L’insegnamento della matematica nelle scuole superiori mette spesso i docenti nella condizione di... more L’insegnamento della matematica nelle scuole superiori mette spesso i docenti nella condizione di percepire il pericolo che le attività e gli obblighi scolastici oscurino la vera natura di questa disciplina; essi rischiano così di essere tra i principali responsabili di quella diffusa opinione per cui la matematica è solo una materia arida, piena di calcoli complicati, un insieme di astratte e noiose regole. Ma così come la musica e la letteratura non si riducono rispettivamente al solfeggio e alle regole della grammatica e della retorica, la matematica è molto di più delle tecniche e delle regole di calcolo che si apprendono a scuola. Partendo da queste considerazioni è sorta in noi l’esigenza di ricordare agli altri insegnanti, ai mass-media ma, soprattutto, agli studenti, che la matematica è un elemento essenziale di tutta la nostra cultura, non solo di quella scientifica. É stato, quindi, approfondito il suo legame con una disciplina solitamente percepita agli antipodi, l’arte, ed è nata così una mostra che tenta di rendere meno oscuro il legame tra questi due modi di percepire la realtà. Abbiamo cercato di infrangere i luoghi comuni sulla matematica facendone riscoprire il fascino irresistibile che contagia la vita dell’uomo anche nelle arti, mostrando che essa può intervenire nei capolavori di alcuni artisti come una sorta di anima invisibile. Da questo deriva il titolo della mostra: Matematica: anima segreta dell’arte. Alla sua realizzazione hanno collaborato anche la prof.ssa Maria Cristina Castellazzi, che ha preparato i poster sulla “poesia visiva”, il prof. Aldo Meschiari, che ha predi- sposto il pannello sulle “Città invisibili” e il prof. Paolo dall’Olio che ha realizzato un’opera dal titolo “Il ragno”, che è stata donata alla scuola e fa parte della mostra. Con il contributo del Dipartimento di Matematica dell’Università di Modena e Reggio Emilia, nell’ambito del Progetto Lauree Scientifiche Orientamento e formazione degli insegnanti: MATEMATICA, abbiamo inoltre realizzato un CD-rom che riprende tutti i contenuti della mostra affinché l’iniziativa possa avere una più ampia diffusione soprattutto nelle scuole.
DAHP synthase (EC 4.1.2.15) is one of the key enzymes involved in aromatic amino acid biosynthesi... more DAHP synthase (EC 4.1.2.15) is one of the key enzymes involved in aromatic amino acid biosynthesis in Escherichia coli. An approximately twofold decrease in DAHP synthase activity level was detected in the late growth phase of the l-phenylalanine (Phe)-producing E. coli strain, in which this enzyme encoded by aroG4 is resistant to feedback inhibition. An additional copy of aroG4 that is controlled by promoters of E. coli phoA or pstS genes was integrated into the chromosome of the Phe producer. The choice of promoter was based on the detected activation of the Pho regulon that occurs in response to the depletion of soluble inorganic orthophosphate (Pi) in the medium, provided that the optical density of the Phe-producing culture did not exceed 70% of its maximum value. Pho-mediated aroG4 transcription increased both the accumulation of Phe and the level of DAHP synthase activity in the late stage of batch cultivation on glucose in Pi-limited conditions. Disruption of rpoS led to the improved performance of a PphoA -aroG4 strain. The pstS promoter that is recognized by the σ70/σS-associated core RNA polymerase resulted in the stable maintenance of DAHP synthase activity during long-drawn fed-batch cultivation of the RpoS+ strain carrying the PpstS -aroG4.
