cssi/SciSciGPT-SciSciNet huggingface dataset:
Development of wastewater pooled surveillance of SARS-CoV-2 from congregate living settings

Abstract Wastewater-based monitoring for SARS-CoV-2 holds promise as tool to inform public health-decision making. Testing at individual building-level could be an efficient, passive means of preventing early detection of new cases in congregate living settings, but this approach has not been validated. Sample collection protocols were developed and refined during preliminary sampling from a hospital and a local municipal wastewater treatment plant. Molecular diagnostic methods were compared side-by-side to assess feasibility, performance and sensitivity. Optimized sample collection and processing protocols were then used to monitor two occupied dormitory complexes (n=105 and 66) over eight weeks. Wastewater results were validated using known case counts from external clinical testing of building occupants. Results confirm that ultracentrifugation from a 24 hour composite collection had a sensitivity of 95% and a specificity of 100%. However, if the detection of convalescent shedding is considered a false positive then the sensitivity would be 95.2% but the specificity would drop to 52%. We determined a highly sensitive method for detecting SARS-CoV-2 shedding in building wastewater however our methods could not distinguish new infectious cases from persistent convalescent shedding of SARS-CoV-2 RNA. Future work must focus on methods to distinguish new infections from convalescent shedding to widely deploy this promising wastewater surveillance tool.
Modeling Ground-Air Wireless Connectivity: Continuous Connection Probability Analysis

In this paper, we consider three ground-aircraft communication issues, namely, ground-centric connectivity, aircraft-centric connectivity, and link capacity analysis. Particularly, we propose the continuous connection probability over at least $\tau $ seconds, termed as $\tau $ -connectivity, for the ground-centric link and aircraft-centric link respectively, which are derived in the expression of several key parameters such as the aircraft/ground station density, the aircraft velocity, and the connectable elevation angle threshold. Theoretical tradeoff between ergodic outage capacity and the number of connected aircraft is analyzed for low and high transmit power regimes. The hypotheses in the ground-centric $\tau $ -connectivity model are tested, and we observe a good match between the theoretic probability and the real world data-based probability although some real world aircraft statistic characters do not match the ideal assumption perfectly. Next, the aircraft-centric $\tau $ -connectivity is analyzed theoretically. Approximate yet practically accurate closed form aircraft-centric connection probabilities are derived and verified with Monte Carlo simulations. Furthermore, considering atmospheric gas and cloud attenuation, we compare the link budget and capacity between the ground-centric ground-to-aircraft link and the ground-to-satellite link under the $\tau $ -connectivity and demonstrate the advantage of ground-aircraft communication.
Urban, Low-Income, African American Parents' Experiences and Expectations of Well-Child Care.

Abstract Purpose Well-child care is the foundation of pediatric health promotion and disease prevention. Primary care quality is lower for low-income and African American children compared to white children, and social determinants have an increasingly acknowledged impact on child health. Ensuring that high-quality well-child care fulfills its potential to mitigate the negative effects of social determinants on African American children is imperative. This study provides an understanding of urban, low-income, African American well-child care experiences and expectations. Design and methods A qualitative, focus group method was used. A purposive, volunteer sample of low-income, African American parents with children birth to age five was recruited from St. Louis and Milwaukee. Focus groups were held in convenient, community sites. Data was audio-digitally recorded. Transcribed data were coded and analyzed through inductive content analysis. Results Thirty-five caregivers, 86% females, participated in four focus groups. Categories (and sub-categories) identified include: Community factors (We want better schools, It's getting more rough where I live); Sources of parenting advice (Google it, Call your parent, Older remedies); System challenges (Cost, Frequent new faces, Politics); Challenges with providers (Couldn't help me, Missed something important, Treated differently, Are you really listening?); Anticipatory guidance (Breastfeeding, Discipline, Vaccines, Development); and What parents desire (Know them, trust). Conclusions This study reveals the contexts that give rise to health care disparities and provides insight into parent's healthcare behaviors. Practice implications Results offer providers guidance in providing well-child care for this population to improve pediatric care quality and child health.
Functionalized carbon nanotube doped gel electrolytes with enhanced mechanical and electrical properties for battery applications

Abstract We report the functionalized carbon nanotubes (fCNTs) and graphene oxide (GO) doped polyvinyl alcohol (PVA) based gel electrolytes (GEs). The multiwalled carbon nanotubes (CNTs) were treated via microwave irradiation to alter the degree of carboxylation. The fCNT doped gel electrolyte (fCNTGE) showed significantly improved ionic conductivity, mechanical strength as well as electrochemical stability when compared to the pure GE and graphene oxide doped gel electrolyte (GOGE). The homogeneous distribution of ionic channels provided by fCNTs served as redox shuttle and facilitated the ion migration in the gel. The fCNTGE exhibited the best performance when the oxygen content was 12.8% by weight. The ionic conductivity was significantly improved by introducing fCNTs into the PVA gel and reached 6.9 × 10−2 S cm−1, revealing that the diffusion and transport of ions into electrolyte were much better than the GE and GOGE. A significant enhancement in the gel mechanical properties was observed as the Young's module (E = 2.3) and tensile strength (22.3 kPa) of fCNTGE was higher than that of GE and GOGE. Furthermore, the composite Zn–Ag2O batteries were made and tested using the fCNTGE, GE, and GOGE in the 3D-printed battery casings. The fCNTGE based batteries demonstrated good electrochemical stability with specific capacity reaching 204.3 mAh g−1 (C/20).
Microbial Abundance and Diversity in Subsurface Lower Oceanic Crust at Atlantis Bank, Southwest Indian Ridge.

