cssi/SciSciGPT-SciSciNet huggingface dataset:
Technical Consideration for TLIF Cage Retrieval and Deformity Correction With Anterior Interbody Fusion in Lumbar Revision Surgeries

Abstract Introduction Symptomatic pseudoarthrosis after transforaminal lumbar interbody fusion (TLIF) could result in sagittal malalignment. Revision posterior surgery with TLIF cage removal poses a challenge intraoperatively. The authors have proposed salvage anterior approach for cage removal and have discussed unique experience with the correction in their deformity patients. Methods All patients with symptoms of clinical deformity or symptomatic pseudoarthrosis operated from January of 2012 to February of 2018 were included in the study. TLIF cage removal followed by anterior lumbar interbody fusion (ALIF) surgery was performed in all patients. Radiographic sagittal parameters including thoracic kyphosis (TK; T4–T12), sagittal vertical axis (SVA), T1 pelvic angle (TPA), lumbar lordosis (LL), the mismatch between pelvic incidence (PI) and LL (PI-LL), sacral slope (SS), pelvic tilt (PT), and PI were analyzed. Results 6 patients (mean age of 57 years, 83% female) underwent TLIF retrieval through anterior approach and ALIF with hyperlordotic cages (HLCs), followed by posterior spinal fusion surgery. Described technique entails use of tailored instruments with sequential gentle distraction of end plates with TLIF spreader could facilitate in the cage removal. Mean number of interbody levels fused pre as well as post were 1.5. The radiographic sagittal parameters from preoperative versus postoperative standing were as follows: T4–T12 TK, 16° vs. 37.6°; LL, −25° vs. −47.6°; PT, 36° vs. 26°; PI-LL, 35° vs. 12.4°; SVA, 12° vs. 5.6°; and TPA, 44° vs. 25°, with p Conclusions Anterior approach is a suitable technique for TLIF cage removal while preserving the end plates for subsequent optimal interbody fusion at the index level in symptomatic pseudoarthrosis patients or those with clinical deformity. ALIF with HLCs with or without Ponte osteotomy can restore segmental and overall sagittal alignment.
Spatial Release from Masking Using Clinical Corpora: Sentence Recognition in a Colocated or Spatially Separated Speech Masker

Background Speech recognition in complex multisource environments is challenging, particularly for listeners with hearing loss. One source of difficulty is the reduced ability of listeners with hearing loss to benefit from spatial separation of the target and masker, an effect called spatial release from masking (SRM). Despite the prevalence of complex multisource environments in everyday life, SRM is not routinely evaluated in the audiology clinic. Purpose The purpose of this study was to demonstrate the feasibility of assessing SRM in adults using widely available tests of speech-in-speech recognition that can be conducted using standard clinical equipment. Research Design Participants were 22 young adults with normal hearing. The task was masked sentence recognition, using each of five clinically available corpora with speech maskers. The target always sounded like it originated from directly in front of the listener, and the masker either sounded like it originated from the front (colocated with the target) or from the side (separated from the target). In the real spatial manipulation conditions, source location was manipulated by routing the target and masker to either a single speaker or to two speakers: one directly in front of the participant, and one mounted in an adjacent corner, 90° to the right. In the perceived spatial separation conditions, the target and masker were presented from both speakers with delays that made them sound as if they were either colocated or separated. Results With real spatial manipulations, the mean SRM ranged from 7.1 to 11.4 dB, depending on the speech corpus. With perceived spatial manipulations, the mean SRM ranged from 1.8 to 3.1 dB. Whereas real separation improves the signal-to-noise ratio in the ear contralateral to the masker, SRM in the perceived spatial separation conditions is based solely on interaural timing cues. Conclusions The finding of robust SRM with widely available speech corpora supports the feasibility of measuring this important aspect of hearing in the audiology clinic. The finding of a small but significant SRM in the perceived spatial separation conditions suggests that modified materials could be used to evaluate the use of interaural timing cues specifically.
Brief intervention targeting letter sounds, letter naming, and segmenting frequency skills show promise for improving spelling accuracy1

Q What is the effect of building the frequency of letter sound identification, letter naming, and sound segmenting skills on spelling accuracy among at-risks early-elementary students? The authors ...
Baseline Gut Microbiota Composition Is Associated with Major Infections Early after Hematopoietic Cell Transplantation.

