cssi/SciSciGPT-SciSciNet huggingface dataset:
Cyclic Diguanylate Regulates Virulence Factor Genes via Multiple Riboswitches in Clostridium difficile.

ABSTRACT The intracellular signaling molecule cyclic diguanylate (c-di-GMP) regulates many processes in bacteria, with a central role in controlling the switch between motile and nonmotile lifestyles. Recent work has shown that in Clostridium difficile (also called Clostridioides difficile), c-di-GMP regulates swimming and surface motility, biofilm formation, toxin production, and intestinal colonization. In this study, we determined the transcriptional regulon of c-di-GMP in C. difficile, employing overexpression of a diguanylate cyclase gene to artificially manipulate intracellular c-di-GMP. Consistent with prior work, c-di-GMP regulated the expression of genes involved in swimming and surface motility. c-di-GMP also affected the expression of multiple genes encoding cell envelope proteins, several of which affected biofilm formation in vitro. A substantial proportion of the c-di-GMP regulon appears to be controlled either directly or indirectly via riboswitches. We confirmed the functionality of 11 c-di-GMP riboswitches, demonstrating their effects on downstream gene expression independent of the upstream promoters. The class I riboswitches uniformly functioned as “off” switches in response to c-di-GMP, while class II riboswitches acted as “on” switches. Transcriptional analyses of genes 3′ of c-di-GMP riboswitches over a broad range of c-di-GMP levels showed that relatively modest changes in c-di-GMP levels are capable of altering gene transcription, with concomitant effects on microbial behavior. This work expands the known c-di-GMP signaling network in C. difficile and emphasizes the role of the riboswitches in controlling known and putative virulence factors in C. difficile. IMPORTANCE In Clostridium difficile, the signaling molecule c-di-GMP regulates multiple processes affecting its ability to cause disease, including swimming and surface motility, biofilm formation, toxin production, and intestinal colonization. In this study, we used RNA-seq to define the transcriptional regulon of c-di-GMP in C. difficile. Many new targets of c-di-GMP regulation were identified, including multiple putative colonization factors. Transcriptional analyses revealed a prominent role for riboswitches in c-di-GMP signaling. Only a subset of the 16 previously predicted c-di-GMP riboswitches were functional in vivo and displayed potential variability in their response kinetics to c-di-GMP. This work underscores the importance of studying c-di-GMP riboswitches in a relevant biological context and highlights the role of the riboswitches in controlling gene expression in C. difficile.
Measurements of Composite Reflectors across Q-Band (33–50 GHz) and W-Band (75–115 GHz)

We present measured reflectivity of mirrors made of carbon fibre composite materials across Q-Band (33–50 GHz) and W-Band (75–115 GHz). High reflectivity is demonstrated and indicates that these composite reflectors are suitable for lownoise radio telescopes.
Proactive vs. reactive personalization: Can customization of privacy enhance user experience?

Abstract Online recommender systems have triggered widespread privacy concerns due to their reliance on personal user data for providing personalized services. To address these concerns, some systems have started allowing users to express their preferences before receiving personalized content (i.e., reactive personalization) rather than automatically pushing it to them (i.e., proactive personalization). However, this would mean constant calls for user action, which can adversely affect user experience. One potential solution is to offer users the ability to customize their privacy settings at the outset, thus obviating the need for constant consultation. We conducted a 2 (Personalization: Reactive vs. Proactive) X 3 (Customization of Settings: Absence vs. Action vs. Cue) factorial experiment (N = 299) with a movie recommendation system. Findings show that interface cues suggesting customization enhance user experience, even in the presence of proactive personalization. They also highlight the important role played by negative privacy experiences in the past.
A Review of Feature Reduction Methods for QSAR-Based Toxicity Prediction

Thousands of molecular descriptors (1D to 4D) can be generated and used as features to model quantitative structure–activity or toxicity relationship (QSAR or QSTR) for chemical toxicity prediction. This often results in models that suffer from the “curse of dimensionality”, a problem that can occur in machine learning practice when too many features are employed to train a model. Here we discuss different methods of eliminating redundant and irrelevant features to enhance prediction performance, increase interpretability, and reduce computational complexity. Several feature selection and extraction methods are summarized along with their strengths and shortcomings. We also highlight some commonly overlooked challenges such as algorithm instability and selection bias while offering possible solutions.
Powering Smart Homes with Information-Centric Networking

The growing trend of video traffic and ubiquitous Internet of Things applications have created substantial challenges for the host-centric communication model of today's Internet. As the major consumers of video applications and IoT devices, smart homes have become one of the critical components in the Internet ecosystem. In this article, we introduce a novel concept of intelligent and programmable home routers to power smart homes in the information-centric networking (ICN) architecture, which advocates a new content- centric communication paradigm for efficient content distribution and improved cybersecurity. The main features of the envisioned home ICN routers include at-edge cooperative caching for efficient content distributions, content modeling for security monitoring, and a delegation model of security operations between intelligent home ICN routers with resource-constrained IoT devices. The envisioned home ICN routers with much desired characteristics are a promising direction for addressing the rising challenges in operating, managing, and securing millions of smart home networks in the ICN architecture.
Comparison of clinical outcomes and automated performance metrics in robot-assisted radical prostatectomy with and without trainee involvement.

