cssi/SciSciGPT-SciSciNet huggingface dataset:
Authority and accountability in light of disciplinary practices in science

Abstract Our aim is to explicate the importance of students’ learning about disciplinary authority and accountability and to anchor our analysis in transcripts from a North American high school biology classroom. Previous analyses of the entire two-day lesson and a qualitative description of an episode from one day showed that the students were able to see errors in their peers’ proposals better than they were able to point out the potential errors in their own. Our findings led us to at least one conclusion that differs from earlier formulations of productive disciplinary engagement: that the interpersonal process of construction and critique precedes and fosters its intrapersonal appropriation. The implications for a practice theory of learning are discussed.
Educational Renaissance: A Student's Viewpoint

To the Editor. With the profession of pharmacy expanding exponentially and pharmacists taking on more extensive roles that require the use of problem-solving and critical-thinking skills, the necessity for reshaping the way classroom content is delivered will become paramount to the success of both the profession and colleges and schools of pharmacy graduating future pharmacists. The recommended tenets of an initiative such as this have been well articulated previously1; therefore, my intent is to elucidate, from a student's viewpoint, the philosophical need for such an educational renaissance.
Nu 445 in the treatment of urinary infections due to Gram negative bacilli.

Summary1. An in vitro study of the action of Nu 445 shows that this drug occasionally exerts a greater bacteriostatic and bactericidal effect on certain strains of gram negative bacilli than do other sulfonamides.2. Clinical trial in 20 patients with urinary infections indicated excellent effectiveness of the drug in uncomplicated, monovalent infections due to E. coll or B. proteus.3. Results of treatment in polyvalent infections and in cases with complicating pathology were poor.4. The marked lack of toxicity of Nu 445 recommends its use in appropriate cases, in which it will occasionally be found to be more effective than other sulfonamides.
Osmic staining of amphibian and gastropod photoreceptors.

Eyes of two species of amphibian tadpoles (Xenopus laevis and Hyla regilla) and of a pulmonate snail (Helix aspersa) were impregnated with osmium tetroxide, with or without extraction by chloroform. Amphibian rods, but not cones, stained heavily with aqueous osmium tetroxide. After extraction with chloroform, osmification (OsO4 in CCl4) did not produce heavy deposits of osmium black, but 30–45 diameter granules in the outer leaflets of rod disk membranes became visible. The granules may be stained molecules of photopigment. The pigmented epithelium of light-adapted eyes, but not of dark-adapted eyes, exhibited prominent Golgi cisternae and cytoplasmic vesicles filled with reaction product. Photosensory cells of H. aspersa exhibited osmium black in rhabdomeric microvilli and in 800 vesicles, termed photic vesicles. After extraction with chloroform, little reaction product appeared, but 30–50 diameter granules, interpreted as stained molecules of photopigment, were found in the vesicles and microvilli.
Targeting autophagy in breast cancer

Macroautophagy (referred to as autophagy here) is an intracellular degradation pathway enhanced in response to a variety of stresses and in response to nutrient deprivation. This process provides the cell with nutrients and energy by degrading aggregated and damaged proteins as well as compromised organelles. Since autophagy has been linked to diverse diseases including cancer, it has recently become a very interesting target in breast cancer treatment. Indeed, current clinical trials are trying to use chloroquine or hydroxychloroquine, alone or in combination with other drugs to inhibit autophagy during breast cancer therapy since chemotherapy and radiation, regimens that are used to treat breast cancer, are known to induce autophagy in cancer cells. Importantly, in breast cancer, autophagy has been involved in the development of resistance to chemotherapy and to anti-estrogens. Moreover, a close relationship has recently been described between autophagy and the HER2 receptor. Here, we discuss some of the recent findings relating autophagy and cancer with a particular focus on breast cancer therapy.
Amendments for the in situ remediation of contaminated sediments: Evaluation of potential environmental impacts

Active sediment caps represent a comparatively new technology for remediating contaminated sediments. They are made by applying chemically active amendments that reduce contaminant mobility and bioavailability to the sediment surface. The objective of this study was to determine if active cap amendments including organoclay, apatite, and biopolymers have the potential to harm benthic organisms. Methods included laboratory bioassays of amendment toxicity and field evaluations of amendment impacts on organisms held in cages placed within pilot-scale active caps located in Steel Creek, a South Carolina (USA) stream. Test organisms included Hyalella azteca, Leptocheirus plumulosus, Lumbriculus variegatus, and Corbicula fluminea to represent a range of feeding modes, burrowing behaviors, and both fresh and saltwater organisms. In addition to the laboratory and field assays, chemical extractions were performed to determine if the amendments contained harmful impurities that could leach into the ambient environment. Laboratory bioassays indicated that 100% apatite had minimal effects on Hyalella in freshwater and up to 25% organoclay was nontoxic to Leptocheirus in brackish water. Field evaluations indicated that pilot-scale caps composed of up to 50% apatite and 25% organoclay did not harm Hyalella, Lumbriculus, or Corbicula. In contrast, organisms in caps containing biopolymers died because of physical entrapment and/or suffocation by the viscous biopolymers. The extractions showed that the amendments did not release harmful concentrations of metals. These studies indicated that apatite and organoclay are nontoxic at concentrations (up to 50% and 25% by weight, respectively) needed for the construction of active caps that are useful for the remediation of metals and organic contaminants in sediments.
Freeze fracture analysis of muscle plasma membrane in bupivacaine HCl-induced degeneration and regeneration

