cssi/SciSciGPT-SciSciNet huggingface dataset:
Retrospective IMRT dose reconstruction based on cone-beam CT and MLC log-file.

Purpose Head-and-neck (HN) cone-beam computed tomography (CBCT) can be exploited to probe the IMRT dose delivered to a patient taking into account the interfraction anatomic variation and any potential inaccuracy in the IMRT delivery. The aim of this work is to reconstruct the intensity-modulated radiation therapy dose delivered to an HN patient using the CBCT and multileaf collimator (MLC) log-files. Methods and Materials A cylindrical CT phantom was used for calibrating the electron density and validating the procedures of the dose reconstruction. Five HN patients were chosen, and for each patient, CBCTs were performed on three separate fractions spaced every 2 weeks starting from the first fraction. The respective MLC log-files were retrieved and converted into fluence maps. The dose was then reconstructed on the corresponding CBCT with the regenerated fluence maps. The reconstructed dose distribution, dosimetric endpoints, and DVHs were compared with that of the treatment plan. Results Phantom study showed that HN CBCT can be directly used for dose reconstruction. For most treatment sessions, the CBCT-based dose reconstructions yielded DVHs of the targets close (within 3%) to that of the original treatment plans. However, dosimetric changes (within 10%) due to anatomic variations caused by setup inaccuracy, organ deformation, tumour shrinkage, or weight loss (or a combination of these) were observed for the critical organs. Conclusions The methodology we established affords an objective dosimetric basis for the clinical decision on whether a replanning is necessary during the course of treatment and provides a valuable platform for adaptive therapy in future.
Hypothermia: its possible role in cardiac surgery.

Abstract The current safety of operations on the heart requiring cardiopulmonary bypass occurred because of a series of step-by-step laboratory and clinical investigations that were compromises between the time needed for heart repair and the brain's requirement for oxygen. The first step, so clearly shown in a paper by Bigelow and associates in 1950, was the reduction of the brain's need for oxygen by surface cooling to 28 ° to 32 °C, limited to this level by cardiac and pulmonary failure at levels lower than this. The six to eight minutes of circulatory arrest permitted time for repair of simple defects. This method was rapidly adopted by many surgeons. As low-flow pump oxygenators became available, blood cooling to 10 ° to 20 °C was introduced. This increased the periods of circulatory arrest to 30 to 60 minutes, and also made still longer periods of bypass with the pump oxygenator possible. Hypothermia to reduce oxygen and metabolic requirements is still an important adjunct to bypass, even with the currently used efficient pump oxygenators. It remains the most important component of mycardial preservation, and has made possible the delay needed for transportation between the harvesting and the transplantation of organs.
Community-phenotype-methicillin-resistant Staphylococcus aureus infections: a retrospective chart review of outcomes after treatment with daptomycin.

Abstract Background: Daptomycin, a cyclic lipopeptide antibiotic, was approved by the US Food and Drug Administration (FDA) in September 2003 for the treatment of complicated skin and skin structure infections due to susceptible strains of certain gram-positive microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA). In May 2006, daptomycin was approved by the FDA for treatment of bacteremia and right-sided endocarditis due to MRSA and methicillin-sensitive S aureus . Objective: The aim of this study was to assess the use of daptomycin in community-phenotype (CP)-MRSA infections. Methods: This was a retrospective chart review of data from patients enrolled in a postlabeling registry who received daptomycin for MRSA infections from January to December 2005. CP-MRSA was defined as MRSA susceptible to clindamycin and trimethoprim/sulfamethoxazole; all other phenotypes were considered other-phenotype MRSA ( OP-MRSA ). Success rates were calculated by dividing success (defined as cure plus improved) by success and failure (including non-evaluable patients). Results: A database search identified 352 patients (100 patients with CP-MRSA [57 men; 43 women]; 252 patients with OP-MRSA [136 men, 116 women]) who met study criteria. Most patients (79.2%) received gram-positive antibiotics before daptomycin. Compared with OP-MRSA, a greater proportion of patients with CP-MRSA were P Conclusion: Daptomycin was found to be equally effective in treating CP-MRSA and OP-MRSA infections in this selected group of patients.
Study of Some Trapped Hole Centers in X‐Irradiated Alkali Silicate Glasses

A detailed study has been made of the EPR spectra of trapped hole centers formed by x irradiation in alkali silicate glasses. The spectra of the five alkali silicate glasses were studied as a function of composition, microwave power, and bleaching temperature. It was found that the spectra could be decomposed into two separate hole spectra. The intensity ratio of these two spectra depends on the alkali‐to‐silica ratio. The center more abundant in the low‐alkali silicate glasses is called Hole Center 1, HC1; the center more abundant in the high‐alkali silicate glasses is called HC2. Helpful in separating the two spectra was a dual cavity technique, which makes it possible to obtain sum and difference spectra. The spectra of both centers are fundamentally the same in all alkali silicate glasses, but differences in detail are shown to be due to a relatively small interaction with neighboring alkali ions. Both centers show a distribution in the thermal stability and associated spectral parameters. The propose...
Outcome in children with symptomatic congenital cytomegalovirus infection.

