cssi/SciSciGPT-SciSciNet huggingface dataset:
Density Estimation with Replicate Heteroscedastic Measurements

We present a deconvolution estimator for the density function of a random variable from a set of independent replicate measurements. We assume that measurements are made with normally distributed errors having unknown and possibly heterogeneous variances. The estimator generalizes well-known deconvoluting kernel density estimators, with error variances estimated from the replicate observations. We derive expressions for the integrated mean squared error and examine its rate of convergence as n → ∞ and the number of replicates is fixed. We investigate the finite-sample performance of the estimator through a simulation study and an application to real data.
Water effects on atmospheric reactions

Water has a very significant impact on the processes that occur in the Earth's atmosphere. Water is one the most abundant resources in our atmosphere and, because of its ability to be both a hydrogen bond donor and acceptor, it can form very stable complexes. The formation of these complexes can dramatically affect the chemistry in the atmosphere, including heterogeneous removal and alteration of the photochemical properties of the atmospheric species, the formation of water droplets and aerosol particles, as well as the participation of these complexes in chemical reactions. The total effects of water regarding all of these processes are not entirely known and need to be studied further. This review provides a comprehensive look at both the experimental and theoretical investigations of water vapour effects on gas phase reactions, with an emphasis on those pertinent to the atmosphere. The results discussed here provide an understanding of the fundamental concepts that lead to potential water effects, imp...
Boson Resonance of Mass 980 MeV Decaying into π − η

An enhancement has been observed in the ${\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\eta}$ system at mass 980 \ifmmode\pm\else\textpm\fi{} 10 MeV with width 80 \ifmmode\pm\else\textpm\fi{} 30 MeV. This boson state, denoted by ${\ensuremath{\pi}}_{N}(980)$, yields a decay angular distribution having about 10% probability for isotropy. It is produced peripherally in the reaction ${K}^{\ensuremath{-}}+p\ensuremath{\rightarrow}{{Y}_{1}}^{*+}(1385)+{{\ensuremath{\pi}}_{N}}^{\ensuremath{-}}(980)$ at 5.5 GeV/c.
Risk factors for complications after performance of ERCP

Abstract Background: ERCP has become widely available for the diagnosis and treatment of benign and malignant pancreaticobiliary diseases. In this prospective study, the overall complication rate and risk factors for diagnostic and therapeutic ERCP were identified. Methods: Data were collected prospectively on patient characteristics and endoscopic techniques from 1223 ERCPs performed at a single referral center and entered into a database. Univariate and multivariate analyses were used to identify risk factors for ERCP-associated complications. Results: Of 1223 ERCPs performed, 554 (45.3%) were diagnostic and 667 (54.7%) therapeutic. The overall complication rate was 11.2%. Post-ERCP pancreatitis was the most common (7.2%) and in 93% of cases was self-limiting, requiring only conservative treatment. Bleeding occurred in 10 patients (0.8%) and was related to a therapeutic procedure in all cases. Nine patients had cholangitis develop, most cases being secondary to incomplete drainage. There was one perforation (0.08%). All other complications totaled 1.5%. Variables derived from cannulation technique associated with an increased risk for post-ERCP pancreatitis were precut access papillotomy (20%), multiple cannulation attempts (14.9%), sphincterotome use to achieve cannulation (13.1%), pancreatic duct manipulation (13%), multiple pancreatic injections (12.3%), guidewire use to achieve cannulation (10.2%), and the extent of pancreatic duct opacification (10%). Patient characteristics associated with an increased risk of pancreatitis were sphincter of Oddi dysfunction (21.7%) documented by manometry, previous ERCP-related pancreatitis (19%), and recurrent pancreatitis (16.2%). Pain during the procedure was an important indicator of an increased risk of post-ERCP pancreatitis (27%). Independent risk factors for post-ERCP pancreatitis were identified as a history of recurrent pancreatitis, previous ERCP-related pancreatitis, multiple cannulation attempts, pancreatic brush cytology, and pain during the procedure. Conclusions: The most frequent ERCP-related complication was pancreatitis, which was mild in the majority of patients. The frequency of post-ERCP pancreatitis was similar for both diagnostic and therapeutic procedures. Bleeding was rare and mostly associated with sphincterotomy. Other complications such as cholangitis and perforation were rare. Specific patient- and technique-related characteristics that can increase the risk of post-ERCP complications were identified. (Gastrointest Endosc 2002;56:652-6.)
Accrediting Neurology Fellowships Accelerates Subspecialization

