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More than 50% of solar-mass stars form in multiple systems. It is therefore crucial to investigate how multiplicity affects the star and planet formation processes at the protostellar stage. We report continuum and C$^{18}$O (2-1) observations of the VLA 1623-2417 protostellar system at 50 au angular resolution as part of the ALMA Large Program FAUST. The 1.3 mm continuum probes the disks of VLA 1623A, B, and W, and the circumbinary disk of the A1+A2 binary. The C$^{18}$O emission reveals, for the first time, the gas in the disk-envelope of VLA 1623W. We estimate the dynamical mass of VLA 1623W, $M_{\rm dyn}=0.45\pm0.08$ M$_{\odot}$, and the mass of its disk, $M_{\rm disk}\sim6\times10^{-3}$ M$_{\odot}$. C$^{18}$O also reveals streamers that extend up to 1000 au, spatially and kinematically connecting the envelope and outflow cavities of the A1+A2+B system with the disk of VLA 1623W. The presence of the streamers, as well as the spatial ($\sim$1300 au) and velocity ($\sim$2.2 km/s) offset of VLA 1623W suggest that either sources W and A+B formed in different cores, interacting between them, or that source W has been ejected from the VLA 1623 multiple system during its formation. In the latter case, the streamers may funnel material from the envelope and cavities of VLA 1623AB onto VLA 1623W, thus concurring to set its final mass and chemical content., Comment: 10 pages, 5 figures, accepted by MNRAS

We have investigated the frontier orbitals of persistent organic radicals known as nitroxyls by resonant photoelectron spectroscopy (ResPES) under inner shell excitation. By means of this site-specific technique, we were able to disentangle the different atomic contributions to the outer valence molecular orbitals and examine several core-hole relaxation pathways involving the singly occupied molecular orbital (SOMO) localized on the nitroxyl group. To interpret the ResPES intensity trends, especially the strong enhancement of the SOMO ionized state at the N K-edge, we computed the Dyson spin orbitals (DSOs) pertaining to the transitions between the core-excited initial states and several of the singly ionized valence final states. We found that the computed vertical valence ionization potentials and norms of the DSOs are reasonably reliable when based on the long-range corrected CAM-B3LYP density functional. Thanks to their unpaired electrons, nitroxyls have recently found application in technological fields implying a spin control, such as spintronics and quantum computing. The present findings on the electronic structure of nitroxyl persistent radicals furnish important hints for their implementation in technological devices and, more in general, for the synthesis of new and stable organic radicals with tailored properties.

Context. Star-forming molecular clouds are characterised by the ubiquity of intertwined filaments. The filaments have been observed in both high- and low-mass star-forming regions, and they are thought to split into collections of sonic fibres. The locations where filaments converge are termed hubs, and these are associated with the young stellar clusters. However, the observations of filamentary structures within hubs at distances of 75–300 pc require a high angular resolution Aims. The integral shaped filament (ISF) of the Orion A molecular cloud is noted for harbouring several hubs within which no filamentary structures have been observed so far. The goal of our study is to investigate the nature of the filamentary structures within one of these hubs, which is the chemically rich hub OMC-2 FIR 4, and to analyse their emission with high density and shock tracers. Methods. We observed the OMC-2 FIR 4 proto-cluster using Band 6 of the Atacama Large (sub-)Millimetre Array (ALMA) in Cycle 4 with an angular resolution of ~0.26″ (100 au). We analysed the spatial distribution of dust, the shock tracer SiO, and dense gas tracers (i.e., CH3OH, CS, and H13CN). We also studied the gas kinematics using SiO and CH3OH maps. Results. Our observations for the first time reveal interwoven filamentary structures within OMC-2 FIR 4 that are probed by several tracers. Each filamentary structure is characterised by a distinct velocity as seen from the emission peak of CH3OH lines. They also show transonic and supersonic motions. SiO is associated with filaments and also with multiple bow-shock features. The bow-shock features have sizes between ~500 and 2700 au and are likely produced by the outflow from HOPS-370. Their dynamical ages are Conclusions. Our study unveiled the previously unresolved filamentary structures as well as the shocks within OMC-2 FIR 4. The kinematics of the filamentary structures might be altered by external and/or internal mechanisms such as the wind from H II regions, the precessing jet from the protostellar source HOPS-370, or the jet from VLA 15. While the complexity of the region, coupled with the limited number of molecular lines in our dataset, makes any clear association with these mechanisms challenging, our study shows that multi-scale observations of these regions are crucial for understanding the accretion processes and flow of material that shape star formation.

Context. Protostellar jets are an important agent of star formation feedback, tightly connected with the mass-accretion process. The history of jet formation and mass ejection provides constraints on the mass accretion history and on the nature of the driving source. Aims. We characterize the time-variability of the mass-ejection phenomena at work in the class 0 protostellar phase in order to better understand the dynamics of the outflowing gas and bring more constraints on the origin of the jet chemical composition and the mass accretion history. Methods. Using the NOrthern Extended Millimeter Array (NOEMA) interferometer, we have observed the emission of the CO 2–1 and SO NJ = 54–43 rotational transitions at an angular resolution of 1.0 00 (820 au) and 0.400 (330 au), respectively, toward the intermediate mass class 0 protostellar system Cep E. Results. The CO high-velocity jet emission reveals a central component of ≤400 au diameter associated with high-velocity molecular knots that is also detected in SO, surrounded by a collimated layer of entrained gas. The gas layer appears to be accelerated along the main axis over a length scale δ0 ∼ 700 au, while its diameter gradually increases up to several 1000 au at 2000 au from the protostar. The jet is fragmented into 18 knots of mass ∼10−3 M, unevenly distributed between the northern and southern lobes, with velocity variations up to 15 km s−1 close to the protostar. This is well below the jet terminal velocities in the northern (+65 km s−1) and southern (-125 km s-1)lobes. The knot interval distribution is approximately bimodal on a timescale of ∼50–80 yr, which is close to the jet driving protostar Cep E-A and ∼150−20 yr at larger distances >1200. The mass-loss rates derived from knot masses are steady overall, with values of 2.7 x 10−5 M yr−1 and 8.9 x 10−6 M yr−1 in the northern and southern lobe, respectively. Conclusions. The interaction of the ambient protostellar material with high-velocity knots drives the formation of a molecular layer around the jet. This accounts for the higher mass-loss rate in the northern lobe. The jet dynamics are well accounted for by a simple precession model with a period of 2000 yr and a mass-ejection period of 55 yr. © Authors 2022 741002; National Science Foundation, NSF: AST-2102405; Horizon 2020 Framework Programme, H2020; H2020 Marie Skłodowska-Curie Actions, MSCA: 811312; European Research Council, ERC; Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2020-0038; Centre National de la Recherche Scientifique, CNRS; Ural Federal University, UrFU interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). AS, BL, PR-RO, acknowledge support from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 811312 for the project “Astro-Chemical Origins” (ACO) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program for the Project “The Dawn of Organic Chemistry” (DOC) grant agreement No 741002. DSC is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-2102405. A.V. and A.P. are the members of the Max Planck Partner Group at the Ural Federal University. A.P. and A.V. acknowledge the support of the Russian Ministry of Science and Education via the State Assignment Contract no. FEUZ-2020-0038. Based on observations carried out with the IRAM NOEMA interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). AS, BL, PR-RO, acknowledge support from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 811312 for the project "Astro-Chemical Origins" (ACO) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program for the Project "The Dawn of Organic Chemistry" (DOC) grant agreement No 741002. DSC is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-2102405. A.V. and A.P. are the members of the Max Planck Partner Group at the Ural Federal University. A.P. and A.V. acknowledge the support of the Russian Ministry of Science and Education via the State Assignment Contract no. FEUZ-2020-0038.

