cssi/SciSciGPT-SciSciNet huggingface dataset:
Examining the correlations between drop size distribution parameters using data from two side-by-side 2D-video disdrometers

Abstract As part of a long-term observation campaign, over 5000 pair samples of temporally matched 1-minute averaged drop size distribution (DSD) measurements have been recorded by two side-by-side (frequently calibrated) 2D-video disdrometers. The measurement campaign was conducted in Huntsville, Alabama, over a ten-month period, and includes a variety of rain types and regimes. The datasets have been used to examine, (i) the relationship between the mass-weighted mean diameter (D m ) and the standard deviation of the mass spectrum (σ M ) without any assumption on the DSD form, and (ii) the relationship between the shape parameter (μ) and slope parameter (Λ) of the gamma form of the DSD. A number of methods were used to estimate μ and Λ, including: a normalizing procedure, the method of moments, the maximum likelihood method and the L-moment method. The physical validity of the σ M –D m relationship is examined by, (i) relating the estimated D m versus the estimated σ M from the same disdrometer datasets and, (ii) by ‘cross-relating’ D m from one disdrometer with the corresponding σ M from the second disdrometer dataset. The same procedures were repeated to examine the physical validity of the μ–Λ relation. It is shown that the transformed variable σ M ′ = σ M D m − 1.65 , which is uncorrelated with D m , has a narrow histogram and that σ M ′ ≈ constant can form a constraint which may well be applicable to other rain climatologies. For the μ–Λ relationship, the variation between μ from one unit and Λ by the second unit showed, as expected, larger scatter than using estimates from the same unit but not excessively so given that the μ estimates from the two units themselves show some instrument-to-instrument variability. While we cannot ascertain that the removal of any statistical correlations necessarily implies that the μ–Λ relation is physical, we have gone on to show that instrument limitations of accurately measuring the number concentration at the small drop end (D
A 1600-year history of the Labrador Current off Nova Scotia

A multicore from Emerald Basin, on the conti- nental margin off Nova Scotia, has a modern 14 C age at the top, and other 14 C dates indicate a linear sedimenta- tion rate of � 30 cm/ka to 1600 calendar years BP. This rate is great enough to record century-to-millennial scale changes in the surface and deep (� 250 m) waters in the basin that are influenced by the Labrador Current. We applied five proxies for seawater temperature changes to the sediments of Emerald Basin, including the percent abundance and the oxygen isotope ratio (d 18 O) of the polar planktonic foraminifer N. pachyderma (s.), the unsaturation ratio of alkenones (U k¢ 37) produced by prymnesiophyte phytoplankton, and the d 18 O and Mg/Ca of benthic foraminifera. All five proxies indicate the ocean warmed suddenly sometime in the past 150 years or so. The exact timing of this event is uncertain because 14 C dating is inaccurate in recent centuries, but this abrupt warming probably correlates with widespread evidence for warming in the Arctic in the nineteenth century. Because the Canadian Archipelago is one of the two main sources for the Labrador Current, warming and melting of ice caps in that region may have affected Labrador Current properties. Before this recent warming, sea surface temperature was continually lower by 1-2 � C, and bottom water was colder by about 6 � C in Emerald Basin. These results suggest that there was no Medieval Warm Period in the coastal waters off Nova Scotia. Because there is also no evidence of medieval warming in the Canadian archipelago, it seems likely that coastal waters from Baffin Bay to at least as far south as Nova Scotia were continually cold for � 1500 of the past 1600 years.
Three-Dimensional Residual Stress Effects on the Fatigue Crack Initiation in Rails

A rail is simulated as an elastic-plastic kinematic hardening steel having a T-shaped cross section and finite length in the rolling direction. The direct analysis method and the finite element method are combined to solve for the steady-state residual stress/strains and cyclic plastic strain amplitudes. In the present analysis, some special loading cases are investigated. Results show that tensile residual stresses occur deep in a rail head over a large area of the substrate. These phenomena, which are observed in rail steel after service, cannot be deduced from a half plane or half space analysis.
A stepwise regression method for estimating dominant electromechanical modes

Summary form only given. Prony analysis has been applied to estimate inter-area oscillation modes using phasor measurement unit (PMU) measurements. To suppress noise and signal offset effects, a high-order Prony model usually is used to over-fit the data. As such, some trivial modes are intentionally added to improve the estimation accuracy of the dominant modes. Therefore, to reduce the rate of false alarms, it is important to distinguish between the dominant modes that reflect the dynamic features of a power system and the trivial modes that are artificially introduced to improve the estimation accuracy. In this paper, a stepwise-regression method is applied to automatically identify the dominant modes from Prony analysis. A Monte-Carlo method is applied to evaluate the performance of the proposed method using data obtained from simulations. Field-measured PMU data are used to verify the applicability of the proposed method. A comparison of results obtained using the proposed approach with results from a traditional energy-sorting method shows the improved performance of the proposed method.
Effects of Differences in National Culture on Auditors' Judgments and Decisions: A Literature Review of Cross-Cultural Auditing Studies from a Judgment and Decision Making Perspective