ABSTRACT Infection is a major cause of morbidity and mortality after hematopoietic cell transplantation (HCT). Gut microbiota (GM) composition and metabolites provide colonization resistance against dominance of potential pathogens, and GM dysbiosis following HCT can be deleterious to immune reconstitution. Little is known about the composition, diversity, and evolution of GM communities in HCT patients and their association with subsequent febrile neutropenia (FN) and infection. Identification of markers before HCT that predict subsequent infection could be useful in developing individualized antimicrobial strategies. Fecal samples were collected prospectively from 33 HCT recipients at serial time points: baseline, post-conditioning regimen, neutropenia onset, FN onset (if present), and hematologic recovery. GM was assessed by 16S rRNA sequencing. FN and major infections (ie, bloodstream infection, typhlitis, invasive fungal infection, pneumonia, and Clostridium difficile enterocolitis) were identified. Significant shifts in GM composition and diversity were observed during HCT, with the largest alterations occurring after initiation of antibiotics. Loss of diversity persisted without a return to baseline at hematologic recovery. GM in patients with FN was enriched in Mogibacterium, Bacteroides fragilis, and Parabacteroides distasonis, whereas increased abundance of Prevotella, Ruminococcus, Dorea, Blautia, and Collinsella was observed in patients without fever. A baseline protective GM profile (BPGMP) was predictive of protection from major infection. The BPGMP was associated with subsequent major infections with 77% accuracy and an area under the curve of 79%, with sensitivity, specificity, and positive and negative predictive values of 0.71, 0.91, 0.77, and 0.87, respectively. Our data show that large shifts in GM composition occur early after HCT, and differences in baseline GM composition are associated with the development of subsequent major infections.
Comparative morphology of cotylephores in Platystacus and Solenostomus: modifications of the integument for egg attachment in skin-brooding fishes

External skin brooding evolved independently in several groups of fishes. Cotylephores, sites for the attachment of developing embryos, occur within the fused pelvic fins of the ghost pipefishes, Solenostomus, on the ventral surface of the South American catfish, Platystacus, and on other aspredinid cattfishes of the tribe Aspredini. Cotylephores are transient outgrowths of tissue that occur only on brooding fish. They consist of a pedicle that extends from the abdomen or fin and terminates in an apical calyx. The calyx supports and adheres to the egg envelope that encloses the developing embryo. The pedicle of the catfish cotylephore is a single, large structure (1615 ± 23.25 µm), while those of ghost pipefishes are small and branched (687 ± 3.89 µm; number of branches: 26 ± 0.63). In both instances, a simple cuboidal epithelium, whose cells bear microplicae, encloses an extensive connective tissue core that contains large blood vessels that ramify into a capillary plexus in the calyx. Cotylephores of Platystacus are more heavily vascularized than those of Solenostomus and contain 34.77% more blood vessel surface area at the calyx, to which the egg envelope adheres. In addition to their role in attachment, cotylephores may function in embryonic maintenance through the exchange of gas across the egg envelope, mediated by female circulatory vessels within the cotylephore calyx. Comparisons of morphology and development suggest that cotylephores are the result of convergent evolution of a reproductive adaptation.
Epiglottic hematoma after carotid endarterectomy with cervical block.

Abstract There are few trials assessing the risks and benefits of performing a cervical plexus block (CPB) in urgent carotid endarterectomies (CEA). We describe a case of a patient who underwent urgent CEA under CPB and suffered a complication of postoperative epiglottic hematoma. There were clinical findings that helped to distinguish the hematoma from other, more common postoperative complications. The mainstay of treatment was steroids and observation. Epiglottic hematomas after cervical blocks for CEAs are rare but potentially lethal complications. More research is needed investigating complications related to CPBs performed for CEAs.
Efficient numerical processing of off-axis digital holographic images

Numerical reconstruction of digital holographic images can be inefficient in cases of a limited region of interest in the image plane. Here we show a discrete Fourier transform can be computationally faster than traditional methods.
Examining Longitudinal Patterns of Special Education Service Receipt

It is important to understand how longitudinal patterns of special education placement differ from cross-sectional incidence estimates in order to improve measurement precision and better target as...
Characteristics Influencing Academic Librarians’ Political Skills: Keys to Organizational Effectiveness and Career Success

Academic librarians seldom view their organizations through the political frame. Yet, strong political skills are necessary for organizational effectiveness and career success. Using the Political ...
Fully Distributed Optimization based CAV Platooning Control under Linear Vehicle Dynamics

This research work is supported by the NSF grants CMMI-1901994 and CMMI-1902006. We thank Benjamin Hyatt of University of Maryland Baltimore County for his contribution to the proof of the closed loop stability when p = 3.
Time-lapse seismic data reconstruction using compressive sensing

ABSTRACTThe time-lapse seismic method plays a critical role in reservoir monitoring and characterization. However, time-lapse data acquisitions are costly. Sparse acquisitions combined with postacq...
Results of Single-Event Latchup Measurements Conducted by the Jet Propulsion Laboratory

This paper reports recent single-event latchup (SEL) results for a variety of microelectronic devices that include OpAmp, Voltage Reference, Motor Controller, Switch Mode Controller, Resolver-to-Digital Converter and Analog-to-Digital Converter. The data was collected to evaluate these devices for possible use in NASA spacecraft.
An unexpected role for Dicer as a reader of the unacetylated DNA binding domain of p53 in transcriptional regulation

