cssi/SciSciGPT-SciSciNet huggingface dataset:
An interparticle force model for ac–dc electric fields in powders

Abstract An interparticle force model is presented for ac–dc current flow in a semi-insulating powder. The model applies to contacting particles as in packed and fluidized beds as well as to particle stringers. The electrostatic model is based on simple lumped parameter circuit theory and correctly predicts the field–frequency trend observed for decreased bubble formation and increased bed height in a fluidized bed. Particle–particle and self-particle electrostatic interactions give two characteristic time constants resulting from the resistance–capacitance effects. The time constants are interpreted from single-particle and continuum relaxation theories. A second empirical force equation is presented by curve-fitting data over variable frequency and field strength for the demarcation between a frozen and fluidized bed. The two force models (theory and empirical) are shown to be of the same form in field–frequency dependence and predict bulk relaxation times that are comparable in magnitude. Numerical estimates for the time constants and other parameters for the powder bed are given.
A medical outreach elective course.

To the Editor. The article by Perry et al presents a very vital aspect of pharmacy education that addresses the care for people who are underserved.1 They describe an elective that provides valuable student opportunities, including an international medical outreach trip that fits within the Accreditation Council for Pharmacy Education (ACPE) guidelines. However, the expenses of an international medical outreach trip may deter interested students from taking this elective, as deter colleges and schools of pharmacy from adopting the elective. Colleges and schools that are thinking about implementing a curriculum in medical outreach should consider local opportunities in which the same goals, objectives, and changes in student perceptions can be achieved. As a recent pharmacy school graduate who has been on both local and international medical outreach trips, I can relate to the positive impact they have had of bringing a different perspective of providing patient care and working in an interdisciplinary team. Unfortunately, international outreach trips can be very costly. Students from this course spent approximately $2,500.1 However, there are a variety of local medical outreach experiences available where students can receive similar experiences with less financial burden. During my last year in pharmacy school, I volunteered with a nonprofit group called Remote Area Medical that provides free comprehensive health care to people in remote areas of the United States.2 In 1 weekend, I was able to provide care to hundreds of people who had been lined up for days to receive the only health care they would receive all year. This local medical outreach provided an equally valuable experience compared to the international medical trip that I took, but with minimal costs. In the words of author Marianne Williamson, “In every community there is work to be done. In every nation there are wounds to heal. In every heart there is the power to do it.”
Distinct roles of age and abdominal visceral fat in reducing androgen receptor‐dependent negative feedback on LH secretion in healthy men

Testosterone (T) impacts luteinizing hormone (LH) secretion through negative feedback via the androgen receptor (AR) in the hypothalamo-pituitary system. An untested postulate is that increasing body mass index (BMI), abdominal visceral fat (AVF) or total abdominal fat (TAF) with ageing decreases LH secretion by heightening T negative feedback via AR. This hypothesis was tested in a prospective, randomized double-blind cross-over study of 19 healthy men comparing the effects of flutamide, a selective non-steroidal AR antagonist and placebo administration on basal and pulsatile LH secretion as a function of age and obesity measures. To this end, serum levels of 2-hydroxyflutamide (2-OHF), a major active flutamide metabolite, were measured by mass spectrometry, and AVF/TAF quantified by abdominal computerized tomography. Statistical analysis showed that antiandrogen administration elevated 6-h mean LH concentrations to 5.4 ± 1.3 IU/L compared with 3.3 ± 1.2 IU/L for placebo (p < 10(-3) ), and total T by 35% (p < 10(-4) ). The LH-T concentration product doubled (p < 10(-8) ). According to deconvolution analysis, flutamide exposure increased total LH secretion (p < 10(-3) ) and pulsatile LH secretion (p = 0.0077), along with LH pulse frequency (p = 0.019). Despite feedback inhibition, the LH-T product declined as a linear function of AVF (p = 0.021) and TAF (p = 0.017). This was explained by the fact that higher BMI was associated with lower 2-OHF concentrations (R = -0.562, p = 0.012). In contrast, age was associated with less pulsatile LH secretion (R = -0.567, p = 0.011) even when LH responses were normalized to antiantrogen levels. In conclusion, increased AVF, TAF and BMI predict decreased LH and flutamide blood levels, whereas older age is marked by impaired stimulation of pulsatile LH secretion even when normalized for antiandrogen levels, suggesting different mechanisms of regulation by adiposity and age.
In vivo and in vitro measurements of pulmonary arterial stiffness: A brief review.

