cssi/SciSciGPT-SciSciNet huggingface dataset:
Some autocorrelation properties of phase-coded waveforms

In this paper we study some autocorrelation properties of a train of identical signals overlaid with a phase coding. Prior publications have investigated this problem under the assumption that, for the purpose of the phase coding, the original (uncoded) signal forming the train is divided into a number of bits that are either all identical or all distinct. This paper extends the discussion to the case of repeated bits. We derive and analyze sufficient conditions for cancelation of the waveform's autocorrelation sidelobes located around the main lobe area.
ZAMBEZI: a parallel pattern parallel fault sequential circuit fault simulator

Sequential circuit fault simulators use the multiple bits in a computer data word to accelerate simulation. We introduce, and implement, a new sequential circuit fault simulator, a parallel pattern parallel fault simulator, ZAMBEZI, which simultaneously simulates multiple faults with multiple vectors in one data word. ZAMBEZI is developed by enhancing the control flow, of existing parallel pattern algorithms. For a very wide range of benchmark circuits, compared to parallel fault and parallel pattern simulators, ZAMBEZI offers either the best, or very close to the best, uniprocessor performance. ZAMBEZI also offers superior performance when parallelized.
Performance Characteristics of Scaled Bilayer Graphene Pseudospin Devices

In this paper, we examine the performance characteristics of bilayer graphene pseudospin devices as we scale the layer width of the monolayers of graphene which comprise the bilayer structure. We find that, for layer widths of 30 nm, the device performance can exceed analytical predictions due to thermal smoothing of the interlayer interactions. However, when the device is further scaled to 20 nm and below, we find an appreciable drop of the maximum current the device can sustain when compared with the predicted values which result from increased quantum interference between injected quasi-particles and those reflected off of the excitonic gap opened at the Fermi energy. These results provide important insight into the maximum achievable performance characteristics and optimal device-design parameters for this promising potential post-CMOS logic device.
Cell Behaviour During Active Cell Rearrangement: Evidence and Speculations

SUMMARY The cell behaviour and motility underlying cell rearrangement during gastrulation in amphibian and sea-urchin embryos are discussed. In particular, the cell behaviour of deep (non-epithelial) and epithelial cell populations that undergo cell rearrangement is compared and contrasted. Deep cell rearrangement in Xenopus laevis involves both convergence of cells towards the future dorsal midline and simultaneous axial extension of the mesodermal cell mass. Time-lapse cinemicrography and scanning electron microscopy suggest that asynchronous, repetitive motions of individual deep cells, involving local extensions and retractions of their margins, may provide the motive force for rearrangement. Such protrusive activity may be guided by local differences in cell–cell contacts in the marginal zone. Epithelial cell rearrangement in the sea-urchin embryo both elongates the archenteron and simultaneously closes the blastopore. Cell rearrangement is accompanied by stage-specific changes in protrusive activity and cell shape of the basal surfaces of cells in the wall of the gut rudiment, in contrast to the apical surfaces, which show little activity. These basal protrusions may be involved in the rearrangement process.
Sequential release of bioactive IGF-I and TGF-β1 from PLGA microsphere-based scaffolds

Growth factors have become an important component for tissue engineering and regenerative medicine. Insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1) in particular have great significance in cartilage tissue engineering. Here, we describe sequential release of IGF-I and TGF-β1 from modular designed poly(l,d-lactic-co-glycolic acid) (PLGA) scaffolds. Growth factors were encapsulated in PLGA microspheres using spontaneous emulsion, and in vitro release kinetics was characterized by ELISA. Incorporating BSA in the IGF-I formulations decreased the initial burst from 80% to 20%, while using uncapped PLGA rather than capped decreased the initial burst of TGF-β1 from 60% to 0% upon hydration. The bioactivity of released IGF-I and TGF-β1 was determined using MCF-7 proliferation assay and HT-2 inhibition assay, respectively. Both growth factors were released for up to 70 days in bioactive form. Scaffolds were fabricated by fusing bioactive IGF-I and TGF-β1 microspheres with dichloromethane vapor. Three scaffolds with tailored release kinetics were fabricated: IGF-I and TGF-β1 released continuously, TGF-β1 with IGF-I released sequentially after 10 days, and IGF-I with TGF-β1 released sequentially after 7 days. Scaffold swelling and degradation were characterized, indicating a peak swelling ratio of 4 after 7 days of incubation and showing 50% mass loss after 28 days, both consistent with scaffold release kinetics. The ability of these scaffolds to release IGF-I and TGF-β1 sequentially makes them very useful for cartilage tissue engineering applications.
A New Class of Buffer Overflow Attacks