We did freeze fracture analysis of bupivacaine HCl-induced muscle fiber damage. The muscle plasma membrane in rat extensor digitorum longus and soleus muscle was analyzed for the density of orthogonal arrays and caveolae at periods of five minutes to 60 days after application of the myotoxin. In degenerating muscle a decrease in the density of caveolae was observed. In regenerating extensor digitorum longus muscle, a decrease in the density of orthogonal arrays and an increase in the density of caveolae was present. The results show that freeze fracture alterations in fast twitch regenerating muscle are similar to those seen in the muscles of patients with Duchenne muscular dystrophy.
Parametric studies in industrial distillation: Part II. Heuristic optimization

The venture cost of operating a single distillation tower is examined as a function of the overhead operating pressure, the feed fractional vaporization, and the vapor to minimum vapor rate ratio. One variable is changed parametrically, while the two remaining are fixed at their optimal values. The percentage increase in cost above the minimum is shown. The relative significance of each variable is discussed. A method is presented for estimating the optimal overhead operating pressure of a distillation tower. Simplified methods for calculating relative tower costs are evaluated. These methods utilize estimates of the Underwood minimum vapor rate, the Fenske minimum theoretical stages, and the temperature drop up the tower, or combinations thereof. Consideration of the economic interactions between two towers in a train is also important in the evaluation of alternatives. It is often necessary to neglect any interactions which may occur in order to synthesize highly integrated systems. A study of these interactions between towers in the direct and inverted configurations is presented. Observed interactions between towers in complex design configurations are also discussed.
Propulsion efficiency and cost of transport for copepods: a hydromechanical model of crustacean swimming

In the absence of direct measurement, costs of locomotion to small swimming Crustacea ( 3. Net cost of transport was intermediate to the values found experimentally for fish and larger crustaceans. This was a consequence of the predicted mechanical efficiency (34%) of the copepod's paddle propulsion, and of increased parasitic resistance resulting from non-steady velocity swimming.
Calculation of molecular ionization potentials: Comparison of MSXα and ESCA

Preliminary results of calculations by means of the ms Xα (multiple-scattering Xα) method on four small molecules (N2, CO, NO, CF4) are presented. Comparisons with the molecular ionization potentials measured by the esca (electron spectroscopy for chemical analysis) experiments show in general better agreement than the semiempirical calculations and about the same agreement as the ab initio scf calculations.
Abstract: Cascaded TCP: BIG Throughput for BIG DATA Applications in Distributed HPC

Saturating high capacity and high latency paths is a challenge with vanilla TCP implementations. This is primarily due to congestion-control algorithms which adapt window sizes when acknowledgements are received. With large latencies, the congestion-control algorithms have to wait longer to respond to network conditions (e.g., congestion), and thus result in less aggregate throughput. We argue that throughput can be improved if we reduce the impact of large end-to-end latencies by introducing layer-4 relays along the path. Such relays would enable a cascade of TCP connections, each with lower latency, resulting in better aggregate throughput. This would directly benefit typical applications as well as BIG DATA applications in distributed HPC. We present empirical results supporting our hypothesis.
Getting Information Systems to Interact: The Social Fact Character of “Object” Clarity as a Factor in Designing Information Systems

This article considers challenges to getting information systems to recognize “objects” in other information systems. We explore a tension between commitment to standardization and the constitutive and situated social fact requirements of human comprehension and work through an ethnographic study of an information system design team meeting.2 Facilitating interoperability between systems is an important challenge currently facing design teams. Our study elucidates—in the design team's own words—problems that design teams confront with “object” and “concept” certainty, practical “use” and “language”: with defining what they call a “What” when data objects must cross boundaries. The refrain “What is the ‘What’?” punctuates the meeting. Although human use and comprehension frame their concerns, they treat meaning, practical use, and language as “technical” and “philosophical” issues. The social issues they acknowledge are confined to “governance.” Given their reliance on performed social objects, including “role” and “identity”, at key points in their discussion, however, and the importance of “language” and “concepts” to their concerns, we point out social dimensions of their task, suggesting that a broader understanding of the importance of constitutive practices and their situated character in achieving information objects—and social objects more generally—could change the team's perception of their options.
Fitting the Single-System Design to Family Treatment

