Notable Anomalies Research Articles

Socio-Economic Implications of Snow Cover Area in the Upper Indus Basin

The Indus River, one of the principal waterways in Asia, specifically the Indian Subcontinent, originates from the Himalayan Region and Qinghai-Tibet Plateau. Understanding snow cover dynamics is one of the most vital components for effective hydrological resource management and assessing the impacts of local, regional, and global climatic variations. Variations in the radiation of snow microstructures and snowpacks have profound socio-economic and environmental consequences, affecting agricultural productivity, reservoir supply for factories, environmental sustainability, governance of land resources, and overall community resilience. Fluctuations in snowmelt patterns can lead to water shortages or surplus, influencing food security and economic stability in a country largely dependent on agriculture. Utilizing Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data, this study assesses the implications of Snow Cover Area (SCA) on water security and livelihood of agricultural-related sectors. A comparative analysis of snow cover reveals a shifting trend in the accumulation period, with notable anomalies affecting the agricultural output, which affects the household income related to the agricultural sector. This research underscores the necessity of adapting water management strategies to align with evolving snow cover dynamics to mitigate potential socio-economic risks.

Change in precipitation pattern over South Asia in response to the trends in regional warming and free-tropospheric aerosol loading

Spatial and temporal shifts in rainfall patterns over South Asia and the adjoining Seas during the pre-monsoon season have been observed over the past 2 decades from 2000 to 2019. Aerosol particles suspended above the boundary layer are a contributing factor to these changes. These particles not only alter cloud characteristics, but also diminish the lapse rate, thereby suppressing convective activity, leading to precipitation anomalies. Over the past 2 decades, high-rainfall regions have experienced declining rainfall, while low-rainfall regions have received increased rainfall. Coinciding with notable anomalies in precipitation, contrasting trends in aerosol optical depth, particularly due to absorbing aerosols in the elevated regions of the atmosphere, are seen. Apart from aerosols, several factors are considered that are critical in modifying precipitation patterns over the study region, such as water vapor content, convective processes, and lower-level relative humidity. We observed a potential transport of excess water vapor by ambient circulation from the oceanic regions having reduced rain, such as Bay of Bengal and the Arabian Sea, to higher latitudes enabling precipitation anomaly at distant locations.

Magnetic order induced by magnetic impurities in the Haldane chain compound SrNi2V2O8

Understanding the topological properties of Haldane spin systems offers promising avenues for exploring exotic quantum phases. We investigate the impact of S = 5/2 Mn2+ impurities on the magnetic properties of SrNi2V2O8, a well-known Haldane spin gapped system. Structural characterizations of SrNi2-xMnxV2O8 (x = 0.05, 0.15, 0.30 and 0.60) through Rietveld analyses of X-ray diffraction data confirm the preservation of the I41cd space group for all studied x , along with a preferential insertion of Mn2+ ions into Ni2+ sites. Magnetic susceptibility and magnetization data unveil a magnetic transition occurring in the temperature range of T = 93–99.3 K for x = 0.05–0.60. Dielectric data evince the absence of coupling between magnetic and ferroelectric phases. Notably, the magnetic ordering temperature varies little over a wide range of Mn concentrations, while notable anomalies are observed at x = 0.15. This peculiar behavior suggests that, across low-to-high concentrations, disorder-induced magnetic moments compete with the formation of spin singlets between the nearest Mn2+ impurities, which cancel out the magnetic moments.

