cssi/SciSciGPT-SciSciNet huggingface dataset:
Abstract 306: Cationic cholesterol liposomes for combination therapy to treat drug-resistant ovarian cancer

Introduction: Ovarian cancer is the fifth leading cause of cancer mortality in women, with nearly 75% of women who respond to initial platinum-based chemotherapy experiencing relapse due to drug resistance [1,2]. Liposomes are a promising solution to overcoming drug resistance due to their biocompatibility and capacity to encapsulate hydrophilic and hydrophobic drugs as well as complex small interfering RNA (siRNA), which have the potential to downregulate the expression of genes related to drug resistance [3]. We aim to synthesize and characterize a cationic liposomal system to deliver siRNA and paclitaxel (PTX) to ovarian cancer cells. Methods: Cholesterol (CHOL) liposomes were synthesized by the thin-film hydration method. Dynamic light scattering (DLS) was used to determine the size, polydispersity index (PDI), and zeta potential of the liposomes. Uptake of liposomes into OVCAR3 and OVCAR3-T40, a wild-type and a paclitaxel-resistant human adenocarcinoma cell line, was examined using fluorescence microscopy. The cytotoxicity of unloaded CHOL liposomes was evaluated through MTS assay on OVCAR3 and OVCAR3-T40 cells. Results: PTX- and siRNA-loaded CHOL liposomes had an average diameter of 114.9 ± 10.35 nm and a zeta potential of 27.6 ± 1.79 mV. Blank CHOL liposomes had an average diameter of 123.0 ± 2.49 nm and zeta potential of 32.3 ± 2.16 mV. All formulations of liposomes were cationic and formed monodisperse nanoparticles. The encapsulation efficiency of siRNA and PTX was 99.8% and 80.4% respectively. Coumarin 6, a hydrophobic model drug, was loaded into liposomes to verify cellular uptake through fluorescent imaging. Results demonstrated that the liposomal system was efficiently delivered intracellularly. Blank liposomes were used to determine the toxicity of the delivery system. The unloaded liposomes were not cytotoxic to both the wild-type and drug-resistant cell lines at concentrations up to 75 µg/mL, and therefore, cytotoxicity of drug-loaded liposomes can be attributed to paclitaxel, siRNA, or combination treatment. Conclusions: Liposomes were successfully formed with a monodisperse size, exhibited effective drug and siRNA loading, and were internalized into OVCAR3 and OVCAR3-T40 cells. Future work includes investigating the efficacy of the liposomal system in mediating gene silencing. Acknowledgements: This work was supported in part by the National Science Foundation EPSCoR Program under NSF Award # OIA-1655740 and Clemson Creative Inquiry. References: [1] Torre, L. A., CA Cancer J Clin. 2018;68(4):284-296, [2], Norouzi-Barough L., J Cell Physiol.2018;233(6):4546-4562, [3] Farra R., Pharmaceutics. 2019;11(10):547. Citation Format: Samantha Gardner, Kharimat L. Alatise, Emily Miller, Emily Grant, Angela Alexander-Bryant. Cationic cholesterol liposomes for combination therapy to treat drug-resistant ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 306.
Planning Sensing Sequences for Subsurface 3D Tumor Mapping.

Surgical automation has the potential to enable increased precision and reduce the per-patient workload of overburdened human surgeons. An effective automation system must be able to sense and map subsurface anatomy, such as tumors, efficiently and accurately. In this work, we present a method that plans a sequence of sensing actions to map the 3D geometry of subsurface tumors. We leverage a sequential Bayesian Hilbert map to create a 3D probabilistic occupancy model that represents the likelihood that any given point in the anatomy is occupied by a tumor, conditioned on sensor readings. We iteratively update the map, utilizing Bayesian optimization to determine sensing poses that explore unsensed regions of anatomy and exploit the knowledge gained by previous sensing actions. We demonstrate our method's efficiency and accuracy in three anatomical scenarios including a liver tumor scenario generated from a real patient's CT scan. The results show that our proposed method significantly outperforms comparison methods in terms of efficiency while detecting subsurface tumors with high accuracy.
Impacts of trade facilitation on modal choice and international trade flows

Abstract Over the last decade, the use of air transport to facilitate global merchandise trade has grown significantly, driven by the increasing demand for ‘just in time’ delivery of intermediate goods as well as due to the growing importance of trade between more distant countries. In this paper we analyze the effect of improved global logistics and trade facilitation on transport mode choice in international trade using the Global Trade Analysis Project (GTAP) model of global trade which we modify to incorporate modal choice. To parameterize this model, we develop a continuous modal choice model and estimate the associated elasticities of substitution between transport modes. We find that modal substitution elasticities have values ranging from 0.57 to 2.14, indicating significant response to changes in the relative cost of different modes of goods transport. The quality of logistics infrastructure is also found to influence modal choice in international trade with improved logistics performance generally leading to increased reliance on air transportation. We validate the modified and parameterized GTAP model by simulating the impact of improvements in logistics, measured as a change in the Logistics Performance Index (LPI). We find that improvement in LPI in the poorest countries of the world reduces the overall cost of transport and amount of services required to transport a given product along a given route by a given mode. Importantly, the reduction in modal cost of transport results in modal substitution. We use the framework to explore the consequences of an improvement in low income country logistics performance for GDP and economic welfare.
The Adult Hypospadias Patient: Technical Challenges in Adulthood

