cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of histatin-1 peptide on human corneal epithelial cells.

Purpose Ocular surface and corneal epithelial wounds are common and potentially debilitating problems. Ideal treatments for these injuries would promote epithelial healing without inflammation, infection and scarring. In addition the best treatments would be cost-efficient, effective, non-toxic and easily applied. Histatin-1 peptides have been shown to be safe and effective enhancers of epithelial wound healing in other model systems. We sought to determine whether histatin-1 peptides could enhance human corneal epithelial wound healing in vitro. Methods Histatin-1 peptides were applied to human corneal epithelial cells and compared over useful dose ranges in scratch assays using time-lapse microscopy. In addition, path finding analysis, cell spreading assays, toxicity and proliferation assays were performed to further characterize the effects of histatin-1 peptide on human corneal limbal epithelial (HCLE). Results Histatin-1 enhanced human corneal epithelial wound healing in typical wound healing models. There was minimal toxicity and no significant enhancement of proliferation of corneal epithelium in response to histatin-1 application. Corneal epithelial spreading and pathfinding appeared to be enhanced by the application of histatin-1 peptides. Conclusions Histatin -1 peptide may enhance migration of HCLE cells and wound healing in vitro. These peptides may have benefit in corneal epithelial wounds and need to be investigated further.
Accelerated Changes in Cortical Thickness Measurements with Age in Military Service Members with Traumatic Brain Injury

Finding objective and quantifiable imaging markers of mild traumatic brain injury (TBI) has proven challenging, especially in the military population. Changes in cortical thickness after injury have been reported in animals and in humans, but it is unclear how these alterations manifest in the chronic phase, and it is difficult to characterize accurately with imaging. We used cortical thickness measures derived from Advanced Normalization Tools (ANTs) to predict a continuous demographic variable: age. We trained four different regression models (linear regression, support vector regression, Gaussian process regression, and random forests) to predict age from healthy control brains from publicly available datasets (n = 762). We then used these models to predict brain age in military Service Members with TBI (n = 92) and military Service Members without TBI (n = 34). Our results show that all four models overpredicted age in Service Members with TBI, and the predicted age difference was significantly greater compared with military controls. These data extend previous civilian findings and show that cortical thickness measures may reveal an association of accelerated changes over time with military TBI.
Trichloroacetic Acid Ingestion: Self-Harm Attempt

Objective. Trichloroacetic acid (TCAA), or trichloroethanoic acid, is a chemical analogue of acetic acid where three methyl group hydrogen atoms are replaced by chlorine. TCAAs are also abbreviated and referred to as TCAs, causing confusion with the psychiatric antidepressant drug class, especially among patients. TCAAs exist in dermatological treatments such as chemical peels or wart chemoablation medication. TCAA ingestion or overdose can cause gastric irritation symptoms including vomiting, diarrhea, or lassitude. This symptomatology is less severe than TCA overdose, where symptoms may include elevated body temperature, blurred vision, dilated pupils, sleepiness, confusion, seizures, rapid heart rate, and cardiac arrest. Owing to the vast difference in symptoms, the need for clinical intervention differs greatly. While overdose of either in a self-harm attempt can warrant psychiatric hospital admission, the risk of death in TCAA ingestion is far less. Case Report. A patient ingested TCAA in the form of a commercially available dermatological chemical peel as a self-harm attempt, thinking that it was a more injurious TCA. Conclusion. Awareness among physicians, particularly psychiatrists, regarding this relatively obscure chemical compound (TCAA) and its use by suicidal patients mistakenly believing it to be a substance that can be significantly more lethal (TCA), is imperative.
Principal Effectiveness and Principal Turnover

Research demonstrates the importance of principal effectiveness for school performance and the potentially negative effects of principal turnover. However, we have limited understanding of the fact...
Supervised classification methods for mining cell differences as depicted by Raman spectroscopy

Discrimination of different cell types is very important in many medical and biological applications. Existing methodologies are based on cost inefficient technologies or tedious one-by-one empirical examination of the cells. Recently, Raman spectroscopy, a inexpensive and efficient method, has been employed for cell discrimination. Nevertheless, the traditional protocols for analyzing Raman spectra require preprocessing and peak fitting analysis which does not allow simultaneous examination of many spectra. In this paper we examine the applicability of supervised learning algorithms in the cell differentiation problem. Five different methods are presented and tested on two different datasets. Computational results show that machine learning algorithms can be employed in order to automate cell discrimination tasks.abstract
C-1015: Implications of the consequences of laser-induced ultra-rapid warming of mouse oocytes and embryos to vitrification theory and to the successful vitrification of other cell types