In this study, we investigate the effect of trainee involvement on surgical performance, as measured by automated performance metrics (APMs), and outcomes after robot-assisted radical prostatectomy (RARP). We compared APMs (instrument tracking, EndoWrist® articulation, and system events data) and clinical outcomes for cases with varying resident involvement. Four of 12 standardized RARP steps were designated critical (“cardinal”) steps. Comparison 1: cases where the attending surgeon performed all four cardinal steps (Group A) and cases where a trainee was involved in at least one cardinal step (Group B). Comparison 2, where Group A is split into Groups C and D: cases where attending performs the whole case (Group C) vs. cases where a trainee performed at least one non-cardinal step (Group D). Mann–Whitney U and Chi-squared tests were used for comparisons. Comparison 1 showed significant differences in APM profiles including camera movement time, third instrument usage, dominant instrument moving time, velocity, articulation, as well as non-dominant instrument moving time and articulation (all favoring Group A p < 0.05). There was a significant difference in re-admission rates (10.9% in Group A vs 0% in Group B, p < 0.02), but not for post-operative outcomes. Comparison 2 demonstrated a significant difference in dominant instrument articulation (p < 0.05) but not in post-operative outcomes. Trainee involvement in RARP is safe. The degree of trainee involvement does not significantly affect major clinical outcomes. APM profiles are less efficient when trainees perform at least one cardinal step but not during non-cardinal steps.
Burnout among medical and health sciences information professionals who support systematic reviews: an exploratory study.

Objective: The aim of this exploratory study was to assess personal, work-related, and client-related burnout among information professionals who support systematic review (SR) work. Methods: The Copenhagen Burnout Inventory, a validated tool for assessing burnout, was administered to information professionals who support SR work. A broad range of health sciences or medical librarians and information professionals were targeted via professional email discussion lists and news outlets. Questionnaire responses were captured electronically using Qualtrics Survey Software and quantitatively analyzed. Results: Respondents experienced an average personal burnout score of 48.6, work-related score of 46.4, and client-related score of 32.5 out of 100. Respondents who reported spending >80% of their job duties on SR work had significantly lower personal burnout scores than those who reported spending <10% of their job duties on SR work (average, 31.5 versus 50.9, respectively). Also, respondents who reported using an SR support tool had significantly lower personal burnout scores than those who reported sometimes using a tool (average, 43.7 versus 54.7, respectively). Conclusion: The results suggest that information professionals who dedicate more time to SR work or who consistently use an SR support tool experience less burnout. This study provides groundwork for further investigation with the aim of developing approaches to prevent or combat SR-related burnout among information professionals.
Weasel Words and the Analysis of “Postcommunist” Politics: A Symposium

A weasel word is a term used in academic or political discourse whose meaning is so imprecise or badly defined that it impedes the formulation of coherent thought on the subject to which it is appl...
Clinical effect of orthopedic-orthodontic treatment in crossbite in deciduous dentition

Objective To study the clinical effect of orthopedic-orthodontic treatment in crossbite in deciduous dentition through cephalmetric analysis. Methods 12 children with crossbite in deciduous dentition were enrolled in treatment group. Control group included 8 patients with normal deciduous dentition. Modified reverse headgear was used in each patient in the treatment group. Orthodontic force was a-bout 2. 94-4. 90 N (300-500 g) , and the direction of force was under occlusion plane for 37 degree. Each patient wore reverse headgear for 10 hour per day. Orthodontic treatment lasted for 6 months, and then orthodontic treatment began at once. Orthodontic treatment was not over until crossbite was corrected. The cephalmetric change was compared between two groups before treatment (T1) , after orthopedic treatment (T2)and after orthodontic treatment (T3). The effect of orthopedic-orthodontic treatment was analyzed in two group. Results Crossbite was corrected successfully in all patients in the treatment group. After treatment, A point moved forward by 2. 8mm, Is-FHp increased 8. 38 mm, ＜SNA increased 2. 65, incisors in mandible moved backward a little bit. All these changes were statistical different as compared with those in the control group. Conclusion Skeletal and dental deformity are improved progressively after combined orthopedic-orthodontic treatment. It is recommended to perform orthopedic-orthodontic therapy in skeletal crossbite in deciduous dentition. Key words: Orthopedic treatment; Orthodontic treatment; Reverse headgear; Crossbite in deciduous dentition
Novel use of XSTAT 30 for mitigation of lethal non-compressible torso hemorrhage in swine.

