cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal running speed and the evolution of hominin hunting strategies.

Recent discussion of the selective pressures leading to the evolution of modern human postcranial morphology, seen as early as Homo erectus, has focused on the relative importance of walking versus running. Specifically, these conversations have centered on which gait may have been used by early Homo to acquire prey. An element of the debate is the widespread belief that quadrupeds are constrained to run at optimally efficient speeds within each gait, whereas humans are equally efficient at all running speeds. The belief in the lack of optimal running speeds in humans is based, however, on a number of early studies with experimental designs inadequate for the purpose of evaluating optimality. Here we measured the energetic cost of human running (n = 9) at six different speeds for five minutes at each speed, with careful replicates and controls. We then compared the fit of linear versus curvilinear models to the data within each subject. We found that individual humans do, in fact, have speeds at which running is significantly less costly than at other speeds (i.e., an optimal running speed). In addition, we demonstrate that the use of persistence hunting methods to gain access to prey at any running speed, even the optimum, would be extremely costly energetically, more so than a persistence hunt at optimal walking speed. We argue that neither extinct nor extant hominin populations are as flexible in the chosen speeds of persistence hunting pursuits as other researchers have suggested. Variations in the efficiency of human locomotion appear to be similar to those of terrestrial quadrupeds.
A cell-free amino acid incorporating system from Azotobacter vinelandii.

Abstract Cell-free extracts were prepared from exponentially growing cultures of Azotobacter in which metabolism was halted rapidly. The cells were disrupted by osmotic shock. Amino acid incorporation into polypeptide was dependent upon ribosomes, 140,000 g supernatant fraction (S-140), ATP, an energy generating system, a critical concentration of Mg 2+ (4 m m ), an optimal pH (7.2), tRNA and optimal concentrations of spermidine (0.2 m m ) and K + (0.1 m ). Poly U and poly A directed the synthesis of polyphenylalanine and polylysine respectively. Escherichia coli tRNA could substitute for Azotobacter tRNA. Ribonuclease, streptomycin, puromycin and chloramphenicol inhibited protein synthesis. Endogenous amino acid incorporation proceeded linearly for ten minutes and leveled off after 20 minutes. Poly U-directed protein synthesis proceeded linearly for periods up to 1 hour. Frozen ribosomes and S-140 are stable if frozen quickly and stored in liquid nitrogen. Endogenous incorporation of phenylalanine occurs at 0 ° to a limited extent but is highest within the range of 30–40 °. Ribosomal activity reflected the growth phase of the organism, the rapidity of cessation cell metabolism, the preincubation of ribosomes and the mode of cell rupture.
Relaxation dynamics of silicon quantum dots in silica

Silicon ions were implanted into fused silica substrates at doses of 1 by 1021, 2 by 1021, 5 by 1021, and 1 by 1022 ions/cm3. The implanted substrates were subsequently annealed at 1100 degrees C for one hour in a reducing atmosphere. Optical absorption spectra recorded after the annealing treatment showed absorption onsets at 316, 373, 434 and 493 nm for substrates implanted with 1 by 1021, 2 by 1021, 5 by 1021, and 1 by 1022 ions/cm3 respectively. Static photoluminescence (PL) measurements indicated red emission between 720 and 770 nm with a slightly increasing red shift with ion dose. Time resolved PL at room temperature revealed slow and fast lifetimes which increased with decreasing temperature. TEM studies showed that the particles size increased with increasing ion dose with typical particle sizes ranging between 2 and 5 nm indicating quantum confinement of the exciton which can account for the blue shift in the absorption edge with decreasing ion dose. However, the maxima in the PL spectra for all ion doses are relatively independent of the ion dose and are strongly Stokes shifted from the absorption spectra suggesting that radiative recombination occurs from a common luminescent center, possibly a surface or interfacial state in the SiOx layer surrounding the nanocrystal.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Improved algorithms for mapping pipelined and parallel computations

Recent work on the problem of mapping pipelined or parallel computations onto linear array, shared memory, and host-satellite systems is extended. It is shown how these problems can be solved even more efficiently when computation module execution times are bounded from below, intermodule communication times are bounded from above, and the processors satisfy certain homogeneity constraints. The improved algorithms have significantly lower time and space complexities than the more general algorithms: in one case, an O(nm/sup 3/) time algorithm for mapping m modules onto n processors is replaced with an O(nm log m) time algorithm, and the space requirements are reduced from O(nm/sup 2/) to O(m). Run-time complexity is reduced further with parallel mapping algorithms based on these improvements, which run on the architectures for which they create mappings. >
Polyethylene, Linear Low Density

