cssi/SciSciGPT-SciSciNet huggingface dataset:
Risk and recovery among high school athletes who sustained at least one sports-related concussion.

Aim Evidence of factors explaining sports-related concussion (SRC) risk and recovery among high school athletes remains inconclusive. Materials & methods Prospective study of a real-world sample of high school athletes (n = 77) who sustained ≤1 SRC. Among those with multiple SRCs, recovery time between events was investigated. To investigate concussion risk, baseline characteristics of athletes with a single versus multiple SRC(s) were compared. Results Recovery time did not differ across events. There were no differences between those with a single versus multiple SRCs. Conclusion Recovery time between initial and subsequent concussive events did not differ, suggesting that prior concussion may not prolong recovery. Baseline characteristics did not explain heightened concussion risk. Investigation of these relationships using more representative samples is needed.
Nuclear Pore: A Bidirectional Transport Machinery

The human nuclear pore complex is a 120 nm structure composed of nearly 1000 protein molecules (multiple copies of nearly 30 different proteins) with a mass of 110–120 MDa. It spans the double membrane of the nuclear envelope and selectively transports both proteins, nucleic acids, and small signaling molecules bidirectionally. The diameter of the channel in the nuclear pore complex is approximately 5 nm in diameter and 45 nm in depth. Selective transport through the nuclear pore complex is mediated by nuclear transport receptors that bind to the cargo to be transported. Importins mediate transport of cargo molecules into the nucleus, whereas exportins facilitate the selective transport of cargo out of the nucleus. Cargoes with a nucleus localization signal are efficiently transported into the nucleus through the nuclear pore complex. The import and export cycles require GTP hydrolysis, and thus the transport process through the nuclear pore complex is energy-dependent. Since the nuclear pore complex is the gateway to the genome, the number of nuclear pore complexes varies during the different stages of the cell cycle. For example, between G1 and G2 phase of the cell cycle, the number of nuclear pore complexes at the nuclear envelope increase to accommodate greater transcriptional demand. Assembly of the nuclear pore complex like other cellular nanomachines is little understood.
Empirical Evidence of Changing Food Demand and Consumer Preferences in Russia

We investigate food preference changes in Russia that may have resulted from political, economic, and other changes. Our empirical framework utilizes advances in consumer theory and exploits provincial-level panel data on food consumption and supply shifters to identify price and income effects. Our findings indicate that consumers underwent a structural preference change that began in 2007 and continued into 2014. To illustrate the magnitude of this change, we contrast economic effects for select food commodities across regions. The new insights will be useful in designing timely and effective food and trade policies, as well as informing strategy decisions of agribusiness industry players.
The State of HRE in Higher Education Worldwide

How to define human rights is a matter of controversy. Scholars, human rights professionals, even politicians are weighing in on the debate. Academia, namely human rights curricula in higher education, plays a critical role in defining human rights. What topics are taught as part of a curriculum constitutes the knowledge content of human rights. This chapter analyzes human rights curricula around the world to establish what it reveals about how human right is understood in the academy. Then it relates this understanding to two current related debates: the health of the human rights movement (is it thriving or in decline), which depends on how human rights is defined (is it restricted to what is found in human rights law) or do most social justice issues fall under the umbrella of human rights? The conclusion is that there needs to be more consensus in higher education about what should be included in degree curricula.
Roles of sarcoplasmic reticulum Ca 2+ ATPase pump in the impairments of lymphatic contractile activity in a metabolic syndrome rat model

The intrinsic lymphatic contractile activity is necessary for proper lymph transport. Mesenteric lymphatic vessels from high-fructose diet-induced metabolic syndrome (MetSyn) rats exhibited impairments in its intrinsic phasic contractile activity; however, the molecular mechanisms responsible for the weaker lymphatic pumping activity in MetSyn conditions are unknown. Several metabolic disease models have shown that dysregulation of sarcoplasmic reticulum Ca2+ ATPase (SERCA) pump is one of the key determinants of the phenotypes seen in various muscle tissues. Hence, we hypothesized that a decrease in SERCA pump expression and/or activity in lymphatic muscle influences the diminished lymphatic vessel contractions in MetSyn animals. Results demonstrated that SERCA inhibitor, thapsigargin, significantly reduced lymphatic phasic contractile frequency and amplitude in control vessels, whereas, the reduced MetSyn lymphatic contractile activity was not further diminished by thapsigargin. While SERCA2a expression was significantly decreased in MetSyn lymphatic vessels, myosin light chain 20, MLC20 phosphorylation was increased in these vessels. Additionally, insulin resistant lymphatic muscle cells exhibited elevated intracellular calcium and decreased SERCA2a expression and activity. The SERCA activator, CDN 1163 partially restored lymphatic contractile activity in MetSyn lymphatic vessel by increasing phasic contractile frequency. Thus, our data provide the first evidence that SERCA2a modulates the lymphatic pumping activity by regulating phasic contractile amplitude and frequency, but not the lymphatic tone. Diminished lymphatic contractile activity in the vessels from the MetSyn animal is associated with the decreased SERCA2a expression and impaired SERCA2 activity in lymphatic muscle.
NIH Training and Education for Biomedical Data Science

