cssi/SciSciGPT-SciSciNet huggingface dataset:
Virtual matrix family: a new concept for getting 'extreme point' solutions in the robust stability analysis of interval parameter matrices

Elaborates on a concept called the virtual matrix family which played a pivotal role in getting an extreme point solution for checking the robust stability of interval matrices. In this paper, main differences between the virtual matrix family and the actual matrix family are clearly explained and the unique and important features of this concept and its role in getting an extreme point solution are presented in detail, thereby making the proof of the main theorems as clear and elaborate as possible. It is then pointed out that this new concept can be used for getting an extreme point solution for checking the robust stability of even polytopes of matrices.
Manganese: The Oxygen-Evolving Complex and Models

In this chapter, we give an overview of nature's singular biological process for producing dioxygen by the oxidation of water in photosynthetic organisms. The harnessing of light to accomplish the splitting of water was arguably nature's most successful experiment in biological innovation. It enabled global proliferation of oxygenic photosynthesis and created the biogeochemical cycles of oxygen and carbon on earth. We review the atomic structure of the metalloenzyme, the photosystem II water oxidation complex (PSII-WOC), as revealed by X-ray diffraction and spectroscopic techniques. We describe (i) the electronic and geometric structure of its inorganic core, Mn4CaO5, based upon spectroscopic and diffraction measurements; (ii) the organization of the protein subunits as revealed by X-ray diffraction and the role of select amino acid residues by site-directed mutagenesis; and (iii) the kinetics of the formation of light-induced intermediates, the exchange rates between substrate and free water molecules, the stoichiometry of electron and proton release, and the activation energies to discuss possible mechanisms for photosynthetic water splitting. The chemistry of photosynthetic water splitting is energetically demanding and mechanistically complex. The lessons learned from nature have guided chemists seeking to incorporate these design principles within catalysts suitable for abiotic water splitting. We end with a description of the few synthetic manganese complexes that have been found to produce oxygen from water and discuss the chemical mechanisms by which they appear to function. Keywords: bioinorganic chemistry; calcium; catalysis; manganese; oxygen evolution; photosynthesis; photosystem II; water splitting
Epigenetic modifications in frontal cortex from Alzheimer's disease and bipolar disorder patients

Alzheimer's disease (AD) and bipolar disorder (BD) are progressive brain disorders. Upregulated mRNA and protein levels of neuroinflammatory and arachidonic acid (AA) markers with loss of synaptic markers (synaptophysin and drebrin) have been reported in brain tissue from AD and BD patients. We hypothesized that some of these changes are associated with epigenetic modifications of relevant genes. To test this, we measured gene-specific CpG methylation, global DNA methylation and histone modifications in postmortem frontal cortex from BD (n=10) and AD (n=10) patients and respective age-matched controls (10 per group). AD and BD brains showed several epigenetic similarities, including global DNA hypermethylation, and histone H3 phosphorylation. These changes were associated with hypo- and hypermethylation of CpG islands in cyclooxygenase-2 and brain-derived neurotrophic factor promoter regions, respectively. Only the AD brain showed hyper- and hypomethylated CpG islands in promoter regions for cAMP response element-binding protein and nuclear transcription factor kappa B genes, respectively. Only the BD brain demonstrated increased global histone H3 acetylation and hypermethylation of the promotor region for the drebrin-like protein gene. There was no significant epigenetic modification for 12-lipooxygenase or p450 epoxygenase in either illness. Many observed epigenetic changes were inversely related to respective changes in mRNA and protein levels. These epigenetic modifications involving neuroinflammatory, AA cascade and synaptic markers may contribute to progression in AD and BD and identify new targets for drug development.
Two-frequency mutual coherence function of electromagnetic waves in atmospheric turbulence: A path integral variational solution

By use of path integral methods, a general expression is obtained for the two-frequency, two-position mutual coherence function of an electromagnetic pulse in turbulent atmosphere. This expression is valid for arbitrary models of refractive-index fluctuations, wide band pulses, and turbulence of arbitrary strength; it was examined for the case of Kolmogorov turbulence.
A practical support for ascending and descending paper chromatography

A single unit support, adaptable for use with all commercially available cylindrical chromatography jars, is described. The support is constructed of stainless steel and utilizes the expanding-collar principle. (M.C.G.)
Transformational Leadership, Cohesion Perceptions, and Employee Cynicism About Organizational Change The Mediating Role of Justice Perceptions

The impact of supervisors' transformational leadership (TFL), informational and interpersonal justice, and group cohesion perceptions on employee cynicism about organizational change (CAOC) was inv...
Is the iron law of oligarchy rusting away in the Third World

Abstract This article reexamines Robert Michels's iron law of oligarchy in relation to the proliferation of indigenous nongovernment organizations (NGOs) in the Third World in recent years. It explores the characteristics of grassroots organizations (GROs), horizontal networks between GROs, grassroots support organisations (GRSOs) and horizontal GRSO networks that reinforce democratic rather than oligarchic tendencies. Next it examines the vertical relationships between GROs and GRSOs that mitigate against interorganizational oligarchy. The article concludes that horizontal and vertical ties between NGOs reinforce the democratic characteristics of individual NGOs. The iron law, in other words, is not inevitable. This conclusion also has implications for international aid policies.
New mechanism of oral immunity to mucosal candidiasis in hyper-IgE syndrome

