cssi/SciSciGPT-SciSciNet huggingface dataset:
Implications of Bond-Slip in Inelastic Dynamic Responses of Degrading Structural Systems

The influence of bond-slip behavior, shown by pinched hysteretic curves in the inelastic response of degrading structural systems, is investigated in this paper. Inelastic response spectra are calculated and compared for deteriorating structures with and without manifestation of bond-slip. The response spectra are generated by using a smooth hysteretic model with distinct degrading parameters that are calibrated to the generic inelastic envelopes. In addition to the ductility demands, degraded residual strengths and stiffness of structural systems after an earthquake are considered as the relevant response measures. These measures can serve as design parameters for structures that should remain functional after an extreme event. Based on the response spectra analyses, it is found that nonlinear responses of degrading structural systems with bond-slip develop larger ductility demands and greater loss of strength and stiffness than the responses without bond-slip. Numerical results show that, ductility demand is increased up to 25–100% with consideration of slip in the model, as well as residual strength and stiffness decreased up to almost half.
Program Control: Branching and Repetitive Calculations

The chapter begins with a discussion of Fortran 90’s implementation of program control constructs, including the IF…THEN… and CHOOSE… pseudocode commands and the LOOP…END LOOP pseudocode command. Fortran implementation of the relational operators and the LOGICAL data type is discussed.
Estimation of Physical Activity Intensity in Spinal Cord Injury Using a Wrist-Worn ActiGraph Monitor

Abstract Objectives To derive accelerometer count thresholds for classifying time spent in sedentary, light intensity, and moderate-to-vigorous physical activity (MVPA) in manual wheelchair users (MWUs) with spinal cord injury (SCI). Design Participants completed 18 activities of daily living and exercises for 10 minutes each with a 3-minute break between activities while wearing a COSMED K4b2 portable metabolic cart and an ActiGraph activity monitor on the dominant wrist. A linear regression was computed between the wrist acceleration vector magnitude and SCI metabolic equivalent of task (MET) for 80% of the participants to obtain thresholds for classifying different activity intensities, and the obtained thresholds were tested for accuracy on the remaining 20% of participants. This cross-validation process was iterated for 1000 times to evaluate the stability of the thresholds on data corresponding to different proportions of sedentary, light intensity, and MVPA. MET values of 1.5 or lower were classified as sedentary behavior, MET values between 1.5 and 3 were classified as light intensity, and MET values of 3 or higher were classified as MVPA. The final thresholds were then validated on an out-of-sample independent dataset. Participants MWUs (N=17) with SCI in the out-of-sample validation data set. Interventions Not applicable. Setting Research lab, community Main Outcome Measures Accelerometer thresholds to classify sedentary, light intensity, and MVPA were obtained and their accuracy tested using cross-validation and an out-of-sample dataset. Results The threshold between sedentary and light intensity was 2057 counts-per-minute, and the threshold between light intensity and MVPA was 11,551 counts per minute. Based on the out-of-sample validation, the obtained thresholds had an overall accuracy of 85.6%, with a sensitivity and specificity of 95.3% and 97.4% for sedentary behavior, 87.8% and 84.5% for light intensity, 68.5% and 96.3% for MVPA, respectively. Conclusion Accelerometer-based thresholds can be used to accurately identify sedentary behavior. However, thresholds may not provide accurate estimations of MVPA throughout the day when participants engage in more resistance-based activities.
Relationship Between State Preemption of Inclusionary Zoning Policies and Health Outcomes: Is There Disparate Impact Among People of Color?

This study examines the relationship between state preemption of inclusionary zoning policies and health outcomes among different demographic groups. Controlling for state- and individual-level con...
Analysing the global health agenda: A comparison of priority for diabetes and oral diseases.

Many claims are made concerning which issues are on the global health agenda and which are neglected. Scholarship is inconsistent and generally vague about how an issue’s status is (or should be) m...
From canonical to modified nucleotides: balancing translation and metabolism

Every type of nucleic acid in cells may undergo some kind of post-replicative or post-transcriptional chemical modification. Recent evidence has highlighted their importance in biology and their chemical complexity. In the following pages, we will describe new discoveries of modifications, with a focus on tRNA and mRNA. We will highlight current challenges and advances in modification detection and we will discuss how changes in nucleotide post-transcriptional modifications may affect cell homeostasis leading to malfunction. Although, RNA modifications prevail in all forms of life, the present review will focus on eukaryotic systems, where the great degree of intracellular compartmentalization provides barriers and filters for the level at which a given RNA is modified and will of course affect its fate and function. Additionally, although we will mention rRNA modification and modifications of the mRNA 5'-CAP structure, this will only be discussed in passing, as many substantive reviews have been written on these subjects. Here we will not spend much time describing all the possible modifications that have been observed; truly a daunting task. For reference, Bujnicki and coworkers have created MODOMICS, a useful repository for all types of modifications and their associated enzymes. Instead we will discuss a few examples, which illustrate our arguments on the connection of modifications, metabolism and ultimately translation. The fact remains, a full understanding of the long reach of nucleic acid modifications in cells requires both a global and targeted study of unprecedented scale, which at the moment may well be limited only by technology.
Performance issues in correlated branch prediction schemes