In this paper, we focus on a class of buffer overflow vulnerabilities that occur due to the "placement new'' expression in C++. "Placement new'' facilitates placement of an object/array at a specific memory location. When appropriate bounds checking is not in place, object overflows may occur. Such overflows can lead to stack as well as heap/data/bss overflows, which can be exploited by attackers in order to carry out the entire range of attacks associated with buffer overflow. Unfortunately, buffer overflows due to "placement new'' have neither been studied in the literature nor been incorporated in any tool designed to detect and/or address buffer overflows. In this paper, we show how the "placement new'' expression in C++ can be used to carry out buffer overflow attacks -- on the stack as well as heap/data/bss. We show that overflowing objects and arrays can also be used to carry out virtual table pointer subterfuge, as well as function and variable pointer subterfuge. Moreover, we show how "placement new" can be used to leak sensitive information, and how denial of service attacks can be carried out via memory leakage.
MORPHEUS: motif oriented representations to purge hostile events from unlabeled sequences

Most of the prevalent anomaly detection systems use some training data to build models. These models are then utilized to capture any deviations resulting from possible intrusions. The efficacy of such systems is highly dependent upon a training data set free of attacks. "Clean" or labeled training data is hard to obtain. This paper addresses the very practical issue of refinement of unlabeled data to obtain a clean data set which can then train an online anomaly detection system.Our system, called MORPHEUS, represents a system call sequence using the spatial positions of motifs (subsequences) within the sequence. We also introduce a novel representation called sequence space to denote all sequences with respect to a reference sequence. Experiments on well known data sets indicate that our sequence space can be effectively used to purge anomalies from unlabeled sequences. Although an unsupervised anomaly detection system in itself, our technique is used for data purification. A "clean" training set thus obtained improves the performance of existing online host-based anomaly detection systems by increasing the number of attack detections.
The sintered microsphere matrix for bone tissue engineering: In vitro osteoconductivity studies

A tissue engineering approach has been used to design three-dimensional synthetic matrices for bone repair. The osteoconductivity and degradation profile of a novel polymeric bone-graft substitute was evaluated in an in vitro setting. Using the copolymer poly(lactide-co-glycolide) [PLAGA], a sintering technique based on microsphere technology was used to fabricate three-dimensional porous scaffolds for bone regeneration. Osteoblasts and fibroblasts were seeded onto a 50:50 PLAGA scaffold. Morphologic evaluation through scanning electron microscopy demonstrated that both cell types attached and spread over the scaffold. Cells migrated through the matrix using cytoplasmic extensions to bridge the structure. Cross-sectional images indicated that cellular proliferation had penetrated into the matrix approximately 700 microm from the surface. Examination of the surfaces of cell/matrix constructs demonstrated that cellular proliferation had encompassed the pores of the matrix by 14 days of cell culture. With the aim of optimizing polymer composition and polymer molecular weight, a degradation study was conducted utilizing the matrix. The results demonstrate that degradation of the sintered matrix is dependent on molecular weight, copolymer ratio, and pore volume. From this data, it was determined that 75:25 PLAGA with an initial molecular weight of 100,000 has an optimal degradation profile. These studies show that the sintered microsphere matrix has an osteoconductive structure capable of functioning as a cellular scaffold with a degradation profile suitable for bone regeneration.
Increased B7-H1 Expression on Dendritic Cells Correlates with Programmed Death 1 Expression on T Cells in Simian Immunodeficiency Virus-Infected Macaques and May Contribute to T Cell Dysfunction and Disease Progression

Suppression of dendritic cell (DC) function in HIV-1 infection is thought to contribute to inhibition of immune responses and disease progression, but the mechanism of this suppression remains undetermined. Using the rhesus macaque model, we show B7-H1 (programmed death [PD]-L1) is expressed on lymphoid and mucosal DCs (both myeloid DCs and plasmacytoid DCs), and its expression significantly increases after SIV infection. Meanwhile, its receptor, PD-1, is upregulated on T cells in both peripheral and mucosal tissues and maintained at high levels on SIV-specific CD8+ T cell clones in chronic infection. However, both B7-H1 and PD-1 expression in SIV controllers was similar to that of controls. Expression of B7-H1 on both peripheral myeloid DCs and plasmacytoid DCs positively correlated with levels of PD-1 on circulating CD4+ and CD8+ T cells, viremia, and declining peripheral CD4+ T cell levels in SIV-infected macaques. Importantly, blocking DC B7-H1 interaction with PD-1+ T cells could restore SIV-specific CD4+ and CD8+ T cell function as evidenced by increased cytokine secretion and proliferative capacity. Combined, the results indicate that interaction of B7-H1–PD-1 between APCs and T cells correlates with impairment of CD4+ Th cells and CTL responses in vivo, and all are associated with disease progression in SIV infection. Blockade of this pathway may have therapeutic implications for HIV-infected patients.
Monocyte chemotactic protein-1 elevation prior to the onset of rheumatoid arthritis among women.

Objective: To examine monocyte chemotactic protein-1 (MCP-1) concentration and future rheumatoid arthritis (RA) risk, and investigate effect modification by human leukocyte antigen-shared epitope (HLA-SE) and several lifestyle factors. Methods: We conducted a nested case–control study using stored plasma samples from the Nurses' Health Studies. Each pre-RA case was matched to three controls (Ncase= 220, Ncontrol = 675). Odds ratios (OR) for RA associated with MCP-1 concentration and interactions with HLA-SE, smoking, BMI and alcohol intake were estimated. Results: MCP-1 concentration was associated with both seropositive and seronegative RA, in particular <5 years of blood draw (OR: 2.42), and among HLA-SE positive (OR: 2.05). No interactions with smoking, BMI or alcohol were detected. Conclusion: MCP-1 was associated with risk of RA, especially among HLA-SE positive, but did not differ by smoking status, BMI or alcohol intake.
Saos-2 cell-mediated mineralization on collagen gels: Effect of densification and bioglass incorporation.

