cssi/SciSciGPT-SciSciNet huggingface dataset:
The effects of immigrant concentration on changes in neighborhood crime rates

This study investigated the extent to which immigrant concentration is associated with reductions in neighborhood crime rates in the City of Los Angeles. A potential outcomes model using two-stage least squares regression was estimated, where immigrant concentration levels in 1990 were used as an instrumental variable to predict immigrant concentration levels in 2000. The instrumental variables design was used to reduce selection bias in estimating the effect of immigrant concentration on changes in official crime rates between 2000 and 2005 for census tracts in the City of Los Angeles, holding constant other demographic variables and area-level fixed effects. Non-parametric smoothers were also employed in a two-stage least squares regression model to control for the potential influence of heterogeneity in immigrant concentration on changes in crime rates. The results indicate that greater predicted concentrations of immigrants in neighborhoods are linked to significant reductions in crime. The results are robust to a number of different model specifications. The findings challenge traditional ecological perspectives that link immigrant settlement to higher rates of crime. Immigration settlement patterns appear to be associated with reducing the social burden of crime. Study conclusions are limited by the potential for omitted variables that may bias the observed relationship between immigrant concentration and neighborhood crime rates, and the use of only official crime data which may under report crimes committed against immigrants. Understanding whether immigrant concentration is an important dynamic of changing neighborhood patterns of crime outside Los Angeles will require replication with data from other U.S. cities.
Flume experiments on the origin of flaser bedding

A series of flume runs using a 12·5 h tidal cycle was conducted in order to determine whether or not flaser beds could be formed in nearshore subtidal areas as a result of purely tidal activity. The effects of clay composition, sand size, bed thickness, and maximum current velocity were investigated. The resistance to erosion of mud beds 10 mm thick or less is low; shear stresses approximately equal to those needed to initiate sand movement resulted in rapid erosion of the mud beds. In the light of the low resistance to erosion of the beds, and the necessity for increased thicknesses and very long time periods for their resistance to be increased substantially, it is concluded that the formation of these beds is unlikely to result from purely tidal action unless very large amounts of mud are available. A mechanism which more readily permits the deposition of thicker beds and longer consolidation times, such as storm action, is preferred.
Heat conduction of (111) Co/Cu superlattices

We report the observation of a large negative magnetothermal resistance in (111) Co/Cu superlattices grown by molecular beam epitaxy (MBE) techniques. The observed field dependence is proportional to that of the electrical resistance, in accordance with the Wiedemann–Franz law. The Lorentz number deduced from the measurements is (2.7±0.3)×10−8 V2/K2. The magnetothermopower also shows a similar correlation with resistivity. These findings reveal that large-angle elastic scattering of conduction electrons, arising from a spin-dependent density of states at the Fermi level, is the dominant process responsible for the observed large magnetotransport effects. In zero field, both electrons and phonons contribute to the thermal conduction of the MBE-grown Co/Cu system, at a ratio of about 1:2 near 300 K becoming nearly equal below 150 K.
Pressure broadening coefficients for rotational transitions of water in the 380– range

Abstract We present results of recent experiments on the pressure broadening of pure rotational transitions of H216O water in the 400– 600 cm −1 range by nitrogen and oxygen. The average broadening coefficient is about 0.056 cm −1 / atm for N2 and about 0.029 cm −1 / atm for O2, however, as expected, the broadening coefficient varies as a strong function of transition. In general, the broadening decreases with increasing J and Ka, with a stronger dependence on Ka than on J. On average, air broadening coefficients obtained from the coefficients presented here are about 10% lower than those found in HITRAN ’96, although, as detailed below, the differences are a function of quantum number.
Infrared spectrum of carbon trisulfide in solid argon.

Cocondensation of carbon disulfide with high-frequency discharged argon at 4 K produced carbon monosulfide and atomic sulfur, which reacted spontaneously upon annealing to form the carbon trisulfide molecule as identified from the multiplets observed in mixed 12C, 13C and 32S, 34S isotopic spectra. On the basis of isotopic substitution and theoretical frequency calculations, infrared absorptions at 1263.3 and 570.1 cm−1 were assigned to predominantly C═S stretching and bending vibrations of CS3 in solid argon. The CS3 molecule, which was calculated to have a singlet ground state with C2v symmetry, dissociated to form the weakly bound SCS−S complex upon visible light irradiation.
Hybrid log segmentation for assured damage assessment

A database log is the primary resource for damage assessment and recovery after an electronic attack. The log is a sequential file stored in the secondary storage and it can grow to humongous proportions in course of time. To make the process of damage assessment and recovery more efficient, segmenting the log based on different criteria has been proposed before. But the trade off is that, either segmenting the log involves a lot of computation or damage assessment is a complicated process. In this research we propose to strike a balance through hybrid log segmentation. Our method will reduce the time taken to perform damage assessment while still segmenting the log fast enough so that no intricate computation is necessary. We build our model from a log that was previously segmented based on number of transactions, a time window for transactions to commit or space occupied by committed transactions. While performing damage assessment, we re-segment the log based on transaction dependency. Thus during repeated damage assessment procedures, we create new segments with dependent transactions in them so that the process of damage assessment becomes faster when there are repeated attacks on the system. We have discussed various cases that are applicable and also presented algorithms for each of the cases discussed.
Cortisol Responsivity Differences in Children with Autism Spectrum Disorders During Free and Cooperative Play

