928 research outputs found

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

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    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

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

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    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

    Lean towards learning: connecting Lean Thinking and human resource management in UK higher education

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    From its origins in the automotive industry, Lean Thinking is increasingly being seen as a solution to problems of efficiency and quality in other industries and sectors. In recent years attempts have been made to transfer Lean principles and practice to the higher education sector with indications of mixed consequences and debate over its suitability. This paper contributes to the debate by drawing evidence from thirty-four interviews conducted across two UK universities that have implemented Lean in some of their activities and we pay particular attention to the role of the HR function in facilitating its introduction. The findings suggest there are problems in understanding, communicating and transferring Lean Thinking in the higher education context; that, despite HR systems being vital facets of Lean, HR professionals are excluded from participation; and that as a consequence the depth and breadth of Lean application in the two institutions is very limited

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

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    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/InPInGaAs/InP asymmetric double quantum wells and in near-surface AlGaAs/GaAsAlGaAs/GaAs single quantum wells.Comment: 10 pages, REVTeX 3.

    Evaluation of cadmium bioaccumulation-related physiological effects in salvinia biloba:An insight towards its use as pollutant bioindicator in water reservoirs

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    Free-living macrophytes play an important role in the health of aquatic ecosystems. Therefore, the use of aquatic plants as metal biomonitors may be a suitable tool for the management of freshwater reservoirs. Hence, in this study, we assessed the effects of cadmium (Cd) in Salvinia biloba specimens collected from the Middle Paraná River during a 10-day experiment employing artificially contaminated water (100 μM Cd). S. biloba demonstrated a great ability for Cd bioaccumulation in both the root-like modified fronds (named “roots”) and the aerial leaf-like fronds (named “leaves”) of the plants. Additionally, Cd toxicity was determined by the quantification of photosynthetic pigments (chlorophylls a and b, and carotenoids), flavonoids, and soluble carbohydrate contents in S. biloba over time (1, 3, 5, 7, and 10 days). In general, deterioration was more pronounced in leaves than in roots, suggesting a greater implication of the former in long-term Cd sequestration in S. biloba. Deleterious effects in the appraised parameters were well correlated with the total amount of Cd accumulated in the leaves, and with the qualitative changes observed in the plants’ phenotype during the 10-day metal exposure assay. The flavonoids and carotenoids in leaves were highly affected by low Cd levels followed by root carbohydrates. In contrast, chlorophylls and root flavonoids were the least impacted physiological parameters. Therefore, our results demonstrate that S. biloba displays dissimilar organ-linked physiological responses to counteract Cd phytotoxicity and that these responses are also time-dependent. Though further research is needed, our work suggests that easy-handled physiological data obtained from autochthonous free-floating S. biloba specimens may be used as a valuable tool for metal-polluted water biomonitoring

    Acetylation of the HIV-1 Tat protein by p300 is important for its transcriptional activity.

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    AbstractThe human immunodeficiency virus 1 (HIV-1) Tat protein activates transcriptional elongation by recruiting the positive transcription elongation factor (pTEFb) complex to the TAR RNA element, which is located at the 5′ extremity of all viral transcripts [1–3]. Tat also associates in vitro and in vivo with the transcriptional coactivator p300/CBP [4–6]. This association has been proposed to recruit the histone acetyltransferase (HAT) activity of p300 to the integrated HIV-1 promoter. We have observed that the purified p300 HAT domain acetylates recombinant Tat proteins in vitro and that Tat is acetylated in vivo. The major targets of acetylation by p300 are lysine residues (Lys50 and Lys51) in the arginine-rich motif (ARM) used by Tat to bind RNA and for nuclear import. Mutation of these residues in full-length recombinant Tat blocked its acetylation in vitro. Furthermore, mutation of these lysine residues to arginine markedly decreased the synergistic activation of he HIV promoter by Tat and p300 or by Tat and cyclin T1. These results demonstrate that acetylation of Tat by p300/CBP is important for its transcriptional activation of the HIV promoter

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

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    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

    Germano Sartelli

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    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

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

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    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
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