cssi/SciSciGPT-SciSciNet huggingface dataset:
Experimental measurement of thermal diffusivity, conductivity and specific heat capacity of metallic powders at room and high temperatures

Abstract Because of the complications associated with metal additive manufacturing process, comprehensive modeling is done to improve the process. Thermo-physical properties such as heat capacity, thermal conductivity and diffusivity of metallic powder is very crucial for the models to be accurate. Due to challenges associated with measuring these properties at high temperature, available analytical models are often used to determine these temperature dependent thermo-physical properties. This study is conducted to fill this gap and provide experimental information that has been missing from the bulk of the literature for variety of metallic powders commonly used in additive manufacturing processes. Additionally, a comparison between these experimental data and analytical models are conducted to determine the correlation and accuracy of these models. Analysis revealed that all the thermal properties of the powders show a non-monotonic behavior at high temperature. A regression analysis is conducted to predict thermal conductivity at higher temperatures.
Selective Effects of Ethanol on Neuropeptide — Mediated Polyphosphoinositide Hydrolysis and Calcium Mobilization

The cell-surface receptor activation of phospholipase C and the subsequent production of 1,4,5 trisphosphate and diacylglycerol and intracellular calcium mobilization is a key signal transduction system utilized by brain as well as many peripheral tissues (for review, see Fisher et al, 1992). The role of phospholipase C as a mediator of ethanol actions in brain has been the subject of several investigations (Gonzales et al, 1986; Hoffman et al, 1986; Smith et al, 1986). These studies focused on the activation of PLC by classical neurotransmitters such as norepinephrine histamine, and acetylcholine. However, very little information is available regarding the possible effects of chronic ethanol on neuropeptide -stimulated PLC and subsequent calcium mobilization in neural tissues. This laboratory has recently reported that chronic ethanol significantly reduced the stimulation of [3H] inositol phosphates production by bradykinin (Smith, 1991). In the present report, possible mechanisms for this down-regulated response were examined in N1E-115 neuroblastoma cells. Although neuroblastoma are transformed cells, they retain many neural properties (Bozou et al, 1986; Monck et al, 1990; Twombly et al, 1990; Milligan et al, 1990) and, therefore, represent a suitable model system to study alterations in signal transduction, thus avoiding the inherent complexity and heterogeneity of cell populations within brain tissues.
Is long travel distance a barrier to surgical cancer care in the United States? A systematic review.

Abstract Background Travel distance to surgical cancer care is increasing. The relationship between increased travel distance and receipt of surgical cancer care in the United States is not well characterized. Methods A systematic review of studies examining travel distance and receipt of surgery for adult patients in the United States was performed. Literature searches were conducted using PubMed and EMBASE. Results Seven studies were included. Only one found lower likelihood of surgery with increasing travel distance. Three studies, all based on hospital-based data, found that increased travel distance was associated with a higher likelihood of receiving surgery. Two studies found no association and one study had mixed findings. Conclusion We were unable to identify a consistent relationship between travel distance and receipt of surgery. Our results highlight the need for additional research examining how increasing travel distance impacts receipt of surgical cancer care.
Fulminant COVID-19-Associated Myocarditis in an Otherwise Healthy Female

An outbreak of a severe respiratory illness caused by a novel coronavirus that began in China in late 2019 has become a pandemic. We report the case of COVID-19-associated myocarditis in a 45-year-old healthy female who presented with solely gastrointestinal symptoms. Initial investigations revealed ST-segment elevations in her electrocardiogram (EKG), elevated troponin levels, and a positive severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) reverse transcription-polymerase chain reaction (RT-PCR). Subsequently, she had rapid deterioration with the development of cardiogenic shock within hours of admission to a community hospital in Massachusetts. This case highlights an atypical presentation of COVID-19 with a fulminant course in this emerging and evolving disease.
Evidence that synaptic plasticity of glutamatergic inputs onto KNDy neurones during the ovine follicular phase is dependent on increasing levels of oestradiol

Neurones in the arcuate nucleus co-expressing kisspeptin, neurokinin B (NKB) and dynorphin (KNDy) play a critical role in the control of gonadotrophin-releasing hormone (GnRH) and luteinising hormone (LH) secretion. In sheep, KNDy neurones mediate both steroid-negative- and -positive-feedback during pulsatile and preovulatory surge secretions of GnRH/LH, respectively. In addition, KNDy neurones receive glutamatergic inputs expressing vGlut2, a glutamate transporter that serves as a marker for those terminals, from both KNDy neurones and other populations of glutamatergic neurones. Previous work reported higher numbers of vGlut2-positive axonal inputs onto KNDy neurones during the LH surge than in luteal phase ewes. In the present study, we further examined the effects of the ovarian steroids progesterone (P) and oestradiol (E2 ) on glutamatergic inputs to KNDy neurones. Ovariectomised (OVX) ewes received either no further treatment (OVX) or steroid treatments that mimicked the luteal phase (low E2 + P), and early (low E2 ) or late follicular (high E2 ) phases of the oestrous cycle (n = 4 or 5 per group). Brain sections were processed for triple-label immunofluorescent detection of NKB/vGlut2/synaptophysin and analysed using confocal microscopy. We found higher numbers of vGlut2 inputs onto KNDy neurones in high E2 compared to the other three treatment groups. These results suggest that synaptic plasticity of glutamatergic inputs onto KNDy neurones during the ovine follicular phase depend on increasing levels of E2 required for the preovulatory GnRH/surge. These synaptic changes likely contribute to the positive-feedback action of oestrogen on GnRH/LH secretion and thus the generation of the preovulatory surge in the sheep.
Hippocampal ripples signal contextually-mediated episodic recall

