cssi/SciSciGPT-SciSciNet huggingface dataset:
The Mutagenicity of Chemical Carcinogens: Correlations, Problems, and Interpretations

Mutagenesis and carcinogenesis are complex cellular processes which are grossly similar in that each produces heritable changes in phenotype. Experimental mutagenesis by a pure chemical agent was first achieved by Auerbach and Robson (1944, 1946) and a variety of such agents are now known. Their mechanisms of action appear to be fairly well understood as consisting of expressible heritable changes in the molecular structure of the genetic material or DNA (Orgel, 1965; Freese and Freese, 1966; Auerbach, 1967; Freese, this book). Carcinogenesis by chemical agents was discovered first in humans almost 200 years ago, and today nearly a dozen agents active in the human and of widely varying structure are known (Clayson, 1962; Hueper and Conway, 1964; Miller, J. A., 1970). The experimental induction of cancer with a pure chemical compound was first achieved about 1930, and many chemical carcinogens of greatly differing structures are known today (see preceding references). However, it is not known at the molecular level how any chemical carcinogen induces the formation of cells which are not responsive to the growth controls of the host and which form neoplasms that grow more or less continuously and may invade normal tissues. This is also true of the carcinogenic action of viruses and radiation. Likewise, the molecular phenotype of no neoplasm is even partially understood.
Short-Term Perioperative Complications and Mortality After Total Ankle Arthroplasty in the United States.

This study sought to identify patient and operative demographics associated with 30-day perioperative complications in patients undergoing total ankle arthroplasty as recorded in the National Surgical Quality Improvement Project database. Complications were divided into local and systemic and further subcategorized as major and minor. A total of 404 patients underwent total ankle arthroplasty between 2007 and 2014 as captured in the National Surgical Quality Improvement Project database. The overall complication rate was 2.4% with 0.5% mortality and 0.2% infection rate. Length of hospital stay, both as an end point at >5 days and as a continuous variable, was associated with overall complications (odds ratio [OR] = 9.90, P = .002 and OR = 1.52, P = .006, respectively). Patient characteristics that predicted perioperative morbidity included presence of 3 or comorbidities (OR = 8.48, P = 0.038), American Society of Anesthesiologists class III, and history of previous cardiac surgery (OR = 12.22, P = .033). ...
Insect Bioelectronics: A Theoretical and Experimental Study of Insect Spines as Dielectric Tubular Waveguides

Abstract A new concept of the insect communication system is based on the electrical characteristics of the insect exoskeleton and the configuration of the various spines and sensillae that protrude from the insect exoskeleton. The morphology and electrical characteristics of the spines and sensillae on the insect antennae indicate that they are tubular dielectric waveguides acting as aerials for the detection of certain light and IR frequencies. In order to test these theories, various infrared and visible radiations are being utilized and the insect subjected to wavelengths in the visible, near (NIR), intermediate (IIR), and far infrared (FIR) regions. Photographs of moths in full flight demonstrate that the moth antennae has considerable stability in flight. The formulas for determining the resonant modes of dielectric aerials were applied to the dimensions of the antennal spines of the night-flying moths. The results invariably calculated out in the visible:, infrared, or microwave region. The insect exoskeleton is covered with a waxy layer which has inherently the characteristics known to physicists as thermoelectret properties. Beeswax is one of the most efficient thermoelectrets. The insect exoskeleton has a dielectric constant between 2 and 3, the dielectric constant most expected for an efficient waveguide design in the visible and infrared region. For hollow dielectric waveguides with a refractive index of n-1.5, where n=√⌂ so that ⌂=2.25, the Hivjj mode exhibits the lowest attenuation. The refractive index of the insect exoskeleton is 1.5. The dielectric constant has been measured in the millimeter region as lying between 2.5 and 3.0. The directivity of the dielectric aerial of optimum design is proportional to tubelength. Such an aerial has a single lobe radiation pattern if the wall thickness is small, as in the case of insects, and of such a value that only the HE11, or hybrid, mode is excited. The main lobe of the radiation pattern of the dielectric rod, or tube, is more directive and the side lobes are smaller if the rod is tapered toward the free end. The dielectric taper formulas fit the insect spines and most insect spines are tapered. Then the dielectric spines on the scape and pedicel of 2 species of saturnid moths were irradiated with visible coherent (6328 A) and incoherent radiation, sensors responded to the light by sending a biphasic pulse down the entire length of the central antennal nerve. The biphasic nerve potential apparently apparently gates the antennae and prevents the moths from responding to environmental signals during the day.
Cellular eyelashes help striatal neurons hook up

Primary cilia-based signaling provides critical infrastructure for formation of striatal neuronal networks.
A novel nomogram for the treatment of astigmatism with femtosecond-laser arcuate incisions at the time of cataract surgery.

