cssi/SciSciGPT-SciSciNet huggingface dataset:
Combustion-derived ultrafine particles transport organic toxicants to target respiratory cells.

Epidemiologic evidence supports associations between inhalation of fine and ultrafine ambient particulate matter [aerodynamic diameter 90%) PAH-rich, metals-poor (nickel, chromium, and vanadium concentrations all < 1 ppm) PM2.5, composed of uniformly sized, solid spheres (30-50 nm) in aggregated form. Cells of a human bronchial epithelial cell line (BEAS-2B) exhibit sequential fluorescent responses--a relatively rapid (approximately 30 min), bright but diffuse fluorescence followed by the slower (2-4 hr) appearance of punctate cytoplasmic fluorescence--after BDS is added to medium overlying the cells. The fluorescence is associated with PAH localization in the cells. The ultrafine BDS particles move down through the medium to the cell membrane. Fluorescent PAHs are transferred from the particle surface to the cell membrane, cross the membrane into the cytosol, and appear to accumulate in lipid vesicles. There is no evidence that BDS particles pass into the cells. The results demonstrate that uptake of airborne ultrafine particles by target cells is not necessary for transfer of toxicants from the particles to the cells.
Anatomic considerations for posterior iliac crest bone procurement.

Purpose The aim of this study was to identify the relative anatomic locations of relevant vital structures at risk for injury during posterior iliac crest bone graft procurement. Materials and Methods Twenty-one cadavers yielded 39 intact posterior ilia for dissection. The posterior superior iliac spine (PSIS) was used as the primary reference landmark. Measurements were made to the medial branch of the superior cluneal nerves, the superior branch of the middle cluneal nerves, the sciatic notch, and the superior gluteal vessels. Distances from the spinal midline to the superior cluneal nerves were recorded. Results The average distances from the PSIS to the superior and middle cluneal nerves, greater sciatic notch, and superior gluteal vessels were 5.7 cm (standard deviation, 1.22 cm), 6.55 cm (standard deviation, 1.53 cm), 5.3 cm (standard deviation, 0.71 cm), and 5.4 cm (standard deviation, 0.95 cm), respectively. The most medial superior cluneal nerve was identified at 3.0 to 4.9 cm from the PSIS in 23% of cases, at 5.0 to 6.9 cm from the PSIS in 61.5% of cases, and farther than 7.0 cm from the PSIS in 15.4% of cases. Conclusions This study illustrates that the most medial superior cluneal nerve is often closer to the PSIS than previously described and the same holds true for the greater sciatic notch and superior gluteal vessels. Knowledge of the anatomic locations of these important structures should allow the surgeon to avoid or decrease the complication rate of bone procurement from the posterior ilium.
When novel sentences spoken or heard for the first time in the history of the universe are not enough: toward a dual-process model of language.

Although interest in the language sciences was previously focused on newly created sentences, more recently much attention has turned to the importance of formulaic expressions in normal and disordered communication. Also referred to as formulaic expressions and made up of speech formulas, idioms, expletives, serial and memorized speech, slang, sayings, cliches, and conventional expressions, non-propositional language forms a large proportion of every speaker's competence, and may be differentially disturbed in neurological disorders. This review aims to examine non-propositional speech with respect to linguistic descriptions, psycholinguistic experiments, sociolinguistic studies, child language development, clinical language disorders, and neurological studies. Evidence from numerous sources reveals differentiated and specialized roles for novel and formulaic verbal functions, and suggests that generation of novel sentences and management of prefabricated expressions represent two legitimate and separable processes in language behaviour. A preliminary model of language behaviour that encompasses unitary and compositional properties and their integration in everyday language use is proposed. Integration and synchronizing of two disparate processes in language behaviour, formulaic and novel, characterizes normal communicative function and contributes to creativity in language. This dichotomy is supported by studies arising from other disciplines in neurology and psychology. Further studies are necessary to determine in what ways the various categories of formulaic expressions are related, and how these categories are processed by the brain. Better understanding of how non-propositional categories of speech are stored and processed in the brain can lead to better informed treatment strategies in language disorders.
Subtype-selective allosteric modulators of muscarinic receptors for the treatment of CNS disorders

Muscarinic acetylcholine receptors (mAChRs) have long been viewed as viable targets for novel therapeutic agents for the treatment of Alzheimer's disease (AD) and other disorders involving impaired cognitive function. More recent evidence indicates that mAChR activators might also have utility in treating psychosis and other symptoms associated with schizophrenia and other central nervous system (CNS) disorders. Efforts to develop mAChR subtype-selective agonists have been hampered by difficulty in achieving high selectivity for individual mAChR subtypes important for CNS function (M 1 and M 4 ) and adverse effects due to activation of peripheral mAChRs (especially M 2 and M 3 ). Major advances have now been achieved in the discovery of allosteric agonists and positive allosteric modulators of M 1 and M 4 that show greater selectivity for individual mAChR subtypes than do previous mAChR agonists. Early studies indicate that these allosteric mAChR activators have properties needed for optimization as potential clinical candidates and have robust effects in animal models that predict efficacy in the treatment of AD, schizophrenia and related disorders.
Open fiber control: a laser safety interlock technique

