Effects of Shallow-Velocity Reductions on 3D Propagation of Seismic Waves

We perform 3D simulations of seismic wavefields to clarify effects of strong reductions of shallow velocities on long-period seismic waves. The simulations use a reference Community Velocity Model of southern California and a modified version with strong velocity reductions in the top 500 m of the Los Angeles basin. Differences between wavefields generated by 10 earthquakes in the reference and perturbed models are analyzed. Velocity changes are estimated by measuring relative time shifts between reference and perturbed seismograms using wavelet cross-correlation spectra. The results indicate that strong localized temporal velocity drops near the surface, such as those observed during strong ground motions, may generate regional perturbations of wavefields at periods up to 20 s. These perturbations may be misinterpreted as generated by temporal changes at seismogenic depths. The results also have important implications for waveform tomography studies.

KAJIAN SEMIOTIKA PADA KARTUN BERTEMAKAN TOLAK REKLAMASI TELUK BENOA KARYA PUTU DIAN UJIANA

Bali became one of the world's best tourism destinations. Environment and culture are still awake to make a small island nicknamed the island of this god is in great demand by the tourists. This excellence is a source of energy in driving the wheels of the economy in Bali. However, this has to sacrifice some environmental sustainability to support infrastructure in the tourism sector. Such as the conversion of land into villas, hotels and others, even today which is still a hot issue in Bali is a plan to reclaim Teluk Benoa area. This unease that makes the Balinese people began to realize the side effects of tourism progress. Balinese people are known as individuals who love the environment because they are familiar with the concept of palemahaan (good relationship with the environment). This concept is a reference community to reject the project, one of which is Dian. Dian is a cartoonist who is known to be active in the campaign against the reclamation in Teluk Benoa. His cartoon works, drafted forms that could signal a message to awaken some Balinese still expecting a reclamation project. Dian's cartoons designed as a rejection of the full reclamation of semiotics, signs and meanings. Through his cartoons, Dian not only wants to entertain through his funny display of cards, but also wants to invite and realize the Balinese people, that reclamation will not only bring financial benefits, but the dangers of environmental damage will come at any time as a side effect of the reclamation plan Tanjung Benoa.

Genetic Predisposition for Dermal Problems in Hexavalent Chromium Exposed Population

We studied the effect of genetic susceptibility on hexavalent chromium induced dermal adversities. The health status of population was examined from the areas of Kanpur (India) having the elevated hexavalent chromium levels in groundwater. Blood samples were collected for DNA isolation to conduct polymorphic determination of genes, namely:NQO1(C609T),hOGG1(C1245G),GSTT1,andGSTM1(deletion). Symptomatic exposed subjects(n=38)were compared with asymptomatic exposed subjects(n=108)along with asymptomatic controls(n=148)from a non contaminated reference community. Exposed symptomatic group consisted of 36.8% subjects who wereGSTM1null genotyped as compared to asymptomatic where only 19.4% subjects were null. The exposed subjects withGSTM1null genotype were more susceptible to dermal adversities in comparison with wild genotyped subjects (OR = 2.42; 95% CI = 1.071–5.451). Age, smoking, gender or duration of residence were not found to have any confounding effect towards this association. Association with other genes was not statistically significant, nonetheless, possible contribution by these genes cannot be ruled out. In conclusion, variation in the polymorphic status ofGSTM1gene may influence dermal outcomes among residents from Cr(VI) contaminated areas. Further studies are therefore, needed to examine these observations among different population groups.

A diatom-based index for the biological assessment of eastern Canadian rivers: an application of correspondence analysis (CA)

We developed a diatom-based index that integrates the effects of multiple stresses on streams and provides information related to the "distance" from the nonimpacted state. The Eastern Canadian Diatom Index (IDEC) was based on a correspondence analysis (CA) to develop a chemistry-free index where the position of the sites along the gradient of maximum variance (first axis) is strictly determined by diatom community structure and is therefore independent of measured environmental variables. The index value indicates the distance of each diatom community from its specific reference community. A high index value represents a non- or less-impacted site, while a low index value represents a more heavily impacted site. Two sub-indices were developed based on two sets of reference communities. The IDEC-circumneutral includes the sites that have reference communities characteristic of slightly acidic or neutral environments. The IDEC-alkaline includes the sites that have reference communities characteristic of environments where pH values are naturally higher than 7.5. The distinction between the two sub-indices is fundamental to make sure that each stream has the potential to reach a high IDEC value following complete restoration of its ecosystem.