cssi/SciSciGPT-SciSciNet huggingface dataset:
Chapter 13 – Time- and Frequency-Domain Controls of Feedback Systems

This chapter is dedicated to the analysis and design of feedback control systems, as well as to defining, characterizing, and improving the performance of these systems in the time domain and in the frequency domain. The time domain is divided into the transient range and the steady-state range. Characteristics defining both sub-domains are formulated, and examples are used to illustrate these characteristics for first- and second-order systems. The root locus, as well as the time-domain solution, is utilized to model the time response of single-input, single-output (SISO) and multiple-input, multiple-output (MIMO) control systems. The frequency-domain response of SISO control systems is mostly modeled with the Bode plots by defining system characteristics pertaining to this domain. The connections between frequency- and time-domain performance qualifiers are formulated and studied here. This chapter also introduces notions of phase-lead and phase-lag compensator design in the frequency domain.
The everyday lives of older adults with visual impairment: An occupational perspective:

IntroductionIn order to live in a world created for the sighted, older adults with visual impairment must adapt to complete vision-dependent activities that require reading, writing, and object ide...
Substrate Specificity of Tissue Type Plasminogen Activator

In this chapter I will describe our recent studies designed to characterize and increase understanding of molecular determinants of the remarkably stringent substrate specificity of tissue-type plasminogen activator (t-PA). Ancillary to that discussion, however, is a very brief review of the standard terminology used to refer to specific subsites of a protease substrate1. The scissile bond is indicated by the arrow in Figure 1. Residues that are C-terminal of this bond are referred to as “primed” subsites, while those N-terminal of this bond are referred to as “unprimed” subsites. Each residue is also assigned a number based on its distance from the scissile bond. Residues forming the scissile bond are assigned the number “1”, adjacent residues are assigned “2”, and so forth, counting in both directions from the scissile bond. Each specific subsite, therefore, is uniquely identified by the assignment of a number and the designation as primed or unprimed.
Diagnosis and management of familial dyslipoproteinemia in children and adolescents.

CAD results from atherosclerosis, a chronic disease process that has its origin in childhood. Children and adolescents can be at higher risk for CAD by virtue of being from families with premature CAD or familial dyslipoproteinemias. The plasma lipid and lipoprotein levels result from a number of complex metabolic processes that are under the control of genetic and environmental (e.g., diet) influences. The normal ranges of plasma lipids and lipoproteins in children are known, and children and adolescents with dyslipoproteinemia are ordinarily defined as those having levels of plasma total, LDL, or triglyceride above the 95th percentile or with a low HDL cholesterol below the 5th percentile. Children of a parent with documented dyslipoproteinemia or with family history of premature CAD may be screened in the fasting state any time after 2 years of age. Following the exclusion of secondary causes of dyslipoproteinemia, the diagnosis of primary dyslipoproteinemia can be made. Lipoprotein patterns are not diagnostic for a given genotype. Efforts to determine further the biochemical defects responsible for a given phenotype have led to the investigation of gene coding for the apolipoproteins, the key enzymes in the lipoproteins pathways (LPL, HDL, and LCAT) and the receptors that process lipoproteins, such as the LDL receptor and the chylomicron remnant receptor. From a practical standpoint, the diagnosis of the kind of dyslipoproteinemia in a child will depend upon the nature and severity of the dyslipoproteinemia, both in the child (or adolescent) and in parents and siblings. Marked increases in plasma total and LDL cholesterol in the child and in at least one of the parents often reflect the presence of familial hypercholesterolemia, an inherited dominant condition due to a defect in the LDL receptor gene. The triglyceride levels are often normal. If the child has a different dyslipoproteinemia pattern from siblings and parents, then the diagnosis of familial combined hyperlipidemia or hyperapobetalipoproteinemia should be considered. Most children with mild or borderline elevations in total and LDL cholesterol will have polygenic hypercholesterolemia. Triglyceride problems in children and adolescents are relatively uncommon, particularly the more severe hypertriglyceridemia such as that found in lipoprotein lipase and apoC-II deficiency, dysbetalipoproteinemia, and type V hyperlipoproteinemia. High levels of Lp(a) lipoprotein, in isolation or in combination with other dyslipoproteinemia, accelerate risk for CAD. Low levels of HDL cholesterol in the absence of other abnormalities suggest the diagnosis of hypoalphalipoproteinemia.(ABSTRACT TRUNCATED AT 400 WORDS)
Canine Models of Narcolepsy