SUMMARY: Motivated by the growing cultural diversity of new hires in audit firms, this paper reviews the literature on cross-cultural differences in auditors' judgment and decision making (JDM). The overarching aim of the review is to summarize the current state of knowledge and compare our understanding of cross-cultural auditors' JDM with the broader cross-cultural JDM research in psychology to stimulate applied research. We develop a framework that categorizes those auditor judgments and decisions most likely affected by cross-cultural differences. The categories include auditors' confidence, risk and probability judgments, risk decisions, conflict decisions, and ethical judgments. We contribute to the cross-cultural audit research in four ways. First, we provide a framework by which future research can be synthesized within auditing and compared with psychology. Second, we recommend specific research questions to respond to both the gaps in extant literature and the changing multicultural environment ...
Group B streptococcal neonatal and infant infections

Group B streptococcal neonatal sepsis is a significantly underestimated problem. Epidemiologic studies revealed an incidence of 2 per 1,000 live births and a mortality rate of 1 per 1,000 live births. Vaginal cultures for group B were positive in 4.6 per cent of women at delivery, and 1.2 per cent of their infants had positive thorat cultures. Two distinct types of sepsis were seen in 43 infected infants. One type presented within hours of birth with respiratory distress, and the second presented as meningitis in the late neonatal period. The pattern and severity of disease appeared to be related to the group B serotype isolated. Antepartum vaginal cultures and treatment of group B-positive women will prevent most of these cases of neonatal sepsis. Eradication of the organism is dependent upon evaluation of the husband, who may harbor group B in the urethra.
A unifying poset perspective on alternating sign matrices, plane partitions, Catalan objects, tournaments, and tableaux

Alternating sign matrices (ASMs) are square matrices with entries 0, 1, or -1 whose rows and columns sum to 1 and whose nonzero entries alternate in sign. We present a unifying perspective on ASMs and other combinatorial objects by studying a certain tetrahedral poset and its subposets. We prove the order ideals of these subposets are in bijection with a variety of interesting combinatorial objects, including ASMs, totally symmetric self-complementary plane partitions (TSSCPPs), staircase shaped semistandard Young tableaux, Catalan objects, tournaments, and totally symmetric plane partitions. We prove product formulas counting these order ideals and give the rank generating function of some of the corresponding lattices of order ideals. We also prove an expansion of the tournament generating function as a sum over TSSCPPs. This result is analogous to a result of Robbins and Rumsey expanding the tournament generating function as a sum over alternating sign matrices.
Ab initio study of the optical properties of Si-XII

We present a first-principles calculation of the optical excitation spectrum of Si-XII, a high-pressure, metastable phase of silicon in the R8 structure. Recent calculations of the quasiparticle spectrum have shown Si-XII to be semiconducting with a small, indirect band gap. In this paper we solve the Bethe-Salpeter equation to obtain the optical spectrum of this material. We then compare our calculated optical spectrum with experimental data for other forms of silicon commonly used in photovoltaic devices. These include cubic, polycrystalline, and amorphous forms of silicon. We find that the calculated values of the optical functions relevant to photovoltaic absorption in Si-XII show greater overlap with the incident solar spectrum than those found in these other silicon phases.
Enantioselective synthesis of nagilactone F via vinylsilane-terminated cationic cyclization

An enantioselective total synthesis of nagilactone F is described. Functionalized tricyclic intermediate 3 was prepared using a high-yielding acetal-initiated/vinylsilane-terminated polyene cyclization of 5. Intramolecular alkoxy radical-mediated remote functionalization established the D-ring of the nagilactone system.
A Weinreb nitrile oxide and nitrone for cycloaddition.

The cycloaddition of Weinreb amide functionalized nitrile oxide/nitrones with a range of dipolarophiles has been explored.
Concatenated group theoretic codes for binary asymmetric channels

A brief description of group theoretic codes is given and their suitability for binary asymmetric channels is exemplified.Previous research has shown the superiority in the information rate of the group theoretic codes over the existing codes for binary asymmetric channels and has left open the problems posed by the encoding/decoding procedures.The present paper introduces more sophisticated codes constructed from the already existing single 1-error correcting group theoretic codes.The new class of codes, which we will refer to as concatenated group theoretic codes, will have improved encoding/decoding features while maintaining a high information rate comparable with that of equivalent length group theoretic codes.As their name indicates, a code of length 2n will be obtained by concatenating two sets of group theoretic codes of length n.
The acetazolamide challenge: imaging techniques designed to evaluate cerebral blood flow reserve

Cerebral blood flow was analyzed by the stable xenon (Xe)/CT scanning technique in 29 patients with significant vascular lesions before and after administration of an acetazolamide (Diamox) vasodilatory challenge. Three response types were identified: I, normal flow before Diamox with flow augmentation after Diamox; II, low flow before Diamox with flow augmentation after Diamox; and III, low or normal flow before Diamox with no augmentation or decreased flow after Diamox. Twenty-four percent of the patients studied qualified for category III. We believe that patients in this category represent a group of individuals without blood flow reserve whose clinical management should include careful consideration of their hemodynamic status. The Xe/CT scanning technique with the addition of Diamox flow challenge is a clinically accessible and effective method for assessing cerebral blood flow and blood flow reserve.
D-branes, monopoles and Nahm equations