Plastic compression is a collagen densification process that has been widely used for the development of mechanically robust collagen-based materials. Incorporation of bioglass within plastically compressed collagen gels has been shown to mimic the microstructural properties of native bone and enhance in vitro cell-mediated mineralization. The current study seeks to decouple the effects of collagen densification and bioglass incorporation to understand the interplay between collagen packing density and presence of bioglass on cell-mediated mineralization. Saos-2 cell-mediated mineralization was assessed as a measure of the osteoconductivity of four different collagen gels: (1) uncompressed collagen gel (UC), (2) bioglass incorporated uncompressed collagen gel (UC + BG), (3) plastically compressed collagen gel (PC), and (4) bioglass incorporated plastically compressed collagen gel (PC + BG). The results indicated that collagen densification enhanced mineralization as shown by SEM, increased alkaline phosphatase activity and produced significantly higher amounts of mineralized nodules on PC gels compared to UC gels. Further, the amount of nodule formation on PC gels was significantly higher compared to UC + BG gels indicating that increase in matrix stiffness due to collagen densification had a greater effect on cell-mediated mineralization compared to bioglass incorporation into loosely packed UC gels. Incorporation of bioglass into PC gels further enhanced mineralization as evidenced by significantly larger nodule size and higher amount of mineralization on PC + BG gels compared to PC gels. In conclusion, collagen densification via plastic compression improves the osteoconductivity of collagen gels. Further, incorporation of bioglass within PC gels has an additive effect and further enhances the osteoconductivity of collagen gels.
Control-oriented Design of Operating Range for Linear Parameter Varying Systems for Closed-Loop Performance

An approach for multi-disciplinary design optimization is formulated for linear-parameter varying (LPV) systems that optimizes closed-loop performance. This concept searches over the design space that includes open-loop configurations and solutions to a set of linear matrix inequalities (LMI’s) that guarantee controller existence for LPV systems. In this way, this approach designs an open-loop model for which a controller exists that optimizes closed-loop performance. Surrogate-based design optimization is used to find the optimal configuration of the design variables. This approach is implemented to minimize the undesirable thermal effects on the structural dynamics of a hypersonic vehicle.
Tank Sloshing Interaction With Elastic Support Structure

A fully nonlinear 2-D σ-transformed finite difference solver has been developed based on inviscid flow equations in rectangular tanks. The fluid equations are coupled to an elastic support structure. Sloshing motion are simulated during structural vibration cycles at and outside resonance. The wave tank acts as a Tuned Liquid Damper (TLD). The TLD response is highly nonlinear due to the liquid sloshing. The solver is valid at any water depth except for small depth when shallow water waves and viscous effects would become important. Results of liquid sloshing induced by horizontal base excitations are presented for small to steep non-breaking waves. The effectiveness of the TLD is discussed through predictions of coupling frequencies of the tank-structural system for different tank sizes and mass ratios between fluid and structure. Good agreement is achieved between numerical model and first-order theory. It was found that the system response is extremely sensitive to small changes in forcing frequency. Furthermore, the solver removes the need for free-surface smoothing for the cases considered herein. The numerical model provides a quick and accurate way of determining system eigenfrequencies which can be hard to identify and interpret in physical experiments. Therefore the numerical solver could serve as a valuable guidance to physical experiments. The present studies can easily be expanded to include multiple wave tanks to investigate tank interaction effects, and thus cover suppression of a wider range of frequencies.Copyright © 2004 by ASME
Improving the analytical performance and versatility of paper spray mass spectrometry via paper microfluidics

Two paper-based microfluidic techniques, photolithography and wax patterning, were investigated for their potential to improve upon the sensitivity, reproducibility, and versatility of paper spray mass spectrometry. The main limitation of photolithography was the significant signal (approximately three orders of magnitude) above background which was attributed to the chemicals used in the photoresist process. Hydrophobic barriers created via wax patterning were discovered to have approximately 2 orders of magnitude less background signal compared to analogous barriers created using photolithography. A minimum printed wax barrier thickness of approximately 0.3 mm was necessary to consistently retain commonly used paper spray solvents (1 : 1 water : acetonitrile/methanol) and avoid leakage. Constricting capillary flow via wax-printed channels yielded both a significant increase in signal and detection time for detection of model analytes. This signal increase, which was attributed to restricting the radial flow of analyte/solvent on paper (i.e., a concentrating effect), afforded a significant increase in sensitivity (p ≪ 0.05) for the detection of pesticides spiked into residential tap water using a five-point calibration curve. Finally, unique mixing designs using wax patterning can be envisioned to perform on-paper analyte derivatization.
Geometry of guanidinium groups in arginines

