cssi/SciSciGPT-SciSciNet huggingface dataset:
Longer Operative Time Is Independently Associated With Surgical Site Infection and Wound Dehiscence Following Open Reduction and Internal Fixation of the Ankle

Background: Little is known regarding the association of operative time with adverse events following foot and ankle surgery. This study tests whether greater operative time is associated with the ...
2,7-Diaminomitosene, a Monofunctional Mitomycin-C Derivative, Alkylates DNA in the Major Groove - Structure and Base-Sequence Specificity of the DNA Adduct and Mechanism of the Alkylation

Reductive activation of the bifunctional alkylator and DNA cross-linking agent mitomycin C (MC) yields 2,7-diaminomitosene (2,7-DAM) as the major product of its activation both in cell-free systems and in vivo. 2,7-DAM lacks one of the alkylating functions of MC, the aziridine. We show that 2,7-DAM itself alkylates DNA monofunctionally upon reductive activation, to form a heat-labile adduct. A guanine-N7−2,7-DAM adduct was isolated from the drug−DNA complex upon heating. Nuclease digestion yielded this adduct both in the nucleoside (dG-2,7-DAM) and dinucleoside phosphate [d(GpG)-2,7-DAM] forms. The structures of all three forms were determined by LC−ESIMS and differential UV spectroscopy. The adduct is sequence-specific to guanines in (G)n tracts of DNA. A guanine-N7−2,7-DAM adduct in DNA was indirectly observed previously by Prakash et al. (Prakash, A. S.; Beall, H.; Ross, D.; Gibson, N. W. Biochemistry 1993, 32, 5518−5525). The results indicate that selective removal of the aziridine function of MC resu...
Target Population Statistical Inference With Data Integration Across Multiple Sources—An Approach to Mitigate Information Shortage in Rare Disease Clinical Trials

A major challenge for rare disease clinical trials is the limited amount of available information for making robust statistical inference. While external data present information integration opport...
Triode-mode Envelope Detectors for Near Zero Power Wake-up Receivers

This work presents an envelope detector topology based upon triode mode transistors operating as a chain of charge pumps. This detector offers superior tunability, performance, and robustness over the Dickson topology. This work utilizes a direct gate bias applied to complementary devices to form a single detector stage. Application of the RF signal directly onto the transistor source node allows for an independent gate bias. The source only injection reduces the total input capacitance of the detector device thereby reducing total input capacitance. This direct gate bias allows strong control over the device channel impedance (R D ) which directly modulates the detector input impedance, output noise level and charge time.
A Rare Case of Hypokalemic Ventricular Tachycardia in a Patient With Thyrotoxic Periodic Paralysis

Thyrotoxic periodic paralysis (TPP) is a potentially fatal complication of hyperthyroidism, characterized by recurrent muscle paralysis and hypokalemia. We present a case of a 32-year-old apparently healthy male patient, who presented with acute paraparesis associated with hypokalemia (K: 1.6 mmol/L), complicated by ventricular tachycardia (VT). Advanced cardiac life support was initiated with an amiodarone infusion, and eventually QRS complex narrowed and wide complex tachycardia resolved. Intravenous potassium chloride (KCl) 40 mEq over 2-3 h and oral KCL 40 mEq were administered to treat the electrolyte imbalance. Patient paralysis was quickly reversed; motor function was regained with movement of the lower extremities. This case highlights the importance of early recognition and prompt treatment of TPP as a differential diagnosis for muscle weakness, especially in the setting of severe hypokalemia. It is important to pay attention to the possibility of the development of lethal VT associated with hypokalemia in the setting of hyperthyroidism and thyrotoxic paralysis.
Developing a model of empathy for public administration

Empathy is often cited within the public administration literature, yet its uses are isolated, incidental and frequently in conflict. Like many other academic and applied fields before it, public a...
Causal Inference in Microbiomes Using Intervention Calculus

Inferring causal effects is critically important in biomedical research as it allows us to move from the typical paradigm of associational studies to causal inference, and can impact treatments and therapeutics. Association patterns can be coincidental and may lead to wrong inferences in complex systems. Microbiomes are highly complex, diverse, and dynamic environments. Microbes are key players in health and diseases. Hence knowledge of genuine causal relationships among the entities in a microbiome, and the impact of internal and external factors on microbial abundance and interactions are essential for understanding disease mechanisms and making treatment recommendations. In this paper, we investigate fundamental causal inference techniques to measure the causal effects of various entities in a microbiome. In particular, we show how to use these techniques on microbiome datasets to study the rise and impact of antibiotic-resistance in microbiomes. Our main contributions include the following. We introduce a novel pipeline for microbiome studies, new ideas for experimental design under weaker assumptions, and data augmentation by context embedding. Our pipeline is robust, different from traditional approaches, and able to predict interventional effects without any controlled experiments. Our work shows the advantages of causal inference in identifying potential pathogenic, beneficial, and antibiotic-resistant bacteria. We validate our results using results that were previously published.
"Chinese Journal of Endemiology" between 2005 and 2009: a comprehensive quality analysis

