cssi/SciSciGPT-SciSciNet huggingface dataset:
Vps54 regulates Drosophila neuromuscular junction development and controls postsynaptic density composition via a Rab7-dependent mechanism

ABSTRACT Vps54 is a subunit of the Golgi-associated retrograde protein (GARP) complex, which is involved in tethering endosome-derived vesicles to the trans-Golgi network (TGN). In the wobbler mouse, a model for human motor neuron (MN) disease, reduction in the levels of Vps54 causes neurodegeneration. However, it is unclear how disruption of GARP-mediated vesicle transport leads to MN dysfunction and ultimately neurodegeneration. To better understand the role of Vps54 in MNs, we have disrupted expression of the Vps54 ortholog in Drosophila and examined the impact on the larval neuromuscular junction (NMJ). Here, we show that both null mutants and MN-specific knockdown of Vps54 leads to NMJ overgrowth. Reduction of Vps54 partially disrupts localization of the t-SNARE, Syntaxin-16, to the TGN but has no impact on endosomal pools. Presynaptic knockdown of Vps54 in MNs combined with overexpression of the small GTPases Rab5, Rab7, or Rab11 suppresses the Vps54 NMJ phenotype. Conversely, knockdown of Vps54 combined with overexpression of dominant negative Rab7 causes axonal and behavioral abnormalities including a decrease in postysynaptic Dlg and GluRIIB levels without any effect on GluRIIA. Taken together, these data suggest that Vps54 controls larval MN axon development and postsynaptic density composition by modulating Rab7-mediated endosomal trafficking.
On the Collapse of Shallow Elastic Membranes

Publisher Summary This chapter focuses on the collapse of shallow elastic membranes. The nonlinear theory of buckling of elastic shells is presented in the chapter to study the response of the shell as Q0 increases by using the membrane as a model, where Q0 is a parameter proportional to the total pressure force acting on the membrane. It was reasoned that as the stiffness of the shell increased the response curve of the membrane was continuously deformed. Furthermore, the membrane theory is more susceptible to mathematical analysis than the corresponding shell theory because the membrane differential equations are of lower order. Any tensile solution of the membrane problem is the leading term in the asymptotic expansion of the solution of the corresponding shell problem. The chapter presents a preliminary report of a numerical study of the collapse of shallow membranes subjected to external pressure. For a specified shape and a specified pressure, the boundary value problem is solved by using the shooting method.
A requirement for an active proton delivery network supports a compound I-mediated C-C bond cleavage in CYP51 catalysis.

CYP51 enzymes (sterol 14α-demethylases) are cytochromes P450 that catalyze multistep reactions. The CYP51 reaction occurs in all biological kingdoms and is essential in sterol biosynthesis. It removes the 14α-methyl group from cyclized sterol precursors by first forming an alcohol, then an aldehyde, and finally eliminating formic acid with the introduction of a Δ14–15 double bond in the sterol core. The first two steps are typical hydroxylations, mediated by an electrophilic compound I mechanism. The third step, C–C bond cleavage, has been proposed to involve either compound I (i.e. FeO3+) or, alternatively, a proton transfer-independent nucleophilic ferric peroxo anion (compound 0, i.e. Fe3+O2–). Here, using comparative crystallographic and biochemical analyses of WT human CYP51 (CYP51A1) and its D231A/H314A mutant, whose proton delivery network is destroyed (as evidenced in a 1.98-A X-ray structure in complex with lanosterol), we demonstrate that deformylation of the 14α-carboxaldehyde intermediate requires an active proton relay network to drive the catalysis. These results indicate a unified, compound I-based mechanism for all three steps of the CYP51 reaction, as previously established for CYP11A1 and CYP19A1. We anticipate that our approach can be applied to mechanistic studies of other P450s that catalyze multistep reactions, such as C–C bond cleavage.
Embedded Video Questions as a Low-Stakes Assignment during the Remote Learning Transition.

During the transition from an in-person Organic Chemistry II class to a remote learning version of the class midsemester, a small-group problem-solving session exercise was replaced with embedded video questions as a low-stakes assignment with direct instructor feedback. Whereas the in-person small-group problem-solving session was a group submission, the embedded video questions were an individual submission. The benefits of this change included direct feedback for each student, which was proposed to assist all students, in contrast with the problem-solving sessions, which may have excluded students not fully participating in that particular social setting. Additionally, this was a way to engage each student directly during a period of social isolation. Costs include substantial time investment from the instructor and a narrower selection of problems for the students to view, as well as a lack of academic community building.
3D Printing of a self-healing, high strength, and reprocessable thermoset

