cssi/SciSciGPT-SciSciNet huggingface dataset:
Tutorial on Causal Inference and Counterfactual Reasoning

As computing systems are more frequently and more actively intervening to improve people’s work and daily lives, it is critical to correctly predict and understand the causal effects of these interventions. Conventional machine learning methods, built on pattern recognition and correlational analyses, are insufficient for causal analysis. This tutorial will introduce participants to concepts in causal inference and counterfactual reasoning, drawing from a broad literature on the topic from statistics, social sciences and machine learning. We first motivate the use of causal inference through examples in domains such as recommender systems, social media datasets, health, education and governance. To tackle such questions, we will introduce the key ingredient that causal analysis depends on—counterfactual reasoning—and describe the two most popular frameworks based on Bayesian graphical models and potential outcomes. Based on this, we will cover a range of methods suitable for doing causal inference with large-scale online data, including randomized experiments, observational methods like matching and stratification, and natural experiment-based methods such as instrumental variables and regression discontinuity. We will also focus on best practices for evaluation and validation of causal inference techniques, drawing from our own experiences. We show application of these techniques through Jupyter notebooks, demonstrating how core concepts translate to empirical work. Throughout, we emphasise considerations of working with large-scale data from online systems, such as logs of user interactions or social data. The goal of this tutorial is to help you understand the basics of causal inference, be able to appropriately apply the most common causal inference methods, and be able to recognize situations where more complex methods are required. Sections Introduction: Patterns and predictions are not enough Methods: Conditioning-based methods and natural experiments Considerations: Special considerations with large-scale and network data Broader Landscape: Heterogeneous treatment effects, machine learning and causal discovery References: Further reading
Frequency Following Response and Speech Recognition Benefit for Combining a Cochlear Implant and Contralateral Hearing Aid.

Multiple studies have shown significant speech recognition benefit when acoustic hearing is combined with a cochlear implant (CI) for a bimodal hearing configuration. However, this benefit varies g...
Black Women Graduate Students on Whiteness and Barrier Breaking in Leadership

The “multiple jeopardies” that often act as barriers for Black women in both leadership and society may be the same barriers that provide the uniquely diversified leadership perspectives needed to address a rapidly changing global society. However, the dominant image of leadership is still primarily White and male. Disrupting this image calls for the centering of little-known lived experiences and insights from those on the margins of the leadership narrative, such as the 15 Black women graduate student participants included in this phenomenological study. Findings from this study highlight the hidden and invisible obstacles facing Black women, as well as how these obstacles impact: (a) perceptions of their leadership qualities, (b) personal leadership philosophies, and (c) potential employers.
Quantifying Methane Emissions from Natural Gas Water Heaters

Methane emissions from natural gas appliances remain the least characterized portion of the fossil-fuel supply chain. Here we examine water heaters from 64 northern California homes to (1) quantify methane emissions from natural gas leaks and incomplete combustion while off, turning on or off, and in steady-state operation from 35 homes; and (2) characterize daily usage patterns over ∼1-2 months per water heater to estimate activity factors from 46 homes. Individual tankless water heaters emitted 2390 [95% CI: 2250, 2540] g CH4 yr-1 on average, 0.93% [0.87%, 0.99%] of their natural gas consumed, primarily from on/off pulses. Storage water heaters emitted 1400 [1240, 1560] g CH4 yr-1 on average, 0.39% [0.34%, 0.43%] of their natural gas consumption. Despite higher methane emissions, tankless water heaters generate 29% less CO2e20 than storage water heaters because they use less energy to heat a unit of water. Scaling our measured emissions by the number of storage and tankless water heaters in the United States (56.8 and 1.2 million, respectively), water heaters overall emitted an estimated 82.3 [73.2, 91.5] Gg CH4 yr-1, 0.40% [0.35%, 0.44%] of all natural gas consumed by these appliances, comparable in percentage to the EPA's estimate of methane emissions from upstream natural gas production.
Retrieval-Based Learning: Active Retrieval Promotes Meaningful Learning

Retrieval is the key process for understanding learning and for promoting learning, yet retrieval is not often granted the central role it deserves. Learning is typically identified with the encoding or construction of knowledge, and retrieval is considered merely the assessment of learning that occurred in a prior experience. The retrieval-based learning perspective outlined here is grounded in the fact that all expressions of knowledge involve retrieval and depend on the retrieval cues available in a given context. Further, every time a person retrieves knowledge, that knowledge is changed, because retrieving knowledge improves one’s ability to retrieve it again in the future. Practicing retrieval does not merely produce rote, transient learning; it produces meaningful, long-term learning. Yet retrieval practice is a tool many students lack metacognitive awareness of and do not use as often as they should. Active retrieval is an effective but undervalued strategy for promoting meaningful learning.
A conservative approach to scaling magneto-inertial fusion concepts to larger pulsed-power drivers