Laser safety has become an important issue in the design of optical data links for computers because semiconductor laser diodes, rather than LEDs, are increasingly being selected as the light source. It is very important that optical data links in the computer environment meet the requirements of a Class 1 laser product (Class 1 is the safest, least restrictive laser safety category) due to the potential for user exposure to laser radiation. This paper presents an overview of an open fiber link detection and laser control system for point-to-point data links referred to as the open fiber control (OFC) system. The system functions by detecting whenever the optical link between two transceiver ports is opened (i.e., an open connector or cut fiber) and forcing the transmitters into a low duty cycle mode of operation that maintains a Class 1 output level from the open link.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Manduca receives 2004 Excellence in Geophysical Education Award

Cathryn A. Manduca received the Excellence in Geophysical Education Award at the AGU Joint Assembly Honors Ceremony, which was held on 19 May 2004 in Montreal, Canada. The award honors “a sustained commitment to excellence in geophysical education by a team, individual, or group”
Self-assembled ring-in-ring complexes from metal–ligand coordination macrocycles and β-cyclodextrin

Abstract Ring-in-ring nanostructures can be assembled from readily available starting materials, including dipyridyl ligands, (en)Pd(NO 3 ) 2 , and β-cyclodextrin (β-CD). When a series of dipyridyl ligands are mixed with β-CD and Pd(II) in aqueous solution, various self-assembled geometries can be obtained as a result of a combination of hydrobic interactions and metal–ligand coordinations. In the cases of dipyridyl ligands with flexible linker, dinuclear coordination macrocycles M 2 L 2 are formed and included in the cavity of β-CD to form ring-in-ring complexes. When more rigid dipyridyl ligands are used, a tetranuclear coordination macrocycle M 4 L 4 prevails and shows no interaction with β-CD, as apposed to the flexible ones.
Design and development of a measurement and control system for measuring SEM magnification calibration samples

The National Institute of Standards and Technology (NIST) has provided industry with a scanning electron microscope (SEM) magnification calibration sample Reference Material (RM) 8090. The certified, Standard Reference Material (SRM) version, SRM 2090 is currently being prepared for issuance. This paper describes the design and development of a new, PC-based measurement and control system developed to facilitate the certification of the SRM 2090 artifact samples in a specialized metrology microscope. SRM 2090 is certified by moving the sample under a finely focused stationary electron beam in the metrology electron microscope. Using a laser interferometer with displacement measurements traceable to basic wavelength standards, the motion is measured while recording the secondary or backscattered electron output signal. A computer controls the motion, records the signal and interferometer value, then calculates the accurate spacing of the features, completes the statistical work and generates the NIST certificate. The original measurement system design was developed in the early 1990s. This paper outlines the effort to upgrade the system, including the replacement of the outdated measurement and control system with a new, LabVIEW based measurement and control system. The details of the new measurement and control system will be discussed and results will be presented.
The thermoelastic effect in rigor muscle of the frog

Small length changes were imposed on pairs of sartorius muscles fromRana temporaria andRana pipiens in rigor and the mechanical and thermal responses studied. Rigor was induced by soaking the muscles overnight at 0° C in a physiological salt solution containing 1.5m sodium azide and 0.4m sodium iodoacetate. Tension was measured at both the tibial and the pelvic ends of the preparation. Muscles were held at a steady tension of 20 to 76 kN m−2 and stretches or releases of 0.02 to 0.6 mm applied in pairs, with the initial change reversed several hundred milliseconds later.
Prediction of Quasi-Periodic Oscillations in Radiation Fogs. Part I: Comparison of Simple Similarity Approaches

Abstract There is considerable controversy in the literature concerning fog formation. One set of observations suggests that fog forms during a lull in turbulence, white another set of observations suggests that increased turbulence leads to fog formation. A number of first-order closure techniques are applied to numerical simulations. The results show that fog formation and development is directly correlated with the magnitude of the eddy mixing coefficients. Larger turbulence generation leads to more rapid fog development and to larger liquid water contents. The rate at which the fog top grows is directly related to the rate at which turbulence lifts the inversion. During the mature fog stage, a series of fog dissipation and redevelopment episodes occur. Liquid water develops in the upper regions of the fog during the turbulently quiet periods. Subsequent destabilization of the atmosphere increases turbulence generation and mixes the upper-level liquid water to the surface, creating surface fog intensif...
The Memory-History-Popular Culture Nexus: Pearl Harbor as a Case Study in Consumer-Driven Collective Memory:

In this paper I examine the fusing of collective memory, history and popular culture by analyzing current trends in American-made commercial films with historical events as subject matter that have also been distributed to a global audience. Pearl Harbor is the primary case study. Analysis shows that dominant historical narratives are reified by the use of what I term an 'anticipatory-driven' film experience where audience members engage in an interaction with pre-existing mainstream collective memory while their anticipation for impending climactic trauma is systematically heightened. Comparisons are made to other widely released US films about national and international events and 'non-events.' Questions are also raised about the increasing global importance of the memory-history-popular culture nexus post 9-11, and, how US produced films about 9-11 may or may not engage in the practices detailed in this analysis. In this vein the paper concludes with a discussion of how Pearl Harbor was marketed, edited and received in Japan, the second largest audience for Hollywood films and what this implies about social memory construction in a global commercial context.
A moderate glycemic meal before endurance exercise can enhance performance