Direct ink writing (DIW) is a 3D printing technique that can fabricate user-defined thermoset objects via ink extrusion and solidification. Here we demonstrate the development of a novel ink for DIW that can be used for the fabrication of a high strength, self-healing thermoset. The ink exhibits a tensile strength of 77 MPa after cure, which is comparable to that of engineering-grade epoxies. The low viscosity of the ink effectively eliminates voids between the deposited filaments, thus achieving isotropic mechanical properties of the printed thermoset. The thermally reversible Diels–Alder (DA) reaction between furan and maleimide allows the reversible formation of DA cross-links in the polymer and a high recovery (∼85%) of polymer strength after the first occurrence of damage. Repeatable healing is achieved for the thermoset without a significant decrease in healing performance after three damage-healing cycles. The isotropic characteristic leads to little deterioration in the healing performance of the thermoset printed in different directions, compared with that of the molded ones. Finally, unlike most thermosetting materials, the developed thermoset is reprocessable and can be remolded. This work shows the potential for 3D printing thermosets composed of furan/maleimide monomers to produce strong, self-healing, and recyclable 3D printed materials.
Embodied Discrimination and “Mutilated Historicity”: Archiving Black Women’s Bodies in the Huntington Collection

The concept of structural violence has been applied to bioarchaeological investigations to consider how inequality comes to be embodied in various social contexts by taking into account paleopathological analyses; the treatment of bodies, including their burial or curation; and various postmortem interventions such as dissection. In conjunction with a structural violence framework, I draw on the work of historian Marisa Fuentes to consider violence within archives. Fuentes (Dispossessed Lives: Enslaved Women, Violence, and the Archive 2016: 16) introduces the concept of “mutilated historicity,” or “the violent condition in which enslaved women appear in the archive disfigured and violated.” Violence committed on bodies permeates the material record; here I consider the many forms such violence can take, including within historical accounts. At the same time, I also conceive of the archive more broadly and more insightful when “the body in the archive” and “the material body” are integrated. I extend this concept while studying the disarticulated and incomplete physical and archival remains of black women who died in post-emancipation New York City and whose skeletal bodies are now curated as part of the Huntington Collection.
Cash Flow, Consumption Risk, and the Cross‐section of Stock Returns

I link an asset's risk premium to two characteristics of its underlying cash flow: covariance and duration. Using empirically novel estimates of both cash flow characteristics based exclusively on accounting earnings and aggregate consumption data, I examine their dynamic interaction in a two-factor cash flow model and find that they are able to explain up to 82% of the cross-sectional variation in the average returns on size, book-to-market, and long-term reversal-sorted portfolios for the period 1964 to 2002. This finding highlights the importance of fundamental cash flow characteristics in determining the risk exposure of an asset.
ASR mitigation using binary and ternary blends with waste glass powder

Abstract Alkali silica reaction (ASR), commonly referred to as “concrete cancer”, is a major durability problem in concrete structures. ASR is a chemical reaction that occurs between the reactive amorphous silica from the natural aggregates and the alkalis in cement in the presence of moisture. This reaction causes undue expansion and cracks in hardened concrete which over time results in deterioration. The use of supplementary cementitious materials (SCMs) has been proven effective to minimize ASR distress. In this study, a synergistic function of glass powder was evaluated in binary and ternary blends with conventional SCMs (slag and silica fume) for ASR mitigation. The ASR mitigation was evaluated using the accelerated mortar bar test (AMBT) and miniature concrete prism test (MCPT) methods. Additional testing including the flow test, strength activity index (SAI), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy-dispersive x-ray spectral analysis (EDS) was conducted to examine the pozzolanic activity, microstructural analysis, and chemical composition. The results demonstrated that the use of SCMs along with glass powder reduce ASR expansion substantially. The binary or ternary blends of 20% replacement of glass powder, slag, or silica fume can be utilized for ASR mitigation without compromising other concrete properties. Also, the ternary system containing glass powder with other conventional SCMs performed better compared to individual use of SCMs to mitigate ASR. These results were also supported by the findings of the microstructure and chemical analysis, in which the glass powder and SCMs were found to reduce the cracks due to ASR expansion.
Building entrepreneurship research for impact: Scope, phenomenon, and translation

This editorial sets out to suggest how academics can enhance the impact of their work. I hope this will be useful for authors submitting to the Journal of Small Business Management (JSBM) as well a...
Connecting families to food resources amid the covid-19 pandemic: A cross-sectional survey of early care and education providers in two U.S. States

Early care and education (ECE) settings are important avenues for reaching young children and their families with food and nutrition resources, including through the U.S. federally funded Child and Adult Care Food Program (CACFP). Researchers conducted a cross-sectional survey of ECE providers in two U.S. states in November 2020 to identify approaches used to connect families with food and nutrition resources amid the COVID-19 pandemic. Logistic regression models were used to estimate odds of sites reporting no approaches and adjusted Poisson models were used to estimate the incidence rate ratio of the mean number of approaches, comparing sites that participate in CACFP to those that did not. A total of 589 ECE sites provided responses. Of those, 43% (n = 255) participated in CACFP. CACFP participating sites were more likely to report using any approaches to connecting families to food resources and significantly more likely to report offering “grab and go” meals, providing meal delivery, distributing food boxes to families, and recommending community food resources than non-CACFP sites. This study suggests that CACFP sites may have greater capacity to connect families to food resources amid emergencies than non-CACFP participating sites.
Building a reactive immune system for software services