International Ocean Discovery Program Expedition 360 drilled Hole U1473A at Atlantis Bank, an oceanic core complex on the Southwest Indian Ridge, with the aim of recovering representative samples of the lower oceanic crust. Recovered cores were primarily gabbro and olivine gabbro. These mineralogies may host serpentinization reactions that have the potential to support microbial life within the recovered rocks or at greater depths beneath Atlantis Bank. We quantified prokaryotic cells and analyzed microbial community composition for rock samples obtained from Hole U1473A and conducted nutrient addition experiments to assess if nutrient supply influences the composition of microbial communities. Microbial abundance was low (≤104 cells cm-3) but positively correlated with the presence of veins in rocks within some depth ranges. Due to the heterogeneous nature of the rocks downhole (alternating stretches of relatively unaltered gabbros and more significantly altered and fractured rocks), the strength of the positive correlations between rock characteristics and microbial abundances was weaker when all depths were considered. Microbial community diversity varied at each depth analyzed. Surprisingly, addition of simple organic acids, ammonium, phosphate, or ammonium plus phosphate in nutrient addition experiments did not affect microbial diversity or methane production in nutrient addition incubation cultures over 60 weeks. The work presented here from Site U1473A, which is representative of basement rock samples at ultraslow spreading ridges and the usually inaccessible lower oceanic crust, increases our understanding of microbial life present in this rarely studied environment and provides an analog for basement below ocean world systems such as Enceladus. IMPORTANCE The lower oceanic crust below the seafloor is one of the most poorly explored habitats on Earth. The rocks from the Southwest Indian Ridge (SWIR) are similar to rock environments on other ocean-bearing planets and moons. Studying this environment helps us increase our understanding of life in other subsurface rocky environments in our solar system that we do not yet have the capability to access. During an expedition to the SWIR, we drilled 780 m into lower oceanic crust and collected over 50 rock samples to count the number of resident microbes and determine who they are. We also selected some of these rocks for an experiment where we provided them with different nutrients to explore energy and carbon sources preferred for growth. We found that the number of resident microbes and community structure varied with depth. Additionally, added nutrients did not shape the microbial diversity in a predictable manner.
Two Explanations of Temporal Changes in Ability-Skill Relationships: A Literature Review and Theoretical Analysis

Abstract : The report reviews and integrates the empirical and theoretical literature relevant to the temporally decreasing predictive relationship between ability measures and complex motor task performance. An extensive historical review of complex motor skill learning revealed that two distinct theoretical models have been advanced. Both of these models, the changing task and the changing subject models, adequately account for this predictive decay. One model assumes that changes occur within the task structure; i.e., changes occur in the relative importance of abilities in determining performance. The other assumes that the ability levels themselves change within a fixed task structure. This paper presents a third model, a combination of the first two, and discusses the need for empirical evidence allowing a choice among the three models. (Author)
Parameterized Model Checking of Ring-Based Message Passing Systems

The Parameterized Model Checking Problem (PMCP) is to decide whether a temporal property holds for a uniform family of systems, Un, comprised of finite, but arbitrarily many, copies of a template process U. Unfortunately, it is undecidable in general [3]. In this paper, we consider the PMCP for systems comprised of processes arranged in a ring that communicate by passing messages via tokens whose values can be updated at most a bounded number of times. Correctness properties are expressed using the stuttering-insensitive linear time logic LTL∖X. For bidirectional rings we show how to reduce reasoning about rings with an arbitrary number of processes to rings with up to a certain finite cutoff number of processes. This immediately yields decidability of the PMCP at hand. We go on to show that for unidirectional rings small cutoffs can be achieved, making the decision procedure provably efficient. As example applications, we consider protocols for the leader election problem.
Relevant Research Areas and Organizational Questions Relative to Federal-State Research Programs in the Economics of Agricultural Production

In dealing with the subject of federal-state research programs, I shall summarize areas and topics for research as visualized by some of those engaged in production economics research in the southern region, and raise some questions relative to organization for Federal-State cooperation on research programs.Complicating the problem of coordination of effort is the traditional compartmentalization of research and the entanglement one often encounters in administrative procedures when encroaching into areas and topics of research claimed by others.
Trend analysis of upper stratospheric Umkehr ozone data for evidence of turnaround