Here, we identified Dicer as a major cellular factor that recognizes the DNA binding domain (DBD) of p53 in a manner dependent on its acetylation status. Upon binding the unacetylated DBD, Dicer is recruited to the promoters of p53 target genes, where it represses p53-mediated transcriptional activation. Conversely, knockdown or knockout of endogenous Dicer leads to up-regulation of p53-mediated transcriptional activation without increasing its protein levels. Moreover, Dicer-mediated repression is independent of its intrinsic endoribonuclease activity; instead, Dicer directly represses transcription by recruiting the SUV39H1 histone methyltransferase. However, upon DNA damage, Dicer-mediated repression is abrogated by stress-induced acetylation at the DBD of p53. Notably, the inability of acetylation-defective p53-3KR in transcription is partially but significantly restored upon loss of Dicer expression. Our study reveals that Dicer acts as an unexpected acetylation “reader” for p53 and thus has important implications regarding the mechanism of acetylation-mediated regulation of p53 transcriptional program.
Introduction to the Special Issue on Nature, Nurture, and the Development of Exceptional Competence

The nature and nurture of exceptional competence is a key foundational issue for gifted education. This special issue is intended to present the most current thinking about the issue by a group of leading psychological researchers from diverse traditions. The introduction of the following 5 articles is organized around 3 themes: (a) nature versus nurture (additive influence of each), (b) nature and nurture (reciprocation and interaction of the 2), and (c) nature in nurture (nature mediated by, or revealed through, nurture). It is argued that the progression from the nature-nurture debate to interactionist perspectives, to a further consideration of nature and nurture as working as 1 system, represents a more refined and deeper understanding of the role of nature and nurture in the development of exceptional competence.
Correcting for Self-selection Bias in Business Ethics Research

Self-selection bias occurs when there is non-random sampling of membership within a group or category, such as employment status, that is hypothesized to affect a variable of interest, such as ethical attitudes or behaviors. Self-selection bias is germane to a variety of important business ethics questions, such as how the business environment affect personal ethics or whether business students are more or less ethical than non-business students. This paper describes an empirical technique to control for self-selection bias. The technique is applied to the empirical question of whether the employment status of workers is correlated with ethical proclivities. Correcting for self-selection bias shows that an observed negative correlation between employment and ethics is the result of self-selection rather than factors associated with employment, other things being equal.
ACTION OF HAEMOPHILUS CULTURES ON δ-AMINOLEVULINIC ACID

Biberstein, Ernst L. (University of California, Davis), Patricia D. Mini, and Marjorie G. Gills. Action of Haemophilus cultures on delta-aminolevulinic acid. J. Bacteriol. 86:814-819. 1963.-Utilization of delta-aminolevulinic acid (ALA) by strains of Haemophilus recovered from various sources was investigated. With the 37 cultures studied, there was perfect correlation between absence of hemin requirement and ability to convert ALA to porphyrin. A total of 29 strains, including representatives of H. parainfluenzae, H. parahaemolyticus, H. "parasuis," and H. gallinarum, fell into this group. The remaining eight isolates, which were incapable of porphyrin synthesis from ALA, were strains of H. influenzae, H. suis, and a Haemophilus culture of uncertain classification obtained from a splenic abscess in a deer. In the active preparations, the products of synthesis included a mixture of porphyrins, porphobilinogen (PBG), and a pigment which absorbed light strongly at 470 to 480 mmu. Paper chromatographic studies of fractions of supernatants and cells revealed the presence of porphyrins having R(F) values similar to those of uro- and protoporphyrins, as well as some intermediate rates of migration probably representing coproporphyrins. Porphyrins were found both intra- and extracellularly, and PBG and the pigment absorbing at 470 to 480 mmu were confined to the supernatant.
Photochemical Processes in the Mesosphere and Lower Thermosphere

In the mesosphere and lower thermosphere (between 50–120 km), photochemical processes produce important minor constituents that can effect the thermal, radiative and electrical properties of the atmosphere. Since the subject of atmospheric photochemistry is very extensive, only an introduction to selected topics is given. We first introduce the basic concepts; the hydrostatic law, transport processes, the absorption of solar radiation, and chemical kinetic processes. Next the density profiles of the minor species, O, O3, H, OH, and HO2 in the mesosphere are illustrated by solving the one-dimensional continuity equation. The profiles of the longer-lived species NO, H2O, and 0 in the lower thermosphere are also discussed. The final portion outlines the ion chemistry of the lower E-region and the D-region. The photochemical control of the ion composition is emphasized.
Hypoxia by degrees: Establishing definitions for a changing ocean

