cssi/SciSciGPT-SciSciNet huggingface dataset:
Quorum Signaling and Symbiosis in the Marine Luminous Bacterium Vibrio fischeri

This chapter reviews the role of quorum sensing in Vibrio fischeri, focusing on recent developments in one's understanding of the genetics and physiology of cell-cell signaling by populations of these bacteria, both in culture and in their light-organ symbioses. Particular emphasis is placed on outlining the regulatory factors and pathways by which quorum sensing coordinates the biological activities of this bioluminescent microbe. Early work showed that V. fischeri strains native to Euprymna scolopes were especially well adapted to this host and that nonnative strains such as MJ1 did not colonize juvenile squid well; thus, MJ1 was not an appropriate strain for studying the symbiosis between V. fischeri and E. scolopes. Production of N-octanoyl-homoserine lactone (C8-HSL) initiates stimulation of the lux operon at moderate cell densities; if ES114 had relatively low expression of AinS and low C8-HSL output, this deficiency could potentially explain why ES114 is so much dimmer than MJ1. Most likely, then, the large difference in the levels of N-3-oxo-hexanoyl-homoserine lactone (3-O-C6-HSL) production and luminescence seen between cultures of ES114 and MJ1 is due to external regulatory influences on the autoinducer synthase genes, and such regulation may be multifactorial. Biochemical and genetic studies of Acyl-homoserine lactone (AHL) signaling in Vibrio harveyi have shown that, in the presence of an inducing concentration of the LuxM-synthesized AHL, the receptor, LuxN,participates in a phosphorelay cascade by stimulating the relative dephosphorylation of LuxU.
Memory: Anatomical Organization of Candidate Brain Regions

The sections in this article are: 1 Relationship Between Association Cortices and Medial Temporal Lobe 2 Anatomy of Hippocampal Formation 2.1 Species Differences 2.2 Nomenclature 2.3 Subdivisions 2.4 Intrinsic Circuitry 2.5 Hippocampal Topography 2.6 Extrinsic Connections 2.7 Immunohistochemical Studies of Neuroactive Substances 3 Anatomy of Mamillary Complex 3.1 Intrinsic Organization 3.2 Afferents 3.3 Efferents 3.4 Connections of Associated Nuclei 4 Anatomy of Amygdaloid Complex 4.1 Nomenclature and Subdivisions 4.2 Intrinsic Circuitry 4.3 Extrinsic Connections 4.4 Neuroactive Substances 5 Comparison of Organization of Amygdaloid Complex and Hippocampal Formation 6 Anatomy of Mediodorsal Nucleus of Thalamus 6.1 Intrinsic Organization 6.2 Cortical Connections 6.3 Subcortical Connections 7 Neuropathology of Memory-Related Structures in Alzheimer's Disease 7.1 Hippocampal Formation 7.2 Amygdaloid Complex 7.3 Mamillary Complex and Mediodorsal Thalamus 7.4 Loss of Neuroactive Substances in Alzheimer-Affected Hippocampal Formation 8 Temporal Stem Hypothesis Revisited 9 Are There Additional Candidate Structures?
Empirical relations between magnetic fluxes and atmospheric radiative losses for cool dwarf stars

We derive and discuss relations between magnetic, X-ray, and Ca II H+K flux densities for a sample of G, K, and M dwarfs.
Phase Relations of the SrO–Ho2O3–CuOx System

Abstract The phase diagram of the SrO– R 2 O 3 –CuO x system, where R =Ho, was investigated in air. The tie-line relationships of the system were determined. The Sr analog of the high T c superconductor Ba 2 HoCu 3 O 6+ x was not observed in this system. Two ternary phases were found, namely, the “14–24” solid solution Sr 14− x Ho x Cu 24 O 41 and the “green phase” SrHo 2 CuO 5 . Holmium was found to substitute for the Sr site in the solid solution Sr 14− x Ho x Cu 24 O 41 up to the value of x ≈5. The melting temperature range of this solid solution is from 975 to 1025°C, for x =0 to x =5, respectively. The green phase is isostructural to its Ba analog, BaHo 2 CuO 5 , and is orthorhombic with space group Pbnm and cell parameters a =7.0971(13) A, b =12.0262(23) A, and c =5.5849(12) A. A comparison of the Ho system with reported systems of R =La, Nd, and Y indicated that a trend exists. The larger the lanthanide ions, the more complicated the phase diagrams, i.e., with a greater number of ternary phases/solid solutions. Despite similar ionic radii between Ho 3+ and Y 3+ , the phase diagrams of these two systems are rather different. The green phase SrHo 2 CuO 5 is not stable in the Y system.
Intraoperative approaches for deep brain stimulation and targeting

Publisher Summary This chapter reviews that the intraoperative procedures for extrapyramidal disorders have expanded in methodology and patient diagnoses. Imminent further expansion is seen for a variety of basal ganglia disorders that involve both motor and non-motor dysfunction. Accompanying this proliferation in applications are new requirements for coordinating teams in and out of the operating theater to maximize benefits and avoid complications. The chapter focuses on those neurophysiologic techniques applied intraoperatively that include high- and low-technology approaches alike. It discusses that the need for physiologic mapping belies the resolution limitations of radiographic imaging, the errors in stereotactic localization, and the clear fact that anatomy does not always predict physiology. Indeed, the ideal anatomic locale to produce maximal clinical benefit for thalamus procedures and subthalamic nucleus (STN) procedures continue to be refined. The chapter reviews that the efficiency of experienced teams minimizes the routine time required and typically those cases that require more extensive microelectrode recording mappings have radiographic localization with poorer outcomes.
To Be or Not to Be… a Profession: Management Education and Its Discontents.