Oropharyngeal candidiasis (OPC, thrush) is an opportunistic infection caused by the commensal fungus Candida albicans. An understanding of immunity to Candida has recently begun to unfold with the identification of fungal pattern-recognition receptors such as C-type lectin receptors, which trigger protective T-helper (Th)17 responses in the mucosa. Hyper-IgE syndrome (HIES/Job's syndrome) is a rare congenital immunodeficiency characterized by dominant-negative mutations in signal transducer and activator of transcription 3, which is downstream of the Th17-inductive cytokines interleukin (IL)-6 and IL-23, and hence patients with HIES exhibit dramatic Th17 deficits. HIES patients develop oral and mucocutaneous candidiasis, supporting a protective role for Th17 cells in immunity to OPC. However, the Th17-dependent mechanisms of antifungal immunity in OPC are still poorly defined. An often unappreciated aspect of oral immunity is saliva, which is rich in antimicrobial proteins (AMPs) and exerts direct antifungal activity. In this study, we show that HIES patients show significant impairment in salivary AMPs, including β-defensin 2 and Histatins. This tightly correlates with reduced candidacidal activity of saliva and concomitantly elevated colonization with Candida. Moreover, IL-17 induces histatins in cultured salivary gland cells. This is the first demonstration that HIES is associated with defective salivary activity, and provides a mechanism for the severe susceptibility of these patients to OPC.
Conversion of 3, 4-dihydroxyphenylalanine and deuterated 3, 4-dihydroxyphenylalanine to alcoholic metabolites of catecholamines in rat brain

We have investigated the effects of 3, 4-dihydroxyphenylalanine (L-DOPA) and its deuterated analogue on the concentrations of alcoholic metabolites of catecholamines in rat brain by means of gas chromatography/mass spectrometry with selected-ion monitoring. Whole brain concentrations of the two neutral norepinephrine metabolites, 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) and 3, 4-dihydroxyphenylethyleneglycol (DHPG), were significantly increased in a dose-dependent manner by a single intraperitoneal injection of L-DOPA. Both MHPG and DHPG, as well as the corresponding dopamine metabolites, reached a maximum 1 h after injection. Brain MHPG and DHPG concentrations were elevated by 78 and 134%, respectively, 1 h after injection of 150 mg/kg L-DOPA. Analyses of discrete brain regions revealed that concentrations of the norepinephrine metabolites were elevated uniformly in all regions, except that MHPG showed a greater increase in the cerebellum than in other regions. The latter result appeared to be explained by the finding that 52% of the total MHPG in the cerebellum was unconjugated (compared to 15% in the whole brain). L-DOPA caused a proportionately greater increase in free MHPG than in total MHPG in the cerebellum and brain stem. By using deuterated L-DOPA in place of L-DOPA and measuring both the deuterated and nondeuterated norepinephrine metabolites, we demonstrated that virtually all of the increases in MHPG and DHPG were due to the conversion of the exogenous L-DOPA to norepinephrine. Thus, the effects of norepinephrine metabolism need to be considered in attempts to understand clinical and behavioral effects of L-DOPA.
Prenatal Cocaine Exposure: Drug and Environmental Effects at 9 Years

Objective To assess school-age cognitive and achievement outcomes in children with prenatal cocaine exposure, controlling for confounding drug and environmental factors. Study design At age 9 years, 371 children (192 cocaine exposure [CE]; 179 non–cocaine exposure [NCE]) were assessed for IQ and school achievement in a longitudinal, prospective study from birth. An extensive number of confounding variables were controlled, including quality of caregiving environment, polydrug exposure, blood lead level, iron-deficiency anemia (IDA), and foster/adoptive care. Results Prenatal cocaine exposure predicted poorer perceptual reasoning IQ, with a linear relationship of the concentration of the cocaine metabolite benzoylecgonine to the degree of impairment. Effects were mediated through birth head circumference, indicating a relationship with fetal brain growth. Negative effects of alcohol, lead, and marijuana exposure and positive effects of the home environment were additive. The CE children in foster/adoptive care had better home environments and lower lead levels. School achievement was not affected. Conclusions Persistent teratologic effects of CE on specific cognitive functions and additive effects of alcohol, lead, and marijuana exposure; IDA; and the home environment were identified. Documenting environmental factors in behavioral teratology studies is important, because in this sample, CE was associated with better home environment and lower environmental risk in a substantial number of children.
Promoting the moral reasoning of undergraduate business students through a deliberate psychological education-based classroom intervention

