cssi/SciSciGPT-SciSciNet huggingface dataset:
Development of a stacked, porous silk scaffold neuroblastoma model for investigating spatial differences in cell and drug responsiveness

Development of in vitro, preclinical cancer models that contain cell-driven microenvironments remains a challenge. Engineering of millimeter-scale, in vitro tumor models with spatially distinct regions that can be independently assessed to study tumor microenvironments has been limited. Here, we report the use of porous silk scaffolds to generate a high cell density neuroblastoma (NB) model that can spatially recapitulate changes resulting from cell and diffusion driven changes. Using COMSOL modeling, a scaffold holder design that facilitates stacking of thin, 200 μm silk scaffolds into a thick, bulk millimeter-scale tumor model (2, 4, 6, and 8 stacked scaffolds) and supports cell-driven oxygen gradients was developed. Cell-driven oxygen gradients were confirmed through pimonidazole staining. Post-culture, the stacked scaffolds were separated for analysis on a layer-by-layer basis. The analysis of each scaffold layer demonstrated decreasing DNA and increasing expression of hypoxia related genes (VEGF, CAIX, and GLUT1) from the exterior scaffolds to the interior scaffolds. Furthermore, the expression of hypoxia related genes at the interior of the stacks was comparable to that of a single scaffold cultured under 1% O2 and at the exterior of the stacks was comparable to that of a single scaffold cultured under 21% O2. The four-stack scaffold model underwent further evaluation to determine if a hypoxia activated drug, tirapazamine, induced reduced cell viability within the internal stacks (region of reduced oxygen) as compared with the external stacks. Decreased DNA content was observed in the internal stacks as compared to the external stacks when treated with tirapazamine, which suggests the internal scaffold stacks had higher levels of hypoxia than the external scaffolds. This stacked silk scaffold system presents a method for creating a single culture model capable of generating controllable cell-driven microenvironments through different stacks that can be individually assessed and used for drug screening.
The moral responsibilities of fandom

Using American football as a point of entry, I approach harmful sports from the perspective of fans’ roles and responsibilities. Given that sports’ profitability is a significant obstacle to reform...
Increasing Use of Ambulatory Video Visits for Pediatric Patients by Using Quality Improvement Methods

Introduction Live video visits for ambulatory encounters offer potential benefits, including access to remote subspecialty services, care coordination between providers, and improved convenience for patients. We aimed to increase the utilization of video visits for pediatric patients at our medical center using an iterative quality improvement process. Methods A multispecialty improvement team identified opportunities to increase video visit utilization and prioritized interventions using benefit-effort analyses. Interventions focused on 6 key drivers. The outcome measure was the percentage of ambulatory encounters conducted by video. The process measure was the percentage of ambulatory pediatricians conducting video visits. The balancing measure was the percentage of no-shows among scheduled video visits. All measures were analyzed using statistical process control. Results Interventions were associated with increases in our outcome and process measures from 0.1% to 1.2% and 0.6% to 6.3%, respectively, during the first 8 months. Subsequently, the novel coronavirus (COVID-19) pandemic was associated with further increases in these measures to 41.8% and 73.5%, respectively, over 3 months. The balancing measure increased from 0% at baseline to 14.7% with no special cause variation during the intervention period. The most impactful interventions included clinician training outreach, providing equipment, and streamlining MyChart patient enrollment. Conclusions This improvement project effectively increased pediatric ambulatory video visit utilization, although the most significant driver of utilization was the COVID-19 pandemic. Project interventions implemented before COVID-19 facilitated rapid video visit adoption during the pandemic. A similar improvement process may be beneficial for other medical centers aiming to improve video visit utilization.
Use of the PROMIS-10 global health in patients with chronic low back pain in outpatient physical therapy: a retrospective cohort study

Although evidence-based guidelines for physical therapy for patients with chronic low back pain (cLBP) are available, selecting patient-reported outcome measures to capture complexity of health status and quality of life remains a challenge. PROMIS-10 Global Health (GH) may be used to screen for impactful health risks and enable patient-centered care. The purpose of this study was to investigate the interrelationships between PROMIS-10 GH scores and patient demographics, health status, and healthcare utilization in patients with cLBP who received physical therapy. A retrospective review of de-identified electronic health records of patients with cLBP was performed. Data were collected for 328 patients seen from 2017 to 2020 in three physical therapy clinics. Patients were grouped into HIGH and LOW initial assessment scores on the PROMIS-10 Global Physical Health (PH) and Global Mental Health (MH) measures. Outcomes of interest were patient demographics, health status, and healthcare utilization. Mann–Whitney U and chi-square tests were used to determine differences between groups, and binary logistic regression was used to calculate odds ratios (OR) to determine predictors of PH-LOW and MH-LOW group assignments. The PH-LOW and MH-LOW groups contained larger proportions of patients who were African American, non-Hispanic, and non-commercially insured compared to PH-HIGH and MH-HIGH groups (p < .05). The PH-LOW and MH-LOW groups also had a higher Charlson comorbidity index (CCI), higher rates of diabetes and depression, and more appointment cancellations or no-shows (p < .05). African American race (OR 2.54), other race (2.01), having Medi-Cal insurance (OR 3.37), and higher CCI scores (OR 1.55) increased the likelihood of being in the PH-LOW group. African American race (OR 3.54), having Medi-Cal insurance (OR 2.19), depression (OR 3.15), kidney disease (OR 2.66), and chronic obstructive pulmonary disease (OR 1.92) all increased the likeihood of being in the MH-LOW group. Our study identified groups of patients with cLBP who are more likely to have lower PH and MH scores. PROMIS-10 GH provides an opportunity to capture and identify quality of life and global health risks in patients with cLBP. Using PROMIS-10 in physical therapy practice could help identify psychosocial factors and quality of life in the population with cLBP.
A Laurentian cratonic reference from the distal Proterozoic basement of Western Newfoundland using tandem in situ and isotope dilution U-pb zircon and titanite geochronology