Strong Eddy Kinetic Energy Anomalies Induced by Baroclinic Instability in the Southwest Region of the Kerguelen Plateau, East Antarctica

AbstractEddy activity is particularly prominent in the Southern Ocean due to the instabilities of the Antarctic Circumpolar Current, which plays a critical role in energy transport of the global ocean. In this study, a systematic energetics analysis framework is employed to investigate notable anomalies of an intensified Eddy Kinetic Energy (EKE) event observed in the southwest region of the Kerguelen Plateau in the Indian sector of the Southern Ocean in 2017, utilizing a reanalysis product. The EKE anomalies, presenting across all depths, emerged in April, peaked during the austral winter, and persisted into the subsequent summer. Energetics analysis indicates that the pronounced EKE anomalies are primarily determined by baroclinic instability, with distinct governing mechanisms at the surface and in the internal ocean. The anomalous intrusion of warm Circumpolar Deep Water intensified the baroclinic energy conversion in the subsurface, contributing significantly to the EKE anomalies. Moreover, strong anomalous wind‐induced Ekman pumping served to amplify the lifting of isopycnals, which enhanced the baroclinic instability and subsequently intensified the EKE anomalies. This study sheds new light on underlying mechanisms governing local polar dynamics and provides insights into the intricate interaction between ocean dynamics and energy distribution in the Antarctic region.

Anthropogenic gadolinium in the Tone River (Japan): an update showing a 7.7-fold increase from 1996 to 2020

BackgroundAnthropogenic gadolinium (Gd), originating from Gd-based contrast agents (GBCAs) used in magnetic resonance imaging (MRI), is widely identified in the aquatic environment with concerns about toxicity and accumulation. We aimed to present new data on anthropogenic Gd in the Tone River, which has the largest drainage area in Japan, and then to compare the current data with those obtained in 1996.MethodsThe water samples were collected on August 9−10, 2020, at 15 different locations of the Tone River in Japan. The concentrations of the rare earth elements (REEs) were measured by inductively coupled plasma-mass spectrometry and normalized to Post-Archean Australian Shale to construct shale-normalized REE patterns. The degree of Gd-anomaly was defined as the percentage of anthropogenic Gd to the geogenic background and used to compare the water samples from different locations. Pearson’s correlation coefficients were calculated.ResultsAll the samples displayed positive Gd anomalies. The Gd-anomaly ranged from 121 to 6,545% and displayed a repeating decrease-and-increase trend. The Gd-anomaly showed strong positive correlations to the number of hospitals (r = 0.88; p < 0.001) and their MRI units (r = 0.89; p < 0.001).ConclusionsOur study revealed notable anomalies of Gd concentrations in river water in Japan, with strong positive correlations to the number of major hospitals and their MRI units. Compared with the previous report in 2000, the Gd-anomaly in Tone River increased from 851% (sampled in 1996) to 6,545%, i.e., 7.7 times, reflecting the increased use of GBCAs in hospitals.Relevance statementNotable Gd concentration anomalies in river water in Japan were observed. This result underlines the importance of more extensive research on anthropogenic gadolinium, and investigations of risks to human health as well as the development of effective removal technologies may be necessary.Key points• All water samples from Tone River displayed positive Gd anomalies.• The Gd anomalies increased to 7.7 times higher over the past 24 years.• Correlations between Gd values and the number of hospitals and MRI units were observed.Graphical

SWOT Level 2 Lake Single-Pass Product: The L2_HR_LakeSP Data Preliminary Analysis for Water Level Monitoring

The Surface Water and Ocean Topography (SWOT) mission, launched in December 2022, aims to address the crucial environmental goal of water monitoring to support preparedness for extreme events and facilitate adaptation to climate change on global and local scales. This mission will provide a comprehensive inventory of worldwide water resources, lakes, reservoir storage, and river dynamics. In this work, we carried out a preliminary assessment of SWOT’s Lake product Level 2 version 1.1, also known as “L2_HR_LakeSP”. The analysis was performed across six diverse lakes on three continents, revealing an average median bias of 0.08 m with respect to the considered reference, after suitable outlier removal. An overall precision of 0.22 m was found, combined with an average correlation of 68% between SWOT and reference time series. Moreover, the accuracy varied in the considered six lakes, since biases up to some decimeters were found for some of them; they could be due to residual inconsistencies between the vertical reference frame of SWOT and that of the considered reference. In summary, the first analysis of the “L2_HR_LakeSP” product, Version 1.1, demonstrated the promising potential of SWOT for monitoring seasonal variations in water levels. Nevertheless, notable anomalies were found in the water masks, particularly in higher latitudes, suggesting potential difficulties in accurately delineating water bodies in those regions. Additionally, a discernible reduction in accuracy was observed towards the end of the monitoring period. These preliminary findings indicate some issues that should be addressed in future investigations about the quality and potential of SWOT’s lake products for advancing our understanding of global water dynamics.