To determine factors that are associated with adverse developmental outcome after congenital cytomegalovirus infection, we reviewed the clinical, laboratory, and radiographic findings in 18 childre...
Fetal mesenchymal hamartoma of kidney. A tumor of secondary mesenchyme

The ultrastructure of a fetal mesenchymal hamartoma of the kidney shows undifferentiated mesenchymal cells, whose morphological characteristics conform to those of secondary mesenchyme. In contrast to primary mesenchyme or mesoblast, which may form epithelial structures, secondary mesenchyme is incapable of doing so. While Wilms' tumor may be considered a tumor of mesoblast, the fetal mesenchymal hamartoma is believed to originate from secondary mesenchyme or some of its more mature derivatives.
Circumventing the Mechanochemical Origins of Strength Loss in the Synthesis of Hierarchical Carbon Fibers

Hierarchical carbon fibers (CFs) sheathed with radial arrays of carbon nanotubes (CNTs) are promising candidates for improving the intra- and interlaminar properties of advanced fiber-reinforced composites (e.g., graphite/epoxy) and for high-surface-area electrodes for battery and supercapacitor architectures. While CVD growth of CNTs on CFs has been previously shown to improve the apparent shear strength between fibers and polymer matrices (up to 60%), this has to date been achieved only at the expense of significant reductions in tensile strength (∼30–50%) and stiffness (∼10–20%) of the underlying fiber. Here we demonstrate two approaches for growing aligned and unaligned CNTs on CFs that enable preservation of fiber strength and stiffness. We observe that CVD-induced reduction of fiber strength and stiffness is primarily attributable to mechanochemical reorganization of the underlying fiber when heated untensioned above ∼550 °C in both hydrocarbon-containing and inert atmospheres. We show that tensioni...
The subcellular organization of neocortical excitatory connections

The mapping of neuronal connections in the cerebral cortex has traditionally relied on electrophysiological recordings performed on brain slices, in which long-range connections are severed. Karel Svoboda and colleagues have now adapted a recent optogenetic method to map long-range inputs onto various segments of the dendritic arbours of cortical pyramidal neurons. They find that specific inputs tend to cluster in distinct domains within dendritic trees. Such spatial segregation of different axonal inputs within dendrites may strengthen coupling of coherent cell populations during neuronal information processing and learning. A recent optogenetic method has been adapted to map long-range inputs onto various segments of the dendritic arborizations of cortical pyramidal neurons. Specific inputs tend to cluster in distinct domains within dendritic trees. Such spatial segregation of different axonal inputs within dendrites may strengthen coupling of coherent cell populations during neuronal information processing and learning. Understanding cortical circuits will require mapping the connections between specific populations of neurons1, as well as determining the dendritic locations where the synapses occur2. The dendrites of individual cortical neurons overlap with numerous types of local and long-range excitatory axons, but axodendritic overlap is not always a good predictor of actual connection strength3,4,5. Here we developed an efficient channelrhodopsin-2 (ChR2)-assisted method6,7,8 to map the spatial distribution of synaptic inputs, defined by presynaptic ChR2 expression, within the dendritic arborizations of recorded neurons. We expressed ChR2 in two thalamic nuclei, the whisker motor cortex and local excitatory neurons and mapped their synapses with pyramidal neurons in layers 3, 5A and 5B (L3, L5A and L5B) in the mouse barrel cortex. Within the dendritic arborizations of L3 cells, individual inputs impinged onto distinct single domains. These domains were arrayed in an orderly, monotonic pattern along the apical axis: axons from more central origins targeted progressively higher regions of the apical dendrites. In L5 arborizations, different inputs targeted separate basal and apical domains. Input to L3 and L5 dendrites in L1 was related to whisker movement and position, suggesting that these signals have a role in controlling the gain of their target neurons9. Our experiments reveal high specificity in the subcellular organization of excitatory circuits.
Plasmodium sasai n. sp. from the Japanese Lizard Takydromus tachydromoides

SYNOPSIS. This is the 1st reptilian Plasmodium to be described from eastern Asia. It is apparently of limited geographic distribution. Experimental infections may result in the production of more parasites than red cells in the circulating blood. A single erythrocyte may be infected by as many as 11 parasites. Despite the heavy parasitemia and destruction of erythrocytes, the hosts are apparently not affected by the infection. Mature schizonts are frequently fan-shaped; they produce 7–17 merozoites. The asexual cycle has a high degree of synchrony.
The Aspergillus Genome Database, a curated comparative genomics resource for gene, protein and sequence information for the Aspergillus research community

The Aspergillus Genome Database (AspGD) is an online genomics resource for researchers studying the genetics and molecular biology of the Aspergilli. AspGD combines high-quality manual curation of the experimental scientific literature examining the genetics and molecular biology of Aspergilli, cutting-edge comparative genomics approaches to iteratively refine and improve structural gene annotations across multiple Aspergillus species, and web-based research tools for accessing and exploring the data. All of these data are freely available at http://www.aspgd.org. We welcome feedback from users and the research community at ude.drofnats.emoneg@rotaruc-sulligrepsa.
Neuroscience: A social hub for worms.

