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Plant Growth Promoting Rhizobacteria characterization. Dissecting the role of Beijerinckia fluminensis in reducing salt stress in A. thaliana
No full textBeneficial interactions between plants and certain bacterial species have long been recognized as capable of resulting in growth enhancement and exerting protective action on economically important crops. In this study, six different bacterial strains (Paenarthrobacter ureafaciens, Beijerinckia fluminensis, Pseudomonas protegens, Arthrobacter sp., Arthrobacter defluii and Arthrobacter nicotinovorans) were characterized in terms of growth promotion in the model plant A. thaliana and antimicrobial activity against three phytopathogenic fungi in vitro (Aspergillus flavus, Fusarium proliferatum and Fusarium verticillioides). The tested strains were positive for some plant growth-promoting traits (PGPs), such as indol-3-acetic acid (IAA), 1-amino cyclopropane-1-carboxylate deaminase (ACC-deaminase), siderophore production, and phosphate solubilization. Analysis of bacterial broths by ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS) and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS) confirmed the presence of potential PGP compounds, such as several types of siderophores, including desferrioxamine B and salicylic acid.
PVr_9 strain (Beijerinckia fluminensis), which has shown a higher growth-promoting activity in A. thaliana as well as significant antifungal activity against all phytopathogenic fungi used, was also tested for its ability to reduce salt stress in A. thaliana in vitro.
PVr_9-inoculated seedlings showed greater resistance to the adverse effects of salt than uninoculated seedlings in terms of morphological features. Furthermore, plants inoculated with PVr_9 had low contents of ROS, 8-oxodG, proline, soluble sugars and ABA. In plants inoculated with PVr_9, a significant decrease in Na+ was also observed in leaves and a corresponding increase in roots compared to uninoculated plants. qPCR analysis performed to test the expression of some genes involved in the response to salt stress revealed an increase in the expression of SOS1 and NHX1 in PVr_9-inoculated plants subjected to salt stress, while a decrease in the expression of several MYB genes involved in the response to stress signals was observed compared to uninoculated plants. These results open the possibility of using Beijerinckia fluminensis as a valuable biofertilizer and biopesticide also in field trials on agronomically important crops
Active gate drivers and loss modeling for the investigation of the controlled shoot-through phenomenon
No full textPower electronics is becoming more important due to the need for e-mobility and the
highly efficient and reliable systems required to beat climate change. The dual use of power
electronics converters as heaters will be extremely helpful.
In controlled shoot-through method, the controlled short-circuit is created to generate
heat within the power electronics switches. This is helpful to heat-up complete power electronic converter, creating a controlled short circuit without damaging the device. This technique is useful for using a power electronic converter as a heater as well as a heating device
in order to measure the on-state resistance of the MOSFET. The two-level (0, Vgs) active gate
driver proposed for the controlled shoot-through technique, on the other hand, had limitations. The limitations in terms of variable gate voltage, need to manually make changes in the
circuit to get different gate voltages etc.
The limitations are overridden by developing three-level (0, Vgs ′ , Vgs); where Vgs ′ is dynamic gate voltage in between zero to Vgs. The gate driver has a variable third level gate
voltage that can be as low as threshold voltage of the device, making it appropriate for testing SiC MOSFETs or GaN Devices. The controlled shoot-through was invented and tested
on the SiC MOSFET. Therefore, while developing three-level converter the SiC MOSFET is
considered.
Traditionally, the series Zener diode is used for the generation of the shoot-through voltage. The transient impedance of the series Zener diode affects the gate sourcing current and
results in a different gate voltage (Vgs) profile than without the series Zener diode condition.
Therefore, a loss model considering lost area needs to be considered. In the case of a NO
Zener diode in series, the shoot-through current is a square wave at low shoot-through current (self-heating does not start for low current). Therefore, the direct model can be used. If
the self-heating of the MOSFET considered, the on-state resistance of the MOSFET changes
due to the change in the junction temperature caused by drain current. The altered shape of the
shoot-through current and respective loss models are discussed in-depth. The mathematical
loss models considering self-heating are also developed.