Accurate static branch prediction is the key to many techniques for exposing, enhancing, and exploiting Instruction Level Parallelism (ILP). The initial work on static correlated branch prediction (SCBP) demonstrated improvements in branch prediction accuracy, but did not address overall performance. In particular SCBP expands the size of executable programs, which negatively affects the performance of the instruction memory hierarchy. Using the profile information available under SCBP we can minimize these negative performance effects through the application of code layout and branch alignment techniques. We evaluate the performance effect of SCBP and these profile-driven optimizations on instruction cache misses, branch mispredictions, and branch misfetches for a number of recent processor implementations. We find that SCBP improves performance over (traditional) per-branch static profile prediction. We also find that SCBP improves the performance benefits gained from branch alignment. As expected, SCBP gives larger benefits on machine organizations with high mispredict/misfetch penalties and low cache miss penalties. Finally, we find that the application of profile-driven code layout and branch alignment techniques (without SCBP) can improve the performance of the dynamic correlated branch prediction techniques.
Nonparametric Approximation Methods for the First-Passage Time Distribution for Degradation Data Measured with Unequal Time Intervals

Evaluating the first-passage time (FPT) distribution of a stochastic process is a prominent statistical problem, which has long been studied. This problem has important applications in reliability and degradation data analysis since the time that a degradation process of a product passes a critical level is considered as the failure time of the product. While most of the studies for FPT distribution focus on parametric stochastic process in the past, nonparametric approaches based on empirical saddlepoint approximation (ESA) are proposed recently. An advantage of those nonparametric approaches for evaluating the FPT distribution is that it does not require the specification of the parametric form of the underlying stochastic process. However, those nonparametric approaches based on ESA require the degradation measurements to be measured at equally distanced time points. For this reason, several random imputation methods are proposed by Palayangoda et al. (Appl Stoch Model Bus Ind 36(4):730–753, 2020). To facilitate the ESA method when the degradation data are measured at unequal time intervals, in this chapter, a least-squares modeling approach is proposed as an alternative approach to the random imputation methods. Monte Carlo simulation studies are used to evaluate the performance of the proposed methods for estimating the quantiles of the FPT distribution and for estimating the standard deviation of the FPT. Finally, degradation data analysis of a laser data is used to illustrate the methodologies presented in this chapter.
A Quantitative Comparison of Heavy Metal Concentrations in the Soils on Two Rocky Mountain West tribal Reservations

Native Americans have experienced a long history of environmental injustice, including natural resource exploitation and commercial activity with environmental impacts. A community-based participatory research (CBPR) approach was used to partner with two Rocky Mountain West reservations to conduct pilot-level assessments of potential soil contamination by heavy metals. The Community Advisory Board in conjunction with the research team selected residential areas and community sites for sampling. Samples were obtained, transported to a laboratory for dehydration and sieving, and were analyzed with a handheld X-ray fluorescence (XRF) tool for the presence of 24 heavy metals. Heavy metals concentrations were compared between reservations and were found to be statistically different from one another. Findings were also compared to levels recommended by the Environmental Protection Agency (EPA) and World Health Organization (WHO) to determine possible hazards to human health. Concentration of Sr, Rb, and Th were well above acceptable EPA levels and require further analysis. High localized Pb levels were found in one area, while Hg levels were found close to EPA standards. CBPR was essential to understanding preliminary contamination patterns. In conclusion, even reservations with similar geographies and histories present with unique contaminations and require individualized study to determine possible environmental mitigation.
What Killed Your Plant? Profligate Omissions and Weak Centering

This paper is on the problem of profligate omissions. The problem is that counterfactual definitions of causation identify as a cause anything that could have prevented an effect but that did not actually occur, which is a highly counterintuitive result. Many solutions of this problem appeal to normative, epistemic, pragmatic, or metaphysical considerations. These existing solutions are in some sense substantive. In contrast, this paper concentrates on the semantics of counterfactuals. I propose to replace Strong Centering with Weak Centering. This allows that the actual world is not the only world that is closest to the actual world. As a result, some counterfactuals that would otherwise have been true, turn out to be false. When these counterfactuals concern causation, fewer causal claims are true. In addition to describing steps towards solving the problem of profligate omissions, the proposal captures an abstraction that is shared by many of the existing solutions: depending on how the distance ordering underlying the Weak Centering condition is constructed and interpreted, some of these existing solutions can be recovered.
Elucidating energetics and kinetics in environmentally relevant mixed gas plasmas

Understanding energy distributions and kinetic processes in low temperature plasmas is vital to increase their utility for a range of applications, in particular pollution remediation. Optical emission spectroscopy (OES) was employed to elucidate energetic and kinetic trends for several diatomic species in CH4/N2 and CH4/H2O plasma systems. Vast differences in rotational and vibrational temperatures between dissimilar plasma species were observed, indicating the internal temperatures of excited state species are not equilibrated with each other. In combination with energy partitioning results, species formation and destruction rates within the plasma were derived from time-resolved OES data. The results provide insight into molecule formation pathways, including that the formation of CN may be related to excited nitrogen species available in CH4/N2 plasmas.
Bones of the Head and Neck