Background Management of Non-Compressible Torso Hemorrhage (NCTH) consists primarily of aortic occlusion which has significant adverse outcomes, including ischemia-reperfusion injury, in prolonged field care paradigms. One promising avenue for treatment is through use of RevMedx XSTAT 30™ (an FDA approved sponge-based dressing utilized for extremity wounds). We hypothesized that XSTAT 30™ would effectively mitigate NCTH during a prolonged pre-hospital period with correctable metabolic and physiologic derangements. Methods and findings Twenty-four male swine (53±2kg) were anesthetized, underwent line placement, and splenectomy. Animals then underwent laparoscopic transection of 70% of the left lobe of the liver with hemorrhage for a period of 10min. They were randomized into three groups: No intevention (CON), XSTAT 30™-Free Pellets (FP), and XSTAT 30™-Bagged Pellets (BP). Animals were observed for a pre-hospital period of 180min. At 180min, animals underwent damage control surgery (DCS), balanced blood product resuscitation and removal of pellets followed by an ICU period of 5 hours. Postoperative fluoroscopy was performed to identify remaining pellets or bags. Baseline physiologic and injury characteristics were similar. Survival rates were significantly higher in FP and BP (p<0.01) vs CON. DCS was significantly longer in FP in comparison to BP (p = 0.001). Two animals in the FP group had pellets discovered on fluoroscopy following DCS. There was no significant difference in blood product or pressor requirements between groups. End-ICU lactates trended to baseline in both FP and BP groups. Conclusions While these results are promising, further study will be required to better understand the role for XSTAT in the management of NCTH.
Predictors of Use and Outcomes of Mechanical Valve Replacement in the United States (2008-2017).

Background Contemporary nationwide data on the use, predictors, and outcomes of mechanical valve replacement in patients less than 70 years of age are limited. Methods and Results We identified hos...
Informed Pedagogy of the Holocaust: A Survey of Teachers Trained by Leading Holocaust Organisations in the United States

This chapter presents findings from a 2014 study of teachers who participated in one or more selective programmes to train teachers in Holocaust education and then returned to their classrooms to design and implement Holocaust instruction for students. The teachers were trained by at least one of three national organisations offering such programmes: the United States Holocaust Memorial Museum, the USC Shoah Foundation, and the Memorial Library. Teachers identified a range of factors that influence how they design and deliver Holocaust pedagogy in their classrooms, and given those factors, the pedagogical choices they make. The key factor that influences these teachers’ choices is their personal objectives and commitment, and their key pedagogical approach is literary or text-based. These findings can be instructional for both the individual teachers interested in such training and the organisations that train them.
Yeast Pyruvate Kinase: II. KINETIC PROPERTIES

The kinetic properties of purified yeast pyruvate kinase were investigated. The enzyme showed cooperative kinetics toward the essential activating monovalent cations K+ and NH4+, Mg2+, and phosphoenolpyruvate. Fructose 1,6-diphosphate, which yielded homotropic cooperative kinetics and did not affect maximal velocity, transformed the sigmoidal kinetics of K+ and NH4+, Mg2+, and phosphoenolpyruvate to hyperbolic and lowered the apparent Km for each variable. Adenosine diphosphate, however, exhibited no cooperativity and was relatively unaffected by fructose 1,6-diphosphate. The enzyme displayed a complex velocity dependence on pH.
Alkali Treatment of Cereal Grains. II. Digestion, Ruminal Measurements and Feedlot Performance

Two trials were conducted to determine the effects of feeding alkali-treated corn on various metabolic and performance characteristics of cattle. In the first trial, four ruminally-fistulated cows were fed high moisture corn (HMC) in the following forms: whole, rolled, sodium hydroxide (NaOH)-treated and ammonium hydroxide-treated. The corn was fed as 75% of the diet (dry matter basis) in four 15-day feeding periods in a 4 x 4 Latin square design. NaOH-treated HMC produced the highest dry matter digestibility (P less than .05), the highest rumen pH (P less than .05), the highest ruminal fiber digestion (P less than .05) and the highest fecal pH (P less than .05). Rolled HMC produced the lowest rumen pH (P less than .05) and lowest fiber digestion (P less than .05). Ammonium hydroxide-treated HMC produced no response in comparison to whole HMC and had the lowest rate of passage (P less than .05). Fecal starch, fecal water content, rumen fill and rumen ammonia were unaffected by treatments. In the second trial, 90 yearling steers were randomly allotted to five groups of 18 (six steers per pen). Steers were fed ad libitum a diet of 20% corn silage, 5% supplement and 75% corn as dry shelled corn, whole HMC, rolled HMC, NaOH-treated dry shelled corn or NaOH-treated HMC. There were no treatment effects on daily dry matter intake. Cattle fed either of the NaOH-treated corns had lower (P less than .05) average daily gains and poorer (P less than .05) feed efficiencies. No treatment effect was apparent for any carcass characteristic measured except yield grade, which was lower (P less than .05) for steers fed NaOH-treated HMC. Whole HMC produced the highest (P less than .05) fecal pH values while both NaOH treatments produced lower (P less than .05) fecal pH values than the other treatments.
Hypertension and Hematuria Secondary to Parapelvic Cyst

A parapelvic cyst is a well encapsulated collection of fluid outside of the renal parenchyma. It may give rise to urinary tract obstruction. Such a cyst at the renal pelvis may cause localized hydronephrosis, cortical thinning from intrarenal compression, and secondary hypertension remediable by surgical correction. However, to our knowledge, such a case has not been previously reported in the pediatric literature. CASE REPORT An 8-year-old black boy was evaluated for asymptomatic microscopic hematuria of six months9 duration. There was no history of renal or cardiovascular diseases or of hypertension in the family. Blood pressure, which was 100/60 mm Hg initially, rose to 140/94 mm Hg at six-month follow-up visit.
Changes and problematic areas in interpretation of the AJCC Cancer Staging Manual, 6th Edition, for breast cancer.

