisis evokes consumers’ stronger immorality judgment than a nonfood product crisis through disgust feeling. Then, the main study investigates the role of brand identification (affective-hot) and brand attitude strength (cognitive-cold) on the moral reasoning processes, including moral rationalization and moral decoupling. Results show that brand identification is an important indicator of both moral rationalization and moral decoupling strategies, while brand attitude strength only affects the moral decoupling, thus influencing consumers’ purchase intention.
Pop-up kirigami for stiff, dome-like structures

Abstract In architecture and engineering, surfaces with positive Gaussian curvature such as domes are used for their high stiffness-to-weight ratios and efficiency in enclosing a volume. These curved shapes are difficult to create due to time-consuming or scale-limited processes. In recent years, origami and kirigami have risen as viable routes for the rapid fabrication of complex surfaces from flat sheets; however, these methods typically lead to systems that are overly flexible due to their high number of degrees of freedom. In this paper, we present a design for a pop-up kirigami system that achieves symmetric, positive Gaussian curvature by taking advantage of an internal infinitesimal mechanism. The system is fabricated from flat sheets using a hexagonal pattern, and the sheets remain flat locally as the system deforms into a dome-like shape. We investigate the internal mechanism and deformation modes of the system, revealing the flexible mode that creates dome-like curvature. We discuss geometric variations of the system and illustrate the possible shapes that result from changing the initial pattern parameters. Finally, we demonstrate the high stiffness of the system that arises from restricting its one flexible mode in its final, dome-like shape. The proposed pop-up kirigami system offers a method for fabricating dome-like surfaces with potential applications as deployable enclosures, concave reflectors, and more.
Coronary artery bypass grafting in low ejection fraction: state of the art.

Purpose of review As the number of patients with reduced ejection fraction secondary to ischemic cardiomyopathy (ICM) increases, coronary artery bypass grafting is being used with increasing frequency. In this review, we summarize the different operative considerations in this vulnerable patient population. Recent findings Preoperative optimization with mechanical circulatory support devices, especially in the setting of hemodynamic instability, can reduce perioperative morbidity and mortality. The advantage of advanced techniques, such as off-pump CABG and multiple arterial grafting remains unclear. Concomitant procedures, such as ablation for atrial fibrillation remain important considerations that should be tailored to the individual patients risk profile. Summary Despite improvements in perioperative care of patients undergoing CABG, patients with a reduced ejection fraction remain at elevated risk of major morbidity and mortality. Preoperative optimization and careful selection of intraoperative techniques can lead to improved outcomes.
Delayed response of groundwater to multi-year meteorological droughts in the absence of anthropogenic management

Abstract Groundwater is a life-sustaining resource that supplies water to 2 billion people worldwide and is critical for agriculture. Despite the importance of groundwater, understanding of groundwater recovery from meteorological droughts is limited. Here, we utilize daily groundwater observations from unconfined aquifers without active groundwater management across the conterminous United States to illustrate that in response to a multi-year drought, it takes on average, 3 years for shallow aquifers to recover the storage lost during the drought. This recovery time increases with higher drought severity, and is influenced by the time-lag between the initiation (termination) of a meteorological drought and initiation (termination) of a groundwater drought. There is considerable variation in the time-lag duration, up to 15 years in some aquifers, controlled by geographic properties in regions with shallow water tables and precipitation characteristics in regions with deep water tables. A machine learning algorithm finds that the most important controls on the time-lag are the drought intensity at the beginning of the precipitation drought and the mean annual recharge. Projected increases in drought severity could potentially increase groundwater recovery times to droughts in a changing climate.
(MIS-)USING THE TAX SYSTEM TO SUBSIDIZE HEALTH SPENDING

Health reform created the opportunity to redirect tax incentives to promote greater equity, effi ciency, and choice in insurance markets. The opportunity, however, has largely been lost. First, tax credits for insurance will be available only through new health insurance exchanges, not to workers with coverage through their employers, which discriminates against one group of low-income people over another based on where they work, not what they can afford. Second, the “Cadillac” tax on highcost insurance is intended to improve incentives for effi ciency in the health system, but it is only a half step that also creates new inequities. Third, new taxes imposed on insurers and health suppliers will ultimately be paid by consumers, contrary to some claims. Finally, a new Medicare tax fails to stabilize the program’s fi nancing and could have the perverse effect of delaying adoption of diffi cult policy actions needed to place Medicare on a sustainable fi scal path.
Intrinsic Quantum Anomalous Hall Effect in the Kagome Lattice Cs 2 LiMn 3 F 12