We propose a reactive approach for handling a wide variety of software failures, ranging from remotely exploitable vulnerabilities to more mundane bugs that cause abnormal program termination (e.g., illegal memory dereference) or other recognizable bad behavior (e.g., computational denial of service). Our emphasis is in creating "self-healing" software that can protect itself against a recurring fault until a more comprehensive fix is applied. Briefly, our system monitors an application during its execution using a variety of external software probes, trying to localize (in terms of code regions) observed faults. In future runs of the application, the "faulty" region of code will be executed by an instruction-level emulator. The emulator will check for recurrences of previously seen faults before each instruction is executed. When a fault is detected, we recover program execution to a safe control flow. Using the emulator for small pieces of code, as directed by the observed failure, allows us to minimize the performance impact on the immunized application. We discuss the overall system architecture and a prototype implementation for the x86 platform. We show the effectiveness of our approach against a range of attacks and other software failures in real applications such as Apache, sshd, and Bind. Our preliminary performance evaluation shows that although full emulation can be prohibitively expensive, selective emulation can incur as little as 30% performance overhead relative to an uninstrumented (but failure-prone) instance of Apache. Although this overhead is significant, we believe our work is a promising first step in developing self-healing software.
Space-Time Kriging of Groundwater Data

A large number of geohydrological variables may be viewed as realizations of spatiotemporal random functions. In many instances, the available data are composed of long time series, located at few scattered points. To analyse such data sets it seems imperative to expand the available geostatistical techniques into the time-space domain. It is assumed that the spatial and the temporal components of the data can be characterized by intrinsic random functions. The space-time kriging is then applied to groundwater quantity data in southern Georgia. It appears that this procedure yields maps with lower estimation variances, while allowing forecasting and hindcasting.
Secure computation of hidden Markov models

Hidden Markov Model (HMM) is a popular statistical tool with a large number of applications in pattern recognition. In some of such applications, including speaker recognition in particular, the computation involves personal data that can identify individuals and must be protected. For that reason, we develop privacy-preserving techniques for HMM and Gaussian mixture model (GMM) computation suitable for use in speaker recognition and other applications. Unlike prior work, our solution uses floating point arithmetic, which allows us to simultaneously achieve high accuracy, provable security guarantees, and reasonable performance. We develop techniques for both two-party HMM and GMM computation based on threshold homomorphic encryption and multi-party computation based on threshold linear secret sharing, which are suitable for secure collaborative computation as well as secure outsourcing.
Isolation of a Bacterial Membrane Protein, Nectin, Essential for the Attachment of Adenosine Triphosphatase

Abstract We have isolated from Streptococcus faecalis plasma membranes a new protein, termed nectin, which is required for the attachment of the membrane enzyme, ATPase. Both nectin and membrane-bound ATPase are released from the native membranes by a procedure, described previously, which depends on repeated washing in dilute buffer without Mg++. Resolution of the solubilized nectin and ATPase can then be accomplished by gel filtration through agarose. The ATPase, separated from nectin by passage through agarose, fails to reattach to enzyme-depleted membranes unless nectin is added. The amount of ATPase that recombines with the depleted membranes is proportional to the amount of nectin added until the membrane receptor sites for the enzyme become nearly saturated. Nectin is heat labile and has an ultraviolet absorption spectrum typical of a protein. By the method of gel filtration through Sephadex, we estimate that its molecular weight is 37,000.
Siting Federico Barocci and the Renaissance Aesthetic

Focusing on what he calls 'the performative gaze', the author explores the artistic world of the Urbino painter Federico Barocci (1535-1612) in the context of Renaissance culture. Through analysis ...
AACN Synergy Model for Patient Care Case Study of a CHF Patient

within the walls of the hospital setting. Today’s healthcare environment mandates that patients with serious diseases live in their homes, causing the need for acute and critical care settings to reach out to their patients not only to assist them in maintaining a quality of life but also to decrease costs of hospital readmissions. This situation is especially true for patients with chronic heart failure (CHF). In the United States, many patients with CHF regularly visit CHF clinics that are run by advanced practice nurses; these clinics assist patients with maintaining and often improving their state of heart failure, while also proving cost-effective. The Synergy Model provides the framework for nurses to manage complex clients experiencing acute exasperation of their illness and to work toward reducing the trajectory of the illness. The purpose of this article is to discuss the application of The Synergy Model to an ambulatory CHF clinic. We will discuss the characteristics of a patient who visited a local clinic, with the advanced practice nurse holding a Authors
The sertoli cell cytoskeleton: A target for toxicant-induced germ cell loss