Applications of single-system designs (SSDs) in work with families have usually been confined to behavioral forms of intervention, to specific target problems, single family subsystems, and to academic research undertakings. There is need for designs that can encompass systems-based family approaches, a range of family variables, multiple family subsystems, and the realities of agency practice. Such designs might make use of retrospective and "natural" multiple baselines, standardized instruments, qualitative methods, multiple tracking of family-systems variables, and recent developments in change process research. These methodological possibilities are discussed, along with how SSDs can be used to evaluate family treatment modules and in programs of developmental research. Illustrations are provided from a project supervised by the author.
Seismic tomography of compressional wave attenuation structure for Kı̄lauea Volcano, Hawai‘i

We present a frequency-independent three-dimensional (3-D) compressional wave attenuation model (indicated by the reciprocal of quality factor Qp) for Kilauea Volcano in Hawai‘i. We apply the simul2000 tomographic algorithm to the attenuation operator t* values for the inversion of Qp perturbations through a recent 3-D seismic velocity model and earthquake location catalog. The t* values are measured from amplitude spectra of 26708 P wave arrivals of 1036 events recorded by 61 seismic stations at the Hawaiian Volcanology Observatory. The 3-D Qp model has a uniform horizontal grid spacing of 3 km, and the vertical node intervals range between 2 and 10 km down to 35 km depth. In general, the resolved Qp values increase with depth, and there is a correlation between seismic activity and low-Qp values. The area beneath the summit caldera is dominated by low-Qp anomalies throughout the entire resolved depth range. The Southwest Rift Zone and the East Rift Zone exhibit very high Qp values at about 9 km depth, whereas the shallow depths are characterized with low-Qp anomalies comparable with those in the summit area. The seismic zones and fault systems generally display relatively high Qp values relative to the summit. The newly developed Qp model provides an important complement to the existing velocity models for exploring the magmatic system and evaluating and interpreting intrinsic physical properties of the rocks in the study area.
High Temperature Thermal Analysis of Graphite and Silicon Carbide with Millimeter-Wave Radiometry

Millimeter-wave thermal analysis instrumentation is being developed for characterization of high temperature materials required for diverse fuel and structural needs in extreme high temperature reactor environments. A two-receiver 137 GHz system with orthogonal polarizations for anisotropic properties resolution has been implemented at MIT and is being tested with graphite and silicon carbide specimens at temperatures up to 1300oC. Real time measurement sensitivity to submillimeter surface displacement and simulated anisotropic surface emissivity is demonstrated.
The Limits and Possibilities of Educational Change

(1981). The Limits and Possibilities of Educational Change. The Review of Education: Vol. 7, No. 2, pp. 175-182.
Freer markets and the abatement of carbon emissions: the electricity-generating sector in India

This paper develops a framework to explore the implications of trade and domestic policy distortions for the magnitude of carbon emissions and for the welfare costs of abating these emissions. An application to the electricity-generating sector in India shows that economic policy reforms can also be effective environmental policy instruments and reduce carbon emissions even in the absence of an emissions tax. This reduction in emissions is accompanied by an increase in domestic welfare, an increase in electricity output, and conservation of coal. Coordinating trade and domestic policy reform with an emissions tax policy reduces emissions further, while leading to gains in welfare that are greater than those under an emissions tax policy alone.
Carp haemoglobin iron-imidazole linkage and subunit equivalence; evidence from resonance Raman spectroscopy of deoxy- and nitrosyl forms

Nitrosyl hemoglobin (Hb) from carp shows a resonance Raman spectrum characteristic of 6-coordinate (NO) heme. Switching the quaternary structure from R to T by addition of insitol hexaphosphate (IHP) at pH 5.8 does not produce a 5-coordinate spectrum, as it does for human Hb. Only intensity changes are seen for bands at ∼490, 387 and 357 cm−1, indicating a subtle alteration in the porphyrin-protein interaction. In carp deoxy Hb, IHP addition produced a shift of the Fe-ImH (ImH = imidazole) stretching mode, from 223 to 214 cm−1. The band remained symmetrical, indicating essential equivalence of the subunits. This is in contrast to human deoxy Hb for which the R-T shift in the Fe-ImH frequency is much greater in the α than the β chains. In carp Hb all the Fe-ImH bonds appear to be weakened in the T state, but to an extent insufficient to induce rupture upon binding NO.
Managing somatization: medically unexplained should not mean medically ignored.