Jin, Kleinhans, and Mazur have reported in this meeting that up to 100% of oocytes and 2-cell embryos survive vitrification in a 3-fold dilution of EAFS medium if warmed at 10,000,000 °C/min by an IR laser pulse. The usual cooling rate was 69,000 °C/min, but 95% also survived when cooled at 10,000 °C/min. Thus, survival is far more dependent on the rate of warming than on the rate of cooling, the reason being that very high warming rates prevent or impede the recrystallization of intracellular ice. In all our experiments, the oocytes or embryos were held for 2.0 min in 1/3 × EAFS before vitrification That time was chosen because Pedro (1997) found it to produce the best survival after vitrification. EAFS media are strongly hyperosmotic so that oocytes/embryos placed in them, undergo an osmotic shrink-swell pattern with time. There is an initial rapid shrinkage to a minimum volume due to water loss, followed by a much slower re-swelling due to the slow influx of the permeating solutes. Based on Pedro’s data, that minimum occurs near 2 min, and osmotic theory argues that at that point, the cells have lost 85% of their original water and very little permeating solute has entered them. The strong inference, then, is that the high subsequent survivals are a consequence of the 85% osmotic dehydration and are not due to the intracellular presence of permeating solutes. Supporting that conclusion is Jin and Mazur’s report that 77% of oocytes and 95% of 2-cell and 8-cell embryos survive vitrification when suspended in media containing only the non-permeating solutes sucrose provided they are warmed at 1 × 107 °C/min by a pulse from our IR laser. None survived when warmed 100× more slowly in the absence of the laser. These findings are at odds with orthodox beliefs about the causes of injury from vitrification. They could possibly open the way to the successful vitrification of important cell types that to date have been partially or fully refractory to this approach.
Meaning and Value: Reflections on What Students Say About School (1993)

This study examines how high school students in dance make sense of their experiences, using a methodology of interpretive inquiry. Based on field work in five different dance classes, taught by three teachers at two high schools, most of the data comes from extensive interviews conducted with the 36 students who chose to participate and returned consent forms. The researcher identifies two major themes, one having to do with relationships (with dance classes often described as a safe and idealized home and/or family, providing supportive teacher and peer relationships), the second with how students construct meaning and value from their school experiences. Through the data emerges what students say they desire from school: To be stimulated, to learn; To have a sense of meaning in what they are being taught; To be treated with understanding, to be cared for; and To be able to be themselves. This involves conditions of both security (being accepted as they ought to be in their own family) and freedom (to express themselves).
Understanding the Nature of Violence: Crime and Its Future

This chapter explores the nature and types of violence the world suffers from today. Physical acts of violence such as war and terrorism, structural violence like poverty and economic deprivation, and violence against women and children, including sexual abuse, are examined. The chapter sees violence as an act of communication by various groups (e.g., organized crime groups), as they seek to convey some message to the world. For instance, criminal groups can use violence to scare rivals and intimidate citizens from reporting corrupt acts to the police or journalists from publishing stories about illicit activities. The chapter concludes by questioning if we will ever see the end of violence.
Association between household poverty dynamics and childhood overweight risk and health behaviours in the United States: a 8‐year nationally representative longitudinal study of 16 800 children

BACKGROUND No study has examined how the pattern of income dynamics influences both of children's body mass index (BMI) trajectory and health behaviours. OBJECTIVES To examine the association between household poverty dynamics and childhood overweight risk in the USA. METHODS Using the longitudinal data of 16 800 children (from kindergarten to the 8th grade) in the nationally representative US cohort-Early Childhood Longitudinal Study, Kindergarten Class 1998-1999, we examined the differences in BMI trajectory, weight-related health behaviours and risk of overweight in association with household poverty dynamics during follow-up (never [no experience of poverty], transient [once], recurrent [≥2 times] and persistent poor [remained]) using mixed models with fractional polynomial functions and estimating equation models. RESULTS Overall, children experiencing poverty were more likely to have adverse BMI growth trajectory and eating and sedentary behaviours compared with the never poor. The recurrently poor children (12.8%) had the fastest BMI trajectory, highest overweight/obesity prevalence from 5 to 16 years old and highest proportion of excessive soda/fast food consumption and irregular exercise at 8th grade than did others (p < 0.05). The persistently poor (8.4%) were the lowest in BMI growth trajectory but became the second highest in childhood obesity through a steady increase in BMI over time. Children in the recurrently poor group had a 1.5 times (95% CI = 1.0-2.2) higher risk of overweight than those having never experienced poverty during follow-up. CONCLUSIONS The experience of recurrent household poverty had a significant association with children's adverse eating behaviours and increased obesity risk subsequently.
A large assemblage of tetrapod tracks from the Cretaceous Naturita Formation, Cedar Canyon region, southwestern Utah

