cssi/SciSciGPT-SciSciNet huggingface dataset:
Defending against vehicular rogue APs

This paper considers vehicular rogue access points (APs) that rogue APs are set up in moving vehicles to mimic legitimate roadside APs to lure users to associate to them. Due to its mobility, a vehicular rogue AP is able to maintain a long connection with users. Thus, the adversary has more time to launch various attacks to steal users' private information. We propose a practical detection scheme based on the comparison of Receive Signal Strength (RSS) to prevent users from connecting to rogue APs. The basic idea of our solution is to force APs (both legitimate and fake) to report their GPS locations and transmission powers in beacons. Based on such information, users can validate whether the measured RSS matches the value estimated from the AP's location, transmission power, and its own GPS location. Furthermore, we consider the impact of path loss and shadowing and propose a method based on rate adaption to deal with advanced rogue APs. We implemented our detection technique on commercial off-the-shelf devices including wireless cards, antennas, and GPS modules to evaluate the efficacy of our scheme.
On weak monotonicity of the powers of nonnegative matrices

The purpose of this paper is to study conditions under which the powers of a square matrix A are weak monotone. Necessary and sufficient conditions under which the product of any two weak monotone matrices is weak monotone are also obtained. Several examples are given to illustrate the necessity of the conditions stated.
OSMOTICALLY LYSED RAT LIVER MITOCONDRIA : Biochemical and Ultrastructural Properties in Relation to Massive Ion Accumulation

Osmotically lysed rat liver mitochondria have been utilized for a study of the biochemical and ultrastructural properties in relation to divalent ion accumulation. Osmotic lysis of mitochondria by suspension and washing in cold, distilled water results in the extraction of about 50% of the mitochondrial protein, the loss of the outer mitochondrial membrane, an increase in respiration, and a marked decrease in the ability to catalyze oxidative phosphorylation. Nevertheless, except for a decrease in the ability to accumulate Sr(2+) by an ATP-supported process, these lysed mitochondria retain full capacity to accumulate massive amounts of divalent cations by respiration-dependent and ATP-supported mechanisms. The decreased ability of osmotically lysed mitochondria to accumulate Sr(2+) by an ATP-energized process does not appear to be due to a loss or inactivation of a specific Sr(2+)-activated ATPase. The energy-dependent accumulation processes in lysed mitochondria show an increased sensitivity to inhibition by monovalent cations. Extraction of cytochrome c from osmotically lysed mitochondria results in a complete loss of phosphorylation and the respiration-dependent accumulation of Ca(2+); a lesser, but significant, decrease in the ATP-supported accumulation of Ca(2+) also was observed. The addition of cytochrome c fully restores the respiration-dependent accumulation of Ca(2+) to the level present in unextracted, osmotically lysed mitochondria. The ATP-supported process is not affected by the addition of cytochrome c to extracted mitochondria, indicating that cytochrome c is not involved in ion transport energized by ATP. The osmotically lysed mitochondria are devoid of outer membranes and contain relatively little matrix substance. The accumulation of Ca(2+) and P(i) by lysed mitochondria under massive loading conditions is accompanied by the formation of electron-opaque deposits within the lysed mitochondria associated with the inner membranes. This finding suggests that the inner membrane plays a role in the deposition of divalent ions within intact rat liver mitochondria. The relevance of these observations to those of other investigators is discussed.
Hyaluronan and Layilin Mediate Loss of Airway Epithelial Barrier Function Induced by Cigarette Smoke by Decreasing E-cadherin

Cigarette smoke (CigS) exposure is associated with increased bronchial epithelial permeability and impaired barrier function. Primary cultures of normal human bronchial epithelial cells exposed to CigS exhibit decreased E-cadherin expression and reduced transepithelial electrical resistance. These effects were mediated by hyaluronan (HA) because inhibition of its synthesis with 4-methylumbelliferone prevented these effects, and exposure to HA fragments of <70 kDa mimicked these effects. We show that the HA receptor layilin is expressed apically in human airway epithelium and that cells infected with lentivirus expressing layilin siRNAs were protected against increased permeability triggered by both CigS and HA. We identified RhoA/Rho-associated protein kinase (ROCK) as the signaling effectors downstream layilin. We conclude that HA fragments generated by CigS bind to layilin and signal through Rho/ROCK to inhibit the E-cadherin gene and protein expression, leading to a loss of epithelial cell-cell contact. These studies suggest that HA functions as a master switch protecting or disrupting the epithelial barrier in its high versus low molecular weight form and that its depolymerization is a first and necessary step triggering the inflammatory response to CigS.
WD-40 Repeat Region Regulates Apaf-1 Self-association and Procaspase-9 Activation

