cssi/SciSciGPT-SciSciNet huggingface dataset:
Validation of FAPi PET biodistribution by immunohistochemistry in patients with solid cancers: a prospective exploratory imaging study

1000 Introduction: Fibroblast activation protein (FAP)-expressing cancer associated fibroblasts (CAFs), a major component of tumor stroma, confer treatment resistance, promote local progression, metastasis and immunosuppression. Because FAP is selectively expressed in the tumor stroma of many cancers, radiolabeled small molecule ligands targeting FAP are being explored for their use as pan-cancer theranostic agents. The objective was to define the incidence and degree of FAP expression by immunohistochemistry (IHC) across various cancers using Tissue Microarrays (TMAs) and to explore whether gallium-68 FAPi-46 PET image biodistribution faithfully reflects tumor FAP expression from resected tumor and non-tumor specimens. Methods: This study was a prospective, exploratory, open-label, single-center imaging trial in cancer patients conducted in 2020. Referred volunteer patients scheduled to undergo surgical resection of the primary tumor and/or metastases were eligible. Patients underwent one whole body 68Ga-FAPI-46 PET/CT scan. Subsequently, patients underwent surgical resection of the primary tumor and/or metastasis. The Outcome Measure was the Correlation of 68Ga-FAPI-46 PET maximum standardized uptake value (SUVmax) with FAP IHC score in cancer and non-cancer tissue. Trial Registration: ClinicalTrials.gov Identifier: NCT04147494. Results: The incidence of FAP expression in TMAs from 14 cancers ranged from 25 to 100% (mean 76.6± 25.3). 15 patients with the following cancer types were included: colorectal (n=4), head and neck (n=3), pancreas (n=2), breast (n=2), stomach (n=1), esophagus (n=2) and uterus (n=1). All 15 patients subsequently underwent surgery after the scan with a mean time interval of16.1 ± 14.4 days (range 1 - 50 days). Tumor resection was not attempted in 2 patients because unresectable. FAPI SUVmax and IHC score were higher in cancer tissue than in normal tissue: mean FAPI SUVmax 7.4±4.6 (range 1.5-15.9) vs 1.6±1.2 (range 0.4-5.1), (p<0.001) and mean FAP IHC score 2.38±0.65 vs 0.54±0.66 (p<0.001), respectively. The FAP IHC score was positively correlated with FAPI SUVmax (pairwise p=0.001, repeated measures correlations r=0.85 (95% CI 0.53-0.95), p<0.001). Conclusions: The 68Ga-FAPi-46 PET biodistribution across multiple cancers reflects FAP expression as determined by IHC. This translational validation paves the way for large scale prospective trials on the use of 68Ga-FAPi-46 PET/CT as a biomarker and stratification tool for FAP-targeted therapies.
Suppressing the Spread of Email Malcode using Short-term Message Recall

Outbreaks of computer viruses and worms have established a pressing need for developing proactive antivirus solutions. A proactive antivirus solution is one that reliably and accurately detects novel malicious mobile code and one that either prevents damage or recovers systems from the damage that such code inflicts. Research has indicated that behavioral analysis, though provably imprecise, can feasibly predict whether novel behavior poses a threat. Nevertheless, even the most reliable detection methods can conceivably misclassify malicious code or deem it harmful only after substantial damage has taken place. The study of damage control and recovery mechanisms is, therefore, clearly essential to the development of better proactive systems. Earlier work has demonstrated that undoing the damage of malicious code is possible with an appropriate behavior monitoring and recording mechanism. However, it remains that even if a system is recovered, the virulent code may have already propagated to other systems, some of which may not be well-equipped in terms of proactive defenses. Curbing the propagation of undesired code once it has left the boundaries of a system is a hard problem and one that has not received much attention. This work focuses on a specific instance of this difficult problem: viruses and worms that spread by email. In this paper, we explore how advantageous it would be to have a short-term email undo mechanism whose purpose is to recall infected messages. Simulation results demonstrate that such ability can substantially curb the damage of email viruses on a global scale. The results are encouraging because they only assume technology that is either readily available or that is otherwise clearly practical today
Self-Adjusting Weighted Averages in Standard Scoring

Like many of their counterparts in university teaching, law professors routinely rely on all-or-nothing final examinations. But all-or-nothing final exams put enormous pressure on students, who often labor for months with no meaningful feedback on their mastery of the material.One alternative to the all-or-nothing final exam consists of administering some sort of initial graded assignment. Assigning a relatively modest weight to the initial assignment maintains the primacy of the comprehensive final exam. To further minimize the pressure that accompanies the initial assignment, I propose an algorithm for adjusting the weight of the grade on the initial assignment so that students who boost their performance by the time of the final exam will benefit from their improvement. By the same token, students who do well on the initial assignment may wish to “lock in” some of the benefit of that performance as a hedge against declining performance on the final exam.The method for self-adjusting weighted averages described in this paper achieves both of those objectives. It does so in strictly parametric terms, thereby removing guesswork and potential capriciousness in grading decisions. By using the standard logistic function to adjust the relative weight of z-scores, the method prescribed in this paper preserves the symmetry inherent in the presumptively elliptical distribution of grades.
Concast: design and implementation of a new network service

