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The mammalian DNA replication timing (RT) program is crucial for the proper functioning and integrity of the genome. The best-known mechanism for controlling RT is the suppression of late origins of replication in heterochromatin by RIF1. Here, we report that in antigen-activated B lymphocytes, RIF1 binds predominantly to early-replicating active chromatin, regulates early origin firing and promotes early replication. RIF1 has a minor role in gene expression and genome organization in B cells. Furthermore, we find that RIF1 functions in a complementary and non-epistatic manner with minichromosome maintenance (MCM) proteins to establish early RT signatures genome-wide and, specifically, to ensure the early replication of highly transcribed genes. These findings reveal new layers of regulation within the B cell RT program, driven by the coordinated activity of RIF1 and MCM proteins.

In this article, we share our experience related to the new photo-injector commissioning at the SPARC_LAB test facility. The new photo-injector was installed into an existing machine and our goal was not only to improve the final beam parameters themselves but to improve the machine handling in day-to-day operations as well. Thus, besides the pure beam characterization, this article contains information about the improvements, that were introduced into the new photo-injector design from the machine maintenance point of view, and the benefits, that we gained by using the new technique to assemble the gun itself.

The breakthrough provided by plasma-based accelerators enabled unprecedented accelerating fields by boosting electron beams to gigaelectronvolt energies within a few centimeters [1-4]. This, in turn, allows the realization of ultracompact light sources based on free-electron lasers (FELs) [5], as demonstrated by two pioneering experiments that reported the observation of self-amplified spontaneous emission (SASE) driven by plasma-accelerated beams [6,7]. However, the lack of stability and reproducibility due to the intrinsic nature of the SASE process (whose amplification starts from the shot noise of the electron beam) may hinder their effective implementation for user purposes. Here, we report a proof-of-principle experiment using plasma-accelerated beams to generate stable and reproducible FEL light seeded by an external laser. FEL radiation is emitted in the infrared range, showing the typical exponential growth of its energy over six consecutive undulators. Compared to SASE, the seeded FEL pulses have energies 2 orders of magnitude larger and stability that is 3 times higher.

A viable solution to environmental problems related to pollutant emissions from internal combustion engine vehicles is electric cars. The main problem with electric vehicles, which also limits their widespread use, is due to lithium batteries and in particular their thermal control. Thermal control of lithium batteries is an extremely topical issue since it is not only related to the performance of the vehicles on which they are mounted, but also to the safety of the vehicles and drivers. For this purpose, both factors internal to the battery itself and external causes such as environmental conditions must be considered. In this work, a thermal control system based on metal foams partially filled by the phase change material (PCM) was numerically investigated as a possible application for cooling lithium batteries. For this purpose, a two-dimensional numerical model was constructed in which the PCM partially fills the metal foam. The finite volume method used through the ANSYS Fluent code was used for the governing equations, which are written assuming local thermal equilibrium. Several cases were simulated for different values of the external convective heat transfer coefficient. The results obtained, are reported in terms of temperatures and liquid fractions. Comparisons with partially filled and totally filled cases by PCM in the thermal control system are reported to show the advantage obtained, in terms of thermal control, with a composite system of metal foam and PCM.

In this paper a numerical entropy generation analysis on confined slot impinging jets made up of a totally filled configuration of metal foam in mixed convection is presented. A two-dimensional domain is assumed and several Peclet numbers (equal to 350, 750, 1500) are considered. Rayleigh numbers is imposed equal to 30000. The employed working fluids are pure water or Al2O3/water based nanofluids. The nanoparticle volume concentrations are in a range from 0% to 4% and the nanoparticle diameter is varied in a range from 20 nm to 80nm. The target surface is characterized by a constant temperature, estimated starting to the value of Rayleigh number. The distance of the target surface is five times greater than the slot jet width. The thermal and fluid dynamic properties of nanofluids are evaluated by a single-phase model method. The model of local thermal non equilibrium (LTNE) is considere in order to simulate the behavior of the metal foam characterized by a number of pores per inch (PPI) equal to 5, 10, 20, 40 and a porosity around 0.90. The data in terms of total global entropy generation related to the thermal and viscous effects are given Results show increasing values of the total entropy generation for increasing values of Peclet number and nanoparticle concentration. This behaviour is more evident at higher Peclet number values. In addition, the total entropy generation increases with the increase of PPI in corresponding to the same porosity value.