The purpose of this study was to determine whether presweetened breakfast cereals with various fiber contents and a moderate glycemic index optimize glucose availability and improve endurance exercise performance. Six recreationally active women ate 75 g of available carbohydrate in the form of breakfast cereals: sweetened whole-grain rolled oats (SRO, 7 g of dietary fiber) or sweetened whole-oat flour (SOF, 3 g of dietary fiber) and 300 ml of water or water alone (Con). The meals were provided 45 min before semirecumbent cycle ergometer exercise to exhaustion at 60% of peak O2 consumption (VO2peak). Diet and physical activity were controlled by having the subjects reside in the General Clinical Research Center for 2 days before each trial. Blood samples were drawn from an antecubital vein for glucose, free fatty acid (FFA), glycerol, insulin, epinephrine, and norepinephrine determination. Breath samples were obtained at 15-min intervals after meal ingestion and at 30-min intervals during exercise. Muscle glycogen concentration was determined from biopsies taken from the vastus lateralis muscle before the meal and immediately after exercise. Plasma FFA concentrations were lower (P < 0.05) during the SRO and SOF trials for the first 60 and 90 min of exercise, respectively, than during the Con trial. Respiratory exchange ratios were higher (P < 0.05) at 90 and 120 min of exercise for the SRO and SOF trials, respectively, than for the Con trial. At exhaustion, glucose, insulin, FFA, glycerol, epinephrine, and norepinephrine concentrations, respiratory exchange ratio, and muscle glycogen use in the vastus lateralis muscle were similar for all trials. Exercise time to exhaustion was 16% longer (P < 0.05) during the SRO than during the Con trial: 266.5 +/- 13 and 225.1 +/- 8 min, respectively. There was no difference in exercise time for the SOF (250.8 +/- 12) and Con trials. We conclude that eating a meal with a high dietary fiber content and moderate glycemic index 45 min before prolonged moderately intense exercise significantly enhances exercise capacity.
Mechanical Failure Characteristics of Ceramic Multilayer Capacitors

The results of both uniaxial and biaxial flexure as well as toughness testing on actual commercial ceramic capacitor samples are reported. Necessary procedural adjustments are outlined for miniaturizing the applied-moment double-cantilever-beam test to accommodate these small samples. Strength and toughness testing showed that the metal electrodes lowered the fracture toughness and that the metal-ceramic interface was a preferred fracture path for crack propagation parallel to the electrodes. However, toughness did not clearly depend on crack propagation parallel or perpendicular to the electrodes, nor with flexural strengths. Flexural strengths were 0 to 40% lower, with the electrodes perpendicular to the tensile surface vs. parallel to the tensile surface. Fractures initiated from machining (or impact) flaws, or voids of various sizes, shapes, and locations, thus explaining the poor correlation between strength and toughness. Biaxial flexure tests of dielectric specimens of various sizes indicate that such a test could be scaled down and “calibrated” for actual testing of capacitors; e.g., a decrease in strength with increasing specimen thickness to support diameter ratio is indicated.
Analyzing Participation Frameworks in Kindergarten Writing Activity The Role of Overhearer in Learning to Write

This article focuses on the role of overhearer participation in learning to write. Using Goffman's notion of the participation framework as a linguistic structure that organizes and is organized by...
Surgical learning curve in performing palatoplasty: A retrospective study in 200 patients

Abstract Objectives The aim of the study was to assess the influence of the experience of the surgeon on the occurrence of fistulas following palatoplasty. Materials and methods A retrospective review was performed of consecutive children treated between 2006 and 2013 for cleft palate by a single surgeon. Cleft palate repair was performed using the von Langenbeck technique, Furlow palatoplasty, buccal flap or Vomer flap. Data was collected for age, sex, date of birth, syndrome, adoption, cleft palate type, type of repair, cleft width, fistula occurrence and location of fistula. Results A total of 276 operations were performed in 200 children (Veau I, II, III, IV). Mean age at surgery was 21.9 months (range: 6.2 months to 26 years 8.3 months). Postoperatively, palatal fistulas occurred in eight patients (4.0%), however, the incidence was 3.0% in the non-adoption group and 9.7% in the adoption population. In this study there was no statistically significant evidence of a surgical learning curve, and no significant associations between fistula rate and sex, adoption, syndrome, cleft type, cleft width, or type of repair. Conclusion and clinical relevance This study demonstrates a fistula formation rate of 3.0% for the non-adoption population and 9.7% for the adoption population. There was no statistically significant evidence of a learning curve during the first few years of performing cleft palate repair. No other independent risk factors for postoperative fistula formation were identified; however, the benefit of a vomer flap and subsequent reduction in fistula incidence was demonstrated.
Diagnostic thoracoscopic lung biopsy: an outpatient experience.