The Magnetized Liner Inertial Fusion (MagLIF) experimental platform [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] represents the most successful demonstration of magneto-inertial fusion (MIF) techniques to date in pursuit of ignition and significant fusion yields. The pressing question remains regarding how to scale MIF concepts like MagLIF to more powerful pulsed-power drivers while avoiding significant changes in physical regimes that could adversely impact performance. In this work, we propose a conservative approach for scaling general MIF implosions, including MagLIF. Underpinning our scaling approach is a theoretical framework describing the evolution of the trajectory and thickness of a thin-walled, cylindrical, current-driven shell imploding on preheated, adiabatic fuel. By imposing that scaled implosions remain self-similar, we obtain a set of scaling rules expressing key target design parameters and performance metrics as functions of the maximum driver current I max. We identify several scaling paths offering unique, complementary benefits and trade-offs in terms of physics risks and driver requirements. Remarkably, when scaling present-day experiments to higher coupled energies, these paths are predicted to preserve or reduce the majority of known performance-degrading effects, including hydrodynamic instabilities, impurity mix, fuel energy losses, and laser-plasma interactions, with notable exceptions clearly delineated. In the absence of α heating, our scaling paths exhibit neutron yield per-unit-length scaling as Y ∝ [ I max 3 , I max 4.14 ] and ignition parameter scaling as χ ∝ [ I max , I max 2.14 ]. By considering the specific physics risks unique to each scaling path, we provide a roadmap for future investigations to evaluate different scaling options through detailed numerical studies and scaling-focused experiments on present-day facilities. Overall, these results highlight the potential of MIF as a key component of the national ignition effort.
Prospective evaluation of airway management in pediatric out-of-hospital cardiac arrest

Abstract Objective The objective of the study was to identify the association between airway management modality and time to the initial dose of epinephrine in pediatric out-of-hospital cardiac arrest (OHCA). Methods This was a prospective observational study conducted between April 2016 to April 2018. Ten Emergency Medical Services (EMS) agencies in 2 US metropolitan areas, which were part of the Resuscitation Outcomes Consortium research network, participated in the study. We included all EMS-treated OHCA patients less than 18 years of age during the study period. Study outcomes included time to the initial dose of epinephrine, airway management success rates, rescue techniques, and complications (e.g. pneumothorax, pneumonia). Results The study included a total of 155 patients, 67% were male, and 55% were less than age one. The airway management modality (TI, SGA, BMV) was not associated with the time to the intial dose of epinephrine in the adjusted analysis. Tracheal intubation (TI) was the most common airway management modality (47.1%) followed by bag-mask-ventilation (BMV) (40.7%), and supraglottic airways (SGA) (12.3%). Success was 65.7% for TI and 94.7% for SGA. We found a significant difference in the proportion of initial survivors diagnosed with pneumonia on chest X-ray between those with BMV (1/19) versus TI (13/21) p Conclusions In this prospective study, the airway management modality was not associated with the time to the initial dose of epinephrine. Unexpectedly, pneumonia was significantly more common among children treated with TI compared to BMV. SGAs had high first-attempt success rates, while intubation success rates were low.
Incisional hernia formation can be reduced following hyperthermic intraperitoneal chemotherapy with increased suture length to wound length ratio fascial closure

INTRODUCTION: Incisional hernia (IH) is a common postsurgical complication of laparotomy. The impact of hyperthermic intraperitoneal chemotherapy on fascial healing has not been evaluated. The aim of this study is to determine whether utilizing a 4:1 suture length to wound length ratio (SL:WL) during fascial closure reduces the risk of IH following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CS-HIPEC). METHODS: A retrospective review of patients who underwent HIPEC between 2013 and 2019 at a single institution was performed. Demographics and IH rates were compared between patients closed with a 4:1 SL:WL and patients with standard fascial closure (SFC). Hernias were detected on physical examination or on cross-sectional imaging studies. RESULTS: Eighty-six patients who underwent HIPEC were included in the study. A 4:1 SL:WL was utilized in 26.7% (n = 23) of HIPEC cases and the remaining 73.3% (n = 63) of patients received SFC methods. Three patients in the 4:1 SL:WL group developed hernias, whereas 22 patients in the SFC group had hernias (13.0% vs. 34.9%, P = 0.048). The incidence of IHs was similar across the body mass index, smoking status, and operative time categories. CONCLUSION: Utilizing a 4:1 SL:WL during fascial closure may reduce the rates of IH in the HIPEC population, but larger sample sizes and longer follow-up are required to determine the statistical significance of this intervention.
Emerging microdroplet chemistry for synthesis and analysis

Abstract Recent studies have shown that remarkable reaction acceleration can be achieved at the air/solution interface of microdroplets. The unique environment of microdroplets can drive reactions that are thermodynamically unfavorable in bulk. These features allow microdroplet chemistry to impact many fields including chemical derivatization, reaction mechanistic studies, high-throughput reaction screening, and rapid small-scale, green and sustainable synthesis. This minireview describes the unique reactivities in microdroplets and acceleration mechanisms with examples of experimental and theoretical studies. Various methods for scale-up of microdroplet reactions and the accelerated derivatization for in-situ molecular analysis are also discussed.
Impact of Early Introduction to the Neurosciences on West Virginia High School Students via the Brain Bee.