Hypospadias repair is usually performed during early childhood; however, sometimes this anomaly is left untreated until adulthood and in the majority of these cases the meatus is distal. The degree of curvature may have been unappreciated by both the parents and the primary care physician, and this is also fairly common in developing countries. Although patients with marked chordee and a proximal meatus will be affected by the abnormality, the disability caused by mild variants of hypospadias is less obvious. Dodd’s et al. 2008 [1] paper reported their experience with 56 adults and found that 18 (32 %) stated that they were not aware they had an abnormality of the penis. None of the 56 patients complained of voiding problems however 20 (36 %) stated when asked that they had spraying or angulation of their urinary stream. Most (95 %) of the adult patients in their series stated that they were satisfied with the appearance of their penis, whether or not this finding is attributable to patient denial/embarrassment, lack of insight about what normal is, or true satisfaction remains unclear. A survey of adults with uncorrected hypospadias involved a study of 500 consecutive men who underwent transurethral resection of the prostate or transurethral resection of bladder tumor. The investigators [2] reported that 13 % of their patients had anterior hypospadias. Sixty three percent of the patients were unaware that they had a genital anomaly, and none of them had voiding or cosmetic complaints.
Bacterial Contamination of Blood Products

Publisher Summary The risk of bacterial contamination of blood components is now receiving more attention. Septic transfusion reactions because of bacterial contamination of blood products are unusual but serious complications of transfusion. Severe hypotension and even death may result from transfusion of accumulated organisms or endotoxins in contaminated units. Bacterial contamination of blood components occurs despite adherence to careful donor screening and rigorous collection and processing procedures. Sources of bacterial contamination may include the donor venipuncture site or unsuspected donor bacteremia. The initial signs and symptoms associated with septic transfusion reactions may also be observed in the more common acute transfusion reactions; thus, laboratory testing is required to confirm suspicion of bacterial contamination. Septic transfusion reactions are more commonly associated with platelet transfusion than PRBC transfusion because of the presence of significant volumes of plasma and storage at room temperature of platelet products. Septic transfusion reactions may also be seen following transfusion of autologous blood products.
A PROGRAM TO INCREASE HEALTH CARE FOR CHILDREN: THE PEDIATRIC NURSE PRACTITIONER PROGRAM

The pediatric nurse practitioner program herein described is a new educational and training program in pediatrics for professional nurses which has been developed to provide increased health care for children in both rural and urban areas. The program prepares nurses to furnish comprehensive well child care to well children, to identify and appraise acute and chronic conditions, and to evaluate and temporarily manage emergency situations until medical assistance is available. The details of the educational and training program and its implications in improving the utilization of scientific manpower are described.
Characterization of Phage-Sensitive Mutants from a Phage-Insensitive Strain of Streptococcus lactis: Evidence for a Plasmid Determinant that Prevents Phage Adsorption.

A phage-insensitive strain of Streptococcus lactis, designated ME2, was used as a prototype strain for the study of mechanisms and genetics of phage resistance in the lactic streptococci. Mutants sensitive to a Streptococcus cremoris phage, varphi18, were isolated at a level of 17% from cultures of ME2 after sequential transfer at 30 degrees C. Phage-sensitive mutants of ME2 were not fully permissive to varphi18. The efficiency of plating of varphi18 on the mutants was 5 x 10 as compared with 99.8%, whereas ME2 adsorbed only 20 to 40% of varphi18. These results suggest that increased phage susceptibility of the mutants may result from the loss of a mechanism that inhibits phage adsorption. Moreover, the high frequency of spontaneous mutation in ME2 indicates the involvement of an unstable genetic determinant in this phage defense mechanism. ME2 was shown to possess 13 plasmids ranging in size from 1.6 to 34 megadaltons. Of 40 mutants examined that had increased efficiencies of plating, all were missing a 30-megadalton plasmid, pME0030. These data suggest that pME0030 codes for a function that prevents phage adsorption. Further phenotypic characterization of the phage-sensitive mutants showed that some mutants were deficient in the ability to ferment lactose (Lac) and hydrolyze milk proteins (Prt). However, the Lac and Prt phenotype segregated independently of the phage-sensitivity phenotype. One phage-sensitive adsorption mutant, designated N1, was tested for susceptibility to 14 different phages. N1 showed increased capacity to adsorb 4 and to replicate 2 of these 14 phages, thereby indicating a phage resistance mechanism in ME2 that generalizes to phage interactions other than the specific varphi18-ME2 phage-host interaction. These data provide evidence for a unique plasmid-linked phage defense mechanism in phage-insensitive strains of lactic streptococci.
"Frozen" Methane Escapes from the Sea Floor

The atmospheric concentrations of methane, a greenhouse gas, have been shown to increase in parallel with temperature increases in ice core records of glacial/interglacial cycles. Two different sources of this methane have been proposed: Methane hydrate stored in permafrost and on the sea floor, and bacterial processes in wetland environments. In this Perspective, Blunier discusses the implications of results reported by Kennett et al . of methane hydrate releases from the sea floor at times of rapid warming in the ice core records.
Suppression of murine experimental autoimmune encephalomyelitis by interleukin-2 receptor targeted fusion toxin, DAB389IL-2☆☆☆