Children with autism spectrum disorder (ASD) demonstrate significant heterogeneity in their profiles of social interaction and stress responsivity. We evaluated behavior and stress response in 52 male children ages 8–12 in a naturalistic playground interaction paradigm involving a child with ASD, a typically developing peer, and a same-age confederate. Younger children in the ASD group engaged in 5.8 times more approach behavior and showed a lower cortisol response than their older peers. Those that verbally initiated with their peers also showed a higher cortisol response. Older children with ASD exhibited the highest stress responsivity, while younger children with ASD showed more willingness to approach others without apparent stress. Intervening early and often may contribute to improvements in social engagement in youth with ASD.
Rates of intercage hopping in NaA studied by 129Xe inversion-recovery nuclear magnetic resonance experiments

Abstract The dynamics of xenon motion between the α-cages of zeolite NaA have been studied using 129 Xe nuclear magnetic resonance (NMR) inversion-recovery experiments. The apparent spin-lattice relaxation times suggest that the rate of intercage hopping decreases with loading. An upper limit for the intracrystalline diffusion of xenon in NaA is also calculated and is consistent with estimates made from other techniques.
Inhibition of breast cancer progression by an antibody to a thrombospondin-1 receptor

Background . Thrombospondin-1 (TSP-1) is a matrix-bound adhesive glycoprotein. Breast carcinoma cells exhibit increased expression of a novel TSP-1 receptor. We evaluated the role of this receptor in breast cancer adhesion and progression. Methods . Adhesion assays were performed to evaluate MDA-MB-231 breast cancer cell adhesion to TSP-1 in vitro in the presence of either nonimmune immunoglobulin G (IgG) or anti-TSP-1 receptor IgG. Receptor-mediated tumor cell progression was evaluated in athymic nude mice. Mice were inoculated with MDA-MB-231 breast cancer cells and randomized to treatment with intraperitoneal injections of saline solution, nonspecific IgG antibody, or an anti-TSP-1 receptor antibody every other day for 20 days. Mice were killed at 21 days. The peritoneal cavity was examined grossly for primary tumor implantation. The liver and lungs were examined histologically for micrometastases. Results . MDA-MB-231 breast cancer cells adhered to TSP-1 in vitro. This adhesion was inhibited to 10% of control by anti-TSP-1 receptor antibody (p Conclusions . These data suggest that TSP-1 and its receptor play an important role in breast cancer progression.
Charge reduced electrospray size spectrometry of mega- and gigadalton complexes: whole viruses and virus fragments.

The ability to analyze and identify large macromolecular complexes whose molecular weight is beyond the analyzable range of mass spectrometry is of great interest. The size of such complexes makes them suitable for analysis via mobility size spectrometry. In this work, charge reduced electrospray size spectrometry was used for the analysis of bacteriophage viruses with total molecular masses ranging from 3.6 MDa up to the gigadalton range. The electrospray source used was operated in “cone jet” mode with a mean droplet diameter of 170.56 nm. Bacteriophage MS2 was found to have a mobility diameter of 24.13 ± 0.06 nm and remain highly viable after the electrospray process. Larger bacteriophages T2 and T4 have lengths greater than the diameter of the electrospray jet and droplets; thus, they could not be completely enclosed and were found to fragment at the virus capsid head−tail noncovalent interface during either the jet formation or jet breakup process. No viable T2 or T4 virions were detectable after bei...
Doxorubicin-induced cardiac neurotoxicity: study with iodine 123-labeled metaiodobenzylguanidine scintigraphy.

Background Iodine 123-labeled metaiodobenzylguanidine (123I-MIBG) can be used to generate a scintigraphic image of the adrenergic nervous innervation of the heart.
Pathways in the hydrolysis of vertebrate rhodopsin

Abstract A direct method for measuring the amount of retinal 387 was used along with spectral techniques to measure each of the intermediates in the photolysis of rhodopsin and to unequivocally determine the pathways in solution extracts of bovine rhodopsin and excised toad and skate retinas. Metarhodopsin II 380 was the earliest intermediate which hydrolyzed to retinal 387 plus opsin. In excised toad retinas three approaches were used to show that Meta III 465 decayed directly to retinal 387 plus opsin. The only pathway consistent with the data was: Download full-size image In solution extracts the formation and hydrolysis of N -Retinylidene-Opsin was also observed.
Low‐Dimensional Representations of Special Linear Groups in Cross Characteristics

The low-dimensional projective irreducible representations in cross characteristics of the projective special linear group $\mbox{PSL}_{n}(q)$ are investigated. If $n \geq 3$ and $(n,q) \neq (3,2)$, $(3,4)$, $(4,2)$, $(4,3)$, all such representations of the first degree (which is $(q^{n}-q)/(q-1) - \kappa$ with $\kappa = 0$ or $1$) and the second degree (which is $(q^{n}-1)/(q-1)$) come from Weil representations. We show that the gap between the second and the third degree is roughly $q^{2n-4}$.
A Finite Element Study of the Combined Effect of Fusion and Disc Degeneration on Adjacent Levels of the Lumbar Spine

