cssi/SciSciGPT-SciSciNet huggingface dataset:
Active Entanglement-Tracking Microrheology Directly Couples Macromolecular Deformations to Nonlinear Microscale Force Response of Entangled Actin

We track the deformation of discrete entangled actin segments while simultaneously measuring the resistive force the deformed filaments exert in response to an optically driven microsphere. We precisely map the network deformation field to show that local microscale stresses can induce filament deformations that propagate beyond mesoscopic length scales (60 μm, >3 persistence lengths lp). We show that the filament persistence length controls the critical length scale at which distinct entanglement deformations become driven by collective network mechanics. Mesoscale propagation beyond lp is coupled with nonlinear local stresses arising from steric entanglements mimicking cross-links.
Never say never: The appropriate and inappropriate use of praise and feedback for students with learning and behavioral disabilities.

Abstract The use of verbal reinforcement has longstanding support in encouraging desired student responses. For students with learning and behavioral disabilities, the use of verbal reinforcement through behavior specific praise (BSP) and feedback are promising practices for improving academic and behavioral outcomes. While these strategies are relatively straightforward to implement, they are often applied inappropriately. Thus, specific guidelines should be followed to ensure that BSP and feedback are used effectively. The purpose of this chapter is to provide an overview of BSP and feedback related specifically to students with learning and behavioral disabilities, provide theoretical and empirical support for these practices, offer research-based recommendations for implementation, and identify common errors to avoid.
Right Hepatic Lobectomy: Extrahepatic Ligation

Right hepatic lobectomy is indicated for either a primary hepatic tumor or well-selected metastatic cancer localized to the right lobe of the liver. This chapter describes indications, essential steps, variations, and complications of this procedure. It provides a detailed template operative note for the procedure.
3.37 μW/Ch modular scalable neural recording system with embedded lossless compression for dynamic power reduction

We report a neural recording system with embedded lossless compression using spatiotemporal correlation and sparsity of neural signals to reduce dynamic power (P d ) dissipation for data transmission in high-density neural recording systems. We could successfully compress the data rate of neural signals by a factor of 5.35 (local field potential, LFP) and 10.54 (action potential, AP), respectively. Consequently we reduced Pd consumption by 89% while achieving the state-of-the-art recording performance of 3.37 μW/Ch, 5.18 μV rms input-referred noise, and 3.41NEF2Vdd.
Default publicness: Queer youth of color, social media, and being outed by the machine:

This article finds that US queer youth of color prefer Tumblr to express intimate feelings and personal politics over other social media such as Facebook. It is based on 5 years of cyberethnographi...
Beaked whales demonstrate a marked acoustic response to the use of shipboard echosounders

The use of commercial echosounders for scientific and industrial purposes is steadily increasing. In addition to traditional navigational and fisheries uses, commercial sonars are used extensively for oceanographic research, benthic habitat mapping, geophysical exploration, and ecosystem studies. Little is known about the effects of these acoustic sources on marine animals, though several studies have already demonstrated behavioural responses of cetaceans to shipboard echosounders. Some species of cetaceans are known to be particularly sensitive to acoustic disturbance, including beaked whales. In 2011 and 2013, we conducted cetacean assessment surveys in the western North Atlantic in which a suite of Simrad EK60 echosounders was used to characterize the distribution of prey along survey tracklines. Echosounders were alternated daily between active and passive mode, to determine whether their use affected visual and acoustic detection rates of beaked whales. A total of 256 groups of beaked whales were sighted, and 118 definitive acoustic detections were recorded. Regression analyses using generalized linear models (GLM) found that sea state and region were primary factors in determining visual sighting rates, while echosounder state was the primary driver for acoustic detections, with significantly fewer detections (only 3%) occurring when echosounders were active. These results indicate that beaked whales both detect and change their behaviour in response to commercial echosounders. The mechanism of this response is unknown, but could indicate interruption of foraging activity or vessel avoidance, with potential implications for management and mitigation of anthropogenic impacts.
Efficient Repair of Polluted Machine Learning Systems via Causal Unlearning

Machine learning systems, though being successful in many real-world applications, are known to remain prone to errors and attacks. A major attack, called data pollution, injects maliciously crafted training data samples into the training set, causing the system to learn an incorrect model and subsequently misclassify testing samples. A natural solution to a data pollution attack is to remove the polluted data from the training set and relearn a clean model. Unfortunately, the training set of a real-world machine learning system can contain millions of samples; it is thus hopeless for an administrator to manually inspect all of them to weed out the polluted ones. This paper presents an approach called causal unlearning and a corresponding system called KARMA to efficiently repair a polluted learning system. KARMA dramatically reduces the manual effort of administrators by automatically detecting the set of polluted training data samples with high precision and recall. Evaluation on three learning systems show that KARMA greatly reduces manual effort for repair, and has high precision and recall.
Social Intelligence Attenuates Association between Peer Victimization and Depressive Symptoms among Adolescents.