The Humber Margin of Newfoundland preserves the most distal exposures of Proterozoic basement in northeastern Laurentia. Age uncertainty has permitted a range of hypotheses for its origin and links to subsequent tectonic events. One hypothesis has proposed large-scale orogen-parallel displacement between basement blocks in western Newfoundland. The apparent absence of Grenville- (∼1250–950 Ma sensu lato) or Taconic-aged (∼480–450 Ma) magmatism or metamorphism on the Corner Brook Lake Block (CBLB), which are defining features of the Humber Margin, has been reconciled by restoring the CBLB to a pre-Taconic position in Labrador with >400 km of post-Taconic dextral motion along the Humber River Fault. To test this model and better define the basement and Paleozoic rifted margin of North America, we conducted a geochronological study of the CBLB and the basement of the adjacent Humber Margin at Indian Head Range using tandem in situ and isotope dilution U-Pb zircon and titanite geochronology. These basement blocks, separated by the Humber River Fault, consist of ∼1500 and ∼1250 Ma protoliths, 1140 to 1135 Ma magmatism, 1000 to 970 Ma metamorphism, and ∼607 Ma intraplate magmatism. These basement blocks are also overlain by similar late Ediacaran to Cambrian siliciclastic successions with similar detrital zircon age spectra. From this set of geological data, we conclude that the Humber River Fault did not accommodate significant orogen-parallel displacement. New basement ages and a revised compilation of detrital zircon ages from overlying rift-related deposits contribute to a geochronologic cratonic reference datum for western Newfoundland9s crystalline basement, whose protolith has a restricted age range from circa 1500 to 950 Ma. New age constraints for metasedimentary rocks are also used to document a 1250 to 1135 Ma succession at Indian Head Range and a ∼1000 Ma succession on the CBLB associated with Grenvillian orogenesis. Protracted late Grenvillian tectono-thermal events are inferred from cores and metamorphic overgrowths of ∼990 to 920 Ma detrital titanite in late Ediacaran conglomerate overlying CBLB basement.
Frequency response model of the cat's medial gastrocnemius muscle acting through the ankle joint

The effect of the cat ankle joint passive viscoelastic properties on the dynamic response of the Medial Gastrocnemius (MG) was examined under isometric and load-moving conditions. Frequency response models were constructed of the muscle-joint system during sinusoidal isometric force oscillations and constant-mass lifting movements. These responses were compared against those obtained under the same loading condition after separating the muscle from its distal joint insertion. It was found that in isometric conditions, the muscle could be modeled as a critically damped second order system with a pure time delay, with the joint adding a pole-zero combination which reduced the system bandwidth. In load-moving conditions, two sets of double poles, two zeroes and a pure time delay were used to model the muscle, with the joint adding a pole-zero combination affecting the phase with no significant influence in the gain. It was concluded that the joint introduces dynamic effects to the muscle's response, which vary depending on the type of loading experienced by the joint. >
Constraint-Based Motion Planning Using Voronoi Diagrams

We present a novel algorithm for planning the motion of rigid and articulated robots in complex, dynamic, 3D environments. Our approach is to reformulate the motion planning problem as a simulation of a constrained dynamical system, and guide this system using generalized Voronoi diagrams (GVDs). In our framework, each rigid robot is subject to virtual forces induced by geometric and mechanical constraints. These may include constraints to have a robot follow an estimated path computed using a GVD, constraints to link rigid objects together to represent an articulated robot, or constraints to enforce a spatial relationship between multiple collaborative robots. The resulting algorithm uses all constraint forces to move the robot along an estimated path through the environment, while avoiding collisions with obstacles and enforcing joint and positional constraints. Our algorithm works well in dynamic environments with moving obstacles and is applicable to planning scenarios where multiple robots must move simultaneously to achieve a collision free path.
Mapping Yamunaji's scholarly tributaries: Childhood education and professional writing

