cssi/SciSciGPT-SciSciNet huggingface dataset:
In situ friction and wear measurements of ion-implanted 304 stainless steel in nitrogen and oxygen ambients☆

Abstract The dual-ion implantation of titanium and carbon (4.6 × 1017 Ti ions cm-2 at 180 keV followed by 2.0 × 1017 C ions cm-2 at 50 keV) into 304 stainless steel was found to reduce friction and wear in vacuum, oxygen and air environments. Unlubricated friction measurements and wear track analyses were carried out in situ in a scanning Auger microprobe using a 440C pin at a hertzian contact stress 3 times the bulk yield strength of unimplanted 304 steel. In ultrahigh vacuum the friction coefficient was reduced from 1.2 to 0.6 – 0.8, while the wear track width decreased from 414 to 325 μm at 5000 cycles. In oxygen at a partial pressure of 2.1 × 10-5 Pa almost the same reductions in friction and wear were obtained as in air: ion implantation decreased the friction coefficient from 1.10 to 0.65 and the wear track width from 319 to 198 μm at 5000 cycles, compared with decreases of 1.0 to 0.5 and 255 to 190 μm respectively in air. Such decreases were not observed in nitrogen ambients, for which the results were similar to those in ultrahigh vacuum. Friction coefficients and the analyses of wear track compositions indicate that oxidation of the implanted layer during sliding reduces friction.
Robotic-assisted superficial temporal artery-to-middle cerebral artery anastomosis.

Robotic-assisted surgery is becoming more prevalent and accepted in the USA and is routine in many medical centers across a variety of specialties, but mainly in urology and general surgery. However, neurosurgery has yet to embrace this new technology. We used the da Vinci® robot (Intuitive Surgical, Sunnyvale, California) to perform a robotic-assisted superficial temporal artery-to-middle cerebral artery bypass on a cadaveric head. The object of this technical note is to describe the use of the da Vinci® robot to perform an extracranial–intracranial bypass. Using a cadaveric human head, the da Vinci® robot was successfully used to anastomose the superficial temporal artery to an M2 branch of the middle cerebral artery. We were successfully able to demonstrate the utility of using the da Vinci® robot in extracranial to intracranial anastomosis in a cadaveric head. The optics were excellent and physiologic tremor was eliminated. More studies are needed to assess the feasibility, safety, and utility of this device in living tissue within the field of neurosurgery.
Ecology and microbiology of biogasification

Abstract The biodegradation of organic matter to form methane and carbon dioxide requires the interactions of diverse populations of bacteria. The roles of each of these organisms in the process and how they interact with each other is understood only in a rudimentary way. This paper describes the investigation of the microbial ecology of the anaerobic degradation of biomass feedstocks.
EagleVision: A pervasive mobile device protection system

Mobile devices like laptops, iPhones and PDAs are highly susceptible to theft in public places like airport terminal, library and cafe. Moreover, the exposure of sensitive data stored in the mobile device could be more damaging than the loss of device itself. In this work, we propose and implement a pervasive mobile device protection system, named EagleVision, based on sensing and wireless networking technologies. Comparing with existing solutions, EagleVision is unique in providing an integrated protection to both device and data. It is a context-aware system which adjusts the protection level to the mobile device dynamically according to the context information such as the user proximity to the mobile device, which is collected via the interactions between the sensors carried by the user, embedded with the mobile device and deployed in the surrounding environment. Furthermore, it does not require explicit user intervention to utilize the system and hence avoid adding extra distractions to the user. Prototype implementation and extensive field test results demonstrate the effectiveness of EagleVision.
Scuffing of Area Contacts Under Starved Lubrication Conditions

The scuffing behavior of 390-T6 and DHT3 aluminum alloys, Si-Pb brass and gray cast iron, sliding against 1018 carburized steel, is experimentally studied under starved lubrication conditions. The major emphasis of the study is on the 390-T6 aluminum alloy. All tests are conducted in a high pressure tribometer (HPT) under RI34a (tetrafluoroethane) environment with polyalkylene glycol (PAG) and polyolester (POE) lubricants to simulate failures of critical tribocontacts in refrigerant compressors. An area contact, pin-on-disc geometry, is used to examine the effects of degree of lubricant starvation, sliding velocity, materials, and lubricant/refrigerant mixtures on scuffing. The scuffing transitions characteristics of 390-T6 aluminum as a function of lubricant supply rate are also examined. The processes leading to scuffing and failure mechanisms are studied by examination of scuffed surfaces and subsurfaces. Based on the experimental observations, it is hypothesized that bulk material failure during scuff...
Levels of allozyme diversity in populations of uncommon Neotropical tree species