High-frequency oscillatory events, termed ripples, represent synchrony of neural activity in the brain1. Experiments in animal models have characterized ripples during quiescent and sleep states1 and to a lesser degree during active behavior2-4. Converging evidence from these animal studies5,computational modeling6, and recent examinations in human participants support a link between hippocampal7-9 or medial temporal lobe (MTL)10,11 ripples and memory retrieval. Analyzing direct MTL recordings from 219 neurosurgical participants performing episodic recall tasks, we ask whether ripples specifically reflect the reinstatement of contextual information12-14, a defining property of episodic memory12,15, and are not just a recapitulation of recently-experienced stimuli7,10. Here we find that the rate of hippocampal ripples rises just prior to the free recall of recently-formed memories. This pre-recall ripple effect appears most strongly in the CA1 and dentate gyrus (DG) subfields of hippocampus--regions critical for episodic memory16-18. Neighboring entorhinal and parahippocampal cortices exhibit a significantly weaker effect. The pre-recall ripple effect is strongest prior to the retrieval of semantically- and/or temporally-related recalls, indicating the involvement of ripples in contextual reinstatement, thereby specifically linking ripples with retrieval of episodic memories.
RVMA: Remote Virtual Memory Access

Remote Direct Memory Access (RDMA) capabilities have been provided by high-end networks for many years, but the network environments surrounding RDMA are evolving. RDMA performance has historically relied on using strict ordering guarantees to determine when data transfers complete, but modern adaptively-routed networks no longer provide those guarantees. RDMA also exposes low-level details about memory buffers: either all clients are required to coordinate access using a single shared buffer, or exclusive resources must be allocatable per-client for an unbounded amount of time. This makes RDMA unattractive for use in many-to-one communication models such as those found in public internet client-server situations.Remote Virtual Memory Access (RVMA) is a novel approach to data transfer which adapts and builds upon RDMA to provide better usability, resource management, and fault tolerance. RVMA provides a lightweight completion notification mechanism which addresses RDMA performance penalties imposed by adaptively-routed networks, enabling high-performance data transfer regardless of message ordering. RVMA also provides receiver-side resource management, abstracting away previously-exposed details from the sender-side and removing the RDMA requirement for exclusive/coordinated resources. RVMA requires only small hardware modifications from current designs, provides performance comparable or superior to traditional RDMA networks, and offers many new features.In this paper, we describe RVMA’s receiver-managed resource approach and how it enables a variety of new data-transfer approaches on high-end networks. In particular, we demonstrate how an RVMA NIC could implement the first hardware-based fault tolerant RDMA-like solution. We present the design and validation of an RVMA simulation model in a popular simulation suite and use it to evaluate the advantages of RVMA at large scale. In addition to support for adaptive routing and easy programmability, RVMA can outperform RDMA on a 3D sweep application by 4.4X.
Specialized computational methods for denoising, B 1 correction, and kinetic modeling in hyperpolarized 13 C MR EPSI studies of liver tumors.

PURPOSE To develop a novel post-processing pipeline for hyperpolarized (HP) 13 C MRSI that integrates tensor denoising and B1+ correction to measure pyruvate-to-lactate conversion rates (kPL ) in patients with liver tumors. METHODS Seven HP 13 C MR scans of progressing liver tumors were acquired using a custom 13 C surface transmit/receive coil and the echo-planar spectroscopic imaging (EPSI) data analysis included B0 correction, tensor rank truncation, and zero- and first-order phase corrections to recover metabolite signals that would otherwise be obscured by spectral noise as well as a correction for inhomogeneous transmit ( B1+ ) using a B1+ map aligned to the coil position for each patient scan. Processed HP data and corrected flip angles were analyzed with an inputless two-site exchange model to calculate kPL . RESULTS Denoising averages SNR increases of pyruvate, lactate, and alanine were 37.4-, 34.0-, and 20.1-fold, respectively, with lactate and alanine dynamics most noticeably recovered and better defined. In agreement with Monte Carlo simulations, over-flipped regions underestimated kPL and under-flipped regions overestimated kPL . B1+ correction addressed this issue. CONCLUSION The new HP 13 C EPSI post-processing pipeline integrated tensor denoising and B1+ correction to measure kPL in patients with liver tumors. These technical developments not only recovered metabolite signals in voxels that did not receive the prescribed flip angle, but also increased the extent and accuracy of kPL estimations throughout the tumor and adjacent regions including normal-appearing tissue and additional lesions.
An Explication of Identity Shift Theory

Abstract. First articulated in 2008, the concept of identity shift refers to the process of self-transformation that is the result of intentional self-presentation in a mediated context. As researc...
Ion source development for ultratrace detection of uranium and thorium