The author discusses the criticisms directed at management education and argues that the causes of today's problems are rooted in the apparent disconnect between management academics and practitioners. It starts with an examination of management education and its discontents from past to present. Then, existing problems are analyzed in the categories of (a) relevance, (b) analytical versus soft skills, and (c) legitimacy. It is asserted that the problems can be overcome when management scholars and practitioners reconcile and exert their joint efforts on redefining management as a professional discipline. Suggestions are offered as to how to carry out this endeavor.
Wissenschaftliche Bibliothekarinnen und Bibliothekare als Opfer der NS-Diktatur. Eine Übersicht über 250 Lebensläufe seit dem Jahr 1933. Teil 1: Die Entlassungen

Bisher ist nicht bekannt, wie viele Personen 1933-1945 im Bibliothekswesen innerhalb des deutschen Machtbereichs Opfer der NS Diktatur geworden sind. In zweijahrigen Recherchen konnten jetzt 250 (vor allem wissenschaftliche) Bibliothekarinnen und Bibliothekare ermittelt werden, die in Deutschland, in Osterreich und in den durch deutsche Truppen besetzten Landern Opfer dieser Diktatur wurden. Teil 1 des Beitrags stellt vier Listen mit 243 entlassenen Personen und den Bibliotheken vor, in denen sie tatig waren. 89 von ihnen waren Mitglieder im Verein Deutscher Bibliothekare (VDB). Zahlreiche Beispiele stellen die Grunde fur die Entlassungen und deren praktische Durchfuhrung vor.Up to now it hasn’t been known exactly how many librarians became victims of the Nazi regime between 1933 and 1945 in the area of German control. As a result of a two-year research, 250 (mostly academic) librarians were identified who became victims of the regime in Germany, Austria and in the occupied countries. The first part of the paper presents four lists containing 243 persons who were dismissed from their libraries. 89 of them were members of the Association of German Librarians (VDB). Numerous examples show how the dismissals were motivated and executed.
Rising motion of a swarm of drops in a linearly stratified fluid

Abstract Direct numerical simulations of a swarm of deformable drops rising in density stratified fluids are presented at intermediate Reynolds numbers. All flow scales are fully resolved using front-tracking/finite-volume method. The average rise velocity and velocity fluctuations of the swarm are reduced in the presence of density stratification. The isotropy in velocity fluctuations is enhanced as the volume fraction increases. The higher likelihood of the cluster formation is illustrated in the presence of density stratification and is explained by quantitative assessment of the microstructure using radial and angular pair probability distribution functions. The combined effect of the drop deformability and density stratification on the average deformation of the drops is investigated.
Inactivation of cyclic GMP-dependent protein kinase by Nα-tosyl-L-lysine chloromethylketone☆

Abstract Cyclic GMP-dependent protein kinase from bovine lung and cyclic AMP-dependent protein kinase from bovine heart are inactivated by Nα-tosyl-L-lysine chloromethylketone (TLCK) in the presence of cyclic GMP and cyclic AMP, respectively. The inactivation of both protein kinases is pseudo-first order, suggesting the rate limiting step is beyond the binding of TLCK. Cyclic GMP-dependent protein kinase is inactivated less than 1 4 as rapidly as cyclic AMP-dependent protein kinase, although it shows a higher apparent affinity for TLCK. Cyclic AMP stimulated the rate of inactivation of cyclic AMP-dependent protein kinase 10-fold but cyclic GMP stimulated the rate of inactivation of cyclic GMP-dependent protein kinase only 1.5-fold. The rate of inactivation of cyclic GMP-dependent protein kinase by TLCK is sufficiently rapid (half-time of about 30 min at 37°C with 2 mM TLCK) to account for the effects of TLCK on cell growth observed by others.
Functional Consequences of a Mutation in an Expressed Human α-Cardiac Actin at a Site Implicated in Familial Hypertrophic Cardiomyopathy

Abstract Point mutations in human α-cardiac actin cause familial hypertrophic cardiomyopathy. Functional characterization of these actin mutants has been limited by the lack of a high level expression system for human cardiac actin. Here, wild-type (WT) human α-cardiac actin and a mutant E99K actin have been expressed and purified from the baculovirus/insect cell expression system. Glu-99 in subdomain 1 of actin is thought to interact with a positively charged cluster located in the lower 50-kDa domain of the myosin motor domain. Actin-activated ATPase measurements using the expressed actins and β-cardiac myosin showed that the mutation increased the Km for actin 4-fold (4.7 ± 0.7 μm for WT versus 19.1 ± 3.0 μm for the mutant), whereas the Vmax values were similar. The mutation slightly decreased the affinity of actin for S1 in the absence of nucleotide, which can partly be accounted for by a slower rate of association. The in vitro motility for the E99K mutant was consistently lower than WT over a range of ionic strengths, which is likely related to the lower average force supported by the mutant actin. The thermal stability of the E99K was comparable to that of WT-actin, implying no folding defects. The lower density of negative charge in subdomain 1 of actin therefore weakens the actomyosin interaction sufficiently to decrease the force and motion generating capacity of E99K actin, thus providing the primary insult that ultimately leads to the disease phenotype.
Upwind-Difference Potentials Method for Patlak-Keller-Segel Chemotaxis Model