In the present work, a vertical shell and tube Latent Heat Thermal Energy Storage System is analyzed. The cylinder is filled with phase change material and parts of metal foam. The inner face of the cylinder is corrugated, and it is assumed a constant temperature over the melting temperature of the paraffin wax to simulate the heat transfer. The external surface loses heat to the outside and the top and bottom surfaces are adiabatic. Paraffin wax is used as phase change material that melts over a range of temperatures and has a high latent heat of fusion. The thermal conductivity of the phase change material is low and due to this, it is enhanced with metal foam. In this numerical simulation, it is used the aluminum foam. Enthalpy-porosity theory is used to simulate the phase transition process, and the Local Thermal Equilibrium and Darcy-Forchheimer models are used to examine heat transport between the paraffin and the metal foam. Using the commercial code Ansys-Fluent, the governing equations’ solutions are calculated. In the paper, it is considered different conductivity variations on the external wall and the distinct filling ratio of metal foam. The melting time, enthalpy stored, and energy loss from the numerical simulations of the LHTESS charging phase are provided as a function of time and evaluated.

The project realize an idea from students of Scientific High school involved in a multidisciplinary path focused on “ONE HEALTH” approach and “ENVIRONMENTAL EDUCATION” After skill buildings webinars the students decided to build a survey in order to Raise awareness about how any individual behavior Underline the importance of information, even scientific, in order to take appropriate choices. Build confidence in the effectiveness of the vaccination interventions against COVID 19 The project has been done by the students on the basis of multimedia digital tools, exploiting some IT tools like Google forms, PPTs, Spreadsheet, Excel. Students carried out an online survey addressed to a sample of the adult population among students' friends. Observational questionnaire asked the participants their sharing about some issues or the ticking of one or more options from a list of default answers. The survey involved a sample of people between 500 and 1000 units from April 15th to May 30th 2021.After the collection, all the data have been processed through tables and graphs according to the following macro-themes: Boundaries against vaccines Use of personal protective equipment The most feared pandemic risks and their environmental implications The outcome of the survey mainly highlights the population ‘attitude to get vaccine together with the awareness of the necessity of herd immunity achievement, to overcome this pandemic. Students stand point is that personal attitude toward prevention and personal behavior may have impact either on health or into environmental goals.

Three-dimensional genome organisation and replication timing are known to be correlated, however, it remains unknown whether nuclear architecture overall plays an instructive role in the replication-timing programme and, if so, how. Here we demonstrate that RIF1 is a molecular hub that co-regulates both processes. Both nuclear organisation and replication timing depend upon the interaction between RIF1 and PP1. However, whereas nuclear architecture requires the full complement of RIF1 and its interaction with PP1, replication timing is not sensitive to RIF1 dosage. The role of RIF1 in replication timing also extends beyond its interaction with PP1. Availing of this separation-of-function approach, we have therefore identified in RIF1 dual function the molecular bases of the co-dependency of the replication-timing programme and nuclear architecture., How nuclear architecture overall affects the replication-timing programme is not yet clear. Here the authors reveal RIF1’s dual role as a chromatin-interaction scaffold and regulator of replication timing that allows the coordination of these two aspects of nuclear function.

The light yield, the time resolution and the efficiency of different types of scintillating tiles with direct Silicon Photomultiplier readout and instrumented with a customised front-end electronics have been measured at the Beam Test Facility of Laboratori Nazionali di Frascati and several test stands. The results obtained with different configurations are presented. A time resolution of the order of 300 ps, a light yield of more than 230 photo-electrons, and an efficiency better than 99.8 $\%$ are obtained with $\sim 225$ cm$^2$ large area tiles. This technology is suitable for a wide range of applications in high-energy physics, in particular for large area muon and timing detectors., Comment: 28 pages, 24 figures, 6 tables

A two-dimensional numerical investigation on a prototypal solar chimney system integrated with an absorbing capacity wall in a south facade of a building is numerically studied. The capacity wall is composed of a high absorbing plate and an assigned thickness of phase change material. The chimney consists of a converging channel with one vertical absorbing wall and the glass plate inclined of 2°. The transient analysis on a two-dimensional model in airflow is carried out and the governing equations for natural convection in turbulent flow with Boussinesq assumption and thermophysical properties temperature independent are given in terms of k-ε turbulence model. The numerical analysis was intended to evaluate the thermal and fluid dynamic behavior of the solar chimney integrated with a latent thermal energy storage system for different values of the PCM thickness.