Numerous studies in recent years have elucidated fundamental properties of axoplasmic structure, biochemistry, and function. The structural role of the cytoskeletal elements, the orientation of MTs within the axon, the phenomenon of MT-dependent transport, and the identity and direction of movement of two MT motors--kinesin and MAP-1C--have been revealed. For many years to come, researchers investigating the structure and function of the Sertoli cell cytoskeleton will be able to adapt techniques gleaned from work on the axonal cytoskeleton. Innovative thinking will be required to apply these techniques to the special circumstances of the male reproductive system; however, the underlying questions are similar. For example, knowledge of several fundamental properties of transport processes in the Sertoli cell would facilitate the toxicologic evaluation of this system. What is the orientation of MTs within the Sertoli cell cytoplasm? Are the fast-growing (+) ends of all MTs in the Sertoli cell cytoplasm directed toward the lumen? This is an important question because the direction of MT-dependent transport involving known MT motors is dependent upon the MT orientation. Which of the Sertoli cell transport pathways are MT-dependent pathways? What are the MT motors involved in these pathways? Ultrastructural examination following exposure to specific cytoskeleton-disrupting agents has highlighted the importance of AFs, IFs, and MTs in the Sertoli cell. Future research will focus on the nature of those molecules which integrate these cytoskeletal components into a dynamic whole, the regulatory systems which control this integration, and the role of an integrated cytoskeleton in Sertoli cell function and testicular homeostasis. Toxicology will be an active participant in this process of scientific discovery. The selective nervous system and testicular toxicants may be useful tools in revealing similarities in the cytoskeletal organization of these apparently disparate organ systems. By searching for common targets in the testis and nervous system, the mechanisms of action of these agents may be more easily, and more confidently, determined.
A longitudinal study of visual function in carriers of X-linked recessive retinitis pigmentosa

Abstract Objective This study was carried out to evaluate the progression of visual function impairment in carriers of X-linked recessive retinitis pigmentosa. We also assessed the relationship between the retinal findings at presentation and the extent of deterioration. Design Observational, retrospective, case series. Participants Twenty-seven carriers of X-linked recessive retinitis pigmentosa. Methods Each carrier was clinically categorized into one of four grades (grades 0 through 3) depending on the presence or absence of a tapetal-like retinal reflex and the extent of peripheral pigmentary degeneration. A complete ophthalmologic examination was performed and data for visual acuity, visual field area, and electroretinographic measurements were collected on the most recent visit in both eyes. These were then compared with similar data obtained on their initial visits. Main outcome measures A comparison of visual function was carried out between the initial visit and the most recent visit on each carrier. The visual acuity was measured with Snellen's acuity charts. The visual fields to targets V-4-e and II-4-e were planimeterized and used for the analysis. The electroretinographic (ERG) measures used were light-adapted single-flash b-wave amplitudes and 30-Hz red flicker for cone function, dark-adapted maximal b-wave amplitudes, and response to a low intensity blue-flash for rod function. Results None of the 11 carriers with a tapetal-like reflex only (grade 1) showed any significant change in visual acuity or fields as compared with 3 of 7 (43%) carriers with diffuse peripheral pigmentary findings (grade 3) who showed significant deterioration in visual acuity in at least one eye, and 6 of 7 (86%) who showed a significant decrease in visual field area with at least one target size in at least one eye. By comparison, only 1 of 10 carriers with a grade 1 fundus finding demonstrated a significant decrease in maximal dark-adapted ERG function as compared with 5 of 6 (83%) carriers with grade 3 in response to a single-flash stimulus and with 4 of 5 (80%) carriers in response to a single-flash blue stimulus. For the single-flash photopic response, none of the 10 carriers with grade 1 showed any significant deterioration, whereas 2 of 4 (50%) with grade 3 did show such deterioration. The ERG responses for carriers with grade 2 were in between the extent of decrease in ERG amplitudes of those in carriers with grades 1 and 3. Conclusions In our cohort of X-linked retinitis pigmentosa carriers, those with only a tapetal-like retinal reflex at presentation had a better prognosis to retain visual function than those with peripheral retinal pigmentation. These data are useful in counseling such carriers as to their visual prognosis.
Protein and lactate dehydrogenase levels in Aedes aegypti

Lactate dehydrogenase (LDH) and total protein concentrations of adult female Aedes aegypti were determined following emergence from the pupal cuticle through a period of 20 days, during which time 2 blood meals were taken. Preceding the blood meal, LDH exhibited distinct peaks 5 and 10 days following emergence. LDH activity remained constant for 2 hr following a blood meal, then rose rapidly to a value 10 times pre-blood meal values 7 hr after feeding. This activity then steadily declined to reach pre-blood meal values within 72 hr. This pattern was repeated in mosquitoes given a second blood meal as well as in virgin mosquitoes taking blood, suggesting that the blood meal stimulates either the synthesis or activation of LDH.
A study of the energy aspects of aqueous dynamics, I