This paper introduces concast, a new network service. Concast is the inverse of multicast: multiple sources send messages toward the same destination, which results in a single message being delivered to the destination. The received message appears to come from the concast group rather than any particular receiver. Different forms of concast service can be defined by varying the mapping from the set of sent messages to the received message. The service is useful for preventing implosion and reducing bandwidth consumption in cases where many senders transmit to the same receiver-for example in aggregating (or suppressing) positive (or negative) acknowledgements. We define the semantics of a simple concast service that is the inverse of multicast, as well as a more general custom concast, which allows users to define certain aspects of the service's semantics. We describe how to implement the service so that it scales approximately as well as IP multicast. We also present results from a simulation study showing that concast provides significant benefits in a layered-video application.
Evaluation of Turbocharger Power Assist System Using Optimal Control Techniques

In the paper we employ numerical optimal control techniques to define the best transient operating strategy for a turbocharger power assist system (TPAS). A TPAS is any device capable of bi-directional energy transfer to the turbocharger shaft and energy storage. When applied to turbocharged diesel engines, the TPAS results in significant reduction of the turbo-lag. The optimum transient strategy is capable of improving the vehicle acceleration performance with no deterioration in smoke emissions. These benefits can be attained even if the net energy contribution by the TPAS during the acceleration interval is zero, i.e., all energy is re-generated and returned back to the energy storage by the end of the acceleration interval. At the same time the total fuel consumption during the acceleration interval may be reduced. These results are compared to the "conventional" vehicle (without TPAS) and to the case when the supplemental energy is applied directly to or taken directly from the crankshaft as in a parallel hybrid vehicle configuration. Comparison with the conventional vehicle and with the parallel hybrid vehicle reveals the mechanism by which TPAS can reduce pumping losses at the initial phase of acceleration thereby improving fuel economy.
Actinides: Organometallic Chemistry

An actinide organometallic complex is one containing an actinide-carbon σ-bond, an actinide-carbon π-bond, or a combination of both. Actinide organometallic complexes are known for the actinide (An) elements from thorium through californium; the vast majority of the reports on organoactinide compounds, however, deal with thorium and uranium. The latter elements have isotopes, for example, thorium-232 (t 1/2 = 1.41 × 1010 years) and uranium-238 (t 1/2 = 4.468 × 109 years), with extremely long half-lives. Modern organoactinide chemistry is characterized by the existence not only of actinide analogs to many classes of d-transition metal complexes but also of increasingly common reports of compounds and types of reactions unique to the actinide series. Keywords: actinide; substituted cyclopentadienyl ligands; catalysis; small molecule activation; non-Cp ligands
An overview of the global HIV/AIDS epidemic, with a focus on the United States.

The HIV/AIDS epidemic is a global human tragedy especially in sub-Saharan Africa. The pandemic affects people in the primer of their lives moving from at-risk populations to broader cross- sections of society. There have been more than 47 million adults and children infected since the beginning of the epidemic and more than 18.8 million people have died. Over 95% of the global total of all AIDS cases are in the developing world with prevalence among adults at less than 1% in India and Europe to more than 10% in several African countries. The overwhelming majority of all infections globally are acquired through unprotected sexual intercourse with at least 70% resulting from heterosexual intercourse. There have been more than 733374 AIDS cases reported to the Centers for Disease Control and Prevention in the US since the beginning of the epidemic and more than 430000 deaths. The largest number and proportion of AIDS cases reported have occurred among gay and bisexual men. This trend continues today although racial and ethnic minorities women and youth are becoming infected in increasing proportions. The South has the most people living with AIDS followed by the northeast. The global situation is improving in some areas but even if all HIV transmission could be completely stopped tomorrow the long- term health social and economic consequences will be devastating well into the 21st century. The magnitude of the epidemic and the continuing explosive risk of infection coupled with the economic and infrastructural realities of the regions of the world make prevention the only realistic approach. (authors)
Modified proximal perineal urethrostomy technique for treatment of urethral stricture in goats.