Abstract The marked increase in occurrences of low oxygen events on continental shelves coupled with observed expansion of low oxygen regions of the ocean has drawn significant scientific and public attention. With this has come the need for the establishment of better definitions for widely used terms such as “hypoxia” and “dead zones”. Ocean chemists and physicists use concentration units such as μ molO 2 / kg for reporting since these units are independent of temperature, salinity and pressure and are required for mass balances and for numerical models of ocean transport. Much of the reporting of dead zone occurrences is in volumetric concentration units of mlO2/l or mgO2/l for historical reasons. And direct measurements of the physiological state of marine animals require reporting of the partial pressure of oxygen (pO2) in matm or kPa since this provides the thermodynamic driving force for molecular transfer through tissue. This necessarily incorporates temperature and salinity terms and thus accommodates changes driven by climate warming and the influence of the very large temperature range around the world where oxygen limiting values are reported. Here we examine the various definitions used and boundaries set and place them within a common framework. We examine the large scale ocean pO2 fields required for pairing with pCO2 data for examination of the combined impacts of ocean acidification and global warming. The term “dead zones”, which recently has received considerable attention in both the scientific literature and the press, usually describes shallow, coastal regions of low oxygen caused either by coastal eutrophication and organic matter decomposition or by upwelling of low oxygen waters. While we make clear that bathyal low oxygen waters should not be confused with shallow-water “dead zones”, as deep water species are well adapted, we show that those waters represent a global vast reservoir of low oxygen water which can readily be entrained in upwelling waters and contribute to coastal hypoxia around the world and may be characterized identically. We examine the potential for expansion of those water masses onto continental shelves worldwide, thereby crossing limits set for many not adapted species.
Computational Study of Unsteady Flows around Dragonfly and Smooth Airfoils at Low Reynolds Numbers

A computational study was conducted to investigate the unsteady quasi-two-dimensional flow around a streamlined NASA low-speed GA(W)-1 airfoil and a corrugated dragonfly airfoil at the Reynolds numbers of 68,000 and 55,000. Both 2D and 3D simulations were carried out by solving the unsteady Navier-Stokes equations to predict the behavior of the unsteady flow structures around the airfoils at different angles of attack (AOAs). Extensive comparisons were made between the numerical results and wind-tunnel experimental results for the same configurations. It was found that the 2D and 3D simulations differ significantly at relatively high AOAs, and that the 3D computational results agree much better with the experimental data. It is believed that unsteady vortex-dominated flow at high angle of attack is strongly three-dimensional. As a result, the 2D simulations are not adequate in resolving the fundamental flow physics, and 3D simulations are necessary to correctly predict the flow behavior at such conditions.
The relationship between resting heart rate variability and heart rate recovery

Objective There is limited research available regarding a possible relationship between resting heart rate variability (HRV) and post-exercise heart rate recovery (HRR). The aim of this study was to examine the relationship between resting HRV and HRR after maximal exercise. Methods Sixty-six college age men participated in this study. HRV was measured in a supine position before and for 30 min after a maximal exercise test on a treadmill. HRV was assessed in the time (i.e., SDNN) and frequency (i.e., normalized HF power [HFnu] and normalized LF:HF ratio [LFnu:HFnu]) domains. Heart rate was recorded at maximal exercise (MHR), and at 1- (HR1) and 2(HR2) min of the cool-down recovery period. HRR was determined from the difference between MHR and HR1 (HRR1) and the difference between MHR and HR2 (HRR2).
Education for design

Abstract The notion of design adopted in this paper embraces the design of all human systems. The design tasks envisaged focus on processes rather than structures. They are viewed in the light of multi-level and multi-goal systems representation based on total human experience and aiming at coordination rather than control from the top. Education for design should focus primarily on the design of human relations, instrumentalities and institutions, along with their respective role patterns. The nature of learning at these three steps is seen as the cybernetic evolution of measure, norms and values respectively.
Use of ileocecal continent urinary reservoir in patients with previous pelvic irradiation.

Abstract Objective. To assess the results of the use of ileocecal continent urinary reservoirs in patients with previous pelvic irradiation. Methods. A retrospective analysis for morbidity and clinical outcome was undertaken for 37 female patients with prior therapeutic pelvic irradiation who underwent continent urinary diversion with a detubularized right colonic segment as the urinary reservoir, a plicated ileocecal valve as the continence mechanism, and a tapered distal ileum for efferent catheterization. Results. Thirty-one patients had persistent or recurrent pelvic malignancies, 17 of whom had total pelvic exenteration and 14 had anterior exenteration. The remaining 6 patients had radiation-induced vesicovaginal fistulas without evidence of recurrence and underwent urinary diversion alone. Follow-up ranged from 2 to 33 months (median 11 months). Postoperative radiographic evaluation revealed no evidence of urinary extravasation. Of the 74 implanted ureters, 4 had reflux (5%), 2 developed stricture (3%), and 5 had mild to moderate hydronephrosis (7%). All patients achieved daytime continence with catheterization intervals of 3–8 hr (median 4 hr) and capacities of 200–1000 cc (median 500 cc). Nighttime continence was reported by 33 of 37 patients (89%). Reoperation was required in 3 patients (8%), 2 with stoma stenosis and 1 with difficulty in catheterization. Conclusions. The use of the ileocecal continent urinary reservoir in patients with previous pelvic irradiation achieves results comparable to those reported for nonirradiated patients, thus supporting its use in this select group of patients.
Perturbation Theory for an Infinite Medium of Fermions. II