PURPOSE The purpose of this study was to determine an arcuate incision (AI) nomogram to treat astigmatism during femtosecond laser-assisted cataract surgery. METHODS This is a retrospective, cohort study. Femtosecond laser (FSL)-assisted transepithelial AIs were created at a 9.0 mm optical zone, 80% depth, centered on the limbus. We modified the manual Donnenfeld limbal relaxing incision nomogram to 70% for with-the-rule (WTR), 80% for oblique (OBL), and 100% for against-the-rule (ATR) astigmatism. The correction index (CI) equaled AI-induced astigmatism/target-induced astigmatism. Measures included preoperative keratometric corneal cylinder (Pre Kcyl), postoperative Kcyl (Post Kcyl), and postoperative residual refractive astigmatism (Post RRA). RESULTS Mean Pre Kcyl and 1-2 months Post RRA in 161 eyes of 116 patients were 0.626±0.417 diopters (D) (range 0.5-2 D), and 0.495±0.400 D (range 0-1.5 D), respectively. Mean absolute astigmatic changes (Pre Kcyl-Post Kcyl) without accounting for axis change in the WTR, ATR, and OBL groups were 0.165±0.383 D (P<0.001), 0.374±0.536 D (P<0.001), and 0.253±0.416 D (P=0.02), respectively. Mean absolute astigmatic changes using RRA as the postoperative measurement (Pre Kcyl-Post RRA) without accounting for axis change were 0.440±0.461 D (P<0.001), 0.238±0.571 D (P<0.05), 0.154±0.450 (P=0.111) in WTR, ATR, and OBL groups, respectively. CIs for WTR, ATR, and OBL were 0.53, 1.01, and 0.95, respectively. There were no intraoperative or postoperative complications related to the AIs. CONCLUSION Transepithelial FSL-AIs using the modified Donnenfeld nomogram show potential for management of mild to moderate corneal astigmatism. An increase in the magnitude or reduction of the optical zone size for the treatment of WTR and ATR astigmatism for this nomogram may further improve refractive accuracy.
Abstract 16041: Interaction of Genetic Variation at the ABO Locus With Short-Term Exposure to Elevated Fine Particulate Matter Air Pollution Results in Differential Associations With Acute Coronary Events

Introduction: Fine particulate matter (PM2.5) air pollution is associated with risk of acute coronary syndrome (ACS) events primarily in patients with coronary artery disease (CAD). ABO gene sequen...
Lab-scale observations of flame attachment on slopes with implications for firefighter safety zones

Abstract The Coanda effect is the phenomenon in which a jet entering quiescent fluid attaches to a nearby solid object due to inhibited entrainment of ambient fluid near the solid. Little is known about the influence of the Coanda effect on wildland fire behavior. Specifically, there is a lack of knowledge regarding how the flame attachment on slopes influences firefighter safety zone considerations in rugged terrain. This paper presents results for small-scale n-heptane pool fire experiments near a slope, showing how flame shape and heat flux are influenced by slope angle, slope boundary condition and distance from flame base. Flames near slopes leaned toward the slope, and at some slope angles the flames attached to the slope. The average angle at which the effects of slope were noticeable was between 10° and 45°, depending on the criteria used. No difference was observed between a bare slope and an insulated slope. Dimensional analysis showed that important characteristics of flame attachment on slopes in the small-scale experiments were in the range estimated for the large fires. The implication is that the traditional view of safe separation distance as being the distance from the flame base is inadequate for fires near slopes.
Sex differences, duration of stay in the United States, and serious psychological distress: the case of Middle Eastern Immigrants in the United States

Using data from the 2002-2012 National Health Interview Surveys, this study examines the association between duration of stay in the United States and serious psychological distress (SPD) among Middle Eastern (ME) immigrants and tests whether this association differs by sex. Results show that although ME immigrant women with longer duration are significantly more likely to report SPD than US-born white women, the SPD of ME immigrant men do not significantly differ from that of US-born white men. These findings emphasize the harmful influence of a longer duration of stay in the United States on the SPD of ME immigrant women.
Physics and applications of counter propagating solitons in microcavities (Conference Presentation)

Microresonator solitons orbit around a closed waveguide path and produce a repetitive output pulse stream at a rate set by the roundtrip time. Here, counter-propagating solitons that simultaneously orbit in an opposing sense (clockwise/counter-clockwise) are studied. Despite sharing the same spatial mode family, their roundtrip times can be precisely and independently controlled. Furthermore, a state is possible in which their relative optical phase and repetition rates are locked. This state allows a single resonator to produce dual-soliton frequency-comb streams with different repetition rates, but with a high relative coherence that is useful in spectroscopy and ranging.
Predictors of Prolonged Operative Time for Robotic-Assisted Laparoscopic Myomectomy: Development of a Preoperative Calculator for Total Operative Time.