Objective Peer victimization is linked to psychological distress, but some youth are less affected than others. Identifying protective factors can inform prevention programs. Using longitudinal data from 7th graders we tested the role of social intelligence as a protective factor in the relation between peer victimization and depressive symptoms. Method Students (N = 986; 54% female; 43% non-white) from three schools provided self-report data via computer-assisted survey interviews in the fall (Time 1, T1) and spring (Time 2, T2) of 7th grade. Results Females reported more depressive symptoms and less physical victimization than males but did not differ from males on social intelligence or relational victimization. Regression analyses controlling for T1 depressive symptoms and other potential confounds revealed that both physical and relational victimization were positively and significantly associated with T2 depressive symptoms, but the strength of the relation varied by gender and by social intelligence. Specifically, the associations between victimization and depressive symptoms were stronger among females than males and among those with low or moderate rather than high social intelligence. Conclusions Social intelligence may protect youth from the psychological harms of peer victimization and could be an effective target of prevention programming.
Error Sensitivity in Reconfigurable OTA Chamber Field Synthesis

Prior analysis of the reconfigurable over-the-air chamber – a chamber designed for over-the-air testing of wireless devices – has not incorporated error in the currents when synthesizing fields incident on the device under test. This work incorporates these errors into the model relating currents to the synthesized fields and uses the analysis to quantify the impact of errors on the system performance. The analysis reveals that the signal-to-noise ratio required to achieve a certain level of error in the synthesized field increases with the number of antennas used for synthesis, with the observations suggesting that such chambers must be carefully designed to achieve the correct performance/complexity balance.
TLR7 Expression Reveals Novel Bronchodilating Mechanism of Imidazoquinoline Agonists

Background: Toll-like receptor 7 (TLR7) imidazoquinoline agonists bronchodilate guinea pig and human airways partly via nitric oxide production. Aim: To define airway TLR7 expression and the mechanism of TLR7 agonist-mediated bronchodilation. Methods: Guinea pig airways were suspended in Krebs in an organ bath, contracted (MCh, 3µM) and treated with TLR7 agonist R837 (10-300µM). Some airways were pre-treated with tetrodotoxin (TTX; 1µM) or tested in calcium-free Krebs. TLR7 expression was assessed using RNAScope in situ hybridization followed by immunohistochemistry for neurons (PGP9.5). Separately, cultured airway smooth muscle and sensory ganglia loaded with a fluorescent nitric oxide (NO-ON) or calcium indicator (Fluo-4-AM) were treated with R837 (30-100µM) and imaged by confocal microscopy. Results: TLR7 agonist R837 relaxed precontracted airways. R837-mediated relaxation was unaffected by TTX or by the absence of extracellular calcium. TLR7 was expressed in satellite glial cells (Fig. 1, arrows), but not airway neurons or smooth muscle. R837 increased nitric oxide in satellite cells, but not in neurons or smooth muscle, whereas R837 increased intracellular calcium in neurons, smooth muscle and satellite cells. Conclusions: TLR7 agonists relax airways via satellite cell nitric oxide release and possibly TLR7-independent effects on smooth muscle calcium. TLR7 agonists are potential bronchodilators for human development.
The Relationship between Maternal Depression, Externalizing and Internalizing Problems in Children, and Caregiving Burden in Urban Low-Income Ethnic and Racial Minority Families

A strong relationship exists between maternal depression and externalizing and internalizing problems in children, and caregiving burden might mediate this relationship. Yet, caregiving burden has rarely been tested as a mechanism underlying the relationship between maternal depression and child emotional and behavioral outcomes. Caregiving burden might be especially high in ethnic and racial minority mother-child dyads in low-income settings where there are more stressors in the environment and rates of maternal depression are elevated. A path analysis with 132 low-income urban mothers who mostly identified as racial and ethnic minorities confirmed our hypothesis that maternal depression has a direct effect on child externalizing and internalizing problems, and also an indirect effect through caregiving burden. We discuss implications of the findings with respect to research, practice, and policy with low-income, ethnic and racial minority families whose mothers have depression and care for children who exhibit externalizing and internalizing problems.
A Market Place Solution for Energy Transaction on Ethereum Blockchain

In the recent decade, self-consumption and local renewable energy communities are growing, especially in California, North Carolina, Arizona and Nevada. In these communities, approximately twenty percent of electricity comes from solar generation. However, what happens if a household generates more than what they consumeƒ In most cases, the excess energy would go back to the grid with little to no compensation given by the energy utility. In today’s market, there are countless homeowners who would like to profit from their own PV system. Unfortunately, there is no energy marketplace that would allow homeowners to sell or purchase energy to and from their neighbors. Luckily with blockchain, this idea becomes a reality. With the use of distributed ledger technology, it is possible to perform energy transactions in near-real time from a prosumer to consumer without the need of a central authority. Our thesis suggests ways to handle the facilitation of energy transactions using an Ethereum blockchain system in an effortless and efficient way.
8.10 – Biological Fluxes in the Ocean and Atmospheric pCO2