The science, technology, engineering, and math (STEM) fields are often underrepresented due to lack of interest or exposure. The Brain Bee is a neuroscience competition for high school students meant to inspire future leaders in the neurosciences. A regional Brain Bee competition hosted in West Virginia was led by medical students and neurology residents with the goal of increasing high school student interest in the neurosciences. The West Virginia Brain Bee competition consisted of a neuroanatomy practical, a written exam, and a clinical assessment. Other fun neuroscience educational activities were also offered to students throughout the competition day. Students were surveyed before and after the competition day. Student interest in pursuing a neuroscience career increased (3.24 to 3.58, p = 0.043), and confidence in neuroscience knowledge increased (2.88 to 3.12, p = 0.036). Qualitative assessment revealed the importance of role models and a supportive environment for student learning. The West Virginia Brain Bee increased high school student interest in and confidence of neuroscience knowledge. This competition may be a meaningful way to connect high school students with potential mentors in the neurosciences and may also help foster an interest in pursuing a career in the neurosciences in the future.
Chernozem: Soil of the Steppe

Chernozem is the predominant soil of Moldova and the country’s greatest natural treasure. Its profile is very thick, well humified and well structured – properties inherited from the steppe. Only grassland with its many-branched and deeply-ramified root system is able to produce abundant organic matter and humification throughout the solum. The underlying horizon, enriched in secondary carbonates, is a marker of the soil water regime that determines the different subtypes of chernozem. From north to south, less and less water percolates through the profile; in phase with the water regime, Leached chernozem gives way to Typical chernozem which, in turn, gives way to Carbonate chernozem. All chernozem share the thick, black, granular topsoil – remarkable for its fertility and resilience – but more than a century of cropping has degraded the chernozem; even where the soil profile is intact, it has lost half of its native humus and requires different and better treatment if its productivity is to be sustainable.
Red Clover Breeding and Genetics

Publisher Summary Red clover, Trifolium pratense L., has been a significant forage legume among agricultural crops. Red clover is adapted to a wide range of soil types, pH levels, and environmental conditions. This plasticity has enabled red clover to retain its usefulness for hay, silage, pasture, and soil improvement in much of the temperate region of the world. Red clover is a nitrogen-fixing legume, thus contributing to the supply of nitrogen available in the soil for subsequent crops. Red clover is a self-incompatible cross-pollinated species that, under natural conditions, produces very few self-seed. The mechanism of self-incompatibility is the one-locus, gametophytic S-allele system in which plants with the same S-alleles are prevented from selfing by slow growth of pollen tubes through styles. The system also prevents cross-fertilization of plants that have the same S-allele genotype. Details of the S-allele systems in red clover have been investigated by inbreeding via pseudo-self-compatibility (PSC).
Testing Hypotheses on Simulated Data: Why Traditional Hypotheses-Testing Statistics are Not Always Adequate for Simulated Data, and How to Modify Them

To check whether a new algorithm is better, researchers use traditional statistical techniques for hypotheses testing. In particular, when the results are inconclusive, they run more and more simulations (n2 > n1, n3 > n2, . . . , nm > nm−1) until the results become conclusive. In this paper, we point out that these results may be misleading. Indeed, in the traditional approach, we select a statistic and then choose a threshold for which the probability of this statistic “accidentally” exceeding this threshold is smaller than, say, 1%. It is very easy to run additional simulations with ever-larger n. The probability of error is still 1% for each ni, but the probability that we reach an erroneous conclusion for at least one of the values ni increases as m increases. In this paper, we design new statistical techniques oriented towards experiments on simulated data, techniques that would guarantee that the error stays under, say, 1% no matter how many experiments we run. I. HYPOTHESES TESTING: AN IMPORTANT APPLIED PROBLEM One of the main uses of statistics is to compare two (or more) hypotheses. For example, we would like to check whether a new medical treatment is better than the previously known one. Let us describe this problem in more precise terms. Usually, an efficiency of a method can be described by an appropriate numerical quantity x. For example, an efficiency of an anti-cholesterol medicine can be described by the average amount to which its use lowers the patient’s originally high cholesterol level during a certain period of time. So, we arrive at the following problem: • we know the average amount μ corresponding to the original hypothesis (e.g., the original treatment); • we have the results x1, . . . , xn of the experiments with the new method. Based on these results, we would like to check whether the new method is indeed better, i.e., whether for the new method, the mean value μx is larger than μ. II. HYPOTHESES TESTING: HOW IT IS CURRENTLY DONE There are many known statistical methods for hypotheses testing; see, e.g., [5], [6]. One of these methods is as follows: we compute the population average x = x1 + . . . + xn n and the population standard deviation s = √√√√ 1 n− 1 · n ∑
Constitutional Pluralism and Democratic Politics: Reflections on the Interpretive Approach of Baker V. Carr

