1,183 research outputs found
The distribution of cirripeds and gastropods on plain vertical rock surfaces in the upper intertidal and splash zones
This is a student paper done for a University of California Berkeley Zoology class. Since UCB didn't have its own marine lab at the time, it rented space at Hopkins Marine Station where this work was done. Cadet Hand earned his Ph.D. from Berkeley and went on to become Director of the Bodega Marine Laboratory. Donald Putnam Abbott also earned his Ph.D. from Berkeley and later became a Stanford professor at Hopkins Marine Station. (PDF contains 26 pages
The answers are within me. An evaluation of a person centred counselling service for men at HMP Doncaster who have had experience of domestic violence 2005-2007
This report is the second year evaluation of the person centred counselling service for male victims and perpetrators of domestic violence at HMP Doncaster in 2006/7. This report follows on from the previous year's evaluation, Raging Anger Within Me, which evaluated this project in 2005/6. Initiated by the Doncaster Rape and Sexual Abuse Counselling Centre (DRSACC), the second year of counselling service delivery was also funded by Lloyds TSB and the Tudor Trust.
The report provides a background to the service offered, details the key factors in the service's success and makes recommendations for the future sustainability of this innovative service. The report also contains a particularly interesting section detailing how the appropriateness of the service is perceived by experienced prison staff
Palaeoceanographic implications of new and revised bio-chronostratigraphic constraints from the Profitis Ilias Unit (Rhodes, Greece)
Middle Oxfordian-early Kimmeridgian radiolaria, extracted from the top of radiolarites of Profitis Ilias unit (Rhodes island), suggest that the latter are essentially Middle Jurassic in age and the overlying siliceous shales Late Jurassic. The previously identified Calpionellid horizon at the top of Profitis Ilias siliceous marls is now regarded as early Valanginian in age. The above chronostratigraphic constraints allow tentative correlations to be made between Profitis Ilias and Pindos-Olonos sedimentary units. Finally, the palaeoceanographic significance of the studied series in Rhodes and potentially similar pelagic sequences in the Marmaris area of Turkey are discussed
Rayleigh-wave dispersion curve: a proxy for site effect estimation?
One of the open issues on the effects of surface geology regards the estimation of site response when limited resources are available.
In that restrictive context, one solution is to use soil characteristics as proxy. Despite its extensive use, the most common proxy, Vs30, is presently criticized because it cannot carry alone the main physics of site response. We propose here a statistical investigation of the capabilities of another proxy, the Rayleigh-wave dispersion curve, DC. When considered over a broad enough frequency band, it can provide deeper information missing in the single Vs30 parameter.
A set of shear-wave velocity profiles measured for more than 600 Japanese KiK-net stations is used to compute theoretical dispersion curves (DC) and theoretical SH transfer functions (SH), while instrumental surface/downhole spectral ratios were calculated in a previous work (Cadet et al., 2011a). Canonical correlation techniques are applied to this large data set to analyze the relationship between DC and theoretical or empirical site responses. The results indicate very encouraging qualitative statistical relationships between DC and site amplification for numerically derived SH transfer functions, showing significant canonical couples with correlations up to 0.95. Results for instrumental surface/downhole transfer functions correspond to lower correlations (up to 0.73) but still allow the development of quantitative relationships
Novel thermostable Y-family polymerases: applications for the PCR amplification of damaged or ancient DNAs
For many years, Taq polymerase has served as the stalwart enzyme in the PCR amplification of DNA. However, a major limitation of Taq is its inability to amplify damaged DNA, thereby restricting its usefulness in forensic applications. In contrast, Y-family DNA polymerases, such as Dpo4 from Sulfolobus solfataricus, can traverse a wide variety of DNA lesions. Here, we report the identification and characterization of five novel thermostable Dpo4-like enzymes from Acidianus infernus, Sulfolobus shibatae, Sulfolobus tengchongensis, Stygiolobus azoricus and Sulfurisphaera ohwakuensis, as well as two recombinant chimeras that have enhanced enzymatic properties compared with the naturally occurring polymerases. The Dpo4-like polymerases are moderately processive, can substitute for Taq in PCR and can bypass DNA lesions that normally block Taq. Such properties make the Dpo4-like enzymes ideally suited for the PCR amplification of damaged DNA samples. Indeed, by using a blend of Taq and Dpo4-like enzymes, we obtained a PCR amplicon from ultraviolet-irradiated DNA that was largely unamplifyable with Taq alone. The inclusion of thermostable Dpo4-like polymerases in PCRs, therefore, augments the recovery and analysis of lesion-containing DNA samples, such as those commonly found in forensic or ancient DNA molecular applications
Statistical investigation of site ef f ects with emphasis on sedimentary basins, using earthquake and ambient noise recordings
During the last two decades, three empirical methods for assessing site effects have been
widely used: the Standard Spectral Ratio (SSR), the Horizontal-to-Vertical Spectral Ratio from earthquake recordings (HVSR) and the Horizontal-to-Vertical Spectral Ratio from ambient noise recordings (HVN). The SSR is considered the reference empirical method
to detect amplification as a function of frequency, while the HVSR and the HVN
realistically indicate fundamental frequency but, for the majority of the worldwide
examined sites, they cannot give reliable amplification curves as a function of
frequency. Given the fact that HVSR and especially HVN can be easily obtained, it is
challenging to search for any correlation with SSR amplification functions.