Physical symptoms are the most common reason patients seek medical attention. Despite medical advances, up to a third remain unexplained, even after extensive evaluation.1 Fortunately, most patients with medically unexplained symptoms experience symptom resolution,2 although a subset of patients' symptoms persists. The number, severity, and functional impact of patient symptoms likely represents a continuum from the small proportion of patients meeting DSM-IV criteria for somatization disorder to the many patients with persistent symptoms who do not have somatization disorder but nonetheless have considerable impairment. Previously, management of such patients was reactive rather than proactive, and largely based on limiting care. Clinicians negotiated and tried to optimize visit frequency and limit diagnostic testing and referrals for stable symptoms. Symptoms were treated symptomatically, usually with limited success. Both clinicians and patients were frustrated by this process and patients often left to seek other “better” advice.
Learning about Politics From The Daily Show: The Role of Viewer Orientation and Processing Motivations

Although late-night comedy and satirical news programs like The Daily Show have been recognized as important sources of political information, prior research suggests that viewers gain only a limited amount of political knowledge from watching these programs. Drawing from uses and gratification theory and extant research on political information processing, this study examines whether learning from The Daily Show depends on whether viewers orient to the message as news or as entertainment. Results from an online experiment suggest that viewers who orient to a segment from The Daily Show as news or as a mix of news and entertainment invest more mental effort and subsequently learn more than viewers who have a purely entertainment orientation. Further, among viewers with a purely entertainment orientation, providing them with an explicit informational-processing goal increases the amount of mental effort and learning relative to viewers who are given no explicit viewing objective.
Improving acoustic fall recognition by adaptive signal windowing

Each year more than a third of elderly fall in the United States. To address this problem we are developing an acoustic fall detection system based on a microphone array. The main task of the acoustic system is to detect all the falls that occur in an indoor environment while producing as few as possible false alarms. One of the challenges of this task is to accurately locate where the fall signal comes from so that beamforming can be applied to improve the recognition of fall signals. In this paper we describe a simple fall signal location procedure that proved effective in preliminary testing.
Synthesis and CO2 sorption properties of pure and modified lithium zirconate

Abstract Optimum conditions for synthesis of lithium zirconate by the solid state reaction were studied experimentally. The monoclinic phase lithium zirconate can be formed from a lithium carbonate, zirconia and potassium carbonate mixture of a certain composition in the temperature range of 850–1200 °C. The equilibrium and kinetics of CO2 sorption on pure lithium zirconate, potassium doped lithium zirconate and potassium doped lithium yttrium-zirconate were studied experimentally by TGA and modeled by gas–solid reaction equilibrium and a simple diffusion model based on the double shell CO2 sorption mechanism. Both experimental results and thermodynamics analysis show a step function for the isotherms of CO2 sorption on these materials. The rate of the CO2 sorption on pure lithium zirconate is controlled by the diffusion of CO2 in the solid lithium carbonate shell. For potassium doped lithium zirconate or lithium yttrium-zirconate the rate limiting step for CO2 sorption is shifted to diffusion of oxygen ions in the zirconia shell.
Adaptive Two-Scale Nonlinear Homogenization

An adaptive two-scale homogenization procedure combining a reduced order and a direct mathematical homogenization method is developed. A simple strain-based indicator is used to guide the construction of a nearly optimal model consisting of either a direct or a reduced order unit cell model. Consistent interscale transfer operators are developed to map the information between the two homogenization models. Verification and validation studies are conducted on a composites plate with a center crack, metal-polyurea sandwich plate, and fabric composites circular tube.
Equilibration of weakly nonlinear salt fingers

An analytical model is developed to explain the equilibration mechanism of the salt finger instability in unbounded temperature and salinity gradients. The theory is based on the weakly nonlinear asymptotic expansion about the point of marginal instability. The proposed solutions attribute equilibration of salt fingers to a combination of two processes: (i) the triad interaction and (ii) spontaneous development of the mean vertical shear. The non-resonant triad interactions control the equilibration of linear growth for moderate and large values of Prandtl number (Pr) and for slightly unstable parameters. For small Pr and/or rigorous instabilities, the mean shear effects become essential. It is shown that, individually, neither the mean field nor the triad interaction models can accurately describe the equilibrium patterns of salt fingers in all regions of the parameter space. Therefore, we propose a new hybrid model, which represents both stabilizing effects in a single framework. The resulting solutions agree with the fully nonlinear numerical simulations over a wide range of governing parameters.
A practical precoding approach for radar/communications spectrum sharing

In this paper, we consider spectrum sharing between multiple-input multiple-output (MIMO) radar system and a communication system modeled as MIMO interference channel. We derive a zero-forcing precoder for radar transmitter which completely eliminates the radar interference to communication users. Obtaining the precoder requires the knowledge of an effective interference channel matrix composed of the channel matrices to all of the communication receivers and the postprocessing matrices employed by them. We propose a channel estimation phase in which all of the communication receivers coordinate in their choice of training symbols and power transmission and the radar transmitter can estimate the effective interference channel. We investigate the effect of radar precoder and channel estimation error on the performance of radar and interference to communication receivers. Our results indicate that while the precoder null steers the radar interference to communication users it degrades the radar performance by introducing correlation to the probing signals. We show that this performance loss can be compensated for by increasing the number of radar antennas.
The ecological crisis and the work ethic