Baker v. Carr is one of the Supreme Court's most important opinions, not least because its advent signaled the constitutionalization of democracy. Unfortunately, as is typical of the Court's numerous forays into democratic politics, the decision is not accompanied by an apparent vision of the relationship among democratic practice, constitutional law, and democratic theory. In this Article, I revisit Baker and provide several democratic principles that I argue justifies the Court's decision to engage the democratic process. I examine the decision from the perspective of one of its chief contemporary critics, Justice Frankfurter. I sketch an approach, described as constitutional pluralism, for thinking about Baker and other cases involving judicial supervision of democratic politics. Using constitutional pluralism as an interpretive tool, I argue that the aim of judicial involvement in democratic politics ought to be to vindicate specific democratic principles. I describe the conditions under which the federal courts should respect the judgment of democratic actors.
Handeln statt Warten: Ein mehrstufiger Ansatz zur Bewältigung des Klimaproblems

Die Klimaproblematik ist sehr komplex und auf der internationalen politischen Agenda immer noch relativ neu. Daher ist es nicht sinnvoll, auf den Abschluss eines globalen Abkommens zu warten. Es ware besser, einen mehrstufigen Losungsansatz zu verfolgen, der auf der lokalen Ebene ansetzt, Vorteile klimapolitischer Anstrengungen auf mehreren Ebenen maximiert, und ein Prozess des Experimentierens und Lernens uber Klimapolitik initiiert. Die konventionelle Theorie kollektiven Handelns sagt uns, dass die effiziente Nutzung von Ressourcen nur durch zwei Masnahmen moglich ist: Privatisierung oder Verstaatlichung. Diese Ansicht behindert Fortschritte. Um dem Klimawandel langfristig erfolgreich zu begegnen, mussen sich alltagliche Verhaltensmuster von Einzelpersonen, Familien, Firmen, Gemeinden und Regierungen auf verschiedenen Ebenen andern – insbesondere in den entwickelten Landern.
Comparing Two Sample Means

Up to now we have concentrated on single batches of numbers and on using single batches of numbers as samples for purposes of making inferences about the populations from which they were selected. The principles discussed in Chapters 7–11, however, can also be applied to the task of comparing batches, which we began to explore in Chapter 4. Figure 12.1 compares two batches of numbers. These batches are the areas (in square meters) of house floors for two periods (Formative and Classic). After careful consideration of possible sources of bias we decide to work with these two batches as if they were random samples, taking each as a sample of house floors for its period. The sample for the Formative period consists of 32 house floors, and the sample for the Classic period consists of 52 house floors. We begin to explore the two samples with a back-to-back stem-and-leaf plot at the left in Fig. 12.1. This plot reveals that both samples are single peaked and symmetrical enough that the mean would be a useful index of their levels. Neither is a perfect single-peaked and symmetrical shape, but both are quite as single peaked and symmetrical as one has any right to expect in relatively small batches of numbers like this.
The hypercorrection effect persists over a week, but high-confidence errors return

People’s knowledge about the world often contains misconceptions that are well-learned and firmly believed. Although such misconceptions seem hard to correct, recent research has demonstrated that errors made with higher confidence are more likely to be corrected with feedback, a finding called the hypercorrection effect. We investigated whether this effect persists over a 1-week delay. Subjects answered general-knowledge questions about science, rated their confidence in each response, and received correct answer feedback. Half of the subjects reanswered the same questions immediately, while the other half reanswered them after a 1-week delay. The hypercorrection effect occurred on both the immediate and delayed final tests, but error correction decreased on the delayed test. When subjects failed to correct an error on the delayed test, they sometimes reproduced the same error from the initial test. Interestingly, high-confidence errors were more likely than low-confidence errors to be reproduced on the delayed test. These findings help to contextualize the hypercorrection effect within the broader memory literature by showing that high-confidence errors are more likely to be corrected, but they are also more likely to be reproduced if the correct answer is forgotten.
How the medical staff copes with dying patients: a critical review.

Although not conclusive, the literature reviewed suggests that as a result both of their personality structures and the training they receive, medical practitioners associate dying patients with fa...
Regulating the Regulators: The Conflict between the Congressional Oversight Subcommittee and the FCC

Between 1957 and 1960, a congressional subcommittee battled with the Federal Communications Committee (FCC) over the awarding of major market TV station licenses. Hearings were held after suspicions were raised in Congress that some license applicants had inappropriately contacted commissioners during award deliberations, and that some commissioners had accepted “favors” in exchange for sympathetic votes. The resulting volatile investigation cost two commissioners and a White House aide their jobs, but more importantly resulted in new regulations concerning ex parte communications and commissioner standards of ethical conduct. This article analyzes the tumultuous events that led to the creation of the new standards.
Discrimination of viable and non‐viable cells using propidium iodide in two color immunofluorescence

The relative ease with which a flow cytometer can perform simultaneous two color immunofluorescence to examine subpopulations of lymphoid cells has been well documented. Thus, flow cytometers equipped with only a single argon laser can be used to delineate various cell types by exciting both fluorescein- and phycoerythrin-conjugated antibodies to cell surface antigens. One problem that remains, however, is the artifactual staining of dead cells and clumps, which cannot be distinguished from viable cells on the basis of cell surface staining characteristics. We describe a method for simultaneous two color analysis or sorting of viable leukocytes which requires only a single laser. The method utilizes propidium iodide, which stains dead cells and thereby excludes such cells from the analysis. Using this method, as many as four viable cell types have been simultaneously analyzed in a single sample.
Integrated intravascular optical coherence tomography (OCT) - ultrasound (US) catheter for characterization of atherosclerotic plaques in vivo