There are more connections in the human brain than there are stars in the Milky Way, so scientists use simple organisms to search for universal neural-circuit motifs. Their latest find is a neuron for social behaviour.
Mental health and the quiet campus

An investigation of the social correlates of mild emotional disturbance, specifically anxiety and depressed mood, was conducted among a sample of full-time undergraduates (N=214) at a liberal arts college which had been free of social disorder for some time. Results of the study indicated the presence of strikingly high levels of both mood disturbances among the outwardly calm student body. These mood disorders were strongly correlated with negative attitudes toward the college. And contrary to alienation theory, negative attitudes were not decreased in those who participated in college activities. Students who were more closely integrated into college life, particularly residentially, were those with the most negative attitudes and the highest reported stress reactions to college. Consideration of the college as a “total institution” may help to explain these findings.
Pervious Concrete Surface Characterization to Reduce Slip-Related Falls

This paper presents results from a unique study that employed biomechanical evaluation techniques to assess the slipping behavior of traditional and pervious concrete pavements under icy conditions. Gait motion analysis using embedded force plates, electromyography, and tracking videography were used to analyze subject mobility of on icy and wet pervious concrete. Results show that pedestrian contact pressure on pervious concrete is more than twice the pressure on traditional impervious concrete. In slippery conditions, the pervious concrete specimens had more controlled gait cycles and reduced slipping. The unique surface characteristics combined with high permeability reduces surface icing, suggesting that pervious concrete offers superior slip resistance in inclement weather.
Sensing Side Effects for Supplementary Checkout Data

In working with checkout equipments for weapon systems, it becomes apparent that a new approach to solving the problems of status testing, fault isolation, and failure prediction is required. The approach which this paper proposes is to effectively utilize the side effects which have bothered the system designers in the past. This paper points out that the relative advantages of this approach outweigh the disadvantages. It shows that there are a number of effects available for use but that research and development efforts on detectors and interpretation techniques are required. This paper further suggests that these techniques can be applied to the checkout of mechanical and electromechanical systems.
Fate of fluorescent core-shell silica nanoparticles during simulated secondary wastewater treatment

Increasing use of silica nanoparticles (SiO2 NPs) in consumer products and industrial processes leads to SiO2 NP discharge into wastewater. Thus, there is a need to understand the fate of SiO2 NPs during wastewater treatment. However, the detection of SiO2 NPs in environmental systems is hindered by the elevated background levels of natural silicon. In this work, laboratory-synthesized fluorescent core-shell SiO2 NPs were used to study the fate of these NPs during secondary wastewater treatment. Fluorescent measurements provided an easy and fast method for SiO2 NP tracking. A laboratory-scale activated sludge system consisting of an aeration tank and a settler was fed with synthetic wastewater containing ca. 7.5 mg L(-1) of fluorescent SiO2 NPs for 30 days. SiO2 NPs were effectively removed from the wastewater (>96%) during the first 6 days, however the concentration of SiO2 NPs in the effluent gradually increased afterwards and the NP discharge was as high as 65% of the input after 30 days of NP dosing. The poor removal of the SiO2 NPs was related to the high colloidal stability of the NPs in the wastewater and their limited propensity to biosorption. Although some degree of NP adsorption on the biomass was observed using fluorescence microscopy, the affinity of SiO2 NPs for the activated sludge was not enough for a sustained and effective removal of the SiO2 NPs from the wastewater.
Immunochemical characterization of variant medium-chain acyl-CoA dehydrogenase in fibroblasts from patients with medium-chain acyl-CoA dehydrogenase deficiency.

ABSTRACT: Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is a common autosomal recessive disorder of mitochondrial fatty acid oxidation characterized by episodes of hypoketotic hypoglycemia usually beginning in the first 2 y of life. We previously showed, in pulse labeling experiments, that the biosynthesis and immediate posttranslational processing of MCAD are normal in fibro-blasts from patients with MCAD deficiency. Most patients studied to date are homozygous for a point mutation (A985-G) that results in the substitution of glutamate for lysine at residue 304 of the mature MCAD subunit. We performed immunoblot analysis of fibroblast MCAD from a total of 34 patients with MCAD deficiency, including 31 homozygous for the A985-G mutation, using a rabbit anti-rat MCAD antibody that cross-reacted specifically with human MCAD, but not with the related enzymes, short-chain and long-chain acyl-CoA dehydrogenases. All patients with the A985-G mutation lacked detectable MCAD. Pulse-chase labeling of MCAD-deficient fibroblasts with 35S-methionine demonstrated that this variant MCAD was unstable compared to controls. Taken together, these data suggest that this mutation affects the stability of MCAD protein within the mitochondrial matrix.
How responsive is U.S. population growth to immigration? A situational sensitivity analysis

There has been public concern about the effect of immigration on population growth in the U.S. But how responsive is population growth to immigration? This paper examines the sensitivity of intrinsic population growth to immigration and situates such sensitivity in fertility and survival changes. The application of second derivatives on a modified Leslie matrix facilitates the analysis of situational sensitivity of U.S. population growth to immigration. The results show that the sensitivity to immigration is not as influential as the sensitivity to fertility, and that the sensitivity to immigration further depends on changes in fertility and survival.
Serological evidence for the alteration of enolase during aging.