Objective To evaluate the academic status and influence of "Chinese Journal of Endemiology" in the preventive medicinal core periodicals to provide a scientific basis for further improving the quality of the journal. Methods Journal evaluation data of "Chinese Science and Technology Journal Citation Reports" (2005 -2009 periodicals) as a statistical source, twenty-eight core journals of preventive medicine as an evaluation object, a single evaluation index (such as impact factor, total cites and he cited rate) as a reference, integrated 15 journal evaluation indicators of 28 kinds of preventive medicinial core periodicals into 4 comprehensive evaluation indexes.Calculate the composite indicator score through principal component analysis method if the index's relevant eigenvalue was greater than 1 and their cumulative contribution rate was more than 80%. Then calculated the composite indicator scores of the 4 kinds of indexes, which were weighted into linear combination of the composition with its corresponding contribution. Assess the overall level and the academic quality of "Chinese Journal of Endemiology" among core journals of preventive medicine on the basis of the 4 composite score. Results Impact factors of Chinese Journal of Endemiology were 0.909, 1.237, 0.899, 0.832, 1.019 between 2005 and 2009, ranked number 4, 1, 4, 6 and 3 among the 28 core journals. Its total cited frequency respectively were 933, 1172,1101, 1267 and 1491, among the 28 kinds of core journals and ranked number 4, 4, 6, 5 and 6. Comprehensive score of "Chinese Journal of Endemiology" were 0.269, 0.371, 0.282, 0.247 and 0.602, and its rank were 7th, 5th,7th,5th and 4th in the 28 core journals. Conclusions The impact factor and citation frequency of "Chinese Journal of Endemiology" are ranked at the forefront of preventive medicinal core periodicals. More attention should be paid to academic exchanges of related areas, and to enhance the academic quality of the journal. Key words: Journal; Impact factor; Total citations; Principal component analysis; Outcome assessment
For Love and Money? Earnings and Marriage Among Same-Sex Couples

We investigate the earnings effects of marriage among same-sex couples in the United States. Gays and lesbians in the United States have only recently been allowed to enter into legally recognized marriages. As such, we know little about the impact of same-sex marriage on the economic lives of gays and lesbians. We use data from the 2013 to 2017 American Community Survey to show that married gay men experience a 3% marriage earnings premium and lesbian women experience a 6% marriage earnings premium relative to their unmarried cohabiting counterparts. The marriage premium for gay men is smaller than that of heterosexual married men, but the lesbian marriage premium is similar in size to the premium for heterosexual women. In both cases, we show that the marriage premium is larger relative to single gay men and lesbian women in the 2013 to 2017 National Health Interview Surveys. We also find that the marriage premium is more than two times larger among individuals who earn more than their partners, and marriage increases intrahousehold differences in labor market outcomes. This pattern is consistent with a common explanation of the earnings premium experienced by heterosexual men and women: marriage increases investments in relationships that affect patterns of household specialization. Therefore, our results suggest that the effect of marriage on how households organize their time is general and not unique to different-sex households.
Eye Movement Desensitization and Processing (EMDR)

EMDR was originally developed to address traumatic memories. In teaching patients who have had a traumatic experience to repetitively move their eyes in a conjugate manner while contemplating that memory, EMDR therapy attempts to copy the conjugate eye movements occurring in rapid eye movement sleep (REMS). EMDR was consciously based on the theoretically proposed role for REMS in emotional processing during sleep, particularly in the case of negative emotions and trauma. Unfortunately for this theoretical construct, despite intensive research, no clear evidence has been discovered suggesting that the processing of emotional memories is confined to REMS. However, from the very first, remarkable results have been obtained using EMDR to treat patients diagnosed with PTSD. EMDR therapy consistently demonstrates large effects in treating subjective distress and moderate effects in treating PTSD and depression. There are a plethora of trained therapists, and since EMDR is non-aversive and not known to induce negative side effects, it is apparently ideal for use in at-risk populations. EMDR is equally effective to prolonged exposure when used immediately post-trauma. More studies document the effectiveness of EMDR therapy in treating PTSD than support any other form of PTSD therapy. A typical EMDR treatment protocol is described.
Rectal and Anal Cancer

Rectal adenocarcinoma and anal canal squamous cell cancer represent two distinct diseases that arise from the distal gastrointestinal tract and utilize radiation concurrent with chemotherapy as a component of care for localized presentations. While chemoradiation is administered preoperatively for rectal cancer, and as definitive treatment for anal cancer, localized management decisions and determination of prognosis are currently based on the assessment of clinical stage. For these cancers, the role of imaging to guide radiotherapy is critical and further investigation into the identification of biomarkers and other predictors for individualized patient care is warranted.
THE RELATIONSHIP BETWEEN SINGLE LEG BALANCE AND ISOMETRIC ANKLE AND HIP STRENGTH IN A HEALTHY POPULATION.