We develop a novel upwind-difference potentials method for the Patlak-Keller-Segel chemotaxis model that can be used to approximate problems in complex geometries. The chemotaxis model under consideration is described by a system of two nonlinear PDEs: a convection-diffusion equation for the cell density coupled with a reaction-diffusion equation for the chemoattractant concentration. Chemotaxis is an important process in many medical and biological applications, including bacteria/cell aggregation and pattern formation mechanisms, as well as tumor growth. Furthermore modeling of real biomedical problems often has to deal with the complex structure of computational domains. There is consequently a need for accurate, fast, and computationally efficient numerical methods for different chemotaxis models that can handle arbitrary geometries. The upwind-difference potentials method proposed here handles complex domains with the use of only Cartesian meshes, and can be easily combined with fast Poisson solvers. In the numerical tests presented below we demonstrate the robustness of the proposed scheme.
A Single Site (Ser16) Phosphorylation in Phospholamban Is Sufficient in Mediating Its Maximal Cardiac Responses to β-Agonists

Phospholamban (PLB) can be phosphorylated at Ser16 by cyclic AMP-dependent protein kinase and at Thr17 by Ca2+-calmodulin-dependent protein kinase during β-agonist stimulation. A previous study indicated that mutation of S16A in PLB resulted in lack of Thr17 phosphorylation and attenuation of the β-agonist stimulatory effects in perfused mouse hearts. To further delineate the functional interplay between dual-site PLB phosphorylation, we generated transgenic mice expressing the T17A mutant PLB in the cardiac compartment of the null background. Lines expressing similar levels of T17A mutant, S16A mutant, or wild-type PLB in the null background were characterized in parallel. Cardiac myocyte basal mechanics and Ca2+ kinetics were similar among the three groups. Isoproterenol stimulation was associated with phosphorylation of both Ser16 and Thr17 in wild-type PLB and Ser16 phosphorylation in T17A mutant PLB, whereas there was no detectable phosphorylation of S16A mutant PLB. Phosphorylation of Ser16 alone in T17A mutant PLB resulted in responses of the mechanical and Ca2+ kinetic parameters to isoproterenol similar to those in wild-type myocytes, which exhibited dual-site PLB phosphorylation. However, those parameters were significantly attenuated in the S16A mutant myocytes. Thus, Ser16 in PLB can be phosphorylated independently of Thr17 in vivo, and phosphorylation of Ser16 is sufficient for mediating the maximal cardiac responses to β-adrenergic stimulation.
Phosphorylation modulates calpain-mediated proteolysis and calmodulin binding of the 200-kDa and 160-kDa neurofilament proteins.

: The effects of enzymatic dephosphorylation on neurofilament interaction with two calcium-binding proteins, calpain and calmodulin, were examined. Dephosphorylation increased the rate and extent of 200-kDa neurofilament protein proteolysis by calpain. In contrast, dephosphorylation of the 160-kDa neurofilament protein did not alter the rate or extent of calpain proteolysis. However, the calpain-induced breakdown products of native and dephosphorylated 160-kDa neurofilament protein were different. Dephosphorylation did not change the proteolytic rate, extent, or breakdown products of the 68-kDa neurofilament protein. Calmodulin binding to the purified individual 160- and 200-kDa neurofilament proteins was increased following dephosphorylation. These results suggest that phosphorylation may regulate the metabolism and function of neurofilaments by modulating interactions with the calcium-activated proteins calpain and calmodulin.
Surgery for atypical scoliosis

Purpose of review Atypical scoliosis poses challenges for recognition and medical and surgical management. Recent technological advances in spine surgery provide new opportunities for application to atypical deformity. Recent findings Marfan syndrome must be recognized for proper cardiovascular management. Spinal challenges include early deformity, poor response to bracing, increased blood loss, thin pedicles, risk of cerebrospinal fluid leak, and failure of fixation and adding-on. Neurofibromatosis presents large curves at an early age. Dystrophic apices may present thin pedicles and consequent difficulties of fixation. Anterior surgery should be considered if kyphosis and/or dystrophic curves cannot be corrected. Syringomyelia should be considered in early-onset or left-main thoracic scoliosis, or patients with subtle neurologic findings. Curves less than 45° may stabilize with neurosurgical treatment of the syrinx itself. About 10% of patients with Charcot–Marie–Tooth disorder will have scoliosis. Spinal cord monitoring may be unpredictable. Scoliosis in patients with Ehlers–Danlos syndrome should be approached primarily posteriorly. Summary Newer principles of spinal deformity can produce significant improvements in management of atypical deformity.
Obtaining mode mixity for a bimaterial interface crack using the virtual crack closure technique