This paper recognizes and celebrates Dr. Yamuna Kachru's multiple research contributions. Continuing with the metaphor of the powerful River Yamuna that the preceding paper uses, this one explores two tributaries or, more specifically, two applications of her research, namely, the value of her contributions to the field of childhood education and to professional communication. Implications and directions for future research are also outlined.
Torque Ripple Optimization of Switched Reluctance Motor Using Two-phase Model and Optimization Search Techniques

Torque ripple optimization scheme for SRM drive, based on fibonacci and exhaustive search method and 2-phase excitation model of SRM has been presented in this paper. The 2-phase excitation model of SRM used here takes into account the nonlinear effects because of saturation and mutual flux linkages caused by multi-phase excitation. In the proposed scheme the incoming and outgoing phase currents are modulated to minimize the torque ripple. Because of the highly nonlinear nature of torque, fibonacci and exhaustive search methods are used for optimizing the torque ripple, by simulating the model multiple times. Modulation of phase current is done by addition, subtraction and multiplication of constants and variables. This can be very easily achieved in DSP micro-controllers and FPGAs. Simulation and hardware results are presented for proposed optimization scheme and compared with constant current operation. It has been shown by simulations, that the proposed optimization scheme reduces the torque ripple by more than 50% as compared to traditional constant current scheme. The proposed optimization scheme has been experimentally validated. The experimental results show that the torque ripple is reduced by 49% to 45% for a reference current of 8A and 10A as compared to the constant current case.
The Enzymic Synthesis of Chorismic and Prephenic Acids from 3-Enolpyruvylshikimic Acid 5-Phosphate

The conversion of 3-enolpyruvylshikimate 5-phosphate (I) to phenylpyruvate was studied in extracts of Escherichia coli. A separation and partial purification was achieved of the two enzymic activities concerned: chorismate synthetase which catalyzed the 1,4-conjugate elimination (E2') of orthophosphate from I to yield chorismic acid (II), and the enzyme complex catalyzing the reactions chorismate → prephenate (III) → phenylpyruvate. Chorismate synthetase was inactive under aerobic conditions, and could be activated most effectively by a reduced flavin adenine dinucleotide-regenerating system in an atmosphere of H2 or N2. This was accomplished by the reduction of FAD with (a) reduced nicotinamide adenine dinucleotide and mammalian diaphorase or bacterial NADH dehydrogenase, or (b) platinum and H2. Reduced riboflavin, FMNH2, and platinum plus H2 alone could replace FADH2. Dithionite activated the enzyme with a short lag period. Sulfhydryl compounds were needed for maximal effect in these activation procedures, but were not indispensable. Chorismate synthetase was activated slowly by NADH, or by thorough removal of oxygen, but only in the presence of thiols. The activation by NADH was probably due to trace amounts of flavins, since their removal abolished this effect. Preliminary evidence suggested that Fe++ may be the labile component of the enzyme responsible for the sensitivity to oxygen, although added Fe++ was also inhibitory.
Reversion of Somatic Mutations of the Respiratory Syncytial Virus–Specific Human Monoclonal Antibody Fab19 Reveal a Direct Relationship between Association Rate and Neutralizing Potency

The role of affinity in determining neutralizing potency of mAbs directed against viruses is not well understood. We investigated the kinetic, structural, and functional advantage conferred by individual naturally occurring somatic mutations in the Ab H chain V region of Fab19, a well-described neutralizing human mAb directed to respiratory syncytial virus. Comparison of the affinity-matured Ab Fab19 with recombinant Fab19 Abs that were variants containing reverted amino acids from the inferred unmutated ancestor sequence revealed the molecular basis for affinity maturation of this Ab. Enhanced binding was achieved through mutations in the third H chain CDR (HCDR3) that conferred a markedly faster on-rate and a desirable increase in antiviral neutralizing activity. In contrast, most somatic mutations in the HCDR1 and HCDR2 regions did not significantly enhance Ag binding or antiviral activity. We observed a direct relationship between the measured association rate ( K on ) for F protein and antiviral activity. Modeling studies of the structure of the Ag–Ab complex suggested the HCDR3 loop interacts with the antigenic site A surface loop of the respiratory syncytial virus F protein, previously shown to contain the epitope for this Ab by experimentation. These studies define a direct relationship of affinity and neutralizing activity for a viral glycoprotein–specific human mAb.
Amino acid substitutions in the -35 recognition motif of sigma 70 that result in defects in phage lambda repressor-stimulated transcription.

Abstract The phage lambda repressor activates transcription of its own gene from the promoter PRM. Previous work has suggested that this activation involves a protein-protein interaction between DNA-bound repressor and RNA polymerase. To identify the subunit of RNA polymerase that participates in this putative interaction, we searched for polymerase mutants that responded poorly to repressor. We report here the isolation of three sigma mutants that caused defects in repressor-stimulated, but not basal, transcription from PRM. These mutants bear amino acid substitutions in a putative helix-turn-helix motif that sigma uses to recognize the promoter -35 region. We suggest that lambda repressor interacts directly with this helix-turn-helix motif in facilitating the formation of a productive initiating complex.
The disulfide bond in carboxypeptidase A: A

Abstract Carboxypeptidase A was assayed for active sulfhydryl groups by titration with HgCl 2 . A chloride ion probe NMR technique was utilized to observe the behavior of the mercuric ion. Although mercuric ion was found to bind to the enzyme, it could be removed by dialysis showing that the binding cannot be through a sulfur atom. The absence of sulfhydryl groups indicates that the two half cystine residues in the molecule must be linked by a disulfide bond.
Twenty-five years of progress, problems, and conflicting evidence in econometric forecasting. What about the next 25 years?