Background Impaired balance and strength commonly affect athletes with conditions like chronic ankle instability (CAI). Yet, clinical research surrounding the relationship between balance, strength, and CAI is still growing. Deeper investigation of these relationships is warranted to better inform clinical practice patterns when managing athletes with balance deficits. Purpose To investigate the relationship between single leg balance, ankle strength, and hip strength in healthy, active adults. Study Design Observational study. Methods Forty healthy participants (age 23.7 ± 4.9 years) were assessed for static balance, using a modified version of the Balance Error Scoring System (mBESS), as well as isometric strength of ankle and hip musculature via handheld dynamometry. Pearson's correlations were used to analyze relationships between balance and strength measures. Paired t-tests were utilized to compare dominant and non-dominant limb performance. Results Negligible to low, negative correlations were found between balance scores and hip extension strength (r = -0.24 to -0.38, p<0.05). High, positive correlations were found between ankle and hip strength measures (r = 0.75 to 0.84, p<0.05). When comparing dominant to non-dominant limbs, only minimal differences were noted in ankle eversion strength (mean difference = 6.0%, p<0.01) and hip extension strength (mean difference = 5.5%, p<0.01). Conclusions Minimal relationships were identified between static balance and isometric ankle and hip strength. Comparison of dominant and non-dominant limbs suggests that clinicians should expect relative symmetry in balance and strength in healthy adults. Thus, asymmetries found during clinical examination should raise suspicion of specific impairments that may lead to dysfunction. Level of Evidence 2c.
Quantum correlation interferometry in reflection: Application to the quantum–classical transition, decoherence, and indirect measurement

Abstract A many-body interferometer is described in which all of its components are treated as quantum objects. It consists of particles reflecting elastically from a “mirror”. Quantum correlation is a consequence of conservation of energy and momentum while interference occurs when the order in which the non-local particles reflect is indeterminate. The resulting superposition exhibits correlated interference with diverse characteristics depending on the structure of the many-body wavegroup. Two non-local microscopic particles reflecting from a mesoscopic “mirror” illustrate unique features of this correlation interferometer. The microscopic momentum exchanged then results in small displacements of the superposed mesoscopic mirror substates, which mitigates experimental difficulties in determining the quantum–classical boundary. Quantum behavior of this mesoscopic mirror, evident in indirect measurements involving correlations between only the reflecting microscopic particles, disappears for a classical mirror which cannot exist in such superposition states.
Imagining Localism in Post-Conflict Syria: Prefigurative Reconstruction Plans and the Clash Between Liberal Epistemology and Illiberal Conflict

The liberal epistemology of prefigurative post-conflict reconstruction plans for Syria sits in tension with the messiness and materiality of Syria's illiberal conflict ontology. I argue that this t...
Correction to: Abstract rules for complex systems

The original version of this article unfortunately contained a mistake. The name of corresponding author Mario Mario Rizzo was incorrect. The correct name should be Mario J. Rizzo.
Proteasome stress in skeletal muscle mounts a long-range protective response that delays retinal and brain aging

Neurodegeneration in the central nervous system (CNS) is a defining feature of organismal aging that is influenced by peripheral tissues. Clinical observations indicate that skeletal muscle influences CNS aging, but the underlying muscle-to-brain signaling remains unexplored. In Drosophila, we find that moderate perturbation of the proteasome in skeletal muscle induces compensatory preservation of CNS proteostasis during aging. Such long-range stress signaling depends on muscle-secreted Amyrel amylase. Mimicking stress-induced Amyrel upregulation in muscle reduces age-related accumulation of poly-ubiquitinated proteins in the brain and retina via chaperones. Preservation of proteostasis stems from the disaccharide maltose, which is produced via Amyrel amylase activity. Correspondingly, RNAi for SLC45 maltose transporters reduces expression of Amyrel-induced chaperones and worsens brain proteostasis during aging. Moreover, maltose preserves proteostasis and neuronal activity in human brain organoids challenged by thermal stress. Thus, proteasome stress in skeletal muscle hinders retinal and brain aging by mounting an adaptive response via amylase/maltose.
On whose land do I/we learn? Rethinking ownership and land acknowledgment

In our semester original teaching idea, we detail possibilities of resistance to the neoliberal university by considering tribal critical race theory and postsocialist feminism as frames for decolo...
SU-E-P-31: Quantifying the Amount of Missing Tissue in a Digital Breast Tomosynthesis

Purpose: To automatically quantify the amount of missing tissue in a digital breast tomosynthesis system using four stair-stepped chest wall missing tissue gauges in the Tomophan™ from the Phantom Laboratory and image processing from Image Owl. Methods: The Tomophan™ phantom incorporates four stair-stepped missing tissue gauges by the chest wall, allowing measurement of missing chest wall in two different locations along the chest wall at two different heights. Each of the four gauges has 12 steps in 0.5 mm increments rising from the chest wall. An image processing algorithm was developed by Image Owl that first finds the two slices containing the steps then finds the signal through the highest step in all four gauges. Using the signal drop at the beginning of each gauge the distance to the end of the image gives the length of the missing tissue gauge in millimeters. Results: The Tomophan™ was imaged in digital breast tomosynthesis (DBT) systems from various vendors resulting in 46 cases used for testing. The results showed that on average 1.9 mm of 6 mm of the gauges are visible. A small focus group was asked to count the number of visible steps for each case which resulted in a good agreement between observer counts and computed data. Conclusion: First, the results indicate that the amount of missing chest wall can differ between vendors. Secondly it was shown that an automated method to estimate the amount of missing chest wall gauges agreed well with observer assessments. This finding indicates that consistency testing may be simplified using the Tomophan™ phantom and analysis by an automated image processing named Tomo QA. In general the reason for missing chest wall may be due to a function of the beam profile at the chest wall as DBT projects through the angular sampling. Research supported by Image Owl, Inc., The Phantom Laboratory, Inc. and Raforninn ehf; Mallozzi and Healy employed by The Phantom Laboratory, Inc.; Goodenough is a consultant to The Phantom Laboratory, Inc.; Fredriksson, Kristbjornsson, Olafsson, Oskarsdottir and Olafsdottir are employed by Raforninn, Ehf
Type casting verification: stopping an emerging attack vector

