cssi/SciSciGPT-SciSciNet huggingface dataset:
Securing ZigBee Communications Against Constant Jamming Attack Using Neural Network

ZigBee is a wireless communication technology that has been widely used to provide low-bandwidth wireless services for Internet-of-Things applications, such as building automation, medical data collection, and industrial equipment control. As ZigBee operates in the industrial, scientific and medical radio frequency bands, it may suffer from unintentional interference from coexisting radio devices (e.g., WiFi and Bluetooth) and/or radio jamming attacks from malicious devices. Although many results have been produced to enhance ZigBee security, there is no technique that can secure ZigBee against jamming attack. In this article, we propose a new ZigBee receiver by leveraging MIMO technology, which is capable of decoding its desired signal in the presence of constant jamming attack. The enabler is a learning-based jamming mitigation method, which can mitigate the unknown interference using an optimized neural network. We have built a prototype of our proposed ZigBee receiver on a wireless testbed. Experimental results show that it is capable of decoding its packets in the face of 20-dB stronger jamming. The proposed ZigBee receiver offers an average of 26.7-dB jamming mitigation capability compared to off-the-shelf ZigBee receivers.
Hyperspectral Image Classification Using Fisher's Linear Discriminant Analysis Feature Reduction with Gabor Filtering and CNN

Deep learning-based approaches for hyperspectral image (HSI) feature extraction and classification have gained popularity in recent years. Effective extraction of spectral and spatial information is desired for classifying HSI using a convolutional neural network (CNN) to avoid overfitting. Previous research suggests that Fisher's linear discriminant analysis (LDA) is a better alternative for HSI feature reduction compared to principal component analysis (PCA). In this work, an LDA approach is studied as a dimensionality reducer along with a Gabor filter for extracting spatial features and classification using CNN. The efficacy of the proposed approach is compared with a similar classification scheme with the PCA. Experimental results from two benchmark HSI datasets show the benefits of using LDA with notable improvements in class and overall accuracies.
Reducing write amplification in flash by death-time prediction of logical block addresses

Flash-based solid state drives lack support for in-place updates, and hence deploy a flash translation layer to absorb the writes. For this purpose, SSDs implement a log-structured storage system introducing garbage collection and write-amplification overheads. In this paper, we present a machine learning based approach for reducing write amplification in log structured file systems via death-time prediction of logical block addresses. We define death-time of a data element as the number of I/O writes before which the data element is overwritten. We leverage the sequential nature of I/O accesses to train lightweight, yet powerful, temporal convolutional network (TCN) based models to predict death-times of logical blocks in SSDs. We leverage the predicted death-times in designing ML-DT, a near-optimal data placement technique that minimizes write amplification (WA) in log structured storage systems. We compare our approach with three state-of-the-art data placement schemes and show that ML-DT achieves the lowest WA by utilizing the learnt I/O death-time patterns from real-world storage workloads. Our proposed approach results in up to 14% reduction in write amplification compared to the best baseline technique. Additionally, we present a mapping learning technique to test the applicability of our approach to new or unseen workloads and present a hyper-parameter sensitive study.
Determining the Association Between Unplanned Reoperation and Readmission in Selected General Surgery Operations

Abstract Background Unplanned reoperations and unplanned readmissions can increase morbidity and mortality. Few studies however, have explored the association of reoperation and readmission among general surgery patients. Our aim was to examine this relationship in selected abdominal operations. Methods Data from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Participant Use Data Files from 2014 to 2018 were utilized. Six groups of operations, defined by ACS NSQIP procedure codes for ventral hernia repair, colectomy, appendectomy, proctectomy, small bowel resection, and gastrectomy, were assessed. Patients discharged ≤ 14 days after operation were included in the study. This time period was selected to reduce ACS NSQIP 30 day post-surgery follow-up bias. Unplanned reoperations were defined as those occurring during the index hospitalization. The primary outcome was unplanned readmission that occurred ≤ 14 days from the date of discharge. Logistic regression models were used to examine variables associated with unplanned readmission for each procedure group. Results A total of 787,118 patients were included: ventral hernia repair 35.2%, colectomy 30.6%, appendectomy 26.5%, proctectomy 3.7%, small bowel resection 3.2%, and gastrectomy 0.8%. Unplanned reoperation was independently associated with unplanned readmission for ventral hernia repair (OR 2.84, 95% CI 2.28-3.54, P Conclusions Unplanned reoperations are associated with an increase in unplanned readmission after selected abdominal operations included in this study. This factor should be considered in discharge and follow-up planning to help reduce unplanned readmissions.
Public understanding of climate change terminology