(Abridged) We present a study of the disk population in L1688, the densest and youngest region in Ophiuchus, and we compare it with other nearby regions of different age, namely Lupus, Chamaeleon I, Corona Australis, Taurus and Upper Scorpius. We select our L1688 sample using a combination of criteria (ALMA data, Gaia, optical/near-IR spectroscopy) and determine stellar and disk properties, specifically stellar mass (Mstar), average population age, mass accretion rate (Macc) and disk dust mass (Mdust). a) In L1688 the relations between Macc and Mstar, Mdust and Mstar, and Macc and Mdust have a roughly linear trend with slopes 1.8-1.9 for the first two relations and ~1 for the third, similarly to what found in the other regions. b) When ordered according to the characteristic age of each region, Macc decreases as 1/t, when corrected for the different stellar mass content; Mdust follows roughly the same trend between 0.5 and 5 Myr, but has an increase of a factor ~3 at ages of 2-3 Myr. We suggest that this could result from an earlier planet formation, followed by collisional fragmentation that temporarily replenishes the millimeter-size grain population. c) The dispersion of Macc and Mdust around the best-fitting relation with Mstar, as well as that of Macc versus Mdust are large: we find that the dispersions have continuous distributions with a log-normal shape and similar width (~0.8 dex). The amount of dust observed at ~1 Myr does not appear to be sufficient to assemble the majority of planetary systems, which suggests an earlier planetary cores formation. The dust mass traces to a large extent the disk gas mass evolution. Two properties remain puzzling: the steep dependence of Macc and Mdust on Mstar and the cause of the large dispersion in the three relations analyzed in this paper, in particular the one of the Macc versus Mdust relation., A&A in press

Study question Could 448KHz electrostimulation be beneficial in the endometrial preparation for transfer in pre-menopausal or menopausal women? Summary answer Few women had adequate endometrium (8.3%) with standard treatments, which increased to 54.1% when combined with aspirin-sildenafyl, while when combined with 448KHz is over 75% What is known already We know that electrical stimulation is used in tissue engineering as a new regenerative medicine approach, which promotes cell proliferation and differentiation. In addition, it improves cell membrane permeability and cell metabolism. Study design, size, duration In the retrospective clinical study a total of 96 patients were considered, all in premenopausal or menopausal state, with inadequate endometrial response to common therapies and failure to transfer. In the following cycle, attempts were made to optimize the level of endometrial preparation by various approaches. Participants/materials, setting, methods The instrument used for electrostimulation was INDIBA. The 96 patients were divided into 4 groups: group A received estrogen therapy and 448KHz electrostimulation, group B received estrogen therapy, group C received estrogen therapy, aspirin and sildenafyl support, group D received estrogen therapy, aspirin-sildenafyl support and 448KHz electrostimulation. Main results and the role of chance Electrostimulation was found to be beneficial in group A (with electro-stimulation) where 75% of patients had an endometrium suitable for transfer compared to group B (without electro-stimulation) with only 8.3%. Similarly, group C (without electro-stimulation) had 54.1% of patients with a suitable endometrium, while group D (with electro-stimulation) had 87.5%. Limitations, reasons for caution The limitations are related to the nature of the study, which is retrospective, so although the starting conditions were evaluated to reduce bias, we suggest confirmation with a prospective randomized clinical trial to validate these data, which will be our next objective. Wider implications of the findings The common therapeutic approach of endometrial preparation, when combined with electrostimulation, leads to a drastic decrease in cancelled cycles due to an inadequate endometrium. Trial registration number not applicable