Abstract We study the correspondence between 11b solitonic 1-branes and monopoles in the context of the 3-brane realization of D = 4 N = 4 super Yang-Mills theory. We show that a bound state of 1-branes stretching between two separated 3-branes exhibits a family of supersymmetric ground states that can be identified with the ADHMN construction of the moduli space of SU(2) monopoles. This identification is supported by the construction of the monopole gauge field as a space-time coupling in the quantum mechanical effective action of a 1-brane used as a probe. The analysis also reveals an intriguing new aspect of the 1-brane theory: the transverse oscillations of the 1-branes in the ground states are described by non-commuting matrix valued fields which develop poles at the boundary. Finally, the construction is generalized to SU(n) monopoles with arbitrary n > 2.
Response, stability and conservation laws for the sleeping top problem☆

Abstract Application of the notion of separability and commutativity of some parameter matrices, to equations of motion of a gyroscopic system, illustrated by the “sleeping top” problem, can be reformulated in a transformed domain in which they are uncoupled. The new uncoupled equations lead to a simple formulation of the response, stability, and the establishment of a complete set of conservation laws. Their counterparts in the original physical variables are recovered by the utilization of the rotation matrix which connects the two domains.
Science, computational science, and computer science: at a crossroads

We describe computational science as an interdisciplinary approach to doing science on computers. Our purpose is to introduce computational science as a legitimate interest of computer scientists.We present a possible foundation for computational science. These foundations show that there is a need to consider computational aspects of science at the scientific level. We next present some obstacles to computer scientists' participation in computational science. We see a cultural bias in computer science that inhibits participation. Finally, we indicate areas of mutual interests between computational science and computer science.
Currency Mismatch, Openness and Exchange Rate Regime Choice

Abstract The paper analyzes the choice of an exchange rate regime for a small open economy indebted in foreign-currency, incorporating the financial accelerator. Conventional wisdom suggests that floating regimes should insulate the economy from real shocks. I show that this result depends on the degree of openness of the economy and foreign-currency indebtedness and, in fact, does not hold for relatively closed economies. The transmission mechanism relies on non-linearities in the impact of unanticipated real price changes on the external finance premium in the spirit of Fisher (1933) .
A Search for Wolf-Rayet Stars in the Small Magellanic Cloud

We report on a comprehensive search for Wolf-Rayet (W-R) stars in the SMC using interference filter imaging. Photometry of over 1.6 million stellar images on multiple, overlapping fields covering 9.6 deg2 found the previously known W-R stars at very high significance levels, two known Of-type stars, plus additional candidates, which we examined with slit spectroscopy. We discovered two new Wolf-Rayet stars, both of type "WN3 + abs," bringing the total number in the SMC to 11. We discuss their spectra, as well as reclassifying the previously known ones with our new data. Our survey also revealed four newly found Of-type stars, including one of the O5f?p type, which is one of the earliest type stars known in the SMC. Another newly identified Of star is AV 398 (O8.5 If), a star often used in extinction studies under the assumption that it is of early B type. We recover S18 (AV 154), a B[e] star whose spectrum currently lacks He II λ4686 emission but which must have had strong emission a year earlier; we compare this star to S Dor, suggesting that it is indeed a luminous blue variable. We also find a previously unknown symbiotic star whose spectrum is nearly identical to the Galactic symbiotic AG Dra. More important, perhaps, than any of these discoveries is the demonstration that there is not a significant number of W-R stars waiting to be discovered in the SMC. The number of W-R stars is a factor of 3 times lower in the SMC (per unit luminosity) than in the LMC. This strongly suggests that at the low metallicity that characterizes the SMC only the most massive stars can evolve to W-R type.
A study in resistance to institutional change: The lost game of Latin American land reform

Abstract This paper seeks an explanation of the limited success of land reforms in redistributing land in Latin America during the 1960s and 1970s, in spite of their widespread implementation. A rational choice model of farmer behavior incorporating transaction costs on labor and credit, and a game-theoretical approach between landlords and the state are used for that purpose. We show that land reform failed to be redistributive because it sought to first modernize large farms, which allowed landlords to reinforce their power over the state. This, in turn, enabled them either to obtain credible commitments of nonexpropriation if they would modernize, or to successfully use rent seeking to externalize the cost of modernization and make expropriation with compensation no longer feasible.
The free electron laser sideband instability reconsidered