In the 2011 American Academy of Neurology Residents Survey 86% of American neurology residents planned to complete a fellowship after their residency, up from estimates of 78% in 2008 and 74% in 1996 (1–3). There has been an increase in the types of subspecialty fellowship programs and, importantly, the available certifications. To understand the impact of this increasing accreditation one can compare two fields that overlap in the care of patients with acute ischemic or hemorrhagic stroke: Vascular Neurology, which is certified by the American Board of Psychiatry and Neurology (ABPN), and Neurocritical Care, which is certified by the United Council for Neurologic Subspecialties (UCNS). Within the United States and Canada, the ABPN and UCNS are the primary accrediting bodies of neurology fellowships. These organizations accredit fellowship programs that have applied and met predetermined standards. They also create their own exams and administer certification to qualified physicians who pass. The ABPN was founded in 1934 and the UCNS was founded in 2003 (Table ​(TableA1A1 in Appendix). The organizations have similarities, but one difference is the UCNS's interest in serving small subspecialties (4). This is significant for emerging subspecialties within neurology as the importance assigned to physician certifications by patients, employers, and other physicians will likely continue to grow. Changes in education and accreditation often occur after changes in practice have already occurred. Neurocritical Care has emerged as a new subspecialty over the past 30 years based on perceptions and evidence that neurologists with expertise in this area improved patient care (5). Fellowships in Neurocritical Care have existed for a number of years, but it is unclear how the creation of a UCNS Neurocritical Care certification in 2007 affected the neurology community's perception of Neurocritical Care as a subspecialty distinct from Vascular Neurology and General Neurology. Here we present data that the accreditation of Vascular Neurology and Neurocritical Care fellowships appears to have accelerated the divergence of these subspecialties.
Associations between eating frequency, energy intake, and body weight among 6-year-old children.

Eating frequency has been associated with reduced body weight in children in some, but not all studies. The purpose of this investigation, which is part of a longitudinal study (Stunkard et al., 1999), was to compare 6-year-old low-frequency (LF; n=21) and high-frequency (HF; n=21) eaters on: (a) the amount (g), energy (kcal), and energy density (ED; kcal/g) consumed per eating episode, (b) daily energy intake, and c) body composition. The daily number of eating episodes, defined as any eating/drinking occasion that was separated by at least 15 min, was generated from 3-day weighed food records. Children's anthropometric measures and body composition were assessed. Results showed that LF eaters, compared to HF eaters, consumed significantly more weight (244±13 vs. 175±9 g, P
Astrocytes and microglia respond to estrogen with increased apoE mRNA in vivo and in vitro.

Abstract This study examined the regulation of apolipoprotein E (apoE) by 17β-estradiol (E2) in brain glia, using rats with regular ovulatory cycles as anin vivomodel and cultured astrocytes and mixed glia asin vitromodels. Two brain regions were examined which had demonstrated transient synaptic remodeling during the estrous cycle. In the hippocampal CA1 region and the hypothalamic arcuate nucleus, apoE mRNA was elevated at proestrus when plasma E2 was high and synaptic density was increasing. Both astrocytes and microglia contributed to this increase in apoE mRNA.In vitro,E2 treatment had no effect on apoE mRNA levels in monotypic cultures of either astrocytes or microglia. In contrast, mixed glial cultures responded to E2 with increased apoE mRNA and protein, suggesting that heterotypic cellular interactions are important in the brain response to estrogens.In situhybridization in combination with cell-specific markers showed that E2 increased apoE mRNA levels in both astrocytes and microglia. These results, which are the first evidence of apoE mRNA localization to microgliain vivoand the control of apoE expression in brain cells by estrogens, are discussed in terms of the possible protective role of E2 in Alzheimer's disease and prior findings that emphasize the expression of apoE mRNA in astrocytes within the brain.
Dynamic Mechanical Properties of Some Polystyrene Composites

Dynamic shear modulus and damping have been determined on poly styrene filled with glass beads which have been given surface treatments, ground glass, ground rock salt, and foams made by extracting...
Antithrombotic effects of targeting αIIbβ3 signaling in platelets

αIIbβ3 interaction with fibrinogen promotes Src-dependent platelet spreading in vitro. To determine the consequences of this outside-in signaling pathway in vivo, a “β3(Δ760-762)” knockin mouse was generated that lacked the 3 C-terminal β3 residues (arginine-glycine-threonine [RGT]) necessary for αIIbβ3 interaction with c-Src, but retained β3 residues necessary for talin-dependent fibrinogen binding. β3(Δ760-762) mice were compared with wild-type β3+/+ littermates, β3+/− heterozygotes, and knockin mice where β3 RGT was replaced by β1 C-terminal cysteine-glycine-lysine (EGK) to potentially enable signaling by Src kinases other than c-Src. Whereas β3+/+, β3+/− and β3/β1(EGK) platelets spread and underwent tyrosine phosphorylation normally on fibrinogen, β3(Δ760-762) platelets spread poorly and exhibited reduced tyrosine phosphorylation of c-Src substrates, including β3 (Tyr747). Unlike control mice, β3(Δ760-762) mice were protected from carotid artery thrombosis after vessel injury with FeCl3. Some β3(Δ760-762) mice exhibited prolonged tail bleeding times; however, none demonstrated spontaneous bleeding, excess bleeding after surgery, fecal blood loss, or anemia. Fibrinogen binding to β3(Δ760-762) platelets was normal in response to saturating concentrations of protease-activated receptor 4 or glycoprotein VI agonists, but responses to adenosine diphosphate were impaired. Thus, deletion of β3 RGT disrupts c-Src–mediated αIIbβ3 signaling and confers protection from arterial thrombosis. Consequently, targeting αIIbβ3 signaling may represent a feasible antithrombotic strategy.
Comparison of dermal and epithelial approaches to laser tissue soldering for skin flap closure