Abstract In the early 1940s, the Cowles Commission for Research (later, the Cowles Foundation) fostered the development of statistical methodology for application in economics and paved the way for large-scale econometric models to be used for both structural estimation and forecasting. This approach stood for decades. Vector autoregression (VAR), appearing in the 1980s, was a clear improvement over early Cowles Foundation models, primarily because it paid attention to dynamic structure. As a way of imposing long-run equilibrium restrictions on sets of variables, cointegration and error-correction modeling (ECM) gained popularity in the 1980s and 1990s, though ECMs have so far failed to deliver on their early promise. ARCH and GARCH modeling have been used with great success in specialized financial areas to model dynamic heteroscedasticity, though in mainstream econometrics, evidence of their value is limited and conflicting. Concerning misspecification tests, any model will inevitably fail some of them for the simple reason that there are many possible tests. Which failures matter? The root of the difficulty regarding all issues related to modeling is that we can never know the true data generating process. In the next 25 years, what new avenues will open up? With ever greater computational capacity, more complex models with larger data sets seem the way to the future. Will they require the automatic model selection methods that have recently been introduced? Preliminary evidence suggests that these methods can do well. The quality of aggregate data is no better than it was. Will greater use of more disaggregated data be sufficient to provide better forecasts? That remains an open question.
Patterns and trends in larval‐stage growth and mortality of teleost fish*

Weight-specific growth (G) and instantaneous mortality (M) rates are linked processes during early life, and the MIG ratio determines stage-specific mortality. A comparative analysis of five species identified patterns and trends in larval M and G, and their relationship to variability in larval cohort abundance. M declined with respect to body size in all species, although levels of M were variable between taxa and years. Rates of decline in M with respect to size generally were higher than predicted by size-spectrum theory. G varied between species and years, but was less variable than M. In some species (e.g. striped bass and American shad) G increased appreciably before declining, while in others G declined throughout the larval stage. Consequently, stage-specific mortality, which is governed by MIG and body size, declined slowly or was relatively constant throughout the larval stage. Cohort biomass declined during the early larval stages. and began to increase only when larvae attained the ‘transition size’ at which MIG < 1.0. Annual variability in transition sizes and ages, which is a consequence of trends, patterns, and variability in MIG, can act to control recruitment. Mortality is growth-dependent and growth-related factors are correlated with recruitment potentials, but measures of larval growth alone are not sufficient to predict or explain variability in recruitments.
Physical and Biological Variables Useful for Predicting Population Characteristics of Smallmouth Bass and Rock Bass in an Ozark Stream

Abstract Population characteristics of smallmouth bass (Micropterus dolomieui) and rock bass (Ambloplites rupestris) in Jacks Fork River, Missouri, were predicted from habitat and biological variables. We measured 32 variables at 20 sites that we believed might affect fish populations, and used multiple regression analysis to investigate relations between these variables and biomass, density, relative weight (Wr, an index of fish condition), and proportional stock density (PSD, an index of population size structure). Variability in density and biomass of both species was best associated with amounts of large substrate (boulders and cobble), undercut banks, and aquatic vegetation. Variability in Wr for both species was best explained by water temperature and the density of crayfish. Equations for both species were applied with satisfactory accuracy and precision to an independent data set. Variability in PSD was best explained by the presence of woody structure, aquatic vegetation, and large boulders; howe...
Relationship between Rhythmic Motor Activity and Plasma Luteinizing Hormone in Ovariectomized Sheep

The timing of the episodic secretion of luteinizing hormone (LH) in ovariectomized ewes was investigated with respect to an ultradian rest-activity cycle. Individual sheep were enclosed in a chamber w
New stains for blood and bone marrow cells.

Traditionally, blood and bone marrow cells have been identified based on their characteristic shapes and colors when stained with one of several panoptic stains including Wright's or Giemsa's. As questions arose regarding the origin of normal and leukemic cells, cytochemical stains were developed. These stains help identify cells on the basis of a distinctive metabolite or enzyme. As part of an ongoing tradition in which textile dyes are used for biological staining, several new stains have been applied to hematologic staining. These include C.I. basic blue 41, basic blue 141, basic blue 93, and an assymetrical polymethine dye. As additional cell-selective stains are developed, we can anticipate further improvements in our ability to identify normal and malignant hematopoietic cells.
Distribution of individual fatty acids in the crystallization fractions of lard

Distribution of the individual fatty acids in the triglycerides of lard was determined by fractional crystallization, partial enzymatic hydrolysis with steapsin, and fatty acid analyses by GLC. It was found that none of the individual fatty acids corresponded to a random distribution in the crystallization fractions, but that the distribution of the total saturated and total unsaturated acids was very nearly random. The short chain fatty acids, C14 and C16, both saturated and unsaturated, were found to be more predominant in the 2-position than in the 1- and 3-positions of the lard triglycerides. All of the C18 fatty acids were found to be more predominant in the 1- and 3-positions.
Organization of corticocortical connections in human visual cortex.