In 2012, at the National Institutes of Health (NIH), the Working Group on Data and Informatics of the Advisory Committee to the NIH Director made recommendations about changes needed in NIH investments and procedures to assure that the research potential of biomedical big data would be fully realized. With its “Big Data to Knowledge” initiative as the pilot program, NIH leaders developed a strategic plan for data science, and tasked hundreds of staff with the assignment to develop implementation plans for its five goals. The plan, issued in 2018, has the overall goal of assuring that research, training and the products of research supported by the public funds adhere to the FAIR principles, meaning that the data be Findable, Accessible, Interoperable, and Reusable.
PDE1 inhibition modulates Cav1.2 channel to stimulate cardiomyocyte contraction

Rationale: Cyclic adenosine monophosphate (cAMP) activation of protein kinase A (PKA) stimulates excitation-contraction coupling, increasing cardiac contractility. This is clinically achieved by beta-adrenergic receptor stimulation (b-ARs) or inhibition of phosphodiesterase type-3 (PDE3i), though both approaches are limited by arrhythmia and chronic myocardial toxicity. Phosphodiesterase type-1 inhibition (PDE1i) also augments cAMP and enhances contractility in intact dogs and rabbits. Unlike b-ARs or PDE3i, PDE1i-stimulated inotropy is unaltered by b-AR blockade and induces little whole-cell Ca2+ ([Ca2+]i) increase. Positive inotropy from PDE1i was recently reported in human heart failure. However, mechanisms for this effect remain unknown. Objective: Define the mechanism(s) whereby PDE1i increases myocyte contractility. Methods and Results: We studied primary guinea pig myocytes that express the PDE1C isoform found in larger mammals and humans. In quiescent cells, the potent, selective PDE1i (ITI-214) did not alter cell shortening or [Ca2+]i whereas b-ARs or PDE3i increased both. When combined with low-dose adenylate cyclase stimulation, PDE1i enhanced shortening in a PKA-dependent manner but unlike PDE3i, induced little [Ca2+]i rise nor augmented b-ARs. b-ARs or PDE3i reduced myofilament Ca2+ sensitivity, and increased SR Ca2+ content and phosphorylation of PKA-targeted serines on troponin-I, myosin binding protein C, and phospholamban. PDE1i did not significantly alter any of these. However, PDE1i increased Cav1.2 channel conductance similarly as PDE3i (both PKA-dependent), without altering NCX current density. Cell shortening and [Ca2+]i augmented by PDE1i were more sensitive to Cav1.2 blockade and premature or irregular cell contractions and [Ca2+]i transients less frequent than with PDE3i. Conclusions: PDE1i enhances contractility by a PKA-dependent increase in Cav1.2 conductance with less total [Ca2+]i increase, and no significant changes in SR [Ca2+], myofilament Ca2+-sensitivity, or phosphorylation of critical EC-coupling proteins as observed with b-ARs and/or PDE3i. PDE1i could provide a novel positive inotropic therapy for heart failure without the toxicities of b-ARs and PDE3i.
Efficient Big-Data Access: Taxonomy and a Comprehensive Survey

The emerging systems are not only generating huge amounts of data but also expect this data to be analyzed expeditiously to drive online decision-making and control. Thus, identifying the most relevant data and making it available close to the computation becomes a central challenge in driving the big data revolution. Storage systems play a crucial role in enabling efficient access to the stored data and intelligent storage management techniques are thus central to addressing the problem. Generally, as the data volume increases, the marginal utility of an "average" data item tends to decline, which requires greater effort in identifying the most valuable data items and making them available with minimal overhead and latency. Data driven mechanisms have a big role to play in solving this needle-in-the-haystack problem. In this paper we propose a taxonomy to provide a structure for understanding the common issues surrounding these techniques. We discuss these techniques and articulate many research challenges and opportunities.
Reducing Intubation Time in Adult Cardiothoracic Surgery Patients With a Fast-track Extubation Protocol.

Background Prolonged intubation after cardiac surgery increases the risk of morbidity and mortality and lengthens hospital stays. Factors that influence the ability to extubate patients with speed and efficiency include the operation, the patient's baseline physiological condition, workflow processes, and provider practice patterns. Local problem Progression to extubation lacked consistency and coordination across the team. The purpose of the project was to engage interprofessional stakeholders to reduce intubation times after cardiac surgery by implementing fast-track extubation and redesigned care processes. Methods This staged implementation study used the Define, Measure, Analyze, Improve, and Control approach to quality improvement. Barriers to extubation were identified and reduced through care redesign. A protocol-driven approach to extubation was also developed for the cardiothoracic intensive care unit. The team was engaged with clear goals and given progress updates. Results In the preimplementation cohort, early extubation was achieved in 48 of 101 patients (47.5%) who were designated for early extubation on admission to the cardiothoracic intensive care unit. Following implementation of a fast-track extubation protocol and improved care processes, 153 of 211 patients (72.5%) were extubated within 6 hours after cardiac surgery. Reintubation rate, length of stay, and 30-day mortality did not differ between cohorts. Conclusions The number of early extubations following cardiac surgery was successfully increased. Faster progression to extubation did not increase risk of reintubation or other adverse events. Using a framework that integrated personal, social, and environmental influences helped increase the impact of this project.
Cost-Effectiveness Analysis of Adjuvant Therapy for BRAF-Mutant Resected Stage III Melanoma in Medicare Patients.