The magnitude of allozyme variation within plant populations is influenced by ecological and life history characteristics of the species as well as recent population history (Brown 1979, Gottlieb 1981, Hamrick & Godt 1989, Hamrick et al. 1979, Loveless & Hamrick 1984). For instance, populations that have been small for several generations or have experienced a series of recent bottlenecks should have less genetic variation than populations that have been large and stable for several generations (Karron 1987, Karron et al. 1988, Nei et al. 1975). Tropical forests are characterized by high species diversity and low population numbers for the majority of the community's species (Black et al. 1950, Fedorov 1966). Yet, in most tropical tree communities there are several species with high population numbers. Thus, it is possible to compare levels of genetic diversity between common and uncommon tree species belonging to the same community. The distribution of allozyme variation in 16 common woody species (more than four individuals per hectare) has been described for the moist tropical forest of Barro Colorado Island, Republic of Panama (Hamrick & Loveless 1989, Loveless & Hamrick 1987). Levels of genetic diversity maintained within populations of these 16 species of trees and shrubs varied greatly among species but, on average, was high relative to that for all plant species or to temperate woody species (Hamrick & Godt 1989, Hamrick & Loveless 1989). Hamrick & Loveless (1989) could, however, find no relationship between population density and allozyme diversity. In this paper we measure the allozyme diversity within populations of 16 uncommon species from the mature forest community of Barro Colorado Island (BCI). We compare the results from this analysis to those of the earlier analyses (Hamrick & Loveless 1989, Loveless & Hamrick 1987) to determine whether species with small population sizes on BCI have significantly less allozyme diversity than more common species from this site.
Enzyme‐catalyzed synthesis of structured phospholipids with conjugated linoleic acid

Structured phospholipids were synthesized with the functional lipid conjugated linoleic acid (CLA). The lipase- and phospholipase A 2 -catalyzed enzymatic acidolysis reaction between phospholipids (PL) and CLA was used for fatty acid modification. Enzymatic processes were an effective way to produce structured PL. Screening of four lipases and immobilized phospholipase A 2 and a combination of lipase and phospholipase showed that only Lipozyme RM IM and Lipozyme TL IM were effective in incorporation of CLA into PL. The maximum incorporation achieved by the latter enzyme was 16% with soy PL in 72 h.
Multi-player non-zero-sum games: Online adaptive learning solution of coupled Hamilton-Jacobi equations

In this paper we present an online adaptive control algorithm based on policy iteration reinforcement learning techniques to solve the continuous-time (CT) multi player non-zero-sum (NZS) game with infinite horizon for linear and nonlinear systems. NZS games allow for players to have a cooperative team component and an individual selfish component of strategy. The adaptive algorithm learns online the solution of coupled Riccati equations and coupled Hamilton-Jacobi equations for linear and nonlinear systems respectively. This adaptive control method finds in real-time approximations of the optimal value and the NZS Nash-equilibrium, while also guaranteeing closed-loop stability. The optimal-adaptive algorithm is implemented as a separate actor/critic parametric network approximator structure for every player, and involves simultaneous continuous-time adaptation of the actor/critic networks. A persistence of excitation condition is shown to guarantee convergence of every critic to the actual optimal value function for that player. A detailed mathematical analysis is done for 2-player NZS games. Novel tuning algorithms are given for the actor/critic networks. The convergence to the Nash equilibrium is proven and stability of the system is also guaranteed. This provides optimal adaptive control solutions for both non-zero-sum games and their special case, the zero-sum games. Simulation examples show the effectiveness of the new algorithm.
Flexural motion of a radially rotating beam attached to a rigid body

Flexural motion of a radially rotating beam attached to a rigid body is investigated. Fully coupled non-linear equations of motion are derived by using the extended Hamilton's Principle. Spatial dependence is suppressed by using the extended Galerkin method. A torque profile is used to drive the rotating body so that the rigid body motion is not known a priori . The effect of the coupling terms upon the vibration waveforms are investigated by using both a linearized analysis and numerical solution of the differential equations. It is found that for small values of the ratio of the flexible beam and rigid shaft inertia uncoupled equations can lead to substantially incorrect results, particularly with regard to frequencies.
A Model of Transient Heat and Mass Transfer in a Heterogeneous Medium of Cerium Dioxide Undergoing Nonstoichiometric Reduction

The redox chemistry of nonstoichiometric metal oxides can be used to produce chemical fuels by harnessing concentrated solar energy to split water and/or carbon dioxide. In such a process, it is desirable to use a porous reactive substrate for increased surface area and improved gas transport. The present study develops a macroscopic-scale model of porous ceria undergoing thermal reduction. The model captures the coupled interactions between the heat and mass transfer and the heterogeneous chemistry using a local thermal non-equilibrium (LTNE) formulation of the volume averaged conservation of mass and energy equations in an axisymmetric cylindrical domain. The results of a representative test case simulation demonstrate strong coupling between gas phase mass transfer and the chemical kinetics as well as the pronounced impact of optical thickness on the temperature distribution and thus global solar-to-chemical energy conversion.© 2012 ASME
Aharonov-Bohm scattering amplitude.

The two principal approaches to the quantum-mechanical calculation of scattering by flux tubes in two spatial dimensions are reviewed and corrections made where needed. It is noted that even when appropriate care is taken the standard phase-shift method fails to agree with the (corrected) Aharonov-Bohm result. The discrepancy is resolved by noting that the former approach requires an improper interchange of a limit and a summation. That interchange is justified only when the phase shifts go to zero sufficiently rapidly as the angular momentum becomes arbitrarily large, a condition which fails to hold in this particular scattering problem.
Profile etching for prefiguring X-ray mirrors.