One of the major aims of the Stanford Sleep Research Center is to find the cause of human narcolepsy, a unique sleep disorder that affects 1 in 2000 of the general population. Since narcolepsy does not directly cause death, patients may ultimately pass away from an accident or illness, making the clinical-neuropathological correlation difficult to obtain from human subjects. Because of the nature and treatment of these accidents and unrelated illnesses patient specimens will generally not be available as uncontaminated neuropathological specimens of narcolepsy. The development of an animal model of narcolepsy was thus an urgent issue in the Stanford Sleep Research Center. In 1973, the Center had the extraordinary good fortune to acquire a female miniature French poodle who exhibited cataplexy and sleep onset rapid eye movement (REM) sleep periods (1). Active recruiting efforts resulted in the acquisition of additional narcoleptic dogs in small breeds, and finally in 1976, four narcoleptic Dobermans (two males and two females, including two litter mates) were obtained (2). With these multiple narcoleptic dogs, the Stanford Canine Narcolepsy Colony was established, and a breeding program was initiated (2).
Matrices with Rational Number Entries

In the definition of a linear substitution in Chapter 1, one can allow the multipliers to be rational numbers as well as integers. When this is done, the notion of a “linear substitution” is extended-what was called a linear substitution before is still a linear substitution, but new linear substitutions are allowed. The operation of composition of linear substitutions is defined in the same way as before, and it corresponds in the same way as before to an operation of matrix multiplication of matrices with rational entries.
Tuning Forkhead Box D3 overexpression to promote specific osteogenic differentiation of human embryonic stem cells while reducing pluripotency in a three‐dimensional culture system

Clinical use of human embryonic stem cells (hESCs) in bone regeneration applications requires that their osteogenic differentiation be highly controllable as well as time- and cost-effective. The main goals of the current work were thus (a) to assess whether overexpression of pluripotency regulator Forkhead Box D3 (FOXD3) can enhance the osteogenic commitment of hESCs seeded in three-dimensional (3D) scaffolds and (b) to evaluate if the degree of FOXD3 overexpression regulates the strength and specificity of hESC osteogenic commitment. In conducting these studies, an interpenetrating hydrogel network consisting of poly(ethylene glycol) diacrylate and collagen I was utilized as a 3D culture platform. Expression of osteogenic, chondrogenic, pluripotency, and germ layer markers by encapsulated hESCs was measured after 2 weeks of culture in osteogenic medium in the presence or absence doxycycline-induced FOXD3 transgene expression. Towards the first goal, FOXD3 overexpression initiated 24 hr prior to hESC encapsulation, relative to unstimulated controls, resulted in upregulation of osteogenic markers and enhanced calcium deposition, without promoting off-target effects. However, when initiation of FOXD3 overexpression was increased from 24 to 48 hr prior to encapsulation, hESC osteogenic commitment was not further enhanced and off-target effects were noted. Specifically, relative to 24-hr prestimulation, initiation of FOXD3 overexpression 48 hr prior to encapsulation yielded increased expression of pluripotency markers while reducing mesodermal but increasing endodermal germ layer marker expression. Combined, the current results indicate that the controlled overexpression of FOXD3 warrants further investigation as a mechanism to guide enhanced hESC osteogenic commitment.
Auditing Partisan Audience Bias within Google Search

There is a growing consensus that online platforms have a systematic influence on the democratic process. However, research beyond social media is limited. In this paper, we report the results of a mixed-methods algorithm audit of partisan audience bias and personalization within Google Search. Following Donald Trump's inauguration, we recruited 187 participants to complete a survey and install a browser extension that enabled us to collect Search Engine Results Pages (SERPs) from their computers. To quantify partisan audience bias, we developed a domain-level score by leveraging the sharing propensities of registered voters on a large Twitter panel. We found little evidence for the "filter bubble'' hypothesis. Instead, we found that results positioned toward the bottom of Google SERPs were more left-leaning than results positioned toward the top, and that the direction and magnitude of overall lean varied by search query, component type (e.g. "answer boxes"), and other factors. Utilizing rank-weighted metrics that we adapted from prior work, we also found that Google's rankings shifted the average lean of SERPs to the right of their unweighted average.
An Improved PWM Strategy for “SiC+Si” Three-Level Active Neutral Point Clamped Converter in High-Power High-Frequency Applications

In this paper, an improved pulse width modulation (PWM) strategy is introduced for three-level active neutral point clamped (ANPC) converters configured by Silicon Carbide (SiC) MOSFETs and Silicon (Si) IGBTs. Compared with the existing PWM strategies in the literature, this improved PWM strategy only interfaces with small commutation loops, therefore the turn-off voltage overshoots caused by the parasitic loop inductance are much lower. Soft switching is achieved across the IGBTs. Also, the conduction loss at zero voltage output is reduced due to the turn-on of two parallel conduction paths for zero voltage output. Furthermore, this proposed PWM strategy can protect the body diodes of the SiC MOSFETs from carrying large load current. To verify all these benefits of the improved PWM strategy, a megawatt (MW) scale three-phase three-level ANPC inverter is developed and implemented, and the experimental results are presented to verify the efficacy and merits of this improved PWM strategy.
Learning Nonlinearity of Microwave Imaging Through Deep Learning