Abstract Efficient ion sources are needed for detecting ultratrace U and Th impurities in a copper matrix by mass spectrometry techniques such as accelerator mass spectrometry (AMS). Two positive ion sources, a hot-cavity surface ionization source and a resonant ionization laser ion source, are evaluated in terms of ionization efficiencies for generating ion beams of U and Th. The performances of the ion sources are characterized using uranyl nitrate and thorium nitrate sample materials with sample sizes between 20 and 40 μg of U or Th. For the surface ion source, the dominant ion beams observed are UO + or ThO + and ionization efficiencies of 2–4% have been obtained with W and Re cavities. With the laser ion source, three-step resonant photoionization of U atoms has been studied and only atomic U ions are observed. An ionization efficiency of about 9% has been demonstrated. The performances of both ion sources are expected to be further improved.
INFORMATION TECHNOLOGY FOR FREIGHT TRANSPORTATION COORDINATION

In intermodal transport, an information transfer between carriers and possibly a terminal or port must occur before the physical transfer can be done. That is, the receiving carrier, and possibly the operator of the transfer point, must be able to view information about the shipment before it is able to move the shipment onward. The ability to share information between these parties and to view information about the shipment while the shipment is in transit is critical to improving the coordination of freight transportation. Visibility is also the key to effective customer service. The objective of this paper is to determine what types of communications and information technology (IT) applications are needed to enhance the service and reliability of freight transportation. The focus is on how IT applications can be used by different actors involved in freight transportation to fulfill their coordination roles. The basic principle followed is that, in addition to supporting the operational aspects, each actor has expertise in one or more essential roles, and IT can be used to provide incentives for the performance of those roles. Thus, IT is not only valuable for support but also for coordination. Examples of successful use of IT in freight transportation are presented first. Next, estimates of the potential savings that straightforward applications of IT to transportation can have on freight transportation expenditures are discussed, and the microeconomic basis for these benefits is explained. How future gains from IT are likely to come from the coordination of transportation and the supply chain is examined, and the information components needed for this coordination are described. The type of organization and network arrangements needed to support transport for the supply chain is studied, and the state of the most extensive IT initiative, electronic data interchange (EDI), is discussed. Finally, ways in which government policy can be modified to increase efficiency in the transportation sector are suggested.
Ceftizoxime: A Beta‐Lactamase‐Stable, Broad‐Spectrum Cephalosporin

Ceftizoxime is an iminomethoxy aminothiazolyl cephalosporin that inhibits a wide variety of aerobic, anaerobic gram-positive and gram-negative bacteria. The majority of Enterobacteriaceae are inhibited by less than or equal to 1 microgram/ml as are streptococcal species with the exception of Streptococcus faecalis. Staphylococcus aureus are inhibited by 3-8 micrograms/ml, while methicillin-resistant. aureus are resistant. Bacteroides fragilis are inhibited by 16-64 micrograms/ml. It inhibits Pseudomonas aeruginosa at usually achievable concentrations. Ceftizoxime is overall similar in antibacterial activity to cefotaxime and moxalactam. Ceftizoxime is not hydrolyzed by common plasmid and chromosomal beta-lactamases. Serum levels of ceftizoxime after intramuscular and intravenous injection are similar to those of cefotaxime and moxalactam. The half-life is 1.6 to 1.9 hours in normal individuals. The compound is not metabolized and is cleared from the body by glomerular filtration. Ceftizoxime enters most body fluids, including the cerebrospinal fluid, to produce therapeutic concentrations against clinically important bacteria. Ceftizoxime accumulates in the presence of renal failure, but it is removed from the body by hemodialysis and peritoneal dialysis. Ceftizoxime has proved to be an effective chemotherapeutic agent when used as treatment for pneumonia, urinary tract infections, osteomyelitis, septic arthritis, meningitis, peritonitis, gonorrhea, including penicillinase-producing isolates, and gynecological infections. No major adverse reactions have been associated with the use of ceftizoxime and it has produced neither disulfram -like reactions nor bleeding.
Finding the function buried in SAND.

The SAND domain is present in many proteins that have been linked to chromatin-dependent transcriptional regulation and human disease, but their function has remained unknown. Recent studies have revealed that these modules are DNA binding domains of novel molecular structure.
Subunit structure of L-ribulokinase from Escherichia coli.

Abstract l-Ribulokinase from Escherichia coli B/r has a molecular weight of 98,000 by sedimentation-diffusion, sedimentation equilibrium, and osmotic pressure measurements. Protonation of l-ribulokinase or treatment with 8 m urea results in the dissociation of the native enzyme into two subunits of molecular weight 49,500 (pH 2.0) and 50,200 (urea). The subunits are identical by size and charge, as evidenced by their sedimentation and electrophoretic behavior. Both subunits appear to have masked N-terminal end groups. There are 14 methionine residues per molecule of native l-ribulokinase, and after cleavage with cyanogen bromide we observed 7 bands by electrophoresis in acrylamide gels. All evidence is consistent with l-ribulokinase being a dimer of identical polypeptide chains.
TNFR-Associated Factor 6 and TGF-β–Activated Kinase 1 Control Signals for a Senescence Response by an Endosomal NK Cell Receptor