Geological models are becoming increasingly large and detailed to account for heterogeneous struc... more Geological models are becoming increasingly large and detailed to account for heterogeneous structures on different spatial scales. To obtain simulation models that are computationally tractable, it is common to remove spatial detail from the geological description by upscaling. Pressure and transport equations are different in nature and generally require different strategies for optimal upgridding. To optimize the accuracy of a transport calculation, the coarsened grid should generally be constructed based on a posteriori error estimates and adapt to the flow patterns predicted by the pressure equation. However, sharp and rigorous estimates are generally hard to obtain, and herein we therefore consider various ad hoc methods for generating flow-adapted grids. Common for all is that they start by solving a single-phase flow problem once and then continue to form a coarsened grid by amalgamating cells from an underlying fine-scale grid. We present several variations of the original method. First, we discuss how to include a priori information in the coarsening process, e.g. to adapt to special geological features or to obtain less irregular grids in regions where flow-adaption is not crucial. Second, we discuss the use of bi-directional versus net fluxes over the coarse blocks and show how the latter gives systems that better represent the causality in the flow equations, which can be exploited to develop very efficient nonlinear solvers. Finally, we demonstrate how to improve simulation accuracy by dynamically adding local resolution near strong saturation fronts.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2000
The huge amount of raw data collected during routine 14C AMS measurements requires sophisticated ... more The huge amount of raw data collected during routine 14C AMS measurements requires sophisticated processing tools to guarantee the quality and reliability of the resulting radiocarbon dates. This paper discusses the automatic evaluation system, that is in use ...
... The Effect of Compounding Techniques on the Mechanical Properties of Oil Palm Empty Fruit Bun... more ... The Effect of Compounding Techniques on the Mechanical Properties of Oil Palm Empty Fruit Bunch ... A Review of Particulate Reinforcement Theories for Polymer Composites, J. Mat. ...Fiber-reinforced Composites: Materials, Manufacturing and Design, Marcel Dekker, New York. ...
The Quality of Service (QoS) concept is of central impor- tance in the context of multimedia syst... more The Quality of Service (QoS) concept is of central impor- tance in the context of multimedia systems. Generally, multimedia systems comprise the following functional units: networks, end-to-end protocols, data management systems (DMSs), applications, human-computer inter- faces, and operating systems. Obviously, the entire system is influencing QoS that is visible to human users at the human computer interface. How- ever, the relevance of DMS aspects for QoS in multimedia systems has not been broadly recognized. In this paper, we identify QoS characteristics that are visible at the a pplication - DMS interface. Furthermore, we discuss for some QoS characteristics the cor responding mechanisms within DMSs and describe two concrete types of DMSs that aim at QoS support: realtime da- tabase systems and multimedia storage servers.
Sharka disease, caused by the plum pox virus (PPV), is one of the major limiting factors for ston... more Sharka disease, caused by the plum pox virus (PPV), is one of the major limiting factors for stone fruit crops in Europe and America. In particular, apricot is severely affected suffering significant fruit losses. Thus, PPV resistance is a trait of great interest for the apricot breeding programs currently in progress. In this work, two apricot maps, earlier constructed with the F1 ‘Goldrich × Currot’ (G×C) and the F2 ‘Lito × Lito’-98 (L×L-98) populations, have been improved including 43 and 37 new simple sequence repeat (SSR) loci, respectively, to facilitate PPV resistance trait mapping. Screening of PPV resistance on the segregating populations classified seedling phenotypes into resistant or susceptible. A non-parametric mapping method, based on the Kruskal–Wallis (KW) rank sum test, was initially used to score marker–trait association, and results were confirmed by interval mapping. Contrary to the putative digenic model inferred from the phenotypic segregations, all significant markers for the KW statistic (P < 0.005) mapped in a unique region of ~21.0 and ~20.3 cM located on the upper part of the G1 linkage group in ‘G×C’ and ‘L×L-98’ maps, respectively. According to the data, PPV resistance is suggested to be controlled by at least one major dominant locus. The association between three SSRs distributed within this region and the PPV resistance was tested in two additional populations (‘Goldrich × Canino’ and ‘Lito × Lito’-00) and breeding program parents. The marker ssrPaCITA5 showed the highest KW value (P < 0.005) in all cases, pointing out its usefulness in marker-assisted selection.