Modulation of the impact of winter-mean warm Arctic-cold Eurasia pattern on Eurasian cold extremes by the subseasonal variability

Utilizing ERA5 data, this study provides evidence that both the winter-mean state and subseasonal variability (SSV) of the warm Arctic-cold Eurasia (WACE) pattern significantly influence the frequency of cold extremes in Eurasia. The positive phase of winter-mean WACE (WACEMean) or a stronger SSV of WACE (WACESSV) corresponds to a higher occurrence of cold extremes over central Eurasia and East Asia. Furthermore, the study reveals that the impact of WACEMean on the cold extremes is modulated by WACESSV. During years characterized by a positive WACEMean and enhanced WACESSV, the associated winter-mean anticyclonic anomalies, combined with amplified subseasonal circulation fluctuations over the northern Eurasia continent, contribute to a significant increase in the blocking frequency over the Ural–Siberia region. This, in turn, contributes to an intensified occurrence of cold extremes in central Eurasia and East Asia. In contrast, during the years with a positive WACEMean but reduced WACESSV, in the absence of significant changes in the subseasonal circulation fluctuations, the winter-mean anticyclonic anomalies over the northern Eurasia continent do not exert a significant impact on Ural–Siberian blocking frequency by themselves. Consequently, there are no notable anomalies in the frequency of cold extremes over central Eurasia and East Asia. Finally, this study reveals that the differences in the distribution of the frequency anomalies in the blocking between the two sets of years are attributed to the constructive and destructive superposition of anomalies in subseasonal circulation fluctuations related to the WACEMean and WACESSV.

Toxic effects of the insecticide tolfenpyrad on zebrafish embryos: Cardiac toxicity and mitochondrial damage.

Tolfenpyrad, a highly effective and broad-spectrum insecticide and acaricide extensively utilized in agriculture, presents a potential hazard to nontarget organisms. This study was designed to explore the toxic mechanisms of tolfenpyrad on zebrafish embryos. Between 24 and 96 h after exposure of the fertilized embryos to tolfenpyrad at concentrations ranging from 0.001 to 0.016 mg/L (96 h-LC50 = 0.017 mg/L), lethal effects were apparent, accompanied with notable anomalies including pericardial edema, increased pericardial area, diminished heart rate, and an elongated distance between the venous sinus and the arterial bulb. Tolfenpyrad elicited noteworthy alterations in the expression of genes pertinent to cardiac development and apoptosis, with the most pronounced changes observed in the cardiac development-related genes of bone morphogenetic protein 2b (bmp2b) and p53 upregulated modulator of apoptosis (puma). The findings underscore that tolfenpyrad induces severe cardiac toxicity and mitochondrial damage in zebrafish embryos. This data is imperative for a comprehensive assessment of tolfenpyrad risks to aquatic ecosystems, particularly considering the limited knowledge regarding its detrimental impact on aquatic vertebrates.

