Kinds Of Anomalies Research Articles

Meiotic Behavior of Carica papaya L.: Spontaneous Chromosome Instability and Elimination in Important cvs. in North Indian Conditions

Cytogenetical analysis was done in tropical species of papaya that is widely cultivated for its fruits and papain production. The proper and orderly chromosome behavior of the species is a perquisite to ensure high fertility and seed set in the crop. A study on pre-meiotic and post-meiotic stages was done on commercially important cultivars of India and few exotic cultivars. The meiosis in the flower buds was highly disturbed and many meiotic irregularities were recorded from the material fixed in summar. These ranged from chromosome stickiness (44%), chromatin bridges (21.1%), laggards (4.8), chromosome diminution/degeneration (5.2), and micronucleus (5.9%) formation, in the commercially important varieties. Pollen stickiness accounting for persistent pollen adherence in groups of 3–10 was observed in all the varieties ranging from 85.95% in cv. CO2 to 11.64% in CO5. Callose deposition on tetrads accounting for adhesion of pollen grains (permanent tetrads) was also observed. These were found to have a profound effect on the pollen fertility of the cultivars, wherein most of the commercial papaya cultivars had less than 50% of fertile pollen. Thus the role of meiotic irregularities in poor seed setting and seed production capacities under northern Indian conditions, specifically during the summer season has been established. Genetic or abiotic stress factors could be responsible for inducing such kind of anomalies, which are manifested in the form of pollen sterility and poor seed setting. Crop regulation strategies need to be evolved, so that the maximum seed set and fruit production occurs after this period to off set the restrictions imposed due to irregular meiosis.

Investors' Misreaction to Unexpected Earnings: Evidence of Simultaneous Overreaction and Underreaction

Behavioral Finance aims to explain empirical anomalies by introducing investor psychology as a determinant of asset pricing. Two kinds of anomalies, namely underreaction and overreaction, have been established by an impressive record of empirical work. While underreaction defines a slow adjustment of prices to corporate events or announcements, overreaction deals with extreme stock price reactions to previous information or past performance. Theoretical models have shown that both phenomena find potential explanations in cognitive biases, that is, investor irrationality.This study investigates current and past earnings surprises and subsequent market reaction for listed US companies over the period 1983-1999. The results suggest that investors simultaneously exhibit short-term underreaction to earnings announcements and long-term overreaction to past highly unexpected earnings. A potential explanation for the reported overreaction phenomenon is the representativeness bias. As I show, the overreaction and the later reversal is stronger for events, which exhibit a long series of similar past earnings surprises.

A study of bright Southern long period variables

In this paper we present radial velocity curves of AGB variables that exhibit various kinds of anomalies: semiregular variables (SRVs) with typical mira periods, SRVs exceeding the mira 2.5 mag amplitude limit, miras with secondary maxima in their light curves, and a SRV with a long secondary period. The stars with reliable Hipparcos parallaxes from this and from previous studies are plotted in a -diagram. Our objects nicely follow the -relations determined for the LMC. This allows the pulsation mode to be identified. While all miras fall on the fundamental mode sequence, the SRVs fall on both the first overtone and fundamental mode sequences. The SRVs on the fundamental mode sequence occur at both high and low luminosities, some of them being more luminous than larger amplitude miras. This demonstrates observationally that some parameter other than luminosity affects the stability of long period variables, probably mass. First overtone pulsators all show velocity amplitudes around 4 km s-1. For the fundamental mode pulsators, the velocity amplitude shows a correlation with light amplitude. The two miras R Cen and R Nor, known for their double-peaked light curves, have velocity curves that are quite different. The R Nor velocity curve shows no evidence of the double peaks, meaning that the true pulsation period is the time between alternate minima or maxima. There is slight evidence for a double bump in the R Cen velocity curve. It is suggested that these stars are relatively massive (3–5 ).