In a kagome lattice, the time reversal symmetry can be broken by a staggered magnetic flux emerging from ferromagnetic ordering and intrinsic spin-orbit coupling, leading to several well-separated nontrivial Chern bands and intrinsic quantum anomalous Hall effect. Based on this idea and ab initio calculations, we propose the realization of the intrinsic quantum anomalous Hall effect in the single layer Cs_{2}Mn_{3}F_{12} kagome lattice and on the (001) surface of a Cs_{2}LiMn_{3}F_{12} single crystal by modifying the carrier coverage on it, where the band gap is around 20 meV. Moreover, a simplified tight binding model based on the in-plane ddσ antibonding states is constructed to understand the topological band structures of the system.
Autonomously stabilized entanglement between two superconducting quantum bits

An entangled Bell state of two superconducting quantum bits can be stabilized for an arbitrary time using an autonomous feedback scheme, that is, one that does not require a complicated external error-correcting feedback loop. Entangled states are a key resource in fundamental quantum physics, quantum cryptography and quantum computation. It has been generally assumed that the creation of such states requires the avoidance of contact with a dissipative environment, and minimization of decoherence. Some studies have shown, however, that dissipative interactions can be used to preserve coherence, and in this issue of Nature two groups demonstrate this principle for continuously driven physical systems. Lin et al. use engineered dissipation to deterministically produce and stabilize entanglement between two trapped-ion qubits, independent of their initial state. Shankar et al. use an autonomous feedback scheme to counteract decoherence and demonstrate the stabilization of an entangled Bell state of a quantum register of two superconducting qubits for an arbitrary time. This approach may be applied to a broad range of experimental systems to achieve desired quantum dynamics or steady states. Quantum error correction codes are designed to protect an arbitrary state of a multi-qubit register from decoherence-induced errors1, but their implementation is an outstanding challenge in the development of large-scale quantum computers. The first step is to stabilize a non-equilibrium state of a simple quantum system, such as a quantum bit (qubit) or a cavity mode, in the presence of decoherence. This has recently been accomplished using measurement-based feedback schemes2,3,4,5. The next step is to prepare and stabilize a state of a composite system6,7,8. Here we demonstrate the stabilization of an entangled Bell state of a quantum register of two superconducting qubits for an arbitrary time. Our result is achieved using an autonomous feedback scheme that combines continuous drives along with a specifically engineered coupling between the two-qubit register and a dissipative reservoir. Similar autonomous feedback techniques have been used for qubit reset9, single-qubit state stabilization10, and the creation11 and stabilization6 of states of multipartite quantum systems. Unlike conventional, measurement-based schemes, the autonomous approach uses engineered dissipation to counteract decoherence12,13,14,15, obviating the need for a complicated external feedback loop to correct errors. Instead, the feedback loop is built into the Hamiltonian such that the steady state of the system in the presence of drives and dissipation is a Bell state, an essential building block for quantum information processing. Such autonomous schemes, which are broadly applicable to a variety of physical systems, as demonstrated by the accompanying paper on trapped ion qubits16, will be an essential tool for the implementation of quantum error correction.
Magnetic resonance imaging phenotyping of Becker muscular dystrophy.

Introduction: There is little information on magnetic resonance imaging (MRI) phenotypes of Becker muscular dystrophy (BMD). This study presents the MRI phenotyping of the upper and lower extremities of a large cohort of BMD patients. Methods: In this retrospective study, MRI images of 33 BMD subjects were evaluated for severity, distribution, and symmetry of involvement. Results: Teres major, triceps long head, biceps brachii long head, gluteus maximus, gluteus medius, vasti, adductor longus, adductor magnus, semitendinosus, semimembranosus, and biceps femoris muscles showed the highest severity and frequency of involvement. All analyzed muscles had a high frequency of symmetric involvement. There was significant variability of involvement between muscles within some muscle groups, most notably the arm abductors, posterior arm muscles, medial thigh muscles, and lateral hip rotators. Conclusions: This study showed a distinctive pattern of involvement of extremity muscles in BMD subjects. Muscle Nerve 50: 962–967, 2014
Kinetics and extent of mineralization of organic chemicals at trace levels in freshwater and sewage.