L’insegnamento della matematica nelle scuole superiori mette spesso i docenti nella condizione di... more L’insegnamento della matematica nelle scuole superiori mette spesso i docenti nella condizione di percepire il pericolo che le attività e gli obblighi scolastici oscurino la vera natura di questa disciplina; essi rischiano così di essere tra i principali responsabili di quella diffusa opinione per cui la matematica è solo una materia arida, piena di calcoli complicati, un insieme di astratte e noiose regole. Ma così come la musica e la letteratura non si riducono rispettivamente al solfeggio e alle regole della grammatica e della retorica, la matematica è molto di più delle tecniche e delle regole di calcolo che si apprendono a scuola. Partendo da queste considerazioni è sorta in noi l’esigenza di ricordare agli altri insegnanti, ai mass-media ma, soprattutto, agli studenti, che la matematica è un elemento essenziale di tutta la nostra cultura, non solo di quella scientifica. É stato, quindi, approfondito il suo legame con una disciplina solitamente percepita agli antipodi, l’arte, ed è nata così una mostra che tenta di rendere meno oscuro il legame tra questi due modi di percepire la realtà. Abbiamo cercato di infrangere i luoghi comuni sulla matematica facendone riscoprire il fascino irresistibile che contagia la vita dell’uomo anche nelle arti, mostrando che essa può intervenire nei capolavori di alcuni artisti come una sorta di anima invisibile. Da questo deriva il titolo della mostra: Matematica: anima segreta dell’arte. Alla sua realizzazione hanno collaborato anche la prof.ssa Maria Cristina Castellazzi, che ha preparato i poster sulla “poesia visiva”, il prof. Aldo Meschiari, che ha predi- sposto il pannello sulle “Città invisibili” e il prof. Paolo dall’Olio che ha realizzato un’opera dal titolo “Il ragno”, che è stata donata alla scuola e fa parte della mostra. Con il contributo del Dipartimento di Matematica dell’Università di Modena e Reggio Emilia, nell’ambito del Progetto Lauree Scientifiche Orientamento e formazione degli insegnanti: MATEMATICA, abbiamo inoltre realizzato un CD-rom che riprende tutti i contenuti della mostra affinché l’iniziativa possa avere una più ampia diffusione soprattutto nelle scuole.
DAHP synthase (EC 4.1.2.15) is one of the key enzymes involved in aromatic amino acid biosynthesi... more DAHP synthase (EC 4.1.2.15) is one of the key enzymes involved in aromatic amino acid biosynthesis in Escherichia coli. An approximately twofold decrease in DAHP synthase activity level was detected in the late growth phase of the l-phenylalanine (Phe)-producing E. coli strain, in which this enzyme encoded by aroG4 is resistant to feedback inhibition. An additional copy of aroG4 that is controlled by promoters of E. coli phoA or pstS genes was integrated into the chromosome of the Phe producer. The choice of promoter was based on the detected activation of the Pho regulon that occurs in response to the depletion of soluble inorganic orthophosphate (Pi) in the medium, provided that the optical density of the Phe-producing culture did not exceed 70% of its maximum value. Pho-mediated aroG4 transcription increased both the accumulation of Phe and the level of DAHP synthase activity in the late stage of batch cultivation on glucose in Pi-limited conditions. Disruption of rpoS led to the improved performance of a PphoA -aroG4 strain. The pstS promoter that is recognized by the σ70/σS-associated core RNA polymerase resulted in the stable maintenance of DAHP synthase activity during long-drawn fed-batch cultivation of the RpoS+ strain carrying the PpstS -aroG4.