Abstract Context.—Tumor stage is an important prognostic factor and guides therapy for patients with breast cancer. The American Joint Committee on Cancer (AJCC) periodically updates the staging standards. This article describes changes and problematic areas in interpretation of the AJCC Cancer Staging Manual, 6th edition, for breast cancer and provides practical advice. Objectives.—This article reviews the variety of practical problems that can arise during assessment of the pathologic stage and other prognostic/predictive factors included in the College of American Pathologists Checklist for Evaluation of Resected Breast Cancers. Potential practical difficulties that can arise include the classification of lymph nodes, for example, isolated tumor cells, micrometastases, metastases, and the combination of locations. Another difficult area is assignment of a correct size. The use of clinical and imaging studies for optimal pathologic staging is discussed. Finally, the proper use of the TNM descriptors is ...
The effect of coke deposition on the deactivation of sulfated zirconia catalysts

Abstract The formation of coke on sulfated zirconia during the isomerization of n -butane was quantified as a function of time on stream and temperature. The formation of coke was essentially linear with time on stream when the isomerization reaction was performed at 200°C. When the amount of coke deposited reached 0.04 wt.%, the catalytic isomerization activity was observed to decrease to 10% of its initial value. When the reaction temperature was increased, the higher selectivity to cracked products resulted in an increase in coke formation and a higher rate of deactivation. The deactivated sulfated zirconia catalyst could be completely regenerated in air at 450°C. The TGA/FT-IR technique used offers significant advantages over other methods of quantifying coke deposition.
A survey of US objections to the sea-bed mining provisions of the Law of the Sea Convention☆

Abstract The United States does not participate in the deliberations at the Preparatory Commission for the International Sea-Bed Authority. In 1982, with the opening for signature of the United Nations Convention on the Law of the Sea, the US decided that the Convention was significantly flawed and did not meet sufficiently its national needs. This paper is an effort to characterize the current US position on the regulation of deep sea-bed mining and to evaluate the issues precluding the full participation of the United States in PrepCom.
Ecology and Conservation of a Rare, Old-Growth-Associated Canopy Lichen in a Silvicultural Landscape

Abstract Nephroma occultum Wetm. is a rare, epiphytic lichen associated with old-growth forests of northwestern North America. We describe its distribution, abundance, and habitat within the managed landscape of a southwestern Oregon watershed. Because this species is found mainly in the canopy, we used direct canopy access (tree climbing) in combination with ground (litter) searches for our surveys. We recommend this dual approach when confident determination of presence or absence of a canopy species is needed. Our surveys confirm that N. occultum is a rare old-growth associate within the area of this study, the southernmost extension of its known range. It was both rare across the landscape and uncommon in our primary study site, a 500 yr old stand. It was most often found growing close to the trunk on branches of large Pseudotsuga menziesii, but its distribution was sporadic even within an old-growth stand. The scarcity of very old stands, in combination with the limited ability of this species to dis...
Allergic bronchopulmonary aspergillosis: Characterization of antibodies and results of treatment☆

Abstract Two antibodies, one skin sensitizing and the other precipitating, are thought to play important roles in the pathogenesis of the syndrome of allergic bronchopulmonary aspergillosis. Further characterization of the antibodies in this study reveals the ability of the skin-sensitizing antibody to passively transfer systemic sensitivity to the monkey and the classification of the precipitating antibody as an IgG immunoglobulin. Two patients with the syndrome of allergic bronchopulmonary aspergillosis were treated with oral corticosteroids and amphotericin B aerosol. The treatment resulted in marked improvement including clearing of pulmonary infiltrates, decrease in eosinophilia, weight gain, increase in vital capacity, eventual negative sputum culture for Aspergillus, and disappearance of precipitating antibody.
The decoupling of right-handed neutrinos in chiral lattice gauge theories

Abstract The decoupling of the right-handed fermion in the continuum limit is proved for a class of chiral lattice gauge theories for which the right-handed fermion transforms trivially under the gauge group. No tuning is necessary. The theorem follows from a new fermion shift symmetry.
On-Line Measurement Of Hot Rolling Steel Bar