The inherent presence of nonlinearity in microwave imaging makes the inversion problem challenging. To address this issue, we propose to use a machine learning method to learn the nonlinearity. In particular, a deep-learning based method is employed to correctly estimate the total electric field from an approximation that is generated by a Born-approximated solution. The learned total field is then used to estimate permittivity and conductivity. The applicability of our method is demonstrated for a 2D breast microwave imaging problem. The results show that the proposed method can predict the total electric field with high fidelity to the true total electric field and then can improve contrast recovery.
Collective Actuation

Modular robot designers confront inherent tradeoffs between size and power. Smaller, more numerous modules increase the adaptability of a given volume or mass of robot, allowing the aggregate robot to take on a wider variety of configurations, but do so at a cost of reducing the power and complexity budget of each module. Fewer, larger modules can incorporate more powerful actuators and stronger hinges, but at a cost of overspecializing the resulting robot in favor of corresponding uses. In this paper we describe a technique for coordinating the efforts of many tiny modules to achieve forces and movements larger than those possible for individual modules. In a broad sense, our work aims to make actuator capacity and range at least partly fungible by algorithm design and ensemble topology, rather than being immutable properties of a particular module design. An important aspect of this technique is its ability to bend complex and large-scale structures and to realize the equivalent of large-scale joints. By enabling scalable joints, and the “muscles” that could actuate larger structures, our work makes it more likely that modular robot ensembles can successfully be scaled up in number and down in size.
Exploring relationships between observed activation rates and functional attributes of lane departure prevention.

Objective: Drivers’ use of lane departure warning and prevention systems is lower than use of other crash avoidance technologies and varies significantly by manufacturer. One factor that may affect...
Plan U: Universal access to scientific and medical research via funder preprint mandates.

Preprint servers such as arXiv and bioRxiv represent a highly successful and relatively low cost mechanism for providing free access to research findings. By decoupling the dissemination of manuscripts from the much slower process of evaluation and certification by journals, preprints also significantly accelerate the pace of research itself by allowing other researchers to begin building on new results immediately. If all funding agencies were to mandate posting of preprints by grantees—an approach we term Plan U (for “universal”)—free access to the world’s scientific output for everyone would be achieved with minimal effort. Moreover, the existence of all articles as preprints would create a fertile environment for experimentation with new peer review and research evaluation initiatives, which would benefit from a reduced barrier to entry because hosting and archiving costs were already covered.
Two Forms of Fetishism: From the Commodity to Revolution in "Us"

This essay contends that Jordan Peele’s Us (2019) connects the psychic operation of fetishistic disavowal to the existence of class division. By exploring the role that fetishistic disavowal plays in commodity fetishism, the film makes clear how the psychic disposition of the ruling class perpetuates the suffering of an underclass that lives beneath the surface. Us reveals the connection between two forms of fetishism just as it reveals the inseparability of the psyche from politics. What separates Us from the typical Marxist critique of bourgeois individualism is the connection that it establishes between the psychic disposition of the individual and the social situation in which the individual exists. Without the necessary psychic response to the situation, class inequality would quickly become unsustainable. Through the nature of the revolt the film depicts, Peele attempts to illustrate how the psychic disorders of individuals ensconced within capitalist society make possible the sustained existence of its inegalitarian structure.
“It just doesn’t add up”: Disrupting official arguments for urban school closures with counterframes

Mass school closures have become commonplace in urban school districts. To explain their actions, school system leaders often rely on a dominant frame that presents closures as an inevitable, data-driven, and politically neutral phenomenon in an educational landscape defined by shrinking budgets, demographic changes, and increased school choice. In response, research has typically focused on how communities tell counternarratives that seek to interrupt official accounts of school closures. Using a critical frame analysis of qualitative data from the 2013 school closure process in Washington, DC, I discuss another grassroots approach to disrupting school closures: counterframes. Drawing on Critical Race Theory and social movement theory, I discuss counterframes as discursive arguments that allow communities to directly challenge official rhetoric and offer alternatives. Findings show that communities in DC crafted counterframes that pushed back on the notion that the closures were inevitable, questioned the data guiding the process, and attempted to expose hidden agendas and interests behind shuttering schools. The article concludes with the relevance of counterframes to broader educational mobilizations as well as their limitations.
Early Quantification of Systemic Inflammatory Proteins Predicts Long-Term Treatment Response to Tofacitinib and Etanercept