Abstract A large assemblage of more than 100 archosaur tracks was recovered from the Cretaceous “Dakota Formation” (Naturita Formation) at a high elevation site on private land in the Cedar Canyon area of southwestern Utah. The assemblage is notable for several reasons. It consists exclusively of large, deep, and well preserved natural casts. All three major groups of archosaurs are represented: dinosaurs, pterosaurs and crocodylians. Non-avian theropod (Magnoavipes), ankylosaurian (Tetrapodosaurus), ornithopod (Caririchnium) and crocodylian swim tracks are all represented abundantly, in similar proportions. Both swim tracks and crocodilian walking tracks are represented, the former assigned to Hatcherichnus are common, but the latter assigned to Mehliella are rare. The assemblage also contains a few pterosaur tracks (Pteraichnus). The composition of the assemblage is very similar to that found in the Naturita Formation in western Colorado, where a Cenomanian age is reported. This is the most westerly occurrence of an assemblage with this distinctive composition, and suggests a vast paleogeographical extension of the so called Dakota megatracksite or dinosaur freeway.
Measuring Attitudes toward Energy Conservation: Cynicism, Belief in Material Growth, and Faith in Technology:

Several recent studies have attempted to use factor analysis to determine the underlying dimensions of attitudes toward energy conservation. This research takes a different approach. Milstein [1979...
QUANTITATIVE P WAVE CHARACTERISTICS DURING SINUS RHYTHM ARE ALTERED BY CAVO-TRICUSPID ISTHMUS ABLATION

Typical atrial flutter is a common arrhythmia that is effectively treated with ablation at the cavotricuspid-isthmus (CTI) to achieve bidirectional conduction block. Currently, bidirectional block can only be assessed by intracardiac pacing maneuvers. We hypothesized that quantitative
MRI impacts endometriosis management in the setting of image-based multidisciplinary conference: a retrospective analysis

The aim of the study was to quantify the value of pre-operative magnetic resonance imaging (MRI) in guiding surgical management of women with endometriosis. Pre-operative discussion of patient management and review of imaging occurred for 136 patients with endometriosis in an MRI-based multidisciplinary conference co-directed by an abdominal radiologist and gynecologic surgeon. A tri-compartmental report template guided the systematic imaging review. Management changes made as a result of the conference were identified via retrospective chart review and classified as major, directly influencing the surgical procedure or approach, or minor, impacting the patient’s medical management, therapies, or diagnostic evaluation. Of the 136 patients discussed in conference, a management change was identified in 18.4% (25 patients). Major changes occurred in 8.1% (11 patients) and minor changes in 13.2% (18 patients). The sum of major and minor management changes exceeded the total, as both major and minor management changes were made for 4 patients. Our findings demonstrate the ability of an MRI-based multidisciplinary conference to result in pre-operative management changes in approximately 1 of 5 pre-operatively reviewed women with endometriosis. Importantly, systematic review of the MRI facilitated management changes beyond that of the dictated report alone, which was available to clinicians prior to the conference. The study reflects the value of multidisciplinary interaction, with radiologists serving more directly as clinical consultants to surgical services, and suggests an opportunity to optimize the role of MRI in endometriosis management with standardized reports emphasizing surgically pertinent findings.
Damage mechanism on vascular endothelium by platelet-derived microparticle

Platelet-derived microparticle (PMP)is a heterogeneous vesicle (<1 μm)generated from the plasma membrane when platelets are activated by various stimulation, which is composed of serous cystic fragments and α-granules.The formation, release and level of circulating PMP can reflect the platelet activation.The functions of PMP include facilitating coagulation, promoting adhesion of platelet and leukocyte to the subendothelial membrane, promoting angiogenesis and stimulating the proliferation of vascular smooth muscle.High level of PMP appears in many cardiovascular diseases such as atherosclerosis, diabetes mellitus, Kawasaki disease and so on.This paper is to review the mechanism of PMP in the vascular endothelial injury. Key words: Platelet-derived microparticles; Vascular endothelium; Atherosclerosis; Diabetes mellitus; Kawasaki disease
Dalbavancin exposure in vitro selects for dalbavancin-non-susceptible and vancomycin-intermediate strains of methicillin-resistant Staphylococcus aureus.

Abstract Objectives Dalbavancin is a lipoglycopeptide active against methicillin-resistant Staphylococcus aureus (MRSA). Its long half-life (8.5–16 days) allows for once-weekly or single-dose treatments but could prolong the mutant selection window, promoting resistance and cross-resistance to related antimicrobials such as vancomycin. The objective of this study was to evaluate the capacity of post-distributional pharmacokinetic exposures of dalbavancin to select for resistance and cross-resistance in MRSA. Methods We simulated average, post-distributional exposures of single-dose (1500 mg) dalbavancin (fCmax 9.9 μg/mL, β-elimination t1/2 204 h) in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model for 28 days (672 h) against five MRSA strains and one methicillin-susceptible strain (MSSA). Samples were collected at least daily, and surviving colonies were enumerated and screened for resistance on drug-free and dalbavancin-supplemented medium respectively. Isolates from resistance screening plates were subjected to whole-genome sequencing (WGS) and susceptibly testing against dalbavancin, vancomycin, daptomycin, and six β-lactams with varying penicillin-binding protein (PBP) affinities. Results Dalbavancin was bactericidal against most strains for days 1–4 before regrowth of less susceptible subpopulations occurred. Isolates with eight-fold increases in dalbavancin MIC were detected as early as day 4 but increased 64–128-fold in all models by day 28. Vancomycin and daptomycin MICs increased 4–16-fold, exceeding the susceptibly breakpoints for both antibiotics; β-lactam MICs generally decreased by two-to eight-fold, suggesting a dalbavancin–β-lactam seesaw effect, but increased by eight-fold or more in certain isolates. Resistant isolates carried mutations in a variety of genes, most commonly walKR, apt, stp1, and atl. Conclusions In our in vitro system, post-distributional dalbavancin exposures selected for stable mutants with reduced susceptibility to dalbavancin, vancomycin, and daptomycin, and generally increased susceptibility to β-lactams in all strains of MRSA tested. The clinical significance of these findings remains unclear, but created an opportunity to genotype a unique collection of dalbavancin-resistant strains for the first time. Mutations involved genes previously associated with vancomycin intermediate susceptibility and daptomycin non-susceptibility, most commonly walKR-associated genes.
Privacy in Crisis: Participants' Privacy Preferences for Health and Marketing Data during a Pandemic