Abstract By the use of an appropriate theoretical model, an approximation of that kinetic energy in the eye arising solely from the work put into the eye in the form of affective bulk flow has been made. This approximation is T ∼ 8 × 10 −8 erg. This value has been compared to the total net rate of work input so as to arrive at a graphic view of the nature of the flow in the eye. We see that the flow with which we are concerned can be likened to the flow in a most fine-gauge hypodermic needle or, if you like, to the flow of a very viscous grease in a pipe of moderate size, where essentially all of the work input is expended against viscosity and dissipated as heat. In the eye this heat loss occurs probably at the trabecular meshwork where frictional factors or resistance R are concentrated.
Guidance and Control, for Small AUVs Using DGPS and Doppler Aided Inertial Underwater Navigation

Abstract : This paper provides an overview of the Naval Postgraduate School ARIES autonomous underwater vehicle and its guidance, navigation and control performance. An attempt is made to highlight its' current operational capabilities and provide a description of future enhancements for greater mission utility and flexibility. An overview of the vehicle design along with descriptions of all major hardware components and sensors is given. A major discussion of the implementation of a modular, multi-rate, multi-process software architecture for ARIES autonomous control is provided. The architecture is designed to operate using either a single computer processor or two independent, cooperating processors linked through a network interface for improved load balancing. A dual computer implementation is presented here since each processor assumes different tasks for mission operation. Also included is a section on the underwater navigation method using a real-time extended Kalman filter that fuses all sensor data and computes the real time position, orientation, velocity, etc., of the vehicle. Experimental results for navigational accuracy using a DGPS / IMU / Doppler aided navigation system are presented with DGPS pop-up maneuvers.
Adhesion-associated and PKC-modulated changes in serine/threonine phosphorylation of p120-catenin.

p120-catenin (p120) was originally identified as a tyrosine kinase substrate, and subsequently shown to regulate cadherin-mediated cell−cell adhesion. Binding of the p120 Arm domain to E-cadherin a...
Identification of kaempferol-3-rhamnoglucoside and quercetin-3-glucoglucoside in cottonseed

The flavonol glycosides, quercetin-3-glucoglucoside and kaempferol-3-rhamnoglucoside, have been separated from crushed, delinted cottonseed (kernel and hull) by extensive use of paper chromatography, ultraviolet spectrophotometry, and qualitative and quantitative analysis of their hydrolysis products. Details of the separation and identification are described.
Dynamic imaging of cerebellar Purkinje cells reveals a population of filopodia which cross-link dendrites during early postnatal development.

Two-photon microscopy was used to image dye-loaded filopodia of Purkinje cells in acute rat cerebellar slices. In the process of examining filopodia in Purkinje cells from a period of rapid dendritic growth (P10-21), we observed a small subset of filopodia which appeared to form connections between two dendrites of the same cell, usually between the tips of two adjacent dendrites or the tip of a dendrite and the shaft of another. There were fewer of these ‘filopodial bridges’ present at P18-21 than at an earlier stage in development (P10-12) and they were absent in mature Purkinje cells. Filopodial bridges do not appear to be an artifact of living brain slice preparation as they may also be seen by dye-loading Purkinje cells in slices prepared from perfusion-fixed brain. They have varied morphologies which are mostly similar to conventional, unattached filopodia. However, when measured over tens of minutes, filopodial bridges were observed to be less motile than conventional filopodia as indicated by a reduced index of expansion. While the functions of these novel structures are unknown it is attractive to speculate that they play an instructive role in Purkinje cell dendritic development
Impersonal probability as an ideal assessment based on accessible evidence: A viable construct?

When risk analysts and others refer to the “true” probability of an event, it is not easy to give it a meaning which is sound and useful as a communication device for regulatory, research planning, and related purposes. An interpretation is herein offered which, unlike Bayesian probability, is impersonal and does not depend on a particular assessor; unlike Carnap's “logical” probability, it does not depend on information actually to hand. It is a generalization of frequency and propensity interpretations of impersonal probability applicable to unique events: an ideal assessment based on currently accessible (not in general “perfect”) evidence. The argument is illustrated from decision-aiding experience which motivated the enquiry.
Comprehensive summary of the Institute for Human and Machine Cognition's experience with LittleDog

We discuss the main issues and challenges with quadrupedal locomotion over rough terrain in the context of the Defense Advanced Research Projects Agencyâs Learning Locomotion program. We present our controller for the LittleDog platform, which allows for continuous transition between a static crawl gait and a dynamic trot gait depending on the roughness of the terrain. We provide detailed descriptions for some of our key algorithm components, such as a fast footstep planner for rough terrain, a body pose finder for a given support polygon, and a new type of parameterized gait. We present the results of our algorithm, which proved successful in the program, crossing all 10 terrain boards on the final test at an average speed of 11.2 cm/s. We conclude with a discussion on the applicability of this work for platforms other than LittleDog and in environments other than the Learning Locomotion designed tests.
In-use measurement of the activity, fuel use, and emissions of front-loader refuse trucks