Abstract The one-dimensional fast-time averaged Hamiltonian is derived in a free electron laser (FEL) for electrons passing through a constant parameter, linear wiggler and a radiation field. The exact unperturbed orbits without sidebands are obtained for all particles and arbitrary separatrix height δγ. Integration in action-angle variables of the linearized Vlasov equation with perturbing sidebands over the unperturbed orbits yields the sideband growth rate for both trapped and untrapped particles. The unperturbed distribution f 0 is in an equilibrium with the main signal field. It is found that upper and lower sidebands that are symmetric relative to the FEL frequency have opposite growth rates. There is no differentiation in the magnitude of the gain between upper and lower sidebands. The stability is determined by the sign of d f 0 d ω b , i.e., the relative population of oscillation quanta hω b , where ω b is the bounce frequency around resonance. The shear d ω b d J , where J is the action variable, is stabilizing and distributions with gradients d f 0 d J localized near the separatrix have the minimum growth rates. The structure and scaling of the unstable spectrum are different from previous results obtained for electrons localized at the bottom of the ponderomotive well.
Stresses in an Infinite Strip Containing a Semi-Infinite Crack

Stresses in infinitely long strip of finite width containing semiinfinite crack calculated for displaced clamped boundaries, using Wiener-Hopf technique
A Message from the Vice President of Publications on New Developments in Signal Processing Society Publications

Electronic publishing through IEEE Xplore offers the possibility of augmenting papers with multimedia examples - including audio, image, and video files - which provide concrete illustrations of the utility of a new algorithm. It is encouraged for all authors to take advantage of these opportunities, which are especially relevant to many problems in signal processing and can increase the impact of their work. To make the papers more easily reproducible, it is encouraged to submit code that can be accessed through IEEE Xplore with the paper. IEEE Xplore is also now augmenting the paper presentation with links to related content and citation information, and more developments are in the works to make the presentation more useful to readers.
Crater streaks in the Chryse Planitia region of Mars: Early Viking results

Abstract High-resolution images of Chryse Planitia and eastern Lunae Planum from the early revolutions of Viking Orbiter I permit detailed analyses of crater-associated streaks and interpretation of related eolian processes. A total of 614 light and dark streaks were studied and treated statistically in relation to: (1) morphology, morphometry, and orientation, (2) “parent” crater size and morphology, (3) terrain type in which they occured, (4) topographic elevation, and (5) meteorological data currently being acquired by Viking Lander I. Three factors are apparent: (1) light streaks predominate, (2) most streaks form in association with fresh bowl-shaped craters, and (3) most light streaks are of the “parallel” type, whereas dark streaks are approximately evenly divided between convergent and parallel forms; moreover, very few light or dark streaks are divergent or fan-shaped. Light streaks have an average azimuth of 218° (corresponding to winds from the northeast), which approximates the orientation of 197 ± 14° for eolian “drifts” observed by the Viking Lander imaging team (Binder et al. , 1977). This lends support to the hypothesis that light streaks are deposits of windblown sediments. Dark streaks are oriented at an azimuth of 42° (approximately opposite that of light streaks) and are nearly in line with the dominant wind direction currently recorded by the Viking meteorology instruments (Hess et al. , 1977). Although the size of the sample area is not uniform among the various terrain types, the highest frequency of streaks per unit area occurs in the knobby terrain. This is partly explained by the probable production of fine-grained material (weathered from the knobs) to form streaks and other eolian features, and the higher wind turbulence generated around the knobs. The lowest frequency of streaks occurs on the elevated plateaus. The light streaks in Chryse Planitia appear to be relatively stable and to result from deposition of windblown material during times of relatively high velocity northeasterly winds. Dark streaks are more variable and probably result from erosion by southwesterly winds. Both types will be monitored during the extended Viking mission and the results compared with lander data.
The Hale solar sector boundary

A Hale solar sector boundary is defined as the half (Northern Hemisphere or Southern Hemisphere) of a sector boundary in which the change of sector magnetic field polarity is the same as the change of polarity from a preceding spot to a following spot. Above a Hale sector boundary the green corona has maximum brightness, while above a non-Hale boundary the green corona has a minimum brightness. The Hale portion of a photospheric sector boundary tends to have maximum magnetic field strength, while the non-Hale portion has minimum field strength.
Synthesis and biological activities of aldose reductase inhibitors bearing acyl benzenesulfonamides as carboxylic acid surrogates

Abstract We have synthesized alrestatin derivatives 1–11 possessing acyl benzenesulfonamide groups as surrogates for the carboxylic acid moiety of alrestatin. Most of the compounds were inactive as aldose reductase inhibitors compared to alrestatin, however, some of them demonstrated selectivity towards inhibition of rat kidney aldehyde reductase compared to rat lens aldose reductase suggesting that structural differences may exist between the carboxylic acid binding domains of these closely related enzymes. The chemoreactive derivatives 9 and 10 suggested the presence of a nucleophile(s) at the carboxylic acid binding site on aldose reductase.
Preparation and Chemistry of Stable Azidoiodinanes: 1-Azido-3,3-bis( trifluoromethyl)-3-(1H)-1,2-benziodoxol and 1-Azido-1,2-benziodoxol-3-( 1H)-one.