ABSTRACT Study Objective To develop a preoperative calculator to predict the total operative time (TOT) for robotic-assisted laparoscopic myomectomy (RALM). Design Retrospective cross-sectional study. Setting University medical center. Patients Women who underwent RALM performed by 3 high-volume surgeons at a single institution between January 2014 and December 2017. Interventions Demographic characteristics, indication for surgery, surgical history, myoma burden on imaging, and TOT were collected. RALM operative time was classified as 5 hours. We identified preoperative characteristics predictive of increased operative time and developed a preoperative calculator to estimate TOT. Measurements and Main Results A total of 126 women underwent RALM during the study period, with a mean TOT of 213 minutes ± 66 minutes. The mean total weight of myomas removed was 264 g ± 236 g, and mean largest myoma diameter was 8.5 cm ± 2.6 cm. Overall, mean number of myomas removed was 2.5 ± 2.4, and estimated blood loss (EBL) was 215 ± 212 mL. Five patients (4.0%) received a blood transfusion, and 4 patients (3.2%) underwent conversion to laparotomy. Preoperative factors significantly associated with TOT included patient age, personal history of diabetes mellitus, uterine volume, number of myomas, number of myomas >3 cm, diameter of the dominant myoma, and surgeon experience. The mean uterine volume was 282 cm3 for procedures with a TOT 5 hours (p = .004). Body mass index, personal history of hypertension, previous abdominal/pelvic surgery, surgical indication, location of dominant myoma (anterior, posterior, or fundal) and classification of dominant myoma (submucosal, intramural, subserosal, or other) were not associated with TOT. Our preoperative calculator correctly predicted TOT category in 88% of the patients and estimated TOT within a 1-hour margin in 80% of patients. Conclusion RALM is becoming a more popular surgical approach for the management of uterine myomas. Preoperative radiographic evaluation and a thorough patient history may enhance patient counseling and surgical planning. Uterine volume and myoma number and size appear to be more predictive of TOT compared with myoma location.
Positive Surgical Margins in Submandibular Malignancies: Facility and Practice Variation.

ObjectivesIdentify positive margin rate in a national cohort of patients with submandibular carcinoma, identify predictors of positive margins, and associate margins with overall survival.Study Des...
Forensic Searches of Electronic Devices at the Border: United States v. Touset

In United States v. Touset,1 the Eleventh Circuit held that the Fourth Amendment does not require reasonable suspicion for a forensic search of an electronic device at the border, creating a circui...
Analysis of Student Behavior Using the R Package crsra

Due to the fundamental differences between traditional education and Massive Open Online Courses (MOOCs) and the ever-increasing popularity of MOOCs more research is needed to understand current and future trends in education. Although research in the field has rapidly grown in recent years, one of the main challenges facing researchers remains to be the complexity and messiness of the data. Therefore, it is imperative to provide tools that pave the way for more research on the new subject of MOOCs. This paper introduces a package called crsra based on the statistical software R to help tidy and perform preliminary analysis on massive loads of data provided by Coursera. The advantages of the package are as follows: a) faster loading and organizing data for analysis, b) an efficient method for combining data from multiple courses and even across institutions, and c) provision of a set of functions for analyzing student behaviors.
Haptics for Sensory Substitution

Using one sensory modality to compensate for a modality that is unavailable is called Sensory Substitution and it is useful and often necessary for conveying some types of information effectively to people with disabilities. Using haptics to substitute for other modalities provides unique benefits as the tactile modality is incredibly flexible and underutilized. This chapter explores general purpose, media-focused, and interactive applications of Haptic Sensory Substitution as well as the future of Haptic Sensory Substitution and its implications for assistive technology.
Benchmarking the value of care: Variability in hospital costs for common operations and its association with procedure volume.

Background Efforts to improve health care value (quality/cost) have become a priority in the United States. Although many seek to increase quality by reducing variability in adverse outcomes, less is known about variability in costs. In conjunction with the American Association for the Surgery of Trauma Healthcare Economics Committee, the objective of this study was to examine the extent of variability in total hospital costs for two common procedures: laparoscopic appendectomy (LA) and laparoscopic cholecystectomy (LC). Methods Nationally weighted data for adults 18 years and older was obtained for patients undergoing each operation in the 2014 and 2016 National Inpatient Sample. Data were aggregated at the hospital-level to attain hospital-specific median index hospital costs in 2019 US dollars and corresponding annual procedure volumes. Cost variation was assessed using caterpillar plots and risk-standardized observed/expected cost ratios. Correlation analysis, variance decomposition, and regression analysis explored costs' association with volume. Results In 2016, 1,563 hospitals representing 86,170 LA and 2,276 hospitals representing 230,120 LC met the inclusion criteria. In 2014, the numbers were similar (1,602 and 2,259 hospitals). Compared with a mean of US $10,202, LA median costs ranged from US $2,850 to US $33,381. Laparoscopic cholecystectomy median costs ranged from US $4,406 to US $40,585 with a mean of US $12,567. Differences in cost strongly associated with procedure volume. Volume accounted for 9.9% (LA) and 12.4% (LC) of variation between hospitals, after controlling for the influence of other hospital (8.2% and 5.0%) and patient (6.3% and 3.7%) characteristics and in-hospital complications (0.8% and 0.4%). Counterfactual modeling suggests that were all hospitals to have performed at or below their expected median cost, one would see a national cost savings of greater than US $301.9 million per year (95% confidence interval, US $280.6-325.5 million). Conclusion Marked variability of median hospital costs for common operations exists. Differences remained consistent across changing coding structures and database years and were strongly associated with volume. Taken together, the findings suggest room for improvement in emergency general surgery and a need to address large discrepancies in an often-overlooked aspect of value. Level of evidence Epidemiological, level III.
A NOVEL ECHOCARDIOGRAPHIC INDEX DEMONSTRATING REDUCED RELATIVE VALVE LOAD IN PATIENTS WITH PARADOXICAL LOW-FLOW COMPARED TO NORMAL-FLOW SEVERE AORTIC STENOSIS WITH PRESERVED LEFT VENTRICULAR EJECTION FRACTION