We review, unify and extend work pertaining to evaluating mode mixity of interfacial fracture utilizing the virtual crack closure technique (VCCT). From the VCCT, components of the strain energy release rate (SERR) are obtained using the forces and displacements near the crack tip corresponding to the opening and sliding contributions. Unfortunately, these components depend on the crack extension size, Δ, used in the VCCT. It follows that a mode mixity based upon these components also will depend on the crack extension size. However, the components of the strain energy release rate can be used for determining the complex stress intensity factors (SIFs) and the associated mode mixity. In this study, we show that several—seemingly different—suggested methods presented in the literature used to obtain mode mixity based on the stress intensity factors are indeed identical. We also present an alternative, simpler quadratic equation to this end. Moreover, a Δ-independent strain energy release based mode mixity can be defined by introducing a “normalizing length parameter.” We show that when the reference length (used for the SIF-based mode mixity) and the normalizing length (used for Δ-independent SERR-based mode mixity) are equal, the two mode mixities are only shifted by a phase angle, depending on the bimaterial parameter e.
Recovery of Salmonella Derby From Inoculated Egg Shell Surfaces Following Sanitizing

Abstract THE incrimination of eggs and egg products in recent outbreaks of human salmonellosis makes it imperative to find methods to control Salmonella contamination of these foods. If this contamination of eggs with salmonellae is external and not internal (Mundt and Tugwell, 1958; Ross et al., 1964; and Mellor and Banwart, 1965), sanitizing the egg shell surface shortly after lay may be one method of effective control. Salmonella surface contamination, if given time and/or the proper conditions, can penetrate into the egg (Stokes et al., 1956; Mellor, 1965). Natural barriers resist this penetration (Walden et al., 1956; Hartung and Stadelman, 1963; and Lifshitz et al., 1964), but do not prevent it. If shell surface contamination were removed prior to invasion, the egg content should remain essentially sterile. Earlier efforts in washing and sanitizing eggs were mainly concerned with the problem of spoilage or the control of avian diseases (Brooks and Taylor,…
Cancer Risk Elicitation and Communication: Lessons from the Psychology of Risk Perception

Cancer risk perceptions are a key predictor of risk-reduction practices, health behaviors, and processing of cancer information. Nevertheless, patients and the general public (as well as health care providers) exhibit a number of errors and biases in the way they think about risk, such that their risk perceptions and decisions deviate greatly from those prescribed by normative decision models and by experts in risk assessment. For example, people are more likely to engage in screening behaviors such as mammography when faced with loss-based messages than gain-framed messages, and they often ignore the base rate of a given disease when assessing their own risk of obtaining this disease. In this article, we review many of the psychological processes that underlie risk perception and discuss how these processes lead to such deviations. Among these processes are difficulties with use of numerical information (innumeracy), cognitive processes (eg, use of time-saving heuristics), motivational factors (eg, loss and regret aversion), and emotion. We conclude with suggestions for future research in the area, as well as implications for improving the elicitation and communication of personal cancer risk.
Look Closely and You Will See, Listen Carefully and You Will Hear: Urban Design and Social Interaction on Streets

Streets represent a significant part of the public space in urban areas and cater to our functional, social and leisure needs. The biggest competitive advantage of the neighbourhood commercial street is its ability to support social interaction as a part of the daily routine. Numerous characteristics have been previously associated with good urban design of the street. This paper emphasizes the need for researchers to view the experience of the street especially from the users' perspective. Using extensive behaviour mapping and user interviews this paper focuses on identifying the specific characteristics that support social interaction on neighbourhood commercial streets. The findings expand our understanding of what we consider the realm of design and suggest specific physical and land-use characteristics, and their management that are important in supporting social interaction on neighbourhood commercial streets.
Competency-Based Hiring, Job Description, and Performance Goals: The Value of an Integrated System

ABSTRACT Over the past 15 years, the work of staff at the University of Arizona (UA) Libraries has transformed significantly to meet the evolving needs of library users, the changing profession, and the economic climate. To keep pace with these changes, the UA Libraries have gradually shifted to a new, competency-based hiring and performance management model. This article will describe the process of moving to a competency-based model both for librarians and classified staff at the University of Arizona.
Thyroidal Iodide Transport. VIII. Relation Between Transport, Goitrogenic and Antigoitrogenic Properties of Certain Anions

1. Maximal goiter production was compared in rats fed low iodine diets containing various antithyroid anions. Even though no significant organic iodine formation occurred, goiters resulting from the feeding of ReO4-, ClO4, BF4 or NOT weighed 20–25 mg/100 g body weight, whereas goiters produced with propylthiouracil were nearly twice as large (40–45 mg/100 g). SCN- was intermediate between these groups. Thyroidal iodine depletion and serum PBI depression were equal in all groups. No histological differences could be established. The ability to produce a certain degree of thyroid enlargement is a function of the K1 for I- transport in thyroid slices. 2. ReO4 and C1O.T were antigoitrogenic when fed together with propylthiouracil, that is, goiters were reduced to a size approaching that following anion treatment alone. This antigoitrogenic effect occurred at lower doses than the goitrogenic effect. 3. Circulating TSH levels were not depressed when ReO or ClO4 was fed with propylthiouracil. While there appeare...
Nonlocal generalized angular-momentum balance laws and equations of motion

