106,297 research outputs found
MID1 mutations in patients with X-linked Opitz G/BBB syndrome
No full textMutations in the MID1 gene are responsible for the X-linked form of Opitz G/BBB syndrome (OS), a disorder that affects the development of midline structures. OS is characterized by hypertelorism, hypospadias, laryngo-tracheo-esophageal (LTE) abnormalities, and additional midline defects. Cardiac, anal, and neurological defects are also present. The expressivity of OS is highly variable, even within the same family. We reviewed all the MID1 mutations reported so far, in both familial and sporadic cases. The mutations are scattered along the entire length of the gene and consist of missense and nonsense mutations, insertions and deletions, either in-frame or causing frameshifts, and deletions of either single exons or the entire MID1 coding region. The variety of described mutations and the lack of a strict genotype-phenotype correlation confirm the previous suggestion of the OS phenotype being caused by a loss-of-function mechanism. However, although a specific mutation cannot entirely account for the observed phenotype, we observed preferential association between some types of mutation and specific clinical manifestations, e.g., brain anatomical defects and truncating mutations. This may suggest that the pathogenetic mechanism underlying the OS phenotype is more complex and may vary among the affected organs
Photo-renewable engineered sensor based on silica, silver nanoparticles and titania
No full textElectrode surface passivation and fouling are important challenges in electroanalysis when using modified electrodes in complex matrices, especially in the biomedical and environmental fields [1-2].
In order to overcome such problems, the production of highly engineered ad hoc designed devices could provide really effective sensors [2]. In particular, a reliable and reusable sensor, that could be cleaned by a simple irradiation with UV or solar light, could be perfect for this purpose.
In this context, a three-layered transparent electrode, in which silver nanoparticles are embedded between a bottom silica and a top titania layer is developed [3-4]. Such structure confers to the device multifunctional properties which can be conveniently used in the detection and quantification of some neurotransmitters: dopamine, norepinephrine and serotonin.
The sensor is thoroughly investigated by structural, morphological and electrochemical characterizations in order to understand the role of each component with the aim to improve the robustness and efficiency of the electroanalytical system. In particular, the size distribution of silver nanoparticles, the device architecture and surface homogeneity are inspected by electron microscopy. As confirmed by X-ray diffraction the overlayer is made of anatase (the active polymorph of titanium dioxide), capable of photodegrading model contaminants. Furthermore, electrochemical techniques (cyclic voltammetry and electrochemical impedance spectroscopy) revealed that a highly ordered distribution of silver nanoparticles constitutes the active analytical core of the device, allowing easier electron transfer and better quantification of the analytes.
The system presents good sensing performances, reaching low detection limits even in the presence of typical interferents such as ascorbic and uric acids. Moreover, the titania photoactive top layer allows the complete recovery of the device performance in terms of sensitivity after a fast and simple UV-A cleaning step, affordable with different UV sources. In particular, three lamps (different in terms of power and wavelength) were tested, reaching the total removal of the contaminants in 10-15 minutes [5]. This “self-cleaning” property, combined with a remarkable resistance against aging and ease of use, allows to employ the sensor also for detection in real matrixes, such as liquor and serum.
ACKNOWLEDGEMENTS
The Authors would like to thank MIUR (Ministero dell’Istruzione, dell’Università e della Ricerca) for the fundings in the framework of the PRIN 2012 Project (20128ZZS2H)
REFERENCES
[1] C.M.A. Brett, Pure Appl. Chem. 73, 2001, pp 1969–1977.
[2] C.M. Welch, R.G. Compton, Anal. Bioanal. Chem. 384, 2006, pp 601–619.
[3] G. Maino, D. Meroni, V. Pifferi, L. Falciola, G. Soliveri, G. Cappelletti, S. Ardizzone, J. Nanoparticle Res. 15, 2013, pp 2087.
[4] G. Soliveri, V. Pifferi, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, K. Sparnacci, L. Falciola, Analyst 140, 2015, 1486-1494.
[5] V. Pifferi, G. Soliveri, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, L. Falciola, RSC Advances, 5, 2015, 71210-71214
Innovative engineered sensors based on silica, silver nanoparticles and titania with self-cleaning features
No full textPassivation of the electrode surface and fouling are important challenges in electroanalysis during the use of modified electrodes in complex matrices, especially in the biomedical and environmental fields (Soliveri et al., 2015). The production of highly engineered devices, ad hoc designed for specific applications, could overcome such problems, accessing really effective sensors. A performing, reliable and reusable sensor, that could be cleaned by a simple irradiation with UV or solar light, would perfectly match this goal.