Summary DNA replication is temporally and spatially organized in all eukaryotes, yet the molecular control and biological function of the replication-timing program are unclear. Rif1 is required for normal genome-wide regulation of replication timing, but its molecular function is poorly understood. Here we show that in mouse embryonic stem cells, Rif1 coats late-replicating domains and, with Lamin B1, identifies most of the late-replicating genome. Rif1 is an essential determinant of replication timing of non-Lamin B1-bound late domains. We further demonstrate that Rif1 defines and restricts the interactions between replication-timing domains during the G1 phase, thereby revealing a function of Rif1 as organizer of nuclear architecture. Rif1 loss affects both number and replication-timing specificity of the interactions between replication-timing domains. In addition, during the S phase, Rif1 ensures that replication of interacting domains is temporally coordinated. In summary, our study identifies Rif1 as the molecular link between nuclear architecture and replication-timing establishment in mammals., Graphical Abstract, Highlights • Most late-replicating regions are marked by Rif1 (RADs) • Late replication in RADs is differentially regulated where Lamin B1 is stably bound • Rif1 constrains inter-domain contacts within the same replication timing in G1 • Rif1 coordinates the replication timing of interacting domains, At replication-timing establishment, chromatin domains are forced to interact only with regions sharing the same replication timing. Foti et al. demonstrate that Rif1 is responsible for this constraint because Rif1 deletion leads to loss of spatial limitations followed by replication-timing program disruption. Therefore, Rif1 links nuclear architecture and replication-timing establishment.

Some of the most important requirements for building performance are energy saving and recovering, ventilated roof and solar chimney are good systems for energy purposes. In winter period, a ventilated roof helps to contain heat losses, and in summer period, it helps reducing the solar heat gain and improving the indoor thermal comfort.Solar Chimney allows to have a ventilation system in building environment as well as to obtain electrical energy. It employs solar radiation to raise temperature of the air and the buoyancy of warm air to accelerate the air stream flowing through the system. By converting thermal energy into the kinetic energy of air movement. Solar chimneys have a number of different applications such as ventilation, passive solar heating and cooling of buildings, solar-energy drying, and power generation.

In Thermal Energy Systems the improvement of heat transfer is always a challenge for researcher. In particular, for storage and thermal management applications there are many improvement techniques to design and optimize the thermal energy systems, such as the addition of nanoparticles. The addition of nanoparticles in Heat Transfer Fluids (HTF) or in storage materials has lead to a new type of material called nanofluid if used for HTF or nano-PCM for storage applications. The main goal of the researchers is the characterization of the thermophysical properties of these new kind of materials.

In Thermal Energy Systems the improvement of heat transfer is always a challenge for researcher. In particular, for storage and thermal management applications there are many improvement techniques to design and optimize the thermal energy systems, such as the addition of metal foam, fins or using a honeycomb structure. In these areas, Thermal Energy Storage (TES) systems and heat exchangers are the most utilized devices. A TES works as a thermal buffer that store the exceed energy and release it when required, while the heat exchangers are a media to transfer thermal energy from solid to fluid and vice-versa.

Thermal energy needs determined by the increase demand is a fundamental and strategic energy source and it is very important to recover and store its lost and surplus. In this frame thermal energy storage (TES) is a natural solution and it becomes the necessary bridge between the energy demand and availability mainly in renewable energy sources due to their intermittent nature, particularly solar energy, which is the most prospective energy source. Moreover, the use of TES determines the improvement of performance and reliability of the energy systems [1]. There are three types of thermal energy storage systems (TESS): chemical energy storage system (CESS), sensible heat thermal energy storage system (SHTESS) and latent heat thermal energy storage system (LHTESS). The first system stores the heat through reversible chemical reactions, so when it receives heat the behavior of the chemical process is endothermic and when it releases heat the chemical process is exothermic [2]. The second system is based on increasing the temperature of the material that the system is made. The third system uses the phase change materials (PCMs) to store thermal energy at quasi-constant temperature. During the phase change process, the heat is used to change phase and not to increase the temperature [3]. The LHTESS is better because it presents many advantages like the low range of the working temperature and high energy density. Three types of PCMs are employed: solid-solid, solid-liquid and liquid-gas. The solid-solid phase change process allows to store the heat during the crystallization and the solid material is subject to a change in its crystal lattice. The main characteristics are: a low variation of volume during the phase change process and a low latent heat value. During the solid-liquid phase change process the material melts storing the heat and whereas in the opposite process, liquid-solid, it solidifies releasing of the heat. In the solid-liquid process the latent heat in general is higher than in the solid-solid transformation but the variation of volume is higher. The liquid-gas phase change process has the highest value of latent heat far from the critical point and a corresponding very high difference between the saturated vapor and liquid specific volumes. The solid-liquid phase change process is more suitable to store thermal energy because it represents the best compromise among these phase transformations. There is not a unique classification of the solid-liquid PCMs, but generally the main subdivision is organic and inorganic materials, as hydrated salts [4]. The principal organic material is the paraffin, it is widely used in the literature because it is stable, not corrosive, nontoxic and the phase change process is reversible [5]. These characteristics are not sufficient to design a LHTESS because the worse disadvantage is the small value of the thermal conductivity, leading to a long time for melting respect to a working cycle and a huge temperature gradient in the system. [1] Cabeza, L. F., Advances in Thermal Energy Storage Systems: Methods and Applications, Woodhead Publishing, Cambridge UK, 2014. [2] Gil A, Medrano M, Martorell I, Lazaro A, Dolado P, Zalba B, Cabeza LF, State of the art on high temperature thermal energy storage for power generation. Part 1 – Concepts, materials and modellization. Renewable and Sustainable Energy Reviews, 14, pp. 31-55, 2010. [3] Zhou, D., Zhao, C.Y.,Tian, Y., Review on thermal energy storage with phase change materials (PCMs) in building applications, Applied Energy, 92, pp. 593-605, 2012. [4] Khudhair AM, Mohammed MF (2004) A review on energy conservation in building applications with thermal storage by latent heat using phase change materials. Energy Convers Manag 45:263–275 [5] Abhat A (1983) Low temperature latent heat thermal energy storage: heat storage materials. Sol Energy 30:313–332

