First extraction of the scalar proton dynamical polarizabilities from real Compton scattering data

We present the first attempt to extract the scalar dipole dynamical polarizabilities from proton real Compton scattering data below pion-production threshold. The theoretical framework combines dispersion relations technique, low-energy expansion and multipole decomposition of the scattering amplitudes. The results are obtained with statistical tools that have never been applied so far to Compton scattering data and are crucial to overcome problems inherent to the analysis of the available data set.Comment: 8 pages, 4 figures, 2 tables; extended version to appear in Phys. Rev.

Proton scalar dipole polarizabilities from real Compton scattering data, using fixed-t subtracted dispersion relations and the bootstrap method

We perform a fit of the real Compton scattering (RCS) data below pion-production threshold to extract the electric ($\alpha_{E1}$) and magnetic ($\beta_{M1}$) static scalar dipole polarizabilities of the proton, using fixed-$t$ subtracted dispersion relations and a bootstrap-based fitting technique. The bootstrap method provides a convenient tool to include the effects of the systematic errors on the best values of $\alpha_{E1}$ and $\beta_{M1}$ and to propagate the statistical errors of the model parameters fixed by other measurements. We also implement various statistical tests to investigate the consistency of the available RCS data sets below pion-production threshold and we conclude that there are not strong motivations to exclude any data point from the global set. Our analysis yields $\alpha_{E1} = (12.03^{+0.48}_{-0.54})\times 10^{-4} \text{fm}^3$ and $\beta_{M1} = (1.77^{+0.52}_{-0.54})\times 10^{-4} \text{fm}^3$, with p-value $= 12\%$.Comment: 19 pages, 11 figures, 4 tables; final version accepted for publication in J. Phys.

Understanding organisational improvisation : foundations and performance implications

This research is grounded in strategy process theory and contingency theory and the main research aims are to investigate the antecedent factors affecting organisational improvisation and to identify how improvisation determines firm performance. This study is the first to examine the antecedent factors, which are categorised onto managerial and organisational factors that drive improvisation. The managerial factors contain the reasoning ability of managers (intuitive and rational) and managers' characteristics (selfconfidence, manager's expertise and attitude towards risk‐taking). Whilst the organisational factors include organisational structure and characteristics (goal clarity, organisational structure, organisational flexibility and organisational risk‐taking), and information processing (organisational information and organisational memory). Environmental turbulence (technology, market and competitive) is examined as an external moderating factor to the improvisation–performance relationship. Fifteen hypotheses were developed and examined in this study. A cross sectional survey methodology was used to test the hypotheses of this study. A postal questionnaire primary data was collected from 128 top management executives of high technology‐based companies in Malaysia. In summary, the findings confirm that a total accumulated variance in organisational improvisation was collectively explained by managerial factors and organisational factors; thus confirming that those aforementioned factors have statistically significant associations with organisational improvisation. Based on the study of the improvisation–performance relationship, the results revealed a positive significant relationship between both factors. Surprisingly, once the environmental turbulence factors were introduced as a moderator, the result on the association between improvisation and firm performance was greater than before; thus demonstrating a significant moderating effect on the relationships between organisational improvisation and firm performance. However, mixed results were identified when the association between each antecedent and improvisation was tested and the effect of each moderating factor was individually examined. This study on the effect of internal and external factors on organisational improvisation and firm performance makes novel contributions to the existing body of knowledge as well as to practitioners. It is noticeable that organisational improvisation in strategic management is crucial as a decision‐making mechanism for improving organisational performance. Hence, managers themselves as well as other relevant factors within firm hierarchy should facilitate and induce necessary condition that may drive organisational improvisation to happen.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Biodiversity loss in a small riverine wetland of the Ticino river (Lombardia, Northern Italy)