C. Codella et al., The ALMA (Atacama Large Millimeter Array) interferometer, with its unprecedented combination of high sensitivity and high angular resolution, allows for (sub-)mm wavelength mapping of protostellar systems at Solar system scales. Astrochemistry has benefitted from imaging interstellar complex organic molecules in these jet–disc systems. Here, we report the first detection of methanol (CH3OH) and methyl formate (HCOOCH3) emission towards the triple protostellar system VLA1623−2417 A1+A2+B, obtained in the context of the ALMA Large Programme FAUST (Fifty AU STudy of the chemistry in the disc/envelope system of solar-like protostars). Compact methanol emission is detected in lines from Eu = 45 K up to 61 K and 537 K towards components A1 and B, respectively. Large velocity gradient analysis of the CH3OH lines towards VLA1623−2417 B indicates a size of 0.11–0.34 arcsec (14–45 au), a column density NCH3OH = 1016–1017 cm−2, kinetic temperature ≥ 170 K, and volume density ≥ 108 cm−3. A local thermodynamic equilibrium approach is used for VLA1623−2417 A1, given the limited Eu range, and yields Trot ≤ 135 K. The methanol emission around both VLA1623−2417 A1 and B shows velocity gradients along the main axis of each disc. Although the axial geometry of the two discs is similar, the observed velocity gradients are reversed. The CH3OH spectra from B show two broad (4–5 km s−1) peaks, which are red- and blueshifted by ∼ 6–7 km s−1 from the systemic velocity. Assuming a chemically enriched ring within the accretion disc, close to the centrifugal barrier, its radius is calculated to be 33 au. The methanol spectra towards A1 are somewhat narrower (∼ 4 km s−1), implying a radius of 12–24 au., This project has received funding from: (1) the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme, for the Project ‘The Dawn of Organic Chemistry’ (DOC), grant agreement no. 741002; (2) the PRIN-INAF 2016 The Cradle of Life – GENESIS-SKA (General Conditions in Early Planetary Systems for the rise of life with SKA); (3) a Grant-in-Aid from Japan Society for the Promotion of Sci- ence (KAKENHI: Nos. 18H05222, 20H05844, 20H05845); (4) the Spanish FEDER under project number ESP2017-86582-C4-1-R; (5) DGAPA, UNAM grants IN112417 and IN112820, and CONACyT, Mexico; (6) ANR of France under contract number ANR-16-CE31- 0013; (7) the French National Research Agency in the framework of the Investissements d’Avenir programme (ANR-15-IDEX-02), through the funding of the ‘Origin of Life’ project of the Univ. Grenoble-Alpes, (8) the European Union’s Horizon 2020 research and innovation programmes under projects ‘Astro-Chemistry Ori- gins’ (ACO), Grant No. 811312; (9) the National Research Council Canada and an NSERC Dico v ery Grant to DJ. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2018.1.01205.L. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Obser- vatory is operated by ESO, A UI/NRA O, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Early identification of those with BRCA-related Hereditary Breast and Ovarian Cancer Syndrome (HBOC) and Lynch syndrome has the potential for early cancer detection and/or prevention; as such, these conditions are considered Tier 1 genetic conditions by the U.S. Center for Disease Control and Prevention. Given the decreasing cost of genetic testing, population-based screening (PBS) for such conditions may be the next step toward cancer prevention. This study aimed to understand genetic counselors' perspectives toward offering PBS for the Tier 1 conditions BRCA-related HBOC and Lynch syndrome. An online survey was distributed to 3,609 members of the National Society of Genetic Counselors. A total of 367 individuals participated in the study. Fifty percent of respondents felt that PBS for inherited cancer should not be offered; 93.3% felt that the current healthcare system is unprepared for implementation of PBS. However, most respondents agreed that PBS should be implemented within the next 10 years. Attitudes toward offering PBS were associated with respondents' work setting, cancer specialization, and perceived preparedness (p's

We report on the C K-edge x-ray absorption spectra and the resonant (RXES) and non-resonant (NXES) x-ray emission spectra of ethylene, allene and butadiene in the gas phase. The RXES and NXES show clear differences for the different molecules. Overall both types of spectra are more structured for ethylene and allene, than for butadiene. Using density functional theory–restricted open shell configuration interaction single calculations, we simulate the spectra with remarkable agreement with the experiment. We identify the spectral features as being due to transitions involving localised 1s orbitals. For allene, there are distinct spectral bands that reflect transitions predominantly from either the central or terminal carbon atoms. These results are discussed in the context of ultrafast x-ray studies aimed at detecting the passage through conical intersections in polyatomic molecules.

C. Vastel et al., [Aims] Methanol is a ubiquitous species commonly found in the molecular interstellar medium. It is also a crucial seed species for the build-up of chemical complexity in star forming regions. Thus, understanding how its abundance evolves during the star formation process and whether it enriches the emerging planetary system is of paramount importance., [Methods] We used new data from the ALMA Large Program FAUST (Fifty AU STudy of the chemistry in the disc/envelope system of solar protostars) to study the methanol line emission towards the [BHB2007] 11 protobinary system (sources A and B), where a complex structure of filaments connecting the two sources with a larger circumbinary disc has previously been detected., [Results] Twelve methanol lines have been detected with upper energies in the [45–537] K range along with one 13CH3OH transition and one methyl formate (CH3OCHO) line blended with one of the methanol transitions. The methanol emission is compact (FWHM ~ 0.5″) and encompasses both protostars, which are separated by only 0.2″ (28 au). In addition, the overall methanol line emission presents three velocity components, which are not spatially resolved by our observations. Nonetheless, a detailed analysis of the spatial origin of these three components suggests that they are associated with three different spatial regions, with two of them close to 11B and the third one associated with 11A. A radiative transfer analysis of the methanol lines gives a kinetic temperature of [100–140] K, an H2 volume density of 106–107 cm−3 and column density of a few 1018 cm−2 in all three components with a source size of ~0.15″. Thus, this hot and dense gas is highly enriched in methanol with an abundance as high as 10−5. Using previous continuum data, we show that dust opacity can potentially completely absorb the methanol line emission from the two binary objects., [Conclusions] Although we cannot firmly exclude other possibilities, we suggest that the detected hot methanol is resulting from the shocked gas from the incoming filaments streaming towards [BHB2007] 11A and B, respectively. Higher spatial resolution observations are necessary to confirm this hypothesis., This project has received funding within the European Union’s Horizon 2020 research and innovation program from the European Research Council (ERC) for the project The Dawn of Organic Chemistry (DOC), grant agreement no. 741002, and from the Marie Sklodowska-Curie for the project Astro-Chemical Origins (ACO), grant agreement no. 811312. I.J.-S. has received partial support from the Spanish State Research Agency (project number PID2019-105552RB-C41). D.J. is supported by NRC Canada and by an NSERC Discovery Grant. S.Y. thanks the support by Grant-in-Aids from Ministry of Education, Culture, Sports, Science, and Technologies of Japan (18H05222). This paper makes use of the following ALMA data: ADS/JAO.ALMA#2018.1.01205.L. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