A miniature integrated intravascular optical coherence tomography (OCT) - ultrasound (US) catheter for real-time imaging of atherosclerotic plaques has been developed, providing high resolution and deep tissue penetration at the same time. This catheter, with an outer diameter of 1.18mm, is suitable for imaging in human coronary arteries. The first in vivo 3D imaging of atherosclerotic microstructure in a rabbit abdominal aorta obtained by an integrated OCT-US catheter is presented. In addition, in vitro imaging of cadaver coronary arteries were conducted to demonstrate the imaging capabilities of this integrated catheter to classify different atherosclerotic plaque types.
The passive control of compressible boundary layer growth by boundary layer trips

The passive control of compressible boundary layer growth by boundary layer trips has been studied experimentally. Axisymmetric trips and three dimensional trips were used in this study. The nomial freestream Mach numbers are 1.5 and 4. The results show that trips are effective in promoting boundary layer growth. Trips are more effective for Mach 1.5 flows than for Mach 4 flows.
Cross talk between the nuclease and helicase activities of Dna2: role of an essential iron–sulfur cluster domain

Dna2 nuclease/helicase is a multitasking protein involved in DNA replication and recombinational repair, and it is important for preservation of genomic stability. Yeast Dna2 protein contains a conserved putative Fe–S (iron–sulfur) cluster signature motif spanning the nuclease active site. We show that this motif is indeed an Fe–S cluster domain. Mutation of cysteines involved in metal coordination greatly reduces not just the nuclease activity but also the ATPase activity of Dna2, suggesting that the nuclease and helicase activities are coupled. The affinity for DNA is not significantly reduced, but binding mode in the C to A mutants is altered. Remarkably, a point mutation (P504S), proximal to the Fe–S cluster domain, which renders cells temperature sensitive, closely mimics the global defects of the Fe–S cluster mutation itself. This points to an important role of this conserved proline residue in stabilizing the Fe–S cluster. The C to A mutants are deficient in DNA replication and repair in vivo, and, strikingly, the degree to which they are defective correlates directly with degree of loss of enzymatic activity. Taken together with previous results showing that mutations in the ATP domain affect nuclease function, our results provide a new mechanistic paradigm for coupling between nuclease and helicase modules fused in the same polypeptide.
WebTraceMiner: a web service for processing and mining EST sequence trace files

Expressed sequence tags (ESTs) remain a dominant approach for characterizing the protein-encoding portions of various genomes. Due to inherent deficiencies, they also present serious challenges for data quality control. Before GenBank submission, EST sequences are typically screened and trimmed of vector and adapter/linker sequences, as well as polyA/T tails. Removal of these sequences presents an obstacle for data validation of errorprone ESTs and impedes data mining of certain functional motifs, whose detection relies on accurate annotation of positional information for polyA tails added posttranscriptionally. As raw DNA sequence information is made increasingly available from public repositories, such as NCBI Trace Archive, new tools will be necessary to reanalyze and mine this data for new information. WebTraceMiner (www.conifergdb.org/software/ wtm) was designed as a public sequence processing service for raw EST traces, with a focus on detection and mining of sequence features that help characterize 3 0 and 5 0 termini of cDNA inserts, including vector fragments, adapter/linker sequences, insert-flanking restriction endonuclease recognition sites and polyA or polyT tails. WebTraceMiner complements other public EST resources and should prove to be a unique tool to facilitate data validation and mining of error-prone ESTs (e.g. discovery of new functional motifs).
Transient electrohydrodynamics of compound drops

The transient electrohydrodynamics of a compound drop under a uniform electric field of small strength is investigated. A closed form analytical solution is developed for creeping flow regimes and fluid systems and drop sizes with moderate and/or large Ohnesorge numbers, in the framework of leaky dielectric theory. For small distortion from a spherical shape, the inner and the outer drops deform to ellipsoids, and their deformation–time histories can be represented by $${\mathcal{D}_{ij}=A_{ij} {\rm exp}(-t/\tau_1) + B_{ij} {\rm exp}(-t/\tau_2) + \mathcal{D}^\infty_{ij}}$$ , where ij = 12,23 refers to the surfaces of the inner and the outer drops, $${\tau_1}$$ and $${\tau_2}$$ are the characteristic times, A i j and B i j are the coefficients that depend on the input parameters of the system, and $${\mathcal{D}^\infty_{ij}}$$ are the steady-state deformation parameters. The evolution of the flow field for several fluid systems was explored, and it was shown that the ratios of electric conductivities and permittivities of the participating fluids play a key role in determining the evolution of the flow field toward the steady state and that the steady-state flow is established by the motion of toroidal vortices that are formed in the drops and move outward, or formed in the ambient fluid and move inward.
The incidence and progression of pneumoconiosis over nine years in U.S. coal miners: I. Principal findings.