[1] Recent upper stratospheric (∼35–45 km) Umkehr ozone data from three high-quality stations have been examined, with residual and change-in-trend analyses performed. These data show a consistent feature of mildly positive tendency in values for the recent several years. Trend analyses of these data yield significant positive change-in-trend estimates of about 0.75% per year since 1996 relative to negative trends of about −0.55% per year existing prior to 1996, leading to a (nonsignificant) estimate of about 0.2% per year positive trend for the recent 5-year period since the 1996 change-in-trend date.
A local meshless method for approximating 3D wind fields

AbstractAn efficient, mesh-free numerical method has been developed for creating 3D wind fields using data from meteorological towers. Node points are placed within a region of interest, generally based upon topological features. Since meshless methods do not require connective mesh generation, storage is greatly reduced, permitting implementation of the code using MATLAB on a personal computer. Utilizing locally collocated nodes and radial basis functions, a 3D wind can be quickly created that satisfies mass consistency. The meshless method yields close approximations to results obtained with mesh-dependent finite-difference, finite-volume, and finite-element techniques.
Single-phase three-stage SST modeling using RTDS for controller hardware-in-the-loop application

In order to develop and validate smart grid technologies with complex control and communication, detailed modeling of distribution systems using the Real Time Digital Simulator (RTDS) is invaluable [1]. At the distribution system level, testing a 13 kV power electronic device without first validating its controls is cost prohibitive. RTDS provides a cost effective way to study smart grids at not only the system level but also at the device level. The difficulty of modeling the distribution system using RTDS lies in the power electronic devices in the system such as single-phase three-stage solid state transformers (SST) and distributed energy storage devices (DESD) due to their fast transients. This paper investigates the low-loss two-level VSC bridge (LEV2) switching model in RTDS and solves the artificial loss problem for single phase systems. Then, the modeling method is applied to a controller hardware-in-the-loop (CHIL) setup with an SST and DESD, showing promising results. Finally, with the actual DSP+FPGA board for control and an ARM TS7800 for communication, the SST modeled in RTDS is controlled over Ethernet.
A Mathematical Model of Zinc Absorption in Humans As a Function of Dietary Zinc and Phytate

The quantities of zinc and phytate in the diet are the primary factors determining zinc absorption. A mathematical model of zinc absorption as a function of dietary zinc and phytate can be used to predict dietary zinc requirements and, potentially, enhance our understanding of zinc absorption. Our goal was to develop a model of practical and informative value based on fundamental knowledge of the zinc absorption process and then fit the model to selected published data to assess its validity and estimate parameter values. A model of moderate mathematical complexity relating total zinc absorption to total dietary zinc and total dietary phytate was derived and fit to 21 mean data from whole day absorption studies using nonlinear regression analysis. Model validity, goodness of fit, satisfaction of regression assumptions, and quality of the parameter estimates were evaluated using standard statistical criteria. The fit had an R(2) of 0.82. The residuals were found to exhibit a normal distribution, constant variance, and independence. The parameters of the model, A(MAX), K(R), and K(P), were estimated to have values of 0.13, 0.10, and 1.2 mmol/d, respectively. Several of these estimates had wide CI attributable in part to the small number and the scatter of the data. The model was judged to be valid and of immediate value for studying and predicting absorption. A version of the model incorporating a passive absorption mechanism was not supported by the available data.
On the effect of swarm collective behavior on human perception: Towards brain-swarm interfaces

Swarms of autonomous robots consist of a large number of simple and inexpensive units that use local communication and sensing in order to achieve a common goal. They provide improved robustness and efficiency characteristics over single agent solutions due to their interchangeability and inherent redundancy. Human-Swarm Interaction (HSI) is a relatively new field that has captured the attention of many researchers over the last decade. Efforts have mainly focused on the design of human-swarm control interfaces, neglecting significant aspects like the human perception of the swarm behavior. In this work, we attempt to address this issue by examining the perception and representation of collective behaviors of swarms at the brain level of human supervisors. More specifically, the effect of swarm cohesion on the ElectroEncephaloGraphic (EEG) activity of the human supervisor is investigated. We show that brain activity is correlated to swarm cohesion levels, which refers to spreading in the motion of the swarm agents. Moreover, we show that as the cohesion of the swarm becomes lower, the subjects are less able to discern changes in the direction of its motion. This work provides the first evidence of representation of swarm collective behaviors at the brain level, which can lead to the design of a new generation of brain-swarm control and perception interfaces.
Identification of a granulocytotropic Ehrlichia species as the etiologic agent of human disease