Adjuvant therapy for stage III melanoma improves several measures of patient survival. However, decisions regarding inclusion of adjuvant therapies in the formularies of public payers necessarily consider the cost-effectiveness of those treatments. The objective of this study is to evaluate the cost-effectiveness of four recently approved adjuvant therapies for BRAF-mutant stage III melanoma in the Medicare patient population. In this cost-effectiveness analysis, a Markov microsimulation model was used to simulate the healthcare trajectory of patients randomized to receive either first-line targeted therapy (dabrafenib–trametinib) or immunotherapy (ipilimumab, nivolumab, or pembrolizumab). The base case was a 65-year-old Medicare patient with BRAF V600E-mutant resected stage III melanoma. Possible health states included recurrence-free survival, adverse events, local recurrence, distant metastases, and death. Transition probabilities were determined from published clinical trials. Costs were estimated from reimbursement rates reported by CMS and the Red Book drug price database. Primary outcomes were costs (US$), life years, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs). Model robustness was evaluated using one-way and probabilistic sensitivity analyses. Dabrafenib–trametinib provided 1.83 QALYs over no treatment and 0.23 QALYs over the most effective immunotherapy, pembrolizumab. Dabrafenib–trametinib was associated with an ICER of $95,758/QALY over no treatment and $285,863/QALY over pembrolizumab. Pembrolizumab yielded an ICER of $68,396/QALY over no treatment and dominated other immunotherapies. Pembrolizumab is cost-effective at a conventional willingness-to-pay (WTP) threshold, but dabrafenib–trametinib is not. Though dabrafenib–trametinib offers incremental QALYs, optimization of drug pricing is necessary to ensure dabrafenib–trametinib is accessible at an acceptable WTP threshold.
A Review of The Psychopathic Mind: Origins, Dynamics, and Treatment

Psychopathy, as defined by Dr. Meloy, is “a deviant developmental disturbance characterized by an inordinate amount of instinctual aggression in the absence of an object relational capacity to bond.” The author initially provides a psychobiological foundation for understanding psychopathy and later uses object relations theory to conceptualize this disorder further. Four sections, consisting of eight chapters which can be read independently, comprise this book.
Division Plane Orientation in Plant Cells

This review discusses current knowledge on division plane determination in plant cells and how divisionwithin this plane is executed during cytokinesis. Plants cells are unusual among eukaryotes in that theirplanes of division are established prior to the onset of mitosis. Factors that contribute to the initialselection of the division plane include extra-cellular signals, cell geometry and polarity, and nuclearposition. During the G2 phase of the cell cycle, the formation of the preprophase band (PPB), a corticalassembly of microtubules and microfilaments, signals the future location of the division plane. Factorsimportant for PPB formation and maturation include the actin cytoskeleton, changes in microtubule dynamics,and protein dephosphorylation. Prior to its disassembly at prometaphase, the PPB functions in more thanone way to determine subsequent placement of the new cell wall. First, the PPB influences the initial orientationof the spindle, which facilitates subsequent cell wall formation within the division plane. Second, thePPB is thought to direct the formation of a cortical division site that persists after PPB breakdownand interacts during cytokinesis with the expanding phragmoplast, a cytoskeletal assembly that directsthe deposition of the partitioning cell wall. Both negative and positive cortical markers are implicatedin maintaining the memory of the former PPB site throughout mitosis and cytokinesis.
Prostate cancer diagnosis is associated with an increased risk of erectile dysfunction after prostate biopsy

What's known on the subject? and What does the study add? There have been several studies that have suggested there may be a relationship between prostate biopsy and erectile function and LUTS. Previous studies have suggested a specific association between the type of local anaesthesia administered and/or the number of biopsies performed. Other studies have suggested an exacerbation of LUTS after prostate biopsy. The present study identifies a positive cancer diagnosis as a novel characteristic that may explain a relationship between biopsy and worsening erectile function. Objective To evaluate prospectively the characteristics, erectile function and lower urinary tract symptoms (LUTS) of men undergoing prostate needle biopsy (PNBx). Patients and Methods From 2008 to 2011, 134 men were prospectively administered the International Index of Erectile Function (IIEF), American Urological Association Symptom Index (AUA-SI), and quality-of-life (QoL) questionnaires before and after undergoing a single 12-core PNBx. Comparisons of IIEF and AUA-SI scores before and after PNBx, based upon baseline characteristics and prostate cancer (PCa) diagnosis, were performed. Univariable and multivariable logistic regression models were used to characterize predictors of change in IIEF scores. Results In the 85 men who fulfilled the inclusion criteria, there were no significant differences between the mean (sd) total pre-biopsy and the mean (sd) post-biopsy IIEF scores: 57.8 (12.9) vs 54.3 (17.2). Subgroup analysis showed that men who had biopsy-proven PCa had significantly greater changes in their post-biopsy IIEF scores compared with men without (−10.1 vs. 1.0; P < 0.001). After specific analyses of the IIEF domains in these groups we found significant decreases in every domain, including erectile function (P = 0.01). On multivariate analyses, only PCa diagnosis was associated with a significant change in IIEF (odds ratio 7.2; P = 0.003). There were no differences in AUA-SI or QoL scores in the overall population or in subgroups. Conclusions Cancer diagnosis appears to have an adverse effect on the erectile function of men undergoing PNBx but no effect on LUTS. This study highlights a potential negative psychological confounder that may influence erectile function before the treatment of PCa. Additional prospective trials evaluating these relationships are warranted.
English and the class of context-free languages