Chest radiographs, taken at a 9-year interval for 1,261 U.S. coal miners, were read for pneumoconiosis side-by-side by six readers in a controlled trial. Incidence and progression of small, rounded opacities were consistent with levels predicted from dose-response curves developed by the British Pneumoconiosis Field Research interpolated at a concentration derived from U.S. compliance levels mandated over the last 9 years. The results imply that the level of pneumoconiosis in U.S. miners is being reduced through application of the current 2 mg/m3 standard. The long developmental period for pneumoconiosis necessitates that further study be undertaken to verify this finding and to determine whether 2 mg/m3 is an appropriate regulatory dust level for the prevention of category 2 or greater simple pneumoconiosis over a 35-year period.
Rosette-forming ability of alveolar macrophages from rat lung: inhibition by hexachlorobenzene.

Abstract Adult male rats were fed diets containing 250 ppm hexachlorobenzene. They were maintained on this diet for 8–10 weeks, at which time they were killed and alveolar macrophages were washed from their lungs. The antibody-binding ability (F c receptor activity) of these cells was measured by quantitating the percentage of rosette formation at fixed antibody concentrations. Rosette formation by cells recovered from hexachlorobenzene-treated rats was distinctly lower than that from untreated rats.
CCR7 mediates inflammation-associated tumor progression

Chemokine receptor 7 (CCR 7) mediates leukocyte adhesion and chemotaxis from peripheral sites of inflammation through lymphatic channels to secondary lymphoid organs. Aberrant CCR7 expression has been identified on certain tumor types and been linked to pro-survival and invasive pathways. In metastatic squamous cell carcinoma of the head and neck (SCCHN), we have described the selective upregulation of functional CCR7. In this manuscript, we review our understanding of CCR7-mediated signaling in metastatic SCCHN and provide evidence for its involvement in tumor survival, invasion, and metastasis. Autocrine and paracrine CCR7 activation appears to propagate the response to the CCR7 ligands CCL19 and CCL21, which are expressed by the lymphatic endothelium, secondary lymphoid tissues, and CCR7-positive tumor cells. Based on our recent findings, the induction of CCR7 expression and the sustenance of the autocrine signaling pathway have been shown to be regulated by NF-κB, similar to several types of immune cells. While extending these observations to metastatic SCCHN tumor cells, our studies highlight the importance of downstream NF-κB mediated CCR7 signals in the progression of SCCHN malignancy.
Report on stage III Pig-a mutation assays using benzo[a]pyrene.

Genotoxicity assays were conducted on rats treated with benzo[a]pyrene (BaP) as part of Stage III of a validation study on the Pig-a gene mutation assay. Assays were performed at the U.S. FDA-NCTR and Bayer-Germany. Starting on Day 1, groups of five 6- to 7-week-old male Fischer 344 (F344, used at FDA-NCTR) and Han Wistar rats (Bayer) were given 28 daily doses of 0, 37.5, 75, or 150 mg/kg BaP; blood was sampled on Days −1, 4, 15, 29, and 56. Pig-a mutant frequencies were determined on Days −1, 15, 29, and 56 in total red blood cells (RBCs) and reticulocytes (RETs) as RBCCD59− and RETCD59− frequencies; percent micronucleated-RETs (%MN-RET) were measured on Days 4 and 29. RBCCD59− and RETCD59− frequencies increased in a dose- and time-dependent manner, producing significant increases by Day 29 in both rat models. The responses for RETs were stronger than those for RBCs, and the responses in F344 rats were stronger than in Han Wistar rats. BaP also produced significant increases in %MN-RET frequency at Days 4 and 29, with the responses being greater in F344 than Han Wistar rats. The overall findings were consistent with those of the reference laboratory using Han Wistar rats. Finally, mutation assays performed on splenocytes from Day 56 F344 rats indicated that BaP mutant frequencies were three to fivefold higher for the Hprt gene than the Pig-a gene. The results indicate that the Pig-a RET and RBC assays are reproducible, transferable, and show promise for integrating gene mutation into 28-day repeat-dose studies. Environ. Mol. Mutagen. 2011. © 2011 Wiley-Liss, Inc.
A technique for fabrication of polydimethylsiloxane-acrylic resin obturators

A flexible silicone obturator is an alternative to the acrylic resin obturator. It can be useful for patients with severe trismus who cannot insert a large prosthesis, as the flexibility of the hollow silicone section allows easy placement and removal (Fig. 9). Other patients cannot tolerate an unyielding substance against sensitive nasal tissues. Silicone can provide the necessary comfort without compromising retention. Silicone obturator sections can often be modified when further surgery is needed and result in a savings of time and expense (Fig. 10). For patients who can be reevaluated only twice a year, several silicone obturator sections can be made initially. One can be used while another is being cleaned or duplicated.
Erratum to: The Routine Use of Atypical Cultures in Presumed Aseptic Revisions Is Unnecessary

The online version of the original article can be found under doi:10.1007/s11999-013-2917-7.
Effect of 1-aminocyclopropane-1-carboxylic acid on maize kernel development in vitro