The casp9 protein plays a critical role in apoptosis induced by a variety of death stimuli. A regulator of apoptosis, Apaf-1, binds to and activates pro-casp9 in the presence of cytochrome c and dATP, a requirement that is bypassed by deletion of the WD-40 repeats located in the C-terminal half of Apaf-1. In this report, we used constitutively active Apaf-1 mutant lacking the WD-40 repeat region to study the mechanism and regulation of pro-casp9 activation. Mutational analysis revealed that only a small portion of the CED-4 homologous region (residues 456–559) could be deleted without destroying the ability of Apaf-1-(1–559) to activate pro-casp9. Apaf-1 can self-associate to form oligomers. Disruption of Apaf-1 self-association by deletion (Δ109–559) or mutation of the P-loop region (K149R) abrogated Apaf-1-mediated pro-casp9 activation. Forced oligomerization of the caspase recruitment domain of Apaf-1 was sufficient for pro-casp9 activation. Dimerization of chimeric Fpk-pro-casp9 protein with the dimerizer drug FK1012 induced pro-casp9 processing and apoptosis in cells. Significantly, the C-terminal region containing WD-40 repeats interacted with its N-terminal CED-4 homologous region, as determined by immunoprecipitation experiments. Importantly, expression of the WD-40 repeat region inhibited Apaf-1 self-association and proteolytic activation of pro-casp9. These studies provide a mechanism by which Apaf-1 promotes autoactivation of pro-casp9 through Apaf-1 self-association, a process that is negatively regulated by the WD-40 repeats.
An anomaly of the x-ray spectrum of graphite in the region of the Raman band

Abstract In the spectrum of polycrystalline graphite, an anomaly has been found in the inelastic X-ray scattering. The anomaly occurs at a distance of about 311 eV from the primary line. The anomaly is ascribed to the transition of core electrons to the anti-bonding band of graphite.
Inhibition of P‐Enolpyruvate Carboxykinase and of Glyconeogenesis in Tetrahymena by 3‐Mercaptopicolinic Acid*

SYNOPSIS. Tetrahymena grown overnight in deep cultures were incubated for 1 hr with [1-14C]labeled substrates in the presence or absence of 3-mercaptopicolinic acid (3-MPA). 3-MPA inhibited appearance of label in glycogen from bicarbonate, acetate, pentanoate, octanoate, and succinate, but not from glycerol or glucose. In vitro assays of phosphoenolpyruvate carboxylase and phosphoenolpyruvate carboxykinase activity showed that both enzymes were about equally distributed between the particulate and cytosol fractions. 3-MPA inhibited phosphoenolpyruvate carboxykinase from both the cytoplasmic and particulate fractions, but had no effect on phosphoenolpyruvate carboxylase from either location. These results suggest that the in vivo effects of this drug are due to inhibition of glyconeogenesis at this site.
Absolute cross sections for charge capture from Rydberg targets by slow highly charged ions.

A crossed beam experiment has been used to measure absolute charge capture cross sections in collisions of slow highly charged xenon ions with laser excited Rydberg atoms. The cross sections were measured for scaled projectile velocities {ital nv}{sub {ital p}} from 1.0 to 6.0, for projectile charges of 8, 16, 32, and 40, where {ital n} is the principal quantum number of the target electron. Experimental cross sections are compared with predictions of classical models.
Pleasure, empowerment, and love: Factors associated with a positive first coitus

Descriptions of adolescents’ first coital experiences have typically focused on the negative affect reported by women or on sex differences in levels of positive affect. Analyses of factors associated with a positive first coitus are rare. Accordingly, we examined correlates of a pleasurable first coital experience among 335 undergraduates. Analyses focused on three elements of a positive sexual experience—positive emotionality (e.g., happy), empowerment, and feelings of love—and on four groups of potential correlates: context of the first experience, parental socialization messages, gender attributes and beliefs, and body satisfaction. Each of these four domains emerged as significant correlates. Results suggested that a more intentional (vs. spontaneous) first experience, exposure to parental messages about sexual freedom, less adherence to “traditional” gender roles, and greater body satisfaction were related to a more positive first coital experience. These findings suggest that comprehensive sexual education programs would likely facilitate positive sexual development.
Electrochemical Behavior of Alloy 22 in 5 M CaCl2

The corrosion resistance of Alloy 22 (UNS No. N06022) was studied in 5 M CaCl2 electrolyte at various temperatures. Potentiodynamic polarization was used to examine the electrochemical behavior and measure the key potentials. Alloy 22 was found to be susceptible to localized corrosion in this high-chloride [10 M Cl− ] environment at temperatures as low as 60°C.Copyright © 2002 by ASME
Versatile diastereoselectivity in formal [3,3]-sigmatropic shifts of substituted 1-alkenyl-3-alkylidenecyclobutanols and their silyl ethers.

A new method for the preparation of highly substituted cyclohexenones is reported. [2 + 2] Cycloaddition of 2-silyloxydienes with allenecarboxylate affords the 1-alkenyl-3-alkylidenecyclobutanol silyl ethers. Thermolysis of these compounds affords the methylene cyclohexenyl silyl ethers with excellent exo selectivity (>95:5) when monosubstituted alkenyl groups are used, while the use of disubstituted alkenyl groups gives generally low selectivity (∼2:1). However, rearrangement of the anion of the cyclobutanol (prepared by acidic hydrolysis of the TMS silyl ether) at low temperature gives the endo product with good to excellent diastereoselectivity (5−23:1). Two different mechanistic rationales are given for the two different processes: the first via a diradical and the second via a cleavage intramolecular Michael addition. Thus, the same starting material (e.g., 20) can be converted into either the exo or endo product, 22x or 22n, with good diastereocontrol by just changing the rearrangement conditions.
Corneal epithelium-specific mouse keratin K12 promoter.

