cssi/SciSciGPT-SciSciNet huggingface dataset:
Bayesian optimal interval designs for phase I clinical trials

Summary In phase I trials, effectively treating patients and minimizing the chance of exposing them to subtherapeutic and overly toxic doses are clinicians' top priority. Motived by this practical consideration, we propose Bayesian optimal interval (BOIN) designs to find the maximum tolerated dose and to minimize the probability of inappropriate dose assignments for patients. We show, both theoretically and numerically, that the BOIN design not only has superior finite and large sample properties but also can be easily implemented in a simple way similar to the traditional ‘3+3’ design. Compared with the well-known continual reassessment method, the BOIN design yields comparable average performance to select the maximum tolerated dose but has a substantially lower risk of assigning patients to subtherapeutic and overly toxic doses. We apply the BOIN design to two cancer clinical trials.
Implicit Theories of the Marital Institution

Building on existing theory and literature regarding implicit theories, I propose an application of implicit theories that focuses on assumptions about the potentially changeable nature of the institution of marriage. Implicit Theories of the Marital Institution (ITMI) distinguish beliefs about how fixed or malleable marriage is and can potentially be used in investigating how such beliefs are formed and interplay with other variables that influence premarital and marital behavior. Research and theoretical implications of ITMI are discussed.
A thermally induced avalanche failure mechanism in GaAs Gunn devices

High duty cycle and CW Gunn effect epitaxial devices are subject to premature failure due to avalanching induced by temperature gradients produced across the active layer. These temperature gradients are seen to effectively worsen existing doping gradients which initiate switching at a reduced bias level. Increases in average temperature are seen to vary the nominal breakdown field which in some cases has been seen to rise by a factor of two over the temperature range from 300 to 450°K.
Prevalence ofCampylobacter pylori and association with antral mucosal histology in subjects with and without upper gastrointestinal symptoms

To determine the incidence and significance of Campylobacter pyloriin patients undergoing routine endoscopic evaluation at this hospital, biopsies of the antrum were obtained from 132 patients and from 15 asymptomatic volunteers. Specimens were cultured and silver stained for the presence of C. pyloriand were examined histologically. C. pyloriwas detected in 67 (51%) patients and two (13%) volunteers (P=0.006).In patients, C. pyloriwas found significantly more often when the mucosa was inflamed (67%) than when the mucosa was normal (13%), and both volunteers with C. pylorihad chronic gastritis on histological examination. When compared to the volunteers, patients with upper gastrointestinal symptoms had a significantly increased prevalence of antral inflammation, even if the endoscopic examination was normal. C. pyloriis infrequently found in young asymptomatic adults but is found in both asymptomatic volunteers and patients in association with all forms of histological antral gastritis which is prevalent in patients with both normal endoscopic findings and peptic ulcer disease.
Heterosocial-skills training and covert sensitization: Effects on social skills and sexual arousal in sexual deviants.

Abstract There are few experimental investigations of the effects of social-skills training (SST) on sexual deviation. This study used a multiple baseline across 4 subjects with undesired sexual arousal to investigate the effects of heterosocial-skills training and covert sensitization on heterosocial skills and sexual-arousal patterns. SST produced large increases in heterosocial skills but it had unclear effects on sexual arousal. Subsequently, covert sensitization tended to reduce remaining deviant arousal but did not increase appropriate arousal significantly. These data generally support the view that individual components of sexual arousal require separate assessment and intervention.
Eidetecker: the professional communicator in the new visual culture

It is pointed out that, after Gutenberg's introduction of movable type an the printing press in the fifteenth century, and due to the influence of the Renaissance, Western culture entered a period of visual efflorescence. Then, due mainly to the influence of the Scientific Revolution, there occurred a derogation of visual experience in favour of word and abstract number. It is argued that, in the late twentieth century, technology, supported by developments in scientific theory, has given new efficacy to visual thinking and experience. Increasingly, illustrations of various types are employed to give meaning to otherwise incomprehensible data. Today's technical communicator must learn to deal effectively with the new demands of a visual culture, becoming not only a master of the new technology but also a possessor of a deep understanding of the theories and structures of visual knowledge. >
Charon phages: safer derivatives of bacteriophage lambda for DNA cloning

The Charon lambda bacteriophages have been developed as vectors for cloning. Their construction incorporates mutations that make them simple to use and also greatly increases their safety for the biological containment of cloned recombinant DNA. Three of the Charon vector phages, 3A, 4A, and 16A, have been certified for use as EK2 vector-host systems, when propagated in bulk in a special bacterial host, DP50SupF. We present here some of the data on which the safety of these systems was evaluated. DNA fragments ranging in size from 0 to 2.2 X 10(4) base pairs can be cloned in these EK2 Charon phages.
Modification of a seagrass community by benthic jellyfish blooms and nutrient enrichment