Abstract The application of machine learning to longitudinal gene-expression profiles has demonstrated potential to decrease the assessment gap, between biochemical determination and clinical manifestation, of a patient’s response to treatment. Although psoriasis is a proven testing ground for treatment-response prediction using transcriptomic data from clinically accessible skin biopsies, these biopsies are expensive, invasive, and challenging to obtain from certain body areas. Response prediction from blood biochemical measurements could be a cheaper, less invasive predictive platform. Longitudinal profiles for 92 inflammatory and 65 cardiovascular disease proteins were measured from the blood of psoriasis patients at baseline, and 4-weeks, following tofacitinib (janus kinase-signal transducer and activator of transcription-inhibitor) or etanercept (tumor necrosis factor-inhibitor) treatment, and predictive models were developed by applying machine-learning techniques such as bagging and ensembles. This data driven approach developed predictive models able to accurately predict the 12-week clinical endpoint for psoriasis following tofacitinib (area under the receiver operating characteristic curve [auROC] = 78%), or etanercept (auROC = 71%) treatment in a validation dataset, revealing a robust predictive protein signature including well-established psoriasis markers such as IL-17A and IL-17C, highlighting potential for biologically meaningful and clinically useful response predictions using blood protein data. Although most blood classifiers were outperformed by simple models trained using Psoriasis Area Severity Index scores, performance might be enhanced in future studies by measuring a wider variety of proteins.
Acute superior mesenteric venous thrombosis results in high rates of readmission and morbidity.

Abstract Objective Superior mesenteric venous thrombosis (MVT) is a poorly understood clinical entity, and as such, outcomes are poorly described. This study aimed to identify predictors of bowel ischemia after MVT and to compare outcomes for patients treated medically (group 1) with those for patients treated with bowel resection (group 2). Methods This was a retrospective, single-institution study capturing all patients diagnosed with symptomatic acute MVT on computed tomography imaging from 2008 to 2018. Demographics, comorbidities, imaging, laboratory values, and treatment were included. Predictors of bowel resection were analyzed by univariate and multivariate statistics. Outcomes including mortality, readmissions for abdominal pain, and chronic mesenteric venous congestion were compared using χ2 test. Results There were 121 patients included in the study; 98 patients were treated medically (group 1), 19 patients were treated with bowel resection (group 2), and 4 patients were treated with endovascular recanalization (group 3). Group 1 and group 2 were compared directly. Patients requiring bowel resection tended to have higher body mass index (P = .051) and a hypercoagulable disorder (P = .003). Patients who required bowel resection were more likely to present with lactic acidosis (P Conclusions A genetic hypercoagulable disorder is a predictor of bowel ischemia due to MVT. Regardless of treatment, outcomes after MVT are morbid, with high rates of readmission for abdominal pain. An alternative approach to treat these patients is needed, given the poor outcomes with current strategies.
Altering Routine Intensive Care Unit Practices to Support Commensalism

The gastrointestinal (GI) tract consists of trillions of organisms that support multiple functions in the body, from immunity, digestion, and absorption to drug metabolism. These microbes form an overall collection of microorganisms that form the body's microbiome. In critical illness, many of these functions are aberrant, and the microbiome is altered, leading to untoward effects. Some of the most common medications received by patients include antibiotics and proton pump inhibitors, which affect particular changes in the microbiome. In addition, patients receiving prolonged enteral and parenteral nutrition experience changes in the microbiological composition and diversity of their GI tracts. Research is ongoing to characterize the crosstalk between the microbiome and immune function as targets for drug and nutrition therapy.
Adversarial Attacks on Graph Neural Networks via Node Injections: A Hierarchical Reinforcement Learning Approach

Graph Neural Networks (GNN) offer the powerful approach to node classification in complex networks across many domains including social media, E-commerce, and FinTech. However, recent studies show that GNNs are vulnerable to attacks aimed at adversely impacting their node classification performance. Existing studies of adversarial attacks on GNN focus primarily on manipulating the connectivity between existing nodes, a task that requires greater effort on the part of the attacker in real-world applications. In contrast, it is much more expedient on the part of the attacker to inject adversarial nodes, e.g., fake profiles with forged links, into existing graphs so as to reduce the performance of the GNN in classifying existing nodes. Hence, we consider a novel form of node injection poisoning attacks on graph data. We model the key steps of a node injection attack, e.g., establishing links between the injected adversarial nodes and other nodes, choosing the label of an injected node, etc. by a Markov Decision Process. We propose a novel reinforcement learning method for Node Injection Poisoning Attacks (NIPA), to sequentially modify the labels and links of the injected nodes, without changing the connectivity between existing nodes. Specifically, we introduce a hierarchical Q-learning network to manipulate the labels of the adversarial nodes and their links with other nodes in the graph, and design an appropriate reward function to guide the reinforcement learning agent to reduce the node classification performance of GNN. The results of the experiments show that NIPA is consistently more effective than the baseline node injection attack methods for poisoning graph data on three benchmark datasets.
STANDARDS, SPECIFICATIONS, AND CODES: A UNION LIST APPROACH TO RESOURCE SHARING THE CHICAGO METROPOLITAN AREA

As a result of more sophisticated technology and a growing consumer pressure for product reliability, manufacturers, engineers, governmental representatives, and the general public alike are requiring improved access to standards and specifications. Traditionally, this information resource has been difficult to identify, to control, and to service. As a response to this problem, a small task force of Chicago area technical librarians conducted a survey of area users to ascertain what standards collections were available, what the level of need for standards might actually be, and the extent to which existing collections might be shared among users. The results of the survey were published by the Illinois Regional Library Council at Standards, Specifications and Codes Available in the Chicago Area: A Union List. (Chicago, IRLC, 1980.) In addition to the valuable data now available in the printed document, the project also served to encourage support for the concept of resource sharing among users in the lo...
Centering Minoritized Students in Campus Interpersonal Violence Research