Six patients from northern Minnesota and Wisconsin with a febrile illness accompanied by granulocytic cytoplasmic morulae suggestive of ehrlichial infection were identified. Two patients died, and splenic granulocytes of one patient contained cytoplasmic vacuoles with organisms ultrastructurally characteristic of ehrlichiae. From one patient, a 1.5-kb DNA product was amplified by PCR with universal eubacterial primers of 16S rDNA. Analysis of the nucleotide sequence of the amplified product revealed 99.9 and 99.8% similarities with E. phagocytophila and E. equi, respectively, neither of which has previously been known to infect humans. From the variable regions of the determined sequence, a forward primer specific for three organisms (human granulocytic ehrlichia, E. phagocytophila, and E. equi) and a reverse primer for these ehrlichiae and E. platys were designed. By nested PCR with amplification by the universal primers and then reamplification with the specific primers described above, the expected 919-bp product was generated from the blood of the index patient and three additional patients. Blood from these four patients and two more patients with granulocytic morulae contained DNA which was amplified by nested PCR involving a combination of a universal primer and the human granulocytic ehrlichia-E. phagocytophila-E. equi-E. platys group-specific primer. This apparently vector-borne human granulocytic ehrlichia has only 92.5% 16S rDNA homology with E. chaffeensis. Nested PCR with group-specific primers did not amplify E. chaffeensis DNA, and E. chaffeensis-specific primers did not amplify DNAs of the human granulocytic ehrlichia. Thus, six patients were shown to be infected by an Ehrlichia species never previously reported to infect humans.
Comparison of the use of 52Fe and 111In for hemopoietic marrow scanning.

Abstract The results obtained on tests of hemopoietic marrow scanning in experimental animals using 52 Fe(II) citrate and 111 InCl 3 are compared. It was found that while the target/nontarget ratios are higher for the results of the 52 Fe experiments very comparable results can be obtained with 111 In.
The effect of hypoxia on in vitro prevascularization of a thick soft tissue.

Prevascularizing an implantable tissue is one strategy to improve oxygen (O2) transport throughout larger tissues upon implantation. This study examined the role of hypoxia both during (i.e., as a stimulus) and after (i.e., mimicking implant conditions) vascularization of an implantable tissue. Tissues consisted of microcarrier beads coated with human umbilical vein endothelial cells embedded in fibrin. The fibrin was covered with a monolayer of normal human lung fibroblasts (NHLFs), or exposed to conditioned media from NHLFs. Capillary networks developed at 20% or 1% O2 tension for 8 days. In some experiments, tissues were supplemented with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor, whereas in others the tissues prevascularized at 20% O2 were transferred to 1% O2 for 8 additional days. Maximal capillary formation occurred in media conditioned by NHLFs at 20% O2, supplemented with VEGF (concentration >10 pM). Hypoxia (1% O2) did not stimulate basic fibroblast growth fact...
Dendrites of mitral cell neurons contain microtubules of opposite polarity.

Abstract Axonal extensions of neurons show microtubules (MTs) with a uniform polarity indicating that they originate at or near the perikaryon. To obtain information on the polarity of dendritic MTs, a polarity assay was used to examine MTs in dendrites of interneurons (mitral cells) of the olfactory pathway of the bullfrog. The assay involved incubating pieces of olfactory lobe in a tubulin-containing detergent medium which stabilized pre-existing MTs and provided for assembly of exogenous tubulin onto their surfaces as ribbon structures, which appear as ‘hooks’ on the MTs when seen in cross-section. The orientation of the ribbons in a clockwise or anticlockwise direction reflects the polarity of the wall lattice of the MT with which they are associated. Mitral cell dendrites show MTs with ribbons oriented in both directions, indicating two populations of MTs with opposite polarity. The two populations are seen in both the proximal and distal regions of dendrites, and the perikaryon, as expected, shows a mixed population of MTs as regards polarity. It is hypothesized that this is true for most neurons, and that dendritic MTs arise from organizing centers in the dendritic process. If this hypothesis is correct, the polarity of dendritic MTs would depend on the orientation of these centers, which remain to be identified.
Progress and Deficiencies in the Registration of Clinical Trials

In September 2007, President George W. Bush signed into law a bill requiring the registration of clinical trials in phase 2 or beyond and the public reporting of the results of those trials. This article reviews the initial implementation of the law and considers its strengths and weaknesses.
Macular pigment and macular volume in eyes of patients with cystic fibrosis

AbstractBackground. Because patients with cystic fibrosis (CF) are living longer, chronic malabsorption of carotenoids associated with CF resulting in decreased macular pigment (MP) may affect macular long-term health in later-life pathology. This study compared the macular pigment optical density (MPOD) and corresponding central macular volume (MV) of adult CF subjects and age-matched normal controls subjects to determine whether chronic malabsorption associated with CF could adversely affect macular photoreceptor anatomy. Objective. Our aim was to compare MPOD with measurements of central MV in CF patients with age-matched controls. Design. In nine adult CF patients (ages: 29–46) without a history of carotenoid supplementation or known retinal or optic nerve disease MPOD and MV were measured by heterochromatic flicker photometry (HFP) and optical coherence tomography (OCT), respectively, and compared to results obtained from 14 age-matched controls. Results. MPOD was significantly reduced at 15’ and 30’...
Improved efficient field computation via fast Fourier transforms

It is shown that in computing at a set of points regularly distributed over a planar surface the electromagnetic fields radiated by sources similarly distributed over a second plane via the fast Fourier transform (FFT), one need not require that the field and source planes be parallel. This significantly increases the flexibility of such FFT-based algorithms for computational electromagnetics.
A note on dynamics of population with history-dependent birth rate.