NGC 2022, a case study of a multiple-shell planetary nebula

ABSTRACT We present a detailed study of the physical properties, history of mass loss, and chemical abundances of the planetary nebula NGC 2022. New imaging observations obtained with the OAJ/JAST80 and NOT/ALFOSC confirm the presence of a faint ∼88 arcsec halo surrounding a double-layered elliptical structure that consists of a bright 21.4 × 16.7 arcsec inner shell and a 32 arcsec diameter envelope. The long-slit high-dispersion echelle observations obtained with MES on the OAN-SPM 2.1-m telescope can be well described by a shape model with expansion velocities of 43 ± 3 and 34 ± 3 km s−1 along the major and minor axes of the elliptical inner shell, respectively. In addition, a deep long-slit high-dispersion echelle observation made with the KPNO 4-m telescope detected line-splitting in the faint halo, revealing an expansion velocity of 15.5 ± 2 km s−1. We have also used new intermediate-dispersion optical spectra with the NOT, complemented with IUE data, to study the chemical abundances of each shell. The abundances of the three shells are typical of a Type II in the Peimbert classification of PNe and do not exhibit any notable anomalies. Finally, we estimate the total mass of NGC 2022 to be ≈0.9 M⊙, which consists of 0.64 M⊙ from the CSPN and 0.1, 0.11, and 0.1 × $f_{\mathrm{halo}}^{1/2}$ M⊙ from the ionized inner shell, outer shell, and halo, respectively.

How long should a patron ban be: an examination of police-imposed barring notice records in Western Australia

PurposePatron banning is widely used in response to disorderly behaviours in/around licensed venues, but there has been limited analysis of specific policies. This paper explores key findings in relation to police-imposed barring notices in Western Australia (WA).Design/methodology/approachWA Police provided de-identified data for 4,023 barring notices imposed between 2011 and 2020 and offender records for each recipient, to 30 June 2020. The data were analysed to identify patterns and trends in relation to ban length, recipient type and associated offending.FindingsMean ban lengths increased across the period (from 4.46 months in 2015 to 6.82 months in 2019). Longer initial bans (of 6–12 months) were associated with a lower likelihood of a subsequent ban – with each additional month associated with an 11.4% increase in the likelihood of not receiving a second ban. Across the dataset, some notable anomalies were identified for individuals categorised as prolific offenders.Originality/valueResearch examining the effects of patron banning is limited but, to date, has generally not supported presumptions of improved patron behaviour. WA adopts an individualised approach to barring notice lengths, following review of the incident and offender. The findings suggest that, while barring policy is appropriate, a number of operational refinements can help WA Police to optimise their behavioural effect/s.

A Comparative Study of Geoelectric Signals Possibly Associated with the Occurrence of Two Ms &gt; 7 EQs in the South Pacific Coast of Mexico

During past decades, several studies have suggested the existence of possible seismic electric precursors associated with earthquakes of magnitude . However, additional analyses are needed to have more reliable evidence of pattern behavior prior to the occurrence of a big event. In this article we report analyses of self-potential records during approximately two years in three electro-seismic stations in Mexico located at Acapulco, Guerrero; Petatlán, Guerrero and Pinotepa Nacional, Oaxaca. On 18 April 2014 an earthquake occurred near our Petatlán station. Our study shows two notable anomalies observed in the behavior of the Fourier power spectrum of for ultra low frequency ULF-range, and the transition of the -exponent of the detrended fluctuation analysis of the time series from uncorrelated to correlated signals. These anomalies lasted approximately three and a half months before the main shock. We compare this electric pattern with another electric signal we reported associated with an that occurred on 14 September 1995 at Guerrero state, Mexico. Our characterization of the anomalies observed in both signals point out similar features that enrich our knowledge about precursory phenomena linked to the occurrence of earthquakes of magnitude .

Modeling Satellite Gravity Gradient Data to Derive Density, Temperature, and Viscosity Structure of the Antarctic Lithosphere

AbstractIn this study we combine seismological and petrological models with satellite gravity gradient data to obtain the thermal and compositional structure of the Antarctic lithosphere. Our results indicate that Antarctica is largely in isostatic equilibrium, although notable anomalies exist. A new Antarctic Moho depth map is derived that fits the satellite gravity gradient anomaly field and is in good agreement with independent seismic estimates. It exhibits detailed crustal thickness variations also in areas of East Antarctica that are poorly explored due to sparse seismic station coverage. The thickness of the lithosphere in our model is in general agreement with seismological estimates, confirming the marked contrast between West Antarctica (&lt;100 km) and East Antarctica (up to 260 km). Finally, we assess the implications of the temperature distribution in our model for mantle viscosities and glacial isostatic adjustment. The upper mantle temperatures we model are lower than obtained from previous seismic velocity studies. This results in higher estimated viscosities underneath West Antarctica. When combined with present‐day uplift rates from GPS, a bulk dry upper mantle rheology appears permissible.