The United Nations’ Intergovernmental Panel on Climate Change (IPCC) and other institutions communicate about climate change to diverse audiences without a background in climate science, including the general public. The effectiveness of these communications depends in part on how well the presented terminology is understood. In qualitative interviews, we examined how US residents interpreted key terms drawn from IPCC reports, including tipping point, unprecedented transition, carbon neutral, carbon dioxide removal, adaptation, mitigation, sustainable development, and abrupt change. We recruited twenty participants with diverse views on climate change from a nationally representative sample. We identified common themes and misunderstandings. Overall, 88% of the themes arose by the tenth interview, and no new themes arose after the seventeenth interview. Mitigation, carbon neutral, and unprecedented transition were perceived as the most difficult to understand. Adaptation and abrupt change were perceived as the easiest to understand. However, even if a term appeared to be understood, participants were not always clear about how it applied to climate change. Participants tended to draw on their mental models of non-climate contexts where terms had different meanings. Reading the terms in the context of sentences taken from communication materials was not always helpful due to the use of complex language. Based on participants’ interpretations and the science communication literature, we provide suggestions for communicating about each term. Generally, recommendations are to simplify wording, make links to climate change explicit, and describe underlying processes. Our findings are relevant to climate change communications by the IPCC and other institutions.
Additively Manufactured Conformal Feeds for Passive Beamforming

Designing low cost, broadband and wide scan angle beamforming systems is critical for a diverse range of commercial and military applications. Many current beamforming approaches either involve complex phased arrays or large mechanically steered antennas. The phased arrays are often prohibitively expensive while the mechanically steered systems are often too slow, heavy, and susceptible to mechanical failures. An alternative approach involves the use of graded index (GRIN) RF lenses as passive beamformers. Recently the reliable fabrication of RF GRIN lenses is made possible with the use of advanced additive manufacturing (AM) systems and materials. Through AM, GRIN based RF lenses have recently been reported that possess high radiation efficiencies, high antenna gains, and ultra-wideband operations [1] . Current GRIN devices, while greatly improved, still often lack the wide-angle steering and efficient conformal feed structures needed for some of the more challenging applications. In this presentation, we describe the design and fabrication, via additive manufacturing, of an array of conformal feeds. When integrated with a graded index beamforming lens, such as the Luneburg lens or modified versions, results in an ultra-wide scan angle beam steering device. Specifically, we will describe the design and fabrication, via AM, of an integrated beam steering device that combines: (1) printed conformal RF connectors, (2) printed broadband baluns, (3) printed broadband feed antennas, and (4) a novel GRIN lens.
Language, Cognition, and the Brain: Insights From Sign Language Research

Once signed languages are recognized as natural human languages, a world of exploration opens up. Signed languages provide a powerful tool for investigating the nature of human language and language processing, the relation between cognition and language, and the neural organization of language. The value of sign languages lies in their modality. Specifically, for perception, signed languages depend upon high-level vision and motion processing systems, and for production, they require the integration of motor systems involving the hands and face. These facts raise many questions: What impact does this different biological base have for grammatical systems? For online language processing? For the acquisition of language? How does it affect nonlinguistic cognitive structures and processing? Are the same neural systems involved? These are some of the questions that this book aims at addressing. The answers provide insight into what constrains grammatical form, language processing, linguistic working memory, and hemispheric specialization for language. The study of signed languages allows researchers to address questions about the nature of linguistic and cognitive systems that otherwise could not be easily addressed.
Above-Knee Amputation

Above-the-knee amputation (AKA) is a last-resort surgical option for the treatment of periprosthetic joint infection (PJI) with resistant organisms or with recurrent infections. Certain circumstances are unique to performing AKAs after total knee arthroplasty (TKA). When performing an AKA, the factors that require special attention include the indications for surgery, presentation and comorbidities, level of amputation, possible prosthesis removal, and potential complications. This chapter includes a discussion of the surgical techniques, postoperative stump care, options for prostheses, functional status, and long term follow up after AKA. This chapter provides comprehensive and relevant information for assessing, performing, and treating AKA patients after infected TKAs.
The Level and Structure of Executive Compensation within the Insurance Industry

In this paper we examine the prevailing level and structure of executive compensation within the insurance industry. We analyze the level of base pay, annual bonus, long-term compensation, and option grants of 836 executive positions at 92 companies of various sizes in 1999 and 2001. The data allow an introspective look at the manner in which the top management teams within the insurance industry were compensated during this period, and extend previous studies on insurance executive compensation beyond the CEO position. We examine the level of compensation across executive rank and find evidence supporting the tournament compensation model. We also find that compensation structure across executive pay ranks is similar within small and medium-size insurance companies but different within large companies.
Carbon nanotube-guided thermopower waves

Thermopower waves are a new concept for the direct conversion of chemical to electrical energy. A nanowire with large axial thermal diffusivity can accelerate a self-propagating reaction wave using a fuel coated along its length. The reaction wave drives electrical carriers in a thermopower wave, creating a high-power pulse of as much as 7 kW/kg in experiments using carbon nanotubes. We review nanomaterials designed to overcome limitations of thermoelectricity and explore the emerging scientific and practical outlook for devices using thermopower waves.
Comparison of seven methods for producing Affymetrix expression scores based on False Discovery Rates in disease profiling data