Background and Objective Prior studies of laser tissue soldering (LTS) of epithelial skin have shown poor wound strength in the short-term; however, we hypothesize that greater tensile strength and healing properties will result from directing laser energy to the dermal aspect of the skin. The current study compares wound strength and histology in a rat skin flap model of epithelial and dermally applied LTS. Study Design/Materials and Methods: Skin flaps (2.5 × 4 cm) were raised and bisected on the dorsum of Sprague-Dawley rats. The center line of bisection was closed from a dermal approach by LTS (LTS-D, diode laser 15.9 W/cm2 + Columbia solder), the upper incision by epithelial LTS (LTS-E), and the lower incision by suturing (7-0 Vicryl). Wound skin strips (1–2 mm × 10 mm) were studied immediately (N = 14) and at 3 (N &equals 57), 7 (N = 31), and 10 (N = 28) days postoperatively and were subjected to tensiometric analysis. Histologic staining with hematoxylin and eosin and Mallory's trichrome methods were used to define wound architecture. Results No wound dehiscences were noted in any group. Greater immediate tensile strength was noted in wounds closed by LTS-D (521 ± 61 g/cm2) versus LTS-E (342 ± 65 g/cm2); however, this difference was not statistically significant (P = .08). By 3 days, both LTS-D (476 ± 55 g/cm2) and LTS-E (205 ± 37 g/cm2) maintained their initial strength; however, LTS-D and sutured (436 ± 49 g/cm2) wounds were stronger (P < .05) than LTS-E. At 7 and 10 days, LTS-D (2,433 ± 346 g/cm2 and 3,100 ± 390 g/cm2) showed superior tensile strength (P < .05) compared to both LTS-E (1,542 ± 128 g/cm2 and 2,081 ± 219 g/cm2) and suturing (1,342 ± 119 g/cm2 and 1,661 ± 115 g/cm2). Histologic analysis of LTS-D wounds at 3 days showed full-thickness tissue apposition, complete epithelialization, and minimal inflammation or thermal injury. At 7 days, solder was present in the wounds. In contrast, LTS-E wounds at 3 days displayed lack of epithelialization secondary to thermal injury and partial-thickness tissue apposition. However by 7 days, epithelialization was complete with moderate scarring, and no solder was seen. Sutured samples appeared similar to LTS-D, except for poorer tissue apposition at the hypodermis. Conclusion Our results show that skin flap wound healing after dermal LTS is superior to epithelial LTS and emphasizes the importance of site specificity in the utilization of this operative technique in reconstructive surgery. Lasers Surg. Med. 22:268–274, 1998. © 1998 Wiley-Liss, Inc.
Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system

Abstract Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or mutagens. Groundwater contamination by these toxic compounds may pose an environmental health hazard in nearby public water-supply wells. Fluid samples from this aquifer developed two phases upon settling: an upper aqueous phase, and a lower oily-tar phase. After separating the phases, polycyclic aromatic compounds in each phase were isolated using complexation with N-methyl-2-pyrrolidone and identified by fused-silica capillary gas chromatography/mass spectrometry. Thirty-one of the polycyclic aromatic compounds were chosen for further study from four different classes: 12 polycyclic aromatic hydrocarbons, 10 nitrogen heterocycles, 5 sulfur heterocycles, and 4 oxygen heterocycles. Within each compound class, the tar/water partition coefficients of these compounds were reasonably comparable with the respective n-octanol/water partition coefficient.
Emerging therapies: clopidogrel and aspirin.

To the Editor: We read with interest the commentaries regarding the recently published Management of Atherothrombosis with Clopidogrel in High-Risk Patients (MATCH) trial1 and wish to contribute some additional perspectives. Patient baseline characteristics have been cited as reasons for the neutral results and detrimental outcomes observed.1 The large number of patients with small-vessel qualifying events is one reason cited for treatment failure, and Dr Caplan notes that there were “too few patients with documented large-artery disease in MATCH.” On the contrary, the prevalence of lacunar infarctions among participants in MATCH was similar to or less than that of other recent large randomized cerebrovascular trials …
Effects of short term triiodothyronine administration to broiler chickens fed methimazole.

The purposes of these experiments were to determine possible relationships among certain indices of lipid metabolism and specific gene expression in chickens ( Gallus gallus ) fed methimazole (MMI) and the subsequent effects of providing supplemental T 3 to relieve the effects of MMI. Male, broiler chickens growing from 14 to 28 days of age were fed diets containing 18% crude protein and either 0 or 1 g MMI/kg of diet. At 28 days, birds received 18% crude protein diets containing either 0 or 1 mg triiodothyronine (T 3 )/kg. Birds were sampled at 0, 1, 2 & 4 days post relief from MMI or at 0, 3, 6, 9, 24 & 48 h. Measurements taken in the first experiment included in vitro lipogenesis (IVL), malic enzyme (ME), isocitrate dehydrogenase (ICD-NADP), aspartate aminotransferase (AST) enzyme activities and the expression of the genes for ME, fatty acid synthase (FAS) and acetyl coenzyme carboxylase (ACC), ICD and AST. The same enzyme activities and gene expressions were assayed over the intervals mentioned above. In vitro lipogenesis was eliminated due to constraints imposed by sampling times. Gene expression was estimated with real time RT-PCR assays. Dietary MMI decreased IVL and ME at 28 days of age. T 3 supplementation for 1 day restored both IVL and ME. Continuing T 3 replenishment decreased IVL without affecting ME activity. Although MMI decreased ME gene expression, there was only a transitory relationship between enzyme activity and gene expression when apparent thyroid function was restored with exogenous T 3 . Metabolic changes in response to feeding T 3 occurred within a short period, suggesting that changes in intermediary metabolism preceded morphological changes. Furthermore, the thyroid state of the animal will determine responses to exogenous T 3 .
Daughter succession: a predominance of human issues