Joint Bayesian analysis of large angular scale CMB temperature anomalies

Cosmic microwave background measurements show an agreement with the concordance cosmology model except for a few notable anomalies: Power Suppression, the lack of large scale power in the temperature data compared to what is expected in the concordance model, and Cosmic Hemispherical Asymmetry, a dipolar breakdown of statistical isotropy. An expansion of the CMB covariance in Bipolar Spherical Harmonics naturally parametrizes both these large-scale anomalies, allowing us to perform an exhaustive, fully Bayesian joint analysis of the power spectrum and violations of statistical isotropy up to the dipole level. Our analysis sheds light on the scale dependence of the Cosmic Hemispherical Asymmetry. Assuming a scale-dependent dipole modulation model with a two-parameter power law form, we explore the posterior pdf of amplitude A(l = 16) and the power law index α and find the maximum a posteriori values A*(l = 16) = 0.064 ± 0.022 and α* = −0.92 ± 0.22. The maximum a posteriori direction associated with the Cosmic Hemispherical Asymmetry is (l,b) = (247.8o, −19.6o) in Galactic coordinates, consistent with previous analyses. We evaluate the Bayes factor BSI−DM to compare the Cosmic Hemispherical Asymmetry model with the isotropic model. The data prefer but do not substantially favor the anisotropic model (BSI−DM=0.4). We consider several priors and find that this evidence ratio is robust to prior choice. The large-scale power suppression does not soften when jointly inferring both the isotropic power spectrum and the parameters of the asymmetric model, indicating no evidence that these anomalies are coupled.

Chemical evidence for differentiation, evaporation and recondensation from silicate clasts in Gujba

The silicate and metal clasts in CB chondrites have been inferred to form as condensates from an impact-generated vapor plume between a metal-rich body and a silicate body. A detailed study of the condensation of impact-generated vapor plumes showed that the range of CB silicate clast compositions could not be successfully explained without invoking a chemically differentiated target. Here, we report the most comprehensive elemental study yet performed on CB silicates with 32 silicate clasts from nine slices of Gujba analyzed by laser ablation inductively coupled plasma mass spectrometry for 53 elements. Like in other studies of CBs, the silicate clasts are either barred olivine (BO) or cryptocrystalline (CC) in texture. In major elements, the Gujba silicate clasts ranged from chondritic to refractory enriched. Refractory element abundances ranged from 2 to 10×CI, with notable anomalies in Ba, Ce, Eu, and U abundances. The two most refractory-enriched BO clasts exhibited negative Ce anomalies and were depleted in U relative to Th, characteristic of volatilization residues, while other BO clasts and the CC clasts exhibited positive Ce anomalies with excess U (1–3×CI), and Ba (1–6×CI) anomalies indicating re-condensation of ultra-refractory element depleted vapor. The Rare Earth Elements (REE) also exhibit light REE (LREE) enrichment or depletion in several clasts with a range of (La/Sm)CI of 0.9–1.8. This variation in the LREE is essentially impossible to accomplish by processes involving vapor–liquid or vapor–solid exchange of REE, and appears to have been inherited from a differentiated target. The most distinctive evidence for inherited chemical differentiation is observed in highly refractory element (Sc, Zr, Nb, Hf, Ta, Th) systematics. The Gujba clasts exhibit fractionations in Nb/Ta that correlate positively with Zr/Hf and span the range known from lunar and Martian basalts, and exceed the range in Zr/Hf variation known from eucrites. Variations of highly incompatible refractory elements (e.g., Th) against less incompatible elements (e.g., Zr, Sr, Sc) are not chondritic, but exhibit distinctly higher Th abundances requiring a differentiated crust to be admixed with depleted mantle in ratios that are biased to higher crust/mantle ratios than in a chondritic body. The possibility that these variations are due to admixture of refractory inclusion-debris into normal chondritic matter is raised but cannot be definitively tested because existing “bulk” analyses of CAIs carry artifacts of unrepresentative sampling. The inferences drawn from the compositions of Gujba silicate clasts, here, complement what has been inferred from the compositions of metallic clasts, but provide surprisingly detailed insight into the structure of the target. Evidence that metal and silicate in CB chondrites both formed from impact-generated vapor plumes, taken together with recent work on metallic nodules in E chondrites, and on ordinary chondrites, indicates that chondrule formation occurs by this mechanism quite widely. However, the nature of the impact on the CB body is quite different than the popular conceptions of impact of partially or wholly molten chondritic bodies and the younger (5Ma) age of CB chondrules is consistent with origin in a disk with more evolved targets and impactors gravitationally perturbed by nascent planets.