The skull consists of 23 bones including the hyoid bone: eight paired bones (temporal, zygomatic, parietal, maxillary, nasal, lacrimal and palatine bones, and inferior nasal concha) and seven unpaired bones (occipital, frontal, sphenoid, ethmoid, and hyoid, mandible, and vomer). The vomer and inferior nasal concha are within the nasal cavity. Three foramina (or notches) of the face, e.g., supraorbital, infraorbital, and mental foramina, are usually observed from an anterior view. A number of structures exist at the skull base as well as the cranial fossae, which allows vessels and nerves to leave and enter the skull and also acts as the attachment of many skeletal muscles.
Gastric and Other Visceral Stimulation for Chronic Painful Gastrointestinal Motility Disorders

Abdominal pain is one of major complaints in functional gastrointestinal diseases (FGIDs). The pathophysiological mechanisms include visceral hypersensitivity, motility abnormalities, autonomic dysfunctions, central nerve system dysfunctions, etc. Gastrointestinal (GI) electrical stimulation has been introduced as a possible treatment for gastrointestinal motor-sensory dysfunctions. The Enterra Therapy, approved by FDA as a humanitarian device, has been applied for treating nausea and vomiting in gastroparesis patients. Although spinal cord stimulation (SCS) is mainly used in the management of chronic neuropathic pain, it has recently been introduced to treat GI motility disorders and abdominal visceral pain.
The flux ejection dynamo with small diffusivity

A number of examples are worked out to illustrate the consequences of reverse flux ejection from the surface of a convective layer of conducting fluid. Generally the reverse flux ejection has the opposite effect of magnetic buoyancy, tending to bury the fields rather than bringing them through the surface. Even a weak flux ejection effect prevents the excape of magnetic field through the surface. Reverse flux ejection at the surface of an αω-dynamo profoundly alters the character of the solutions of the dynamo equations. Altogether, flux ejection serves to obscure the interpretation of magnetic observations. The outstanding problem now is to determine under what circumstances there exists cyclonic convection with rotations in excess of ±1/2π in the rising columns of fluid. Negative turbulent diffusion is expected to be a close companion of the flux ejection effect.
"We Don't Want Anybody Anybody Sent": The Death of Patronage Hiring in Chicago

Former Congressman, now federal judge, Abner Mikva tells the following story about how the Democratic Organization of Cook County, Illinois -- otherwise known as "the machine" -- reacted to his initial expression of interest in political involvement:The year I started law school, 1948, was the year that Douglas and Steven­ son were heading up the Democratic ticket in Illinois. I was all fired up from the Students for Douglas and Stevenson and passed this storefront, the 8th Ward Regular Democratic Organization. I came in and said I wanted to help. Dead silence. "Who sent you?" the committeeman said. I said, "Nobody." He said, "We don't want nobody nobody sent." Then he said, "We ain't got no jobs." I said, "I don't want a job." He said, "We don't want nobody that don't want a job."This interchange epitomizes the political culture of Chicago in the hey­ day of the machine: the machine did not want any participants over whom it did not hold the power associated with employment. Patronage was, quite simply, the fuel that ran the machine.It is therefore not surprising that this political setting gave rise to many of the landmark constitutional cases challenging patronage hiring and firing. One early case was brought against Richard Elrod, a Democrat, who was elected Sheriff of Cook County in 1970. In time-honored fashion, Elrod proceeded to replace many of the Republican employees of the sheriff's office with Democrats. In Elrod v. Burns, a suit by sev­eral of the discharged employees, the Supreme Court held that patronage dismissals were unconstitutional. In another early case, Shakman v. Democratic Organization of Cook County, disappointed independent candidates for office brought suit to prohibit governmental bodies from basing hiring and firing decisions on political grounds. Although eight­een years after the suit was filed the United States Court of Appeals for the Seventh Circuit would reverse its own prior decision and determine that the Shakman plaintiffs did not have standing, the suit first resulted in a consent decree banning political discrimination in employment in the City of Chicago.
Neurological dysfunction associated with postoperative cerebellar mutism.