The restraints in common usage today have been obtained based on small molecule X-ray crystal structures available 25 years ago and recent reports have shown that the values of bond lengths and valence angles can be, in fact, significantly different from those stored in libraries, for example for the peptide bond or the histidine ring geometry. We showed that almost 50% of outliers found in protein validation reports released in the Protein Data Bank on 23 March 2016 come from geometry of guanidine groups in arginines. Therefore, structures of small molecules and atomic resolution protein crystal structures have been used to derive new target values for the geometry of this group. The most significant difference was found for NE-CZ-NH1 and NE-CZ-NH2 angles, showing that the guanidinium group is not symmetric. The NE-CZ-NH1 angle is larger, 121.5(10)˚, than NE-CZ-NH2, 119.2(10)˚, due to the repulsive interaction between NH1 and CD1 atom.
Thoracostomy tube function not trajectory dictates reintervention

Abstract Background Hemothorax and/or pneumothorax can be managed successfully managed with tube thoracostomy (TT) in the majority of cases. Improperly placed tubes are common with rates near 30%. This study aimed to determine whether TT trajectory affects the rate of secondary intervention. Methods A retrospective review of all adult trauma patients undergoing TT placement over a 4-y period was performed. TT trajectory was classified as ideal, nonideal, or kinked-based on anterior–posterior chest x-ray. TTs with sentinel port outside the thoracic cavity were excluded. The primary outcome was any secondary intervention. Results Four-hundred eighty-six patients and a total of 547 hemithoraces underwent placement and met inclusion criteria. The majority of patients were male (76%), with a median age of 41 y, and majority suffered blunt trauma ideal trajectory was identified in 429 (78.4%). Kinked TTs were noted in 33 (6%) hemothoraces with a 45.5% replacement rate. Review with staff demonstrates inherent bias to replace kinked TTs. The overall secondary intervention rate was 27.8%. Kinked TTs were removed from final analysis due to treatment bias. Subsequent analysis demonstrated no significant difference between ideal and nonideal trajectories (25.1% versus 34.1%, P = 0.09). Conclusions Intrathoracic trajectory of nonkinked TTs with the sentinel port within the thoracic cavity does not affect secondary intervention rates, including the rate of surgical intervention.
A comparison between UWB and DSSS for use in a multiple access secure wireless sensor network

In this paper we compare the performance of two multiple access modulation schemes for use in a secure wireless sensor network. The first is binary direct sequence spread-spectrum (DSSS) while the second is ultra-wide-band pulse position modulation (UWB-PPM). Parameter values were chosen to allow each system to operate with equal bandwidths. For UWB to give a performance competitive to DSSS on an equal bandwidth and equal energy per bit basis, it is necessary to go to higher modulation orders than binary. Thus, one must give up part of the competitive advantage of UWB, namely simplicity, to obtain performance comparable to DSSS.
C-H Functionalization/activation in organic synthesis.

The last decade has seen an explosion in research reports in the area of C–H functionalization/activation in organic synthesis. This is not surprising. What is surprising is that it took many in the synthetic organic community this long to fully embrace this exciting and enabling technology. After all, organic compounds mainly consist of a carbon skeleton that bears a large number of hydrogens. It is therefore highly desirable to be able to take advantage of the myriad of C–H groups in organic molecules as functional handles for bond formation, and in some cases, bond-breaking processes.
The Static Multimodal Dyadic Behavior Dataset for Engagement Prediction

The Rapid-Attention, Back and Forth, and Communication (Rapid ABC) assessment is a semi-structured play interaction during which an examiner engages a child in five activities intended to elicit social-communication behaviors and turn taking. The examiner scores the frequency and quality of the child’s social behavior in each activity, generating a total score that reflects the child’s social engagement with her during the assessment. The standard Rapid ABC dataset contains a daunting amount of detail. We have produced a static version that captures the action-reaction dynamic of the assessment as frames. We have conducted a user study on our dataset to see if subjects can predict the engagement of a child in the video. We presented subjects both frames from our staticMMDB dataset and the full video of the original MMDB dataset and found little difference in their performance. In this paper we show that computer vision methods can predict children’s engagement. We automatically identify the ease-of-engagement of a child and provide evaluation baselines for the task.
Release of Airborne Polychlorinated Biphenyls from New Bedford Harbor Results in Elevated Concentrations in the Surrounding Air

Qualitatively and quantitatively, we have demonstrated that airborne polychlorinated biphenyl (PCB) concentrations in the air surrounding New Bedford Harbor (NBH) are caused by its water PCB emissions. We measured airborne PCBs at 18 homes and businesses near NBH in 2015, with values ranging from 0.4 to 38 ng m-3, with a very strong Aroclor 1242/1016 signal that is most pronounced closest to the harbor and reproducible over three sampling rounds. Using U.S. Environmental Protection Agency (U.S. EPA) water PCB data from 2015 and local meteorology, we predicted gas-phase fluxes of PCBs from 160 to 1200 μg m-2 day-1. Fluxes were used as emissions for AERMOD, a widely applied U.S. EPA atmospheric dispersion model, to predict airborne PCB concentrations. The AERMOD predictions were within a factor of 2 of the field measurements. PCB emission from NBH (110 kg year-1, average 2015) is the largest reported source of airborne PCBs from natural waters in North America, and the source of high ambient air PCB concentrations in locations close to NBH. It is likely that NBH has been an important source of airborne PCBs since it was contaminated with Aroclors more than 60 years ago.
Quantification and comparison of the mechanical properties of four human cardiac valves