Anthropogenic activities are increasing the number and intensity of disturbances, often acting in concert, in ecosystems across the globe. One result of human activities in many marine ecosystems is an increased abundance of jellyfish (jellyfish blooms), which have garnered recent attention for their detrimental ecological and economic impacts. We conducted a field experiment to determine effects of proliferations of benthic jellyfish, Cassiopea spp., and another common disturbance, anthropogenic nutrient enrichment (via fertilizer additions), on a shallow seagrass community in Abaco, Bahamas. Results suggested a reduction in seagrass abundance and habitat complexity in both jellyfish and nutrient enrichment treatments. Jellyfish additions were associated with reduced faunal densities; nutrient enrichment drove shifts in faunal community composition. Grazing frequency was substantially higher in nutrient-enriched plots, and lower in plots with jellyfish alone or jellyfish combined with nutrients, suggesting that jellyfish may act as a deterrent to grazers. These findings highlight the inherent complexities in predicting ecological changes within shallow seagrass ecosystems.
Heavy metal chelators prolong motility and viability of sea urchin sperm by inhibiting spontaneous acrosome reactions

A variety of heavy metal chelating agents is known to prolong the fertilizing capacity and motility of sea urchin sperm. We report here that these agents maintain fertilizing capacity by preventing acrosome reactions which occur spontaneously after dilution of sperm into seawater. These chelating agents also inhibit acrosome reactions induced by high pH or egg jelly. Since induction of the acrosome reaction leads to steps that abolish motility, specifically a massive Ca2 + uptake and concomitant acidification of the cytoplasm, motility is prolonged by these chelators. These observations also suggest that heavy metals play a role in controlling the acrosome reaction in sea urchin sperm.
Integration and tolerance issues for resonant subwavelength gratings

A current micro-optical system project at Sandia National Laboratories employs an array of resonant subwavelength gratings (RSGs). An RSG functions as an extremely narrow wavelength and angular band reflector, or mode selector. Theoretical studies predict that the infinite, laterally-extended RSG can reflect 100% of the resonant light while transmitting the balance of the other wavelengths. Experimental realization of these remarkable predictions has been impacted primarily by fabrication challenges. Even so, we will present large area (1.0mm) RSG reflectivities as high as 100.2%, normalized to deposited gold. Broad use of the RSG will only truly occur in an accessible micro-optical system. The program at Sandia is a normal incidence array configuration of RSGs where each array element resonates with a distinct wavelength to act as a dense array of wavelength- and mode-selective reflectors. Because of the array configuration, RSGs can be matched to an array of pixels, detectors, or chemical/biological cells for integrated optical sensing. Micro-optical system considerations impact the ideal, large area RSG performance by requiring finite extent devices and robust materials for the appropriate wavelength. Experimental measurements are presented that demonstrate the component response as a function of decreasing RSG aperture dimension and off-normal input angular incidence.
Digital Flicker-Free Slow Scan Multispectral Imagery Display

A technique for displaying flicker-free real-time grey scale images from multiple spec-tral region slow scan imagers has been developed. Under control of an microprocessor, digital data from the imager is transferred one raster line per spectral region at a time via buffer memories into a bank of video graphic random access memories (VRAM). The VRAM bank generates standard video rate digital grey scale data continuously while being updated with the imager scan rate data. The digital VRAM data grey scales may be expanded under operator control for effective display of low level imagery. The microprocessor adds a calibration grey scale at the borders of the images for reference. Following conversion to analog, the imager video is combined with synchronizing signals to provide composite video. Titling and timing information is generated by an alphanumeric VRAM controlled by the microprocessor and inserted in the composite video. The VRAMs will automatically synchronize to an external video source, and an external mixer was used to combine the multi-spectral video with conventional visible camera video for video data suitable for display or recording.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Neurosteroids Reduce Social Isolation-Induced Behavioral Deficits: A Proposed Link with Neurosteroid-Mediated Upregulation of BDNF Expression

The pharmacological action of selective serotonin reuptake inhibitor antidepressants may include a normalization of the decreased brain levels of the brain-derived neurotrophic factor (BDNF) and of neurosteroids such as the progesterone metabolite allopregnanolone, which are decreased in patients with depression and posttraumatic stress disorders (PTSD). The allopregnanolone and BDNF level decrease in PTSD and depressed patients is associated with behavioral symptom severity. Antidepressant treatment upregulates both allopregnanolone levels and the expression of BDNF in a manner that significantly correlates with improved symptomatology, which suggests that neurosteroid biosynthesis and BDNF expression may be interrelated. Preclinical studies using the socially isolated mouse as an animal model of behavioral deficits, which resemble some of the symptoms observed in PTSD patients, have shown that fluoxetine and derivatives improve anxiety-like behavior, fear responses and aggressive behavior by elevating the corticolimbic levels of allopregnanolone and BDNF mRNA expression. These actions appeared to be independent and more selective than the action of these drugs on serotonin reuptake inhibition. Hence, this review addresses the hypothesis that in PTSD or depressed patients, brain allopregnanolone levels, and BDNF expression upregulation may be mechanisms at least partially involved in the beneficial actions of antidepressants or other selective brain steroidogenic stimulant molecules.
Evoked EEG gamma band response at slow rates of stimulation

We have sought to confirm the observations of an auditory gamma band response and study the effects associated with several stimulation parameters including ear of stimulation, stimulus intensity and frequency, and rate of repetition. The data confirm the presence of a burst of activity, within the gamma band, following auditory stimuli and suggest that the response is intimately, and specifically, related to fundamental auditory processes.
Two-Part Share Contracts, Risk, and the Life Cycle of Stars: Some Empirical Results from Motion Picture Contracts