Pressure dependence of diffusion coefficient and orientational relaxation time for acetonitrile and methanol in water: RISM/mode-coupling study

We present results of theoretical description and numerical calculation of the dynamics of molecular liquids based on the Reference Interaction Site Model (RISM)/Mode-Coupling Theory. They include the temperature–pressure (density) dependence of the translational diffusion coefficients and orientational relaxation times for acetonitrile and methanol in water at infinite dilution. Anomalous behavior, i.e. the increase in mobility with density, is observed for the orientational relaxation time of methanol, while acetonitrile does not show any deviations from the usual. This effect is in qualitative agreement with the recent data of MD simulation and with experimental measurements, which tells us that presented theory is a good candidate to explain such kind of anomalies from the microscopical point of view and with the connection to the structure of the molecules.

Chinese Legal Reform: The Case of Foreign Investment (review)

Reviewed by: Chinese Legal Reform: The Case of Foreign Investment Pitman B. Potter (bio) Yan Wang. Chinese Legal Reform: The Case of Foreign Investment. London: Routledge, 2002. xvi, 254 pp. ISBN 0-415-24971-6. After nearly twenty-five years of China's open-door policy encouraging foreign investment and trade, the scholar's bookshelf on foreign-investment law in China has become rather crowded. China's entry to the World Trade Organization in 2001 stimulated a renewed wave of interest in the ways that China's legal system has responded to and sought to manage expanded foreign investment relations. While there are many practical "how-to" volumes available, too few attempt to explain the development of China's foreign-investment regulatory regime in terms of legal culture and practice. Yan Wang's interesting contribution attempts to fill this gap. Sponsored by the East Asian Economic and Business Series of the European Institute of Japanese Studies, her book addresses China's foreign-investment law in light of historical, policy, and legal-culture conditions. Her opening chapter sets forth the broad contours of legal reform in China since 1978, emphasizing the salient points of institutional change while also paying significant attention to legal culture. She goes on to examine the shifting policy contexts for foreign-investment law and the limits these pose for enforcement and predictability. These sections alone make the book worth reading, as Wang deftly navigates among the wide range of secondary sources available on these subjects to provide a useful summary of the institutional and behavioral limitations on the Chinese legal system today. Also provided by way of background is a very short overview of international law regimes against which China's foreign-investment law may be compared. Although it touches usefully on the rule regimes that are associated with the International Centre for the Settlement of Investment Disputes (ICSID) and the Multilateral Investment Guarantee Agency (MIGA), this chapter is a bit too short to add significantly to existing knowledge. The sections that follow address, respectively, the broad objectives and frameworks for China's foreign-investment law regime, investment restrictions and incentives, and the differing mechanisms and policies supporting the management autonomy of foreign investors. A concluding chapter examines the current status of contract law. In contrast to the analysis of institutional and behavioral limits on China's foreign-investment law regime in the previous chapters, the latter sections include much dated material and are somewhat less useful. Wang includes extensive treatment of the "Catalogue Guiding Foreign Investment," issued in 1998. However, a revised "Catalogue" was issued in 2002 and was in the process of public discussion and drafting well before the publication date of Wang's book. In a similar vein, much of Wang's treatment of China's entry into the WTO is written in the future tense, despite the fact that her book was published [End Page 468] after China's accession. A similar problem arises in the discussion of contract law. Wang spends considerable time explaining the PRC's Economic Contract Law and the Foreign Economic Contract Law as though these were still in effect, and then suggests that these "will be replaced" by the [Unified] Contract Law from October 1999—an odd formulation for a book published in 2002. Moreover, the discussion of the [Unified] Contract Law does not include discussion of the critically important interpretation issued in 1999 by the Supreme People's Court addressing a variety of issues on the formation and content of contracts. Finally, Wang's treatment of the "Rev Power" case revisits familiar issues, which have long been superceded by more recent and useful analyses of challenges to arbitration proceedings in China. In the rapidly changing context of China's foreign-investment law regime, these kinds of anomalies are to be expected, and perhaps are unavoidable. No doubt the limitations of copyediting and production prevented more complete updating of the author's material, but these flaws nonetheless weaken the overall utility of the book. The author might have avoided the problems of including dated material by linking these and other time-limited examples to the conceptual points that are made to great effect early in the book. The...