A critical step in processing oligonucleotide microarray data is combining the information in multiple probes to produce a single number that best captures the expression level of a RNA transcript. Several systematic studies comparing multiple methods for array processing have used tightly controlled calibration data sets as the basis for comparison. Here we compare performances for seven processing methods using two data sets originally collected for disease profiling studies. An emphasis is placed on understanding sensitivity for detecting differentially expressed genes in terms of two key statistical determinants: test statistic variability for non-differentially expressed genes, and test statistic size for truly differentially expressed genes. In the two data sets considered here, up to seven-fold variation across the processing methods was found in the number of genes detected at a given false discovery rate (FDR). The best performing methods called up to 90% of the same genes differentially expressed, had less variable test statistics under randomization, and had a greater number of large test statistics in the experimental data. Poor performance of one method was directly tied to a tendency to produce highly variable test statistic values under randomization. Based on an overall measure of performance, two of the seven methods (Dchip and a trimmed mean approach) are superior in the two data sets considered here. Two other methods (MAS5 and GCRMA-EB) are inferior, while results for the other three methods are mixed. Choice of processing method has a major impact on differential expression analysis of microarray data. Previously reported performance analyses using tightly controlled calibration data sets are not highly consistent with results reported here using data from human tissue samples. Performance of array processing methods in disease profiling and other realistic biological studies should be given greater consideration when comparing Affymetrix processing methods.
Gestational nicotine exposure reduces nicotinic cholinergic receptor (nAChR) expression in dopaminergic brain regions of adolescent rats.

Children of women who smoked during pregnancy are at increased risk of dependence when smoking is initiated during adolescence. We previously reported that gestational nicotine exposure attenuated dopamine release induced by nicotine delivered during adolescence. In this study, we determined the effects of gestational nicotine exposure on nicotinic cholinergic receptor (nAChR) expression. Timed pregnant rats received nicotine (2 mg/kg/day) or vehicle via mini-osmotic pumps during gestation. Treatments continued in pups via maternal nursing during postnatal days (PN) 2-14 (equivalent to the human in utero third trimester). On PN35, 1 2 5 I-epibatidine binding to nAChR was measured. The B m a x values (fmol/mg) in prefrontal cortex (PFC), nucleus accumbens (NAcc), substantia nigra (SN) and ventral tegmental area (VTA) were reduced by 26.6% (P < 0.05), 32.6% (P < 0.01), 23.0% (P < 0.01) and 27.6% (P < 0.05), respectively. In addition, gender differences were found in vehicle-treated groups; in SN and VTA, females were 79.3% (P < 0.005) and 82.9% (P = 0.08) of males, respectively. The expression of nAChR subunit mRNAs was measured using real-time RT-PCR on laser-capture microdissected tissues. In adolescent VTA, gestational nicotine exposure reduced (P < 0.05) nAChR subunit mRNAs encoding a3 (53.0%), α4 (23.9%), a5 (46.7%) and β4 (61.4%). In NAcc core, the treatment increased α3 mRNA (75.8%). In addition, the number of neurons in VTA was reduced by 15.0% (P< 0.001). These studies indicate that gestational exposure to nicotine induces long-lasting changes in nAChR expression that may underlie the vulnerability of adolescents to dependence on nicotine.
Binding of rabies virus to purified Torpedo acetylcholine receptor.

Abstract The binding of 125I- and 35S-labeled rabies virus (CVS strain) to affinity-purified acetylcholine receptor from Torpedo electric organ was demonstrated. The binding of rabies virus to the acetylcholine receptor increased with increasing receptor concentration, was dependent on the pH of the incubation medium, and was saturable with increasing virus concentration. Binding of radioactively labeled virus was effectively competed by unlabeled homologous virus particles. Binding of 35S-labeled rabies virus to the AChR was inhibited up to 50% by α-bungarotoxin and up to 30% by (+)-tubocurarine but was not affected by atropine. These results demonstrate direct binding of rabies virus to a well-defined neurotransmitter receptor, namely the acetylcholine receptor and indicate that at least a portion of the virus interaction occurs near the acetylcholine binding site on the receptor. These findings support the hypothesis that the acetylcholine receptor may serve as a rabies virus receptor in vivo.
Sialic acid metabolism in rat liver: Effect of carbon tetrachloride

Sialic acid metabolism was investigated in the livers of control rats and of rats treated with a single oral dose (1.5 ml/kg body weight) of carbon tetrachloride. The main change observed during the necrotic stage of CCl4 poisoning (18 h after treatment) was a highly significant reduction in sialyltransferase activity. Slight reciprocal changes in neuraminidase activities, i.e., a small decrease in cytosolic neuraminidase and a small increase in the membrane bound enzyme were also observed. At 72 h after CCl4 treatment, during the stage of liver regeneration, the main change was a marked elevation in membrane-bound neuraminidase (two fold above control values). Moderate increases in the specific activities of CMP-N-acetylneuraminic acid synthetase and sialyltransferase were also observed. A considerable decrease in the sialic acid content of the isolated smooth endoplasmic reticulum (one half of control values) was detected at 72 h after CCl4 administration. The sialic acid content of the rough endoplasmic reticulum, on the other hand, remained at control levels.
Immigrants and Their Communities: A Review Essay