What determines the market value of a star? This paper examines the size of fixed payments to leading actors in the U.S. motion picture industry from a sample of contracts between 1959 and 1989. Competing explanations for the size of compensation, including rent capture, risk sharing, signalling, and portfolio optimization by studio executives are explored. The size of fixed payment across all contract types moves with an actor's history of participating in top-20 grossing films over the past five, ten, fifteen, and twenty films. Further, the impact of past top-20 successes is enhanced by the length of the actor's career. When contracts are divided into those with both fixed payments and share payments and those with only fixed payments, the fixed payment in two-part share contracts is influenced to some extent by risk concerns, in addition to the actor's star power. Fixed-payment-only contracts are most strongly influenced by measures of signalling and star power. Data on both types of contract provide strong support for the rent-capture theory: actors are paid rents upfront for the star value they add to the production.
Advances and challenges in biosensor-based diagnosis of infectious diseases

Rapid diagnosis of infectious diseases and timely initiation of appropriate treatment are critical determinants that promote optimal clinical outcomes and general public health. Conventional in vitro diagnostics for infectious diseases are time-consuming and require centralized laboratories, experienced personnel and bulky equipment. Recent advances in biosensor technologies have potential to deliver point-of-care diagnostics that match or surpass conventional standards in regards to time, accuracy and cost. Broadly classified as either label-free or labeled, modern biosensors exploit micro- and nanofabrication technologies and diverse sensing strategies including optical, electrical and mechanical transducers. Despite clinical need, translation of biosensors from research laboratories to clinical applications has remained limited to a few notable examples, such as the glucose sensor. Challenges to be overcome include sample preparation, matrix effects and system integration. We review the advances of biosensors for infectious disease diagnostics and discuss the critical challenges that need to be overcome in order to implement integrated diagnostic biosensors in real world settings.
High Performance: The Culture and Technology of Drag Racing, 1950-1990

"Drag racing is an activity with a history so brief that people still around were there at the start", writes Post. "They can recall how it began as a hobby among young men infatuated with speed and power - "hot rodders", they were called. They have seen it become a compelling spectacle with a complex web of commercial relationships. And they have seen women impelled into mainstream roles to a degree far beyond what prevails in most similar activities".
Low current electrical stimulation upregulates cytokine expression in the anal sphincter.

Stem cells are an emerging treatment for regeneration of damaged anal sphincter tissues. Homing to the site of injury can be potentiated by stromal derived factor 1 (SDF-1) and monocyte chemotactic protein 3 (MCP-3) expression. The effects of electrical stimulation (ES) on upregulation of these cytokines were investigated. The anal sphincter complex of Sprague Dawley rats was stimulated with current of 0.25 mA, pulse duration of 40 pulses/s, pulse width of 100 μs, and frequency of 100 Hz for 1 or 4 h. Sham was created using the same needle which was inserted into the anal sphincter without electrical stimulation in different groups of animals. The rats were euthanized immediately or 24 h after stimulation. Cytokine analysis was performed using real-time polymerase chain reaction. Statistical analysis was performed. Results are presented as a fold increase compared to sham that was normalized to 1. SDF-1 and MCP-3 immediately after 1 h were 2.5 ± 0.77 and 3.1 ± 0.93 vs. sham, respectively, showing significant increase. After 1-h stimulation and euthanasia 24 h after, SDF-1 and MCP-3 were 1.49 ± 0.16 and 1.51 ± 0.14 vs. sham, respectively, showing significant increase. Immediately and 24 h after 4-h stimulation, SDF-1 was 1.21 ± 0.16 and 0.54 ± 0.16 vs. sham, respectively, and was not significantly different. Immediately and 24 h after 4-h stimulation, MCP-3 was 1.29 ± 0.41 and 0.35 ± 1.0 vs. sham, respectively, and was not significantly different. SDF-1 and MCP-3 after 1 h were significantly higher than after 4 h of stimulation at both time points. Electrical stimulation for 1 h significantly upregulates SDF-1 and MCP-3 expression that persists for 24 h. Prolonged stimulation reduced chemokine expression, suggesting electrolysis of cells.
The onset of convection in a multicomponent fluid layer

The onset of convective instability is investigated in a multicomponent fluid layer in which the density depends on N stratifying agencies with different diffusivities. The general equations required to determine the topology of the neutral curves and stability boundaries are given. We show that 1+2[(N−1)/2] (where [α] is the integer part of α) critical Rayleigh numbers are sometimes required to specify the linear stability criteria. This multivaluedness can be traced to the existence of disconnected neutral curves. The general theory is illustrated by a numerical example for the quintuply diffusive case (N=5).
Synthesis and single-crystal X-ray structure of [(DMPE)2Ru(C2H4)CH3]+[(3,5-(CF3)2C6H3)4B]−

Abstract The reaction of cis-(DMPE)2Ru(CH3)2 with [(3,5-(CF3)2C6H3)4B]−[H(OEt2)2]+ afforded the ruthenium cation [(DMPE)2RuCH3]+[(3,5-(CF3)2C6H3)4B]−. This cation underwent reaction with ethylene at room temperature to give the stable adduct trans-[(DMPE)2Ru(C2H4)CH3]+[(3,5-(CF3)2C6H3)4B]−, 1. The single crystal X-ray structure of 1 is reported.
On the effect of near-field excitations on the reliability-based performance and design of base-isolated structures