AbstractDuring the progression of pulmonary hypertension (PH), proximal pulmonary arteries (PAs) undergo remodeling such that they become thicker and the elastic modulus increases. Both of these changes increase the vascular stiffness. The increase in pulmonary vascular stiffness contributes to increased right ventricular (RV) afterload, which causes RV hypertrophy and eventually failure. Studies have found that proximal PA stiffness or its inverse, compliance, is strongly related to morbidity and mortality in patients with PH. Therefore, accurate in vivo measurement of PA stiffness is useful for prognoses in patients with PH. It is also important to understand the structural changes in PAs that occur with PH that are responsible for stiffening. Here, we briefly review the most common parameters used to quantify stiffness and in vivo and in vitro methods for measuring PA stiffness in human and animal models. For in vivo approaches, we review invasive and noninvasive approaches that are based on measuremen...
Effect of growth parameters on compositional variations in directionally solidified HgCdTe alloys

A series of Hg(1-x)Cd(x)Te alloy crystals was grown by directional solidification with compositions ranging from x = 0.2 to x = 0.4. The measured axial compositional profiles were interpreted in terms of an exact numerical solution of the appropriate diffusion equation that takes into account both the variations of the segregation coefficient and solidification rate with composition. The solutions for all growth rates agree generally well with the experimental data, and confirm earlier observations that employed approximate analytical solutions. The effective mass diffusion coefficients showed no significant composition or melt temperature dependence. Slightly higher diffusion coefficients were obtained, however, for the highest growth rates.
Choreoballismus: A nonhemorrhagic complication of venous angiomas

Choreoballismus, developing subacutely in a 48-year-old man, is reported for the first time as a complication of a cerebral venous angioma, demonstrated by computed tomography scanning and angiography. There was no apparent hemorrhage or mass effect from the angioma, which was located in the right caudate nucleus. The movement disorder, which did not respond to haloperidol alone, disappeared after the addition of clonazepam. The necessity for dual therapy implies that there was a disorder of more than one neurotransmitter system in this patient. The clinical and pathological features of these unusual vascular malformations are reviewed.
Narrower Eigenbounds for Hadamard Products

Abstract The Schur theorem, established in 1911, defines the global bounds for all eigenvalues of Hadamard products of positive semidefinite matrices. We establish narrower, specific bounds for each eigenvalue.
Intranuclear inclusions in mammotrophs of the Mongolian gerbil: Effect of low doses of estradiol benzoate and a study of females before weaning

Abstract The effect of dose of estrogen on induction of intranuclear inclusions was studied in mammotrophs of the Mongolian gerbil. The number of inclusions per high power field increased significantly with 0.5 and 1.0 μg/day of estradiol benzoate but not with the 0.05 μg dose. A form of inclusion was seen in young female gerbils before weaning which suggests that inclusions arise from the cytoplasm. Intranuclear inclusions develop soon after weaning of gerbils (0.06 ± 0.01 vs . 0.19 ± 0.03 for young mature females).
Extremely high energy cosmic rays and neutrinos

Abstract The evidence for the existence of cosmic rays with energies in excess of 10 20 eV is now overwhelming. There is so far no indication of the GZK cutoff in the energy spectrum at 5 × 10 19 eV. This conclusion is not firm for lack of statistics. A cutoff would be expected if the sources of the cosmic rays were distributed uniformly through out the cosmos. The sources of cosmic rays with energy above the GZK cutoff must be at a distance ≤ 100 Mpc, and if they are protons they are very likely to point to these sources. There are no easy explanations how known astrophysical objects can accelerate protons (or atomic nuclei) to these energies. This difficulty has led to speculation that there may be exotic sources such as topological defects which produce these energetic cosmic rays directly along with a copious supply of neutrinos of similar energy. The fluxes of these cosmic rays is very low and large instruments are required to observe them even with modest statistics. One such instrument, the Pierre Auger Observatory, is described in some detail. It is designed for all-sky coverage and the construction of its southern site will begin in Argentina in 1999. This instrument has the capability to detect neutrinos with energy ≥ 10 18 eV and for some predictions neutrinos would actually be observed.
Extensive geographic and ontogenetic variation characterizes the trophic ecology of a temperate reef fish on southern California (USA) rocky reefs.

Interactions between predator and prey act to shape the structure of ecological commu- nities, and these interactions can differ across space. California sheephead Semicossyphus pulcher are common predators of benthic invertebrates in kelp beds and rocky reefs in southern California, USA. Through gut content and stable isotope (δ 13 C and δ 15 N) analyses, we investigated geographic and ontogenetic variation in trophic ecology across 9 populations located at island and mainland sites throughout southern California. We found extensive geographic variation in California sheephead diet composition over small spatial scales. Populations differed in the proportion of sessile filter/sus- pension feeders or mobile invertebrates in the diet. Spatial variation in diet was highly correlated with other life history and demographic traits (e.g. growth, survivorship, reproductive condition, and energy storage), in addition to proxies of prey availability from community surveys. Multivariate descriptions of the diet from gut contents roughly agreed with the spatial groupings of sites based on stable isotope analysis of both California sheephead and their prey. Ontogenetic changes in diet occurred consistently across populations, despite spatial differences in size structure. As California sheephead increase in size, diets shift from small filter feeders, like bivalves, to larger mobile inver- tebrates, such as sea urchins. Our results indicate that locations with large California sheephead pre- sent, such as many marine reserves, may experience increased predation pressure on sea urchins, which could ultimately affect kelp persistence.
The embeddability ordering of topological spaces