Purpose – The research asked: How do daughters take the lead in their family businesses? What are the relevant issues that characterize the succession process for daughters, what are the attributes of daughter successors, and what, if any, features distinguish their leadership style?Design/methodology/approach – Qualitative research comprised reflective interviews with 14 daughter successors. Thematic data analysis was used to analyze data, build models and link to previous research.Findings – The shifting landscape of women's roles in family businesses is evidenced through the experiences of daughters who have taken over the top leadership positions in their family firms. Skill and commitment override gender in successor selection. The women were intrinsically motivated to take over their family businesses and owned significant shares in their firms. The findings confirm the centrality of the successor‐incumbent relationship and reveal mentoring, frequently by the incumbent, as the principal vehicle for ...
Surface plasmon dispersion in liquid mercury

The electronic properties of the surface of liquid mercury have been studied from 1 to 6.5 eV via the interaction of the electromagnetic field with the surface plasmons. Our results strongly suggest the existence of an atomic configuration encompassing the outermost two or three atomic layers which is more ordered than the interior. On the basis of model calculations we also postulate a weak, but significant, interaction between the bulk and surface plasmons. The model which we propose here accounts well for our surface-plasmon data and for available ellipsometric and reflectance measurements.
Treatment of intravenously implanted Lewis lung carcinoma with liposome-encapsulated cytosine arabinoside and non-specific immunotherapy.

Liposomes have been used as biological carriers of antitumor drugs, and their potential use has been tested using various mouse tumors. In this study, we describe a potential role of liposome-encapsulated 1-beta-D-arabinofuranosylcytosine (Ara-C) with a mouse solid lung tumor model. Non-encapsulated Ara-C at 25 mg/kg dose by the intraperitoneal (i.p.) route on days 1, 4 and 7 had no improving effect on the average survival time of tumor-bearing mice compared to untreated control mice. However, the same dose of Ara-C encapsulated in multilamellar liposomes (MLV) improved the average survival of tumor-bearing mice by 60 to 80%. Ara-C was encapsulated more efficiently when DSPC or DPPC MLV were prepared at temperatures below their respective transition temperatures. DSPC and DPPC MLV prepared at 25 degrees C and DPPC MLV prepared at 50 degrees C were equally effective for in vivo therapy, while DSPC MLV prepared at 60 degrees C were not as effective. Non-specific immunotherapy using BCG (Bacillus Calmette-Guerin, Mycobacterium tuberculosis) and CP Corynebacterium parvum) was effective, particularly when injected by the intravenous (i.v.) route, in prolonging the average survival of tumor-bearing mice. A combination of either i.v. BCG or i.p. CP with liposome therapy gave no further improvement in the average survival of tumor-bearing mice. However, a combination of either i.p. BCG or i.v. CP with liposome therapy was somewhat more effective than either liposome therapy or immunotherapy alone.
Plasma zinc concentrations during the first 2 years after diagnosis of insulin-dependent diabetes mellitus: a prospective study

Melchior T, Wiese Simonsen K, Johannessen AC, Binder C (Steno Memorial Hospital, Gentofte and Department of Chemistry AD, Royal Danish School of Pharmacy. Copenhagen. Denmark). Plasma zinc concentrations during the first 2 years after diagnosis of insulin-dependent diabetes mellitus: a prospective study. Studies of zinc status in insulin-dependent diabetes mellitus (IDDM) have shown contradictory results. Zinc is essential for many enzymes involved in the human metabolism and may play a role in the biosynthesis and storage of insulin in the B-cell. We therefore prospectively followed 26 patients (14 males and 12 females) with newly diagnosed IDDM in order to determine the plasma zinc variation at the time of diagnosis and after 1, 3, 6, 12 and 24 months. Seventy-two healthy persons (36 males and 36 females) served as controls. Only minor differences in plasma zinc were demonstrated during the first 2 years of IDDM. A sex difference was found in healthy controls but only after 24 months in the diabetics. Quantitative changes of the B-cell function, development of insulin antibodies, age. body weight and serum albumin did not correlate with the course of plasma zinc.
Dominance at the Tox1 locus controlling T-toxin production by Cochliobolus heterostrophus

Abstract Heterokaryons of Cochliobolus heterostrophus were constructed which contained approximately equal numbers of nuclei bearing either the tox1+ allele for presence of T-toxin or the tox1− allele for absence of T-toxin in culture filtrates. The heterokaryons were grown in a liquid medium known to support production of T-toxin; the resulting culture filtrates were assayed for T-toxin activity using 2 different bioassays: seedling root growth and dark CO2 fixation. Both assay procedures detected the presence of T-toxin in culture filtrates of tox1 + tox1 − heterokaryons; levels of activity were slightly less than those found in filtrates from tox1 + tox1 + heterokaryons. Since these heterokaryons are known to function as diploids, the simplest interpretation of the results is that the tox1+ allele, which determines high virulence as well as T-toxin production, is either dominant or semidominant.
Amplitude-reduction and acrophase-advance of circadian mitotic rhythm in corneal epithelium of mice with bilaterally lesioned suprachiasmatic nuclei.