A method to pre-shape mirror substrates through etching with a broad-beam ion source and a contoured mask is presented. A 100 mm-long elliptical cylinder substrate was obtained from a super-polished flat Si substrate with a 48 nm root-mean-square (r.m.s.) figure error and a 1.5 A r.m.s. roughness after one profile-etching process at a beam voltage of 600 V without iteration. A follow-up profile coating can be used to achieve a final mirror. Profile etching and profile coating combined provide an economic way to make X-ray optics, such as nested Kirkpatrick-Baez mirrors.
MAPK/AP-1 activation mediates TLR2 agonist-induced SPLUNC1 expression in human lung epithelial cells.

Abstract Background Short Palate Lung and Nasal epithelium Clone 1 (SPLUNC1) is a newly described host defense protein, primarily expressed in large airway epithelial cells. Reduced SPLUNC1 has been reported in allergic and cigarette smoke-exposed airways. We found that Mycoplasma pneumoniae increases SPLUNC1 in airway epithelium in part via activating TLR2-NF-κB pathway. However, the contribution of additional signaling pathways to TLR2-mediated SPLUNC1 expression remains unclear. In the present study, we investigated if TLR2-induced mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) signaling regulates SPLUNC1 expression in human lung epithelial cells. Methods Human lung epithelial NCI-H292 cells were stimulated with a TLR2 agonist Palmitoyl (3)-Cys-Ser-Lys (4)-OH (Pam 3 CSK 4 ). MAPK/AP-1 activation and its role in SPLUNC1 regulation were investigated by Western blot, c-Jun activation assay, chromatin immunoprecipitation (ChIP) and real-time PCR. SPLUNC1 promoter activity was assessed by a luciferase reporter assay. Results Pam 3 CSK 4 increased SPLUNC1 expression in NCI-H292 cells in a dose- and time-dependent manner, and enhanced SPLUNC1 promoter activity. Pam 3 CSK 4 -treated cells demonstrated activated MAPK and c-Jun compared to untreated cells. ChIP assay indicated increased c-Jun binding to the SPLUNC1 promoter following Pam 3 CSK 4 stimulation. Inhibition of ERK1/2 significantly reduced Pam 3 CSK 4 -mediated c-Jun activation and SPLUNC1 expression. Conclusions Our results for the first time demonstrate that TLR2-mediated MAPK/AP-1 activation up-regulates lung epithelial SPLUNC1 expression at the transcriptional level. Understanding SPLUNC1 gene regulation should provide more specific therapeutic targets to restore deficient SPLUNC1 production in diseased airways.
Sinus histiocytosis with massive lymphadenopathy. Report of a case associated with elevated EBV antibody titers

A case of sinus histiocytosis with massive lymphadenopathy is reported in which the patient had higher than expected antibody titers against the Epstein-Barr (EBV) and rubella viruses. In addition, high anti-EBV titers in family members physically separated suggest an altered immunologic reactivity which could be important in the development of the massive lymphadenopathy associated with this syndrome. The relationship of this syndrome to the EBV along with its histologic characteristics suggest that it may represent a peculiar, late sequelae of infection with this virus, or an atypical manifestations of infectious mononucleosis in an immunologically defective individual.
Soybean response to preplant and foliar-applied potassium chloride with strobilurin fungicides.

Potassium chloride (KCl) preplant or foliar applied with fungicides to soybean [Glycine max (L.) Merr.] may allow farmers to increase yields when soil K availability is reduced and/or when Septoria brown spot (SBS) (Septoria glycines), frogeye leaf spot (FLS) (Cercospora sojina), or sudden death syndrome (SDS) (Fusarium solani (Mart.) Sacc. f. sp.glycines) are present. Interactions between fertilizer and fungicide management programs have not been examined in the central United States. Our objective was to evaluate the effect of preplant- and foliar-applied KCl alone or combined with pyraclostrobin, azoxystrobin, or azoxystrobin plus lambda-cyhalothrin on soybean response and severity of SBS, FLS, and SDS. Experiments were conducted in northeastern (Novelty) and southeastern (Qulin) Missouri in 2006 and 2007 on soils with low to medium K. Leaf K concentrations increased 1.4 to 6.1 g kg -1 following preplant KCI compared to nontreated or foliar KCl. Leaf Cl concentrations increased significantly with preplant KCl at Qulin and foliar KCI at R4 at Qulin and Novelty. At Novelty, preplant KCI reduced the severity of SBS and FLS up to 6%, and increased yield 340 kg ha -1 , while foliar KCl increased yield 110 kg ha -1 An R4 application of strobilurin fungicides increased yields 230 to 360 kg ha -1 at Novelty. At Qulin, soybean yield increased 390 kg ha -1 with preplant KCI, while there were variable effects of fungicides on the severity of SBS, FLS, or SDS, and no yield increase due to fungicides or foliar KCl. Foliar applications ofKCl were no substitute for preplant KCl.
Alternatively Spliced RAGEv1 Inhibits Tumorigenesis through Suppression of JNK Signaling