Objective To report a modified procedure for perineal urethrostomy (PU) in goats. Study Design Case series. Animals Adult castrated male pet goats (n = 11) that had recurrence of urinary tract obstruction after one or more surgical procedures for obstructive urolithiasis. Methods Medical records (May 2008–February 2011) of goats that had a modified proximal PU were reviewed for history, signalment, and intraoperative and postoperative complications. Follow up was obtained through clinical examination or by telephone interview of owners or referring veterinarians. Results Ten goats survived to discharge. Postoperative complications included hemorrhage (n = 7), misdirected urine stream (3), obstructive urolithiasis (2), and bladder atony, dysuria, dehiscence, or delayed healing (1 each). One goat died acutely 15 hours after surgery from peritonitis, pleuritis, hemorrhagic cystitis, and hepatic lipidosis, and 1 goat was euthanatized 14 months after surgery because of renal failure and persistent cystitis. Urethrostomy sites were patent and functional in 9 goats available for long-term follow-up (>12 months). Conclusions Transection of penile body attachments from the pelvis and careful mucocutaneous apposition may decrease the risk of postoperative urethral stricture formation in goats after PU. Hemorrhage is common after the procedure but does not affect clinical outcome.
Experimental Validation of Sex Differences in Spatial Behavior Patterns of Free‐Ranging Snakes: Implications for Social Interactions

Social interactions often play a significant role in determining patterns of spatial use. Although snakes are generally thought of as asocial, recent spatial dispersion studies suggest that the spatial ecology of snakes may be more strongly influenced by social interactions than previously thought. We investigated the spatial behavior patterns of a western cottonmouth (Agkistrodon piscivorus) population in east Texas by uniquely combining radio-telemetry studies on free-ranging snakes with experimental arena trials with captive individuals from the same population. Observations from the radio-telemetry study on free-ranging A. piscivorus indicated that females were more gregarious than males. In the follow-up study, spatial dispersion data from captive snakes maintained in experimental field arenas yielded similar results to spatial behavior patterns of free-ranging individuals. When compared to random experimental controls, these data suggest that observed spatial behavior patterns are related to mechanisms associated with both active avoidance among males and conspecific attraction among females. In addition to uniquely combining both free-ranging and captive observations, this is the first snake study to demonstrate sex differences with both of these divergent (attraction and avoidance) spatial patterns within a single population. Thus, similar to other vertebrate groups, a growing body of literature suggests that social interactions in snakes should be strongly considered in interpretations of spatial ecology and behavior.
Outflow tract ventricular tachycardia mapped to the coronary arteries: anatomical correlates and management strategies.

Coronary Artery Ventricular Tachycardia. Background The coronary cusps have been well described as a successful site for ablation in patients with symptomatic outflow tract ventricular tachycardia. The earliest site of activation is rarely found at the ostia or into the main coronary arteries. The exact anatomic substrate, diagnostic characteristics, and therapeutic approaches for such instances are poorly understood. Methods We retrospectively reviewed outflow tract ventricular arrhythmia (OTVA) ablations done at Mayo Clinic Rochester from 2003 to 2011 (total VT: 414; outflow tract VT: 106). Three cases were identified where the earliest site of activation was not within the cusp but rather at or within the coronary ostia (3/414 for all VT: 0.7%; 3/106 for all OTVT: 2.8%). Results In 1 patient, the left main coronary artery (LMCA) was found to have electrograms (EGMs) recorded with bipolar mapping that preceded activation in the cusps or the left ventricular outflow tract. In 2 cases, the right coronary ostium and proximal right coronary artery recorded the earliest signals. Intracardiac echocardiographic guidance was used to successfully ablate these arrhythmias targeting the aortic route (1 patient) or the right coronary cusp (2 patients), and essentially isolated the focus of origin from the ventricular outflow tracts. Detailed mapping of surrounding structures, including the atrial appendages, the contralateral outflow tract, and the coronary venous system excluded far-field mapping in the artery as a cause for early activation at the ostial location. Local EGM characteristics suggested an unusually lengthy supravalvar myocardial extension as the likely arrhythmogenic substrate. Ablation was successful without coronary arterial or valvular injury and without valvular or root stenosis. Conclusions Endocardial ablation isolating foci of origin in the vicinity of the coronary ostia is a challenging procedure but can be performed safely with appropriate visualization and is effective in the treatment of OTVA.
Development of Digital Control for Machines Designed to Evaluate/Rehabilitate Muscular Deficits

Development of digital feedback control is addressed for a series of machines, manufactured by Isotechnologies, Inc. for use by therapists in evaluating and rehabilitating musculoskeletal problems and injuries. These machines, called Isostations, allow movement in three dimensions against graded, controllable resistance generated by forcing fluid through hydraulic servo valves. Design considerations are presented, problem areas are identified, and preliminary valve control simulations are discussed.
Protein Kinase C-Regulated Aβ Production and Clearance

Alzheimer’s disease (AD) is the most common form of dementia among the elderly population. AD, which is characterized as a disease of cognitive deficits, is mainly associated with an increase of amyloid β-peptide (Aβ) in the brain. A growing body of recent studies suggests that protein kinase C (PKC) promotes the production of the secretory form of amyloid precursor protein (sAPPα) via the activation of α-secretase activity, which reduces the accumulation of pathogenic Aβ levels in the brain. Moreover, activation of PKCα and mitogen-activated protein kinase (MAPK) is known to increase sAPPα. A novel type of PKC, PKCe, activates the Aβ degrading activity of endothelin converting enzyme type 1 (ECE-1), which might be mediated via the MAPK pathway as well. Furthermore, dysregulation of PKC-MAPK signaling is known to increase Aβ levels in the brain, which results in AD phenotypes. Here, we discuss roles of PKC in Aβ production and clearance and its implication in AD.
Community trends in the use and characteristics of persons with acute myocardial infarction who are transported by emergency medical services