Abstract Background Tissue diagnosis of either interstitial lung disease or indeterminate pulmonary nodules can be obtained by either limited thoracotomy or thoracoscopic lung biopsy. Both procedures traditionally have required hospital admission. We report a series of patients undergoing outpatient thoracoscopic lung biopsy to demonstrate the safety and efficacy of this practice. Methods Sixty-two ambulatory patients with a clinical diagnosis of either interstitial lung disease or indeterminate pulmonary nodule(s) underwent thoracoscopic lung biopsy between June 2000 and June 2001. All procedures were performed with double-lumen endotracheal anesthesia and stapled wedge resection. Chest tubes were removed if no air leak was present and if chest radiograph demonstrated no residual pneumothorax. Results Of 62 patients undergoing thoracoscopic lung biopsy, 45 (72.5%) were discharged home within 8 hours of observation on the day of operation. Fourteen (22.5%) were discharged within 23 hours of their operation. Reasons for 23-hour observation included significant comorbidity (8), pain management (4), postoperative air leak (1), and conversion to muscle-sparing thoracotomy (1). Three (5%) required admission for prolonged air leak (2) or conversion to muscle-sparing thoracotomy (1). Diagnoses were obtained in 61 patients, including neoplasm (25), interstitial lung disease (18), granulomatous disease (7), and other (11). One patient was readmitted for pneumothorax. Patients diagnosed with nonbronchogenic pulmonary metastases were more likely to be discharged on the day of operation. No differences in age, smoking status, or preoperative pulmonary function testing were observed between patients requiring short-stay observation and those discharged immediately after operation. Conclusions Outpatient thoracoscopic lung biopsy is safe and effective, and has become our procedure of choice for diagnosis of either interstitial or focal lung disease.
Comparison of balance assessment modalities in emergency department elders: a pilot cross-sectional observational study

More than one-third of US adults 65 and over fall every year. These falls may cause serious injury including substantial long-term morbidity (due declines in activities of daily living) and death. The emergency department (ED) visit represents an opportunity for identifying high risk elders and potentially instituting falls-related interventions. The unique characteristic of the ED environment and patient population necessitate that risk-assessment modalities be validated in this specific setting. In order to better identify elders at risk of falls, we examined the relationship between patient-provided history of falling and two testing modalities (a balance plate system and the timed up-and-go [TUG] test) in elder emergency department (ED) patients. We conducted a cross-sectional observational study of patients ≥ 60 years old being discharged from the ED. Patient history of falls in the past week, month, 6 months, and year was obtained. Balance plate center of pressure excursion (COP) measurements and TUG testing times were recorded. COP was recorded under four conditions: normal stability eyes open (NSEO) and closed (NSEC), and perturbed stability eyes open and closed. Correlation between TUG and COP scores was measured. Univariate logistic regression was used to identify the relationship between patient-provided falls history and the two testing modalities. Proportions, likelihood ratios, and receiver-operating-characteristic (ROC) curves for prediction of previous falls were reported. Fifty-three subjects were enrolled, 11% had fallen in the previous week and 42% in the previous year. There was no correlation between TUG and any balance plate measurements. In logistic regression, neither testing modality was associated with prior history of falls (p > 0.05 for all time periods). Balance plate NSEO and NSEC testing cutoffs could be identified which were 83% sensitive and had a negative likelihood ratio (LR-) of 0.3 for falls in the past week. TUG testing was not useful for falls in the past week, but performed best for more distant falls in the past month, 6 months, or year. TUG cutoffs with sensitivity over 80% and LR(-) of 0.17-0.32 could be identified for these time periods. Over 40% of community-dwelling elder ED patients report a fall within the past year. Balance plate and TUG testing were feasibly conducted in an ED setting. There is no relationship between scores on balance plate and TUG testing in these patients. In regression analysis, neither modality was significantly associated with patient provided history of falls. These modalities should not be adopted for screening purposes in elders in the ED setting without validation in future studies or as part of multi-factorial risk assessment.
Analysis of the Sensitivity of Decision Analysis Results to Errors and Simplifications in Problem Structure: Application to Lake Erie Ecosystem Management

In practical decision analyses, the ldquocurse of dimensionalityrdquo compels one to make simplifying assumptions that can introduce errors into estimates of various indexes that interest decision-makers. These indexes include the expected performance of optimal and suboptimal strategies, the benefit of explicitly considering uncertainty, and the benefit of additional information. This paper quantifies the effects on these indexes of simplifying assumptions, including discretization of the decision space, omission of some decision variables and uncertainties from the decision tree, and disregarding of risk aversion. To reduce errors arising from discretization of the decision space, we use a multidimensional cubic spline to interpolate the performance of alternatives between a few simulated points. A case study analyzes decisions concerning phosphorus loading, fisheries management, and lower trophic research projects in Lake Erie under multiple criteria and ecological uncertainties. Results show that spline-based solutions often yield potentially superior decisions from those based on discretized decision spaces, but that omitting important uncertainties makes more of a difference in this case study's decisions and indexes than simplifying the decision space. On the other hand, incorrect multicriteria weights affect the case study's outcomes more than incorrect probabilities.
A novel technique to improve noise immunity of CMOS dynamic logic circuits

Dynamic CMOS logic circuits are widely employed in high performance VLSI chips in pursuing very high system performance. However, dynamic circuits are inherently less resistant to noises than static CMOS gates. With the increasing stringent noise requirement due to aggressive technology scaling, the noise tolerance of dynamic circuits has to be first improved for the overall reliable operation of VLSI systems. In this paper, we present a novel noise-tolerant design technique using circuitry exhibiting a negative differential resistance effect. We have demonstrated that using the proposed method the noise tolerance of dynamic logic gates can be improved beyond the level of static CMOS logic gates while the performance advantage of dynamic circuits is still retained.
Measurement of the shortening of cardiac fibers in man.