Linear low density polyethylene (LLDPE) resins are polyethylene (PE) plastics with densities in a 0.915–0.925-g/cm3 range. They belong to the family of semicrystalline ethylene–α-olefin copolymers, which are produced in catalytic polymerization reactions. Due to reduced crystallinity, all these copolymers have densities lower than that of the ethylene homopolymer, ∼0.96 g/cm3. This family of PE resins includes medium density PE (MDPE, 0.940–0.925 g/cm3), LLDPE (0.925–0.915 g/cm3), and very low density PE (VLDPE, < 0.915 g/cm3). A variety of resins described by the general term LLDPE differ in several respects: the type of an α-olefin used in copolymerization with ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, or 1-octene; the content of the α-olefin in a copolymer, which varies from 1 mol% in MDPE to 2.5–3.5 mol% in LLDPE and to 10–15 mol% in VLDPE; the density and crystallinity of the resin, and the compositional uniformity of the copolymers. The LLDPE resins are produced in industry with three classes of catalysts: Ziegler catalysts based on titanium compounds, several types of catalysts utilizing metallocene complexes, and Phillips catalysts based on chromium oxides. The resins are manufactured in gas-phase, solution, and slurry polymerization processes. The LLDPE resins are major commodity products with a combined 2005 worldwide manufacture volume of ∼15×106 ton/year, ∼25% of the overall polyethylene production. Film is the largest application market for LLDPE resins. The film is used to manufacture grocery sacks, bags for produce, trash bags, bags for merchandise packaging, garment, laundry and dry cleaning bags, and ice bags. The LLDPE film is also used for nonpackaging applications, such as industrial sheeting and agricultural mulch film. High clarity film produced with LLDPE resins manufactured with metallocene catalysts is widely used for food packaging and in numerous medical applications. Injection molding products represent the second largest market for LLDPE, mostly for housewares. These resins are also used for blow molding of bottles and drums; for rotational molding of toys, large containers, and tanks; for pipe and tubing; and for wire coating in electrical and telephone industry. The VLDPE is a subclass of LLDPE resins; its density is < 0.915 g/cm3 and it is mostly used for food packaging of fresh produce, milk, meat, cheese, etc, as well as for the manufacture of multilayer coextruded film. These resins are also blended with other polyethylene and polypropylene-based resins to enhance clarity, sealability, and toughness of the materials. Keywords: polyethylene; linear low density; copolymer; molecular structure; catalysts; ziegler catalysts; metallocene; polymerization; chromium oxide; rheology; film; injection molding; blow molding; pipe; tubing; wire
Solution conformation of Lewis a-derived selectin ligands is unaffected by anionic substituents at the 3'- and 6'- positions

The selectins are a family of proteins that mediate leukocyte tethering and rolling along the vascular endothelium. E-, P-, and L-selectin recognize various derivatives of the Lewis(a) and Lewis(x) trisaccharides. The distribution of negative charges on the Lewis(a) and Lewis(x) oligosaccharides appears to be an important factor in their binding by the selectins. Previous work exploring this electrostatic dependence found that a series of synthetic anionic trisaccharides, 3'-sulfo, 3'-phospho, 6'-sulfo, and 3',6'-disulfo Lewis(a)-(Glc), exhibited differing selectin inhibitory efficacies. To explore the possibility that these differences arise from conformational differences between the sugars, the solution structures of these trisaccharides were determined using NMR and molecular dynamics simulations. Interproton distances and interglycosidic torsion angles were determined at 37 degrees C using NOESY buildup curves and 1D LRJ experiments, respectively. Data from both experiments agreed well with predictions made from 2000 picosecond unrestrained molecular dynamics simulations. We found that 3'-sulfation did not alter the core Lewis(a) conformation, a finding that reaffirms the results of previous study. In addition, we found that sulfation at the 6' position also leaves the trisaccharide conformation unperturbed. This is significant because the proximity of the 6'-sulfate group to the fucose ring might have altered the canonical Lewis (a) structure. The disulfate exhibited greater flexibility than the other derivatives in dynamics simulations, but not so much as to affect NOE and heteronuclear coupling constant measurements. Taken together, our findings support the use of Lewis(a) as a template onto which charged groups may be added without significantly altering the trisaccharide's structure.
Connectivity and the Governance of Multilevel Social-Ecological Systems: The Role of Social Capital

We discuss the challenges confronting environmental governance caused by the increasing connectivity of resource-use systems and the growing functional interdependencies of ecological and social systems. We take as a point of departure the case of the Xingu Indigenous Park (PIX) in Brazil and its surrounding agro-industrial region. This case provides a basis for reviewing the literature on resource governance, including both points of consensus and contentious issues. We argue that no fixed spatial or temporal level is appropriate for governing ecosystems and their services sustainably, effectively, and equitably. We point to the need to recognize the multilevel nature of such problems and the role of institutions in facilitating cross-level environmental governance as an important form of social capital that is essential for the long-term protection of ecosystems and the well-being of different populations.
Caspofungin Acetate for Treatment of Invasive Fungal Infections