Educating business students for ethical professional practice is a growing concern for both the corporate world and business education. Highly publicised scandals have pushed public trust in business to an all‐time low, resulting in losses of customers and high employee turnover. Corporate and business education leaders have begun to press for more effective models for promoting ethical development in business education. This study examined the effectiveness of one such model, Deliberate Psychological Education (DPE), in promoting greater cognitive moral reasoning in undergraduate business students. Its significant, positive findings hold promise for the promotion of more ethical business professionals through preparatory classroom intervention.
Adolescents' formal employment and school enrollment: Effects of state welfare policies

Variations in state welfare policies in the reform era may affect adolescents through two mechanisms: A competing labor market hypothesis posits that stringent state welfare policies may reduce adolescent employment; and a signaling hypothesis posits that stringent welfare policies may promote enrollment. To test these hypotheses, we use a dynamic joint model of adolescents' school enrollment and formal employment, separating state welfare policies from non-welfare state policies, state labor market conditions, and unobserved state characteristics. Longitudinal data from the NLSY97 on adolescents aged 14 to 18 and various state data sources over the period 1994–1999 support the competing labor market effect but not the signaling effect. In particular, lower-income dropouts suffer more severely from fewer labor market opportunities when state welfare policies are more stringent, which indicates that welfare reform may compromise work opportunities for lower-income dropouts. © 2004 by the Association for Public Policy Analysis and Management.
Ca2+-Triggered Simultaneous Membrane Penetration of the Tandem C2-Domains of Synaptotagmin I

Synaptotagmin I (syt), a transmembrane protein localized to secretory vesicles, functions as a Ca2+ sensor that facilitates SNARE-mediated membrane fusion. The cytoplasmic domain of syt harbors two C2-domains designated C2A and C2B. Upon binding Ca2+, C2A and C2B partially penetrate into membranes that contain anionic phospholipids. However, it is unknown whether these tandem C2-domains engage membranes at the same time, in a sequential manner, or in a mutually exclusive manner. We have used site-directed fluorescent probes to monitor the penetration of syt's C2-domains into phosphatidylserine-harboring lipid bilayers. We report that, in response to Ca2+, C2A and C2B copenetrate into these bilayers with diffusion-limited kinetics. Membrane penetration was more efficient when synthetic rather than natural phospholipids were used to prepare bilayers. The membrane penetration activity of the intact cytoplasmic domain of syt (C2A-C2B) exhibits significant resistance to changes in ionic strength. In contrast, the ability of isolated C2B to bind membranes in response to Ca2+ can be disrupted by subtle changes in ionic strength. Tethering C2B to a mutant version of C2A that does not bind Ca2+ or membranes significantly increases the stability of Ca2+·C2B·membrane complexes, confirming that C2A affects the membrane-binding properties of the adjacent C2B domain.
Evaluating distances using a coded lens camera and a blur metric

We propose a method and a system to measure distances to a target and at the same time obtaining an image of the target. The system is based on a wavefront coded lens and an image processing unit. The method requires a calibration phase where a blur metric is related to the distance of the target. The distance to the target for any position is then obtained by computing the blur metric of the target and using the calibration data. The method and system are easy to manufacture and provide an alternative to other distance measuring methods and devices, while also producing an image of the scene. The target is a printed image of pseudo random black and white elements which can be stick or placed nearby objects of which distance is to be evaluated.
A random walk: Based model for identifying semantic orientation

Automatically identifying the sentiment polarity of words is a very important task that has been used as the essential building block of many natural language processing systems such as text classification, text filtering, product review analysis, survey response analysis, and on-line discussion mining. We propose a method for identifying the sentiment polarity of words that applies a Markov random walk model to a large word relatedness graph, and produces a polarity estimate for any given word. The model can accurately and quickly assign a polarity sign and magnitude to any word. It can be used both in a semi-supervised setting where a training set of labeled words is used, and in a weakly supervised setting where only a handful of seed words is used to define the two polarity classes. The method is experimentally tested using a gold standard set of positive and negative words from the General Inquirer lexicon. We also show how our method can be used for three-way classification which identifies neutral words in addition to positive and negative words. Our experiments show that the proposed method outperforms the state-of-the-art methods in the semi-supervised setting and is comparable to the best reported values in the weakly supervised setting. In addition, the proposed method is faster and does not need a large corpus. We also present extensions of our methods for identifying the polarity of foreign words and out-of-vocabulary words.
Analysis of Risk Factors for Patient and Renal Survival in Crescentic Glomerulonephritis

A series of 57 patients with crescentic glomerulonephritis was studied retrospectively to estimate patient and renal survival and to analyze the variables that affect these end points. Renal survival was 47% at 6 months for patients with idiopathic rapidly progressive glomerulonephritis and 33% for patients with antiglomerular basement membrane disease. Most patients in these two groups presented with advanced renal insufficiency. Renal survival rates for patients with systemic illness, with or without a tissue diagnosis of vasculitis, were 93% and 100%, respectively, at 1 year. These patients had better renal function at presentation. Overall, patient survival at 5 years was 61%, and there were no significant differences among the groups. A systematic analysis of clinical, immunopathologic, and laboratory variables showed that the initial serum creatinine level and oliguria and the patient's age and oliguria were the most important indicators of renal and patient survival, respectively. Virtually all patients with a creatinine level > 6.0 mgldL lost their kidneys. Five-year survival for patients > 60 years old was 31%, compared with 83% for those ≤ 60 years. Moderate-to-severe tubulointerstitial inflammation indicated worse patient and renal survival, and 24-hour urine protein excretion > 3 g was related to shorter renal survival. We have identified and ranked a number of variables that affect patient or renal survival in crescentic glomerulonephritis. These findings may be of help in the decision-making process of patient management and analysis of treatment modalities.
Computations of Air/Fuel Preparation Process in a Port-Injected Spark-Ignition Engine During Cold-Starting Phase