For K a set of topological spaces and X, Y ∈ K, the notation X ⊆h Y means that X embeds homeomorphically into Y ;a ndX ∼ Y means X ⊆h Y ⊆h X. With X := {Y ∈ K: X ∼ Y }, the equivalence relation ∼ on K induces a partial order h well-defined on K/∼ as follows: X h Y if X ⊆h Y . For posets (P ,P ) and (Q,Q), the notation (P ,P )� → (Q,Q) means: there is an injection h : P → Q such that p0 P p1 in P if and only if h(p0) Q h(p1) in Q .F orκ an infinite cardinal, a poset (Q,Q) is a κ-universal poset if every poset (P ,P ) with |P | κ satisfies (P ,P )� → (Q,Q). The authors prove two theorems which improve and extend results from the extensive relevant literature.
Interactions between dissolved natural organic matter and adsorbed DNA and their effect on natural transformation of Azotobacter vinelandii

To better understand gene transfer in the soil environment, the interactions between dissolved natural organic matter (NOM) and chromosomal or plasmid DNA adsorbed to silica surfaces were investigated. The rates of NOM adsorption onto silica surfaces coated with DNA were measured by quartz crystal microbalance (QCM) and showed a positive correlation with carboxylate group density for both soil and aquatic NOM in solutions containing either 1mM Ca(2+) or Mg(2+). Increasing total dissolved organic carbon (DOC) concentrations of the NOM solution also resulted in an increase in the adsorption rates, likely due to divalent cation complexation with NOM carboxylate groups and the phosphate backbones of the DNA. The results from Fourier transform infrared spectroscopy (FTIR) for dissolved DNA and DNA adsorbed on silica beads also suggest that adsorption may result from divalent cation complexation with the DNA's phosphate backbone. The interactions, between DNA and NOM, however, did not influence natural transformation of Azotobacter vinelandii by DNA. These results suggest that DNA adsorbed to NOM-coated silica or otherwise complexed with NOM remains available for natural transformation in the environment.
Influence of maturity and ripening on aroma volatiles and flavor in ‘Hass’ avocado

a b s t r a c t Changes in aroma volatiles were determined using solid phase microextraction (SPME) and gas chro- matography/mass spectrometry in ripe avocados (Persea americana Mill., cv. Hass) throughout an eight-month maturation period and related to the sensory properties of the fruit. As maturation pro- gressed sensory panelists found the likeability of the fruit to increase, coinciding with the fruit becoming creamier and less watery in texture, and the flavor richer and less grassy. During this maturation time the concentration of hexanal, (E)-2-hexenal and 2,4-hexadienal, three of the most abundant volatiles, greatly declined in amount. These volatiles all have a grass-like aroma, and it is likely that the loss in amount was responsible for the decline in grassy flavor during maturation. Acetaldehyde, methyl acetate, pen- tanal, and -myrcene were at higher concentrations in mature than non-mature fruit and may also have contributed to the overall flavor. Avocados of an intermediate maturity were ripened at 20 ◦C and fruit of different ripeness levels (firmnesses) measured for ethylene production, rate of respiration and aroma volatile content. A sharp increase in the rates of respiration and ethylene production marked a rapid increase in softening and the beginning of the climacteric. Twenty-five volatiles were identified in the ripening avocados of which three (pentanol, hexanol, and 2-nonenal) were not detectable in fully-ripe fruit. Of particular interest was an 85% decline in the amount of hexanal in a comparison of firm to fully ripe (4 N firmness) fruit. Aroma volatiles have in the past been little-studied in avocados but appear to have a role in determining the flavor of the fruit. Published by Elsevier B.V.
Developmental Expression of the Rat Somatostatin Gene

The developmental expression of the somatostatin (SRIF) gene was investigated in rat brain and stomach, two SRIF-rich tissues. The accumulation of raRNA encoding SRIF was determined in these organs during fetal and early (1–4 weeks) postnatal development using a sensitive radiodensitometric cDNA hybridization assay and a cloned preprosomatostatin cDNA. A single band of mRNA which hybridized specifically to the rat SRIF cDNA was detected in both tissues examined throughout ontogenesis, suggesting that the same SRIF gene is expressed in these tissues in the developing as well as in the adult rat. Whereas SRIF mRNA was undetectable in fetal stomach arid rose gradually only after birth, brain SRIF mRNA was already detectable by day 7 of embryonic life and reached concentrations corresponding to those in the adult brain by embryonic day 20. These marked differences may reflect basic differences in the developmental regulation of SRIF gene expression in neural vs. nonneural tissues or may be related to the onse...
Two-parameter robust repetitive control with application to a novel dual-stage actuator for noncircular Machining

This work presents a robust repetitive controller design for a novel dual-stage actuator system. The dual-stage actuator, which consists of an electrohydraulic actuator for 25-mm-gross motion and a piezoelectric actuator for 40-/spl mu/m fine motion, is designed for noncircular machining application. The controller is designed through a sequence of two single-input-single-output (SISO) designs by exploiting the triangular structure of the two by two actuator system dynamics. The tracking error from the first stage electrohydraulic actuator is used as reference for the second stage piezoelectric actuator. In this master-slave control arrangement, the overall sensitivity function is the product of two sensitivity functions from each actuator's servo loop. Thus, performance is improved at the frequencies where the sensitivity values are already well less than one. In the real-time control implementation, the effects of finite word length are analyzed and addressed via controller order reduction and realization. In an experiment of tracking an automotive cam profile at the rate of 10 cycles per second (600 rpm), the proposed dual-stage servo system generated tracking error of 4-/spl mu/m peak-to-valley and 0.80-/spl mu/m root-mean-square (RMS) value, showing a substantial improvement over the 16 micron peak-to-valley and 2.64-/spl mu/m RMS errors generated by the electrohydraulic servo system alone.
Headaches as a Presenting Symptom of Linear Morphea en Coup de Sabre