The ground-state energy and low-energy excitations of single-particle character of an infinite medium of fermions are discussed with the aid of time- dependent Green's functions, which are convenient generalizations of the exact particle correlation functions in the ground state of N particles. The power series development for the one- and two-particle functions, under the restriction to two-body forces, is derived and described by means of Feynman diagrams. The derivation of the linked-cluster expansion for the energy then follows immediately. The equivalence to previous versions is established. The one- particle function is examined in particular detail, and it is shown that the poles of its space-time Fourier transform studied as a function of the energy variable, for fixed momentum, determined the (N + 1)-particle and (N - 1)- particle excited states which have single-particle character. For a reasonable assumption about the full spectrum of excited states, it is found that for the interacting system, single-particle excitations with a real energy occur only at the Fermi momentam. It is pointed out that the corresponding energy, termed the perturbed Fermi energy, equals the binding energy per particle in the ground state of N particles for a satarating system at equilibrium density. It ismore » shown, finally, that the entire structare of the theory may be carried over to the case of finite temperatare, requiring only a redefinition of the Green's functions. The analogy is constructed from a discussion of the internal energy. (auth)« less
Porcine models of digestive disease: the future of large animal translational research.

There is increasing interest in nonrodent translational models for the study of human disease. The pig, in particular, serves as a useful animal model for the study of pathophysiological conditions relevant to the human intestine. This review assesses currently used porcine models of gastrointestinal physiology and disease and provides a rationale for the use of these models for future translational studies. The pig has proven its utility for the study of fundamental disease conditions such as ischemia-reperfuion injury, stress-induced intestinal dysfunction, and short bowel syndrome. Pigs have also shown great promise for the study of intestinal barrier function, surgical tissue manipulation and intervention, as well as biomaterial implantation and tissue transplantation. Advantages of pig models highlighted by these studies include the physiological similarity to human intestine and mechanisms of human disease. Emerging future directions for porcine models of human disease include the fields of transgenics and stem cell biology, with exciting implications for regenerative medicine.
Exploring the determinants of emerging bioenergy market participation

Abstract Individual biomass producers will play a strong role in the emergence of robust and sustainable bioenergy markets. Research on what drives their participation, however, is substantial but fragmented. Despite a recognition of producer heterogeneity, there have also been few comparative analyses of drivers of bioenergy market participation across feedstock types, producer groups, and geographic regions. Through narrative review and network analysis, the following review of the bioenergy market participation literature generates both an increased appreciation of how bioenergy market participation is assessed in existing research and how social network analysis may be further employed as a tool for literature review. Across 41 studies selected for qualitative review and a subset of 22 selected for quantitative review, the analysis reaches two central conclusions. The first pertains to the findings of the literature itself, suggesting that a variety of non-production objectives, structural and social constraints, and market-related attributes influence bioenergy market participation decisions. A second conclusion is that the assessment of these factors varies significantly across the literature for both user group and feedstock type. Further examination of the individual variables within these segments of the literature, as well as of authorship patterns across them, suggests that this variation may rise from differences in the subject matter itself and not from differing perspectives of the researchers undertaking the work. Should disparities in the literature be reflective of actual socio-economic differences in their respective markets, policies or programs targeted to individual feedstock types or user groups may be more effective in encouraging participation than uniform national policy initiatives.
Nicotine Raises the Influx of Permeable Solutes across the Rat Blood—Brain Barrier with Little or No Capillary Recruitment:

Nicotine (1.75 mg/kg s.c.) was administered to rats to raise local CBF (lCBF) in various parts of the brain, test the capillary recruitment hypothesis, and determine the effects of this increase in lCBF on local solute uptake by brain. lCBF as well as the local influx rate constants (K1) and permeability-surface area (PS) products of [14C]antipyrine and [14C]-3-O-methyl-d-glucose (30MG) were estimated by quantitative autoradiography in 44 brain areas. For this testing, the finding of significantly increased PS products supports the capillary recruitment hypothesis. In 17 of 44 areas, nicotine treatment increased lCBF by 30–150%, K1 of antipyrine by 7–40%, K1 of 30MG by 5–27%, PS product of antipyrine by 0–20% (mean 7%), and PS product of 30MG by 0–23% (mean 8%). Nicotine had no effect on blood flow or influx in the remaining 27 areas. The increases in lCBF and K1 of antipyrine were significant, whereas those in K1 of 30MG and in PS for both antipyrine and 30MG were not statistically significant. The lack ...
In vivo increase in hypothalamic cyclic AMP following 5-hydroxytryptophan administration in rats.