Many applications such as the Chrome and Firefox browsers are largely implemented in C++ for its performance and modularity. Type casting, which converts one type of an object to another, plays an essential role in enabling polymorphism in C++ because it allows a program to utilize certain general or specific implementations in the class hierarchies. However, if not correctly used, it may return unsafe and incorrectly casted values, leading to so-called bad-casting or type-confusion vulnerabilities. Since a bad-casted pointer violates a programmer's intended pointer semantics and enables an attacker to corrupt memory, bad-casting has critical security implications similar to those of other memory corruption vulnerabilities. Despite the increasing number of bad-casting vulnerabilities, the bad-casting detection problem has not been addressed by the security community. In this paper, we present CAVER, a runtime bad-casting detection tool. It performs program instrumentation at compile time and uses a new runtime type tracing mechanism--the type hierarchy table--to overcome the limitation of existing approaches and efficiently verify type casting dynamically. In particular, CAVER can be easily and automatically adopted to target applications, achieves broader detection coverage, and incurs reasonable runtime overhead. We have applied CAVER to large-scale software including Chrome and Firefox browsers, and discovered 11 previously unknown security vulnerabilities: nine in GNU libstdc++ and two in Firefox, all of which have been confirmed and subsequently fixed by vendors. Our evaluation showed that CAVER imposes up to 7.6% and 64.6% overhead for performance-intensive benchmarks on the Chromium and Firefox browsers, respectively.
Ugly in a world where you can choose to be beautiful: teaching and learning about diversity via virtual worlds

In this paper, we discuss an approach to providing students with first-hand learning experiences that help them understand cultural differences and aspects of diversity. As part of a five-week course, fourteen high school students participated in activities within massively multiplayer online games (MMOGs) as learning environments to explore issues of identity construction, discrimination, and cultural sensitivity. Student attitudes towards diversity and towards the technology used in the course are discussed. The students reported using the tool to explore and to equalize cultural and demographic differences. They showed significant improvement on a measure of sensitivity towards an understanding of diversity, and evidence suggests they were able to develop a more sophisticated, less essentialist model of diversity.
Fusion of cells by flipped SNAREs

The SNARE (soluble N-ethylmaleimide–sensitive factor attachment protein receptor) hypothesis suggests that pairs of proteins known as vesicle (v-) SNAREs and target membrane (t-) SNAREs interact specifically to control and mediate intracellular membrane fusion events. Here, cells expressing the interacting domains of v- and t-SNAREs on the cell surface were found to fuse spontaneously, demonstrating that SNAREs are sufficient to fuse biological membranes.
Video communications with optimal intra/intermode switching over wireless Internet

A robust scheme is presented for the efficient transmission of packet video over a heterogeneous channel. The channel consists of a wireless link with bit errors and a wired (e.g., Internet) channel with packet erasures. The scheme uses a source encoder that switches optimally between intracoding and intercoding with fixed-length packets. Different resynchronization schemes are considered and compared. A cyclic redundancy check (CRC) outer coder concatenated with an inner rate-compatible punctured convolutional (RCPC) coder are used as forward error correction (FEC). The scheme is evaluated over the simulated wireless Internet channel, and is shown to have promising performance.
The gut microbiota regulates K/BxN autoimmune arthritis independent of Th17 and IL-17 (BA6P.121)

The bacterial community that colonizes mucosal surfaces helps shape the development and function of the immune system. The effect of the microbiota on autoimmunity has important implications, although the mechanisms are not well understood. The K/BxN mouse model of rheumatoid arthritis is dependent on the microbiota, and particularly on segmented filamentous bacteria (SFB), for the autoimmune phenotype. Because SFB potently induce Th17 cell differentiation, previous studies have suggested Th17 cells as the link between microbiota and arthritis. In this study we sought to test directly the functional significance of Th17 and IL-17 in arthritis development by genetic approaches. We utilized mice deficient for either transcription factor RORγt (which controls the Th17 program), or the cytokine IL-17A (the major cytokine of the IL-17 family) in both cell transfer and spontaneous disease models. Unexpectedly, mice without Th17 or IL-17 were not protected from disease. Germinal center B and follicular helper T cell (Tfh) populations were normal, as were levels of serum IgG against self antigen. We found no evidence for compensation in production of the related cytokine IL-17F in IL-17A deficient mice. However, antibiotic treatment prevented disease in both IL-17 deficient and sufficient K/BxN mice, and resulted in defective Tfh and germinal center B cell differentiation. We conclude that the gut microbiota promotes autoimmune development by mechanisms independent of Th17 or IL-17.
Holography with short pulses and other broad spectrum light

