cssi/SciSciGPT-SciSciNet huggingface dataset:
Simultaneous vibration reduction and energy harvesting of a nonlinear oscillator using a nonlinear electromagnetic vibration absorber-inerter

Abstract Recently, considerable attention has been given to electromagnetic resonant shunt tuned mass damper-inerters (ERS-TMDI) for simultaneous vibration mitigation and energy harvesting. The application of this design is already well-established for linear structures, however, it is not extensively explored for nonlinear structures. This work, for the first time, aims to achieve both vibration mitigation and energy harvesting for nonlinear oscillating structures using a single device. For this, a novel nonlinear electromagnetic resonant shunt tuned mass damper-inerter (NERS-TMDI) is proposed with two different configurations. The proposed NERS-TMDI is coupled to a nonlinear oscillator via linear and nonlinear springs. For the first configuration, the electromagnetic and the inerter devices are grounded on one side and connected to the nonlinear vibration absorber on the other side. In the second configuration, the electromagnetic device is placed between the nonlinear vibration absorber and the primary structure. The nonlinear governing equations of motion are solved analytically using the method of harmonic balance in conjunction with the fixed arc-length continuation method. The analytical approach is validated using numerical simulations. A detailed parametric analysis for both configurations is conducted to identify the key design parameters that render the best performance of the NERS-TMDI. The results show that the proposed NERS-TMDI configurations perform better than the existing approaches, including the nonlinear tuned mass damper (NTMD), and the ERS-TMDI, in terms of vibration control. The results also show that the first configuration of NERS-TMDI always performs better for simultaneous vibration mitigation and energy harvesting than the second configuration of NERS-TMDI. This implies that grounding the electromagnetic transducer extends the range of effectiveness of the NERS-TMDI. Further, a sensitivity analysis on the optimal Configuration-1 showed that the NERS-TMDI is robust to variations in nonlinear stiffness, but its performance degrades for variations in inertance, resistance, inductance, and capacitance. Additionally, a parametric study demonstrates that higher values of nonlinear stiffness, inertance, and resistance, and lower values of inductance and capacitance render an optimal design of the Configuration-1 of the NERS-TMDI for energy harvesting. The findings are very promising and open a horizon of future opportunities to optimize the design of the NERS-TMDI for superior performance.
Optimal Rates for Learning Hidden Tree Structures

We provide high probability finite sample complexity guarantees for hidden non-parametric structure learning of tree-shaped graphical models, whose hidden and observable nodes are discrete random variables with either finite or countable alphabets. We study a fundamental quantity called the (noisy) information threshold, which arises naturally from the error analysis of the Chow-Liu algorithm and, as we discuss, provides explicit necessary and sufficient conditions on sample complexity, by effectively summarizing the difficulty of the tree-structure learning problem. Specifically, we show that the finite sample complexity of the Chow-Liu algorithm for ensuring exact structure recovery from noisy data is inversely proportional to the information threshold squared (provided it is positive), and scales almost logarithmically relative to the number of nodes over a given probability of failure. Conversely, we show that, if the number of samples is less than an absolute constant times the inverse of information threshold squared, then no algorithm can recover the hidden tree structure with probability greater than one half. As a consequence, our upper and lower bounds match with respect to the information threshold, indicating that it is a fundamental quantity for the problem of learning hidden tree-structured models. Further, the Chow-Liu algorithm with noisy data as input achieves the optimal rate with respect to the information threshold. Lastly, as a byproduct of our analysis, we resolve the problem of tree structure learning in the presence of non-identically distributed observation noise, providing conditions for convergence of the Chow-Liu algorithm under this setting, as well.
Representation over time : The effects of temporal distance on similarity

Similarity is central in human cognition, playing a role in a wide range of cognitive processes. In three studies, we demonstrate that subjective similarity may change as a function of temporal distance, with some events seeming more similar when considered in the near future, while others increase in similarity as temporal distance increases. Given the ubiquity of inter-temporal thought, and the fundamental role of similarity, these results have important implications for cognition in general.
A quality assessment of YouTube content on shoulder instability.

Objectives The Internet is a widely used resource for patients seeking health information, yet little editing or regulations are imposed on posted material. We sought to assess the quality and accuracy of information presented on shoulder instability on the online video platform YouTube. We hypothesize that YouTube videos concerning shoulder instability will be of little quality, accuracy, and reliability. Methods The first 50 YouTube videos resulting from the keyword query 'shoulder instability' were analyzed. The Journal of American Medical Association (JAMA) benchmark criteria (score range, 0-4) was used to assess video accuracy and reliability, and the Global Quality Score (GQS; score range, 0-5) was used to assess the quality of the video's educational content along with a generated Shoulder-Specific Score (SSS). Results The 50 videos observed collectively had 5,007,486 views, with the mean number of views being 100,149.72 ± 227,218.04. Of all videos observed, 32% were from a medical source and 56% had content relating to pathology information. The mean JAMA score was 2.84 ± 0.74, with the highest scores coming from academic sources. The mean GQS and SSS scores were 2.68 ± 0.84 and 5.30 ± 3.78. The mean GQS score was highest in videos from medical sources (3.3 ± 0.8) and videos about surgical technique/approach (3.2 ± 1.1). Advertisements were negative predictors of the JAMA score (β = -0.324, P = 0.014), and academic (β = 0.322, P = 0.015) and physician sources (β = 0.356, P = 0.008) were positive predictors. Conclusion YouTube videos on shoulder instability are of low quality and accuracy and are not reliable. Care providers should be aware of the overall low quality of information available on YouTube regarding shoulder instability.
(Re)Imagining Multilingual Learners: Using Photo Stories to Honor Students’ Strengths, Interests, and Experiences