The severity of COVID-19 and the need for contact tracing has resulted in new urgency for investigating two mutually exclusive narratives about the importance of privacy. The assertion by some technology advocates that privacy is no longer an issue in the face of a pandemic has been repeatedly reported; while others advocated for its centrality. The rejection of contact tracing apps, in part because of privacy, has also been widely reported. Simultaneously, different tracing apps implement different conceptions of privacy. For any contact tracing app to function the technology must provide security and privacy implementations that are usable and acceptable. Towards that goal, we sought to better understand risk perceptions about data use during a public health crisis. To do this we conducted a between-subject online survey to identify participants' risk perceptions about their data being collected and shared during a public health crisis. The survey results do not support claims in prior work that people are comfortable with sharing their private information during a public health crisis; but instead offered nuanced responses depending on type of information, purpose of use, and recipient, thus reifying previous work rather than suggesting a fundamental difference. We note that participants' privacy risk perceptions remain similar whether data are to be used to address health risks or for traditional marketing. Finally, our findings show that device type, not just data type, should be taken into account when designing a tracing app that aligns with participants' privacy perceptions.
The impact of voter initiatives on economic activity

Abstract Recent studies have claimed that states with initiative systems of legislation use this more direct form of democracy to improve productive resource allocation. This paper compares the economic performance of states with initiatives to states that do not have initiatives. We first construct a simple growth model to identify the channel through which initiatives play an important role in determining economic activity; we then test the implications of this model using data for the 48 contiguous United States over the years 1969–1986. Our findings suggest that states with initiative systems waste between 20% and 30% fewer resources than do non-initiative states resulting in better economic performance in terms of higher GDP growth and faster convergence.
GraphGuess: Approximate Graph Processing System with Adaptive Correction.

Graph-based data structures have drawn great attention in recent years. The large and rapidly growing trend on developing graph processing systems focus mostly on improving the performance by preprocessing the input graph and modifying its layout. These systems usually take several hours to days to complete processing a single graph on high-end machines, let alone the overhead of pre-processing which most of the time can be dominant. Yet for most of graph applications the exact answer is not always crucial, and providing a rough estimate of the final result is adequate. Approximate computing is introduced to trade off accuracy of results for computation or energy savings that could not be achieved by conventional techniques alone. Although various computing platforms and application domains benefit from approximate computing, it has not been thoroughly explored yet in the context of graph processing systems. In this work, we design, implement and evaluate GraphGuess, inspired from the domain of approximate graph theory and extend it to a general, practical graph processing system. GraphGuess is essentially an approximate graph processing technique with adaptive correction, which can be implemented on top of any graph processing system. We build a vertex-centric processing system based on GraphGuess, where it allows the user to trade off accuracy for better performance. Our experimental studies show that using GraphGuess can significantly reduce the processing time for large scale graphs while maintaining high accuracy.
An approximate approach to the unsplittable flow edge load factor balancing problem with the Lagrangian relaxation

This study has focused on the UELB problem that aims at leveling the traffic load of a communication link in an information network by determining the path of a flow that minimizes the maximum load factor of the link. The UELB problem has been proved to be NP-hard, and an approximate solution method using the LP relaxation has been proposed to verify the results. This paper proposes another algorithm using the Lagrangian relaxation method in order to objectively evaluate the accuracy of the approximate solutions obtained so far. We have conducted comparison experiments with the method using LP relaxation. The result has demonstrated that the proposed algorithm has relatively higher computational complexity and taken a long time to calculate the solution because of using the subgradient method for the Lagrangian relaxation. In addition, it is indicated that both the conventional LP relaxation and the proposed algorithm are effective because they are close to the exact solution.
The Photochemistry of NH3 in the Jovian Atmosphere