Lesions of the suprachiasmatic nuclei (SCN) have been reported to disrupt or abolish circadian rhythms of motor activity and body temperature as well as of several neuroendocrine functions. This study was undertaken to determine any effect the SCN may have on the prominent circadian rhythm characteristic of the mitotic index of the corneal epithelium. Singly caged adult mice of both sexes were fed ad libitum and standardized to 12 hours of light alternating with 12 hours of darkness. Animals were divided into experimental and control groups. Later they were killed in subgroups at the time intervals of 0800, 1200, 1000, 0000, 0400 hour. Mitotic counts were determined on both right and left corneas of all mice. The data were plotted separately for both groups and reflect colony variation. We conclude that major lesioning of the SCN or its efferent projections disturbed but did not abolish the rhythm. In animals with unilateral lesions of the SCN, the mitotic index was consistently lower in the ipsilateral cornea. The mitotic index for animals with lesions which missed the SCN or its efferent projections did not differ from controls. The nuclei appear to function as pace-resetters and amplifiers of the rhythm studied.
Hydroxyurea for the treatment of sickle cell anemia

An 18-year-old woman with sickle cell anemia presents with recurrent painful crises, and treatment with hydroxyurea is recommended. Hydroxyurea causes a shift toward the production of red cells containing fetal hemoglobin. A possible increase in the risk of acute leukemia due to hydroxyurea therapy remains the subject of debate.
Evaluation of an alternative posaconazole prophylaxis regimen in haematological malignancy patients receiving concomitant stress ulcer prophylaxis

Posaconazole (PCZ) is approved for fungal prophylaxis in high-risk neutropenic patients. Unfortunately, PCZ oral absorption is affected by nutritional intake and drug interactions with proton pump inhibitors (PPIs) and possibly histamine-2 antagonists (H2As). Cancer patients frequently receive stress ulcer prophylaxis (SUP) with PPIs or H2As. Recommended PCZ steady-state concentrations (C(ss)) are difficult to achieve using the traditional dosing regimen of 200 mg thrice daily. Given the paucity of guidance on PCZ dosing in patients receiving SUP, this study evaluated attainment of targeted PCZ C(ss) (0.5 μg/mL and 0.7 μg/mL) with two different PCZ dosing regimens when SUP was given. Twenty patients received the traditional dosing and 34 patients received 400 mg twice daily. Median PCZ C(ss) levels were 0.37 μg/mL and 0.32 μg/mL with the traditional and 400 mg twice-daily regimens, respectively (P=0.809). When stratified by type of SUP, H2A patients had a median PCZ C(ss) of 0.39 μg/mL, whereas PPI patients had a median PCZ C(ss) of 0.32 μg/mL. Despite having more patients with PCZ C(ss) >0.5 μg/mL in the H2A group, a statistical significance was not found (P=0.368). Multiple logistic regression did show that increasing age [odds ratio (OR)=1.08, 95% confidence interval (CI) 1.03-1.19] and use of H2As over PPIs (OR=6.8, 95% CI 1.22-55.16] was associated with PCZ target attainment. These results suggest that PCZ target attainment is similar with either PCZ regimen but that there may be less of an interaction with H2As compared with PPIs.
Breast Care in Pregnancy

The author is an Assistant Professor of the Maternal & Child Health Care Nursing Associate Degree Program at Indiana University‐Purdue University in Indianapolis. She has designed her program for breast care to ensure satisfactory breastfeeding for the new mother. However, the nonbreastfeeding mother will also benefit.
Further Studies on Serum Protein Formation by Chimeras I. Effect of Cytotoxic Agents on Serum Protein Formation

SummaryRat-into-mouse chimeras were produced by injection of rat bone marrow into irradiated or CY treated animals. Both groups of animals were given interval injections of CY during the first 2 weeks after the initial procedure. The degree of chimerism in the CY induced chimeras was limited and confined only to hematopoietic tissues. Donor type serum proteins were never detected in cultures of spleens or peritoneal macrophages. In the X-irradiated group, the only serum protein of donor origin produced by the chimeric tissues in vitro was Tr, which correlated with its presence in the sera of these animals.
Kinetic aspects of analytical chemistry: progress and emerging trends.

There is growing awareness of the importance of kinetics in analytical chemistry today. This new appreciation stems from the increasing number of applications dealing with bioanalytical systems as well as demonstrations that using time as a variable in analytical measurements can yield results with improved sensitivity and selectivity. This article describes some of the progress that has been made in recent years in measuring and exploiting kinetics in analytical chemistry. A survey of the literature comparing recent papers with those from the 1995– 1997 time period shows that dynamic methods are on the increase in the field. From this survey, the types of kinetic methods that are on the increase and those that are in decline are identified. Finally, this paper focuses on two areas in which future growth is expected to occur, microfluidics-based kinetic measurements and nanobiosensors.
Microparticle dispensers for the controlled release of insect pheromones