Previously we have shown that DAB(389)IL-2, a recombinant fusion toxin targeting IL-2R bearing cells, suppressed disease in the rat experimental autoimmune encephalomyelitis (EAE) model of acute multiple sclerosis (MS). Our present study demonstrates that DAB(389)IL-2 can also effectively suppress acute (A)-EAE, relapsing (R)-EAE and chronic (C)-EAE in mouse demyelinating models. DAB(389)IL-2 significantly suppressed mitogenic proliferation of spleen cells while mutant fusion proteins DA(glu53)B(389)IL-2 and DAB(389)IL-2(8-10) did not. EAE was successfully suppressed when DAB(389)IL-2 was administered in various regimens between days 1 and 15 post immunization in all three models. CD4(+)IL-2R(+) cells were reduced in the spleen but not in the lymph nodes of DAB(389)IL-2-treated mice during A-EAE while the number of CD8(+) cells was unchanged. DAB(389)IL-2 also significantly reduced the number of CD4(+), CD8(+), CD25(+), TCRgammadelta(+) phenotype and CD11b(+) macrophages/microglia within spinal cord lesions. These data strongly suggest that DAB(389)IL-2 specifically targeted myelin protein-activated CD4(+) T cells and strengthens the argument for the use of DAB(389)IL-2 in treatment strategies for MS.
Dictyostelium myosin light chain kinase : purification and characterization

A Dictyostelium myosin light chain kinase has been purified approximately 15,000-fold to near homogeneity. The purified kinase is a single polypeptide of approximately 34 kDa that phosphorylates only the 18-kDa Dictyostelium myosin regulatory light chain and itself among substrates tested. The enzyme was purified largely by ammonium sulfate fractionation and hydrophobic (butyl) interaction chromatography. Analysis using polyclonal antibodies raised against the purified 34-kDa protein confirms that this protein is responsible for myosin light chain kinase activity. Protein microsequence of the 34-kDa protein reveals conserved protein kinase sequences. The purified Dictyostelium myosin light chain kinase exhibits a Km for Dictyostelium myosin of 4 microM and a Vmax of 8 nmol/min/mg. Unlike other characterized myosin light chain kinases, this enzyme is not regulated by calcium/calmodulin. Western blot analysis demonstrates that the purified kinase is not a proteolytic fragment that has lost calcium/calmodulin regulation. The Dictyostelium myosin light chain kinase activity is not directly regulated by cyclic nucleotides. However, this kinase undergoes an intramolecular autophosphorylation that activates the enzyme.
Benefit Cost Comparisons Between State and Local Governments and Private-Sector Employers

This paper examines some of the causes of the differences in total compensation costs between state and local government employers and private-sector employers. As of September of 2007, overall total compensation costs were 51.4 percent higher among state and local government employers ($39.50 per hour worked) than among private-sector employers ($26.09 per hour worked) (calculated from Figure 1). Total compensation costs consist of two major categories: wages and salaries and employee benefits. For both of these categories, state and local government employers' costs were higher than those of private-sector employers: 42.6 percent higher for wages and salaries and 72.8 percent higher for employee benefits (calculated from Figure 1). The differences in compensation costs between public-sector and private-sector employers are driven by the differing mix of job functions, work force composition, and concentrations of workers. The composition of the benefit package is another major factor in explaining the difference in compensation costs. Benefit participation rates are higher for state and local government employees and the costs of providing these benefits are higher. The PDF for the above title, published in the June 2008 issue of EBRI Notes, also contains the fulltext of another June 2008 EBRI Notes article abstracted on SSRN: "The Number of Individual Account Retirement Plans Owned by American Families."
Biosynthesis of Streptomycin III. ORIGIN OF THE CARBON ATOMS OF STREPTOSE

Abstract The pathway of synthesis by Streptomyces griseus of the streptose moiety of streptomycin from D-glucose has been studied. L-Serine-3-14C, D-glucose-l-14C, D-glucose-2-14C, D-glucose-3,4-14C, and D-glucose-6-14C were given to streptomycin-producing cultures. A 40 to 46% incorporation of 14C into the streptose moiety of the isolated streptomycin was found. Procedures for the total degradation of streptose were developed and utilized to determine the 14C-label pattern in this moiety. Examination of the isotope distribution data for the 6 carbons of streptose after administration of the above labeled compounds to the organism shows that streptose arises from a carbon-carbon rearrangement at carbon atoms 3 and 4 of glucose to form the branched sugar, streptose.
OBSERVATIONS OF INTENSE SUN GLINT IN THE DAYTIME MID-INFRARED MODIS CHANNELS-FEASIBILITY FOR SEA SURFACE TEMPERATURE RETRIEVALS

The affect of sun glint on the daytime mid infrared wavelengths of the MODerate-resolution Imaging Spectrometers (MODIS) data are explored. Differences of greater than 20C have been observed between the daytime thermal and mid infrared wavelengths sea surface temperature retrievals over the sun glint area. These differences can be attributed to daytime brightness temperature increases between the three bands in the MODIS mid infrared region over the sun glint area
Student performance: Assessment centers versus traditional classroom evaluation techniques

