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Immobilized Lipases on Spent Coffee Grounds for Enhanced and Sustainable Oil Hydrolysis
Free fatty acids (FFAs) play a fundamental role in industry as they are used in various sectors, from the food and pharmaceutical industry to biofuels production. Traditionally these molecules are produced employing aggressive chemicals and high temperatures [1], so, the use of immobilized lipases has recently emerged as a promising alternative. Also, the use of lignocellulosic wastes as lipase supports has aroused great interest [2] due to their wide availability, non-toxicity, renewability, etc. [3,4]. For these reasons, this work aimed to use spent coffee grounds (SCG) for the synthesis of solid biocatalysts capable of synthesizing FFAs from olive oil. Three solid biocatalysts derived from the immobilization of commercial lipase from Candida rugosa (C-CRL), lipase (isoenzyme 1) from Candida rugosa (Lip1), and lipase from Rhizopus oryzae (ROL) were studied. The solid biocatalysts were obtained through adsorption [5] on the treated waste material and immobilization parameters such as time, pH, and initial activity in the immobilization mixture were optimized for all three types of enzymes. The aim was to obtain the solid biocatalyst with the highest possible activity and the success of the immobilization procedures was evaluated by considering the activity recovery (%), immobilization efficiency (%), and activity of the solid biocatalyst (U/g). The synthesized solid biocatalysts were also characterized in terms of pH and thermal stability and each was found to be more stable than the starting free enzyme. Finally, all optimized solid biocatalysts were used in the hydrolysis of olive oil at 30 °C. Operational stability was also tested by repeating the hydrolysis procedure for several cycles and washing the solid biocatalyst after each use. All three solid biocatalysts demonstrated excellent operational stability, being able to be reused for up to 6 consecutive cycles. However, immobilized C-CRL showed the best hydrolysis percentage (23%) and the best specific Space-Time Yield (STY) [6] (8.8 g L−1 d−1).
In conclusion, this study addressed the pressing need for sustainable methods of raw material production using lipases immobilized on a lignocellulosic waste. The procedure was proved to be a promising alternative to traditional methods, offering advantages such as eco-friendliness and enzyme reuse
Institutions and Practices of Social Assistant: Monte di Pietà of Rome
The origins of the Monte di Pietà, or Mount of Piety, in Rome are well-known: established on the initiative of Giovanni Calvi, a commissioner of the Franciscan Order in Rome and approved by Pope Paul III, the Monte opened in 1539. This paper (based on original archival sources) will document the expansion of the Monte’s operations from the 16th century onwards. Particular attention will be devoted not just to ethical concerns but to the key countercyclical function played by pawnbroking activities at the lower end of the market, not just from an economic viewpoint but from a political perspective as well. Indeed the Monte played an important, albeit indirect, political role, at crucial junctures in the 17th and 19th century history of papal Rome: easy access to cheap Monte credit was instrumental in keeping internal peace and preventing the flaring up of social tensions
Normal fault architecture, evolution, and deformation mechanisms in basalts, Húsavik, Iceland. Impact on fluid flow in geothermal reservoirs and seismicity
Faults within layered basaltic sequences significantly influence hydrothermal fluid flow in shallow geothermal reservoirs and potentially during CO2 sequestration and storage. Nevertheless, their characterization regarding fault zone architecture, fluid flow, deformation mechanisms, and seismic potential remains underdeveloped. This study addresses this gap by integrating structural and microstructural observations with X-ray diffraction analyses of exposed normal-transtensional faults associated with the seismically active Húsavík-Flatey Fault in the Tjörnes Fracture Zone, Northern Iceland. Our findings demonstrate that the evolution of basalt-hosted normal-transtensional faults progresses through distinct stages: (1) low-displacement fault propagation from pre-existing cooling joints; (2) fault linkage via dilational jogs; (3) damage zone/fault core growth through brecciation and cataclastic processes; (4) shear localization along sharp slip surfaces; and (5) smearing of volcaniclastic interbeds along the principal fault plane. Evidence of shear localization, truncated clasts, and hydrothermal breccias/veins suggests repeated seismic slip events facilitated by overpressured fluids. Conversely, the presence of clay-rich foliated cataclasite indicates aseismic slips during interseismic periods. Slip along fault jogs, bends, geometric irregularities, and orientation changes causes the dilatant opening of the fault planes and extensional horsetail fractures at fault tips. These structures create main tabular zones for lateral movement of hydrothermal fluids parallel to the fault strike in shallow geothermal reservoirs situated in active extensional-transtensional tectonic settings. In addition, the dilational jogs and the intersection of horsetail veins with the hosting faults may define linear zones of high structural permeability and intense localized fluid flow parallel to the σ2 paleostress orientation and finally mineral precipitation. The results of this study can be utilized to improve models of geothermal fluid flow for enhanced recovery in basaltic reservoirs and assess seismic risk in basaltic faults
Parsec-scale cosmic-ray ionisation rate in Orion
Context. Cosmic rays are a key component of the interstellar medium because they regulate the dynamics and chemical processes in the densest and coldest regions of molecular clouds. Still, the cosmic-ray ionisation rate of H2 (ζH2ion) is one of the most debated parameters characterising molecular clouds because of the uncertainties in the adopted chemical networks and analysis techniques.
