Groundwater salinisation on atoll islands after storm‐surge flooding: modelling the influence of central topographic depressions

Fresh groundwater lenses (FGLs) are of utmost importance for human survival on small and isolated atolls. This article examines saline damage to atoll FGLs from wave washover caused by storm surge and studies the particular influence of central topographic depressions (CTDs). We model storm surge over atoll islets of contrasting widths (400 and 800 m), both with and without CTDs of various sizes. Three key findings emerge. First, under equilibrium undisturbed conditions, the CTD slightly reduces the size of the FGL compared to atoll islets without this feature. Second, during marine flooding, prior saturated conditions at the base of a CTD impede seawater infiltration into the substrate, thereby limiting saline damage in that location. Third and most crucial, however, the amount of salt accumulated within the CTD is significant, ranging from 2 to 10 times higher than the net subsurface infiltration during the period of the storm inundation.     

American Symbolism in Intercultural Communication: An Animosity/Ethnocentrism Perspective on Intergroup Relations and Consumer Attitudes

What leads to acceptance versus rejection of messages that represent one's own culture/in‐group, or a foreign culture/out‐group? We investigate how symbols in mass communication might be used to overcome biases toward in‐group and out‐group messages. We experimentally study these effects across countries representing varying levels of consumer ethnocentrism (which relates to attitudes about one's own country, or in‐group) and country‐specific animosity (which relates to attitudes about a particular foreign country, or out‐group). We select 4 countries based on varying levels of ethnocentrism and U.S.‐focused animosity. Using a Social Identity perspective, we find support for asymmetries of response regarding in‐group preference and out‐group discrimination within the context of U.S. and indigenous cultural representations in the form of symbols and brands.     

Microcosm investigations of phthalate behaviour in sewage treatment biofilms

Discharge from sewage works has been shown to be an important source of phthalates into the environment which is of major concern because some are toxic, suspected endocrine disruptors and recalcitrant. Laboratory trickle filter microcosms (continuous and re-circulating flow) were constructed and operated to investigate the biodegradation and adsorption of phthalates and also to isolate phthalate degrading microorganisms. It was found that adsorption was critical for the removal of both DEP (77.5%) and DEHP (55.7%) in continuous flow microcosms. The proportion of phthalates removed by biodegradation in the continuous flow microcosms was estimated. Re-circulating flow microcosms improved the removal of DEHP compared to continuous flow microcosms. Microcosm biofilm used for an enrichment culture on phthalate media isolated a varied group of microbes including Gram negative and Gram positive bacteria, yeasts and fungi. Bacteria species with all the necessary enzymes to degrade phthalic acid were isolated.     

Chemical contaminants, health indicators, and reproductive biomarker responses in fish from the Colorado River and its tributaries

Common carp (Cyprinus carpio), black bass (Micropterus spp.), and channel catfish (Ictalurus punctatus) were collected from 14 sites in the Colorado River Basin (CRB) to document spatial trends in accumulative contaminants, health indicators, and reproductive biomarkers. Organochlorine residues, 2,3,7,8-tetrachlorodibenzo-p-dioxin-like activity (TCDD-EQ), and elemental contaminants were measured in composite samples of whole fish, grouped by species and gender, from each site. Selenium (Se) and mercury (Hg) concentrations in fish were elevated throughout the CRB, and pesticide concentrations were greatest in fish from agricultural areas in the Lower Colorado River and Gila River. Selenium concentrations exceeded toxicity thresholds for fish (>1.0 microg/g ww) at all CRB sites except the Gila River at Hayden, Arizona. Mercury concentrations were elevated (>0.1 microg/g ww) in fish from the Yampa River at Lay, Colorado; the Green River at Ouray National Wildlife Refuge (NWR), Utah and San Rafael, Utah; the San Juan River at Hogback Diversion, New Mexico; and the Colorado River at Gold Bar Canyon, Utah, Needles, California, and Imperial Dam, Arizona. Concentrations of p,p'-DDE were relatively high in fish from the Gila River at Arlington, Arizona (>1.0 microg/g ww) and Phoenix, Arizona (>0.5 microg/g ww). Concentrations of other formerly used pesticides including toxaphene, total chlordanes, and dieldrin were also greatest at these two sites but did not exceed toxicity thresholds. Currently used pesticides such as Dacthal, endosulfan, gamma-HCH, and methoxychlor were also greatest in fish from the Gila River downstream of Phoenix. Total polychlorinated biphenyls (PCBs; >0.11 microg/g ww) and TCDD-EQs (>5 pg/g ww) exceeded wildlife guidelines in fish from the Gila River at Phoenix. Hepatic ethoxyresorufin O-deethylase (EROD) activity was also relatively high in carp from the Gila River at Phoenix and in bass from the Green River at Ouray NWR. Fish from some sites showed evidence of contaminant exposure as indicated by fish health indicators and reproductive biomarker results. Multiple health indicators including altered body and organ weights and high health assessment index scores may be associated with elevated Se concentrations in fish from the Colorado River at Loma, Colorado and Needles. Although grossly visible external or internal lesions were found on most fish from some sites, histopathological analysis determined many of these to be inflammatory responses associated with parasites. Edema, exophthalmos, and cataracts were noted in fish from sites with elevated Se concentrations. Intersex fish were found at seven of 14 sites and included smallmouth bass (M. dolomieu), largemouth bass (M. salmoides), catfish, and carp and may indicate exposure to endocrine disrupting compounds. A high proportion of smallmouth bass from the Yampa River at Lay (70%) was intersex but the cause of this condition is unknown. Male carp, bass, and catfish with low concentrations of vitellogenin were common in the CRB. Comparatively high vitellogenin concentrations (>0.2 mg/mL) were measured in male bass from the Green River at Ouray NWR and the Colorado River at Imperial Dam and indicate exposure to estrogenic or anti-androgenic chemicals. Anomalous reproductive biomarkers including low GSI and gonadal abnormalities (calcifications, edema, and parasites) observed in fish downstream of Phoenix are likely related to the poor water-quality of the Gila River in this area.     