Abstract Objective Although having the same ability to permit unidirectional flow within the heart, the four main valves—the mitral valve (MV), aortic (AV), tricuspid (TV) and pulmonary (PV) valves—experience different loading conditions; thus, they exhibit different structural integrity from one another. Most research on heart valve mechanics have been conducted mainly on MV and AV or an individual valve, but none quantify and compare the mechanical and structural properties among the four valves from the same aged patient population whose death was unrelated to cardiovascular disease. Methods A total of 114 valve leaflet samples were excised from 12 human cadavers whose death was unrelated to cardiovascular disease (70.1 ± 3.7 years old). Tissue mechanical and structural properties were characterized by planar biaxial mechanical testing and histological methods. The experimental data were then fitted with a Fung-type constitutive model. Results The four valves differed substantially in thickness, degree of anisotropy, and stiffness. The leaflets of the left heart (the AV leaflets and the anterior mitral leaflets, AML) were significantly stiffer and less compliant than their counterparts in the right heart. TV leaflets were the most extensible and isotropic, while AML and AV leaflets were the least extensible and the most anisotropic. Age plays a significant role in the reduction of leaflet stiffness and extensibility with nearly straightened collagen fibers observed in the leaflet samples from elderly groups (65 years and older). Conclusions Results from 114 human leaflet samples not only provided a baseline quantification of the mechanical properties of aged human cardiac valves, but also offered a better understanding of the age-dependent differences among the four valves. It is hoped that the experimental data collected and the associated constitutive models in this study can facilitate future studies of valve diseases, treatments and the development of interventional devices. Statement of Significance Most research on heart valve mechanics have been conducted mainly on mitral and aortic valves or an individual valve, but none quantify and compare the mechanical and structural properties among the four valves from the same relatively healthy elderly patient population. In this study, the mechanical and microstructural properties of 114 leaflets of aortic, mitral, pulmonary and tricuspid valves from 12 human cadaver hearts were mechanically tested, analyzed and compared. Our results not only provided a baseline quantification of the mechanical properties of aged human valves, but a age range between patients (51–87 years) also offers a better understanding of the age-dependent differences among the four valves. It is hoped that the obtained experimental data and associated constitutive parameters can facilitate studies of valve diseases, treatments and the development of interventional devices.
Annealing-induced precipitate formation behavior in MOVPE-grown GaAs 1-x Bi x explored by atom probe tomography and HAADF-STEM.

The effects of a 45 min anneal at 800 °C on the physical properties and microstructure of a five-period GaAs1-x Bi x /GaAs1-y Bi y superlattice with y ≠ x were studied using room-temperature photoluminesence spectroscopy, high-resolution x-ray diffraction, high-angle annular-dark-field scanning transmission electron microscopy (HAADF-STEM), and atom probe tomography (APT). The anneal resulted in a substantial increase of the photoluminesence intensity over that observed in the as-deposited sample, indicating annihilation of non-radiative recombination centers and stability of the superlattice structure during the anneal. However, some precipitation of Bi from the GaAs1-x Bi x also occurred. The characteristics of phase separation that occurred within these precipitates were investigated in detail by APT and HAADF-STEM. They indicate that the precipitation reaction involves formation of embedded nano-scale liquid droplets that can accelerate local Bi dissolution from the GaAs1-x Bi x matrix by moving through it. Preservation of nanometer scale sharp Bi concentration gradients in the growth direction suggested that very little solid state diffusion of Bi occurred during the anneal. The observed gradient in precipitate number density with distance from the sample surface further supports hypotheses of an enabling role of Ga vacancies in the precipitation process.
Nullors in amplifier design for bandwidth using multiple feedbacks

The application of nullors in bandwidth design of amplifiers are discussed. Given an analog circuit and a desirable frequency response, the proposed methodology tries to modify the circuit to follow the response from a model circuit that performs the desirable frequency response. This is done by adding one or more feedback sub-circuits to the analog circuit so that its response can follow the response from the model circuit. The method uses nullors to achieve the goal, and it works for both linear and nonlinear circuits. Although the scope of this study can be generalized and cover a wide range of cases but here we limit ourselves only to bandwidth designs, using one or more nullors. The assumption is that by including one or more feedbacks the amplifier will adequately respond to the frequency requirements as specified. Two examples show ways of expanding and shrinking of the bandwidths in amplifiers.
Oto-Mangean Languages

The Oto-Mangean stock is the most diverse genetic grouping of Meso-America, being made up of seven language families plus a branch made up of a single language. This article provides a classification, a sketch of grammatical and phonological traits, a discussion of two language-contact phenomena, and notes on comparative–historical studies, documentation, and viability. Notable phonologically are complex syllable onsets, simple syllable codas, and an average of three level tones. Grammatically noteworthy are VO morpheme order and a low degree of affixation.
Delivery of lethal dsRNAs in insect diets by branched amphiphilic peptide capsules