Intervertebral disc degeneration is believed to be the main cause of low back pain and has mostly been treated with lumbar interbody fusion or arthrodesis. Although fusion is a very common solution to low back pain it has been associated with disc degeneration and degenerative spondylolisthesis in the adjacent segment. A number of studies have been performed to study the effect of fusion, however there has not been any significant study to observe a fused spine with a degenerated disc at an adjacent level. This study involved a finite element model of the Lumbar spine L1-L5 which was fused with a bone graft at the L4-L5 level and degenerated in two stages at the L3-L4 level and also analyzed with reduced disc heights all in different cases.© 2003 ASME
Collaboration of the organization and implementation of studio design classes between teaching aids and professors in biomedical engineering

Studio based learning is a learning by discovery technique that allows for students to comprehend theories through lectures and test them in a hands-on environment during the same session. At New Jersey Institute of Technology (NJIT) Fundamentals of Engineering Design (BME FED-101) is an introductory course for freshmen which applies this method by emphasizing working in groups, communicating ideas, completing a project, and oral presentations- all necessary skills in today's competitive industry. The importance of teaching assistants (TA) has been recognized and been administered to provide incoming students a bridge with faculty and support as peer mentors. Initially, undergraduate teaching assistants are appointed traditional roles such as shadowing, assisting the professor and completing tasks, allowing for a healthy communication between the professor and the TAs and serving as a reliable feedback source. With guidance from faculty, the TAs begin to modify and build the course schedule and implement drastic changes to the curriculum such as the addition of MATLAB and Pro-Engineer (a prototype modeling software). Overall, the addition of undergraduate TAs to the FED course in the BME department at NJIT has been extremely successful, allowing the incoming students to gain valuable knowledge from their peers.
Lakatos' Proofs and Refutations Comes Alive in an Elementary Classroom.

This paper presents an alternative pedagogy implicit in Imre Lakatos’ Proofs and Refutations: The Logic of Mathematical Discovery. Through the voices of his characters, Lakatos reveals that learning mathematics is a discourse laden activity. In this approach it is acceptable, if not preferable, to refute a conjecture. Examples of the use of a Lakatosian approach in an elementary classroom are given. In this classroom setting students are able to propose more mature solutions, through posing and refuting conjectures.
Tunneling between two-dimensional electron gases

Abstract The current-voltage characteristics of AlAs-GaAs-AlAs heterostructures under hydrostatic pressures above 8 kbar have shown sharp negative differential resistance near zero bias. This result is understood in terms of tunneling through a GaAs potential barrier between two-dimensional electron gases formed in AlAs at the X point of the Brillouin zone.
Self-organized current transport through low-angle grain boundaries in YBa 2 Cu 3 O 7 − δ thin films studied magnetometrically

The critical current density flowing across low angle grain boundaries in ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ thin films has been studied magnetometrically. Films (200 nm thickness) were deposited on ${\mathrm{SrTiO}}_{3}$ bicrystal substrates containing a single [001] tilt boundary, with angles of 2, 3, 5, and 7 degrees, and the films were patterned into rings. Their magnetic moments were measured in applied magnetic fields up to 30 kOe at temperatures of 5\char21{}95 K; current densities of rings with or without grain boundaries were obtained from a modified critical state model. For rings containing 5 and 7 degree boundaries, the magnetic response depends strongly on the field history, which arises in large part from self-field effects acting on the grain boundary.
A “Time of Agric”: Rethinking the “Failure” of Agricultural Programs in 1970s Ghana

Summary Recent interest in a “new green revolution” in Africa has revived debate about state intervention in agricultural markets and biotechnology. These debates take for granted that the first wave of green revolution interventions in Africa failed to influence small-scale food farmers. This essay uses oral historical and documentary evidence from Ghana’s Northern Region to revisit the evidentiary basis of this assessment. Tracing how the production of aggregate data and changing interpretive frameworks in the 1970s and 1980s allowed policymakers to ignore the experiences of farmers, the essay advocates for the role of micro-historical analysis in assessing Africa’s recent agricultural past.
The Vital Importance of Critical Listening: An Extended Example

Abstract As a means of reinforcing the importance of critical listening, this study analyzes six speeches presented by President George W. Bush. These speeches provide an extended example of the use of a rhetorical technique, associational juxtaposition, in which President Bush gives the impression of a connection between Saddam Hussein's Iraq and the 9/11 attacks on the Pentagon and the World Trade Center by al-Qaeda when, in fact, no evidence or reasons existed to support such a connection. The paper concludes by discussing how Mr. Bush's use of associational juxtaposition underscores the need for effective critical listening.
The Cepheid Distance to NGC 0247