Paradoxical low-flow severe aortic stenosis (LF AS) despite preserved left ventricular ejection fraction (LVEF) has been shown to be distinct from normal-flow (NF) AS, with poorer prognosis. Relative valve load (RVL) is an echocardiographic index which has been used to estimate the relative
‘Ou ni right-la pou remain silans’: The case for a standard Kwéyòl translation of the pre-trial right to silence

Abstract Although in recent years researchers have intensified focus on the communication of the pre-trial right to silence or police caution to native and non-native speakers of English, most of this research has been concerned with linguistic complexity, comprehension, and comprehensibility issues. Relatively few studies have focused attention on the role played by the deliverer of the caution in the communicative equation (Cotterill 2000), particularly in situations where the caution has to be interpreted or translated by its deliverer. Drawing on a sociolinguistic variation approach, this study investigates the communication of the police caution to creole speakers, who remain nearly invisible in the research to date. It uses the categories of literal and free translation as tools to analyze spontaneous translations of the caution from English to French lexicon Creole (Kweyol) produced by (n = 25) police officers in St. Lucia. The results show considerable variability in these translations, which may have negative consequences for the accused. This study seeks to draw attention to these consequences, by underscoring some of the inaccuracies that may occur in translating or interpreting a caution written in English to Kweyol, and make a case for policy that would use the language of the accused in situations of language variation. The study argues that such a policy, which standardizes the Kweyol version of the caution, would not only obviate the potential for variability, but would also minimize misunderstandings, which could compromise the legal rights of the suspect.
Z 2 phases and Majorana spectroscopy in paired Bose-Hubbard chains

We investigate the Bose-Hubbard chain in the presence of nearest-neighbor pairing. The pairing term gives rise to an unusual gapped ${\mathbb{Z}}_{2}$ Ising phase that has number fluctuation but no off-diagonal long range order. This phase has a strongly correlated many-body doubly degenerate ground state which is effectively a gap-protected macroscopic qubit. In the strongly interacting limit, the system can be mapped onto an anisotropic transverse spin chain, which in turn can be mapped to the better-known fermionic sister of the paired Bose-Hubbard chain: the Kitaev chain which hosts zero-energy Majorana bound states. While corresponding phases in the fermionic and bosonic systems have starkly different wave functions, they share identical energy spectra. We describe a possible cold-atom realization of the paired Bose-Hubbard model in a biased zigzag optical lattice with reservoir-induced pairing, opening a possible route towards experimental Kitaev chain spectroscopy.
Granulomatosis with Polyangiitis Masquerading as Pituitary Adenoma with Apoplexy

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is a small- and medium-vessel autoimmune vasculitis. Rare presentations of GPA can manifest as ophthalmologic and endocrinological deficits with sellar enhancement on imaging. While GPA typically presents distinct in appearance from other sellar pathologies, such as pituitary adenoma, we report the case of a 41-year-old woman with GPA of the pituitary that was initially diagnosed as pituitary macroadenoma with apoplexy and treated with two surgical resections without improvement of clinical symptoms. Pathology analysis of the second resection specimen revealed an inflammatory process consistent with GPA. After the pathologic and clinical diagnosis of GPA was established, treatment with steroid and steroid-sparing immunosuppressants resulted in improvements both on imaging and symptomatically. We discuss important aspects of the diagnosis and treatment of this rare presentation of GPA.
The Effect of Property Reassessments on Fiscal Transparency and Government Growth: Evidence from Virginia

An important concern to the efficiency of public finance systems is that voters suffer from various "fiscal illusions" that can politicians can exploit to expand the public sector. This paper contributes evidence of this effect on a public finance system through the revenue elasticity hypothesis, which is a form of fiscal illusion in which voters confuse tax rates with tax burdens in the approval of public spending. The applied empirical setting is Virginia cities and counties from 2001 to 2011, where the timing of mass property reappraisals is exogenous but known to local policymakers in setting the annual budget. The results indicate that mass reappraisals, which reduce tax rates, do cause property tax increases, as do reappraisals that will result in future tax rate increases. These revenue shocks are then smoothed into expenditures through the management of assets, indicating that policymakers prefer the spending to be drawn from future cash reserves rather than from immediate projects that might draw attention to the source of fiscal illusion.
Laterally transferred macrophage mitochondria acts as a signaling source promoting cancer cell proliferation

