cssi/SciSciGPT-SciSciNet huggingface dataset:
Innovative 3D integration of power MOSFETs for synchronous buck converters

Efficiency and power loss in the microelectronic devices is a major issue in power electronics applications. The engineers are challenged every year to increase power density and at the same time reduce the amount of power dissipated in the applications to keep the maximum temperatures under specifications. This situation drives a constant demand for better efficiencies in smaller packages. Traditional approaches to improve efficiency in DC/DC synchronous buck converters include reducing conduction losses in the MOSFETs through lower RDS(ON) devices and lowering switching losses through low-frequency operation. However the incremental improvements in RDS(ON) are at a point of diminishing returns and low RDS(ON) devices have large parasitic capacitances that do not facilitate the high-frequency operation required to improve power density. The drive for higher efficiency and increased power in smaller packages is being addressed by advancements in both silicon and packaging technologies. The NexFET Power Block combines these two technologies to achieve higher levels of performance, and in half the space versus discrete MOSFETs. This article explains these new technologies and highlights their performance advantage.
Microarray Experiment Design and Statistical Analysis

Microarray technology is a new kid on the block for biological researchers, and it has shown a great potential in many fields. While biologists are thrilled by the power of this new technology, they are also over-whelmed by the enormous amount of data generated, and often feel uncomfortable about how to extract useful information from the data. On one hand, there is always some information to be mined in such big data sets; on the other hand, it is almost certain that spurious findings will result even if extreme care has been exercised in mining the data. This challenge mandates interdisciplinary cooperation among biologists, statisticians and computer scientists. Although research in this area is still in its infancy, it is our goal in this chapter to discuss some of the most prominent issues in experiment design and statistical analysis for microarray research and to present possible solutions to some of these problems.
The Covariant Surface Derivative

In the preceding chapter, we gave an overview of embedded surfaces. We now turn to the important question of covariant differentiation on the surface. We will divide the construction of the covariant derivative into two parts. We will first define this operator for objects with surface indices. The definition will be completely analogous to that of the covariant derivative in the ambient space. While the definition will be identical, some of the important characteristics of the surface covariant derivative will be quite different. In particular, surface covariant derivatives do not commute. Our proof of commutativity for the ambient derivative was based on the existence of affine coordinates in Euclidean spaces. Since affine coordinates may not be possible on a curved surface, that argument is no longer available. We will also discover that the surface covariant derivative is not metrinilic with respect to the covariant basis S α. This will prove fundamental and will give rise to the curvature tensor, which will be further developed in Chap. 12
The antiarrhythmic and cardiovascular properties of 1-dimethyl isopropylamino-3-(2-phenylphenoxy)-propan-2-ol chloride, UM-424.

The quarternary ammonium compound, UM-424 [1-dimethyl isopropylamino-3-(2-phenylphenoxy)-propan-2-ol chloride], was evaluated for its antiarrhythmic and hemodynamic effects. UM-424 converted ouabain-induced ventricular tachycardia in the anesthetized dog when administered in an average dose of 4.6 mg/kg i.v. Pretreatment of anesthetized dogs with UM-424, 10 mg/kg, provided complete protection against the development of premature beats and ventricular fibrillation when the left anterior descending coronary artery was occluded for 20 minutes and then released. UM-424 was effective in reversing ventricular arrhythmias in conscious animals which had been subjected to a two-stage ligation of the anterior descending coronary artery. The mean ectopic rate in a group of five dogs was 143 +/- 4.0 (S.E.M.) beats/min 24 hours after coronary ligation. Normal sinus rhythm was restored with a mean dose of 9.5 mg/kg of UM-424 and was maintained for a period in excess of 60 minutes. The ventricular fibrillation threshold was increased from a control value of 4.0 +/- 0.4 to 26.2 +/- 8.6 mA (P less than .05) 30 minutes after pretreatment with UM-424, 10 mg/kg. Inotropic and chronotropic dose-response studies to isoproterenol in the anesthetized dog demonstrated that the quarternary compound lacked beta adrenergic receptor blocking properties. UM-424, 10 mg/kg, did not produce any persistent changes in spontaneous heart rate, cardiac contractile force, left ventricular dP/ct, mean arterial blood pressure, cardiac output and mean pulmonary arterial pressure.
The design of a control law for rotating stall in an axial compressor

Presented in this paper is the design of a control law for rotating stall in axial compressors. The controller design is executed in two primary phases. In the first phase, an input-output model of the compressor is developed to recover the frequency response of the spatial mode dynamics. The representation of the compressor dynamics in this form facilitates the controller design process. In the second phase, a feedback controller having the structure Ui = Kieifcyi is designed to maximize the stability of the i spatial mode where yi denotes the i spatial harmonic. Maximum performance is limited by the output saturation of the air injectors. The design of Ki and ft is realized using a feedback control notion referred to as sensitivity. Sensitivity is a measure of the transmissibility of the disturbances which lead to rotating stall. The controller is designed for an analytical compressor model comprised of nonlinear ordinary differential equations (NODE). These NODEs are derived from a reduction of the Moore-Greitzer partial differential equations (PDE). The paper concludes with a discussion of designing dynamic controllers which may achieve performance beyond the control law
Counterpropagating nondiffracting vortex beams with linear and angular momenta