Receptor for advanced glycation end products (RAGE) and its ligands are overexpressed in multiple cancers. RAGE has been implicated in tumorigenesis and metastasis, but little is known of the mechanisms involved. In this study, we define a specific functional role for an alternate splice variant termed RAGE splice variant 1 (RAGEv1), which encodes a soluble endogenous form of the receptor that inhibits tumorigenesis. RAGEv1 was downregulated in lung, prostate, and brain tumors relative to control matched tissues. Overexpressing RAGEv1 in tumor cells altered RAGE ligand stimulation of several novel classes of genes that are critical in tumorigenesis and metastasis. Additionally, RAGEv1 inhibited tumor formation, cell invasion, and angiogenesis induced by RAGE ligand signaling. Analysis of signal transduction pathways underlying these effects revealed marked suppression of c-jun-NH(2)-kinase (JNK) pathway signaling, and JNK inhibition suppressed signaling through the RAGE pathway. Tumors expressing RAGEv1 were significantly smaller than wild-type tumors and displayed prominently reduced activation of JNK. Our results identify RAGEv1 as a novel suppressor, the study of which may offer new cancer therapeutic directions.
High-field NMR studies of molecular recognition and structure-function relationships in antimicrobial piscidins at the water-lipid bilayer interface.

High magnetic field solid-state NMR was performed on amphipathic cationic antimicrobial peptides from fish to characterize their secondary structure and orientation in hydrated phospholipid bilayers. High-resolution distance and orientational restraints on 13C- and 15N-labeled amidated piscidins 1 and 3 provided site-specific information establishing α-helicity and an orientation parallel to the membrane surface. Few membrane-bound natural peptides with this topology have been structurally studied at high resolution in the presence of hydrated lipid bilayers. This orientation was foreseen since the partitioning of amphipathic cationic antimicrobial peptides at the water−bilayer interface allows for favorable peptide−lipid interactions, and it may be related to the mechanism of action. The enhanced resolution obtained at 900 MHz evidences a determinant advantage of ultra-high-field NMR for the structural determination of multiple-labeled peptides and proteins.
Virtual Reality hardware for use in interactive 3D data fusion and visualization

Virtual reality has become a tool for use in many areas of research. We have designed and built a VR system for use in range data fusion and visualization. One major VR tool is the CAVE. This is the ultimate visualization tool, but comes with a large price tag. Our design uses a unique CAVE whose graphics are powered by a desktop computer instead of a larger rack machine making it much less costly. The system consists of a screen eight feet tall by twenty-seven feet wide giving a variable field-of-view currently set at 160 degrees. A silicon graphics Indigo2 MaxImpact with the impact channel option is used for display. This gives the capability to drive three projectors at a resolution of 640 by 480 for use in displaying the virtual environment and one 640 by 480 display for a user control interface. This machine is also the first desktop package which has built-in hardware texture mapping. This feature allows us to quickly fuse the range and intensity data and other multi-sensory data. The final goal is a complete 3D texture mapped model of the environment. A dataglove, magnetic tracker, and spaceball are to be used for manipulation of the data and navigation through the virtual environment. This system gives several users the ability to interactively create 3D models from multiple range images.
Lateralized interference in finger tapping: Assessment of block design activities☆

Abstract Dual task procedures were used to evaluate lateralized processing of block design solutions. Right-handed college students tapped a micro-key alone vs tapped while solving block design problems. Lateralized interference, implicating right-hemisphere processing, was observed when subjects manually completed block designs with their non-tapping hand. When manual block manipulation was not required and subjects solved designs mentally, a different laterality pattern suggesting left-hand facilitation in conjunction with right-hand interference in tapping performance was observed. Only the facilitation effect, however, was reliably different from zero.
Stability and implementation of partitioned CSI solution procedures

A partitioned procedure developed for the efficient solution of control-structure interaction (CSI) problems is presented with emphasis on its computational stability, implementation aspects, and accuracy characteristics. The partitioned CSI procedure proposed here can facilitate the use of large-scale structural analysis for control-structure interaction problems. It is anticipated that real-time CSI simulations will become routine if adequate advances are made in the construction of reduced-order observers and, for some time variant problems, if substantially faster parallel solution procedures for the Riccati equations become available.
Binocular Performance And Design

A binocular extends the range of human vision. Binoculars enable the user to see objects at greater distances or, alternatively, to see greater detail in distant objects. In failing light, binocul are used to detect objects that the naked eye cannot detect. Binoculars also extend the range of stereo vision of the user; this application is primarily of interest in military fire control.
Leader-Determined Membership Protocol

Many fault-tolerant systems organize the replicas of an application process as a process group. The Leader-Determined Membership Protocol determines a new membership for the process group, when a member becomes faulty, a member leaves the group, or a new member joins the group. If the primary becomes faulty, the protocol selects a new primary deterministically, based on the precedences and the ranks of the backups. The new primary determines which processes are members of the new membership, and communicates that information to the backups. The protocol maintains a consistent view of the membership, so that the members see the same primary, the same set of members, and the same primary view number. It also ensures consistency of the states of the members, and consistency with other processes with which the members communicate. By avoiding the use of a multiple-round majority-based consensus algorithm, the Leader-Determined Membership Protocol achieves better performance than other membership protocols, and can operate with the primary and only a single backup.
Role of nitric oxide pathway in placental dysfunction following fetal bypass.

