A multidisciplinary approach to evaluate the effectiveness of natural attenuation at a contaminated site

This study evaluates the natural attenuation of chlorinated hydrocarbons as remediation action in a contaminated site downtown the city of Parma (Italy). To achieve this goal, a combination of new investigation methods (bio-molecular analysis, compound specific isotope analysis, phytoscreening) has been proposed. The approach (named circular multi step) allows to: fully understand the phenomena that occur at the study site, design new investigation activities, and manage best practices. Consequently, each step of the approach improves the conceptual and numerical models with new knowledge. The activities carried out at the study site allowed to detect a contamination of perchloroethylene in a large part of the city of Parma and, of main importance, underneath a kindergarten. The results of the study did not show significant natural attenuation of chlorinated hydrocarbons and that the detected contamination could refer to the same unknown contaminant source. Furthermore, the innovative phytoscreening technique was applied to assess the presence of chlorinated hydrocarbons at the ground level. The plume spread was estimated through numerical modeling starting from potential contaminant sources. This study enhances the knowledge of groundwater flow and contamination in Parma and allows authorities to design new investigation/reclamation activities through management actions

One-minute integrated rainfall rate statistics from a rain gauge network in Colombia: Accuracy of prediction methods

Reliable rainfall rate complementary cumulative distributions are critical for the design of microwave communications systems operating above around 8 GHz. This Letter presents the results of the analysis of more than 5 years of 1-minute integrated rainfall accumulation data for 12 stations. This new dataset will prove useful considering the sharing analyses that must be executed for IMT services in the 24.25-27.5, 37-43.5, 45.5-47, 47.2-48.2 and 66-71 GHz spectrum bands. The resulting statistics can complement the entries in the database of ITU-R Study Group 3 for the region

Pemanfaatan Ekstrak Tanaman Tembakau (Nicotianae Tobacuml ) Sebagai Pestisida Organik Untuk Pengendalian Hama Keong Mas (Pomaceace Canaliculata L.) Di Kawasan Persawahan Gampong Tungkop, Aceh Besar

Penelitian ini bertujuan untuk mengetahui pengaruh pestisida organik dari ekstrak tanaman tembakau dalam mengendalikan hama keong mas pada tanaman padi di persawahan Gampong Tungkop, Kabupaten Aceh Besar. Pendekatan dari penelitian ini adalah pendekatan kuantitatif dan kualitatif, metode yang digunakan untuk Perubahan perilaku adalah pendekatan deskriptif dan metode eksperimen pola Rancangan Acak Lengkap untuk efektivitas ekstrak tanaman tembakau dalam membasmi hama keong mas. Rancangan Acak Lengkap yang digunakan terdiri dari 5 perlakuan dan 4 kali ulangan untuk ektrak daun tembakau. Parameter yang diamati dalam penelitian ini adalah Perubahan pola perilaku keong mas dan jumlah individu yang mati. Data dianalisis dengan ANAVA pada taraf signifikasi 0,05, dilanjutkan uji lanjut Jarak Nyata Duncan. Hasil uji ANAVA menunjukkan bahwa Fhitung > Ftabel pada taraf signifikan 0,05%. Pada 3 jam Pengamatan Fhitung 3,450 > Ftabel 2,895, pada 6 jam pengamatanFhitung 4,500 > Ftabel 2,895, pada 9 jam pengamatn Fhitung 4,269 > Ftabel 2,895, dan pada 12 jam pengamatan Fhitung 3,789 > Ftabel 2,895. Jumlah kematian keong mas (P.canacilulata) yang sangat tinggi terdapat pada perlakuan P4 (20% ekstrak). Kesimpulannya adalah terdapat pengaruh pestisida organik dari ekstrak tanaman tembakau dalam kematian hama keong mas pada tanaman padi di kawasan persawahan Gampong Tungkop, Aceh Besar

Self-consistent model for ambipolar tunneling in quantum-well systems

We present a self-consistent approach to describe ambipolar tunneling in asymmetrical double quantum wells under steady-state excitation and extend the results to the case of tunneling from a near-surface quantum well to surface states. The results of the model compare very well with the behavior observed in photoluminescence experiments in $InGaAs/InP$ asymmetric double quantum wells and in near-surface $AlGaAs/GaAs$ single quantum wells.Comment: 10 pages, REVTeX 3.

