cssi/SciSciGPT-SciSciNet huggingface dataset:
Protein-protein and protein-DNA interactions of σ70 region 4 involved in transcription activation by λcI

The cI protein of bacteriophage lambda (lambdacI) activates transcription from promoter P(RM) through an acidic patch on the surface of its DNA-binding domain. Genetic evidence suggests that this acidic patch stimulates transcription from P(RM) through contact with the C-terminal domain (region 4) of the sigma(70) subunit of Escherichia coli RNA polymerase. Here, we identify two basic residues in region 4 of sigma(70) that are critical for lambdacI-mediated activation of transcription from P(RM). On the basis of structural modeling, we propose that one of these sigma(70) residues, K593, facilitates the interaction between lambdacI and region 4 of sigma(70) by inducing a bend in the DNA upstream of the -35 element, whereas the other, R588, interacts directly with a critical acidic residue within the activating patch of lambdacI. Residue R588 of sigma(70) has been shown to play an important role in promoter recognition; our findings suggest that the R588 side-chain has a dual function at P(RM), facilitating the interaction of region 4 with the promoter -35 element and participating directly in the protein-protein interaction with lambdacI.
Why mach bands are not seen at the edges of a step

Abstract Mach bands are seen at the two ends of a ramp in luminance from one uniform level to another. Narrow, sharp-edged stimuli centered on the ramp attenuate both Mach bands simultaneously. Conclusion: Mach bands are not seen at the edges of an abrupt step change in luminance because the sharp edges actively suppress them.
Temperature fluctuations in pulverized coal (P.C.) flames

Abstract Fluctuating temperatures in pulverized coal (p.c.) flames were found to have both random and periodic behavior. There was a broad-band (white-noise) frequency variation, with all frequencies lying below 100 Hz, and a strong periodic frequency at about 2 Hz, identified as due to pulsations from the feeder-screw. Outside the (essentially trivial) 2-Hz periodic fluctuation, the variations in the temperatures at a particular location were random with time, with standard deviations of the individual measurements of 30–50 degrees, and for the mean, of less than 5 degrees. The variations also showed a strong inverse correlation with the radiating particle area. These conclusions are based on a data tabulation of nearly 3600 temperature measurements. Measurements were made with a two-color pyrometer at 800 and 1000 nm (25 nm bandwidth); they were made across a square-section combustion tunnel with a maximum path length of 165 mm. This path length was varied by setting the pyrometer sensor head (a water-cooled quartz rod) flush with one wall and inserting a water-cooled target to different depths from the other wall or alternatively by moving the sensor head towards the fixed target. The signal amplitude was linearly proportional to the path length, showing that there was no measurable self-absorption across the tunnel. The temperatures across the flame were constant within the error limits. The random, broad-band temperature fluctuations are attributed to random fluctuations in particle size distribution, with the recorded temperature being an area-weighted mean. An increase of fine particles will increase the radiating area but will bias the weighted temperature towards the smaller particles, which are burning at lower temperatures. This accounts qualitatively for the inverse correlation between temperature and radiation area obtained experimentally. This is regarded as the most important result obtained.
3-D measurements of separated flow over rigid plates with spanwise periodic cambering at low Reynolds number

Abstract Measurements of the flow field around a flat plate and rigid plates with spanwise periodic cambering were performed using volumetric three-component velocimetry (V3V) at a Reynolds numbers of 28,000 at α =12° where the flow is fully separated. The Reynolds normal and shear stresses, and the streamwise, spanwise and normal components of the vorticity vector are investigated for three-dimensionality. Flow features are discussed in context of the periodic cambering and corresponding aerodynamic force measurements. The periodic cambering results in spanwise variation in the reversed-flow region, Reynolds stresses and spanwise vorticity. These spanwise variations are induced by streamwise and normal vortices of opposite directions of rotation. Moreover, measurements were carried out for the cambered plates at α =8°, where a long separation bubble exists, to further understand the behavior of the streamwise and normal vortices. These vortices become more organized and increase in strength and size at the lower angle of attack. It is also speculated that these vortices contribute to the increase in lift at and beyond the onset of stall angle of attack.
Three-Dimensional Modeling of Single Stranded Hairpin DNA Aptamers