Background. The etiology of placental dysfunction after fetal cardiopulmonary bypass remains unknown. The placental nitric oxide (NO) pathway has been implicated in this pathophysiology. We set out to examine possible perturbations in this pathway in an ovine model of fetal bypass. Methods. Ovine fetuses (n 14) between 100 and 114 days of gestation, instrumented to measure hemodynamics and umbilical blood flow, were placed on bypass for 30 minutes and followed after bypass for 2 hours. Sham controls (n 6) were instrumented but did not undergo bypass. Real-time, in-vivo NO concentrations were measured in the placental circulation. To examine other components of the NO pathway, fetal plasma samples were analyzed by immunoassays for total NO metabolite and cyclic guanosine 3=,5=‐cyclic monophosphate (cGMP) levels. In addition, the expression of phosphodiesterase-5 was examined in placenta by immunohistochemistry. Statistical analysis was performed using analysis of variance with least significant difference post hoc tests (p < 0.05). Results. With the onset of bypass, an immediate increase occurs in umbilical NO concentrations. These return to baseline with cessation of bypass, and decline thereafter. In contrast, there was a linear increase in fetal plasma cGMP levels and a decline in NO metabolite concentrations through the post-bypass period. There was a dramatic increase in placental phosphodiesterase-5 expression with 30 minutes of bypass. The changes occur simultaneously with decreasing umbilical flows, increased placental vascular resistance, and worsening placental gas exchange. Conclusions. Fetal bypass leads to significant reductions in placental NO concentrations despite increases in fetal plasma cGMP and placental phosphodiesterase-5 levels, indicative of perturbations in the fetal-placental NO pathway. (Ann Thorac Surg 2007;84:917‐25) © 2007 by The Society of Thoracic Surgeons
Finite-size effects in conductance measurements on quantum dots.

The observation of the Kondo effect in quantum dots has provided new opportunites to finally observe the controversial Kondo screening cloud. Here we study the conductance of a quantum dot embedded in a finite length quantum wire, predicting a change in behavior when the length of the wire is comparable to the size of the screening cloud.
Embedded software debugging using virtual filesystem abstractions

We present a scalable technique to simplify the software debugging process for embedded systems that is based on the use of distributed filesystem abstractions. In this technique, the principal building blocks within embedded systems comprising ''system-on-chip'' (SoC) devices export debugging interfaces realized with filesystem abstractions. These filesystem interfaces are composed in a manner consistent with the hardware hierarchy and provide a portable interface to concurrently debug software executing in the various processing elements within the embedded system. We illustrate application of the model to support the various software debugging requirements unique to SoCs, many of which traditional methods are ill-equipped to deal with. We also present an architecture that may be used to realize distributed filesystem abstractions within resource constrained embedded architectures.
Opening Pathways for Underrepresented High School Students to Biomedical Research Careers: The Emory University RISE Program

Increasing the college graduation rates of underrepresented minority students in science disciplines is essential to attain a diverse workforce for the 21st century. The Research Internship and Science Education (RISE) program attempts to motivate and prepare students from the Atlanta Public School system, where underrepresented minority (URM) students comprise a majority of the population, for biomedical science careers by offering the opportunity to participate in an original research project. Students work in a research laboratory from the summer of their sophomore year until graduation, mentored by undergraduate and graduate students and postdoctoral fellows (postdocs). In addition, they receive instruction in college-level biology, scholastic assessment test (SAT) preparation classes, and help with the college application process. During the last 4 yr, RISE students have succeeded in the identification and characterization of a series of proteins involved in the regulation of nuclear organization and transcription. All but 1 of 39 RISE students have continued on to 4-year college undergraduate studies and 61% of those students are currently enrolled in science-related majors. These results suggest that the use of research-based experiences at the high school level may contribute to the increased recruitment of underrepresented students into science-related careers.
Hybrid spectrin type repeats produced by exon-skipping in dystrophin