Abstract Clinical and psychophysical observations indicate that the visual cortex is critical for the perception of color, form, depth, and movement. Little, however, is known about the cortical circuitry that underlies these functions in humans. In an attempt to learn more about these connections, we have traced projections of primary (V1) and secondary (V2) visual cortex in the postmortem, fixed human brain, using the fluorescent dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate as an axonal marker. The results show that V1 makes a forward projection to layers 3 and 4 of V2, and V2 projects back to layers 1, 2, 3, 5, and 6 of V1. Some V2 injections also show an input to layer 4B of V1. Projections to 4B probably originate from cytochrome oxidase (CO)-reactive stripes that we have identified in V2. Differential connections between CO-rich (blobs) and CO-poor regions (interblobs) also exist within V1; blobs are connected to blobs and interblobs are connected to interblobs. The results show that the connections in human visual cortex are similar to those of nonhuman primates and that their organization is consistent with the concept of multiple processing streams in the visual system.
Wavelength multiplexed reflection matched spatial filters using LiNbO3

Abstract The wavelength multiplexing properties of a reflection filter are investigated. A photorefractive LiNbO3 crystal was used to construct an experimental filter. The wavelength selectivity and shift invariant properties of the filter were analyzed and experimentally verified.
An optimization approach for sustainable development planning of savanna systems

Abstract A savanna system is a natural ecosystem in which the competition between grass and woody vegetation in a semi-arid rangeland should be maintained for its sustainable development. Finding an optimal management plan for obtaining maximum economic profit from raising cattle without loss of sustainability of the savanna system during a planning period is a great challenge for rangeland managers. In this study, we formulate the sustainable development planning of the savanna system as an optimal control model, in which maximization of the stocking rate of cattle during the planning period is chosen as the objective while sustainable development requirements are achieved through the constraints represented by the desired final state of the system. Using Pontryagin's maximum principle, the model is transformed into a two-point boundary-value problem with nonlinear differential equations that is then solved using an iterative approach. An example with a specified desired final state in a savanna system without fire is used to demonstrate the performance of the model and the algorithm. Numerical experiments show that the planning strategy obtained from the optimal control model achieves maximum economic profit from raising cattle during the planning period and simultaneously improves the resilience of the system and maintains sustainable development of the rangeland. The outcomes demonstrate that resilience, sustainable development and economic profit are consistent concepts in optimal management strategy for rangeland management.
Short-wavelength laser studies at MIT: an update (Invited Paper)

We are exploring low Z Ni-like ions for use in a small-scale EUV laser experiment which is under development at MIT. In this paper, we discuss the basic motivation for our approach, the spectroscopy of the laser line positions, and basic physics models of the laser kinetics of the upper and lower laser states.
Moses Almosnino's epistles: a sixteenth-century genre of Sephardi vernacular literature

It is commonly believed that Ladino (Judeo-Spanish) literature emerged in the Ottoman Empire in the eighteenth century when the Sephardi vernacular became “independent” of Castilian. Without discussing the linguistic validity of the latter claim, I will show not only that Ottoman Sephardim already had a literature of their own in the sixteenth century, but that contacts with Peninsular culture and the needs of Iberian exiles brought a new literary subgenre into existence. The Sephardi immigration to the Ottoman lands lasted through the first decades of the eighteenth century, but it had significantly waned by the early seventeenth century. While the immigration continued, Ottoman Jews had access to some of the books published in Spain. Furthermore, the ex-conversos returning to Judaism produced a short-lived audience of educated Jews who were not fluent in Hebrew. While most sixteenth-century Ladino works were translations of religious Hebrew texts, Moses Almosnino chose to write original secular works fo...
Yeast Phosphofructokinase-1 Subunit Pfk2p Is Necessary for pH Homeostasis and Glucose-dependent Vacuolar ATPase Reassembly