We report VRI CCD observations of nine Cepheids in the South Polar (Sculptor) Group spiral galaxy NGC 0247. Periods of these Cepheids range from 20 to 70 days. Over the past 20 years, the brightest Cepheid in our sample, NGC 0247:[MF09] C1, has decreased its period by 6%, faded by 0.8 mag in the V band, and become bluer by 0.23 mag in (V–I). A multiwavelength analysis of the Cepheid data yields a true distance modulus of μ o = 27.81 ± 0.10 mag (3.65 ± 0.17 Mpc) with a total line-of-sight reddening of E(V – I) = 0.07 ± 0.04 mag, after adopting an LMC true distance modulus of 18.5 mag and reddening of E(B – V) = 0.10 mag. These results are in excellent agreement with other very recently published (Cepheid and tip of the red giant branch) distances to NGC 0247. Combining both Cepheid data sets gives μ o = 27.85 ± 0.09 mag (3.72 ± 0.15 Mpc) with E(V – I) = 0.11 ± 0.03 mag.
Scarless Wound Healing

Scarring results from injuries and disease in mammalian adults and can cause pain and loss of function in the afflicted tissues. This negative aspect of wound repair is not always true for certain amphibians and during fetal development of mammals. Based on this knowledge, scientists and clinicians are investigating the mechanisms and growth factors that contribute to or deter a suitable environment for wound healing. This review summarizes these aspects and challenges for scarless repair.
Fighting the Cancer of Corruption and “Hostage-Taking” in the District Assemblies in Ghana

This article examines the increasing problem of corruption with its accompanying “hostage-taking” in the district assemblies, which are the core institutions in Ghana’s democratic decentralization ...
The Influence of Affect on the Achievement and Behavior of Students with Learning Disabilities

Research indicates that students with learning disabilities are likely to be at greater risk for experiencing negative affect than their higher achieving counterparts. The purpose of this article is to review recent research on the effects of affect on thoughts, cognition, and behavior. This research finds that induced positive affect leads to more accurate performance on math, greater learning of new vocabulary, and better performance on a new learning task. Implications of and suggestions for follow-up studies of negative and positive affect in students with learning disabilities are presented.
Clinical consequences of electrocardiographic artifact mimicking ventricular tachycardia

Electrocardiographic artifact can simulate ventricular tachycardia. The literature regarding electrocardiographic artifact is limited to case reports,1–7 proposed classifications,8,9 and diagnostic criteria.10 There is little information regarding the clinical implications of the misdiagnosis of artifact as ventricular tachycardia. We describe 12 patients who underwent unnecessary diagnostic or therapeutic interventions as a result of such a misdiagnosis. Methods We included in this series patients who were seen in consultation by a cardiac electrophysiologist at our institution between 1995 and 1999 and who underwent a diagnostic procedure or received treatment unnecessarily, solely as a result of the misdiagnosis of artifact as . . .
An investigation of four hypotheses concerning the order by which 4-year-old children learn the alphabet letters

Abstract This study tested four complementary hypotheses to characterize intrinsic and extrinsic influences on the order with which preschool children learn the names of individual alphabet letters. The hypotheses included: (a) own-name advantage , which states that children learn those letters earlier which occur in their own names, (b) the letter-order hypothesis , which states that letters occurring earlier in the alphabet string are learned before letters occurring later in the alphabet string, (c) the letter-name pronunciation effect , which states that children learn earlier those alphabet letters for which the name of the letter is in the letter's pronunciation, and (d) the consonant-order hypothesis , which states that children learn earlier those letters for which corresponding consonantal phonemes are learned early in phonological development. Participants were 339 four-year-old children attending public preschool classrooms serving primarily low-income children. Children's knowledge of each of the 26 alphabet letters was assessed, and these data were tested for the four hypotheses using a linear logistic test model (LLTM). Results from the LLTM confirmed all four hypotheses to show that the order of letter learning is not random, in that some letters hold an advantage over other letters to influence their order of learning. Implications for educational policy and practice are discussed.
Suddenly, all computing is parallel: seizing opportunity amid the clamor

The shift in computing hardware to parallel systems is well underway. Sequential chips are no longer designed, and the proud era of von Neumann architecture passes into history.Foundational change of this magnitude will disrupt traditional habits throughout the discipline, especially how students are to be introduced to and prepared for new challenges. But prepared how, and for what, exactly?With parallel programming models evolving, and a variety of approaches being tried in academia and industry, flexibility is vital. Customary time lags between research findings and classroom experience will have to be shortened, and industrial best practices find a new level of academic pertinence, quickening the pace of adoption for parallel education. In this talk, we'll look at some of these university/industry collaborations now underway.
SMN Is Essential for the Biogenesis of U7 Small Nuclear Ribonucleoprotein and 3′-End Formation of Histone mRNAs

Spinal muscular atrophy (SMA) is a neurodegenerative disease caused by a deficiency in the survival motor neuron (SMN) protein. SMN mediates the assembly of spliceosomal small nuclear ribonucleoproteins (snRNPs) and possibly other RNPs. Here, we investigated SMN requirement for the biogenesis and function of U7--an snRNP specialized in the 3'-end formation of replication-dependent histone mRNAs that normally are not polyadenylated. We show that SMN deficiency impairs U7 snRNP assembly and decreases U7 levels in mammalian cells. The SMN-dependent U7 reduction affects endonucleolytic cleavage of histone mRNAs leading to abnormal accumulation of 3'-extended and polyadenylated transcripts followed by downstream changes in histone gene expression. Importantly, SMN deficiency induces defects of histone mRNA 3'-end formation in both SMA mice and human patients. These findings demonstrate that SMN is essential for U7 biogenesis and histone mRNA processing in vivo and identify an additional RNA pathway disrupted in SMA.
The effect of constitutive CD8 expression on thymic selection; implications for the mechanism of CD4 and CD8 lineage commitment

