cssi/SciSciGPT-SciSciNet huggingface dataset:
Collaborative Workshop for Women in Mathematical Biology

Biological systems are complex and highly interconnected. Despite increasing amounts of information collected, it is not always clear how to use these data to make conclusions and predictions. Mathematical models are powerful tools in biology because they allow us to abstract the biological system in order to frame questions, explore patterns and synthesize information. Indeed, we are writing these remarks during the COVID-19 Pandemic which has illustrated in a staggering way the importance of quantitative modeling in aiding our understanding of complex biological processes. This volume contains the scientific and collaborative work from the Collaborative Workshop for Women in Mathematical Biology. The workshop brought together forty-five researchers to collaborate on seven problems each of which used mathematics to understand complex biological systems. The workshop was held at the Institute of Pure and Applied Mathematics on the campus of University of California, Los Angeles from June 17-21, 2019 in Los Angeles, CA and was organized by Rebecca Segal, Blerta Shtylla, and Suzanne Sindi. The articles contained in this volume were initiated during the intensive one-week workshop and continued through follow-up collaborations afterwards.
Research Note---Toward a Causal Interpretation from Observational Data: A New Bayesian Networks Method for Structural Models with Latent Variables

Because a fundamental attribute of a good theory is causality, the information systems (IS) literature has strived to infer causality from empirical data, typically seeking causal interpretations from longitudinal, experimental, and panel data that include time precedence. However, such data are not always obtainable and observational (cross-sectional, nonexperimental) data are often the only data available. To infer causality from observational data that are common in empirical IS research, this study develops a new data analysis method that integrates the Bayesian networks (BN) and structural equation modeling (SEM) literatures. Similar to SEM techniques (e.g., LISREL and PLS), the proposed Bayesian networks for latent variables (BN-LV) method tests both the measurement model and the structural model. The method operates in two stages: First, it inductively identifies the most likely LVs from measurement items without prespecifying a measurement model. Second, it compares all the possible structural models among the identified LVs in an exploratory (automated) fashion and it discovers the most likely causal structure. By exploring the causal structural model that is not restricted to linear relationships, BN-LV contributes to the empirical IS literature by overcoming three SEM limitations (Lee, B., A. Barua, A. B. Whinston. 1997. Discovery and representation of causal relationships in MIS research: A methodological framework. MIS Quart.21(1) 109--136)---lack of causality inference, restrictive model structure, and lack of nonlinearities. Moreover, BN-LV extends the BN literature by (1) overcoming the problem of latent variable identification using observed (raw) measurement items as the only inputs, and (2) enabling the use of ordinal and discrete (Likert-type) data, which are commonly used in empirical IS studies. The BN-LV method is first illustrated and tested with actual empirical data to demonstrate how it can help reconcile competing hypotheses in terms of the direction of causality in a structural model. Second, we conduct a comprehensive simulation study to demonstrate the effectiveness of BN-LV compared to existing techniques in the SEM and BN literatures. The advantages of BN-LV in terms of measurement model construction and structural model discovery are discussed.
The art of pure cinema: Hitchcock and his imitators: BRUCE ISSACS, 2020 New York, Oxford University Press pp. 272, illus., notes, bibliography, filmography, index $39.95 (paperback)

Years ago, while attending Brooklyn College, I had a professor named Foster Hirsch. Hirsch, one of the leading film scholars in the country, most especially in film noir, has an extensive knowledge...
Anastomotic leak in patients with acute complicated diverticulitis undergoing primary anastomosis: risk factors and the role of diverting loop ileostomy

Recent data has suggested that primary anastomosis (PA), with or without a diverting loop ileostomy (DLI), is a safe option for the treatment of acute complicated diverticulitis. This study aimed to evaluate risk factors associated with anastomotic leak in patients who underwent a sigmoid colectomy with PA and to determine whether a DLI was protective against a clinically significant anastomotic leak. Patients with acute complicated diverticulitis who underwent a laparoscopic or open sigmoid colectomy with PA, with or without a DLI, were identified in the NSQIP PUF(2016–2017). The rates of anastomotic leak, receipt of DLI, and type of leak management were compared. Multivariate logistic regression was performed. There were 497 patients identified. Seventy-nine(15.9%) patients had a DLI, while 418 (84.1%) did not. Twenty-six anastomotic leaks were identified (5.2%). On multivariate analysis, current smoking (OR 4.02; 95% CI 1.44–11.26) and chronic steroid use (OR 3.84; 95% CI 1.16–12.69) were significantly associated with an increased risk of leak. Of the 26 patients with anastomotic leaks, 5 (19.2%) had a DLI. There was no significant difference in the rate of leak between those with a DLI(5; 6.3%) and those without(21; 5.3%; p = 0.59). Patients who had a DLI were significantly less likely to experience an anastomotic leak requiring re-operation (p < 0.01). Regardless of the presence of a DLI, chronic steroid use and smoking are associated with an increased risk of anastomotic leak in patients with acute complicated diverticulitis undergoing colectomy with PA. The presence of a diverting loop ileostomy is protective against re-operation.
A Case of Massive Diphenhydramine and Naproxen Overdose.