Abstract Assessment center (AC) scores were compared with traditional large-class evaluation techniques (i.e., multiple-choice exams, group project grades, and discussion section scores), grade point average, and intelligence test scores. Undergraduate business students (n = 347) were videotaped during an AC session consisting of an in-basket, two leaderless group discussions, and a speech. Trained raters used behavioral checklists to evaluate performance. AC scores correlated moderately with traditional evaluation techniques, suggesting that ACs measure knowledge acquisition in addition to skills acquired but not captured by traditional techniques. Their use is thus consistent with the emphasis on skill-based learning.
Analysis of Nitrosamines in Aqueous and Biological Fluids Based on Measurement of Photochemically Liberated Nitrite

A method is described for the analysis of nitrosamines in aqueous solution and in biological fluids (blood, plasma, and rat liver microsomal suspensions). The method is based on photochemical degradation of the nitrosamine in a controlled environment to yield the corresponding amine and nitrite ion, and the latter is subsequently used to form a chromophoric or fluorescent product. The analysis scheme is a modular three-component system consisting of a column to remove contaminating nitrite prior to photolysis, a photochemical reactor, and a chemical reactor. Additional modules are used to accommodate biological samples or large-volume (5--50 ml) aqueous samples. In this study, N-nitrosopyrrolidine, N-nitrosodimethylamine, and N,N-diethanolnitrosamine were utilized as substrates. Because of intersubstrate variability in the photochemical decomposition rate and overall nitrite yield, the structure (i.e., photochemical behavior) of the particular nitrosamine in the sample must be known prior to analysis. With a colorimetric readout, the sensitivity for analysis of N-nitrosopyrrolidine was 800 ng/ml for a 5-ml sample and the measurement precision was +/- 6% in the biological fluids. Fluorometric analysis improved sensitivity to 4 ng/ml with a precision of +/- 10% in biological media.
One-bond, two-bond, and three-bond mechanisms in thermal deazetizations of 2,3-diazabicyclo[2.2.2]oct-2-enes, trans-azomethane, and 2,3-diazabicyclo[2.2.1]hept-2-ene.

The thermal deazetizations of a series of substituted 2,3-diazabicyclo[2.2.2]oct-2-enes and some simpler model systems have been studied using the UB3LYP/6-31G(d) and CASPT2 methods, with a variety of active spaces. A fused cyclopropane exerts unique control on the mechanism and rate of deazetization. When the Walsh σ-orbitals are appropriately aligned in an exo orientation, a pericyclic three-bond cleavage occurs. For an endo-fused cyclopropane, sequential one-bond cleavages occur to take advantage of orbital overlap with the Walsh orbitals. In systems lacking strongly directing substituents, concerted two-bond cleavage pathways to form diradical intermediates have a small enthalpic advantage (ΔH0K⧧) over sequential one-bond cleavage pathways. However, the one-bond mechanism has an entropic advantage over the two-bond; consequently, at 400−500 K where decomposition occurs, one-bond and two-bond diradical cleavages both occur simultaneously. The thermal decompositions of trans-azomethane and 2,3-diazabicy...
Acute Encephalopathy Followed by Permanent Brain Injury or Death Associated With Further Attenuated Measles Vaccines: A Review of Claims Submitted to the National Vaccine Injury Compensation Program

Objective. To determine if there is evidence for a causal relationship between acute encephalopathy followed by permanent brain injury or death associated with the administration of further attenuated measles vaccines (Attenuvax or Lirugen, Hoechst Marion Roussel, Kansas City, MO), mumps vaccine (Mumpsvax, Merck and Co, Inc, West Point, PA), or rubella vaccines (Meruvax or Meruvax II, Merck and Co, Inc, West Point, PA), combined measles and rubella vaccine (M-R-Vax or M-R-Vax II, Merck and Co, Inc, West Point, PA), or combined measles, mumps, and rubella vaccine (M-M-R or M-M-R II, Merck and Co, Inc, West Point, PA), the lead author reviewed claims submitted to the National Vaccine Injury Compensation Program. Methods. The medical records of children who met the inclusion criteria of receiving the first dose of these vaccines between 1970 and 1993 and who developed such an encephalopathy with no determined cause within 15 days were identified and analyzed. Results. A total of 48 children, ages 10 to 49 months, met the inclusion criteria after receiving measles vaccine, alone or in combination. Eight children died, and the remainder had mental regression and retardation, chronic seizures, motor and sensory deficits, and movement disorders. The onset of neurologic signs or symptoms occurred with a nonrandom, statistically significant distribution of cases on days 8 and 9. No cases were identified after the administration of monovalent mumps or rubella vaccine. Conclusions. This clustering suggests that a causal relationship between measles vaccine and encephalopathy may exist as a rare complication of measles immunization.
Transtracheal pressure exerted by endotracheal tube cuffs.