Let L range over all natural languages (NLs). For any L, one can consider two collections of strings of symbols, one consisting of all strings over the terminal vocabulary of L, call it W*(L), the other consisting of that always very proper subcollection of W*(L) consisting of all and only those members of W*(L) that are well-formed, that is, that correspond to sentences of L. Call the latter collection WF(L). During the early development of generative grammar, a number of attempts were made to show, for various choices of L, that WF(L) was not a context-free (CF) string collection. These attempts all had, naturally, a common logical structure. First, it was claimed that there was some mathematical property P which, if possessed by some collection of strings, C, rendered C non-CF. Second, it was claimed that WF(C) had P, so the conclusion followed. Two sorts of criticisms can be, and have • been, directed at such attempted demonstrations. One attacks the mathematical foundations and argues, for particular choices of P, that a collection manifesting P is not necessarily not CF. The other type of criticism admits that if a collection manifests a particular property P, it is thereby not CF, but contends that the WF(L)s claimed to manifest P in fact don't. A survey of the various attempts, from roughly 1960 to 1982, to prove for various L that WF(L) is not CF is provided in Pullum and Gazdar (1982). These authors conclude, justifiably we believe, that for one or the other of the reasons mentioned above, none of these attempts, including those by the present authors, stand up. Despite widespread belief to the contrary, as of 1982 there had been no demonstration that there is some NL L for which W F ( L ) is not CF. 2 However, Langendoen and Postal (1984) have obtained a result infinitely stronger than the claim that for some L, WF(L) is not CF. This work shows that for any L, WF(L) is a proper class, hence not a set, much less a recursively enumerable set. There is thus no question of WF(L) being CF. Moreover, WF(L) can then have no constructive characterization (generative grammar), although there is no reason to doubt that it can be given a nonconstructive characterization. But the demonstration of Langendoen and Postal (1984) is based on principles that determine WF(L) includes nonfinite strings corresponding to nonfinite (transfinite) sentences. It is the existence of such sentences that places complete NLs beyond generative (constructive) characterization. Nevertheless, as noted in Langendoen and Postal (1984: 103), this novel result still leaves entirely open the question of whether that subpart of WF(L) consisting of all and only the well-formed finite strings in W*(L) is CF. Let F(inite)WF(L) be that subcollection of WF(L) consisting of all and only the finite strings corresponding to the finite sentences of L. What follows shows that there are dialects of English, E1 and E2, such that:
Cases, context, and comfort: opportunities for case-based reasoning in smart homes

Artificial intelligence (AI) methods have the potential for broad impact in smart homes. Different AI methods offer different contributions for this domain, with different design goals, tasks, and circumstances dictating where each type of method best applies. In this chapter, we describe motivations and opportunities for applying case-based reasoning (CBR) to a human-centered approach to the capture, sharing, and revision of knowledge for smart homes. Starting from the CBR cognitive model of reasoning and learning, we illustrate how CBR could provide useful capabilities for problem detection and response, provide a basis for personalization and learning, and provide a paradigm for home-human communication to cooperatively guide performance improvement. After sketching how these capabilities could be served by case-based reasoning, we discuss some design issues for applying CBR within smart homes and case-based reasoning research challenges for realizing the vision.
Further constraints on the pion-pion partial-wave amplitudes

A number of new constraint relations are obtained for the partial-wave amplitudes of pion-pion scattering.
Imagined Future in Chinese Novels at the Turn of the 21st century: A Study of Yellow Peril, The End of Red Chinese Dynasty and A Flourishing Age: China, 2013

Focusing on three influential contemporary Chinese political fantasy novels, this article contextualizes the stories in the complex spectrum of contemporary Chinese political thoughts and interprets them in light of the rivaling tendencies among the Chinese intellectuals since the 1990s, regarding the issues of rising nationalism and political authoritarianism, the possibilities of fascism and federalism, the role of a strong, centralized state, and the relevance of liberal democracy in China. The article calls attention to fiction as an expression of political thought and concerns, and argues that these novels present a pessimistic and chilling view of China’s political future, in contrast with the optimistic tone of novels of the same genre in the early 20 th century, and also challenge an earlier cult of the Western model of liberal democracy. An earlier Chinese-language version of the paper appeared in the website “Democratic ChinaC”, http://www.minzhuzhongguo.org 12/8/2010, entitled “Zhengzhi huanxiang xiaoshuo zhong de dangdai Zhongguo sixiang: jiedu Huang Huo, Zhongnanhai zuihou de douzheng, he Shengshi, Zhongguo 2013” [Chinese Political Thought as Reflected in Political Fantasy Novels: Interpreting Yellow Peril , The End of Red Chinese Dynasty , and A Flourishing Age: China, 2013
The Influence of Curvature on Stress Intensity at the Tip of a Circumferential Crack in a Cylindrical Shell

Curvature effect on cylindrical shell circumferential crack tip stress intensity, using fatigue crack growth tests
Economic Growth, Income Distribution and Agricultural Policy in Malawi