A passive instrument for on-line measuring hot rolling steel bar has been developed. The instrument uses self emission of the hot steel bar to deside the profile of working piece. The instrument can measure the dimensions of the cross section of the high speed and high temperature steel bar on the production line. It can be used for real-time monitoring, evaluating, and controlling the quality of the products. Compared with other similar instrument, new instrument has following features: - Passive measurement for simplifying the structure; - Simultaneous dimension and position measurement for ensuring high accuracy; - Temperature measurement for compensating thermal error; - Solid state sensor array for raising reliability; - Special structure for running in hostile enviornment; All these features make it possible to realize accurate measurement in high temperature, high humidity, and high dusty circumstance. The paper will present and discuss relative problems in the design and construction of this instrument. A prototype has been made and a series analogue experiments have been carried out in the laboratory. Rolling shop running test approves that the instrument can accurately measure the hot rolling steel bar on the production line. The total error is less than 0.05 mm while the measuring rate is as high as 2000 samples per second.
Color-matched esophagus phantom for fluorescent imaging

We developed a stable, reproducible three-dimensional optical phantom for the evaluation of a wide-field endoscopic molecular imaging system. This phantom mimicked a human esophagus structure with flexibility to demonstrate body movements. At the same time, realistic visual appearance and diffuse spectral reflectance properties of the tissue were simulated by a color matching methodology. A photostable dye-in-polymer technology was applied to represent biomarker probed “hot-spot” locations. Furthermore, fluorescent target quantification of the phantom was demonstrated using a 1.2mm ultrathin scanning fiber endoscope with concurrent fluorescence-reflectance imaging.
Mechanisms of cardioprotection by lysophospholipids.

The lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphosphatidic acid (LPA) reduce mortality in hypoxic cardiac myocytes. S1P is also cardioprotective in both mouse and rat models of cardiac ischemia/reperfusion (I/R) injury. Although these results are consistent with prior work in other cell types, it is not known what signaling events are critical to cardioprotection, particularly with respect to ceramide and the preservation of mitochondrial function, which is essential for cardiac cell survival. Neither receptor regulation nor signaling has been studied during I/R in the heart with or without the application of S1P or LPA. The role of sphingosine kinase in I/R and in ischemic preconditioning (IPC) has not been defined, nor has the fate or function of S1P generated by this enzyme, particularly during preconditioning or I/R, been elucidated. Whether S1P infused systemically in animal models of myocardial infarction in which survival is an end-point will be hemodynamically tolerated has not been determined. If not, the substitution of agents such as the monosialoganglioside GM-1, which activates sphingosine kinase, or the development of alternative ligands for S1P receptors will be necessary. © 2004 Wiley-Liss, Inc.
Clarification About Occurrence of Complications During Liposuction

It has been brought to my attention that the language describing inadvertent intra-abdominal penetration may not be clear in my chapter “Liposuction” in Neligan’s Plastic Surgery textbook1 and in fact may be implying …
Laminar free convection in carbon dioxide near its critical point

Abstract An experimental investigation on laminar free convection from a heated vertical flat plate immersed in carbon dioxide near its critical point is described. The test space was viewed with a Zehnder-Mach interferometer, thus giving an instantaneous picture of the distribution of refractive index. Use of the Lorenz-Lorentz equation, and equilibrium property data enabled the temperature field to be inferred, permitting the calculation of the heat-transfer coefficient and the thermal conductivity of the fluid. Very low rates of heating were used, the temperature differences being of the order of 0.001-0.01 °C, so that the constant property situation was closely approximated. High values of the thermal conductivity and the heat-transfer coefficient were detected in the critical region, both parameters showing a dependence on the heat rate. An engineering correlation for the heat-transfer coefficient was developed. The critical Grashof number for transition from laminar to turbulent flow was shown to be a function of the Prandtl number for the tests considered.
Effect of Curd Deformation during Cheddaring on Characteristics of Cheddar Cheese

Abstract Extension and rapid flow of curd during cheddaring produced greater distortion of curd particles and a higher moisture content in the resulting cheese. Differences in curd deformation caused by cheddaring modifications diminished during milling, salting, and pressing, and had little effect on characteristics of the final cheese.
Attitude Stability Criteria for Dual Spin Spacecraft

Attitude stability eriteria are developed for "dual spin" spacecraft, which consist of two primary bodies capable of unlimited relative rotation about a common axis. Such vehieles, typified in existing hardware by the Orbiting Solar Observatory (OSO) satellites, have applicability to missions for which the simplicity, reliability, and longevity of spin stabilization combine with a requirement for unidirectional pointing of a component, such as an antenna or a solar panel. The utility of dual spin systems is substantially increased by the results of attitude stability analysis, which reveals the possibility of obtaining passive stable spin-axis attitude by spinning a vehicle about its axis of greatest or least inertia, providing only that an effective energy dissipation device is attaced to a counter-rotating platform which has greatly reduced "spin." This result is coutrary to common interpretation of the familiar "major axis spin" requirement for stability, according to which energy dissipation in a vchicle rotating about its axis of least inertia must produce instability. Stability eriteria are developed first by Routhian analysis of a system with energy dissipation capability in only one of the two primary bodies, and subsequently in more general (but less rigorous) terms for a fully dissipative vehiele. Numerical integration and model studies provide corroboration.
Topical acetylcholine applications: Electrocortical-behavioral correlations