Semi-automated Matlab®-based Software for the analysis of first pass myocardial perfusion images

A MATLAB®-based computer code that analyses the traveltime distribution and performs quality analysis at the pre-inversion stage for 2D transmission experiments is presented. The core tools of this approach are the so-called mean traveltime curves. For any general recording geometry, the user may select any pair of subsets of contiguous sources and receivers. The portion of the domain swept by the implied rays defines a zone of analysis, and for each source (receiver) the outcoming (incoming) ray fan is named a source (receiver) gather. The empirical mean traveltime curves are constructed, for each zone, by assigning the average and the standard deviation of the traveltimes in the gathers to the positions of the sources (receivers).The theoretical expressions assume isotropic homogeneous velocity inside each zone. The empirical counterparts use the observed traveltimes and make no assumptions. Isotropic velocity in each zone is inferred by least-squares fitting of the empirical mean traveltime curves. The user may refine the analysis considering different zones (multi-zone analysis). Initially the whole domain is modelled as a single zone. The procedure compares empirical versus theoretical curves. In addition, residuals can be plotted using source–receiver positions as plane coordinates. The results are used to unravel the possible presence of anomalous gathers, heterogeneities, anisotropies, etc. Depending on the kind of anomalies, velocity estimation and mean time residuals are different in the source and receiver gather curves.This software helps to grasp a better understanding of the data variability before the inversion and provides to the geophysicist an approximate zonal isotropic model and a range of velocity variation that can be used in the inverse problem as a priori information (regularization term). Its use is described through tutorial examples. A guided user interface leads the user through the algorithm steps.

A new transducer holder mechanism for pipe inspection

A new transducer holder mechanism has been designed and fabricated for pipe inspection by cylindrical guided waves. Commercially available ultrasonic transducers have been used to generate compressional ultrasonic waves in the coupling medium. Those waves are converted to cylindrical guided waves in the pipe by the new coupling mechanism. A number of advanced coupling mechanisms developed recently for large plate and pipe inspection require the presence of a coupling fluid between the ultrasonic transducer and the pipe or plate specimen. These mechanisms can be used for inspecting horizontal pipes and plates. The new coupling mechanism presented in this article uses solid material as the coupler and can be used equally well for inspecting horizontal as well as inclined or vertical pipes. The new coupling mechanism has been designed to generate efficiently different Lamb modes in the pipe. The new design has been used to inspect different kinds of anomalies in copper and aluminum pipes. The preliminary results show that a number of Lamb modes, when generated properly by the new coupling mechanism, are very sensitive to the pipe defects. These experimental results along with the new design of the coupling mechanism are presented in this article.

Correlation between the Josephson coupling energy and the condensation energy in bilayer cuprate superconductors

We review some previous studies concerning the intrabilayer Josephson plasmons and present ellipsometric data of the c-axis infrared response of almost optimally doped ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8}.$ The c-axis conductivity of this compound exhibits the same kind of anomalies as that of underdoped ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}.$ We analyze these anomalies in detail and show that they can be explained within a model involving the intrabilayer Josephson effect and variations of the electric field inside the unit cell. The Josephson coupling energies of different bilayer compounds obtained from the optical data are compared with the condensation energies and it is shown that there is a reasonable agreement between the values of the two quantities. We argue that the Josephson coupling energy, as determined by the frequency of the intrabilayer Josephson plasmon, represents a reasonable estimate of the change of the effective c-axis kinetic energy upon entering the superconducting state. It is further explained that this is not the case for the estimate based on the use of the simplest ``tight-binding'' sum rule. We discuss possible interpretations of the remarkable agreement between the Josephson coupling energies and the condensation energies. The most plausible interpretation is that the interlayer tunneling of the Cooper pairs provides the dominant contribution to the condensation energy of the bilayer compounds; in other words that the condensation energy of these compounds can be accounted for by the interlayer tunneling theory. We suggest an extension of this theory, which may also explain the high values of ${T}_{c}$ in the single-layer compounds ${\mathrm{Tl}}_{2}{\mathrm{Ba}}_{2}{\mathrm{CuO}}_{6}$ and ${\mathrm{HgBa}}_{2}{\mathrm{CuO}}_{4},$ and we make several experimentally verifiable predictions.