The labeling of students has the potential to result in deficit thinking, which can cause classrooms to become sites of limitation instead of places of limitless opportunity for students. This article discusses the literacy strategy of creating photo stories and shares the steps involved in inviting students to create personal photo stories that honor students’ lived experiences. The author shares how these photo stories have the potential to promote critical and productive dialogue among educators and students to help them celebrate the diverse languages, cultures, interests, and life experiences that are present in their classrooms. Keywordslabels, deficit thinking, multilingual learners, photo story
Proteins of chromatin in template restriction: III. The macromolecules in specific restriction of the chromatin DNA

Abstract Macromolecules influencing the tissue-specific restriction of DNA in chromatin from rat liver and thymus were studied. It was found that the specificity of RNA synthesis in vitro (as detected by DNA-RNA hybridization) can be changed from the pattern characteristic for rat liver to that of rat thymus and vice versa by exchanging the nonhistone proteins associated with the DNA in chromatin and reconstituting this fraction back to the DNA and histones by gradient dialysis. The origin of the histones did not contribute to the specificity of DNA restriction in isolated and reconstituted chromatin. Even the reconstitution of calf thymus histones to dehistonized rat liver chromatin did not alter the specificity of RNA normally synthesized by rat liver chromatin templates.
Relativistic dynamics and the deuteron axial form factor

Matrix elements of the deuteron axial current are calculated in the covariant spectator scheme of Gross, and compared to a corresponding calculation using light-front dynamics. The results confirm the dominant role in both approaches of the deuteron D state in observable effects beyond the nonrelativistic limit. {copyright} {ital 1997} {ital The American Physical Society}
Prediction of Pre-ignition Reactivity and Ignition Delay for HCCI Using a Reduced Chemical Kinetic Model

Homogeneous Charge Compression Ignition (HCCI) engines have the possibility of low NOx and particulate emissions and high fuel efficiencies. In HCCI the oxidation chemistry determines the auto-ignition timing, the heat release rate, the reaction intermediates, and the ultimate products of combustion. This paper reports an initial effort to apply our reduced chemical kinetic model to HCCI processes. The model was developed to study the pre-ignition characteristics (pre-ignition heat release and start of ignition) of primary reference fuels (PRF) and includes 29 reactions and 20 active species. The only modifications to the model were to make the proscribed adjustments to the fuel specific rate constants, and to enhance the H2O2 decomposition rate to agree with published data. Simulations were compared with measured and calculated data from our engine operating at the following conditions: speed - 750 RPM, inlet temperature - 393 K to 453 K, fuels - 20 PRF, 50 PRF and 20 PRF with alkenes and aromatics, and equivalence ratio - 0.4 and 0.5. The simulations are in good agreement with the experimental data including temperature, pressure, ignition delay, and preignition heat release. This demonstrates the model has potential for use in predicting the behavior of HCCI engines. From both the experiments and the reduced kinetic model, the results show that for 20 PRF the first–stage ignition begins at 707 K, the second-stage ignition temperature is 910-924 K, and significant reaction occurs during the preignition process resulting in pre-ignition heat release of about 7%-10% of the potential heat release. The second-stage ignition time varies with inlet temperature, equivalence ratio, engine load and octane number. When the engine is run with a volumetric efficiency of 71% at 750 RPM, inlet temperature 423 K, equivalence ratio 0.4 and 20 PRF, the duration from the first to second-stage ignition is 25 CAD.
A Gentle Introduction to Multi-stage Programming, Part II

As domain-specific languages (DSLs) permeate into mainstream software engineering, there is a need for economic methods for implementing languages. Following up on a paper with a similar title, this paper focuses on dynamically typed languages, covering issues ranging from parsing to defining and staging an interpreter for an interesting subset of Dr. Scheme. Preliminary experimental results indicate that the speedups reported in previous work for smaller languages and with smaller benchmarks are maintained.
Experimental chemotherapy and approaches to drug discovery for Trypanosoma cruzi infection.

In the 100 years since the discovery of Chagas disease, only two drugs have been developed and introduced into clinical practice, and these drugs were introduced over 40 years ago. The tools of drug discovery have improved dramatically in the interim; however, this has not translated into new drugs for Chagas disease. This has been largely because the main practitioners of drug discovery are pharmaceutical companies who are not financially motivated to invest in Chagas disease and other “orphan” diseases. As a result, it has largely been up to academic groups to bring drug candidates through the discovery pipeline and to clinical trials. The difficulty with drug discovery in academia has been the challenge of bringing together the diverse expertise in biology, chemistry, and pharmacology in concerted efforts towards a common goal of developing therapeutics. Funding is often inadequate, but lack of coordination amongst academic investigators with different expertise has also contributed to the slow progress. The purpose of this chapter is to provide an overview of approaches that can be accomplished in academic settings for preclinical drug discovery for Chagas disease. The chapter addresses methods of drug screening against Trypanosoma cruzi cultures and in animal models and includes general topics on compound selection, testing for drug-like properties (including oral bioavailability), investigating the pharmacokinetics and toxicity of compounds, and finally providing parameters to help with triaging compounds.
Membrane bistability in olfactory bulb mitral cells.