Abstract This work explores the effect of near-field excitations on the reliability-based performance and design of base-isolated systems. In particular base-isolated buildings under uncertain excitation are considered in this work. A probabilistic logic approach is adopted for considering the variability of future excitations. Isolation elements composed by rubber bearings are used in the present formulation. The non-linear behavior of the bearings is characterized by a biaxial hysteretic model which is calibrated with experimental data. The performance of the isolated system is defined in terms of the isolators deformations and the superstructure interstory drifts and absolute accelerations. First excursion probabilities are used as measures of system reliability. Two example problems involving large finite element building models are presented to illustrate the ideas set forth.
Effects of induced tolerance to bacterial lipopolysaccharide on myocardial infarct size in rats

Objectives: Induced tolerance to bacterial lipopolysaccharide (LPS) by pretreatment with sublethal doses of LPS has been shown to reduce the inflammatory response of monocytes, circulating PMNs and PMN adhesion to endothelial cells in response to subsequent stimuli, and also to increase cellular and organ tolerance to stress by other mechanisms. Therefore, we undertook to determine whether or not LPS desensitization is associated with reduced myocardial infarct size at 3 days after reperfusion following coronary occlusion. Methods: Rats were randomized to either daily intraperitoneal LPS injections to provide LPS tolerance, or to equal volumes of saline (controls). In both groups at day 7 nontransmural infarction was produced by a 45 min coronary occlusion followed by 3 days of reperfusion during which LPS injections were continued. Histologic infarct size was assessed as percent of the left ventricle and as a percent of the risk zone (determined by fluorescent microspheres). Results: Myocardial infarct size as percent of the left ventricle and of the risk zone were significantly reduced in the LPS-tolerant group ( n = 14) compared to control rats ( n = 12), the latter being reduced by 37% (33.6 ± 18.4 vs. 54.1 ± 8.6% of the risk zone, P < 0.002). The percentages of activated circulating PMN after LPS desensitization and saline pretreatment were not different prior to coronary occlusion (at 7 days), but 3 days after coronary occlusion and reperfusion the percent of activated PMNs in the treated group was markedly reduced compared to controls (2.9 ± 1.6 vs. 11.4± 7.2%, respectively, P < 0.02). Conclusions: LPS desensitization in rats for 1 week prior to coronary occlusion inhibited activation of circulating PMNs 3 days after reperfusion following 45 min of coronary occlusion. LPS also is well-known to induce heat stress proteins and may affect other protective mechanisms. These actions are associated with a significant reduction in myocardial infarct size in LPS-tolerant animals compared to untreated controls.
Metabolism of lipid peroxidation product, 4-hydroxynonenal (HNE) in rat erythrocytes: Role of aldose reductase

Abstract Lipid peroxidation represents a significant source of erythrocyte dysfunction and aging. Because the toxicity of lipid peroxidation appears to be in part due to aldehydic end products, we examined, in rat erythrocytes, the metabolism of 4-hydroxy-trans-2-nonenal (HNE), one of the most abundant and toxic lipid-derived aldehydes. Packed erythrocytes, 0.1 ml, completely metabolized 20 nmoles of HNE in 20 min. The glutathione conjugate of HNE and 4-hydroxynonanoic acid (HNA) represented 70 and 25% of the total metabolism, respectively. Approximately 70% of the metabolites were extruded to the medium. Upon electrospray ionization mass spectrometry, the glutathione conjugate resolved into two distinct species corresponding to glutathionyl HNE (GS-HNE) and glutathionyl 1,4-dihydroxynonene (GS-DHN). The concentration of GS-DHN formed was twice that of GS-HNE. Inhibition of aldose reductase by sorbinil and tolrestat led to a selective decrease in the formation of GS-DHN, although the extent of HNE glutathiolation was unaffected. Inhibitors of aldehyde or alcohol dehydrogenase, i.e., cyanamide and 4-methyl pyrazole, had no effect on the formation of HNA and GS-DHN, indicating that these enzymes are not significant participants in the erythrocyte HNE metabolism. Thus, oxidation to HNA, conjugation with glutathione, and further reduction of the conjugate by aldose reductase appear to be the major pathways of HNE metabolism in erythrocytes. These pathways may be critical determinants of erythrocyte toxicity due to lipid peroxidation–derived aldehydes.
Enhanced activation of a “nutrient-sensing” pathway with age contributes to insulin resistance