Abstract Inflated endotracheal tubes may compress the tracheal mucosa causing ischemic tissue damage. In the present study, finite deformation analysis of the cuff was made assuming a rigid trachea. This solution provided transtracheal pressure as a fraction of the cuff inflation pressure. This ratio was examined at various degrees of contact between the cuff and trachea. Inflation pressure and contact pressures were obtained experimentally for endotracheal tubes inserted into rigid transparent cylinders about the size of tracheas. Using these data, it was possible to evaluate the estimates obtained from finite deformation analysis by comparing these estimates with experimentally-recorded data.
Measuring Trends in Segregation: Three Dimensions, Three Measures

Social scientists have tended to rely solely on the index of dissimilarity as a measure of segregation, without questioning what precise aspect of segregation is measured by this index. A recent paper by Lieberson and Carter has argued the merits of a less commonly used class of measures of pa interaction probabilities to tap an aspect of segregation not reflected by the index of dissimilarity. Standardizing these interaction probabilities by the proportion of minority/majority group members in the population yields yet a third class of measures, of which the best known is the correlation ratio or eta2. We argue that these three kinds of measures reflect conceptually distinct aspects of racial residential segregation. We analyze the relationships among the three and demonstrate with both simulated and real data that the results of empirical studies will depend on the measure chosen.
Hydrofluoric Acid in the Southern California Atmosphere

Atmospheric hydrofluoric acid concentrations were measured at nine sites in Southern California during an 8-month period. Long-term average HF concentrations measured by the tandem filter method ranged from 0.13 μg m^(-3) (0.15 ppb) at San Nicolas Island to 0.22 μg m^(-3) (0.25 ppb) onshore at Rubidoux, CA. The ambient concentration of HF shows little change throughout the year, with the notable exception of an occasional spike which approaches or exceeds 1 μg m^(-3) (1.12 ppb) over a 24-h averaging time. Due to the wide-ranging uses of HF in industry, and lacking natural sources to account for such spikes, it is possible that these spikes are due to accidental emissions from industrial sources, although no direct evidence of accidents on the dates involved was found.
Effect of graded hypothermia (27 degrees to 34 degrees C) on behavioral function, histopathology, and spinal blood flow after spinal ischemia in rat.

We used a rat model of reversible spinal ischemia to assess the effect of spinal cord temperature on the development of neurological and histopathologic changes after 20 minutes of reversible aortic occlusion. Spinal cord blood flow and CO2 reactivity was tested by using laser Doppler before and 60 minutes after ischemia.In halothane (1%)-anesthetized rats, the spinal cord temperature as assessed by using thermocouple in the paraspinal muscles was lowered to 34 degrees, 31 degrees, or 27 degrees C. After ischemia, spinal cord temperature was raised to 37 degrees C for the next 30 minutes. Animals were maintained in this normothermic condition for 8 hours, after which motor and sensory function were assessed. All animals were then anesthetized and perfused with 10% formalin for light microscopic analysis of spinal cords.In normothermic animals, 20 minutes of ischemia resulted in a loss of CO2 reactivity and hind limb paraplegia with an attendant allodynia that persisted for the 8 hours of reperfusion. Even...
Anthropology, development and public policy

The PDF of this file is 4,458 kbytes in size and therefore will take a long time to download if you click on the PDF link below. If you would like the file to be sent to you by email, please send a request to info@nepjol.info. Please include the citation below in your request. DOI: 10.3126/opsa.v4i0.1083 Occasional Papers in Sociology and Anthropology Vol.4 1994 p.3-32
Maternal distress, child behaviour, and disclosure of psychosocial concerns to a paediatrician.

Background Despite the availability of effective screening measures, primary care providers continue to fail to identify and manage many children with psychosocial problems. One of the best predictors of identification by a primary care physician is whether mothers disclose concerns about their child's psychosocial functioning to their child's physician. This study examined if maternal distress and child behaviour predicted whether mothers had and discussed concerns about their child's behaviour and emotions with paediatricians. Methods Participants were 138 mothers who accompanied their 4–12-year-old children to a health supervision visit at an urban teaching hospital. Mothers completed a demographic questionnaire, the Pediatric Symptom Checklist, the Beck Depression Inventory, and an exit questionnaire. Results Logistic regression correctly classified 97.3% of mothers who did not disclose child problems. Only 34.5% of mothers who did disclose were correctly classified. Conclusions The results supported the hypothesis that mothers’ psychosocial functioning is significantly related to concern about child behaviour and disclosure of concerns to the paediatrician. The inability of child behaviour and maternal functioning to predict which mothers were concerned and disclosed concerns supports the hypothesis that disclosure and identification of psychosocial problems in primary care is complex and requires a multifactor model.
Numerical studies of left handed metamaterials: Abstract

We use the three dimensional Finite Difference Time Domain (FDTD) technique to study metamaterials exhibiting both negative permittivity and permeability in certain frequency bands. The structure under study is the well-known periodic arrangement of rods and split-ring resonators, previously used in experimental setups. The three parameters we study are the transmission coefficient of a slab, the phase variation of the propagating fields within the metamaterial, and the refraction of a wave through a prism. To our knowledge, this is the first time that the last two parameters are studied rigorously using a numerical method. The results of this work show that fields propagating inside the metamaterial with a forward power direction exhibit a backward phase velocity and negative index of refraction.
Patients' Perceptions Compared with Objective Ratings of Asthma Severity