Abstract The electrophysiological and behavioral responses of chronically cannulated squirrel monkeys were examined following the topical application of acetylcholine to the cerebral cortex. Several combinations of spike and/or slow-wave patterns were observed. Gross behaviors (e.g. orientation) were little affected by the cortical paroxysmal discharges. Performance on a conditioned avoidance task utilizing a short CS-US interval was debilitated by the cortical discharges. On an avoidance task utilizing a longer CS-US interval only repetitive spike discharges produced a behavioral deficit. It was suggested that the cortical discharges are disruptive to motor and/or attentional processes which result in an increase in the time required to coordinate and emit the conditioned response.
Computer design of linear frequency selective networks

An efficient algorithm is proposed for the computer synthesis of linear networks of arbitrary configuration. Given a circuit approximately realizing a network function T(s), the element values are perturbed until T(s) is precisely realized. In the process, positive elements may be "grown" across nodes as required, or may be forced to desired values. Examples in the areas of passive and active filter design are given, and limitations of the procedure are discussed. Also, the method is shown to be related to the theory of equivalent networks.
Intrinsic mineral labeling of edible plants : methods and uses

The fate of minerals can be conveniently studied through intrinsic labeling techniques. The mineral of interest is biologically incorporated into the food in a form that can be distinguished analytically from the natural form of the element. Radiolabels have traditionally been used to study such problems as the uptake of minerals by plants, the gross and subcellular mineral distribution in plant tissues, the form and associations of the deposited mineral, and the bioavailability of minerals to animals and humans. The use of stable (nonradioactive) isotopes as a label offers the potential of safely studying bioavailability of minerals from individual foods in human population groups of all ages using foods processed in normal food handling and processing facilities.
Channel capacity limits for free-space optical links

Shannon's Channel Capacity has long been an elusive and merely theoretical goal, with real code structures and hardware implementations providing performance relatively far from the limit. With the somewhat recent advent of near-capacity-achieving codes, however, we can now actually use capacity calculations as practical metrics in optical link designs. In link budget calculations, we can explicitly show losses with respect to capacity that are directly traceable to engineering choices such as sub-optimum code rate selection, sub-optimum code structures, sub-optimum decoding architectures, and other effects. In this way, engineering elements of modulation and coding design can be compared equally with compromises in optics, tracking, and so on. We can further use capacity calculations to predict performance in fading channels, the bane of atmospheric and imperfectly tracked optical links. Such analysis suggests structures using coding and possibly interleaving that can get very close to the optimum performance. In fact, performance should be related to the average fade depth and not the deepest fades.
The Triterpenoid CDDO-Me Promotes Hematopoietic Progenitor Expansion and Myelopoiesis in Mice

The synthetic triterpenoid CDDO-Me has been shown to directly inhibit the growth of myeloid leukemias and lends itself to a wide array of therapeutic indications, including inflammatory conditions, because of its inhibition of NF-κB. We have previously demonstrated protection from acute graft-versus-host disease after CDDO-Me administration in an allogeneic bone marrow transplantation model. In the current study, we observed that CDDO-Me promoted myelopoiesis in both naive and transplanted mice. This effect was dose dependent, as high doses of CDDO-Me inhibited myeloid growth in vitro. All lineages (granulocyte macrophage colony-forming unit, BFU-E) were promoted by CDDO-Me. We then compared the effects with granulocyte colony-stimulating factor, a known inducer of myeloid expansion and mobilization from the bone marrow. Whereas both drugs induced terminal myeloid expansion in the spleen, peripheral blood, and bone marrow, granulocyte colony-stimulating factor only induced granulocyte macrophage colony-forming unit precursors in the spleen, while CDDO-Me increased these precursors in the spleen and bone marrow. After sublethal total-body irradiation, mice pretreated with CDDO-Me further displayed an accelerated recovery of myeloid progenitors and total nucleated cells in the spleen. A similar expansion of myeloid and myeloid progenitors was noted with CDDO-Me treatment after syngeneic bone marrow transplantation. Combined, these data suggest that CDDO-Me may be of use posttransplantation to accelerate myeloid recovery in addition to the prevention of graft-versus-host disease.
Matter wave lensing to picokelvin temperatures.

An optical dipole field is used as a collimating lens to cool Rubidium atoms to record-low kinetic temperatures of 50 picokelvin.
Distribution and translation of poliovirus RNA in guanidine-treated cells.