Closed-form analytical expressions for the electric and magnetic (EM) field components of a high-order Bessel vortex beam of fractional type \ensuremath{\alpha} (HOBVB-F\ensuremath{\alpha}) are derived based on the axial polarization of the vector potentials [denoted by ($z,\ensuremath{-}z$)]. The fields' components correspond to the most generalized case of quasi-standing-waves that reduce to perfect (i.e., equiamplitude) standing waves or progressive waves with appropriate choice of the quasi-standing-wave coefficient $0\ensuremath{\le}\ensuremath{\Upsilon}\ensuremath{\le}1$. The beam components are exact solutions of the vector wave equation (Helmholtz equation) and Maxwell's equations. Moreover, computations of the EM components and comparison with the results obtained from a transverse polarization scheme [denoted by (x,\ensuremath{-}y)] illustrate the analysis. In addition, the time-averaged angular momentum density and flux are evaluated with particular emphasis on the axial and transverse polarization states of the vector potentials. It is found that the quasi-standing-wave effect does not influence the spatial distributions of the EM components in the transverse polarization scheme (x,\ensuremath{-}y); however, it affects the transverse EM field components in the axial polarization (z,\ensuremath{-}z). Moreover, both the linear and angular momenta density fluxes are shown to reverse sign for a particular value of the half-cone angle \ensuremath{\beta}. These phenomena anticipate the production of a ``tractor'' beam where particulate matter may be pulled back toward the source, and a spinning reversal effect in which particulate matter may rotate with opposite handedness to a HOBVB-F\ensuremath{\alpha}. The results are particularly useful in applications involving optical laser tweezers, tractor beams, optical spanners, arbitrary scattering, radiation force, angular momentum, and torque.
Sugar-induced aging: the deleterious effects of excess dietary sugar intake.

Scientists define aging as the progressive accumulation of deleterious changes on the biochemical and cellular levels over a period of time that leads to dysfunction of an organism on the cell, tissue, and organ levels that eventually increases the risk of disease and death with advancing age.1 The
The GIRK1 subunit potentiates G protein activation of cardiac GIRK1/4 hetero-tetramers

G protein gated inward rectifier potassium (GIRK) channels are gated by direct binding of G protein beta-gamma subunits (Gβγ), signaling lipids, and intracellular Na(+). In cardiac pacemaker cells, hetero-tetramer GIRK1/4 channels and homo-tetramer GIRK4 channels play a central role in parasympathetic slowing of heart rate. It is known that the Na(+) binding site of the GIRK1 subunit is defective, but the functional difference between GIRK1/4 hetero-tetramers and GIRK4 homo-tetramers remains unclear. Here, using purified proteins and the lipid bilayer system, we characterize Gβγ and Na(+) regulation of GIRK1/4 hetero-tetramers and GIRK4 homo-tetramers. We find in GIRK4 homo-tetramers that Na(+) binding increases Gβγ affinity and thereby increases the GIRK4 responsiveness to G protein stimulation. GIRK1/4 hetero-tetramers are not activated by Na(+), but rather are in a permanent state of high responsiveness to Gβγ, suggesting that the GIRK1 subunit functions like a GIRK4 subunit with Na(+) permanently bound.
In Vitro Culture and Germination of Terrestrial Asian Orchid Seeds

Orchidaceae is one of the largest families of flowering plants, and many of its species are highly valuable as herbal medicines and to the horticultural industry. To meet commercial requirements and to conserve natural resources, in vitro seed germination has been utilized to produce large quantities of uniform seedlings. In general, terrestrial orchid seeds are more difficult to germinate and grow than epiphytic orchids. Terrestrial orchid seeds have a hardened seed coat and more stringent requirements for germination in vitro. In this chapter, we document the timing of seed collection and pretreatments for improving in vitro germination of some terrestrial Asian orchids. The process of in vitro germination is demonstrated, including (1) the culture of immature seeds; (2) the culture of mature seeds; and (3) subsequent seedling development. For immature seed culture, optimal timing of seed harvest is key to maximizing germination; for mature seed culture, selection of adequate pretreatment conditions (i.e., the duration and concentrations of pretreatment solutions) is essential to improve germination.
Failed Intussusception Reduction in Children: Correlation Between Radiologic, Surgical, and Pathologic Findings.