Abstract A newly devised instrument is described which permits measurement of shortening of the fibers through the internal surface of individual cardiac chambers throughout the cardiac cycle in intact, unanesthetized man. It consists of a strain gauge assembly that is an intracardiac catheter through which a flexible stylet is inserted with two extendable prongs to each of which a strain gauge is attached. The two prongs are inserted through the endocardium into the myocardium. The strain gauge assembly is connected to a full-bridged circuit, and the strain in the gauges is optically recorded. It is demonstrated that the strain in the gauges is lineally related to the spacing of the prongs. Thus, the recording represents the changes in distances between fixed points on the internal surface of the ventricles. The instrument has been found to be safe and has been employed in 12 patients without complications. Changes in the shortening of cardiac fibers and cardiac dimensions after administration of nitroglycerin and propranolol are briefly discussed.
Block arithmetic coding for source compression

We introduce "Block Arithmetic Coding" (BAC), a technique for entropy coding that combines many of the advantages of ordinary stream arithmetic coding with the simplicity of block codes. The code is variable length in to fixed out (V to F), unlike Huffman coding which is fixed in to variable out (F to V). We develop two versions of the coder: 1) an optimal encoder based on dynamic programming arguments, and 2) a suboptimal heuristic based on arithmetic coding. The optimal coder is optimal over all V to F complete and proper block codes. We show that the suboptimal coder achieves compression that is within a constant of a perfect entropy coder for independent and identically distributed inputs. BAC is easily implemented, even with large codebooks, because the algorithms for coding and decoding are regular. For instance, codebooks with 2/sup 32/ entries are feasible. BAC also does not suffer catastrophic failure in the presence of channel errors. Decoding errors are confined to the block in question. The encoding is in practice reasonably efficient. With i.i.d. binary inputs with P(1)=0.95 and 16 bit codes, entropy arguments indicate at most 55.8 bits can be encoded; the BAC heuristic achieves 53.0 and the optimal BAC achieves 53.5. Finally, BAC appears to be much faster than ordinary arithmetic coding. >
The clinical and financial burden of pre-emptive management of cytomegalovirus disease after allogeneic stem cell transplantation-implications for preventative treatment approaches.

Abstract Background aims Although cytomegalovirus (CMV) infection after allogeneic stem cell transplantation (SCT) is rarely fatal, the management of CMV by pre-emptive medication for viral reactivation has toxicity and carries a financial burden. New strategies to prevent CMV reactivation with vaccines and antiviral T cells may represent an advance over pre-emptive strategies but have yet to be justified in terms of transplantation outcome and cost. Methods We compared outcomes and post-transplantation treatment cost in 44 patients who never required pre-emptive CMV treatment with 90 treated patients undergoing SCT at our institute between 2006 and 2012. Eighty-one subjects received CD34+ selected myeloablative SCT, 12 umbilical cord blood transplants, and 41 T-replete non-myeloablative SCT. One hundred nineteen patients (89%) were at risk for CMV because either the donor or recipient was seropositive. Of these, 90 patients (75.6%) reactivated CMV at a median of 30 (range 8–105) days after transplantation and received antivirals. Results There was no difference in standard transplantation risk factors between the two groups. In multivariate modeling, CMV reactivation >250 copies/mL (odds ratio = 3, P P P Conclusions Our findings suggest that to prevent CMV reactivation, treatment should be given within 1 week of SCT. Preventative treatment may improve outcome and have significant cost savings.
Debris from space

The Quest for Comets: An Explosive Trail of Beauty and Danger. by David H. Levy. Plenum: 1994. Pp. 280. $23.95.
Newborn screening and genetic testing.

New screening techniques and diagnostic tests for genetic diseases available for newborn screening can provide information about many diseases long before they are clinically detected. However, this information creates complex questions and ethical dilemmas regarding which newborns should be tested, when testing should occur, availability and costs of tests, and how families should be counseled. There is no national policy regarding newborn screening, which leads to great variation among states’ newborn screening programs. This article reviews newborn genetic testing and provides a blueprint for clinicians to improve practice by incorporating into their care knowledge of new developments in newborn testing and screening.
Lentil Water Use and Fallow Water Loss in a Semiarid Climate