Aptamers are short oligonucleotides that are selected for affinity binding to a wide range of targets and provide a number of advantages over antibodies including robustness, low cost, and reusability [1,2]. The relatively simple chemical structure of aptamers allows the insertion of electrochemical or fluorescent reporter molecules as well as surface-binding agents in specific locations on the oligonucleotide. During probe-target binding, the conformation change of the aptamer may be exploited to generate an analytical signal. The robustness and simplicity of aptamers has allowed for multiple uses of aptamer-based biosensors and a number of direct detection strategies employing aptamers have been proposed. However, in order for commercialization of these devices to become feasible, significant improvements in optimization for consistency and reproducibility must be done. Overcoming these challenges has been hampered by a lack of complete understanding of the molecular-level biophysics involved [3]. In this regard, computational studies can complement experimental studies in improving our understanding about the structure, molecular-level interactions, dynamics, and solvent effects of biomolecular complexes [4,5]. Here, we present a method to predict the three-dimensional structure of single stranded DNA aptamers from their sequence.References:[1] Ellington AD & Szostak JW (1990) In vitro selection of RNA molecules that bind specific ligands. Nature 346: 818-822.[2] Liu Y et al. (2010) Aptamer-based electrochemical biosensor for interferon gamma detection. Analytical chemistry 82: 8131-8136.[3] Zhou W et al. (2014) Aptamer-based biosensors for biomedical diagnostics. The Analyst 139: 2627-2640.[4] Saiz L (2012) The physics of protein-DNA interaction networks in the control of gene expression. Journal of Physics: Condensed Matter 24: 193102.[5] Sinha SK & Saiz L (2014) Determinants of protein-ligand complex formation in the thyroid hormone receptor α: a Molecular Dynamics simulation study. Computational and Theoretical Chemistry 1038, 57-66.
Spectroscopic identification of alkoxide, aldehyde, and acyl intermediates in alcohol decomposition on Pd(111)

Abstract The reactions of primary and secondary alcohols were studied on clean Pd(111) surfaces with High Resolution Electron Energy Loss Spectroscopy (HREELS). Emphasis was placed on elucidating the reaction pathways involved in alcohol decomposition and upon determining the influence of different substituents on the stability of adsorbed intermediates. On the clean Pd(111) surface, both primary and secondary alcohols were found to react via decarbonylation pathways. Although the initial step in alcohol activation was alkoxide formation via O-H bond cleavage, the stabilities of the intermediates involved in subsequent reactions differed among the alcohols studied. Methoxides generated by the reaction of methanol underwent selective dehydrogenation to η2(C,O)-formaldehyde species which ultimately decomposed to adsorbed carbon monoxide and hydrogen atoms. Analogous behavior was observed for ethanol and 1-propanol, with the exception that partial dehydrogenation of the η2-aldehyde species derived from these alcohols produced stable acyl intermediates. Decomposition of these higher acyls required temperatures above 260 K and was the rate-limiting step in higher alcohol decomposition. The secondary alcohol 2-propanol reacted via similar pathways, although some desorption of the intermediate dehydrogenation product (acetone) occurred.
Theoretical study of the rovibrationally resolved transitions of CaH

Comprehensive absorption line lists for 40CaH have been calculated for electronic transitions from the X 2Σ+ ground state to the A 2Π, B/B′ 2Σ+, and E 2Π low-lying excited states. The lists include transition energies and oscillator strengths for all possible allowed transitions and were computed using the most recent set of theoretical potential energy curves and dipole transition moment functions, with adjustments to account for experimental dissociation energies and asymptotic limits. Good agreement with previous calculations and available experimental data has been obtained. Oscillator strengths for the transition from the X 2Σ+ state to the D 2Σ+ state are also given, but due to the large uncertainty of the available dipole transition moment function the line list is highly uncertain. For the C 2Σ+←X 2Σ+ transition, a Franck–Condon approximation has been used.
Noninvasive Delineation of Normal Right Ventricular Contractile Motion With Magnetic Resonance Imaging Myocardial Tagging

As the importance of the right ventricle in many diseases and conditions has been realized, the need for quantitative assessment of the motion and contraction of the right ventricular free wall (RVFW) has become apparent. This study applied the myocardial tagging magnetic resonance imaging (MRI) technique to the normal RVFW to elucidate normal heterogeneity in RV motion and contractile patterns. The RVFW was divided into three segments (inferior, mid and superior) in each of three slices (apical, mid and basal) to allow for a detailed analysis of the motion and contraction. Percent segmental shortening (PSS) was used to measure the amount of contraction, and a vector analysis was used to quantitate the trajectory of the RVFW through systole. PSS increased monotonically through time to an average across all segments of 12% in the basal slice, 14% in the mid-ventricular slice, and 16% in the apical slice of the heart. The trajectory of the RVFW was characterized by a wave of motion toward the septum and outflow tract. The data provided in this study provide a better understanding of normal RV kinematics and can serve as a comparison for disease states. © 1998 Biomedical Engineering Society. PAC98: 8759Pw, 0705Pj, 8745Dr
The Regulation of Sugar Uptake and Accumulation in Bean Pod Tissue