Abstract Background Diphenhydramine, a first generation H1 histamine receptor antagonist, is a commonly used nonprescription medication that is used for the treatment of allergy, as a sleep aid, or combined with cough and cold remedies. Naproxen, a nonsteroidal anti-inflammatory drug (NSAID), is used commonly for analgesia. Although most cases of diphenhydramine or naproxen overdose require excellent supportive care only, meticulous attention should be given to cardiovascular and neurologic status. Case Report A 22-year-old woman presented with altered mental status secondary to intentional ingestion of 240 combination caplets of naproxen sodium 220 mg and diphenhydramine hydrochloride 25 mg. While in the emergency department, she manifested a wide-complex tachycardia in the setting of hypotension that required repeated administration of sodium bicarbonate to overcome the sodium channel blockade caused by diphenhydramine. Aggressive potassium repletion was performed simultaneously. Her clinical course was complicated by status-epilepticus that required intubation. Orogastric lavage was performed, which returned blue pill slurry consistent with the ingested caplets. The patient was extubated on hospital day 2 and transferred to psychiatry thereafter. Why Should an Emergency Physician Be Aware of This? In light of recent social media trends, such as the “Benadryl challenge” and its widespread availability, emergency providers should be familiar with diphenhydramine toxicity, especially the life-threatening neurologic consequences and risk of cardiovascular collapse. NSAIDs, such as naproxen, and other nonprescription analgesics are becoming more and more important in light of the current opioid crisis. There should be an emphasis on understanding these medications and their potential implications when taken in overdose.
Convergent flight morphology among Müllerian mimic mutualists.

Mullerian mimicry involves a signal mutualism between prey species, shaped by visually hunting predators, and recent work has emphasized the importance of color pattern. Predators respond to more than color pattern, however, and other traits are much less studied. This article examines the hypothesis of convergent evolution in flight-related morphology among eight mimicry complexes composed of 51 butterfly species (Nymphalidae, Danainae, Ithomiini) from a single community in Ecuador. Phylogenetic comparative analyses of 14 variables indicated strong morphological differences between mimicry complexes belonging to three clusters of morphological space ("large yellow transparent," "tiger," and "transparent"), not the eight predicted based on color pattern alone. Analyses found convergence within mimicry complexes, convergence between mimicry complexes within morphospace clusters, and divergence between mimicry complexes from different morphospace clusters. These three clusters differed in size, and body and wing shape, predicting that flight biomechanics also converge (i.e., locomotor mimicry). Potential constraints on evolution of morphological mimicry related to predator discrimination, and evolutionary rates, likely e xplain why flight-related morphology differences were limited to three clusters of morphological space. Finally, the added complexity that flight-related morphology brings to signals between predator and prey indicates that evolutionary switches in color pattern are not all equally likely, potentially limiting the evolution of color patterns if they do not match morphology.
Treatment planning considerations in the older adult with periodontal disease.

Periodontal health in the elderly is influenced by numerous factors, including systemic conditions, patient compliance, age-associated changes, and restorative procedures. The numerous comorbidities seen in the elderly necessitate individualized approaches for treatment planning. In this paper, we review how age, comorbidities, oral hygiene, and restorative dental procedures collectively influence the treatment and management of the periodontium in the elderly. The elderly population is predicted to double in 30 years, which will have an economic impact the dental profession needs to plan for. Preventative and noninvasive treatment, supportive periodontal therapy, and patient-specific maintenance plans are imperative to maintaining oral health in the older population. Multiple coexisting changes, including xerostomia, altered wound healing, altered bone physiology, altered microbiome, and diminished plaque control, can add complexity to periodontal management. Considerations of the patient's general health, the selected periodontal treatment plan, and the selected completed restorative procedures need to be considered. The influence of caries, fixed prosthodontics, partial dentures, shortened dental arch, and implant therapy can have unintended impacts on periodontal health in the elderly. Adverse periodontal outcomes in the elderly can be minimized by carefully assessing the patient's medical history, impact of medications, functional needs, properly finishing and contouring restorations to avoid plaque accumulation, and designing restorations to allow access for hygiene. Partial dentures can be a source of plaque accumulation leading to periodontal disease, caries, and recession around abutment teeth. A shortened dental arch should be considered as a functional and cost-effective alternative to partial dentures. With dental implants, the patient's tissue phenotype, keratinized tissue quantity, risk of peri-implantitis, and patient access for maintaining adequate oral hygiene are all important to consider. Implant risk-assessment tools show promise by providing a systematic approach for early diagnosis to avoid future complications.
Genome of the bi-annual Rio Pearlfish (Nematolebias whitei), a killifish model species for Eco-Evo-Devo