Development of new and specific insect pest management methods is critical for overcoming pesticide resistance and collateral off-target killings. Gene silencing by feeding dsRNA to insects shows promise in this area. Here we described the use of a peptide nano-material, branched amphiphilic peptide capsules (BAPCs), that facilitates cellular uptake of dsRNA by insects through feeding. The insect diets included dsRNA with and without complexation with BAPCs. The selected insect species come from two different orders with different feeding mechanisms: Tribolium castaneum and Acyrthosiphon pisum. The gene transcripts tested (BiP and Armet) are part of the unfolded protein response (UPR) and suppressing their translation resulted in lethality. For Acyrthosiphon pisum, ingestion of BiP-dsRNA associated with BAPCs led to the premature death of the aphids (t1/2=4-5days) compared to ingestion of the same amounts of free BiP-dsRNA (t1/2=11-12days). Tribolium castaneum was effectively killed using a combination of BiP-dsRNA and Armet-dsRNA complexed with BAPCs; most dying as larvae or during eclosion (~75%). Feeding dsRNA alone resulted in fewer deaths (~30%). The results show that complexation of dsRNA with BAPCs enhanced the oral delivery of dsRNA over dsRNA alone.
Feature based order recognition of continuous-phase FSK using principal component analysis

Principal component analysis (PCA) is a technique that performs a linear transformation on the input space to align directions of maximum variation with the directions of the axises. In this paper, we study the feasibility of principal component analysis based order recognition of continuous phase FSK. The approximate entropy (ApEn) of the received signal, ApEn of the phase of the received signal, and ApEn of the instantaneous frequency of the received signal are used as a set of distinguishing features. The work aims in devising an unsupervised learning algorithm under noisy, carrier frequency offset and fast fading channel conditions. The instantaneous frequency is shaped by using root raised cosine pulses. Performance of principal component based method is compared to stacked autoencoder (SAE) based approach which is more computationally complex technique that can model relatively complicated relationships and non-linearities. For fair comparison both the PCA and SAE based methods use approximate entropy features. The benefit of employing PCA is that after PCA transformations the computation cost can really be decreased a lot. Also in both methods, no a priori information is required about carrier phase, symbol rate and carrier amplitude. The PCA based method shows higher accuracy than the SAE method.
Cryptographic hashing using chaotic hydrodynamics.

Fluids may store and manipulate information, enabling complex applications ranging from digital logic gates to algorithmic self-assembly. While controllable hydrodynamic chaos has previously been observed in viscous fluids and harnessed for efficient mixing, its application to the manipulation of digital information has been sparsely investigated. We show that chaotic stirring of a viscous fluid naturally produces a characteristic signature of the stirring process in the arrangement of particles in the fluid, and that this signature directly satisfies the requirements for a cryptographic hash function. This includes strong divergence between similar stirring protocols’ hashes and avoidance of collisions (identical hashes from distinct stirs), which are facilitated by noninvertibility and a broad chaotic attractor that samples many points in the fluid domain. The hashing ability of the chaotic fluidic map implicates several unexpected mechanisms, including incomplete mixing at short time scales that produces a hyperuniform hash distribution. We investigate the dynamics of hashing using interparticle winding statistics, and find that hashing starts with large-scale winding of kinetically disjoint regions of the chaotic attractor, which gradually gives way to smaller scale braiding of single-particle trajectories. In addition to providing a physically motivated approach to implementing and analyzing deterministic chaotic maps for cryptographic applications, we anticipate that our approach has applications in microfluidic proof-of-work systems and characterizing large-scale turbulent flows from sparse tracer data.
CatroxMP-II: a heme-modulated fibrinogenolytic metalloproteinase isolated from Crotalus atrox venom

It has been recently demonstrated that the hemotoxic venom activity of several species of snakes can be inhibited by carbon monoxide (CO) or a metheme forming agent. These and other data suggest that the biometal, heme, may be attached to venom enzymes and may be modulated by CO. A novel fibrinogenolytic metalloproteinase, named CatroxMP-II, was isolated and purified from the venom of a Crotalus atrox viper, and subjected to proteolysis and mass spectroscopy. An ion similar to the predicted singly charged m/z of heme at 617.18 was identified. Lastly, CORM-2 (tricarbonyldichlororuthenium (II) dimer, a CO releasing molecule) inhibited the fibrinogenolytic effects of CatroxMP-II on coagulation kinetics in human plasma. In conclusion, we present the first example of a snake venom metalloproteinase that is heme-bound and CO-inhibited.
Examining Institutional Factors May Yield More Effective Policy Interventions to Improve Defense Acquisition Outcomes

The article of record as published may be located at http://dx.doi.org/10.2139/ssrn.1559910
A Benzyne Insertion Approach to Hetisine-Type Diterpenoid Alkaloids: Synthesis of Cossonidine (Davisine)