V-ATPases are conserved ATP-driven proton pumps that acidify organelles. Yeast V-ATPase assembly and activity are glucose-dependent. Glucose depletion causes V-ATPase disassembly and its inactivation. Glucose readdition triggers reassembly and resumes proton transport and organelle acidification. We investigated the roles of the yeast phosphofructokinase-1 subunits Pfk1p and Pfk2p for V-ATPase function. The pfk1Δ and pfk2Δ mutants grew on glucose and assembled wild-type levels of V-ATPase pumps at the membrane. Both phosphofructokinase-1 subunits co-immunoprecipitated with V-ATPase in wild-type cells; upon deletion of one subunit, the other subunit retained binding to V-ATPase. The pfk2Δ cells exhibited a partial vma growth phenotype. In vitro ATP hydrolysis and proton transport were reduced by 35% in pfk2Δ membrane fractions; they were normal in pfk1Δ. In vivo, the pfk1Δ and pfk2Δ vacuoles were alkalinized and the cytosol acidified, suggestive of impaired V-ATPase proton transport. Overall the pH alterations were more dramatic in pfk2Δ than pfk1Δ at steady state and after readdition of glucose to glucose-deprived cells. Glucose-dependent reassembly was 50% reduced in pfk2Δ, and the vacuolar lumen was not acidified after reassembly. RAVE-assisted glucose-dependent reassembly and/or glucose signals were disturbed in pfk2Δ. Binding of disassembled V-ATPase (V1 domain) to its assembly factor RAVE (subunit Rav1p) was 5-fold enhanced, indicating that Pfk2p is necessary for V-ATPase regulation by glucose. Because Pfk1p and Pfk2p are necessary for V-ATPase proton transport at the vacuole in vivo, a role for glycolysis at regulating V-ATPase proton transport is discussed.
Effects of stimulus duration on perceptual latency in the fovea

Perceptual latency to a foveal stimulus was determined with the perceived-order method. In Experiment 1, luminance ranged from 29 to 114,000 td, stimulus durations ranged from 2 to 2,500 msec, and all stimuli were 100% detectable. One observer showed no significant duration effect, and the other showed a significant, but irregular, effect. In Experiment 2, absolute threshold was determined at the same durations, and perceptual latencies were subsequently determined with luminance.1 log above absolute threshold (100% detectable). Latencies increased at long durations for both observers. This result can probably best be explained in terms of probability summation.
Cryptosphaerolide, a cytotoxic Mcl-1 inhibitor from a marine-derived ascomycete related to the genus Cryptosphaeria

Examination of the saline fermentation products from the marine-derived ascomycete fungal strain CNL-523 (Cryptosphaeria sp.) resulted in the isolation of cryptosphaerolide (1). The new compound is an ester-substituted sesquiterpenoid related to the eremophilane class. The structure of the new compound was assigned by spectroscopic and chemical methods. Cryptosphaerolide was found to be an inhibitor of the protein Mcl-1, a cancer drug target involved in apoptosis. It also showed significant cytotoxicity against an HCT-116 human colon carcinoma cell line, indicating that the compound may be of value in exploring the Mcl-1 pathway as a target for cancer chemotherapy.
Use of Pulverised and Fluidised Combustion Coal Ash in Secondary Road Construction

The research presented herein was undertaken to examine the viability of pulverised coal combustion (PCC) fly ash and fluidised bed combustion (FBC) spent bed, as a primary cementitious material and a secondary fine aggregate, respectively, for production of mixtures suitable for low-volume county and other secondary roads. To achieve the stated objective, the mechanical properties of a number of previously identified optimum PCC/FBC composites were studied in the laboratory and field. The characteristics such as unconfined uniaxial compressive strength, splitting tensile strength, modulus of elasticity and Poisson's ratio, absorption, resistance to freezing and thawing, and length change were investigated. Results conclude that the engineering properties of the PCC/FBC composites exceed those of the conventional mixes used in secondary roads. The field results reaffirm that the engineering characteristics of the laboratory mixtures can be easily attained in field. The suggested thickness design requireme...
Reservoir of Bacterial Exotoxin Genes in the Environment

Many bacteria produce secreted virulence factors called exotoxins. Exotoxins are often encoded by mobile genetic elements, including bacteriophage (phage). Phage can transfer genetic information to the bacteria they infect. When a phage transfers virulence genes to an avirulent bacterium, the bacterium can acquire the ability to cause disease. It is important to understand the role played by the phage that carry these genes in the evolution of pathogens. This is the first report of an environmental reservoir of a bacterial exotoxin gene in an atypical host. Screening bacterial isolates from the environment via PCR identified an isolate with a DNA sequence >95% identical to the Staphylococcus aureus enterotoxin A gene (sea). 16S DNA sequence comparisons and growth studies identified the environmental isolate as a psychrophilic Pseudomonas spp. The results indicate that the sea gene is present in an alternative bacterial host, providing the first evidence for an environmental pool of exotoxin genes in bacteria.
Ultraviolet laser-induced fluorescence spectrum of fluorochlorocarbene in solid argon