Abstract A quantitative study of the photochemistry of NH3 above the Jovian tropopause is given. The NH3, density distribution is described by two relevant vertical scales: Hav the scale height of the background atmosphere, and (K/Jnet½ the “photomechanical” scale height, where K is the eddy diffusion coefficient and Jnet> the net destruction rate of NH3.In the case of slow mixing, substantial photochemical destruction of NH3 occurs and the NH3 density profile departs significantly from a mixed distribution. Comparison of the observed and calculated UV albedos of Jupiter suggests a value of K≈2×104 cm2 sec −1 is appropriate in the lower stratosphere. Radiative excitation of NH2 radicals to the A state is unimportant in the NH3 photochemistry. A slow circulation that transports N2H4 to the hotter, dense regions of the eep atmosphere, where it undergoes thermal decomposition to NH2 radicals which react with H2 to form fresh NH3, is invoked to explain the continued presence of NH3 on Jupiter. It is suggested...
The Activation of Fatty Acids in Castor Bean Endosperm

Abstract The demonstration that the reactions of β oxidation and the glyoxylate cycle occur in the glyoxysome, a cellular organelle isolated from castor bean endosperm, has raised the question of the intracellular location of the enzymatic activation of free fatty acids in this tissue. Glyoxysomes, isolated on sucrose gradients, have been shown to contain a thiokinase which, in the presence of CoA, MgCl2, and ATP (GTP is ineffective), activates free fatty acids to their cognate fatty acyl-CoA derivatives. The thiokinase is specific for fatty acids of chain length greater than C-10. An acetate thiokinase was also found in glyoxysomes. It is specific for ATP and is more tightly bound to the organelles than the long chain thiokinase. Although the long chain thiokinase is easily solubilized, the data show that the intact glyoxysomes can convert free fatty acids to their CoA derivatives and oxidize them to acetyl-CoA.
Using data mining and judgment analysis to construct a predictive model of crime

This paper discusses the use of cognitive psychology and data mining to construct a predictive model of crime. This model predicts from the location, time, and daily mean temperature whether the theft was of a bicycle, a firearm, or a purse. It also discovers the features that were salient to the choice of a target for these three crimes. The model was constructed for Richmond, Virginia. In this analysis association rules were used to construct an independent set of crimes. Then a classification and regression tree methodology was used to create a classification tree. This tree was used in a predictive model that, given the location of the crime, the mean air temperature on that day, and the time oft he crime, predicted the type of item stolen. The resulting model predicted the object of the theft with accuracy significantly above that of a random draw.
Mining Possibilistic Set-Valued Rules by Generating Prime Disjunctions

We describe the problem of mining possibilistic set-valued rules in large relational tables containing categorical attributes taking a finite number of values. An example of such a rule might be “IF HOUSEHOLDSIZE={Two OR Tree} AND OCCUPATION={Professional OR Clerical} THEN PAYMENT_METHOD={CashCheck (Max=249) OR DebitCard (Max=175)}. The table semantics is supposed to be represented by a frequency distribution, which is interpreted with the help of minimum and maximum operations as a possibility distribution over the corresponding finite multidimensional space. This distribution is approximated by a number of possibilistic prime disjunctions, which represent the strongest patterns. We present an original formal framework generalising the conventional boolean approach on the case of (i) finite-valued variables and (ii) continuos-valued semantics, and propose a new algorithm, called Optimist, for the computationally difficult dual transformation which generates all the strongest prime disjunctions (possibilistic patterns) given a table of data. The algorithm consists of generation, absorption and filtration parts. The generated prime disjunctions can then be used to build rules or for prediction purposes.
Examining O-xylosyltransferase shedding in Drosophila (539.1)

O-xylosyltransferase (Oxt) is a Golgi transmembrane glycosyltransferase that initiates the first step in the heperan and chrondroitin sulfate biosynthesis on core proteoglycans (HSPG and CSPG). HSP...
The Liabilities of Iron Deficiency

Iron has been recognized as a potent hematinic since the inception of hematology as a clinical discipline. Even ancient civilizations believed in the beneficial effects of medicinal iron. Nevertheless, the precise functional liabilities of iron lack remain the subject of continuing debate. The consequences of iron deficiency, particularly from a socioeconomic standpoint, are especially important in light of its high global prevalence. A recent review of the literature indicates that approximately 30% of the estimated world population of nearly 4.5 billion are anemic, and at least half of these, 500 to 600 million people, are believed to have iron deficiency anemia.
Emotional and behavioral difficulties and impairments in everyday functioning among children with a history of attention-deficit/hyperactivity disorder.