OBJECTIVETo briefly discuss the changing epidemiology of fungal infections and review currently available agents; provide a review of caspofungin; and discuss its pharmacology, pharmacokinetics, dosing guidelines, safety and efficacy, and role in the treatment of invasive fungal infections as it relates to current antifungal therapy.DATA SOURCESA MEDLINE (1966 to August 2002) database search using key words caspofungin, echino candins, fungal infections, and invasive aspergillosis, was completed to identify relevant articles including reviews, recent studies, treatment guidelines, and data from Merck and Company.STUDY SELECTIONIn vitro studies and all clinical trials were evaluated to summarize the clinical efficacy and safety of caspofungin.DATA SYNTHESISThe incidence of fungal infections is increasing as the population at risk expands. Cost, resistance, and morbidity and mortality are key issues. Adding to the antifungal armamentarium is necessary to address these therapeutic dilemmas. Caspofungin is th...
Species-specific behavioral patterns correlate with differences in synaptic connections between homologous mechanosensory neurons

We characterized the behavioral responses of two leech species, Hirudo verbana and Erpobdella obscura, to mechanical skin stimulation and examined the interactions between the pressure mechanosensory neurons (P cells) that innervate the skin. To quantify behavioral responses, we stimulated both intact leeches and isolated body wall preparations from the two species. In response to mechanical stimulation, Hirudo showed local bending behavior, in which the body wall shortened only on the side of the stimulation. Erpobdella, in contrast, contracted both sides of the body in response to touch. To investigate the neuronal basis for this behavioral difference, we studied the interactions between P cells. Each midbody ganglion has four P cells; each cell innervates a different quadrant of the body wall. Consistent with local bending, activating any one P cell in Hirudo elicited polysynaptic inhibitory potentials in the other P cells. In contrast, the P cells in Erpobdella had excitatory polysynaptic connections, consistent with the segment-wide contraction observed in this species. In addition, activating individual P cells caused asymmetrical body wall contractions in Hirudo and symmetrical body wall contractions in Erpobdella. These results suggest that the different behavioral responses in Erpobdella and Hirudo are partly mediated by interactions among mechanosensory cells.
Simulating the SU(2) sector of the standard model with dynamical fermions

Abstract The two-generation SU(2) sector of the standard model with zero Yukawa couplings is studied on the lattice. The results from analytic studies and simulations with quenched fermions are reviewed. The methods and results of a Langevin simulation with dynamical fermions are presented. Implications for the strongly coupled standard model are mentioned.
Population-level changes in folate intake by age, gender, and race/ethnicity after folic acid fortification.

Objectives. We sought to quantify the impact of the 1998 US Food and Drug Administration (FDA) folic acid fortification policy by estimating folate intake at the population level. Methods. We analyzed total folate intake levels (from food and supplements) according to gender, age, and race/ethnicity, using data from 2 National Health and Nutrition Examination Surveys. We measured pre- and postfortification folate intake distributions, adjusted for measurement error, and examined proportions of the population who reached certain thresholds of daily total folate intake. Results. Mean daily food and total folate intake increased by approximately 100 µg/day after fortification. The proportion of women aged 15‐44 years who consume more than 400 µg/day of folate has increased since fortification, but has not yet reached the FDA’s 50% target and varies by race/ethnicity from 23% to 33%. Among persons aged 65 years and older who may be at risk for masking a vitamin B 12 deficiency, the percentage who consume more than 1000 µg/day (the “tolerable upper intake level”) has at least doubled among Whites and Black men, but has remained less than 5% for all groups. Conclusions. Since fortification, folic acid intake among the US population has increased, and there are substantial variations by age, gender, and race/ethnicity. (Am J Public Health. 2006;96:2040‐2047. doi:10.2105/AJPH.2005.067371)
Reducing the Relational Distance between Actors A Case Study in School Reform

The research reported here centers on two African American principals and their efforts to include parents in a school restructuring program. One was successful, whereas the other was not. The findings are presented within a sociological frame work as principals' attempts to reduce the relational distance between home and school. Although some have argued that this distance is countered by matching actors on racial characteristics, these results indicate that the problem is somewhat more complex. Rather, one principal's ability to correctly read the surrounding community and his relationship to it emerged as the most important factor in determining his success in minimizing the home/school gap.
Infection: Treating recurrent C. difficile infection—the challenge continues

Treatment of recurrent Clostridium difficile infection is challenging. New research now replicates human disease in a mouse model, shedding light on why antibiotics often fail to prevent further recurrences and demonstrating that targeted manipulation of the gut microbiota could be a feasible treatment option.
Examining the Role of Cuticular Hydrocarbons in Firefly Species Recognition

During animal courtship, multiple signals transmitted in different sensory modalities may be used to recognize potential mates. In fireflies (Coleoptera: Lampyridae), nocturnally active species rely on long-range bioluminescent signals for species, sex, and mate recognition, while several diurnally active species rely on pheromonal signals. Although in many insects non-volatile cuticular hydrocarbons (CHC) also function in species and sex discrimination, little is known about the potential role of CHC in fireflies. Here, we used gas chromatography to characterize species and sex differences in the CHC profiles of several North American fireflies, including three nocturnal and two diurnal species. Additionally, we conducted behavioral bioassays to determine whether firefly males (the searching sex) were differentially attracted to extracts from conspecific vs. heterospecific females. Gas chromatography revealed that nocturnal Photinus fireflies had low or undetectable CHC levels in both sexes, while diurnal fireflies showed higher CHC levels. No major sex differences in CHC profiles were observed for any firefly species. Behavioral bioassays demonstrated that males of the diurnal firefly Ellychnia corrusca were preferentially attracted to chemical extracts from conspecific vs. heterospecific females, while males of the remaining species showed no discrimination. These results suggest that while CHC may function as species recognition signals for some diurnal fireflies, these compounds are unlikely to be important contact signals in nocturnal Photinus fireflies.
Economics Of Summer Course Scheduling