OBJECTIVE. The objective of this study was to identify causes of irreducible intussusception after contrast enema and to correlate imaging findings with surgical and histopathologic findings. MATERIALS AND METHODS. Between 2005 and 2013, a total of 543 children underwent reduction of intussusception with the use of an enema technique (hereafter referred to as “enema reduction”). The medical records of 72 children (56 boys [mean age, 24.8 months; range, 3.8 months to 10.9 years] and 16 girls [mean age, 14.2 months; range, 1.5 months to 6.9 years) who underwent unsuccessful reduction and were treated surgically were retrospectively analyzed. The data collected included information on the cause of intussusception, the risk factors noted on ultrasound, operative management, outcome, and the length of the hospital stay. The imaging findings for these patients were compared with findings for statistically similar age-matched control subjects. RESULTS. Ultrasound detected 56 of 57 cases of intussusception, but i...
Acute care patient portals: a qualitative study of stakeholder perspectives on current practices.

Objective To describe current practices and stakeholder perspectives of patient portals in the acute care setting. We aimed to: (1) identify key features, (2) recognize challenges, (3) understand current practices for design, configuration, and use, and (4) propose new directions for investigation and innovation. Materials and Methods Mixed methods including surveys, interviews, focus groups, and site visits with stakeholders at leading academic medical centers. Thematic analyses to inform development of an explanatory model and recommendations. Results Site surveys were administered to 5 institutions. Thirty interviews/focus groups were conducted at 4 site visits that included a total of 84 participants. Ten themes regarding content and functionality, engagement and culture, and access and security were identified, from which an explanatory model of current practices was developed. Key features included clinical data, messaging, glossary, patient education, patient personalization and family engagement tools, and tiered displays. Four actionable recommendations were identified by group consensus. Discussion Design, development, and implementation of acute care patient portals should consider: (1) providing a single integrated experience across care settings, (2) humanizing the patient-clinician relationship via personalization tools, (3) providing equitable access, and (4) creating a clear organizational mission and strategy to achieve outcomes of interest. Conclusion Portals should provide a single integrated experience across the inpatient and ambulatory settings. Core functionality includes tools that facilitate communication, personalize the patient, and deliver education to advance safe, coordinated, and dignified patient-centered care. Our findings can be used to inform a “road map” for future work related to acute care patient portals.
Squeaky Wheels and Troop Loyalty: How Domestic Protests Influence Coups d’état, 1951–2005

This article considers how domestic protests influence coups. Protests signal regime illegitimacy, which incentivizes coups and provides a favorable climate for postcoup reforms. Protests also ease coordination obstacles among coup plotters and make international actors less likely to punish coup leaders. We expect these signaling processes to be strongest when protests take place near the capital or are nonviolent. Our empirical analyses introduce event-level protest data from the Social, Political, and Economic Event Database project into the coup literature. Examining a global sample of coup attempts from 1951 to 2005, we find strong support for our theoretical expectations. Our discussion provides implications for scholars studying coups and nonviolent movements more generally. It also speaks to the influence of external actors on social uprisings and highlights the importance of geographical disaggregation in the study of dissident behavior.
Greedy Prefix Cache for IP Routing Lookups

As the rapid growth of Internet and the communication link speed, it becomes increasingly challenging for network processors to timely route the incoming traffic to the destination ports. The traditional approach must look up the routing table based on the destination IP address to determine the output port. The ternary CAM approach provides fast associative look up, but is very costly for large routing tables. The trie-based algorithm allows inexpensive searching, but may not satisfy the growing speed requirement. Previous studies showed that the overall routing time can be shortened by adding a small prefix cache for the general trie-based routing algorithms. In caching the prefix, however, the nested prefixes are difficult to cache due to the constraint of the longest prefix matching requirement. This paper presents a greedy prefix caching technique to improve the prefix cache performance that allows caching the largest sub-tree of each prefix including the parent prefixes. Our experiment results show that the prefix cache using the proposed upgrade scheme can reduce the miss ratio by about 6-8% comparing to the best existing prefix caching mechanism.
Silicon Microsensors: Construction, Design and Performance

Sensors are devices which convert non-electronic variables to currents or voltages. They become microsensors when they are fabricated by modified integrated circuit techniques. Microsensors fall into two classes: replacements for existing devices with physically smaller, higher performance and lower cost structures; and novel sensors which can only be constructed by using micromechanics. These ideas can be illustrated by the results of a major effort in surface micromachined pressure transducers which started with the goal of producing designable, economicaly viable absolute pressure sensors with a scaling reduction factor of at least 100 over existing devices. Since an absolute pressure transducer consists of a vacuum sealed pill box which deforms with applied pressure and a sensing scheme which converts deformation with applied pressure to electronic signals, reliable pill box construction must be addressed first. Mechanical considerations in conjunction with the desired scaling lead to the conclusion that a pill box wall thickness of roughly 2 micrometers would be required. This implies the use of thin films and because of thermal consideration leads to the selection of polysilicon as the most attractive film for pill box construction. High packing densities, a requirement for novel sensors, leads to a pill box construction technique which uses surface micromachining with silicon dioxide as a sacrificial layer which is etched laterally as the technology of choice. This choice becomes defendable if the mechanical properties of polysilicon can be determined and if process design can be implemented to produce repeatable, predetermined built-in strain, Young's modulus, and tensile strength.
Poor Survival of CD34 Positive and CD13/33 Positive Patients in Pediatric T-Cell Acute Lymphoblastic Leukemia Is Not Explained by Expression of Multidrug Resistance Genes.