Whole-cell patch-clamp recordings were used to investigate the electrophysiological properties of mitral cells in rat main olfactory bulb brain slice preparations. The majority of mitral cells are bistable. These cells spontaneously alternate between two membrane potentials, separated by ∼10 mV: a relatively depolarized potential (upstate), which is perithreshold for spike generation, and a relatively hyperpolarized potential (downstate), in which spikes do not occur. Bistability occurs spontaneously in the absence of ionotropic excitatory or inhibitory synaptic inputs. Bistability is voltage dependent; transition from the downstate to the upstate is a regenerative event activated by brief depolarization. A brief hyperpolarization can switch the membrane potential from the upstate to the downstate. In response to olfactory nerve (ON) stimulation, mitral cells in the upstate are more likely to fire an action potential than are those in the downstate. ON stimulation can switch the membrane potential from the downstate to the upstate, producing a prolonged and amplified depolarization in response to a brief synaptic input. We conclude that bistability is an intrinsic property of mitral cells that is a major determinant of their responses to ON input.
The Fundamental Challenge of Product Design

Product design practice is an evolving art form. We have made tremendous improvement in methods for and execution of the process in recent years. Yet the challenge of environmental sustainability of products is one area where design practice remains largely in the dark ages. This essay argues that we need to embrace the imperative of design for environment and must evolve design practices to address this challenge.
Solar XUV grazing incidence spectrograph on Skylab.

The objective of Skylab corollary experiment S020 was to obtain through the availability of long exposure times more complete information than was then available on the extreme ultraviolet (XUV) and soft x-ray spectrum of the sun in the 10–200-A range. The instrument was a small grazing incidence spectrograph with photographic recording. Use was made of a novel split-ruled grating that combined 1200- and 2400-1/mm rulings to double the spectral coverage of the instrument and to aid in the measurement of wavelengths and order sorting. As it happened, there were many difficulties resulting from the major problems encountered by the Apollo and Skylab missions. Useful spectra were obtained, but the sensitivity of the instrument was greatly reduced, probably because of contamination resulting from leakage of the fluid used in the spacecraft cooling system.
Reliability of high temperature electronic components

A review is given of high temperature reliability efforts on solid-state electronic components. To date, most of this work has been concerned with high temperature stressing, usually for short periods of time (less than 100 hours) to demonstrate stability. To field high temperature devices in the future, comprehensive high temperature reliability studies will be required.
α-Hydroxylation of a Ketone Using o-Iodosylbenzoic Acid: α-Hydroxyacetophenone via the α-Hydroxy Dimethylacetal

α-Hydroxylation of a ketone using o-iodosylbenzoic acid: α-hydroxyacetophenone via the α-hydroxy dimethylacetal reactant: Anhydrous methanol (80 mL) product: α-Hydroxyacetophenone. intermediate: 6.0 g (0.33 mol) of α-hydroxy dimethylacetal Keywords: acetal (and thioacetal) formation; hydrolysis, acetals and ketals; hydroxylation; oxidation, CH2 CHOH and CHOR; methanol
Building assets from birth: a global comparison of Child Development Account policies

Asset building is a growing theme in public policy, and building assets from birth in the form of Child Development Accounts is now occurring in several countries. This article provides an overview of the Child Development Account policies in Singapore, Canada, the UK and Korea, and the proposed policy in the USA. The key elements of inclusiveness, progressivity, coherence and integration, and development are explicated and discussed.
Determination of water in volcanic glasses by Karl-Fischer titration

Abstract A method is described for the routine measurement of dissolved water in crushed and sieved volcanic glasses utilizing Karl-Fischer titration and sample pyrolysis without the addition of a flux. Sample fragments between 75 and 150 μm in size proved to be desirable for rapid measurements at low water contents because complete degassing is achieved without significant water adsorption. However, adsorbed water was found in all ground samples after long-term storage, illustrating the need for prompt water analyses after crushing. Estimates of analytical precision were based upon replicate measurements of natural rhyolitic and basaltic glasses. Results indicate a relative standard deviation for this method of 1.5 wt.%) water contents. The ease of sample analysis and good analytical precision make this technique quite useful for geologic interpretation of volcanic processes. Detection limits depend upon sample size but were estimated to be 60 ppm for a 1-g sample.
Review of Open Access: What You Need to Know Now

Open access is a very hot topic and its important issues and aspects are succinctly covered by Walt Crawford in this special report. Geared toward librarians, this book is a good introduction to wh...
Reflective tomography reconstruction of satellite features-field results.