The thesis concludes with the future application of the developed gate driver for active discharge of DC-link capacitor through power modules, power electronic converter as a
heater, extracting thermo-sensitive parameters by generating heat at the die level etc
Origins of the crossed corticostriatal projections
No full textÈ stato recentemente scoperto che nelle aree motorie frontali del macaco i neuroni corticostriatali (CSt) che proiettano al putamen motorio ipsilaterale possono essere equamente distribuiti negli strati III, V e VI (Borra et al., 2021), non si trovano quindi localizzati principalmente nel V strato, come indicato nei classici modelli di circuiteria dei GB. In aggiunta lo studio di Borra e coll. (2022) ha mostrato che lo striato nei primati non umani non è solo bersaglio di proiezioni dall’emisfero ipsilaterale, ma che le proiezioni al caudato e al putamen dall’emisfero controlaterale possono essere relativamente robuste. Nel presente studio abbiamo voluto verificare l’origine delle proiezioni CSt crociate, confrontandole con le proiezioni CSt ipsilaterali. Inoltre, abbiamo analizzato la dimensione e la forma cellulare in alcune zone corticali. I risultati di questo studio mostrano che la laminarità delle proiezioni CSt crociate è molto simile a quella trovata ipsilateralmente. I neuroni marcati non sono localizzati solo nel V strato, ma anche nel III e nel VI e possono essere una fonte importante di proiezioni CSt quantitativamente simili al V strato. L’analisi cellulare ha inoltre evidenziato differenze, in termini di forma, tra i neuroni CSt ipsilaterali e controlaterali: quest’ultimi sembrano essere più piccoli e più circolari
Esplorazione e comportamento emozionale in topi KO condizionali per NPY1r in relazione al sesso e all’ambiente materno precoce : un’analisi mediante componenti principali
No full textNPY1r has been largely studied for its capability not only to stimulate appetite-related behaviors, but also to modulate emotional behaviors and stress response. In humans and other animals, NPY1r appears to be involved in some psychopathological disorders such as Major Depression and Post-Traumatic Stress Disorder. The conditional NPY1r knockout mouse model can be a powerful tool to understand the behavioral response to stressful events and the role of this receptor in psychopathological disorders, as well as possible gene-environment interactions since a potential involvement of maternal care in the regulation of NPY expression has been hypothesized.
In the present study, knockout and wild type mice were fostered at birth to one of four different lactating dams’ strains characterized by different levels of maternal cares and as adults, were subjected to the Open Field test; some of them, following a stress event (pregnancy for females and Social Stress test for males), underwent a second test session. Mouse behaviors and other data, such as mean velocity or time spent in different areas of the arena, were analyzed. 367 mice from 9 different cohorts were analyzed.
Principal component analysis was conducted with the aim of reducing the dimensionality of the dataset; remarkably, in line with our expectation, all considered dependent variables were grouped in five principal components accordingly to the data’s covariance matrix, resulting in groupings in accordance with their inherent characteristics (one category for anxiety-like behaviors, one for vertical exploration, one for general exploration/activity, etc.).
Firstly, by means of a screening of the wild type population, strong sex effects were found, with females generally being more exploratory and less anxious than their male counterparts. This effect was also observed in relation to the foster dams’ strain: females reared by CD1dams were more exploratory than males, whereas mice reared by C57, FVB or BALB/c
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strains did not show such a sex difference. In a second analysis that took into account the effect of genotype, knockout mice were less exploratory and more anxious than wild type mice, and generally this was not related to sex or foster dams’ strain.
Under present conditions, our results showed how early maternal environment and NPY1 receptor are involved in the expression of anxiety-like behaviors. These results may help to better understand the etiopathogenesis of anxiety-related psychopathological disorders and help to develop future therapies to reduce psychopathological disorders.NPY1r è stato ampiamente studiato per via della sua capacità non solo di stimolare comportamenti appetitivi, ma anche di modulare comportamenti emozionali e risposte stressogene. Nell’essere umano e anche in altri animali, NPY1r sembrerebbe essere coinvolto in alcuni disturbi psicopatologici come la depressione maggiore ed il disturbo da stress posttraumatico. Lo studio del modello murino knockout condizionale per NPY1r può essere un valido strumento per comprendere la risposta comportamentale ad eventi stressogeni e il ruolo
di questo recettore in disturbi psicopatologici, così come la possibile interazione tra il gene e l’ambiente dato che è stato ipotizzato un potenziale coinvolgimento delle cure materne nella regolazione dell’espressione di NPY. In questo studio, topi knockout e wild type sono stati adottati alla nascita da uno dei quattro ceppi di madri allattanti caratterizzati da diversi livelli di cure materne e da adulti, sono stati sottoposti al test dell’Open Field, ed alcuni di essi sono stati sottoposti una seconda volta al test a seguito di un evento stressogeno (per le femmine la gravidanza ed i maschi la procedura di Social Stress). Sono stati analizzati vari comportamenti dell’animale e altri dati come la velocità media e il tempo speso nelle diverse aree dell’arena. Sono stati analizzati 367 topi di 9 coorti diverse.