Calorie restriction improves life span whereas nutrient excess leads to obesity and unfavorable metabolic consequences, supporting the role for a cellular “nutrient sensor” in aging. Hexosamine biosynthetic pathway (HBP) is a candidate nutrient-sensing pathway. We hypothesized that altered nutrient sensing (by HBP) with age may provide a link among aging, nutrient flux, and insulin resistance. Using a hyperinsulinemic clamp in young rats, we show that experimental activation of HBP, through the systemic infusion of glucosamine, induced severe insulin resistance (36% decline in peripheral insulin action; P<0.05), increased adipose tissue gene expression of fat-derived peptides (PAI-1 by 4-fold, angiotensinogen 3-fold, leptin 2-fold, resistin 4-fold, and adiponectin 4-fold; P<0.01 compared with young saline-infused), and enhanced glycosylation of transcription factors, thus mimicking a physiological and biological phenotype of aging. We further demonstrate a greater activation of nutrient-sensing HBP with age in both old ad libitum-fed and calorie-restricted rats. Interestingly, old calorie-restricted animals rapidly develop insulin resistance when exposed to glucosamine, despite their “young” phenotype. These results suggest that altered nutrient sensing by HBP with age may be the link among nutrients, insulin resistance, and age-related diabetes.—Einstein, F. H., Fishman, S., Bauman, J., Thompson, R. F., Huffman, D. M., Atzmon, G., Barzilai, N., Muzumdar, R. H. Enhanced activation of a “nutrient-sensing” pathway with age contributes to insulin resistance.
The 5S ribosomal RNA gene clusters in Tetrahymena thermophila: strain differences, chromosomal localization, and loss during micronuclear ageing.

The organization of the 5S genes in the genome of Tetrahymena thermophila was examined in various strains, with germinal ageing, and the 5S gene clusters were mapped to the MIC chromosomes. When MIC or MAC DNA is cut with the restriction enzyme EcoRI, electrophoresed, blotted, and probed with a 5S rDNA probe, the banding patterns represent the clusters of the 5S rRNA genes as well as flanking regions. The use of long gels and 60 h of electrophoresis at 10 mA permitted resolution of some 30–35 5S gene clusters on fragments ranging in size from 30-2 kb (bottom of gel). The majority of the 5S gene clusters were found in both MIC and MAC genomes, a few being MIC limited and a few MAC limited. The relative copy number of 5S genes in each cluster was determined by integrating densitometric tracings made from autoradiograms. The total number of copies in the MAC was found to be 33% greater than in the MIC. When different inbred strains were examined, the majority of the 5S gene clusters were found to be conserved, with a few strain-specific clusters observed. Nine nullisomic strains missing both copies of one or more MIC chromosomes were used to map the 5S gene clusters. The clusters were distributed non-randomly to four of the five MIC chromosomes, with 17 of them localized to chromosome 1. A deletion map of chromosome 1 was constructed using various deletion strains. Some of these deletion strains included B strain clones which had been in continuous culture for 15 years. Losses of 5S gene clusters in these ageing MIC could be attributed to deletions of particular chromosomes. The chromosomal distribution of the 5S gene clusters in Tetrahymena is unlike that found for the well-studied eukaryotes, Drosophila and Xenopus.
X-ray Crystal Structures of [Et3NH][{(CO)5Mo(P(OCH2CMe2CH2O)O)}2H] and (CO)5Mo{μ-Ph2POPPh2}Mo(CO)5, Two Complexes Derived from the Hydrolysis of Coordinated Chloro-Phosphorous-Donor Ligands

X-ray crystal structures of [Et3NH][{(CO)5Mo(P(OCH2CMe2CH2O)O)}2H], 3, and (CO)5Mo{μ-Ph2POPPh2}Mo(CO)5, 2, are reported. Crystallization of 3 occurs in P-1 space group with a = 9.6944(19) A, b = 10.814(2) A, c = 19.730(4) A, α = 94.24(3)°, β = 92.23(3)°, γ = 113.47(3)°, Z = 4. Crystallization of 2 occurs in C2/c space group with a = 10.357(2) A, b = 20.149(4) A, c = 17.155(3) A, α = 90°, β = 97.28(3)°, γ = 90°, Z = 8. Compound 2 is a bimetallic complex with a P–O–P bridging group containing bond distances similar to that of other complexes in which two metal centers are bridged by a single R2POPR2 ligand. Compound 3 contains intermolecular hydrogen bonded P–O–H–O–P linkages with bond distances comparable to those seen in similar structures with intramolecular hydrogen bonding suggesting that the distance is a function of the nature of the bond and not affected by the cis arrangement of the ligands about the metal center. X-ray Crystal Structures of [Et 3 NH][{(CO) 5 Mo(P(OCH 2 CMe 2 CH 2 O) O)} 2 H] and (CO) 5 Mo{μ-Ph 2 POPPh 2 }Mo(CO) 5 , Two Complexes Derived from the Hydrolysis of Coordinated Chloro-Phosphorous-Donor Ligands Samuel B. Owens Jr., Abha A. Kaisare and Gary M. Gray X-ray crystal structures of [Et3NH][{(CO)5Mo(P(OCH2CMe2CH2O)O)}2H], 3, and (CO)5Mo{μ-Ph2POPPh2}Mo(CO)5, 2, have been determined.
Regeneration: Thomas Hunt Morgan's Window into Development

Early in his career Thomas Hunt Morgan was interested in embryology and dedicated his research to studying organisms that could regenerate. Widely regarded as a regeneration expert, Morgan was invited to deliver a series of lectures on the topic that he developed into a book, Regeneration (1901). In addition to presenting experimental work that he had conducted and supervised, Morgan also synthesized and critiqued a great deal of work by his peers and predecessors. This essay probes into the history of regeneration studies by looking in depth at Regeneration and evaluating Morgan’s contribution. Although famous for his work with fruit fly genetics, studying Regeneration illuminates Morgan’s earlier scientific approach which emphasized the importance of studying a diversity of organisms. Surveying a broad range of regenerative phenomena allowed Morgan to institute a standard scientific terminology that continues to inform regeneration studies today. Most importantly, Morgan argued that regeneration was a fundamental aspect of the growth process and therefore should be accounted for within developmental theory. Establishing important similarities between regeneration and development allowed Morgan to make the case that regeneration could act as a model of development. The nature of the relationship between embryogenesis and regeneration remains an active area of research.
Cell wall assembly of neurospora crassa isolation and analysis of cell wall less mutants