Pollination stimulates ethylene production in maize ears, and the application of ethephon during the pollination period can cause kernel abortion. The objective of this study was to determine if kernel abortion could be induced in vitro by the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC). Adding ACC to the culture medium resulted in the evolution of ethylene which caused abortion and reduced mature kernel mass. The effect of ethylene on kernel abortion and dry matter accumulation was partially negated by the addition of the ethylene-binding site inhibitor, 2,5-norbornadiene (NBD). The effect of ethylene on kernel abortion was greatest during the early stage of kernel development and was intensified by an increase in media sucrose concentration. These data suggest that ethylene could regulate kernel abortion in maize.
Naltrindole, a selective δ-opioid receptor antagonist, potentiates the lethal effects of cocaine by a central mechanism of action

The potentiation of the toxic and lethal effects of cocaine by the selective delta-opioid receptor antagonist naltrindole was explored in unrestrained, unanesthetized rats that received a continuous intravenous infusion of cocaine until death. The lethal dose of cocaine was lowered dose dependently in animals administered naltrindole intracisternally (3.0-30 microg), but not intravenously (30-300 microg). There was also a decrease in the lethal dose of cocaine following an injection of the nonselective opioid antagonist naltrexone, but not naloxone. However, the seizure-producing dose of cocaine was decreased dose dependently in rats that received naltrindole, regardless of the route of administration, naloxone, or naltrexone. In contrast, the effect of cocaine on heart rate was altered only by centrally administered naltrindole or intravenous naltrexone, with a dose of 30 microg naltrindole and 10 mg/kg naltrexone abolishing the bradycardic effect of cocaine. Despite this, neither naltrindole nor naltrexone changed the hypertensive effect of cocaine. Higher doses of naltrindole (100 microg i.c.) produced significant increases in heart rate and mean arterial pressure and were not tested in combination with cocaine. Because the lethal dose of cocaine was reduced only when naltrindole was administered intracisternally, the potentiation of the lethal effects of cocaine by naltrindole is through a central mechanism of action that may involve changes in cardiovascular function.
Puncture Tests on Porcelain Distribution Insulators Using Steep-Front Voltage Surges [includes discussion]

The primary objective was to develop a laboratory test to discriminate between insulators liable to puncture and shatter and those which satisfactorily discharge the stroke by flashover and continue to operate normally after the momentary ground has been cleared. It was established that insulator failure by puncture could be obtained by repeated applications of a steeply rising voltage surge to the test specimen
Component measures of psychological sense of community among gay men

Psychological Sense of Community (PSOC) theoretically comprises four components (Membership, Influence, Fulfillment of Needs, and Shared Emotional Connection), but existing measures of the components are psychometrically lacking. The current study sought to develop valid and reliable measures of the four theoretical components by building on and conceptually tightening items from existing PSOC measures, including the Sense of Community Index. Twenty-six items were administered to 348 gay and bisexual men living in Arizona. Using exploratory and confirmatory factor analysis, a three-factor model with Influence, Shared Emotional Connection, and Fulfillment of Needs/Belonging achieved the best fit; it was impossible, empirically, to distinguish between the Fulfillment of Needs and Belonging factors. Measures for these three PSOC components and the combined PSOC measure evidenced high reliabilities. Validity testing results supported the three component measures and the combined measure. Implications of the results for PSOC theory and research are discussed. © 2006 Wiley Periodicals, Inc.
The effect of intensive bimanual training on coordination of the hands in children with congenital hemiplegia

Recent studies have suggested efficacy of intensive bimanual training in improving the quality and quantity of affected hand use in children with hemiplegia. However, it is not known whether such training affects the coordination of the two hands. In the present study, 20 children with congenital hemiplegia (age 4-10 years; MACS levels I-II) were randomly assigned to either an intensive bimanual training (Hand-Arm Bimanual Intensive Therapy: HABIT) group, or a control group consisting of equally intensive unimanual treatment (Constraint-Induced Movement Therapy, CIMT) for 6h per day for 15 days (90h). To assess their bimanual coordination, children were asked to open a drawer with one hand and manipulate its contents with the other hand. 3-D movement kinematics were recorded and subsequently analyzed by a blind evaluator. The role of the two hands was varied. Following treatment, superior improvement in bimanual coordination was found for the bimanual training group as indicated by greater movement overlap (the percentage of time with both hands engaged in the task p = 0.047) and better goal synchronization (reduced time differences between the two hands completing the task goals, p = 0.005). The results suggest that bimanual training improves the spatial-temporal control of the two hands, and are in agreement with the principle of practice specificity.
Betulin and lupeol in bark from four white-barked birches

Abstract Levels of betulin in the outer bark of four species of white-barked birch range from 5.0 to 22.0%. This variation in the level of betulin is taxonomically useful. The percentage of betulin in chloroform extracts is significantly different between two taxa, Betula cordifolia and B. papyrifera , that are often considered conspecific. In B. X caerulea , a putative hybrid of B. cordifolia and B. populifolia , betulin levels are intermediate between and significantly different from those of the parents. Levels of the codominant triterpenoid, lupeol, are less than 1.3% and are significantly different only between B. populifolia and B. X caerulea .
The Influence of Comorbid Depression and Conduct Disorder on MET/CBT Treatment Outcome for Adolescent Substance Use Disorders.