Abstract Dystrophin is the protein whose defect underlies Duchenne Muscular Dystrophy, DMD, a common (1:3500 male births) and fatal condition in which muscle tissue deteriorates leading to death in the second or third decade of life. Dystrophin is coded for by the largest human gene, and one of the most complex. It is translated from at least 7 distinct promoters, with the largest transcripts (which are the ones involved in DMD) containing 79 exons over > 2.5 Mbp [K.F. O'Brien, L.M. Kunkel, Dystrophin and muscular dystrophy: past, present, and future, Mol. Genet. Metab. 74 (2001) 75–88, H.M. Sadoulet-Puccio, L.M. Kunkel, Dystrophin and its isoforms, Brain Pathol. 6 (1996) 25–35]. Exacerbating this complexity, it has recently been shown that dystrophin is subject to extensive alternative RNA processing, potentially producing a wide variety dystrophin variants [M. Sironi, R. Cagliani, U. Pozzoli, A. Bardoni, G.P. Comi, R. Giorda, N. Bresolin, The dystrophin gene is alternatively spliced throughout its coding sequence FEBS Lett 517 (2002) 163–166]. The structure of the dystrophin protein is highly modular, with the most common module being a motif termed the spectrin type repeat, or STR, of which there are 24. Each STR is roughly coded for by two exons, and the most common type of multiple exon-skipping events start and end at introns in the middle of STRs [R.G. Roberts, A.J. Coffey, M. Bobrow, D.R. Bentley, Exon structure of the human dystrophin gene Genomics 16 (1993) 536–538, M. Koenig, L.M. Kunkel, Detailed analysis of the repeat domain of dystrophin reveals four potential hinge segments that may confer flexibility, J. Biol. Chem. 265 (1990) 4560–4566]. This would produce fractional STR modules, however, the concept of STRs as proteins domains makes the viability of such fractional motifs questionable. However, certain of these events produce pairs of potentially complementary fractional domain that might reassemble into a hybrid STR motif. We have constructed model fragment corresponding to one such exon-skipping event, and show that the hybrid STR so produced is viable, and furthermore that some of the properties of the protein containing it differ substantially of the native, un-skipped parent.
Expression of genes of the T-cell antigen receptor complex in precursor thymocytes

The antigen receptor on Tlymphocytes has recently been characterized as a heterodimeric, transmembrane glycoprotein consisting of disulphide-linkedα(acidic) and β (basic) subunits of relative molecular mass (Mr) 40,000–45,000 each. The genes encoding these proteins have been cloned1–4 and shown to resemble immunoglobulin genes in both overall structure and the requirement for DNA rearrangement before expression5–11. In humans, three additional proteins, termed the T3 complex, are found associated with the clonotypic receptor, and a role for T3 in receptor expression has been proposed12–15. Despite these recent advances in characterizing the antigen receptor complex, there is as yet little understanding of T-cell maturation, particularly the stage of T-cell ontogeny at which the genes encoding the antigen receptor and its associated structures are expressed and assembled. In the adult, stem cells destined to differentiate into T cells arise in the bone marrow and migrate to the thymus16, where T-cell precursors proliferate, develop a preference for recognizing antigens in the context of self MHC molecules17,18and are released to the periphery. Recently, cells that have the properties of immature murine thymocytes have been isolated and described19,20. We have now analysed these cells with a series of molecular probes and we describe three distinct patterns of T-cell antigen receptor gene rearrangements in developing thymocytes.
Moral Imagination, Trading Zones, and the Role of the Ethicist in Nanotechnology

The societal and ethical impacts of emerging technological and business systems cannot entirely be foreseen; therefore, management of these innovations will require at least some ethicists to work closely with researchers. This is particularly critical in the development of new systems because the maximum degrees of freedom for changing technological direction occurs at or just after the point of breakthrough; that is also the point where the long-term implications are hardest to visualize. Recent work on shared expertise in Science & Technology Studies (STS) can help create productive collaborations among scientists, engineers, ethicists and other stakeholders as these new systems are designed and implemented. But collaboration across these disciplines will be successful only if scientists, engineers, and ethicists can communicate meaningfully with each other. The establishment of a trading zone coupled with moral imagination present one method for such collaborative communication.
The Thermodynamic Properties of Silicon Oxynitride

A critical assessment of thermal and equilibrium data for silicon oxynitride (Si2N2O) is presented. Selected values for the heat of formation of Si2N2O from the elements and the absolute entropy of Si2N2O at 298.15 K are ΔH0f,298=−947.7 ± 5.4 kJ/mol and S0298= 45.35 ± 0.4 J/mol·K, respectively. A table of thermodynamic functions for Si2N2Ofrom 298 to 2500 K, which has been calculated from the analysis of the literature data, is also presented.
Modeling of aerial-to-aerial short-distance free-space optical links

Increased RF noise floor, crowded and scarce wireless spectrum, and security are issues challenging present-day aerial wireless communication. Optical wireless (or free-space optical (FSO)) is an alternative communication system applicable to air-to-air (A2A) or air-to-ground (A2G) applications. An FSO link is able to provide high bandwidth, low-power, and secure communication for various unmanned aerial systems (UASs) and ground nodes, including mobile and fixed stations. However, unlike RF, optical communication is highly sensitive to misalignment and platform instability that causes unavoidable communication interruptions. Developing aerial optical wireless communication systems requires modeling the effects of UAS instability on the FSO system performance, including FSO link throughput. This work aims to develop a rigid and simple modeling framework for A2A FSO communication links. The framework is abstract, general, and platform-independent. The model relates instability to averaged percentage alignment (APA), which can be used to predict throughput and other performance-related parameters. A planer arrays of optical transmitters and receivers is used and proposed as a promising technology for FSO communication with large field-of-view and diversity-ready performance. Also, a novel alignment model using geometric intersection is developed and analyzed against simulated and real multi-rotor platforms.
POSITIVSTELLENSATZ CERTIFICATES FOR NON-FEASIBILITY OF CONNECTIVITY GRAPHS IN MULTI-AGENT COORDINATION