Abstract Azidoiodinanes 2,4,6 can be prepared from benziodoxols 1,3 and trimethylsilyl azide in the form of stable, crystalline compounds. These compounds are potentially useful reagents for electrophilic azidonation of organic substrates. For example, reaction of azide 6 with cyclohexene affords 2-azidocyclohexanone 7 in moderate yield.
Borrowing genes from Chlamydomonas reinhardtii for free fatty acid production in engineered cyanobacteria

Photosynthetically derived fuels, such as those produced by microalgae, are touted as a future renewable energy source and a means for achieving energy independence. Realization of these claims, however, will require fuel production rates beyond the native capabilities of these microorganisms. The development of a metabolic engineering toolkit for microalgae will be key for reaching the production rates necessary for fuel production. This work advances the toolkit for cyanobacterial fuels by exploring the use of eukaryotic algal gene sources for free fatty acid biosynthesis rather than the traditional bacterial and plant sources. Many species of eukaryotic algae naturally accumulate high levels of triacylglycerol, a compound requiring three fatty acid side chains. Triacylglycerol accumulation implies that eukaryotic algae have naturally efficient enzymes for free fatty acid production, representing an unexplored resource for metabolic engineering targets. In this work, the model cyanobacterium, Synechococcus elongatus PCC7942, was engineered for free fatty acid production by targeting three main rate-limiting steps: (1) fatty acid release, catalyzed by a thioesterase, (2) fixation of carbon by ribulose-1,5-bisphosphate carboxylase/oxygenase, and (3) the first committed step in fatty acid biosynthesis, acetyl-CoA carboxylase. The recombinant acyl-ACP thioesterase and acetyl-CoA carboxylase were derived from the model green alga, Chlamydomonas reinhardtii CC-503. By targeting these proposed rate-determining steps, free fatty acid production was improved on a cell weight basis; however, the overall concentration of excreted free fatty acid did not increase. Recombinant gene expression was optimized by using native promoters, and while expression improved, the free fatty acid yield did not likewise increase. From physiological measurements, it was determined that free fatty acid production in S. elongatus PCC7942 is ultimately limited by the negative physiological effects associated with free fatty acid synthesis rather than bottlenecks within the metabolic pathway. This work demonstrates the successful expression of algal genes in a cyanobacterial host, but further improvement in free fatty acid yields will only be possible when the negative effects of free fatty acid production are mitigated.
Stock price decreases prior to executive stock option grants

Abstract This study examines abnormal stock price changes prior to executive stock option grants. Executives have the incentive and opportunity to manage the timing of their communications of inside information to the market during the period just prior to the date of their stock-option grant so as to reduce the exercise price of their options. Executives benefit from temporary stock price decreases before the grant date and by stock price increases after the grant date. Executive stock option grants create a unique opportunity for insiders to profit by manipulating the timing of information flowing to the market without engaging in insider trading. Using data on 783 stock-option grants to chief executive officers, we find a statistically significant abnormal decrease in stock prices during the 10-day period immediately preceding the grant date.
Magnetic hydrogen atmosphere models and the neutron star RX J1856.5–3754

RX J1856.5−3754 is one of the brightest nearby isolated neutron stars (INSs), and consider- able observational resources have been devoted to it. However, current models are unable to satisfactorily explain the data. We show that our latest models of a thin, magnetic, partially ionized hydrogen atmosphere on top of a condensed surface can fit the entire spectrum, from X-rays to optical, of RX J1856.5−3754, within the uncertainties. In our simplest model, the best-fitting parameters are an interstellar column density NH ≈ 1 × 10 20 cm −2 and an emitting area with R ∞ ≈ 17 km (assuming a distance to RX J1856.5−3754 of 140 pc), temperature T ∞ ≈ 4.3 × 10 5 K, gravitational redshift zg ∼ 0.22, atmospheric hydrogen column yH ≈ 1gc m −2 , and magnetic field B ≈ (3-4) × 10 12 G; the values for the temperature and magnetic field indicate an effective average over the surface. We also calculate a more realistic model, which accounts for magnetic field and temperature variations over the NS surface as well as general relativistic effects, to determine pulsations; we find that there exist viewing geometries that produce pulsations near the currently observed limits. The origin of the thin atmospheres required to fit the data is an important question, and we briefly discuss mechanisms for pro- ducing these atmospheres. Our model thus represents the most self-consistent picture to date for explaining all the observations of RX J1856.5−3754.
On fundamental groups with the quotient topology

The quasitopological fundamental group $$\pi _{1}^{qtop}(X,x_0)$$ is the fundamental group endowed with the natural quotient topology inherited from the space of based loops and is typically non-discrete when $$X$$ does not admit a traditional universal cover. This topologized fundamental group is an invariant of homotopy type which has the ability to distinguish weakly homotopy equivalent and shape equivalent spaces. In this paper, we clarify various relationships among topological properties of the group $$\pi _{1}^{qtop}(X,x_0)$$ and properties of the underlying space $$X$$ such as ‘ $$\pi _{1}$$ -shape injectivity’ and ‘homotopically path-Hausdorff.’ A space $$X$$ is $$\pi _1$$ -shape injective if the fundamental group canonically embeds in the first shape group so that the elements of $$\pi _1(X,x_0)$$ can be represented as sequences in an inverse limit. We show a locally path connected metric space $$X$$ is $$\pi _1$$ -shape injective if and only if $$\pi _{1}^{qtop}(X,x_0)$$ is invariantly separated in the sense that the intersection of all open invariant (i.e. normal) subgroups is the trivial subgroup. In the case that $$X$$ is not $$\pi _1$$ -shape injective, the homotopically path-Hausdorff property is useful for distinguishing homotopy classes of loops and guarantees the existence of certain generalized covering maps. We show that a locally path connected space $$X$$ is homotopically path-Hausdorff if and only if $$\pi _{1}^{qtop}(X,x_0)$$ satisfies the $$T_1$$ separation axiom.
Revisiting the Age of Enlightenment from a collective decision making systems perspective