Linear morphea en coup de sabre (ECDS) is a form of localized scleroderma that predominantly affects the pediatric population, with a median age of 10 years at presentation. The existence of neurologic findings in association with ECDS has been well described in the literature. Here we describe 4 patients with ECDS who presented with headaches, which were typical migraines in 3 of the patients. The headaches preceded the onset of cutaneous findings by at least 6 months. Our patients’ cases emphasize both the importance of recognizing headaches as a harbinger of ECDS and the necessity of performing thorough cutaneous examination in patients with unexplained headaches or other neurologic disease.
Brute-force mining of high-confidence classification rules

This paper investigates a brute-force technique for mining classification rules from large data sets. We employ an association rule miner enhanced with new pruning strategies to control combinatorial explosion in the number of candidates counted with each database pass. The approach effectively and efficiently extracts high confidence classification rules that apply to most if not all of the data in several classification benchmarks.
A simple method to generate equal-sized homogenous strata or clusters for population-based sampling.

Purpose Statistical efficiency and cost efficiency can be achieved in population-based samples through stratification and/or clustering. Strata typically combine subgroups of the population that are similar with respect to an outcome. Clusters are often taken from preexisting units, but may be formed to minimize between-cluster variance, or to equalize exposure to a treatment or risk factor. Area probability sample design procedures for the National Children’s Study required contiguous strata and clusters that maximized within-stratum and within-cluster homogeneity while maintaining approximately equal size of the strata or clusters. However, there were few methods that allowed such strata or clusters to be constructed under these contiguity and equal size constraints. Methods A search algorithm generates equal-size cluster sets that approximately span the space of all possible clusters of equal size. An optimal cluster set is chosen based on analysis of variance and convexity criteria. Results The proposed algorithm is used to construct 10 strata based on demographics and air pollution measures in Kent County, MI, following census tract boundaries. A brief simulation study is also conducted. Conclusions The proposed algorithm is effective at uncovering underlying clusters from noisy data. It can be used in multi-stage sampling where equal-size strata or clusters are desired.
TU‐C‐J‐6B‐04: Deblurring of Breathing Motion Artifacts in Thoracic PET Images

Purpose: In FDG‐PET imaging, blurring due to breathing motion can significantly degrade the quality of the observed image, which can obscure the delineation of the tumor boundary. We demonstrate a new deblurring approach that combines patient‐specific motion estimates of tissue trajectories with imagedeconvolution techniques to partially remove breathing‐motion induced artifacts. Method and Materials: The human test data set consists of PET/CT co‐registered images of patients diagnosed with lungcancer. The motion measurements are obtained using a breathing model developed recently at our institution. The model linearly maps tidal volumes and airflow measu6red by spirometry into spatial trajectories. The parameters of the model are fitted using a template matching algorithm applied to CT data. The motion model is used to locally estimate the point spread function (PSF) due to breathing. The deconvolution process is carried by an expectation‐maximization (EM) iterative algorithm using the motion‐based PSF. Results: We evaluated the proposed motion‐based deblurring algorithm on idealized test data sets as well as two human PET images, one with a large and one with a small lungtumor. In this case, the estimated PSF would satisfy the shift‐invariance property. Rescaling was used to correct for limited image support in the case of small tumors, which could lead to undesirable ringing effects (Gibbs phenomena). The initial results showed improvement in the spatial resolution, especially in the cranio‐caudal direction. The EM algorithm converged within 20 iterations in both tumor cases. Generally, a compromise between entropy minimization and increase in MSE was used as a stopping criteria. Conclusion: We have implemented a method and algorithm for removing breathing motion from PET images. The initial results show that the method is promising for improving PET thoracic images.
Integration of STFT and Wigner analysis in a knowledge-based system for sound understanding

The authors describe and demonstrate how the combined use of Wigner and short-time Fourier transform (STFT) processing can be used to advantage in a sound understanding application. Specifically, the Wigner processing of a signal is used for alerting the signal understanding system to the possibility of inadequate time or frequency resolution in the STFT processing of the same signal. The signal understanding system may then reprocess the signal with an STFT with a different window length. The knowledge-based control required for carrying out such signal processing is available in a sound understanding system in the context of which this research was carried out. >
Glial fibrillary acidic protein expression in pleomorphic adenoma of salivary gland: an immunoelectron microscopic study.

Previous immunocytochemical studies of pleomorphic adenomas have demonstrated consistent labeling with glial fibrillary acidic protein (GFAP). Cross-reactivity with other intermediate filaments of similar structure and chemical composition has been suggested to account for this seemingly inappropriate pattern of immunoreactivity. To investigate further this phenomenon, we examined five pleomorphic adenomas by immunoelectron microscopy. Ultrastructural features were similar to those described by other investigators, with ductal epithelium being surrounded by myoepithelial cells and modified cells becoming detached to form the isolated stellate and spindle cells of the stroma. As part of this process, many neoplastic myoepithelial cells appeared to lose their specialized ultrastructural features, assuming a rather undifferentiated appearance. Single and double immunoelectron microscopic labeling showed vimentin filaments in all these neoplastic myoepithelial cells. In contrast, GFAP filaments were identifie...
Caring for patients with multiple chronic conditions: balancing evidenced-based and patient-centered care.