The administration of 5-hydroxytryptophan (5-HTP, 100 mg/kg, i.p.) consistently increased hypothalamic cyclic AMP levels in rats treated 10 days earlier with the serotonin neurotoxin, 5,7-dihydroxytryptamine (5,7-DHT), to produce 5-HT receptor supersensitivity. However 5-HTP (100 mg/kg), failed to cause an increase in hypothalamic cyclic AMP in rats not pretreated with 5,7-DHT. The 5-HTP-induced increase in cyclic AMP was blocked by the decarboxylase inhibitor, benserazide (RO 44602, 800 mg/kg) and by the 5-HT antagonist metergoline (5 mg/kg). Other treatments that caused a significant elevation of hypothalamic cyclic AMP included: (a) l-Tryptophan plus the monoamine oxidase inhibitor, tranylcypromine, and (b) the serotonin agonist, 1-(m-trifluromethylphenyl)-1-piperazine.
Preparation and properties of (η-C5H5)2ZrCl[Si(CH3)3] and (η-C5H5)2Zr[Si(CH3)3]2; trimethylsilyl group transfer from mercury to zirconium

Abstract Two silyl-zirconium compounds (η-C 5 H 5 ) 2 ZrCl[Si(CH 3 ) 3 ] (I) and (η-C 5 H 5 ) 2 -Zr[Si(CH 3 ) 3 ] 2 (II), have been prepared by the reaction of (η-C 5 H 5 ) 2 ZrCl 2 with Hg[Si(CH 3 ) 3 ] 2 in refluxing benzene. While I is unreactive toward 1-hexyne (55–60°C) and CO (350 psi), the zirconiumsilicon bond is cleaved by electrophiles such as Cl 2 , HgCl 2 , and AlCl 3 .
R9Mg34Zn57 icosahedral quasicrystals : The tuning of a model spin glass

Abstract The growth of large single grains of face-centered icosahedral R 9 Mg 34 Zn 57 (R=Y, Gd–Er) quasicrystals (referred to as RMgZn from here on) has allowed the detailed study of the intrinsic properties of single phase samples that contain a quasiperiodic rare earth sublattice. By comparison of GdMgZn (Heisenberg moment) to TbMgZn or DyMgZn (non-Heisenberg moments) a clearly reduced freezing temperature ( T f ) for GdMgZn can be observed. In order to explore this further pseudo-ternary series such as (Y 1− x Gd x )MgZn, (Tb 1− x Gd x )MgZn, (Dy 1− x Gd x )MgZn, and (Dy 1− x Tb x )MgZn were grown. Whereas T f changes monotonically with x for the Gd/Y and Tb/Dy series, there is a rapid rise in T f for the addition of small amounts of the non-Heisenberg moments Tb or Dy into GdMgZn. For approximately 30% non-Heisenberg substitution on the Gd site T f passes through a local maximum and is reduced in a roughly linear manner for further increases in the concentration of non-Heisenberg moments. Analysis of these data lead to the conclusion that there is a threshold concentration of non-Heisenberg moments needed to force the whole system to act in a non-Heisenberg manner.
The α Subunit of the G Protein G13 Regulates Activity of One or More Gli Transcription Factors Independently of Smoothened

Smoothened (Smo) is a seven-transmembrane (7-TM) receptor that is essential to most actions of the Hedgehog family of morphogens. We found previously that Smo couples to members of the Gi family of heterotrimeric G proteins, which in some cases are integral although alone insufficient in the activation of Gli transcription factors through Hedgehog signaling. In response to a report that the G12/13 family is relevant to Hedgehog signaling as well, we re-evaluated the coupling of Smo to one member of this family, G13, and investigated the capacity of this and other G proteins to activate one or more of forms of Gli. We found no evidence that Smo couples directly to G13. We found nonetheless that Gα13 and to some extent Gαq and Gα12 are able to effect activation of Gli(s). This capacity is realized in some cells, e.g. C3H10T1/2, MC3T3, and pancreatic cancer cells, but not all cells. The mechanism employed is distinct from that achieved through canonical Hedgehog signaling, as the activation does not involve autocrine signaling or in any other way require active Smo and does not necessarily involve enhanced transcription of Gli1. The activation by Gα13 can be replicated through a Gq/G12/13-coupled receptor, CCKA, and is attenuated by inhibitors of p38 mitogen-activated protein kinase and Tec tyrosine kinases. We posit that G proteins, and perhaps G13 in particular, provide access to Gli that is independent of Smo and that they thus establish a basis for control of at least some forms of Gli-mediated transcription apart from Hedgehogs.
The comparative value of ladino clover, birdsfoot trefoil, timothy and alfalfa hays for yield and quality of milk.

Summary Two experiments are reported on the value of different hays for milk production. In the first study, 15 Holstein cows were fed six types of hay in an incomplete block design experiment involving four periods of 5 wk. each. The hays studied included early-cut timothy, late-cut timothy, second crop alfalfa cut at early and late stages of maturity, birdsfoot trefoil ( Lotus corniculatus ) and ladino clover. Measurements were made of the palatability of the hays and of their effects upon milk production, and on the carotene, vitamin A and tocopherol contents and stability of the milk. The legume hays and early-cut timothy were approximately equal in value, but the late-cut timothy proved much less palatable and resulted in lower milk production than any of the other hays. On ad lib . feeding the average intake of late-cut timothy was only 35 to 44 per cent as much as of the other hays and the actual milk production was approximately 25 per cent lower. Milk of poor keeping qualities resulted during ladino clover feeding and appeared to be correlated with a low content of tocopherol in the milk fat. A second study with similar hays using four cows in a 4×4 Latin square design gave data in good agreement with the first test.
Minimally invasive techniques in breast cancer treatment.