The ideals of the eighteenth century's Age of Enlightenment are the foundation of modern democracies. The era was characterized by thinkers who promoted progressive social reforms that opposed the long-established aristocracies and monarchies of the time. Prominent examples of such reforms include the establishment of inalienable human rights, self-governing republics, and market capitalism. Twenty-first century democratic nations can benefit from revisiting the systems developed during the Enlightenment and reframing them within the techno-social context of the Information Age. This article explores the application of social algorithms that make use of Thomas Paine's (English: 1737-1809) representatives, Adam Smith's (Scottish: 1723-1790) self-interested actors, and Marquis de Condorcet's (French: 1743-1794) optimal decision making groups. It is posited that technology-enabled social algorithms can better realize the ideals articulated during the Enlightenment.
The life and death of URLs in five biomedical informatics journals.

Abstract Objective To determine the decay rate of Uniform Record Locators (URLs) in the reference section of biomedical informatics journals. Methods URL references were collected from printed journal articles of the first and middle issues of 1999–2004 and electronically available in-press articles in January 2005. We limited this set to five biomedical informatics journals: Artificial Intelligence in Medicine, International Journal of Medical Informatics, Journal of the American Medical Informatics Association: JAMIA, Methods of Information in Medicine, and Journal of Biomedical Informatics. During a 1-month period, URL access attempts were performed eight times a day at regular intervals. Results Of the 19,108 references extracted from 606 printed and 86 in-press articles, 1112 (5.8%) references contained a URL. Of the 1049 unique URLs, 726 (69.2%) were alive, 230 (21.9%) were dead, and 93 (8.9%) were comatose. URLs from in-press articles included 212 URLs, of which 169 (79.7%) were alive, 21 (9.9%) were dead, and 22 (10.4%) were comatose. The average annual decay, or link rot, rate was 5.4%. Conclusion The URL decay rate in biomedical informatics journals is high. A commonly accepted strategy for the permanent archival of digital information referenced in scholarly publications is urgently needed.
Hybrid protein formation of E. coli alkaline phosphatase leading to in vitro complementation.

In vitro complementation has been demonstrated for alkaline phosphatase-negative mutants of E. coli . Enzymically active alkaline phosphatase can be formed by mixing monomer subunits derived from inactive purified proteins which are antigenically related to the wild-type enzyme of E. coli . Preparations of these proteins purified from four different phosphatase-negative mutants of E. coli could be reacted in pairs to yield partially active enzyme. Experimental evidence indicates that the active protein is a hybrid molecule composed of a monomer from each of the mutant proteins used in the reaction. The monomers, which canJse prepared from the native protein by mild acid treatment or reduction with thioglycollate in urea, undergo a temperature and metal-dependent bimolecular reaction to yield a product distinct from normal enzyme but with partial enzymic activity. The normal alkaline phosphatase protein is composed of two identical subunits whose structure is determined by a single functioning genetic unit. These results thus support the theory of hybrid protein formation which has been proposed to account for intra-cistron complementation.
A slow and dark atomic beam

We demonstrate a method to produce a very slow atomic beam from a vapor cell magneto-optical trap. Atoms are extracted from the trap using the radiation pressure imbalance caused by a push beam. An additional transfer beam placed near the center of the trap transfers the atomic beam into an off-resonant state. The velocity of the atomic beam has been varied by changing the intensity of the push beam or the position of the transfer beam. The method can be used to generate a continuous, magnetically guided atomic beam in a dark state.
Tohoku earthquake: a surprise?

Abstract We consider three questions related to the 2011 Tohoku mega‐earthquake: (1) Why was the event size so grossly underestimated by Japan’s national hazard map? (2) How should we evaluate the chances of giant earthquakes in subduction zones? (3) What is the repeat time for magnitude 9 earthquakes off the Tohoku coast? The maximum earthquake size is often guessed from the available history of earthquakes, a method known for its significant downward bias. We show that historical magnitudes systematically underestimate this maximum size of future events, but the discrepancy shrinks with time. There are two quantitative methods for estimating the corner magnitude in any region: a statistical analysis of the available earthquake record and the moment conservation principle. However, for individual zones the statistical method is usually ineffective in estimating the maximum magnitude; only the lower limit can be evaluated. The moment conservation technique, which we prefer, matches the tectonic deformation rate to that predicted by earthquakes with a truncated or tapered magnitude–frequency distribution. For subduction zones, the seismic or historical record is insufficient to constrain either the maximum or corner magnitude. However, the moment conservation principle yields consistent estimates: for all the subduction zones the corner magnitude is of the order 9.0–9.7. Moreover, moment conservation indicates that variations in estimated corner magnitude among subduction zones are not statistically significant. Another moment conservation method, applied at a point on a major fault or plate boundary, also suggests that magnitude 9 events are required to explain observed displacement rates at least for the Tohoku area. The global rate of magnitude 9 earthquakes in subduction zones, predicted from statistical analysis of seismicity as well as from moment conservation, is about five per century; five actually happened.
Computation of viscous flow in curved ducts and comparison with experimental data