Campus interpersonal violence - defined as sexual assault, sexual harassment, intimate partner violence, and stalking - is a social problem that has received widespread attention due to its high prevalence and devastating consequences, especially for students facing multiple forms of minoritization. Research on campus interpersonal violence prioritizes certain types of institutions; violence; victims, perpetrators, and bystanders; and intervention goals. This prioritization fails to challenge underlying systems of oppression and makes invisible minoritized students who are most affected by campus interpersonal violence. Historically, there has been an emphasis on acquaintance sexual assault against White heterosexual women at residential four-year predominantly White institutions. Far less studied are other types of violence and harm; violence experienced by gender and sexual minorities, and students of color; and students in online or commuter programs. In this commentary, we propose centering minoritized students to better situate campus interpersonal violence research within broader systems of oppression. We describe challenges to centering minoritized students in researching the problem, prevalence, and risk, as well as prevention and response interventions. We also provide recommendations for overcoming these barriers.
Women Artists and the Arte Útil Movements

Women artists are in the forefront of a major paradigm shift taking place in contemporary art as more and more artists are critically addressing the role of art and moving toward socially engaged, ...
Brief report: Musical improvisation skills can combat labile hypertension

Abstract Patients with labile hypertension experience transient but substantial increases in blood pressure, usually surrounding episodes of emotional distress and anxiety. Difficulties with or inability to express negative emotions may play a role. We hypothesize that therapy involving musical improvisation may blunt emotional response but may also decrease brain activity associated with negative thoughts and emotions. Unlike relaxation techniques that involve music, musical improvisation includes listening and creating music in a heightened state of awareness, listening and spontaneous interaction with music, and involves decreased activity in brain structures associated with negative thoughts and emotions. Improvisation experiences allow improvisers to predict and to anticipate what might occur in the moment, actively engaging in any unexpected “stress” that may come their way. (Palatini et al., 1998 Jul) To create and to improvise, musicians move past the anxiety of failure of being able to interact with unexpected stimuli, and we postulated that with a similar educational approach, patients may be able to better manage their labile hypertension.
Navigating social knowledge

Everyday phrases like ‘top dog’ and ‘low status’ suggest that we may mentally represent social and spatial information similarly. To what extent is that true? New research suggests that, like physical space, social knowledge is encoded as a cognitive map in the human brain and represented with a grid-like code.
Behind the Veil of Ambiguity: Decision-Making under Social and Non-Social Sources of Uncertainty

Research has long documented how different forms of uncertainty, namely risk and ambiguity, influence decision making. This literature, however, has given little attention to how decisions may differ in response to the source generating the uncertainty of potential outcomes. Some decisions may be social in nature where the uncertainty is generated by another person, whereas other decisions may be non-social involving uncertainty that is generated by probabilistic mechanisms. While past research has demonstrated the importance of source within the risk domain, our study provides the first exploration of social ambiguity sensitivity. We construct a general measurement of Social Uncertainty Sensitivity and explore how such sensitivity differs across three different uncertainty environments: risk, low ambiguity, high ambiguity. We find strong correlations between Social Uncertainty Sensitivity across levels of ambiguity and risk. Further, using reaction time as a proxy for information processing, we observe a significant relationship between Social Uncertainty Sensitivity and reaction time in decisions to invest (as opposed to not investing) in a given uncertainty environment. Our results demonstrate that not only is it important to consider the type of uncertainty environment on decision making, but that decisions are also shaped by individual sensitivity to how the uncertainty is derived.
The Domestic Policy Options

By 1986, the Japanese government was committed to the gradual implementation of the Maekawa Commission recommendations to internationalize the economy. Prime Minister Nakasone, banking on his influence generated by the overwhelming July 1986 electoral victory, forged ahead with his plans. Moreover, the underlying trends and changes in the economy were setting the stage for the implementation of the recommendations. At the same time, the govenment had no illusions about the difficulties that lay ahead. Its outlook was clouded by social and cultural traditions, economic policies based on narrow interests, its own fiscal austerity and the unclear impact of the yen’s rapid appreciation on the economy as a whole, at least in the short run.
THE FEASIBILITY OF A MACH 7 TRANSPORT EMPLOYING AIRBREATHING PROPULSION SYSTEMS.