The endosomal innate receptor CD158d (killer cell Ig-like receptor 2DL4) induces cellular senescence in human NK cells in response to soluble ligand (HLA-G or agonist Ab). These senescent NK cells display a senescence-associated secretory phenotype, and their secretome promotes vascular remodeling and angiogenesis. To understand how CD158d initiates signaling for a senescence response, we mapped the region in its cytoplasmic tail that controls signaling. We identified a conserved TNFR-associated factor 6 (TRAF6) binding motif, which was required for CD158d-induced NF-κB activation and IL-8 secretion, TRAF6 association with CD158d, and TRAF6 recruitment to CD158d+ endosomes in transfected cells. The adaptor TRAF6 is known to couple proximal signals from receptors such as endosomal TLRs and CD40 through the kinase TGF-β–activated kinase 1 (TAK1) for NF-κB–dependent proinflammatory responses. Small interfering RNA–mediated silencing of TRAF6 and TAK1, and inhibition of TAK1 blocked CD158d-dependent IL-8 secretion. Stimulation of primary, resting NK cells with soluble Ab to CD158d induced TRAF6 association with CD158d, induced TAK1 phosphorylation, and inhibition of TAK1 blocked the CD158d-dependent reprogramming of NK cells that produces the senescence-associated secretory phenotype signature. Our results reveal that a prototypic TLR and TNFR signaling pathway is used by a killer cell Ig-like receptor that promotes secretion of proinflammatory and proangiogenic mediators as part of a unique senescence phenotype in NK cells.
Distinct order of Gd 4 f and Fe 3 d moments coexisting in Gd Fe 4 Al 8

Single crystals of flux-grown tetragonal $\mathrm{Gd}{\mathrm{Fe}}_{4}{\mathrm{Al}}_{8}$ were characterized by thermodynamic, transport, and x-ray resonant magnetic scattering measurements. In addition to antiferromagnetic order at ${T}_{N}\ensuremath{\approx}155\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, two low-temperature transitions at ${T}_{1}\ensuremath{\approx}21\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ and ${T}_{2}\ensuremath{\approx}27\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ were identified. The Fe moments order at ${T}_{N}$ with an incommensurate propagation vector $(\ensuremath{\tau},\ensuremath{\tau},0)$ with $\ensuremath{\tau}$ varying between 0.06 and 0.14 as a function of temperature, and maintain this order over the entire $Tl{T}_{N}$ range. The Gd $4f$ moments order below ${T}_{2}$ with a ferromagnetic component mainly out of plane. Below ${T}_{1}$, the ferromagnetic components are confined to the crystallographic plane. Remarkably, at low temperatures the Fe moments maintain the same modulation as at high temperatures, but the Gd $4f$ moments apparently do not follow this modulation. The magnetic phase diagrams for fields applied in [110] and [001] direction are presented and possible magnetic structures are discussed.
Detecting and compressing dissolve regions in video sequences with a DVI multimedia image compression algorithm

It is common practice in video production to use a dissolve region to concatenate two scenes. When the images in such a region are compressed with a motion compensation-based algorithm such as the DVI PLV2.0, blockiness may occur whenever the prediction error images are not allocated the desired number of bits. These artifacts can be eliminated by first detecting, then handling the frames in a dissolve region in the proper way. A dissolve detector and dissolve handling mechanism are developed. The dissolve detector exploits the parabolic behavior of the variances of the frames in a dissolve region. The detected dissolve frames are subsampled vertically, then compressed. >
The 5-hydroxytryptamine2 agonist, (±)-1-(2,5-dimethoxy-4-bromophenyl)-2-aminopropane stimulates the hypothalamic-pituitary-adrenal (HPA) axis. II: Biochemical and physiological evidence for the development of tolerance after chronic administration

In order to investigate the long term effects of the 5-hydroxytryptamine2 (5-HT2) receptor agonist, (+-)-1-(2,5-dimethoxy-4-bromophenyl)-2-aminopropane (DOB), on hypothalamic-pituitary-adrenal (HPA) axis activity, DOB (0.35 mg/kg/day) was administered via osmotic minipumps to rats for 7 days at which time plasma adrenocorticotrophic hormone (ACTH), corticosterone and regional brain corticotropin-releasing factor (CRF) concentrations were measured. In addition, anterior pituitary CRF and frontal cortical 5-HT2 receptor binding was measured. Seven-day infusion of DOB resulted in tolerance to the stimulatory actions of the drug on the HPA axis as evidenced by the return of plasma ACTH and corticosterone concentrations to base-line values. Moreover, rats treated chronically with DOB exhibited decreased numbers of both anterior pituitary CRF and cortical and hypothalamic 5-HT2 receptor. These receptor changes were physiologically significant as challenges doses of DOB or CRF resulted in blunted ACTH responses. Chronic DOB infusion was without effect on CRF concentrations in all hypothalamic and extrahypothalamic brain regions studied. A series of time course experiments revealed that DOB-induced increases in plasma corticosterone returned to base-line by 2-days postimplantation. This effect was apparently associated with down-regulation of the 5-HT2 receptor because high-affinity cortical [3H]DOB and hypothalamic (+-)-[125I]-1-(2,5-dimethoxy-4-iodophenyl)-2-amino-propane binding were decreased at this time as well. Although median eminence CRF content was unchanged at all time points, anterior pituitary CRF receptor binding was significantly decreased 7 days postimplantation.(ABSTRACT TRUNCATED AT 250 WORDS)
The fracture toughness of a particulate-reinforced brittle matrix