The identity, localization and physiological significance of enzymes involved in sugar uptake and accumulation were determined for endocarp tissue of pods of Kentucky Wonder pole beans (Phaseolus vulgaris). An intracellular, alkaline invertase (pH optimum, 8) was assayed in extracted protein, as well as enzymes involved in sucrose synthesis, namely, uridinediphosphate (UDP-glucose pyrophosphorylase and UDP-glucose-fructose transglucosylase). Indirect evidence indicated the presence also of hexokinase, phosphohexoseisomerase and phosphoglucomutase. The data suggested that sucrose synthesis occurred in the cytoplasm, and that both sugar storage and an alkaline invertase occurred in the vacuole. The latter functions to hydrolyze accumulated sucrose. An outer space invertase (pH optimum, 4.0) was detected, but was variable in occurrence. Although its activity at the cell surface enhanced sucrose uptake, sucrose may be taken up unaltered.Over a wide range of concentrations of exogenous glucose the sucrose/reducing sugar ratio of accumulated sugars remained unchanged at about 20. Synthesis of sucrose appears to be requisite to initial accumulation from glucose or fructose, as free hexoses do not increase at the apparent saturating concentration for uptake. Sucrose accumulation from exogenous hexose represents a steady-state value, in which sucrose is transported across the tonoplast into the vacuole at a rate equivalent to its rate of synthesis. Evidence indicates that this component of the accumulation process involves active transport of sucrose against a concentration gradient. The ratio of sucrose/reducing sugars in the accumulated sugars immediately after a period of uptake was inversely related to the level of inner space invertase. Within 16 hours after a period of accumulation, practically all of the sugar occurs as glucose and fructose.The absence of competition among hexoses and sucrose indicated that a common carrier was not involved in their uptake. From a series of studies on the kinetics of uptake of glucose and fructose, including competition studies, the effects of inhibitors, radioactive assay of accumulated sugars and the distribution of label in accumulated sucrose it appeared that rate limitation for glucose or fructose uptake resides in the sequence of reactions leading to sucrose synthesis, rather than in a process mediated by a carrier protein.
Stability constants of iron(III) borate complexes

The ultraviolet absorbance data from experiments conducted at constant pH and total iron concentration but variable B(OH)3 concentration were used to determined the stability constants of FeB(OH)42+ and Fe[B(OH)42+ at 25°C and an ionic strength of 0.68. The estimates obtained were *β1 = 1.0 ± 0.2 × 10−2 and *β2 = 2 ± 1 × 10−5, respectively (uncertainties are two times the standard error of the estimates). A calculation of the extent of iron(III) borate formation in ocean water at pH 8.2 shows that iron(III) borates are not a significantly large component of iron(III) speciation in seawater.
Formal verification of a pipelined microprocessor

The application of modern functional languages and supporting verification technology to a scaled-down but realistic microprocessor is described. The model is of an infinite stream of machine instructions consuming an infinite stream of interrupt signals and is specified at two levels: instruction and hardware design. A correctness criterion is stated for an appropriate sense of equivalent behavior of these levels and proved using a mechanically supported induction argument. The functional-language-based verification system Clio and the Mini Cayuga microprocessor are described. The formal specification and verification process are examined in detail. >
Chloroplast SecA and Escherichia coli SecA Have Distinct Lipid and Signal Peptide Preferences

Like prokaryotic Sec-dependent protein transport, chloroplasts utilize SecA. However, we observe distinctive requirements for the stimulation of chloroplast SecA ATPase activity; it is optimally stimulated in the presence of galactolipid and only a small fraction of anionic lipid and by Sec-dependent thylakoid signal peptides but not Escherichia coli signal peptides.
Midbrain‐hypothalamic interrelationships in the control of aggressive behavior

Previous studies have suggested an involvement of the midbrain ventral tegmental area in the biting attack upon a rat elicited by electrical stimulation of the lateral hypothalamus in cats. In order assess further the relationship between these two regions, 12 cats were implanted with attack-eliciting electrodes in both the lateral hypothalamus and the midbrain ventral tegmental area. Following a lesion of the midbrain attack site, attack previously elicited from hypothalamic electrodes ipsilateral to the lesion was eliminated or significantly reduced in frequency. The attack elicited from electrodes in the hypothalamus contralateral to the lesion was unaffected. Midbrain lesions made at sites from which attack was never elicited had no effect on hypothalamically elicited attack. The midbrain lesion in some cases eliminated only certain components of the total attack pattern; for example, the approach of a cat to the rat frequently remained present while the bite was absent. Additionally, it was found that the attack elicited from rostral hypothalamic electrodes was disrupted to a greater degree by a single midbrain lesion than the attack elicited from more caudal hypothalamic electrodes. These finding are discussed in terms of the neural system mediating this form of aggressive behavior in cats.
Second Malignancies Among Elderly Survivors of Cancer

The U.S. population is aging, life expectancy is increasing, and cancer is a disease associated with aging. Advances in screening and therapeutics have led to a growing number of cancer survivors who are at risk for the development of secondary malignancies. Although the risks for the development of second malignancies following a first diagnosis of cancer are well described for survivors of childhood malignancies, there are fewer data for malignancies common in older adults. With the aging of the U.S. population, and with improving survival statistics in many adult malignancies, there is an increasing need to identify those second malignancies that might develop in the older adult survivor of cancer. In this paper, we describe the types and rates of second malignancies following cancers commonly seen in older adults and review the literature on these malignancies. Comparisons are made between older and younger adults with regard to the risks for developing treatment-related cancers with different modalities. Recommendations for early detection of second malignancies are summarized, though there remains an unmet need for evidence-based guidelines for screening for second malignancies in the older adult in particular.
Prof. MengChu Zhou, New Jersey Institute of Technology [biography]