A numerical study has been performed of the air/fuel preparation process in a cold-starting port-injected spark-ignition engine. The latest models were implemented for spray impingement and multicomponent vaporization of the droplet and wall film accounting for finite diffusion in the liquid. The infinite diffusion model was found insufficient for predicting vaporization in this engine, and the single-component fuel representation yields results significantly different from those from the multicomponent one. The operating parameters studied included injection timing, swirl, speed, target path, enrichment, and fuel accumulation. In-cylinder measurements were compared and good agreement was achieved. Detailed quantitative analysis of the air/fuel preparation of the engine was reported.
Eliciting critical literacy narratives of bi/multilingual teacher candidates across U.S. teacher education contexts

Abstract This paper examines critical literacy narratives of bi/multilingual preservice teachers across contexts in the United States. It draws upon empirical data from two studies—a narrative inquiry with Latino teacher candidates in the Midwest and a participatory action research project with bilingual preservice teachers in Hawaii—to examine participants’ identities and experience in academia. Preservice teachers in both studies resisted the labeling practice of “minority” and challenged simplistic notions of “bilingual teacher identity.” This cross-examination argues for further ways to explore how teacher preparation programs should create dialogic spaces for making the voices of diverse preservice teachers heard.
Effectiveness of the Transoral Endoscopic Vertical Gastroplasty (TOGa®): a Good Balance Between Weight Loss and Complications, if Compared with Gastric Bypass and Biliopancreatic Diversion

Background The effectiveness of restrictive procedures has been inferior to that of malabsorbitive ones. Recent variants of restrictive procedures, i.e., gastric banding and sleeve gastrectomy, confirm the strive for more efficacious solutions with less complications. We investigated the balance between effectiveness and complications for a new restrictive procedure, a Transoral Endoscopic Vertical Gastroplasty (TOGa®)
A kinetic study of the reaction of NO2 with HI over the temperature range 278 to 333 K

The rate constant, k, for the reaction, NO2 + HI → products, has been measured directly for the first time. The rate was found to be − d[NO2]/dt = k[NO2][HI] with k = (6.9 ± 1.1) × 10−19 cm3 molecule−1 s−1 at 303 K. The measurements were made under pseudo-first-order conditions with HI in excess over NO2. NO2 loss rate was monitored by FTIR in a static glass reactor. NO, H2O and I2 were observed as products and HNO2 as an intermediate. The study showed that the reaction was influenced by the conditions of the wall which had a surface loss rate constant kw = 0.13 s−1. This indicates that the measured k is an upper limit. Within a limited pressure range, the rate was independent of the total pressure in the system. From measurements made over the temperature range 278–333 K, we obtained the following expression for k = (3.6 ± 0.2) × 10−14 × exp[ − (2.7 ± 0.7) × 104/RT] cm3 molecule−1 s−1 valid between 293 and 333 K. A reaction scheme is proposed involving as the initiation step based on the kinetic and product studies, followed by a heterogeneous reaction between HNO2 and HI. A comparison of the reactions between NO2 with HX is made. This reaction is unlikely to play a major role in the removal of HI and as a source for HNO2 in the atmosphere because of its slow rate.
Heterogeneous Conditional Random Field: Realizing joint detection and segmentation of cell regions in microscopic images

Detecting and segmenting cell regions in microscopic images is a challenging task, because cells typically do not have rich features, and their shapes and appearances are highly irregular and flexible. Furthermore, cells often form clusters, rendering the existing joint detection and segmentation algorithms unable to segment out individual cells. We address these difficulties by proposing a Heterogeneous Conditional Random Field (HCRF), in which different nodes have different state sets. The state sets are designed in such a way that the resulting HCRF model could encode all possible detection/segmentation cases while keeping its identifiability and compactness. Attributed to the provably optimal design of the state sets, the proposed model successfully realizes joint detection and segmentation of the cell regions into individual cells whether the cells are separate or touch one another. Experiments on two different types of cell images show that the HCRF outperforms several recently proposed methods.
The Association Between Parenting Stress, Parenting Self-Efficacy, and the Clinical Significance of Child ADHD Symptom Change Following Behavior Therapy