Background Optimal asthma management requires accurate assessment of asthma severity. Objective To compare patients' perceptions of their asthma severity with that obtained by using the guidelines published by the National Asthma Education and Prevention Program's Expert Panel and with functional impairment measured by spirometry and numeric criteria of the American Thoracic Society. Methods We enrolled 323 patients aged 18 to 50 years who were members of the Kaiser Foundation Health Plan for ≥ 1 year in a randomized control trial of an asthma education program. Each had a confirmed diagnosis of bronchial asthma and had been receiving antiasthma medication for ≥ 1 year. Patients rated the severity of their asthma. Office spirometry was performed, and, using the Mini-Wright peak flow meter, patients kept 2-week diaries of at-home recordings of morning and evening peak expiratory flow rates. Results A statistically significant association was noted between patients' perceptions of asthma severity and both medication severity rating (P P = .003) and evening peak expiratory flow rate percentage (P = .019). In comparison to a severity composite based on criteria of the National Asthma Education Program, 54% of patients accurately estimated asthma severity, 27% overestimated, and 20% underestimated severity. Conclusion A clinically significant proportion of asthmatic patients substantially underestimate disease severity and thereby may be at risk of increased mortality or morbidity.
Female preference and the evolution of an exaggerated male ornament: the shape of the preference function matters

Sexual selection theory often predicts that female preferences will produce directional selection for male traits that either reinforces or opposes male–male competition. However, without considering the complexity of preference functions and the potential for adaptive variation in female mate preferences, the direction of selection due to female preference can be misidentified. Previous studies have suggested that female preference opposed male–male competition in the evolution of the large, sexually dimorphic dorsal fin in the swordtail fish, Xiphophorus birchmanni. We present two lines of evidence to suggest that female preference selects for enlarged dorsal fins in male X. birchmanni, and therefore female preferences are not directional for small dorsal fins, but instead are potentially disruptive. Xiphophorus birchmanni females prefer dorsal fins that are larger than expected given the male’s size, and during male–female interactions, males raise their dorsal fins as part of their courtship display directed towards females. We argue that selection due to female preference is likely to be much more complex than is often considered.
A review of residual stresses and tensioning in circular saws

The origin and measurement of residual stresses and their effect on the transverse stability of circular saws are discussed, with emphasis placed on nondestructive stress analyses, their limits of application, and their possible adaptation to the measurement of residual stresses in circular saws. Saw stability variations can be computed once the stress distribution is known. Evaluation of the X-ray diffraction technique and the ultrasonic and magnetic methods were considered for this purpose.
Sum rules for forward elastic photon scattering

Abstract Relations between integrals over forward elastic photon scattering amplitudes, forward elastic cross sections and total cross sections are derived from dispersion relations. A new photon-proton interaction sum rule is derived and evaluated.
Parental Divorce and College Students: The Impact of Family Unpredictability and Perceptions of Divorce

The impact of parental divorce, perceptions of divorce, and family unpredictability on the locus of control, interpersonal trust, and assertiveness of college students (n = 115) was studied. Roughly 27% of participants came from divorced homes; they did not differ significantly from participants from nondivorced homes on locus of control, trust, or assertiveness. However, negative perceptions of parental divorce were associated with a more external locus of control. Aspects of maternal unpredictability related to lower trust yet higher assertiveness. Participants with divorced parents reported more unpredictable finances and somewhat more unpredictable meals growing up. Implications for adjusting to divorce are discussed.
CSPs and Connectedness: P/NP Dichotomy for Idempotent, Right Quasigroups

In the 1990's, Jeavons showed that every finite algebra corresponds to a class of constraint satisfaction problems. Vardi later conjectured that idempotent algebras exhibit P/NP dichotomy: Every non NP-complete algebra in this class must be tractable. Here we discuss how tractability corresponds to connectivity in Cayley graphs. In particular, we show that dichotomy in finite idempotent, right quasi groups follows from a very strong notion of connectivity. Moreover, P/NP membership is first-order axiomatizable in involutory quandles.
Shiga toxin (Stx)1B and Stx2B induce von Willebrand factor secretion from human umbilical vein endothelial cells through different signaling pathways

Diarrhea-associated hemolytic uremic syndrome (D+HUS) is caused by the ingestion of Escherichia coli that produce Shiga toxin (Stx), which is composed of a cytotoxic A subunit and pentameric B subunits that bind globotriaosylceramide on susceptible cells. Stx occurs in 2 types, Stx1 and Stx2. B subunits of either type stimulate von Willebrand factor (VWF) secretion from human umbilical vein endothelial cells (HUVECs), and Stx2B can cause thrombotic microangiopathy in Adamts13−/− mice. We have now determined that Stx1B and Stx2B activate different signaling pathways in HUVECs. VWF secretion induced by Stx1B is associated with a transient rise in intracellular Ca2+ level that is blocked by chelation with 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid-acetoxymethyl ester, removal of extracellular Ca2+, the phospholipase C inhibitor U73122, the protein kinase inhibitor staurosporine, or small interfering RNA knockdown of protein kinase Cα. In contrast, Stx2B-induced VWF secretion is associated with activation of protein kinase A (PKA) and is blocked by the PKA inhibitor H89 or small interfering RNA knockdown of PKA. Stx2B does not increase cAMP levels and may activate PKA by a cAMP-independent mechanism. The activation of distinct signaling pathways may be relevant to understanding why E coli that express Stx2 are more likely to cause D+HUS than are E coli expressing only Stx1.
Geochemical and hydrologic controls on the composition of surface water in a high‐elevation basin. Sierra Nevada, California