Breast conservation therapy has largely replaced mastectomy as the surgical treatment of choice for early-stage breast cancer. As the sentinel lymph node mapping procedure, rather than routine axillary node dissection, becomes the standard of care, the next challenge is how to treat the primary tumor without surgery. Minimally invasive ablation of the primary tumor is possible with a variety of approaches; the goal is to either excise the tumor percutaneously or cool it (with cryotherapy) or heat it (with radiofrequency ablation (RFA), focused ultrasound, or laser interstitial therapy) sufficiently to cause complete cell death. These developing technologies may provide treatment options that are psychologically and cosmetically more acceptable to the patient than traditional therapies, but they need further investigation to prove that they are oncologically sound. This new frontier of surgery without scalpels will require surgeons to develop radiologic expertise and to acquire a basic understanding of molecular biology.
Transition metal and organic radical components of carp liver tissue observed by electron paramagnetic resonance spectroscopy

Abstract Paramagnetic transition metal centers and organic radicals in liver from wild-type carp ( Cyprinus carpio ) were characterized by electron paramagnetic resonance (EPR) spectroscopy. Approximately twelve EPR signals were observed at 77 K with resonance positions between g =1.8 and g =2.5. Identification was facilitated by a study of the variation in signal intensity with microwave power (microwave power saturation) for each signal. Many were organic radical or iron signals from typical liver enzymes, including cytochrome P450, coenzyme Q 10 , NADH dehydrogenase, and succinate dehydrogenase, cytochrome c oxidase and/or catalase. Of special interest were two signals that are not normally found in mammalian liver. The first was a six-line signal from divalent manganese, which was evident in the spectra in quantities suggestive of a functional role. The second was probably a signal from nitrosylated non-heme iron and may be related to the presence of nitrogen-containing compounds produced by nitrifying bacteria in the aquatic environment. These notable differences between the EPR spectra of fish and mammalian liver suggest major metabolic differences between the two systems.
Revised Design Procedure for Thin and Ultrathin Bonded Whitetopping

Development of design procedures for bonded whitetopping overlays has been based on the assumption that failure mechanisms are a function of overlay thickness; namely, thin whitetopping results in longitudinal cracking and ultrathin whitetopping results in corner cracking. However, field data from whitetopping sections indicate that failure modes are dictated by slab size rather than overlay thickness. The revised procedure presented here for thin whitetopping and ultrathin whitetopping offers four primary enhancements to the Portland Cement Association and Colorado Department of Transportation procedures that traditionally have been used: (a) the failure mode is dictated by the joint spacing and not the overlay thickness, (b) the stress adjustments factors have been calibrated with an extensive data set, (c) the equivalent gradients to be used as the design input are defined according to the pavement structure and geographical location of the project and, (d) the effect of temperature change on hot-mix a...
Intercarrier interference cancellation for wideband OFDM in high speed aerial vehicle communication

It is well known that Orthogonal Frequency Division Multiplexing (OFDM) systems suffer from intercarrier interference (ICI) in mobile environment due to loss of orthogonality among subcarriers caused by Doppler shifts. There exist many ICI mitigation techniques in the literature to improve the performance of OFDM systems. However, most of the existing ICI mitigation techniques assume the OFDM transmission bandwidth is narrow enough that the frequency offsets on all subcarriers are identical. In a wideband OFDM transmission or a non-contiguous OFDM spanning over large bandwidth, the Doppler shifts on different subcarriers are different, especially in high speed aerial vehicle communication systems. In this paper, we analyze the wideband OFDM system in high mobility environment where the frequency offsets vary from subcarrier to subcarrier. We then propose a novel ICI cancellation scheme to eliminate the ICI effect and offer the wideband OFDM system significantly improved BER performance. Simulation results in AWGN channel and multipath fading channel confirm the effectiveness of the proposed scheme in the presence of frequency offset and time variations in the channel, offering the best BER performance available which matches the BER performance of wideband OFDM system without ICI. To our knowledge, this paper is the first to address the ICI problem of varying frequency offsets across subcarriers in wideband OFDM system.
Torsion of a flattened tube

The torsion of a hollow cylinder with elongated cross-section is studied theoretically by an efficient eigenfunction expansion and modified point-match method. The effects of the geometric parameters on torsional rigidity and maximum shear stress are determined.
ProofChecker: an accessible environment for automata theory correctness proofs

ProofChecker is a graphical program based on the notion of formal correctness proofs that allows students, both sighted and visually impaired, to draw a deterministic finite automaton (DFA) and determine whether or not it correctly recognizes a given language. Sighted students use the mouse and graphical controls to draw and manipulate the DFA. Keyboard shortcuts, together with the use of a screen reader to voice the accessible descriptions provided by the program, allow visually impaired students to do the same. Because the states of a DFA partition thelanguage over its alphabet into equivalence classes, each state has a language associated with it. Conditions that describe the language of each state are entered by the student in the form of conditional expressions with function calls and/or regular expressions. A brute-force approach is then used to check that each state's condition correctly describes all of the strings in its language and that none of the strings in a state's language meet the condition for another state. Feedback is provided that either confirms that the DFA correctly meets thegiven conditions or alerts the student to a mismatch between the conditions and the DFA. A student's DFA can be saved in an XML file and submitted for grading. An automated checking tool, known as ProofGrader, can be used to compare a student's DFA with the correct DFA for a given language, thus greatly speeding up the grading of student assignments.
TWEAK–Fn14 as a mediator of acute kidney injury

Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) and its receptor, fibroblast growth factor-inducible 14 (TWEAK-Fn14), are widely expressed and are involved in both injury and repair. Hotta et al. now demonstrate an important role for Fn14 in the common clamp ischemia model of acute kidney injury. Their data suggest paracrine and autocrine effects in which TWEAK produced by tubule cells feeds back on them via upregulated Fn-14 receptors expressed downstream in the proximal tubule.
On the improperness sets of families of linear differential systems

We consider families of linear differential systems continuously depending on a real parameter with continuous (or piecewise continuous) coefficients on the half-line. The improperness set of such a family is defined as the set of all parameter values for which the corresponding systems in the family are Lyapunov improper. We show that a subset of the real axis is the improperness set of some family if and only if it is a Gδσ-set. The result remains valid for families in which the matrices of the systems are bounded on the half-line. Almost the same result holds for families in which the parameter occurs only as a factor multiplying the system matrix: their improperness sets are the Gδσ-sets not containing zero. For families of the last kind with bounded coefficient matrix, we show that their improperness set is an arbitrary open subset of the real line.
Candidate Competition and Attrition in Presidential Primaries, 1912-2000:

This article analyzes candidate competition and attrition in presidential primaries from 1912 to 2000. We use a modified market concentration index to measure the number of effective candidates entering presidential primaries and to calculate winnowing across presidential primaries. We test competing hypotheses about the increasing number of candidates entering primaries. We find that the number of effective candidates increased following the reforms of the 1970s. We reject the hypothesis that the number of candidates entering primaries increased gradually as a function of long-term factors. We also find similarities in the winnowing of candidates in each party during the prereform and postreform eras, which suggests the timing of candidate withdrawal owes to more than differences in each party’s delegate allocation rules. Republican presidential primaries more efficiently winnow candidates than do Democratic presidential primaries in both the prereform and postreform eras.
Transvestism in children

T ~ E term "transvestism" is applied to individuals who repeatedly dress up in the clothing of the opposite sex. I t has been observed throughout the ages and in all cultures. Though not infrequent in childhood, it is generally disregarded by pediatricians. Transvestism is to be distinguished from sexual inversion which is a much broader term and refers to "the identification with and adoption of the psychologic identity of the opposite sex. ''1 According to Brown, 1, 2 this process probably takes place unconsciously and early in life; only later, as the child matures, does he gradually come to consciously accept the deviant sex role as an integral part of himself. The term "homosexual," in connection with human behavior, is applied to sexual relations, either overt or psychic, between individuals of the same sex? The essential deviation is in the choice of a love object. Transvestism, sexual inversion, and homosexuality are independent phenomena. Much confusion is due to failure to keep this ,distinction dear ly in mind. Only a small percentage of adult transvestites are homosexual in their physical relationships. An excellent review of transvestism has recently been presented by Lukianowicz. 4
Molecular comparison of mouse Thy-1 and its human homologue.

Abstract Physicochemical techniques were used to verify previous immunochemical studies showing homology of the human Thy-1 (formerly p25) antigen and the murine Thy-1 or θ antigen. Peptide maps and amino acid compositions showed close similarity between these two proteins; however, they were not identical. These data confirm that the p25 antigen is the human homologue of mouse Thy-1.
FLORAL MORPHOLOGY AND CROSS‐POLLINATION IN ERYTHRONIUM GRANDIFLORUM (LILIACEAE)

In bumblebee visits to flowers of Erythronium grandiflorum (Liliaceae), the ratio of self- to nonself- ("outcross") pollen grains deposited on the stigma is positively correlated with the degree of stylar exsertion beyond the anthers. Natural populations show substantial, continuous
Human lymphotoxins: purification to electrophoretic homogeneity of the alpha H receptor-bearing class.

Abstract The au component (120–150,000 d) of the human LT system has been purified to electrophoretic homogeneity. This form was obtained from Con A-stimulated human tonsil and adenoid lymphocytes. Purification was greatly facilitated by employing a low concentration of lactalbumin hydrolysate as a serum substitute. The scheme consisted of sequential molecular sieving, lectin-affinity chromatography on Con A-Sepharose, and isoelectricfocusing. The specific activity of the αH increased approximately 5–10,000-fold in the course of purification, as judged by protein monitoring by the fluorescamine assay and radioiodination using the Iodogen technique. Homogeneity of the αH preparation from electrofocusing was demonstrated by native PAGE, as only a single protein peak was observed. The identity of this radioative peak with the lytic moiety was apparent as it migrated to the only region of the gel where lytic activity was detectable. This represents the third human lymphokine purified to homogeneity.