Abstract For childhood T-ALL, the significance of early differentiation markers CD34 and CD13/33 in relation to outcome is unclear. In this study of 72 pediatric T-ALL patients, CD34 and CD13/33 expression was related to a poor 5 yrs survival (p=0.0013 for CD34+ and p=0.035 for CD33/CD13+). Expression of CD34 was associated with elevated MDR1 (p=0.01) and MRP1 (p=0.019) levels and CD13/33+ expression with MRP1 levels (p=0.028). However, none of these MDR genes independently predicted for poor outcome. We conclude that T-ALL with CD34 and CD13/33 expression has a relatively poor survival that is not explained by expression of MDR genes.
Comprehensive Assessments of the Effects of Auditory Cognitive Distractions on Driving Safety Across the Lifespan

Inexperienced younger (29), middle-aged (29), and older drivers (25) participated in a study evaluating the effects of auditory cognitive distractions on driving safety. Unlike prior research, the secondary tasks were typical of everyday behavior such as listening to a story and participating in a radio quiz. The study also examined driving performance more broadly than prior studies. Outcome measures included speed and lateral control similar to prior studies but in addition included headway maintenance, mean headway time, gap acceptance, mirror use, proper signaling, stopping behavior, intersection scanning. Performance was evaluated in a wider range of driving tasks than prior studies (e.g. included gap tasks such as lane changes, freeway merges, left turns in addition to straightaway car-following). Results showed that older drivers were affected the most by these distractions and that performance was often degraded beyond speed and lateral control to include signaling, mirror use, intersection scanning behaviors.
Bacterial artificial chromosomes establish replication timing and sub-nuclear compartment de novo as extra-chromosomal vectors

The role of DNA sequence in determining replication timing (RT) and chromatin higher order organization remains elusive. To address this question, we have developed an extra-chromosomal replication system (E-BACs) consisting of ∼200 kb human bacterial artificial chromosomes (BACs) modified with Epstein-Barr virus (EBV) stable segregation elements. E-BACs were stably maintained as autonomous mini-chromosomes in EBNA1-expressing HeLa or human induced pluripotent stem cells (hiPSCs) and established distinct RT patterns. An E-BAC harboring an early replicating chromosomal region replicated early during S phase, while E-BACs derived from RT transition regions (TTRs) and late replicating regions replicated in mid to late S phase. Analysis of E-BAC interactions with cellular chromatin (4C-seq) revealed that the early replicating E-BAC interacted broadly throughout the genome and preferentially with the early replicating compartment of the nucleus. In contrast, mid- to late-replicating E-BACs interacted with more specific late replicating chromosomal segments, some of which were shared between different E-BACs. Together, we describe a versatile system in which to study the structure and function of chromosomal segments that are stably maintained separately from the influence of cellular chromosome context.
Sequential function approximation with noisy data

Abstract We present a sequential method for approximating an unknown function sequentially using random noisy samples. Unlike the traditional function approximation methods, the current method constructs the approximation using one sample at a time. This results in a simple numerical implementation using only vector operations and avoids the need to store the entire data set. The method is thus particularly suitable when data set is exceedingly large. Furthermore, we present a general theoretical framework to define and interpret the method. Both upper and lower bounds of the method are established for the expectation of the results. Numerical examples are provided to verify the theoretical findings.
DIRECT COMPUTER MODELING

Abstract A new type of modeling, called discrete modeling, is developed. The approach is consistent with and requires the power provided by digital computers. Instead of utilizing a continuum approach, the models incorporate local molecular and long range type forces into n-body simulations. Extensive computer examples are described and discussed.
Evidence for isoenzymes of 4-hydroxycinnamic acid: CoA ligase in maize mesocotyls and their response to infection by Helminthosporium maydis race O☆

Abstract A comparison was made of patterns of 4-hydroxycinnamic acid: CoA ligase (CoA ligase, E.C.6.2.1.12) activities in near isogenic maize cultivars with differential resistance (B73Ht rkm) and susceptibility (B73Ht) to Helminthosporium maydis. CoA ligase activity was assayed with p-coumaric, caffeic and ferulic acids as substrates in fractions collected after molecular sieve column chromatography of protein extracts from maize mesocotyls. All CoA ligase activity eluted between a molecular size range of 42–77 kilodaltons. The CoA ligase elution profiles distinguished multiple peaks of activity and were different in uninoculated susceptible and resistant cultivars. Inoculation with H. maydis changed the elution profiles of the enzyme activities from the respective cultivars. The multiple peaks of enzyme activity in the elution profiles and their shift in response to infection indicate CoA ligase isoenzyme responses in these host-parasite interactions.
Presynaptic inhibition of primary nociceptive signals to dorsal horn lamina I neurons by dopamine