Abstract Lateral transfer of mitochondria occurs in many physiological and pathological conditions. Given that mitochondria provide essential energy for cellular activities, mitochondrial transfer is currently thought to promote the rescue of damaged cells. We report that mitochondrial transfer occurs between macrophages and breast cancer cells, leading to increased cancer cell proliferation. Unexpectedly, transferred macrophage mitochondria are dysfunctional, lacking mitochondrial membrane potential. Rather than performing essential mitochondrial activities, transferred mitochondria accumulate reactive oxygen species which activates ERK signaling, indicating that transferred mitochondria act as a signaling source that promotes cancer cell proliferation. We also demonstrate that pro-tumorigenic M2-like macrophages exhibit increased mitochondrial transfer to cancer cells. Collectively, our findings reveal how mitochondrial transfer is regulated and leads to sustained functional changes in recipient cells. One-Sentence Summary Lateral transfer of macrophage mitochondria acts as a ROS signaling source, regulating cancer cell proliferation through ERK signaling.
Prehospital Lactate is Associated with the Need for Blood in Trauma.

Background: Traumatic hemorrhage is the leading cause of preventable death, and its effects are often evident within the first 24 hours of hospital admission. We investigated the relationship between prehospital lactate measurement and administration of hospital blood products and life-saving interventions (LSIs) within 24 hours of hospital admission.Methods: We included trauma patients with recorded prehospital venous lactate transported by a single critical care transport service to a Level I trauma center between 2012 and 2019. We abstracted vital signs, mission type, anatomic location of injury, prehospital administration of crystalloid and blood products, and hospital LSIs started within 24 hours of admission. We used logistic regression to determine the association of prehospital lactate and in-hospital administration of blood products in groups with or without hypotensive patients. We investigated the effect of prehospital lactate concentration on secondary outcomes such as LSIs and mortality.Results: We included 2,170 patients transported from the scene or emergency department (ED), of whom 1,821 (84%) were normotensive. The median concentration of prehospital lactate was 2.10 mmol/L for the main population (IQR = 1.40-3.30) and 2.00 mmol/L for the normotensive subgroup (IQR = 1.30-2.90). A higher prehospital lactate concentration was associated with higher odds of needing early hospital blood products in the whole study population (OR = 1.12, (95% CI 1.06-1.20), p < 0.01) and in the normotensive subgroup (OR = 1.13, (95% CI 1.03-1.22), p = 0.01). These positive associations were also observed with the secondary outcome of hospital LSIs, and higher prehospital lactate was also associated with higher odds of mortality (OR = 1.32, (95% CI 1.20-1.45), p < 0.01).Conclusions: Higher concentrations of prehospital lactate were associated with the need for in-hospital blood transfusion within 24 hours of admission. The relationship between lactate and blood transfusion persisted among normotensive patients. Further work is needed to incorporate prehospital lactate into decision support tools for prehospital blood administration.
Más allá del transnacionalismo: Una perspectiva alternativa de la conexión de los inmigrantes con su país de origen

La literatura sobre transnacionalismo ha demostrado que las migraciones internacionales inevitablemente generan conexiones transfronterizas. Sin embargo, esta perspectiva oculta las formas en las que los lazos que unen a los Estados emisores y receptores tambien se tensan con los procesos mediante los cuales los Estados-nacion se mantienen apartados del mundo. Este trabajo busca identificar los mecanismos que generan y asi mismo atenuan los vinculos interestatales de una serie de actividades, resumiendo los resultados de las investigaciones sobre las relaciones sociales transfronterizas, la politica hacia los emigrantes, las respuestas de los Estados de emigracion, y la participacion del pais de origen en la segunda generacion. Beyond Transnationalism: An Alternative Perspective on Immigrants’ Link with their Country of Origin Abstract The literature on transnationalism has shown that international migrations inevitably generate cross-border connections. However, that perspective also obscures the ways in which the ties linking sending and receiving states also come into tension with the processes by which nation-states keep themselves apart from the world. This essay seeks to identify the mechanisms that both generate and attenuate cross-state ties across a range of activities, synthesizing the results of research on cross-border social ties, emigrant politics, emigration state responses, and home country engagement among the second generation.
Rate of ablation with depolymerization

The rate of ablation is calculated for the case of combined erosion and volatilization due to depolymerization. The parameters of the medium are separated from the properties of the polymer and combined in two complexes whose influence is illustrated by means of nomograms for polymethyl methacrylate. The conclusions are confirmed by the results of tests employing a hypersonic rarefied argon plasma jet.
Diet and oxidative stress: a novel synthesis of epidemiological data on Alzheimer's disease.

In an innovative synthesis, William B. Grant links Alzheimers disease to diet by combining the prevalence of Alzheimers disease in several countries with a meta-analysis of communitybased studies of diet (3). A positive relationship between caloric, as well as fat, intake and the prevalence of Alzheimers disease is demonstrated. These findings link Alzheimers disease to diet in a more general sense than previous studies that focused instead on specific dietary components such as consumption of brain, raw meat, seafood, alcohol, coffee or vitamin supplements. These latter studies usually had the single goal of determining whether food-borne pathogens or toxins might be implicated, rather than focusing on foods as a source of nutrients. Numerous animal studies show prolonged maximum life span and health benefits with caloric restriction (reviewed in (2)), nonetheless, it is perhaps surprising that a multifactorial disease such as Alzheimers disease appears to be so responsive to total caloric or fat intake (r ~ 0.9). While it can be argued that the caloric content of food over many different ethnic groups
RNA synthesis during bacteriophage SPO1 development: II. Some modulations and prerequisites of the transcription program