Abstract : An extensive study of various propulsion and performance aspects of a single stage long range Mach 7 delta wing transport, 30,000 lb payload (125 passengers and cargo), was completed. The study encompasses consideration of the propulsive performance of a hypersonic ramjet design featuring lift augmentation. Particular attention is given to the influence of geometry, equivalence ratio, diffuser recovery characteristics, and boundary layer bleed on this performance. Considerable attention is given to climb and acceleration which is accomplished in two phases; a Mach 0-3.6 turbojet phase, and a Mach 3.6-7.0 ramjet phase. The significance of the number of turbojet engines, ramjet engine size, called-for tangential acceleration, and gross weight at take-off for trajectory characteristics, climb-time, climb-fuel and climb-range is presented. The results demonstrate that it is technically feasible to construct a hypersonic transport of intercontinental range. (Author)
Body signals during social play in free‐ranging rhesus macaques (Macaca mulatta): A systematic analysis

Social play involves one of the most sophisticated types of communication, that is, the use of play signals. Most primate research on play signals has focused on the use of the play face. However, some species appear to exhibit a variety of play signals. For example, rhesus monkeys (Macaca mulatta) have been reported to use body movements or postures that might have signal value during social play, in addition to the play face. However, it is not clear whether these body signals actually meet several criteria necessary to label them as “play signals.” Here we examine the forms and possible functions of seven candidate signals that we observed exclusively during social play contexts among free-ranging rhesus monkeys on Cayo Santiago. We aim to (1) distinguish them from actual play behavior (play involving contact or chasing) using loglinear analysis and (2) determine whether they predict playful behavior using modified PC-MC methods. Two candidate signals did not resemble any behaviors used in actual play. The other five signals contained elements that lasted longer or increased their conspicuousness over similar play behaviors, suggesting ritualized characteristics. Youngsters were likely to initiate contact or chasing play significantly sooner after candidate signals than in their absence. Thus, these candidate signals appear to meet critical criteria of signals that promote, moderate or facilitate play. As such, these findings open the door to questions about why multiple play signals have evolved. Am. J. Primatol. 76:168–179, 2014. © 2013 Wiley Periodicals, Inc.
A Conceptual Framework for Utilizing Black History Knowledge as a Path to Psychological Liberation for Black Youth

Several scholars suggest that Black history knowledge (BHK) is a significant psychological strength that facilitates mental health for Black people, and Black youth in particular, as they face raci...
Adaptive estimation and control of unstable periodic dynamics in excitable biological systems

Dynamical control of excitable biological systems is often complicated by the difficult and unreliable task of pre-control identification of unstable periodic orbits (UPOs). Here we show that, for both chaotic and nonchaotic systems, UPOs can be located, and their dynamics characterized, during control. Tracking of system nonstationarities emerges naturally from this approach. Such a method is potentially valuable for the control of excitable biological systems, for which pre-control UPO identification is often impractical and nonstationarities (natural or stimulation-induced) are common.
Further evidence for the selective disruption of intercellular communication by heptanol

The lack of selective gap junctional uncoupling agents has hampered evaluation of the contribution of intercellular communication to pharmacomechanical coupling and vascular contractility. Thus we ...
Depression and cancer survivorship: importance of coping self-efficacy in post-treatment survivors

Background An estimated 30% of cancer patients are expected to experience clinically significant psychological distress during the treatment phase of their disease. Despite significant attention being directed to the mental health needs of individuals undergoing and completing treatment, there is less known about the mental health needs of survivors and the role of potential protective factors in survivorship, such as coping self-efficacy and social support. Method One hundred and twenty-four post-treatment cancer survivors (mean age = 62.23 years, women = 70%, average 9.3 years post-treatment) were asked to complete measures of physical symptoms, coping self-efficacy, social support, and depression as part of a national convenience sample of cancer patients and survivors. Results About 20% of participants possessed scores on the Center for Epidemiologic Studies-Depressed Mood Scale indicative of clinically relevant depression. Coping self-efficacy was not only a significant predictor of depression (43% Variance Accounted For); it also partially mediated the relationship between symptoms and depression. Social support accounted for limited variance and was not a significant predictor of depression in a model containing both social support and coping self-efficacy as predictors. Conclusion A substantial minority of post-treatment survivors reported depression symptomatology. Coping self-efficacy may be an important component of patients' adjustment and possible target for intervention. These results highlight the ongoing mental health and support needs of cancer survivors. Copyright © 2012 John Wiley & Sons, Ltd.
Mobilizing piety: Islam and feminism in Indonesia

Rachel Rinaldo's book is a good example of how to study Muslim women and to avoid both orientalist stereotypes and many traditionalist Muslims’ uncritical apologetics regarding Islam and women.The ...
Meaningful Improvement in Perioperative Pain Control After Lumbar Surgery