Abstract Objective Limited data exist on recent trends in ambulance use and factors associated with ambulance use in patients hospitalized with acute myocardial infarction (AMI), particularly from the more generalizable perspective of a community-wide investigation. This population-based prospective epidemiologic study describes the decade-long trends (1997-2007) in the use of emergency medical services (EMS) by residents of the Worcester, Massachusetts, metropolitan area who are hospitalized for AMI and the characteristics of patients with AMI who are transported to the hospital by EMS (n = 3789) compared with those transported by other means (n = 1505). Methods The study population consisted of 5294 patients hospitalized for AMI at 11 greater Worcester medical centers in 5 annual periods between 1997 and 2007. Information on the use of EMS and the factors associated with EMS use was obtained through the review of hospital medical records. Results There was a progressive increase in the proportion of greater Worcester residents with AMI who were transported to central Massachusetts hospitals by ambulance over time (66.9% transported in 1997; 74.9% transported in 2007). Patients transported by EMS were older, more likely to be women, and more likely to have a greater prevalence of previously diagnosed comorbidities. Conclusion Our findings provide encouragement for the use of EMS in residents of a large central New England community hospitalized with AMI. Despite increasing trends in ambulance use, more research is needed to explore the reasons why patients with AMI do not use EMS in the setting of an acute cardiac emergency.
Calcium‐permeable AMPA receptors are expressed in a rodent model of status epilepticus

Objective To characterize the plasticity of AMPA receptor (AMPAR)-mediated neurotransmission in the hippocampus during status epilepticus (SE).
The New Information Poor: How Limited Access to Digital Scholarly Resources Impacts Higher Education

The “new” information poor are the individuals and communities who have computer and Internet connectivity, but cannot access scholarly information due to prohibitive costs. Pratt Institute's School of Information and Library Science (SILS) represents such a community and is the subject of this case study. Three measures were analyzed: SILS' four “core” classes were surveyed to determine how many required readings were available via the library; a survey was sent to 31 SILS instructors; and we conducted in-depth interviews with two SILS instructors. While “information poor,” the data suggest our respondents are resourceful in finding ways to cope with their disadvantage.
Characterization of low-barrier hydrogen bonds 4. Basis set and correlation effects: an ab initio and DFT investigation

Abstract High-level ab initio and density functional calculations conclude that formic acid and formate anion form a very short, strong hydrogen bond in the gas phase. This system is proposed as a model for the interactions present during many enzyme-catalysed reactions. The results of an extensive basis set study suggests that 6–31+G(d,p) is an excellent and sufficient basis set for the further study of these types of system. Hartree-Fock calculations consistently underestimated the energy of interaction between a formic acid and a formate anion (22 kcal mol−1) while overestimating the potential energy barrier for transfer of a proton from formic acid to formate anion (2 kcal mol−1). Calculations at correlated levels of theory, including DFT, show a stronger energy of interaction (hydrogen bond energy) between formic acid and formate anion (27 kcal mol−1), and predict little or no barrier (0.3 kcal mol−1) for proton transfer. The density functional methods (BLYP and B3LYP) perform almost identically to other correlated ab initio methods such as MP2, MP3, and MP4.
HIF-2α downregulation in the absence of functional VHL is not sufficient for renal cell differentiation

Background Mutational inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene has been linked to hereditary as well as sporadic clear cell renal carcinomas. The product of the VHL gene, pVHL, acts to target hypoxia-inducible factor alpha (HIF-α) subunits for ubiquitination and subsequent degradation. Using an RNA interference approach to lower levels of HIF-2α in two different renal cell lines that lack functional pVHL, we have tested the contribution of HIF-2α toward cellular pVHL activities.
Talk of the town

William Whiston: Honest Newtonian. By James E. Force. Cambridge University Press: 1985. Pp.208. 25, 37.50.
Fast edge-preserving image denoising via group coordinate descent on the GPU

We present group coordinate descent algorithms for edge-preserving image denoising that are particularly well-suited to the graphics processing unit (GPU). The algorithms decouple the denoising optimization problem into a set of iterated, independent one-dimensional problems. We provide methods to handle both differentiable regularizers and the absolute value function using the majorize-minimize technique. Specifically, we use quadratic majorizers with Huber curvatures for differentiable potentials and a duality approach for the absolute value function. Preliminary experimental results indicate that the algorithms converge remarkably quickly in time.
Impact of vital signs screening & clinician prompting on alcohol and tobacco screening and intervention rates: a pre-post intervention comparison

Background Though screening and intervention for alcohol and tobacco misuse are effective, primary care screening and intervention rates remain low. Previous studies have increased intervention rates using vital signs screening for tobacco misuse and clinician prompts for screen-positive patients for both alcohol and tobacco misuse. This pilot study's aims were: (1) To determine the feasibility of combined vital signs screening for tobacco and alcohol misuse, (2) To assess the impact of vital signs screening on alcohol and tobacco screening and intervention rates, and (3) To assess the additional impact of tobacco assessment prompts on intervention rates.
Nonsense mutations in the amylomaltase gene and other loci of Streptococcus pneumoniae.