We report on the first satellite feature reconstruction, to our knowledge, by use of range-resolved reflective tomography techniques from nonimaging laser radar data collected on an orbiting satellite. The reconstructed features were two retroreflectors mounted on a satellite. The data were collected with a coherent laser radar system located at the Maui Space Surveillance Site in Maui, Hawaii. We utilized a filtered backpropagation algorithm to reconstruct the images using intensity projections created from the raw data. Key components of the image reconstruction process included the calculation of tomographic angles, the alignment of the intensity projections to an appropriate center of rotation, and compensation for the lack of data for a full 360° set of views.
Diabetogenic role of insulin's counterregulatory hormones in the isletectomized, diabetic goby.

In an experimental model of insulin-dependent diabetes mellitus (IDDM) in the teleost fish, the goby Gillichthys mirabilis, an isletectomy procedure completely removes the pancreatic endocrine tissue without affecting the exocrine acini or other essential tissues. Interestingly, isletectomized (Ix) gobies do not exhibit a significant hyperglycemia until 10–15 d after this procedure, suggesting a lack of initial diabetogenic actions of a pancreatic factor(s). Administering exogeneous glucagon in otherwise nonsymptomatic 7-d Ix gobies, however, induces a hyperglycemic state comparable to that in severely diabetic rats or gobies (after 20 d post-Ix). The spontaneously arising hyperglycemia observed between 10 and 15d post-Ix, on the other hand, is significantly correlated with increasing serum cortisol concentrations, with both exhibiting sustained elevated levels (approx 23 mmol/L and >100 ng/mL, respectively) at 20- and 25-d post-Ix. Exogenous cortisol treatment also significantly induced hyperglycemia in nonsymptomatic, 7-d Ix gobies. By contrast, growth hormone (GH) had no detectable diabetogenic effect in 7-d Ix gobies. Serum levels of ammonia, the principal nitrogenous waste in this species, were not affected by glucagon treatment but were reduced slightly by GH treatment (30% reduction; p<0.05). Cortisol treatment, on the other hand, increased ammonia levels twofold, suggesting that the glucocorticoid induces a negative nitrogen balance. These results indicate that the counterregulatory hormones—glucagon and cortisol—are effective diabetogenic factors in the Ix goby, capable of driving metabolic imbalance in this model of IDDM.
Nanoliter-scale sample preparation methods directly coupled to PMMA-based microchips and gel-filled capillaries for the analysis of oligonucleotides

We are currently developing miniaturized, chip-based electrophoresis devices fabricated in plastics for the high speed separation of oligonucleotides. One of the principal advantages associated with these devices is their small sample requirements, typically in the nanoliter to sub-nanoliter range. Unfortunately, most standard sample preparation protocols, especially for oligonucleotides, are done off-chip on a microliter-scale. Our work has focused on the development of capillary nano-reactors coupled to micro-separation platforms, such as micro-electrophoresis chips, for the preparation of sequencing ladders and also, PCR reactions. These nano-reactors consist of fused silica capillary tubes (length equals 10 - 20 cm; id equals 20 - 50 micrometer) with fluid pumping accomplished using the electro-osmotic flow generated by the tubes. These reactors were situated in fast thermal cyclers to perform cycle sequencing or PCR amplification of the DNAs. The reactors were interfaced to the micro-electrophoresis chips via capillary connectors micromachined in polymethylmethacrylate (PMMA) using deep X- ray etching (width equals 50 micrometer; depth equals 50 micrometer) and were situated directly on the PMMA-based microchip. This chip also contained an injector, separation channel (length equals 6 cm; width equals 30 micrometers; depth equals 50 micrometers) and a dual fiber optic, near- infrared fluorescence detector. The sequencing nano-reactor used surface immobilized templates attached to the wall via a biotin:streptavidin:biotin linkage produced by PCR using a biotinylated forward primer. Sequencing tracks could be directly injected into gel-filled capillary tubes with minimal degradation in the efficiency of the separation process. The nano-reactor could also be configured to perform PCR reactions by filling the capillary tube with the PCR reagents and template. After thermal cycling, the PCR cocktail could be injected into a capillary tube or a micro-chip device for fractionation. In all cases, the detection of the oligonucleotides was accomplished using ultra-sensitive near- IR fluorescence detection.
“Make Me Feel at Ease and at Home”: Differential Care Preferences of Nursing Home Residents

Purpose of the Study: Assessing and honoring older adults ’ preferences is a fundamental step in providing person-centered care in long-term care facilities. Researchers and practitioners have begun to develop measures to assess nursing home (NH) residents’ everyday preferences. However, little is known about how residents interpret and conceptualize their preferences and what specific clinical response may be needed to balance health and safety concerns with preferences. Design and Methods: W e used content analysis to examine interview responses on a subset of eight open-ended items from the Preferences of Every-day Living Inventory for Nursing Home (PELI-NH) residents with 337 NH residents (mean age 81). We considered how residents self-define various preferences of care and the associated importance of these preferences. Results: R esidents identified preferences for interpersonal interactions (greetings, staff showing care, and staff showing respect), coping strategies, personal care (bathroom needs, setting up bedding), and healthcare discussions. Respondents highlighted specific qualities and characteristics about care interactions that are necessary to fully meeting their everyday preferences. Implications: R esults contribute to an emergent body of research that utilizes patient preferences to achieve the goals of person-centered care. The complexity of these responses substantiates the use of qualitative inquiry to thoroughly assess and integrate NH resident preferences into the delivery of person-centered care.
Insights into the Sigma-1 receptor chaperone's cellular functions: a microarray report