Abstract Pure enolase isolated from young and old Turbatrix aceti has been compared using immunological techniques. Antiserum prepared to “young” and “old” enolase, respectively, will completely precipitate either enzyme. However, antiserum prepared to “young” enolase reacts more efficiently with “young” than with “old” enzyme and vice versa. A third form of enolase (inactive enolase) is found in homogenates of old organisms. This material yields a pattern of identity with “young” enolase and partial identity with “old” enolase. It also gives rise to specific antibodies which do not react with “young” or “old” enolase. The material appears to accumulate with age. The results indicate a close structural relationship between “young”, “old” and inactive enolase.
Controversies in neonatal nutrition: docosahexanoic acid (DHA) and nucleotides

The breast-fed infant is the gold standard for infant formula research and development. The addition of long-chain polyunsaturated fatty acids and nucleotides to formula are intended to promote visual, neuro and immune development. Studies in both preterm and term infants have not consistently demonstrated efficacy with long-chain polyunsaturated fatty acids supplementation of infant formulas. Explanations for why these supplemented formulas do not always produce visual or neurodevelopmental advantages, include a small individual effect or that only a proportion of infants will benefit or the presence of confounding variables. The efficacy of nucleotides has been studied by analyzing response to vaccination in infants fed human milk versus formulas with or without additional nucleotides. Nucleotide supplemented formulas appear to enhance immune response similar to breast-fed infants with immunization. Humanizing formula with safe and well-studied nutrients may provide benefits that are discovered long after initial trials are concluded.
Structural Analysis of Nuclear Genes Coding for the Precursor to the Small Subunit of Wheat Ribulose–1,5–Bisphosphate Carboxylase

We have isolated and characterized a full–length cDNA clone encoding the precursor to the small subunit of wheat ribulose–1,5–bisphosphate carboxylase. From the nucleotide sequence, we deduce that the precursor contains the mature small subunit of 128 amino acid residues and an amino–terminal transit sequence of 47 amino acid residues. Southern blot analysis reveals that the small subunit precursor is encoded by a multigene family. One member of the family has been isolated. Nucleotide sequence and R–loop analyses show that it contains only one intron which separates the coding sequence of the transit peptide from that of the mature protein. This gene is expressed in vivo, as shown by mRNA hybridization to a specific probe from its 3′ non–coding region.
AIMS AND METHODS IN CHILD PSYCHOTHERAPY.

Child psychotherapy appears to be a theoretical orphan. Both adult psychotherapy and child analysis have a parent in classic psychoanalysis. The relation between these therapeutic methods and child psychotherapy has rarely been described in the literature beyond brief mention and a declared preference for child analysis in the treatment of severe emotional disturbances of childhood, despite the greater practical difficulties and the special training it requires. I know of only one short paper (Arthur, 1952) which compares child psychotherapy and child analysis. At present, the term child psychotherapy includes diverse methods of treatment (interpretive therapy, play therapy, release therapy, guidance, counseling, remedial education, and the group therapies) and seems to serve as a loose name for the many forms of treatment of children other than analysis. It is not yet a name for exclusively defined and related therapeutic techniques. Numberless contributions from psychiatry and allied fields deal with aspects of theory and practice in child psychotherapy; those based upon psychoanalysis are usually the most theoretically complete.' Often authors do not state,
Suggested treatment protocol for improving patency of femoral-infrapopliteal cryopreserved saphenous vein allografts.

Abstract Purpose: Cryopreserved saphenous vein allografts are used for femoral-infrapopliteal bypass graft purposes when adequate autogenous vein is unavailable. Anticoagulation, immunosuppression therapy, or both have been suggested means for improving allograft patency. Immunosuppression has significant cost and morbidity and has produced variable results. Our successful treatment of luminal surface hypercoagulability associated with certain endovascular procedures prompted the use of an anticoagulation protocol prospectively to improve graft patency and limb salvage for patients receiving femoral-infrapopliteal cryopreserved saphenous vein allografts. Methods: Between September 1995 and October 1999, 24 patients (15 men and nine women) were enrolled in a prospective clinical trial for salvage of 26 severely ischemic lower limbs with femoral-infrapopliteal cryopreserved saphenous vein allograft bypass grafts. All patients were treated with a protocol (aspirin, low-dose heparin, low molecular weight dextran 40, dipyridamole, and warfarin), and no immunosuppressive agents were used. The cryopreserved saphenous vein allografts were matched to patients by ABO and Rh compatibility. Indications for revascularization were ischemic rest pain (n = 8), nonhealing ulcer (n = 13), or focal gangrene (n = 5), and no usable autogenous vein was available. Follow-up ranged from 2 to 35 months (mean, 19 months). We studied the location and type of outflow anastomosis, specific outflow vessel, morbidity, death, secondary procedures (digital/transmetatarsal amputation), and complications related to the treatment protocol. Life table analyses of primary graft patency and limb salvage were compared with other current reported data. Results: Primary graft patency with Kaplan-Meier life table analysis was 96% at 6 months, 87% at 12 months, and 82% at 18 and 24 months. There were no reoperations for acute graft occlusion. One graft underwent late segmental aneurysmal degeneration and rupture. There were no procedure-related deaths or bleeding complications. During late follow-up, anticoagulation was discontinued in three patients (12%) because of gastrointestinal bleeding. Limb salvage was 88% at 6 months and 80% at 12, 18, and 24 months. Patients returned to ambulatory status that was limited only by their other comorbidities. Conclusion: Femoral-infrapopliteal bypass graft for limb salvage with a cryopreserved saphenous vein allograft can be an acceptable alternative when autogenous vein is not available. Our treatment protocol substantially improved allograft patency and limb salvage when compared with current published data. (J Vasc Surg 2000;32:731-8.)
Rate of stimulus repetition changes evoked potential amplitude: dental and auditory modalities compared.