A biography of Prof. MengChu Zhou (New Jersey Institute of Technology, NJ, USA) is provided.
Oral potentially malignant disorders in a large dental population

Objectives Oral cancer (OC) may be preceded by clinically evident oral potentially malignant disorders (OPMDs). Oral carcinogenesis is a multistep process that begins as epithelial hyperplasia and progresses to oral epithelial dysplasia and finally to fully malignant phenotypes. The aim of our study was to estimate the prevalence of OPMDs in a large population of dental patients. Methods Patients were seen in the Oral Diagnosis and Oral Medicine clinics at Boston University Henry M. Goldman School of Dental Medicine between July 2013 and February 2014 and received a comprehensive oral examination to identify any possible mucosal lesions. Patients with a suspected OPMD (submucous fibrosis, oral lichen planus, leukoplakia and erythroplakia) that did not resolve in 2–3 weeks received a biopsy for definitive diagnosis. Logistic regression models were used to explore the relationship between OPMDs and associated risk factors. Results A total of 3,142 patients received a comprehensive oral examination [median age: 43 (range: 18–97); 54.3% females]. Among these, 4.5% had an oral mucosal lesion with 0.9% being an OPMD (one submucous fibrosis, three epithelial dysplasias, fourteen with hyperkeratosis/epithelial hyperplasia and nine with oral lichen planus). Males and current smokers were associated with higher odds of having OPMD (OR 1.7, 95% CI 0.8–3.8; OR 1.9, 95%CI 0.8–4.1). Increasing age was associated with having OPMDs (p<0.01). Conclusion Optimal oral visual screening for OC remains a simple and essential tool to identify any suspicious lesions and potentially increase survival. Although OPMDs were rare, our results confirm the importance of a thorough chairside screening by dentists and dental students to detect any mucosal changes.
Lessons from prenatal care provider-based recruitment into the National Children’s Study

In response to recruitment difficulties experienced by the National Children’s Study, alternatives to the door-to-door recruitment method were pilot tested. This report describes outcomes, successes, and challenges of recruiting women through prenatal care providers in Benton County, Arkansas, USA. Eligible women residing in 14 randomly selected geographic segments were recruited. Data were collected during pregnancy, at birth, and at 3, 6, 9, 12, 18, and 24 months postpartum. Participants were compared to non-enrolled eligible women through birth records. Of 6402 attempts to screen for address eligibility, 468 patients were potentially eligible. Of 221 eligible women approached to participate, 151 (68%) enrolled in the 21-year study. Enrolled women were similar to non-enrolled women in age, marital status, number of prenatal care visits, and gestational age and birth weight of the newborn. Women enrolled from public clinics were more likely to be Hispanic, lower educated, younger and unmarried than those enrolled from private clinics. Sampling geographic areas from historical birth records failed to produce expected equivalent number of births across segments. Enrollment of pregnant women from prenatal care providers was successful.
Aortic aneurysmal disease: assessment of stent-graft treatment-CT versus conventional angiography.

PURPOSE: To compare computed tomographic (CT) angiography and conventional angiography for determining the success of endoluminal stent-graft treatment of aortic aneurysms. MATERIALS AND METHODS: Forty patients underwent conventional angiography and CT angiography following treatment of aortoiliac aneurysms with endoluminal stent-grafts. Six additional sets of conventional angiographic–CT angiographic examinations were performed in five patients after placement of additional stent-grafts or coil embolization to treat perigraft leakage. Three faculty CT radiologists who were blinded to patient clinical data and outcome independently interpreted the CT angiograms, and three faculty angiographers, who were not involved in the stent-graft deployment, interpreted the conventional angiograms. Images were assessed for the presence of postdeployment complications. A reference standard was developed by experienced radiologists using all available images and clinical data. Sensitivities, specificities, and κ values...
Towards a definition of ecological disturbance

The terms disturbance, perturbation, and stress have been used in various ecological contexts, often synonymously, inconsistently and ambiguously. Consequently, the meaning of these terms lack any ecological rigor upon which to construct a coherent theory of ecosystem response to disturbance. Herein are some of the semantic and conceptual problems involved in defining disturbance, perturbation and stress, and proposals of working definitions as a basis for further discussion.
Using regional comparative phylogeographic data from snake lineages to infer historical processes in Middle America