Maltose-negative mutations in the amylomaltase gene of Streptococcus pneumoniae were examined for the presence of nonsense mutations. Out of 28 single-site mutants tested, 3 were shown to be suppressible by an amber suppressor previously found by Gasc et al. (1979). In the presence of the suppressor these mutants manifested 10–30% of wild type amylomaltase activity. In addition to the amylomaltase governed by malM, and the maltosaccharide phosphorylase governed by malP (which maps to the side of malM distal to the regulatory gene, malR), a new maltose-inducible protein, governed by another gene, malX, was observed in gel electrophoretic patterns. The malX gene maps on the side of malM proximal to the malR gene. The approximate molecular weights of the amylomaltase, phosphorylase and malX polypeptides are 62,000, 87,000 and 50,000, respectively. There appear to be no polar effects of the nonsense mutations in the malM gene on synthesis of the gene products of either malP or malX. In a search for nonsense mutants at other loci, one was found in the end gene, which governs the major endonuclease, a membrane enzyme. None were detected among 5 mismatch-repair defective hex mutants analyzed.
Carbon source regulation of cephem antibiotic production by resting cells of Streptomyces clavuligerus and its reversal by protein synthesis inhibitors

Abstract The effect of utilizable carbon sources on the production of cephem antibiotics by Streptomyces clavuligerus has been studied. The pattern of utilizable carbon sources was found to be very restricted. Glycerol, maltose and starch supported the most extensive growth. Increasing the initial concentrations of carbon sources decreased both the volumetric and the specific production of cephems. A resting cell system was adopted for this study. Linear production of cephems continued for 4–7 h. The production rate of the resting cell system was higher with mycelia harvested at an early exponential stage than with those harvested at a late stage of growth. Addition of carbon source to the resting cell system decreased the production rate of cephems. This suppressive effect was prevented by the addition of chloramphenicol (or streptomycin) although uptake of carbon source was not inhibited by such a protein synthesis inhibitor.
Reduced ability of naloxone to stimulate LH and testosterone release in aging male rats; possible relation to increase in hypothalamic met5-enkephalin.

Abstract Blood luteinizing hormone (LH) and testosterone levels are lower in old than in young male rats. The specific opiate antagonist, naloxone, previously shown to increase serum LH in mature male rats, exhibited relatively little ability to raise serum LH and testosterone levels in old (18–20 mo) as compared to young (4–5 mo) male rats. The brain opiate, met5-enkephalin, which depresses LH, was found to be significantly higher in the hypothalamus of old than of young male rats. These observations suggest that hypothalamic opiates may be partially responsible for the lower serum LH and testosterone levels in old male rats, and for reduced release of these hormones in response to naloxone administration.
READING ABILITY AND PRIOR KNOWLEDGE AS PREDICTORS OF ELEVEN AND TWELVE YEAR OLDS' TEXT COMPREHENSION

The effect of prior knowledge on the comprehension of written prose paragraphs in intact, topic sentence deleted and topic and concluding sentence deleted conditions was studied. A methodology for determining prior knowledge is advanced. Subjects were average and high ability upper elementary age children. A 3 X 3 passage by treatment design was utilized. Strongest correlations were for ability and prior knowledge, and criterion measures of inferencing and summarizing. ANOVA yielded significant main effects for ability and all criterion measures except inference. Step‐wise regression analysis suggests prior knowledge as a better response predictor than ability on three of four criterion measures. The utility of an uncomplicated method for analyzing students' levels of prior knowledge valuable to researchers and classroom teachers is discussed.
Transition-metal ion impurities in KTaO 3

A systematic study of transition-metal impurity centers in pervoskites is undertaken by considering isolated ${\mathrm{Co}}^{2+},$ ${\mathrm{Fe}}^{3+},$ and ${\mathrm{Cu}}^{2+}$ point defects in ${\mathrm{KTaO}}_{3}.$ Within the generalized gradient approximation (GGA), the defect center magnetic moments agree with experiments, except for A-site ${\mathrm{Fe}}^{3+}$ complexes which exhibit $3{\ensuremath{\mu}}_{\mathrm{B}}$ and $5{\ensuremath{\mu}}_{\mathrm{B}}$ structures competitive in energies. It is argued that the anomaly is an artifact of GGA, which underestimates ${\mathrm{Fe}}^{3+}$ $3d$ electron correlations. Large $(\ensuremath{\sim}1\mathrm{\AA{}})$ off-center displacements of K-substituting impurities obtain due to metal-oxygen covalent bonding. These A-site dipoles exhibit relaxation dynamics barriers which agree well with experiments. The ${\mathrm{Fe}}^{3+}\ensuremath{-}{\mathrm{O}}_{I}{}^{2\ensuremath{-}}$ complex is considered in some detail; it exhibits Fe-O bonds considerably shorter than shell-model predictions.
Low latitude thermospheric meridional winds between 250 and 450 km altitude: AE-E satellite data