A three dimensional analysis for fully viscous subsonic internal flow is evaluated. The analysis, designated PEPSIG, solves an approximate form of the Navier-Stokes equations by an implicit spatial marching procedure. Results of calculations are presented for laminar flow through two different circular cross-sectioned 180 degree bends, and for laminar and turbulent flow through circular and square cross-sectioned 22.5 to 22.5 degree S-ducts. Quantitative comparisons with experimental data are shown for all cases. Special emphasis is placed on verifying the ability of the analysis to accurately predict the distorted flow fields resulting from pressure-driven secondary flows.
ANALYTICAL AND GRAPHICAL AIDS FOR THE FATIGUE DESIGN OF WELDMENTS

There are four important attributes of weldments which, together with the magnitude of the fluctuating stresses applied, determine their resistance to metallic fatigue: the ratio of the applied or self-induced axial and bending stresses; the severity of the discontinuity or notch which is an inherent property of the geometry of the joint; the notch-root residual stresses which result from fabrication and subsequent use of the weldment; and the mechanical properties of the notch-root material in which fatigue crack initiation and growth takes place. A simple version of a more elaborate analytical model of the fatigue behavior of weldments [1] is presented here which provides analytical and graphical design aids for design.
Quantification of the joint effects of mixtures of hepatotoxic agents: evaluation of a theoretical model in mice.

Abstract An approach previously developed for studying the effects of toxic mixtures on whole organism performances (i.e., growth, mortality) was evaluated to determine its applicability and limitations at the organ system level. The approach was tested by quantifying the hepatotoxic effects of carbon tetrachloride (CCl 4 ), monochlorobenzene (MCB), acetaminophen (ACET), and selected mixtures of these compounds in male albino CF-1 mice. Based upon parallel dose-response curves, concentration addition was predicted for the mixtures of both CCl 4 + MCB and CCl 4 + ACET. The actual dose-response relationship for each mixture was empirically determined and compared to the predicted curves. In the case of the CCl 4 + MCB mixture, the observed dose-response curve did not deviate from that predicted on the basis of concentration addition. However, a similar comparison for the CCl 4 + ACET mixture revealed a statistical difference between the observed and predicted curves. The joint effects for the mixture of CCl 4 + MCB is thus classified as concentration additive. The model proves to be adequate in predicting, classifying, and describing the joint effects of these hepatotoxicants.
A mercury-catalyzed transetherification cyclization leading to fused cyclic polyethers †,‡

Abstract Dihydropyran 6 serves as a key intermediate in a route to fused cyclic polyethers. The dihydropyran was first converted to 2-hydroxy-1-γ-methoxyallyltetrahydropyrans, 10 . Mercury trifluoroacetate-catalyzed transetherification cyclization generated new bicyclic dihydropyrans, 12 , ready for additional rounds of synthesis. Attempted cyclization under stoichiometric conditions resulted in isolation of α-mercurial acetal intermediates, 11 , that could also be converted to the dihydropyran by treatment with ethyl vinyl ether.
Optimal Node Visitation in Acyclic Stochastic Digraphs with Multi-threaded Traversals and Internal Visitation Requirements

The original definition of the problem of optimal node visitation (ONV) in acyclic stochastic digraphs concerns the identification of a routing policy that will enable the visitation of each leaf node a requested number of times, while minimizing the expected number of the graph traversals. The original work of Bountourelis and Reveliotis (2006) formulated this problem as a Stochastic Shortest Path (SSP) problem, and since the state space of this SSP formulation is exponentially sized with respect to the number of the target nodes, it also proposed a suboptimal policy that is computationally tractable and asymptotically optimal. This paper extends the results of Bountourelis and Reveliotis (2006) to the cases where (i) the tokens traversing the graph can "split" during certain transitions to a number of (sub-)tokens, allowing, thus, the satisfaction of many visitation requirements during a single graph traversal, and (ii) there are additional visitation requirements attached to the internal graph nodes, which, however, can be served only when the visitation requirements of their successors have been fully met. In addition, the presented set of results establishes stronger convergence properties for the proposed suboptimal policies, and it provides a formal complexity analysis of the considered ONV formulations. From a practical standpoint, the extension of the original results performed in this paper enables their effective usage in the application domains that motivated the ONV problem, in the first place.
Soviet psychology and psychophysiology