The hetisine-type natural products exhibit one of the most complex carbon skeletons within the diterpenoid alkaloid family. The use of network analysis has enabled a synthesis strategy to access alkaloids in this class with hydroxylation on the A-ring. Key transformations include a benzyne acyl-alkylation to construct a key fused 6-7-6 tricycle, a chemoselective nitrile reduction, and sequential C–N bond formations using a reductive cyclization and a photochemical hydroamination to construct an embedded azabicycle. Our strategy should enable access to myriad natural and unnatural products within the hetisine-type.
Regional Modelling of Atmospheric Aerosols

Atmospheric particles are comprised of a complex mixture of a variety of organic and inorganic substances that can be of primary or secondary nature, the size distribution of which particles can span several orders of magnitude in diameter. This complexity, together with significant gaps in knowledge of the formation and transformation processes, provides an ambitious task for the development of atmospheric particles for particulate matter. However potential impacts of these particles and the new standards for these particulate matter require the development and application of sophisticated Air Quality Models for particles.
Analysis of Lung Tumor Mortality in the Battelle Beagle Lifespan Experiment

Forty beagles in the Battelle group between 12 and 43 months of age (mean age = 562 days) were given “single, 10–30 minute inhalation exposures to 239PuO2 aerosols via a mask’ [52]. Eighteen of the original 40 dogs died with lung tumors as the primary cause of death. Seventeen died of other causes, primarily pulmonary fibrosis, and in nine of these lung tumors were in evidence even though they had not developed to the point of causing death. Finally, five dogs were sacrificed for analysis of tissue distribution of plutonium. Sacrificed animals were asymptomatic for lung tumors and none had lung tumors at autopsy. Details of the experimental procedures and results are given by Park et al. [52].
Soifer’s One-Hundred-Dollar Problem and Mitya Karabash

In 2005, the brilliant young freshman from Columbia University Mitya Karabash came to the University of Colorado at Colorado Springs, where I supervised his summer research. We looked at problems of tiling and covering, the chromatic number of the plane, and problems posed by Paul Erdős and me in this book, and wrote a joint research paper. Since then, we corresponded and wrote more joint papers. Mitya visited me several times at Princeton University. Mitya worked for years on the One-Hundred-Dollar Problem from this book, and we discussed his progress. Finally, on June 4, 2007, on the blackboard of my 7th floor Princeton office, Mitya showed me the most important result related to this book in the 18 years that have passed since its birth in 1990.
A View of the Evolution of Chemoreceptors Based on Research with Cnidarians

Since Loomis (1955) discovered that reduced glutathione (GSH) was the specific activator of feeding in Hydra littoralis, research on cnidarian chemoreceptors has taken two lines. One, involving mostly work on hydra, is concerned with elucidating the mechanism by which the receptor is activated (see Lenhoff, 1974). The other is of a more comparative nature showing that numerous compounds activate feeding in a wide range of cnidarians.
F-18 FDG positron emission tomography in a reversible form of dementia: Unexpected patterns of brain glucose metabolism in autoimmune limbic encephalitis

1238 Objectives To present two distinct metabolic patterns on FDG PET associated with non-paraneoplastic autoimmune limbic encephalitis (NPALE), an increasingly recognized and potentially reversible form of dementia that can mimic neurodegenerative disease on FDG PET. Methods Case series performed on seven patients diagnosed with NPALE who recovered completely or partially following therapy with corticosteroids. All patients received at least one FDG PET scan during the course of their illness. Results Three patients had metabolic abnormalities mimicking advanced neurodegenerative disease (e.g., Alzheimer’s disease) while a fourth patient showed similar but milder abnormalities. In contrast, three other patients demonstrated a very different and unique metabolic pattern on FDG PET, with increased temporal lobe metabolism and strikingly reduced uptake in the primary sensory and motor cortex, particularly the visual cortex. Mild or improving PET scan findings predicted an excellent clinical recovery in two patients. Conclusions Our results suggest FDG PET can be useful in the diagnosis of NPALE, but the interpreting physician must be aware of the variety of scan patterns, including one pattern that has not been described previously for any neurological disorder. It should be kept in mind when interpreting brain PET scans in patients with subacute cognitive decline that an apparent neurodegenerative pattern of cortical hypometabolism may instead represent NPALE, which is potentially reversible. Additionally, limited data suggest that mild or improving scan findings predict a good clinical outcome
Set Theory: A First Course

Set theory is a rich and beautiful subject whose fundamental concepts permeate virtually every branch of mathematics. One could say that set theory is a unifying theory for mathematics, since nearly all mathematical concepts and results can be formalized within set theory. This textbook is meant for an upper undergraduate course in set theory. In this text, the fundamentals of abstract sets, including relations, functions, the natural numbers, order, cardinality, transfinite recursion, the axiom of choice, ordinal numbers, and cardinal numbers, are developed within the framework of axiomatic set theory. The reader will need to be comfortable reading and writing mathematical proofs. The proofs in this textbook are rigorous, clear, and complete, while remaining accessible to undergraduates who are new to upper-level mathematics. Exercises are included at the end of each section in a chapter, with useful suggestions for the more challenging exercises.
Towards Defining a Quality-Metric for Affective Feedback in an Intelligent Environment