The biological pump in the ocean has a strong impact on the pCO2 of the atmosphere, potentially acting as a feedback to future changes in climate or ocean pH. However, the characterization of the strength of the biological pump today is less than ideal: there is a general discrepancy between direct measurements with sediment traps versus estimates based on bottle incubations, satellite data, and models. As a result, our ability to predict the future response of the biological pump is embryonic. Changes in primary production and calcification rates, which could impact sinking fluxes through changes in ballasting and marine snow aggregation, can be envisioned, but making reliable quantitative predictions is still elusive. The impact on atmospheric CO2 depends on how the ocean carbon and nutrient cycles respond to the change. The goal of this chapter is to synthesize the impacts of biological fluxes in the ocean on the CO2 concentration of the atmosphere, and to discuss ways in which biological fluxes might respond to past and future changes in climate and the chemistry of the oceans, such as ocean acidification. The intensities of these interactions will determine the strength, and the sign, of any carbon cycle feedback from the ocean to Earth's climate.
A Legitimate Call for Separate Government

Two separate notions on who is an Anglophone have been gathering attention and shaping up against one another since the onset of political unrest in the North-West and South-West administrative regions of the Republic of Cameroon. The first and prevailing notion, especially outside of the country, is that Anglophones are English-speakers of the country’s English-speaking area corresponding to the former British Southern Cameroons. In the background of this notion is the assumption that Anglophones are the bulk of Cameroonians, wherever they are, who have been presumably educated in English and have thus become, more or less, the bearers of English language and British culture. Common law and the British-inspired educational curriculum have been epitomized by the demonstrations of lawyers and teachers as the expression of that culture and its resilient facade in the country’s political institutions. The provocative status that our first notion of Anglophone confers to English language and British culture in an African country, which as Achille Mbembe wrote might make some laugh, cannot be taken seriously unless both the administration of justice and the provision of minimal genuine education are examined within the context of the struggle of the people of the former British Southern Cameroons to resist attempts by the central government of Cameroon to undermine any institutional difference with the former French Cameroun, in the name of harmonization, while upholding its institutional borrowings and channels with the Republic of France through sustained and ceaselessly renewed cooperation and ever more bolstered technical assistance.The second notion is a peculiar one. For ordinary Cameroonians, an Anglophone is he or she who is native to the two regions of the North-West and South-West. However, the peculiarity of this notion comes with the idea that being a native of the region, or of any place in the country for that matter, has neither to do with being born there nor being able to speak the putative language of the place. It all has to do with being able to trace and materialize one’s patrilineal descent to the place back to colonial era. In that sense, an Anglophone may not necessarily be someone born or domiciled in former British Southern Cameroons – but these facts will not diminish an iota of their ‘Anglophoneness’. Their genealogy bears testimony to their birth right as Anglophones. There have been accusations of deceit regarding people’s supposedly real origin at times of dissension on tactics, especially when it related to enforcing ghost towns or boycotting schools.
Brown adipose expansion and remission of glycemic dysfunction in obese SM/J mice

Disruption of glucose homeostasis increases the risk of type II diabetes, cardiovascular disease, stroke, and cancer. We leverage a novel rodent model, the SM/J mouse, to understand glycemic control in obesity. On a high fat diet, obese SM/J mice initially develop impaired glucose tolerance and elevated fasting glucose. Strikingly, their glycemic dysfunction resolves by 30 weeks of age despite persistence of obesity. A prominent phenotype is that they dramatically expand their brown adipose depots as they resolve glycemic dysfunction. This occurs naturally and spontaneously on a high fat diet, with no temperature or genetic manipulation. When the brown adipose depot is removed from normoglycemic obese mice, fasting blood glucose and glucose tolerance revert to unhealthy levels, and animals become insulin resistant. We identified 267 genes whose expression changes in the brown adipose when the mice resolve their unhealthy glycemic parameters, and find the expanded tissue has a healthier expression profile of cytokines and extracellular matrix genes. We describe morphological, physiological, and transcriptomic changes that occur during the unique brown adipose expansion and remission of glycemic dysfunction in obese SM/J mice. Understanding this phenomenon in mice will open the door for innovative therapies aimed at improving glycemic control in obesity.
Efficacy and Safety of the Telestroke Drip-And-Stay Model: A Systematic Review and Meta-Analysis.