The Rio Pearlfish Nematolebias whitei is a bi-annual killifish species inhabiting seasonal pools of the Rio de Janeiro region that dry twice per year. Embryos enter dormant diapause stages in the soil, waiting for the inundation of the habitat which triggers hatching and commencement of a new life cycle. This species represents a convergent, independent origin of annualism from other emerging killifish model species. While some transcriptomic datasets are available for Rio Pearlfish, thus far a sequenced genome has been unavailable. Here we present a high quality, 1.2Gb chromosome-level genome assembly, genome annotations and a comparative genomic investigation of the Rio Pearlfish as representative of a vertebrate clade that evolved environmentally-cued hatching. We show conservation of 3-D genome structure across teleost fish evolution, developmental stages, tissues and cell types. Our analysis of mobile DNA shows that Rio Pearlfish, like other annual killifishes, possesses an expanded transposable element profile with implications for rapid aging and adaptation to harsh conditions. We use the Rio Pearlfish genome to identify its hatching enzyme gene repertoire and the location of the hatching gland, a key first step in understanding the developmental genetic control of hatching. The Rio Pearlfish genome expands the comparative genomic toolkit available to study convergent origins of seasonal life histories, diapause, and rapid aging phenotypes. We present the first set of genomic resources for this emerging model organism, critical for future functional genetic and multi-omic explorations of "Eco-Evo-Devo" phenotypes in resilience and adaptation to extreme environments. Significance: Seasonal or annual killifishes are emerging models for aging, life history adaptions to extreme environments, and ecological evolutionary developmental biology (Eco-Evo-Devo). Most studies have thus far focused on the African turquoise killifish Nothobranchius furzeri and the South American Austrofundulus limneaus. We sequenced and analyzed the genome of the Rio Pearlfish Nematolebias whitei from the Rio de Janeiro region, a seasonal species representing a convergent origin of seasonality from other sequenced killifish species, strengthening the comparative potential of Aplocheiloid killifishes as a model clade for the comparative and functional genomics of animal resilience to environmental change.
Computer Simulation of the Hydrodynamic and Salinity Behavior of Weeks Bay, Alabama, at Equatorial Tide Conditions

Whereas the long term goal of the work described focuses on issues related to estuaries in general, specific attention in this paper focuses on one – Weeks Bay, Alabama. This estuary is one of seventeen estuarine research reserves established as “natural field laboratories” for long-term scientific and educational programs (See Figure 1). Initially, Weeks Bay will be assumed to be a well mixed estuary such that two-dimensional (depth averaged) modeling can be used. The Waterways Experiment Station Implicit Flooding Model (WIFM), developed by the U.S. Army Corps of Engineers, Vicksburg, Mississippi is used. Complete data sets at equatorial tidal conditions were chosen from the field data available. Good agreement of model results with field measured water elevations was noted. These results are typical of the kind of agreement that is expected from two-dimensional depth averaged model simulations. As anticipated, there seems to be little or no movement of salt along the western shoreline when the Bon Secour Bay salinities are low. This indicates selective flow of Fish River water down the western side of the bay with a corresponding preference for Bon Secour Bay water to flow along the eastern shore.
On Novel Static Spherically Symmetric Solutions of Einstein’s equations and the Cosmological Constant Problem

A novel class of static spherically symmetric (SSS) solutions of Einstein�s equations are explicitly constructed in terms of a family of admissible radial functions...
Characterization of human bone marrow fibroblast colony-forming cells (CFU-F) and their progeny

The bone marrow stromal cell population is comprised of fibroblasts, endothelial cells, fat cells and “reticular cells.” The characteristics and the regulatory role in hematopoiesis of each of these cell types are unknown. A liquid culture system has been used to clone and to characterize human bone marrow fibroblast colony-forming cells (CFU-F). The linear relationship between the number of cells plated and the number of colonies formed suggests that fibroblast colonies originate in a single cell. Bone marrow CFU-F were adherent and nonphagocytic. The majority (90% ± 2%) were less dense than 1.070 g/cu cm. Velocity sedimentation separation demonstrated a heterogeneous CFU-F sedimentation rate, with a modal sedimentation of 4.95 ± 0.15 mm/hr. Analysis of CFU-F proliferative status by the thymidine suicide technique indicated that this cell was noncycling in individuals with undisturbed bone marrow function. Some of the more distinctive products of fibroblasts, other stromal cells, and hematopoietic colony-forming cells were used as positive and negative markers for CFU-F and the cells derived from them in vitro. Complement-mediated cytotoxicity using anti-Ia and anti-factor-VIII antigen antisera did not inhibit fibroblast colony formation. In contrast, a striking reduction of granulocyte-macrophage colony formation (CFU-c) was seen when bone marrow cells were treated with anti-Ia antiserum. Immunofluorescence staining was used to characterize the cells derived from CFU-F in vitro. No staining was observed after incubation of subconfluent cultures with anti-Ia and anti-factor-VIII antigen antisera. A positive immunofluorescent staining was obtained when isolated antibodies against three of the main proteins of bone marrow matrix: type I collagen, type III collagen, and fibronectin were used. Ultrastructural analysis showed that CFU-F progeny, in contrast to endothelial cells, did not contain Weibel-Palade bodies. These data support the conclusion that the colonies described in this study are of fibroblastic nature.
Parents of the battered child: a multidisciplinary group therapy approach to life-threatening behavior.