I do not recall any patient ever saying to me, “I am here today to discuss my multiple chronic conditions.” However, much of my time as a family doctor is spent doing exactly that. Patients with multiple chronic conditions generally come in because of their symptoms: “my knee pain is worse
Understanding the Ecological Validity of Neuropsychological Testing Using an Ethnographic Approach

Neurocognitive impairment is a defining and disabling feature of schizophrenia and other physical disorders. Most of our understanding about neurocognitive deficits comes from laboratory-based testing in research protocols. There has been little research using direct behavioral community observation over a prolonged period to understand the association of daily functioning with cognitive performance.The purpose of this study was to develop an observational method that could be replicated by researchers interested in viewing cognitive deficits in vivo, and then comparing this data to laboratory measures to affirm the ecological validity of those measures.The eight-step method explained here was developed from the targeted ethnographic study of 10 persons with schizophrenia. Obtaining real world context with this method will help to increase the generalizability of effective cognitive treatments, create improved interventions for this population, and bring into greater relief the coping and compensatory str...
T Cell—Tropic Simian Immunodeficiency Virus (SIV) and Simian-Human Immunodeficiency Viruses Are Readily Transmitted by Vaginal Inoculation of Rhesus Macaques, and Langerhans' Cells of the Female Genital Tract Are Infected with SIV

Human immunodeficiency virus (HIV) is transmitted primarily by sexual contact. An animal model, using the simian immunodeficiency virus (SIV)–rhesus macaque system, of HIV sexual transmission has been developed (reviewed in [1]). We have shown that cell-free SIVmac251 (reviewed in [1]) and some strains of SIV/HIV chimeric viruses (SHIV) [2] can cross the vaginal mucosa and initiate a systemic infection in rhesus macaques. Some studies of small numbers of individuals acutely infected with HIV through sexual contact suggest that the virus transmitted during such contact represents a variant present at low frequency in the transmitting partner’s virus population and that the transmitted virus is macrophage-tropic and nonsyncytium-inducing (NSI) [3]. The capacity of a virus to infect and productively replicate in discrete populations of cells is defined as tropism, and HIV and SIV variants have been classified on the basis of their in vitro ability to replicate in macrophages (macrophage-tropic), T cell lines (T cell–tropic), or both (dual-tropic). We hypothesized that the SIV or SHIV molecular clones that had a macrophage-tropic phenotype in vitro would be more likely to cross the vaginal mucosa and initiate a systemic infection than would be viral clones that were strictly T cell–tropic. We sought to test this hypothesis, using well-characterized clones of SIVmac, SHIV, and 2 uncloned viral stocks. Because a paper describing the details of this study has recently been published [4], only a summary and discussion of the work will be provided here. Studies characterizing immune cell populations in the genital tract of women and female rhesus macaques have demonstrated that antigen-presenting cells, macrophages, and CD1a+ Langerhans’ cells (LC) are the most abundant CD4+ cells in the cervicovaginal epithelium [5, 6]. We previously showed that SIV-infected cells are located in the vaginal epithelium and lamina propria of chronically infected rhesus macaques [7]; and a recent study demonstrated that 24 h after intravaginal SIV inoculation, cells in the lamina propria of the rhesus macaque vagina contain proviral DNA [8]. However, those studies did not definitively identify the type of cell that was infected. In this study, we sought to immunophenotype SIV-infected cells in the reproductive tract of chronically infected rhesus macaques. We now report that CD1a+/p55+ LC make up a large proportion of the SIV-infected cells in the lower genital tract of some chronically infected female rhesus macaques. Because a paper describing the details of these studies has been recently published [9], only a summary and discussion of the work will be provided here.
Balancing sensing and coverage in mobile sensor networks: A min-max approach

This paper presents a min-max algorithm for assigning mobile robots in a mobile wireless sensor network to different tasks that the network must perform. The algorithm minimizes the maximum penalty that is imposed when one of the tasks is not fully attended. The particular problem that we study is how to uniformly distribute autonomous mobile sensing robots inside a convex region while also quickly locating one or more sensory sources that might appear inside the region. The limited sensing capabilities of each robot suggest that several agents should collaborate to locate each source. The issue is then how to assign a sufficient number of robots to the sensing task and move them towards the source (even though some of them might initially not sense it), thereby diminishing the coverage of the region. We show that the proposed algorithm converges towards a stable equilibrium point. The algorithm is fully distributed and thus scalable. Simulation results that verify the theoretical claims are also presented.
Hydrogen Tunneling Links Protein Dynamics to Enzyme Catalysis