Abstract Objectives To compare outcomes between two models of acute ischemic stroke care. Namely 1) “drip-and-stay”, i.e. IV tissue plasminogen activator (tPA) administered at a spoke hospital in a telestroke network, with the patient remaining at the spoke, versus 2) “drip-and-ship”, i.e. tPA administered at a spoke hospital with subsequent patient transfer to a hub hospital, and 3) “hub”, i.e. tPA and subsequent treatment at a hub hospital. Materials and Methods We performed a systematic review and meta-analysis according to PRISMA guidelines. Literature searches of MEDLINE, Embase, and Cochrane from inception-October 2019 included randomized control trials and observational cohort studies comparing the drip-and-stay model to hub and drip-and-ship models. Outcomes of interest were functional independence (modified Rankin Scale ≤ 1), symptomatic intracranial hemorrhage (sICH), mortality, and length of stay. Pooled effect estimates were calculated using a fixed-effects meta-analysis and random-effects Bayesian meta-analysis. Non-inferiority was calculated using a fixed-margin method. Results Of 2806 unique records identified, 10 studies, totaling 4,164 patients, fulfilled the eligibility criteria. Meta-analysis found no significant difference in functional outcomes (mRS0-1) (6 studies, RR=1.09, 95%CI 0.98–1.22, p=0.123), sICH (8 studies, RR=0.98, 95%CI 0.64–1.51, p=0.942), or 90-day mortality (5 studies, RR=0.98, 95%CI 0.73–1.32, p=0.911, respectively) between patients treated in a drip-and-stay model compared to patients treated in drip-and-ship or hub models. There was no significant heterogeneity in these outcomes. Drip-and-stay outcomes (mRS 0–1, sICH) were non-inferior when compared to the combined group. Conclusions Our findings indicate that drip-and-stay is non-inferior to current models of drip-and-ship or hub stroke care, and may be as safe and as effective as either.
Sparta: high-performance, element-wise sparse tensor contraction on heterogeneous memory

Sparse tensor contractions appear commonly in many applications. Efficiently computing a two sparse tensor product is challenging: It not only inherits the challenges from common sparse matrix-matrix multiplication (SpGEMM), i.e., indirect memory access and unknown output size before computation, but also raises new challenges because of high dimensionality of tensors, expensive multi-dimensional index search, and massive intermediate and output data. To address the above challenges, we introduce three optimization techniques by using multi-dimensional, efficient hashtable representation for the accumulator and larger input tensor, and all-stage parallelization. Evaluating with 15 datasets, we show that Sparta brings 28 -- 576× speedup over the traditional sparse tensor contraction with sparse accumulator. With our proposed algorithm- and memory heterogeneity-aware data management, Sparta brings extra performance improvement on the heterogeneous memory with DRAM and Intel Optane DC Persistent Memory Module (PMM) over a state-of-the-art software-based data management solution, a hardware-based data management solution, and PMM-only by 30.7% (up to 98.5%), 10.7% (up to 28.3%) and 17% (up to 65.1%) respectively.
Learning Lindley’s Recursion

Lindley’s recursion is one of the most important formula’s in queueing theory and applied probability. In this paper, we leverage stochastic simulation and current machine learning methods to learn the Lindley recursion directly from waiting time data of the G/G/1 queue. To this end, we use methods such as Gaussian Processes, k-Nearest Neighbors and Deep neural networks to learn the Lindley recursion. We also analyze specific parameter regimes for the M/M/1 to understand where learning the Lindley recursion may be easy or hard. Finally, we compare the machine learning methods to see how well we can predict the Lindley recursion multiple steps into the future with missing data.
The 3′ end of the human norovirus antigenomic sequence is required for its genomic RNA synthesis by RNA-dependent RNA polymerase

Norovirus genome is a single-stranded positive-strand RNA. To reveal the mechanism underlying the initiation of the norovirus genomic RNA synthesis by its RNA-dependent RNA polymerase (RdRp), we used an in vitro assay to detect the complementary RNA synthesis activity. Results showed that the purified recombinant RdRp synthesized the complementary positive-sense RNA from the 100 nt template corresponding to the 3' end region of the viral antisense genome sequence, but that RdRp did not synthesize the antisense genomic RNA from the 100 nt template, corresponding to the 5' end region of the positive-sense genome sequence. The 31 nt region at the 3' end of the RNA antisense template was then predicted to form the stem-loop structure. Its deletion resulted in the loss of complementary RNA synthesis by RdRp. The connection of the 31 nt to the 3' end of the positive-sense RNA template allowed to be recognized by the RdRp. Similarly, an electrophoretic mobility shift assay further revealed that RdRp bound to the antisense RNA specifically, but the 31 nt deletion at the 3' end lost the binding to RdRp. Therefore, combining this observation with further deletion and mutation analysis, we concluded that the predicted stem-loop structure in the 31 nt and region close to the antisense viral genomic stem sequences are important for initiating the positive-sense human norovirus genomic RNA synthesis by its RdRp.
Electrophysiological Recordings of the Polycystin Complex in the Primary Cilium of Cultured Mouse IMCD-3 Cell Line