Abstract It is shown how systems of nonlocal (i.e. integrodifferential) linear second-order equations of motion (LSIDEs) can be directly related to associated nonlocal angular-momentum complexes as well as to balance laws corresponding to such complexes. This gives one the freedom to obtain balance laws from given LSIDEs or vice versa. These laws will, as usual, augment the equations of motion as further useful information about the physical system. Under certain conditions one then sees how the balance laws reduce to corresponding conservation laws. Two examples, sketched to indicate how the formalism can be applied, come from continuum mechanics and quantum mechanics for physical systems described by nonlocal interactions. A third example is from quantum field theory for the case of local interactions for particles of arbitrary integral spin in general, and for electromagnetism in particular. The formalism can thus be appled to physical systems whose equations of motion may be relativistic and either classical or quantum mechanical.
Fibrosing mesenteritis simulating pelvic carcinomatosis

A case of fibro-inflammatory thickening of the mesosigmoid simulating pelvic carcinomatosis on barium enema and ultrasound examination is presented. Histologic features of this case and cases of retractile mesenteritis and mesenteric panniculitis are discussed.
Combined mitochondrial and nuclear sequences support the monophyly of forcipulatacean sea stars.

Abstract Previous molecular phylogenetic analyses of forcipulatacean sea stars (Echinodermata: Asteroidea) have reconstructed a non-monophyletic order Forcipulatida, provided that two or more forcipulate families are included. This result could mean that one or more assumptions of the reconstruction method was violated, or else the traditional classification could be erroneous. The present molecular phylogenetic analysis included 12 non-forcipulatacean and 39 forcipulatacean sea stars, with multiple representatives of all but one of the forcipulate families and/or subfamilies. Bayesian analysis of approximately 4.2 kb of sequence data representing seven partitions (nuclear 18S rRNA and 28S rRNA, mitochondrial 12S rRNA, 16S rRNA, 5 tRNAs and cytochrome oxidase I with first and second codon positions analyzed separately from third codon positions) recovered a consensus tree with three well-supported clades (78%–100% bootstrap support) that corresponded at least approximately to traditional taxonomic ranks: the superorder Forcipulatacea (Forcipulatida + Brisingida) + Pteraster, the Brisingida/Brisingidae and Asteriidae + Rathbunaster + Pycnopodia. When a molecular clock was enforced, the partitioned Bayesian analysis recovered the traditional Forcipulatacea. Five of six genera represented by two or more species were monophyletic with 100% bootstrap support. Most of the traditional subfamilial and familial groupings within the Forcipulatida were either unresolved or non-monophyletic. The separate partitions differed considerably in estimates of model parameters, mainly between nuclear sequences (with high GC content, low rates of sequence substitution and high transition/transversion rate ratios) and mitochondrial sequences.
Safety and effectiveness of ticarcillin plus clavulanate potassium in treatment of lower respiratory tract infections

Abstract The safety and effectiveness of ticarcillin plus clavulanate potassium was evaluated in an open study of 43 patients with community-acquired lower respiratory tract infections. The mean age of the 28 patients in whom bacteriologic evaluations were possible was 55 years; at least two thirds of the patients had a history of alcoholism or chronic obstructive pulmonary disease. A pathogen was isolated from sputum samples in 23 patients; five of these 23 also had documented bacteremia. There were five additional cases of bacteremia associated with clinical signs and symptoms of pneumonia but with no organisms isolated from sputum cultures. Thirty-five pathogens were isolated from the 33 evaluable infection sites, primarily Streptococcus pneumonlae and Hemophilus influenzae. S. pneumoniae was the causative organism in all 10 cases of bacteremia. Ticarcillin plus clavulanate potassium (3 g of ticarcillin and 100 mg of clavulanic acid) was administered intravenously for a mean of six days. All 35 organisms isolated before treatment were eradicated. In one patient a superinfection with Pseudomonas aeruginosa developed after treatment with ticarcillin plus clavulanate potassium. A clinical evaluation was possible for 32 of the 33 infection sites; clinical cure was achieved at 31 sites and improvement was seen at the other site. All 43 patients were monitored for adverse reactions by both clinical observation and laboratory tests. In one patient, reversible thrombocytopenia developed that required discontinuation of ticarcillin plus clavulanate potassium. In another patient, there was a slight decrease in the potassium level during therapy. No systemic adverse reactions occurred, nor was there any instance of local effects associated with the intravenous infusion of the drug.
SU-E-T-540: Comparison of CT and MRI Based Monte Carlo Simulation for Gamma Knife Stereotactic Radiosurgery