Wetlands are heterogeneous habitats that include various biotopes with different formations, structures and geographical positions. There are many small wetlands in the Ticino river area around Pavia (Lombardia, Northern Italy), many of which evolve naturally and originate from abandoned riverbeds, isolated river meanders, oxbow lakes or small ponds fed by terrace springs or underground waters. We decided to consider the evolution of one of these wetlands, namely the Topo oxbow lake. It had previously been studied 24 years ago (1988-1990), so we compared the results with those collected during a recent one-year investigation (June 2011-June 2012) on the following aspects: dimensions, hydrometric level fluctuation and bathymetry, principal chemical-physical parameters, hygrophytic and aquatic vegetation, and zooplankton communities. The resulting geo-morphological and biotic community changes are typical of riverine wetlands, thus supporting the hypothesis that this oxbow lake is following its natural evolution. Morphological changes in the oxbow lake should influence its biotic communities: the high plant biomass that existed in the past could be considered to have been the first step towards eutrophication, but the oxbow lake remained at mesotrophic level due to high biodiversity and dissolved oxygen levels in the water. Nowadays, the lower biodiversity in aquatic plants and zooplankton suggests a trophic level shift towards eutrophication due to the endogenous evolution of the oxbow lake. However, these ideas are not supported by the physical and chemical parameters of the water which indicate that the oxbow lake is still at mesotrophic level. We would suggest planning a gentle restoration of this biotope, with the aim of rejuvenating the physical habitat to ensure the long-term ecological functioning of the aquatic environment

First record of eyeless specimens of Gammarus roeselii Gervais 1835 (Amphioda, Gammaridae) in a small stream of the sub-lacustrine Ticino River basin (Lombardy, Northern Italy)

In this short communication, we report the unusual presence of blind specimens of the non-native Gammarus roeselii Gervais 1835 (Amphioda, Gammaridae) in the sub-lacustrine Ticino River basin (Po River floodplain, Northern Italy). Considering that G. roeselii is present in almost all small semi-natural tributaries of the Ticino River, it is important to carry out further research on this well-established exotic species to verify its genetic variability

Statistical approach for the first extraction of dipole dynamical polarizabilities from proton real Compton scattering data

In this work we describe a statistical technique that has been recently applied for the extraction of the proton scalar dipole dynamical polarizabilities from real Compton scattering data. The technique is based on the simplex minimization and on the parametric bootstrap and has several important advantages with respect to the standard χ2 minimization technique, as, for example, the possibility to include in a straightforward way the systematic error in the minimization procedure

Terrace springs: habitat haven for macrobenthic fauna in the lower plain of the River Ticino (Lombardy, Northern Italy)

Springs are important environments between hypogean and epigean habitats; the interaction between aquatic and terrestrial ecosystems is an important factor for their biotic communities. We investigated the ecology of the macrobenthic community of two lowland springs in the River Ticino valley, focusing on the autoecology of some relevant species and on the role of springs as hotspots of biodiversity in an area threatened by anthropogenic pressure. We collected 26 taxa in total: diptera (8), trichoptera (6), gastropods (5), coleoptera (2), crustacea (2), lumbricidae (1), odonata (1), plathelminthes (1). Some of them are stenothermal and oligotrophic species thus quite unusual for a flood plain area characterized by intensive agricultural activities. In conclusion, our study highlights the importance of lowland springs in conserving some habitat-selective macrobenthic species

Role of the artificial structures on biodiversity: the case of arthropod fauna in the North Adriatic lagoons

SUMMARY -Role of the artificial structures on biodiversity: the case of arthropod fauna in the North Adriatic lagoons - The lagoons of the North Adriatic region are site of several anthropic activities, which express themselves also with the abundance of artificial structures like the wooden poles (bricole). These become suitable substrate for the colonization of numerous species that, in their absence, would not find an opportune substrate in the natural soft bottoms of the lagoon. Using the arthropod taxocoenosis as study-case, in this work we provide evidence that the presence of artificial hard substrates has a double effect on the biodiversity of this taxon, as they promote the settlement of (i) a much larger pool of species than the one of the surrounding soft bottoms and (ii) of species which are new for the Adriatic transitional environments. In particular, an amphipod already known in the Mediterranean but new for the Adriatic, Ampithoe ferox (Chevreux), has been recorded on the artificial hard substrates of the Sacca di Goro (Po delta). In order to facilitate the identification of this scarcely known species, we provide a key to distinguish it from the more common congener Ampithoe ramondi Audouin. RIASSUNTO -Il ruolo delle strutture artificiali sulla biodiversità degli artropodi lagunari nord adriatici -Le lagune della regione nord-adriatica sono sede di numerose attività antropiche; per questo è frequente trovarvi diverse strutture artificiali tra cui le bricole di legno. Queste costituiscono un substrato idoneo alla colonizzazione di numerose specie che non troverebbero un habitat opportuno nei fondali naturali delle lagune. Considerando la taxocenosi degli artropodi come modello di studio, in questo lavoro si prova che la presenza di substrati duri artificiali ha un duplice effetto sulla biodiversità di questo taxon, poiché favorisce l'insediamento (i) di un pool di specie ben più consistente rispetto a quello degli adiacenti fondi molli e (ii) di specie nuove per gli ambienti di transizione adriatici. In particolare, per i fondi duri artificiali della Sacca di Goro (delta del Po) viene segnalata la presenza dell'anfipode Ampithoe ferox (Chevreux), già noto per il Mediterraneo ma nuovo per l'Adriatico. Al fine di facilitare l'identificazione di questa specie poco conosciuta, viene fornita una chiave per distinguerla dalla ben più diffusa congenerica Ampithoe ramondi Audouin