We previously demonstrated that Sig-1Rs are critical regulators in neuronal morphogenesis and development via the regulation of oxidative stress and mitochondrial functions. In the present study, we sought to identify pathways and genes that are affected by Sig-1R. Gene expression profiles were examined in rat hippocampal neurons that had been cultured for 18 days in vitro (DIV). The cells were transduced with AAV siRNA targeting Sig-1R on DIV 10 for 7 days, followed by gene expression analysis using a rat genome cDNA array. The gene array results indicated that Sig-1R knockdown hampered cellular functions including steroid biogenesis, protein ubiquitination, actin cytoskeleton network, and Nrf-2 mediated oxidative stress. Many of the cellular components important for actin polymerization and synapse plasticity, including F-actin capping protein and neurofilaments, were significantly changed in AAV-siSig-1R neurons. Further, cytochrome c was reduced in AAV-Sig-1R neurons whereas free-radical generating enzymes including cytochrome p450 and cytochrome b-245 were increased. The microarray results also suggest that Sig-1Rs may regulate genes that are involved in the pathogenesis of many CNS diseases including Alzheimer's disease and Parkinson's disease. These data further confirmed that Sig-1Rs play critical roles in the CNS and thus these findings may aid in future development of therapeutic treatments targeting neurodegenerative disorders.
Distribution of western beaufort sea polychaetous annelids

Depth and depth-related processes appear to exert primary control over the distributional patterns of species of polychaetous annelids in the western Beaufort Sea (Cape Halkett to Barter Island, Alaska). Species richness and total polychaete abundance are maximal along the outer continental shelf and upper continental slope. Stations exhibiting the most similar polychaete assemblages are located at similar depths. However, some species distributions appear to correlate better with sediment type than with depth. Maximum abundance occurs deeper on the continental slope to the west, and station clusters generated by non-hierarchical clustering (using the dominant polychaete species data) are not sorted strictly by depth. In a canonical analysis of discriminance, the station clusters were projected onto a two-dimensional plane in “species space”. The first and second canonical variables of the station clusters correlate with sediment grain-size distributions, suggesting a relationship between polychaete distribution patterns and the sedimentary environment. This relationship is further substantiated when sediment grain-size distributions for each station are plotted on a tertiary diagram: the stations are grouped and ordered in a pattern similar to that generated by the canonical analysis of discriminance.
Multiplicity-Free Products of Schur Functions

We classify all multiplicity-free products of Schur functions and all multiplicity-free products of characters of SL(n; C).
Space Collaboration, and the Credible City: Academic Work in the Virtual University

Collaboration, greatly facilitated by advanced telecommunication networks, has become a dominant mode of conducting academic work. However, when collaborators meet in both physical and “electronic” spaces there are a number of unexamined costs that go with the efficiency and inclusiveness made possible by easy telecommunication-based exchanges. This article asks collaborators to be sensitive to the role that physical space plays in creative human endeavors, and to consider the impact on work accomplished in merged electronic and physical work environments. A history of city space and university space are presented within Richard Sennett's notion of exposure: a delicate balance of fear and stimulation associated with community. The concluding section of this article considers how to build the collaborative university so that the pleasures of physical space are preserved, and the efficiencies of reaching across distances with telecommunications can be leveraged. The article's coda presents a case study, and efforts are made to use hypermedia's attributes to improve the collaboration between author and reader.
Returning pediatric athletes to play after concussion: the evidence (or lack thereof) behind baseline neuropsychological testing

When and how athletes should return to play (RTP) after a concussion is still not evidence-based. As such, various and conflicting opinions about sport-related concussion management continue to be offered by individual experts, consensus groups and practitioners. As neuropsychologists, we are especially interested in the role neuropsychological testing should play in the RTP decision. Conventional neuropsychological assessment is a well-established method for evaluating individuals who have neurodevelopmental problems or acquired central nervous system insult. Neuropsychological assessment can objectively identify cognitive, psychosocial and achievement difficulties and assist with differential diagnosis and clinical and educational management. Using neurocognitive testing for the specific purpose of making RTP decisions has been popularized through a ‘baseline testing’ model. The model typically involves 25– 30 min of pre-season cognitive testing for athletes participating in high-risk sports and follow-up testing for those athletes who sustain a concussion during the season to determine whether they have returned cognitively to their baseline level. The test batteries were comprised originally of paper-and-pencil instruments, although several computerized tests are now commercially marketed and probably more commonly used. In theory, psychometric testing within a baseline model is quite appealing, because it has the potential to provide objective information about whether a child has recovered from a concussive injury. However, before the model is recommended, we believe two essential questions must be answered: (i) Do the tests have adequate statistical and methodological properties for the proposed use? and (ii) Does such testing actually improve real-life outcomes for young concussed athletes?
Low-Income Parents: How Do Working Conditions Affect Their Opportunity to Help School-Age Children At Risk?:

Numerous studies have documented the importance of parental involvement to children's success at school. Much of the discussion about what influences the outcomes of poor children has assumed that low-income parents have the same opportunity to help with their children's education. Yet, parents' availability to be involved with their children's education is often determined by job benefits and working conditions. The goal of this article is to examine empirically whether low-income working parents face significantly different nonfinancial barriers to parental involvement than those faced by higher income working parents. In particular, we examine the working conditions faced by parents who have at least one child who is in need of help because of educational or behavioral problems. Data from the National Longitudinal Survey of Youth––Mother and Child Surveys (NLSY) on 1, 878 families where mothers worked more than 20 hr per week were analyzed.
1162 NEUTROPHIL AND MACROPHAGE RESPONSES ELICITED BY MONOCLONAL ANTIBODIES AGAINST GROUP B STREPTOCOCCI

Previously we showed that type specific monoclonal antibodies of IgM and IgG2a isotypes protect against intraperitoneal(IP) infection with type III group B streptococci(GBS) in neonatal rats. In contrast, monoclonal IgA does not protect against IP GBS infection. The present study was designed to evaluate mobilization of neutrophils(PMN) and macrophages(M0) in GBS infected neonatal rats. Rats were infected IP with 106 GBS and given buffered saline or type specific IgG, IgM or IgA. Peritoneal lavage and peripheral blood counts were obtained 0, 4, 8, 12 and 20hrs postin-fection. Significantly enhanced PMN responses were seen in IgG and IgM treated rats(4hr-IgG x=38997, IgM 31957, IgA 17981; 8hr-IgG 84127, IgM 57008, IgA 43243, untreated 38120). Peritoneal M0 increased only slightly in IgG or IgM treated rats(NSD). By 20hrs peritoneal PMN in IgG or IgM treated rats actually decreased (IgG 35258; IgM 29538, untreated 46004) as GBS were cleared from blood and peritoneal cavity (GBS culture+ rats-IgG 3/8; IgM 1/6; untreated 6/6). Mobilization was also evaluated using GBS infected polyvinal sponges implanted subcutaneously. Cell recovery from sponges was significantly greater in IgG or IgM treated rats (20 hrs-GBS alone x=300 PMN/2450 M0; IgM 1950/3250; IgG 700/3600; IgA 0/2000). These results suggest that antibody protection is mediated in part by enhanced PMN mobilization to the site of infection. This local PMN response may be essential for protection of human neonates from GBS infection.
On theoretical co-existence versus theoretical integration

The issue of theoretical co-existence versus theoretical integration is addressed, considering the relation between attribution theory (AT) and internal norm theory (INT). The connection between the two theories is in part determined by the definition given by internal norm theorists to the concept of “value”. If value connotes future expectancy of success, then the theories are commensurate because they share a common prediction. Furthermore, AT links expectancy to causal stability, whereas INT associates expectancy with causal locus. Inasmuch as low ability or medical illness ascriptions for failure (internal and stable) give rise to expectations of poor future performance, INT is contradicted while AT is upheld. On the other hand, if value connotes something other than (in addition to) the likelihood of future success, such as the worth of the person, then the theories appear more complementary. However, inasmuch as AT includes a locus of causality dimension, it has the conceptual tools to embrace the contributions of INT.
Paramecium Has Two Regulatory Subunits of Cyclic AMP‐Dependent Protein Kinase, One Unique to Cilia

The subunit composition and intracellular location of the two forms of cAMP-dependent protein kinase of Paramecium cilia were determined using antibodies against the 40-kDa catalytic (C) and 44-kDa regulatory (R44) subunits of the 70-kDa cAMP-dependent protein kinase purified from deciliated cell bodies. Both C and R44 were present in soluble and particulate fractions of cilia and deciliated cells. Crude cilia and a soluble ciliary extract contained a 48-kDa protein (R48) weakly recognized by one of several monoclonal antibodies against R44, but not recognized by an anti-R44 polyclonal serum. Gel-filtration chromatography of a soluble ciliary extract resolved a 220-kDa form containing C and R48 and a 70-kDa form containing C and R44. In the large enzyme, R48 was the only protein to be autophosphorylated under conditions that allow autophosphorylation of R44. The subunits of the large enzyme subsequently were purified to homogeneity by cAMP-agarose chromatography. Both C and R48 were retained by the column and eluted with I M NaCl; no other proteins were purified in this step. These results confirm that the ciliary cAMP-dependent protein kinases have indistinguishable C subunits, but different R subunits. The small ciliary enzyme, like the cell-body enzyme, contains R44, whereas R48 is the R subunit of the large enzyme.
Organization of primary afferent axons in the trigeminal sensory root and tract of the rat.