The choice of an immature T cell to become a CD4 cell or a CD8 cell may be the result of instructive signals generated during positive selection. Alternatively, the initial commitment to a CD4 or CD8 lineage may be made independently of the specificity of the TCR. In this article, I describe our efforts to test the latter possibility using mice expressing a constitutive CD8 transgene. If lineage commitment is initially independent of MHC specificity, expression of ectopic CD8 in CD4 cells should allow CD4 cells with class I specific TCR to mature. We find that although some mature class I specific CD4 cells can be detected in CD8 transgenic mice, they are a minor population compared to class I selected CD8 cells. The implications of these results for the mechanism of lineage commitment are discussed.
The electron and energy transfer between oligothiophenes and thieno[3,4- b ]thiophene units

In a recent study, it has been shown that organic photovoltaic (OPV) solar cells consisting of polymers with certain stoichiometric ratios of alkyl thiophene:thieno[3,4- b ]thiophene monomeric units in random sequences, when combined with [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM), may have potentials for creating more efficient devices. Such a potential enhancement is mainly due to the light harvesting in most of the visible and near infrared region by these low band-gap polymers. However, very little is known about the photoinduced energy/electron transfer and transport within these copolymers. It is important to understand both the ultrafast interactions between these two monomeric units when they are linked in the copolymers and their interactions with the electron acceptor PCBM in order to determine the transport mechanisms in these systems, and then to create the architectures that optimize electronic transport properties. Therefore, three oligomer molecules have been synthesized to model the local interactions in the copolymers, each of which consists of a thieno[3,4- b ] thiophene derivative at its center linked with two alkyl oligothiophene side units. The alkyl oligothiophene units for the three molecules are 2, 4, or 8 units in length. By performing transient absorption and fluorescence upconversion measurements, the nature of the early exciton diffusion and energy transfer between these different units is elucidated.
Who returns for postpartum glucose screening following gestational diabetes mellitus

Objective The objective of the study was to determine the prevalence of postpartum impaired glucose regulation (IGR) and factors associated with glucose screening following gestational diabetes mellitus (GDM). Study Design This was a prospective cohort study of 707 women with GDM who delivered at the University Hospital (San Antonio, TX). Results A total of 35.5% of 400 women with any postpartum glucose testing had IGR postpartum, and 40.6% of 288 women who completed an oral glucose tolerance test had IGR, one-third of whom had isolated elevated 2-hour glucose levels. Women who failed to return for postpartum glucose testing (n = 307) were more likely to report prior GDM, have higher diagnostic glucose levels, and require insulin during pregnancy than women who returned for postpartum glucose testing. Conclusion Women who returned for postpartum glucose testing had less severe GDM than women who failed to return, suggesting that the true prevalence of postpartum IGR may be even higher than identified in our population.
Short, frequent words are more likely to appear genetically related by chance

An important question in historical linguistics is whether deep genetic relationships exist across language families. Although specific families can be reconstructed back to around 6,000 y ago, Pagel et al. (1) claim that seven Eurasian families arose from a common ancestor 15,000 y ago. Pagel et al. develop a phylogenetic model, starting with a subset of the Swadesh basic word list for seven language families in the Languages of the World Etymological Database, which lists reconstructed proto-words and cognates. Because these reconstructions are potentially unreliable, Pagel et al. treat each reconstructed cognate pair as a binary random variable. They find a robust correlation between the size of the cognate class and the word replacement rate (i.e., how fast the word is likely to be replaced in the vocabulary), which is closely related to frequency. As predicted, words with a slower replacement rate show deeper relationships across language families, which they take as evidence that there are deep relationships among the seven families.
Esophageal atresia and T.O.F. with stenosis of distal esophageal segment

This case report is the first preoperative documentation of the rare anomaly of stenosis of distal esophageal segment with T.O.F. It was confirmed at surgery. Brief review of the literature is reported as well.
Simultaneous confidence bands for nonlinear regression models

The maximization and minimization procedure for constructing confidence bands about general regression models is explained. Then, using an existing confidence region about the parameters of a nonlinear regression model and the maximization and minimization procedure, a generally conservative simultaneous confidence band is constructed about the model. Two examples are given, and some problems with the procedure are discussed
The Current Financial Crisis Its Origins, Its Impact, and the Needed Policy Response

It is now clear that the global economy is facing the worst economic and financial crisis since the Second World War. The crisis manifested itself initially in the subprime mortgage market in the US, but quickly spread to Europe; in the breakdown in the market for credit default swaps—a huge, unregulated and thoroughly opaque market; and in the general collapse of the markets for securitised instruments across the global financial system. It was aggravated, most analysts agree, by the initial policy missteps in handling the crisis, including in dealing with the problems at Lehman Brothers, which effectively froze the interbank market.This article discusses the origins, its impact as well as its policy implications of these developments. The article postulates that there were three basic root causes of the crisis: (a) the ‘search for yield’ and a weakening of—and lack of understanding of—risk management during the expansion phase of the credit cycle from 2002 to 2006; (b) the international fragmentation an...
Two‐dimensional array of rectangular slot antennas tuned with patch stubs for wide bandwidth and large scanning range