Keratins are structural proteins expressed by epithelial cells. Approximately 30 different keratin proteins have been identified, each with a specific expression pattern in different epithelial cells. The tissue-specific promoter of several keratin genes have been used to direct the expression of transgenes in animals. Keratin K12 and K3 are expressed in differentiated and stratified corneal epithelium, although the relative expression of each appears to vary between species. We targeted the mouse K12 keratin gene in order to develop a tissue-specific promoter that could be utilized to study the functions of genes of interest expressed in the corneal epithelium. Three 5' truncated fragments of the keratin K12 promoter (1.03, 0.71 and 0.25 Kb) showed higher functional and tissue-specific promoter activity in a human corneal epithelial cell line than other cell lines. The 0.25 Kb K12 promoter fragment was also active in cultured rabbit corneal epithelial cells. Thus, increased expression in corneal epithelial cells directed by fragments of the mouse K12 promoter extended across species lines. The paired box homeotic gene 6 (PAX-6), which is involved in controlling eye development, stimulated the activity of keratin K12 promoter.
Non-autonomous dynamics of a nonlinear spin-torque nano-oscillator

A theory of non-autonomous dynamics of a strongly nonlinear spin-torque nano-oscillator in the presence of external periodic and/or chaotic (e.g. thermal noise) signals is developed. This theory is based on the nonlinear oscillator equation for the complex amplitude c(t) of a spin wave excited by spin-polarized current [1]
Esophagectomy first: A shift in the treatment algorithm for regionally advanced cancer? Only with brains and brawn

Withelegantstatistics,Zahoor andcolleagues attheUniversity of Pittsburgh, the hub of the minimally invasive approach for surgical resection, present in this issue of the Journal a propensity-matched outcome analysis comparing patients undergoing upfront minimally invasive esophagectomy (MIE) for esophageal adenocarcinoma with those treated with neoadjuvant therapy followed by MIE. They try to bring down the wall built on a number of studies but cemented by the Chemoradiotherapy for Oesophageal CancerFollowedbySurgeryStudy(CROSS)trialendorsing neoadjuvant chemoradiation for all regionally advanced cases. 1 Thehypothesiswasthatpatientstreatedwithupfront surgical resection, followed by adjuvant therapy for those with clinical stageIIB orgreater disease,wouldhavea comparable overall survival to those undergoing neoadjuvant therapy (chemotherapy alone or chemoradiation) followed by surgical resection. All the patients had adenocarcinoma, and all underwent MIE. The conclusions? Upfront MIE (1) did not negatively affect overall survival, (2) allowed accurate pathologic staging, and (3) allowed downstaging so that 10% of patients did not need adjuvant therapy. The results are compelling . for surgeons who choose the minimally invasive approach. Zahoor and colleagues are not arguing any other way. That is their audience. Can they sway the advocates of open approaches to a less invasive procedure? The argument for many clinicians to offer the patient neoadjuvant therapy is that many patients will not tolerate adjuvant therapy if indicated after resection. Although it has not been reported specifically for MIE, allow me to extrapolate from the video-assisted thoracoscopic lobectomy literature 2 and recent quality-of-life reports comparing MIE and open approaches. 3 A mini
Design issues in optical data storage

We present an introduction to some of the critical considerations in designing pickup systems for optical data storage.
Management of the soil-plant-atmosphere complex

The area of land which man manipulates through cultivation is 3.2×109 ha; however, the impact from this system has been large. The soil-plant-atmosphere complex is very dynamic with the plant continually growing throughout a constantly changing atmospheric environment, i.e., radiation, temperature, and precipitation. However, a basis for all exchanges is the energy balance and all changes are made through this balance.
Forward masking recovery and peripheral compression in normal‐hearing and cochlear‐impaired ears

Iso‐response temporal masking curves are obtained from normal‐hearing subjects at a probe frequency of 1000 Hz for masker frequencies between 500 and 1200 Hz. Time constants calculated from the temporal masking curves varied with masker frequency, from around 70 ms for low off‐frequency maskers (500–600 Hz) to around 36 ms for on‐frequency maskers (close to the probe frequency). Continuing Bilger’s earlier pursuits of nonlinearities in hearing, estimates of peripheral compression were calculated under the assumption that the response to a low off‐frequency masker is linear at the probe frequency place. Average compression exponents varied from close to 1.0 for remote off‐frequency maskers (both below and above the probe) to below 0.4 for on‐frequency maskers. Input–output transfer functions derived from the compression exponents were consistent with BM transfer functions recorded in animals with normal cochlear function. Comparisons of iso‐response temporal masking curves in subjects with sizable cochlear hearing losses at the probe frequency yielded linear transfer functions consistent with BM data from cochlear‐damaged animals. It is concluded that time constants for recovery from forward masking in ears with cochlear hearing loss are no different than those obtained from normal‐hearing ears, once differences in peripheral compression are taken into account. [Work supported by NIH‐NIDCD Grant DC00149 and the Lion’s 5M International Hearing Foundation.]
Comparison of neural activity that leads to true memories, false memories, and forgetting: An fMRI study of the misinformation effect