A sensitive and rapid method was developed to measure the mineralization of 14C-labeled organic compounds at picogram-per-milliliter or lower levels in samples of natural waters and sewage. Mineralization was considered to be equivalent to the loss of radioactivity from solutions. From 93 to 98% of benzoate, benzylamine, aniline, phenol, and 2,4-dichlorophenoxyacetate at one or more concentrations below 300 ng/ml was mineralized in samples of lake waters and sewage, indicating little or no incorporation of carbon into microbial cells. Assimilation of 14C by the cells mineralizing benzylamine in lake water was not detected. Mineralization in lake waters was linear with time for aniline at 5.7 pg to 500 ng/ml, benzylamine at 310 ng/ml, phenol at 102 fg to 10 mg/ml, 2,4-dichlorophenoxyacetate at 1.5 pg/ml, and di-(2-ethylhexyl) phthalate at 21 pg to 200 ng/ml, but it was exponential at several p-nitrophenol concentrations. The rate of mineralization of 50 and 500 ng of aniline per ml and 200 pg and 2.0 ng of the phthalate per ml increased with time in lake waters. The phthalate and 2,4-dichlorophenoxyacetate were mineralized in samples from a eutrophic but not an oligotrophic lake. Addition to eutrophic lake water of a benzoate-utilizing bacterium did not increase the rate of benzoate mineralization at 34 and 350 pg/ml but did so at 5 and 50 ng/ml. Glucose and phenol reduced the percentage of p-nitrophenol mineralized at p-nitrophenol concentrations of 200 ng/ml but not at 22.6 pg/ml and inhibited the rates of mineralization at both concentrations. These results show that the kinetics of mineralization, the capacity of the aquatic community to assimilate carbon from the substrate or the extent of assimilation, and the sensitivity of the mineralizing populations to organic compounds are different at trace levels than at higher concentrations of organic compounds.
Chapter 10 Macrophages: Their Use in Elucidation of the Cytoskeletal Roles of Actin

Publisher Summary This chapter discusses the use of macrophages in elucidation of the cytoskeletal roles of actin. Macrophages have a specialized layer of cytoplasm located just beneath their plasma membrane. This cortical cytoplasm is dynamic, undergoing changes in size and shape during cell movement. In macrophages it forms a variety of cortical protrusions or extrusions, including pseudopodia, membrane ruffles, and microvilli. Actin filaments predominate in electron micrographs of the macrophage cortex and seem to be organized into a dense network of short, highly branched filaments. Actin is the most abundant protein of macrophages, constituting 12% of the total cell protein. Macrophage actin, as is the case for all other nonmuscle actins is a 42,000-dalton globular protein indistinguishable from muscle actin in all important aspects. The rigidity of actin filaments of known length distribution in solution is markedly increased by actin-binding protein at concentrations near those predicted by the network theory. The shortening of filaments by gelsolin could occur by two different mechanisms. The random binding of gelsolin to filaments could lead to severing and shortening of the filaments.
Reciprocal Carriage of Vertically Integrated Cable Networks: An Empirical Study

Using a dataset of carriage decisions by 943 cable systems for 22 start-up basic cable networks, this study tests the “reciprocal carriage” hypothesis: the theory that multiple cable television system operators (MSOs) tacitly collude to carry each others’ vertically integrated cable networks. The research supports the reciprocal carriage hypothesis by finding that: (1) A vertically integrated MSO is more likely than a non-vertically integrated MSO to carry the start-up basic cable networks of other MSOs; and, (2) a vertically integrated MSO is no more likely than a non-vertically integrated MSO to carry independent start-up basic cable networks. These results make credible an underlying premise of a 30 percent national market share limit that the Federal Communication Commission established in 1993: namely, that MSOs may tacitly collude in their carriage decisions, having the effect of restricting market access to startup cable networks in which those MSOs have no ownership interest. The study suggests the difficulty of the entry and growth of non-vertically integrated independent start-up cable networks. More generally, this study suggests circumstances under which vertically integrated firms may tacitly collude to reciprocally buy each others’ intermediate goods
Indications of melt in near-surface ice-core stratigraphy: comparisons with passive-microwave melt signals over the Greenland ice sheet