Cell-wall-less mutants ofNeurospora crassa were isolated by mutagenizing cells of the temperature-sensitive, protoplast-formingosmotic-1 mutant and screening for cultures that did not regenerate cell wall. Of the 24 strains isolated, 22 were found to have significantly reduced levels of (1–3)β-glucan synthase activity; none was found to be defective in chitin synthase activity. Genetic analysis by standard transmission genetics revealed that the glucan synthase defect was ascospore lethal. Complementation analysis by forced heterokaryosis revealed four complementation groups. In each case in which complementation of cell wall formation was observed, there was concomitant restoration of (1–3)β-glucan synthase activity. Our results indicate that glucan synthase activity is necessary, but not sufficient, for cell wall assembly and resulting morphogenesis.
The “It Gets Better Campaign”: An unfortunate use of queer futurity

The first “It Gets Better” video I saw was by Tim Gunn, star of the fashion reality TV show “Project Runway.”1 Part of a video project started by internationally syndicated sex and relationship col...
Effect of catalyst structure on the rate of alkane oxidation over platinum

Abstract The effect of catalyst structure on the intrinsic activity of platinum for methane and heptane oxidation has been determined. The reactions were carried out in 5% excess oxygen and at low conversion. Depending on the support and method of catalyst preparation, the platinum may be distributed between a dispersed and a crystalline phase. These phases show characteristic absorbance at 2067 and 2085 cm −1 , respectively, in the infrared spectrum of adsorbed carbon monoxide. These phases catalyze methane oxidation at different rates. The turnover frequency for methane oxidation at 608 K is between 0.001 and 0.01 s −1 for the dispersed platinum and between 0.05 and 0.10 s −1 for the crystalline platinum. The turnover frequency for heptane oxidation is insensitive to the platinum phase present, and varies from 0.003 to 0.011 s −1 at 413 K. For platinum dispersions ranging from 6 to 100%, the specific activities for methane and heptane oxidation are not significantly affected by crystallite size.
Study of the epitaxial–lateral-overgrowth (ELO) process for GaN on sapphire

Abstract Growth of GaN by MOVPE on mismatched substrates such as sapphire and SiC produces a columnar material consisting of many hexagonal grains ∼0.2–1.0 μm in diameter. However, the epitaxial–lateral-overgrowth (ELO) process for GaN creates a new material – single-crystal GaN. We have studied the ELO process using a MOVPE reactor featuring vertical gas flows and fast substrate rotation to synthesize GaN ELO samples. Characterization experiments consisted of plan-view scanning electron microscopy and vertical-cross-section transmission electron microscopy studies, which disclosed a large reduction in dislocations in the ELO regions of the GaN samples. Panchromatic and monochromatic cathodoluminescence images and spectra were employed to study the spatial variation of the optical properties of the GaN ELO samples.
Distortion of the Active Site of Chymotrypsin Complexed with a Serpin

There is no complete understanding of how serine protease inhibitors of the serpin family inhibit their target enzymes. Structural and biochemical studies have suggested that serpins utilize a mechanism that is distinct from the standard mechanism of inhibition proposed for most small protein protease inhibitors. Proton nuclear magnetic resonance spectroscopy was used in the present study to demonstrate a fundamental difference in the atomic environment of the catalytic triad of enzyme in complex with serpins when compared to uncomplexed enzyme and enzyme in complex with standard mechanism inhibitors. This work demonstrates that the active site of chymotrypsin is distorted when complexed to a serpin and makes tenable a mechanism of inhibition in which the serpin induces a conformational change in the enzyme that dramatically reduces or completely abrogates the catalytic activity of the protease.
The synthesis and photodimerization of 2h-2-benzazepine-1,3-diones

Abstract The photochemical dimerization of 2 H -2-benzazepine-1,3-diones has been described. The structures of the major products are assigned as the head-to-tail, 5, and the head-to-head. 7, photodimers on the basis of the analysis of the coupling constants in the NMR spectra. In addition, the structures of the minor products and attempts to convert 5 to 7 are discussed.
Islamic Work Ethic in a Dynamic World

Perceptions on of work and its relation to human life have occupied man for centuries and discussions about the concept of work among different traditions and cultures appear to be under influence of a certain ideology or particular religion. In this article, Professor Ali has analyzed the understanding of work ethics based on the Islamic perspective. However, as an introduction to this theme, he firstly elaborated the concept of work ethics in a historical context, drawing from Greek civilization up to our time. The idea of work ethics and its understanding among the key makers of Greco-Roman and later Judeo-Christian civilizations up to the industrial revolution and technological age of our times went through the profound changes. In contrast to the Islamic perspective of work ethics, the author claims that in the Western civilization the essential purpose of work despite all drastic comprehension of this notion remains of profitable nature. In Islam on the other hand, the question of work ethics is clo...
"Right tool," wrong "job": Manual vacuum aspiration, post-abortion care and transnational population politics in Senegal.