The historical literature on America's "new immigrants" has come a long way since the publication of Oscar Handlin's Pulitzer Prize-winning volume, The Uprooted, in 1951. Frank Thistlethwaite since has shown how nineteenthand early twentieth century migration was not a one-way ticket between Europe and America, but an international exchange which involved the flow of resources, capital, and labor back and forth in an integrated Atlantic economy. Other historians, meanwhile, have called into question Handlin's understanding of immigrant culture. Rudolph Vecoli and Herbert Gutman, for example, both have demonstrated that Handlin should not have characterized America's migrants as "the uprooted," for they were trans planted ? transplanting themselves ? into cultural soil they carried with them from their countries of origin. Finally, revisionist scholars also since have criticized a longstanding view popularized by Handlin, although certainly not invented by him, namely, that immigrants were history's victims. From one side, Timothy Smith and his students have argued that America's migrants were "on the make," i.e., upwardly mobile men and women who seized opportunity when and where they could find it and who thus embraced the prevailing work ethic and success myths of their adop tive country. Taking another, very different tack, Victor Greene, Gutman, and the large numbers of researchers they influenced persuasively insisted that working-class immigrants were neither passive objects nor helpless victims. Instead, these histo rians found that the experiences of America's working-class immigrants resembled those of the nineteenth-century English workers whom E.P. Thompson and other
Adducts of titanium tetrachloride with organosulfur compounds. Crystal and molecular structures of TiCl4(C4H8S)2 and (TiCl4)2(CH3SSCH3)

Abstract Treatment of titanium tetrachloride with a range of organothiols affords adducts of the formula TiCl4(HSR)2 in 77–89% yields. Reaction of titanium tetrachloride with organic sulfides gives sulfide adducts of the formula TiCl4(SR2)2 in 87–98% yields. These complexes are volatile and monomeric with cis-organosulfur ligands. Treatment of titanium tetrachloride with methyl disulfide affords the adduct (TiCl4)2(CH3SSCH3) in 98% yield, which adopts a dinuclear structure with a Ti2Cl8 core and a bridging disulfide ligand. The crystal structures of TiCl4(C4H8S)2 and (TiCl4)2(CH3SSCH3) were determined. The relevance of these observations to the chemical vapor deposition of titanium disulfide and trisulfide films is discussed.
Systemwide cost control--the missing link in health care reform.

The health care reform legislation now before Congress cannot be relied on to control spending. Jonathan Oberlander and Joseph White describe an option that could control spending across both the public and private insurance pools.
Assessing SNPs Versus RAPDs for Predicting Heterogeneity and Screening Efficiency in Wild Potato ( Solanum ) Species

Knowing how genetic diversity is partitioned among and within wild potato species populations is important for efficient sampling for collection, preservation and evaluation. We sought to evaluate the effectiveness of SNPs for assessing germplasm by using the exact set of four model species previously evaluated by RAPDs. To avoid large numbers of SNP samples, population bulks of 25 plants were used, and original RAPD data was adjusted to match SNP genotype data. It was noted that especially for SNPs, it was necessary to examine only loci polymorphic within species to get a realistic view of genetic partitioning within species. This resulted in only a few hundred useful loci for some species. When considering among-population versus within-population partitioning of diversity, both SNPs and RAPDs distinguished the species as expected according to their known breeding system. Primitive wild species were confirmed as very heterogeneous within their populations. Both SNP and RAPD markers can be used to help breeders and genebank managers understand patterns and use in potato germplasm diversity.
Successful integration of fixed and removable prosthodontics

The management of complex prosthodontics requires special consideration during treatment as well as maintenance visits after treatment is complete. The anticipated design of the removable partial denture framework must be recorded prior to restorative procedures. Preparation of the abutment teeth should provide space for the critical portions of the removable partial denture that will require subsequent restorations. Portions of a removable partial denture essential to the construction of a restoration are guide planes, rests, retentive clasps, and reciprocal components. The wax patterns of the restorations should be contoured on a surveyor in harmony with the path of insertion and design of removable partial dentures. Successful integration of fixed and removable prosthodontics is dependent on adequate diagnostic information and perceptive execution of restorative procedures.
Varicella-Zoster virus glycoprotein gE: Endocytosis and trafficking of the Fc receptor