Background and objectives. The postoperative cerebellar mutism syndrome (CMS) is an unique acute postoperative complication characterized by transient decrease in speech output (often mutism), apathy, irritability as well as global cerebellar dysfunction. As much as 25% of patients undergoing a resection of a cerebellar or IV ventricular tumor may develop such a syndrome. In this retrospective study we characterize the clinical features of the CMS and explore potential etiologic mechanisms. Methods. We conducted a retrospective analysis of medical records and imaging tests of 8 consecutive patients with the CMS identified through the database of the Children’s Hospital and Dana-Farber Cancer Institute, Boston, and compared with a control group of 8 unaffected children undergoing a comparable tumor resection. Results. In contrast to the control group, children in the affected group had marked decrease in speech output and comprehension, apathy and lack of initiative, inattention, persistent eye closure, flaccid hemiparesis and a severe global cerebellar dysfunction. Swallowing difficulties and bowel and bladder dysfunction were also observed. The median duration of the syndrome as judged by the persistence of the communication abnormalities was 4 weeks. The recovery was near complete with exception for a persistent global cerebellar dysfunction. A comparison of CT and MRI scans of children in both groups failed to identify distinguishing features. Conclusion. A surgical lesion of the midline cerebellum can cause a complex neurological dysfunction such as the CMS. Thus, we postulate that the cerebellum and its connections function as a ‘modulatory system’ in control of both motor and non-motor functions, including attention and language.
Electrochemistry of ferrocene in acetonitrile: Evidence for irreversible kinetic behavior due to passive film formation

Abstract : Montenegro and Pletcher have recently pointed out that measurement of the heterogeneous electron transfer rate constant of the ferrocene/ferrocenium couple at ultramicroelectrodes in acetonitrile solutions gives values that are several orders of magnitude larger than those measured at conventional electrodes. In addition, Bond et al. have pointed out that there is ambiguity in the interpretation of the electrochemical behavior of this couple in organic solvents. There are large discrepancies between the results from different workers on similar electrolyte/solvent systems which serves to show the difficulty in marking reliable measurements on this supposedly ideal electrochemical system. The situation is further confused since it has been proposed as a potential standard couple for non-aqueous electromechanical calibration. In his work on similar measurements on ferrocene/ferrocenium in acetonitrile at an ultramicroelectrode, Bond has discussed in detail several possible reasons for these discrepancies. Keywords: Reprints.
Resynthesis by Trypsin of the Cleaved Peptide Bond in Modified Soybean Trypsin Inhibitor

Abstract Trypsin-soybean trypsin inhibitor complex was prepared by mixing essentially equimolar quantities of modified (Arg-Ile bond broken) soybean trypsin inhibitor and trypsin at pH 8.0. The pH of the solution was then suddenly dropped to 2 by addition of strong acid, thus allowing the complex to dissociate. The soybean inhibitor was separated from this solution by ammonium sulfate precipitation. This inhibitor was then allowed to react with trypsin at pH 3.75 and the time course of proton release was recorded. An "overshoot" was observed. This indicates that the inhibitor was predominantly virgin (Arg-Ile bond intact). Since the virgin inhibitor is thermodynamically unstable with respect to the modified inhibitor, the resynthesis of the reactive site peptide bond was achieved by kinetic control.
Spectral and Spatial Proximity-Based Manifold Alignment for Multitemporal Hyperspectral Image Classification

Multitemporal hyperspectral images provide valuable information for a wide range of applications related to supervised classification, including long-term environmental monitoring and land cover change detection. However, the required ground reference data are time-consuming and expensive to acquire, motivating researchers to investigate options for reusing limited training data for classification of other temporal images. Current studies that address high dimensionality and nonstationarity inherent in temporal hyperspectral data for classification are limited for the case where significant spectral drift exists between images. In this paper, we adapt and extend two manifold alignment (MA) methods for classification of multitemporal hyperspectral images in a common manifold space, assuming that the local geometries of two temporal spectral images are similar. The first method exploits a locally based manifold configuration of a source image (considered to be the “prior” manifold), and the second approach links local manifolds of two images using bridging pairs. In addition to exploiting manifolds estimated with spectral information for MA, we also demonstrate how spatial information can be incorporated into the MA methods. When evaluated using three Hyperion data sets, the proposed methods outperform four baseline approaches and two state-of-the-art domain adaptation methods. The advantages of the proposed MA methods are more evident when significant spectral drift exists between two temporal images. In addition to the promising classification results, the proposed methods establish a domain adaptation framework for analysis of temporal hyperspectral data based on data geometry.
The Metabolizable Energy Values and Digestibilities of Menhaden Fish Meal, Fish Solubles, and Fish Oils

Abstract Three energy balance experiments, using three-week-old male White Rock broilers, were conducted to determine the metabolizable energy (M.E.) content and the digestibility of the protein and the fat of ten menhaden fish meals, ten menhaden fish solubles and six menhaden fish oils. Results of Experiment 1 showed that the fish meal tested at three different levels of dietary inclusion had an average protein digestibility of 58.4% and a fat digestibility of 93.1% with no significant difference due to the levels of fish meal in the diet. The average M.E. value of the fish meals was 3.37 kcal./g. on a dry-matter basis, with a low coefficient of variation (5.6%), and 69.1% was metabolized. In Experiment 2 condensed fish solubles were determined to have protein and fat digestibilities of 57.1 and 88.7%, respectively. On the average, 70.4% of the energy in fish solubles was metabolized, and the M.E. content was 2.03 kcal./g., on an “as is” basis. The M.E. value had a coefficient of variation of 10.8%. This relatively high variation is probably due to the low levels of solubles incorporated in the test diets. The six oils tested had a fat digestibility of 90.6% and a M.E. value, on an “as is” basis, of 8.45 kcal./g. which was 89.9% of the gross energy.
The illustrated conversation