This paper addresses some of the relevant issues that University administrators face when determining a policy for academic coursework offered during the summer period, and the development of a mathematical model that may be used to guide management policy. It is suggested that the economic ramification of summer course policies may not be well understood, including understanding the potential long-term effect of discounting on summer per-credit charges. An empirical example is provided to demonstrate how administrators may utilize optimization and economic principles to address summer course pricing in an imperfect and ambiguous market.
3D Computational Modeling and Simulation of Cell Motion on Adhesive Surfaces in Shear Flow

A three-dimensional computational fluid dynamic (CFD) model is presented to simulate transient rolling adhesion and deformation of leukocytes over a P-selectin coated surface in shear flow. The computational model is based on immersed boundary method for cell deformation, and stochastic Monte Carlo simulation for receptor/ligand interaction. The model is shown to predict the characteristic ‘stop-and-go’ motion of rolling leukocytes. The objective here is to understand the coupling between external shear flow, cell deformation, microvilli deformation and various biophysical parameters that govern the formation of selectin bonds. We observe that compliant cells roll more stably with lesser fluctuations. Adhesion is seen to occur via multiple tethers, but often one tether is sufficient to support rolling. The force loading on individual microvillus is not continuous, rather occurs in steps. Further, it is also shown that only the microvilli whose undeformed length is above a certain cut off length, participate in bond formation and the cutoff length reduces with increasing cell rigidity.Copyright © 2008 by ASME
Hoxb13 knockout adult skin exhibits high levels of hyaluronan and enhanced wound healing

In contrast to adult cutaneous wound repair, early gestational fetal cutaneous wounds heal by a process of regeneration, resulting in little or no scarring. Previous studies indicate that down-regulation of HoxB13, a member of the highly conserved family of Hox transcription factors, occurs during fetal scarless wound healing. No down-regulation was noted in adult wounds. Here, we evaluate healing of adult cutaneous wounds in Hoxb13 knockout (KO) mice, hypothesizing that loss of Hoxb13 in adult skin should result in enhanced wound healing. Tensiometry was used to measure the tensile strength of incisional wounds over a 60-day time course; overall, Hoxb13 KO wounds are significantly stronger than wild-type (WT). Histological evaluation of incisional wounds shows that 7-day-old Hoxb13 KO wounds are significantly smaller and that 60-day-old Hoxb13 KO wounds exhibit a more normal collagen architecture compared with WT wounds. We also find that excisional wounds close at a faster rate in Hoxb13 KO mice. Biochemical and histochemical analyses show that Hoxb13 KO skin contains significantly elevated levels of hyaluronan. Because higher levels of hyaluronan and enhanced wound healing are characteristics of fetal skin, we conclude that loss of Hoxb13 produces a more "fetal-like" state in adult skin.
Optically triggered switching of optically thick YBCO films

Thin films of high-T/sub c/ superconducting material were used to construct two different types of opening switches: the photoresistive switch and the inductively coupled switch. The former show two distinct switching components in 8000-AA films consisting of a slow bolometric response and a faster nonbolometric response. The fast nonbolometric component had risetimes of approximately 4 ns and falltimes of approximately 6 ns. The slower component was identified to be thermal in origin and was in good agreement with the one-dimensional heat flow model used to simulate the thermal photoresponse. The inductively coupled switch is a contactless switch where the superconducting film screens the flux coupling between two coils of a transformer. The optically induced switching was achieved with risetimes of approximately 50 ns. with a multiturn output coil. Short (150-ps) laser pulses containing energies of up to 3 mJ are used in both cases to perform the switching. >
Emotions, Reflexivity, and Action: An Interactionist Analysis'

Data from a variety of sources are used to explore the relation between emotions and cognitions. Instead of positing the relation between cognitions and emotions, we explore the variety of ways that people experience their thoughts and feelings. A typology demonstrates four ways an individual may respond to a situation: reflexive and emotional, unreflexive and emotional, reflexive and without feeling, and neither reflexive nor emotional. In addition to describing these experiences, we examine the circumstances that give rise to them. By recognizing that individuals can suspend reflexivity, we begin to bridge the gap between the positivist and interactionist conceptions of emotion.
Touchpad Input for Continuous Biometric Authentication