During the summer of 1993, a field program was conducted to collect several shallow firn cores from two locations in the southern region of the Greenland ice sheet. Stratigraphic evidence of melt from these cores was used for comparison with satellite-derived indications of melt. The shallow firn cores were examined for stratigraphic evidence of past melt events and were sampled for oxygen-isotope analysis to delineate the annual accumulation layers in the snowpack. The relative intensity of each year’s summer melt episode was compared to the corresponding melt frequency derived from microwave emissions. This comparison demonstrates that a linkage between the stratigraphic record and microwave data can be established. Both data sets indicate that there was less melt during the late 1970s and early 1980s than during the late 1980s, in general agreement with climate observations.
Preparation of natural methane samples for stable isotope and radiocarbon analysis

We describe procedures for preparing methane samples from natural waters or sediments for radiocarbon (14C-CH4) analysis. These procedures also allow the determination of 2H/1H and 13C/12C ratios of this methane. Methane is extracted from natural samples in the field using Lamont radon stripping boards (Mathieu et al. 1988) and trapped using liquid nitrogen-cooled U-traps filled with HiSiv 3000. The field procedures eliminate the need to return large samples to the laboratory. The U-traps are returned to the laboratory where a new two-stage purification-oxidation vacuum line is used to extract, purify, and oxidize the methane. The methane oxidation products (carbon dioxide and water) are analyzed for the natural content of 14C, 2H, and 13C with standard procedures. These procedures were evaluated under the conditions that methane was extracted from between 19 to 114 L water or 0.07 to 0.35 L sediment. No isotope fractionation was observed and the blanks are small (0.528 ± 0.39 μmol methane with radiocarbon content 14C/C = 96.1 ± 0.3 pMC [percent Modern Carbon] [Stuiver and Polach 1977]). Using 14C-accelerator mass spectrometry (AMS), these procedures can produce a successful radiocarbon measurement when at least 1.81 μmol methane are collected. Thus, 14C-CH4 measurements can be made when the dissolved methane concentration is between saturation (mM) and 15.9 nM for the water column or 5.2 μM for the sediment. © 2005, by the American Society of Limnology and Oceanography, Inc.
Synergistic cytotoxicity of Δ9-tetrahydrocannabinol and butylated hydroxyanisole

We examined the food additive, butylated hydroxyanisole (BHA), for its capacity to modulate the cytotoxic effects of Delta(9)-tetrahydrocannabinol (THC). THC was not cytotoxic when added to cultures of A549 lung tumor cells at concentrations<5 microg/ml, but induced cell necrosis at higher levels with an LC(50)=16-18 microg/ml. BHA alone, at concentrations of 10-200 microM, produced limited cell toxicity but significantly enhanced the necrotic death resulting from concurrent exposure to THC. In the presence of BHA at 200 microM, the LC(50) for THC decreased to 10-12 microg/ml. Similar results were obtained with smoke extracts prepared from marijuana cigarettes, but not with extracts from tobacco or placebo marijuana cigarettes (containing no THC). Two different mechanisms for this synergistic cytotoxicity were investigated. Experiments were repeated in the presence of either diphenyleneiodonium or dicumarol as inhibitors of the redox cycling pathway. Neither of these compounds protected cells from the effects of combined THC and BHA, but rather enhanced necrotic cell death. Measurements of cellular ATP revealed that both THC and BHA reduced ATP levels in A549 cells, consistent with toxic effects on mitochondrial electron transport. The combination was synergistic in this respect, reducing ATP levels to <15% of control. Exposure to marijuana smoke in conjunction with BHA, a common food additive, may promote deleterious health effects in the lung.
Taurocholate uptake by membrane vesicles prepared from ileal brush borders