The “rightness” of a technology for completing a particular task is negotiated by medical professionals, patients, state institutions, manufacturing companies, and non-governmental organizations. This paper shows how certain technologies may challenge the meaning of the “job” they are designed to accomplish. Manual vacuum aspiration (MVA) is a syringe device for uterine evacuation that can be used to treat complications of incomplete abortion, known as post-abortion care (PAC), or to terminate pregnancy. I explore how negotiations over the rightness of MVA as well as PAC unfold at the intersection of national and global reproductive politics during the daily treatment of abortion complications at three hospitals in Senegal, where PAC is permitted but induced abortion is legally prohibited. Although state health authorities have championed MVA as the “preferred” PAC technology, the primary donor for PAC, the United States Agency for International Development, does not support the purchase of abortifacient technologies. I conducted an ethnography of Senegal's PAC program between 2010 and 2011. Data collection methods included interviews with 49 health professionals, observation of PAC treatment and review of abortion records at three hospitals, and a review of transnational literature on MVA and PAC. While MVA was the most frequently employed form of uterine evacuation in hospitals, concerns about off-label MVA practices contributed to the persistence of less effective methods such as dilation and curettage (D&C) and digital curettage. Anxieties about MVA's capacity to induce abortion have constrained its integration into routine obstetric care. This capacity also raises questions about what the “job,” PAC, represents in Senegalese hospitals. The prioritization of MVA's security over women's access to the preferred technology reinforces gendered inequalities in health care.
Analysis of 405-Mev Proton and 222-Mev Negative Pion Stars

An analysis is carried out of star formation in emulsion by 405-Mev protons and 222-Mev negative pions produced in the University of Chicago 450-Mev synchrocyclotron. A comparison of the proton stars with a Monte Carlo calculation is made. The results indicate that the cascade mechanism is important in these stars, but that present evaporation theories cannot completely explain the decay of the residual nucleus. Pion and proton stars of almost the same total excitation have quite different characteristics.
Introduction: The Search for Connections

Connections between the facts of people's personal circumstances and their judgments about social and political issues are often murky or invisible. This seems counterintuitive. The nature of social issues is such that most people in a particular society possess some information about them and, if pressed, will be able to offer an opinion concerning them; it would seem reasonable to assume that these opinions reflect the individual's personal circumstances in some way. Similarly, if a set of events is to qualify as a “social issue” it must affect people, even if indirectly; it is thus to be expected that social issues would influence the interpretation of and behavior in people's personal lives. Yet researchers who make these assumptions are frequently surprised. What is the nature of the associations between the events in one's private life and one's attitudes about sociopolitical matters? How often do the abstractions of larger issues remain isolated from the concrete realities of daily existence, and what circumstances bring the abstract and the concrete into alignment?
Estrogen prevents cholesteryl ester accumulation in macrophages induced by the HIV protease inhibitor ritonavir

Individuals with HIV can now live long lives with drug therapy that often includes protease inhibitors such as ritonavir. Many patients, however, develop negative long-term side effects such as premature atherosclerosis. We have previously demonstrated that ritonavir treatment increases atherosclerotic lesion formation in male mice to a greater extent than in female mice. Furthermore, peripheral blood monocytes isolated from ritonavir-treated females had less cholesteryl ester accumulation. In the present study, we have investigated the molecular mechanisms by which female hormones influence cholesterol metabolism in macrophages in response to the HIV protease inhibitor ritonavir. We have utilized the human monocyte cell line, THP-1 as a model to address this question. Briefly, cells were differentiated for 72 h with 100 nM PMA to obtain a macrophage-like phenotype in the presence or absence of 1 nM 17β-estradiol (E2), 100 nM progesterone or vehicle (0.01% ethanol). Cells were then treated with 30 ng/ml ritonavir or vehicle in the presence of aggregated LDL for 24 h. Cell extracts were harvested, and lipid or total RNA was isolated. E2 decreased the accumulation of cholesteryl esters in macrophages following ritonavir treatment. Ritonavir increased the expression of the scavenger receptor, CD36 mRNA, responsible for the uptake of LDL. Additionally, ritonavir treatment selectively increased the relative levels of PPARγ mRNA, a transcription factor responsible for the regulation of CD36 mRNA expression. Treatment with E2, however, failed to prevent these increases at the mRNA level. E2 did, however, significantly suppress CD36 protein levels as measured by fluorescent immunocytochemistry. This data suggests that E2 modifies the expression of CD36 at the level of protein expression in monocyte-derived macrophages resulting in reduced cholesteryl ester accumulation following ritonavir treatment. J. Cell. Biochem. 103: 1598–1606, 2008. © 2007 Wiley-Liss, Inc.
Caffeic acid phenethyl ester induces adrenoleukodystrophy (Abcd2) gene in human X-ALD fibroblasts and inhibits the proinflammatory response in Abcd1/2 silenced mouse primary astrocytes