È stata condotta un'analisi delle componenti principali con l'obiettivo di ridurre la dimensionalità del dataset; in linea con le nostre aspettative, le variabili dipendenti sono state accorpate in cinque componenti principali sulla base della matrice di covarianza dei dati di partenza, risultando raggruppate in accordo con le loro caratteristiche intrinseche (una categoria per comportamenti simil-ansiosi, una per esplorazione verticale, una per esplorazione/attività generale, ecc). In primo luogo, attraverso lo screening sui wild type si sono evidenziati forti effetti del sesso, per cui le femmine, in generale, risultavano essere maggiormente esplorative e meno ansiose dei maschi. Questo effetto si è presentato anche in relazione all’ambiente materno
precoce: le femmine adottate da CD1 risultavano più esplorative dei maschi, mentre topi
adottati dai ceppi C57, FVB o Balb/c non hanno mostrato una tale differenza sessuale. In una
seconda analisi che ha preso in considerazione anche l’effetto del genotipo si è osservato come
i topi knockout siano stati meno esplorativi e più ansiosi rispetto ai wild type; in generale non
è risultato essere in relazione al sesso oppure all’ambiente materno precoce. Al momento, i nostri risultati dimostrano come l’ambiente materno precoce ed NPY1r siano coinvolti nell’espressione di comportamenti simil-ansiogeni. Questo tipo di studi può aiutare a comprendere maggiormente l’eziopatogenesi di disturbi psicopatologici legati all’ansia e contribuire allo sviluppo di future terapie per ridurre questi disturbi
Evolutionary perspective on parental care and family conflict : a study on the role of psychosocial, sociodemographic factors and of the perception of similarity between parents and children
No full textSecondo i principi evoluzionistici, esistono delle pressioni selettive che agiscono in maniera diversa sul comportamento sessuale e genitoriale di molte specie, inclusa la nostra. Alla base di queste pressioni evolutive ci sono dei vincoli legati all’aspetto biologico delle asimmetrie sessuali nell’investimento riproduttivo maschile e femminile che si riflettono di conseguenza sull’investimento parentale. Le ragioni di queste differenze, che sono particolarmente pronunciate nei mammiferi, sono infatti da ricercare nella biologia della fecondazione, della gestazione e dell’allattamento obbligato per una donna. All’interno della nostra specie, l’ovulazione è nascosta e la fecondazione è interna, motivo per cui un uomo, al contrario di una donna, difficilmente ha la certezza assoluta riguardo la sua paternità biologica e deve, di conseguenza, ricercare diverse fonti di informazioni per stabilire in modo soggettivo la paternità genetica con i propri figli. Poiché la crescita della prole rappresenta un problema adattivo ricorrente e le cure parentali sono fondamentali per la sopravvivenza della prole, dal momento che la paternità non è certa, la selezione naturale avrebbe favorito l’evoluzione di alcuni meccanismi psicologici funzionali al riconoscimento dei parenti, e quindi dei propri figli. Uno di questi meccanismi è rappresentato dal riconoscimento basato sul matching fenotipico tra una serie di indici di somiglianza fenotipica, come per esempio la somiglianza dei tratti del viso e sulla base delle considerazioni evoluzionistiche ci si aspetta che gli uomini siano maggiormente sensibili rispetto alle donne ai segnali di paternità derivanti dalla somiglianza con i propri figli e che dirigano preferenzialmente l’investimento parentale in maggior misura quando la somiglianza percepita soggettivamente con i propri figli è maggiore. Al contrario, le donne non dovrebbero essere sensibili a questi segnali di somiglianza dato il vincolo biologico dell’investimento materno obbligato che rappresenta una fonte di certezza della parentela genetica che esse hanno con i propri figli e l’investimento materno risulterebbe quindi indipendente dalla somiglianza fenotipica con essi. According to evolutionary principles, there are selective pressures that act differently on the sexual and parental behavior of many species. At the basis of these evolutionary pressures there are a series of constraints linked to the biological aspect of sexual asymmetries in reproductive investment which