Abstract CFCl has been produced for spectral investigation by matrix reactions of alkali metal atomic beams with CFCl 3 in argon followed by rapid quenching to 15°K on a tilted copper wedge. When these samples were irradiated with near uv light from a krypton ion laser, a very intense, highly structured fluorescence spectrum was observed. This emission system extended from about 25 000 cm −1 to 15 000 cm −1 and peaked in intensity at about 22 000 cm −1 . The three most intense progressions are assigned to transitions from a common excited state to ground state levels (0 v 2 0), (1 v 2 0) and (1 v 2 1). New molecular constants determined from these progressions include ω 2 0 = 446 cm −1 , x 22 = −1.2 cm −1 , x 12 = −3 cm −1 , x 23 = −4 cm −1 , and x 13 = −6 cm −1 . CFCl was also produced by in situ photolysis of CFCl 3 using laser plasma emission and by alkali metal atom reactions with CF 2 Cl 2 , CF 2 ClBr, and CHFCl 2 .
Discussion of Research Implications

Having grown up in Kansas during dust storms and an undisguised depression, I am perhaps not quite as horrified by Gray's list of horrors as some younger colleagues might be. Unsettled commodity prices do not seem as hopeless as prices that have firmly settled near zero. However, I do share his and others' deep concern and their hope that economists can make useful contributions to the resolution of current difficulties.
A Molecular Beacon Defines Bacterial Cell Asymmetry

Many cells divide asymmetrically by generating two different cell ends or poles prior to cell division, but the mechanisms by which cells distinguish one pole from the other is poorly understood. In this issue of Cell, Huitema et al. (2006) and Lam et al. (2006) describe a protein that defines one specific pole of a bacterial cell by localizing to the site of cell division to be inherited by both progeny at the resulting new poles.
Energetics and defect clustering trends for trivalent rare earth cations substituted in UO2

Abstract Trends in the energetics and defect clustering tendencies for UO 2 compounds substituted with trivalent rare earth cations (M 3+ ) are investigated computationally using methods based on density functional theory. Higher energetic stability of U 1− x M x O 2−0.5 x solid solutions relative to constituent oxides and increased preference for higher oxygen coordination around the trivalent cation are found with increasing size of the M 3+ species. The implications of the computational results for the effect of trivalent fission products on oxygen ion mobility in spent fuel are discussed.
Constructing the search for a job in academia from the perspectives of self-regulated learning strategies and social cognitive career theory

Abstract Four international doctoral graduates who found jobs in American academia wrote narratives about their job search process and were interviewed afterwards for this descriptive qualitative study. Retrospective narratives, responses to open-ended questions, and discussions in focus groups supported the integration of the self-regulated learning strategies into the social cognitive career theory to explain the learning aspect of the job search process. The strategies used by the participants during the job search process were identified with most categories of the self-regulated learning strategies in the literature, and the participants’ self-oriented cultural perspectives and how these cultural perspectives interacted with perceptions about the job search process in the academic world of work were examined. The findings of this study contribute to the social cognitive career theory by introducing the job candidates’ self-regulated learning procedure and could be resources for doctoral students who plan to make a successful transition from students to professors and/or researchers.
Metabolic cascades in marine microbial communities.

It is 3:00 AM and a thousand-pound rosette is swinging off the back of the ship. The rosette cradles dozens of Niskin bottles that contain water samples retrieved from various depths. As the crew laboriously secures all moving parts, you get soaked with 4 °C seawater setting up filters to capture the viruses and microbes in the water samples, the efforts hindered by the ship plowing through 25+-foot swells. Conical tubes roll around the bench and the microscope has been slammed so often that it is almost impossible to check that the filters are working. Two hours later the ship has arrived at the next station and the rosette is dropped back into the deep. This is your chance to catch some hours of sleep before doing it all over again. Only 3 weeks more to go. Drifting off in the bunk, you dream of sending undergraduate “volunteers” on the next research cruise.
On the Influence of a Lower Layer on the Propagation of Nonlinear Oceanic Eddies

Abstract The one-layer, reduced-gravity, also called equivalent-barotropic, model has been widely used in countless applications. Although its validity is based on the assumption that a second, lower layer is sufficiently deep to be dynamically inactive, the question of how deep that second layer ought to be has not yet received thorough examination. When one considers the importance of the two processes excluded from the reduced-gravity model, namely barotropic motion and baroclinic instability, the conventional choice of a second layer much deeper than the first might be too simplistic. A scaling analysis aimed at covering all two-layer regimes, geostrophic as well as ageostrophic, leads to a double criterion, requiring that the total depth of fluid be much larger than either of two values. These values, resulting from f-plane and β-plane dynamics, apply to the shorter and longer scales, respectively. A number of numerical experiments on the propagation of eddies on the β-plane with various eddy radii a...
SecA alone can Promote Protein Translocation and Ion-Channel Activity: SecYEG Increases Efficiency and Specificity