We examined parenting stress (PST) and self-efficacy (PSE) following participation in behavioral parent training (BPT) with regard to child treatment response. Forty-three families of children diagnosed with ADHD participated in a modified BPT program. Change in PST and PSE was evaluated using a single group, within-subjects design. Parenting outcomes based on child treatment response were evaluated based upon (1) magnitude and (2) clinical significance of change in child symptom impairment. Parents reported significant improvements in stress and self-efficacy. Parents of children who demonstrated clinically significant reduction in ADHD symptoms reported lower stress and higher self-efficacy than those of children with continued impairments. Magnitude of child impairment was not associated with parent outcomes. Clinical implications for these results include extending treatment duration to provide more time for symptom amelioration and parent-focused objectives to improve coping and stress management.
Visual and auditory input in second-language speech processing

The majority of studies in second-language (L2) speech processing have involved unimodal (i.e., auditory) input; however, in many instances, speech communication involves both visual and auditory sources of information. Some researchers have argued that multimodal speech is the primary mode of speech perception (e.g., Rosenblum 2005). Research on auditory-visual (AV) input has been conducted more extensively in the fields of infant speech development (e.g., Meltzoff & Kuhl 1994), adult monolingual processing (e.g., McGurk & MacDonald 1976; see reference in this timeline), and the treatment of the hearing impaired (e.g., Owens & Blazek 1985) than in L2 speech processing (Hardison 2007). In these fields, the earliest visual input was a human face on which lip movements contributed linguistic information. Subsequent research expanded the types of visual sources to include computer-animated faces or talking heads (e.g., Massaro 1998), hand-arm gestures (Gullberg 2006), and various types of electronic visual displays such as those for pitch (Chun, Hardison & Pennington 2008). Recently, neurophysiological research has shed light on the neural processing of language input, providing another direction researchers have begun to explore in L2 processing (Perani & Abutalebi 2005).
Search costs and the quit rate

Abstract In a simple model of job search with belated information, we show that an increase in search costs decreases the expected probability of a quit, if the wage offer distribution possesses a monotonically increasing hazard rate property. The model is then applied to a marital search.
Quadratic differentials and foliations

This paper concerns the interplay between the complex structure of a Riemann surface and the essentially Euclidean geometry induced by a quadratic differential. One aspect of this geometry is the " trajectory structure" of a quadratic differential which has long played a central role in Teichmfiller theory starting with Teichmiiller's proof of the existence and uniqueness of extremal maps. Ahlfors and Bers later gave proofs of that result. In other contexts, Jenkins and Strebel have studied quadratic differentials with closed trajectories. Starting from the dynamical problem of studying diffeomorphisms on a C ~ surface M, Thurston [17] invented measured ]ol~t io~. These are foliations with certain kinds of singularities and an invariantly defined transverse measure. A precise definition is given in Chapter I, w 1. This notion turns out to be the correct abstraction of the trajectory structure and metric induced by a quadratic differential. In this language our main statement says that given any measured ]oliation F on M and any complex structure X on M, there is a unique quadratic diHerential on the Riemann surface X whose horizontal trajectory structure realizes F. In particular any trajectory structure on one Riemann surface occurs uniquely on every Riemann surface of that genus. In the special case when the foliation has closed leaves, an analogous theorem was proved by Strebel [15]. Earlier Jenkins [13] had proved that quadratic differentials with closed trajectories existed as solutions of certain extremal problems. We deduce Strebel's theorem from ours in Chapter I, w 3. By identifying the space of measured foliations with the quadratic forms on a fixed Riemann surface, we are able to give an analytic and entirely different proof of a result of Thurston's [17]; that the space of projective classes of measured foliations is homeomorphic to a sphere. This is also done in Chapter I, w 3.
Compactness and connectedness as composable properties

In [5] Magill showed that compactness is a composable property of Hausdorff spaces. (That is, if α,β are compact subsets of X × X , then α ○ β is also compact when X is T 2 .) Also Magill gave an example to show that the composition of connected relations need not be connected. Subsequently, he characterized Hausdorff k-spaces in terms of the semigroup of compact relations in X .
Power of fast VLSI models is insensitive to wires' thinness

VLSI f-models which allow the switching time to decrease to f(D) when the length of all wires is restricted by D are called 'fast' if the decrease is slightly superlinear. The fast models are so strong and robust that their computational power cannot be increased by and combination of the following: (1) making zero the width of each wire of length d, except for its log d segment, thus eliminating layout and area considerations; (2) allowing wires to transmit log d bits simultaneously; (3) making the switching time f(d) of each node depend only on the length d of its own input wires, thus enabling small subcircuits to run faster; (4) changing f while preserving Sigma /sub k/ 1/f(k); (5) enabling the nodes to change connections arbitrarily in the run time. The authors construct a kind of operating system link server (linx, for short) that simulates all these powers online. The condition of superlinearity cannot be weakened. >
Algorithms for defects in nanostructures

Abstract We illustrate recent progress in developing algorithms for solving the Kohn–Sham problem. Key ingredients of our algorithm include pseudopotentials implemented on a real space grid and the use of damped-Chebyshev polynomial filtered subspace iteration. This procedure allows one to predict electronic properties for many materials across the nano-regime, i.e., from atoms to nanocrystals of sufficient size to replicate bulk properties. We will illustrate this method for large silicon quantum dots doped with phosphorus defect.
The Raman-active continuum in high temperature superconductors and its interactions with phonons