In this context, a three-layered transparent electrode, in which silver nanoparticles are embedded between a bottom silica and a top titania layer (Maino et al., 2013 and Welch and Compton, 2006), was developed. Such structure confers to the device multifunctional properties for a complex biomedical challenge: the detection and quantification of catecholamine neurotransmitters. The sensor was thoroughly investigated in order to understand the role of each component with the aim of making the device a robust and efficient electroanalytical system.
The overlayer was made of anatase (the active polymorph of titanium dioxide) as confirmed by X-ray diffraction and by measuring the photodegradation of model contaminants. The size distribution of silver nanoparticles, the device architecture and surface homogeneity were inspected by electron microscopy. Electrochemical techniques (cyclic voltammetry and electrochemical impedance spectroscopy) revealed that a highly ordered distribution of silver nanoparticles constitutes the active core of the device, allowing easier electron transfer and better quantification of the analytes even in the presence of conventional interferents, e.g. ascorbic and uric acid. Titania photoactive top layer allowed total recovery of the device performance in terms of sensitivity after a fast and simple UV-A cleaning step, affordable with different UV sources. This self-cleaning property, combined with a remarkable resistance against aging and ease of use, allows to employ the sensor also in on-field and remote applications.
Maino G., Meroni D., Pifferi V., Falciola L., Soliveri G., Cappelletti G., Ardizzone S. (2013). Electrochemically assisted deposition of transparent, mechanically robust TiO2 films for advanced applications. J. Nanoparticle Res., 15, 2087.
Soliveri G., Pifferi V., Panzarasa G., Ardizzone S., Cappelletti G., Meroni D., Sparnacci K., Falciola L. (2015). Self-cleaning properties in engineered sensors fordopamine electroanalytical detection. Analyst, 140, 1486-1494.
Welch C. M., Compton R. G. (2006). The use of nanoparticles in electroanalysis: a review. Anal. Bioanal. Chem., 384, 601–619
Self-cleaning properties of a silica/silver nanoparticles/titania sandwich sensor
No full textOne of the main challenges faced during electroanalysis of complex matrices is represented by fouling and passivation of the electrode surface, especially in the fields of biomedical and environmental trace analysis [1], where sophisticated and highly engineered sensors have to be used in order to increase sensitivity and lower detection limits. These sensors can not be cleaned by conventional mechanical or electrochemical procedures, since these methods could affect the integrity of the active layer. In order to overcome these problems, the production of highly engineered reliable and reusable devices, designed ad hoc for specific applications, which could be simply cleaned by irradiation with UV light, would be an interesting step beyond the current state of the art.
In this context, a three-layered transparent electrode, in which silver nanoparticles are embedded between a bottom silica and a top titania layer [2, 3] was designed, prepared and characterized. The device structure is meant to confer multifunctional properties for a complex biomedical challenge: the detection and quantification of catecholamine neurotransmitters. The key role of each component of the device was thoroughly investigated to demonstrate the robustness and efficiency of the final sensor. In particular, the size distribution of silver nanoparticles, the device architecture and surface homogeneity were inspected by electron microscopy. The cleaning overlayer was made of the active polymorph of titanium dioxide (anatase), as confirmed by X-ray diffraction and by model contaminants photodegradation measurements. Electrochemical techniques (cyclic voltammetry and electrochemical impedance spectroscopy) revealed that an highly ordered distribution of silver nanoparticles is the active core of the device, allowing easier electron transfer and better quantification of the analytes even in the presence of conventional interferents, e.g. ascorbic acid and uric acid in human fluids.
The high photoactivity of titania top layer allowed total recovery of the device performance in terms of sensitivity after a fast (less than 20 min) UV cleaning step, affordable with different UV-A sources. This self-cleaning property, combined with a remarkable resistance against ageing, allows to employ the sensor also in on-field and remote applications.
References
[1] C. M. Welch and R. G. Compton, Anal. Bioanal. Chem. 2006, 384, 601–619.
[2] G. Maino, D. Meroni, V. Pifferi, L. Falciola, G. Soliveri, G. Cappelletti, S. Ardizzone, J. Nanoparticle Res. 2013, 15, 2087.
[3] G. Soliveri, V. Pifferi, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, K. Sparnacci, L. Falciola, Analyst 2015, 140, 1486
Self-cleaning features of an innovative engineered sensor based on silica, silver nanoparticles and titania
No full textPassivation of the electrode surface and fouling are important challenges in electroanalysis during the use of modified electrodes in complex matrices, especially in the biomedical and environmental fields [1-2].
In order to overcome such problems, the production of highly engineered ad hoc designed devices could access really effective sensors [2]. In particular, a performing, reliable and reusable sensor, that could be cleaned by a simple irradiation with UV or solar light, would be perfect for this purpose.