Characterization of diffraction anomalies in 2-D photonic bandgap structures

This paper deals with transmission anomalies of freestanding two-dimensional bandgap structures, which have found a large application range as filter and guiding structures in communication systems and radioastronomical applications in the far infrared region. The effect appears as a sharp breakdown of the transmission factor in the passband of quadratic patch and slot structures, first revealed by measurements. This paper outlines the numerical confirmation of these effects by computer simulations based on the method of moments combined with the Floquet theorem. The transmission and reflection behavior is examined for different structure geometries, frequency ranges, angle, and polarization of the incident wave also revealing alternative structures suppressing these effects. The modeling with electric and magnetic currents allows the characterization of both patch and slot arrays. Finally, cross shaped structures are examined allowing the complete suppression of this kind of anomalies.

Experimental teratogeny in the tick Hyalomma marginatum marginatum (Acari: Ixodida: Ixodidae): effect of high humidity on embryonic development.

The effect of 90% RH on the embryonic development of Hyalomma marginatum marginatum Koch was investigated at 25 degrees C. Under the influence of this factor, 2.1% dead eggs, 13.0% dead embryos, 6.9% abnormally hatched larvae, 0.2% larvae with malformations, and 77.8% normal larvae appeared. The embryos died during the cleavage of nuclei, the formation of the blastoderm, the formation of the germ band and its metamerization, and the differentiation of the leg anlagen. Egg hatch was also inhibited in various phases. Various kinds of anomalies were observed in larvae of Hyalomma m. marginatum. Most teratological changes (70.8%) occurred within the idiosoma. They were hetromorphose (32.6%), oligomely (15.4%), heterosymely (12.3%), symely (1.5%), atrophy (6.1%), and ectomely (3.1%). Anomalies within the gnathosoma occurred rarely (3.1%). As many as 26.2% larvae had composite anomalies (oligomely, heterosymely, atrophy) together. They contained various structures of the gnathosoma or idiosoma. These anomalies decreased the survival rate of the larvae. The investigations showed that during the formation of the blastoderm, the formation of the germ band and its metamerization the embryos have the largest susceptibility of being affected by high humidity. Some anomalies in specimens collected from nature may develop under influence of unfavorable humidity levels.

Induced Polarization—A Tool for Mapping Titanium-Bearing Placers, Hidden Metallic Objects, and Urban Waste on and Beneath the Seafloor

Recent experiments with a new marine induced polarization (IP) streamer system show that the system is capable of identifying and mapping placer concentrations of titanium-rich minerals on and beneath the seafloor, as well as facies changes in the substrate beneath sandy shoals. Examination of profile data acquired in the Mississippi Sound and Cape Fear shows that the system can also detect ferrous∕non-ferrous metallic objects buried beneath the seafloor which are not discernible by seismic or other geophysical means. The streamer system was originally designed to detect and map polarizeable titanium-bearing placer deposits to at least [Formula: see text] below the sediment-water interface. Recent data show broad phase-shift (a measure of the IP effect) anomalies from titanium sands along the east side of Cat Island (off the coast of Biloxi, Mississippi), and possibly over the now-submerged portion of the PeeDee river on the Atlantic Continental shelf southwest of Cape Fear (North Carolina-South Carolina border). Interspersed in these data are a number of narrow resistivity and coincident resistivity-IP spikes. Both kinds of anomalies show pronounced drops in the already-low resistivity expected for seawater-saturated unconsolidated sediments, but a number of the anomalies also have coincident phase-shift (induced polarization) excursions. These range from less than 5 to over [Formula: see text] across (half-amplitude measurement), but the IP anomalies can be seen [Formula: see text] laterally from their centers. The sources of these anomalies are apparently man-made objects, buried under a veneer of modern sediments. We speculate that the coincident resistivity-IP spikes are caused by shipwrecks, sunken buoys or parts thereof, or other man-made metallic objects lost and later buried beneath inert, modern sediments. The data imply that this marine IP system should be immediately applicable to finding metallic (ferrous and non-ferrous) unexploded ordnance, as well as buried sub-sea cables and pipelines.