A model for the dynamics of a single-species population whose birth rate depends on densities of previous generations is introduced. A difference equation formulation is proposed and the solutions classified for the various parameter values. Data from an experimental population of mice growing in limited space is cited and compared with the model predictions.
Possible Intermediates in Biological Metalloporphyrin Oxidative Degradation. Nickel, Copper, and Cobalt Complexes of Octaethylformybiliverdin and Their Conversion to a Verdoheme

Formylbiliverdin and related chlorophyll-derived molecules are possible products of heme catabolism and other biologically important oxidative processes and are likely to be initially formed as metal complexes. To explore the properties of the formylbiliverdin moiety bound to transition metal ions, complexes of octaethylformylbiliverdin (H2OEFB) with Cu(II), Ni(II), and Co(II) have been prepared, since attempts to prepare an iron complex have produced only an unstable material. Transmetalation of MgII(OEFB), made by photooxidation of MgII(octaethyl-porphyrin), with a metal(II) acetate yields the low-spin complexes: CuII(OEFB), NiII(OEFB), and CoII(OEFB). Single-crystal X-ray diffraction of CuII(OEFB) reveals that it consists of a four-coordinate copper(II) center which is bound to the four nitrogen atoms in distorted planar coordination. The tetrapyrrole ligand has a helical geometry. The structure of the solid is complicated by the existence of three molecules in the asymmetric unit and C−H···O hydrogen...
Transformation of Acetaminophen by Chlorination Produces the Toxicants 1,4-Benzoquinone and N-Acetyl-p-benzoquinone Imine

The reaction of the common pain reliever acetaminophen (paracetamol, 4-acetamidophenol) with hypochlorite was investigated over time under conditions that simulate wastewater disinfection. Initially, the reaction was studied in pure water at neutral pH (7.0), a range of reaction times (2-90 min), and a molar excess of hypochlorite (2-57 times) relative to the acetaminophen concentration. The reaction was monitored using reversed-phase liquid chromatography (LC) with ultraviolet absorbance, electrochemical, and mass spectrometric detection. At 1 micromol/L (150 ppb) and 10 micromol/L (1.5 ppm) levels, acetaminophen readily reacted to form at least 11 discernible products, all of which exhibited greater LC retention than the parent. Two of the products were unequivocally identified as the toxic compounds 1,4-benzoquinone and N-acetyl-p-benzoquinone imine (NAPQI), which is the toxicant associated with lethality in acetaminophen overdoses. With a hypochlorite dose of 57 micromol/L (4 ppm as Cl2), 88% of the acetaminophen (10 micromol/L initial) was transformed in 1 h. The two quinoidal oxidation products 1,4-benzoquinone and NAPQI accounted for 25% and 1.5% of the initial acetaminophen concentration, respectively, at a 1 h reaction time. Other products that were identified included two ring chlorination products, chloro-4-acetamidophenol and dichloro-4-acetamidophenol, which combined were approximately 7% of the initial acetaminophen concentration at 1 h. The reaction was also studied in wastewater, where similar reactivity was noted. These results demonstrate that acetaminophen is likely to be transformed significantly during wastewater chlorination. The reactivity of the chlorine-transformation products was also studied with sulfite to simulate dechlorination, and 1,4-benzoquinone and NAPQI were completely reduced.
A comparison of spray drift predictions to lidar data

Abstract A field trial was conducted to monitor aerially applied pesticide movement above an oak forest in a near-neutral planetary boundary layer using a lidar system. A 36.6-m tower, instrumented at six levels with fast response micrometeorological sensors, recorded wind, turbulence, and temperature profiles during the spray runs. The micrometeorology data was used to drive two spray drift models for a comparison of drift estimates. The models used in this study were USDA Forest Service Cramer-Barry-Grim (FSCBG), an industry standard engineering model, and University of Connecticut Spray Transport (UCST), a heavy particle Lagrangian transport model. Over five spray runs, the FSCBG model predicted
Multiple transmitter neurons in Tritonia. II. Control of gut motility

Two large multiple transmitter neurons are located in each buccal ganglion of Tritonia. One of these neurons (B11) contains large quantities of two neuropeptides and acetylcholine (ACh), whereas the other neuron (B12) appears to contain the same two peptides but no ACh. One of the peptides present in these neurons has recently been sequenced and is termed small cardioactive peptide B (SCPB). Both neurons regulate the motility of the gut. Stimulation of B11 produces a posteriorly directed peristalsis after a short latency. This gut movement may normally accompany swallowing. B11 stimulation also produces an increase in the rate of endogenous contractile activity that is similar to that produced by superfusion of the gut with low concentrations (10(-8) M) of SCPB. Stimulation of B12 produces a vigorous longitudinal contraction of the gut, initiated in the posterior part of the gut and not peristaltic in nature. This movement appears incompatible with swallowing behavior and may be involved in regurgitation.
Distinguishing preterminal and terminal cognitive decline