the increasing distribution of gammarus roeselii gervais 1835 first record of the non indigenous freshwater amphipod in the sub lacustrine ticino river basin lombardy italy

This paper reports the first record of the non-indigenous species Gammarus roeselii Gervais, 1835 in the sub-lacustrine Ticino River basin (Po river floodplain, Northern Italy). Up to now in Italy, this Balkanian amphipod, known as an "exotic species, well established" in Central Europe, had only been reported in the North-Eastern part of the country (Sile River basin). Gammarus roeselii has a low spreading potential, so its presence in other parts of Europe can only be explained by human activities. However, the available data suggests that its presence in the sub-lacustrine Ticino River basin does not currently represent a threat to the population of the native Echinogammarus stammeri, which is still very healthy in this area

OXA-244-Producing ST131 Escherichia coli From Surface and Groundwaters of Pavia Urban Area (Po Plain, Northern Italy)

The study aimed to investigate (i) the occurrence of third-generation cephalosporins and/or carbapenems non-sensitive Enterobacterales in Pavia surface and groundwaters, (ii) their resistance determinants, and (iii) the clonal features of the most relevant strains. During May 13 and 14, 2019, n = 18 water samples from n = 12 sampling sites in the urban/peri-urban area of Pavia (Po Plain, Northern Italy) have been evaluated. At first, hydrochemical analysis and bacterial plate counts were carried out on all the water samples. One milliliter of each water sample was then screened on both MacConkey agar (MC) added with cefotaxime (1 mg/L; 2 mg/L) and MC plus meropenem (0.25 mg/L; 4 mg/L). Species identification and antimicrobial susceptibilities were assessed by MicroScan autoSCAN-4. Double Disk Synergy (DD) test, CT103XL microarray, acc(6')-Ib-cr, qnrS, blaCTX-M-/MOX-/VEB-/OXA-type genes targeted PCR and sequencing, Pulsed-Field Gel Electrophoresis (PFGE), MultiLocus Sequence Typing (MLST), and Whole-Genome Sequencing on selected strains were performed. A total of n = 30 isolates grown on β-lactams enriched MC: Escherichia coli (n = 21; 70%), Klebsiella spp. (n = 5; 16.6%), Citrobacter freundii (n = 2; 6.7%), and Kluyvera intermedia (n = 2; 6.7%). All E. coli and K. pneumoniae were ESβL-producers by DD. The 66.6, 38.0, and 19.0% of E. coli were ciprofloxacin/levofloxacin, trimethoprim-sulfamethoxazole, and gentamicin resistant (EUCAST 2019 breakpoints), respectively. A blaCTX-M-type determinant was identified in E. coli (n = 20/21; 95.2%) and K. pneumoniae (n = 2/3; 66.7%). The remaining E. coli was blaVEB-1 and blaMOX-2 genes positive. The aac(6')-Ib-cr determinant was found in n = 7 E. coli and n = 1 K. pneumoniae, while qnrS was found in n = 1 E. coli and n = 2 K. pneumoniae. PFGE showed clonal heterogeneity among ESβL-E. coli. Two out of four E. coli detected as blaOXA-244-positive, belonged to the pandemic ST131. One XDR K. pneumoniae from a stream sample, detected as blaKPC-2 positive, resulted of ST258. The epidemiological impact of blaOXA-244 ST131 E. coli and blaKPC-2 ST258 K. pneumoniae presence in surface waters of an urban area in Northern Italy must not be underestimated