Understanding how historical processes have either similarly, or differentially, shaped the evolution of lineages or biotic assemblages is important for a broad spectrum of fields. Gaining such understanding can be particularly challenging, however, especially for regions that have a complex geologic and biological history. In this study we apply a broad comparative approach to distill such regional biogeographic perspectives, by characterizing sets of divergence times for major biogeographic boundaries estimated from multiple codistributed lineages of snakes. We use a large combined (mitochondrial gene sequence) phylogeographic/phylogenetic dataset containing several clades of snakes that range across Middle America the tropical region between Mexico and northwestern South America. This region is known for its complex tectonic history, and poorly understood historical biogeography. Based on our results, we highlight how phylogeographic transition zones between Middle and South America and the Nicaragua Depression appear to have undergone multiple episodes of diversification in different lineages. This is in contrast to other examples we find where apparently a single vicariant period is shared across multiple lineages. We specifically evaluate the distributions of divergence time estimates across multiple lineages and estimate the number of temporal periods of lineage diversification per biogeographic break. Overall, our results highlight a great deal of shared temporal divergence, and provide important hypotheses for yet unstudied lineages. These multi-lineage comparisons across multiple spatial and temporal scales provide excellent predictive power for identifying the roles of geology, climate, ecology and natural history in shaping regional biodiversity.
On state-space models for systems described by partial differential equations

New first-order partial differential equation (PDE) representations for systems described by higher order PDEs are proposed. Tools for analysis of lumped-distributed systems are suggested: Mikusi?ski's operational calculus and the 2-D Laplace transform. Next, system equivalence for lumped-distributed systems is defined and discussed. Finally, modal controllability and observability are introduced and compared with the analogous notions for the proper 2-D systems.
Human Autoimmune Sera as Molecular Probes for the Identification of an Autoantigen Kinase Signaling Pathway

Using human autoimmune sera as molecular probes, we previously described the association of phosphorylated serine/arginine splicing factors (SR splicing factors) with the U1-small nuclear ribonucleoprotein (U1-snRNP) and U3-small nucleolar RNP (snoRNP) in apoptotic cells. SR proteins are highly conserved autoantigens whose activity is tightly regulated by reversible phosphorylation of serine residues by at least eight different SR protein kinase kinases (SRPKs), including SRPK1, SRPK2, and the scleroderma autoantigen topoisomerase I. In this report, we demonstrate that only one of the known SRPKs, SRPK1, is associated with the U1-snRNP autoantigen complex in healthy and apoptotic cells. SRPK1 is activated early during apoptosis, followed by caspase-mediated proteolytic inactivation at later time points. SRPKs are cleaved in vivo after multiple apoptotic stimuli, and cleavage can be inhibited by overexpression of bcl-2 and bcl-xL, and by exposure to soluble peptide caspase inhibitors. Incubation of recombinant caspases with in vitro–translated SRPKs demonstrates that SRPK1 and SRPK2 are in vitro substrates for caspases-8 and -9, respectively. In contrast, topoisomerase I is cleaved by downstream caspases (-3 and -6). Since each of these SRPKs sits at a distinct checkpoint in the caspase cascade, SRPKs may serve an important role in signaling pathways governing apoptosis, alternative mRNA splicing, SR protein trafficking, RNA stability, and possibly the generation of autoantibodies directed against splicing factors.
Lysosomal exocytosis and lipid storage disorders

Lysosomes are acidic compartments in mammalian cells that are primarily responsible for the breakdown of endocytic and autophagic substrates such as membranes, proteins, and lipids into their basic building blocks. Lysosomal storage diseases (LSDs) are a group of metabolic disorders caused by genetic mutations in lysosomal hydrolases required for catabolic degradation, mutations in lysosomal membrane proteins important for catabolite export or membrane trafficking, or mutations in nonlysosomal proteins indirectly affecting these lysosomal functions. A hallmark feature of LSDs is the primary and secondary excessive accumulation of undigested lipids in the lysosome, which causes lysosomal dysfunction and cell death, and subsequently pathological symptoms in various tissues and organs. There are more than 60 types of LSDs, but an effective therapeutic strategy is still lacking for most of them. Several recent in vitro and in vivo studies suggest that induction of lysosomal exocytosis could effectively reduce the accumulation of the storage materials. Meanwhile, the molecular machinery and regulatory mechanisms for lysosomal exocytosis are beginning to be revealed. In this paper, we first discuss these recent developments with the focus on the functional interactions between lipid storage and lysosomal exocytosis. We then discuss whether lysosomal exocytosis can be manipulated to correct lysosomal and cellular dysfunction caused by excessive lipid storage, providing a potentially general therapeutic approach for LSDs.
Image Noise and Liver Lesion Detection With MDCT: A Phantom Study