This paper reviews different methodological approaches taken to examine terminal decline in cognitive function, and presents new findings from the Bronx Aging Study (BAS). Numerous approaches have been taken to assess mortality effects on cognition: comparing survivors and decedents level and rate of change in cognition, and identifying individual differences in cognition associated with time-to-death. However, few studies have actually modeled within-person change in cognition as a function of time-to-death. Using linear mixed models with a change point, intraindividual change in episodic memory was modeled as a function of both age and time-to-death. A dramatic increase in the rate of decline was identified at 8.4 years prior to death, providing clear evidence of a terminal-decline phase that is much longer than previously estimated. These results emphasize the importance of modeling the time course and effects of terminal cognitive decline for understanding cognitive change in aging adults.
Measuring Social Change Preferences in African American Adolescents Development of the Measure of Social Change for Adolescents (MOSC-A)

Studies addressing Black adolescents' social change strategies are nonexistent and might be associated with the absence of social change measures for Black adolescents. In an effort to begin addressing this concern, the 30-item Measure of Social Change for Adolescents (MOSC-A) was designed to measure Black adolescents' first- (i.e., within the system) and second- (outside of the system) order social change strategies. Factor analysis of responses that 226 Black adolescents gave to the MOSC-A revealed first- and second-order social change factors. Item response theory analyses revealed that 65% of the items on the former factor adequately discriminate across different trait levels, but those of the latter were less promising. Scaffolded on this study, future research might refine the MOSC-A's psychometric properties and improve its utility.
Merged CCD/SOI-CMOS technology

In this paper we describe a new technology which fabricates CCDs and fully depleted silicon on insulator CMOS circuits on the same 150-mm silicon wafer. We present results from 7.5 X 7.5-micrometers 2 and 15 X 15-micrometers 2 -pixel imagers that are 512 X 512 frame transfer devices. The 7.5-micrometers -pixel device exhibits a charge handling capacity in excess of 100,000 electrons at 3.3 V and the 15-micrometers - pixel device exhibits a charge-transfer efficiency over 99.998%. In addition, we demonstrate functional SOI CMOS ring oscillators with delay of 47 ps/stage at 3.3 V and 68 ps/stage at 2 V.
The physical base of marine bacterial ecology

Specific affinity theory is compared with traditional ways of understanding the nutrient concentration dependency of microbial growth. It is demonstrated that the Michaelis constant increases with the ratio of metabolic enzyme to membrane permease content of bacteria so that small values can reflect specialization for nutrient collection. When compared to the specific affinity, Kt gives a measure of oligotrophic capacity. Specific affinity, on the other hand, reflects nutrient collection ability directly, and increases with the number of permeases. It can be estimated, along with the other kinetic constant, Vmax, by use of isotopes in natural samples. Because of systematic errors in estimating Vmax, specific affinity is the preferred measure of substrate accumulation ability. The advantage of simultaneous collection of multiple substrates in dilute solution is demonstrated. The structural basis of this advantage is computed from collision frequency and recollision probability, computations that further show that multisubstrate usage is essential for bacterial growth under low-nutrient conditions. Computed growth rates from specific affinities require that several substrates be used simultaneously for growth at measured concentrations. Formulations anticipate that the surface of oligobacteria should be occupied by a diversity of transporter types, that each type of transporter should occupy only a small portion of the cell surface, and the number of cytoplasmic enzymes can be small, allowing small cell size to give a large surface-to-volume ratio for high specific affinity. The large number of substrate types that may be accumulated by a single oligobacterial species is consistent with extensive species diversity.
Management of symptomatic infants with anomalous origin of the left coronary artery from the pulmonary artery

Abstract There is disagreement concerning the optimal management of infants with congestive heart failure due to anomalous origin of the left coronary artery from the pulmonary artery. This report describes treatment in 23 such patients who had congestive heart failure before age 6 months. Eight patients had an operation in the 1st year of life and only two (25 percent) of these patients survived. Fifteen patients received initial medical treatment, and operation was delayed until an average age of 7.5 years; 13 (87 percent) of these patients survived. The two patients who survived early operation are still alive at an average age of 2.5 years. The 13 survivors in the medical group are still alive at an average age of 14.5 years. The age at onset and the severity of congestive heart failure were similar in the two groups. The frequency of the electrocardiographic pattern of myocardial infarction was similar in both groups. The radiographic cardiothoracic ratio was 0.74 in the surgical and 0.66 in the medical group. In 10 patients the left ventricular ejection fraction was less than 20 percent in the 1st year of life. In 7 of these 10 patients operation was performed before age 1 year and 2 (28 percent) survived; of the 3 patients treated medically, 1 (33 percent) survived. The outcome of surgical or medical treatment of the infant with anomalous origin of the left coronary artery from the pulmonary artery may be biased by patient selection. In the infants with depressed left ventricular function, the results of surgical and medical treatment are equally disappointing. Because coronary arterial surgery in the 1st year of life in infants with severely depressed myocardial function has an extremely high mortality rate (75 percent) and because many symptomatic infants with anomalous origin of the left coronary artery from the pulmonary artery can be treated medically and survive, we recommend delay of operative intervention until at least age 18 months.
Application of a capillary gas chromatographic—selected-ion recording mass spectrometric technique to the analysis of diethylstilbestrol and its phosphorylated precursors in plasma and tissues