This paper presents a 2D array design composed of rectan- gular slot antennas tuned with patch stubs. The 2D array of 32 32 ele- ments for phased-array applications achieves a 38-dB gain, 60% imped- ance bandwidth, and 65° scanning angle without grating lobes. The return loss, radiation patterns, scanning capabilities, and gain are presented. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 149 -152, 2005; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/mop.20752
Temporal regulation of Salmonella virulence effector function by proteasome-dependent protein degradation

Salmonella enterica invasion of host cells requires the reversible activation of the Rho-family GTPases Cdc42 and Rac1 by the bacterially encoded GEF SopE and the GAP SptP, which exert their function at different times during infection and are delivered into host cells by a type III secretion system. We found that SopE and SptP are delivered in equivalent amounts early during infection. However, SopE is rapidly degraded through a proteosome-mediated pathway, while SptP exhibits much slower degradation kinetics. The half-lives of these effector proteins are determined by their secretion and translocation domains. Chimeric protein analysis indicated that delivery of SptP into host cells by the SopE secretion and translocation domain drastically shortened its half-life. Conversely, delivery of SopE by the SptP secretion and translocation signals significantly increased its half-life, resulting in persistent actin cytoskeleton rearrangements. This regulatory mechanism constitutes a remarkable example of a pathogen's adaptation to modulate cellular functions.
Indikation zur restorativen Rektumentfernung beim Karzinom — komplette vs. partielle und lokale Resektion

Veranderungen der chirurgischen Technik und ein neues Verstandnis der Tumorbiologie erlauben, auch Karzinome des unteren Rektumdrittels kontinenz-erhaltend zu operieren. Voraussetzung hierzu ist ein exaktes praoperatives Staging. Tumorlokalisation, Tumorstadium, Malignitatsgrad und Sphinkterfunktion bestimmen das operative Verfahren. Die komplette Entfernung des Mesorektums fuhrt zur Erhaltung des lateralen Sicherheitsabstandes. Der distale Sicherheitsabstand, dessen Bedeutung in den letzten Jahren relativiert wurde, wird durch intraoperative Schnellschnittuntersuchung gesichert. Als Kontraindikation zur restorativen Rektumentfernung gilt die Infiltration des Sphinkterapparates. Bei praoperativ eingeschrankter Kontinenz fuhrt die restorative Rektumentfernung zu einer Verschlechterung der Kontinenzsituation. Das wesentliche Problem stellt die Verhinderung des Lokalrezidivs dar. Wahrend die komplette Resektion durch die Exstirpation des Mesorektums grostmogliche Sicherheit erreicht, stellen distale Tumorsatellitenknoten im Mesorektum bei partiellen Resektionen ein Risiko dar. Die Lokalexzision von Rektumkarzinomen kann bei T1-Tumoren der Differenzierungsgrade G1 und G2 und korrekter Technik vergleichbare Ergebnisse liefern.
Optimal cross-layer wireless control policies using TD learning

We present an on-line crosslayer control technique to obtain policies for wireless networks. Our approach combines network utility maximization and adaptive modulation over an infinite discrete-time horizon using a class of performance measures we call ime smoothed utility functions. We model the system as an average-cost Markov decision problem. Model approximations are used to find suitable basis functions for application of least squares TD-learning techniques. The approach yields network control policies that learn the underlying characteristics of the random wireless channel and that approximately optimize network performance.
Correction to "Boundary single-layer routing with movable terminals"

In boundary single-layer routing with slidable or permutable terminals (BSLR-S or BSLR-P), the assumption that each net may have more than one terminal in a range or cluster should be removed. An example that shows Pick-Closest might report "unsolvable" for a solvable instance is considered. It is clear that the instance is solvable if (and only if) the two terminals of net N/sub 1/ are assigned to vertices c and d. However, Pick-Closest will assign the two terminals of net N/sub 1/ to vertices /spl lcub/b,c/spl rcub/ or /spl lcub/d,e/spl rcub/, then report "unsolvable" due to the failure in routing net N/sub 2/. Thus, Pick-Closest only works in instances when each net has at most one terminal in a range. Since BSLR-P also includes slidable terminals, we employ Pick-Closest to solve BSLR-P when TR-permutation is determined by Greedy-Assignment. Thus in BSLR-P, each net can have at most one terminal in a cluster as well. The time complexity of the problem of boundary single-layer routing with slidable and permutable terminals remains open if a net is allowed to have multiple terminals in a cluster. >
Elastic Properties of Solid 4He Monolayers from 4.2°K Vapor Pressure Studies

Heat capacity studies of monolayer 4He on exfoliated graphite have revealed a striking variety of surface-phase equilibria.1–4 In some cases the thermal behavior of these thin films has led to a direct comparison with the properties of the bulk. One of the most intriguing observations has been the near identity of the Debye temperatures at the same interatomic separation in the respective solid phases. This apparent coincidence has motivated the present study of those mechanical properties that determine the Debye θ at low temperature. In particular, how are the elastic constants for submonolayer solid helium related to those of the bulk? This question seems fundamental for eventual understanding of why the composite thermal behavior is analogous in two and three dimensions.
Combined Haploinsufficiency for ATM and RAD9 as a Factor in Cell Transformation, Apoptosis, and DNA Lesion Repair Dynamics