Vertex evoked potentials (40-500 ms) elicited by painful dental stimulation were compared with those elicited by innocuous auditory stimuli across three rates of stimulus repetition: one second, four seconds, and eight seconds. In both modalities peak amplitude of the major waveform components increased linearly over log rate as stimulus repetition was slowed, and latency of the latest positive component was increased. No changes in subjective stimulus intensity across rate of repetition were reported. These observations demonstrate that the normally close relationship between subjective pain report and EP amplitude is not invariant, and they suggest that the development of EP methodology in human pain research should proceed conservatively.
A framework for assessing and predicting network loads and performance for network-centric operations and warfare

Being able to accurately analyze and predict performance of networks in Network-Centric Operations and Warfare is critical towards realistic utility of resources. In this paper, we introduce a theoretical framework to address such issues. The framework is decomposable and component-based with plug-and-play functionality. One focal point for the framework is the assessment and prediction of the effectiveness of networks, as well as, network performance and network loads in NCO/NCW. Also, the framework allows for varying levels of specificity in order to provide important analyses including pinpointing bottlenecks, and providing potential corrections. Furthermore, the framework will allow modeling at different and multiple scales, and allow for decoupling of networks and sub-networks in order to understand and predict performance issues and propagation effects of sub-networks within the NCO/NCW environment. This leads to a much better understanding of and capability to determine and restructure NCO/NCW infrastructures for overall performance, efficiency and efficacy.
A turbidimetric method for determining hyaluronidase in semen and tissue extracts.

RECENT EVIDENCE (McClean and Rowlands, 1942; Fekete and Duran-Reynals, 1943; Rowlands, 1944; Joel and Eichenberger, 1945; Werthessen et al., 1945; Leonard and Kurzrok, 1945) of the possible importance of hyaluronidase in the process of fertilization made it desirable that a simple, rapid method adaptable to routine determination of the enzyme be available. A quantitative biological test was recently proposed by Leonard and Kurzrok (1946). This was not found satisfactory when large numbers of assays were required to be made in one day. To date the available non-biological techniques for hyaluronidase determination consist of (1) measurement of the reducing substances formed by the hydrolysis of the glucosidic linkages of hyaluronic acid (Meyer, 1946), (2) the measurement of the decrease in viscosity due to enzymatic action on a given hyaluronic acid solution (Madinaveitia and Quibell, 1940), or (3) the measurement of the turbidity produced by the interaction of acidified blood serum with the hyaluronic aci...
Electrical resistivity structure beneath the North-west Atlantic Ocean

Summary Geomagnetic variations recorded on the deep sea floor of the North-west Atlantic basin have been combined with simultaneous data recorded at nearby land stations to deduce the electrical resistivity structure to depths of several hundred kilometres. Over a period interval between about 30 min and one day, vertical gradients of the geomagnetic field variations are simply interpreted as induction from a plane two-layer structure with resistivity of about 7–20 Ω m in the upper 100 km, increasing to > 20 Ω m below. The lack of suitable high-frequency data precluded resolution of structures within the upper 30–50 km. The resistivity value implied for depths below 100 km is comparable to that deduced from similar studies in the Pacific Ocean basin.
Use of light addressable potentiometric sensor (LAPS) to detect magnetically captured Escherichia coli O157:H7 in ground beef

An improved process using magnetic capture of antibody-conjugated bacteria for light addressable potentiometric sensor detection by the Threshold instrument was developed. Cells of Escherichia coli 0157:H7 were captured by the biotinylated anti-E. coli 0157 antibodies conjugated to streptavidin coated magnetic beads. Magnetically concentrated bacteria were further labeled with by fluorescein-conjugated anti-E. coli 0157 antibodies that were bound to urease-conjugated anti-fluorescein antibody. The whole bacteria-containing complex was then immobilized on 0.45 μ biotinylated nitro-cellulose membranes via streptavidin-biotin interactions. The rates of pH change associated with the production of NH 3 by conjugated urease were measured by a LAPS technique incorporated in the Threshold instrument. This approach allowed us to detect -10 4 CFU of cultured E. coli 0157:H7 in tris-buffered saline (TBS). The same approach was applied to detect the E. coli in beef hamburger spiked with the bacteria. After a 5 to 6-hour enrichment, as low as 1 CFU/g of E. coli 0157:H7 in the hamburger could be detected. In addition, the immobilized bacterial complexes on the nitro-cellulose membranes exhibited a stability longer than 48 h at 4 and 22 °C in TBS allowing the possibility of conveniently shipping collected samples rather than raw beef to testing laboratories.
Dealer behavior in the specials market for US Treasury securities

Abstract We assess dealer behavior in the specials market for US Treasury securities by comparing dealer participation in the Federal Reserve's securities loan auctions with prices in the private market. Dealer behavior is generally consistent with the law of one price and apparent violations can largely be explained by institutional differences between the private market and the Fed's program. However, for auctions that are effectively noncompetitive, dealers regularly pass up true arbitrage opportunities and frequently overpay to borrow securities. Dealers apparently do not realize that certain auctions are noncompetitive, even though the information needed to discern this fact is publicly available in advance.
Women's preferences for contraceptive counseling and decision making.