The potential utility of micrometer-sized particles as controlled-release devices for the volatilization of insect pheromones for mating disruption applications is evaluated in this study for two pheromone/model compound systems (codlemone/1-dodecanol and disparlure/1,2-epoxyoctadecane). To expedite the measurement of release rates from these particle devices, two techniques based on thermogravimetric analysis (TGA) have been exploited: isothermal TGA (I-TGA) at elevated temperatures (40−80 °C) with N2 convection and volatilization temperature (VT) by dynamic TGA. A correlation between these two methods has been established. Samples that exhibit a higher VT provide a lower release rate from a particle substrate. Using these techniques, it has been demonstrated that chemical interactions between adsorbed liquids and particle surfaces may play a small role in defining release characteristics under conditions of low surface area, whereas parameters associated with total surface area and micropore structure ...
A Monte Carlo method for Poisson's equation

Abstract This investigation presents an analysis of a Monte Carlo method for estimating local solutions to the Dirichlet problem for Poisson's equation. The probabilistic algorithm consists of a modified “walk on spheres” that includes the effects from internal sources as part of the random process. A new derivation of the asymptotic expressions for the rate of convergence and average runtime of the algorithm is presented. These estimates are used to compare the Monte Carlo method with discrete difference schemes. Numerical experiments involving some two-dimensional problems confirm the efficiency of the probabilistic scheme.
Self-assembly of apoferritin molecules into crystals: thermodynamics and kinetics of molecular level processes

Abstract Aside from the biological, biomedical and materials importance of ferritin and apoferritin, the self-assembly of these molecules into crystals is of interest because it is a suitable model for protein crystallization and aggregation that impact many fundamental and applied fields. We use the atomic force microscope in-situ, during the crystallization of apoferritin to visualize and quantify at the molecular level the processes responsible for crystal growth. We image the configuration of the incorporation sites, “kinks”, on the surface of a growing crystal. We show that the kinks are due to thermal fluctuations of the molecules at the crystal-solution interface. This allows evaluation of the free energy of the intermolecular bond φ = 3.0 kBT = 7.3 kJ/mol. The crystallization free energy, extracted from the protein solubility, is − 42 kJ/mol. Thermodynamics analyses based on these two values suggest that the main component in the crystallization driving force is the entropy gain of the waters bound to the protein molecules in solution and released upon crystallization. Furthermore, we determine the characteristic frequency of attachment of individual molecules into the kinks at one set of conditions. We show that the macroscopic step growth velocity, scaled by the molecular size, equals the product of independently determined kink density and attachment frequency, i.e., these are the molecular-level parameters for crystallization. Finally, we show that although new crystal layers are generated by intrinsically stochastic surface nucleation, for crystals > 200 μm layer generation predominantly occurs at the crystal edges. Numerical simulations of the concentration fields in the solution allow us to assign this localization to higher interfacial concentration at the edges. As the steps propagate to cover the crystal face, step density waves, or bunches, develop and may lead to non-uniformity and lower quality and utility of the growing crystal.
Promotion’s Limited Impact in the 2000 Sydney Olympics:

Lower-than-expected ratings made the 2000 Sydney Olympics an unusual promotional platform and led the National Broadcasting Company (NBC) to alter its on-air plans for marketing its fall 2000 prime-time schedule while the event was proceeding. This study assessed the impact of the prime-time promos carried in the 2000 Games on post-Olympics program ratings. A comparison of before-and-after difference scores for each promoted program showed that only one-quarter of its promoted programs rose in the ratings after the event, half stayed flat, and one-third went down, despite NBC’s having the top-rated shows at the time. Ten factors were identified that potentially affected the promos’ collective impact. From a theoretical perspective, the findings suggested two new variables that might be incorporated in salience theory and from a practical perspective, suggested that NBC’s unusual promotional practices led to too little exposure time and repetition for effective promotion.
Antipurinergic Therapy Corrects the Autism-Like Features in the Poly(IC) Mouse Model

Background Autism spectrum disorders (ASDs) are caused by both genetic and environmental factors. Mitochondria act to connect genes and environment by regulating gene-encoded metabolic networks according to changes in the chemistry of the cell and its environment. Mitochondrial ATP and other metabolites are mitokines—signaling molecules made in mitochondria—that undergo regulated release from cells to communicate cellular health and danger to neighboring cells via purinergic signaling. The role of purinergic signaling has not yet been explored in autism spectrum disorders.
Transcriptional repression of the human collagenase-1 (MMP-1) gene in MDA231 breast cancer cells by all- trans -retinoic acid requires distal regions of the promoter

In the present study, we investigated the mechanisms controlling constitutive transcription of collagenase-1 and its repression by all-trans-retinoic acid (RA) in the highly invasive metastatic and oestrogen-receptor-negative breast cancer cell line MDA231. A combination of in vivo and in vitro experiments that include DNAase I hypersensitivity assays, transient transfection of collagenase-1 promoter constructs, and electrophoretic mobility shift assays implicate several PEA3 sites, binding sites for Ets-related transcription factors, in the constitutive expression of the human collagenase-1 promoter. Transient transfection of promoter constructs linked to the luciferase reporter, along with gel retardation assays, revealed that repression of collagenase-1 transcription by RA is not dependent on the proximal AP-1 site, but, rather, requires sequences located in distal regions of the promoter. Transcriptional analyses and electrophoretic mobility shift assays suggest that the PEA3 site located at –3108 bp facilitates, at least in part, the transcriptional repression of the human collagenase-1 gene in MDA231 cells. We conclude that collagenase-1 repression in MDA231 cells occurs by a novel regulatory pathway that does not depend on the proximal AP-1 site at –73 bp, but does depend on distal regions in the collagenase-1 promoter. © 1999 Cancer Research Campaign
The anemia of chronic disease: Spectrum of associated diseases in a series of unselected hospitalized patients