Thermal nonequilibrium of the shock-compressed state of polymers realized by 1 GPa shock waves

A thermodynamic theory has been developed to calculate the shock temperature of polymers in the 1 GPa pressure region. For this purpose, the Grüneisen parameter has been calculated based on the available nonlinear shock velocity–particle velocity Hugoniot function for polymers. The calculated large values of the parameter correspond to that of phonon frequencies in the collective motion of polymer molecules, and not to that of the intramolecular vibration frequencies. Then, the equilibrium shock temperature as well as the cold potential energy function is calculated using the calculated Grüneisen parameter and the available nonlinear shock velocity–particle velocity Hugoniot function. Shock temperature and cold potential function have also been calculated using the equilibrium thermodynamic values of the Grüneisen parameter and the specific heat. From these calculations, the following unphysical result has been derived; that is, the cold potential function for these polymers has no minimum value at zero-temperature volume, but monotonically decreases with compression. It is demonstrated that this kind of anomaly can be resolved only when large values of the Grüneisen parameter and the corresponding small values of the specific heat are assumed. These results strongly suggest that the state of the shocked polymers observed in the experiment of μs duration may be the thermodynamic state, which is very different from the thermal equilibrium state in that phonon temperature is sufficiently high but not in equilibrium with molecular vibrational temperature.

Ultrastructural pathology of the sperm flagellum: association between flagellar pathology and fertility prognosis in severely asthenozoospermic men.

An ultrastructural study of spermatozoa in a series of 247 severely asthenozoospermic patients disclosed two kinds of anomalies. The first was dysplasia of the fibrous sheath, a primary defect of spermatozoa with hypertrophy and hyperplasia of the fibrous sheath, associated axonemal anomalies, familial incidence and chronic respiratory disease. The patients could be divided into two subgroups: the complete form (all spermatozoa affected) and the incomplete form (alterations in 70-80% spermatozoa). There were no spontaneous or in-vitro fertilization (IVF) pregnancies. Intracytoplasmic sperm injection (ICSI) in six patients resulted in successful fertilizations, but only two pregnancies were obtained. These features configure a phenotype that suggests a genetic origin. The second anomaly was non-specific flagellar anomaly (NSFA), random secondary flagellar alterations affecting variable numbers of spermatozoa, without respiratory disease or familial incidence. 54 men with NSFA were followed for 2-6 years. Of these, 18 achieved conception, either spontaneous or by means of assisted fertilization, followed by 14 pregnancies and 12 live births. Their sperm motility significantly increased during the follow-up period. In the remaining 36 men motility did not change during the follow-up period and there were no fertilizations or pregnancies. We conclude that in severe asthenozoospermia, ultrastructural examination of spermatozoa has an effective prognostic value, identifying two syndromes with very different flagellar alterations and fertility potentials.

Generalized Nevus Spilus and Nevus Anemicus in a Patient with a Primary Lymphedema: A New Type of Phakomatosis Pigmentovascularis?

Abstract: A patient with a generalized nevus spilus associated with a nevus anemicus and primary lymphedema is reported. We believe that this association does not reflect the merely coincidental coexistence of three kinds of anomalies but that it may represent a new type of phakomatosis pigmentovascularis.

On the Meaningfulness of Optimal Solutions to Scheduling Problems: Can an Optimal Solution be Nonoptimal?

We consider the problem of finding an optimal schedule for jobs on a single machine when there are penalties for both tardy and early arrivals. We point out that if attention is paid to how these penalties are measured, then a change of scale of measurement might lead to the anomalous situation where a schedule is optimal if these parameters are measured in one way, but not if they are measured in a different way that seems equally acceptable. In particular, we note that if the penalties measure utilities or disutilities, or loss of goodwill or customer satisfaction, then these kinds of anomalies can occur, for instance if we change both unit and zero point in scales measuring these penalties. We investigate situations where problems of these sorts arise for four specific penalty functions under a variety of different assumptions. The results of the paper have implications far beyond the specific scheduling problems we consider, and suggest that considerations of scale of measurement should enter into analysis of conclusions of optimality both in scheduling problems and throughout combinatorial optimization.

Comparison of Prominences in Hα and He II 304 Å

In this letter, we bring attention to prominences which show different morphology in Hα and He ii 304 A, as observed simultaneously by BBSO and EIT on board SOHO. Those two lines have been thought to represent similar chromospheric structures although they are formed at significantly different temperatures. We give two examples representing two kinds of anomaly: (1) prominences showing strong Hα emissions in the lower part and strong He ii emissions in the upper part, and (2) erupting prominences showing extensive He ii emission, but nothing in Hα. Our results indicate that a part or the whole of a prominence may be too hot to emit Hα radiation, possibly due to heating or thermal instability. Please note that these are not just two isolated cases, many other prominences show the similar differences in Hα and He ii 304 A.