: This paper reports the demographic findings and the experience of a three-year, multidisciplinary group psychotherapy program, with 31 child-abusing families. No predictive demographic characteristics were identified. The abuse of children ranged from mild bruising to severe brain damage and multiple fractures. Group therapy as an intervention procedure had its successes and failures. The dynamics of male-female co-therapists, the peer group sharing, and the capacity to ultimately verbalize inadequacies in the parenting role were crucial factors in therapy. As an experiential encounter the study gives a poignant insight into the personal and family pathology of parents who abuse their children.
Union-Nonunion Gender Wage and Benefit Differentials across Establishment Sizes

Based on data from the National Longitudinal Surveys of Youth (NLSY), both male and female workers in larger establishments receive not only higher wages but also have a higher probability of receiving benefits than those in smaller establishments. This phenomenon reinforces the well documented size effect. This study also provides evidence of vast gender differences in estimated union effects on the different components of the compensation structure. Hence unions should not treat both genders similarly with respect to wages and benefits. Specifically, unions may be successful in attracting more female workers to join rank and file if unions could play an active role in making available maternity (paternity) leave, and also provided opportunities for women to join large establishments.
A neuronal representation of the location of nearby sounds

Humans can accurately perceive the location of a sound source—not only the direction, but also the distance1,2,3,4,5,6,7,8,9. Sounds near the head, within ducking or reaching distance, have a special saliency. However, little is known about this perception of auditory distance. The direction to a sound source can be determined by interaural differences, and the mechanisms of direction perception have been studied intensively1; but except for studies on echolocation in the bat10, little is known about how neurons encode information on auditory distance. Here we describe neurons in the brain of macaque monkeys (Macaca fascicularis) that represent the auditory space surrounding the head, within roughly 30 cm. These neurons, which are located in the ventral premotor cortex, have spatial receptive fields that extend a limited distance outward from the head.
Comparison of two treatment approaches for prostate cancer: intensity-modulated radiation therapy combined with 125I seed-implant brachytherapy or 125I seed-implant brachytherapy alone.

The purpose of this study was to assess the results of two different treatment approaches for clinically localized prostate cancer: intensity modulated radiation therapy (IMRT) followed by 125 Iodine ( 125 I) seed implant brachytherapy and 125 I seed implant brachytherapy alone. Thirty most recent consecutive patients were studied. The sample population consisted of 15 cases treated with IMRT (50.4 Gy), followed by 125 I seed implant boost (95 Gy), and 15 cases treated with 125 I seed implant only (144 Gy). Established dosimetric indices and various clinical parameters were analyzed. In addition, the acute urinary morbidities of the two treatment approaches, as assessed by the International Prostate Symptom Score (IPSS), were also evaluated and compared. In our series, IMRT followed by 125 I seed implant brachytherapy s lightly increased the acute urinary morbidity compared with 125 I seed implant brachytherapy alone. In addition, there was no statistically significant correlation between the IPSS and the maximum or mean urethral dose. Combination of IMRT and seed implant brachytherapy presents an alternative opportunity to treat clinically localized prostate cancer. Its full potential needs to be further investigated.
The last 50 years in growth theory and the next 10

This article offers a personal view of the main achievements of (broadly) neoclassical growth theory, along with a few of the important gaps that remain. It discusses briefly the pluses and minuses of two major recent lines of research: endogenous growth theory and the drawing of causal inferences from international cross-sections, and criticizes the widespread contemporary tendency to convert the normative Ramsey model into a positive representative-agent macroeconomic model applying at all frequencies. Finally, it comments on the articles appearing in this symposium.
Chromosome Aberrations in Embryos From In Vivo Aged Chicken Sperm

Abstract The effects of in vivo aging of spermatozoa on chromosome aberrations in early developing chick embryos were studied. There were aberrant chromosomes in all metaphase cells in one of 218 embryos examined or 0.458 percent for fresh sperm (1–3 days of fertile eggs) compared to seven of 315 embryos or 2.22 percent for aged sperm (9–14 days). Thus chromosome aberrations would account for about 25 percent of the expected embryonic death.
Acquired immunodeficiency syndrome (AIDS) in hemophiliacs.

From mid-1977 to mid-1983 the Centers for Disease Control (CDC) has received reports of more than 2,100 cases of acquired immunodeficiency syndrome (AIDS). These cases had either biopsy confirmed Kaposi's sarcoma or a biopsy or culture confirmed life-threatening opportunistic infection, without an identifiable cause of immunosuppression. Reports of AIDS in hemophiliacs began to appear in January 1982. As of October 6, 1983, CDC has confirmed 18 reports of AIDS in United States (U.S.) hemophiliacs and 5 outside the U.S. Two had other known risk factors for AIDS. Seventeen of these cases had Pneumocystis carinii pneumonia. (PCP). The mortality rate for the 23 hemophiliac cases was 70 percent. Immunologic findings included lymphopenia, a decreased ratio of T helper/T suppressor lymphocytes, and hypergammaglobulinemia. Most hemophiliac cases did not reside in areas of high risk for AIDS. All cases had received factor and, often, other blood products in the 5 years prior to the AIDS diagnosis. The racial distribution of hemophiliac AIDS patients resembled that of transfusion-associated AIDS patients. Hemophiliac AIDS patients resembled both transfusion-associated and IV-drug abuser AIDS patients and differed from homosexuals with AIDS in regard to associated diagnoses. The epidemiology of these cases is consistent with the possibility that AIDS is caused by an agent transmissible through blood products. These data support the need for current blood product related precautions issued by the National Hemophilia Foundation and by the Public Health Service.
Tool Compounds Robustly Increase Turnover of an Artificial Substrate by Glucocerebrosidase in Human Brain Lysates