False memories can occur when people are exposed to misinformation about a past event. Of interest here are the neural mechanisms of this type of memory failure. In the present study, participants viewed photographic vignettes of common activities during an original event phase (OEP), while we monitored their brain activity using fMRI. Later, in a misinformation phase, participants viewed sentences describing the studied photographs, some of which contained information conflicting with that depicted in the photographs. One day later, participants returned for a surprise item memory recognition test for the content of the photographs. Results showed reliable creation of false memories, in that participants reported information that had been presented in the verbal misinformation but not in the photographs. Several regions were more active during the OEP for later accurate memory than for forgetting, but they were also more active for later false memories, indicating that false memories in this paradigm are not simply caused by failure to encode the original event. There was greater activation in the ventral visual stream for subsequent true memories than for subsequent false memories, however, suggesting that differences in encoding may contribute to later susceptibility to misinformation.
Effect of PTFE content in microporous layer on water management in PEM fuel cells

Abstract The effect of hydrophobic agent (PTFE) concentration in the microporous layer on the PEM fuel cell performance was investigated using mercury porosimetry, water permeation experiment, and electrochemical polarization technique. The mercury porosimetry and water permeation experiments indicated that PTFE increases the resistance of the water flow through the GDL due to a decrease of the MPL porosity and an increase of the volume fraction of hydrophobic pores. When air was used as an oxidant, a maximum fuel cell performance was obtained for a PTFE loading of 20 wt.%. The experimental polarization curves were quantitatively analyzed to determine the polarization resistances resulting from different physical and electrochemical processes in the PEM fuel cell. The polarization analysis indicated that the optimized PTFE content results in an effective water management (i.e., a balancing of water saturations in the catalyst layer and the gas diffusion layer), thereby improving the oxygen diffusion kinetics in the membrane-electrode assembly.
A priori and a posteriori approaches for finding genes of evolutionary interest in non-model species: Osmoregulatory genes in the kidney transcriptome of the desert rodent Dipodomys spectabilis (banner-tailed kangaroo rat)

One common goal in evolutionary biology is the identification of genes underlying adaptive traits of evolutionary interest. Recently next-generation sequencing techniques have greatly facilitated such evolutionary studies in species otherwise depauperate of genomic resources. Kangaroo rats (Dipodomys sp.) serve as exemplars of adaptation in that they inhabit extremely arid environments, yet require no drinking water because of ultra-efficient kidney function and osmoregulation. As a basis for identifying water conservation genes in kangaroo rats, we conducted a priori bioinformatics searches in model rodents (Mus musculus and Rattus norvegicus) to identify candidate genes with known or suspected osmoregulatory function. We then obtained 446,758 reads via 454 pyrosequencing to characterize genes expressed in the kidney of banner-tailed kangaroo rats (Dipodomys spectabilis). We also determined candidates a posteriori by identifying genes that were overexpressed in the kidney. The kangaroo rat sequences revealed nine different a priori candidate genes predicted from our Mus and Rattus searches, as well as 32 a posteriori candidate genes that were overexpressed in kidney. Mutations in two of these genes, Slc12a1 and Slc12a3, cause human renal diseases that result in the inability to concentrate urine. These genes are likely key determinants of physiological water conservation in desert rodents.
Myosin heavy chain isoform expression is not altered in the pectoralis major muscle in selenium-deficient chickens recovering from exudative diathetic myopathy.

Abstract The recovery of broiler chickens experiencing skeletal muscle myopathy caused by a selenium deficiency was compared with control broiler chickens in an age matched study by ultrastructural analysis of the pectoralis major (PM) muscle and examination of the temporal expression of the developmental fast skeletal myosin heavy chain (MyHC) isoforms. Selenium-deficient chicks showing signs of exudative diathesis (ED) were injected subcutaneously with sodium selenite in water and allowed to recover. At 0, 2, 5, 10, 20, and 30 d after selenium injection, a sample of the PM muscle was removed from selenium-deficient and control chicks for analysis. Ultrastructural analysis revealed vacuolization in the PM of selenium-deficient chicks with little or no visible damage to the sarcomere. Relative amounts of chicken ventricular, embryonic, neonatal, and adult fast skeletal MyHC isoforms were determined using chicken fast skeletal MyHC isoform specific monoclonal antibodies. The temporal expression of the developmental MyHC isoforms was similar in all chickens (P > 0.05). There was no expression of chicken ventricular MyHC observed in the PM of either group. These results indicate that chicken fast muscle recovering from exudative diathetic myopathy does not use the same pathways as chicken skeletal fast muscle regenerating from physical or toxic injury in which temporal expression of the MyHC isoforms is initially predominantly ventricular, then predominantly embryonic, neonatal, and finally predominantly adult developmental MyHC isoform.
PD 404,182 Is a Virocidal Small Molecule That Disrupts Hepatitis C Virus and Human Immunodeficiency Virus