Abstract An analytical modeling approach capable of evaluation of principal micromechanical processes taking place in brittle matrix composites reinforced by ductile particles is presented. The model addresses the effects associated with discrete particle distribution and particle—matrix interface properties. As is well known, the reinforcing mechanism is based on formation of a system of restrictive forces imposed on the crack surfaces by the plastic particles behind the propagating crack front. The particles form a bridging zone and, thus, constrain the crack opening. This is the principal aspect of the toughening mechanism in these systems. The analytical approach is based on these physical features; it enforces the natural stress state surrounding the particles and the constant volume plastic flow of the particles, and does not rely on an approximation of the stress-crack opening displacement relationship of the representative cell. The analysis allows one to trace the crack propagation through this system. This detailed analysis explains certain aspects of the particulate reinforcement mechanism not discussed in the literature previously. The resistance curves are presented for several composite systems.
Fructose transport mechanisms in humans

Abstract BACKGROUND & AIMS: The possible mechanisms of fructose transport are diffusion, a disaccharidase-related transport system, and glucose- facilitated fructose transport. However, these mechanisms in the human small intestine have not been systematically examined. This study was designed to investigate the mechanisms of fructose transport in the human duodenojejunum. METHODS: A triple-lumen tube was fluoroscopically positioned in the duodenojejunum of 7 men. Nine carbohydrate- electrolyte solutions were perfused at the rate of 15 mL/min. Acarbose and lactulose were used to examine the disaccharidase-related transport system and glucose-facilitated fructose transport, respectively. RESULTS: Fructose absorption was greater (P CONCLUSIONS: Fructose is transported transcellularly by facilitated diffusion and paracellularly (based on lactulose transport) via glucose- activated solution drag. In the human small intestine, free fructose and glucose transport does not occur via the disaccharidase system. (Gastroenterology 1997 Oct;113(4):1171-9)
Care for the Adult Family Members of Victims of Unexpected Cardiac Death

More than 300,000 sudden coronary deaths occur annually in the United States, despite declining cardiovascular death rates. In 2000, deaths from heart disease left an estimated 190,156 new widows and 68,493 new widowers. A major unanswered question for emergency providers is whether the immediate care of the loved ones left behind by the deceased should be a therapeutic task for the staff of the emergency department in the aftermath of a fatal cardiac arrest. Based on a review of the literature, the authors suggest that more research is needed to answer this question, to assess the current immediate needs and care of survivors, and to find ways to improve care of the surviving family of unexpected cardiac death victims. This would include improving quality of death disclosure, improving care for relatives during cardiopulmonary resuscitation of their family member, and improved methods of referral for services for prevention of psychological and cardiovascular morbidity during bereavement.
The costs of axonal communication

Previously we evaluated the metabolic cost inherent in action potential velocity and found squid sodium channel density to be at an energy-efficient, optimal level [1]. However, in addition to velocity it is sensible to conjecture that metabolic energy must also pay for information transmission. Indeed Levy and Baxter [2] used an optimization perspective that demonstrated the average firing rate of forebrain cortical neurons corresponds to an optimized value of bits per unit of metabolic energy. These two distinct optimizations force us to ask: (1) Are these two optimizations distinct, and (2) how – in the biophysical sense – has Nature (natural selection) addressed these two optimizations. The key insight, which can be seen in [3], is that a substantial fraction of metabolic energy must be devoted to ion fluxes that seem to do nothing. Specifically, the overlapping sodium and potassium currents are neutralizing but the ion fluxes themselves must, eventually, be reversed by the Na-K ATPase pump. We will present biophysical simulations showing that velocity and the energy devoted to velocity can be separated from the energy devoted to information. At the heart of this answer is the presumed ability of Nature to evolve voltage-dependent potassium channels with a range of possible onset delays and the possibility of action potentials that need little if any voltage-dependent potassium channels. When we create a variable artificial delay of potassium channel activation, we affect both the information rate and the metabolic costs with little or no effect on velocity or its cost. In particular, by altering the delay of the voltage-dependent potassium conductance, we alter the neutralized currents without altering the sodium current of the wave front. Thus nature can independently evolve signalling systems that pay for velocity and independently pay for information. The cost of higher information rates is an increasing function of neutralized currents. Thus we conclude the two optimizations are separately evolvable and it is easy to identify distinct examples in nature.
Numerical investigation of FAST powder consolidation of Al2O3 and additive free β-SiC