In this context, a three-layered transparent electrode, in which silver nanoparticles are embedded between a bottom silica and a top titania layer was developed [3-4]. Such structure confers to the device multifunctional properties for a complex biomedical challenge: the detection and quantification of catecholamine neurotransmitters. The sensor was thoroughly investigated by structural, morphological and electrochemical characterizations in order to understand the role of each component with the aim to improve the robustness and efficiency of the electroanalytical system.
The overlayer was made of anatase (the active polymorph of titanium dioxide) as confirmed by X-ray diffraction and by measuring the photodegradation of model contaminants. The size distribution of silver nanoparticles, the device architecture and surface homogeneity were inspected by electron microscopy. Electrochemical techniques (cyclic voltammetry and electrochemical impedance spectroscopy) revealed that a highly ordered distribution of silver nanoparticles constitutes the active core of the device, allowing easier electron transfer and better quantification of the analytes even in the presence of conventional interferents, e.g. ascorbic and uric acid. Titania photoactive top layer allowed total recovery of the device performance in terms of sensitivity after a fast and simple UV-A cleaning step, affordable with different UV sources. This self-cleaning property, combined with a remarkable resistance against aging and ease of use, allows to employ the sensor also in on-field and remote applications.
References
1. C.M.A. Brett, Pure Appl. Chem. 73, 2001, pp 1969–1977.
2. C.M. Welch, R.G. Compton, Anal. Bioanal. Chem. 384, 2006, pp 601–619.
3. G. Maino, D. Meroni, V. Pifferi, L. Falciola, G. Soliveri, G. Cappelletti, S. Ardizzone, J. Nanoparticle Res. 15, 2013, pp 2087.
4. G. Soliveri, V. Pifferi, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, K. Sparnacci, L. Falciola, Analyst 140, 2015, 1486-1494
TRIM E3 Ubiquitin Ligases in Rare Genetic Disorders
No full textThe TRIM family comprises proteins characterized by the presence of the tripartite motif composed of a RING domain, one or two B-box domains and a coiled-coil region. The TRIM shared domain structure underscores a common biochemical function as E3 ligase within the ubiquitination cascade. The TRIM proteins represent one of the largest E3 ligase families counting in human more than 70 members. These proteins are implicated in a plethora of cellular processes such as apoptosis, cell cycle regulation, muscular physiology, and innate immune response. Consistently, their alteration results in several pathological conditions emphasizing their medical relevance. Here, the genetic and pathogenetic mechanisms of rare disorders directly caused by mutations in TRIM genes will be reviewed. These diseases fall into different pathological areas, from malformation birth defects due to developmental abnormalities, to neurological disorders and progressive teenage neuromuscular disorders. In many instances, TRIM E3 ligases act on several substrates thus exerting pleiotropic activities: the need of unraveling disease-specific TRIM pathways for a precise targeting therapy avoiding dramatic side effects will be discussed
Artifact-Driven Process Monitoring: A Viable Solution to Continuously and Autonomously Monitor Business Processes
No full textBusiness process monitoring aims at identifying how well running processes are performing with respect to performance measures and objectives. By observing the execution of a process, process monitoring is also responsible for creating process traces, which can be subsequently used by process mining algorithms to gain further insights on the process. Among the various monitoring solutions, artifact-driven monitoring has been proposed as a viable solution to continuously and autonomously monitor business processes. By monitoring the changes in the physical and virtual objects (i.e., artifacts) participating in the process, artifact-driven monitoring can autonomously generate traces that include events related to semi-automatic and manual tasks. Also, by relying on a declarative representation of the process to monitor, artifact-driven monitoring can detecting violations in the execution flow as soon as they occur. In addition, artifact-driven monitoring can identify the process elements affected by a violation, and it can continue monitoring the process without human intervention. This tutorial paper will firstly provide an introduction to process monitoring, and the recent advancements in this field. Then, an overview on how artifact-driven monitoring works will be provided
Silver nanoparticles/nanostructured TiO2 interface: a photo-renewable “silver-ions electrode” for neurotransmitters detection
No full textSilver nanoparticles were embedded in a TiO2 (anatase polymorph) photoactive layer in a sandwich-like nanostructured electrode. [1-2]
The device was (photo)electrochemically characterized by cyclic voltammetry and electrochemical impedance spectroscopy.
In comparison with literature data on electrodes modified with silver nanoparticles [3-5], the new sensor presents a pronounced electrocatalytic effect on the silver oxidation peak together with a great increase in the current intensity.
Parallel plane-wave DFT calculations, performed using the VASP code [6], described the composite junction as a distorted bulk Ag structure, commensurate with the periodicity of the (101) face of the I41/amd TiO2 anatase polymorph. The silver atoms close to the semiconductor were found to gain a partially positive charge, quickly decreasing with the distance from the TiO2 surface.