Mutations in glucocerebrosidase (GBA1) cause Gaucher disease and also represent a common risk factor for Parkinson’s disease and Dementia with Lewy bodies. Recently, new tool molecules were described which can increase turnover of an artificial substrate 4MUG when incubated with mutant N370S GBA1 from human spleen. Here we show that these compounds exert a similar effect on the wild-type enzyme in a cell-free system. In addition, these tool compounds robustly increase turnover of 4MUG by GBA1 derived from human cortex, despite substantially lower glycosylation of GBA1 in human brain, suggesting that the degree of glycosylation is not important for compound binding. Surprisingly, these tool compounds failed to robustly alter GBA1 turnover of 4MUG in the mouse brain homogenate. Our data raise the possibility that in vivo models with humanized glucocerebrosidase may be needed for efficacy assessments of such small molecules.
Variations in municipal bond default risk premia by term-to-maturity

Abstract A recent study by McInish of the influence of term-to-maturity on municipal bond default risk premia concluded that default risk premia were not invariant with respect to maturity. That study, as well as an earlier one by Robinson, failed to consider the effects of issuer credit quality. Using a large cross-sectional sample of general obligation bonds sold between 1977 and 1980, the influence of issuer credit quality on the relationship between term-to-maturity and default risk premia is investigated. The results indicate that default risk premia were an increasing function of maturity, and that this effect was larger for lower rated bonds.
Ultrastructure of pineal parenchymal neoplasms.

The fine structure of two pineal parenchymal neoplasms has been described. The tumors contained a predominance of small, poorly differentiated cells with prominent nuclei and scanty cytoplasm. These cells were similar to those found in medulloblastomas, primitive cerebral neuroectodermal tumors, and fetal cerebellum and cerebrum. Some cells contained 9+0 cilia, dense core vesicles, and processes containing microtubules and numerous dense core and clear vesicles, suggesting neuronal differentiation. Astrocytic elements were also present. This study suggests that the predominant cells of these tumors are primitive neuroectodermal elements which have the potential to differentiate along several different lines.
In Vitro Biomechanical Comparison of Polypropylene Mesh, Modified Three‐Loop Pulley Suture Pattern, and a Combination for Repair of Distal Canine Achilles' Tendon Injuries

Objective— To compare mechanical stability between a novel polypropylene mesh repair (Mesh), a modified 3-loop pulley suture (Suture), and a combination of the techniques (Suture+Mesh) for the repair of distal canine Achilles' tendon ruptures. Study Design— In vitro mechanical evaluation. Sample Population— Cadaveric canine Achilles' tendon/calcaneus units (n=34). Methods— Constructs were loaded under tension to failure in a materials testing machine with synchronized kinematic analysis. Ultimate load to failure, global construct stiffness, and force required to reach 1 and 3 mm gap formation was recorded. Results— Ultimate load to failure was greatest for the Suture+Mesh group and lowest for the Suture group. The Suture+Mesh technique afforded a significantly greater global stiffness than the Suture or Mesh treatments. Force to generate 1 and 3 mm gap formation was greatest with the Suture group. Conclusions— The Suture+Mesh group had the highest ultimate load to failure and afforded the greatest global stiffness though it had no added benefit to resist local gap formation at the repair. Clinical Relevance— Achilles' ruptures repaired with suture can be augmented with mesh to increase the ultimate load to failure, but as currently tested, there was a decrease in resistance to gap formation At this time we cannot recommend Mesh or the Suture+Mesh techniques without further testing.
A seismic velocity-confining pressure relation, with applications

In a rock specimen, the constituent minerals and microcracks dictate the sample's response to stress. This behaviour is reflected in the compressional and shear velocities measured as a function of confining pressure in the laboratory, and thus laboratory velocities have been employed to solve important geologic problems. To further this usage, an empirical equation relating velocity to confining pressure is proposed. This equation is used to curve-fit Vp and Vs data for a range of samples and is shown to give excellent results with well-constrained parameters. Expressing a complete V-P data set is reduced to reporting four constants, since data interpolation and extrapolation are accurately performed using this equation. Once the data are curve-fit, pressure derivatives, velocity anisotropies and elastic constants as functions of pressure are simply determined.
Positive and negative regulatory inputs restrict pax-6/vab-3 transcription to sensory organ precursors in Caenorhabditis elegans