Purpose: MRI image is most frequently used for target contouring and treatment planning in Gamma Knife stereotactic radiosurgery (SRS). This study is to compare geometric and dosimetric accuracy of CT and MRI‐based Monte Carlo (M.C.) simulation for Gamma Knife SRS. Methods: A cylindrical water phantom with scale for MRI QA was scanned and the MRI images were transferred to a planning system for geometric analysis. M.C. simulation was applied on patient geometries reconstructed from CT and MRI data for dosimetric comparison. In the M.C. simulation, Gamma Knife (Model C) unit geometry and material were reconstructed according to original unit. A heterogeneous patient MRI geometry was created by putting a 1.8 g/cc skull in the unity homogeneous MRI geometry based on MRI anatomy knowledge. The dose was calculated using M.C. simulation in both homogenous and inhomogeneous CT and MRI geometries with identical beam parameters. The dose distribution was compared by overlapping the isodose‐lines for each calculation. The DVH was derived by collecting dose on a small volume around isocenter. Results: In MR image, the maximum errors along all directions are within 0.5 mm in the volume of interest (VOI) which is about 15cm high and 20cm diameter in x and y plane. There is no observable difference of relative isodose lines in CT and MRI geometries. However, the absolute dose in heterogeneous CT geometry was 3.2% lower than the dose in homogeneous CT geometry from the DVH comparison. The absolute dose in homogeneous MRI phantom was 3.3% higher that dose in heterogeneous CT geometry. After applying heterogeneity correction to the skull for MRI, the difference was reduced to less than 2%. Conclusion: MRI image distortion is small with the maximum distortion within 0.5mm in VOI. MRI‐based Monte Carlo planning for Gamma Knife is feasible after applying proper skull heterogeneity correction.
Effect of Percoll wash on sperm motion parameters and subsequent fertility in intrauterine insemination cycles

Purpose This study examined sperm motion parameters as measured by computerized automated semen analysis before and after a Percoll wash and determined if differences in any parameter were correlated with fertility subsequent to intrauterine insemination (IUI).
Essential Oil Mouthwash (EOMW) may be Equivalent to Chlorhexidine (CHX) for Long-Term Control of Gingival Inflammation but CHX Appears to Perform Better Than EOMW in Plaque Control

Article Title and Bibliographic Information Essential oils compared to chlorhexidine with respect to plaque and parameters of gingival inflammation: a systematic review. Van Leeuwen MPC, Slot DE, Van der Weijden GA. J Periodontol 2011 Feb;82(2):174-94. Epub 2010 Nov 2. Reviewer Anthony L. Neely, DDS, MDentSc, PhD Purpose/Question To determine whether essential oil mouthwash is comparable to chlorhexidine gluconate with respect to reducing plaque and gingival inflammation and promoting calculus accumulation and extrinsic staining Source of Funding Some support came from the Academic Center for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam Type of Study Design Systematic review with meta-analysis of data Level of Evidence Level 1: Good-quality, patient-oriented evidence Strength of Recommendation Grade Grade B: Inconsistent or limited-quality patient-oriented evidence
Do Race-Based Preferences Perpetuate Discrimination Against Marginalized Ethnic Groups?

Race-based preferential policies have been employed in the United States and other countries such as Malaysia, South Africa, Brazil, and India to foster economic development among economically marginalized ethnic groups. This research applies a two-player signaling model to help understand labor-market effects of race-based preferential policies used in college admissions. The model shows that in the context of imperfect information in the labor market, purely race-based forms of preferential policies in college admissions are likely to lead to statistical discrimination by future employers, reducing the equilibrium wage of targeted minority groups for both college graduates and non-college graduates. In addition, average wages of the targeted group remain unchanged in the model, with the targeted group being worse off to the extent that educational signaling is costly. In conclusion, the paper argues that race-base preferences cannot substitute for policies and programs that genuinely address imbalances in college preparation between ethnic groups.
Bacterial genetic methods to explore the biology of mariner transposons

Mariners are small DNA mediated transposons of eukaryotes that fortuitously function in bacteria. Using bacterial genetics, it is possible to study a variety of properties of mariners, including transpositional ability, dominant-negative regulation, overexpresson inhibition, and the function of cis-acting sequences like the inverted terminal repeats. In conjunction with biochemical techniques, the structure of the transposase can be elucidated and the activity of the elements can be improved for genetic tool use. Finally, it is possible to uncover functional transposase genes directly from genomes given a suitable bacterial genetic screen.
A Short History of the History of Objectivity

This article provides a broad overview of how American journalism historians have treated the concept of objectivity in the latter part of the 20th century. In following the narrative of objectivity's history, the author finds that historians’ narratives have shifted as intellectual attitudes toward objectivity have changed. Now that objectivity no longer plays as central a role in journalism as it once did, histories of the concept may shift once again.
THE RELATIONSHIPS BETWEEN SEASONAL VARIATION IN LIGHT INTENSITY, RAMET SIZE, AND SEXUAL REPRODUCTION IN NATURAL AND EXPERIMENTAL POPULATIONS OF ASTER ACUMINATUS (COMPOSITAE)

We conducted experiments to evaluate the effects of different patterns of seasonal light availability on ramet size and sexual reproduction in the understory herb, Aster acuminatus. In April 1982, 200 potted rhizomes were divided equally between a high light and a shaded site. Twice during the growing season subsets of pots were reciprocally transferred between the sites, resulting in eight different light treatments. There was significant variation among treatments in mean ramet weight (0.41-1.21 g), height (15.0-23.4 cm), number of flowers (0.o7.9) and percentage of ramets flowering ( 14-9 5). Periods of high light increased ramet height, weight, rhizome production and flowering, but high light earlier in the season increased ramet height more than did high light later in the season, while high light later had pronounced effects on the other three traits. Measurements taken in nine natural patches experiencing different patterns of seasonal light availability are consistent with the experimental results. The results provide new insights into the general phenomenon of size-dependent reproduction in herbs and illustrate
Volcanic winter and accelerated glaciation following the Toba super-eruption