Abstract A method for the analysis of diethylstilbestrol (DES) which is suitable for pharmacokinetic studies has been developed using capillary gas chromatographic (GC) separation and detection with selected-ion mass spectrometry (MS). This technique has been applied to a variety of samples including human plasma samples and extracts of animal tissues including prostate and liver. To investigate the pharmacokinetics of stilphostrol (diethylstilbestrol diphosphate) we have modified the GC—MS method in two ways. One modification involves a dual assay for DES; the first a direct assay, and the second after hydrolysis of a sample with alkaline phosphatase. The difference in these values is the amount of phosphorylated DES present. The other modification separates stilphostrol and DES using a reversed-phase, ion-paired high-performance liquid chromatographic method followed by alkaline phosphatase hydrolysis followed by the GC—MS method. The details of these three methods are described and some representative data are shown.
The Decrease in FlaA Observed in a flaB Mutant of Borrelia burgdorferi Occurs Posttranscriptionally

The Lyme disease bacterium Borrelia burgdorferi is a motile spirochete with a flat-wave morphology. The periplasmic flagella, which are situated between the outer membrane sheath and cell cylinder, are essential for both the cell's wavy shape and motility. Here we focus on the structure and regulation of its periplasmic flagella. Previous studies have suggested that the periplasmic flagella consist of a polymer of the major filament protein FlaB and a minor protein, FlaA. We used immunoprecipitation methodology to present further evidence that FlaA is indeed a flagellar protein. In addition, in contrast to FlaA of the spirochete Brachyspira hyodysenteriae, B. burgdorferi FlaA did not impact the overall helical shape of the periplasmic flagella. We have previously shown that B. burgdorferi lacks the sigma factor-dependent cascade control of motility gene transcription found in other bacteria. To begin to understand motility gene regulation in B. burgdorferi, we examined the effects of an insertion mutation in flaB on the amounts of proteins encoded by motility genes. Of several motility gene-encoded proteins examined, only the amount of FlaA was decreased in the flaB mutant; it was 13% compared to the wild-type amount. Real-time reverse transcriptase PCR analysis indicated that this inhibition was not the result of a decrease in flaA mRNA. In addition, protein stability analysis suggested that FlaA was turned over in the flaB mutant. Our results indicate that the lack of FlaB negatively influences the amount of FlaA found in the cell and that this effect is at the level of either translational control or protein turnover.
REDISTRIBUTIVE TAXATION WITHOUT EXCESS BURDEN

Redistributive taxation imposes no excess burden when: (a) the taxed group behaves collusively and takes into account government behavior, and (b) the redistribution outcome is an interior solution (i.e., after redistribution the government values a marginal dollar of income to each class equally). There is no dynamic inconsistency in capital taxation under the same conditions.
Harvest and Sale of Baitfish in Wyoming

Abstract The 1986 harvest and sale of baitfish in Wyoming were assessed through a mail survey of licensed personal-use collectors and through interviews with retail dealers. A 95% return by personal-use collectors indicated that 233 collectors harvested 156,000 baitfish. Interviews with 58 of 65 (89%) licensed dealers indicated that they sold 671,000 baitfish, at least 82% of which were collected from the wild in Wyoming waters. Retail value of sales was $92,000, which is relatively small compared to sales in other states. Size of this industry is restricted by a low human population and by regulations–primarily the ban on interbasin transportation of live fish–that limit both wholesale and retail supplies of baitfish.
Learner-controlled practice difficulty in the training of a complex task: Cognitive and motivational mechanisms.

An inherent aspect of learner-controlled instructional environments is the ability of learners to affect the degree of difficulty faced during training. However, research has yet to examine how learner-controlled practice difficulty affects learning. Based on the notion of desirable difficulties (Bjork, 1994), this study examined the cognitive and motivational antecedents and outcomes of learner-controlled practice difficulty in relation to learning a complex task. Using a complex videogame involving both strong cognitive and psychomotor demands, 112 young adult males were given control over their practice difficulty, which was reflected in the complexity of the training task. Results show that general mental ability, prior experience, pre-training self-efficacy, and error encouragement were positively related to learner-controlled practice difficulty. In turn, practice difficulty was directly related to task knowledge and post-training performance, and it was related to adaptive performance through the mediating influences of task knowledge and post-training performance. In general, this study supports the notion that training difficulty operationalized in terms of task complexity is positively related to both knowledge and performance outcomes. Results are discussed with respect to the need for more research examining how task complexity and other forms of difficulty could be leveraged to advance learner-controlled instructional practices.
ERα suppresses slug expression directly by transcriptional repression