Authentication is a process which is used for access control in computer security. However, common existing methods of authentication, which are based on authentication during the login stage, are insecure due to the lack of authentication after the initial instance. Ideally, authentication should be continuous and should not interfere with a user’s normal behavior as to not create an inconvenience for the user. Behaviometric identification, for example, verifies a user’s identity based on his behavior, both continuously and without interruption. This work shows that it is possible, with great accuracy, to identify different users based on their touchpad behaviors. While linear classifiers proved ineffective at classifying touchpad behavior, kernel density estimation and decision tree classification each proved capable of classifying data sets with over 90% accuracy.
Leiomyofibroma of the uterus and endometrial carcinoma

Summary The frequent coexistence of fibromyomas of the uterus and endometrial carcinoma has been the subject of considerable conjecture and investigation regarding its significance from both clinical and etiologic standpoints. It has never been satisfactorily established, however, that the high incidence of fibroids can be considered as peculiar to or characteristic of corpus carcinoma, and not just simply a reflection of the frequent occurrence of fibromyomas. In order to remedy the surprising dearth of information on this essential and basic point, a study was made of hysterectomies at Harper Hospital. Among 2,246 consecutive abdominal hysterectomy cases there were 44 with endometrial carcinoma, an incidence of 2 per cent. In this series there were 1,672 with a diagnosis (1,389 primary and 283 secondary) of fibromyomas, of which only 15, or 0.9 per cent, showed carcinoma. In marked contrast, the group of 574 without fibroids had an incidence of 29, or 5.1 per cent, with uterine fundus cancer. As a. check on this unexpected finding, a series of 50 endometrial carcinoma cases were compared with a like number of noncancerous instances, falling into the same age groups, and in whom the operations had been done for various reasons other than fibromyomas. Of the carcinomatous uteri there were 18 with fbroids, while in the other group the number was 23. There is no evidence in these data to indicate that fibromyomas of the uterus and endometrial carcinoma have an affinity for each other, but rather the reverse.
I13 Variability In Interval Production Is Due To Timing Dependent Deficits In Early Huntington’s Disease

Background In Huntington’s disease (HD) increased variability is seen in performance of motor tasks that require implicit control of timing. We examined if timing variability was also evident in an explicit interval-timing task. Methods Sixty subjects (21 controls, 19 manifest HD and 20 pre-manifest HD) performed a single interval production task with three target intervals (1.1s, 2.2s, 3.3s). We analysed accuracy (proportional error) and precision (standard deviation) across groups and intervals. Results No differences were seen in accuracy across groups or intervals. Precision was significantly lower in manifest (p = 0.0001) and pre-manifest HD (p = 0.04) compared with controls. This was particularly true for pre-manifest subjects close to diagnosis (based on probability of diagnosis in five years). Precision was correlated with proximity to diagnosis (r2=0.3, p Conclusions Timing precision is impaired before clinical diagnosis in Huntington’s disease. Slope analysis suggests that timing variability (decreased precision) was due to deficits in timing dependent processes. Our results provide additional support for the proposal that the basal ganglia are implicated in central timekeeping functions. Since the single interval production task was sensitive to deficits in pre-manifest HD, temporal precision may be a useful outcome measure in future clinical trials.
Progress of Rorty and Truth of Confucianism

Although often regarded as a relativist, Richard Rorty responded by denying it himself. In the process of response and denial, Rorty developed his view of and hope. His recent view of progress and hope for progress has gained further development and expressed two Confucian ideas in a better way. That is to say that moral progress means expanding the domain of those who we regard as “ourselves” and that we don’t have to take a position of moral universalism to make such progress. Meanwhile, Confucius and Rorty may differ first in place of distinctions in moral education and then in function of metaphysics in moral progress. And their arguments can be concluded that Rorty’s Confucianism will be a better Confucianism and that the Confucian Rorty will be a better Rorty.
Techniques in Swept Frequency Capacitive Sensing: An Open Source Approach.

This paper introduces a new technique for creating Swept Frequency Capacitive Sensing with open source technology for use in creating richer and more complex musical gestures. This new style of capacitive touch sensing is extremely robust compared to older versions and will allow greater implementation of gesture recognition and touch control in the development of NIMEs. Inspired by the Touche project, this paper discusses how to implement this technique using the community standard hardware Arduino instead of custom designed electronics. This sensing technique requires only passive components and can be used to enhance the touch sensitivity of many conductive materials, even biological materials such as plants. This paper also introduces a new Arduino Library, SweepingCapSense, which simplifies the coding required to implement this technique. Lastly, this paper will discuss its use in the project known as Cultivating Frequencies.
Viral Glycoprotein-Mediated Cell Fusion Assays Using Vaccinia Virus Vectors

The vaccinia virus-based expression of viral envelope glycoprotein genes-derived from enveloped viruses that infect their respective host cells through a pH-independent mechanism of membrane fusion-has been a powerful tool in helping to characterize these important attachment and fusion proteins. The cellular expression of these viral envelope glycoproteins has allowed for the measurement of membrane fusion events using cell-cell fusion or syncytia formation. This method has been enhanced by the addition of a reporter-gene system to the vaccinia virus-based cell-cell fusion assay. This improvement has provided a high-throughput and quantitative aspect to this assay, which can serve as a surrogate for virus entry and is therefore ideally suited in the characterization of numerous enveloped viruses, including biological safety level-4 (BSL-4) agents. This chapter will detail the methods of the vaccinia virus-based reporter-gene fusion assay and how it may be used to characterize the fusion mediated by the BSL-4-classified Hendra and Nipah viruses.
Gastrointestinal complications of chronic spinal cord injury.