Abstract Field measurements were made for six front-loader refuse trucks for over 560 miles (901 km) and 47 h of operation using a portable emissions measurement system, electronic control unit data logger, and global positioning system receivers. Daily activity, fuel use rates, and emission rates are quantified in terms of operating mode bins defined by the U.S. Environmental Protection Agency for the MOVES emission factor model. On average, 44 (±4) percent of time was spent at idle, 5 (±1) percent braking or decelerating, 11 (±2) percent coasting, 23 (±3) percent cruising or accelerating at low speed (up to 25 mph, 40.2 kmph), 10 (±2) percent cruising or accelerating at moderate speed (25–50 mph, 40.2 to 80.4 kmph), and 7 (±3) percent cruising or accelerating at high speed (50 mph, 80.4 kmph or higher). Fuel use and emission rates varied among operating modes by factors of 6–24. The estimated daily activity cycle average fuel economy ranges from 2.3 to 3.2 mpg (0.98–1.4 kmpl). The PM emission rates for trucks with diesel particulate filters are 98 percent lower compared to those without. Variation in truck weight lead to differences in average fuel use and emission rates of 20 percent or less, except for hydrocarbons. The variation in the empirically-based daily activity cycle average rates were highly correlated with MOVES estimates, except for hydrocarbons. The data collected here are useful for quantifying daily activity specific to front-loaders, and for developing fuel use and emission estimates and models for this type of vehicle.
The distribution and regulation of aromatase activity in the central nervous system

Our data demonstrate that androgen-dependent AA is found in areas of the brain that are essential for the neuroendocrine control of gonadotropin secretion and sexual behavior. However, until we know more about the neurons that contain AA, e.g., whether they are peptidergic or catecholaminergic, we can not speculate about the neuronal functions that depend on local estrogen formation. In fact, the association of AA with neurons and not glia has only recently been demonstrated. That estrogens and androgens synergize in the regulation of various neuroendocrine functions has been known for many years, but an explanation of the synergism at the cellular level was not available. One explanation for this synergism may lie in our recent observation that the administration of exogenous estradiol to castrated rats increases androgen-receptor concentrations in specific brain nuclei. Perhaps locally formed estrogens work in a similar fashion to regulate androgen receptors in the brain of the intact male.
Reconstructing the formation and land use history of the Mound 2 depression at Río Viejo, Oaxaca, Mexico

Archaeological and geoarchaeological work in the lower Rio Verde Valley, Oaxaca, Mexico reveal a varied spatial relationship between the prehistoric inhabitants and this dynamic floodplain region over the last 3000 years. Significant demographic expansion occurred by the Late Formative period following floodplain aggradation resulting from a change in stream hydrology and morphology. During the Classic and Postclassic periods, major shifts in settlement and land use occurred, primarily from the productive floodplain to the piedmont. The archaeological site of Rio Viejo has played a pivotal role in the political and social history of the valley. Archaeological data indicate the site was occupied from the Middle Formative to the Early Postclassic and was an urban center and the political seat of the region during the Terminal Formative and again in the Late Classic. Four large depressions are associated with mounded architecture at the site. We collected paleoenvironmental and geoarchaeological data from the Mound 2 feature. A synthesis of this multi-proxy data has enhanced our understanding of site formation, occupation, and land use from the Late Formative to Postclassic times. The analysis indicates that the depression associated with Mound 2 was originally a borrow pit on the floodplain that was enhanced and augmented by monumental mound building. The area around Mound 2 was the focus of domestic and agricultural use during the Terminal Formative. An apparent cessation of activity around Mound 2 occurred during the Early Classic, which is consistent with a significant contraction in population at the site at this time. Activity resumed at Mound 2 in the Late Classic and continued until at least the Early Postclassic. These changes in occupation history appear to have resulted from political developments within the valley.
Examination of yeast cell parameters using light diffusion

Cell parameters such as size and density may provide crucial information on issues such as aging and cancer. Measurement of these parameters in bulk, in a cells natural environment are therefore important. For bulk samples light diffusion measurements using transmission spatial profiles and correlation function analysis provide information on the mean free path, absorption and refractive index. Speckle fractal analysis can also provide cell structure information. For cells in suspension forward scattering is used to provide size information via the Mie theory for spherical objects. Two types of live yeast cells were measured in bulk and in suspension at various densities. The bulk samples were compacted by centrifuge into fractions whose mass and volume was measured. The parameter values obtained by optical diffusion were used to infer the density and size variations. The measurement detected density variation of about 10% for yeast grown under normal conditions. The size variation is also about 10% but it contained more uncertainty due to the constant density assumption used in the Mie theory for spherical objects. High resolution optical microscopy confirmed the cell size and showed that it followed a lognormal distribution. The density variation resulted mainly from size differences with a smaller contribution from mass structure such as protein. The results indicate that diffusion measurement is consistent with density measurement and could possibly be used as a cell density probe in clinical applications.
The role of radiotherapy in the treatment of soft tissue sarcoma: a retrospective study 1958–73