We describe a virucidal small molecule, PD 404,182, that is effective against hepatitis C virus (HCV) and human immunodeficiency virus (HIV). The median 50% inhibitory concentrations (IC50s) for the antiviral effect of PD 404,182 against HCV and HIV in cell culture are 11 and 1 μM, respectively. The antiviral activity of PD 404,182 is due to the physical disruption of virions that is accompanied to various degrees (depending on the virus and exposure temperature/time) by the release of viral nucleic acids into the surrounding medium. PD 404,182 does not directly lyse liposomal membranes even after extended exposure, and it shows no attenuation in antiviral activity when preincubated with liposomes of various lipid compositions, suggesting that the compound inactivates viruses through interaction with a nonlipid structural component of the virus. The virucidal activity of PD 404,182 appears to be virus specific, as little to no viral inactivation was detected with the enveloped Dengue and Sindbis viruses. PD 404,182 effectively inactivates a broad range of primary isolates of HIV-1 as well as HIV-2 and simian immunodeficiency virus (SIV), and it does not exhibit significant cytotoxicity with multiple human cell lines in vitro (50% cytotoxic concentration, >300 μM). The compound is fully active in cervical fluids, although it exhibits decreased potency in the presence of human serum, retains its full antiviral potency for 8 h when in contact with cells, and is effective against both cell-free and cell-associated HIV. These qualities make PD 404,182 an attractive candidate anti-HIV microbicide for the prevention of HIV transmission through sexual intercourse.
The acute sensory neuronopathy syndrome: A distinct clinical entity

Four to twelve days following initial antibiotic treatment for a febrile illness, three adults suddenly experienced numbness and pain over the face and entire body. Each had received a penicillin or a semisynthetic derivative, and two patients also received other antibiotics. Signs appeared rapidly and included profound sensory ataxia, areflexia, and widespread sensory loss, primarily of large fiber modalities (proprioceptive sensibility). Slowed or absent sensory conduction was found. There was no weakness, and electrical study of muscle and motor nerve conduction was normal in all. The cerebrospinal fluid was acellular, and protein levels were elevated to 126 and 175 mg/dl in two cases and were normal in the other. Presently, all have a severe, static, residual sensory deficit. During follow-up of five years, no evidence of neoplastic disease or immunological disorder has appeared. Because of the rapid onset, widespread and pure sensory involvement, and poor recovery, the lesion is most likely confined to the dorsal root and gasserian ganglia (sensory neuronopathy). This pattern resembles that of the experimental lesions induced by doxorubicin and pyridoxine. It appears likely that either the previously administered antibiotics or the illness for which they were administered were of pathogenetic importance. We designate this previously unrecognized disorder the acute sensory neuronopathy syndrome and suggest that it represents a distinct, readily identifiable clinical entity.
Ply angle effect on fiber composite wrapped reinforced concrete beam–column connections under combined axial and cyclic loads

Abstract This paper presents a numerical analysis to investigate the effect of ply angle on the improvement of shear capacity and ductility of beam–column connections strengthened with carbon fiber-reinforced polymer (CFRP) wraps under combined axial and cyclic loads. Three-dimensional nonlinear finite element models for the beam–column connections were developed and simulated with the Marc.Mentat™ 2001 finite element analysis (FEA) software. An experimental study on an FRP-wrapped beam–column connection, which was previously reported in the literature, was utilized to validate the accuracy of the proposed finite element models. The FEA study entailed profiling the behavior of three beam–column connections that were strengthened through the CFRP wrapping with various ply angle configurations. Analysis results indicated that four layers of wrapping placed successively at ±45° ply angles with respect to the horizontal axis is the most suitable upgrade scheme for improving shear capacity and ductility of beam–column connections under combined axial and cyclic loads.
Smoked cocaine self-administration by humans is not reduced by large gabapentin maintenance doses

Abstract Previously, we reported that gabapentin, a λ-aminobutyric acid (GABA) agonist, significantly reduced “positive” subjective effects of cocaine without reducing cocaine self-administration. We speculated that the gabapentin doses used in that study were too low to detect subtle shifts in the reinforcing effects of cocaine. Thus, the present study examined the effects of larger gabapentin maintenance doses on cocaine-related effects, including self-administration. During this 48-day double-blind, crossover design study, the effects of gabapentin maintenance (0, 2400, 3200 mg/day) on response to cocaine (0, 12, 25, 50 mg) were investigated in six cocaine-dependent individuals not seeking treatment for their cocaine use. Active cocaine significantly increased choice to self-administer cocaine, subjective-effect ratings (e.g., “Good Drug Effect”), blood pressure, and heart rate. Gabapentin did not decrease cocaine self-administration, cardiovascular measures, or most subjective effects of cocaine. These data agree with findings from a clinical trial examining the effects of similar gabapentin doses on cocaine use by treatment-seeking cocaine-dependent individuals and suggest that gabapentin does not show promise as a treatment medication for cocaine dependence.
Final-state symmetry and polarization effects in angle-resolved photoemission spectroscopy☆

Abstract Certain collection geometries used in photoemission experiments on oriented single crystals imply, in the one-electron picture, a definite selection of initial-and final-state symmetries. The principle is applied to recent polarization experiments on W(001) surfaces.
Phoenix Landing Site Hazard Assessment and Selection