In this work we examine ceramic synthesis through powder consolidation and the field assisted sintering technique. In particular, we investigate the sintering of Al2O3 and additive free from both an experimental and numerical perspective. For the numerical model, the continuum theory of sintering model is employed, and the densification mechanisms corresponding to power law creep and grain boundary diffusion are considered. Experiments are used for comparison and validation purposes. The results indicate that in general, the densification kinetics simulated by the numerical model compare favorably with the experimental results. Parametric studies involving initial grain size, heating rate, and applied stress are also examined using the numerical model, and confirm many of the expected results from previous research, including increased densification due to higher heating rates, smaller grain sizes, and increased applied loading conditions.
Fate of Zinc Ammonia Acetate in Soils and Its Uptake by Corn

ABSTRACT Zinc ammonium acetate (ZAA) is applied to soil with anhydrous ammonia as a carrier to improve corn (Zea mays L.) productivity. To study the fate of ZAA in the soils, a laboratory leaching experiment was conducted with 14C-ZAA and 65Zn-ZAA using water or NH4OH as carrier. Results showed that ZAA degraded in the soil and released CO2. The released CO2 was from the acetate component of ZAA and accounted for less than 0.06% of the total applied 14C. Using H2O as carrier resulted in more CO2 release than using NH4OH, regardless of soil type. However, more 14C was detected in the leachate when using NH4OH as a carrier than when using H2O. A plant uptake experiment using 14C-ZAA and 65Zn-ZAA indicated that four-leaf-stage corn seedlings absorbed higher amounts of 14C in the stem and root than in the leaves. The 65Zn was detected in most tested plant parts. Our study showed that ZAA enhanced cytokinin levels in root and/or shoot tissues of corn seedlings, suggesting a secondary regulatory effect of ZAA i...
THE RELATIONSHIP OF SELF-EFFICACY, SELF-REGULATION, AND COLLABORATIVE VERBAL BEHAVIOR WITH GRADES: PRELIMINARY FINDINGS

In this study, we sought preliminary information about the relationships among measures of self-efficacy, self-regulation, collaborative learning behavior, and grades. The collaborative verbal behavior of 20 students in a computer course was observed. Also, students responded to a questionnaire to assess their academic self-efficacy. A teacher rated each student's self-regulated learning behaviors. The measures were taken at various points throughout the school year, and the data were analyzed using path analysis. Although students scoring higher on self-regulation tended to score higher also on the measures of collaborative verbal behavior than did those who scored lower on self-regulation, scores on self-regulation rather than on verbal engagement were correlated with grades. The findings were discussed in the light of social cognitive theory and recommendations were made for further study.
Multiple myeloma: clinical features and indications for therapy.

Multiple myeloma is a malignant plasma-cell proliferative disease with an expected 15 270 new cases and 11 070 deaths in the USA in 2004 alone. This accounts for 1% of all malignancies and slightly more than 10% of all hematologic malignancies in Caucasians and 20% in African Americans. The diagnosis is based on the presence of bone pain, anemia, and plasma-cell infiltrate in the bone marrow or within bone lesions. It is essential that the spectrum of plasma-cell proliferative disorders be recognized: monoclonal gammopathy of undetermined significance (MGUS), smoldering (asymptomatic) multiple myeloma (SMM), and active (symptomatic) MM. These distinctions affect important management decisions. Other related disorders include primary systemic amyloidosis, POEMS syndrome, and acquired Fanconi syndrome.
Mermithid Nematode Parasitism of Solenopsis Ants (Hymenoptera: Formicidae) of Northern Florida

Sexuals collected from nests of the fire ant, Solenopsis geminata (F.), the red imported fire ant, S. invicta Buren, and S. pergandei Forel in the Apalachicola National Forest were parasitized occasionally by a large mermithid nematode. Summer infection rates (1991–1993) varied by species and sex: 0% for S. invicta gynes, between 1 and 7% for S. pergandei gynes and males of all 3 species, and 16% for S. geminata gynes. The seasonality of infection coincided with the summer reproductive period of S. geminata and suggests the mermithid has an annual life cycle. The parasites, up to 15.5 cm in length, distend the abdomen of the host, but have little anatomical effect other than detracting from sex organ development. Mermithisized ants do not participate in mating flights and die when the parasites emerge. The mermithids emerge as sexually immature larvae, precluding their identification or taxonomic description. A mermithid this large has not been reported previously in Solenopsis . Currently, there is no record of mermithid parasitism in S. invicta and S. pergandei nor have mermithisized sexuals been reported in the genus.
Peripheral SMN restoration is essential for long-term rescue of a severe spinal muscular atrophy mouse model

Spinal muscular atrophy (SMA) is a motor neuron disease and the leading genetic cause of infant mortality; it results from loss-of-function mutations in the survival motor neuron 1 (SMN1) gene. Humans have a paralogue, SMN2, whose exon 7 is predominantly skipped, but the limited amount of functional, full-length SMN protein expressed from SMN2 cannot fully compensate for a lack of SMN1. SMN is important for the biogenesis of spliceosomal small nuclear ribonucleoprotein particles, but downstream splicing targets involved in pathogenesis remain elusive. There is no effective SMA treatment, but SMN restoration in spinal cord motor neurons is thought to be necessary and sufficient. Non-central nervous system (CNS) pathologies, including cardiovascular defects, were recently reported in severe SMA mouse models and patients, reflecting autonomic dysfunction or direct effects in cardiac tissues. Here we compared systemic versus CNS restoration of SMN in a severe mouse model. We used an antisense oligonucleotide (ASO), ASO-10-27, that effectively corrects SMN2 splicing and restores SMN expression in motor neurons after intracerebroventricular injection. Systemic administration of ASO-10-27 to neonates robustly rescued severe SMA mice, much more effectively than intracerebroventricular administration; subcutaneous injections extended the median lifespan by 25 fold. Furthermore, neonatal SMA mice had decreased hepatic Igfals expression, leading to a pronounced reduction in circulating insulin-like growth factor 1 (IGF1), and ASO-10-27 treatment restored IGF1 to normal levels. These results suggest that the liver is important in SMA pathogenesis, underscoring the importance of SMN in peripheral tissues, and demonstrate the efficacy of a promising drug candidate.
Gas-phase acidities of thiocarboxylic acids