Malawi's weak economic performance during the 1980s occurred in part due to the failure to reform agricultural pricing policies. An econometric model shows that the continuation of high levels of taxation on small-holder exports slowed the growth of the economy and hurt the poor. While a policy of adhering to border prices is therefore commended, the model also shows that raising minimum wages in the absence of productivity gains will erode the benefits of price liberalization. Furthermore, price policy reforms need to be accompanied by broader institutional reforms, particularly those aimed at breaking down the imposed market segmentation between estates producers and small-holders. Copyright 1994 by Oxford University Press.
Broadband phase-matched generation and detection of terahertz radiation

We discuss advances in the optoelectronic generation and detection of coherent terahertz radiation. The demonstrations utilize poled polymeric media, which exhibit characteristics that are extremely well suited for broadband THz applications. Using a 35 mm thick poled polymer film, we demonstrate electro-optic detection of freely propagating ultrashort baseband electromagnetic pulses with spectral sensitivity that extends from the far-infrared (l ~ 100 μm) to ~33 THz (l = 9 μm). Over a band of nearly 20 THz, a relatively flat frequency response is observed. We compare the performance of the poled polymer with that of established materials. We also present a novel waveguide geometry that allows for the phase-matched generation of broadband THz radiation in a polymer-based parallel plate metal waveguide via optical rectification. Both the optical pump beam and the generated THz radiation propagate in the fundamental mode of the waveguide. This allows for non-critical phase matching over a broad range of THz frequencies. We demonstrate guided wave interaction lengths of up to 3 mm.
Backtrack-Based Failure Recovery in Distributed Stream Processing

Since stream analytics is treated as a kind of cloud service, there exists a pressing need for its reliability and fault-tolerance. In a streaming process, the parallel and distributed tasks are chained in a graph-structure with each task transforming a stream to a new stream, the transaction property guarantees the streaming data, called tuples, to be processed in the order of their generation in every dataflow path, with each tuple processed once and only once. The failure recovery of a task allows the previously produced results to be corrected for eventual consistency, which is different from the instant consistency of global state enforced by the failure recovery of general distributed systems, and therefore presents new technical challenges. Transactional stream processing typically requires every task to checkpoint its execution state, and when it is restored from a failure, to have the last state recovered from the checkpoint and missing tuple re-acquired and processed. Currently there exist two kind approaches: one treats the whole process as a single transaction, and therefore suffers from the loss of intermediate results during failures, the other relies on the receipt of acknowledgement (ACK) to decide whether moving forward to emit the next resulting tuple or resending the current one after timeout, on the per-tuple basis, thus incurs extremely high latency penalty. In contradistinction to the above, we propose the backtrack mechanism for failure recovery, which allows a task to process tuples continuously without waiting for ACKs and without resending tuples in the failure-free case, but to request (ASK) the source tasks to resend the missing tuples only when it is restored from a failure which is a rare case thus has limited impact on the overall performance. We have implemented the proposed mechanisms on Fontainebleau, the distributed stream analytics infrastructure we developed on top of Storm. As a principle, we ensure all the transactional properties to be system supported and transparent to users. Our experience shows that the ASK-based recovery mechanism significantly outperforms the ACK-based one.
Substantial Powers, Active Affects: The Intentionality of Objects

What can Dungeons & Dragons teach us about the being of beings? This article argues that Dungeons & Dragons introduces us to a world composed of objects or entities, where the being of objects is defined not by their qualities, but rather by their powers, capacities or affects. Drawing on the thought of Spinoza, Deleuze and Molnar, objects are seen to be defined by what they can do or their capacities to act, such that qualities are effects of these acts. Dungeons & Dragons is particularly suited to showing us this insofar as it focuses on the action of entities.
An All Wiggler and Undulator Synchrotron Radiation Source

Successful experience with wiggler and undulator (w/u) magnets as synchrotron radiation (SR) sources has led to new facility design concepts. We review the design features and performance criteria of new rings and describe a proposed facility at SLAC consisting of two rings (1-2 and 5-6 GeV) in the same tunnel, both optimized for w/u insertions. We also present conceptual designs for permanent magnet dipoles and quads.
The temperature dependences of some types of gaseous ionic reactions of astrochemical interest.

The rate constants of ion-molecule reactions which are of potential significance in astrochemical systems are found to exhibit significant, and in many cases, negative temperature dependences. The rate constants of fast ion-polar molecule reactions (e.g., XH++B»BH++X) may increase by a factor of 5–10 between 1000 and 10K. Slow reactions that proceed via reaction complexes (e.g., H-transfer and association reactions) often exhibit temperature dependences of the formk=AT −n ,n=1–5. Both transition state theory considerations and the coupled-oscillator RRK-type model are seen to be able to account qualitatively for the behavior of slow ion-molecule, reactions.
On the Nature of Teaching Nature of Science: Preservice Early Childhood Teachers' Instruction in Preschool and Elementary Settings