ABSTRACTGastrointestinal problems are important in the chronic stage of spinal cord injury. We review the literature on problems of specific segments of the alimentary tract in this setting and add observations based on clinical experience. Emphasis is placed on the colon and rectum, where most clincially apparent problems occur. While bowel management programs are often successful in the near-term, long-term dysfunctions are common and difficult to treat. Studies to determine colonic transit time and rectal physiologic responses are useful to provide scientific basis of management of such patients. More information is needed on the relative roles of extrinsic and intrinsic nervous system in Gl function. (J Amer Paraplegia Soc 1991;14: 175–81)
Thinking big? Ghana, small reactors, and nuclear power

Abstract Ghana has been seen as a potential market for small nuclear reactors and Ghanaian nuclear officials have, on occasion, expressed an interest in such reactors. However, Ghana seems to be heading towards procuring a reactor from Russia with a capacity of 1000–1200 MW. A power plant with such a large power generation capacity is not appropriate to Ghana’s limited electricity grid or its financial circumstances. This paper examines the likely reasons for this focus and argues that despite greater government interest in setting up nuclear reactors, Ghana’s nuclear establishment may not have the political clout to force through the purchase of a reactor, and has therefore attempted to position itself as a complete, one-stop solution to Ghana’s electricity crisis, by calling for the construction of just one or two large nuclear power plants. The paper draws on the role of discursive elements in energy policy making, discusses the policy implications of this reactor choice, and offers evidence for the proposition that decision about nuclear power are not made on the basis of merely techno-economic considerations but are driven by a range of social and political factors.
Cellular IoT for Mobile Autonomous Reporting in the Smart Grid

Wireless access technologies are being embedded in utility meters, health devices, public safety systems, among others. These devices have low processing power and communicate at low data rates. New communication standards are being developed to support these machine-type communications MTC, such as Cellular Internet of Things CIoT, which is being developed by the third generation partnership project 3GPP. CIoT introduces cooperative ultra-narrow band C-UNB communications. It supports ad-hoc uplink transmissions, delay-tolerant downlink transmissions, and a simple authentication scheme. The C-UNB approach is proposed for Mobile Autonomous Reporting MAR applications, but it is not clear if it can be used for smart grid systems, such as sensors and smart meters in the Advanced Metering Infrastructure AMI. In this paper, the authors review the C-UNB approach, study its performance in terms of collision rate and throughput, and discuss its potential for smart grid reporting applications.
Nuclear magnetic resonance Knight shifts in the presence of strong spin–orbit and crystal-field potentials

In recent years there has been increasing interest in materials with strong spin–orbit coupling (SOC). Nuclear magnetic resonance is a valuable microscopic probe of such systems because of the hyperfine interactions between the nuclear spins and the electron degrees of freedom. In materials with weak SOC the NMR Knight shift contains two contributions: one from the electron orbital susceptibility and the other from the electron spin susceptibility. These contributions can be separated by plotting the Knight shift versus the bulk susceptibility and extracting the slope and intercept. Here we examine the case where the SOC is non-negligible, in which case the slope and intercept are no longer simply related to these two contributions. These results have important implications for NMR studies of heavy fermions, as well as 4d and 5d systems.
Ultrasonic Imaging of Tumor Nodules in the Human Liver: An In Vitro Study

The use of ultrasound in tumor location has been well documented (1,2). In this work a direct ultrasonic image of human tissue is produced by using a modified Sokolof ultrasonic image converter. The system used in our laboratory is shown in Figure 1. A continuous ultrasonic wave signal whose frequency is 3.58 MHz is generated by a piezoelectric transmitter. The generated ultrasonic waves propagate through water contained within the tank. The tissue sample is inserted into the ultrasonic field. Transmitted ultrasound waves strike the piezoelectric target of the Sokolof tube after having passed through the entire thickness of the tissue sample. During this passage, the ultrasonic waves undergo reflections and phase shifts. The resulting amplitude and phase changes are converted into a video signal which is displayed on a 19” color TV monitor.
Effects of processing parameters and blade patterns on continuous pharmaceutical powder mixing

Abstract The present study summarizes the experimental characterization of a new continuous powder mixer (GCG-70 by Glatt®) using common pharmaceutical ingredients. The powder hold-up and residence time distribution were used to characterize the bulk behavior of the mixer as a function of impeller rotational speed, total throughput (mass flow rate) and blade configuration. The relative standard deviation (RSD), calculated from samples taken at the outlet of the blender, was used to characterize its mixing performance. The hold-up and the mean residence time decreased with increasing impeller rotational speed. The mean centered variance and the number of blade passes increased with increasing impeller rotational speed. The effect of the blade configuration on the mixing dynamics diminished as the rotation rate increased. The hold-up and mean residence time were sensitive enough to demonstrate the effects of blade configurations. The mixing performance, depending on the processing parameters, was found to be between 5% and 10% RSD for 5% w/w active pharmaceutical ingredient (API), and
Application of a Synthetic Listeriolysin O Gene Probe to the Identification of β-Hemolytic Listeria monocytogenes in Retail Ground Beef.