With renewed interest in legumes for green manures or as partial summer fallow replacement crops, it is important to know water requirements of these crops in semiarid agriculture. Our objective was to evaluate seasonal water use by black lentil (Lens culinaris Medikus cv. Indianhead), a potential fallow replacement crop, and to relate water use to parameters useful as soil water management tools. We measured evapotranspiration (ET) from two precision weighing lysimeters located on a Williams loam (fine-loamy, mixed Typic Argiboroll) near Sidney, MT. The lysimeters were in adjacent 180- by 180-m fields in a typical strip-crop environment of the semiarid northern Great Plains. Bowen ratio estimates of ET were also obtained. Lentil was seeded no-till into wheat (Tritium aestivum L.) stubble on one lysimeter field in 1993, and the other was left in chemical fallow. Seeded and fallow fields were rotated in 1994. Water loss by ET from lentil and fallow lysimeters was the same (25 mm) for 3 wk following seeding. Plant height was related to growing degree days (GDD) in both years. Cumulative ET was related to GDD for both years until about 800 GDD, corresponding to nearly 300 mm ET. Deciding how much water to sacrifice (with hopes of recovery during the noncrop period) becomes a matter of judgment about probable rainfall. At full bloom (2 Mg ha -1 dry matter production), the lentil crop used about 50 to 70 mm more water than fallow. Probably no more than 50 mm of water loss above that from fallow should be sacrificed if a grain crop is to be seeded the following year. From a practical standpoint, because plant height was closely related to both GDD and cumulative ET, it is plausible that a simple measure of lentil height (about 350 mm maximum) can give sufficient accuracy for determining when lentil growth, as a partial summer fallow replacement crop in a semiarid climate, should be terminated.
F. H. Jacobi on faith, or what it takes to be an irrationalist

F. H. Jacobi (1743-1819), a key figure in the philosophical debates at the close of the eighteenth century in Germany, has long been regarded as an irrationalist for allegedly advocating a blind'leap of faith'. The central claim of this essay is that this venerable charge is misplaced. Following a reconstruction of what a charge of irrationalism might amount to, two of Jacobi's most important works, the Spinoza Letters ( 17 8 5 ) and David Hume ( 17 8 7 ), are scrutinized for traces of irrationalism. Far from being an irrationalist, Jacobi is best read as questioning the analytical-geometrical model of rationality popular among his contemporaries, and of proposing a more naturalistic theory of rationality that situates it more firmly in human psychology, the ultimate import of which lies in a reconceptualization of the relation between faith and reason.
Uncovering Hidden Mathematics of the Multiplication Table Using Spreadsheets

This paper reveals a number of learning activities emerging from a spreadsheetgenerated multiplication table. These activities are made possible by using such features of the software as conditional formatting, circular referencing, calculation through iteration, scroll bars, and graphing. The paper is a reflection on a mathematics content course designed for prospective elementary teachers using the hidden mathematics curriculum framework. It is written in support of standards for teaching and recommendations for teachers in North America.
A knowledge-based SPICE environment for improved convergence and user friendliness

An environment for SPICE called NECTAR has been developed which overcomes convergence and user-interface problems with SPICE by simulating the actions taken by an expert. NECTAR recognizes patterns which cause nonconvergence and provides ways to sidestep the problem. It identifies errors in the SPICE input file and automatically corrects them. It can be used as a circuit-design aid and improves the user interface for SPICE simulations. NECTAR derives its power from knowledge acquired from expert SPICE users and circuit designers. >
Arylsulfatases A and B in Metachromatic Leukodystrophy and Maroteaux-Lamy Syndrome: Studies with 4-Methylumbelliferyl Sulfate

Metachromatic leukodystrophy (MLD), a sphingolipidosis, and Maroteaux-Lamy syndrome (MLS), a mucopolysaccharidosis, are genetically distinct diseases which have in common a markedly impaired ability to cleave the artificial substrate p-nitrocatechol sulfate (NCS) under certain specified conditions. Numerous studies employing this substrate have demonstrated deficiency of arylsulfatase A (AS-A) in MLD (1,6,7) and of arylsulfatase B (AS-B) in MLS(3, 4, 7, 13).However, several problems exist in connection with its use.
Tomographic P-wave velocity images of the Loma Prieta Earthquake asperity

Tomographic inversion is applied to delay times from local earthquakes to image 3-D velocity variations surrounding the main rupture of the 1989 Loma Prieta earthquake. The 55{times}45 square km region is represented by blocks of 1 km per side laterally and by 8 layers of varying thickness to 18 km depth. High quality P-wave arrival times recorded on the USGS CALNET array from 549 crustal earthquakes with depths of 0 to 25 km were used as sources. Preliminary results note several velocity variations (5-12%) that correlate with specific characteristics of the 1989 rupture. These include prominent high-velocity anomalies near the mainshock hypocenter and prominent low-velocity anomalies where the dip of the San Andreas fault appears to change significantly. The termination of prominent low velocity features existing primarily in the hanging wall to depths of 7-9 km, correlates with the top of the rupture zone. High-velocity variations along the fault dominate where aftershock activity is high. The high velocity anomaly located at depth along the fault is interpreted as imaging the asperity on which the Loma Prieta earthquake occurred.
A high-efficiency multistage Doherty power amplifier for WCDMA