Introduction Attention-deficit/hyperactivity disorder (ADHD) affects 3% to 7% of school-aged children and has been associated with a variety of comorbid mental illnesses and functional impairments, largely in clinical samples. However, little is known about the spectrum of emotional and behavioral problems and areas of impairment among children with a history of ADHD in nonclinical, nationally representative samples.
Fame: Girls gone wild: fame and vfame

Fame gone wild The things I do in the name of research. It is an idea breathtaking in its brilliance and stunning in its simplicity; if only I had thought of it when I was a teenager. The person who actually thought it up was someone called Joseph R. Francis, currently facing federal prison on tax evasion charges, which goes to show just how much a good idea can screw up your life if it's followed by a not so good idea. The essence of Francis's good idea is this: you ask girls to take their clothes off. Here's the surprising part: they do. Girls Gone Wild is an extraordinarily successful series of short films. The title effectively captures the oeuvre. The films feature teenage or twenty-something girls going wild in various, broadly sexual, ways, including exposing breasts and/or buttocks to the camera with additional fondling of said breasts or buttocks if deemed necessary. In hindsight, perhaps my office wasn't the best place to be conducting this research; various quizzical eyebrows have been raised by the odd student who shows up unannounced at my office to ask questions about this or that essay. Leave me alone: can't you see I'm working? Anyway, my hands are tied. There's no way that Mrs Rowlands is going to let me watch this at home.
Exploring Mathematical Reasoning of the Order of Operations: Rearranging the Procedural Component PEMDAS

PEMDAS is a mnemonic device to memorize the order in which to calculate an expression that contains more than one operation. However, students frequently make calculation errors with expressions, which have either multiplication and division or addition and subtraction next to each other. This article explores the mathematical reasoning of the Order of Operations and the effectiveness of a new approach.
A Preliminary Model of Driver Acceleration Behavior Prior to Real-World Straight Crossing Path Intersection Crashes Using EDRs

There are approximately 4,500 traffic fatalities at intersections each year in the U.S. One method for reducing these crashes is through equipping vehicles with Intersection Advanced Driver Assistance Systems (I-ADAS) that can detect and alert the driver of an impending crash. However, the effectiveness of these systems is expected to be highly dependent on the pre-crash acceleration behavior of drivers prior to these crashes. The first objective of this study was to use pre-crash acceleration data downloaded from Event Data Recorders (EDRs) to evaluate previously developed acceleration profile models that were based off of "typical" acceleration data. Our second objective was to develop a novel acceleration profile model using this pre-crash data. This study used EDR-recorded pre-crash speeds from 89 intersection crashes investigated as part of National Automotive Sampling System / Crashworthiness Data System (NASS/CDS). A 10-fold cross-validation procedure was implemented to generate and evaluate a quadratic-decreasing acceleration profile model developed from this pre-crash data. Our results indicate that previously generated models underestimate pre-crash acceleration behavior of vehicles involved in intersection crashes. An improved, nationally-representative acceleration profile is also presented that should be considered by researchers interested in simulating pre-intersection crash acceleration behavior. These findings have important implications for I-ADAS designers and government regulatory agencies developing and evaluating the algorithm for delivering an effective, reliable alert to the driver.
Towards a Complete Bibliography of V. M. Zhivov

Составление полной библиографии научных работ В.М. Живова – это масштабное предприятие, которое, несомненно, потребует совместных усилий библиотекарей и ученых, представляющих множество различных стран и академических дисциплин. Библиография, помещаемая ниже, призвана лишь представить некоторые дополнения и исправления к “Списку научных трудов Виктора Марковича Живова,” опубликованному в Веренице литер и довести этот список с 2006 года до настоящего времени. Включение дополнительных публикаций — как перепечаток и переводов, так и оригинальных научных работ — будет полезно для будущих исследователей, особенно интересующихся направлением развития идей Живова, их влиянием и каналами их распространения. По той же причине, настоящая библиография также включает ссылки на интервью и публичные лекции Живова и его выступления на радио и телевидении, в том числе те, которые в настоящее время доступны только в Интернете. Хотя включение таких работ, как правило, размывает традиционные границы между академическими и научно-популярными публикациями, оно иллюстрирует характер современного информационного ландшафта и позволяет документировать деятельность Живова как публичного интеллектуала. Библиография, не учитывающая эти аспекты, не может претендовать на полное и достоверное отражение трудов и дней Виктора Марковича Живова.
Classification and characterization of the rice α-amylase multigene family

To establish the size and organization of the rice α-amylase multigene family, we have isolated 30 α-amylase clones from three independent genomic libraries. Partial characterization of these clones indicates that they fall into 5 hybridization groups containing a total of 10 genes. Two clones belonging to the Group 3 hybridization class have more than one gene per cloned fragment. The nucleotide sequence of one clone from Group 1, λOSg2, was determined and compared to other known cereal α-amylase sequences revealing that λOSg2 is the genomic analog of the rice cDNA clone, pOS103. The rice α-amylase genes in Group 1 are analogous to the α-Amy1 genes in barley and wheat. λOSg2 contains sequence motifs common to most actively transcribed genes in plants. Two consensus sequences, TAACA G A A and TATCCAT, were found in the 5′ flanking regions of α-amylase genes of rice, barley and wheat. The former sequence may be specific to α-amylase gene while the latter sequence may be related to a ‘CATC’ box found in many plant genes. Another sequence called the pyrimidine box ( T C CTTTT T C ) was found in the α-amylase genes as well as other genes regulated by gibberellic acid (GA). Comparisons based on amino acid sequence alignment revealed that the multigene families in rice, barley and wheat shared a common ancestor which contained three introns. Some of the descendants of the progenitor α-amylase gene appear to have lost the middle intron while others maintain all three introns.
Rethinking Transcription Coupled DNA Repair