Aims. This work aims to homogeneously estimate the ζH2ion at parsec scales towards the Orion Molecular Clouds OMC-2 and OMC-3. We explore the change in ζH2ion across a whole star-forming region by probing a range of column densities that has never been explored before. The significant increase in statistics obtained by studying an entire region allows us to place stronger constraints on the range of ζH2ion values and exploit its connection with the physical properties of the interstellar medium.
Methods. The most recent ζH2ion estimates are based on o-H2D+, which is a direct product of the interaction between cosmic rays and H2 in cold clouds. Since observations of o-H2D+ are challenging, we proxy its abundance through CO depletion by employing C18O (2–1) observations towards OMC-2 and OMC-3, taking advantage of the existing correlation between the two parameters. Using additional observations of HCO+ (1–0) and DCO+ (3–2), we determine the deuteration fraction, and we finally derive the map of ζH2ion in these two regions.
Results. The C18O depletion correlates with both the total column density of H2 and the N2H+ emission across OMC-2 and OMC-3. The obtained depletion factors and deuteration fractions are consistent with previous values obtained in low- and high-mass star-forming regions. These two parameters additionally show a positive correlation in the coldest fields of our maps. We derive cosmic-ray ionisation rates of ζH2ion ~ 5 × 10-18-10-16s-1. These values agree well with previous estimates based on o-H2D+ observations. The ζH2ion also shows a functional dependence on the column density of H2 across a full order of magnitude (~1022–1023 cm−2). The estimated values of ζH2ion decrease overall for increasing N(H2), as predicted by theoretical models.
Conclusions. The results delivered by our approach are comparable with theoretical predictions and previous independent studies. This confirms the robustness of the analytical framework and promotes CO depletion as a viable proxy of o-H2D+. We also explore the main limitations of the method by varying the physical size of the gas crossed by the cosmic rays (i.e. the path length). By employing a path length obtained from low-resolution observations, we recover values of the ζH2ion that are well below any existing theoretical and observational prediction. This discrepancy highlights the need for interferometric observations in order to reliably constrain the ζH2ion at parsec scales as well
Accelerating network resource allocation in LoRaWAN via distributed big data computing
LoRaWAN is a Low Power infrastructure for the Internet of Things (IoT) with a centralized architecture where a single node, the network server, handles all data collection and network management decisions. Given the proliferation and widespread adoption of IoT devices, it becomes essential to incorporate Big Data paradigms at the network server to efficiently manage the enormous volumes of data. In this paper, we introduce a distributed and high-performance methodology for resource allocation in dense LoRaWAN networks, addressing the scalability issues that arise when processing large amounts of information from IoT devices, such as radio link quality. Our contributions establish the groundwork for a distributed implementation of the EXPLORA-C allocation strategy, capable of efficiently operating in large-scale networks. We present two approaches for implementing this distributed scheme: the Multi-Thread (MT) scheme and the Fully-Distributed (FD) scheme. Furthermore, we demonstrate the feasibility of this distributed implementation on top of the NebulaStream stream-based end-to-end data management platform. To validate the proposed approach, we exploit our co-simulation framework, EXPLoSIM, where the distributed implementation is fed with data from a simulated LoRaWAN network. This validation shows significant savings in execution time, latency, and scalability. Additionally, we generalize the concept by decomposing a centralized data aggregation scheme into a chain of stream-processing operators, which can be dynamically allocated across device, Edge, and Cloud levels. In the best scenario, our approach improves metrics such as execution time and data reduction by over 90% when compared to its centralized operation
Sorcin in Cancer Development and Chemotherapeutic Drug Resistance
Simple Summary Sorcin is a protein that helps cells handle calcium. It is often found in high amounts in cancer cells, especially those that are resistant to treatment. Sorcin plays a key role in cancer growth and spread by helping cancer cells avoid the toxic effects of chemotherapy drugs, acting on multiple cellular mechanisms. This review will explore sorcin's structure and function, its role in cancer, and how we might be able to target it for new treatments.Abstract SOluble Resistance-related Calcium-binding proteIN (sorcin) earned its name due to its co-amplification with ABCB1 in multidrug-resistant cells. Initially thought to be an accidental consequence of this co-amplification, recent research indicates that sorcin plays a more active role as an oncoprotein, significantly impacting multidrug resistance (MDR). Sorcin is a highly expressed calcium-binding protein, often overproduced in human tumors and multidrug-resistant cancers, and is a promising novel MDR marker. In tumors, sorcin levels inversely correlate with both patient response to chemotherapy and overall prognosis. Multidrug-resistant cell lines consistently exhibit higher sorcin expression compared to their parental counterparts. Furthermore, sorcin overexpression via gene transfection enhances drug resistance to various chemotherapeutic drugs across numerous cancer lines. Conversely, silencing sorcin expression reverses drug resistance in many cell lines. Sorcin participates in several mechanisms of MDR, including drug efflux, drug sequestering, cell death inhibition, gene amplification, epithelial-to-mesenchymal transition, angiogenesis, and metastasis. The present review focuses on the structure and function of sorcin, on sorcin's role in cancer and drug resistance, and on the approaches aimed at targeting sorcin
Le opportunità e le sfide dei tepe millenari; ricostruzione del passato, legame col presente e attenzione verso il futuro ad Arslantepe, Malatya. Binlerce yıllık höyüğün, sunduğu olasılıklar ve zorluklar; Malatya Arslantepe’de geçmişin yeniden inşa edilmesi, günümüzdeki yerine ve geleceğine dair.