The Phoenix Mars Scout landing site hazard assessment and selection process began with a survey of the latitude band from 65–72 N to identify candidate landing regions that were accessible, safe, and suitable for meeting the mission science objectives. Four candidate landing regions were identified based upon proximity of ground ice to the surface. Thermal inertia data, visible imagery, and topographicmapswere combined tomake an initial assessment of rock abundance and slopes. Broadly distributed high-resolution images enabled refined interpretation of the lowerresolution data sets. Based upon this assessment, a broad valley to thewest ofHeimdall crater at 68.3 N, 124.6 Wwas selected as the target landing region for the Phoenix mission. A detailed evaluation of this region resulted in the identification of eight different geologic units, with each unit exhibiting characteristic terrain type and rock abundances. Targeted high-resolution images were acquired across much of the region. An autonomous rockcounting algorithm was used to develop probabilistic risk distributions. Landing ellipse placement was selected to maximize the probability of a safe landing considering rock and slope hazards, including craters. Postlanding images from the Phoenix stereoscopic imager show a landing site generally devoid of hazardous rocks and slopes, consistent with predictions.
Studies with the schistosomacide hycanthone: inhibition of macromolecular synthesis and its reversal.

Abstract The new schistosomacide, hycanthone, was studied with regard to its effects upon macromolecular synthesis in mammalian (HeLa) cells. At concentrations as low as 5 × 10−8M, hycanthone reduces plating efficiency of HeLa cells. At 10−6M, effects on population growth are evident by the second generation. At 5 × 10−6M, RNA synthesis is markedly depressed while DNA and protein synthesis are relatively unaffected. New ribosomal RNA synthesis is rapidly inhibited by hycanthone at 5 × 10−6M, and its processing is markedly delayed. During hycanthone inhibition 28S RNA does not appear in the cytoplasm. Hycanthone inhibition was shown to be readily reversible by washing the cells in fresh medium. The case with which inhibition can be reversed in vitro suggests that it may be necessary to maintain blood levels of this compound if permanent eradication of schistosomal infection is to be attained. Further work must be done to establish this point.
Academic Elite in Psychology, 1982–1995

Szimmary.-The ten most highly rated doctoral programs in psychology in 1982 maintained their positions in 1995. These "elite" programs showed little or no change in their tendencies to hire faculty members from among their own and one another's graduates. Of the universities with the 10 top-ranked doctoral programs in psychology in 1982, as rated by the National Academy of Sciences (2), 55.6% of their faculty members had obtained their doctoral degrees from one of these same ten top-ranked schools (1). This suggested these programs had maintained and enhanced their reputations by hiring their own and one another's graduates. Here, doctoral programs in psychology, ranked 12 years later by the National Research Council (3) were examined for (a) which of the ten psychology programs ranked highest in 1982 retained their high rankings in 1995 and (b) which persisted in hiring their own and one another's graduates. The universities with these ten programs and their respective ranks in 1982 and 1995 are Stanford 1 and 1, Yale 2 and 3, Pennsylvania 3 and 8, Michigan 4 and 2, Minnesota 4 and 7, California at Berkeley 7 and 9, Harvard 7 and 6, Ihnois 7 and 5, Caldornia at Los Angeles 9 and 4, and Carnegie Mellon 10 and 11. Each of the ten programs ranked highest in 1982 was ranked among the top 11 programs in 1995 (p = .58) The names and alrna maters of the full-time faculty in the ten programs in 1982 and 1995 were obtained from college catalogs downloaded from the internet. The median percentage of faculty who had obtained their doctoral degrees from their own school or from one of the other nine top-ranked schools in 1995 was 51.4% (range, 41.4%-65.3%); cf. 53.4% (range, 39.1% -75.0%) in 1982.
Rat brain enkephalinase: Characteristion of the active site using mercaptopropanoyl amino acid inhibitors, and comparison with angiotensin-converting enzyme

Over fifty mercaptopropanoyl amino acids and related derivatives were synthesized to define the steric, electronic and stereochemical requirements for binding to the active site of enkephalinase (ENKASE), and also for their ability to inhibit angiotensin-converting enzyme (ACE). In this way the character of ENKASE and ACE active sites were compared.
Evolution of the genetic code

The origin of the genetic code is not merely an evolutionary juggling of codon assignments until some optimal configuration is achieved. It is, rather, the more interesting and profound problem of how codon assignments arose. This is part and parcel of the origin of a translating mechanism. A plausible scheme for the evolution of translation starting from a simple class of nucleic acid components is presented. Such an evolution may appear unique, idiosyncratic, when viewed only in terms of structural details. However, in its general features, on a more fundamental level, this evolution is a prototype study in the refinement of a process, in the emergence of macro-order. In approaching the evolution of the genetic code the biologist will be forced to reexamine many of his fundamental prejudices, indeed, the meaning of Biology itself.
Electrodeposition of FeCoNiCu nanowires

Electrodeposition of FeCoNiCu/Cu nanometric, compositionally modulated alloy nanowires is presented. Pure Cu nanowires and Co-rich FeCoNiCu alloy nanowires were deposited from a single electrolyte. A double potential pulse scheme was used for multilayer deposition and significant anodic dissolution was observed during the low potential pulse. Galvanostatic triple pulses with a relaxation period were developed to minimize the local pH rise inside the nanopores during fabrication of the layered FeCoNiCu/Cu nanowires.
High proportions of mtDNA duplications in patients with Kearns‐Sayre syndrome occur in the heart