Collaboration-at-a-Glance is a program which provides a visual interface to an online conversation. Although the participants in the conversation may be at widely separate locations, the interface provides a visible shared electronic space for their interactions. The participants each have a first person view-point from which they can see who else is present and who is communicating with whom. In the first part of this paper, I describe the current implementation. In the second part of the paper, I discuss some of issues involved in expanding it to supplement an ongoing conversation with additional expressive information.
MK801 and amantadine exert different effects on subthalamic neuronal activity in a rodent model of Parkinson's disease

Efforts to develop adjuvant therapies for the treatment of Parkinson's disease (PD) have led to interest in drugs that could mimic the therapeutic effects of lesion or deep brain stimulation of the subthalamic nucleus (STN). Extracellular single unit recordings were conducted to determine whether noncompetitive NMDA receptor blockade, suggested to have potential as an adjuvant treatment in PD, attenuates rate increases and firing pattern changes observed in the STN in a rodent model of PD. Systemic administration of the noncompetitive NMDA antagonist MK801 to rats with unilateral dopamine cell lesions did not significantly alter burstiness or interspike interval coefficient of variation, although mean firing rate decreased by a modest 20% with 50% of neurons showing decreases in rate >15% and spike train power in the 3-8-Hz (theta) range was reduced. MK801, combined with the D1 dopamine agonist SKF 38393 in intact rats or administered alone in lesioned rats, also significantly reduced incidence of multisecond (2-60 s) periodic oscillatory activity. Amantadine, a drug currently used as an adjuvant agent in PD whose beneficial effects are commonly attributed to its noncompetitive NMDA antagonist properties, had effects that contrasted with those of MK801. In both intact and lesioned animals, amantadine significantly increased STN firing rates and total spike train power in the 8-50-Hz range and did not alter spike power in the 3-8-Hz range or multisecond oscillatory activity. These observations show that an effective noncompetitive NMDA antagonist such as MK801 induces modest change in STN activity in 6-hydroxydopamine (6-OHDA)-lesioned rats, with the most notable effect on multisecond periodicities in firing rate and theta frequency total spike power. Amantadine's effects differed from MK801's, raising questions about its primary mechanism of action and the role in PD pharmacotherapy of the STN rate increases induced by this drug.
Aging and the dendritic cell system: implications for cancer.

The immune system shows a decline in responsiveness to antigens both with aging, as well as in the presence of tumors. The malfunction of the immune system with age can be attributed to developmental and functional alterations in several cell populations. Previous studies have shown defects in humoral responses and abnormalities in T cell function in aged individuals, but have not distinguished between abnormalities in antigen presentation and intrinsic T cell or B cell defects in aged individuals. Dendritic cells (DC) play a pivotal role in regulating immune responses by presenting antigens to naive T lymphocytes, modulating Th1/Th2/Th3/Treg balance, producing numerous regulatory cytokines and chemokines, and modifying survival of immune effectors. DC are receiving increased attention due to their involvement in the immunobiology of tolerance and autoimmunity, as well as their potential role as biological adjuvants in tumor vaccines. Recent advances in the molecular and cell biology of different DC populations allow for addressing the issue of DC and aging both in rodents and humans. Since DC play a crucial role in initiating and regulating immune responses, it is reasonable to hypothesize that they are directly involved in altered antitumor immunity in aging. However, the results of studies focusing on DC in the elderly are conflicting. The present review summarizes the available human and experimental animal data on quantitative and qualitative alterations of DC in aging and discusses the potential role of the DC system in the increased incidence of cancer in the elderly.
A newly Proposed Classification of Epileptic Seizures. Neurophysiological Basis

SUMMARY Some aspects of the mechanisms that might be involved in the pathophysiology of seizure disorders are briefly mentioned and discussed on the basis of pertinent experimental data. This analysis was performed following the systematization of seizure types suggested in the recently proposed classification, while looking for possible pathophysiological bases that might apply to, and be compatible with the different seizure groups which are identified in this classification. Specific seizure types, or even some of their particular features, have been selected for a relatively more detailed analysis and discussion at the expenses of others which have been dealt with rather superficially or totally ignored. This selection does not imply differences in the significance, but simply reflects personal interests and/or relative (in)competence for some of the topics in question. It would appear that, in spite of the wealth of experimental evidence, we are still far from understanding the actual mechanisms operating in most forms of seizure disorders. RESUME L'auteur passe brievement en revue et discute sur des bases experimentales quelques aspects des mecanismes susceptibles d'etre impliques dans la physiopathologie des crises epileptiques. Cette analyse est effectuee en suivant la systematisation des crises recemment proposee par le Comite Terminologique de la Ligue Internationale contre l'Epilepsie et cherche ainsi a mettre en evidence les bases physiopathologiques correspondant aux differents types de crises identifiees dans cette classification. Certains types de crises specifiques ou quelques uns de leurs aspects particuliers ont ete retenus pour une analyse et une discussion relativement plus detaillees, aux depens d'autres types qui ont ete envisages de facon plus superficielle ou ont ete entierement ignores. Il ne faut pas voir dans une telle selection des differences de signification mais seulement une preuve de l'interet personnel et-ou de la competence (ou incompetence) relative de l'auteur pour certains des aspects en cause. De toute facon il semble qu'en depit d'une abondance de donnees experimentales nous soyions encore loin de connaitre les mecanismes responsables de la plupart des crises epileptiques.
Robin sequence: changes in thinking leading to changes in patient care.