The synthetic gene probe is a 20 mer oligonucleotide, derived from listeriolysin O gene sequence of Listeria monocytogenes and shown to be specific for strains of this organism. This probe was used in a DNA-colony hybridization assay to evaluate its suitability in detecting (β-hemolytic L. monocytogenes in ground beef. Thirty-six ground beef samples were plated onto three media: Trypticase soy agar with 0.6% yeast extract, lithium chloride-phenylethanol-moxalactam agar and Martin's agar, both directly and after selective enrichment in Food and Drug Administration broth. Of the 118 gram-positive and catalase-positive isolates selected from the plates, only 24 gave detectable hybridization signal with the probe. CAMP-test and standard biochemical tests also revealed that only these 24 probe positive isolates were (β-hemolytic L. monocytogenes . Of the 36 samples of ground beef, 6 were positive for Listeria spp., out of which 4 were L. monocytogenes .
Practical Implications of Non-Invasive MRI-Based Liver and Cardiac Iron Assessments in Children and Adults with Transfusion-Dependent Anemias.

BACKGROUND: MRI measures of hepatic iron content (HIC) in patients with transfusional iron overload correlate well with invasive liver biopsy- based HIC measures. HIC is the major component of, and a good surrogate for total body iron burden, and has been used worldwide as an index for chelation management [OlivieriB children ρ-0.061, p=0.73). We identified a subset of subjects (2/34 children (6%), 7/32 adults (23%)) with severely low cardiac T2* but HIC within target range for therapy (predicted HIC 60%) but abnormal T2*, at risk for cardiac disease. We observed a significant difference in LVEF in children with TM vs. SS (59.5 ± 3.9 vs. 64.3±3.6%, p=0.008), and also a less significant difference between these groups in mean T2* measures (TM 26.11±3.55, SS 34.76±2.12 msec p = 0.1136). CONCLUSION: We demonstrate that in children and adults with transfusional iron overload (and non-transfused thal intermedia), combined T2* cardiac and R2* hepatic iron determination detects a population with severe cardiac iron deposition without matched increased HIC. As MRI assessments of cardiac and liver iron become prevalent, prospective studies will be needed to understand the best ways to use these data for management.
The Enzymology of 2-Hydroxyglutarate, 2-Hydroxyglutaramate and 2-Hydroxysuccinamate and Their Relationship to Oncometabolites

Many enzymes make “mistakes”. Consequently, repair enzymes have evolved to correct these mistakes. For example, lactate dehydrogenase (LDH) and mitochondrial malate dehydrogenase (mMDH) slowly catalyze the reduction of 2-oxoglutarate (2-OG) to the oncometabolite l-2-hydroxyglutarate (l-2-HG). l-2-HG dehydrogenase corrects this error by converting l-2-HG to 2-OG. LDH also catalyzes the reduction of the oxo group of 2-oxoglutaramate (2-OGM; transamination product of l-glutamine). We show here that human glutamine synthetase (GS) catalyzes the amidation of the terminal carboxyl of both the l- and d- isomers of 2-HG. The reaction of 2-OGM with LDH and the reaction of l-2-HG with GS generate l-2-hydroxyglutaramate (l-2-HGM). We also show that l-2-HGM is a substrate of human ω-amidase. The product (l-2-HG) can then be converted to 2-OG by l-2-HG dehydrogenase. Previous work showed that 2-oxosuccinamate (2-OSM; transamination product of l-asparagine) is an excellent substrate of LDH. Finally, we also show that human ω-amidase converts the product of this reaction (i.e., l-2-hydroxysuccinamate; l-2-HSM) to l-malate. Thus, ω-amidase may act together with hydroxyglutarate dehydrogenases to repair certain “mistakes” of GS and LDH. The present findings suggest that non-productive pathways for nitrogen metabolism occur in mammalian tissues in vivo. Perturbations of these pathways may contribute to symptoms associated with hydroxyglutaric acidurias and to tumor progression. Finally, methods for the synthesis of l-2-HGM and l-2-HSM are described that should be useful in determining the roles of ω-amidase/4- and 5-C compounds in photorespiration in plants.
From Blocks to Text and Back: Programming Patterns in a Dual-Modality Environment