Nucleotide excision repair (NER) is an evolutionarily conserved, multistep process that can detect a wide variety of DNA lesions. Transcription coupled repair (TCR) is a subpathway of NER that repairs the transcribed DNA strand faster than the rest of the genome. RNA polymerase (RNAP) stalled at DNA lesions mediates the recruitment of NER enzymes to the damage site. In this review we focus on a newly identified bacterial TCR pathway in which the NER enzyme UvrD, in conjunction with NusA, plays a major role in initiating the repair process. We discuss the tradeoff between the new and conventional models of TCR, how and when each pathway operates to repair DNA damage, and the necessity of pervasive transcription in maintaining genome integrity.
Clustering of U.S. women receiving no prenatal care: differences in pregnancy outcomes and implications for targeting interventions.

Objectives: Prenatal care is an established mechanism for identifying and managing risk factors impacting pregnancy outcomes. Despite aggressive efforts in the United States (US) to assure that all women begin care in the first trimester, every year about 70,000 women in the US receive no care prior to delivery. We hypothesized that US women receiving no prenatal care comprise clusters (subgroups) with distinctive behavioral, socio-demographic, and medical risks and that birth outcomes differ among the clusters. Methods: White, Black, and Hispanic women (n = 126,220) receiving no prenatal care and delivering a live, singleton infant were identified from linked birth and death certificates for years 1995 through 1997. Cluster analysis was used to group women with similar characteristics, and cluster assignment was evaluated using discriminant analysis. Birth outcomes for any care and no-care women were then examined using logistic regression. Results: Six replicable clusters of women with no care were identified. Birth outcomes varied significantly among clusters and were two to four times worse for no-care clusters compared to outcomes for women receiving any care. Conclusions: Cluster analysis is an effective alternative for grouping individuals for use in public health education, intervention, and outreach programming. Women receiving no prenatal care were characteristically different from women receiving any care in this study, but they did not represent a homogenous group. Findings suggest that interventions should target reducing the proportion of women receiving no care and should be tailored to specific no-care clusters.
Political Polarization as a Constraint on Corruption: A Cross-National Comparison

Summary Efforts to explain corruption have increased dramatically in recent years. The interest stems from the increasing weight economists assign to corruption when explaining economic growth. A great deal of the research focuses on how political institutions influence perceptions of corruption. We move this debate in a new direction by addressing a previously ignored dimension: ideological polarization. We contend perceptions of corruption are determined not only by specific institutional features of the political system—such as elements of voting systems, ballot structures, or separation of powers—but by who sits at the controls. We employ panel data from a broad variety of countries to test our theoretical argument. Contrary to recent findings by both economists and political scientists, we show that ideological polarization predicts perceptions of corruption.
A MapReduce algorithm to create contiguity weights for spatial analysis of big data

Spatial analysis of Big data is a key component of Cyber-GIS. However, how to utilize existing cyberinfrastructure (e.g. large computing clusters) to perform parallel and distributed spatial analysis on Big data remains a huge challenge. Problems such as efficient spatial weights creation, spatial statistics and spatial regression of Big data still need investigation. In this research, we propose a MapReduce algorithm for creating contiguity-based spatial weights. This algorithm provides the ability to create spatial weights from very large spatial datasets efficiently by using computing resources that are organized in the Hadoop framework. It works in the paradigm of MapReduce: mappers are distributed in computing clusters to find contiguous neighbors in parallel, then reducers collect the results and generate the weights matrix. To test the performance of this algorithm, we design experiment to create contiguity-based weights matrix from artificial spatial data with up to 190 million polygons using Amazon's Hadoop framework called Elastic MapReduce. The experiment demonstrates the scalability of this parallel algorithm which utilizes large computing clusters to solve the problem of creating contiguity weights on Big data.
Effect of Smoking on Depressive Symptomatology: A Reexamination of Data from the National Longitudinal Study of Adolescent Health

Using 1995–1996 data from the first two waves of the National Longitudinal Adolescent Health Study, the authors found that respondents who smoked cigarettes scored, on average, three points higher than did nonsmokers on the Center for Epidemiologic Studies Depression (CES-D) Scale. This gap persists even after accounting for observable factors, such as personal and parental characteristics. In contrast, controlling for the influence of unobservable factors potentially correlated with smoking behavior and depression produces smaller estimates. For instance, estimates from a linear regression model augmented with fixed effects suggest that the average male smoker would score 0.84 points higher on the CES-D Scale (95% confidence interval: 0.44, 1.25) than his nonsmoking counterpart; the average female smoker is predicted to score 1.25 points higher on the CES-D Scale (95% confidence interval: 0.75, 1.75) than her nonsmoking counterpart. The authors conclude that, for the average adolescent, the association between smoking and the symptoms of depression can in large part be attributed to the influence of unobservable factors. adolescent; depression; health; smoking
Use of cryoprotectants in combination with immiscible oils for flash cooling macromolecular crystals