The Pax-6 gene encodes a transcription factor essential for the development of eyes and other sensory organs in species ranging from planaria to mice. Because Pax-6 activity can be both necessary and sufficient for eye organogenesis, much work has focused on PAX-6 function and regulation of target genes. However, less is known about the genetic mechanisms that establish the Pax-6 expression pattern. We have utilized Caenorhabditis elegans as a relatively simple model system to characterize the regulation of Pax-6 transcription in sensory organ precursors. In C. elegans males, two sensory mating structures, the copulatory spicules and the post-cloacal sensilla, are formed from stereotyped divisions of the two post-embryonic blast cells, B.a and Y.p, respectively. A C. elegans pax-6 transcript, vab-3, is necessary for the development of these sensory structures. Using a green fluorescent protein (GFP)-based vab-3 transcriptional reporter, we show that expression is restricted to the sensory organ lineages of B.a and Y.p. Transcription of vab-3 in the tail region of the worm requires the Abdominal B homeobox gene, egl-5. Opposing this activation, a transcription factor cascade and a Wnt signaling pathway each act to restrict vab-3 expression to the appropriate cell lineages. Thus we have identified multiple genetic pathways that act to restrict pax-6/vab-3 gene expression to the sensory organ precursor cells.
Controlled Environments Alter Nutrient Content of Soybeans

Abstract Information about compositional changes in plants grown in controlled environments is essential for developing a safe, nutritious diet for a Controlled Ecological Life-Support System (CELSS). Information now is available for some CELSS candidate crops, but detailed information has been lacking for soybeans. To determine the effect of environment on macronutrient and mineral composition of soybeans, plants were grown both in the field and in a controlled environment where the hydroponic nutrient solution, photosynthetic flux (PPF), and CO2 level were manipulated to achieve rapid growth rates. Plants were harvested at seed maturity, separated into discrete parts, and oven dried prior to chemical analysis. Plant material was analyzed for proximate composition (moisture, protein, lipid, ash, and carbohydrate), total nitrogen (N), nonprotein N (NPN), nitrate, minerals, amino acid composition, and total dietary fiber. The effect of environment on composition varied by cultivar and plant part. Chamber-grown plants generally exhibited the following characteristics compared with field-grown plants: 1) increased total N and protein N for all plant parts, 2) increased nitrate in leaves and stems but not in seeds, 3) increased lipids in seeds, and 4) decreased Ca:P ratio for stems, pods, and leaves. These trends are consistent with data for other CELSS crops. Total N, protein N, and amino acid contents for 350 ppm CO2 and 1000 ppm CO2 were similar for seeds, but protein N and amino acid contents for leaves were higher at 350 ppm CO2 than at 1000 ppm CO2. Total dietary fiber content of soybean leaves was higher with 350 ppm CO2 than with 1000 ppm CO2. Such data will help in selecting of crop species, cultivars, and growing conditions to ensure safe, nutritious diets for CELSS.
Prevalence of human immunodeficiency virus testing and high-risk human immunodeficiency virus behavior among 18 to 22 year-old students and nonstudents: results of the National Survey of Family Growth.

Background: This study characterized human immunodeficiency virus (HIV) testing and high-risk behavior among 18 to 22 year-old college students and nonstudents. Methods: Data from 18 to 22 year-olds (n = 2007) in Cycle 6 of the National Survey of Family Growth, a nationally representative survey conducted between March 2002 and February 2003, were analyzed using univariate and multivariate methods. Results: The estimated percentage of 18- to 22-year-olds ever tested for HIV excluding during blood donation was 34.2% (95% confidence interval [CI]: 31.6%―36.8%) and was less common among students than nonstudents after adjusting for age, gender, race/ethnicity, and marital status (adjusted OR [odds ratios]: 0.54; 95% CI: 0.40-0.73). The estimated percentage tested during the previous year was 18.1% (95% CI: 16.1%―20. 1%), and there was no difference between students and nonstudents (adjusted OR: 0.76; 95% CI: 0.55-1.05). The estimated percentage of 18- to 22-year-olds reporting any high-risk HIV behavior was 37.5% (95% CI: 34.4%―40.5%). Of these, only 28.3% (95% CI: 24.5%-32.0%) had an HIV test within the year before the study, and this did not vary by student status (adjusted OR: 0.91; 95% CI: 0.62―1.35). Conclusions: More than one-third of this young adult population reported high-risk HIV behavior. Of these, less than one-third was tested for HIV during the year before the study. These results indicate that enhanced HIV testing and prevention efforts are needed for students and nonstudents, and that HIV testing in this age group should be monitored over time.
Phenotypic plasticity, intraguild predation and anti‐cannibal defences in an enigmatic polymorphic ciliate

Summary 1 Inducible trophic polymorphisms are greatly underappreciated forms of phenotypic plasticity that allow organisms to respond dynamically to the environmental variation by enabling them to change the trophic level upon which they feed. Although inducible trophic polymorphisms occur in a diverse array of organisms, their costs, benefits and their consequences for long-term population and community dynamics are poorly understood. 2 We studied the inducible trophic polymorphism of the freshwater hymenostome ciliate Tetrahymena vorax, whose isogenic populations can contain three distinct morphs: pyriform, bacterivorous microstomes; larger, carnivorous macrostomes; and elongate, ‘tailed’ microstomes. We tested whether (i) the tailed microstome constitutes an inducible defence against macrostomes and (ii) the transformation of microstomes into macrostomes is size-dependent. We also describe the dynamics of the three morphs in the presence and absence of an intraguild prey (Colpidium) across a gradient of growth medium concentrations to infer potential trade-offs in the success of different morphs at different productivity levels. 3 Macrostomes do not discriminate between pyriform microstomes and readily consumed heterospecific prey (Colpidium). Tailed microstomes display greatly reduced susceptibility to consumption by macrostomes as compared with undefended, pyriform microstomes. Morph dynamics are consistent with the hypothesis that tailed microstomes function as an inducible defence against cannibalism; tailed microstomes and macrostomes appear simultaneously, in both the presence and absence of Colpidium. At low productivity, T. vorax achieves higher rates of growth when feeding on Colpidium instead of on bacteria. At higher productivity, this pattern is reversed, with growth rates maximized in the absence of Colpidium. 4 The reduced consumption rate of tailed microstomes by cannibalistic macrostomes, together with the simultaneous induction of tailed microstomes and macrostomes, suggests that both morphs comprise a coordinated adaptive response to the presence of intraguild prey.
NUCLEAR SCATTERING OF LOW-ENERGY PIONS