A comprehensive analysis of multistage Doherty amplifier, which can be used to achieve higher efficiency at great back-off compared to the classical Doherty amplifier, is presented. A novel set of design equations for a generalized N-stage Doherty amplifier is introduced. For the first time, this technique is applied to the design of a WCDMA power amplifier (PA). The designed PA meets WCDMA requirements, and exhibit a power-added efficiency (PAE) of 34.5% at 6 dB back-off and 16.9% at 12 dB back-off. These PAEs are 2 times and 4 times better, respectively, than that of a single stage linear PA at the same back-off levels. The PA is capable of delivering up to 28.6 dBm of output power, and has a maximum adjacent channel power leakage ratio of -38 dBc and -51 DBc at 5 and 10 MHz offset, respectively. To the best of the author's knowledge, these represent the best reported results of a Doherty amplifier for WCDMA application in the 1.95 GHz band, to date.
Barankin Bounds on Parameter Estimation

The Schwarz inequality is used to derive the Barankin lower bounds on the covariance matrix of unbiased estimates of a vector parameter. The bound is applied to communications and radar problems in which the unknown parameter is embedded in a signal of known form and observed in the presence of additive white Gaussian noise. Within this context it is shown that the Barankin bound reduces to the Cramer-Rao bound when the signal-to-noise ratio (SNR) is large. However, as the SNR is reduced beyond a critical value, the Barankin bound deviates radically from the Cramer-Rao bound, exhibiting the so-called threshold effect. The bounds were applied to the linear FM waveform, and within the resulting class of bounds it was possible to select one that led to a closed-form expression for the lower bound on the variance of an unbiased range estimate. This expression clearly demonstrates the threshold behavior one must expect when using a nonlinear modulation system. Tighter bounds were easily obtained, but these had to be evaluated numerically. The sidelobe structure of the linear FM compressed pulse leads to a significant increase in the variance of the estimate. For a practical linear FM pulse of 1- \mu s duration and 40-MHz bandwidth, the radar must operate at an SNR greater than 10 dB if meaningful unbiased range estimates are to be obtained.
Inhibition by Dietary Ethanol of Experimental Colonic Carcinogenesis Induced by High-Dose Azoxymethane in F344 Rats

Abstract Epidemiological studies have shown an association between consumption of alcoholic beverages and increased occurrence of large bowel carcinoma, but studies in experimental models of colonic carcinogenesis have produced conflicting results. We assessed the effects of chronic dietary ethanol consumption during the preinduction and induction phase (period of acclimatization and carcinogen administration) in a high-dose azoxymethane-treated rat model (14 mg/kg/wk for 10 wk). Ten-wk-old male Fischer 344 rats were given 33% of calories as ethanol or no ethanol (controls). Pair-feeding with Lieber-DeCarli-type liquid diets provided comparable total carbohydrates, proteins, fats, and calories. After 3 wk of dietary acclimatization, injections of azoxymethane (AOM) were given s.c. to all rats in Wk 1 to 10. At necropsy in Wk 25, dramatic suppression of gastrointestinal tumorigenesis was evident in the ethanol-fed group: the prevalence of colonic tumors was 5% as compared with 91% in controls; and the prevalence of small bowel tumors was 0% versus 74% ( P 14 C]AOM metabolism, exhaled 14 CO 2 was decreased in the ethanol-fed rats, indicating suppression of AOM metabolism. Similarly, in the ethanol-fed rats the levels of the DNA adducts O 6 -methylguanine and 7-methylguanine 24 h after AOM injection were reduced in the colonic mucosa to 14 ± 7% and 61 ± 11% of controls and in the liver to 80 ± 9% and 86 ± 6 of controls. By contrast, rats changed from the ethanol diet to no-ethanol diet for 12 h prior to the dose of [ 14 C]AOM metabolized the carcinogen at a faster rate than controls, indicating loss of suppression with cessation of ethanol intake along with induction of metabolizing enzymes; DNA adduct levels were reduced in the colonic mucosa to 90 ± 13% and 76 ± 9% of controls and in the liver to 81 ± 6% and 85 ± 3% of controls. Our findings indicate that dietary ethanol during the preinduction and induction phase of the AOM model dramatically inhibits tumorigenesis, even with high dosage of carcinogen, and suggest that: ( a ) inhibition of tumorigenesis may result from suppression of metabolic activation of AOM and the consequent reduced formation of DNA adducts during the induction (initiation) phase of the model; ( b ) these antiinitiation effects of ethanol are unrelated to the epidemiological association between consumption of alcoholic beverages and large bowel cancer; and ( c ) mechanisms of action of agents found to modulate carcinogenesis in experimental models should be determined before the results can be generalized to human beings.
Safety of proton pump inhibitors and risk of gastric cancers: review of literature and pathophysiological mechanisms.