Abstract In this paper, we discuss how to obtain certificates for the non-feasibility of connectivity graphs arising from multi-agent formations. We summarize some previous work on connectivity graphs and their feasibility. Next, we introduce the Positivstellensatz to show how it can be used to better understand the space of all connectivity graphs for a fixed number of vertices, which had previously been understood as only a subspace of the space of all graphs. We study one particular class of graphs and use our methodology to prove some more results in the feasibility of connectivity graphs.
Abstract PR11: Hematopoietic system aging has profound effects on the breast tumor microenvironment and cancer progression

The majority of breast neoplasms are diagnosed in patients who are between the ages of 65 and 80. Although tumor growth is generally less aggressive and metastasis is less prevalent in older patients than in younger patients, elderly patients suffer the highest mortality and morbidity associated with breast cancer and breast cancer treatment. The reasons for age-dependent differences in incidence and aggressiveness of breast cancer are not understood. Treatment of breast cancer patients therefore presents age-specific challenges. We recently established mouse and human xenograft breast tumor models that mimic the age dependent disease progression that is observed in breast cancer patients, whereby tumor cells implanted into aged mice had lower incidence and slower growth kinetics than when implanted into young mice. Moreover, alpha-smooth muscle actin-positive myofibroblasts within the tumor microenvironment were significantly less prevalent in the tumors from aged mice than in size-matched tumors from young mice. We discovered that bone marrow derived cells from aged mice were significantly less effective in supporting breast cancer progression than the counterpart cells from young mice. Strikingly, bone marrow derived cells from young mice rescued tumor growth and stromal desmoplasia in aged mice. We are elucidating some of the molecular and phenotypic differences between young and aged tumor-promoting bone marrow cells. For example, we found that bone marrow cells from aged mice express lower levels of the cytokine, granulin, which is known to activate normal mammary fibroblasts in young mice. Our findings indicate that the age of the host hematopoietic system is a powerful determinant of breast tumor progression. Defining functional and molecular differences between tumor supportive hematopoietic cells in young and aged hosts should lay a foundation for further work in this relatively uncharted area of cancer research. Understanding tumor support mechanisms that exist in young and aged hosts should suggest new ideas for preclinical development of age-stratified breast cancer therapies. Citation Format: Timothy Marsh, Irene Wong, Amey Barakat, Yuanbo Qin, Sandra S. McAllister. Hematopoietic system aging has profound effects on the breast tumor microenvironment and cancer progression. [abstract]. In: Abstracts: AACR Special Conference on Cellular Heterogeneity in the Tumor Microenvironment; 2014 Feb 26-Mar 1; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(1 Suppl):Abstract nr PR11. doi:10.1158/1538-7445.CHTME14-PR11
Electrically controllable ionic polymeric gels as adaptive optical lenses

Reversible change in optical properties of ionic polymeric gels, 2-acrylamido-2-methylpropane sulfonic acid (PAMPS) and polyacrylic acid plus sodium acrylate cross-linked with bisacrylamide (PAAM), under the effect of an electric field is reported. The shape of a cylindrical piece of the gel, with flat top and bottom surfaces, changed when affected by an electric field. The top surface became curved and the sense of the curvature (whether concave or convex) depended on the polarity of the applied electric field. The curvature of the surface changed from concave to convex and vice versa by changing the polarity of the electric field. By the use of an optical apparatus, focusing capability of the curved surface was verified and the focal length of the deformed gel was measured. The effect of the intensity of the applied electric field on the surface curvature and thus, on the focal length of the gel are tested. Different mechanisms are discussed; either of them or their combination may explain the surface deformation and curvature. Practical difficulties in the test procedure and the future potential of the electrically adaptive and active optical lenses are also discussed. These adaptive lenses may be considered as smart adaptive lenses for contact lens or other optical applications requiring focal point undulation.
Fiber-based polarization-sensitive spectral domain optical coherence tomography using a fiber optic spectral polarimetry instrument

We present a novel fiber-based polarization sensitive spectral domain optical coherence tomography (SD-OCT) system using a fiber optic spectral polarimetry instrument (FOSPI), which provides measurement of depth-resolved polarization state of backscattered light from a specimen with single optical frequency scanning. By inserting a FOSPI in the detection path of SD-OCT, the full set of Stokes parameters of light backscattered at the specific depth of a specimen can be obtained without any other polarization controlling components in the system and the prior knowledge of the polarization state of the light incident on the sample. The operation principle of the fiber-based polarization sensitive spectral domain optical coherence tomography is demonstrated with a Mica plate as birefringent sample.
Superfluidity in neutron stars