Abstract The gas-phase acidity of thioacetic acid, determined using ion–molecule equilibrium reactions, was found to be ΔGacid = 329.0 ± 1.5 kcal mol−1. The gas-phase acidity of thiobenzoic acid was determined by ion–molecule bracketting reactions to be ΔGacid = 323 ± 5 kcal mol−1. Gas-phase acidities of these compounds, as well as of thioformic acid, were calculated; our calculations and experiments are in good agreement. The calculated value of the enthalpy of deprotonation of thioformic acid is consistent with previously published computational results.
Effect of elastic collisions on the frequency distribution of astrophysical maser radiation

Abstract The frequency distribution of astrophysical maser radiation is an importantingredient in analyzing the properties of astrophysical maser sources. The frequency profile of the absorption coefficient is studied analytically and computationally including the effect of elastic collisions. The evolution of the profile is detailedly discussed. Two important features that result from elastic collisions are: (1) The frequency profile of the absorption coefficient in the saturated regime becomes narrower and sharper. (2) Line narrowing continues during early saturation. These may help explain some observed narrow maser features.
Relative atomic transition probabilities for Na, Sc, Ti, Cr, Fe, Co, and Ni using flame atomic absorption spectroscopy

Abstract Relative atomic transition probabilities (Aji), for Na, Sc, Ti, Cr, Fe, Co, and Ni, using flame atomic absorption spectroscopy have been determined. Absorption measurements in air-acetylene and nitrous oxide-acetylene flames using both line emission and continuum excitation sources were employed. A comprehensive discussion and critical evaluation of Aji values for this work and others of comparable scope and design is included. The effect of the absorption line profile including hyperfine structure is discussed.
Stature and robusticity during the agricultural transition: evidence from the bioarchaeological record

The population explosion that followed the Neolithic revolution was initially explained by improved health experiences for agriculturalists. However, empirical studies of societies shifting subsistence from foraging to primary food production have found evidence for deteriorating health from an increase in infectious and dental disease and a rise in nutritional deficiencies. In Paleopathology at the Origins of Agriculture (Cohen and Armelagos, 1984), this trend towards declining health was observed for 19 of 21 societies undergoing the agricultural transformation. The counterintuitive increase in nutritional diseases resulted from seasonal hunger, reliance on single crops deficient in essential nutrients, crop blights, social inequalities, and trade. In this study, we examined the evidence of stature reduction in studies since 1984 to evaluate if the trend towards decreased health after agricultural transitions remains. The trend towards a decrease in adult height and a general reduction of overall health during times of subsistence change remains valid, with the majority of studies finding stature to decline as the reliance on agriculture increased. The impact of agriculture, accompanied by increasing population density and a rise in infectious disease, was observed to decrease stature in populations from across the entire globe and regardless of the temporal period during which agriculture was adopted, including Europe, Africa, the Middle East, Asia, South America, and North America.
EFFECTS OF THYROXIN INJECTIONS ON THE SUPRARENAL GLANDS OF THE MOUSE

The present investigation was undertaken to test the influence of an added amount of thyroid product on the histological structure of the mouse suprarenal. Beginning with the report of Magnus-Levy (1895), who first found that thyroid feeding may cause loss of weight in an animal, numerous papers have appeared recording an increase in body weight resulting from small dosage in thyroid feeding, and a decrease in body weight or a retardation in growth produced by higher dosages, the latter effect being possibly due, in the opinion of Hoskins (1916), to the toxic effect of the larger amounts. Besides changes in body weight, other effects that have been reported include: (a) Interference with pregnancy by thyroid of probably toxic size (Gudernatsch, 1915), an effect similar to that observed by Stockard (1913) in animals treated with alcohol; (b) hypertrophy of certain organs, including the suprarenals, following thyroxin injections (Cameron and Carmichael, 1921); and (c) sex differences in the response of the ...
ACCELERATION OF CHOLINE UPTAKE AFTER DEPOLARIZATION-INDUCED ACETYLCHOLINE RELEASE IN RAT CORTICAL SYNAPTOSOMES