ABSTRACT Holographywith very short pulses, e.g., in the femtosecond regime, has some signifcant capabilities. Also, it hassome special problems. These capabilities and problems are deSCribed, and some solutions are offered for theproblems. 1. INTRODUCTION With the develcpment of short pulse lasers, in the femtosecond regime, has come the possibility of imaging, dataacquisition and holography with extemely short pulse light. There arises the question, what kinds of imaging anddata acquisition can be done with such short pulse light beyond that which is conventionally done with cw light?Since a short pulse of light has a bandwidth greater that cw monochromatic light, or put otherwise, since a shortpulse is the superposition of many cw light beams, one might expect that the short pulse has a greater capability forgathering information about an object distribution than cw light. In some ways, this perported greater capabilitymanifests itself dramatically. The use of short pulse light for imaging through inhomogeneous media is one suchexample.' The shorter the pulse, the greater is the capability for such imagingIn another mode of imaging, we fmd that light beam comprising many wavelengths, whether the resulting lightwave is a short pulse or merely a broadband light beam, gives a capability for frequency diversity. Such diversity canbe utilized in various ways, for example, to smooth the speckle noise resulting from the interaction of coherent lightwith transmissive or reflecting objects. This method is often carried out by doing the imaging one wavelength at atime and averaging the images.The greatest imaging use for short pulse light is for giving depth resolution for reflective objects. The cw processyields an image that gives, in addition to sharp resolution in both lateral dimensions, a depth of field that allows for3-D imaging, but in a rather restrictive sense, in that object distributions outside the plane of focus (the out of planeobjects) produce coherent background light, with no reduction of total out of plane light. Despite this limitation,monochromatic holographic images are quite dramatic with their display of 3-D imagery. Then there is the confocalimaging process, which of course does reject the out of plane object light, so a confocal imaging system, scanningover a range of depths, can do optical sectioning and thereby produce a 3-D image without background light from outof focus objects. But best of all, pulse illumination allows for gating, which completely removes the out of planelight. This capability for complete separation of depths comes at a price when the recording is carried out usingpulsed-light holography, as we now show.
Structure and Function of the Polypeptides in Simian Virus 40 II. Transcription of Subviral Deoxynucleoprotein Complexes In Vitro

A deoxynucleoprotein complex (DNP-1) isolated from simian virus 40 (SV40) after disruption of the virus in an alkaline buffer contains the viral deoxyribonucleic acid (DNA) and four minor structural polypeptides. Dissociation of DNP-I by equilibrium centrifugation in CsCl yields a complex (DNP-II) that contains a small amount of polypeptide tightly bound to the viral DNA. Studies of the template activity of these deoxynucleoprotein complexes in vitro with Escherichia coli transcriptase show that the rate of transcription of DNP-I and DNP-II is 30 and 80%, respectively, compared with that of deproteinized SV40 DNA component I. In dimethyl sulfoxide gradients, the complementary ribonucleic acid (cRNA) synthesized from DNP-I is one-third to one-half the size of the cRNA species from DNA-I and DNP-II. Competition hybridization experiments show that with the E. coli transcriptase only a portion (about one-half) of the SV40 genome is transcribed with DNP-I as template, whereas most or all of the genome is transcribed with DNP-II as template. The template activity of the deoxynucleoprotein complexes with a highly active form II ribonucleic acid polymerase prepared from SV40-infected permissive cells follows similar transcription kinetics. The results indicate that structural nucleoproteins of SV40 bind nonrandomly to the viral DNA and effect the transcription of some subset of its sequences in vitro.
Frequency-dependent shear viscosity of a liquid two-dimensional dusty plasma.

The viscoelasticity of a two-dimensional (2D) liquid stronglycoupled dusty plasma is studied experimentally, without macroscopic shear. Positions and velocities of the dust particles, measured by video microscopy, are used as the inputs to the generalized Green-Kubo relation to obtain the complex viscosity $\ensuremath{\eta}(\ensuremath{\omega})$. The real part of $\ensuremath{\eta}(\ensuremath{\omega})$ (which corresponds to dissipation) diminishes gradually with frequency, while the imaginary part (which corresponds to elasticity) is peaked at a frequency below the 2D dusty plasma frequency. The viscoelastic approximation is found to accurately describe the 2D experimental results for $\ensuremath{\eta}(\ensuremath{\omega})$, yielding the Maxwell relaxation time ${\ensuremath{\tau}}_{M}=0.10\phantom{\rule{0.16em}{0ex}}\phantom{\rule{0.16em}{0ex}}\mathrm{s}$. Results for $\ensuremath{\eta}(\ensuremath{\omega})$ are compared to 2D molecular dynamics Yukawa simulations and to a previous experiment that was performed using an oscillating macroscopic shear.
Regulation of Synthesis of Methionyl-, Prolyl-, and Threonyl-Transfer Ribonucleic Acid Synthetases of Escherichia coli

Proline- and threonine-restricted growth caused a three- to fourfold derepression of the differential rate of synthesis of the prolyl- and threonyl-transfer ribonucleic acid (tRNA) synthetases, respectively. Similarly, there was approximately a 24-fold derepression in the rate of synthesis of methionyl-tRNA synthetase during methionine restriction. Addition of the respective amino acids to such derepressed cultures resulted in a repression of synthesis of their cognate synthetases. These results support previous findings and further strengthen the idea that the formation of aminoacyl-tRNA synthetases is regulated by some mechanism which is mediated by the cognate amino acids.
Search for direct photon production in 200 A GeV S + Au reactions: A status report