Abstract At temperatures above T c the Raman spectrum from single crystals of YBCO and BiSrCCO contains a strong, essentially structureless, continuum that extends from ω=0 to ω>1000's of cm −1 . In YBCCO this continuum shows an anti-resonance with the 330 cm −1 mode (anti-phase, axial motions of planar O's) and the 115 cm −1 mode (axial Ba). The temperature-dependences of the continuum and of these phonon modes are compared and possible origins of the continuum discussed.
Human DNA topoisomerase II-alpha: a new marker of cell proliferation in invasive breast cancer

DNA topoisomerase II-alpha is the molecular target of doxorubicin, an active drug used in the therapy of breast cancer. From many in vitro studies, it is known that high levels of topo II-alpha expression correlate with drug sensitivity, and low levels of topo II-alpha correlate with drug resistance. In addition, the enzyme is known to be a marker of cell proliferation in normal tissues. Because the number of proliferating cells in a breast cancer has been shown to be prognostically important, and because doxorubicin is used in the treatment of breast cancer, we hypothesized that the measurement of topo II-alpha in breast cancer may not only give drug sensitivity information but also may yield important data on cell proliferation. In this study, formalin-fixed, paraffin-embedded tissue from 30 specimens of invasive breast cancer from 20 patients were immunohistochemically stained for topo II-alpha with a mouse monoclonal antibody. For each case, a topo II-alpha index was determined that represents the number of positive-staining tumor cells divided by the total number of tumor cells counted times 100. A similar index was determined for MIB1, a known cell proliferation marker. Each case was also graded according to the modified Bloom-Richardson criteria and evaluated for c-erbB-2 amplification, hormonal status, S-phase fraction, and mitotic index. The topo II-alpha index correlates better with the MIB1 index than with the S-phase fraction or mitotic index. The topo II-alpha expression in breast cancer ranges from low (topo II-alpha index <1) to high (topo II-alpha index = 86). Amplification of c-erbB-2 was observed in 4 of 28 cases (14%) but did not correlate with high topo II-alpha indices. We conclude that measurement of topo II-alpha in invasive breast cancer can be readily performed by immunohistochemical staining, and it gives information on the number of cycling tumor cells. In addition, because the enzyme is the molecular target of doxorubicin, the expression of the enzyme may relate also to the sensitivity or resistance of the tumor to doxorubicin-based chemotherapeutic protocols.
Bioactive glass-ceramic: formation, characterization and bioactivity

Abstract A new bioactive glass-ceramic with the nominal composition CaO (54.5), MgO (6.0), SiO2 (32.8), P2O5 (6.1) and CaF2 (0.6) (in wt.%) has been developed. Crystalline phases, termed akermanite, wollastonite and apatite, were found to precipitate simultaneously at temperatures between 930 and 1150 °C. No cracks appear in the glassceramic after crystallization. This new type of glass-ceramic demonstrates a flexural strength of 233 MPa and a fracture toughness of 2.95 MPa m 1 2 , which are higher than those of dense hydroxyapatite and other well-known bioactive materials. The glass-ceramic exhibits a high bioactivity in vitro. The occurrence and recombination of surface cracks in the material can be observed when it is immersed in a simulated bodily fluid (SBF) for sufficient periods, and this can be explained in terms of a self-healing mechanism. The mechanism of apatite formation onto the surface of the glass-ceramic is discussed.
University and Work Organization Influences on Professional Role Orientation

Abstract The relative importance of university versus work setting socialization experiences and the combined effects of these experiences on professional role orientation is assessed via path analysis for a sample of 1580 engineering and science graduates of a large midwestern university. As hypothesized, the following experiences positively effect professional role orientation: science training; attainment of the Ph.D.; autonomy as a graduate student; knowledge of faculty who endorse the scientific ethos; assignment to an R&D function and exercise of high levels of technical responsibility in initial and current jobs. In general, professional orientation results less from work setting influences than from graudate school training. One exception is that respondents who exercise high levels of technical responsibility in 1965 show a stronger professional orientation than their less successful colleagues.
Sex steroid levels across the reproductive cycle of female leopard geckos, Eublepharis macularius, from different incubation temperatures.