Varicella-zoster virus (VZV) encodes a functional cell membrane Fc receptor called glycoprotein gE. VZV gE resembles other mammalian cell membrane receptors, such as the mammalian Fc receptor. In further analyses by transient transfection, the cellular trafficking of VZV gE was compared to other cell surface receptors. VZV gE was shown to undergo endocytosis from the cell membrane when visualized by laser scanning confocal microscopy. The endocytosis and trafficking pathway of VZV gE followed closely the pathway defined for the human transferrin receptor. Receptor-mediated endocytosis of VZV gE was dependent on a YAGL motif in its cytoplasmic tail. In addition, VZV gE underwent receptor-mediated endocytosis when it bound the Fc portion of immunoglobulin. Thus, this detailed study of VZV gE cellular trafficking has revealed potential roles for gE during viral infection.
CN1: UTILITIES OF METASTATIC BREAST CANCER PATIENTS (PT) TREATED WITH TAXANES COMPARED TO UTILITIES OF ONCOLOGY NURSES (NUR)

Cost-utility analysis is rapidly becoming the standard pharmacoeconomic measure in oncology. In a recent report (JCO, 2000;18:3302), data from 40 published cost-utility studies were presented in a league table format. Most of those studies utilized nurses or physicians as proxies for the pt. in determining utility. OBJECTIVE: To determine if there is a difference between utility scores obtained from metastatic breast cancer pt. and oncology nurses. METHODS: Using eight modified Markov modeled health states (Pharmacoeconomics, 1996; 60:504) describing metastatic breast cancer; the standard gamble procedure was utilized to obtain utility scores from 45 patients and 57 oncology nurses. Utility values were measured on a scale between 0.0 and 1.0. Independent t-tests were used to test for differences between groups using an alpha level of 0.05 (2-sided). RESULTS: Significant differences were found on all eight modeled health states: CONCLUSION: These results show that patients have a higher utility for health than perceived by nurses. These data leads to the question of whose utility values should be used for cost-utility analysis in oncology. Modeled Disease State Mean Utility Score (SD) Patients/Nurses (n = 45; n = 57) P Value 95% Confidence Intervals Partial Response (PR) .84 (.11)/.71 (.22) .0001 .06–.20 PR with Severe Peripheral Edema .78 (.17)/.63 (.24) .0001 .08–.24 PR with Severe Peripheral Neuropathy .76 (.13)/.56 (.24) .0001 .12–.28 Before Second Line Treatment Begins .73 (.16)/.59 (.22) .0001 .06–.22 Stable Disease .72 (.15)/.54 (.22) .0001 .11–.26 Late Progressive Disease .63 (.18)/.45 (.25) .0001 .10–.27 Terminal Disease .40 (.26)/.19 (.21) .0001 .13–.31 Sepsis .39 (.25)/.20 (.23) .0001 .09–.28
Bcl-2 regulation of mitochondrial energetics.

Recent data suggest that in addition to regulating apoptosis, Bcl-2 (an anti-apoptotic protein overexpressed in B-cell lymphoma) and Bcl-2 family members also regulate mitochondrial and cell physiology. t-Bid, a Bcl-2 family member, has been shown to modulate reorganization of mitochondrial cristae. Bcl-2 appears to regulate voltage-dependent anion channel permeability, which has important consequences for mitochondrial transport of adenine nucleotides, Ca 2+ , and other metabolites. BAD, a pro-apoptotic Bcl-2 family member, is required for the binding of glucokinase to a mitochondrial complex, and BAD null mice have altered glucose homeostasis. It has been suggested that Bcl-2 family members may regulate important mitochondrial/cell functions and serve as sentinels to detect abnormalities in these pathways and, when the abnormalities are severe enough, to initiate or facilitate cell death. Understanding the physiologic processes controlled by Bcl-2 will be important in understanding cell regulation, and it may also provide new insights into the regulation of apoptosis.
Selection of Dairy Cows for Economic Merit

Abstract Selection of dairy cows for economic merit requires the use of a model for genetic merit that involves the cross-product of the genetic values for milk and milk fat percentage. A linear and a quadratic index are described as procedures for selection of cows, the linear index being b 1 p m + b 2 p t and the quadratic index being b 1 p m + b 2 p t + b 2 p m 2 + b 4 p t 2 + b 5 p m p t where p m and p t are the phenotypic deviations for milk and milk fat percentage, respectively, and the b 's are selection index weights. These indices are compared to one another and to other possible selection procedures in terms of the expected genetic progress in economic merit that would result from their use. Predicted gains are maximum for the quadratic index. Relative to these gains, the gains from the linear index are nearly equivalent, while those from a restricted index and a simplified form of the quadratic index are somewhat less, the extent of the decrease depending on the means for milk and milk fat percentage. Gains in economic merit from selection for milk are only slightly less than those from the quadratic index at all but very high mean levels of milk production. Selection for milk thus appears to be a reasonable selection procedure to improve economic merit, except at high mean levels of milk production. Changes in the parameters of milk production and milk fat percentage and in economic values could affect these comparisons.
New finite element formulation for electromechanics