Abstract Background Little is known about what women value in their interactions with family planning providers and in decision making about contraception. Study Design We conducted semistructured interviews with 42 black, white and Latina patients. Transcripts were coded using modified grounded theory. Results While women wanted control over the ultimate selection of a method, most also wanted their provider to participate in the decision-making process in a way that emphasized the women's values and preferences. Women desired an intimate, friend-like relationship with their providers and also wanted to receive comprehensive information about options, particularly about side effects. More black and Spanish-speaking Latinas, as compared to whites and English-speaking Latinas, felt that providers should only share their opinion if it is elicited by a patient or if they make their rationale clear to the patient. Conclusion While, in the absence of medical contraindications, decision making about contraception has often been conceptualized as a woman's autonomous decision, our data indicate that providers of contraceptive counseling can participate in the decision-making process within limits. Differences in preferences seen by race/ethnicity illustrate one example of the importance of individualizing counseling to match women's preferences.
Is the recent decline in coronary heart disease mortality in the United States attributable to lower rates of influenza and pneumonia

A downturn in coronary heart disease (CHD) mortality in the United States has been observed since 1968, and an acceleration in the long-term decline in stroke deaths began in the early 1970s. In considering the causes of this secular trend, attention has been drawn to the parallel downturn in deaths from influenza and pneumonia. The slope of the downward trend for the cardiovascular causes in the summer equals that of the winter, when the potential impact of a decrease in respiratory infection would be greatest. In addition, trends in the death rate from influenza and pneumonia tended to lag behind that of CHD and stroke, in relation to each of the four sex-race groups, the magnitude of the slope of the mortality curve, and the month-by-month variation. Although cause and effect relationships cannot be defined from vital statistics alone, it would appear that the decline in cardiovascular diseases has been the primary phenomenon, reducing the number of persons in the population susceptible to respiratory infection.
Preaxial polydactyly of the foot associated with early amnion rupture: Evidence for mechanical teratogenesis?

THE SPECTRUM of resultant defects for early amnion rupture has been expanded to include defects other than those caused by amniotic band disruption per se. These include craniofacial defects, limb reduction defects, cutaneous syndactyly, body wall deficiency, a short umbilical cord, scoliosis, and growth deficiency. 1-~ The nature of these additional defects is thought to relate to early intrauterine compression of the embryo resulting from at least a temporary loss of amniotic fluid. Support for this hypothesis derives from experimental studies in rats, in which the same duster of anomalies is induced by early amnion puncture at a time equivalent to four to six weeks in the human. 6 The purpose of this communication is to report yet another potential consequence of early amnion rupture, namely, a rare form of preaxial polydactyly of the foot, observed in two unrelated patients who had evidence of early amnion rupture.
Thirty-nine cases of appendicitis in a single family pedigree

Abstract A review of the literature shows that a number of diverse hereditary constitutions are probably conducive to appendicitis. We present a pedigree containing thirty-nine individuals who have suffered from appendicitis. The tendency to appendicitis is hereditary in this pedigree, and seems to involve the transmission of several different types of predisposition.
Activation of Albumin and Other Liver-Specific Gene Expression in Fibroblast-Pancreatic Cell Hybrids: Different Roles of Transcription Factors

HNF1 and C/EBP-related proteins are transcription factors important for the activation of albumin gene expression. Fusion of mouse fibroblast (L) cells with rat pancreatic cells (AR42J) unexpectedly activated mouse albumin gene expression in the hybrid cells. In addition, several liver-specific genes such as tyrosine amino-transferase (TAT) and phosphoenolpyruvate carboxy-kinase (PEPCK) were also activated in the fibroblast-pancreatic hybrids. RNase protection assays using rat HNF1 riboprobes showed that AR42J cells and fibroblast-pancreatic hybrids expressed rat HNF1 transcripts. However, mouse or rat C/EBP alpha transcripts were not expressed in the fibroblast-pancreatic hybrids by RNase protection assays. Transfection of HNF1 expression vector alone was able to activate an albumin promoter (-1 kb, 5' flanking) promoted GPT construct in L cells, but not in HeLa cells, suggesting that different factors in L cells might interact with HNF1 to mediate activation. These results showed the global activation of liver-specific genes (including albumin, TAT, and PEPCK) in somatic cell hybrids. The presence of HNF1 in the hybrids may play a causal role. The absence of C/EBP alpha in the hybrids suggested its non-essential role in the activation of liver-specific gene expression. The other mechanisms responsible for the activation were also discussed.
FAST observations of electron distributions within AKR source regions