Abstract A detailed RNA-DNA hybridization-competition analysis of the program of transcription during bacteriophage SPO1 development has been made. The synthesis of six classes of viral RNA ( e , em , m , m 1 l , m 2 l , and l ) has been distinguished previously ( Gage and Geiduschek, 1971 ). In this paper some of the modulations and pre-requisites of transcription of these classes of viral RNA are analyzed. It is shown that within the class of em transcripts, not all polynucleotide sequences first appear at the same time. A comparable asynchrony of first appearance occurs with e RNA. Between the time of repression of e transcription and the onset of viral DNA replication, em RNA becomes 2.5 times more abundant; this is concomitant with increased viral transcription. In late development, m 1 l , m 2 l , and l RNA are transcribed at constant relative rates, yet m 1 l RNA becomes less abundant during this period, probably because of decreased stability. The role of protein and viral DNA synthesis in the transcription program have also been analyzed. Formation of the viral DNA-host RNA polymerase complex ensures synthesis of e and em RNA, but all subsequent turn-on and shut-off events require some postinfection protein synthesis. In cells infected with a DNA negative mutant, the transcriptional program appears normal except that l RNA is not made. The time of first initiation of RNA chains, whose translation products are essential for two viral functions, has been measured with the use of rifamycin. The two functions in question are the shut-off of host DNA synthesis and the replication of viral DNA. The first initiation of their conjugate sets of messages coincides with the first appearance of m and m 1 l RNA. We conclude that transcription of one or both of these classes of RNA is controlled positively, at RNA chain initiation.
Organizing and accessing a comprehensive knowledge base using the World Wide Web

To address the problem of information overload in today's world, we have developed START, a natural language question answering system that provides users with high-precision information access through the use of natural language annotations. To address the difficulty of accessing large amounts of heterogeneous structured and semistructured data, we have developed Omnibase, which assists START by integrating Web databases into a single, uniformly structured "virtual database." To address the sheer amount of unstructured information available electronically, we have developed techniques for distilling large amounts of free text into relations that capture the salient aspects of the text. The combination of natural language annotation technology, object-property-value data model, and relation extraction technology allows us to rapidly develop and deploy smart applications for knowledge intensive domains. Our ultimate goal is to develop a computer system that acts like a "smart reference librarian," providing users with "just the right information" in response to questions posed in natural language.
Toward Improving the Mathematics Preparation of Elementary Preservice Teachers

Research suggests the importance of mathematics knowledge for teaching (MKT) for enabling elementary school teachers to effectively teach mathematics. MKT involves both mathematical content knowledge (M-CK) and mathematical pedagogical content knowledge (M-PCK). However, there is no consensus on how best to prepare elementary preservice teachers (PSTs) to achieve M-CK and M-PCK. This study builds on research related to MKT by investigating influences of mathematics content courses designed specifically for elementary PSTs (IMPACT courses—Impact of Mathematics Pedagogy and Content on Teaching) on their attitudes (i.e., confidence and motivation) toward M-CK and M-PCK. Results suggest that the PSTs who participated in these IMPACT courses not only acquired high levels of confidence and motivation toward M-CK, but also showed significant and greater gains in attitudes toward M-PCK, after taking the required mathematics methods course, than their counterparts. Further, the findings suggest that these IMPACT courses provided a mathematical foundation that allowed the PSTs to engage in mathematics teaching methods better than those PSTs who did not have such a foundation. These results suggest potential course experiences that may enhance M-CK and M-PCK for elementary PSTs.
Education by Appropriate Analogy

A Kannada proverb of South India states that “The plant in the courtyard is not a medicine,” meaning that what is familiar and close is often overlooked as a valuable resource. This proverb is an appropriate beginning for this paper for what will be discussed is not a new method of education but rather a use of the familiar to explain the new — education by analogy.
Resolution and Limitations in Biological Applications of Atomic Force Microscopy

Atomic force microscopy (AFM) has been applied to image DNA and a membrane protein: cholera toxin. By use of the Kleinschmidt method, DNA molecules were picked up on carbon-coated mica surfaces and imaged by AFM in air and in organic solvents. The resolution was found to be closely related to the adhesion force and a resolution of 3–6 nm was routinely obtained when the adhesion force was below 3 nN. The role of the adhesion force, the tip condition and the specimen preparation on resolution and imaging quality will be discussed. Polymerized diacetylene phosphatidylcholine (DAPC) bilayers provide a relatively stable matrix for studying membrane proteins. When cholera toxin (complete or B-subunit oligomer) was bound to mixed bilayers of DAPC and the receptor glycolipid GM1, the subunit structure was well resolved by AFM in buffer, without crystallization. The resolution was better than 2 nm with excellent reproducibility for a probe force of 0.3–0.5 nN. These results show that individual biomacromolecules under native conditions can be imaged by AFM with high spatial resolution.
Effects of Gaze Shifts on Maintenance of Spatial Memory in Macaque Frontal Eye Field