Loss of function of oncogenes, tumor suppressor genes and DNA damage processing genes has been implicated in the development of many types of cancer, but for the vast majority of cases, there is no link to specific germ line mutations. In the last several years, heterozygosity leading to haploinsufficiency for proteins involved in DNA repair pathways was shown to play a role in genomic instability and carcinogenesis after DNA damage is induced. Because the effect of haploinsufficiency for one protein is relatively small, we hypothesize that predisposition to cancer could be a result of the additive effect of heterozygosity for two or more genes, critical for pathways that control DNA damage signaling, repair or apoptosis. To address this issue, primary mouse cells, haploinsufficient for one or two proteins, ATM and RAD9, related to the cellular response to DNA damage were examined. The results show that cells having low levels of both ATM and RAD9 proteins are more sensitive to transformation by radiation, have different DNA double-strand break repair dynamics and are less apoptotic when compared with wild-type controls or those cells haploinsufficient for only one of these proteins. Our conclusions are that under stress conditions, the efficiency and capacity for DNA repair mediated by the ATM/RAD9 cell signaling network depend on the abundance of both proteins and that, in general, DNA repair network efficiencies are genotype-dependent and can vary within a specific range.
The Influence of Base Identity and Base Pairing on the Function of the α-Sarcin Loop of 23S rRNA

The alpha-sarcin loop of large subunit rRNAs is one of the sites of interaction of elongation factors with the ribosome, and the target of the cytotoxins alpha-sarcin and ricin. Using a genetic selection for increased frameshifting in a reporter gene, we have isolated a C --> U mutation at position 2666 in the alpha-sarcin loop. In the NMR-derived structure of the loop, bases equivalent to 2666 and 2654 are paired via a non-canonical base pairing interaction. Each of the three base substitutions at C2666 and A2654 was constructed by site-directed mutagenesis of a plasmid borne copy of the rrnB operon of Escherichia coli. Only the C2666 --> U and A2654 --> G mutations that resulted in the formation of canonical A-U and C-G base pairs respectively, increased the levels of stop codon readthrough and frameshifting. The effects of different base pair combinations at positions 2666 and 2654 on ribosome function were then tested by constructing and analyzing all possible base combinations at these sites. All A --> G base substitution mutations at position 2654 and C --> U substitutions at position 2666 increased the levels of translational errors. However, these effects were greatest when G2654 and U2666 had the potential to engage in standard Watson-Crick base pairing interactions. These data indicate that base identity as well as base pairing interactions are important for the function of this essential component of the large subunit rRNA.
Ethanol attenuation of long-term depression in the nucleus accumbens can be overcome by activation of TRPV1 receptors

Background Altered expression of synaptic plasticity within the nucleus accumbens (NAc) constitutes a critical neuroadaptive response to ethanol (EtOH) and other drugs of abuse. We have previously reported that N-methyl-D-aspartate receptor (NMDAR)-dependent long-term depression (LTD) is markedly affected by chronic intermittent ethanol exposure in vivo; however, endocannabinoid (eCB)-dependent synaptic depression, despite being very well-documented in the dorsal striatum, is much less well understood in the NAc. Methods Whole cell patch clamp electrophysiology was used to investigate interactions between these different plasticity-induction systems. Excitatory postsynaptic currents (EPSCs) were measured in the NAc shell and NMDAR-LTD was induced by a pairing protocol (500 stimuli at 1 Hz stimulation [low-frequency stimulation (LFS)] paired with postsynaptic depolarization to −50 mV). AM251, a CB1 receptor antagonist, was used to determine whether this form of LTD is modulated by eCBs. To determine the effect of EtOH on a purely eCB-dependent response in the NAc, depolarization-induced suppression of excitation (DSE) was used in the presence of 40 mM EtOH. Finally, we determined whether the enhancement of eCB signaling with URB597, a fatty acid amide hydrolase inhibitor, and AM404, an anandamide re-uptake inhibitor would also modulate LFS LTD in the presence of NMDAR blockade or EtOH. Results In the presence of AM251, the LFS pairing protocol resulted in NMDAR-dependent long-term potentiation that was blocked with either EtOH or DL-APV. We also found that DSE in the NAc shell was blocked by AM251 and suppressed by EtOH. Enhanced eCB signaling rescued NAc-LTD expression in the presence of EtOH through a distinct mechanism requiring activation of TRPV1 receptors. Conclusions EtOH modulation of synaptic plasticity in the NAc is dependent upon a complex interplay between NMDARs, eCBs, and TRPV1 receptors. These findings demonstrate a novel form of TRPV1-dependent LTD in the NAc shell that may be critical for EtOH dependence.
Droplet transport on flat chemically heterogeneous surfaces via periodic wetting barriers and vibration