Geological models are becoming increasingly large and detailed to account for heterogeneous struc... more Geological models are becoming increasingly large and detailed to account for heterogeneous structures on different spatial scales. To obtain simulation models that are computationally tractable, it is common to remove spatial detail from the geological description by upscaling. Pressure and transport equations are different in nature and generally require different strategies for optimal upgridding. To optimize the accuracy of a transport calculation, the coarsened grid should generally be constructed based on a posteriori error estimates and adapt to the flow patterns predicted by the pressure equation. However, sharp and rigorous estimates are generally hard to obtain, and herein we therefore consider various ad hoc methods for generating flow-adapted grids. Common for all is that they start by solving a single-phase flow problem once and then continue to form a coarsened grid by amalgamating cells from an underlying fine-scale grid. We present several variations of the original method. First, we discuss how to include a priori information in the coarsening process, e.g. to adapt to special geological features or to obtain less irregular grids in regions where flow-adaption is not crucial. Second, we discuss the use of bi-directional versus net fluxes over the coarse blocks and show how the latter gives systems that better represent the causality in the flow equations, which can be exploited to develop very efficient nonlinear solvers. Finally, we demonstrate how to improve simulation accuracy by dynamically adding local resolution near strong saturation fronts.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2000
The huge amount of raw data collected during routine 14C AMS measurements requires sophisticated ... more The huge amount of raw data collected during routine 14C AMS measurements requires sophisticated processing tools to guarantee the quality and reliability of the resulting radiocarbon dates. This paper discusses the automatic evaluation system, that is in use ...
... The Effect of Compounding Techniques on the Mechanical Properties of Oil Palm Empty Fruit Bun... more ... The Effect of Compounding Techniques on the Mechanical Properties of Oil Palm Empty Fruit Bunch ... A Review of Particulate Reinforcement Theories for Polymer Composites, J. Mat. ...Fiber-reinforced Composites: Materials, Manufacturing and Design, Marcel Dekker, New York. ...
The Quality of Service (QoS) concept is of central impor- tance in the context of multimedia syst... more The Quality of Service (QoS) concept is of central impor- tance in the context of multimedia systems. Generally, multimedia systems comprise the following functional units: networks, end-to-end protocols, data management systems (DMSs), applications, human-computer inter- faces, and operating systems. Obviously, the entire system is influencing QoS that is visible to human users at the human computer interface. How- ever, the relevance of DMS aspects for QoS in multimedia systems has not been broadly recognized. In this paper, we identify QoS characteristics that are visible at the a pplication - DMS interface. Furthermore, we discuss for some QoS characteristics the cor responding mechanisms within DMSs and describe two concrete types of DMSs that aim at QoS support: realtime da- tabase systems and multimedia storage servers.
Sharka disease, caused by the plum pox virus (PPV), is one of the major limiting factors for ston... more Sharka disease, caused by the plum pox virus (PPV), is one of the major limiting factors for stone fruit crops in Europe and America. In particular, apricot is severely affected suffering significant fruit losses. Thus, PPV resistance is a trait of great interest for the apricot breeding programs currently in progress. In this work, two apricot maps, earlier constructed with the F1 ‘Goldrich × Currot’ (G×C) and the F2 ‘Lito × Lito’-98 (L×L-98) populations, have been improved including 43 and 37 new simple sequence repeat (SSR) loci, respectively, to facilitate PPV resistance trait mapping. Screening of PPV resistance on the segregating populations classified seedling phenotypes into resistant or susceptible. A non-parametric mapping method, based on the Kruskal–Wallis (KW) rank sum test, was initially used to score marker–trait association, and results were confirmed by interval mapping. Contrary to the putative digenic model inferred from the phenotypic segregations, all significant markers for the KW statistic (P < 0.005) mapped in a unique region of ~21.0 and ~20.3 cM located on the upper part of the G1 linkage group in ‘G×C’ and ‘L×L-98’ maps, respectively. According to the data, PPV resistance is suggested to be controlled by at least one major dominant locus. The association between three SSRs distributed within this region and the PPV resistance was tested in two additional populations (‘Goldrich × Canino’ and ‘Lito × Lito’-00) and breeding program parents. The marker ssrPaCITA5 showed the highest KW value (P < 0.005) in all cases, pointing out its usefulness in marker-assisted selection.
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