A new finite element formulation for the solution of electromechanical boundary value problems is presented. As opposed to the standard formulation that utilizes a scalar electric potential as nodal variables, this new formulation implements a vector potential from which components of electric displacement are derived. For linear piezoelectric materials with positive definite material moduli, the resulting finite element stiffness matrix from the vector potential formulation is also positive definite. If the material is nonlinear in a fashion characteristic of ferroelectric materials, it is demonstrated that a straightforward iterative solution procedure is unstable for the standard scalar potential formulation, but stable for the new vector potential formulation. Finally, the method is used to compute fields around a crack tip in an idealized non-linear ferroelectric material, and results are compared to an analytical solution.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Tuning the tetraethylammonium sensitivity of potassium channel Kcv by subunit combination

Tetraethylammonium (TEA) is a potassium (K+) channel inhibitor that has been extensively used as a molecular probe to explore the structure of channels’ ion pathway. In this study, we identified that Leu70 of the virus-encoded potassium channel Kcv is a key amino acid that plays an important role in regulating the channel’s TEA sensitivity. Site-directed mutagenesis of Leu70 can change the TEA sensitivity by 1,000-fold from ∼100 µM to ∼100 mM. Because no compelling trends exist to explain this amino acid’s specific interaction with TEA, the role of Leu70 at the binding site is likely to ensure an optimal conformation of the extracellular mouth that confers high TEA affinity. We further assembled the subunits of mutant and wt-Kcv into a series of heterotetramers. The differences in these heterochannels suggest that all of the four subunits in a Kcv channel additively participate in the TEA binding, and each of the four residues at the binding site independently contributes an equal binding energy. We therefore can present a series of mutant/wild-type tetramer combinations that can probe TEA over three orders of magnitude in concentration. This study may give insight into the mechanism for the interaction between the potassium channel and its inhibitor.
Optical transitions in carbon nanotubes

Analytical expressions for the optical matrix elements of semiconducting carbon nanotubes are obtained for different polarizations of the incident light. It is shown that, for the light polarized along the nanotube axis and transitions between the extrema of electronic subbands, the optical matrix element only weakly depends on the nanotube chirality and excitation energy. It is found that, for the light polarized in the plane perpendicular to the nanotube axis, both ${v}^{2}\ensuremath{\rightarrow}{c}^{1}$ and ${v}^{1}\ensuremath{\rightarrow}{c}^{2}$ transitions are allowed.
Enantioselective synthesis and enantiomeric amplification of amino acids under prebiotic conditions.

A plausible origin of biomolecular homochirality is advanced, where α-methyl amino acids found on meteorites transfer their chirality in the synthesis of normal amino acids. This asymmetry can be amplified to nearly homochiral levels, thus providing the necessary prerequisite for life to start on this planet and elsewhere in the universe.
Hierarchical coding of 2D mesh geometry and motion

This paper proposes methods for construction and compression of hierarchical representations of 2D moving meshes. This representation consists of a hierarchy of Delaunay meshes, using image-based and shape-based criteria for mesh geometry simplification. The hierarchical compression technique is based on a nearest-neighbor ordering of mesh node points. This ordering serves to define the mesh boundary as well as a spatial prediction relation on the nodes, which is employed for differential node point location and motion vector coding. The proposed compression methods allow progressive transmission and quality scalability. The proposed hierarchical mesh representation can be applied in object-based video coding, storage and manipulation. Experimental results are provided comparing the compression performance of non-hierarchical coding and hierarchical coding, and evaluating the trade-off between mesh-based video object rendering quality and hierarchical mesh bitrate.
Why We Should take Performance Measurement on Faith (Facts Being Hard to Come by and Not Terribly Important)

(2002). Why We Should take Performance Measurement on Faith (Facts Being Hard to Come by and Not Terribly Important) Public Performance & Management Review: Vol. 25, No. 4, pp. 375-380.
Dutasteride reduces alcohol’s sedative effects in men in a human laboratory setting and reduces drinking in the natural environment

Rationale Preclinical studies support the hypothesis that endogenous neuroactive steroids mediate some effects of alcohol.
Michael Collins Piper: An American Far Right Emissary to the Islamic World

Abstract This essay examines the career of Michael Collins Piper, an important figure in the American far right subculture. A prolific writer, his underground books advancing various conspiracy theories have in recent years found a receptive audience in the Islamic world. Casting himself as an alternative media representative, he has conferred with leading statesmen, including Deputy Prime Minister of the United Arab Emirates Sultan Ibn Zayd al‐Nahayan, former Malaysian Prime Minister Dr Mahathir Muhammad and Iranian President Mahmud Ahmadinejad. His outreach could presage greater cooperation between segments of the far Right and the Muslim world in the future.
Using the shape recovery method to evaluate indexing techniques