Abstract Guanidine (1.5 m M ) inhibits viral RNA synthesis more rapidly than viral protein synthesis in poliovirus-infected HeLa cells. Between 10 and 20 minutes following addition of guanidine at 3 hours 40 minutes after infection, the rate of viral RNA synthesis is reduced to 30% of that in untreated cells, whereas viral protein synthesis is still 70% of control. Viral RNA that is completed can be incorporated into viral polyribosomes and into mature virus particles in the presence of guanidine. This suggests that viral RNA molecules are released from the replication complex after completion. Moreover, no viral RNA is detected in the replication complex 10 minutes after addition of guanidine. As was shown previously for viral RNA synthesis, the inhibitory effect of guanidine on the rate of formation of infective virus diminishes rapidly when guanidine is added after the fourth hour in the viral growth cycle. The effect of guanidine on formation of infective virus may be secondary to inhibition of synthesis of viral RNA.
Variable Decision Strategies, Rational Choice, and Situation-Related Travel Demand:

Classical economic theory following Bentham and Mill assumes decision makers are completely informed, highly sensitive to differences between alternatives, and above all rational in being able to rank order the possible alternatives and choose among them on some measure of welfare (utility maximization). In recent years, this view has been successfully challenged by empirical studies of decision making, and many alternative decision rules have emerged (such as lexicographic, elimination by aspects, counting, conjunctive, heuristic additive difference, affective, take the best, and so on). Despite thirty years' work on boundedly rational and cognitive approaches, the classical view is still widely accepted in urban travel demand modeling. This paper develops a newer conceptual framework for shopping travel situations-namely, choice of shopping place on different kinds of tour, for different orders of goods, and for regional malls and neighborhood centers. Hypotheses concerning the use of different kinds of decision rule are generated for the different situations or contexts. A statistical design is provided for tests of these hypotheses using fieldwork, verbal protocol analysis, and low-level t-tests. Fifty-five MIT students are interviewed, and their protocols for the shopping situations recorded and analyzed. The findings are that decision rules are multiple and vary with context. Although the specific hypotheses of the paper are not strongly supported, there is overwhelming evidence of the widespread use of simple heuristics. Implications of the findings are drawn for future work in the travel demand field and the preference and choice field. In addition, the contribution of this paper to behavioral decision making is noted, through the extension of work on choice heuristics to a different field (travel demand) and the use of a fieldwork qualitative methodology.
Seismic evaluation and analysis of high-voltage substation disconnect switches

Disconnect switches are one of the components of an electrical substation that are vulnerable to the effects of earthquake shaking. Three vertical-break and two horizontal-break 230 kV switches of porcelain and composite construction were tested on a triaxial earthquake simulator in various configurations. Three-pole switches were mounted on a stiff, low-profile frame and tested according to the industry standard IEEE-693-1997. The vulnerable components of the switches were the aluminum spacers at the base of the switch posts and the welded post-blade connections and the bolted connections at the base of the posts. Single-degree-of-freedom models of the switch insulator posts were developed using experimental data to establish the amplification of seismic demand on the switches when mounted on frames of different heights and stiffness.
HIV/AIDS Teaching Behaviors of Educators in Haiti

Abstract This study examined the predictive power of knowledge, attitudes, support for AIDS education, teaching comfort, perceived behavioral control, religious (Vodoun and Christian) beliefs, and subjective norms on Haitian educators' teaching of HIV/AIDS to their students. Two hundred and fourteen teachers from Jeremie and surrounding areas in Haiti completed an anonymous questionnaire that included demographic questions, open-ended questions and eight scales. Four variables (subjective norms, perceived behavioral control, religious beliefs, and participant gender) were found to be significant predictors of HIV/AIDS teaching behavior. A binary logistic regression model was developed and correctly categorized 73% of those who did and did not teach about HIV to their students. Responses to open-ended questions supported and extended findings from the quantitative analyses.
The large and the small – who exploits whom?

Abstract This paper shows that, under some suitable conditions, a small individual – one who obtains a smaller share of the benefit of a common good, has a greater incentive to supply the common good than a larger individual.
Stress analysis of brittle spheres under multiaxial loading

Abstract An analytical method has been developed to determine the state of three-dimensional stresses in a sphere subjected to multiple contact loads. The method has been used to study the stress distribution in a sphere under a variety of loading conditions important to particulate systems. It is found that in the case of three-point in-plane loading the maximum tensile stresses are larger than that in uniaxial compression. As the number of contact points increases, the maximum internal tensile stress, in general, decreases as the state of stress inside the sphere approaches hydrostatic compression. The method was used to analyze the stresses in some tests carried out on glass and alumina spheres. The stress analysis indicates that the maximum contact stress and hence the tensile stress outside the contact circle correlate well with failure and are partially responsible for attrition in particulate systems.
Resonance Raman spectroscopic studies of hydroperoxo-myoglobin at cryogenic temperatures.