A combination of immunocytochemical and electron microscopic methods were employed to assess the organization of the trigeminal (V) spinal tract in adult rats. Immunostaining was employed at the light microscopic level to selectively label large myelinated (by using antibodies against neurofilament protein) and small unmyelinated (by using antibodies against calcitonin gene-related peptide) primary afferents. In addition, the plant lectin Bandeiraea simplicifolia-I was employed to histochemically label small unmyelinated primary afferents. Results from these experiments indicated that larger myelinated axons were distributed throughout the cross-sectional extent of the V spinal tract (TrV), whereas smaller fibers were most numerous just below the pial surface. These results were confirmed with quantitative electron microscopy which demonstrated that the central portion of the V sensory root and TrV were composed primarily of larger myelinated fibers, whereas the periphery of the root and the portion of TrV just below the pial surface contained a higher percentage of smaller myelinated and unmyelinated axons. When considered together with results regarding the birthdates of neurochemically defined classes of V ganglion cells (White et al. [1994] J. Comp. Neurol. 350:397–411), these results suggest that TrV is laid down in a chronotopic fashion with the first axons forming its deeper portion and later arriving axons being added more superficially. © 1996 Wiley-Liss, Inc.
Low-level nitrate export from confined dairy farming detected in North Carolina streams using δ15N

Abstract Animal waste-produced nitrate in streams can be detected with natural abundance nitrogen isotopes even when stream nitrate concentrations are low and derive predominantly from natural soil nitrate sources. The objective of this limited study was to demonstrate the utility of such an approach with a minimal number of samples and minimal supporting data. These constraints are important in terms of the usefulness of the small-scale isotopic approach as a component of long-term, large-scale watershed and river basin monitoring, given the expense of nitrate isotopic measurements. The study was able to identify a small animal waste nitrate export signal over a significant background signal of soil nitrate and possible fertilizer nitrate in the stream draining the site. During the course of a year, a second-order stream adjacent to a carefully managed research dairy farm near Raleigh, NC had mean nitrate–N of 0.4 mg l−1 with mean δ 15 N –NO3 values of +8.7‰ downstream of the farm. Secondary dairy lagoon liquids used for spray irrigation of nearby fields had a mean ammonium concentration of 87.5 mg l−1, and a mean δ 15 N of +20.7‰. A small, intermittent first-order stream draining the dairy sprayfields and emptying into the second-order stream had a mean nitrate–N level of 3.7 mg l−1 and mean δ 15 N –NO3 of +16.0‰. Even at the relatively low nitrate levels and slightly elevated δ 15 N –NO3 values of the second-order receiving stream, an observed increase in δ 15 N values with increasing nitrate concentration in this stream indicates that a small amount of animal waste-produced nitrate is being exported. This type of monitoring could be applied to many small watersheds as part of a larger watershed or river basin study where sampling density is constrained by logistical and economic factors. This is the case in the Neuse River Basin, where this study was an early part of a developing basin-wide Nitrogen Isotope Tracer Program. This type of monitoring can be particularly useful where identification of targets for reduction or stabilization of N export from livestock farms is desired, and the animal waste nitrate signal is superimposed on a larger natural background nitrate or fertilizer nitrate + natural background nitrate signal.
Host Resistance to Monilinia vaccinii-corymbosi in Flowers and Fruits of Highbush Blueberry

Monilinia vaccinii-corymbosi, the causal agent of mummy berry disease, infects blueberry flowers via the gynoecial pathway. To describe the expression of host resistance in highbush blueberry (Vaccinium corymbosum), fungal growth in the styles and colonization of the locules were compared among five blueberry cultivars in a series of controlled greenhouse experiments. Styles were harvested 1 and 4 days postinoculation, and the length colonized by hyphae was determined using fluorescence microscopy. At 8 weeks after inoculation, fruit were harvested and scored for the presence of hyphae in the locules. The infection frequency of styles ranged from 0.33 to 0.71, and only cv. Weymouth had significantly lower infection frequency than the other cultivars. The mean length of the colonized portion of the stylar canal ranged from 0.126 to 0.434 mm after 1 day and 1.62 to 3.59 mm after 4 days. Hyphae in the styles of cv. Weymouth exhibited the least growth, whereas hyphae in the styles of cultivars Jersey and Rancocas were significantly longer. The distance of style penetrated for cultivars Bluecrop and Coville was intermediate. The mean disease incidence of locules differed significantly. Values for cultivars Weymouth and Jersey were the smallest (0.038 and 0.039) and largest (0.249 and 0.236), respectively. The results demonstrate that a component of resistance to infection by M. vaccinii-corymbosi is expressed during growth in the gynoecial pathway.
Diffusion-limited binary reactions: the hierarchy of nonclassical regimes for random initial conditions

Abstract We derive a hierarchy of kinetic regimes and crossover conditions for elementary A + A → 0 and A + B → 0 batch reactions from a nonclassical reaction—diffusion formalism that includes spatial fluctuations. This paper addresses the case of a spatially random initial distribution of reactants; correlated initial conditions are discussed in another paper. For low dimensions (d⩽2) we find that both A + A → 0 and A + B → 0 reactions depart (swiftly) from the classical behavior toward a “depletion zone regime” with non-Hertzian nearest neighbor distributions and nonclassical rate laws. Eventually the (A – B) density difference fluctuations take over in the A + B → 0 case and lead to the segregated Ovchinnikov—Zeldovich asymptotic behavior with its peculiar rate laws. We give scaling laws for the crossover time and crossover density, with explicit dependencies on the initial density and on the dimension. Similarly, in three dimensions the crossover from the classical to the segregated Zeldovich regime is derived for the A + B → 0 reaction. Finite size effects differ significantly for the segregated and nonsegregated regimes. In the former case we obtain a relation between aggregate sizes and lattice sizes. Monte Carlo simulations bear out the scaling laws and provide the scaling coefficients.
Quantification of bony pelvic exposure through the modified Stoppa approach.