Survival and local control data are presented for a series of 109 cases of soft tissue sarcoma treated 1958–73. A five-year minimum follow-up period is available. The two-year and five-year survival rates for the complete series are respectively 80 and 68%. In a comparison of survival results for different histological subgroups we found a 94% two-year survival for liposarcomas compared with 80% for fibrosarcomas and 74% for synovial sarcomas; and five-year survivals of 73, 68 and 51% respectively. Sixty-two per cent of the series achieved local control of the disease after initial treatment, and this figure increased to 83% after further treatment. Eighty-six per cent of tumours of the extremities (66/77) were controlled locally without amputation. Of those in the complete series whose disease recurred, either locally or distantly, 50% experienced this recurrence within one year of initial treatment. In only 7% did the recurrence occur more than five years after initial treatment. These results are encouraging and we conclude that they justify an initial treatment policy of conservative surgery combined with radical radiotherapy.
Single Unpaired Nucleotides Facilitate HIV-1 Reverse Transcriptase Displacement Synthesis through Duplex RNA

During reverse transcription of viral RNA, HIV-1 reverse transcriptase (RT) encounters RNA stem-loop structures that require displacement synthesis activity in which RT disrupts the RNA helix to access the template strand. A primer extension assay was developed to assess HIV-1 RT RNA displacement synthesis activity in vitro. Initial results revealed that HIV-1 RT performs only limited amounts of RNA displacement through long stretches of RNA duplex, with the majority of synthesis stalling at sequence-dependent pause positions. DNA displacement synthesis through the same sequence, however, proceeded rapidly to the end of the template. The RNA folding algorithm mfold indicated that the presence of an unpaired nucleotide, or "bulge," along the RNA duplex would promote helix melting ahead of the DNA primer terminus to create a small gap of nondisplacement synthesis. Primer extension assays using substrates possessing single-nucleotide bulges in the nontemplate strand near pause sites resulted in diminished pausing at positions within the predicted melted region. Surprisingly, the bulges also reduced pausing distal to the bulge at positions that are expected to remain base-paired. Further analysis revealed that stalling during RNA displacement synthesis results from the displaced RNA re-annealing to the template strand thus forcing the primer terminus to become unpaired and, therefore, not extendable. Introduction of a bulge facilitates displacement synthesis through distal regions by increasing RT processivity in the vicinity of a bulge and reducing the impact of branch migration on primer extension.
Localization of Crystals in Diseased Oats Treated with Uranyl Acetate

Uranyl acetate, a suppressor of victorin-induced electrolyte leakage in oat leaves when applied together with, or before, victorin, also suppressed victorin-induced changes in ultra-structure. Uranyl crystallized in cell walls and near the plasmalemma of vascular cells, but was excluded from the protoplasm. Fewer crystals occurred near the plasmalemma when leaves were allowed to take up uranyl and victorin simultaneously than when uranyl alone was absorbed, but deposition in cell walls was similar in the two treatments. No differences in crystal distribution were found in uranyl-treated leaves which subsequently took up either water or victorin. The most striking effect of prolonged exposure to uranyl was increased vesicular activity in the protoplasm, formation of complex concentric membranes, and tonoplast damage. Following victorin treatment, uranyl post-treatment was ineffective in suppressing electrolyte leakage or preserving normal cellular ultrastructure. More severe ultrastructural damage was found in victorintreated leaves after uranyl post-treatments than after post-treatment with water, a result of victorin-induced damage which facilitates uranyl entry into the protoplasm.
Information organization and retrieval using a topic maps-based ontology: Results of a task-based evaluation

As information becomes richer and more complex, alternative information-organization methods are needed to more effectively and efficiently retrieve information from various systems, including the Web. The objective of this study is to explore how a Topic Maps-based ontology approach affects users' searching performance. Forty participants participated in a task-based evaluation where two dependent variables, recall and search time, were measured. The results of this study indicate that a Topic Maps-based ontology information retrieval (TOIR) system has a significant and positive effect on both recall and search time, compared to a thesaurus-based information retrieval (TIR) system. These results suggest that the inclusion of a Topic Maps-based ontology is a beneficial approach to take when designing information retrieval systems. © 2008 Wiley Periodicals, Inc.
Complex Activity Recognition Using Granger Constrained DBN (GCDBN) in Sports and Surveillance Video

Modeling interactions of multiple co-occurring objects in a complex activity is becoming increasingly popular in the video domain. The Dynamic Bayesian Network (DBN) has been applied to this problem in the past due to its natural ability to statistically capture complex temporal dependencies. However, standard DBN structure learning algorithms are generatively learned, require manual structure definitions, and/or are computationally complex or restrictive. We propose a novel structure learning solution that fuses the Granger Causality statistic, a direct measure of temporal dependence, with the Adaboost feature selection algorithm to automatically constrain the temporal links of a DBN in a discriminative manner. This approach enables us to completely define the DBN structure prior to parameter learning, which reduces computational complexity in addition to providing a more descriptive structure. We refer to this modeling approach as the Granger Constraints DBN (GCDBN). Our experiments show how the GCDBN outperforms two of the most relevant state-of-the-art graphical models in complex activity classification on handball video data, surveillance data, and synthetic data.
Intertrial stimuli and differentiation of the conditioned eyelid response