As in other types of major musculoskeletal surgery, pain control following lumbar decompression and arthrodesis can be challenging. Parenteral narcotics, usually with a patient-controlled pump, remain the mainstay. While effective for most patients, there are substantial problems with this modality, including respiratory depression, nausea, emesis, and pruritus. Some patients, particularly those who are not opioid naive, have perioperative pain that is refractory to narcotic analgesia. There is long-standing interest in techniques to reduce our dependence on opioids. The report by Hyun Kang et al. is one of the latest in a long line of studies examining regional blocks to reduce the need for parenteral narcotics. This study has many strengths. It is randomized, double-blinded, prospective, and controlled. All patients had the same surgical procedures at the same institution, minimizing variation in the amount of surgical trauma. The study and control groups were statistically equivalent. The investigators demonstrated that a single dose of epidural ropivacaine reduced pain scores and fentanyl consumption two to twelve hours following surgery. The number of button pushes to deliver fentanyl was decreased at all but one time point up to forty-eight hours postoperatively. However, there was no difference between the two groups in terms of postoperative nausea and emesis, the length of hospitalization, or patient satisfaction. It should be noted that the study design was powered to discern the 2-point difference in pain at four hours. The study may be underpowered concerning these secondary but interesting parameters. …
Classification of Plant Somatic Embryos by Using Neural Network Classifiers

The development of somatic embryos is characterized by a series of morphological changes. Quantitative kinetic studies have been hampered by the difficulties in enumerating and characterizing embryo populations. By employing neural networks, we have developed a pattern-recognition system for characterizing the morphological features of carrot somatic embryos. This pattern-recognition system employs a hierarchical decision tree to achieve optimal classification. It successfully classified carrot somatic embryos into normal and abnormal embryo classes. For normal embryo classes (globular, oblong, heart, and torpedo embryos), an accuracy of 90% or higher was achieved. The features identified by the neural network classifiers as most important for embryo classification are almost identical to those obtained by the branch-and-bound searching algorithm used previously. However, employing the neural networks shortens the system developing time greatly. Coupled with an image analysis system, this neural-network-based pattern-recognition system shows great potential in embryo sorting and automation of synthetic seed production.
Slow-Binding Inhibition of γ-Aminobutyric Acid Aminotransferase by Hydrazine Analogues†,‡

(3-Hydroxybenzyl)hydrazine and methylhydrazine have been found to be potent slow-binding inhibitors of the pyridoxal 5-phosphate (PLP)-dependent enzyme gamma-aminobutyric acid aminotransferase (GABA-AT). Both compounds follow mechanism A (Morrison, J.F.; Walsh, C. T. Adv. Enzymol. 1988, 61, 201-301) which does not involve formation of a rapidly reversible enzyme-inhibitor complex before the formation of the final tight complex. The rate constant for formation of the enzyme-inhibitor complex determined from the slow-binding kinetics was 2.08 x 10(3) and 1.98 x 10(4) M-1 min-1 for methylhydrazine and (3-hydroxybenzyl)hydrazine, respectively. The rate constant for dissociation of the enzyme--inhibitor complex determined for the slow-binding kinetics was 4.6 x 10(-3) and 5 x 10(-3) min-1, respectively. The inhibition constants calculated from the slow-binding inhibition kinetics are 2.2 microM for methylhydrazine and 0.3 microM for (3-hydroxybenzyl)hydrazine. Reactivation of the inhibited enzyme was not first order, perhaps due to a side reaction of the hydrazine, but was consistent with the results obtained from the slow-binding kinetics. Inhibition constants were calculated from the level of enzyme activity at equilibrium inhibition. These constants are 2.8 and 0.46 microM for methylhydrazine and (3-hydroxybenzyl)hydrazine, respectively, in good agreement with those calculated from the slow-binding inhibition kinetics. 3-Hydrazinopropionate also behaved as a slow-binding inhibitor. However, the dependence of its kinetics on the concentration of inhibitor could not be described by the slow-binding or slow, tight-binding inhibition models. These kinetics could not be described by the tight-binding character of the inhibition because the addition of the competitive inhibitor propionic acid at 100 times its Ki did not affect the shape of the curve for inhibitor concentration dependence. The slow-binding inhibition appeared to require 2-4 molecules of 3-hydrazinopropionate/enzyme. The reactivation of enzyme inhibited by 3-hydrazinopropionate was first order with a rate constant of 6.9 x 10(-3) min-1. Its equilibrium inhibition constant was calculated to be < 20 nM. However, the inhibition constant calculated was dependent on the concentration of inhibitor because of the unusual character discussed above and may be much lower. Only 1 PLP/enzyme dimer reacted with methylhydrazine or (3-hydroxybenzyl)hydrazine, as indicated by Scatchard plots, or with 3-hydrazinopropionate, as shown by a spectrophotometric titration. Slow-binding inhibition does not appear to be the result of a significant enzyme conformational change because there is no change in the tryptophan fluorescence of GABA-AT upon binding either methylhydrazine or 3-hydrazinopropionate. Implications for the design of hydrazine inhibitors of GABA-AT are discussed.
“What’s your definition of dirty, baby?”: Sex in music video

As sexuality in music video becomes more intense and more frequent, it requires more attention by scholars. This essay summarizes the findings of two decades’ worth of research on music video, most of which focuses on sexual and violent content in the videos. In addition, we suggest a typology of how sexuality is indicated and used by artists—especially female artists—to define their images and attract audiences.
Determining Human Control Intent Using Inverse LQR Solutions