This study explored whether early childhood preservice teachers' concerns about teaching nature of science (NOS) and their intellectual levels influenced whether and how they taught NOS at the preschool and primary (K-3) levels. We used videotaped classroom observations and lesson plans to determine the science instructional practices at the preschool and primary levels, and to track whether and how preservice teachers emphasized NOS. We used the Stages of Concern Questionnaire (SOCQ) pre- and postinternship to determine concerns about NOS instruction, and the Learning Context Questionnaire (LCQ) to determine intellectual levels. We found that neither concerns about teaching NOS nor intellectual level were related to whether and how the preservice teachers emphasized NOS; however, we found that all preservice early childhood teachers began their internships with NOS concern profiles of “worried.” Two preservice teachers' NOS concerns profiles changed as a result of their internships; one to “cooperator” and one to “cooperator/improver.” These two preservice teachers had cooperating teachers who were aware of NOS and implemented it in their own science instruction. The main factors that hindered or facilitated teaching NOS for these preservice teachers were the influence of the cooperating teacher and the use of the science curriculum. The preservice teacher with the cooperating teacher who understood and emphasized NOS herself and showed her how to modify the curriculum to include NOS, was able to explicitly teach NOS to her students. Those in classrooms whose cooperating teachers did not provide support for NOS instruction were unable to emphasize NOS. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 47:213–233, 2010
Identification of a 32K plasma membrane protein that binds to the myristylated amino-terminal sequence of p60v-src

THE transforming protein of Rous sarcoma virus, p60v-src, is a myristylated membrane-bound phosphoprotein1–3. Interaction of p60v-src with the plasma membrane is essential for transforming activity4–5, and is mediated by association with a membrane-bound Src receptor protein6. Evidence for the existence of an Src receptor is based on the ability of a myristylated peptide containing the N-terminal Src sequence to inhibit binding of p60v-src to plasma membranes in vitro: binding of p60v-src to a plasma membrane receptor is therefore mediated by N-terminal Src sequences6. Here we report that a myristyl-Src peptide, but not the corresponding non-myristylated peptide, can be specifically crosslinked to a plasma membrane protein of relative molecular mass 32,000 (Mr 32K). The 32K protein represents an Src-binding protein in the plasma membrane that is likely to be a component of the myristyl-Src receptor, and which could be involved in cellular transformation.
Deletion mutation in the signal anchor domain activates cleavage of the influenza virus neuraminidase, a type II transmembrane protein

Influenza virus neuraminidase (NA) is a type II integral membrane protein with a long hydrophobic domain [29 amino acids (aa)] at the N terminus that functions as an uncleaved signal for translocation into the endoplasmic reticulum and anchors the protein in the membrane. The function of the transmembrane domain in intracellular transport was investigated by deletion mutagenesis. Expression of the mutated NA in eukaryotic cells and by in vitro translation in the presence of membranes showed that the deletion of eight amino acids (aa 28 to 35) from the carboxy end of the signal anchor domain resulted in cleavage, probably by the signal peptidase and secretion of NA into the culture medium. The mutant NA (N28-35) was present inside the cell predominantly as dimers, secreted as dimers, and was enzymatically inactive. When translated in vitro in the presence of dog pancreatic microsomal membranes, the N28-35 protein underwent cleavage and did not remain anchored to membranes. Two other deletion mutants in the transmembrane domain, N7-17 and N17-23, were partially cleaved and secreted, whereas two mutants, one (N19-27) lacking nine aa in the central region and the other (N1-14) lacking the first 14 aa from the N terminus remained uncleaved and exhibited a phenotype similar to the wild-type NA. We conclude that the longer transmembrane domain (29 aa) may play an important role in determining that type II signal is not cleaved during translocation; however, in addition, adjacent amino acid sequences also provide determinants important in signal cleavage.
Photoelectrochemical Behavior of n-GaAs and n-AlxGa1-xAs in CH3CN

Current density vs potential, open-circuit voltage vs temperature, and differential capacitance vs potential measurements have been used to show that n-GaAs and n-AlxGa1-xAs electrodes exhibit partial Fermi level pinning in contact with CH3CN over a wide range of redox potentials. Despite a change of over 1.2 V in redox potential of the solution, the open-circuit voltage only changed by ∼300 mV. The slope of the open-circuit voltage vs redox potential of the solution was typically 0.33−0.44. Differential capacitance vs potential data also yielded a barrier height change of less than 300 mV for over 1.2 V change in the redox potential of the solution. The dependence of the current density vs potential behavior of n-GaAs/CH3CN−ferricenium−ferrocene+/0 on variables such as the illumination intensity, dopant density of the semiconductor, concentration of redox acceptor in the solution, crystal face, electrolyte, and cell temperature was evaluated. The resultant kinetic data indicate that surface-state recombi...
A multilevel framework for linear projection constraints

Modified preconditioned Conjugate Gradient (MpCG) [Baraff and Witkin 1998] is a well known single level solver to implicitly handle linear projection constraints. In this work we propose a novel multilevel framework to implicitly handle linear projection constraints. Our method has multiple advantages: (a) faster (and guaranteed) convergence compared to MpCG (b) ease of integration into existing multilevel codes and (c) minimal overhead cost to incorporate constraints. Linear projection constraints are used in many aspects of the simulation such as internal articulation constraints, external Dirichlet boundary conditions [Arikatla and De 2013], initial projection during collision handling and interactive user manipulation.
Effects of support on bifunctional methanol oxidation pathways catalyzed by polyoxometallate Keggin clusters