One hundred thirty-six human Ss participated in two differential eyelid conditioning experiments designed to demonstrate the inhibitory properties of intertriai stimuli. In Experiment I when the intertriai stimulus was a tone (IT) lying midway between CS+ and CS− on the auditory frequency dimension differentiation was enhanced compared with a group which received only noise during the ITI, but this enhancement occurred only when CS+ and CS− were highly similar tones. In Experiment II differentiation was poorer where the order of stimuli along the frequency dimension was IT, CS+, CS− compared with IT, CS−, CS+.
Absorption of 14C-2-hydroxy-4-(methylthio)butanoic acid (Alimet) from the hindgut of the broiler chick.

Abstract The purpose of these studies was to examine the role of the hindgut of the broiler chick in the absorption of 2-hydroxy-4-(methylthio)butanoic acid (HMB). When 14 C-HMB was delivered directly into the hindgut, the rate of absorption from this gastrointestinal site was about 40% of the administered dose per hour. Plasma radiolabel appearance indicated that the 14 C-HMB lost from the hindgut was being absorbed into the bloodstream of the bird. Decarboxylation experiments using cecal microorganisms showed that the loss of 14 C-HMB could not be accounted for by bacterial metabolism. When birds were dosed with radiolabeled HMB and tissue samples were tested, results showed that the 14 C-HMB that was absorbed from the hindgut was incorporated into protein in a dose-related manner. In addition, an equimolar, equal specific activity intraperitoneal dose of HMB did not alter the rate of HMB absorption from the hindgut. This indicates that HMB absorption from the gut is not limited by HMB already in the body tissues. This result confirmed that the rate of HMB diffusion into the blood and its conversion to methionine in body tissues were sufficient to maintain the concentration gradient required for the continued absorption of HMB. Finally, whole body autoradiography comparing 35 S-HMB and 35 S-DL-methionine showed no substantial differences in terms of label density or distribution. These studies demonstrate that 14 C-HMB disappears from the lumen of the large intestine and ceca when it is administered directly into the hindgut. This research confirms that HMB is absorbed throughout the entire gastrointestinal system.
Effect of a Dithiol on Survival Time after Irradiation

CONTRARY to previous reports1, Doherty et al. 2 obtained partial protection of X-irradiated mice with 2,3-dimercaptopropanol. If a foreign dithiol compound is effective perhaps the dithiol form of an essential metabolite might also prove beneficial in radiation injury. Mice were exposed to 550 r. acute whole body X-irradiation under our usual conditions3. The animals received 50 mgm./kgm. of DL-6,8-dithioloctanoic acid, the reduced form of thioctic acid, according to the schedule in Table 1. It is evident that the compound significantly increased the ST50 day, particularly if administered prior to irradiation. However, it has no real effect in reducing total mortality. The mechanisms involved in such partial protection are obscure, but dithiols are known to form resonance-stabilized radicals which could interact with the various oxidizing radicals produced by ionizing radiation. Such reactions could be continuous until the dithiol was completely destroyed. If the proportion of dithiol to oxidizeis was in favour of the latter, this could explain the increased ST50 day and the unaffected total mortality observed in the group receiving the dithiol immediately prior to irradiation. Pre-irradiation medication could also result in protection of radiosensitive groups in the tissues by direct combination, but it might be difficult to obtain complete coverage. Post-irradiation medication could assist in breaking the chain reaction involving organic peroxides5 but still not prevent the early damage which would tend to decrease total survival. Thus it would appear that a dithiol can increase survival time, possibly by the above mechanisms, yet give no permanent protection against the lethal effects of ionizing radiation.
Susceptibility of some marine phytoplankton species to cell breakage during filtration and post-filtration rinsing

Abstract Several fragile phytoplankton species among a diverse group of 13 species were found to be very susceptible to cell breakage when exposed to the air under vacuum between the filtration and rinsing steps used to terminate 14C fixation experiments and remove residual [ 14 C]HCO 3 − . Up to 60% of fixed carbon after 15-min incubation was found in the rinse. Losses were even greater when cultures were pulsed with NH 4 + at the start of the incubation, probably because rapid NH 4 + uptake leads to the accumulation of large pool of soluble and low molecular weight compounds. Most likely, the cells, when exposed to the air, are subject to extreme osmotic shock and rupture. Unaccountable losses of 14 C occurred with polycarbonate filiters relative to glass-fiber filters. In addition, vacuum pressure differentials >25–100 mmHg across polycarbonate filters also caused cell breakage that led to the accumulation of 14 C in the filtrate. Avoiding air exposure of the filter between the filtration and rinsing steps or eliminating the rinsing step entirely and acid-soaking or fuming the filters led to virtually complete recovery of fixed carbon. Our results based on 15-min incubations may not be directly comparable with longer-term incubations, but they do serve highlight our concerns about filtration procedures in general.