Text representation, central to information processing, must be descriptive and discriminative. Although some of the many techniques to construct document representations may outperform others for certain tasks, no one is consistently better than others. Representations are still problematic. Evaluation techniques are needed to penetrate foundational questions about term behavior in representation. A study that applies the shape recovery analysis method is reported here as an evaluative tool to compare different indexing schemes. Three weight coefficients are used to rank indexing terms and are compared to the documents' full text. Two of the weight coefficients are novel and the third relies on the chi-squared distribution. Multidimensional scaling reduces the dimensional space of the document surrogates into a two-dimensional Cartesian space. Ten concentric circles evenly separated at 10% intervals of relevant data points starting at the centroid are used to construct a precisionrecall curve. ANOVA is used for a straightforward computation of the 4 x 11 matrix of test data to see whether the four treatments yield the same P-R result. A post hoc HSD Tukey multiple comparisons test among pairwise treatments is also used to discover homogeneous groups. The findings show the value of the methodology to study term weighting schemes, and their descriptiveness and discriminative power, as well as the potential strength of the novel coefficients introduced. © 2008 Wiley Periodicals, Inc.
Beyond 7-azaindole: Conjugation effects on intermolecular double hydrogen-atom transfer reactions

Conjugation effects on the thermodynamics of ground-state and lowest-singlet excited-state double hydrogen-atom transfer reactions in 7-azaindole and related models are studied with ab initio electronic structure methods. The results indicate that the extended conjugation of the system has a large effect on the relative energies required for hydrogen-atom transfer. The observed energy differences are mainly attributed to stabilization of the tautomer species by enhancing low-energy resonance structures and by allowing for efficient delocalization of excess charge in the reaction center.
Defect chemistry of lone-pair semiconductors

Abstract A chemical-bond approach reveals the possibility of several unusual bonding configurations that have relatively low energy in materials with lone-pair valence electrons. Valence-alternation pairs (V.A.P.) are the lowest energy charged defects. The interconversion between positive and negative centres is described in detail. The nature of V.A.P.s in pnictides (group V elements) is discussed. The possibility that valence-alternation centres can form intimate or bound pairs is explored. It is pointed out that certain unusual bonding configurations (configuration distortions) arise even in an ideal lone-pair material. It is stressed that the unusual bonding configurations discussed are a result of the special bonding in lone-pair materials and are, therefore, expected to arise in crystals as well as amorphous materials.
Design of a systolic-pipelined architecture for real-time enhancement of color video stream based on an illuminance-reflectance model

A high performance digital architecture for the implementation of a nonlinear image enhancement technique is proposed in this paper. The image enhancement is based on an illuminance-reflectance model which improves the visual quality of digital images and video captured under insufficient or non-uniform lighting conditions. The algorithm shows robust performance with appropriate dynamic range compression, good contrast, accurate and consistent color rendition. The algorithm contains a large number of complex computations and thus it requires specialized hardware implementation for real-time applications. Systolic, pipelined and parallel design techniques are utilized effectively in the proposed FPGA-based architectural design to achieve real-time performance. Approximation techniques are used in the hardware algorithmic design to achieve high throughput. The video enhancement system is implemented using Xilinx's multimedia development board that contains a VirtexII-X2000 FPGA and it is capable of processing approximately 63 Mega-pixels (Mpixels) per second.
Positive and Negative Feedback Effects of Ovarian Steroids on Luteinizing Hormone Release in Ovariectomized Rats following Chronic Depletion of Hypothalamic Norepinephrine

The involvement of central noradrenergic mechanisms in the feedback control of LH secretion was studied in ovariectomized rats. Permanent depletion of hypothalamic norepinephrine (NE) was accomplished by transecting the ascending noradrenergic pathway (ANP) in the midbrain. A postcastration elevation in serum LH was observed in rats with complete transections of the ANP, and although the rise was somewhat slower than that seen in sham-cut animals, there was no significant difference between the two groups 5 weeks or more after ovariectomy. Both the positive and negative feedback actions of ovarian steroids remained intact after chronic depletion of NE, and animals with transections of the ANP actually had greater responses than sham-cut controls. In addition, phenoxybenzamine, an a-adrenergic receptor blocker which effectively blocked the steroid-induced LH surge in six of eight sham-cut animals, was ineffective in NE-depleted rats. These results support the concept that NE acts as a modulator of LH secre...
Rapidly labeled RNA associated with ribosomes of tobacco leaves infected with tobacco mosaic virus

Abstract Sucrose density gradient analysis of the RNA extracted from ribosomes of actinomycin D-treated and labeled tobacco leaf tissue infected with TMV showed that the radioactivity was incorporated approximately equally in 18 S RNA and in a small amount of low-molecular weight RNA of high specific activity. When ribosomes were dissociated with EDTA, the radioactivity was similarly approximately equally apportioned between low-molecular weight, highly labeled RNA and nucleoprotein particles sedimenting as the 40 S ribosomal subunit.
The dissociation dynamics of energy-selected neopentylamine ions: Heats of formation of neopentylamine and neopentyl alcohol