Some writers have indicted capitalism and Christianity as the sources of our environmental disruption. Yet, both capitalism and socialism share the maximization of profit, productivity and the use of power to serve the interests and goals of the technostructure. Environmental crises are found in both capitalistic and socialistic countries where rapid industrialization has proceeded without consideration for social costs. In addition, it appears more likely that man's failure to unite science and ethics in a manner to guide, restrain and control individual and collective behavior in relation to the real world is more causative of environmental disruption than the tenets of Christianity alone. A new ethic of man is needed in which the quality of life and survival supersedes the importance of the products of work.
Virtual Surface Temperature Sensor for Multi-zone Commercial Buildings☆

Abstract Multi-zone structure is commonly used in small commercial office buildings, retail stores and supermarket. While there is no adjacent partition wall between the zones, the impact of a neighbor zone on the current zone can be approximated and analyzed through the application of virtual walls. It is critical to accurately estimate the virtual wall surface temperature in order to evaluate the model uncertainty and apply improved supervisory control on multiple rooftop air-conditioning units (RTUs). We propose an innovative virtual surface temperature sensor based on system-identification to solve this challenge. The validation of the virtual temperature model is processed by the three validation criteria: goodness of fit (G), mean squared error (MSE) and coefficient of determination (R2) through off-control conditions with data obtained from a building simulation platform. Further, the sensitivity analysis using the on-control three conditions (under-sizing, properly sizing and oversizing condition) is conducted for analyzing and evaluating the performance of this system-identification based virtual sensor.
The Photosynthetic Response of Alaskan Tundra Plants to Increased Season Length and Soil Warming

ABSTRACT How the carbon balance of arctic ecosystems responds to climate warming will depend on the changes in carbon assimilation capacity of tundra plant species. Along with air and soil warming, one of the consequences of warming likely to be important for carbon assimilation of tundra plant species is an expected 40% increase in growing season length. We examined the effects of a lengthened growing season and soil warming on the photosynthetic capacity of seven tundra plant species from four growth forms that comprise >90% of the vascular cover of wet tussock tundra. Maximum photosynthetic capacity of these key species was relatively unchanged by the manipulation that significantly altered growing season length, active layer depth, and soil temperatures. Highest photosynthetic rates were found for the forb, Polygonum bistorta, and the lowest for dwarf evergreen shrubs. Seasonal patterns revealed that plants maintained relatively high light-saturated photosynthetic capacity (Amax) values throughout mos...
A novel dual‐frequency dual‐polarized stacked patch microstrip array feed for remote sensing reflector antennas

This paper presents the design and implementation of a dual-frequency dual-linear polarized stacked patch array feed with a novel probe-feeding architecture for future spaceborne synthetic aperture radar (SAR) applications. To facilitate measurements of soil moisture from space, a large aperture antenna of 30 m operating in VHF (137.5 MHz) and UHF (435 MHz) frequencies is desirable. An array feed that synthesizes a rectangular effective aperture on the 30-m reflector is proposed in order to obtain matched beams at the VHF and UHF frequencies. We focus on the layout, design, and prototype performance of the stacked-patch microstrip array designed for scaled operating frequencies of 1.13 GHz (lower patch) and 3.57 GHz (upper patch). The study is also aimed at analyzing the performance of the array in combination with a 3.65-m reflector. Our test results demonstrate a good correlation between the measurements and simulations from finite-difference time domain (FDTD) and reflector analysis codes, thus validating the design for use in SAR for soil-moisture applications. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1250–1258, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21669
Toward a more perfect society

I have touched on the following points: perpetuation of the spirit of DDW, membership expansion, innovation in our annual meeting, greater membership input, fertilization of the bed-bench breeding ground, support from industry, establishment of a research foundation, strategic planning for our journal, and the setting of standards. I have also asked some questions: Do we want more uniform standards of practice? Do we insist on a more rigorous evaluation of technology? How lofty a standard do we wish to achieve? Are we asking the right clinical questions? We must actively participate in and contribute to the future of surgery of the alimentary tract so that we are indeed among the best. All of us are proud to be members of the SSAT. Now and in the future we can state with progressively greater pride that we are members of the best surgical organization devoted to the alimentary tract because we swim harder and we are becoming the lead dogs!
Isolated central hypothyroidism in short stature