Incubation temperature during embryonic development determines gonadal sex in many reptiles, including the leopard gecko (Eublepharis macularius). In this study, we examined the hormonal and behavioral changes that occur during the reproductive cycle of female leopard geckos from four (i.e., 26, 30, 32.5, and 34 degrees C) incubation temperatures. Controlling for reproductive status, plasma levels of dihydrotestosterone (DHT), testosterone (T), and progesterone (P) varied with incubation temperature but estradiol 17-beta (E2) levels did not. Controlling for the effects of incubation temperature, DHT and T levels were low when females were previtellogenic, increased slightly during early vitellogenesis, increased dramatically during late vitellogenesis (i.e., prior to ovulation), and then decreased to previtellogenic levels after ovulation. In contrast, E2 levels increased gradually from the previtellogenic stage to the early vitellogenic stage, peaked during late vitellogenesis, and decreased to previtellogenic levels after ovulation. Levels of P increased from the previtellogenic stage to the early vitellogenic stage, remained elevated during late vitellogenesis, and then decreased after ovulation. Moreover, we determined that females were not sexually receptive when previtellogenic, were somewhat receptive during early vitellogenesis (approximately 20% receptive), were most receptive during late vitellogenesis (approximately 80% receptive), and were again unreceptive after ovulation. Incubation temperature did not influence receptivity. Overall, these data show that hormone levels and behavior change coordinately during the reproductive cycle. Although incubation temperature has persistent effects on endocrine physiology in adult female leopard geckos, these effects are modest compared to hormonal changes across the reproductive cycle.
Values Clarification as Indoctrination

(1977). Values Clarification as Indoctrination. The Educational Forum: Vol. 41, No. 2, pp. 155-165.
A Survey of North American Burn and Plastic Surgeons on Their Current Attitudes Toward Facial Transplantation

BACKGROUND: Feasibility of composite tissue allotransplantation (CTA) has been substantiated by transplantations of the hand, abdominal wall, and face. CTA has the potential to reconstruct "like with like," but the risk-to-benefit ratio and clinical indications have yet to be determined. We sought to examine the current attitudes about the emerging field of CTA from those who treat complex facial injuries. STUDY DESIGN: In 2007, a Web-based blinded survey was sent to both burn and plastic surgeons involved in facial reconstruction. We examined the practice profile with regard to complex facial injuries and asked respondents to assess the level of risk in CTA and indications for facial transplantation. Surgeons were asked to evaluate three clinical cases (two closely mirroring clinical face transplantations) for suitability for treatment with CTA. RESULTS: One hundred sixty-four surgeons responded (54% response rate) and averaged 17.3 years in practice. They saw 12.1 severe facial-injury patients per year. A total of 78.7% agreed that current techniques do not provide adequate reconstruction for severe facial injuries, and 26.2% were in favor of performing CTA on immunosuppression. Acceptable indications for CTA were multiple failed reconstructions (70%), total facial burn (59%), and absence of remote tissue (55%). Ten percent saw no acceptable indication for CTA. The scenarios that mimicked recent transplantations had moderate support in favor of CTA (20.7% for the Chinese patient and 29.3% for the French patient). CONCLUSIONS: This survey demonstrates support for use of CTA to reconstruct complex facial deformities. Surgeons continue to be wary of immunosuppression and chronic rejection, and many want to wait for better immunologic treatment options.
Visual classification of very fine-grained sediments: evaluation through univariate and multivariate statistics

Classifying very fine-grained rocks through fabric elements provides information about depositional environments, but is subject to the biases of visual taxonomy. To evaluate the statistical significance of an empirical classification of very fine-grained rocks, samples from Devonian shales in four cored wells in West Virginia and Virginia were measured for 15 variables: quartz, illite, pyrite and expandable clays determined by X-ray diffraction; total sulfur, organic content, inorganic carbon, matrix density, bulk density, porosity, silt, as well as density, sonic travel time, resistivity, and γ-ray response measured from well logs. The four lithologic types comprised: (1) sharply banded shale, (2) thinly laminated shale, (3) lenticularly laminated shale, and (4) nonbanded shale. Univariate and multivariate analyses of variance showed that the lithologic classification reflects significant differences for the variables measured, difference that can be detected independently of stratigraphic effects. Little-known statistical methods found useful in this work included: the multivariate analysis of variance with more than one effect, simultaneous plotting of samples and variables on canonical variates, and the use of parametric ANOVA and MANOVA on ranked data.
Smoothly mixing regressions

This paper extends the conventional Bayesian mixture of normals model by permitting state probabilities to depend on observed covariates. The dependence is captured by a simple multinomial probit model. A conventional and rapidly mixing MCMC algorithm provides access to the posterior distribution at modest computational cost. This model is competitive with existing econometric models, as documented in the paper's illustrations. The first illustration studies quantiles of the distribution of earnings of men conditional on age and education, and shows that smoothly mixing regressions are an attractive alternative to nonBayesian quantile regression. The second illustration models serial dependence in the S&P 500 return, and shows that the model compares favorably with ARCH models using out of sample likelihood criteria.
Dosimetric and radiographic correlates to prostate brachytherapy‐related rectal complications