L'articolo racconta le attività della missione archaeologica italiana in Anatolia Orientale, sia per quanto riguarda lo scavo e la ricerca scientifica, sia entrando nel merito delle attività di restauro e di terza missione
Self-feeding and communicative development during the first two years of life: concurrent and longitudinal associations
Early exposure to a baby-led weaning approach (BLW) encourages infants to actively participate in the
feeding process, fostering the development of essential motor skills. By allowing them to manipulate,
grasp, and chew a variety of age-appropriate foods, infants exposed to the BLW acquire a greater
degree of autonomy in their eating experiences (Rapley, 2005, 2018). This contrasts with the parent-led
weaning approach (PLW), where the emphasis on being spoon-fed puréed foods by a parent may limit
the opportunities for infants to explore different textures and tastes independently. Notably, the
developmental acquisitions in infants’ motor skills may act as catalysts, shaping the caregiver-infant
interactions during the daily feeding routines from the beginning of the weaning period and exerting an
impact on the emergence of intentional communication by the end of the first year of life (e.g., Iverson,
2021).
In the present study, we observed a typical meal of 182 infants when they were 12 months of age, in
order to investigate: i) whether infants’ more advanced independent eating skills were associated with
their emerging gestural and vocal communication, and ii) the relations between mothers’ child-directed
speech during the meal and infants’ gestural and vocal production. We also examined the potential
cascading effects of independent eating skills and mothers’ child-directed speech on infants’ language
development at 18 and 24 months of age. Building on prior research (Camaioni et al., 2003; Weisleder &
Fernald, 2013), we developed a coding scheme in order to capture infants’ gestures and vocalizations, as
well as all utterances and words directed towards the infants by individuals present during the meal. In
addition to the observational measurements, mothers completed: i) a socio-demographic questionnaire,
encompassing potentially relevant information, such as infants’ age and gender, duration of exclusive
breastfeeding, and the use of the pacifier, ii) the Italian short form of the MacArthur-Bates
Communicative Development Inventories (Words and Gestures) (SF-MCDI) to assess comprehension,
productive vocabulary, and gestures (Caselli et al., 2015), and iii) the Developmental ProfileTM 3 (Alpern
2007), from which we derived a fine-motor skill score. When infants were 18 and 24 months-old,
mothers completed again the SF-MCDI (Words and Sentences).
Regression analyses revealed that infants who engaged in self-feeding more frequently during meals at
12 months were also more likely to exhibit deictic gestures (i.e., pointing, showing, offering, requesting
and taking) and to produce a greater number of vocalizations than infants who self-fed less often.
Moreover, we found that the proportion of mothers’ child-directed utterances was positively associated
with infants’ production of gestures, vocalizations, and words. We also found that infants’ fine-motor
skills were positively related to their comprehension and gestures production at 12 months. Finally,
longitudinal analyses showed that infants’ self-feeding at 12 months was positively associated with their
ability to produce sentences at 24 months.
Overall, these findings underscore the interplay between self-feeding, maternal child-directed speech,
and the trajectory of infants’ communicative development. The study highlights the importance of
considering mealtime practices and interactions, as well as motor skill development, in understanding
and promoting early language acquisition
La tradizione manoscritta delle chiose a ‘Inferno’ e ‘Purgatorio’ dell’Anonimo Lombardo
Studio della tradizione manoscritta delle chiose latine a Inferno e Purgatorio dell'Anonimo Lombardo