Abstract Arguments are presented to show that the BCS theory of superfluidity in its original form may not be applicable to neutron star matter over a wide range of density.
Tree-rings and history in the western United States

The annual rings in suitable living trees have provided significant, centuries-long histories of past rainfall, temperature and river flow for many regions and have served to precisely date several hundred Southwestern ruins by overlap-matching with ancient timbers. Some of the stunted trees in very adverse environments were found to have the most sensitive chronologies and to attain ages twice or more the usual maxima on optimum sites. Tree-ring data for the western United States show that in pre-Columbian times the accumulated excess or deficit in rainfall occasionally greatly exceeded that recorded by gages during the past decades.
Street lamps, alleys, ratio analysis, and nonprofit organizations

This article offers an accounting-based framework for evaluating the efficiency of nonprofit organizations using four factors. Separately, these factors reflect (1) the proportion of revenues actually used in the current year, (2) the proportion of the expenditures allocated to programs, (3) the units of output produced from that spending, and (4) the value of the units produced, expressed in terms of an index value. Combined, these four factors measure the value of units produced per dollar of revenue received, an accounting measure of overall efficiency. Using this framework provides insight into both the appropriateness and the limitations of employing solely financial measures to judge nonprofit organizations and also identifies conceptual areas absent from currently available evaluation tools.
Utilization of actively-induced, prompt radiation emission for nonproliferation applications

Abstract The pulsed photonuclear assessment (PPA) technique, which has demonstrated the ability to detect shielded nuclear material, is based on utilizing delayed neutrons and photons between accelerator pulses. While most active interrogation systems have focused on delayed neutron and gamma-ray signatures, there is an increasing need to bring faster detection and acquisition capabilities to field inspection applications. This push for decreased interrogation times, increased sensitivity, and mitigation of false positives requires that detection systems take advantage of all available information. Collaborative research between Idaho National Lab (INL), Idaho State University’s Idaho Accelerator Center (IAC), Los Alamos National Laboratory (LANL), and Oak Ridge National Laboratory (ORNL), has focused on exploiting actively-induced, prompt radiation signatures from nuclear material within a pulsed photonuclear environment. To date, these prompt emissions have not been effectively exploited due to difficulties in detection and signal processing inherent in the prompt regime as well as an overall poor understanding of the magnitude and yields of these emissions. Exploitation of prompt radiation (defined as during an accelerator pulse/photofission event and/or immediately after (
New Channel Access Coordination Functions in Large Scale Wireless LAN Systems

Large-scale wireless LAN systems based on the IEEE 802.11 standards have become the most successful wireless networks deployed in large organizations, such as educational campuses and corporate warehouses. However, the suite of IEEE 802.11 MAC protocols, including DCF, PCF and EDCA mechanisms, was unable to meet the challenges to provide collision freedom and differentiated quality of services. We propose a channel access scheduling protocol based on Latin squares, called DCLASS (Distributed Coordination based on Latin SquareS), that provisions a set of highly desirable features to large scale wireless networks with stringent performance demands. DCLASS is scalable, fair, and co-exists with IEEE 802.11 nodes with traditional DCF mechanisms. The performance of DCLASS is evaluated using an IEEE standards compliant simulation toolkit, QualNet 4.5, in distributed WLAN systems. The experiment results show the near-optimum performance of DCLASS in contrast to IEEE 802.11 DCF under various scenarios.
Short-Term Effects of Wastewater Land Application on Soil Chemical Properties

Land application of wastewater has been accepted as an effective wastewater treatment method and disposal option in semiarid and arid areas in the world. Although it has economical, environmental, and social benefits, it is sometimes questioned as an environmentally sound method. Water mass balance method has proved to be an effective approach to designing a wastewater land application system to remove nitrogen at the municipal wastewater treatment plant at the City of Littlefield, Texas, USA. The study in this paper was to evaluate the short-term effects of wastewater land application on soil chemical properties at the same site from 16 June 2006 to 28 June 2007 with the system designed by the water mass balance method. Soil samples were taken at the start and at the end of this study at different depths from soil surface down to 91 cm at the research site (54 × 18 m), and analyzed for pH, total Kjeldahl nitrogen, nitrate–nitrogen, ammonia–nitrogen, electrical conductivity, calcium, magnesium, sodium, and sodium adsorption ratio. The results showed that there was no negative change of those soil chemical properties during the research period in this wastewater land application system designed by water mass balance method.
Graph Processing on an "almost" Relational Database

It would be hard to disagree with the contention that graph processing (whether it be of connections between people, shopping habits,...) allows the creation of valuable data-driven products and insights. There is less consensus on the systems that make it easy to analyze these graphs. In this paper, we argue that a relational database (actually, a close approximation to one) is well suited for many graph processing applications. We restrict our claims to the following case, which, we believe, dominates the nature of much data analyses --- the data does not change during the analysis in response to external events. We present representative examples from our work at LinkedIn, the world's largest professional network. We present performance results for these examples using Q, a single-node, analytical database.