consequently reflect on parental investment. The reasons for these differences, which are particularly pronounced in mammals, are to be found in the biology of fertilization, gestation and obligatory breastfeeding for a woman. Within our species, ovulation is hidden and fertilization is internal, so that a man, unlike a woman, hardly has absolute certainty regarding his biological paternity and, consequently, he had to seek different sources of information to subjectively establish genetic paternity with his offspring. Since the growth of offspring represents a recurrent adaptive problem and parental care is important for their offspring’s survival and because of uncertainty of paternity, natural selection would have favored the evolution of some psychological mechanisms functional to the recognition of parents, and therefore of the offspring. One of these mechanisms is represented by kin recognition through phenotypic matching between a series of cues of phenotypic similarity, such as the facial resemblance between parents and children. On the basis of evolutionary considerations, it is expected that men are more sensible than women to signals of paternity resulting from assessing similarity with their own children. Furthermore, we aspect that men preferentially direct a greater parental investment when the subjectively perceived similarity with children is higher. On the other hand, women should not be sensitive to these cues of similarity because of the biological constraint of obligatory maternal investment which represents a source of certainty of the genetic relatedness with their children, so that maternal investment would be independent of phenotypic similarity.
Self-checking systems for food safety and hygiene: compliance and development for certified food businesses
No full textL’elaborato si propone di analizzare l’efficienza dei Sistemi di Autocontrollo nelle aziende alimentari e di valutare l’effetto della loro implementazione mediante Sistemi di Certificazione volontari.
Nell’istituzione dei Piani di Autocontrollo aziendali sono racchiusi i concetti di qualità del prodotto, igiene, sicurezza alimentare e conformità alle normative, al fine di garantire la salubrità degli alimenti per tutelare la salute pubblica.
Il Piano di Autocontrollo è un documento scritto dell’azienda, che descrive le attività, i processi (dalla ricezione delle materie prime alla commercializzazione), i prodotti e che definisce le modalità di prevenzione e di controllo dei pericoli individuali. Ogni azienda ha l’obbligo di delegare l’OSA alla realizzazione del Piano, che va applicato in azienda per assicurare un controllo efficace e continuo dei pericoli per la sicurezza dell’alimento correlati con il prodotto e il processo. Vengono previsti dei sistemi di controllo interno, così l’azienda monitora e autocertifica i parametri di controllo, tale da poter dimostrare di aver operato in modo da minimizzare al massimo il rischio. Spesso le corrette prassi utilizzate dall’azienda vengono comunicate al consumatore finale sottoforma di etichetta, se ammesso, che rappresenta la forma di informazione fondamentale per i consumatori.
Per via delle richieste sempre più esigenti da parte dei consumatori, a fare da cuscinetto ai Sistemi di Autocontrollo aziendali, sono intervenuti numerosi accreditamenti/certificazioni privati volontari, basati su norme e standard internazionali certificabili, come ad esempio il BRC, l’IFS e le norme ISO. Rappresentano un potente strumento per le aziende, in quanto sono in grado di standardizzare le procedure e i processi per garantire un miglioramento continuo.
Questi sistemi innovativi apportano numerosi benefici alle aziende certificate: permettono di migliorare la sicurezza alimentare, di garantire la qualità del prodotto, di rispettare i requisiti normativi e legali, di favorire la fiducia dei consumatori, di incrementare l’accesso ai mercati internazionali, di assicurare l’efficienza operativa dell’azienda, di supportare le ispezioni pubbliche e di migliorare la competitività dell’azienda.The basis of this work is the analysis of the efficiency of Self-Checking Systems in food companies
and the evaluation of the effect of their implementation through voluntary Certification Systems.