Inference-based computational models are often prone to errors. For a Context-aware Intelligent Environment (CAIE), such errors in inference may result in contextual services that are not appropriately matched with a user’s current goals resulting in negative emotional states such as frustration for the user. Learning to infer such negative emotions from a user’s psychophysiological responses may enable the CAIE to deduce an implicit feedback signal regarding this appropriateness. Pre- viously we have presented a framework for implementing this inference based affective feedback in a CAIE, including a method of ground truth data collection. We now propose a method for defining a quality metric on this inference derived from the underlying physiological processes, which is envisioned to enable us in defining a user-specific service-appropriateness feedback model. The results from the electrodermal activity (EDA) dataset collected from a Virtual-reality based Supermarket setup provide a preliminary validation to our EDA data based quality metric. Index Terms–Electrodermal Activity (EDA), Quality Metric, Affective Feedback, Psychophysiology.
Modifying the Environment and Policy Assessment and Observation (EPAO) to better capture feeding practices of family childcare home providers.

Objective To describe the modification and validation of an existing instrument, the Environment and Policy Assessment and Observation (EPAO), to better capture provider feeding practices. Design Modifications to the EPAO were made, validity assessed through expert review, pilot tested and then used to collect follow-up data during a two-day home visit from an ongoing cluster-randomized trial. Exploratory factor analysis investigated the underlying factor structure of the feeding practices. To test predictive validity of the factors, multilevel mixed models examined associations between factors and child's diet quality as captured by the Healthy Eating Index-2010 (HEI-2010) score (measured via the Dietary Observation in Childcare Protocol). Setting Family childcare homes (FCCH) in Rhode Island and North Carolina, USA.ParticipantsThe modified EPAO was pilot tested with fifty-three FCCH and then used to collect data in 133 FCCH. Results The final three-factor solution ('coercive control and indulgent feeding practices', 'autonomy support practices', 'negative role modelling') captured 43 % of total variance. In multilevel mixed models adjusted for covariates, 'autonomy support practices' was positively associated with children's diet quality. A 1-unit increase in the use of 'autonomy support practices' was associated with a 9·4-unit increase in child HEI-2010 score (P=0·001). Conclusions Similar to the parenting literature, constructs which describe coercive controlling practices and those which describe autonomy-supportive practices emerged. Given that diets of pre-schoolers in the USA remain suboptimal, teaching childcare providers about supportive feeding practices may help improve children's diet quality.
Inhibitors of aquaporins as novel anti-cancer drugs

797 Aquaporins are channel proteins that allow rapid transport of water and small molecules across the membrane. Thirteen mammalian AQPs (AQP0-AQP12) have been described and are expressed in a variety of human tissues. AQPs have recently been implicated in various diseases such as cancer, cataract, brain oedema, gallstone disease and nephrogenic diabetes insipidus, as well as in the development of obesity and polycystic kidney disease. Recently, expression of AQP1 was found to be involved in tumorigenesis. AQPs share several conserved amino acid sequences, including two asparagine-proline-alanine (NPA) motifs, with overall amino acid identities of 30-60% after sequence alignment. Peptides like vasopressin; small molecules like tetraethylammonium, acetazolamide; and metal ions all interact with AQPs. Addition of monovalent sodium ions increases the water influx whereas the addition of bivalent cations like mercury and cadmium block the transport. In the case of tetraalkyl ammonium compounds only TEA and to some extent its propyl analogue inhibit water transport. Other tetraalkyl ammonium analogues methyl, butyl, pentyl, hexyl do not inhibit water transport. It is also reported that fertilizers like DDT and surfactants like n-octylglycosides could interact with AQP. Such differential binding indicates the specificity and affinity of AQP-ligand interation. We hypothesize that metal ions and small molecules in water recognize specific motifs in the loop structure thereby controlling the 3D structure, pore constriction and hence modulating water permeability. A combination of sequence analysis and molecular modeling were used to test the hypothesis. We have constructed a comprehensive Protein-Metal Ion Site-frequency (ProMIS) dataset by mining RCSB-Protein Data Bank (http://www.rcsb.org/pdb) and Protein ligand interaction using occluded surfaces analysis post structural modeling. Based on a scoring matrix constructed from ProMIS, we evaluated the likelihood of common mono/bivalent metal ions interaction with the AQP loops. Loop E sequences of most of the mammalian AQPs showed higher ProMIS scores for the bivalent metal ions Hg2+ and Cd2+ in comparison to the loops A or C suggesting a site for biomolecular control of water transport. Tetraalkyl ammonium compounds specifically interacted with charged residues in the C and E loop. Our observations provide valuable insight into membrane protein recognition, ionic control of water transport and structural basis for anti-cancer drug discovery. Acknowledgements: Mississippi NSF-EPSCoR “Innovations through Computational Sciences” Award (EPS-0556308); Interdisciplinary Undergraduate Training in Biological and Mathematical Sciences (DMS-0531927); and the Research Centers in Minority Institutions (RCMI) - Center for Environmental Health (NIH-NCRR G12RR13459-09)