The dorsal horn of the spinal cord represents the first relay station in the pain pathway where primary nociceptive inputs are modulated by local circuits and by descending signals before being relayed to supraspinal nuclei. To determine whether dopamine can modulate primary nociceptive Aδ- and C-fiber signals, the effects of dopamine were tested on the excitatory postsynaptic currents (EPSCs) recorded from large lamina I neurons and from retrograde-labeled spinoparabrachial lamina I neurons upon stimulation of the L4/L5 dorsal root in horizontal spinal cord slices in vitro . Dopamine inhibited the EPSCs in a dose-dependent manner, with substantial inhibition (33%) at 1 μm and maximum inhibition (∼70%) at 10–20 μm. Dopamine reduced the frequency of miniature EPSCs recorded from large lamina I neurons, increased the paired pulse depression ratio of paired EPSCs, and induced similar inhibition of EPSCs after dialysis of large lamina I neurons with GDP-β-S, consistent with actions at presynaptic sites. Pharmacological experiments suggested that the inhibitory effects of dopamine were largely mediated by D4 receptors (53%). Similar inhibition (66%) by dopamine was observed on EPSCs recorded from ipsilateral large lamina I neurons 6 d after injection of complete Freund9s adjuvant in the hindpaw, suggesting that dopamine downregulates primary nociceptive inputs to lamina I neurons during chronic inflammatory pain. We propose that presynaptic inhibition of primary nociceptive inputs to lamina I projection neurons is a mechanism whereby dopamine can inhibit incoming noxious stimuli to the dorsal horn of the spinal cord. SIGNIFICANCE STATEMENT Lamina I projection neurons represent the main output for the pain signals from the dorsal horn of the spinal cord to brainstem and thalamic nuclei. We found that dopamine inhibits the nociceptive Aδ- and C-fiber synaptic inputs to lamina I projection neurons via presynaptic actions. Similar inhibitory effects of dopamine on the EPSCs were observed in rats subjected to complete Freund9s adjuvant to induce peripheral inflammation, suggesting that dopamine inhibits the synaptic inputs to lamina I neurons in the setting of injury. A better understanding of how primary nociceptive inputs to the dorsal horn of the spinal cord are modulated by descending monoaminergic signals may help in the development of new pharmacological strategies to selectively downregulate the output from lamina I projection neurons.
Cytochrome P450-Catalyzed Hydroxylation Initiating Ether Formation in Platensimycin Biosynthesis

Platensimycin (PTM) and platencin (PTN) are potent and selective inhibitors of bacterial and mammalian fatty acid synthases. The regio- and stereospecificity of the ether oxygen atom in PTM, which PTN does not have, strongly contribute to the selectivity and potency of PTM. We previously reported the biosynthetic origin of the 11 S,16 S-ether moiety by characterizing the diterpene synthase PtmT3 as a (16 R)- ent-kauran-16-ol synthase and isolating 11-deoxy-16 R-hydroxylated congeners of PTM from the Δ ptmO5 mutant. PtmO5, a cytochrome P450, was proposed to catalyze formation of the ether moiety in PTM. Here we report the in vitro characterization of PtmO5, revealing that PtmO5 stereoselectively hydroxylates the C-11 position of the ent-kaurane scaffold resulting in an 11 S,16 R-diol intermediate. The ether moiety, the oxygen of which originates from the P450-catalyzed hydroxylation at C-11, is formed via cyclization of the diol intermediate. This study provides mechanistic insight into ether formation in natural product biosynthetic pathways.
Approaching protein design with multisite λ dynamics: Accurate and scalable mutational folding free energies in T4 lysozyme

The estimation of changes in free energy upon mutation is central to the problem of protein design. Modern protein design methods have had remarkable success over a wide range of design targets, but are reaching their limits in ligand binding and enzyme design due to insufficient accuracy in mutational free energies. Alchemical free energy calculations have the potential to supplement modern design methods through more accurate molecular dynamics based prediction of free energy changes, but suffer from high computational cost. Multisite λ dynamics (MSλD) is a particularly efficient and scalable free energy method with potential to explore combinatorially large sequence spaces inaccessible with other free energy methods. This work aims to quantify the accuracy of MSλD and demonstrate its scalability. We apply MSλD to the classic problem of calculating folding free energies in T4 lysozyme, a system with a wealth of experimental measurements. Single site mutants considering 32 mutations show remarkable agreement with experiment with a Pearson correlation of 0.914 and mean unsigned error of 1.19 kcal/mol. Multisite mutants in systems with up to five concurrent mutations spanning 240 different sequences show comparable agreement with experiment. These results demonstrate the promise of MSλD in exploring large sequence spaces for protein design.
Point of care ultrasound is associated with decreased ED length of stay for symptomatic early pregnancy