Purpose Previous studies of the anemia of chronic disease (ACD) have generally begun with patients afflicted with one of the classical underlying diseases such as rheumatoid arthritis. The clinical spectrum of ACD has not been thoroughly examined. We hypothesized that many patients have an anemia with the characteristics of ACD but do not have one of the infectious, inflammatory, or neoplastic disorders usually associated with ACD. We therefore evaluated a series of consecutive, unselected, anemic patients admitted to a county hospital. Patients and methods All patients admitted to the medicine ward service of a county hospital were screened for anemia (hematocrit less than 40% in men, less than 37% in women). Additional laboratory data were collected on all anemic patients, except those with active gastrointestinal bleeding, hemolytic disease, or leukemia or multiple myeloma. The patiente were divided into three groups on the basis of serum values indicating iron distribution: iron deficiency (serum ferritin less than 10 ng/mL), ACD (serum iron less than 60 μg/ dL and serum ferritin more than 50 ng/mL), and all others (non-ACD). The hospital records of the patients in the hitter two groups were reviewed and their diagnoses recorded. Results Seven patients with iron deficiency were not considered further. Ninety patiente with ACD were compared with 75 patiente with non-ACD. The anemia in ACD patiente was more severe than most authors describe. The mean hematocrit was 31%, and 20% of patiente had hematocrite below 25%. The anemia was usually normocytic (mean red cell volume [MCV] 86 fL), but 21% had an MCV less than 80 fL. The level of saturation of serum iron-binding capacity was quite low in ACD (mean 15%) and was normal in non-ACD (mean 31%). Renal insufficiency was common in both groups; serum creatinine values were more than 2 mg/dL in 31% of patiente with ACD and 20% of non-ACD patiente. Sixty percent of patiente with ACD had a principal diagnosis that fell into the infectious, inflammatory, and neoplastic categories commonly associated with ACD. Renal insufficiency was the major diagnosis in 16%, and the principal diagnosis in 24% was a disease not commonly considered to be associated with ACD. In non-ACD patiente, the principal diagnosis was an infectious, inflammatory, or neoplastic disease in 55%, renal insufficiency in 9%, and another disease in 36%. Conclusions When ACD was defined by the abnormalities of iron distribution, which are its most consistent and widely accepted characteristics, the spectrum of associated diseases was much broader than the traditional categories of infectious, inflammatory, and neoplastic disorders, and the overlap with non-ACD was large. Until the etiologic and pathogenetic mechanisms of ACD are better understood, a flexible and inclusive view of this disorder seems appropriate.
The smell of nature: Olfaction, knowledge and the environment

Abstract Olfaction offers unique entry into the non‐human world, but Western culture constrains such opportunities because of the dominance of the visual mode of perception. We begin by briefly reviewing philosophical arguments against olfaction as a reliable cognitive input. We then build a biological case for the similarity of non‐human and human olfaction. Subsequently, we argue that some contemporary societies still make use of olfaction for organizing themselves in space and time. We end by suggesting that olfaction offers promise for advancing inquiry into the human‐nature relationship that is so important to many environmental philosophers, scientists and activists.
Comparison of Recent and Ancient Coarse-Grained Point Bars: ABSTRACT

Sequences of sedimentary structures in modern point-bar deposits of the Amite River in east Baton Rouge Parish, Louisiana, are analogous to features observed End_Page 731------------------------------ in Eocene Simsboro deposits in Milam County, Texas. Annual rainfall of approximately 60 in., channel pattern slightly to highly meandering, average stream gradient of about 5 ft/mi, and bank stabilization by dense vegetation are major parameters controlling Amite deposition of coarse sand and pebble-gravel sediment. Stratification types are related directly to specific depositional features, and include (from thalweg to overbank): thalweg (large-scale cross-stratification), lower point bar (trough cross-stratification, avalanche beds), chute bar (parallel laminae, avalanche beds, trough fill), chute fill (parallel inclined laminae, climbing ripples), and overbank (parallel inclined laminae, mud drape, avalanche beds). Fundamental differences between point bars of streams transporting coarse-grained bed load and streams having fine-grained bed load are: muddy floodplain deposits are associated only with fine-grained bed-load streams; upper point-bar sediments with ripple cross-stratification and parallel inclined laminae occur only in fine-grained fluvial deposits; chute-front avalanche beds are common in coarse-grained fluvial deposits but are not found in fine-grained fluvial deposits. Coarse-grained fluvial deposits do not show the upward decrease in grain size that is reported to characterize fluvial sediment. The Simsboro consists mainly of thalweg, lower point-bar, and chute-bar deposits; chute-fill and overbank deposits are preserved only in the last depositional sequence. End_of_Article - Last_Page 732------------
Giemsa banding specificity.