Experimental solid–liquid equilibria and solid formation kinetics for carbon dioxide in methane for LNG processing

In cryogenic liquefaction processes, CO₂ poses a solid-formation risk even in trace concentrations. We present solid–fluid equilibrium (SFE) data for CO₂ in liquid methane at CO₂ concentrations from (52 to 500) ppm, extending the available data and indicating that models tuned to existing data over predict the solubility of CO₂ at LNG storage temperatures (~112 K) by nearly a factor of 3. The new data are used to improve the SFE model in the ThermoFAST software package. The formation kinetics of CO₂ solids in liquid methane are elucidated at conditions relevant to cryogenic gas processing. Repeated, ramped-temperature formation measurements provide a statistical basis for quantifying solidification risk. Nucleation rates extracted from the ramped-temperature data, consistent with those measured at fixed temperature, were used to extract parameters describing CO₂ solid formation in methane. These results significantly improve the ability to predict CO₂ solid formation risk in cryogenic natural gas processing.     

EXAMINATION OF FERMENTED CIDER VOLATILES FOLLOWING CONCENTRATION ON THE POROUS POLYMER PORAPAK Q

The volatiles in the air above cider have been collected on Porapak Q, regenerated and examined by capillary column gas chromatography and gas chromatography-mass spectrometry. The composition of the extract differs from that obtained from distillation and extraction techniques giving increased relative concentrations of non-polar components. 105 peaks were detected and 59 components identified. Several of these have not previously been reported in ciders.     

Zusammenhänge zwischen Eigenschaften,Rohstoffkomponenten und dem Dichteprofil von Spanplatten

The majority of industrially produced particleboards are sanded before delivery. Sanding losses have to be kept at a minimum and board symmetry must be maintained, particularly in higher density surfacelayers. Stillunknown, however, ishow sanding losses vary per side and how board symmetry and board properties are affected. Laboratory model boards were used to show how density profiles, abrasíon thickness and weight precentage can be determined for every side by comparison before and after sanding. Thus for industrial production accurate sanding control is possible and, when testing bending strength and MOE, an estimation of the changes in these properties.     

Analytical Studies of Interaction between Mobility Models and Single-Multi Paths Routing Protocols in Mobile Ad Hoc Networks

Mobile ad hoc networks (MANETs) will play a vital role in civilian and military applications where users move around and share information with each other. The movement of users varies depending on the environment, e.g. people may move randomly in different directions (Random Waypoint and Gauss Markov mobility models); or walk, run and drive in two directions in the street (Manhattan Mobility Model); or move as a group (Reference Point Group Mobility model). The interaction between mobility patterns and routing protocols contributes significantly to vary the overall network performance. We build an analytical framework that shows an analysis structure for the overall network performance test. In this framework, we first compare the properties of the mobility models that are designated for MANETs. Second, we measure single path (proactive and reactive) and multipath (proactive and reactive) routing protocols across the mobility models by tuning into TCP and CBR traffic individually. Finally, we examine the performance of each routing protocol across mobility models and discuss the possibility of interaction between them. Most of the previous findings only evaluate the impact of mobility models and single path routing protocols with CBR traffic, whereas a significant finding of this study is that how the interaction between mobility models and single path and multipath routing protocols varies depending on the usage of traffic (TCP and CBR).     

Targeted reconstruction with differential planar computed tomography

In computed tomography, targeted (or zoomed) reconstruction is usually used to achieve high-resolution reconstruction to a small region-of-interest (ROI). This paper reports a novel targeted reconstruction method based on the recently developed differential planar computed tomography technology. With the central-slice sinogram of scanning a planar object, the primary orientation of the object is first determined for the first projection. Then by identifying the dimensions of the ROI and its offsets to the centre-of-rotation (COR), the targeted reconstruction matrix is defined, which just covers the ROI and follows its initial orientation at the scan start time. By scanning and reconstructing a small planar ROI soldered on a large planar substrate, we demonstrate the advantages of the proposed method over traditional CT, including the smaller reconstruction size and less computation time, high-resolution reconstruction and good-orientated CT image for subsequent de-layering and visualization.