Abstract Taurocholate uptake by vesicles prepared from brush borders obtained from the small intestines of guinea pigs was studied. Vesicles obtained from the brush borders of ileums demonstrated an enhanced initial uptake in those incubations where a sodium ion gradient (extravesicular sodium concentration greater than intravesicular) was present at the outset. With the dissipation of this sodium gradient the intravesicular concentration of taurocholate declined. This overshoot phenomenon was absent in parallel incubations of vesicles made from jejunal tissue. When the sodium chloride was replaced by isosmotic amounts of mannitol no overshoot was observed in incubations of ileal vesicles until subsequent addition of sodium chloride to these incubations. These observations are in accord with the idea that those subcellular structural elements operating in the ileal bile salt transport system are associated with the brush border membranes of the ileal mucosal cells.
Features of a seminal proteinase inhibitor- zona pellucida-binding component on murine spermatozoa.

Murine cauda epididymal sperm contain sites on the plasma membrane over the apical portion of the acrosome that recognize proteinase inhibitors and the homologous zona pellucida. Ten times more of the component can be extracted from cauda and ductus sperm than from equal numbers of caput and corpus sperm. Likewise, few sperm from the upper epididymal regions are able to bind seminal inhibitor, while the majority of sperm from the cauda and ductus do bind. Cauda epididymal and ductus sperm lose little of their ability to bind inhibitor after a 4-hour in vitro incubation in either a capacitating or a noncapacitating medium. The percentage of naturally inseminated sperm with the seminal inhibitor bound to their surface decreases to about 10 after 4 hours in utero. Approximately 80% of these sperm show positive fluorescence when given the opportunity to rebind the inhibitor, and these sperm do have an intact plasma membrane over the apical portion of the acrosome. Furthermore, after 4 hours in utero, the inhibitor bound in the same region of the sperm head as it did on freshly ejaculated sperm. The seminal inhibitor inhibits the binding of sperm to the zona if added during the first 15 minutes of incubation but has no effect on attachment. The data indicate that sperm gain the ability to bind the seminal inhibitor during the epididymal sojourn. Furthermore, this binding capacity is not lost during in vitro or in utero incubation. The site is not involved in sperm-zona attachment but does participate in the binding of sperm to the zona.
Enjoyment and consumption of defiant rock music as a function of adolescent rebelliousness

Trait rebelliousness and enjoyment of defiant or nondefiant rock music videos were assessed in male and female high school students. Data were analyzed in a 2 X 2 X 2 mixed‐measures design, with subject rebelliousness (low, high) and gender as independent‐measures factors and defiance expressed in rock music (absent, present) as a repeated‐measures factor. Rebellious male students outnumbered rebellious female students by a factor of three. Counter to expectations, highly rebellious students did not enjoy defiant rock videos more than did their less rebellious peers, nor did they consume more defiant rock music than did their peers. Highly rebellious students enjoyed rock videos devoid of defiance significantly less than did their peers, and they consumed significantly less nondefiant rock music than did their peers. Rebellious youths, then, appear to be partial to defiance as a salient theme in rock music, mostly by avoiding rock that is devoid of this theme.
Relative Movement Of The α-Subunit's First And Last External Loops Throughout Na/K-Pump Cycle