THE wide variety of techniques capable of producing banding with Giemsa stain has created interest in the possible mechanisms involved1–3. The problem has been to explain the apparent base specificity of Giemsa bands1,4, as, without the various banding treatments, Giemsa produces uniformly stained chromosomes except for the primary and secondary constrictions. This indicates that Giemsa staining is not base specific, but that various physiochemical treatments can produce condensation and staining changes so that “interbands” (pale staining regions) develop. It has been demonstrated that such banding is not simply the result of denaturation and re-naturation of repetitive DNA base sequences, but rather results from modifications of DNA-protein or protein-protein association1–3 so that a staining reaction which probably involves both thiazine intercalation on DNA and eosin interaction with protein is effected5. Thus, it is DNA-protein associations which determine Giemsa staining and disruption of such associations, either through protein loss, physiochemical modifications, or conformational changes, results in decreased staining of interbands. This implies base specific protein associations and requires an examination of the nature of these proteins, to find whether they are acidic and/or basic, as a requisite for evaluating their genetic function.
Morphine tolerance and transcription factor expression in mouse spinal cord tissue

Little is known about changes in gene expression responsible for the acquisition and maintenance of tolerance to the analgesic effects of opioids. In these studies we examine changes in the expression of several transcription factors in the spinal cords of morphine tolerant C57BL/6 mice. Western blots demonstrate a 1.9-fold increase in cyclic AMP response element binding protein (CREB) and a 2.4-fold increase phospho-CREB immunoreactivities in spinal cord homogenates from morphine tolerant animals. Likewise, Fos B and ΔFos B immunoreactivities were increased 2.2 and 2.3-fold, respectively. The expression of c-Fos remained unchanged. Immunohistological analysis showed the increase of phospho-CREB and Fos B/ΔFos B to be primarily in the dorsal horn region of the spinal cord. We conclude that chronic exposure to opioids causes changes in gene expression in sensory processing areas of the spinal cord.
Multimodal energy expenditure calculation for pervasive health: A data fusion model using wearable sensors

Accurate estimation of energy expenditure during exercise is important for professional athletes and casual users alike, for designing training programs and meeting their fitness goals. However, producing an accurate estimate in a mobile, wearable health-monitoring system is challenging because most calculations require knowledge of the subject's movement speed. Though determining precise movement speed is trivial on a treadmill, inaccuracies of the sensors in a mobile system have a negative impact on the accuracy of the final energy expenditure estimate. In this paper, we propose a novel method to calculate energy expenditure using sensor fusion, in which data from multiple sensors is combined to formulate the result, based on a linear-regression model. We combine data from our wearable system with embedded pulse sensor and pedometer to produce an estimate that is far more accurate than possible with the pedometer alone, reducing our mean-absolute error by 64.3%. These results indicate that it is possible to obtain an accurate energy expenditure estimate in a multi-sensor system, even with affordable, low-cost, and pervasive components that may not be accurate individually.
Krylov implicit integration factor WENO methods for semilinear and fully nonlinear advection-diffusion-reaction equations

Implicit integration factor (IIF) methods are originally a class of efficient ''exactly linear part'' time discretization methods for solving time-dependent partial differential equations (PDEs) with linear high order terms and stiff lower order nonlinear terms. For complex systems (e.g. advection-diffusion-reaction (ADR) systems), the highest order derivative term can be nonlinear, and nonlinear nonstiff terms and nonlinear stiff terms are often mixed together. High order weighted essentially non-oscillatory (WENO) methods are often used to discretize the hyperbolic part in ADR systems. There are two open problems on IIF methods for solving ADR systems: (1) how to obtain higher than the second order global time discretization accuracy; (2) how to design IIF methods for solving fully nonlinear PDEs, i.e., the highest order terms are nonlinear. In this paper, we solve these two problems by developing new Krylov IIF-WENO methods to deal with both semilinear and fully nonlinear advection-diffusion-reaction equations. The methods can be designed for arbitrary order of accuracy. The stiffness of the system is resolved well and the methods are stable by using time step sizes which are just determined by the nonstiff hyperbolic part of the system. Large time step size computations are obtained. We analyze the stability and truncation errors of the schemes. Numerical examples of both scalar equations and systems in two and three spatial dimensions are shown to demonstrate the accuracy, efficiency and robustness of the methods.
Osteochondritis Dissecans in an Appaloosa Foal Associated with Zinc Toxlcosis

Summary This report describes a severe case of osteochondritis dissecans (OCD) in a 5-month-old foal raised on a drylot contaminated with mine tailings. The high levels of zinc found in the fiver from the foal at necropsy suggest that zinc toxicity contributed to the development ofthe OCD, as previously described. However, extensive efforts to determine the source of the excess zinc in the foal's environment were unsuccessful since the feed, water, and soil all contained normal levels of zinc.
Nursing Student Anxiety as a Context for Teaching/Learning

Experiential learning in nursing programs includes role-play, simulation, and live clinical experiences. Anxiety levels can heighten during experiential learning as students attempt to gain psychomotor skills and transfer knowledge into critical thinking. Nursing students may experience anxiety that can interfere with learning and critical thinking. However, the presence of student anxiety can be used to initiate a purposeful caring transaction between nursing faculty and student. The caring transaction is a way for faculty to model both caring and presence, create experiential learning of caring by students, and lead students to initiate self-care interventions to manage anxiety through the nursing program and beyond. Multiple learning outcomes can be achieved as the students integrate faculty-modeled concepts of caring and presence into simulated or real clinical situations, reduce or manage their anxiety, and improve their clinical judgment and critical thinking skills.