Abstract Robin sequence is now understood to be a grouping of clinical findings that does not represent a distinct multiple anomaly syndrome. Previously known as the “Pierre Robin syndrome,” this fairly common association of micrognathia with cleft palate and upper airway obstruction was initially thought to be a specific disease, and entire treatment regimens were established to deal with presumed problems. Until recently, the management of Robin has not been excellent and mortality has been high. It is only a better understanding of the basic mechanisms leading to this sequence that has resulted in better care. This article reviews the history of the delineation of Robin sequence and how the perception of Robin has led directly to management decisions.
SOME APPLICATIONS OF THEORY AND EXPERIMENT TO THE STUDY OF BEDDING GENESIS

SUMMARY The origin of many sedimentation units deposited in granular cohesionless materials can be rationally explained by utilizing the concept of the profile of equilibrium. This basic concept can be formally expressed in terms of the variables, or groups of variables, that characterize a sediment transport system. A change in one or more variables or a shift in local base level will generally cause a shift in the spatial position of the profile, resulting in either aggradation or degradation. As shown by flume experiments, the rate of shift of the profile is a critical factor in bedding genesis. A relatively large and rapid upward shift of the profile results in the deposition of a tabular or wedge-shaped unit of cross-bedding, i.e., a laboratory delta. On the other hand, a gradual upward shift of the profile results in the deposition of a sequence of horizontal bedding that is commonly associated with intercalations of ripple or dune cross-bedding. For the intermediate case of a moderately rapid shift of the profile, the depositional sequence includes trough units and poorly-defined tabular units of cross-bedding with numerous intercalations of horizontal bedding. The concept of the profile of equilibrium therefore provides a rationale for considering the depositional framework for sedimentary structures produced by current flow.
AGU receives Crystal Bridge Award

[1] On 23 June the San Francisco Travel Association presented AGU with its Crystal Bridge Award, given to honor major convention customers who bring outstanding events with significant impact to San Francisco, Calif. For the past 43 years, AGU has held its Fall Meeting in San Francisco; for the past 17 years the meeting has been at San Francisco's Moscone Center. AGU is the second recipient of the Crystal Bridge Award, which last year went to Oracle.
Function of the Type V Transforming Growth Factor β Receptor in Transforming Growth Factor β-induced Growth Inhibition of Mink Lung Epithelial Cells

The type V transforming growth factor β (TGF-β) is a 400-kDa nonproteoglycan membrane protein that co-expresses with the type I, type II, and type III TGF-β receptors in most cell types. The type V TGF-β receptor exhibits a Ser/Thr-specific protein kinase activity with distinct substrate specificity (Liu, Q., Huang, S. S., and Huang, J. (1994) J. Biol. Chem. 269, 9221–9226). In mink lung epithelial cells, the type V TGF-β receptor was found to form heterocomplexes with the type I TGF-β receptor by immunoprecipitation with antiserum to the type V TGF-β receptor after 125I-TGF-β affinity labeling or Trans35S-label metabolic labeling of the cells. The kinase activity of the type V TGF-β receptor was stimulated after treatment of mink lung epithelial cells with TGF-β. TGF-β stimulation resulted in the growth inhibition of wild-type mink lung epithelial cells and to a lesser extent of the type I and type II TGF-β receptor-defective mutants, although higher concentrations of TGF-β were required for the growth inhibition of these mutants. TGF-β was unable to induce growth inhibition in human colorectal carcinoma cells lacking the type V TGF-β receptor but expressing the type I and type II TGF-β receptors. These results suggest that the type V TGF-β receptor can mediate the TGF-β-induced growth inhibitory response in the absence of the type I or type II TGF-β receptor. These results also support the hypothesis that loss of the type V TGF-β receptor may contribute to the malignancy of certain carcinoma cells.
INFINITE BRANCHED CIRCLE PACKINGS AND DISCRETE COMPLEX POLYNOMIALS

In the last decade much research has been done on questions related to circle packings, which are collections of circles in the plane with prescribed patterns of tangencies encoded by simplicial 2-complexes. The interest in circle packings and their connections with analytic functions was initiated by W. Thurston in 1985 when he suggested a method for approximation of conformal mappings using circle packings [20]. This method was shown to work by B. Rodin & D. Sullivan [15] later that year (see also [17]). Since then several results have been published (for example, [3, 4, 5, 10, 11, 14]) which seem to indicate the possibility of creating a discrete analog of the theory of analytic functions via circle packings. However, most of these results deal with univalent circle packings, that is, genuine packings of circles. Influenced by the idea of [3] that circle packings might be used to construct discrete parallels of analytic functions, we started in [7] to investigate non-univalent circle packings, particularly branched packings. We introduced there the notion of discrete Blaschke products and proved a branched version of the finite Riemann mapping theorem (see [20, 15]). We feel though that to have a solid foundation for a circle packing analog of the theory of analytic functions one needs something more. Since complex polynomials form a fundamental and very important class of analytic functions, it is natural to try to establish circle packing counterparts of these mappings. This is exactly the main theme of our paper.
Colorimetric analysis with N, N-dimethyl-p-phenylenediamine of the uptake of intravenously injected horseradish peroxidase by various tissues of the rat.