Although depression and conduct disorder frequently co-occur with substance use disorders (SUDs), few studies have investigated the individual and interactive effects of these conditions on SUD treatment outcome. Data were collected from 90 adolescents aged 13–21 (M = 17.1, SD = 2.07) who received a brief evidence-based intervention for SUD. Hierarchical regressions assessed the relationship among demographic variables, depression, conduct disorder, and two substance use outcomes (frequency and problems) at two intervals (three months, six months). Results revealed that higher baseline substance use and lower socioeconomic status significantly predicted higher substance problems and frequency at three months. At six months, higher three-month substance problems and lower depressive symptoms predicted substance problems. In addition, an interaction indicated that the effect of conduct disorder on substance problems was greatest at lower levels of depression. Results are discussed in the context of previous...
Effects of serial programs in multiprocessing systems

A model of a multiprocessing, multiprogramming computer system with serially reusable programs was developed to study the effect of serial programs on system performance. Two strategies for implementing serially reusable programs were investigated, a wait strategy in which the processor waits until the serial program is available, and a switch strategy, in which the processor is freed to do other work. Relative performances and asymptotic conditions as functions of the number of processors, processes, serially reusable programs, and the fraction of time each process executes serially reusable programs were obtained. Quantitative results are presented showing that the switch strategy is superior. The wait strategy causes quick saturation when the number of processes is increased.
Phytotoxin Produced by Nimbya scirpicola

A phytotoxic substance isolated from the weed pathogen Nimbya scirpicola was identified as depudecin by spectral data nalyses. It was found that depudecin had phytotoxic activity toward the host plant of this fungus, kuroguwai, and toward other tested plants, and inhibited the root elongation of lettuce seedlings.
Studies of lactose absorption in patients with galactosemia

Ten patients with galactosemia and six control subjects were given oral lactose loads. Only one child, a patient with galactosemia, failed to hydrolyze lactose and absorb its monosaccharide components. Nine of ten patients with galactosemia hydrolyzed lactose in spite of the fact that lactose had been excluded from their diet since early infancy, which suggested that intestinal lactase does not appear to be dependent upon lactose intake. The results of the sugar tolerance tests and of jejunal enzyme studies indicated that one of the children with galactosemia had an isolated lactase defect.
The curious institution of mobile home rent control

Abstract This paper analyzes the implications of rent control as applied to dwellings located in mobile home parks. This form of regulation differs from apartment rent control in that: it is applied selectively to a small portion of the housing stock, and; it regulates the site rents paid to the park owner, not the selling prices or monthly rents on mobile homes. We present a detailed case study of the effects of this institution in three mobile home parks in different cities and regions in California, documenting the capitalization of regulatory rules into the selling prices of housing, and raising questions about the legality as well as the efficacy of the institution.
Validation and implementation of a liquid chromatography/tandem mass spectrometry assay to quantitate ON 01910.Na, a mitotic progression modulator, in human plasma.

Abstract A reverse-phase high performance liquid chromatographic method with tandem mass spectrometry (LC–MS/MS) was developed and validated for the quantitation of ON 01910.Na, a novel synthetic benzyl styryl sulfone, in human plasma. The assay involved a simple sample preparation with acetonitrile protein precipitation. ON 01910.Na and the internal standard temazepam were separated on a Waters X-Terra™ MS C 18 column with mobile phase of acetonitrile containing 0.1% formic acid /10 mM ammonium acetate (55:45, v/v) using isocratic flow at 0.2 mL/min for 5 min. The analytes were monitored by tandem-mass spectrometry with electrospray positive ionization. Two calibration curves were generated over the range of 10–2000 ng/mL and 100–20000 ng/mL. The lower limit of quantitation (LLOQ) was 10 ng/mL for ON 01910.Na in human plasma. The accuracy and within- and between-day precisions were within the acceptance criteria for bioanalytical assays. ON 01910.Na was found stable in plasma at −70 °C for at least 1 year. The method was successfully applied to characterize the plasma concentration–time profiles of ON 01910.Na in the cancer patients in the Phase I study.
Density and heat capacity of liquid uranium at high temperatures

Abstract Measurements of volume expansion, temperature, resistivity and enthalpy have been made for liquid uranium from 2632 to 5408 K by the isobaric expansion technique wherein a wire surrounded by inert gas is heated with a current pulse, and measurements are made quickly before the liquid column collapses. The heat capacity found for the liquid is 0.047 kJ/mol K, and the volume thermal expansion coefficient is 99 × 10 −6 per K. It was also observed that the solid phase transitions occurred as equilibrium transitions at heating rates of approximately 130 million degrees per second.
Effect of increased cost-sharing on oral hypoglycemic use in five managed care organizations: how much is too much?

Background:For patients with a chronic disease, increased cost-sharing for medications may lead to unintended consequences, including reduced use of medications essential for control of their disease.Objective:The objective of this study was to estimate the effects of small ($1–6 per 30-day supply),