In situ measurements from the Atmosphere Explorer-E satellite are used to obtain the daily variations of the meridional wind at + or - 18 deg latitude for summer and winter between 1977 and 1979. Data are presented for altitudes around 270, 350, and 440 km. Two features showing significant seasonal variation are found: a late afternoon maximum of the poleward wind occurring in winter at 1800 LT and a nighttime maximum in the equatorward wind with the summer equatorward wind abating earlier and more rapidly than the winter wind. The characteristics of these seasonal variations are discussed in detail.
A process for creating multimetric indices for large-scale aquatic surveys

Differences in sampling and laboratory protocols, differences in techniques used to evaluate metrics, and differing scales of calibration and application prohibit the use of many existing multimetric indices (MMIs) in large-scale bioassessments. We describe an approach to developing MMIs of ecological condition that is applicable to a variety of biological assemblage types and to spatially extensive (regional, national) aquatic resource surveys. The process involves testing the performance characteristics of candidate metrics in several categories that correspond to key dimensions of biotic condition. The performance characteristics include: information content (range), reproducibility, calibration for natural gradients, responsiveness to stressor gradients, and independence from other metrics. The best-performing metric from each category is included in the final MMI. The consistency of the process enables development of separate MMIs in different regions that can be combined in a national assessment and that are more comparable across regions and taxonomic groups than a set of independently developed MMIs would be. We provide an example of the process applied to macroinvertebrate data from the US Environmental Protection Agency's Wadeable Streams Assessment (WSA) from 3045 sites (of which 1390 were WSA probability sites). The MMIs developed for the WSA demonstrate the feasibility of conducting bioassessments at continental scales and provide a basis for interpreting existing MMIs from regional- and national-level perspectives.
Bronchial Stenting Through a ProSeal Laryngeal Mask Airway

o C RACHEOBRONCHIAL STENTING is used to treat benign and malignant stenotic lesions of the central airways.1 n adults, expandable metal stents are usually placed with the id of a fiberoptic bronchoscope (FOB) through a size 8.0-mm D or larger endotracheal tube (ETT) to minimize resistance to irflow during bronchoscopy.2 A novel way of securing the irway in a patient whose trachea could only accommodate a .0-mm internal diameter (ID) ETT is described.
Electron Tunneling at the Semiconductor−Insulator−Electrolyte Interface. Photocurrent Studies of the n-InP−Alkanethiol−Ferrocyanide System

The nature of electron tunneling through self-assembled monolayer films on n-InP semiconductor electrodes is explored. The photocurrent of a semiconductor cell is measured as a function of the thickness of an alkanethiol overlayer film. This work reports a detailed investigation into the photocurrent and its dependence on control parameters of the photoelectrochemical cell. This study demonstrates that the study of the photocurrent versus chain length of the alkanethiol can be used to examine how the electron-transfer rate constant depends on the thickness of the insulating layerof particular interest is the ability to probe the distance dependence of the electronic coupling.
Effects of clodronate and alendronate on osteoclast and osteoblast co-cultures on silk–hydroxyapatite films

The goal of this study was to explore the effects of osteoporosis-related therapeutics on bone remodeling in vitro. A previously established bone-tissue mimetic system consisting of silk protein biomaterials in combination with hydroxyapatite and human cells was used for the study. Silk-hydroxyapatite films were pre-complexed with the non-nitrogenous bisphosphonate clodronate or the nitrogenous bisphosphonate alendronate and cultured with THP-1 human acute monocytic leukemia cell line-derived osteoclasts, human mesenchymal stem cell derived osteoblasts or a direct co-culture of the two cell types. Metabolic activity, calcium deposition and alkaline phosphatase activity were assessed over 12 weeks, and reconstructed remodeled biomaterial surfaces were also evaluated for quantitative morphological changes. Increased metabolic activity and increased roughness were found on the clodronate-complexed biomaterial substrates remodeled by osteoblasts and co-cultures of osteoblasts with osteoclasts, even at doses high enough to cause a 90% decrease in osteoclast metabolic activity. Films complexed with low doses of alendronate resulted in increased metabolic activity and calcium deposition by osteoblasts, while higher doses were similarly toxic among osteoclasts, osteoblasts and co-cultures. These results point to the utility of these well-defined bone-mimetic in vitro cultures as useful screens for therapeutics for bone-related diseases, particularly with the ability to conduct studies for extended duration (here for 12 weeks) and with pre-complexed drugs to mimic conditions found in vivo.
Song production in auditory mutants of Drosophila: the role of sensory feedback.