— Activation of nerve elements in vivo and in vitro is associated with an increased rate of choline uptake by a Na+-dependent high affinity transport system. Following the methodology of Barker (1976), rat cortical synaptosomes were depolarized (37°C, 10min) by 25mM-KCl in the presence of CaCl2 (1 mM) or other divalent cations. After reisolation by centrifugation, the rate of 3H-choline uptake (1.25μM) was measured by Millipore filtration. KCl treatment alone failed to accelerate the rate of uptake in the reisolated synaptosomes. CaCl2, BaC12 or SrCl2 (but not MgCl2 or MnCl2) were necessary (1 mM) to observe the KCl induced acceleration. Moreover, RbCl, but not LiCl or CsCl, also produced the calcium-dependent rate enhancement in the reisolated synaptosomes. The conditions mediating the enhanced rate of choline uptake correlated strongly with those associated with neurotransmitter release. To test this possibility, synaptosomal acetylcholine content was measured in response to the various salt treatments. Treatment with KCI (25 mM) and CaCl2 (1 mM), but not KCl alone, reduced the synaptosomal acetylcholine content from 154 to 113pmol/mg protein. The respective rates of choline uptake increased about 60%. The increased rate was reversed by incubation with 50 μM-choline followed by synaptosome reisolation. This procedure also normalized the acetylcholine content. In summary, the rate of choline uptake by the high affinity choline uptake system is inversely related to the synaptosomal acetylcholine content.
A single injection of the kappa opioid antagonist norbinaltorphimine increases ethanol consumption in rats

Kappa opioid receptor (KOR) agonists interfere with the reinforcing effects of drugs of abuse. KOR agonists decrease heroin, cocaine, and ethanol self-administration, and block heroin and cocaine conditioned place preference (CPP) in rats. However, KOR agonists also produce emesis and dysphoria, making it difficult to determine if their effects on self-administration are due to an action on reward mechanisms or are secondary to the drug's direct aversive effects. Assuming that endogenous KOR ligands modulate circuits involved in drug and alcohol reward, selective KOR antagonists can be used to clarify these issues. If KOR antagonists increase drug self-administration then it is likely that endogenous KOR agonists directly modulate drug intake. To determine the effects of nor-BNI, the highly selective KOR antagonist, on ethanol consumption and CPP. Thirty-eight male Lewis rats were given free access to ethanol until stable self-administration was achieved. Animals were then administered a single injection of nor-BNI (10 mg kg−1) while ethanol intake was monitored. A single injection of nor-BNI induces a long-lasting increase in ethanol consumption, but does not induce a CPP. A high/low split revealed that this effect was primarily due to an increase in drinking in nor-BNI-treated high drinkers, which drank significantly more than saline-treated high drinkers and also drank significantly more when compared to their own pretreatment baseline. Blocking the KOR system increases ethanol self-administration, suggesting that the decrease in self-administration seen with KOR agonists is due to a direct modulation of reward circuitry.
Brevicomin: Principal Sex Attractant in the Frass of the Female Western Pine Beetle

The principal component of the sex attractant produced by the female western pine beetle (Dendrotonus brevicomis) is exo-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octane; the trivial name brevicomin is suggested.
Speech and Prosody Characteristics of Adolescents and Adults With High-Functioning Autism and Asperger Syndrome

Speech and prosody-voice profiles for 15 male speakers with High-Functioning Autism (HFA) and 15 male speakers with Asperger syndrome (AS) were compared to one another and to profiles for 53 typica...
Approximations Method for Space Frame Synthesis

A method is presented for the minimum mass design of three-dimensi onal space frames constructed of thinwalled rectangular cross-sectional members. Constraints on nodal displacements and rotations, material stress, local buckling, and cross-sectional dimensions are included. A high-quality separable approximate problem is formed in terms of the reciprocals of the four section properties of the frame element cross section, replacing all implicit functions with simplified explicit relations. The cross-sectional dimensions are efficiently calculated without using multilevel techniques. Several test problems are solved, demonstrating that a series of approximate problem solutions converge rapidly to an optimal design. HIS paper reports on a new approach and capability for the optimization of three-dimensi onal space frame type structures with nonstandardized element cross sections. The mass of the structure is to be minimized subject to constraints which include nodal displacements and rotations, material stress, local buckling, and design variable side constraints. The structure is represented by a finite element model using a twelve degree of freedom (two end nodes, with three displacements and three rotations per node) frame element. Figure 1 details the rectangular, thin-walled, doubly symmetric cross section for the /th element. A separable approximate problem is formed using reciprocal section properties (RSP's)—the inverse of an element's cross-sectional area and polar and bending moments of inertia (i.e., Xu = l/At; ** = !//,.; Xi3 = l/Izzi; Xi4 = \/Iyyi). These approximations are of high quality when formed in terms of the RSP's, due to the algebraic form of the actual problem statement. Side constraints on the cross-sectional dimensions (CSD's) are reflected into RSP space by means of an approximate relationship between these two sets of variables. The form of this approximate relationship is tailored to take advantage of the strengths of the selected optimizer. One of two optimizers may be selected to solve the approximate problem. The first is NEWSUMT, an extended quadratic interior penalty function optimizer.l The second is DUAL2, a dual space optimizer that maximizes the dual function by a second-order method.2 These problem solving capabilities are combined in a selfcontained Fortran code which allows the user to optimize a general three-dimensional space frame structure modeled with frame elements of thin-walled rectangular cross section. Several example problems are solved, showing that this new approach to the frame problem is useful and efficient.