Direct thermal photons in the PT range of 0 - 5 GeV/c are expected to provide a sensitive probe of the hot dense matter formed in the early stage of relativistic heavy ion collisions. The production of single photons in 200 A GeV S+Au reactions has been investigated using the 3800 element Pbglass calorimeter of CERN experiment WA80. Neutral {pi}{sup o} and {eta} cross sections have been measured via their two-photon decay branch yields. In a first analysis of the WA80 results, a slight excess photon yield above that which may be accounted for by hadronic decays was observed for central collisions. A report on the status of the reanalysis of this data is presented.
On the difference between the misorientation dependences of the energies of tilt and twist boundaries

It is shown in this paper that the strain energy associated with tilt and twist boundaries, respectively, evaluated as the elastic energy of corresponding dislocation networks, depends on the misorientation, ..delta..theta, differently in each case. In particular, if all the terms of the order ..delta..theta/sup 2/ and higher have been neglected, this dependence has the generally accepted form (see e.g. (12)) ..gamma.. = ..gamma../sub o/ + B..delta..theta(A - 1n..delta..theta) in the former case, while in the latter case ..gamma.. = ..gamma../sub o/ + B..delta..theta(A + C..delta..theta - 1n..delta..theta) (A, B and C are constants). The reason lies simply in the different nature of these boundaries: the tilt boundary contains only one set of dislocations while the twist boundary contains two sets of dislocations forming a square grid. The interaction of a dislocation with the grain boundary, which is evaluated when deriving the strain energy, consists in the case of a twist boundary of interactions with both dislocations parallel and perpendicular to it, while only interactions with parallel dislocations are involved in the case of a tilt boundary. This difference is then responsible for the above differences in the functional forms of the misorientation dependence of the boundary energy.
Cardiovascular disease: Should statin therapy be expanded in patients with CKD?

The use of statins as a line of primary prevention in individuals at low risk of cardiovascular events is an area of debate. The most recent meta-analysis from the Cholesterol Treatment Trialists' (CTT) Collaboration suggests that present guidelines for prescribing statin therapy may need to be reconsidered.
Report on the dissolution meeting of the International Seismological Association, Strasbourg, April 24–25, 1922

The delegates met at the Institute de Physique du Globe, Strasbourg, April 24–25, 1922. The following allied nations were represented by delegates: Belgium, Brazil, Canada, France, Great Britain, Japan, Norway, Portugal, Spain, Switzerland, United States. Dr. Hecker (Germany), former director of the Central Bureau of the Association, and Professor de Kovesligethy (Hungary), former secretary were present. Several other states of Central Europe were represented by proxy.
Stability of steady states in nucleic acid poly[d(A‐T)] synthesis and the stirred flow reactor

The template directed synthesis of poly[d(A-T)] from the nucleoside triphosphates in the presence of DNA polymerase I is carried out continuously in a stirred flow reactor for the first time. The initial objective is to test the kinetic stability of the established steady states at various flow rates. Graphical analysis predicts instable steady states for certain high flow rates. As a consequence of instabilities multiple steady states and steady-state hysteresis may occur. Steady-state hysteresis has now been found experimentally. For a different enzyme fraction of low exonuclease activity we found the steady-state absorbance at 260 nm to be almost invariant with flow rate at high enzyme concentrations even if the flow rate was increased by a large factor. We call this phenomenon kinetic buffering. Relaxation of a large flow perturbation approaches the steady state in a sigmoidal fashion. Concentration oscillations at 260 nm occurred in one experiment using an enzyme fraction of low exonuclease activity after perturbing the steady state by monomer (dATP). Advantages of the stirred flow reactor method over serial transfer are discussed.
pSK41-Like Plasmid Is Necessary for Inc18-Like vanA Plasmid Transfer from Enterococcus faecalis to Staphylococcus aureus in vitro

Vancomycin-resistant Staphylococcus aureus (VRSA) is thought to result from the in vivo conjugative transfer of a vanA plasmid from an Enterococcus sp. to S. aureus. We studied bacterial isolates from VRSA cases that occurred in the United States to identify microbiological factors which may contribute to this plasmid transfer. First, vancomycin-susceptible, methicillin-resistant S. aureus (MRSA) isolates from five VRSA cases were tested for their ability to accept foreign DNA by conjugation in mating experiments with Enterococcus faecalis JH2-2 containing pAM378, a pheromone-response conjugative plasmid. All of the MRSA isolates accepted the plasmid DNA with similar transfer efficiencies (∼10(-7)/donor CFU) except for one isolate, MRSA8, for which conjugation was not successful. The MRSA isolates were also tested as recipients in mating experiments between an E. faecalis isolate with an Inc18-like vanA plasmid that was isolated from a VRSA case patient. Conjugative transfer was successful for 3/5 MRSA isolates. Successful MRSA recipients carried a pSK41-like plasmid, a staphylococcal conjugative plasmid, whereas the two unsuccessful MRSA recipients did not carry pSK41. The transfer of a pSK41-like plasmid from a successful MRSA recipient to the two unsuccessful recipients resulted in conjugal transfer of the Inc18-like vanA plasmid from E. faecalis at a frequency of 10(-7)/recipient CFU. In addition, conjugal transfer could be achieved for pSK41-negative MRSA in the presence of a cell-free culture filtrate from S. aureus carrying a pSK41-like plasmid at a frequency of 10(-8)/recipient CFU. These results indicated that a pSK41-like plasmid can facilitate the transfer of an Inc18-like vanA plasmid from E. faecalis to S. aureus, possibly via an extracellular factor produced by pSK41-carrying isolates.
Optical second-harmonic generation with surface plasmons in noncentrosymmetric crystals