Model calculations that investigate the possible climatic effects of the Toba volcanic cloud are presented. The increase in atmospheric opacity might have produced a 'volcanic winter', followed by a few years with maximum estimated annual hemispheric surface-temperature decreases of 3-5 C. The eruption occurred during the stage 5a-4 transition of the oxygen isotope record, a time of rapid ice growth and falling sea level. It is suggested that the Toba eruption may have greatly accelerated the shift to glacial conditions that was already under way, by inducing perennial snow cover and increased sea-ice extent at sensitive northern latitudes. As the onset of climate change may have helped to trigger the eruption itself, it is proposed that the Toba event may exemplify a more general climate-volcano feedback mechanism.
Stark-induced anapole magnetic fields in atoms.

We show that a paramagnetic atom with spin polarization S, in an electric field E, will have an anapole moment in the direction E\ifmmode\times\else\texttimes\fi{}S, with magnitude of order \ensuremath{\alpha}${\mathit{Ea}}_{0}^{4}$. There is a corresponding toroidal magnetic field inside the atom in the direction r\ifmmode\times\else\texttimes\fi{}(E\ifmmode\times\else\texttimes\fi{}S), with strength of order \ensuremath{\alpha}E. As an example, we evaluate exactly the toroidal field and its anapole moment for hydrogenic atoms to first order in E, using both the Schr\"odinger and Dirac equations. We also use the calculated electric polarizabilities to estimate the toroidal magnetic fields and anapole moments for the ground states of the alkali-metal atoms and for Rydberg states. We show that the Stark-induced toroidal magnetic fields of atoms will have no influence on their hyperfine structure. However, they can change the direction of the nuclear spins of electron-spin polarized molecules.
Gonadotropin-Releasing Hormone-Like Immunoreactivity in Rat Placenta

The concentration of gonadotropin-releasing hormone (GnRH) in the placenta, maternal plasma and fetal hypothalamus was measured in rats during days 13–21 of gestation. A substantial amount of GnRH was detectable in the extract of placenta and maternal plasma samples collected between days 13 and 21 and in the extract of fetal hypothalamus collected between days 19 and 21 of pregnancy. The GnRH level in the placenta and fetal hypothalamus, but not in plasma, fluctuated significantly during pregnancy. The level of GnRH gradually decreased in the placenta but increased in the fetal hypothalamus as the pregnancy proceeded. After gel filtration of placental extract, GnRH eluted in the same position as synthetic GnRH and hypothalamic GnRH. Dilution of placental extracts produced a displacement curve parallel to that of GnRH and hypothalamic extracts. These results indicate that GnRH is present in the placenta and that placental GnRH may have a role in the maintenance of pregnancy in rats.
Discovery of a new ATP-binding motif involved in peptidic azoline biosynthesis

Despite intensive research, the cyclodehydratase responsible for azoline biogenesis in thiazole/oxazole-modified microcin (TOMM) natural products remains enigmatic. The collaboration of two proteins, C and D, is required for cyclodehydration. The C protein is homologous to E1 ubiquitin-activating enzymes, whereas the D protein is within the YcaO superfamily. Recent studies have demonstrated that TOMM YcaOs phosphorylate amide carbonyl oxygens to facilitate azoline formation. Here we report the X-ray crystal structure of an uncharacterized YcaO from Escherichia coli (Ec-YcaO). Ec-YcaO harbors an unprecedented fold and ATP-binding motif. This motif is conserved among TOMM YcaOs and is required for cyclodehydration. Furthermore, we demonstrate that the C protein regulates substrate binding and catalysis and that the proline-rich C terminus of the D protein is involved in C protein recognition and catalysis. This study identifies the YcaO active site and paves the way for the characterization of the numerous YcaO domains not associated with TOMM biosynthesis.
Theory of constant proportion portfolio insurance

Abstract We study constant proportion portfolio insurance (CPPI), a dynamic strategy that maintains the portfolio's risk exposure a constant multiple of the excess of wealth over a floor, up to a borrowing limit. We use this simple rule to investigate how transaction costs and borrowing constraints affect portfolio insurance-type strategies. Absent transaction costs, CPPI is equivalent to investing in perpetual American call options, and is optimal for a piecewise-HARA utility function with a minimum consumption constraint. As the multiple increases, the payoffs under CPPI approach those of a stop-loss strategy. The expected holding-period return is not monotonic in the multiple, and a higher expected return can be obtained under CPPI than with a stop-loss strategy.
Dual receptor T cells extend the immune repertoire for foreign antigens.