X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder caused by mutations in the ABCD1 gene. Accumulation of very long chain fatty acids (VLCFA) that have been attributed to reduced peroxisomal VLCFA β-oxidation activity are the hallmark of the disease. Overexpression of ABCD2 gene, the closest homolog of ABCD1, has been shown to compensate for ABCD1, thus correcting the VLCFA derangement. The accumulation of VLCFA leads to a neuroinflammatory disease process associated with demyelination of the cerebral white matter. The present study underlines the importance of caffeic acid phenethyl ester (CAPE) in inducing the expression of ABCD2 (ALDRP), and normalizing the peroxisomal β-oxidation as well as the levels of saturated and monounsaturated VLCFAs in cultured human skin fibroblasts of X-ALD patients. The expression of ELOVL1, the single elongase catalyzing the synthesis of both saturated VLCFA (C26:0) and mono-unsaturated VLCFA (C26:1), was also reduced by CAPE treatment. Importantly, CAPE upregulated Abcd2 expression and peroxisomal β-oxidation and lowered the VLCFA levels in Abcd1-deficient U87 astrocytes and B12 oligodendrocytes. In addition, using Abcd1/Abcd2-silenced mouse primary astrocytes we examined the effects of CAPE in VLCFA-induced inflammatory response. CAPE treatment decreased the inflammatory response as the expression of inducible nitric oxide synthase, inflammatory cytokine, and activation of NF-κB in Abcd1/Abcd2-silenced mouse primary astrocytes was reduced. The observations indicate that CAPE corrects both the metabolic disease of VLCFA as well as secondary inflammatory disease; therefore, it may be a potential drug candidate to be tested for X-ALD therapy in humans.
Gravitationally bound quantum states of ultracold neutrons and their applications

We will review the discovery and characterization of gravitationally bound quantum states of neutrons. The lowest neutron quantum states in a gravitational potential were distinguished and characterized by a measurement of their spatial extent. The neutron transmission was observed through a slit with an absorbing top surface at a variable height. Second, a position-sensitive detector was used for a direct visualization of the wavefunction. An application is the search for new short-range interactions, which would alter the waveform of the quantum states.
Creating Control Systems: Edwin F. Gay and the Central Bureau of Planning and Statistics, 1917–1919

In tracing the work of Edwin Gay in the mobilization effort during the First World War, this article presents an intriguing picture of the wartime administration's gradual realization of its need for more accurate information for central economic and political decision making. Although Gay's specific agency was short-lived, the work he did, and the viewpoint he represented, contributed significantly to the search for coherent administration in the executive branch.
Miniature electron-optical columns

Miniaturized electron-optical systems based on a field emission microsource and a microlens for probe forming have been studied. The performance of systems with dimensions (length and diameter) in the submillimeter to millimeter range can exceed that of a conventional system over a wide range of potentials (100 V to 10 kV) and working distances (up to 10 mm). Electron-optical studies show that not only can a significant reduction in size be achieved but the performance in terms of resolution and especially beam current can also be greatly improved. A key component of the miniaturized system is the field emission microsource which provides an improvement of two to three orders of magnitude in effective brightness over the conventional field emission source. Among the options, the STM aligned field emission (SAFE) microsource appears most promising and a selective scaling approach has been developed to allow this source to operate over a wide range of potentials. Preliminary experimental studies of the microsource have been conducted. >
The New Gates in Harvard Yard: A Students' Response to the Philanthropist's Call to Action

Mr. Gates, the seniors gathered at Tercentenary Theatre were certainly well-accustomed to excellence and success. But in believing that “reducing inequity is the highest human achievement” Mr. Gates likely found himself with scarce company amid a class that had been cultivated in a collegiate environment oriented toward the achievement of financial success and prestige. Though Mr. Gates is correct in noting that among our peers, recognition of global inequities far exceeds that of previous generations, such knowledge levels have not yet transcended a vague awareness of global disparities in wealth and human rights. It certainly has not yet produced a general consensus that fighting inequity is the greatest form of human achievement. Nor has it compelled undergraduates to believe that, both in their current roles as students and in their lives beyond, they should care more about inequity given how well placed they are to chip away global disparities. Above Dexter Gate, through which students pass on a daily basis en route to their classes within Harvard Yard lies the inscription “Enter to grow in wisdom.” Upon exiting the Yard, students are in turn called to utilize this newly acquired wisdom in “depart[ing] to serve better thy country and thy kind.” Though university mission statements generally call for knowledge generation and the inculcation of social responsibility among student constituents, Gates’ speech highlights the continuing poor performance of elite universities in what Gates deems the most important measure of a modern public institution: impact on social inequity. Despite Gates’ hopeful remarks that we have attained an increased awareness of current social inequities, our experience has strongly suggested that Harvard as well as its peer universities have largely failed to challenge their students to grow in their understanding of and desire to ameliorate the causal roots of poverty and inequality. Knowledge about inequity represents a critical first step in improving ourselves and our institution against Gates’ criteria for two reasons. First, an under-
CURRENT APPROACHES TO IMAGING OF THE SELLAR REGION AND PITUITARY

Recent advances in MR imaging have enabled the radiologist to view the pituitary gland in its normal and diseased states to a greater extent than ever before. The techniques for obtaining quality images of the sellar region and the normal appearance of the pituitary gland are discussed. This article also discusses the imaging of several pituitary disease processes, with emphasis on pitutiary adenomas and recent advances in diagnosis and follow-up. Current controversies also are addressed.