Germano Sartelli

Libro-catalogo della mostra sugli artisti imolesi che hanno partecipato alle Biennali Internazionali d'arte di Venezia. Capitolo dedicato all'opera dello scultore Germano Sartelli, tra i principali esponenti dell'informale italiano

Opportunities for Technology and Tool Development: Understanding the Brain as a Whole

Major resources are now available to develop tools and technologies aimed at dissecting the circuitry and computations underlying behavior, unraveling the underpinnings of brain disorders, and understanding the neural substrates of cognition. Scientists from around the world shared their views around new tools and technologies to drive advances in neuroscience

Optimal Concentration of Light in Turbid Materials

In turbid materials it is impossible to concentrate light into a focus with conventional optics. Recently it has been shown that the intensity on a dyed probe inside a turbid material can be enhanced by spatially shaping the wave front of light before it enters a turbid medium. Here we show that this enhancement is due to concentration of light energy to a spot much smaller than a wavelength. We focus light on a dyed probe sphere that is hidden under an opaque layer. The light is optimally concentrated to a focus which does not exceed the smallest focal area physically possible by more than 68%. A comparison between the intensity enhancements of both the emission and excitation light supports the conclusion of optimal light concentration.Comment: We corrected an ambiguous description of the focus size in our abstract and text pointed out by an anonymous refere

Role and regulation of ACC deaminase gene in Sinorhizobium meliloti: Is it a symbiotic, rhizospheric or endophytic gene?

Plant-associated bacteria exhibit a number of different strategies and specific genes allow bacteria to communicate and metabolically interact with plant tissues. Among the genes found in the genomes of plant-associated bacteria, the gene encoding the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase (acdS) is one of the most diffused. This gene is supposed to be involved in the cleaving of plant-produced ACC, the precursor of the plant stress-hormone ethylene toning down the plant response to infection. However, few reports are present on the actual role in rhizobia, one of the most investigated groups of plant-associated bacteria. In particular, still unclear is the origin and the role of acdS in symbiotic competitiveness and on the selective benefit it may confer to plant symbiotic rhizobia. Here we present a phylogenetic and functional analysis of acdS orthologs in the rhizobium model-species Sinorhizobium meliloti. Results showed that acdS orthologs present in S. meliloti pangenome have polyphyletic origin and likely spread through horizontal gene transfer, mediated by mobile genetic elements. When acdS ortholog from AK83 strain was cloned and assayed in S. meliloti 1021 (lacking acdS), no modulation of plant ethylene levels was detected, as well as no increase in fitness for nodule occupancy was found in the acdS-derivative strain compared to the parental one. Surprisingly, AcdS was shown to confer the ability to utilize formamide and some dipeptides as sole nitrogen source. Finally, acdS was shown to be negatively regulated by a putative leucine-responsive regulator (LrpL) located upstream to acdS sequence (acdR). acdS expression was induced by root exudates of both legumes and non-leguminous plants. We conclude that acdS in S. meliloti is not directly related to symbiotic interaction, but it could likely be involved in the rhizospheric colonization or in the endophytic behavior

The future of universal access? merging computing, design and engineering

Technology is advancing at a fast pace while the shape and nature of computers continues to evolve, with tablets and smartphones illustrating the move away from the traditional notion of a laptop or desktop computer. Similarly, networking and sensing technologies are also developing rapidly and innovatively. All of these technologies have the potential to enfranchise users with severe functional impairments to be better able to control and interact with other people and their surroundings. However, this is only possible if those designing the novel systems based upon these new technologies consider such users’ needs explicitly. This paper examines how these technological advances can be employed to support these users in the near future. The paper further discusses issues such as the need for security as systems evolve from control of specific environments to a potential model for interaction in any location