The relationship between protein dynamics and function is a subject of considerable contemporary interest. Although protein motions are frequently observed during ligand binding and release steps, the contribution of protein motions to the catalysis of bond making/breaking processes is more difficult to probe and verify. Here, we show how the quantum mechanical hydrogen tunneling associated with enzymatic C-H bond cleavage provides a unique window into the necessity of protein dynamics for achieving optimal catalysis. Experimental findings support a hierarchy of thermodynamically equilibrated motions that control the H-donor and -acceptor distance and active-site electrostatics, creating an ensemble of conformations suitable for H-tunneling. A possible extension of this view to methyl transfer and other catalyzed reactions is also presented. The impact of understanding these dynamics on the conceptual framework for enzyme activity, inhibitor/drug design, and biomimetic catalyst design is likely to be subs...
Sedge (Cyperaceae) achenes from the late Barstovian of Nebraska

JAMES, N. P., J. L. WRAY, AND R. N. GINSBURG. 1988. Calcification of encrusting aragonitic algae (Peyssonneliaceae): implications for the origin of late Paleozoic reefs and cements. Journal of Sedimentary Petrology, 58:291-303. JOHNSON, J. H. 1956. Archaeolithophyllum, a new genus of Paleozoic coralline algae. Journal of Paleontology, 30:53-55. MAMET, B. 1991. Carboniferous calcareous algae, p. 370-451. In R. Riding (ed.), Calcareous Algae and Stromatolites. Springer-Verlag, Berlin. MAZZULLO, S. J. 1981. Facies and burial diagenesis of a carbonate reservoir: Chapman Deep (Atoka Field), Delaware Basin, Texas. American Association of Petroleum Geologists Bulletin, 65:850-865. PEDONE, V. A., K. R. CERCONE, AND R. C. BURRUSS. 1990. Activators of photoluminescence in calcite: evidence from high-resolution, laserexcited luminescence spectrometry. Chemical Geology, 88:183-190. PRAY, L. C., AND J. L. WRAY. 1963. Porous algal facies (Pennsylvanian) Honaker Trail, San Juan Canyon, Utah, p. 204-234. In R. 0. Bass (ed.), Shelf carbonates of the Paradox Basin. Four Corners Geologic Society, Fourth Field Conference. RIDING, R. 1977. Problems of affinity in Paleozoic calcareous algae, p. 202-211. In E. Fliigel (ed.), Fossil Algae. Springer-Verlag, New York. AMES, N. P., J L. WRAY, AND R. N. GINSBURG. 1988. Calcification f encrusting aragonitic algae (Peyssonneliaceae): implications for the rigin of late Paleozoic reefs and ceme ts. Journal of Sedimentary TOOMEY, D. F., AND H. D. WINLAND. 1973. Rock and biotic facies associated with Middle Pennsylvanian (Desmoinesian) algal buildup, Nena Lucia field, Nolan County, Texas. American Association of Petroleum Geologists Bulletin, 57:1053-1074. WRAY, J. L. 1964. Archaeolithophyllum, an abundant calcareous alga in limestones of the Lansing Group (Pennsylvanian), southeastern Kansas. State Geological Survey of Kansas Bulletin, 170:1-13. 1968. Late Paleozoic phylloid algal limestones in the United States. XXIII International Geological Congress Proceedings, Prague, 8:113-119. . 1979. Paleoenvironmental reconstructions using benthic calcareous algae. Bulletin Center Research Exploration-Production ElfAquitaine, 3:873-879. ? 1985. Pennsylvanian algal carbonates and associated facies, central Colorado, p. 4.1-4.29. In Society of Economic Paleontologists and Mineralogists Midyear Meeting Guidebook, Field Trip No. 4, Golden, Colorado.
Robust estimation of encouragement design intervention effects transported across sites

We develop robust targeted maximum likelihood estimators (TMLE) for transporting intervention effects from one population to another. Specifically, we develop TMLE estimators for three transported estimands: intent-to-treat average treatment effect (ATE) and complier ATE, which are relevant for encouragement-design interventions and instrumental variable analyses, and the ATE of the exposure on the outcome, which is applicable to any randomized or observational study. We demonstrate finite sample performance of these TMLE estimators using simulation, including in the presence of practical violations of the positivity assumption. We then apply these methods to the Moving to Opportunity trial, a multi-site, encouragement-design intervention in which families in public housing were randomized to receive housing vouchers and logistical support to move to low-poverty neighborhoods. This application sheds light on whether effect differences across sites can be explained by differences in population composition.
Structure and electronic properties of grain boundaries in earth-abundant photovoltaic absorber Cu2ZnSnSe4.

We have studied the atomic and electronic structure of Cu2ZnSnSe4 and CuInSe2 grain boundaries using first-principles calculations. We find that the constituent atoms at the grain boundary in Cu2ZnSnSe4 create localized defect states that promote the recombination of photon-excited electron and hole carriers. In distinct contrast, significantly lower density of defect states is found at the grain boundaries in CuInSe2, which is consistent with the experimental observation that CuInSe2 solar cells exhibit high conversion efficiency without the need for deliberate passivation. Our investigations suggest that it is essential to effectively remove these defect states in order to improve the conversion efficiency of solar cells with Cu2ZnSnSe4 as photovoltaic absorber materials.
Defect Structure of Diamond Film at the Interface with Amorphous Carbon

Diamond films prepared by microwave plasma chemical vapor deposition, using a gas mixture of methane and hydrogen with ethanol, were formed on silicon substrates. Highresolution transmission electron microscopy was employed to characterize the microstructure at interface regions. It was found that the diamond crystals were grown on an amorphous carbon layer. Twins and stacking faults were observed at the regions interfaced with the amorphous carbon layer, suggesting that the defects may already exist in the nucleation stage and at the very first stage of growth. Also, some diamond nuclei embedded in the amorphous layer were observed.
Studies on the energy metabolism of human leukocytes. II. Mechanism of the Pasteur effect in human leukocytes.