Structural models of the Na/K-pump α-subunit show that conserved residues D121 (loop 1-2, pig-α1 numbering) and R972 (loop 9-10) are 5-7 A apart in E2, and more than 12 A away in E1. To check whether these residues reach conformation-dependent atomic proximity, the substitutions D121C and R972C were introduced (individually and concurrently) into the ouabain-insensitive C104Y-Xenopus-α1. Each mutant was coexpressed with Xenopus-β3 in Xenopus oocytes and their function tested in Na+-loaded oocytes under two-electrode voltage clamp. K+o-activated Na/K-pump currents were observed in oocytes injected with D121C or R972C, but not in those injected with D121C-R972C, unless the eggs were exposed to TCEP (10-50 mM, ∼20 min), consistent with the presence of a pump-inhibiting disulfide.To identify the conformation locked by the disulfide, we used palytoxin to transform Na/K-pumps into channels. Palytoxin-induced currents (IPTX) in outside-out patches from oocytes expressing D121C-R972C, bathed in Na+ solutions, were insensitive to MTSET+ application. Patch exposure to DTT restored MTSET+-sensitivity (∼65% IPTX reduction) without affecting IPTX amplitude. Palytoxin stabilizes an E2P-like structure; thus, the lack of DTT effect on IPTX suggest that cross-linking between D121C and R972C occurs in E2P, with the external cation pathway open. Moreover, pump inhibition by spontaneous disulfide formation indicates that conformational mobility between these residues is required for the E2 to E1 transition.The slow component of ouabain-sensitive transient charge movement in 125 mM Nao+ was measured in Na+-loaded oocytes expressing these mutants. The center of the equilibrium distribution of charge (voltage of equal occupancy of E1 and E2) for R972C (V1/2= -34±8 mV) was identical to that of the C104Y-α1 template (V1/2= -35±3 mV). Therefore, it appears that a D121-R972 salt bridge is not necessary for E2P stabilization among Na+-occupied states.
Cognition and adjustment among children of separated or divorced parents

The current study tested the hypothesis that coping with stress is associated with the individual's cognitive appraisals of the stressor and of their resources for coping with the stressor. Fifty-two children between 8.5 and 12 years of age who were experiencing the separation or divorce of their parents were given a measure of appraisals of divorce and a measure of appraisals of coping options. Their parents and teachers filled out behavior checklists, and teachers reported their classroom grades. For boys, appraisals of divorce situations were related to behavior in the home but not in the school. Boys' adaptive appraisals tended to be more strongly associated with behavior than were maladaptive appraisals. Their appraisals of coping options were related to personal adjustment in both the home and the school, but not to academic performance. For girls, only a few of the relationships between cognition and psychosocial adjustment were significant, possibly because of their restricted range of grades and scores on the behavior checklists. These findings provide partial support for the prediction that coping is related to appraisals of stressful events and of one's resources for coping with the events.
Comparison of three methods of maintaining a sterile injectate system during cardiac output determinations

Abstract Current technique for determining cardiac output involves multiple manipulations of the injectate system and thereby raises the potential for serious infection. A randomized crossover study was undertaken to compare three methods for determining cardiac outputs, focusing on (1) ability to maintain sterile injectate, (2) operator time, and (3) cost effectiveness. The methods compared were the closed-loop injectate delivery, capped-syringe, and double-bag systems. Forty-five subjects were randomly assigned to one of three methods used, then “crossed over” to an alternate method. This resulted in six different groups: (1) 15 subjects assigned to closed loop first, then crossed over to double bag (eight) or capped syringe (seven), (2) 15 subjects assigned to double bag first, then crossed over to closed loop (seven) or capped syringe (eight), and (3) 15 subjects assigned to capped syringe first, then crossed over to double bag (seven) or closed loop (eight). Quantitative cultures of sample injectates served as indicators of contamination. The Wilcoxon signed rank analysis showed no statistical difference (p > 0.9) in patient or catheter caracteristics between treatment groups. None of 30 cultures from the closed-loop method yielded bacterial growth, compared to 6 of the 30 cultures positive from each of the other methods (p
Steroid-induced remission in primary malignant lymphoma of the central nervous system

A case of primary malignant lymphoma of the central nervous system is described in which lesions seen on computed tomography scans disappeared, and clinical remissions occurred with the administration of corticosteroids. The tumor affected the region of the fourth ventricle and parietal and frontal lobes. In our patient, three remissions occurred over a span of 24 months, each in conjunction with corticosteroid administration. This supports other observations that steroids alter the natural history of primary malignant lymphoma of the central nervous system, leading to both radiologic and clinical remissions.
Functional characterization of the GDEP promoter and three enhancer elements in retinoblastoma and prostate cell lines