To test the role of sensory feedback in song production, we analyzed the courtship songs of Drosophila males expressing auditory mutations. We compared the courtship songs of atonal (ato), beethoven (btv) and touch-insensitive-larva-B (tilB) to wild-type songs. These mutations have in common the fact that the chordotonal organs are disrupted. Since chordotonal organs subserve both hearing (in the antenna) and proprioception (from the wing), these two potential routes for sensory feedback are defective in the mutant flies. We measured six song characters: pulse number within a train, inter-pulse interval, pulse duration, sine burst duration, the carrier frequency of the sine song and the relative amplitude of the sine song. Using multivariate analysis, we found significant differences between mutant and normal songs. In addition many mutant flies exhibit an unusual wing position during singing. The results indicate that sensory feedback plays an important role in shaping the courtship song of Drosophila.
Accelerated idioventricular rhythm complicating atrioventricular junction ablation for automatic atrial tachycardia

A 13-year-old male with histologic evidence of cardiomyopathy, drug-refractory primary atrial tachycardias, and deteriorating left ventricular function underwent transcatheter His bundle ablation to control ventricular rate. Following an initial successful ablation at the level of the atrioventricular node, the patient exhibited an accelerated escape rhythm of apparent junctional origin (ventricular cycle length = 470 msec, HV = 100 msec) with complete heart block. A second ablation procedure was undertaken, following which an accelerated idioventricular rhythm (cycle length = 500 msec) became apparent and has persisted (follow-up 15 months). Thus, findings in this patient suggest that attempts to control refractory rapid ventricular responses in cardiomyopathy patients with primary atrial tachycardias may be complicated by the potential for junctional and idioventricular sites to exhibit similar abnormally accelerated subsidiary pacemaker function.
Uptake, distribution, and elimination of dietary quinoline by rainbow trout (Salmo gairdneri).

Abstract 1. Rainbow trout ( Salmo gairdneri ) readily absorbed 14 C-quinoline from pelleted food and whole-body concentrations reached apparent equilibrium after 10 days feeding. Maximum whole body concentrations of 14 C-quinoline were only 30 ηg/g of quinoline plus metabolites after 7 days depuration. 2. Initial rates of uptake and elimination varied widely among tissues. The uptake rate constants ranged from 0.0006/day for muscle to 0.1455/day for gallbladder plus bile. Mean elimination half-life for quinoline and its metabolites ranged from 0.4 days in gills to 8.7 days for muscle. 3. Depending on tissue, 58–83% of the stored radioactivity was present as metabolites. About 14% of the radioactivity in the bile was present as glucuronide conjugates. 4. Rainbow trout eliminated 66% of the ingested dose 24 hr after feeding. Biliary and fecal excretion were minor routes of elimination.
Effective medium theory of optical properties of small particle composites

Abstract A self-consistent field approach for the calculation of optical properties of a random n-component medium composed of discrete small particles is applied to an insulator-metal mixture for the case of metal formed into small spheres. The real part of the resulting conductivity exhibits broad surface plasmon absorption and a zero-frequency percolation conductivity. This result is contrasted with the Maxwell-Gamett theory for the effective composite conductivity. The effects of an insulating coat on the metal particles' response are examined and shown to produce profound effects at low frequency. Modifications introduced by a distribution of particle sizes are examined, and a completely self-consistent form of the mean field equations for an n-component system, each of whose constituents is distributed in size, is proposed.
Global AIDS: critical issues for prevention in the 1990s.

A review of the first decade of global experience with the struggle against HIV/AIDS suggests that prevention will require both full application of existing approaches and fundamental changes in concepts and values. The critical deeper issues can be grouped under three headings: behavior, societal action, and globalism. Behavior, individual and collective, will be increasingly recognized as the major challenge for public health. However, for purposes of HIV prevention (and other issues) a sufficient understanding of behavior has not yet been developed. At the societal level, the activism of community organizations has shifted the balance of initiative in public health toward the community. The long-term implications of this evolution for roles and responsibilities at the community, national, and international levels must be explored. Finally, an understanding of global solidarity, based on respect for human rights and on the objective conditions of the modern world, will be critical for the future capabil...
The electronic clipboard: A semiautomatic anesthesia record

An electronic clipboard has been designed, built, and tested, which produces an anesthesia record semi-automatically. Physiologic data are recorded up to once a minute automatically. Two keys number and time ‘drug’ and ‘event’ entries. The accurate monitoring of heart rate and blood pressure and the timing of event data are much improved over hand-written entries.
Stochastic Acceleration of Electrons by Plasma Waves. III. Waves Propagating Perpendicular to the Magnetic Field