In agreement with previous reports (Gasyna, Z. FEBS Lett. 1979, 106, 213−218 and Leibl, W.; Nitschke, W.; Huettermann, J. Biochim. Biophys. Acta 1986, 870, 20−30) radiolytically reduced samples of oxygenated myoglobin at cryogenic temperatures have been shown by optical absorption and EPR studies to produce directly the peroxo-bound myoglobin at 77 K. Annealing to temperatures near 185 K induces proton transfer, resulting in the formation of the hydroperoxo heme derivative. Resonance Raman studies of the annealed samples has permitted, for the first time, the direct observation of the key ν(Fe−O) stretching mode of the physiologically important Fe-OOH fragment of this ubiquitous intermediate. The assignment of this mode to a feature appearing at 617 cm-1 is strongly supported by documentation of a 25 cm-1 shift to lower energy upon substitution with 18O2 and by a 5 cm-1 shift to lower energy for samples prepared in solutions of deuterated solvent.
Vickrey Auctions in Practice: From Nineteenth-Century Philately to Twenty-First-Century E-Commerce

William Vickrey (1961) proposed an auction mechanism in which bidders submit sealed bids, and the highest bidder wins the good in return for payment of the second-highest bid amount. For decades, economists have credited Vickrey with inventing this auction format, and have believed that the Vickrey auction is rarely used in practice. This paper presents evidence that Vickrey auctions have long been the predominant auction format for mail sales of collectible postage stamps. Stamp auctioneers developed this auction format on their own, as early as 1893, even before Vickrey was born.
Collateral projections from trigeminal sensory nuclei to ventrobasal thalamus and cerebellar cortex in rats

The retrograde fluorescent labeling technique reveals that trigeminal projections to the ventroposteromedial nucleus of the thalamus (VPM) of the rat originate from the main sensory nucleus (MSN) of the trigeminal and subnuclei interpolaris (V1) and caudalis (Vc) of the spinal trigeminal nucleus. These projections are predominantly contralateral; however, the presence of a few ipsilateral labeled cells in MSN suggests an uncrossed trigeminothalamic pathway. Trigeminocerebellar fibers projecting to the paramedian lobule (PML) of the cerebellar cortex are located in Vi and caudal subnucleus oralis (Vo). This is principally an ipsilateral pathway, but several bisbenzimide-labeled cells are present in contralateral Vi. The most notable finding occurred after paired injections of Evans Blue into VPM and bisbenzimide into PML, demonstrating neurons in Vi with divergent projections to both structures. The presence of this type of projection was not found in mice (Steindler: J. Comp. Neurol. 237:155-175, 1985) and has not been reported in other species.
The effect of cue familiarity on categorizing by preschool children

Two- and three-year-old children were administered a free-sorting task with familiar or unfamiliar forms and colors. We expected that children would be more likely to classify objects together when the objects matched in some way that was familiar to them. The results confirmed that expectancy. The results also indicated that experience with cues may override other factors, such as preference, in determining how a set of objects is sorted. We conclude that stimulus familiarity may be an important factor to consider in studies of the origins of children’s classification abilities.
The effects of price and cost uncertainty on investment

Abstract This paper examines the effects that increased uncertainty in future output prices, wage rates, and investment costs has on the quantity of investment undertaken by a firm. It is assumed that the firm maximizes the expected value of the sum of discounted cash flows, that the production function is homogeneous of degree one, and that there are increasing marginal costs to investment which vary randomly from period to period. The results are that so long as the non-negativity constraints are surely never binding, current investment does not decrease with increased uncertainty in future output prices and wage rates and is invariant to increased uncertainty in future investment costs.
Planning tool requirements for flexible manufacturing systems

Abstract Many flexible manufacturing systems (FMSs) are characterized to some extent by their capability (i.e., flexibility) for automatic tool changes. Therefore, many research issues are centered around tool-related prolems. However, the planning aspect of tool requirements has not been adequately addressed. Planning tool requirements for an FMS are parallel to planning capacity requirements in traditional manufacturing planning and control (MPC) systems. There is a rough-cut tool planning (RTP) problem at the higher level, while there is a detailed tool requirements planning (TRP) problem at the lower level. In this study, we integrate RTP and TRP decisions into the overall MPC system. Mathematical programs are formulated to represent the RTP and TRP problems. The interfaces between these planning activities and other subsystems are discussed and several implementation issues are identified.
“Think the sink:” Preliminary evaluation of a handwashing promotion campaign

Owing to its utility in guiding the planning and evaluation of health promotion campaigns, the Theory of Planned Behavior was used to implement a 1-month campaign aimed at increasing handwashing among college students. Based on observations of bathroom users' handwashing behavior (n = 1,005) and an online survey (n = 188), overall handwashing did not increase as a result of the campaign; however, more students did use soap (58% vs 70%). Future campaigns designed to increase handwashing behavior in students may be advised to target messages according to gender difference-based responsiveness to handwashing norms.
Taxes, Inflation, Speculation and the Cost of Homeownership*

This article formulates a measure of the cost of homeownership which accounts for (1) the tax subsidy to homeowning, (2) the element of expected inflation in mortgage interest rates and (3) speculation about appreciation in real house prices. Each component of the total cost of homeowning is estimated annually across the decade of the 1970s. Total real costs are found to have trended down during the period, primarily because of a decline in the real interest rate and increases both in the real tax subsidy and in expectations of real appreciation.