We report an extensive investigation of optical second-harmonic generation (SHG) with the simultaneous excitation of the surface-plasmon (SP) mode at the interface between a metal and a nonlinear piezoelectric crystal. The birefringence of appropriately oriented potassium dihydrogen phosphate (KDP) crystals is utilized to demonstrate both quasi-phase-matched reflected SHG and transmitted SHG with fundamental SP excitation. The effect on the SHG resonances of the softness of the KDP crystal is discussed. Resonant SHG with fundamental SP excitation is observed for Al- and Ag-metal films on variously oriented quartz crystals. The source of the SHG for the $X$-cut orientation is the nonlinear crystal while for the $Z$-cut orientation it is the metal film. This latter result indicates that the recent observations of DeMartini et al. [Phys. Rev. B 23, 3797 (1980)] must be reinterpreted. In all our experiments, even including those in which a crystal with a large nonlinear susceptibility such as ${\mathrm{LiIO}}_{3}$ is utilized, the predicted SHG resonance due to the nonlinearly excited harmonic SP mode is always masked by the nonresonant SHG contribution from the metal itself.
An application of a fixed-point theorem to approximation theory

Abstract In this note, an extension of a theorem of Brosowski is given where linearity of the function and the convexity of the set are relaxed.
Etiologic heterogeneity of intracranial hemorrhages in preterm newborns

Hemorrhages in brain parenchyma and ventricles in preterm infants tend to be grouped as one entity. To help determine whether these hemorrhages should be viewed as one or more entities, we compared the risk profiles of 3 groups of hemorrhages defined by location and time of occurrence: early germinal matrix hemorrhage (GMH), late GMH, and late peri/intraventricular hemorrhage excluding GMH. These 3 groups were determined to have sufficient differences in various risk factors to warrant separate epidemiologic study.
On the performance evaluation of query-based wireless sensor networks

We present a queueing-theoretic framework to evaluate the performance of large-scale, query-based wireless sensor networks whose nodes detect and advertise significant events that are useful for only a limited time; queries generated by sensor nodes are also time-limited. The main performance parameter is the steady state proportion of generated queries that fail to be answered on time. Using an infinite transmission range model, we first provide an approximation for this parameter that is insensitive to the size of the network. Subsequently, we approximate the proportion of failed queries when the transmission range is limited and show that this proportion converges to its infinite range counterpart as the sensor transmission range tends to infinity. The analytical approximations are shown to be remarkably accurate when compared with benchmark values obtained using a commercial network simulator.
Nova: A Modern Platform for System Dynamics, Spatial, and Agent-based Modeling☆

Abstract In this paper we describe Nova, a new Java-based modeling platform that naturally supports the creation of models in the system dynamics, spatial and agent-based modeling paradigms. Nova uses a visual language to express model design, and provides automatic conversion for such models to script form for execution. Nova's architecture promotes hierarchical design, code reuse, and extensibility through the use of plug-ins. The Nova Website, www.novamodeler.com , is being built to foster a vibrant user community by providing ample support for model and plug-in construction, and user services such as online repositories for user-contributed content.
Localization of 5S RNA and rRNA genes in the Norway rat

The genes coding for the two classes of ribosomal RNA molecules, 5S RNA and 18+28S RNA, have been localized in the Norway rat (Rattus norvegicus). The 18+28S RNA cistrons are found on three chromosomes, at secondary constrictions on the short arms of chromosomes 3 and 12 and at the telomere of the short arm of chromosome 11. These sites were confirmed using the silver staining technique for nucleolar organizer regions. Two sites were found for the 5S RNA genes; one is closely linked to the 18+28S gene site on chromosome 12. The second site is at or near the telomere of the long arm of chromosome 19.
Managing Chemistry Underground: Is Co-Sequestration an Option in Selected Formations?