Objectives:Authors previously have described anatomic structures commonly seen through the modified Stoppa approach; however, no study has formally quantified the areas and amount of visual bony exposure that is obtained. This information is important for proper preoperative planning of acetabulum f
Reactions of positive ions with ClN3 at 300K

Abstract The kinetics of eighteen positive ions with chlorine azide (ClN3) have been studied using a selected ion flow tube (SIFT). These measurements allowed for the estimation of both the ionization energy, >930 kJ mol−1 (>9.6 eV), and the proton affinity, 713 ± 41 kJ mol−1, of chlorine azide. Reaction rate constants have been determined. Product ions have been identified, and quantified when synthetic complications allowed. In addition, general reaction trends have been observed. A reaction coordinate diagram for the novel reaction of N+ with ClN3 is discussed.
Hole plasmon excitations on a p-type GaAs(110) surface.

High-resolution electron-energy-loss spectroscopy (HREELS) is used to study the hole-plasmon excitations in the valence band of heavily doped p-type GaAs(110) surfaces (${\mathit{n}}_{\mathit{H}}$=2.2\ifmmode\times\else\texttimes\fi{}${10}^{19}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$). A single well-defined surface-hole-plasmon peak at an energy of 75 meV was observed by HREELS at low temperature (-80 K). The observed peak is attributed to a coherent excitation of both the light- and heavy-hole plasmas, and its energy position is higher than that expected for either the light-hole or heavy-hole surface plasmon. We demonstrate that the large peak width of the hole-plasmon excitation, for a heavily doped p-type GaAs surface, is due to the low electronic mobility of holes.
The Effect of Smoking on Serum IgG2 Reactive With Actinobacillus actinomycetemcomitans in Early-Onset Periodontitis Patients*

High titers of serum IgG2 reactive with Actinobacillus actinomycetemcomitans are present in early-onset periodontitis (EOP) patients and it appears that anti-A. actinomycetemcomitans may be protective. Smoking is associated with increased periodontal disease severity in generalized early-onset periodontitis (G-EOP) patients, but is not associated with periodontal disease severity in patients with localized juvenile periodontitis (LJP). Furthermore, smoking is associated with reduced serum IgG2 levels in black patients with G-EOP but not in those with LJP. Based on this selective effect of smoking, we hypothesized that smoking would be associated with a reduction of specific IgG2 reactive with A. actinomycetemcomitans in black G-EOP patients but not black LJP patients. In addition, we examined IgG2 responses to carbohydrate antigens from non-periodontal pathogens including Haemophilus influenzae b oligosaccharide antigen (Hib) and the Streptococcus pneumoniae antigen phosphocholine (PC). Smoking status was assessed from serum cotinine levels, and IgG2 specific for A. actinomycetemcomitans, Hib, and PC was assessed by ELISA. Our study revealed that smoking was correlated with a dramatic reduction in serum IgG2 anti-A. actinomycetemcomitans in G-EOP smokers but not in LJP smokers. In contrast, anti-Hib IgG2 and anti-PC IgG2 were not affected in either G-EOP or LJP patients. In short, these results indicate that smoking is associated with a reduction in serum IgG2 anti-A. actinomycetemcomitans in black G-EOP subjects, but IgG2 reactive with other antigens may not be reduced in G-EOP smokers.
Differentiation of mucous membrane pemphigoid subgroups with confocal imaging.

Objective Mucous membrane pemphigoid is an immune-mediated subepithelial blistering disease consisting of immunologically heterogeneous subgroups. Differentiation between these subgroups is important because they differ in prognosis. This study uses oral mucosal pemphigoid specimens to investigate the utility of computer-aided fluorescence overlay antigen mapping and laser scanning confocal microscopy to differentiate subgroups of mucous membrane pemphigoid. Study design Thirty oral mucosal biopsy specimens were cryosectioned and immunostained, although only 13 could be analyzed due to technical difficulties. In vivo bound antibodies and molecular markers of the basement membrane zone were differentially labeled with fluorescent antibodies. Fluorescent signals were imaged, and the spatial localization of in vivo bound antibodies was compared with the markers and analyzed. Results In vivo bound IgG antibodies colocalized with β4-integrin in 3 cases, with laminin-5 in 8 cases, and with collagen VII in 2 cases. Conclusion Fluorescence overlay antigen mapping and laser scanning confocal microscopy are useful techniques to differentiate pemphigoid subgroups in oral biopsy specimens.
Aneuploidy and cancer.

Numeric aberrations in chromosomes, referred to as aneuploidy, is commonly observed in human cancer. Whether aneuploidy is a cause or consequence of cancer has long been debated. Three lines of evidence now make a compelling case for aneuploidy being a discrete chromosome mutation event that contrib