In this paper, we have developed a method for determining the control intention in human subjects during a prescribed motion task. Our method is based on the solution to the inverse LQR problem, which can be stated as: does a given controller K describe the solution to a time-invariant LQR problem, and if so, what weights Q and R produce K as the optimal solution? We describe an efficient Linear Matrix Inequality (LMI) method for determining a solution to the general case of this inverse LQR problem when both the weighting matrices Q and R are unknown. Additionally, we propose a gradient-based, least-squares minimization method that can be applied to approximate a solution in cases when the LMIs are infeasible. We develop a model for an upright seated-balance task which will be suitable for identification of human control intent once experimental data is available.Copyright © 2013 by ASME
Dry Pressing Boehmite Gels for the Fabrication of Monolithic α-Al2O3

It is demonstrated that dense alpha alumina can be fabricated by pressing ethanol-dispersed, α-Al2O3 seeded boehmite. Green bodies were formed by uniaxially pressing either water or ethanol dispersed gel powder and then isostatically pressing the compacts at 280 MPa. Green microstructure and alumina densification are correlated with gel agglomerate size and dispersing medium. The ethanol-dispersed specimens showed better sinterability than the water-dispersed specimens, and sintered to more than 99% theoretical density at 1300°C. It is shown that softer gel agglomerates were obtained by alcohol dispersion and resulted in better green microstructure and higher sintered density.
Transport Properties of GaAs

The transport properties of the electrons in GaAs have been investigated; i.e., the absolute values of the electron drift velocity, the diffusion coefficient, and the trapping time have been measured for the first time as a function of the electric field. To measure the velocity at the electron, the response of a reversed-bias Schottky barrier-$I\ensuremath{-}{n}^{+}$ GaAs device to a short pulse (0.1 nsec) of high-energy electrons was measured. The incident electrons create a sheet of charges in the semiconductor very close to the cathode. The electrons move across the diode under the influence of the applied electric field and induce a current in the contacts until they reach the anode. The width of the induced current pulse is a measure of the transit time of the electrons. With a knowledge of the width of the field region ($I$ layer), the drift velocity corresponding to the particular bias field can be accurately determined. The specimen used in this experiment consists of a slab of semi-insulating boat-grown GaAs cut in the [100] and [111] directions. Thin contacts were evaporated on each face; one, the cathode contact, less than 1000 \AA{} thick, forms the noninjecting Schottky barrier. The other, the anode, is ohmic. The experimental results are in excellent agreement with the Butcher-Fawcett theory, with a low-field mobility of 7500 ${\mathrm{cm}}^{2}$/V sec, a threshold field of 3300 V/cm, and an initial negative mobility of 2600 ${\mathrm{cm}}^{2}$/V sec. Signs, but no strong evidence, of the minimum velocity being reached up to the highest field used, 14 kV/cm, were observed. We have also measured by the same method the velocity-field relation over a range of ambient temperatures from 160 to 340\ifmmode^\circ\else\textdegree\fi{}K. From the measurement of the difference between the rise and the fall time of the induced current pulse, which is a measure of the spread of the electron layer created at the cathode by electron bombardment, it was possible to obtain the diffusion coefficient as a function of the electric field. The diffusion coefficient is sharply peaked (900 ${\mathrm{cm}}^{2}$/sec) at the threshold field and decrease to a value slightly less than 200 ${\mathrm{cm}}^{2}$/sec at high field. The experimental results are in considerable disagreement with the theoretical prediction. This disagreement may possibly be due to the velocity fluctuation arising from the rapid electron intervalley transfers which have not been taken into account in the theory by Butcher and Fawcett. Finally, measurement of the number of electrons trapped during the electron transit time across the specimen yields the variation of the trapping time as a function of the electric field.
Thermodynamic reciprocity of the inhibitor binding to the active site and the interface binding region of IB phospholipase A2.

Interfacial activation of pig pancreatic IB phospholipase A2 (PLA2) is modeled in terms of the three discrete premicellar complexes (Ei#, i = 1, 2, or 3) consecutively formed by the cooperative binding of a monodisperse amphiphile to the i-face (the interface binding region of the enzyme) without or with an occupied active site. Monodisperse PCU, the sn-2-amide analogue of the zwitterionic substrate, is a competitive inhibitor. PCU cooperatively binds to the i-face to form premicellar complexes (Ẽi, i = 1 or 2) and also binds to the active site of the premicellar complexes in the presence of calcium. In the ẼiI complex formed in the presence of PCU and calcium, one inhibitor molecule is bound to the active site and a number of others are bound to the i-face. The properties of the Ẽi complexes with PCU are qualitatively similar to those of Ei# formed with decylsulfate. Decylsulfate binds to the i-face but does not bind to the active site in the presence of calcium, nor does it interfere with the binding of...