The starburst pi-conjugated molecule 4,4 ',4 ''-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine (C57H48N4, m-MTDATA), based on triphenylamine (TPA) building blocks, is widely used in optoelectronic devices due to its good electron-donor characteristics. The electronic structure of m-MTDATA was investigated for the first time in the gas phase by means of PhotoElectron Spectroscopy (PES) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. The combination of Density Functional Theory (DFT) calculations with the experimental spectra provides a comprehensive description of the molecular electronic structure. Moreover, by comparing the results with previous TPA measurements, we could shed light on how the electronic structure evolves when the molecular size is increased. We found that the C 1s photoelectron spectra of m-MTDATA and TPA are similar, due to the balance of the counter-acting effects of the electronegativity of the N atoms and the delocalization of the amine lone-pair electrons. In contrast, the increased number of N atoms (i.e. N lone pairs) in m-MTDATA determines a three-peak feature in the outermost valence binding energy region with strong contributions by the N 2p(z) orbitals. We also obtained a decrease of the HOMO-LUMO gap for m-MTDATA, which points to improved electron donating properties of m-MTDATA with respect to TPA.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome virus 2 (SARS-CoV-2), has led to a global crisis that included collapsing healthcare systems and shut-down communities, producing considerable economic burden. Despite the number of effective vaccines quickly implemented, the emergence of new variants is a primary concern. The scientific community undertook a rapid response to better study this new virus. However, critical questions about viral protein-protein interactions and mechanisms of its physiopathology are still unclear. Although severe COVID-19 was associated with hematological dysfunctions, scarce experimental data were produced about iron dysmetabolism and the viral proteins’ possible interaction with hemoglobin (Hb) chains. This work demonstrates the binding of SARS-CoV-2 proteins to hemin and Hb using a multimethodological approach. In silico analysis indicated binding motifs between a cavity in the viral nucleoprotein and hemoglobin’s porphyrin coordination region. Different hemin binding capacities of mock and SARS-CoV-2-infected culture extracts were noticed using gel electrophoresis and TMB staining. Hemin-binding proteins were isolated from SARS-CoV-2-infected cells by affinity chromatography and identified by shotgun proteomics, indicating that structural (nucleoprotein, spike, and membrane protein) and non-structural (Nsp3 and Nsp7) viral proteins interact with hemin. In vitro analyses of virus adsorption to host cells and viral replication studies in Vero cells demonstrated inhibitory activities - at different levels - by hemin, protoporphyrin IX (PpIX) Hb. Strikingly, free Hb at 1μM suppressed viral replication (99 %), and its interaction with SARS-CoV-2 was localized to the RBD region of the Spike protein. The findings showed clear evidence of new avenues to disrupt viral replication and understand virus physiopathology that warrants further investigation.

MECP2 mutations cause Rett syndrome (RTT), a severe and progressive neurodevelopmental disorder mainly affecting females. Although RTT patients exhibit delayed onset of symptoms, several evidences demonstrate that MeCP2 deficiency alters early development of the brain. Indeed, during early maturation, Mecp2 null cortical neurons display widespread transcriptional changes, reduced activity, and defective morphology. It has been proposed that during brain development these elements are linked in a feed‐forward cycle where neuronal activity drives transcriptional and morphological changes that further increase network maturity. We hypothesized that the enhancement of neuronal activity during early maturation might prevent the onset of RTT‐typical molecular and cellular phenotypes. Accordingly, we show that the enhancement of excitability, obtained by adding to neuronal cultures Ampakine CX546, rescues transcription of several genes, neuronal morphology, and responsiveness to stimuli. Greater effects are achieved in response to earlier treatments. In vivo, short and early administration of CX546 to Mecp2 null mice prolongs lifespan, delays the disease progression, and rescues motor abilities and spatial memory, thus confirming the value for RTT of an early restoration of neuronal activity., Neuronal activity drives transcriptional and morphological changes that ensure maturation. Such mechanism is affected by Mecp2 absence. We show the rescue effects produced by enhancing Mecp2 null neurons activity and propose new therapeutic time windows for the treatment of Rett syndrome.

Bianchi, E. et al., The study of hot corinos in solar-like protostars has been so far mostly limited to the Class 0 phase, hampering our understanding of their origin and evolution. In addition, recent evidence suggests that planet formation starts already during Class I phase, which therefore represents a crucial step in the future planetary system chemical composition. Hence, the study of hot corinos in Class I protostars has become of paramount importance. Here, we report the discovery of a hot corino towards the prototypical Class I protostar L1551 IRS5, obtained within the ALMA (Atacama Large Millimeter/submillimeter Array) Large Program FAUST (Fifty AU STudy of the chemistry in the disc/envelope system of solar-like protostars).We detected several lines from methanol and its isotopologues (13CH3OH and CH2DOH), methyl formate, and ethanol. Lines are bright towards the north component of the IRS5 binary system, and a possible second hot corino may be associated with the south component. The methanol lines' non-LTE analysis constrains the gas temperature (100 K), density (1.5 × 108 cm3), and emitting size (10 au in radius). All CH3OH and 13CH3OH lines are optically thick, preventing a reliable measure of the deuteration. The methyl formate and ethanol relative abundances are compatible with those measured in Class 0 hot corinos. Thus, based on this work, little chemical evolution from Class 0 to I hot corinos occurs., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

The near-edge X-ray absorption fine structure (NEXAFS and X-ray photoelectron (XP) spectra of gas-phase 2,8-bis-(diphenylphosphoryl)dibenzo[b,d]thiophene (PPT) and triphenylphosphine oxide (TPPO) have been measured at the S and P L-II,L-III-edge regions. The time-dependent density functional theory (TDDFT) based on the relativistic two-component zeroth-order regular approximation approach has been used to provide an assignment of the experimental spectra, giving the contribution of the spin-orbit splitting and of the molecular-field splitting to the sulfur and phosphor binding energies. Computed XP and NEXAFS spectra agree well with the experimental measurements. In going from dibenzothiophene and TPPO to PPT, the nature of the most intense S 2p and P 2p NEXAFS features are preserved; this trend suggests that the electronic and geometric behaviors of the S and P atoms in the two building block moieties are conserved in the more complex system of PPT. This work enables us to shed some light onto the structure of the P-O bond, a still highly debated topic in the chemical literature. Since the S 2p and P 2p NEXAFS intensities provide specific information on the higher-lying localized sigma*(C-S) and sigma*(P-O) virtual MOs, we have concluded that P 3d AOs are not involved in the formation of the P-O bond. Moreover, the results support the mechanism of negative hyperconjugation, by showing that transitions toward sigma*(P-O) states occur at lower energies with respect to those toward it pi*(P-O) states.