Mild hypothyroidism can be difficult to diagnose, particularly when it is caused by deficiency of TSH or TSH-releasing hormone (TRH). Such central hypothyroidism occurs most often in association with growth hormone deficiency (GHD). Isolated central hypothyroidism has been considered rare. The TSH surge test is the most sensitive test currently available for confirming the diagnosis. Results are abnormal in many cases where response to TRH is normal. Short children referred between 1986 and 1994 for evaluation (n = 235, 74 girls; height 2 or more SD below mean for age; no history of radiation therapy) were selected for study. TSH samples were obtained hourly for study of TSH surge (1400-1800 h and 2200-0400 h). Growth hormone (GH) samples were obtained every 20 min (2000-0800 h). GH stimulation tests included arginine, insulin, and L-dopa. Thirty-nine children were found to have GHD (peak GH < or = 7 micrograms/L) and 15 had mild primary hypothyroidism (TSH 5-15 mU/L). Of the remaining 181 children with apparent idiopathic short stature (ISS), 30 had a blunted TSH surge. All 30 had free thyroxine (FT4) in the lowest third of the normal range, consistent with values seen in documented central hypothyroidism. They were 13% of the total group, 16% of the ISS children, and 32% of the ISS children with FT4 in the lowest third of normal. (In comparison, diagnosis of GHD was made in 16% of the total group.) In conclusion, use of a direct FT4 assay to screen short children for possible subtle hypothyroidism (along with other appropriate testing) identifies a subgroup with a one in three possibility of an easily treated cause--isolated central hypothyroidism.
Strongyloides myopotomi: fine structure of the body wall and alimentary tract of the adult and third-stage larva.

Abstract The body wall of the adult and larval worms is composed of cuticle, hypodermis, and muscle layers. The cortex layer of the adult has an outer unit membrane; cortex and matrix layers are both amorphous. The matrix contains regularly spaced transverse bands surrounded by bundles of collagen fibers. The fiber layer consists of two rows of large collagen-like fibers and an outer layer of smaller unbanded fibers. In third-stage larvae the fiber layer is granular and the inner portion of the matrix is crystalloid. Nerves lie between the plasma membrane of the larval hypodermis and the sarcolemma of the muscle cells, which are similar in larvae and adults. Muscle structure resembles that of known nematode species. The striated border of the adult intestinal cells is composed of many microvilli, clothed in an extracellular tubular coat. The terminal web, directly beneath the apical plasma membrane, contains extensions of the cytoplasmic cores of the microvilli. Intestinal cells are separated by a terminal bar and contain pigment granules, dense foamy masses, endoplasmic reticulum, mitochondria, lipid, and a large nucleus. The larval intestine has widely spaced microvilli with dense central cores. A granular extracellular coat surrounding the microvilli may serve as a food reserve for the larva. The larval esophagus is a triradiate, cellular structure lined with cuticle. Posteriorly, the three esophageal glands contain many laminated secretory granules. The larval hindgut is also lined with cuticle and its cells contain vacuoles with membranous elements.
Efficacy of suicide gene therapy in hypoxic rat 9L glioma cells

Viral vector mediated suicide gene therapy (SGT) involving thymidine kinase (TK) or cytosine deaminase (CD) have considerable promise in the treatment of malignant brain tumors. An unresolved issue is to what extent tumor hypoxia influences the outcome of SGT since brain tumors characterized by regions of hypoxia have potentially reduced cellular metabolism and SGT’s cytotoxicity is manifest through cellular metabolism. We studied in vitro and in vivo, the effect of hypoxia on the cytotoxicity of SGT in rat 9L glioma cells. Neither acute nor chronic hypoxia affected the cell killing of SGT by TK or CD. In vivo confirmation that SGT efficacy was not adversely affected by tumor hypoxia using the hypoxic cell marker pimonidazole was shown by the absence of a change in tumor hypoxia by SGT. These studies support the use of SGT utilizing either TK or CD gene strategies even when tumors are characterized by a hypoxic microenvironment.
Rural Public Transportation: Perceptions of Transit Managers, Directors of Area Agencies on Aging, and Elders

Transit systems in rural areas help elders maintain contact with social services, conduct business, and visit friends. Surveys of transit managers, area agency on aging (AAA) directors, and rural elders age 75 and over in Iowa were conducted in 1993 to determine if these groups believed that there isunmet need for transita mongrural elders and to assess the groups' perceptions of transit service. Transit managers and AAA directors did believe that such unmet need exists and that it is caused largely by lack of information on the part of elders' and by agencies' difficulties in identifying elders in need. One-half of rural elders who did not use transit were unaware that it was provided. The level of knowledge among women was much higher in smaller towns than inlarger communities. Elders who have actually used transit have a favorable opinion of it. Transit is seen as safe and dependable. Riders consider drivers to be courteous and few report that trips take too long. The level of satisfaction reported is ...
Toxic dilatation of the colon following barium enema examination during the quiescent stage of chronic ulcerative colitis. Report of a case.