PC-1 and PC-2 form an ion channel complex called the polycystin complex, which predominantly localizes to a small hair-like organelle called the primary cilium. The polycystin complex permeates cations, K+, Na+, and Ca2+, and has an unusual 1:3 stoichiometry that combines one PC-1 subunit with three PC-2 subunits. However, the small size and shape of primary cilia impose technical challenges to study the polycystin complex in its native environment. In this paper, we describe the methodology to directly record ion channel activity in primary cilia. This method will allow a detailed functional characterization of how mutations within the polycystin complex cause Autosomal Dominant Polycystic Kidney Disease (ADPKD), essential to develop novel therapeutics for this ciliopathy.
SU-E-T-317: Dosimetric Evaluation of Acuros XB Advanced Dose Calculation Algorithm in Head and Neck Patients

Purpose: The Acuros XB photon dose calculation algorithm is a newly implemented calculation technique within the Eclipse treatment planning system using deterministic solutions to the linear Boltzmann transport equations. The goal of this study is to assess the clinical impact of dose differences arising from a retrospective comparison of calculations performed using the Analytical Anisotropic Algorithm (AAA) and Acuros XB on patients. Methods: Ten head and neck patients receiving intensity modulated radiation therapy were selected as a pilot study. Initial evaluation was based on the percentage of the planning target volume (PTV) covered by the prescription dose, minimum dose within the PTV, and dose differences in critical structures. For patients receiving boost plans, dosimetric evaluations were performed on the plan sum of the primary and boost plans. Results: Among the ten patients there were a total of 21 PTVs corresponding to primary and boost volumes. Using the same normalization within Eclipse, the average percentage of the PTVs receiving the prescription dose were 95.6% for AAA and Acuros XB. The average minimum doses within the PTVs, expressed as a percentage of the prescription to the volume, were 82.3% and 83.6% for AAA and Acuros XB respectively. Neither comparison showed differences with statistical significance when subjected to a paired t-test. Statistical significance was found in the average difference of the maximum dose for the mandible (242.5cGy, p=0.0005) and cord with a 5mm radial expansion (105.0cGy, p=0.0005) and in the median dose for the left parotid (25.0cGy, p=0.0423) and oral cavity (36.3cGy, p=0.002). Conclusion: The Acuros XB dose calculation algorithm did not exhibit significant differences in PTV coverage when compared to the AAA algorithm. Significant differences in critical structures are likely attributed to the structures proximity to high atomic number materials or air cavities, regions of known difficulty for the AAA algorithm.
Pattern Recognition Molecules Activated by Chlamydia muridarum Infection of Cloned Murine Oviduct Epithelial Cell Lines

Chlamydia trachomatis is the most common bacterial sexually transmitted disease in the United States and a major cause of female infertility due to infection-induced Fallopian tube scarring. Epithelial cells are likely central to host defense and pathophysiology as they are the principal cell type productively infected by C. trachomatis. We generated cloned murine oviduct epithelial cell lines without viral or chemical transformation to investigate the role of the TLRs and cytosolic nucleotide binding site/leucine-rich repeat proteins Nod1 and Nod2 in epithelial responses to Chlamydia muridarum infection. RT-PCR assays detected mRNA for TLR2 (TLRs 1 and 6), TLR3, and TLR5. No mRNA was detected for TLRs 4, 7, 8, and 9. Messenger RNAs for Nod1 and Nod2 were present in the epithelial cell lines. Oviduct epithelial cell lines infected with C. muridarum or exposed to the TLR2 agonist peptidoglycan secreted representative acute phase cytokines IL-6 and GM-CSF in a MyD88-dependent fashion. Infected epithelial cell lines secreted the immunomodulatory cytokine IFN-beta, even though C. muridarum does not have a clear pathogen-associated molecular pattern (PAMP) for triggering IFN-beta transcription. The oviduct epithelial lines did not secrete IFN-beta in response to the TLR2 agonist peptidoglycan or to the TLR3 agonist poly(I:C). Our data identify TLR2 as the principal TLR responsible for secretion of acute phase cytokines by C. muridarum-infected oviduct epithelial cell lines. The pattern recognition molecule responsible for infection-induced IFN-beta secretion by oviduct epithelial cells remains to be determined.
Roles and Power within Federal Problem Solving Courtroom Workgroups

Problem solving (PS) courts (e.g., drug, family, gang, prostitution, reentry) are becoming more commonplace. Today, PS courts exist or are planned in nearly all of the ninety-four U.S. federal districts. These courts focus on integrating therapeutic jurisprudence into the courtroom environment while emphasizing group decision-making processes among courtroom workgroup members. In this legal setting, courtroom workgroup teams, regularly consisting of judges, prosecutors, defense attorneys, probation officers (POs), and treatment providers engage a collective, case management approach to decision making with shared power among team members. However, despite the court’s therapeutic and collaborative design, we find that POs wield powerful influence in decision making. Informed by sixteen months of qualitative fieldwork, including semistructured interviews, observation of courtroom workgroup meetings, and court observations in five federal PS courts in three federal districts, we find that POs exert undetected informational, technical, and relational power within the PS courtroom workgroup. This role and its accompanying power transforms POs into key decision makers, regardless of PS court type, workgroup dynamics, and decision-making style. The POs’ role makes them critical contributors to the outcomes in federal PS courts with important implications for punishment decisions in the federal justice system. With an increasing number of PS courts currently in the planning stages at the federal level, our study has implications for the structure and decision outcomes in these growing courtroom workgroups.
Carbohydrate– Carbohydrate Interactions