Blocks-based, graphical programming environments are increasingly becoming the way that novices are being introduced to the practice of programming and the field of computer science more broadly. An open question surrounding the use of such tools is how well they prepare learners for using more conventional text-based programming languages. In an effort to address this transition, new programming environments are providing support for both blocks-based and text-based programming. In this paper, we present findings from a study investigating how learners use a dual-modality environment where they can choose to work in either a blocks-based or text-based interface, moving between them as they choose. Our analysis investigates what modality learners choose to work in, and if and why they move from one representation to the other within a single project. We conclude with a discussion of design implications and future directions for this work. This work contributes to our understanding of the affordances of blocks-based programming environments and advances our knowledge on how best to utilize them.
Modeling Errors as Unknown Inputs

Abstract The problem of representing modeling errors in fault detection algorithms is discussed. It is argued that the usual approach of treating them as additive disturbances leads to too many unknown inputs to facilitate decoupling. The idea of combining uncertainties along the equation structure is also critiqued and it is shown that decoupling from these results in unwanted decoupling from faults as well. An alternative is then proposed which uses the concept of underlying parameters; it is free from the above problems but requires the on-line “design” of the residual generator.
Stromatolitic Humid Climate Carbonates: A Variety of Calcrete?

Abstract Calcrete–like, stromatolitic carbonates are common precipitates on bedrock surfaces in humid climates. Microtextures are similar to Stage I calcretes of the classification by Gile, et al. Laminae are thin and discontinuous. Carbonate microcrystals range from columnar to fibrous and display textures similar to speleothems. The deposits are rich in clastic inclusions weathered from local bedrock. Stromatolitic masses are commonly found on the depositional surface of many joints and bedding planes. Stromatolitic features accreting on bedding planes develop vertically up or down. Those forming on joint surfaces are elongated nearly at right angles to the fractures. Stromatolitic deposits commonly consist of alternating layers of carbonate, clastics and, apparently, organisms. Stable isotope signatures are characteristic of freshwater soil carbonates. Low magnesium calcite is the dominant carbonate mineral with aragonite restricted to deposits developed on dolomitic rocks. The abundance of these stromatolitic deposits in humid regions enforces the idea that early stage calcretes have a broad climatic distribution.
A Multivariate Stochastic Flood Analysis Using Entropy

The principle of maximum entropy (POME) was used to derive a multivariate stochastic model for flood analysis. By specifying appropriate constraints in terms of covariances, variances, and cross-covariances, multivariate Gaussian and exponential distributions were derived. As a special case, the bivariate process of flood peaks and volumes was investigated for three cases: (1) the peaks and volumes are independent and occur the same number of times; (2) the number of peaks is more than that of volumes in the same time interval; and (3) peaks and volumes exhibit dependence Special emphasis was given to the structure of the matrix to Language multipliers in the model. Marginal distributions of flood characteristics were obtained, first with no restrictions imposed, and then with assumptions of independent occurrences and a high threshold value. The conditional distribution of flood volume given the peak was then discussed.
Helping Students Learn About Electromagnetics [Book/Software Reviews]

The reviewer of the book "Conceptual Electromagnetics" notes that the book describes the fundamental subject of electromagnetics, or field and wave theory, for an undergraduate college class using very advanced teaching and learning methods. It provides abundant opportunities for instructors to introduce innovative lectures, in-class and homework assignments, and tests (including those for online distance education and for students pursuing independent learning). An active teaching and learning methodology is built into this text by means of interactive in-class questions, explorations, and discussions. The book also includes peer instruction, allowing students to tutor one another. The learner-centered pedagogies and practices - and active teaching and learning, in particular - are very effective, motivational, and positively evaluated by students. There are many conceptual questions as well as multiple-choice ones that focus on core concepts of the material, requiring conceptual reasoning and understanding. This book is organized into 12 chapters on electrostatics fields, steady electric currents, magnetostatic fields, time-varying electromagnetic fields, uniform plan electromagnetic waves, transmission lines, waveguides and cavity resonators, and antennas and wireless communication systems. For many engineering students, the fields and waves, or electromagnetics, course is particularly challenging. But, with the author' advanced teaching and learning approach, this course can be pleasant and fun. His teaching technique should become the standard for all science and engineering courses.
Manifolds and Varieties via Sheaves

In rough terms, a manifold is a “space” that looks locally like Euclidean space. An algebraic variety can be defined similarly as a “space” that looks locally like the zero set of a collection of polynomials. Point set topology alone would not be sufficient to capture this notion of space. These examples come with distinguished classes of functions (C ∞functions in the first case, and polynomials in the second), and we want these classes to be preserved under the above local identifications. Sheaf theory provides a natural language in which to make these ideas precise. A sheaf on a topological space X is essentially a distinguished class of functions, or things that behave like functions, on open subsets of X. The main requirement is that the condition to be distinguished be local, which means that it can be checked in a neighborhood of every point of X. For a sheaf of rings, we have an additional requirement, that the distinguished functions on \(U \subseteq X\) should form a commutative ring. With these definitions, the somewhat vague idea of a space can be replaced by the precise notion of a concrete ringed space, which consists of a topological space together with a sheaf of rings of functions. Both manifolds and varieties are concrete ringed spaces.