1. A method is described for the colorimetric determination of peroxidase with N,N-dimethyl-p-phenylenediamine. The amount of red pigment formed by peroxidase is proportional to the concentration of enzyme and to the time of incubation during the first 40 to 90 seconds. The influence of the concentration of enzyme, N,N-dimethyl-p-phenylenediamine, H2O2, the time of incubation, pH, the temperature, and the possible interference by oxidizing and reducing agents of tissues has been tested. 2. The method has been used to follow the uptake of intravenously injected horseradish peroxidase by 18 different tissues of the rat over a period of 30 hours. The highest concentration of the injected tracer enzyme was found in extracts of kidney, liver, bone marrow, thymus, and spleen. Considerable amounts were taken up by pancreas, prostate, epididymis, and small intestine. Lower concentrations were found in extracts of lung, stomach, heart, and skeletal muscle, aorta, skin, and connective tissue. No uptake was observed by brain and peripheral nerve tissue. 3. Tissue homogenates containing high concentrations of the injected peroxidase, in general also showed high or average activity of acid phosphatase. 4. Six hours after intravenous administration, the liver contained 27 per cent, the kidney 12 per cent, and the spleen, 1.4 per cent of the injected dose. 5. Approximately 20 per cent of the injected peroxidase was excreted in the urine during the first 6 hours, and the concentration of peroxidase in blood serum and urine fell exponentially during this time. After 6 hours, only low concentrations were excreted in the urine but low enzyme activity was still detectable after 30 hours. Approximately 6 per cent of the injected dose was excreted in the feces from 6 to 20 hours after administration. 6. After feeding through a stomach tube, low concentrations of peroxidase were found in blood serum and urine. Considerable variations in the extent of absorption from the gastrointestinal tract were observed in individual rats.
Visible Chromophore Phosphines as Functional Elements of Luminescent Metallopolymers

A general modular route to fluorophore-linked diphosphines from (4-iodophenyl)P(O)Ph2 is described. The preparation of chromophoric diphosphine (LHP1) proceeded readily using this route. LHP1 was employed to prepare luminescent metallopolymers of platinum (P1) and palladium (P2) exhibiting modest degrees of polymerization (13−14) and extents of polymerization (∼97%). P1 and P2 appear to be the first metallopolymers polymerized via a visible-absorbing/emitting diphosphine. The photophysical properties of these novel materials are discussed.
Sex differences in the growth of the human bony pelvis.

The study of individual patterns of longitudinal growth of the bony pelvic complex reveals the following findings concerning the sex differences in the growth of the bony pelvis. (1) The patterns of growth show the same individual variability and male-female overlap as the adult configuration of pelves. (2) The sex differences in the adult bony pelvis cannot be attributed to the differential response of one bone to sex hormone. (3) Sex differences develop from complicated variations in rates and direction of growth of local areas of the pelvic complex. (4) The superior functional division of the bony pelvis shows only one notable sex difference — the sexual dimorphism of the directional growth of the anterior one-half of the iliac crest. (5) The inferior functional division of the bony pelvis shows numerous local areas of sexually dimorphic growth, but the major sex differences result from the greater lateral migration of the ischia. (6) Of the regions showing definite sexual dimorphism in growth, the pelvic inlet and sciatic notch are the more variable because of their dependency on two separate anatomical systems for their final adult morphological configuration. The subpubic angle and length of the superior pubic ramus are directly associated with only one anatomical system, the enlargement of the pelvic cavity, thus, they show less variability and more definitive sex difference.
Reinventing the Research University for Public Service

If the research university were reinventedfor public service, what would it be? This article addresses several such ques-tions and some of the intellectual and institutional issues they raise at a ...
The influence of gaseous environments on fatigue crack growth in a nickel-copper alloy

Cyclic crack propagation rates for a 65 pct nickel-33 pct copper alloy in low pressure, 0.013 MPa (100 torr), environments of hydrogen, oxygen, and nitrogen gas were compared to a reference crack propagation rate in a 1.3µPa vacuum. Crack propagation rates were determined over a range of temperatures for vacuum and hydrogen gas at a constant cyclic stress intensity. Crack propagation in the gaseous environment results in an increased crack propagation rate compared to growth rates in vacuum and a unique fracture mor-phology for each environment. Parallel investigations using transmission electron microscopy showed a unique dislocation structure adjacent to the fracture surface corre-sponding to each fracture morphology and environment. Fracture modes were transgran-ular in vacuum and nitrogen gas, transgranular with crystallographically-oriented features in oxygen gas, and intergranular over a range of temperature in hydrogen. A mechanism is suggested to explain gaseous environmental effects based on dislocation-gas atom inter-action.
Complexity of RNA in developing oocytes of Drosophila melanogaster.