Two of the most common signalling pathways in breast cancer are the ER (oestrogen receptor) ligand activation pathway and the E-cadherin snai1 slug EMT (epithelial–mesenchymal transition) pathway. Although these pathways have been thought to interact indirectly, the present study is the first to observe direct interactions between these pathways that involves the regulation of slug expression. Specifically we report that ligand-activated ERα suppressed slug expression directly by repression of transcription and that knockdown of ERα with RNA interference increased slug expression. More specifically, slug expression was down-regulated in ERα-negative MDA-MB-468 cells transfected with ERα after treatment with E2 (17β-oestradiol). The down-regulation of slug in the ERα-positive MCF-7 cell line was mediated by direct repression of slug transcription by the formation of a co-repressor complex involving ligand-activated ERα protein, HDAC1 (histone deacetylase 1) and N-CoR (nuclear receptor co-repressor). This finding was confirmed by sequential ChIP (chromatin immunoprecipitation) studies. In the MCF-7 cell line, slug expression normally was low. In addition, knockdown of ERα with RNA interference in this cell line increased slug expression. This effect could be partially reversed by treatment of the cells with E2. The efficacy of the effect of ERα on slug repression was dependent on the overall level of ERα. These observations confirmed that slug was an E2-responsive gene.
Clearance (née Rowland) concepts: a downdate and an update

A number of experimental observations in the late 1960s, early 1970s could not be explained by the pharmacokinetic theory available at that time. For example rats receiving phenobarbital as an enzyme inducing agent exhibited increased elimination of phenylbutazone in vitro in liver microsomes and in vivo in whole animals compared to that observed in non-induced animals. However, for desipramine, although phenobarbital increased elimination in microsomes, no change in plasma disappearance was noted in vivo for this drug between rats induced with phenobarbital and control rats. Similar in vitro–in vivo discordancies were seen with changes in protein binding. The introduction of clearance concepts in the early 1970s by Professor Rowland and others provided the scientific rationale for these apparently contradictory findings and the recognition that clearance, not half-life, was the measure of the body’s ability to eliminate drugs and most importantly that changes in pathology and physiology could be correlated with measures of clearance. Up to that time half-life was well recognized in terms of basic chemical principles as an appropriate measure of the rate of elimination and reflective of changes in the rate of elimination. The difference between chemistry and pharmacokinetics, however, is that in chemistry the volume in which the reaction occurs does not change. In contrast, in pharmacokinetics, disease states and differences in physiology can change the space available in which the drug may distribute in the body. Thus, it was necessary to develop a pharmacokinetic measure of volume that was independent of elimination, i.e., Vss. Now, the relationship between Vss and clearance led to a unique measure of time of drug in the body, the mean residence time. Although this parameter is calculated in all PK programs, very few pharmaceutical scientists know how it can be useful. Very recently, we have shown that the concepts of accumulation, prediction of which is the clinically relevant use for half-life and mean residence time, are flawed and that the appropriate time dependent parameter to predict accumulation has not been previously correctly identified. Finally, when clearance concepts were developed our understanding of the importance of drug transporters was nonexistent. A critical, and generally unrecognized assumption (which is only explicitly stated in Professor Rowland’s seminal 1973 paper), in the development of the theory of clearance is that the unbound drug concentration in the organ of elimination is in a constant equilibrium with the unbound drug concentration in the systemic circulation, where drug concentration measurements are made. Transporter drug–drug and disease interactions may, in fact, change this equilibrium and potentially what we consider as intrinsic clearance, may not be independent of an eliminating organ volume parameter, contrary to what we have been teaching for the past 37 years.
Intermediale Grenzgänge: Technologie, Sprache und Musik in Georges Perecs Hörspiel Die Maschine

Georges Perec’s experimental German radio-play from 1968 is one of the most radical attempts to construct a literary text that is in close affinity to rhetorical and musical compositional techniques. Based upon Goethe’s poem “Wandrers Nachtlied II,” the text is both a linguistic and semantic analysis and a playful re-creation of the poem. Transmitted by radio, but staged as a preprogrammed computational simulation that replaces the alphabetic code with the algorithmic one of the computer, the play reconstructs the historical transition from symbolic through analog to digital media. Focusing on the materiality of language, Perec’s poetic de-composition and re-composition of Goethe’s original lead to numerous new variations that follow strict, predetermined rules. Even though Perec neither creates a musical work nor transposes a musical composition into literature, he nevertheless succeeds in producing a polyphonic, acoustic artwork that transcends the intermedial boundaries between the two distinct semiotic systems of music and language.
Genetic resistance factor for HIV-1 and immune response to varicella zoster virus.

Summary A 32 bp deletion in the chemokine receptor CCR5 gene modulates HIV-1 infection. However, whether this CCR5 gene variation modifies immunity to common herpesvirus infections is unknown. We investigated whole blood IgG concentrations of 157 normal adult blood donors. Also we assessed whether the 32 bp deletion of CCR5 (Δ32 CCR5 ) was associated with circulating IgG to four herpesviruses: varicella zoster virus, Epstein-Barr virus, cytomegalovirus, and herpes simplex virus type 1 and type 2. Individuals who carried Δ32 CCR5 were 9·2 times more likely to be seronegative for varicella zoster virus than non-carriers (95% CI 2·9–29·1), but no differences were seen for the other herpesviruses studied. Variation in CCR5 may modulate humoral immunity to varicella zoster virus.