Hydrologic, mineralogic, and soil data are used to determine the sources and geochemical controls on the composition of surface water in the Emerald Lake watershed (ELW), a high-altitude basin located in the southern Sierra Nevada. The solute composition of stream waters at the ELW can be divided into three periods: snowpack runoff, a transition period in summer as snowpack runoff decreases and little precipitation occurs, and a low-flow period from late summer through winter. Each period has different geochemical controls on the solute composition of surface waters. During snowpack runoff -50% of stream flow was from direct surface runoff and -50% of stream flow was return flow from subsurface reservoirs. Hydrologic residence time of subsurface water at maximum snowpack runoff was measured directly with a 6LiBr tracer and varied from 9 to 20 h. Three independent measurements show that the acidity in snowpack runoff was neutralized by cation exchange in soils and talus. Discharge from soil reservoirs was the primary source of stream flow during the summer transition period when the composition of stream flow was congruent with the stoichiometry of plagioclase weathering. Processes occurring below the soil zone exerted the dominant geochemical controls on the composition of stream waters during the period of low flow, with preferential weathering of the anorthite component of plagioclase in subsurface rock and further weathering of kaolinite to gibbsite.
Masking of tones by tones and of noise by noise

Using a two-alternative temporal forced-choice technique, two binaural detection experiments were performed. In the first, the detectability of a 250-Hz 128-msec tonal signal masked by a gated 70-dB SPL tone of the same frequency and duration was measured as a function of the level of the signal, the phase angle at which the signal was added to the masker, and the interaural phase difference of the signal. In the second experiment, the signal was a wideband (100-3,000 Hz) 128-msec Gaussian noise masked by a continuous Gaussian noise of the same bandwidth and coherent with the signal. The detectability of this noise signal was measured as a function of the same variables investigated in the first experiment. In both experiments detectability was found to follow a simple energy- or power-detection model when the interaural phase difference was 0 deg. When the interaural phase difference was 180 deg, the function relating the signal level required for a constant level of performance to the signal-masker phase angle is such that neither the Webster-Jeffress hypothesis nor Durlach’s E-C model accounts for the data. The data are reasonably well fit by a model proposed by Hafter and Carrier.
Performance Evaluation of Federal Administrative Law Judges: Challenge for Public Administration?

Federal administrative law judges (ALJs) are among the few classified service employees who are exempted from periodic performance review. The purpose is to protect their decisional independence from encroachment by the agencies that employ them. Given the interest of the public administration community in performance evaluation, this article reviews and analyzes recent attempts to answer the question of who should evaluate federal ALJs' performance. The end in view is to challenge the community in general and human resources scholars and practitioners in particular to add the question posed here to their purview. The importance of the ALJ position and the difficulty of answering the question deserve a wider, informed audience.
Exposure strategies for polymethyl methacrylate from in situ x-ray absorption near edge structure spectroscopy

We have observed the chemical changes in PMMA irradiated by x rays in situ. The chemical changes are monitored by micro‐x‐ray absorption near edge structure spectra at the carbon absorption edge. The loss of the ester group (C=O) and formation of C=C bonds have been determined quantitatively from changes in the intensities of the respective π* resonant peaks as a function of dose. Samples prepared under different conditions were examined. From the dose dependence of bond formation, scission and linking, the performance of the resist can be predicted, so that the preparation strategy, dose, and development can be optimized.
A test of space-time arma modelling and forecasting of hotel data

This paper describes the application of space-time ARMA modelling to demand-related data from eight hotels from a single hotel chain in a large US city. Important spatial characteristics of the space-time process are incorporated into the model using a simple weighting matrix based on driving distances between the hotels. Using a hold-out sample, the forecasting performance of this space-time approach was found to be superior to eight separate univariate ARMA models.
Continuous Dye-Machine Control

Automatic controlling of process and machine variables to obtain high production efficiency is discussed. The high-speed machinery used in processing presents a major problem if not properly controlled and is dramatically reflected in profits of the operation. One textile process involving the complexity of machine and process variables is described.
Monopolistic Competition in the Spirit of Chamberlin: A General Model

This paper develops a model of "large group" Chamberlinian monopolistic competition in which (1) there are many firms producing differentiated commodities, (2) each firm is negligible in that it can ignore its impact on, and hence reactions from, other firms; (3) free entry leads to zero profit of operating firms; but (4) each firm faces a downward-sloping demand curve. The existence of a monopolistically competitive equilibrium is established. In a companion paper, more particular questions such as whether the market provides too many or too few products are addressed for a special case of the model.
Hypothalamic effects on spinal reflexes and their alteration by pentobarbital