The activity of 91 neurons in the frontal eye fields (FEFs) of two macaque monkeys was recorded while the animals performed a delayed spatial match-to-sample task. During the delay, the animals were required to shift their gaze to one of four eccentric locations. Neuronal activity during the delay was analyzed for sensitivity to cue location and eye position. One-third of the neurons showed significant delay activity selective for cue location, whereas slightly more than one-half of the neurons showed significant modulation of delay activity when the gaze was shifted to an eccentric location. Despite this modulation, the neurons continued to signal their preferred cue location during most of the delay. However, after recentering saccades, the memory signal was temporarily abolished and then reemerged over a period of few hundred milliseconds. This is consistent with the idea that spatial working memory is buffered outside of the FEF. For most neurons, delay activity tended to increase when the gaze was shifted away from the preferred location and to decrease when the gaze was shifted toward the preferred location. This pattern of modulation is consistent with a vector subtraction mechanism that allows for the superposition of multiple saccade plans.
Position diagnostics for a magnetic-pinch imploding-cylinder x-ray generator

Two diagnostic systems have been developed to assess the position and shape of a cylindrical imploding plasma sheath x-ray source. Both systems employ batteries of inexpensive nitrogen lasers. For measurement of the cylinder radius, eight 75-μJ, 1.2 -ns (FWHM) nitrogen lasers will form a series of narrow beams displaced parallel to the cylinder diameter. As the plasma implodes over a 2-μs period, these position-sampling lasers are fired in sequence at times expected to result in partial shadowing. The 2-cm wide beams strike a position-sensitive detector made up of a helical fiber-optic delay line of 2-mm pitch and 4-ns delay/turn. The clad plastic fiber is doped with Rhodamine B at the points where the 337.1-nm laser beams strike, and the fluorescent red flashes propagate along the optical delay line in both directions to avalanche photodiodes. One signal is displayed on a 5-MHz vertical raster; the other is displayed on four turns of a 2-MHz spiral sweep. The envelopes of both pulse trains are displayed on a conventional dual-beam scope. The nitrogen lasers are aligned axially and displaced radially by a system of mirrors. To assess the symmetry of the implosion, another battery of four nitrogen lasers is used to provide paraxially displaced multiple-image pinhole schlieren pictures.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
MEK inhibitors, novel anti-adhesive molecules, reduce sickle red blood cell adhesion in vitro and in vivo, and vasoocclusion in vivo.

In sickle cell disease, sickle erythrocyte (SSRBC) interacts with endothelial cells, leukocytes, and platelets, and activates coagulation and inflammation, promoting vessel obstruction, which leads to serious life-threatening complications, including acute painful crises and irreversible damage to multiple organs. The mitogen-activated protein kinase, ERK1/2, is abnormally activated in SSRBCs. However, the therapeutic potential of SSRBC ERK1/2 inactivation has never been investigated. I tested four different inhibitors of MEK1/2 (MEK), the kinase that activates ERK1/2, in a model of human SSRBC adhesion to TNFα-activated endothelial cells (ECs). SSRBC MEK inhibition abrogated adhesion to non-activated and TNFα-activated ECs to levels below baseline SSRBC adhesion to non-activated ECs in vitro. SSRBC MEK inhibition also prevented SSRBCs from activating naive neutrophils to adhere to endothelium. To determine the effect of MEK inhibitors on SSRBC adherence in vivo, sham-treated or MEK inhibitor-treated SSRBCs were infused to nude mice previously treated with TNFα. Sham-treated SSRBCs displayed marked adhesion and occlusion of enflamed vessels, both small and large. However, SSRBC treatment with MEK inhibitors ex vivo showed poor SSRBC adhesion to enflamed vessels with no visible vasoocclusion in vivo. In addition, MEK inhibitor treatment of SSRBCs reduced SSRBC organ trapping and increased the number of SSRBCs circulating in bloodstream. Thus, these data suggest that SSRBC ERK1/2 plays potentially a critical role in sickle pathogenesis, and that MEK inhibitors may represent a valuable intervention for acute sickle cell crises.
A model for university enrollment planning

Abstract The expansion to year-round university operation by the addition of a summer term makes enrollment planning both more complex and more critical. Unless the summer term's effects on enrollment levels in the conventional terms are controlled, the potential financial benefits from year-round university operation can be greatly diminished. A mathematical programming model is developed to determine the admissions policies necessary to maintain optimal enrollment levels in all terms in the academic year. The model is used to analyze admission policies for Yale University under conventional (i.e. two-term) operation, and with the proposed summer term.
Plemelj Formulas for Rarita-Schwinger Type Operators

We introduce Plemelj formulas for Rarita-Schwinger operators defined over Lipschitz graphs in \({\mathbb{R}^{n}}\) and their corresponding surfaces on the sphere, Sn and real projective spaces. We introduce the corresponding Hardy p-spaces for \({1 < p < \infty}\). We also introduce Rarita-Schwinger analogues of the classical Szego projection operators and Kerzman-Stein formulas.
Anaplastic thyroid cancer and hyperthyroidism.