Observations of high-time resolution 3-D electron distributions within the source regions of Auroral Kilometric Radiation (AKR) are reported. In general, the electron data display a broad plateau over a wide range of pitch angles indicating that these distributions have been rapidly stabilized by AKR wave growth. The source of the electron instability appears to come from several features in the distribution, including an isotropic beam feature and its mirroring components, occasional electrons in the “trapped” region, as well as steep gradients present in the atmospheric loss cone. Taken together these features may provide a nearly continuous region of ∂f/∂v⟂ which could contribute to the relativistic cyclotron maser instability. Computer simulations of the evolution of the electron distribution which assume plasma conditions similar to the parameters measured by FAST show similar results to the observed electron distributions. The FAST observations also show that relativistic corrections to the AKR dispersion relation may enable a small k|| mode with a resonance condition that is able to take maximum advantage of the initial instability in the mono-energetic electron distributions within the auroral acceleration regions.
Stereoisomers of Cyclic Urea HIV-1 Protease Inhibitors: Synthesis and Binding Affinities

We have synthesized stereoisomers of cyclic urea HIV-1 protease inhibitors to study the effect of varying configurations on binding affinities. Four different synthetic approaches were used to prepare the desired cyclic urea stereoisomers. The original cyclic urea synthesis using amino acid starting materials was used to prepare three isomers. Three additional isomers were prepared by synthetic routes utilizing L-tartaric acid and D-sorbitol as chiral starting materials. A stereoselective hydroxyl inversion of the cyclic urea trans-diol was used to prepare three additional isomers. In all 9 of the 10 possible cyclic urea stereoisomers were prepared, and their binding affinities are described.
Decarboxylation of p-tyrosine: a potential source of p-tyramine in mammalian tissues

The question of the existence of a p-tyrosine decarboxylase pathway for the formation of p-tyramine in mammalian tissues remains unresolved. Development of a sensitive and specific assay for p-tyrosine decarboxylase has permitted demonstration of this activity in rat tissues and human kidney. Tyrosine decarboxylase was purified to electrophoretic homogeneity by pH 5.0 precipitation, ammonium sulfate precipitation, gel filtration, phenyl-Sepharose chromatography, DEAE-Sephacel chromatography, and preparative isoelectric focusing. A specific rabbit antiserum to tyrosine decarboxylase was also obtained. Purified tyrosine decarboxylase possessed a narrow pH dependency with an optimum at 8.0. Benzene and certain other organic solvents dramatically stimulated tyrosine decarboxylase activity of purified enzyme. Purified tyrosine decarboxylase activity also decarboxylated L-DOPA, 5-hydroxytryptophan, 3,4-dihydroxyphenylserine, o-tyrosine, m-tyrosine, phenylalanine, histidine, and tryptophan, which suggested that the purified enzyme was aromatic L-amino acid decarboxylase. This conclusion was supported by a constant ratio of 5-hydroxytryptophan decarboxylase to tyrosine decarboxylase throughout the purification scheme and by parallel immunoprecipitation of decarboxylase activities by the specific antityrosine decarboxylase antisera. Thus, we report that p-tyrosine is decarboxylated by aromatic L-amino acid decarboxylase and that this metabolic transformation may be an important source of p-tyramine in mammalian tissues. In conclusion, neuronal tissues that synthesize catecholamines or serotonin should now be considered capable of synthesizing p-tyramine and other biogenic amines.
A multi-period network design problem for cellular telecommunication systems

Abstract Mathematical Programming models for multi-period network design problems, which arise in cellular telecommunication systems are presented. The underlying network topologies range from a simple star to complex multi-layer Steiner-like networks. Linear programming, Lagrangian relaxation, and branch-and-cut heuristics are proposed and a polynomial-bounded heuristic based on an interior point linear programming implementation is described. Extensive computational results are presented on a number of randomly generated problem sets and the performance of the heuristic(s) are compared with an optimal branch-and-bound algorithm.
Dynamic and reversible self-assembly of photoelectrochemical complexes based on lipid bilayer disks, photosynthetic reaction centers, and single-walled carbon nanotubes.

An aqueous solution containing photosynthetic reaction centers (RCs), membrane scaffold proteins (MSPs), phospholipids, and single-walled carbon nanotubes (SWCNTs) solubilized with the surfactant sodium cholate (SC) reversibly self-assembles into a highly ordered structure upon dialysis of the latter. The resulting structure is photoelectrochemically active and consists of 4-nm-thick lipid bilayer disks (nanodisks, NDs) arranged parallel to the surface of the SWCNT with the RC housed within the bilayer such that its hole injecting site faces the nanotube surface. The structure can be assembled and disassembled autonomously with the addition or removal of surfactant. We model the kinetic and thermodynamic forces that drive the dynamics of this reversible self-assembly process. The assembly is monitored using spectrofluorimetry during dialysis and subsequent surfactant addition and used to fit a kinetic model to determine the forward and reverse rate constants of ND and ND-SWCNT formation. The calculated ND...
Tautomeric energetics of xanthine oxidase substrates: xanthine, 2-oxo-6-methylpurine, and lumazine