Abstract 1. The control of glycolysis by respiration in normal human leukocytes was studied under conditions in which a Pasteur effect was present and under conditions in which this effect was lost. 2. There was a 20-50 per cent Pasteur effect in leukocytes isolated by dextran sedimentation of heparinized blood and suspended in isologous serum. Crossover point analysis of glycolytic intermediates indicate that phosphofructokinase becomes rate-limiting for aerobic glycolysis and that this enzyme is primarily responsible for the Pasteur effect. 3. Studies on the activity of PFK in leukocyte homogenates showed that this enzyme is competitively inhibited by ATP and reactivated by ADP and Pi. The concentrations of these compounds which significantly effect PFK activity in homogenates fall within the range found in intact cells. The differences in PFK activity in intact cells under anaerobic and aerobic conditions can therefore be attributed to allosteric effects caused by an increase in the concentration of ATP on transition to aerobic conditions, with concomitant decreases in the levels of ADP and Pi. 4. Leukocytes isolated by the same procedure but suspended in an artificial medium rather than serum did not show a Pasteur effect. There were no differences between the aerobic and anaerobic concentrations of ATP, ADP, and Pi, and there was no control point at PFK. It is suggested that a change in respiratory function is responsible for the altered control of glycolysis in leukocytes suspended in nonserum media.
The Effect of Unrestricted Immigration on Ethnic Voting and Racial Violence

Although some scholars of “realistic group conflict” argue that immigration usually causes ethnic conflict, Hopkins’ theory of “politicized places” suggests that the effect of immigrant flows depend on “salient national rhetoric.” To adjudicate between these two theories, this chapter analyzes three natural experiments: Mariel Cubans in Miami; Pieds-Noirs and Harkis “repatriates” in Marseille; and Eastern Europeans in Dublin. On the basis of interviews, archival materials, newspaper accounts, and King’s method of ecological inference, the study confirms Hopkins interpretation.
The paranoid personality. One of a series

Viewing the world about him as hostile and menacing, the paranoid individual uses characteristic traits to cope with that world and avoid a retreat into fantasy. On initial contact, the physician must be alert to the ways this patient reveals himself and subsequently must tactfully establish rapport to facilitate treatment.
Focused rapid echocardiographic evaluation versus vascular cather-based assessment of cardiac output and function in critically ill trauma patients.

BACKGROUND: Focused rapid echocardiographic evaluation (FREE) is a comprehensive transthoracic echocardiogram tailored for the intensive care unit. It assesses both the cardiac index (CI) and left ventricular ejection fraction (EF). FREE and vascular catheter-derived CI was compared, and the ability of CI to detect moderate to severe dysfunction (EF <40%) was determined. METHODS: FREE quality assurance database was reviewed to identify patients who had a hemodynamic catheter. RESULTS: Of 507 FREEs, 115 patients were identified, 25 pulmonary artery catheters (PACs) and 90 FloTrac Vigileo (FT/V) arterial catheters. There were 27 patients with an EF <40%. In 86%, the CI was determined by FREE, and it changed care in 59%. The CI correlation for FREE versus PAC was r = 0.88 and versus FT/V was r = 0.63 (p < 0.05). The PAC-FREE bias was -0.07 (95% confidence interval -0.89 to 0.74) and the FT/V-FREE bias was -0.13 (95% confidence interval -1.4 to 1.1). FREE-PAC categorized patients the same way 87% and FREE-FT/V 76%; in patients with EF <40%, this changed to 90% and 63%, respectively. Using a threshold value (CI ≤ 2.5), the PAC detected dysfunction in 62.5% and the F/VT in 6%, p < 0.05. CONCLUSIONS: There was excellent agreement between FREE and PAC but less with FT/V, especially in patients with and EF <40%. FREE can be used to validate catheter-derived data and provide important additional information. Further studies are needed to determine its impact on patient outcome. LEVEL OF EVIDENCE: III, diagnostic study.
Notizen: Physical Parameters and Possible Regulation of ζ-Aminolevulinic Acid Synthetase

Physical measurements were made on the zeta-aminolevulinic acid synthetase from Rhodopseudomonas spheroides. These include a Stokes radius of 3.8 nm, determined by gel filtration, and sedimentation coefficient of 5.46 S by sucrose density gradient centrifugation. From these measurements and the value of partial specific volume of 0.732 ml/g determined from the amino acid composition, the following physical constants were calculated: molecular weight, 88000; diffusion coefficient, 5.65 X 10(-7) cm2s-1; frictional ratio, 1.30; axial ratio, 5.0. The enzyme is inhibited by more than 50% by glyceraldehyde 3-phosphate (1mM), pyruvate (0.02 M), alpha-ketoglutarate (0.02 M), urea (0.8 M), CoCl2 (0.2 mM) and hemin (5 micrograms). The effect of these inhibitors on the possible regulation of this enzymic activity is discussed.
Getting more from investments in technology through technology asset planning