Kearns-Sayre syndrome (KSS) is a sporadic multisystem mitochondrial disorder characterized by progressive external ophthalmoplegia, pigmentary retinopathy, onset before age 20, and severe cardiac conduction defects that can lead to death. KSS patients harbor partial deletions of mitochondrial DNA (delta-mtDNA), sometimes associated with the corresponding mtDNA duplication (dup-mtDNA). As reports on the distribution of dup-mtDNAs among KSS tissues are scarce, we searched for the presence of dup-mtDNAs in different autopsy tissues of two such patients, one of whom carried the so-called "common deletion." Using a newly developed long polymerase chain reaction (PCR) protocol in conjunction with Southern blot analyses, we found dup-mtDNAs in most of the examined tissues from both patients. The proportion of dup-mtDNA in these tissues was much lower than the proportion of delta-mtDNA, with one notable exception: in both patients, we found an unusually high level of dup-mtDNA in the heart. These data suggest that dup-mtDNAs may be more stable in heart tissue of KSS patients than in other long-lived postmitotic tissues.
Application of Skeletal Buttress Analogy in Composite Facial Reconstruction

Reconstructive algorithms for composite craniofacial defects have focused on soft tissue flaps with or without bone grafts. However, volumetric loss over time limits long-term preservation of facia...
Coda conditions and um infixation in Toba Batak

Abstract This paper examines the concatenative behaviour of the affix um in two varieties of Toba Batak and compares the Toba Batak case to its more familiar counterpart in Tagalog. Beyond the interest a comparison between Tagalog and Toba Batak holds for typology, the OT analysis proposed for Toba Batak contributes to the ongoing theoretical discussion of constraints and their evaluation. First, Toba Batak requires that several constraints be co-ranked. When constraints are co-ranked, their violations count equally in the evaluation of candidates, as though the co-ranked constraints inhabited the same cell of the OT tableau. Second, an OT analysis which captures the behaviour of the cognate morpheme um in both Tagalog and Toba Batak by simply re-ranking a few constraints compels an approach in which, for the cases examined, the work of NoCoda is performed by the combined activity of the two independently motivated constraints *Geminate and a CodaCond constraint targeting root nodes. The theoretical interest of this approach is that it suggests that NoCoda, the absolute suppression of phonological content in coda position, could be reconciled with a class of relativised CodaCond constraints, which individually result in the suppression of specific features or structural nodes.
Characterization of thermo-mechanical and long-term behaviors of multi-layered composite materials

Abstract This study presents characterization of thermo-mechanical viscoelastic behaviors of thick-section multi-layered fiber reinforced polymer (FRP) composite materials. The studied multi-layered systems follow viscoelastic behaviors of thermo-rheologically complex materials (TCM), which allow for stress and temperature variation with time. The multi-layered composites consist of alternating layers of unidirectional fiber (roving) and randomly oriented continuous filament mat (CFM). Isothermal creep-recovery tests at various stresses and temperatures are performed on axial, transverse, and 45° off-axis specimens having E-glass/vinylester and E-glass/polyester systems. Both tension and compression creep tests are conducted for 30 min followed by 10 min recovery. Analytical representation of a nonlinear single integral equation is applied to model the thermo-mechanical viscoelastic responses. Long-term material behaviors are then obtained through the vertical and horizontal shifting using analytical and graphical shifting procedures. The vertical and horizontal shift factors are associated with nonlinear stress and temperature dependent parameters. Linear extrapolation of transient creep compliance can be used to extend the material responses for longer times. The extended long-term (8–16 months) creep strains of the uniaxial specimens are verified with the long-term experimental data of Scott and Zureick [Compression creep of a pultruded E-glass/vinylester composite, Compos Sci Technol, 58 (1998) 1361–1369]. Finally, sensitivity analyses are conducted to examine the impact of error in material parameter characterizations to the overall long-term material behaviors.
Environmental influences on potential recruitment of Pink shrimp,Farfantepenaeus duorarum, from Florida Bay nursery grounds

Two modeling approaches were used to explore the basis for variation in recruitment of pink shrimp,Farfantepenaeus duorarum, to the Tortugas fishing grounds. Emphasis was on development and juvenile densities on the nursery grounds. An exploratory simulation modeling exercise demonstrated large year-to-year variations in recruitment contributions to the Tortugas pink shrimp fishery may occur on some nursery grounds, and production may differ considerably among nursery grounds within the same year, simply on the basis of differences in temperature and salinity. We used a growth and survival model to simulate cumulative harvests from a July-centered cohort of early-settlementstage postlarvae from two parts of Florida Bay (western Florida Bay and northcentral Florida Bay), using historic temperature and salinity data from these areas. Very large year-to-year differences in simulated cumulative harvests were found for recruits from Whipray Basin. Year-to-year differences in simulated harvests of recruits from Johnson Key Basin were much smaller. In a complementary activity, generalized linear and additive models and intermittent, historic density records were used to develop an uninterrupted multi-year time series of monthly density estimates for juvenile pink shrimp in the Johnson Key Basin. The developed data series was based on relationships of density with environmental variables. The strongest relationship was with sea-surface temperature. Three other environmental variables (rainfall, water level at Everglades National Park Well P35, and mean wind speed) also contributed significantly to explaining variation in juvenile densities. Results of the simulation model and two of the three statistical models yielded similar interannual patterns for Johnson Key Basin. While it is not possible to say that one result validates the other, the concordance of the annual patterns from the two models is supportive of both approaches.
Implementing middleware for content filtering and information flow control