Anomaly detection: eye movement patterns.

The symptom of a garden path in sentence processing is an important anomaly in the input string. This anomaly signals to the parser that an error has occurred, and provides cues for how to repair it. Anomaly detection is thus an important aspect of sentence processing. In the present study, we investigated how the parser responds to unambiguous sentences that contain syntactic anomalies and pragmatic anomalies, examining records of eye movement during reading. While sensitivity to the two kinds of anomaly was very rapid and essentially simultaneous, qualitative differences existed in the patterns of first-pass reading times and eye regressions. The results are compatible with the proposal that syntactic information and pragmatic information are used differently in garden-path recovery.

Magnetometry of the marine, Ordovician Lockne impact structure, Jämtland, Sweden

Magnetic modelling of the Middle Ordovician Lockne impact crater reveals its morphology and the lack of a magnetically sufficient melt body. Suevite and melt are often strongly remanent and stand out in magnetic surveys. However, exceptions occur, e.g. the Lappajärvi impact structure. From aeromagnetic data a total intensity and a horizontal gradient map were generated. They show a structure with a calm interior. The absence of short wave length anomalies is interpreted to be an indication of the lack of a melt sheet with a prominent magnetic signature. Neither can short wave length anomalies be seen at the expected central uplift of the structure. However, this kind of anomalies are commonly associated with larger impact structures. The modelling produced a bowl-shaped structure which is slightly tilted westwards. This is in good agreement with the field observation of the structure. Based on the absence of magnetic anomalies, together with field observations and drill-core information we are convinced that no prominent melt body was formed in connection with the Lockne impact, despite the size of the structure. This fact may be explained by the type of target. The target material in the Lockne area was seawater and sedimentary strata overlying a crystalline basement. The abundant water in the area possibly contributed to the explosive dispersion of the molten silicates.

Anomalous Ultrasonic Absorption of Liposome Suspensions in the Liquid Crystal Phase

Ultrasonic velocity and absorption of liposome suspensions of dimyristoyl phosphatidylcholine in the liquid crystal phase were measured in the megahertz region, varying the temperature and the size of liposomes. Temperature dependence of ultrasonic properties indicated a critical phenomenon due to the gel-liquid crystal transition at about 24° C, which is characterized by a dip in ultrasonic velocity and an anomalous increase in absorption. However, the anomalous frequency dependence of ultrasonic absorption remained significant even at 35° C where the critical phenomenon almost disappeared. This additional absorption anomaly strongly depended on the size of liposomes. The value of viscosity of multilamellar liposome suspensions estimated from the ultrasonic absorption was inversely proportional to the frequency of the ultrasound and diverged to infinity in the low-frequency limit, while this kind of anomaly was not observed for small unilamellar lipid vesicles. This liposome size dependence indicated clearly that the additional absorption anomaly in multilamellar liposomes was due to the fluctuation of their lamellar structure. The possibility of estimating the content of stacked membrane layers in biological tissue by ultrasonic absorption is discussed based on the ultrasonic measurements of liposomes.

Verification of Uncertain Knowledge-Based Systems: An Empirical Verification Approach

A number of different tests and approaches are developed to determine the existence of potential anomalies in rule-based systems that employ MYCIN uncertainty factors (weights). First, the distribution of weights is compared to other systems' distributions and weights are investigated as to their individual meanings, to determine whether any weights are unusual. Second, there is increasing evidence that people are not “good” at developing weights on rules, building in symmetries and redundancies that signal “usual” assumptions about the underlying probabilities. Accordingly, weight symmetries generated from rule pairs are analyzed to determine the existence of anomalies. Third, typically rule-based tools have been developed for application in specific domains, such as medicine. Unique aspects of those domains may limit application of the tools to other domains. Finally, ad hoc, rule-based approaches are suboptimal, and alternative formal probability approaches, such as Bayes' nets, more fully specify the probabilistic nature of knowledge. The paper is part of the empirical verification literature, where verification is done on an actual system and the system provides data that indicates the kinds of anomalies that can be expected. A case study is used to illustrate each of the verification tests and concerns.