A case is presented of toxic dilatation of the colon following barium enema examination after an 11-year remission of chronic ulcerative colitis. The role of this X-ray examination in chronic ulcerative colitis is discussed.
MEASURING AND ANALYZING CLASS INEQUALITY WITH THE GINI INDEX INFORMED BY MODEL-BASED CLUSTERING

The most widely used measure for studying social, economic, and health inequality is the Gini index/ratio. Whereas other measures of inequality possess certain useful characteristics, such as the straightforward decomposability of the generalized entropy measures, the Gini index has remained the most popular, at least in part due to its ease of interpretation. However, the Gini index has a limitation in measuring inequality. It is less sensitive to how the population is stratified than how individual values differ. The twin purposes of this paper are to explain the limitation and to propose a model-based method—latent class/clustering analysis for understanding and measuring inequality. The latent cluster approach has the major advantage of being able to identify potential “classes” of individuals who share similar levels of income or one or more other attributes and to assess the fit of the model-based classes to the empirical data, based on different cluster distributional assumptions and the number of ...
Towards Balancing Medium Access Energy Trade-Offs in Wireless Sensor Networks

In this paper we explore the design of multi-modal MAC for wireless ad hoc and sensor networks that dynamically adapt its behavior in order to minimize the energy to delivery ratio under a wide variety of network loads. The prime motivation is to balance the inherent trade-off between the energy wasted in collisions and the energy expended by collision avoidance handshake mechanisms. Towards this objective, the study goes through two phases. First, we explore the space of MAC modes subject to the constraint that different access schemes can inter-operate. Accordingly, we limit our attention to modes within the non-slotted random access paradigm. Second, we analyze, with the aid of detailed network simulations, the energy performance trade-offs of four variations of the CSMA/CA access scheme. Finally, we shed some light on the problem of dynamically switching between different modes depending on the network loading conditions and application QoS requirements. Initial results reveal interesting observations related to the energy/delivery contribution of channel reservation and single-hop acknowledgment packets under a wide variety of temporal network loads
Another Look at a Moral Statute of Limitations on Injustice

This paper addresses the question of whether a statute of limitations on injustice is morally justified. Rectificatory justice calls for the ascription of a right to rectification once an injustice has been perpetrated. To claim a moral statute of limitations on injustice is to claim a temporal limit on the moral legitimacy of rights to rectification. A moral statute of limitations on injustice (hereafter MSOL) establishes an amount of time following injustice after which claims of rectification can no longer be valid. Such a statute would put a time limit on the life of moral rights to rectification. Since ascribing a right to rectification for an injustice is a requirement of justice, and since the temporal limit called for by a moral statute of limitations on injustice is a constraint on that requirement, the idea of a statute of limitations on injustice is morally jutified only if we have good reasons for accepting this constraint. In “The Morality of a Moral Statute of Limitations on Injustice” I argued that neither the best arguments then extant in the philosophical literature, nor the arguments I proposed in favor of a MSOL, succeed in providing good reasons for accepting the idea as morally legitimate. I concluded, therefore, that a MSOL is not justified. Several discussions that have emerged since then suggest some support for a MSOL. My aim in this paper is to show that a MSOL remains unjustified by showing that none of the arguments arising from these discussions succeed.
Huntington's disease: Alterations in GABA and benzodiazepine receptors in the human brain

Abstract Huntington's disease (HD) is a neurological disorder characterized by severe movement disorders, dementia and widespread neuronal degeneration in the corpus striatum and cerebral cortex. In the caudate and putamen there was a significant decrease in GABA receptor binding in HD. In the frontal cortex, GABA receptors were not altered in this disorder. In the HD putamen, both BDZ receptor density and the affinity of BDZ receptors for 3 H-flunitrazepam decreased. In the HD frontal cortex and cerebellum, only an increase in receptor density was detected. The results of the present study suggest that striatal GABA receptors and BDZ receptors are lost in HD. The affinity charges of BDZ receptors found in the HD putamen are probably associated with the lower levels of GABA found in that region and the increases in BDZ receptors in the cerebellum and cortex may be related to decreases in the levels of some endogenous substance that acts upon these receptors.
Comparison and summary of tau topological branching fractions

After nearly two decades of work on topological branching fractions, it appears that an experimental consensus is forming. The new world average is 14.54 ± 0.20.
Epidural steroid injections for lumbar spinal stenosis

Degenerative lumbar stenosis is a common source of pain and disability in the elderly. It presents clinically with a variety of symptoms, though neurogenic claudication is the hallmark. There is a multifactorial pathogenesis to lumbar stenosis and its symptoms, and thus, there are multiple management approaches available. Epidural steroid injections (ESIs) are a popular choice in management, however, the literature is vague in definitive support of their use, and providers that utilize injections can use variable techniques to access the spinal canal in order to deposit the steroid at the appropriate site. This article will review degenerative lumbar stenosis in general and focus on the use of ESIs to better define their role in this management process. In addition, the evidence to discern the optimal injection route will be presented.
Estimating the prevalence of inadequate nutrient intakes in a healthy elderly population: Validity of classification and probability methodologies

Abstract The evaluation of dietary intake is an essential part of nutritional surveys and provides estimates of risks of dietary deficiency. In order to test the validity of these estimates, the prevalence of inadequate intake in a healthy elderly population (n=82) was calculated from a 7-day food record using two different methods and then compared to the prevalence of nutritional deficiencies evidenced by laboratory assessments. With the probability method, the risk for each individual to have an intake below its own requirement is calculated. In contrast, the classification method compares the intake of each subject to a cut-off point set a priori below which the intake is presumed to be inadequate. For each nutrient considered, probability analyses consistently yielded a predicted prevalence lower than the currently used classification method (
Uniaxial textured (001) metal film formation via YBa2Cu3O7/SrTiO3/metal trilayers