This paper discusses the design and implementation of a middleware guard for purposes of content filtering and information flow control in the Multiple Independent Levels of Security (MILS) architecture. The MILS initiative is a joint research effort between academia, industry, and government to develop and implement a high assurance real-time architecture for embedded systems. The MILS architecture incorporates a separation kernel with formal system security policies that are evaluatable, non-bypassable, tamper-proof, and always invoked. Vendor specific high-level applications are assumed to be untrustworthy components; information flow control needs to be performed by middleware entities external to the applications.In the MILS architecture, a MILS Message Router and guards are placed between communicating entities to act as message content filters and enforce information flow control. As the MILS architecture does not restrict the protocols that can be employed for communications between applications, a distinct guard is needed for filtering messages within each protocol. Incorporating protocol specific guards in MILS embedded systems aids in the formal certification of those systems or the high-assurance safety critical formally-proven applications. The guards enable formally-proven security policies that guarantee information flow control, data isolation, predictable process control, damage limitation, and resource availability. An example is provided using a multi-level secure file server that uses a GIOP guard for fine-grained access control. The inclusion of a GIOP guard reduces the complexity and the effort necessary for system certification.
New model for estimating the thickness and permittivity of subsurface layers from GPR data

A new mathematical model for estimating the depth and permittivity of subsurface layers from measured ground-penetrating radar (GPR) data is presented. The new model considers the effects from the air-ground interface and introduces a ray-path-searching process in the depth calculation. It includes the conventional model as a special case. The experimental results agree well with the new model.
Blur into focus

Sir Morgan and Benton suggest that the human visual system does not have a general motion deblurring mechanism because the threshold for descriminating the spacing between two bars is degraded significantly by image motion. However, image motion has only modest effects when compared with static spatial blur.
Dopamine D1 receptor-agonist interactions: A mutagenesis and homology modeling study

The dopamine D1 receptor is a G protein-coupled receptor that regulates intracellular signaling via agonist activation. Although the number of solved GPCR X-ray structures has been steadily increasing, still no structure of the D1 receptor exists. We have used site-directed mutagenesis of 12 orthosteric vicinity residues of possible importance to G protein-coupled activation to examine the function of prototypical orthosteric D1 agonists and partial agonists. We find that residues from four different regions of the D1 receptor make significant contributions to agonist function. All compounds studied, which are catechol-amines, are found to interact with the previously identified residues: the conserved D103(3.32), as well as the trans-membrane V serine residues. Additional key interactions are found for trans-membrane VI residues F288(6.51), F289(6.52) and N292(6.55), as well as the extra-cellular loop residue L190(ECL2). Molecular dynamics simulations of a D1 homology model have been used to help put the ligand-residue interactions into context. Finally, we considered the rescaling of fold-shift data as a method to account for the change in the size of the mutated side-chain and found that this rescaling helps to relate the calculated ligand-residue energies with observed experimental fold-shifts.
Crystal structure of p50/p65 heterodimer of transcription factor NF-κB bound to DNA

The NF-kappaB p50/p65 heterodimer is the classical member of the Rel family of transcription factors which regulate diverse cellular functions such as immune response, cell growth, and development. Other mammalian Rel family members, including the proteins p52, proto-oncoprotein c-Rel, and RelB, all have amino-terminal Rel-homology regions (RHRs). The RHR is responsible for the dimerization, DNA binding and cytosolic localization of these proteins by virtue of complex formation with inhibitor kappaB proteins. Signal-induced removal of kappaB inhibitors allows translocation of dimers to the cell nucleus and transcriptional regulation of kappaB DNA-containing genes. NF-kappaB specifically recognizes kappaB DNA elements with a consensus sequence of 5'-GGGRNYYYCC-3' (R is an unspecified purine; Y is an unspecified pyrimidine; and N is any nucleotide). Here we report the crystal structure at 2.9 A resolution of the p50/p65 heterodimer bound to the kappaB DNA of the intronic enhancer of the immunoglobulin light-chain gene. Our structure reveals a 5-base-pair 5' subsite for p50, and a 4-base-pair 3' subsite for p65. This structure indicates why the p50/p65 heterodimer interface is stronger than that of either homodimer. A comparison of this structure with those of other Rel dimers reveals that both subunits adopt variable conformations in a DNA-sequence-dependent manner. Our results explain the different behaviour of the p50/p65 heterodimer with heterologous promoters.
Jitter in a Voronoi Pattern Media-Effect of Grain Size Distribution and Reader Width

We calculate jitter of the signal from transitions written on Voronoi-pattern media and played back with readers of varying widths. The expected dependence of jitter on reader width, as predicted by the microtrack model, is verified down to very narrow readers. Decrease in grain size variance results in less jitter. The original Voronoi patterns give a jitter value very close to the microtrack model. However, when the Voronoi patterns are modified such that grain size distribution is reduced, the jitter can be significantly smaller than in the microtrack model. This is due to the reduced randomness in the distribution of grain centers.