Abstract H 5 PV 2 Mo 10 O 40 polyoxometallate Keggin clusters supported on ZrO 2 , TiO 2 , SiO 2 , and Al 2 O 3 are effective catalysts for CH 3 OH oxidation reactions to form HCHO, methyl formate (MF), and dimethoxymethane (DMM). Rates and selectivities and the structure of supported clusters depend on the surface properties of the oxide supports. Raman spectroscopy showed that Keggin structures remained essentially intact on ZrO 2 , TiO 2 , and SiO 2 after treatment in air at 553 K, but decomposed to MoO x and VO x oligomers on Al 2 O 3 . Accessible protons per Keggin unit (KU) were measured during CH 3 OH oxidation by titration with 2,6-di- tert -butyl pyridine. For similar KU surface densities (0.28–0.37 KU/nm 2 ), the number of accessible protons was larger on SiO 2 than on ZrO 2 and TiO 2 and much smaller on Al 2 O 3 supports, even though residual dimethyl ether (DME) synthesis rates after titrant saturation indicated that the fractional dispersion of KU was similar on the first three supports. These effects of support on structure and on H + accessibility reflect varying extents of interaction between polyoxometallate clusters and supports. Rates of CH 3 OH oxidative dehydrogenation per KU were higher on ZrO 2 and TiO 2 than on SiO 2 at similar KU surface densities (0.28–0.37 KU/nm 2 ) and dispersion, indicating that redox properties of Keggin clusters depend on the identity of the support used to disperse them. ZrO 2 and TiO 2 supports appear to enhance the reducibility of anchored polyoxometallate clusters. Rates were much lower on Al 2 O 3 , because structural degradation led to less reactive MoO x and VO x domains. CH 3 OH reactions involve primary oxidation to form HCHO and subsequent secondary reactions to form DMM and MF. These reactions involve HCHO–CH 3 OH acetalization steps leading to methoxymethanol (CH 3 OCH 2 OH) or hemiacetal intermediates, which condense with CH 3 OH on acid sites to form DMM or dehydrogenate to form MF. CO x formation rates are much lower than those of other reactions, and DME forms in parallel pathways catalyzed by acid sites. Secondary reactions leading to DMM and MF are strongly influenced by the chemical properties of support surfaces. Acidic SiO 2 surfaces favored DMM formation, while amphoteric or dehydrogenating surfaces on ZrO 2 and TiO 2 led to MF formation, as a result of the varying role of each support in directing the reactions of HCHO and CH 3 OH and of the CH 3 OCH 2 OH intermediates toward DMM or MF, which was confirmed using physical catalyst–pure support mixtures. These support effects reflect the bifunctional pathways of CH 3 OH reactions. These pathways are consistent with the effects of residence time and of the partial removal of H + sites by titration using 2,6-di- tert -butyl pyridine.
THE NITROSYL AZIDE POTENTIAL ENERGY HYPERSURFACE : A HIGH-ENERGY-DENSITY BOOM OR BUST ?

Motivated by the recent isolation and spectroscopic characterization of nitrosyl azide (N4O), we have undertaken an ab initio investigation of the originally reported structure as well as various structural isomers on the potential energy hypersurface. Geometries and harmonic vibrational frequencies have been predicted for the trans-chain isomer along with the 6 π electron potentially aromatic ring structure with various levels of theory up through the triple-ζ plus double polarization single and double excitation coupled cluster (TZ2P CCSD) method and the multireference configuration interaction method (MRCISD). In addition, estimates are made for extension to higher levels of theory, arriving at final predictions of re(ON1) = 1.176 A, re(N1N2) = 1.472 A, re(N2N3) = 1.272 A, re(N3N4) 1.423, ϑe(N1ON4) = 106.3° for the trans-chain and ring isomers, respectively. Energy relationships, b...
Schur complements, Schur determinantal and Haynsworth inertia formulas in Euclidean Jordan algebras

In this article, we study the concept of Schur complement in the setting of Euclidean Jordan algebras and describe Schur determinantal and Haynsworth inertia formulas.
A fast algorithm for electrically small composite objects

Extensive studies have been conducted by many researchers on low-frequency or electrically small problems using the surface integral equation (SIE) method. However, it does not appear in the literature that problems with a large number of unknowns in this area can be solved efficiently. The paper presents a multi-tree scheme to apply the low-frequency multilevel fast multipole algorithm (LF-MLFMA) to composite objects, so that O(N) CPU time and memory usage is obtained. A new implementation of basis rearrangement is also presented to make the algorithm stable and capable of solving problems with a large number of unknowns.
The effect of the N-acyl moiety of the substrate on α-chymotrypsin binding and catalysis

Abstract The effect of the N-acyl moiety of the substrate on α-chymotrypsin binding and catalysis of N-carbomethoxy-, N-formyl-, N-acethyl-,N-chloroacetyl-, N-methanesulfonyl- and unacylated L-tyrosine ehtyl esters was studied. Pre-steady-state and steady-state kinetics of the α-chymotrypsin- catalyzed hydrolysis of L-tyrosine ethyl ester indicated that deacylation is the rate-limiting step at pH 7. However, at pH 5 rates of acylation and deacylation were approximately equal. The rates of deacylation of the various acyl—chymotrypsins, formed as intermediates with the above substrates, correlated with the hydrogen-bonding ability of the N-acyl substituent. However, the rates of acylation of a α-chymotrypsin by these substrates did not correlate with the hydrogen-bonding ability of the N-acyl substituent but showed some correlation with the ability of the substrate to undergo azlactone formation. The dissociation constants of the various substrates with the enzyme do not correlate with the hydrophobicity, molar refractivities or pKa of the parent acid of the N-acyl group, indicating that other portions of the substrate play a major role in binding also.
Coherent-feedback control in nanophotonic circuits