Investigation of chiral phases near helical ordering temperature in MnSi

Chiral modulation crossovers and phase transitions of MnSi in the vicinity of the long-range magnetic ordering temperature are investigated. Notable anomalies in specific heat as a function of magnetic fields that directly correspond to the speculated chiral modulations in the precursor region are observed. The magneto-thermal (H–T) phase diagram reveals the existence of repulsive, attractive, and confined skyrmion phases. Resistivity analysis suggests strong electron–magnon coupling as well as the possibility of strong electron correlations in MnSi supported by the Kadowaki–Woods ratio (), which is close to that of moderate heavy Fermion metals.

CORRUPTION AND DEVELOPMENT: EXPLAINING THE EVIDENCE*

This paper presents a theoretical account of some empirical observations about the relationship between public sector corruption and economic development. These observations include both important regularities and notable anomalies which indicate that there is rather more to this relationship than one is often led to believe. The paper brings together some previous work for the purpose of providing a unified account of the issues involved within the context of a single analytical framework. These include the causality between corruption and development, the persistence of corruption and poverty, the diversity of corruption across countries and the differential impact of corruption in different economies.

Effect of pressure on the band gap and the local FeO6environment in BiFeO3

BiFeO${}_{3}$ exhibits a complex phase-transition sequence under pressure associated with changes in octahedron tilts and displacements of Bi${}^{3+}$ and Fe${}^{3+}$ cations. Here, we investigate the local structure of Fe${}^{3+}$ as a function of pressure through absorption crystal-field spectroscopy in the 0--18 GPa range. We focus on the influence of phase transitions on the Fe${}^{3+}$ off-center displacement through the energy ($E$) and oscillator strength (${f}_{d\ensuremath{-}d}$) of the ${}^{4}$T${}_{1}$ and ${}^{4}$T${}_{2}$ Fe${}^{3+}$ (3${d}^{5}$) bands observed below the band gap (${E}_{\mathrm{gap}}$ $=$ 2.49 eV) at 1.39 and 1.92 eV, respectively, at ambient conditions. Pressure induces linear redshift of both ${}^{4}$T${}_{1}$ and ${}^{4}$T${}_{2}$ bands, consistent with the compression of the FeO${}_{6}$ octahedron under pressure. On the other hand, the transition oscillator strength (${f}_{d\ensuremath{-}d}=3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$), enabled by both the exchange mechanism and the off-center Fe${}^{3+}$ distortion, slightly increases with pressure. The absence of notable anomalies in the variation of $E$($P$) and ${f}_{d\ensuremath{-}d}$($P$) through the phase sequence from the ferroelectric rhombohedral $R$3$c$ phase to the nonpolar orthorhombic Pnma phase suggests a persisting off-center position of the Fe${}^{3+}$. While this local polarity is correlated and expected in the ferroelectric $R$3$c$ phase, its presence in the high-pressure nonpolar Pnma phase indicates the presence of local polar instabilities.