Abstract Geochemical simulations indicate that co-injection of CO2 and SO2 results in mineral sequestration of SO2. The amounts sequestered are greater and more persistent in dolomite and basalt than in glauconitic sandstone. In a predominantly dolomite formation, dissolution of calcite, and to a lesser extent, dolomite, will provide Ca in solution to promote the precipitation of anhydrite, thus removing the SO2 from solution. In basalt, dissolution of basaltic glass under acidic conditions provides Ca and Fe in solution, which promotes the sequestration of SO2 as anhydrite and, eventually, pyrite. As magnetite in the formation is consumed, pyrite redissolves. In the basalt, 86% to 47% of the SO2 remains sequestered after 5000 years. In glauconitic sandstone, SO2 precipitates as alunite, but it eventually redissolves. After 5000 years, 87% to 0% of the SO2 remains sequestered in the glauconitic sandstone. In all cases, co-injection of 1% SO2 with CO2 did not appreciably reduce the amount of CO2 sequestered, and did not induce a measureable change in porosity versus injection of CO2 alone.
Development of steady flow of liquid film over a domed cylinder

Abstract Development of steady flow of a uniform liquid film over a domed cylinder in both laminar and turbulent regimes was formulated and solved. Depending on the inlet condition, the flow may start with the accelerating or decelerating mode and arrive at the terminal velocity asymptotically.
Is liver function testing necessary prior to methotrexate treatment for ectopic pregnancy

Study objectives: Methotrexate is used extensively for the nonsurgical management of ectopic pregnancy. Hepatic function testing, specifically aminotransferase testing, was part of the initial methotrexate safety profile and continues to be routinely required before treatment with methotrexate. We seek to determine the incidence of abnormal aminotransferase values among emergency department (ED) patients with ectopic pregnancy. We examine risk factors for liver disease (eg, history of hepatitis, alcohol abuse) among patients with abnormal aminotransferase values and the time spent waiting for aminotransferase testing before methotrexate treatment. Methods: ED medical records were examined over a 4-year period for all patients with an International Classification of Diseases, Ninth Revision diagnosis of ectopic pregnancy. Patients with ectopic pregnancy were included if aminotransferase testing was performed during the ED visit. The medical record was reviewed for risk factors for liver disease if aminotransferase values were elevated. If a patient was treated with methotrexate, the time between orders for aminotransferase and methotrexate was recorded. Results: Over a 4-year period, 205 patients were diagnosed with ectopic pregnancy. Of these patients, the study group consisted of 121 patients who also had serum aminotransferase testing. In the study group, 42 patients were treated with methotrexate, and 79 were treated surgically. Two of the 121 (1.2%) patients had abnormal aminotransferase values. One patient had a normal aspartate aminotransferase (AST) level and an alanine aminotransferase (ALT) level of 43 U/L (reference range 15 to 40 U/L). This patient had a history of hepatitis C. The second patient had a normal ALT level and an AST level of 81 U/L (reference range 15 to 65 U/L). This patient had a history of alcohol abuse. Of the 42 patients treated with methotrexate, the mean time between orders for aminotransferase testing and methotrexate administration was 102 minutes (95% confidence interval 94 to 109 minutes). Conclusion: Among patients with ectopic pregnancy being considered for methotrexate treatment, the incidence of aminotransferase abnormalities is low. Aminotransferase testing significantly prolonged ED treatment time among patients receiving methotrexate. Further prospective study may identify a majority of patients who may be treated with methotrexate without previous aminotransferase testing.
Sphere mass center determination by velocity modulation

Abstract This paper presents a new technique, called velocity modulation, for measuring the mass center location of a sphere, improving upon the accuracy of previous methods by at least a factor of 4. The sphere is rolled down a set of parallel rails. The offset of the sphere’s mass center with respect to its geometric center modulates the sphere’s velocity at the rolling frequency, which is detected by a series of differential optical shadow sensors. The measured times that the sphere crosses the sensors is compared with a simplified mechanics model in order to recover the sphere’s mass center location. The precision of the technique is demonstrated by the repeatability of independent measurements in one plane of a 50.8 mm (2 in.) stainless steel gage sphere. The best standard deviation achieved is 145 nm (95% confidence interval = 227 nm).
Giving voice to the gift: The use of projective techniques to recover lost meanings

The field of consumer–object relations has recently emerged as a significant area of inquiry. Renewed attention has been devoted to understanding the meanings of gift giving as a result of this emergence. In this study, we employ projective techniques to uncover meanings that are less accessible by more direct measures. We analyze these meanings, and demonstrate the utility of projective techniques as a complement to other methods of investigation.
Book Reviews: Two Recent Books on Traditional Chinese Medicine and AIDS

The development of a purified and crystallized protein called trichosanthin, used in China for inducing abortion, and imported into the USA for curing AIDS infection under the name "compound Q," is carefully reviewed. Another book on the use of the principles and practices of traditional Chinese medicine for the health care of AIDS patients is critically reviewed with a few suggestions for future improvement in respect to Chinese herbal products. The reviewer has worked on the medicinal plants of China since 1935, with extensive field experience of botanization throughout China, from the coastal provinces to the Qinghai-Tibetan Plateau, and from Heilungjian to Yunnan; and with the herbaria and library facilities of Harvard University since 1945.
A double-helix neutron detector using micron-size 10 B powder

Abstract A double-helix electrode configuration is combined with a 10 B powder coating technique to build large-area (9 in.×36 in., or about 23 cm by 91 cm) neutron detectors. The neutron detection efficiency for each of the four prototypes is comparable to 3.7×10 3 cm 3 of 3 He inside a cylindrical tube 91 cm long. One unit has been operational continuously for 18 months and the change of efficiency is less than 1%. An analytic model for pulse height spectra is described and the predicted mean film thicknesses agree with the experiment to within 30%. Further detector optimization is possible through film texture, powder size, moderator box and gas. The estimated production cost per unit is less than 3k US$ and the technology is thus suitable for deployment in large numbers.