OBJECTIVE. The purpose of this study was to determine the upper limit of noise for detection of small low-contrast lesions in a liver phantom. MATERIALS AND METHODS. A CT liver phantom containing 21 low-contrast, low-attenuation, circular simulated lesions ranging in size from 2.4 to 10 mm was scanned 23 times at different tube current ranges (varying noise index) on a 64-MDCT scanner with automatic tube current modulation. The attenuation of the simulated lesions was 20 HU less than that of the liver-equivalent background. Three radiologists independently reviewed the resultant CT images, which contained either a low-contrast lesion or no lesion and scored certainty of lesion detection using a 4-point Likert scale. Overall performance was evaluated by sensitivity analysis with receiver operator curve and area under the curve (Az) computation for ranges of noise index. RESULTS. The reviewers achieved 100% sensitivity with a noise index of 15 or less for lesions measuring 6.3–10.0 mm (Az = 0.96). Increasin...
Math and Science Pursuits: A Self-Efficacy Intervention Comparison Study:

This study compared two interventions to increase math self-efficacy among undergraduate students. Ninety-nine first-year undergraduate students participated in an intervention involving performance accomplishment or an intervention combining performance accomplishment and belief-perseverance techniques in which participants constructed a rationale for their future success in math/science university courses. As hypothesized, participants in the combined intervention immediately demonstrated higher math self-efficacy than did the Performance-Accomplishment only group; data convey that this effect was sustained at a 6-week follow-up. No differences were found between the groups in interest in technical careers, confidence in successfully completing math/ science courses, and willingness to enroll in math/science courses. Data analyses by gender indicated that male participants but not female participants in the combined intervention immediately demonstrated higher math self-efficacy than their counterparts....
An Anniversary Message

The 1970 meeting of the Economic History Association in Dallas, Texas, marked die organization's thirtieth anniversary. Occasions such as this call for certain ritualistic responsesâ€”as every husband knowsâ€”and the Program Committee was more than willing to satisfy the demands of tradition. Thus our anniversary program included a review of past accomplishments in the various branches of economic history. To balance this review, however, we introduced an element which seldom plays a visible role in the anniversary: a set of resolutions or guidelines for future work in the field. By design, each of the sessions had both a past and future dimension.
Carbon fiber polymer-matrix structural composites exhibiting greatly enhanced through-thickness thermoelectric figure of merit

Abstract The through-thickness thermoelectric behavior of continuous carbon fiber epoxy-matrix composites is greatly improved by adding tellurium particles (13 vol.%), bismuth telluride particles (2 vol.%) and carbon black (2 vol.%). The thermoelectric power is increased from 8 to 163 μV/K, the electrical resistivity is decreased from 0.17 to 0.02.Ω.cm, the thermal conductivity is decreased from 1.31 to 0.51 W/m.K, and the dimensionless thermoelectric figure of merit ZT at 70 °C is increased from 9 × 10 −6 to 9 × 10 −2 . Tellurium increases the thermoelectric power greatly. Bismuth telluride decreases the electrical resistivity and thermal conductivity. Carbon black decreases the electrical resistivity.
Performance Comparison of Two Channel Allocation Strategies in Cellular Networks

Channel allocation plays an important role in increasing the throughput and assuring fairness to users not only in traditional cellular networks but also in cognitive radio networks and mesh networks. In this paper, we study the effect of pre-allocating channels to cells with respect to a distributed and fault-tolerant channel allocation algorithm. Results from our extensive performance evaluation indicate that distributed channel allocation algorithms that pre-allocate all channels to cells can have lower call failure rate, call blocking rate, and handoff drop rate compared to algorithms that partially pre-allocate channels or does not pre-allocate channels.
Fertilization in the Rhesus Monkey

The nonhuman primates occupy a unique niche among species suitable for experimental studies on fertilization and early development. Studies with nonhuman primates provide an important link between the huge literature derived from work on rodents and other common laboratory species and the relatively small amount of data on humans. Research with rodent species continues to provide the bulk of basic information on early development, in large part because of the ready availability of oocytes and embryos, but it is difficult to know to what extent information can be extrapolated to primate species, including humans. Information is increasingly available from the numerous human in vitro fertilization (IVF) programs now in operation. However, the amount and quality of basic scientific data on early development that can be obtained from this source are restricted, in part by ethical constraints (Austin, 1990) and in part by conflicting priorities between research and clinical needs for the supply of oocytes and embryos. For example, most “excess” human IVF embryos in the U.S.A. are destined for cryopreservation or for use in a donor program and are thus unsuitable for any research protocol that might compromise their viability. In contrast, there are no prohibitions on the use of fertilized eggs or embryos of nonhuman primates for research, while the reproductive physiology and embryology of the Old-World nonhuman primates are sufficiently similar to humans that direct extrapolation of concepts is possible.
On Planning an Archives