Carbohydrate–carbohydrate interactions have been suggested as mediators of cell adhesion and aggregation. Studies of four different interactions— sponge cell aggregation, embryo and myelin compaction, and melanoma cell adhesion— have provided insights into the role of the saccharides in these events. The biological context of these associations as well as the results of experiments using biophysical and chemical model systems are described.
Equine-Assisted Therapies: Complementary Medicine or Not?.

Equine-assisted therapies are interventions that use the unique qualities of a horse to assist persons with disabilities to improve their gross motor, language, social, and self-help skills. Programs offering these services are varied and operate on all major continents across the world. The effectiveness of equine-assisted therapies is generally supported by research, although most studies have been small and the rigor of much of the research has been less than optimal. This paper describes the different types of riding programs and reviews research examining their effectiveness for children and adults with developmental and acquired motor or cognitive disabilities, and psychological or psychiatric impairments. Recommendations are made for future research to provide evidence of the broader benefits of using horses to enhance the lives of people with disabilities.
Disulfide characterization of CD31 (PECAM)

Publisher Summary This chapter describes the disulfide characterization of CD31 (PECAM). CD31 is a 100 kDa integral membrane glycoprotein found in endothelial intercellular junctions, platelets, and monocytes. CD31 is believed to be involved in the regulation of endothelial cell migration, thus it is probably involved in vascular development, wound repair, and angiogenesis. Although binding of CD31 is homophilic, there is some evidence that it may bind other members of the cellular adhesion molecule family. Common to the adhesion molecules is the immunoglobulin (Ig) homology unit that consists of two β-sheets stabilized by a disulfide bond. Few adhesion molecule disulfide structures are determined in the chapter. Most disulfide structures are assumed by structural homology with other proteins in the same family or superfamily. The adhesion molecules are relatively, hydrophobic, and heavily glycosylated. Deglycosylation of the native protein ( N - and O - sites) reduce the complexity of peptide maps and simplify mass spectral data, allowing for simpler disulfide assignments.
Neutral pumping rates for a next step tokamak ignition device

Neutral pumping rates are calculated for pump-limiter and divertor options of a next step tokamak ignition device using a method that accounts for the coupled effects of neutral transport and plasma transport. For both pump limiters and divertors the plasma flow into the channel surrounding the neutralizer plate is greatly reduced by the neutral recycling. The fraction of this flow that is pumped can be large (>50%) but in general is dependent on the particular geometry and plasma conditions. It is estimated that pumping speeds greater than or approximately 10/sup 5/ L/s are adequate for the exhaust requirements in the pump-limiter and the divertor cases.
Signaling Networks: The Origins of Cellular Multitasking

One characteristic common to all organisms is the dynamic ability to coordinate constantly one's activities with environmental changes. The function of communicating with the environment is achieved through a number of pathways that receive and process signals, not only from the external environment but also from different regions within the cell. Individual pathways transmit signals along linear tracts resulting in regulation of discrete cell functions. This type of information transfer is an important part of the cellular repertoire of regulatory mechanisms. However, as increasingly larger numbers of cell signaling components and pathways are being identified and studied, it has become apparent that these linear pathways are not free-standing entities but parts of larger networks. Several articles in this review series describe in exquisite detail how individual classes of signaling pathways are organized and function. As we understand the details of such functional organization and move to the next level of analyzing integrated cellular functions, it will become increasingly important to identify and study the properties and capabilities of signaling networks as a whole. One of the more surprising revelations that is coming from the initial studies of networks and component interactions in different cell types is that there may be a general signaling network that receives signals from cell type–specific inputs (i.e., receptors) and engage cell type–specific machinery. The molecular identity of the signaling components and their interacting partners may be cell type–specific, but the overall function of these components and the logic of the circuitry is preserved from cell type to cell type. We will compare two cell types, T cells (Dustin and Chan, 2000 [this issue of Cell]) and the postsynaptic region of glutamatergic synapses, to develop this argument. Signaling networks are likely to have a variety of emergent properties and capabilities. We will describe some of our current insights into how signaling networks are organized and how this dynamic spatial organization can lead to higher order cellular capabilities. As an example of such capabilities, we further develop the concept that the ability of a cell to regulate spatially resolved multiple functions in a coordinated manner arises from the organization of signaling pathways into networks.
Toward a more complete alloy