RNA was extracted from Drosophila egg chambers which had been separated into four size classes, and in addition from mature ovarian eggs. The RNAs were hybridized with a Drosophila single-copy DNA tracer. Egg chamber RNAs from all stages of oogenesis examined contained single-copy DNA transcripts equal in complexity to the RNA of the mature egg.
Why December 21 Is the Longest Day of the Year

How fundamental ideas from max-min theory explain the location of the extrema of the times of sunrise and sunset.
An analysis of spatial mobility of urban activities in downtown Denver

A much neglected area of inquiry in geography is the analysis of spatial processes. It seems necessary, therefore, to initiate more effort in this area by examining and modifying existing means of investigation, or suggesting new ones. Using downtown Denver as the study area, an investigation of the spatial pattern of five urban activities from 1947 to 1971, by applying a modification of an existing means of research, shows a general temporal trend that suggests the working of the spatial process of urban equifinality. It is necessary, however, to extend the investigation of the area to several more future time periods, or to conduct a comparison between this area with several other urban areas before a firmer conclusion can be derived.
Transport Properties of Hydroxide and Proton Conducting Membranes

Hydroxide anion conducting solid polymer membranes, also termed anion exchange membranes, are becoming important materials for electrochemical technology, and activity in this field, spurred by renewed interest in alkaline fuel cells, is experiencing a resurgence. Solid polymer anion exchange membranes enable alkaline electrochemistry in devices such as fuel cells and electrolyzers and serve as a counterpoint to proton exchange membranes, of which there is a large body of literature. For their seeming importance, the details of transport in alkaline exchange membranes has not been explored thoroughly. In this work, a chloromethylated polymer with a polysulfone backbone was synthesized. 1H NMR spectroscopy was performed to determine the chloromethyl content and its position on the polymer structure. The chloromethylated polymer was solution cast to form clear, creasable films, and subsequent soaking of these films in aqueous trimethylamine gave benzyltrimethylammonium groups. The resulting anion exchange m...
Tolerance to amphetamine-induced impairment of rotarod performance in rats.

Acute administration of d-amphetamine sulfate (30 mg/kg, i.p.) caused muscle weakness and 80% failure in rotarod performance in rats. The incidence of performance failure progressively decreased to 30% in animals receiving d-amphetamine and tested daily for 8 days. A similar progressive reduction in performance impairment was observed in animals receiving d-amphetamine for 3,5, or 7 days (12.5%) and evaluated only once after the last dose. The tolerance is attributable to a physiological or biochemical rather than learning phenomenon.
Improved Oxidation Resistance of Silicon Nitride by Aluminum Implantation: II, Analysis and Optimization

In the preceding paper, it was shown that aluminum ion implantation significantly improves the oxidation resistance of Si{sub 3}N{sub 4} ceramics under the influence of sodium. Not only is the oxidation rate reduced by up to an order of magnitude, the phase and morphological characteristics of the oxides grown on aluminum-implanted samples are improved as well. The role of aluminum in negating the detrimental effect of sodium on the oxidation resistance of Si{sub 3}N{sub 4} ceramics can be interpreted on the basis of network modification of the oxide layers by sodium and aluminum cations. The degree of improvement in the oxidation resistance does not, however, necessarily increase with the aluminum concentration. A simple quantitative analysis is presented which correlates the optimum aluminum implant concentration and the sodium content in the gas phase for the optimization of the oxidation resistance of Si{sub 3}N{sub 4} ceramics.
A Kantian View of Space

How does the brain represent space? Is this representation entirely the result of learning from experience? In his Critique of Pure Reason , Immanuel Kant argued that there must be certain “a priori conditions” of cognition, which could not be derived from experience but must instead be given prior to it. His theory includes two “a priori pure forms” of space and of time, regarded as constraints of thought rather than results of investigation or experience ( 1 , 2 ). On pages 1576 and 1573 of this issue, Langston et al. ( 3 ) and Wills et al. ( 4 ) both refer to Kant's theory and report that critical components of the brain's spatial representation systems are already in place when an animal first encounters an extended environment. This supports the view that spatial representation indeed includes an innate component prior to experience.
Analysis of the D′ → A′ transition in BrF

Abstract The emission spectrum of BrF in the 3400–3600 A region is recorded and analysed for 79 Br 19 F and 81 Br 19 F. The transition is assigned as D′(2) → A′(2), in which D′ belongs to the lowest cluster of three ion-pair states, and A′ is the lowest excited valence state. The main spectroscopic constants are: R c ′ 2.66 A, ω c ′ = 308 cm −1 . R c ″ = 2.07 A, ω c ′ ≈ 390 cm −1 , and D c ″ 5200 cm −1 .