Abstract The stability of the tautomers of each of the three important substrates of xanthine oxidase, xanthine, 2-oxo-6-methylpurine, and lumazine, was examined by quantum mechanical calculations. The geometries of these tautomers were optimized at the AM1, Hartree–Fock (HF/6-31G), and hybrid Hartree–Fock/density functional theory (B3LYP/6-31G(d)) levels of theory. The single point energies of some of the more stable tautomers for each of the substrates were calculated at the B3LYP/6-311+G(2d,p) level of theory. The Conductor Polarized Continuum Model (CPCM) was used to evaluate the solvent effects on the relative stabilities of these tautomers. The calculations clearly identify the lowest energy tautomeric form for xanthine and lumazine. On the other hand, there appear to be three tautomers for 2-oxo-6-methylpurine, with only minor energetic differences in vacuo. In water, however, only one of them predominates. The lowest energy tautomers presumably represent the predominant tautomeric forms at the molybdenum center of xanthine oxidase during catalysis. Implications of these computational results are discussed in the context of enzyme catalysis.
Assessing Noise Exposures in Farm Youths

Abstract Objective: This exploratory study evaluated the feasibility of field exposureassessment methods to characterize the noise sources and levels that farm youthsexperience during a typical workday. Methods: Detailed exposure assessments were performed with a sample of 10 farm youths working on Vermont dairy farms to characterize potential noise hazards typical in the farm setting. Personal and area noise measurements were taken using noise dosimeters. Information concerning work- and non-work-related noise exposure histories was collected via questionnaire. Results: The average age was 15.5 years (SD 2.5, range 10-18). Youths started working at an average age of 8.4 years (SD 2.3, range 6-12) and during the summer months worked an average of 41.3 hours per week (SD 32.3, range 2-68). Two youths exceeded the OSHA action level, having eight-hour time-weighted averages of 95 dBA and 92 dBA, or alternatively, doses of 206% and 127%. (The OSHA action level for the hearing conservation amendment is an eigh...
Interphase Spectral FISH: Tailoring a diagnostic and minimal residual disease (MRD) assay for oncology

Spectral FISH is a powerful multiplex fluorescence in situ hybridization (FISH) technique requiring only a single hybridization to target disease-specific multiple chromosomal aberrations in interphase nuclei, using combinatorial fluorescence and digital imaging microscopy developed for the ASI™ Spectral Karyotyping System. In oncology, it becomes a particularly useful tool to diagnosis and monitor clonal aberrations not readily amenable to PCR technology, including aneuploidy or recurrent deletions of variable chromosomal regions, such as del(5q), del(6q), or del(7q). Multiple aneuploidies are common in both hematologic malignancies and solid tumors, with particularly frequent involvement of chromosomes 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 18, 21, X, and Y. To assess ploidy status in low or non-mitotic cells from various neoplastic disorders, including breast cancer, lymphoma. acute rymphoblastic leukemia (ALL), acute myeloid leukemia, and cells recovered from bladder washings suspicious for recurrence of bladder cancer, we developed an initial Spectral FISH oncology panel of six oentromeric probes for chromosomes 7, 8, 9, 10, X, and Y, using unique two-dye combinations of four fluorophores: Cy5.5, Spectrum Green, Spectrum Orange, and Spectrum Red. Spectral FISH readily identified clonal aberrations in all recurrent bladder cancer cases tested and identified MRD in hyperdiploid ALL, providing proof of concept. Validations of the Spectral FISH assay were performed by classic cylogenetics, when mitotic cells were available, or by standard FISH analyses. Advantages of Spectral FISH include increased sensitivity by surveying multiple genetic targets in specimens with limited cell numbers for analysis, identifying aberrations in poor growth/no growth specimens, and Die ability to detect specific genetic aberrations at the single cell level to assess MRD or early stages of recurrent disease. To obviate the limitations of low cell numbers, spectral FISH requires only a single hybridization, while allowing simultaneous detection of multiple numerical changes, with the ability to select combinations of informative probes highly associated with, or characteristic for a specific malignancy. Disadvantages include labor intensive screening, and interpretative challenges associated wilh signal overlap in highly polyploid samples, and focal plane distortions resulting in false positives or negatives. Spectral FISH, as a sensitive MRD assay, has significant potential clinical application, allowing early detection of new or re-emerging clones, and earlier therapeutic intervention.
Reconstruction of pristine and hydrolyzed quartz surfaces.

Reconstruction of the most common pristine and hydrolyzed surfaces of quartz was investigated with periodic density functional theory calculations. Surface energies of reconstructed pristine faces, pertinent to quartz growth morphologies in melts, are found to range from 0.071 eV/A2 for the (101) surface to 0.139 eV/A2 for the (001) surface, and they increase as (101) < (102) < (112) < [(100), (111)] < (110) < (001). Four types of reconstruction reactions are observed: (1) formation of two-membered rings from vicinal silyl and siloxy sites, (2) formation of a pair of tricoordinated/unicoordinated oxygen atoms, (3) formation of three-membered rings, and (4) transformation of silanone sites into siloxane sites. The main features of reconstructed pristine quartz surfaces are two-membered rings formed from bridged siloxy and silyl sites on all investigated surfaces, a stable site complex with geminal positively charged tricoordinated and negatively charged unicoordinated oxygen atoms revealed on the (112) su...