Many model-finding tools, such as Alloy, charge users with providing bounds on the sizes of models. It would be preferable to automatically compute sufficient upper-bounds whenever possible. The Bernays-Schonfinkel-Ramsey fragment of first-order logic can relieve users of this burden in some cases: its sentences are satisfiable iff they are satisfied in a finite model, whose size is computable from the input problem. Researchers have observed, however, that the class of sentences for which such a theorem holds is richer in a many-sorted framework--which Alloy inhabits--than in the one-sorted case. This paper studies this phenomenon in the general setting of order-sorted logic supporting overloading and empty sorts. We establish a syntactic condition generalizing the Bernays-Schonfinkel-Ramsey form that ensures the Finite Model Property. We give a linear-time algorithm for deciding this condition and a polynomial-time algorithm for computing the bound on model sizes. As a consequence, model-finding is a complete decision procedure for sentences in this class. Our work has been incorporated into Margrave, a tool for policy analysis, and applies in real-world situations.
Repair Pathway Choices and Consequences at the Double-Strand Break

DNA double-strand breaks (DSBs) are cytotoxic lesions that threaten genomic integrity. Failure to repair a DSB has deleterious consequences, including genomic instability and cell death. Indeed, misrepair of DSBs can lead to inappropriate end-joining events, which commonly underlie oncogenic transformation due to chromosomal translocations. Typically, cells employ two main mechanisms to repair DSBs: homologous recombination (HR) and classical nonhomologous end joining (C-NHEJ). In addition, alternative error-prone DSB repair pathways, namely alternative end joining (alt-EJ) and single-strand annealing (SSA), have been recently shown to operate in many different conditions and to contribute to genome rearrangements and oncogenic transformation. Here, we review the mechanisms regulating DSB repair pathway choice, together with the potential interconnections between HR and the annealing-dependent error-prone DSB repair pathways.
Multi-frequency, multi-phase scan chain

The use multiple clocks presents an interesting problem to scan design. Traditionally, a separate scan chain has been provided for each clock, which results in longer than necessary scan operations due to unbalanced scan chain length. A set of methods that would allow mixing of memory elements clocked at different frequencies and phases in a single scan chain is presented and the proofs of the correct operation of the methods are given. If multiple scan chains are allowed, these methods make it possible to form scan chains of equivalent length for the savings in test application time and tester memory.
On Being First: Dogma, Disease and Domination in the Rise of an African Church

What might the early institutional history of an indigenous African Church reveal about the institutionalisation of religious innovation? What might findings suggest about the impact of both internal organisational processes and extra-institutional pressures on the routinization of charisma? This article addresses these questions by examining the rise of Christ Apostolic Church, an Aladura church of the Yoruba of Nigeria, and focusing on the interplay of first, the global propagation of Christianity; second, colonial domination; third, symbolic reformulation; and finally, the pursuit of well-being in the face of epidemic disease. This investigation provides a case study of how people negotiate social and natural obstacles while constructing enduring institutional structures. Furthermore, it is argued that, rather than obstructing this religious movement, epidemics, colonial domination and missionary opposition fuelled its transformation into an institutional church.
Treatment of kidney stones: current lithotripsy devices are proving less effective in some cases

When the Dornier HM3 lithotriptor was introduced in the early 1980s, shock-wave lithotripsy (SWL) rapidly became the preferred treatment for most upper-tract calculi. A number of second- and third-generation machines have since become available. This Viewpoint discusses the evolution of SWL technology, and highlights concerns over the limitations of modern devices.
Possible Mechanisms for the Enzymatic Condensation of Porphobilinogen

THE problem of the mechanism of the enzymatic condensation of four moles of porphobilinogen (PBG) to form uroporphyrinogen III (urogen III) remains unsolved. Bogorad1–3 has been able to direct the course of this condensation in vitro by using one or two enzyme systems. Porphobilinogen deaminase (PBG-D) or uroporphyrin I synthetase from spinach catalyses the formation of uroporphyrin I (urogen I) from porphobilinogen. Uroporphyrinogen isomerase (U-Is) or uroporphyrinogen III co-synthetase from wheat germ and PBG-D direct the formation of urogen III from porphobilinogen. Kinetic investigations carried out by Bogorad suggest that the action of PBG-D on porphobilinogen is rate-determining and that uroporphyrinogen isomerase participates in a faster step for which porphobilinogen is also a substrate. Uroporphyrinogen isomerase does not act on porphobilinogen alone nor on urogen I (ref. 4). This suggests that some intermediate, the synthesis of which is catalysed by PBG-D, and porphobilinogen are substrates for uroporphyrinogen isomerase.
A comparison of the distribution and morphology of thalamic, cerebellar and spinal projection neurons in rat trigeminal nucleus interpolaris