The peripheral arteries and veins of the extremities are among the most commonly injured vessels in both civilian and military vascular trauma. Blunt causes are more frequent than penetrating except during military conflicts and in certain geographic areas. Physical examination and simple bedside investigations of pulse pressures are key in early identification of these injuries. In stable patients with equivocal physical examinations, computed tomography angiograms have become the mainstay of screening and diagnosis. Immediate open surgical repair remains the first-line therapy in most patients. However, advances in endovascular therapies and more widespread availability of this technology have resulted in an increase in the range of injuries and frequency of utilization of minimally invasive treatments for vascular injuries in stable patients. Prevention of and early detection and treatment of compartment syndrome remain essential in the recovery of patients with significant peripheral vascular injuries. The decision to perform amputation in patients with mangled extremities remains difficult with few clear indicators. The American Association for the Surgery of Trauma in conjunction with the World Society of Emergency Surgery seeks to summarize the literature to date and provide guidelines on the presentation, diagnosis, and treatment of peripheral vascular injuries. LEVEL OF EVIDENCE Review study, level IV. © Wolters Kluwer Health, Inc. All rights reserved.

© 2020, The Author(s). Individuals with Angelman syndrome (AS) are characterized by severe cognitive impairments alongside an enhanced drive for social engagement. As knowledge on imitation skills in this population is limited, we conducted the first controlled study of imitation in AS. We examined how 23 individuals with AS and 21 typically developing young children with similar mental age imitated novel actions in response to socially or non-socially engaging models, and in response to video-recorded versus live demonstrations of novel actions. Individuals with AS imitated as frequently and as accurately as typical young children in response to live demonstrations; but they imitated less frequently and less accurately in response to video-recorded demonstrations. Further, imitation was modulated by whether the demonstrator was socially engaging or emotionally neutral in the AS group, while this modulation was not present in the comparison group. Individuals with higher mental age imitated more frequently and more accurately across groups. Imitation performance in AS appears to be more modulated by the social context compared to typical infants and young children with similar mental age, possibly reflecting an enhanced drive for social engagement. A socially engaging instructional style might facilitate imitative learning in this population.

Abdominal vascular trauma accounts for a small percentage of military and a moderate percentage of civilian trauma, affecting all age ranges and impacting young adult men most frequently. Penetrating causes are more frequent than blunt in adults, while blunt mechanisms are more common among pediatric populations. High rates of associated injuries, bleeding, and hemorrhagic shock ensure that, despite advances in both diagnostic and therapeutic technologies, immediate open surgical repair remains the mainstay of treatment for traumatic abdominal vascular injuries. Because of their devastating nature, abdominal vascular injuries remain a significant source of morbidity and mortality among trauma patients. The American Association for the Surgery of Trauma in conjunction with the World Society of Emergency Surgery seek to summarize the literature to date and provide guidelines on the presentation, diagnosis, and treatment of abdominal vascular injuries. LEVEL OF EVIDENCE Review study, level IV. © Wolters Kluwer Health, Inc. All rights reserved.

Aim: In the past, observations of protostellar shocks have been able to set constraints on the formation route of formamide (NH2CHO), exploiting its observed spatial distribution and comparison with astrochemical model predictions. In this work, we follow the same strategy to study the case of acetaldehyde (CH3CHO). Method: To this end, we used the data obtained with the IRAM-NOEMA interferometer in the framework of the Large Program SOLIS to image the B0 and B1 shocks along the L1157 blueshifted outflow in methanol (CH3OH) and acetaldehyde line emission. Results: We imaged six CH3OH and eight CH3CHO lines which cover upper level energies up to 30 K. Both species trace the B0 molecular cavity as well as the northern B1 portion, i.e. the regions where the youngest shocks (1000 yr) occurred. The CH$_3$OH and CH$_3$CHO emission peaks towards the B1b clump, where we measured the following column densities and relative abundances: 1.3 x 10^16 cm-2 and 6.5 x 10-6 (methanol), and 7 x 10^13 cm-2 and 3.5 x 10-8 (acetaldehyde). We carried out a non-LTE LVG analysis of the observed CH3OH line: the average kinetic temperature and density of the emitting gas are Tkin = 90 K and nH2 = 4 x 10^5 cm-3, respectively. The CH3OH and CH3CHO abundance ratio towards B1b is 190, varying by less than a factor 3 throughout the whole B0-B1 structure. Conclusions: The comparison of astrochemical model predictions with the observed methanol and acetaldehyde spatial distribution does not allow to distinguish whether acetaldehyde is formed on the grain mantles or rather on the gas-phase, as its gas-phase formation, dominated by the reaction of ethyl radical (CH3CH2) with atomic oxygen, is very fast. Observations of acetaldehyde in younger shocks, e.g. 10^2 yr old, or/and of the ethyl radical, whose frequencies are not presently available, are necessary to settle the issue., A&A, in press

Aims: A unique environment to study how interstellar Complex Organic Molecules (iCOMs) can be formed is the shocked gas along low-mass protostellar outflows, as the dust mantles composition is sputtered into the gas phase. The chemical richness in these environments has been so far studied only in the L1157 blue shifted outflow. Methods: To understand if the L1157-B1 case is unique, we imaged the NGC 1333 IRAS 4A outflows using the NOEMA (NOrthern Extended Millimeter Array) interferometer as part of the IRAM SOLIS (Seeds Of Life in Space) Large Program and compared the observations with the GRAINOBLE+ gas phase astrochemical model. Results: Several iCOMs were detected in the IRAS 4A outflows: methanol (CH$_3$OH), acetaldehyde (CH$_3$CHO), formamide (NH$_2$CHO) and dimethyl ether (CH$_3$OCH$_3$), all sampling upper excitation energy up to $\sim$30 K. We found a significant chemical differentiation between the IRAS 4A1 outflow, showing a richer molecular content, and the IRAS 4A2 one. The CH$_3$OH/CH$_3$CHO abundance ratio is lower by a factor $\sim$4 in the former; furthermore the ratio in both outflows is lower by a factor $\sim$10 with respect to hot corinos values. Conclusions: After L1157-B1, IRAS 4A outflow is now the second outflow to show an evident chemical complexity. Given that CH$_3$OH is a grain surface species, GRAINOBLE+ reproduced our observations assuming acetaldehyde formation in gas phase by the reaction of ethyl radical (CH$_3$CH$_2$) with atomic oxygen. Moreover, the chemical differentiation between the two outflows suggests that the IRAS 4A1 outflow is likely younger than the IRAS 4A2 one. Further investigation is needed to constrain the age of the outflow and observations of even younger shocks are necessary and future spectroscopic studies on CH$_3$CH$_2$ are needed to be able to observe this species and provide strong constraints on the CH$_3$CHO formation., Comment: 12 pages, 7 figures, 5 tables