We have estimated the parameters of the optical potential for low energy pion-nucleus scattering from the values obtained empirically in the analysis of pionic atom data. The ambiguities in these parameters are discussed. The shape of the low energy elastic scattering cross section for light elements is particularly sensitive to the relative strength of the repulsive and velocity-dependent attractive parts of the optical potential, and is well reproduced by pionic atom parameters. Absorption is the dominant reaction channel at low energies. Pion nucleon phase shifts are used to extrapolate optical model parameters to higher energies. The behavior of the elastic and inelastic angular distributions and of various partial cross sections is discussed, and compared with experiment.NUCLEAR REACTIONS Calculated pion-nucleus optical potential, elastic scattering, inelastic scattering and partial cross sections. 30, 40, 50 MeV on various targets. 116-220 MeV on individual targets.
H2S Abatement in a biotrickling filter using iron(III) foam media

Abstract Airstreams polluted with H 2 S at inlet loads ranging from 2.4 to 40.9 g H 2 S m −3 h −1 were treated in a biotrickling reactor packed with hematite bearing, open pore foam units, at Empty Bed Residence Times (EBRT) ranging from 20 to 60 s over a period of 80 d, with almost complete removal of the pollutant from the startup of the system. The media had been seeded with sludge from a local water works facility, and removal efficiencies in excess of 80% were consistently observed along the operation of the reactor, with an average of 98%. Based on section performance, being a section one third of the bed length, observed elimination capacities (EC) reached up to 88.7 g H 2 S m −3 h − 1 and 72.0 g H 2 S m −3 h −1 at section EBRT of 10 and 7 s, respectively. The observed EC values compared much better than data reported on other packed bed reactors using biological iron oxidization to treat H 2 S airstreams indirectly, and so did it when comparing the EC per unit of specific area in a similar study using polyurethane (PU) foams. Further, and unlike PU packed biofilters, no compaction occurred due to the iron foam rigidity, which translated in much better observed gas phase pressure drop as opposed to other conventional biofilters. Denaturing gel gradient electrophoresis was performed on the biomass collected in the packing after the biofilter service, and it was found that though a multi bacterial colony was seeded in the system via the sludge, the only surviving genus was the iron oxidizing Alicyclobacillus spp.
Algorithm 867: QUADLOG—a package of routines for generating Gauss-related quadrature for two classes of logarithmic weight functions

A collection of subroutines and examples of their uses are described for the quadrature method developed in the companion article. These allow the exact evaluation (up to computer truncation and rounding errors) of integrals of polynomials with two general types of logarithmic weights, and also with the corresponding nonlogarithmic weights. The recurrence coefficients for the related nonclassical orthogonal polynomials with logarithmic weight functions can also be obtained. Tests of accuracy on various platforms are presented.The routines are usable from Fortran, C, and Cpp programs conforming to any of at least six international programming-language standards.
The Isomerization Equilibrium between Cis and Trans Chloride Ruthenium Olefin Metathesis Catalysts from Quantum Mechanics Calculations

The cis−trans chloride isomerization of a ruthenium olefin metathesis catalyst is studied using quantum mechanics (B3LYP DFT), including the Poisson−Boltzmann (PBF) continuum approximation. The predicted geometries agree with experiment. The energies in methylene chloride, lead to ΔG = −0.70 kcal/mol and a cis:trans ratio of 76:24, quite close to the experimental value of ΔG = −0.78 kcal/mol or c:t 78:22. In contrast, we predict that in benzene c:t = 4:96 in agreement with the experimental observation of only the trans isomer. Our calculated relative activation energies explain the observed difference in initiation rates and suggest that each isomer should be isolable in high ratio by simply changing solvent.
Synthesis and superconducting properties of (Tl1-xBix)Sr2Ca2Cu3O9

Abstract High temperature superconductors (Tl1−xBix)Sr2Ca2Cu3O9 have been prepared for x = 0.1 to 0.5 by solid state reactions in sealed gold tubes with Tc's in the range 115 to 120 K. They all have tetragonal unit cells (a ≈ 3.8 and c ≈ 15 A) and are isostructural to TlBa2Ca2Cu3O9 and (Tl0.5Pb0.5)Sr2Ca2Cu3O9. Electron diffraction patterns of these compounds did not reveal any superstructure, which is common among Bi2Sr2Can−1CunO2n+4 superconductors. Variation of c lattice parameter with x and comparison of unit cell parameters of (Tl0.5Pb0.5)Sr2Ca2Cu3O9 with (Tl0.5Bi0.5)Sr2Ca2Cu3O9 suggests that formal oxidation state of Bi in the title compounds is close to or slightly above 3+.
Removal of strontium from milk.