Abstract The effects of hypothalamic stimulation on spinal cord reflexes were investigated in intact, immobilized cats and in animals under different levels of pentobarbital anesthesia. Concurrently, potentials evoked in the hypothalamus upon peripheral stimulation were studied. In immobilized and in lightly anesthetized animals, high-frequency hypothalamic stimulation usually potentiated monosynaptic and depressed polysynaptic reflexes. The effect on the former was much more consistent and reliable. In these animals peripheral nerve stimulation evoked potentials in the hypothalamus of 20- to 40-msec latency. Moderate pentobarbital anesthesia caused the diminution of hypothalamic effects on spinal cord reflexes, and the disappearance of the peripherally evoked potentials in the hypothalamus. Deepening of anesthesia abolished hypothalamic facilitation of the spinal monosynaptic reflex. Hypothalamic stimulation had little or no effect on the polysynaptic response in those animals in which it persisted. At this stage of deep anesthesia, high-voltage secondary long latency (60–160 msec) potentials were evoked in the hypothalamus upon peripheral nerve stimulation. Although the effect of anesthesia on the spinal mechanisms may account for part of the observed results, the data indicate that the effects noted are due primarily to the actions of pentobarbital in the hypothalamus. It is postulated that in the lightly anesthetized or immobilized intact animal the facilitatory brain-stem regions have a predominant effect on spinal cord reflexes, and that anesthesia (or decerebration) attenuates this facilitatory effect, thus allowing inhibitory effect of the bulbar reticular formation on the spinal cord to be shown.
A new method for generating canopy height models from discrete-return LiDAR point clouds

Tree height underestimation and occurrence of visible data pits are two major problems in light detection and ranging (LiDAR)-derived digital surface models and canopy height models (CHMs) in forested areas. To address the two major problems, a new method is proposed for generating CHMs from discrete-return LiDAR point clouds using a selecting and sorting mechanism based on a circle centred at the target point, followed by spatial interpolation. Test results from simulated and real LiDAR point clouds show that the new method outperformed three other methods in terms of treetop approximation, crown surface representation and data pit removal.
On ↗-normal spaces

Abstract A separarion property called ↗-normal and weaker than normality is investigated. The main results include: Under V = L , a first countable ↗-normal space is σ-collectionwise Hausdorff, and in a locally compact ↗-normal space any discrete collection D of compact sets with | D | ω1 can be σ-separated. Under PMEA, a first countable ↗-normal space is collectionwise ↗-normal. Any countably paracompact ↗-normal space X is normal and any countably metacompact, normal ↗-cwN space is cwN.
Characterization and compilation of polymorphic simple sequence repeat (SSR) markers of peanut from public database

There are several reports describing thousands of SSR markers in the peanut (Arachis hypogaea L.) genome. There is a need to integrate various research reports of peanut DNA polymorphism into a single platform. Further, because of lack of uniformity in the labeling of these markers across the publications, there is some confusion on the identities of many markers. We describe below an effort to develop a central comprehensive database of polymorphic SSR markers in peanut. We compiled 1,343 SSR markers as detecting polymorphism (14.5%) within a total of 9,274 markers. Amongst all polymorphic SSRs examined, we found that AG motif (36.5%) was the most abundant followed by AAG (12.1%), AAT (10.9%), and AT (10.3%).The mean length of SSR repeats in dinucleotide SSRs was significantly longer than that in trinucleotide SSRs. Dinucleotide SSRs showed higher polymorphism frequency for genomic SSRs when compared to trinucleotide SSRs, while for EST-SSRs, the frequency of polymorphic SSRs was higher in trinucleotide SSRs than in dinucleotide SSRs. The correlation of the length of SSR and the frequency of polymorphism revealed that the frequency of polymorphism was decreased as motif repeat number increased. The assembled polymorphic SSRs would enhance the density of the existing genetic maps of peanut, which could also be a useful source of DNA markers suitable for high-throughput QTL mapping and marker-assisted selection in peanut improvement and thus would be of value to breeders.
Future directions in aeronautical research and technology

The aeronautical R & D effort in NASA is discussed with emphasis on those areas where major needs and opportunities exist. In aerodynamics, areas selected for discussion include computational aerodynamics, transonic test techniques, high Reynolds number research, skin friction drag reduction, and propulsive lift. In propulsion, consideration is given to the areas of fuel-efficient subsonic propulsion, variable-flow engines, hypersonic propulsion, alternate fuels, and aircraft noise reduction. Consideration is also given to the utilization of advanced composites and integrated avionic systems.
The McCarthy Scales of Children's Abilities as a Predictor of Achievement: A Five-Year Follow-Up.

The purpose of the present study was to determine if the McCarthy Scales of Children's Abilities could be utilized as a predictor of achievement over a six-year period. Twenty-four kindergarten children were tested with the McCarthy Scales and subsequently examined with the Comprehensive Testing Program achievement tests in sixth grade. A correlational analysis of the data resulted in significant relationships between the McCarthy General Cognitive Index, Quantitative Scale, and Memory Scale and both the CTP and course grades. The McCarthy Perceptual-Performance Scale showed significant correlations with the CTP but not with course grades; the Verbal Scale was not predictive of academic achievement. The significance of these findings is discussed.