Abstract Introduction Emergency physicians (EP) can accurately rule out ectopic pregnancy with pelvic point of care ultrasound (PPOCUS). Multiple studies have suggested that PPOCUS may decrease length of stay (LOS) for emergency department (ED) patients presenting with early symptomatic pregnancy compared to comprehensive ultrasound (CUS). This systematic review and meta-analysis examines the association between the use of PPOCUS vs CUS and ED LOS. Methods A systematic review of the literature was performed. Patients with symptomatic early pregnancy receiving EP-performed PPOCUS were compared to patients receiving CUS without PPOCUS. Keywords and search terms were generated for PPOCUS, ED LOS and CUS. Two independent reviewers screened abstracts for inclusion. A third reviewer was used when conflicts arose to gain consensus. Formal bias assessment was performed on included studies. Meta-analysis was carried out, pooling the mean differences between studies using a random-effects model. Results 2980 initial articles were screened, 32 articles underwent detailed review, 8 underwent bias assessment, and 6 were included in the final meta-analysis. There were 836 patients in the study group and 1514 in the control group. All studies showed a decreased LOS in the PPOCUS group with a mean decrease of 73.8 min (95% CI 49.1, 98.6). Two studies not included in the meta-analysis also showed significantly decreased LOS with PPOCUS. Conclusion Use of PPOCUS in the evaluation of patients with symptomatic early pregnancy is associated with decreased LOS in patients ultimately diagnosed with intrauterine pregnancy. This review suggests that this finding is generalizable to a variety of practice settings.
Synchrony in fall leaf drop: chlorophyll degradation, color change, and abscission layer formation in three temperate deciduous tree species.

Premise of the study Deciduous tree species remove some nutrients from their leaves during fall leaf senescence through retranslocation. Retranslocation impacts the timeline of leaf fall, amount of active chlorophyll, and overall leaf nitrogen content as fall color change occurs. Our objective was to identify interspecific differences in the timing of abscission layer formation, leaf color change, and the level of chlorophyll degradation of young trees during fall senescence. Methods Leaf relative chlorophyll content for three tree species was measured during fall 2015 by a greenness meter. These measurements were calibrated for each species through spectrophotometric determination of leaf chlorophyll concentration. Abscission layer formation was tracked using light microscopy of sampled leaves. Excised leaves were photographed on a flat white surface to track species leaf color through time. Key results All three species had different chlorophyll declination rates throughout the fall season. The maple species started with less chlorophyll and began abscission layer formation earlier. The other two species had a similar starting chlorophyll level and onset timing of abscission layer formation. Visible leaf color change was not associated with a threshold in either chlorophyll degradation or abscission layer formation across species. Conclusions Maple species degraded less chlorophyll on average, in the fall, than did the oak and beech species. The rate of chlorophyll degradation in coordination with abscission layer formation varied by species. Color change was not a good predictor of level of chlorophyll degradation in leaves across species.
Stochastic Optimal Control of Random Evolutions and SES

We consider stochastic optimal control (SOC) of controlled Markov [150] and semi-Markov Random Evolutions [154] Also, we study SOC for controlled averaged, merged and diffusion Random Evolutions (RE) [154] We introduce the cost functional for these REs, and derive the Hamilton-Jacobi-Bellman (HJB)-equations These results we apply to the stochastic evolutionary systems, such as traffic, storage and diffusion processes in Markov and semi-Markov random media We note that the all equalities and inequalities in the following first six sections are understood in weak sense.
Effects of violent crime and vehicular crashes on active mode choice decisions in New York City

Abstract Substantial research has explored the effects of different variables on mode choice with the intent of understanding this behavior so that active modes can be encouraged. This study furthers that effort by investigating the impact of perceived danger from crime on the probability of choosing an active mode of transportation among travellers in New York City from 2009 to 2011. This study uses trip data from the New York Metropolitan Transportation Council Regional Household Travel Survey along with historical crime and vehicle collision data to estimate a random utility model. Traveller demographic information, travel cost and incidence of crime and vehicle collisions involving pedestrians or cyclists are used as explanatory variables in a mixed logit model. The finding implies that travellers could be encouraged to cycle by reducing crime levels, or by being provided an alternative route with less crime. Based on the model results it can be determined that travellers are willing to pay $0.66 for a 1000-point reduction in crime severity. An increase in crime of 1% has a much greater impact on bike ridership (2.11% reduction) than on walking (0.06% reduction). Removing crime completely would improve a traveler’s trip satisfaction by as much as $0.26 per trip. Compared to crime, collision rate has a much stronger impact on bike ridership, with an elasticity of −7.56 (3.6 times higher elasticity than crime).
Bayesian Learning for Classification using a Uniform Dirichlet Prior

In Bayesian learning, designs based on noninformative priors are appropriate when the user cannot confidently identify the data-generating distribution. While such learners cannot achieve the performance of those based on a well-matched subjective prior, they impart a robustness against poor prior selection. The uniform Dirichlet distribution is the true non-informative prior as it has full support over the space of candidate distributions; additionally, it leads to closed-form posteriors. This work applies such a prior to classification using the 0–1 loss, determines the optimal Bayes classifier and the corresponding minimum probability of error, and analyzes the results.
Abstract 254: Predictors of Immune Checkpoint Inhibitor Associated Cardiotoxicity

Background: Immune checkpoint inhibitors (ICIs), including programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1) and cytotoxic lymphocyte antigen-4 (CTLA-4) inhibitors, are increas...
Rural-Urban Differences in Dental Service Utilization and Dental Service Procedures Received Among US Adults: Results From the 2016 Medical Expenditure Panel Survey.