Columns of pulverized modified bone were shown to be effective for the removal of Sr/sup 85/ from milk. Analyses of milk before and after treatment are given, and the method used in bone preparation is discussed. (C.A.)
Tools for building knowledge-based tutors

DESCRIBED IS THE PROCESS OF ENCODING TUTORING KNOWLEDGE in a knowledge-based tutor, and the tools that facilitate identifying the tutoring knowledge and the process of representing it.Knowledge representation is explained in terms of modelling domain knowledge, human thinking, learning processes, and tutoring strategies. A uniform language is proposed for storing tutoring primitives, including lessons, topics, and presentations.Knowledge acquisition is described as a methodology for identifying and encoding the expertise used by teachers to reason about tutoring.Control knowledge is explained in terms of the machine’s ability to select a topic or response for an individual student and then customize its discourse and dynamically modify its examples, questions, or descriptions for that student.
Microsurgical anatomy of the atlantal part of the vertebral artery

BACKGROUND Microanatomy of the vertebral artery has been the subject of multiple studies. However, none of them has covered every aspect of microvascular anatomy of the atlantal part of the vertebral artery. MATERIALS AND METHODS Microsurgical anatomy of the atlantal part of the vertebral artery was studied in 14 cadaveric specimens. The artery was dissected using the standard microsurgical technique under operative microscope magnification. The atlantal part of the vertebral artery was divided into five segments : the foraminal, sagittal, transverse, medial condylar, and dural. The length of each segment was measured, as was the diameter of the artery. The branches of this part of the artery were identified and the distance between the point of dural entry of the artery and the midline of the atlanto-occipital dura was measured. Distance between the mastoid tip and the artery and the distance between the mastoid tip and the tip of C1 transverse process were measured. RESULTS Results of all measurements are summarized in tables and text. We discuss various anomalies, branches, and lesions of the vertebral artery and surgical approaches with new methods of managing diseases in this area.
Adventitious shoot formation on excised leaves of in vitro grown shoots of apple cultivars

Leaves taken from micropropagated shoots of several apple (Malus domestica Borkh.) cultivars were cultured in vitro on Linsmaier & Skoog (LS) medium or the rice anther culture medium of Chu et al. (N6) containing various concentrations of either benzyladenine (BA) or thidiazuron (TDZ) plus naphthaleneacetic acid (NAA). Of the TDZ concentrations tested, 10 μM was most effective and it was equivalent to, or better than, 22 μM BA for both the percentage of leaves regenerating shoots and number of shoots formed per regenerating leaf in almost every experiment. Lower concentrations of NAA (1.1 and 5.4 μM) gave best results with both BA and TDZ. N6 medium gave consistently better results than LS. Lowering total salt concentration or total N concentration of LS to that of N6 did not improve the response nor did changing the NO3:NH4 ratio. The 3–4 leaves on the most distal part of the shoot were most responsive and tended to form the most adventitious shoots. Placing the leaf cultures in the dark for the first 2–3 weeks of the culture period produced the best results. Optimum results were obtained by culturing leaves from the distal part of the shoot in the dark for 2 weeks on N6 medium containing 10 μM TDZ and 1.1 or 5.4 μM NAA, then moving the cultures to 16 h daylight at a photon flux of 60 μmol s-1m-2.
Active dendritic properties constrain input-output relationships in neurons of the central olfactory pathway in the crayfish forebrain.

Parasol cells are multimodal sensory interneurons of the hemi-ellipsoid body in the decapod forebrain. In reptant crustaceans, the hemi-ellipsoid body resides in the base of the eyecup, as an appendage to the terminal medulla. Parasol cells exhibit periodic depolarizations at a frequency of 0.5-1.0 Hz. I have investigated the role of these periodic depolarizations and their superimposed impulse bursts in affecting the input/output properties of these neurons. Parasol cells receive input from photic, olfactory, and mechanosensory pathways. Strong stimulation over any one of these pathways can lead to the generation of one or more impulse bursts in a subset of parasol cells, timed to occur at the peak of successive periodic depolarizations. A role for the periodic depolarizations in the function of the parasol cells has yet to be established. I suggest the possibility that they may act as a nonlinear amplifier that boosts spatially-summated excitatory synaptic potentials from strong or appropriate stimuli above threshold for burst generation. Another possibility includes modification of voltage-sensitive ion channels in the dendritic membrane, permitting a more effective spread of excitatory synaptic currents to impulse or burst initiating zones. Impulse bursts may be a highly effective mode of output for these neurons, especially so as they occur synchronously in a subset of cells in response to strong sensory input. Furthermore, backfiring of bursts into the dendritic tree has a brief (2-3 second) but effective suppressive action upon weak sensory input, which can thereby be masked by stronger, burst-generating input. This masking phenomenon is seen in other arthropod sensory interneurons, where its physiological basis appears to be a transient accumulation of intracellular Ca(++) ions that open calcium-sensitive potassium channels.