GDEP (gene differentially expressed in prostate cancer aka. PCAN1), a newly discovered gene with remarkable tissue specificity, is a promising candidate for regulatory analysis because it exhibits a high level of expression that is limited to two tissues, the retina and the prostate. As these two tissues have different origins and disparate functions it is likely that the regulatory mechanisms responsible for expression are not shared in their entirety. In addition, both the retina and prostate are prime targets for gene therapy. To date there have been no functional studies of the GDEP promoter. Therefore to understand tissue-specific expression of GDEP we constructed promoter expression constructs. To further characterize functional regulatory regions within the GDEP gene, we investigated potential regulatory components for tissue-specific expression in the 40 kb intron of this gene. We have identified a 1.5 kb prostate-specific promoter from the proximal region of the GDEP gene. A smaller 0.5 kb promoter exhibited minimal activity in the retinoblastoma cell line Y79, but not in the prostate cells tested. In addition we have investigated three enhancer elements located in the 40 kb intron of the GDEP gene. We identified two enhancer elements that increase reporter gene expression in prostate cell line LNCaP and one additional enhancer element that increases expression in the Y79 cell line approximately 8-fold making it a strong retinal-specific enhancer.
Putting Geography Education into Place: What Geography Educators Can Learn from Place-Based Education, and Vice Versa.

In recent years, geography educators have sought to make their pedagogy relevant to pressing social and environmental issues, but these efforts have largely imported pedagogies from outside of geography. In place-based education, in contrast, place—one of geography’s defining themes—serves as a central organizing principle for a socially relevant pedagogy. This article reviews the pedagogy of place-based education and compares it to current practices in geography education. The argument is that integrating the approaches of place-based education can make geography education more relevant and that a geographic perspective can help place-based education programs more effectively promote social justice and environmental sustainability.
The Effects of Color Cues on Typically Developing Preschoolers' Speed of Locating a Target Line Drawing: Implications for Augmentative and Alternative Communication Display Design

Purpose This research examined how the presence of color in relation to a target within an augmentative and alternative communication array influenced the speed with which typically developing preschoolers located a target line drawing. Method Fifteen children over the age of 4 years (from 4;2 [years;months] to 5;4) and 15 children under the age of 4 years (2;10–3;11) participated. Participants were asked to find a target line drawing of foods (e.g., banana and tomato) among an array of 12. The reaction time of locating the target was measured across 4 conditions in which the foreground color and the background color of the line drawing were manipulated. Results For all participants, line drawings featuring foreground color provided greater advantages in the speed of locating the target compared with drawings featuring only background color. Younger participants demonstrated faster reaction times when color was limited to the foreground. Conclusion Clinicians should consider incorporating color in the for...
Engineered nanoparticles as precise drug delivery systems

With the remarkable development of nanotechnology in recent years, new drug delivery approaches based on the state-of-the-art nanotechnology have been receiving significant attention. Nanoparticles, an evolvement of nanotechnology, are increasingly considered as a potential candidate to carry therapeutic agents safely into a targeted compartment in an organ, particular tissue or cell. These particles are colloidal structures with a diameter smaller than 1,000 nm, and therefore can penetrate through diminutive capillaries into the cell's internal machinery. This innovative delivery technique might be a promising technology to meet the current challenges in drug delivery. When loaded with a gene or drug agent, nanoparticles can become nanopills, which can effectively treat problematical diseases such as cancer. This article summarizes different types of nanoparticles drug delivery systems under investigation and their prospective therapeutic applications. Also, this article presents a closer look at the advances, current challenges, and future direction of nanoparticles drug delivery systems.
Replication of the Adjustment Scales for Children and Adolescents core syndrome factor structure

Independent examination and replication of the core syndrome factor structure of the Adjustment Scales for Children and Adolescents (ASCA; McDermott, Marston, & Stott, 1993) is reported. A sample of 1,020 children were randomly selected from their classroom and rated on the ASCA by their teacher. The six ASCA core syndromes produced a two-factor solution through principle axis analysis using multiple criteria for the number of factors to extract and retain. Varimax, direct oblimin, and promax rotations produced identical results and nearly identical factor structure coefficients. It was concluded that the ASCA indeed measures two independent dimensions of psychopathology (Overactivity and Underactivity) that are similar to the conduct problems/externalizing and withdrawal/internalizing dimensions commonly found in the child psychopathology assessment literature (Cicchetti & Toth, 1991; Quay, 1986). © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 191–199, 2004.