PURPOSE To assess rural-urban differences in dental service use and procedures and to explore the interaction effects of individual- and county-level factors on having dental service use and procedures. METHODS Data were from the 2016 Medical Expenditure Panel Survey (MEPS). We assessed rural-urban differences in 3 outcome variables: number of dental visits (1, 2, or 3+ visits), preventive care procedures (Yes/No), and treatment procedures (Yes/No). The study sample included 8,199 adults ≥ 18 years of age who reported at least 1 dental visit in the past year. Sampling weights embedded in MEPS were incorporated into all the analyses. FINDINGS A significant interaction between residential location and race/ethnicity (P = .030) suggested limited access to dental visits for minority groups, especially for blacks in the more rural areas. Adults from a more rural area were less likely to have received a preventive procedure (AOR = 0.55, 95% CI: 0.35-0.87) than those from an urban area. Adults of racial/ethnic minority groups, with lower SES, and without dental insurance were less likely to have received a preventive procedure (all P < .01) but were more likely to have received a treatment procedure (all P < .05). CONCLUSIONS The study showed rural adults were less likely to have received preventive dental procedures than their urban counterparts. Racial/ethnic minority groups living in a more rural area had even more limited access to dental services. Innovative service delivery models that integrate telehealth and community-based case management may contribute to addressing these gaps in rural communities.
Measurement report: Sulfuric acid nucleation and experimental conditions in a photolytic flow reactor

Abstract. Nucleation rates involving sulfuric acid and water measured in a photolytic flow reactor have decreased considerably over a time period of several years. Results show that the system – flow reactor, gas supplies and lines, flow meters, valves, H 2 SO 4 photo-oxidant sources – has reached a baseline stability that yields nucleation information such as cluster free energies. The baseline nucleation rate is punctuated by temporary bursts that in many instances are linked to cylinder changes, delineating this source of potential contaminants. Diagnostics were performed to better understand the system, including growth studies to assess H 2 SO 4 levels, chemiluminescent NO and NO x detection to assess the HONO source, and deployment of a second particle detector to assess the nanoparticle detection system. The growth of seed particles shows trends consistent with the sizes of nucleated particles and provides an anchor for calculated H 2 SO 4 concentrations. The chemiluminescent detector revealed that small amounts of NO are present in the HONO source, ∼ 10 % of HONO. The second condensation-type particle counter indicates that the nanoparticle mobility sizing system has a bias at low sulfuric acid levels. The measured and modeled nucleation rates represent upper limits to nucleation in the binary homogeneous system, H 2 SO 4 -H 2 O, as contaminants might act to enhance nucleation rates and ion-mediated nucleation may contribute. Nonetheless, the experimental nucleation rates, which have decreased by an order of magnitude or larger since our first publication, extrapolate to some of the lowest rates reported in experiments with photolytic H 2 SO 4 . Results from experiments with varying water content and with ammonia addition are also presented and have also decreased by an order of magnitude from our previous work; revised energetics of clusters in this three-component system are derived which differ from our previous energetics mainly in the five-acid and larger clusters.
Traffic Rate Network Tomography with Higher-Order Cumulants.

Network tomography aims at estimating source-destination traffic rates from link traffic measurements. This inverse problem was formulated by Vardi in 1996 for Poisson traffic over networks operating under deterministic as well as random routing regimes. In this paper we expand Vardi's second-order moment matching rate estimation approach to higher-order cumulant matching with the goal of increasing the column rank of the mapping and consequently improving the rate estimation accuracy. We develop a systematic set of linear cumulant matching equations and express them compactly in terms of the Khatri-Rao product. Both least squares estimation and iterative minimum I-divergence estimation are considered. We develop an upper bound on the mean squared error (MSE) in least squares rate estimation from empirical cumulants. We demonstrate for the NSFnet that supplementing Vardi's approach with third-order empirical cumulant reduces its averaged normalized MSE relative to the theoretical minimum of the second-order moment matching approach by about 12%-18%. This minimum MSE is obtained when Vardi's second-order moment matching approach is based on the theoretical rather than the empirical moments.
COVID-19 pandemic impact on experiences and perceptions of nurse graduates