Since the discovery of T cells that express two T cell receptors (TCRs), termed dual TCR cells, most studies have focused on their autoimmune potential, while their beneficial roles remained elusive. We identified, in normal mice, dual TCR cells that participated in the immune response to a foreign antigen. Unlike single TCR cells, dual TCR cells used the nonselected TCR to respond in the periphery, but relied on coexpression of a second TCR for intrathymic selection. We found that they were selected at low frequency in the naive repertoire, but dominated the response to antigen through clonal expansion. Thus, dual TCR cells can extend the TCR repertoire for foreign antigens by rescuing functional TCRs that cannot be selected on single TCR cells; they can, therefore, benefit the immune system.
Antiferroelectric-Ferroelectric Switching in a Simple “Kittel” Antiferroelectric

The intrinsic switching path for the electric field enforced transition from antiferroelectric to ferroelectric states has been computed for the simple Kittel linear antiferroelectric. The generalized switching curves give values of the polarization, free energy, and dielectric susceptibility as a function of applied field for a number of different antiferroelectric stabilities. The switching curves are qualitatively similar to those in real perovskite antiferroelectrics, and the possible extension of the treatment to real materials is discussed.
Mutationally altered 3′ ends of yeast CYC1 mRNA affect transcript stability and translational efficiency☆

The cyc1-512 mutant of the yeast Saccharomyces cerevisiae contains a 38 base-pair deletion in the 3' non-coding region of the CYC1 gene, which encodes iso-1-cytochrome c. The deletion affects the CYC1 terminator, causing CYC1 mRNAs to be much longer and more unstable than normal. Previous genetic analysis of revertants of the cyc1-512 mutant indicated that the defect could be completely or partially restored by three classes of genetic events: chromosomal rearrangements; local genetic changes near the original cyc1-512 mutation; and suppressors at unlinked loci. We show that all the revertants with chromosomal rearrangements have breakpoints 3' to the CYC1 locus, resulting in the formation of CYC1 mRNA with new 3' non-coding regions and new 3' mRNA termini. One spontaneous cyc1-512 revertant has a 3' insertion that resembles a repetitive, transposable yeast sequence (Ty1); CYC1 transcripts end just within the bounds of this element. This study reveals that the different 3' non-coding sequences, which arose by chromosomal rearrangements, increase the stability of CYC1 mRNA and have varying effects upon the mRNA translational efficiency. Many of the cyc1-512 revertants contain only local genetic changes that create stronger terminators from the weak terminators observed in the cyc1-512 mutant. Several types of terminators in these revertants have been identified; some cause discrete termination over a relatively small region, while others cause heterogeneous termination over a 200 base-pair region. The DNA sequence changes for two cyc1-512 revertants occur in a region with homology to a consensus sequence for transcription termination in yeast that was proposed by Zaret & Sherman (1982). Two classes of extragenic suppressors of the cyc1-512 mutation have been identified. One class of the suppressors appears specifically to enhance termination at weak terminator sites, while the other class of suppressors appears to increase the stability of aberrantly long CYC1 mRNA. The results from this study support our previous suggestion (Zaret & Sherman, 1982) that, in contrast to the usual situation in higher eukaryotes, transcription termination and polyadenylation may be coupled processes in yeast.
Proximity effect in gadolinium-backed lead films

Measurements of the surface reactance, at a frequency of 100 MHz and at various temperatures, have been used to study some aspects of the proximity effect in lead films in contact with gadolinium. It has been found that although the normal metal in this case is magnetic an adequate explanation of the experimental results cannot be obtained by assuming that the Ginzburg-Landau order parameter vanishes at theNS interface. The microscopic theory that allows the boundary condition (∇Ψ)n=Ψ/b (wheren indicates the normal component of the gradient, Ψ is the order parameter, andb is called the extrapolation length) does agree well with both the dependence of the transition temperatureTcNS on the thickness of the superconducting layer and variation of the surface reactance with temperature.
Role of the Nuclear Transport Factor p10 in Nuclear Import

The nuclear import factor p10 was cloned from Saccharomyces cerevisiae and found to be essential. The protein p10 can bind directly to several peptide repeat-containing nucleoporins. It also binds to the guanosine triphosphatase (GTPase) Ran in its guanosine diphosphate (GDP)-bound form and to karyopherin β. Assembly of the karyopherin heterodimer on immobilized nucleoporin yielded cooperative binding of p10 and Ran-GDP. Addition of GTP to this pentameric complex led to dissociation of karyopherin α, presumably via in situ formation of Ran-GTP from Ran-GDP. Thus, p10 appears to coordinate the Ran-dependent association and dissociation reactions underlying nuclear import.
Cells to Surgery Quiz: June 2014

QUESTIONS 1. A 54-year-old white man presents with the lesion shown above on his left lower arm and a similar-appearing lesion on his left upper back. There is no regional lymphadenopathy, and he is otherwise asymptomatic. Histopathologic and immunohistochemical analyses of the lesion shown are consistent with a primary melanoma with a thickness of 2.40 mm. The lesion on the patient’s back reveals findings concerning for a possible metastatic melanoma to the skin with a thickness of 3.20 mm. Which of the following is a tumor-produced extracellular matrix protein that could help distinguish a metastatic melanoma to the skin from a second primary melanoma and guide further workup for this patient?
Serum Proteins in NZB/B1 and Related Strains of Mice.∗:

SummarySerum gamma globulin levels of young NZW and NZB-NZC mice were found to be similar to those of 4 control inbred strains. Serum gamma globulin levels of young NZC and NZB-NZW mice were somewhat higher than those of the controls, whereas the levels were significantly higher in young NZB mice. In all strains studied the gamma and beta globulin levels were significantly higher at 16 to 19 months than at 3 or 9 months.We wish to thank Mrs. Susan Vanek and Miss Mary Ellen Wilsterman for technical assistance.