Despite rates of radiation proctitis reported in the 1% to 9% range in most series, there is little information regarding rectal morbidity and dosimetric parameters. Accordingly, we have analyzed computed tomography (CT)-based dosimetric parameters based on a series of patients with endoscopically proven radiation proctitis. Nine patients diagnosed with radiation proctitis on endoscopy were identified in a prior review of 160 consecutively treated patients at the University of Washington in 1997. For each proctitis patient, two patients with no rectal bleeding matched for prostate size, isotope, and dose were selected as controls. Axial CT images obtained 2 to 4 hour postoperatively were used for postimplant dosimetry. Dose volume histograms of the rectum, surface area of the outer rectal wall receiving ≥ 100% of the prescribed dose, maximum rectal dose, and length of rectum receiving ≥ 100% prescription were obtained. Preimplant CT scans were used to group patients into three categories based on the amount of apparent rectal contact with the prostate. All rectal dosimetric parameters were statistically different between patients with or without rectal bleeding. The mean surface area receiving at least 100% prescription dose was 3.1 cm2 for the controls vs. 6.9 cm2 for the rectal bleeders (P = 0.001). The volume of rectum receiving at least 100% of prescription dose was 0.6 cc for the controls vs. 2.5 cc for the bleeders (P = 0.00008). Patients with full prostate-rectal contact had significantly higher rectal dose parameters compared to those with partial or no rectal contact. All nine proctitis patients were in the full-rectal-contact group compared to only seven of 18 (39%) controls. This detailed dosimetric analysis shows higher rectal doses for patients with radiation proctitis, making it a potential method of identifying patients at higher risk for receiving excessive rectal doses based on the anatomic relationship between the rectum and prostate on CT scan. Published 2001 Wiley-Liss, Inc.
Cluster of Differentiation 44 Targeted Hyaluronic Acid Based Nanoparticles for MDR1 siRNA Delivery to Overcome Drug Resistance in Ovarian Cancer

Purpose Approaches for the synthesis of biomaterials to facilitate the delivery of “biologics” is a major area of research in cancer therapy. Here we designed and characterized a hyaluronic acid (HA) based self-assembling nanoparticles that can target CD44 receptors overexpressed on multidrug resistance (MDR) ovarian cancer. The nanoparticle system is composed of HA-poly(ethyleneimine)/HA-poly(ethylene glycol) (HA-PEI/HA-PEG) designed to deliver MDR1 siRNA for the treatment of MDR in an ovarian cancer model.
Hierarchical Markov Chain Monte Carlo Simulation for Modeling Transverse Cracks in Highway Pavements

Transverse cracks are distresses whose initiation and propagation affect the stability and structural integrity of the highway pavement. They are caused by load, moisture, temperature, construction defects, or a combination of these. Cracking leads to inherent pavement defects that are exacerbated by moisture infiltration as well as the formation of other pavement distresses like roughness with their attendant problems to roadway agencies and users. One feature of transverse cracks is the spontaneity of their initiation and the uncertainty of their propagation. As a result, modeling the formation and spread of transverse cracks requires a framework within which uncertainty can be expressed explicitly. This research seeks to use a statistical approach to model the propagation of transverse cracks on road pavements in Delaware. The aim is to investigate how hierarchical Markov-chain Monte Carlo (MCMC) simulation performs in estimating and predicting the spread of transverse cracks without neglecting their associated uncertainty. Hierarchical MCMC models use the Bayesian approach, which accounts for uncertainty in pavement distresses.
The electronic properties of disordered passive films

The understanding of passivity and its role in corrosion research is closely connected with the electronic properties of passive films. The approach of describing passive films in terms of their semiconducting properties can be improved by using models developed for amorphous semiconductors where localized electronic states play an important role. It is shown that localized states in passive films are of importance for the photo-electrochemical behavior where it expresses itself in sub-band gap photocurrents and a potential dependence of the photocurrent according to the Poole-Frenkel effect. Non-linear Schottky-Mott plots resulting from capacity data can be attributed to bulk localized states in the band gap and can thus be used to characterize highly disordered and/or non-stoichiometric passive films. The use of a photo-electrochemical laser scanning technique for the in-situ imaging of passivated surfaces and of corroding surfaces is also shown.
Commentary: what role should physician organizations play in addressing social justice issues?

A study by Peek and colleagues in this issue reveals that although racial and ethnic health disparities are recognized as a major national challenge, few physician organizations with both the influence and ability to change practice standards and address disparities appear to be effectively directing their resources to mitigate health disparities. In this commentary, the author examines the history of U.S. health disparities through the lens of social justice. He argues that today, physician organizations have the opportunity to change the paradigm of medicine from being a reactive industry to becoming a proactive industry through collaborations such as the Commission to End Health Disparities, which brings together more than 60 organizations, and the National Medical Association's "We Stand With You" program to improve health and combat disparities. Physician organizations can also address health disparities through advocacy for fair reimbursement policies, funding for pipeline programs to increase the diversity of the workforce, diversity in clinical trials, and other issues. Health disparities present to us in organized medicine a challenge that is cleverly disguised as an immovable object but that is truly a great opportunity for innovation, improvement, and growth. Physician organizations have a unique opportunity to provide avenues of innovation and accomplishment.
On crack closure and the notch size effect in fatigue

Abstract A method for determining the fatigue notch-size-effect is presented based upon the development of closure in the wake of a newly formed crack growing from a notch. A comparison with experimental results is in accord with predictions. The effect of crack closure on the formation of non-propagating cracks at notches and on notch sensitivity is also discussed.