The emerging discipline of coherent-feedback quantum control provides core concepts and methods for nanopho- tonic circuit theory, which can be assimilated within modern approaches to computer-aided design. Current research in this area includes the development of software tools to enable a schematic capture workflow for compilation and analysis of quantum stochastic models for nanophotonic circuits, exploration of elementary coherent-feedback circuit motifs, and laboratory demonstrations of quantum nonlinear photonic devices.
Effects of early postnatal ethanol intubation on GABAergic synaptic proteins.

Fetal alcohol syndrome includes brain damage from aberrant synaptogenesis, altered cell–cell signaling and blunted plasticity in surviving neurons. Distortion of neurotrophic GABA signals by ethanol-mediated allosteric modulation of GABAA receptor (GABAAR) activity during brain maturation may play a role. In this regard, early postnatal binge-like ethanol treatment on postnatal days (PDs) 4–9 acutely inhibits whole cell GABAAR Cl− current and subsequently blunts GABAAR function in medial septum/diagonal band (MS/DB) neurons and cerebellar Purkinje cells [Dev. Brain Res. 130 (2001) 25–40; Brain Res. 810 (1998) 100–113; Brain Res. 832 (1999) 124–135]. In light of these functional changes, we hypothesized that ethanol treatment also would decrease levels of proteins important for assembly of GABAergic synapses in maturing brain. To test this relationship, binge-like ethanol intubation was administered to rat pups on PDs 4–9 producing peak blood ethanol concentrations in the range of 302.5±6.3 mg/dl. GABAergic synaptic proteins were measured in brain tissue on PDs 13–14 when GABAAR currents in individual MS/DB neurons are reduced, but those of cerebellar Purkinje neurons are not yet altered [Dev. Brain Res. 130 (2001) 25–40; Brain Res. 810 (1998) 100–113; Brain Res. 832 (1999) 124–135]. Surprisingly, ethanol did not decrease protein levels of GABAAR α1/β2 subunits, GAD67 or gephyrin in MS/DB at this time when whole cell recordings indicate GABAAR function is impaired in acutely dissociated individual neurons. However, in cerebellum where ethanol treated Purkinje cell GABAAR function remains normal on PDs 13–14 [Brain Res. 832 (1999) 124–135], reduced levels of several GABAergic synaptic proteins including: GAD67, GABAAR α1 subunit, ClC-2 a voltage-gated Cl− channel, synaptotagmin a synaptic vesicle protein, and N-cadherin, a synapse associated cell adhesion molecule, were found. These results indicate that binge-like ethanol exposure differentially decreases GABAergic synaptic proteins in some brain areas in a pattern that does not parallel reductions in GABAAR function of individual neurons that survive this ethanol insult.
Circulation of cortical and thalamic neuronal activity in wakefulness and in sleep

Abstract The present study has attempted to determine, by quantitative methods, the changes which occur in the circulation of neuronal activity, in the cerebral cortex and in the thalamus, in the transition from wakefulness to slow wave sleep and to paradoxical sleep. Gross waves and neuronal activity have been recorded by means of arrays of extracellular microelectrodes from the cortex and the thalamus of unrestrained, unanesthetized cats. Autocorrelations have been performed on trains of rhythmic gross waves. Cross correlations have been performed between waves and neuronal activity and between trains of action potentials generated by different groups of neurons. It has been found that: (1) the circulation of activity develops and remains consistent for long periods in all states of wakefulness or sleep; (2) as the rhytmicity of the gross waves changes in the transition from one state to another, so do the characteristics of the circulation; however, the time and phase relations between the activities of the groups of neurons involved in circulation, maintain a high degree of correlation in all the states of wakefulness of sleep and (3) in the states of wakefulness and paradoxical sleep the cortical and thalamic activities are, frequently, infiltrated by rhythmicities of the theta range; when this occurs, the time and phase relations between the gross waves and the circulating neuronal activity show that the infiltrating theta rhythm develops within the cortex or the thalamus and is based on the activity of local networks.
Fabric Stratification Manifolds for Solar Water Heating

The level of thermal stratification that can be maintained in forced-flow, direct solar water-heating systems using a fabric manifold is studied in a 372-liter tank with an inlet flow rate of 0.07 1/s. A rib-knit, lightweight, spun-orlon acrylic is the most effective manifold material in a comparative study of 13 synthetic and natural fabrics. Thermal stratification (or more appropriately mixing) in the tank equipped with this acrylic manifold is compared to the level of stratification achieved using a rigid, porous manifold and a conventional drop-tube inlet. Initial tank temperature profile, temperature of the water entering the tank, and test duration are varied in three testing schemes. Comparison of vertical temperature profiles and height-weighted energy stored in the tank indicate that under realistic operating conditions, the fabric manifold is 4 percent more effective than the rigid manifold, and 48 percent more effective than the conventional drop-tube inlet.