Context. Low-mass protostars drive powerful molecular outflows that can be observed with millimetre and submillimetre telescopes. Various sulfuretted species are known to be bright in shocks and could be used to infer the physical and chemical conditions throughout the observed outflows. Aims. The evolution of sulfur chemistry is studied along the outflows driven by the NGC 1333-IRAS4A protobinary system located in the Perseus cloud to constrain the physical and chemical processes at work in shocks. Methods. We observed various transitions from OCS, CS, SO, and SO2 towards NGC 1333-IRAS4A in the 1.3, 2, and 3 mm bands using the IRAM NOrthern Extended Millimeter Array and we interpreted the observations through the use of the Paris-Durham shock model. Results. The targeted species clearly show different spatial emission along the two outflows driven by IRAS4A. OCS is brighter on small and large scales along the south outflow driven by IRAS4A1, whereas SO2 is detected rather along the outflow driven by IRAS4A2 that is extended along the north east-south west direction. SO is detected at extremely high radial velocity up to + 25 km s-1 relative to the source velocity, clearly allowing us to distinguish the two outflows on small scales. Column density ratio maps estimated from a rotational diagram analysis allowed us to confirm a clear gradient of the OCS/SO2 column density ratio between the IRAS4A1 and IRAS4A2 outflows. Analysis assuming non Local Thermodynamic Equilibrium of four SO2 transitions towards several SiO emission peaks suggests that the observed gas should be associated with densities higher than 105 cm-3 and relatively warm (T > 100 K) temperatures in most cases. Conclusions. The observed chemical differentiation between the two outflows of the IRAS4A system could be explained by a different chemical history. The outflow driven by IRAS4A1 is likely younger and more enriched in species initially formed in interstellar ices, such as OCS, and recently sputtered into the shock gas. In contrast, the longer and likely older outflow triggered by IRAS4A2 is more enriched in species that have a gas phase origin, such as SO2., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

After a well-known actor was treated at a Chicago, Illinois, hospital, word spread through the media that many hospital employees were reportedly terminated for improper or unauthorized access in viewing his medical record. In high-profile hospital stays, healthcare workers may be tempted to open a celebrity patient's medical record; however, the consequences of such unauthorized access may be grave and involve more than the loss of employment. This article reviews the Health Insurance Portability and Accountability Act of 1996 (HIPAA) regulations, how violations are addressed, and the role of regulators in preventing and addressing such breaches.

The relationship between young stellar clusters and respective parental molecular clouds is still an open issue: for instance, are the similarities between substructures of clouds and clusters just a coincidence? Or would they be the indication of a physical relationship? In order to address these issues, we have studied the CMa OB1/R1 region that shows evidence for a complex star formation history. We obtained molecular clouds mapping with the IRAM-30 metre telescope to reveal the physical conditions of an unexplored side of the CMa region aiming to compare the morphology of the clouds with the distribution of the young stellar objects (YSOs). We also study the clouds kinematics searching for gradients and jet signatures that could trace different star formation scenarios. The YSOs were selected on the basis of astrometric data from Gaia EDR3 that characterise the moving groups. The distance of 1099$_{-24}^{+25}$ pc was obtained for the sample, based on the mean error-weighted parallax. Optical and near-infrared photometry is used to verify the evolutionary status and circumstellar characteristics of the YSOs. Among the selected candidates we found 40 members associated with the cloud: 1 Class I, 11 Class II, and 28 Class III objects. Comparing the spatial distribution of the stellar population with the cores revealed by the 13CO map, we verify that peaks of emission coincide with the position of YSOs confirming the association of these objects to their dense natal gas. Our observations support the large-scale scenario of the CMa shell-like structure formed as a relic of successive supernova events., A&A (accepted): 11 pages with 8 figures and 4 Tables

We present the first census of the interstellar Complex Organic Molecules (iCOMs) in the low-mass Class I protostar SVS13-A, obtained by analysing data from the IRAM-30m Large Project ASAI (Astrochemical Surveys At IRAM). They consist of an high-sensitivity unbiased spectral survey at the 1mm, 2mm and 3mm IRAM bands. We detected five iCOMs: acetaldehyde (CH$_3$CHO), methyl formate (HCOOCH$_3$), dimethyl ether (CH$_3$OCH$_3$), ethanol (CH$_3$CH$_2$OH) and formamide (NH$_2$CHO). In addition we searched for other iCOMs and ketene (H$_2$CCO), formic acid (HCOOH) and methoxy (CH$_3$O), whose only ketene was detected. The numerous detected lines, from 5 to 37 depending on the species, cover a large upper level energy range, between 15 and 254 K. This allowed us to carry out a rotational diagram analysis and derive rotational temperatures between 35 and 110 K, and column densities between $3\times 10^{15}$ and $1\times 10^{17}$ cm$^{-2}$ on the 0."3 size previously determined by interferometric observations of glycolaldehyde. These new observations clearly demonstrate the presence of a rich chemistry in the hot corino towards SVS13-A. The measured iCOMs abundances were compared to other Class 0 and I hot corinos, as well as comets, previously published in the literature. We find evidence that (i) SVS13-A is as chemically rich as younger Class 0 protostars, and (ii) the iCOMs relative abundances do not substantially evolve during the protostellar phase., Comment: 24 pages, MNRAS in press