We report a rare case of thyrotoxicosis in a patient with anaplastic thyroid cancer. A 65-yr-old male presented with a 2-d history of rapidly enlarging neck mass and back pain. Physical examination revealed a large, hard thyroid mass and resting tachycardia. He did not have any symptoms suggestive of airway compression at presentation. Thyroid hormone levels were consistent with a hyperthyroid state. CT scan of the neck and thorax showed a heterogeneous mass replacing the thyroid, bilateral pulmonary nodules, and a metastasis with pathological fracture at the level of T-8. Technetiumpertechnetate scan failed to show any uptake in the region of the thyroid. Fine needle aspiration of the thyroid revealed anaplastic thyroid cancer. The patient was started on steroids and radiation therapy of his spine lesion. Brief surgical exploration of the thyroid revealed extensive local infiltration of adjacent neck tissues and marked tumor necrosis. Immunohistochemical stains of the tumor were positive for p53, thyroglobulin, and thyroid transcription factor-1. The tumor had an extremely aggressive course and the patient died of asphyxiation from severe airway compromise 11 d after his initial presentation.
Gene territories and cancer.

An analysis of the propinquity of selected gene loci in the nuclei of a particular lymphoblastoid cell line has identified a statistical correlation with their propensity for oncogenic translocations.
Estimating tensile creep data from flexure data

Safety factors are derived for converting bend data to tensile data for creep. It is assumed that the ceramic being stressed is subject to preferential damage in tension. The analysis shows that the safety factors can be relaxed considerably when compression data are available to augment the bend data.
Nucleationless island formation in SiGe/Si(100) heteroepitaxy

The formation of faceted three-dimensional (3-D) islands during growth of Si1−xGex alloys on Si(100) has been investigated by low-energy electron microscopy (LEEM). The formation of the islands in this alloy system does not involve 3-D nucleation, but rather proceeds continuously via a precursor array of shallow, stepped mounds on the surface that result from the inherent morphological instability of the strained alloy film.
Identification of genetic susceptibility to childhood cancer through analysis of genes in parallel

Clinical cancer genetic susceptibility analysis typically proceeds sequentially, beginning with the most likely causative gene. The process is time consuming and the yield is low, particularly for families with unusual patterns of cancer. We determined the results of in parallel mutation analysis of a large cancer-associated gene panel. We performed deletion analysis and sequenced the coding regions of 45 genes (8 oncogenes and 37 tumor suppressor or DNA repair genes) in 48 childhood cancer patients who also (i) were diagnosed with a second malignancy under age 30, (ii) have a sibling diagnosed with cancer under age 30, and/or (iii) have a major congenital anomaly or developmental delay. Deleterious mutations were identified in 6 of 48 (13%) families, 4 of which met the sibling criteria. Mutations were identified in genes previously implicated in both dominant and recessive childhood syndromes, including SMARCB1, PMS2, and TP53. No pathogenic deletions were identified. This approach has provided efficient identification of childhood cancer susceptibility mutations and will have greater utility as additional cancer susceptibility genes are identified. Integrating parallel analysis of large gene panels into clinical testing will speed results and increase diagnostic yield. The failure to detect mutations in 87% of families highlights that a number of childhood cancer susceptibility genes remain to be discovered.
Chronic Pain and Suicide: Understanding the Association

Chronic pain conditions are associated with an elevated risk for suicide. Of particular importance is the question of why pain conditions might be linked to increased suicide risk. We discuss the association between chronic pain and psychological pain, particularly in the context of depression, and the use of suicide as an attempt to escape from what is perceived as unbearable suffering. We also consider the role that chronic pain may play in increasing the capacity for suicide. Bridging across research areas and drawing on the interpersonal-psychological theory of suicide, we suggest that chronic pain may facilitate the development of a key risk factor for suicide: fearlessness about death. Given that chronic pain can lead to (and be exacerbated by) depression, engender hopelessness, facilitate a desire for escape through death, and erode the natural fear of dying, clinicians must be aware of psychological processes that can combine to create elevated suicide risk in patients with chronic pain, and they should also assess and treat suicide risk factors in these patients.
Magnetic field detection in sockeye salmon

Previous research has indicated that lake-migrating sockeye salmon fry have compass directional preferences, cued in part by magnetic fields. This paper reports the results of experiments designed to compare the magnetosensory system of salmon with those of other organisms. Unlike birds, the fry did not reverse their compass orientation 180° when the magnetic field's vertical component was inverted, but rather displayed northerly (31°) orientation similar to that of fry in two different control conditions (325° and 22°). These results agreed with the 349° bearing displayed in 1979. Magnetized material (implicated as possible transducers in the magnetosensory systems of bacteria, honeybees, and homing pigeons) was not found (<2 × 10−7 e.m.u.) in 26 out of 30 fry examined. The material in the other 4 was probably environmental contamination, and not part of a sensory system. The mechanism of magnetic detection in salmon remains unknown, but consideration of the evolution and life history of the fish provides some clues as to the possible nature of the mechanism.