Two standard methods have generally been used to prevent destructive ice formation when flash cooling macromolecular crystals for cryocrystallography: (i) permeating the crystal lattice with a cryoprotectant, or (ii) replacing the external liquid around the crystal with an immiscible oil. In two cases where both of the standard methods failed, we obtained satisfactory results with a two-step procedure that combined the use of immiscible oil with diffusable cryoprotectant. The procedure enabled substantially lower concentrations of cryoprotectant to be used. Since many macromolecular crystals are susceptible to high concentrations of cryoprotectant and successful flash cooling is often a trade-off between damage from ice formation and damage from cryoprotectant, this combinatory procedure may find general application.
The formation number of vortex rings formed in uniform background co-flow

The formation of vortex rings generated by an impulsively started jet in the presence of uniform background co-flow is studied experimentally to extend previous results. A piston–cylinder mechanism is used to generate the vortex rings and the co-flow is supplied through a transparent shroud surrounding the cylinder. Digital particle image velocimetry (DPIV) is used to measure the development of the ring vorticity and its eventual pinch off from the generating jet for ratios of the co-flow to jet velocity ($R_{v})$ in the range 0 – 0.85. The formation time scale for the ring to obtain maximal circulation and pinch off from the generating jet, called the formation number ($F$), is determined as a function of $R_{v}$ using DPIV measurements of circulation and a generalized definition of dimensionless discharge time or ‘formation time’. Both simultaneous initiation and delayed initiation of co-flow are considered. In all cases, a sharp drop in $F$ (taking place over a range of 0.1 in $R_{v}$) is centred around a critical velocity ratio ($R_{crit}$). As the initiation of co-flow was delayed, the magnitude of the drop in $F$ and the value of $R_{crit}$ decreased. A kinematic model based on the relative velocities of the forming ring and jet shear layer is formulated and correctly predicts vortex ring pinch off for $R_{v} \,{>}\, R_{crit}$. The results of the model indicate the reduction in $F$ at large $R_{v}$ is directly related to the increased convective velocity provided to the ring by the co-flow.
Expression of a polycistronic messenger RNA involved in antibiotic production in an rnc mutant of Streptomyces coelicolor

RNase III is a double strand specific endoribonuclease that is involved in the regulation of gene expression in bacteria. In Streptomyces coelicolor, an RNase III (rnc) null mutant manifests decreased ability to synthesize antibiotics, suggesting that RNase III globally regulates antibiotic production in that species. As RNase III is involved in the processing of ribosomal RNAs in S. coelicolor and other bacteria, an alternative explanation for the effects of the rnc mutation on antibiotic production would involve the formation of defective ribosomes in the absence of RNase III. Those ribosomes might be unable to translate the long polycistronic messenger RNAs known to be produced by operons containing genes for antibiotic production. To examine this possibility, we have constructed a reporter plasmid whose insert encodes an operon derived from the actinorhodin cluster of S. coelicolor. We show that an rnc null mutant of S. coelicolor is capable of translating the polycistronic message transcribed from the operon. We show further that RNA species with the mobilities expected for mature 16S and 23S ribosomal RNAs are produced in the rnc mutant even though the mutant contains higher levels of the 30S rRNA precursor than the wild-type strain.
Surface-mediated retention effects of subtilisin site-specific variatns in cation-exchange chromatography

Abstract Wild-type subtilisin and several site-specific variants were resolved on a strong cation-exchange column by isocratic elution and a series of sodium chloride concentrations. Changes in primary sequence at the protein surface have an observable effect on the chromatographic behavior of subtilisin. This supports the concept that three-dimensional structure determines which biopolymer surface residues are in position to interact with the stationary phase surface. The retention data fit the stoichiometric displacement model (SDM) of retention. Plots of ln k′ vs. ln 1/[NaCl] yield values for the average number of ionic groups (Z) on the protein that interact with the support matrix. Application of the SDM to the chromatographic retention of the variants has uncovered an unusual phenomenon at the protein surface at low ionic strength. A SDM plot normally provides a linear relationship between ln k ′ and l/[NaCl] with the slope corresponding to the Z number. This study revealed two lines differing in slope and intercept, indicating that the Z number of subtilisin changes at some intermediate ionic strength of the eluent. These results are attributed to some salt-induced protein surface event that triggers a change in structure. Chromatographic detection of this occurrence reflects the connection between the surface-mediated event and mobile phase ionic strength.
Determination of radiophosphorus by solvent-extraction

Abstract A procedure is given for the determination of radiophosphorus in the presence of other activities. Potassium phosphate is added as carrier and the phosphorus is extracted as phospho-molybdic acid into a butanol-chloroform mixture. The activity is back-extracted into ammonium hydroxide and the phosphate is precipitated as magnesium ammonium phosphate. This may be air-dried or ignited to magnesium pyrophosphate for counting. The method is rapid, accurate, and free from interference by other radionuclides. Especially noteworthy is the excellent separation from radioarsenic.