The chemical composition of protostellar jets and its origin are still badly understood. More observational constraints are needed to make progress. With that objective, we have carried out a systematic search for molecular species in the jet of Cep E-mm, a template for intermediate-mass Class 0 protostars, associated with a luminous, high-velocity outflow. We made use of an unbiased spectral line survey in the range 72-350 GHz obtained with the IRAM 30m telescope, complementary observations of the CO $J$=3-2 transition with the JCMT, and observations at 1" angular resolution of the CO $J$=2-1 transition with the IRAM Plateau de Bure interferometer. In addition to CO, we have detected rotational transitions from SiO, SO, H$_2$CO, CS, HCO$^{+}$ and HCN. A strong chemical differentiation is observed in the southern and northern lobes of the jet. Radiative transfer analysis in the Large Velocity Gradient approximation yields typical molecular abundances of the order of $10^{-8}$ for all molecular species other than CO. Overall, the jets exhibit an unusual chemical composition, as CS, SO and H$_2$CO are found to be the most abundant species, with a typical abundance of (3-4)$\times 10^{-8}$. The transverse size of the CO jet emission estimated from interferometric observations is about 1000 au, suggesting that we are detecting emission from a turbulent layer of gas entrained by the jet in its propagation and not the jet itself. We propose that some molecular species could be the signatures of the specific photochemistry driven by the UV radiation field generated in the turbulent envelope., 14 pages, 11 figures, accepted to publication on MNRAS

Aim Peritoneal carcinomatosis is a common evolution of neoplasms and the terminal stage of disease. A new therapeutic technique, based on the total surgical removal of peritoneal lesions (peritonectomy procedure – PP) combined with the intraperitoneal chemohyperthermia (IPCH), has been developed. Proper patient selection is mandatory for optimizing the results of treatment. The aim of this study was to investigate the role of [(18)F]fluoro-2-deoxy- d -glucose Positron Emission Tomography/Computed Tomography ( 18 F-FDG PET/CT) in patients with peritoneal carcinosis selected to undergo PP and IPCH. Furthermore, we aimed to identify characteristic patterns of abdominal 18 F-FDG uptake and to correlate these patterns with available anatomic findings after surgery. Methods Patients with either histologically confirmed peritoneal carcinosis or suspected upon clinical follow-up and/or imaging findings were prospectively submitted to pre-surgery 18 F-FDG PET/CT scan. Only those patients without evidence of extra-peritoneal metastases at PET/CT scan were treated with PP and IPCH. Results 11 patients with peritoneal carcinomatosis (5 colorectal, 4 ovarian, 1 pancreatic) and 1 unknown primitive cancer, were eligible for the study. In all cases PET/CT scan showed multiple peritoneal implants. In 6 out of 11 cases (54%) metastases were evidenced by 18 F-FDG PET/CT: 2 cases with liver metastases; 1 case with bone metastases; 3 patients with lymph-node lesions. Two distinct imaging patterns, with focal or diffuse increased 18 F-FDG uptake, were recognized. Conclusions PP + IPCH of patients selected by 18 F-FDG PET/CT seems to be safe and feasible. PET/CT scan appears as a reliable tool for the detection, characterization of peritoneal implants with potential impact in the therapeutic management of these patients.

The near-edge x-ray-absorption fine-structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) spectra of benzo[b]thiophene (BBT) and dibenzothiophene (DBT) in the gas phase have been measured at the carbon Kedge and sulfur L-II,L-III-edge regions. The assignment of the spectral features has been provided by theoretical calculations based on density functional theory (DFT) and its time-dependent generalization (TDDFT) in the linear response regime. Observed trends in computed C 1s and S 2p ionization potentials (IPs) have been rationalized in terms of both the inductive effects due to the presence of S and the increased pi-electrons delocalization arising from the benzoannulation process. The analysis of the NEXAFS carbon K-edge and sulfur L-II,L-III-edge regions regions provided information on both low-lying delocalized virtual pi orbitals, and higher-lying localized sigma*(C-S) states. The evolution of the NEXAFS carbon K-edge spectral features along the series thiophene (T) and derivatives, BBT and DBT, is informative of a stabilizing effect due to increased aromaticity. This effect is however more pronounced in going from T to BBT compared to the introduction of a second annulated phenyl ring in DBT. The nature of the most intense sulfur L-II,L-III-edge NEXAFS spectral features is instead conserved along the series reflecting thus the localized nature of the virtual states involved in the S 2p core-excitation process.

Background Peritoneal metastasis from biliary carcinoma (PMC) is associated with poor prognosis when treated with chemotherapy. Objective To evaluate the impact on survival of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), and compare with conventional palliative chemotherapy for patients with PMC. Material and methods A prospective multicenter international database was retrospectively searched to identify all patients with PMC treated with a potentially curative CRS/HIPEC (CRS/HIPEC group). The overall survival (OS) was compared to patients with PMC treated with palliative chemotherapy (systemic chemotherapy group). Survival was analyzed using Kaplan-Meier method and compared with Log-Rank test. Results Between 1995 and 2015, 34 patients were included in the surgical group, and compared to 21 in the systemic chemotherapy group. In the surgical group, median peritoneal cancer index was 9 (range 3–26), macroscopically complete resection was obtained for 25 patients (73%). There was more gallbladder localization in the surgical group compared to the chemotherapy group (35% vs. 18%, p = 0.001). Median OS was 21.4 and 9.3 months for surgical and chemotherapy group, respectively (p=0.007). Three-year overall survival was 30% and 10% for surgical and chemotherapy group, respectively. Conclusion Treatment with CRS and HIPEC for biliary carcinoma with peritoneal metastasis is feasible and may provide survival benefit when compared to palliative chemotherapy.

Introduction Peritoneal metastasis (PM) of hepatocellular carcinoma (HCC) without distant spread are rare. The related prognosis is poor without standard treatment available. The role of cytoreduction surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is poorly documented. Methods An international multicentric cohort was constituted by retrospective analysis of 21 patients undergoing CRS/HIPEC for PM of HCC between 1992 and 2016 from 10 reference centers of PSOGI. Data on clinical features, treatment strategies, and survival outcomes were analyzed. Results The median time interval from the diagnosis of PM to the procedure was 4.5 months. The median peritoneal cancer index was 14. Sixteen patients had complete cytoreduction (CCR0-1). Ten patients had grades 3 to 4 complications. The median duration of follow-up was 52.2 months. The median OS was 46.7 months. The projected 3y-OS and 5y-OS were 88.9 and 49.4% respectively. The median OS for patients with CCR0-1 resection was not reached whereas it was 5.9 months for those with CCR2-3 resection after CRS (p = 0.0005). The median RFS was 26.3 months and projected RFS at 3 years of 36.5 months Three prognostic factors were associated with improved RFS in the univariate analysis: preoperative chemotherapy (p = 0.0156), PCI >15 (p = 0.009), Number of chemotherapy agents used for HIPEC (p = 0.005). Conclusion CRS/HIPEC is a safe and effective approach in selected patients with PM of HCC. CRS/HIPEC gives the patient a chance for a good relapse free and overall survival and should be considered as an option.