Lately TES systems for thermal applications, such as space and water heating, air-conditioning, cooling, etc. have received much attention. In TES system, energy is stored by changing the temperature of a storage medium or employing the latent heat of Phase Change Material (PCM). For a TES system, it is important to have a charging velocity rather high, because for an assigned system size, it is possible to obtain greater amount of stored energy in less time. Therefore, the heat transfer between the working fluid and the TES system should be improved by increasing the surface exchange area. In the present work a computational investigation on thermal energy storage system using Phase Change Material (PCM) is accomplished. The system is a set of different parallel plates, half of them are filled with PCM and in the others the working fluid, air, flows. Various configurations for different channels per unit of length (CPL) are investigated. A comparison between a direct model and a porous medium model is carried out. The porous medium is modeled with the Darcy-Forchheimer law. Numerical simulations are carried out using the Ansys-Fluent code for the direct model with 2n channels for direct and equivalent porous medium.

The Frascati National Laboratories (LNF) are the oldest and largest research infrastructure of INFN, mainly devoted to the research in nuclear and particle physics, to the development of particle accelerators and frontier studies on new acceleration techniques. LNF is the place where the first electron-positron collisions were obtained in the early 60s. Presently LNF operates two accelerator complexes: DAFNE, an e+e- collider with center of mass energy set to the mass of the Φ meson, 1020 MeV. SPARC, a high intensity photoinjector capable of delivering electron beams up to 200 MeV, combined with a high power laser (FLAME), able to produce ultra short pulses, in the so called SPARC_LAB facility. The laboratory hosts also the NAUTILUS gravitational waves resonant bar detector, and thanks to the availability of several infrastructures, workshops, clean rooms etc.., it is also widely used as a facility for constructing large particle detectors used in other laboratories. The purpose of the present document is to address the question: is there a viable program on the development of internal activities which can allow the Laboratory to maximally exploit its capabilities and to maintain its role at the forefront of scientific research in the next decade? In particular, given the present Italian financial situation, is this possible by wisely upgrading the presently running infrastructures at moderate costs? On November 10-11, 2014 a workshop was held at LNF with the aim to discuss the above issues, with a broad participation of researchers from Italian and foreign institutions. A second workshop dedicated to the applications of the existing facilities to Materials Science was held on February 26-27, 2015. This document tries to summarize the main conclusions of these discussions.

Natural and mixed convection in air in an inclined channel with the lower wall heated at uniform heat flux and in the presence of an obstacle either at the entrance or exit of the channel is investigated experimentally and numerically, respectively. The study is accomplished for several heat fluxes. In mixed convection the Reynolds number is equal to 150, this being in the laminar regime. Natural convection investigation is carried out with Rayleigh number equal to Ra=6.68x10 and 2.67x10. The effect of the obstacle disposition and height is investigated by flow visualization and wall temperature distribution.

The BTF (Beam-Test Facility) is a transfer line using the electron or positron beam of the DAΦNE LINAC. The particle beams can be attenuated, energy-selected and collimated for a wide range of energy and intensity. The beam parameters can be tuned to match the needs of each users, mainly in the field of HEP detector testing, but also dedicated studies of electromagnetic interaction. The BTF has been operational for more than 10 years, mainly in 'parasitic' mode to the operation of the DAΦNE collider, delivering beams for an average of more than 220 days/year. The potential of the BTF facility can be further enlarged following different lines of development, which are briefly discussed in this paper: improvement of the environmental shielding for high-intensity applications; extension of the beam bunch time-width; addition of new collimators to reduce beams divergence and background at low intensity; doubling of the beam extraction system and transport line; improvement of the tagged photon source; increase of the maximum energy from 750/550 MeV (for electrons/positrons) to about 1 GeV/750 MeV respectively; improvement of a neutron line using the photo-production target; improvement of the beam diagnostics, mainly based on particle detectors, and the develop of a new BTF sub-system controls.