Crustal shear wave velocity structure of the western United States inferred from ambient seismic noise and earthquake data

Surface wave dispersion measurements from ambient seismic noise and array‐based measurements from teleseismic earthquakes observed with the EarthScope/USArray Transportable Array (TA) are inverted using a Monte Carlo method for a 3‐D VS model of the crust and uppermost mantle beneath the western United States. The combination of data from these methods produces exceptionally broadband dispersion information from 6 to 100 s period, which constrains shear wave velocity structures in the crust and uppermost mantle to a depth of more than 100 km. The high lateral resolution produced by the TA network and the broadbandedness of the dispersion information motivate the question of the appropriate parameterization for a 3‐D model, particularly for the crustal part of the model. We show that a relatively simple model in which VS increases monotonically with depth in the crust can fit the data well across more than 90% of the study region, except in eight discrete areas where greater crustal complexity apparently exists. The regions of greater crustal complexity are the Olympic Peninsula, the MendocinoTriple Junction, the Yakima Fold Belt, the southern Cascadia back arc, the Great Central Valley of California, the Salton Trough, the Snake River Plain, and the Wasatch Mountains. We also show that a strong Rayleigh‐Love discrepancy exists across much of the western United States, which can be resolved by introducing radial anisotropy in both the mantle and notably the crust. We focus our analysis on demonstrating the existence of crustal radial anisotropy and primarily discuss the crustal part of the isotropic model that results from the radially anisotropic model by Voigt averaging. Model uncertainties from the Monte Carlo inversion are used to identify robust isotropic features in the model. The uppermost mantle beneath the western United States is principally composed of four large‐scale shear wave velocity features, but lower crustal velocity structure exhibits far greater heterogeneity. We argue that these lower crustal structures are predominantly caused by interactions with the uppermost mantle, including the intrusion and underplating of mafic mantle materials and the thermal depression of wave speeds caused by conductive heating from the mantle. Upper and middle crustal wave speeds are generally correlated, and notable anomalies are inferred to result from terrane accretion at the continental margin and volcanic intrusions.

End-element anomalies in medical ultrasonic piezo-composite arrays

Piezoelectric composites are commonly used in medical diagnostic ultrasonic imaging arrays. The performance of the array elements at either end of the array can differ from that of array elements away from the ends. There is some general understanding about the origin of these effects (such as different acoustic impedance), and some standard compensatory designs exist (such as adding unused array elements further on the end than the last used array element). This work seeks to elucidate the origins of these end-element anomalies and to propose corresponding design changes. A commercially produced array with notable end-element anomalies is examined as a case study. Results from experiments and finite element analysis indicate that, in the presence of a stiffness discontinuity within the composite (such as poled elements adjacent to unpoled ones), a secondary wave that propagates laterally through the composite may be generated during the receive transduction. This wave appears to cause the anomalous behavior observed in the signals and metrics of the end elements. Changing the electrical loading of an element and poling the unused, previously unpoled elements are explored as anomaly-mitigating design alterations. The latter of these 2 initially appears to be the more effective solution.

The WTO, Science, and the Environment: Moving Towards Consistency

Governments are increasingly using taxes to address a variety of environmental concerns. World Trade Organization (WTO) rules recognize that, like regulatory instruments, governments may use taxes for protectionist purposes. The rules are designed to prevent protectionist behaviour while allowing use of such instruments for genuine purposes such as environmental protection. Interestingly, however, there are some notable anomalies in the rules arising from differential evidentiary requirements in different situations. First, the rules are different depending upon whether a country's measure aims to protect on one hand human, animal, or plant health; or on the other, the environment. Second, the rules are stricter where a country's measure takes the form of a regulation than where it takes the form of a tax. The article argues that there is no principled rationale for the differential evidentiary requirements by instrument (regulation versus taxes) or area (health versus environment) but finds that there may be both a historical and political economy explanation. It also discusses the desirability for consistency in WTO law across instruments and risk-related policy areas.