Abstract Background Transitioning from education to practice is stressful for new nurses and those entering new roles and can lead to workforce attrition and burnout. This dynamic is likely complicated when graduates are transitioning to practice during a pandemic. Purpose The purpose of this study was to describe recent nurse graduates' perceptions of the impact of the COVID-19 pandemic on their transition from education to practice. Methods We conducted an online survey of BSN, RN-BSN, and DNP students who graduated between December 2019 and April 2020 (n = 82), including demographics, employment information, and free-response questions about the impact of the pandemic on their transition experiences, post-graduation plans, and perceptions of nursing. We used a qualitative descriptive approach to content analysis to synthesize and summarize the data. Results Participants expressed three overarching concerns: 1) altered plans such as difficulty finding employment; 2) logistical, system-related stressors including licensing delays and chaotic onboarding; and 3) feeling pride in profession despite perceiving ambivalence in public discourse. Conclusion COVID-19 exacerbated challenges often experienced by new graduates. Common stressors, intensified during the pandemic, could exert long-term effects on the workforce. Educators and healthcare organizations must work to ensure nursing graduates receive the necessary support for a successful transition.
Time Window of Head Impact Kinematics Measurement for Calculation of Brain Strain and Strain Rate in American Football

Wearable devices have been shown to effectively measure the head’s movement during impacts in sports like American football. When a head impact occurs, the device is triggered to collect and save the kinematic measurements during a predefined time window. Then, based on the collected kinematics, finite element (FE) head models can calculate brain strain and strain rate, which are used to evaluate the risk of mild traumatic brain injury. To find a time window that can provide a sufficient duration of kinematics for FE analysis, we investigated 118 on-field video-confirmed football head impacts collected by the Stanford Instrumented Mouthguard. The simulation results based on the kinematics truncated to a shorter time window were compared with the original to determine the minimum time window needed for football. Because the individual differences in brain geometry influence these calculations, we included six representative brain geometries and found that larger brains need a longer time window of kinematics for accurate calculation. Among the different sizes of brains, a pre-trigger time of 40 ms and a post-trigger time of 70 ms were found to yield calculations of brain strain and strain rate that were not significantly different from calculations using the original 200 ms time window recorded by the mouthguard. Therefore, approximately 110 ms is recommended for complete modeling of impacts for football.
Mechanisms revisited

This paper defends an interventionist treatment of mechanisms and contrasts this with Waskan (forthcoming). Interventionism embodies a difference-making conception of causation. I contrast such conceptions with geometrical/mechanical or “actualist” conceptions, associating Waskan’s proposals with the latter. It is argued that geometrical/mechanical conceptions of causation cannot replace difference-making conceptions in characterizing the behavior of mechanisms, but that some of the intuitions behind the geometrical/mechanical approach can be captured by thinking in terms of spatio-temporally organized difference-making information.
Student Uptake in Electronic Discussions: Examining Online Discourse in Literacy Preservice Classrooms

AbstractRecent research has provided evidence of the potential benefits of using both synchronous and asynchronous online conversations in face-to-face, mixed-mode, and online classes. However, research has also suggested that these benefits are not inherent just by adopting online discussions into classroom work. In this paper, we draw from a larger literature review to discuss both the positive and negative aspects of electronic conversations. We then present research that showcases the possibilities of online conversations in teacher education methodology classrooms. We conclude with a second research study that addresses the notion of student uptake, highlighting implications for teacher educators who want to successfully implement discussion forums in their curricula.
Option Implied Volatilities and Corporate Bond Yields: A Dynamic Factor Approach

This paper estimates dynamic factors from the term structure of credit spreads and the term structure of equity option implied volatilities, and it provides a comprehensive characterization of the dynamic relationships among those credit spread factors and equity volatility factors. The paper finds strong evidence that the volatility factors, especially the volatility level factor, Granger cause credit spread levels, confirming the theoretical predictions of Merton (1974) in a significantly richer and more nuanced environment than previously achieved. Simultaneously, the paper also finds evidence of reverse Granger causality from credit spreads to equity volatility, operating through the slope factors, consistent with the market microstructure literature, which finds that price discovery often happens first in bond markets. Hence the results extend both the corporate bond pricing literatures, deepening our understanding of stock and bond market interaction and suggesting profitable trading strategies.
Chapter 24 Quantification, localization, and tissue specificities of mouse mitochondrial reactive oxygen species production.

Abstract Mitochondria play a critical role in many different pathologic conditions. Increasing evidence has shown that mitochondrial reactive oxygen species (ROS) production may provide an etiologic link between mitochondria and pathologics. The widespread use of laboratory mice as models for a host of human diseases makes the quantification and localization of ROS production from mice an important endeavor. This chapter presents approaches to the quantification and localization of ROS from mouse brain, liver, and beta cell mitochondria. Techniques for the isolation of mitochondria and mitochondrial fractions and the subsequent quantification of ROS with Amplex Red or a FACS‐based method on intact cells are described.