Most corporate systems are inadequate for the task of managing technology, and correcting this problem will be the most important senior management task of the 1990s. 'Technology asset management' is an emerging discipline, of which 'technology asset planning' is an important component. The author asserts that today, technology is too important to be managed solely by technologists. This paper outlines the factors which any company should consider in extending the strategic planning process and content to include technology asset planning. It shows how top management can come to understand the sources and magnitude of technology–related business risk associated with current business plans. This understanding can pave the way to judgements about prudent and acceptable risk levels, and lead to investigations into ways of modifying technology and business plans in order to reduce risk and increase return on investment.
Totality, Reason, Dialectics: The Importance of Hegel for Critical Theory from Lukács to Honneth

Critical theory has usually been regarded as a unique amalgamation of ideas drawn from Marx, Weber, and Freud, among other sources. What this view tends to minimize or overlook is the unique role of the critical theorists, beginning with Georg Lukacs (a critical theorist “before the fact”), in reviving, interpreting, and further developing a distinctively Hegelian approach to the problems of knowledge, culture, and politics. This chapter first demonstrates the role of critical theorists in reviving Hegelianism in the early twentieth century. Then, it outlines the role of Hegelian philosophy as the basis for concepts of totality in the thought of Georg Lukacs and Max Horkheimer, and of rationality in the thought of Herbert Marcuse and Theodor Adorno. The critique of, and then return to, Hegel in the work of Jurgen Habermas and Axel Honneth is also considered. The chapter concludes with an evaluation of three historical interpretations of the significance of the Hegelian element in critical theory, a consideration of the limits of Hegelianism for critical theory, and a suggestion of a fourth interpretation.
Cancer Epidemiology: A Survey of Modifiable Risk Factors for Prevention and Survivorship:

Approximately 40% of men and women in the United States will be diagnosed with cancer at some point in their lives. There have been dramatic developments in our understanding of cancer development and progression in recent decades, leading to improvements in screening and treatment, and in turn greater numbers of survivors living longer after diagnosis. Epidemiologic evidence of lifestyle-related factors and cancer risk and survival has been explored extensively in the published literature, with recommendations for cancer prevention and control and strategies for implementation evolving over time. This review summarizes the burden of cancer, general measurement issues in cancer epidemiology, and the current state of the science in specific lifestyle-related risk factors and cancer. It is estimated that one third to one half of cancers could be prevented by healthier lifestyle choices.
The natural history, treatment, and survival of 199 patients with sarcomatoid carcinoma of the prostate.

278Background: Sarcomatoid carcinoma of the prostate (SCP) is a rare and aggressive subtype of prostate cancer. Current data on clinical features, appropriate management and long-term outcomes of SCP are limited. Methods: A systematic review of literature was performed to identify published reports on SCP using keywords “sarcomatoid”, “prostate”, and “carcinosarcoma”. No randomized trials were identified. Four single-center case series and one registry-based study were included in final analysis. Results: In total, 199 patients were included in the review (54 from the SEER registry, 145 from the four case series). SCP occurs more frequently in the late sixth to seventh decade of life (age range: 28-91 years). Many patients with SCP (range, 48%-78%) have a history of prostate adenocarcinoma, with variable time to SPC onset (range, 0.5-20 years). Most tumors are high grade, with locally advanced or distant stage. Urinary obstruction was the most common symptom (50%-92%). Advanced stage was associated with p...
Effects of age-related shifts in cellular function and local microenvironment upon the innate immune response to implants

The host macrophage response is now well recognized as a predictor of the success or failure of biomaterial implants following placement. More specifically, shifts from an "M1" pro-inflammatory towards a more "M2-like" anti-inflammatory macrophage polarization profile have been shown to result in enhanced material integration and/or tissue regeneration downstream. As a result, a number of biomaterials-based approaches to controlling macrophage polarization have been developed. However, the ability to promote such activity is predicated upon an in-depth, context-dependent understanding of the host response to biomaterials. Recent work has shown the impacts of both tissue location and tissue status (i.e. underlying pathology) upon the host innate immune response to implants, representing a departure from a focus upon implant material composition and form. Thus, the ideas of "biocompatibility," the host macrophage reaction, and ideal material requirements and modification strategies may need to be revisited on a patient, tissue, and disease basis. Immunosenescence, dysregulation of macrophage function, and delayed resolution of immune responses in aged individuals have all been demonstrated, suggesting that the host response to biomaterials in aged individuals should differ from that in younger individuals. However, despite the increasing usage of implantable medical devices in aged patients, few studies examining the effects of aging upon the host response to biomaterials and the implications of this response for long-term integration and function have been performed. The objective of the present manuscript is to review the putative effects of aging upon the host response to implanted materials and to advance the hypothesis that age-related changes in the local microenvrionement, with emphasis on the extracellular matrix, play a previously unrecognized role in determining the host response to implants.