Abstract The dissociation dynamics of energy-selected neopentylamine cations, (CH3)3CCH2NH2+, were studied using threshold photoelectron photoion coincidence (TPEPICO) spectroscopy in which ion time-of-flight (TOF) distributions are recorded as a function of the ion internal energy. The lowest energy pathway, producing the CH3NH3+ ion, involves a rearrangement of the molecular ion. The 0 K dissociation onsets for the production of the CH3NH3+, CH2NH2+, and (CH3)2CCH2NH2+ ions have been determined to be 9.54 ± 0.05, 9.647 ± 0.025 and 9.90 ± 0.1 eV, respectively. Because the heat of formation of the CH2NH2+ + t-C4H9 products are established, we can use the measured onset of 9.647 eV for this reaction to establish the neopentylamine Δ f H 298 ° = − 130.3 ± 3.3 kJ / mol . This result is used in a group additivity scheme to estimate the neopentyl alcohol heat of formation as Δ f H 298 ° = − 315.5 ± 4 kJ mo l − 1 . Both of these results are strongly supported by a series of isodesmic reactions calculated at the G3B3 and CBS-APNO levels. This is the first reported experimental heat of formation of the neopentylamine and the first reported heat of formation of the neopentyl alcohol.
Introduction of the American Pediatric Society's 2010 John Howland Award recipient, Charles R. Scriver, MDCM.

Introduction of the American Pediatric Society's 2010 John Howland Award Recipient, Charles R. Scriver, MDCM
Absorption and distribution of intubated insecticides in fasted mice

Abstract Radioactive solutions of 14 C-labeled insecticides were administered by stomach needle to fasted female mice (1 mg/kg, Dublin strain). They were killed at different time intervals and the amount of radioactivity determined in the gastrointestinal tract (unabsorbed) and in selected organs. T 0.5 values of penetration (min) ranged from 8 to 17 for the carbamates tested, 24 to 78 for the organophosphorus compounds, and 15 to 62 for the chlorinated hydrocarbons. Among other insecticide groups, nicotine penetrated rapidly whereas permethrin was the least rapid of all compounds under study. The insecticides were rapidly distributed to various organs. No consistent correlations between absorption and physicochemical properties of the compounds were noted.
A Statistical Procedure for Detecting Highly Correlated Genes with a Pre-Specified Candidate Gene in Microarray Analysis

We propose a statistically valid two-stage procedure for selecting genes with expression levels correlated with that of a ‘seed’ gene in microarray experiments: Stage I: perform array-normal–scores (ANS) transformation of the raw microarray data and calculate the Pearson correlation coefficients using ANS-transformed data, and Stage II: calculate a resampling-based BH (rsBH) least significant-false discovery rate (LS-FDR), named to select most correlated genes based on a given LS-FDR threshold. By using simulated data sets, we show that the proposed ANS transformation is needed even after the usual data normalization process. The ANS transformation improves the detection of correlated genes, particularly the negatively correlated genes. We demonstrated the proposed procedure by searching for genes involved in insulin resistance and type 2 diabetes mellitus on a dataset the from Human Gene Expression Index (HugeIndex) database.
Variables affecting collaborative research and learning in a professional development school partnership

Abstract The authors investigated the influence of group and task variables on perceived organizational and team learning by school and university participants in collaborative inquiry partnership groups in a professional development school (PDS). Participants included 58 teachers and administrators and 10 university faculty members and graduate students. Group variables included leadership style (task oriented and human relations oriented), leadership composition, cohesion, collaboration, and group size. Task variables included task importance and task type (compensatory, conjunctive, discretionary, and disjunctive). A significant amount of variance in perceived team learning was accounted for by the combined group and task variables, but the task variables as a group did not account for significant variation over that accounted for by the group variables. Only task-oriented leadership, cohesion, and task importance accounted for unique sources of variance in perceived team learning. A significant amount...
Visualizing T Cell Migration in situ.

Mounting a protective immune response is critically dependent on the orchestrated movement of cells within lymphoid tissues. The structure of secondary lymphoid organs regulates immune responses by promoting optimal cell-cell and cell-extracellular matrix interactions. Naive T cells are initially activated by antigen presenting cells in secondary lymphoid organs. Following priming, effector T cells migrate to the site of infection to exert their functions. Majority of the effector cells die while a small population of antigen specific T cells persist as memory cells in distinct anatomical locations. The persistence and location of memory cells in lymphoid and non-lymphoid tissues is critical to protect the host from re-infection. The localization of memory T cells is carefully regulated by several factors including the highly organized secondary lymphoid structure, the cellular expression of chemokine receptors and compartmentalized secretion of their cognate ligands. This balance between the anatomy and the ordered expression of cell surface and soluble proteins regulates the subtle choreography of T cell migration. In recent years, our understanding of cellular dynamics of T cells has been advanced by the development of new imaging techniques allowing in-situ visualization of T cell responses. Here we review the past and more recent studies that have utilized sophisticated imaging technologies to investigate the migration dynamics of naive, effector and memory T cells.