Abstract The retrograde transport of horseradish peroxidase was used to examine and compare the distribution and morphology of thalamic, cerebellar and spinal projecting neurons in rat trigeminal nucleus interpolaris following large injections into their respective targets. The regional distribution of these three populations was evaluated in relation to the six cytoarchitecturally distinct regions which characterize the nucleus. Cerebellar projecting neurons were distributed throughout the rostrocaudal extent of trigeminal nucleus interpolaris, but were infrequently present in its dorsolateral region and in the rostral pole of the nucleus. Thalamic projecting neurons exhibited a distribution pattern that extensively overlapped with that of the trigeminocerebellar neurons; however, they were particularly concentrated in caudal, dorsomedial and rostral, ventrolateral regions of the nucleus. Trigeminospinal projecting neurons exhibited a more restricted distribution within ventral and lateral regions of trigeminal nucleus interpolaris. Although the three populations of projection neurons could not be distinguished solely on the basis of somatic size or shape, distinct regional variations in the distribution and somatodendritic and axonal morphology of these neurons indicated that they arise largely from independent cell populations. However, several regions were identified in which specific cell types were likely to contribute to axonal collateralization among these pathways. In the ventrolateral magnocellular region of the nucleus, for example, more than half of the large multipolar-shaped neurons were retrogradely labeled after injections into each of the three target sites. The results of the present study indicate that the thalamic, cerebellar and spinal projections of trigeminal nucleus interpolaris arise from a morphologically heterogeneous group of neurons. In addition, regional variations in the distribution and morphology of these neurons provide evidence for the existence of functionally distinct regions that parallel the cytoarchitecturally defined regions of the nucleus. This study also provides indirect evidence for and against collateralization among these three projections within specific regions of the nucleus.
The Comparative Set Fallacy

This paper argues for the validity of inferences that take the form of: A is more X than B; therefore A and B are both X. After considering representative counterexamples, it is claimed that these inferences are valid if and only if the comparative terms in the inference are taken from no more than one comparative set, where a comparative set is understood to be comprised of a positive, comparative, and superlative, represented as {X, more X than, most X}. In all instances where arguments appearing to be of this form are invalid, it is the case that the argument has fallaciously taken terms from more than one comparative set. The fallacy of appealing to more than one comparative set in an inference involving comparative terms is shown to be analogous to the fallacy of equivocation in argumentation. The paper concludes by suggesting a conflation of logical issues with grammatical issues is the core difficulty leading some to consider inferences in the form of A is more X than B; therefore A and B are X to be invalid.
Knockout of REST/NRSF shows that the protein is a potent repressor of neuronally expressed genes in non‐neural tissues

The protein repressor element 1 silencing transcription factor/neuron restrictive silencer factor (REST/NRSF) is a negative regulator of neuronal genes that contain a particular DNA sequence, the neuron restrictive silencer element (NRSE). REST is expressed ubiquitously in non-neural tissues but is down-regulated in neural precursors and turned off in postmitotic neurons, suggesting that it can act both to prevent extraneural expression of certain genes and to delay the differentiation of neuronal subtypes. In a recent paper, Chen et al.(1) describe the production of a null mutant for REST in mice and the mosaic inactivation of REST function in chicken embryos. Knockout of REST led to malformations in several non-neural tissues, as well as apoptosis and embryonic lethality in mice. In addition, the expression of several REST target genes was derepressed in non-neural tissues and in neural progenitors in both mouse and chicken embryos. These studies clearly demonstrate that active repression of tissue-specific genes is required for proper tissue differentiation during embryonic development. BioEssays 21:372–376, 1999. © 1999 John Wiley & Sons, Inc.
The Polygenesis of the Neo-Arabic Dialects

This paper presents a framework within which the study of the development of neo-Arabic may be carried out. The present analysis investigates relative and demonstrative pronouns in peripheral neo-Arabic in light of NW Semitic isoglosses and suggests that the contemporary dialects originated in two Old Arabic dialect clusters. However, the distribution of the relative and demonstrative features in most neo-Arabic dialects indicates that there has been significant historical contact between the proposed original clusters. Thus, a conventional tree diagram is not capable of describing their development. This analysis suggests that the neo-Arabic dialects should be regarded as sedimentary structures, containing both genetic and koine features. In light of this, the author proposes that the diachronic study of neo-Arabic should be divided into two modules: the first is the study of the development of innovations found in neo-Arabic, regardless of dialect, from proto-Central Semitic, and the second is the study of the spread of these features throughout the neo-Arabic dialects through the mechanisms of contact presented here.
Model-based color image quantization

In this paper, we propose a new technique for halftoning color images. Our technique parallels recent work in model-based halftoning for both monochrome and color images; we incorporate a human visual model that accounts for the difference in the responses of the human viewer to luminance and chrominance information. Thus, the RGB color space must be transformed to a luminance/chrominance based color space. The color transformation we use is a linearization of the uniform color space L*a* b* which also decouples changes between the luminance and chrominance components. After deriving a tractable expression for total- squared perceived error, we then apply the method of Iterated Conditional Modes (ICM) to iteratively toggle halftone values and exploit several degrees of freedom in reducing the perceived error as predicted by the model.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.