The establishment of the companies Self-Checking Plans contains the concepts of product
quality, hygiene, food safety and compliance with regulations, in order to ensure the healthiness
of food to protect public health.
The Self-Checking Plan is a written document of the companies, which describes the activities,
the processes (from the reception of raw materials to the marketing), the products and which
defines the methods of prevention and control of individual hazards. Companies have the
obligation to delegate the OSA to the implementation of the Plan, which must be applied in the
company to ensure effective and continuous control of the food safety hazards related to the
product and the process. Internal control systems are provided, so the company monitors and
self-certifies the control parameters, so that it can demonstrate that it has operated in a way that
minimizes the risk as much as possible. The good practices used by the companies are often
communicated to the final consumer in the form of a label, if permitted, which represents the
basic information for consumers.
As a result of the increasingly demanding demands from consumers, to serve as a buffer for
corporate Self-Checking Systems, numerous voluntary private accreditations/certifications have
intervened, based on standards and certifiable international standards, such as BRC, IFS and ISO
standards. They are a powerful tool for businesses, as they are able to standardize procedures
and processes to ensure continuous improvement.
These innovative systems bring many benefits to certified food businesses: they improve food
safety, ensure product quality, comply with regulatory and legal requirements, foster consumer
confidence, increase access to international markets, ensure the operational efficiency of the
company, support public inspections and improve the company's competitiveness
Monitoring of the pregnant mare and related pathological conditions
No full textThe pregnancy in mammals is a physiological process that elapses between conception, that happens when the sperm fertilizes the oocyte forming the zygote, and parturition. Although most of pregnancies are uneventful, sometimes complications do happen. There are several pathological conditions concerning the pregnant mare which can cause illness or be lethal for both conceptus and mare.
The aim of this thesis is to describe carefully, based on the most recent literature, the most frequent pathological conditions of the pregnant mare, in order to prevent those diseases and know how to face them as well. On this purpose, it is very important to know the reproductive physiology and anatomy of the mare. Horse’s reproductive physiology shows particularities and specific characteristics that make this species appear unique compared to the others.
After a description of the mare’s reproductive anatomy and physiology, the main diseases and pathological conditions occurring during the gestational period of the mare will be treated in this work
Intrusion and Presence of the Author in Samuel Beckett’s “The Unnamable” and B. S. Johnson’s “Albert Angelo”
No full textOrganic dyes in condensed media: photophysics beyond gas phase
No full textThe simulation of dyes in condensed phase is a daunting, but rewarding task with enormous practical implications. For example, in the field or organic opto-electronics, understanding the interplay between an organic dye and the host in which it is dispersed may lead to the optimal tuning of the properties of the device, in a smart matrix approach. By its nature, the computational study of large disordered systems requires reliable approximations. To this aim, effective models for the dye and the medium are useful to rationalize the behaviour of complex systems.
The first part of this work addresses a very general issue, how the electronic degrees of freedom of the medium, i.e. the medium polarizability, affect the properties of the dye.
Three coupling schemes can be adopted to describe the interaction between the medium and an embedded dye:
- a non-adiabatic coupling that treats the medium degrees of freedom on the same foot as the electronic degrees of freedom of the dye;
- an adiabatic coupling that neglects the kinetic energy associated to the medium degrees of freedom; - an antiadiabatic coupling that consider an instantaneous response of the medium degrees of freedom to relevant events occurring in the dye.
The non-adiabatic approach is of course the most accurate, but, apart from its computational cost, it requires a detailed knowledge of the dynamics of the medium. The adiabatic and antiadiabatic approaches instead allow to renormalize away the medium degrees of freedom leading to effective solvation models, and, quite naturally apply when the medium degrees of freedom are much slower and faster, respectively, that the relevant degrees of freedom of the dye.
Despite their widespread use and computational efficiency, current implementations of implicit solvation models struggle to accurately describe the phenomenon, leading to a proliferation of approaches, that often yield widely different, and sometimes even unphysical, results.
Indeed, in current implementations of implicit solvation models, the electronic degrees of freedom of the medium are treated in the adiabatic approximation, and then fails to account for the medium polarizability.