Abstract The formation of (001)-oriented uniaxially textured metal layers on randomly oriented surfaces using textured oxide buffer layers is described. The initial formation of uniaxial texture is through the deposition of polycrystalline YBa 2 Cu 3 O 7 − x films, which has a strong tendency to form in the c -axis perpendicular orientation due to strong surface energy anisotropy. An epitaxial SrTiO 3 cap layer on the (001) textured YBa 2 Cu 3 O 7− x , layer retards decomposition of the oxide surface under high temperature, low pressure conditions that are suitable for metal epitaxy. The resulting metal surfaces have a strong uniaxial texture and may prove useful in applications where (001) uniaxial texture in metal films is desired.
Stock-scion interactions of normal and fruit ripening mutants rin and nor in tomato

Scions of the non-ripening rin and nor tomato strains (Lycopersicum esculentum Mill.) were grafted on normal understock plants (cv. Rutgers) in an effort to study the influence of roots and vegetative tissue on the ripening behavior of the tomato fruit. Receiprocal grafts of ‘Rutgers’ scions on rin and nor understocks as well as grafted and ungrafted controls were also established. No alteration in the ethylene, and CO2 evolution and color development of either mutant fruits on normal understock or of normal fruits on mutant understock occurred. We suggest that the inability of rin and nor mutant fruits to ripen normally stems either from the presence in mutant fruit of a non-translocatable ripening inhibitor, or from the absence of a non-translocatable ripening factor.
A Deterministic Reduction for the Gap Minimum Distance Problem

Determining the minimum distance of a linear code is one of the most important problems in algorithmic coding theory. The exact version of the problem was shown to be NP-complete by Vardy. The gap version of the problem was shown to be NP-hard for any constant factor under a randomized reduction in an earlier work. It was shown in the same paper that the minimum distance problem is not approximable in randomized polynomial time to the factor 2log1-ϵn unless NP ⊆ RTIME(2polylog(n)). In this paper, we derandomize the reduction and thus prove that there is no deterministic polynomial time algorithm to approximate the minimum distance to any constant factor unless P=NP. We also prove that the minimum distance is not approximable in deterministic polynomial time to the factor 2log1-ϵn unless NP ⊆ DTIME(2polylog(n)). As the main technical contribution, for any constant 2/3 <; ρ <; 1, we present a deterministic algorithm that given a positive integer s , runs in time poly(s) and constructs a code C of length poly(s) with an explicit Hamming ball of radius ρd(C), such that the projection at the first s coordinates sends the codewords in the ball surjectively onto a linear subspace of dimension s , where d(C) denotes the minimum distance of C. The codes are obtained by concatenating Reed-Solomon codes with Hadamard codes.
Change impact analysis for object-oriented programs

Small changes can have major and nonlocal effects in object-oriented languages, due to the use of subtyping and dynamic dispatch. This complicates life for maintenance programmers, who need to fix bugs or add enhancements to systems originally written by others. Change impact analysis provides feedback on the semantic impact of a set of program changes. This analysis can be used to determine the regression test drivers that are affected by a set of changes. Moreover, if a test fails, a subset of changes responsible for the failure can be identified, as well as a subset of changes that can be incorporated safely without affecting any test driver.
Effects of cyclic AMP, its mechanism of action, and comments on the energetics of its 3′-phosphate bond*

Summary Reviewing these results I should like to call your attention to a relatively unusual manner of regulation that has appeared here. The activation by cyclic AMP of histone-kinase preparations from reticulocyte hemolysate and adrenal cortex homogenate was shown to be due to binding of cyclic AMP to an inhibitor, thus separating it from the enzyme-inhibitor complex. Sucrose gradient centrifugation in the presence of cyclic AMP was shown to split a 140,000 mol. wt. molecule, which required cyclic AMP for activity, into an 80,000 mol. wt. protein-cyclic AMP complex and a 60,000 mol. wt. enzyme, fully active without cyclic AMP. The cyclic AMP binding is thus not related here directly to kinase activity but causes activation by dissociation through displacement of an inhibitor from the inhibitor-enzyme complex. It should be noted that by no means all effects of cyclic AMP can be related, so far, to a stimulation of a protein kinase activity. The very interesting function of cyclic AMP in counteracting metabolite repression in E. coli ( 23. , 24. ) has recently been related to cyclic AMP complexing with a protein ( 25. , 26. ) to activate transcription of the mRNA responsible for production of metabolite-repressed enzyme activities. It seems unlikely to me that the bacterial protein involved in this release will be a protein phosphokinase.