SecA is an essential component of Sec translocase through which unfolded preproteins cross bacterial cytoplasmic membranes. The current prevailing view depicts SecYEG as the essential core of the protein-conducting channel, while SecA is the peripheral subunit that functions as an ATPase to drive the peptide chain through the SecYEG channel. In a major deviation, we now find that SecA with liposomes alone can promote protein translocation, and can elicit ion-channel activity in the oocyte whole cell recordings and in patch clamp single channel recordings. We previously reported that SecA forms ring-like pore structures upon binding with anionic phospholipids, providing the biophysical basis of SecA-liposomes channel activities. Further studies show that SecA-liposomes are less efficient and lose signal peptide recognition specificity, resembling PrlA suppressor mutants. Addition of purified SecYEG in the SecA-liposomes system restores the efficiency and the signal peptide specificity in ion-channel activity and in translocation of proOmpA and ProPhoA. Our data indicate that there is a protein-conducting channel in which SecA plays an important structural role as the core of the channel. Using N-terminal SecA deletion truncated domains of 901 residues SecA and liposomes in the oocytes recordings, we identify two critical SecA domains for the formation of pore channel activity: with phospholipids alone, and for higher activity with SecYEG. The N-terminal region located on amino acid residues #668-828 is required for interaction with liposomes, and #640-649 for interaction with SecYEG, to form functional channels. In a domain reconstitution system, two fragments, N-SecA1-640 and C-SecA610-901 together interact with liposomes to promote channel activity in oocytes. Our findings establish that SecA forms channel with liposomes, and SecA domains can be identified for intramolecular interaction and with SecYEG for electrophysiological channel activity.
Hematopoietic progenitor cell mobilization is mediated through β-2 and β-3 receptors after injury

Hematopoietic suppression after shock and trauma has been observed both in animal models and humans.1–3 Prolonged bone marrow (BM) dysfunction after severe injury is part of the multiple organ failure seen after trauma, and it is manifest clinically as a persistent anemia despite normal or even elevated erythropoietin levels.4 In addition, the persistent anemia and multiple blood transfusions are believed to be major contributors of morbidity and mortality.5,6 The etiology of BM suppression after injury is multifactorial, and it is associated with impaired growth of hematopoietic progenitor cells (HPCs) and stromal cells within the BM, along with a mobilization of HPCs into the peripheral circulation.7 Shah et al.8 have shown that HPCs mobilize to peripheral blood (PB), sequester in injured tissue, and are likely involved in tissue repair. The trafficking of HPCs to and from the BM is a complex and highly regulated process that is not fully understood. The sympathetic nervous system, through its BM innervations, has been proposed as a crucial regulator of HPC mobilization.9,10 Granulocyte-colony stimulating factor (G-CSF) promotes HPC mobilization by suppressing the expression of adhesion molecules between the HPCs and the BM matrix.9 Katayama et al.9 found that HPC mobilization following G-CSF injection was significantly reduced following chemical sympathectomy with 6-hydroxydopamine. Despite the evidence supporting the role of the sympathetic nervous system in HPC trafficking, the exact mechanism involved and its role after trauma have not been shown. Major trauma induces a significant and sustained release of catecholamines, and the activation of β-adrenergic receptors by catecholamines has been shown to induce hypermetabolism, tachycardia, and increased myocardial oxygen demand.11–13 β-Adrenergic blocades (BBs) have beneficial cardiac, metabolic, and immunomodulatory effects.14–16 In addition, BB use has been associated with improved outcomes in both burn and trauma patients.14,17 One potential mechanism, which may account for the improved outcomes with BB in times of stress involves an inhibition of immunomodulation caused by catecholamines.18 Previous work in our laboratory has shown that norepinephrine impacts BM progenitor cell growth and mobilization in a dose-dependent manner and that nonselective BB with propranolol reduced HPC mobilization into the periphery and HPC growth in injured tissue.19,20 However, given the extensive physiologic and immunomodulatory effects of nonselective BB, the aim of this study is to delineate the role of specific β-adrenergic receptors in HPC growth and mobilization.
Martin Gibbs and the peaceful uses of nuclear radiation, 14 C

This abstract is a prologue to this paper. Prior to his health failing, Martin Gibbs began writing remembrances of his education and beginning a science career, particularly on the peaceful uses of nuclear radiation, at the U.S. Brookhaven National Laboratory (BNL), Camp Upton, NY. Two years before his death Martin provided one of us (Govindjee) a draft text narrating his science beginnings in anticipation of publication in Photosynthesis Research. Govindjee edited his draft and returned it to him. Later, when it became difficult for him to complete it, he phoned Govindjee and expressed the desire that Govindjee publish this story, provided he kept it close to his original. Certain parts of Martin’s narrations have appeared without references (Gibbs 1999). The Gibbs family made a similar request since the narrations contained numerous early personal accounts. Clanton Black recently presented an elegant tribute on Martin Gibbs and his entire science career (Black 2008). Clanton was given the draft, which he and Govindjee then agreed to finish. This chronicle is their effort to place Gibbs’s narrations about his education and his maturation scientifically, in context with the beginnings of biological chemistry work with carbon-14 at the BNL (see Gibbs 1999). Further, these events are placed in context with those times of newly discovered radioisotopes which became available as part of the intensive nuclear research of World War II (WW II). Carbon-14, discovered during WW II nuclear research in 1940, was extremely useful and quickly led to the rapid discovery of new carbon metabolism pathways and biochemical cycles, e.g., photosynthetic carbon assimilation, within a decade after WW II.