Comparing the theoretical and experimental results it could be concluded that the device may be considered as a “positively charged silver nanoparticles-based electrode”, with positively ionized surface silver atoms protected by the titania layer, which holds a partial negative charge.
The final sensor performed efficiently in the electroanalytical determination of some neurotransmitters (e.g. dopamine, norepinephrine and serotonin) in simulated biological matrices (liquor, serum and urine). The optimized analytical methodology is not only characterized by high sensitivity and low detection limits (around 0.03 μM, which makes it appealing for clinical purposes), but also by high selectivity in the presence of high concentrations of conventional interferents (uric and ascorbic acids).
Last but not least, the fouling and passivation of the electrode surface, an unavoidable drawback during the detection of this kind of analytes, could be easily overcome by irradiating the device with UVA-light, which restored the initial sensor sensitivity. The photo-renewability allows to reactivate the sensor on site, i.e. directly in solution, to yield a system capable of working in continuous, able to be used in an integrated monitoring system.
References
[1] G. Soliveri, V. Pifferi, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, K. Sparnacci, L. Falciola, Analyst, 140, (2015), 1486 – 1494.
[2] V. Pifferi, G. Soliveri, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, L. Falciola, RSC Advances, 5, (2015), 71210 – 71214.
[3] O. S. Ivanova, F. P. Zamborini, J. Am. Chem. Soc., 132, (2010), 70–72.
[4] G. Chang, J. Zhang, M. Oyama, K. Hirao, J. Phys. Chem. B, 109, (2005), 1204-1209.
[5] S.E. Ward Jones, F.W. Campbell, R. Baron, L. Xiao, R.G. Compton, J. Phys. Chem. C, 112, (2008), 17820–17827.
[6] G. Kresse, J. Furthmüller, Phys. Rev. B, 54:11169, (1996).
Acknowledgements
This work has been supported by Fondazione Cariplo (Milano, Italy), grant no. 2014-1285. We acknowledge the CINECA and the Regione Lombardia award under the LISA initiative (grant SURGREEN) for the availability of high performance computing resources. We also thank the Chemistry Department for funding through the Development Plan of Athenaeum grant – line B1 (UNIAGI 17777)
Trusted artifact-driven monitoring of business processes using blockchains
No full textHaving a reliable business process monitoring platform is important to promptly detect and react to violations during process execution. Typically, when processes span among multiple organizations or require manual activities, a relationship of trust must be established among participants to obtain meaningful results. Also, when a violation is detected, most monitoring platforms report it and expect participants to stop executing the process and to manually solve it before resuming the execution. Trusted artifact-driven monitoring tries to overcome these limitations. By relying on a declarative model of the process to monitor, rather than an imperative one, trusted artifact-driven monitoring can continue to monitor the process even after a violation occurred. Also, it relies on events coming from artifacts (i.e., physical or virtual objects) participating in the process to infer when activities are executed. Finally, to guarantee the immutability of monitoring information once they are produced, it relies on a blockchain-based architecture to store and retrieve this information
Victimisation and Masculinity in the Polarisation of Misogynist Incel Discourse: Bending van Dijk’s Ideological Square (1998)
No full textIn recent years, the incel community – a portmanteau of involuntary celibate, indicating young men who are unable to have a romantic or sexual relationship despite their efforts – has interested discourse studies scholars for their highly discriminatory discourses against minority groups (Prażmo, 2020). A close-knitted community, in their forums incels have developed a distinctive language characterized by neologisms and extensive identity construction strategies (Waśniewska, 2020). By framing their condition as a discrimination based on a supposed genetic inferiority making them unworthy of accessing sex, incels position their social group in opposition to most of society and, above all, to women. Discourse is polarized using an ‘us vs them’ rhetoric that would appear at first sight to fit in with van Dijk’s (1998) ideological square, which has long provided a solid framework for investigating in-group/out-group discourse dynamics. But while the ‘us vs them’ rhetoric conventionally pitches a positive ‘us’ versus a negative ‘them’, Scotto di Carlo (2023) points out that incels seem to breach this pattern. However, I argue that, rather than breaching it, incels make a peculiar use of the ideological square by bending it through narratives of victimization and weaponized subordinate masculinity (Halpin, 2022). Using critical discourse analysis (van Dijk, 1995; 2015; Lazar, 2005; Baxter, 2018) on a corpus of incel forum posts (collected from incel.is and incel.net) this paper aims to investigate how this rhetorical strategy allows them to reproduce harmful representations of women and enforce misogynist discourse practices typical of patriarchal societies
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