We used recordings from 168 sites worldwide, for which all three types of spectral ratios
were homogeneously processed (Haghsenas et al., Bull. Earthquake Eng. 2008). On this
data set we applied standard multivariate statistical analyses, namely, factor analysis and canonical correlation, to investigate and quantify -where it is possible- any correlation between spectral ratios for a certain number of the examined frequency bins. Results show that the correlation between HVN and HVSR is very good. Moreover, their correlation with broad band SSR can be statistically quantified and receive a satisfactory physical explanation.
In addition, we looked for the correlation of SSR, HVSR and HVN collected in sedimentary basins (a subset of the previous database) with geometrical and geophysical
parameters. T hese attempts were constrained by the limited amount of reliable in-situ
data. Among many, we select 5 parameters: Vs30, Hb, Vs_average/Hb, Hb/W_valley,
Hb/W_edge (where Hb is the bedrock’s depth below the station; Vs_average is the
average Vs from surface to bedrock; W_valley is 2D-width of the valley; W_edge is the
distance from the closest valley’s edge). T he analysis assesses that larger are the first 4 parameters, larger is the low-frequency amplification in HVSR and HVN, and lower the high-frequency contribution.
Although additional data would improve our statistical investigation and better establish quantitative correlation between spectral ratios and geophysical or/and geometrical characteristics of sedimentary basins, our results clearly show that statistical correlation between SSR and HVN-HVSR is present and modulated in specific frequency domains.
T his study has been performed in the framework of the T oK IT SAK-GR EC project
(2006-2010)
Analisi statistica degli effetti di sito da dati di terremoti e di rumore ambientale.
L’ultimo ventennio ha visto lo sviluppo e l’uso di tre metodi empirici per l’analisi degli effetti di sito: Standard Spectral Ratio (SSR), Horizontal-to-Vertical Spectral Ratio da registrazioni sismiche (HVSR) e Horizontal-to-Vertical Spectral Ratio da registrazioni di rumore ambientale (HVN). SSR è considerato il metodo empirico di riferimento per rilevare le amplificazioni in funzione della frequenza. HVSR e HVN, invece, danno una stima realistica della frequenza fondamentale ma, generalmente, non riescono a fornire valori affidabili di amplificazione.
Nel presente lavoro sono state utilizzate le registrazioni sismiche effettuate in 168 siti provenienti da diverse aree geografiche e per cui sono stati calcolati tutti e tre i tipi di rapporti spettrali (Haghsenas et al., 2008). Su questi dati abbiamo applicato delle analisi statistiche multivariate quali la correlazione canonica (Davis, 2002), con lo scopo di mettere in evidenza e quantificare le correlazioni tra i differenti rapporti spettrali nell’intero intervallo di frequenza compreso tra 0.2Hz e 10Hz. Questo tipo di analisi permette inoltre di associare alle correlazioni una stima della loro significatività ed è stata già utilizzata da Theodulidis et al. (2008) per studiare la relazione tra HVN e danneggiamento in aree urbane.
I risultati mostrano che la correlazione tra HVN e HVSR è molto buona ad esclusione delle basse frequenze e che, per entrambe le tecniche, la presenza di un picco di amplificazione nell’intervallo 0.6-2 Hz è correlato ad un minimo per frequenze 3-10Hz. I picchi di amplificazione evidenziati da queste due tecniche sono inoltre correlabili con un più largo intervallo di frequenze nei rapporti SSR.
Abbiamo quindi esteso l’analisi per correlare SSR, HVSR e HVN in bacini sedimentari (un subset dei dati utilizzati) con parametri geofisici e geometrici. La riduzione del numero dei dati deriva dall’esigenza di avere siti con una buona qualità di informazioni geofisiche e geometriche. Sono stati scelti cinque parametri indicatori delle velocità medie delle onde S e delle caratteristiche geometriche 2D della valle.
Sebbene un più esteso data-set migliorerebbe l’analisi statistica, stabilendo migliori stime quantitative della correlazione tra rapporti spettrali e le caratteristiche geofisiche e geometriche dei bacini sedimentari, i nostri risultati mostrano chiaramente che le correlazioni tra SSR e HVN-HVSR esistono e si modulano in specifici intervalli di frequenza.
Questo studio è stato condotto nell’ambito del progetto ToK ITSAK-GR EC (2006-2010)
Statistical estimation of earthquake site response from noise recordings
Standard spectral ratio from earthquake recordings (SSR) is considered the reference empirical method for assessing site effects as a function of frequency. However, other estimates can be easily obtained from noise measurements (i.e., Horizontal-to-Vertical Spectral Ratio, HVN), even though their reliability in terms of amplitude is controversial.
In the framework of the ToK ITSAK-GR (2006-2010) EC project, Cultrera et al. (2010) analyzed recordings from 64 sites worldwide, founding that it is possible to have linear combinations of the HVN amplitudes significantly correlated to linear combinations of the SSR. In the present paper we show how to estimate the SSR spectral ratios when only noise measurements are available, using the results of the canonical correlation analysis between SSR and HVN recorded at several sites. The SSR evaluation has been tested by a cross validation procedure: the expected SSR at each validation site are in turn estimated by a weighted average of the SSR values measured at the other sites; the weights are properly set to account more for the sites with similar behavior in terms of the canonical correlation between HVN and SSR. To evaluate the goodness of the estimation, we compared all the inferred and original SSR, and we performed a critical analysis on the spectral characteristics of earthquake site response that can be easily recovered from noise measurements
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