We report on a Flat Surface Ratchet, capable of achieving droplet transport using curved hydrophilic rungs patterned onto a hydrophobic surface. These periodic asymmetric wetting barriers can be fabricated easily on a wide variety of surfaces. Transport of a 10 µl droplet is achieved by an electromagnetic speaker with vertical sinusoidal vibrational amplitudes as low as 37 µm at 82 Hz, making this technology implementable for a wide range of discrete microfluidic applications.
Advanced Hypertensive Heart Disease in Spontaneously Hypertensive Rats Lisinopril-Mediated Regression of Myocardial Fibrosis

Left ventricular hypertrophy (LVH) in spontaneously hypertensive rats (SHR) is accompanied by a structural remodeling of the myocardium that includes myocyte hypertrophy and interstitial and perivascular fibrosis of intramyocardial coronary arteries. The structural abnormalities related to fibrous tissue accumulation lead to increased myocardial diastolic stiffness and ultimately impaired systolic function of the left ventricle. It has been shown in 14-week-old SHR with early hypertensive heart disease that myocardial fibrosis could be reversed and myocardial diastolic stiffness normalized by 12-week treatment with the angiotensin-converting enzyme inhibitor lisinopril. Whether such functional defects of the myocardium, based on adverse structural changes, are also reversible in advanced hypertensive heart disease has been questioned. Therefore, we treated 78-week-old male SHR that had chronic hypertension and advanced LVH with severe myocardial fibrosis and age- and sex-matched normotensive Wistar-Kyoto rats (WKY) with 20 mg/kg per day oral lisinopril for 8 months. Compared with untreated SHR or WKY, we found the following: (1) Systolic arterial pressure was normalized ( P P P P P 14 C]collagen with myocardial tissue extracts after trypsin activation of myocardial promatrix metalloproteinase 1; matrix metalloproteinase 1 activity remained unchanged in WKY treated with lisinopril; and (4) systolic dysfunction, measured by a significantly ( P
9/11-Related Experiences and Tasks of Landfill and Barge Workers: Qualitative Analysis from the World Trade Center Health Registry

Few studies have documented the experiences of individuals who participated in the recovery and cleanup efforts at the World Trade Center Recovery Operation at Fresh Kills Landfill, on debris loading piers, and on transport barges after the September 11, 2001 terrorist attack. Semi-structured telephone interviews were conducted with a purposive sample of workers and volunteers from the World Trade Center Health Registry. Qualitative methods were used to analyze the narratives. Twenty workers and volunteers were interviewed. They described the transport of debris to the Landfill via barges, the tasks and responsibilities associated with their post-9/11 work at the Landfill, and their reflections on their post-9/11 experiences. Tasks included sorting through debris, recovering human remains, searching for evidence from the terrorist attacks, and providing food and counseling services. Exposures mentioned included dust, fumes, and odors. Eight years after the World Trade Center disaster, workers expressed frustration about poor risk communication during recovery and cleanup work. Though proud of their contributions in the months after 9/11, some participants were concerned about long-term health outcomes. This qualitative study provided unique insight into the experiences, exposures, and concerns of understudied groups of 9/11 recovery and cleanup workers. The findings are being used to inform the development of subsequent World Trade Center Health Registry exposure and health assessments.
Performance Evaluation of Thermal Desorption System (TDS) for Detection of Basic Drugs in Forensic Samples by GC-MS

Stir bar sorptive extraction is an innovative sample extraction technique that can be used to process blood, urine, and tissue samples for routine drug screening in the forensic toxicology laboratory. The Gerstel Twister™ desorption unit (TDU) system is a multifunctional desorption unit capable of determining the presence of analytes from liquid samples after extraction using the Twister stir bar. The TDU desorption system was evaluated for use in combination with gas chromatography-mass spectrometry (GC-MS) for determining the presence of basic drugs in forensic samples. Human blood fortified with known quantities of drugs was used to evaluate sample diluents, extraction time, injection parameters and recovery. Case specimens containing drugs typically encountered in forensic samples were evaluated using the desorption method and compared with a liquid-liquid extraction method followed by GC-MS analysis. This evaluation demonstrated that the TDU desorptive method worked equally as well as the routine extraction method for the detection of basic drugs in screening forensic samples. In addition, the described technique avoids the use of extraction solvents and the subsequent centrifugation, transfer, and concentration steps required of liquid-liquid and solid-phase extraction methods.
Chest Pain in Young Patients in an Office Setting: Cardiac Diagnoses, Outcomes, and Test Burden

This study determined the incidence of cardiac diagnoses demonstrably related to chest pain in young patients and determined whether those with exertional chest pain were more likely to have a cardiac diagnosis. It evaluated the course of patients with chest pain after pediatric cardiology evaluation regarding interventions, outcomes, and additional test burden. This was a retrospective study of 203 patients with an office pediatric cardiology assessment of chest pain from January 2000 through December 2004. Fifteen patients (7.4%) had cardiac diagnoses, 5 (2.5%) had cardiac diagnoses demonstrably related to their chest pain complaints (arrhythmias, mitral valve prolapse), and none had ischemia. Exertional chest pain, in this study, did not increase the risk of having a cardiac diagnosis. Following evaluation, 80% of patients did not return for complaints of chest pain. Ten percent had 2 or more additional visits to any medical site for chest pain but no additional cardiac diagnoses were found.