Introduction: Despite being an overall safe drug, several long-term adverse effects are associated with proton pump inhibitors (PPIs). The link between PPI use and gastric neuroendocrine tumors (NETs), gastric adenocarcinomas and Barrett’s esophagus progression gastric cancers has been investigated due to PPI-induced hypergastrinemia.Areas covered: The pathophysiological mechanisms underlying PPI exposure and gastric NETs, gastric adenocarcinomas and Barrett’s esophagus progression are discussed. The quality of randomized control studies, cohort studies and case reports investigating the link between gastric cancers and PPIs are examined. Recommendations for clinicians are provided.Expert opinion: PPIs cause a hypergastrinemic state, increasing enterochromaffin-like cell dysplasia and risk of gastric NET development, increasing gastritis severity in the context of Helicobacter pylori infection, and progression of carcinogenesis in a certain predisposed subset of Barrett’s esophagus patients. There are cas...
Assessing probabilistic wind load effects via a multivariate extreme wind speed model: A unified framework to consider directionality and uncertainty

Abstract This study presents a new approach of estimating wind load effects (responses) for various mean recurrence intervals (MRIs) with consideration of both directionality and uncertainty of wind speed and wind load effects. The joint probability distribution model of directional extreme wind speeds is established based on extreme wind speed data using multivariate extreme value theory with Gaussian Copula. The distribution of yearly maximum wind load effect is then calculated through the exceeding probability of directional wind speeds over the corresponding levels. The uncertainty of extreme response conditional on wind speed and direction is further considered using the theorem of conditional probability. The proposed analytical framework can be considered as an analytical formulation of the existing approach based on historical directional wind speed data, but with an additional capability of accounting for the uncertainty of extreme response conditional on wind speed and direction. It can also be regarded as an extension of the existing fully probabilistic methods with an additional capability of accounting for directionality. Applications of the proposed approach are presented and the results are compared with those from the existing approach to demonstrate its accuracy. The characteristics of directionality factor for wind load effects are discussed. Finally, the influence of uncertainty of extreme response conditional on wind speed and direction is further examined.
Kinetically and Crystallographically Guided Mutations of a Benzoate CoA Ligase (BadA) Elucidate Mechanism and Expand Substrate Permissivity

A benzoate CoA ligase (BadA), isolated from the bacterium Rhodopseudomonas palustris, catalyzes the conversion of benzoate to benzoyl CoA on the catabolic pathway of aromatic carboxylic acids. Herein, apparent Michaelis constants K(app)cat and K(app)M were determined for an expanded array of 31 substrates chosen to systematically probe the active site architecture of the enzyme and provide a baseline for expansion of wild-type substrate specificity. Acyl CoA products were observed for 25 of the 31 substrates; in general, BadA converted ortho-substituted substrates better than the corresponding meta and para regioisomers, and the turnover number was more affected by steric rather than electronic effects. The kinetic data are interpreted in relation to six crystal structures of BadA in complex with several substrates and a benzoyl-AMP reaction intermediate. In contrast to other known natural substrate-bound benzoate ligase structures, all substrate-bound BadA structures adopted the thiolation conformation instead of the adenylation conformation. We also observed all the aryl carboxylates to be uniquely oriented within the active site, relative to other structures. Together, the kinetics and structural data suggested a mechanism that involves substrate binding in the thiolation conformation, followed by substrate rotation to an active orientation upon the transition to the adenylation conformation. On the basis of this hypothesis and the structural data, sterically demanding active site residues were mutated, and the substrate specificity was expanded substantially versus that of BadA. Novel activities were seen for substrates with larger substituents, including phenyl acetate. Additionally, the mutant Lys427Ala identified this nonconserved residue as essential for the thiolation step of BadA, but not adenylation. These variously acylated CoAs can serve as novel substrates of acyl CoA-dependent acyltransferases in coupled enzyme assays to produce analogues of bioactive natural products.
Mixed Metal Organometallic Clusters: Precursors for Intermetallic Powders

ntial catalytic applications [1]. Also, in non-catalytic areas, there is a move to build alloy powders from large metal clusters [2]. Therefore, we have initiated a program to develop intermetallic powders from mixedmetal organometallic precursors [3]. Here we report the synthesis and characterization of iron-cobalt intermetallic powders obtained from heteroorganometallic clusters [4]. Our objective therefore is to (1) provide a simple and effective means of synthesizing iron-cobalt intermetallics (2) vary the ratio of iron to cobalt in such intermetallics, and (3) provide a method to produce homogeneous products from iron-cobalt metalorganic precursors specifically synthesized for this purpose. The resulting intermetallics may have unique magnetic characteristics.
Cellular partitioning of nanoparticulate versus dissolved metals in marine phytoplankton.

Discharges of metal oxide nanoparticles into aquatic environments are increasing with their use in society, thereby increasing exposure risk for aquatic organisms. Separating the impacts of nanoparticle from dissolved metal pollution is critical for assessing the environmental risks of the rapidly growing nanomaterial industry, especially in terms of ecosystem effects. Metal oxides negatively affect several species of marine phytoplankton, which are responsible for most marine primary production. Whether such toxicity is generally due to nanoparticles or exposure to dissolved metals liberated from particles is uncertain. The type and severity of toxicity depends in part on whether phytoplankton cells take up and accumulate primarily nanoparticles or dissolved metal ions. We compared the responses of the marine diatom, Thalassiosira weissflogii, exposed to ZnO, AgO, and CuO nanoparticles with the responses of T. weissflogii cells exposed to the dissolved metals ZnCl2, AgNO3, and CuCl2 for 7 d. Cellular met...