In this paper we consider the interaction of particles with turbulent plasma waves propagating perpendicular to the ordered magnetic field. Our investigation of the dispersion relation for waves propagating at an arbitrary angle θ with respect to the magnetic field lines indicates that the qualitative behavior of the acceleration characteristics at all angles θ≠0 are similar to that of the θ=π/2 case. We use the perpendicular case as a representative example because it leads to a much simpler analysis. Therefore, the results presented here and the results of our earlier papers dealing with the θ=0 case will give a somewhat complete picture of stochastic acceleration for all waves. Unlike the θ=0 case, where only the fundamental mode of each wave contributes, for general value of θ, and in particular for the perpendicular case, many harmonics enter into the equation, making the analysis more complicated. We develop a recipe for evaluation of the contributions of all harmonics and derive an analytic expression for the asymptotic behavior at nonrelativistic energies. We use the formalism of our previous papers and find that all Fokker-Planck coefficients for the perpendicular waves are of the same order of magnitude, so the ratio of the pitch angle to momentum (or energy) diffusion rates is of order unity at all energies and pitch angles. This is unlike the parallel case, where this ratio varies from being much less than 1 at low energies to much greater than 1 at relativistic energies. As a result, the simplifications of the transport equation arising from these inequalities are no longer applicable. On the other hand, we find that when the transport equation for the θ=π/2 case is expressed in terms of diffusion in the parallel and perpendicular components of the momentum, only diffusion in the perpendicular component is present. This again yields a one-dimensional diffusion equation and implies that the parallel momentum does not change. Consequently, we expect a rapid anisotropization of the pitch angle distribution (into a pancake-like distribution) for particles accelerated by perpendicular waves. From comparison of the acceleration rate of the thermal particles with the decay rate of the waves in hot plasmas, we find that a substantial fraction of the background plasma electrons can be accelerated through this process for reasonable values of the energy density and spectrum of turbulence.
Effect of conformation on metal ion extraction by calix[4]arene dicarboxylic acids

Synthetic routes to four calix[4]arene stereoisomers with two distal methoxycarboxy groups and two distal butoxy groups are reported. Conformations of cone, partial cone (butyl up), partial cone (acid up), and 1,3-alternate were established by 1H and 13C-NMR spectroscopy. To probe the influence of ligand conformation on metal ion complexation, extractions from aqueous solutions into 1,2-dichloroethane were performed. These included competitive alkali metal cation extractions, competitive alkaline earth metal cation extractions, and single species extractions of Pb2+ and of Hg2+. Comparisons are also made with the results for a conformationally mobile analogue in which the two butoxy groups are replaced with methoxy groups.
Availability of polycyclic aromatic hydrocarbons from lampblack-impacted soils at former oil-gas plant sites in California, USA.

Lampblack-impacted soils at former oil-gas plant sites in California, USA, were characterized to assess the sorption of polycyclic aromatic hydrocarbons (PAHs) and the concentration-dependent effects of a residual oil tar phase on sorption mechanism and availability of PAHs. Nuclear magnetic resonance spectroscopy demonstrated similar aromaticity for both lampblack carbon and the oil tar phase, with pronounced resonance signals in the range of 100 to 150 ppm. Scanning-electron microscopic images revealed a physically distinct oil tar phase, especially at high concentrations in lampblack, which resulted in an organic-like film structure when lampblack particles became saturated with the oil tar. Sorption experiments were conducted on a series of laboratory-prepared lampblack samples to systematically evaluate influences of an oil tar phase on PAH sorption to lampblack. Results indicate that the sorption of PAHs to lampblack exhibits a competition among sorption phases at low oil tar contents when micro- and mesopores are accessible. When the oil tar content increases to more than 5 to 10% by weight, this tar phase fills small pores, reduces surface area, and dominates PAH sorption on lampblack surface. A new PAH partitioning model, Kd = KLB-C(1-ftar)° + ftarKtar (α = empirical exponent), incorporates these effects in which the control of PAH partitioning transits from being dominated by sorption in lampblack (KLB-C) to absorption in oil tar (Ktar), depending on the fraction of tar (ftar). This study illustrates the importance of understanding interactions among PAHs, oil tar, and lampblack for explaining the differences in availability of PAHs among site soils and, consequently, for refining site-specific risk assessment and establishing soil cleanup levels.
Investigation of Backscatter X-Ray Imaging Techniques for Uranium Dioxide Fuel Rods

Radiography by selective detection (RSD), was investigated for its ability to determine the presence and types of defects in a UO2 fuel rod surrounded by zirconium cladding. Images created using a Monte Carlo model compared favorably with actual X-ray backscatter images from mock fuel rods. A fuel rod was modeled as a rectangular parallelepiped with zirconium cladding, and pencil beam X-ray sources of 160 kVp (79 keV avg) and 480 kVp (218 keV avg) were generated using the Monte Carlo N-Particle Transport Code (MCNP) to attempt to image void and palladium (Pd) defects in the interior and on the surface of the fuel pellet. It was found that the 160 kVp spectrum was unable to detect the presence of interior defects, whereas the 480 kVp spectrum detected them with both the standard and the RSD backscatter methods, though the RSD method was very inefficient. It was also found that both energy spectra were able to detect void and Pd defects on the surface using both imaging methods. Additionally, two mock fuel ...