Current Soviet psychology is rooted in two disciplines: (i) Pavlovian physiology or psychophysiology, dealing with mechanisms and controls of “higher nervous activities”, and (ii) psychology proper, dealing with mechanisms and controls of mental (conscious) acts that, too, are said to be basically related to Pavlov's doctrines and methods. How successful are these two, brain and mind, disciplines in the Soviet Union? Why are there two? Are the Russians able to synthesize them? In which are they most advanced and in which lagging? And why?
All‐Nitrogen Analogue of Ozone: Li3N3 Species

A theoretical study of ozone isoelectronic Li3N3 species has been performed. Ab initio electronic structure calculations prove the viability of the ozone-like Li3N3 molecule that might become synthesized. The predicted Li3N3 species with a novel N3(3-) molecular motif possess structural and chemical bonding features similar to that of O3 molecules and can thus be considered as an "all-nitrogen ozone".
Studies on optimum-path ratios in multicriteria De Novo programming problems

Abstract This paper proposes several optimum-path ratios for enforcing different budget levels of resources so as to find alternative optimal system designs for solving multicriteria De Novo programming problems. Then, the study of optimum-path ratios is applied to solve an optimal pattern matching problem which is formulated by the De Novo programming with a given initial budget level and an optimal pattern preferred by the decision maker. An interactive algorithm is developed to continuously reshape the problem for matching the optimal pattern. A numerical example is also used to illustrate the algorithm.
Gradient NLW on curved background in 4+1 dimensions

Author(s): Geba, Dan-Andrei; Tataru, Daniel | Abstract: We obtain a sharp local well-posedness result for the Gradient Nonlinear Wave Equation on a nonsmooth curved background. In the process we introduce variable coefficient versions of Bourgain's $X^{s,b}$ spaces, and use a trilinear multiscale wave packet decomposition in order to prove a key trilinear estimate.
The worldvolume action of kink solitons in AdS spacetime

A formalism is presented for computing the higher-order corrections to the worldvolume action of co-dimension one solitons. By modifying its potential, an explicit "kink" solution of a real scalar field in AdS spacetime is found. The formalism is then applied to explicitly compute the kink worldvolume action to quadratic order in two ex- pansion parameters-associated with the hypersurface fluctuation length and the radius of AdS spacetime respectively. Two alternative methods are given for doing this. The results are expressed in terms of the trace of the extrinsic curvature and the intrinsic scalar curva- ture. In addition to conformal Galileon interactions, we find a non-Galileon term which is never sub-dominant. This method can be extended to any conformally flat bulk spacetime.
An examination of IPO secondary market returns

Abstract IPO stock prices increased approximately 2.3% on the first day of secondary market trading over the period 1993 through 2003. While these aftermarket returns are accentuated during 1999 and 2000, they persist after the bubble burst and even increase as a percentage of total underpricing. We explore several non-mutually exclusive hypotheses to explain our findings including price support, laddering, retail sentiment, and information asymmetry. Our results are most consistent with the view that higher secondary market returns accrue to IPOs with more information asymmetries possibly due to price and aggregate demand uncertainty.
Review of recent searches for rare and forbidden dilepton decays of charmed mesons

I briefly review the results of recent searches for flavor-changing neutral current and lepton-flavor and lepton-number violating decays of D+, and D0 mesons (and their antiparticles) into modes containing muons and electrons. The primary focus is the results from Fermilab charm hadroproduction experiment E791. E791 examined 24 πll and Kll decay modes of D+ and and l+l- decay modes of D0. Limits presented by E791 for 22 rare and forbidden dilepton decays of D mesons were more stringent than those obtained from previous searches,1 or else were the first reported.
Defining predictive maturity for validated numerical simulations

The increasing reliance on computer simulations in decision-making motivates the need to formulate a commonly accepted definition for ''predictive maturity.'' The concept of predictive maturity involves quantitative metrics that could prove useful while allocating resources for physical testing and code development. Such metrics should be able to track progress (or lack thereof) as additional knowledge becomes available and is integrated into the simulations for example, through the addition of new experimental datasets during model calibration, and/or through the implementation of better physics models in the codes. This publication contributes to a discussion of attributes that a metric of predictive maturity should exhibit. It is contended that the assessment of predictive maturity must go beyond the goodness-of-fit of the model to the available test data. We firmly believe that predictive maturity must also consider the ''knobs,'' or ancillary variables, used to calibrate the model and the degree to which physical experiments cover the domain of applicability. The emphasis herein is placed on translating the proposed attributes into mathematical properties, such as the degree of regularity and asymptotic limits of the maturity function. Altogether these mathematical properties define a set of constraints that the predictive maturity function must satisfy. Based on these constraints, we propose a Predictive Maturity Index (PMI). Physical datasets are used to illustrate how the PMI quantifies the maturity of the non-linear, Preston-Tonks-Wallace model of plastic deformation applied to beryllium, a light-weight, high-strength metal. The question ''does collecting additional data improve predictive power?'' is answered by computing the PMI iteratively as additional experimental datasets become available. The results obtained reflect that coverage of the validation domain is as important to predictive maturity as goodness-of-fit. The example treated also indicates that the stabilization of predictive maturity can be observed, provided that enough physical experiments are available.