To address this problem, in the framework of the reaction field model, we derive and validate an antiadiabatic Hamiltonian. We demonstrate that the adiabatic approximation to the medium polarizability, as implemented in widespread implicit solvation models, fails dramatically when applied to dyes for thermally-activated delayed fluorescence (TADF), where, depending on the system, an unphysical negative singlet-triplet gap is predicted.
The second part of this work is focused on modelling TADF dyes in liquid solvent and amorphous matrices. DMAC-TRZ is chosen as a representative system for twisted donor-acceptor dyes, and is modelled accounting for four diabatic electronic states, an effective molecular vibration and one effective torsional vibration. The model is parametrized ab initio and validated against experimental spectra in solution. Inter-system crossing (ISC) and reverse inter-system crossing (RISC) rates are estimated in a novel non-adiabatic approach that accounts for the anharmonicity of the torsional mode.
The dynamical response of the medium is considered with great care. Orientational relaxation in liquid solvents is fast (picoseconds) and the solvent is always in equilibrium with the dye. In organic matrices, most, but not all, orientational relaxation pathways are hindered, giving rise
to an intricate environment dynamics and static disorder. The model addresses both regimes allowing for the estimate of photophysical rates and the simulation of time resolved emission spectra
Impact of precision livestock farming on the management of dairy cattle farms
No full textLa zootecnia di precisione o, in inglese, Precision Livestock Farming (PLF) permette il monitoraggio dei singoli animali in tempo reale attraverso l’utilizzo di tecnologie che hanno l’obiettivo di migliorare la gestione aziendale e le performance dei singoli animali allevati.
In particolare, l’introduzione dei sistemi automatici negli allevamenti di bovini da latte è in continuo aumento e le innovazioni maggiormente presenti in questo tipo di aziende zootecniche sono i sistemi di mungitura automatica o AMS (Automatic milking system), i sistemi di alimentazione automatica (Automatic feeding system - AFS) ed i sistemi di avvicinamento della razione (spingiforaggio).
Lo scopo di questa tesi è quello di effettuare un’analisi dell’impatto di alcuni esempi di sistemi di PLF presenti in due aziende di bovine da latte nel Parmense e, in particolare, sono state esaminate quali sono state le principali motivazioni che hanno spinto gli allevatori ad affidarsi a queste nuove tecnologie automatiche per la mungitura e l’alimentazione.
È stato somministrato un questionario agli allevatori delle due aziende zootecniche in modo da poter evidenziare i principali cambiamenti messi in atto per l’installazione del sistema automatico ed è stata attuata un’analisi quantitativa del contenuto di grasso, proteine e cellule somatiche del latte di massa attraverso la valutazione di dati ottenuti dalle analisi del latte svolte dai caseifici riforniti e dai controlli funzionali raccolti dall’Associazione Regionale Allevatori (A.R.A.) Emilia-Romagna.
Da questo studio, a seguito dell’installazione dei sistemi automatici, sono stati riscontati, seppur nel breve termine, effetti positivi sulla gestione, sulla produzione e sul benessere animale, che hanno reso gli allevatori delle aziende soddisfatti della scelta fatta.Precision Livestock Farming (PLF) allows the monitoring of individual animals in real time using technologies that have the aim of improving the farms management and the performance of the single animals raised.
Particularly, the introduction of the automatic systems in dairy cattle farms is increasing and the major current innovations in this kind of livestock farms are the automatic milking systems (AMS), the automatic feeding systems (AFS) and the automatic feed pusher systems.
The purpose of this thesis is to carry out an analysis of the impact of some examples of PLF systems located in two dairy cattle farms situated in the province of Parma (Italy) and the main reasons that led farmers to rely on these new technologies of AMS and AFS were examined.
A questionnaire was administered to the farmers of the two livestock farms in order to highlight the main changes implemented for the installation of the automatic systems and a quantitative analysis of the fat, protein and somatic cells content of bulk milk was carried out, through the evaluation of data obtained from milk analyses carried out by the supplied dairies and from the functional checks collected from the Regional Farmers Association (Associazione Regionale Allevatori - A.R.A.) of the Emilia-Romagna.
From this study, after the installation of automatic systems, although in short time terms, positive effects on management, production and animal welfare were noted and the farmers are satisfied with the choice they made