The planning of an archives should and really must start with the archives staff. They know how they operate and what they need. They know what their workload is, the size of their collection and what both are likely to become. Planning is more than a cumulative total of floorspace multiplied by some factor for future growth. The "square foot credit per item" method is planning in its worst form. Unfortunately, the method is easy to use for a building office preparing an architectural program. Its basic shortcoming is that it does not consider the users. Unfortunately, many architectural firms will accept this method because it is convenient to design by square foot area. Such planning is an example, which lasts a long time and affects many people, of "garbage in, garbage out." Even though the users, in this case the archivists, have the greatest concern and, most important, the insight about what an archives should be, they cannot begin drawing floor plans. There is an important difference between drawing floor plans and expressing ideas about archival space. The former is the function of the architect; it is his job to decide how best to assemble everything into a coherent design. The archivist's function is to use the written language, simply and concisely, to express what the archives does and what its needs are. No special language or techniques are needed, only special effort to be methodical and openminded. Checklists, such as that prepared by the SAA Committee on Buildings and Technical Equipment and reprinted at the end of this article, form a basis for outlining the archival requirements. A consultant can assist by gleaning all the thinking of the staff to ensure that all activities have been considered and by organizing an appropriate system for analyzing their needs. Ideally, there should be no references to conventional measures of planning, such as "square foot area" and "room," because these items
Novel Concept for Gas Injection at Low Pressure in an Effervescent Atomizer

Effervescent atomization is a method involving injecting a small amount of gas into the liquid before it is ejected from an atomizer. This improves atomization by reducing the characteristic liquid dimensions inside the discharge orifice. The atomization process is further enhanced by the rapid expansion of these gas bubbles at the exit that shatters the issuing liquid stream into ligaments and drops. This technique of injecting gas directly into the liquid stream inside the atomizer body leads to smaller ejected drop size and uniform spray pattern. Despite its advantages over conventional atomizers, there is a limitation in effervescent atomizers due to the requirement of injecting gas at higher pressure than the liquid itself, which is already at relatively high pressure. This requirement leads to practical application trade-offs. In order overcome this drawback, the working principle of an ejector pump is utilized for gas entrainment into liquid stream at pressures lower than that of the pressurized liquid. This may also lead to gas injection pressure even lower than the ambient atmospheric pressure. The parameters of this new concept effervescent atomizer, i.e. based on ejector pump principle, are selected to conform to general effervescent atomizer data available in literature. The feasibility of this novel concept is first determined by ejector pump analytical analysis techniques (ESDU 85032) and later by CFD analysis. The results indicate that this concept is feasible and gas can be injected into a pressurized liquid stream of an effervescent atomizer at markedly low pressures, without the need of a separate gas pumping arrangement. This concept also affords design flexibility for diversified application by modifying the ejector pump parameters. The patent for the design presented in this paper is submitted for approval [11].
Oviposition and Development of the Navel Orangeworm in Relation to Almond Maturation

Under orchard conditions, oviposition by Paramyelois transitella (Walker) begins on maturing almond fruit just prior to initiation of hull-split. After hull-split is complete, half the eggs are laid within the opened area on the inside of the hull or on the exposed shell, the rest on the outside of the hull. Moths preferentially oviposit on previously infested fruit, as compared with uninfested fruit. Infestation develops explosively after dehiscence begins. Most of the larvae hatching during the early stages of hull-split infest the nutmeat directly rather than feeding on the hull. Preventive treatments during this period should be applied before significant hull-split has taken place. Development of the navel orangeworm in new crop fruit in situ was followed by sampling 3 cohorts of dehiscing fruit artificially infested with eggs of a known age. By applying data developed on width of the larval head capsule to these populations, sampled in sequence, development was charted providing estimates of stadial length. First emergence from the new crop occurred in 29 days, in time to cause reinfestation. Fifty % emergence occurred in 42–45 days.
Ultrafast Photodissociation Dynamics of Nitromethane

Nitromethane (NM), a high explosive (HE) with low sensitivity, is known to undergo photolysis upon ultraviolet (UV) irradiation. The optical transparency, homogeneity, and extensive study of NM make it an ideal system for studying photodissociation mechanisms in conventional HE materials. The photochemical processes involved in the decomposition of NM could be applied to the future design of controllable photoactive HE materials. In this study, the photodecomposition of NM from the nπ* state excited at 266 nm is being investigated on the femtosecond time scale. UV femtosecond transient absorption (TA) spectroscopy and excited state femtosecond stimulated Raman spectroscopy (FSRS) are combined with nonadiabatic excited state molecular dynamics (NA-ESMD) simulations to provide a unified picture of NM photodecomposition. The FSRS spectrum of the photoproduct exhibits peaks in the NO2 region and slightly shifted C-N vibrational peaks pointing to methyl nitrite formation as the dominant photoproduct. A total photolysis quantum yield of 0.27 and an nπ* state lifetime of ∼20 fs were predicted from NA-ESMD simulations. Predicted time scales revealed that NO2 dissociation occurs in 81 ± 4 fs and methyl nitrite formation is much slower having a time scale of 452 ± 9 fs corresponding to the excited state absorption feature with a decay of 480 ± 17 fs observed in the TA spectrum. Although simulations predict C-N bond cleavage as the primary photochemical process, the relative time scales are consistent with isomerization occurring via NO2 dissociation and subsequent rebinding of the methyl radical and nitrogen dioxide.
Characterizing performance of residential internet connections using an analysis of measuring broadband America's web browsing test data

Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, Institute for Data, Systems, and Society, Technology and Policy Program, 2015.
Primary functional analysis of a novel SCN5A mutation A1180V

Objective We reported a novel SCN5A mutation A1180V in a pedigree with dilated cardiomyopathy and progressive cardiac conduction defect.Herein the primary functional analysis of the novel mutation has been made in order to find the underlying association between the genotype and phenotype. Methods The wild-type and mutated SCN5A cDNA were transiently transfeeted into HEK293 cells which can stably express theβsubunit of the human sodium channel.Patch-clamp recordings were performed 48 to 64 hours after transfeetion.We calculated voltage dependencies of activation and steady-state inactivation and quantified time courses of inactivation and recovery from inactivation.Results Compared with wild-type ehannels,we found the mutated channels exhibited a similar activation but a -4.5mV shift of inactivation with slower recovery leading to a rate-dependent sodium current reduction,and the mutated channels had an increase in late sodium current.Conclusion A1180V mutation expresses a mild sodium channel phenotype in vitro,implying that A1180V caused structural heart disease by disturbing sodium influx and,hence,cel- lular sodium homeostasis.
Cloning of a rabbit kidney cortex AT1 angiotensin II receptor that is present in proximal tubule epithelium

The rabbit proximal tubule (PT) has been widely utilized to study the direct effects of angiotensin II (ANG II) on PT function. The purpose of the present study was to characterize the binding properties of PT ANG II receptors, using nonpeptide antagonists, and to clone a rabbit PT ANG II receptor. In rat and rabbit kidney cortical brush-border and basolateral membranes, specific binding of 125I-ANG II was inhibited by the AT1 ANG II-receptor antagonist DuP 753, but not by the AT2 antagonist PD 123319. Using a rabbit kidney cortex cDNA library, we isolated cDNA encoding an ANG II receptor, with an open-reading frame sharing a high degree of sequence homology to previously cloned AT1 ANG II receptors. In transfected COS-1 cells, this rabbit ANG II receptor had properties of the AT1 class. Northern analysis revealed high levels of mRNA expression for this receptor in rabbit kidney cortex and adrenal gland. Within the kidney, message was detected in primary cultures of rabbit PT cells, as well as in freshly isolated rabbit PT segments. Message was also present in cells of the mouse PT line, MCT, and in rat glomerular mesangial cells. Utilizing polymerase chain reaction (PCR) with primers derived from the 1st and 4th transmembrane domains of the rat AT1A ANG II receptor, a 279-bp DNA fragment was amplified from reverse-transcribed RNA from rabbit PT cells. This DNA encoded an amino acid sequence identical to that encoded by the rabbit kidney cDNA clone in the corresponding region and differed by a single base substitution. Southern analysis of rabbit genomic DNA restriction digests with the rabbit ANG II receptor probe revealed hybridization to a single band in each lane. These results indicate that an AT1 ANG II receptor is present in the PT and that a single gene codes for the AT1 receptor in rabbit. The clone isolated in the present study should provide a useful tool with which to study the regulation of the PT renin-angiotensin system.
Concept of an upright wearable positron emission tomography imager in humans.

Background Positron Emission Tomography (PET) is traditionally used to image patients in restrictive positions, with few devices allowing for upright, brain-dedicated imaging. Our team has explored the concept of wearable PET imagers which could provide functional brain imaging of freely moving subjects. To test feasibility and determine future considerations for development, we built a rudimentary proof-of-concept prototype (Helmet_PET) and conducted tests in phantoms and four human volunteers. Methods Twelve Silicon Photomultiplier-based detectors were assembled in a ring with exterior weight support and an interior mechanism that could be adjustably fitted to the head. We conducted brain phantom tests as well as scanned four patients scheduled for diagnostic F18-FDG PET/CT imaging. For human subjects the imager was angled such that field of view included basal ganglia and visual cortex to test for typical resting-state pattern. Imaging in two subjects was performed ~4 hr after PET/CT imaging to simulate lower injected F18-FDG dose by taking advantage of the natural radioactive decay of the tracer (F18 half-life of 110 min), with an estimated imaging dosage of 25% of the standard. Results We found that imaging with a simple lightweight ring of detectors was feasible using a fraction of the standard radioligand dose. Activity levels in the human participants were quantitatively similar to standard PET in a set of anatomical ROIs. Typical resting-state brain pattern activation was demonstrated even in a 1 min scan of active head rotation. Conclusion To our knowledge, this is the first demonstration of imaging a human subject with a novel wearable PET imager that moves with robust head movements. We discuss potential research and clinical applications that will drive the design of a fully functional device. Designs will need to consider trade-offs between a low weight device with high mobility and a heavier device with greater sensitivity and larger field of view.