Although chemical models predict that the deuterium fractionation in N$_2$H$^+$ is a good evolutionary tracer in the star formation process, the fractionation of nitrogen is still a poorly understood process. Recent models have questioned the similar evolutionary trend expected for the two fractionation mechanisms in N$_2$H$^+$, based on a classical scenario in which ion-neutral reactions occurring in cold gas should have caused an enhancement of the abundance of N$_2$D$^+$, $^{15}$NNH$^+$, and N$^{15}$NH$^+$. In the framework of the ASAI IRAM-30m large program, we have investigated the fractionation of deuterium and $^{15}$N in N$_2$H$^+$ in the best known representatives of the different evolutionary stages of the Sun-like star formation process. The goal is to ultimately confirm (or deny) the classical "ion-neutral reactions" scenario that predicts a similar trend for D and $^{15}$N fractionation. We do not find any evolutionary trend of the $^{14}$N/$^{15}$N ratio from both the $^{15}$NNH$^+$ and N$^{15}$NH$^+$ isotopologues. Therefore, our findings confirm that, during the formation of a Sun-like star, the core evolution is irrelevant in the fractionation of $^{15}$N. The independence of the $^{14}$N/$^{15}$N ratio with time, found also in high-mass star-forming cores, indicates that the enrichment in $^{15}$N revealed in comets and protoplanetary disks is unlikely to happen at core scales. Nevertheless, we have firmly confirmed the evolutionary trend expected for the H/D ratio, with the N$_2$H$^+$/N$_2$D$^+$ ratio decreasing before the pre-stellar core phase, and increasing monotonically during the protostellar phase. We have also confirmed clearly that the two fractionation mechanisms are not related., 9 pages, 2 figures, accepted for publication in MNRAS

In this contribution we present the new experimental end-station to characterize XUV diffractive optics, such as Micro Channel Plates (MCPs) and other polycapillary optics, presently under commission at the Elettra synchrotron radiation laboratory (Trieste, Italy). To show the opportunities offered by these new optical devices for 3rd and 4th generation radiation sources, in this work we present also some patterns collected at different energies of the primary XUV radiation transmitted by MCP optical devices working in the normal incidence geometry.

The Near-Edge X-ray-Absorption Fine-Structure (NEXAFS) and X-ray Photoemission Spectroscopy (XPS) of short-chain oligothiophenes (thiophene, 2,2'-bithiophene, and 2,2':5',2 ''-terthiophene) in the gas phase have been measured in the sulfur L-2,L-3-edge region. The assignment of the spectral features is based on the relativistic two-component zeroth-order regular approximation time dependent density functional theory approach. The calculations allow us to estimate both the contribution of the spin-orbit splitting and of the molecular-field splitting to the sulfur binding energies and give results in good agreement with the experimental measurements. The deconvolution of the calculated S2p NEXAFS spectra into the two manifolds of excited states converging to the L-III and L-II edges facilitates the attribution of the spectral structures. The main S2p NEXAFS features are preserved along the series both as concerns the energy positions and the nature of the transitions. This behaviour suggests that the electronic and geometrical environment of the sulfur atom in the three oligomers is relatively unaffected by the increasing chain length. This trend is also observed in the XPS spectra. The relatively simple structure of S2p NEXAFS spectra along the series reflects the localized nature of the virtual states involved in the core excitation process. Published by AIP Publishing.

In order to dynamically characterise the opaque components of a building envelope subject to sinusoidal loadings in steady periodic regime conditions, the use of nondimensional periodic thermal transmittance is proposed. Such a parameter allows for the evaluation of the decrement factor and time lag that the heat flux undergoes while crossing the wall and the efficiency of the heat storage. For non-sinusoidal loadings, dynamic characterisation is obtained by the decrement factor, defined as the ratio between energy in a semi period entering the indoor environment and entering the wall and as the ratio between maximum heat fluxes entering the environment and the wall, and as the ratio between the minimum heat fluxes. These parameters allow to determine the heat storage capacity of the component, the maximum heat flux in summer and winter conditions and their time lags. The defined dynamic properties were calculated considering two commonly used walls and surrounding conditions that are representative of the effective operative conditions.

An analytical solution of the phase change problem, known as the Stefan or Moving Boundary Problem, in a PCM layer (phase change materials) subject to boundary conditions that are variable in time, is presented, in steady periodic regime. The two-phase Stefan Problem is resolved considering periodic boundary conditions of temperature or of heat flux, or even mixed conditions. This phenomenon is present in air-conditioned buildings, the walls of which use PCM layers to reduce thermal loads and energy requirements to be compensated by the plant. The resolution method used is one in which phasors allow the transformation of partial differential equations, describing conduction in the solid and liquid phase, into ordinary differential equations; furthermore the phasors allow transformation of the thermal balance equation at the bi-phase interface into algebraic equations. The Moving Boundary Problem is then reduced to a system of algebraic equations, the solution of which provides the position in time of the bi-phase interface and the thermal field of the layer. The solution obtained provides for different thermodynamic configurations that the layer can assume and makes the position of the bi-phase interface and the thermal field depend on the Fourier number and on the Stefan number calculated in the solid phase and in the liquid phase. In the case of two boundary conditions represented by a single sinusoidal oscillation, a general analysis, addressed in different thermodynamic configurations obtained by varying the Fourier and Stefan number, shows the calculation procedure of the steady and of the oscillating component of the position of the bi-phase interface, of the temperature field and of the heat flux field. In addition, we considered the particular case of a PCM layer with an oscillating temperature boundary condition on one face and a constant temperature on the other face. The analytical procedure was also used for an analysis dedicated to the thermal behaviour of Glauber’s salt subject to independent multi harmonic boundary conditions. This salt hydrate is one of the most studied, having a high latent fusion heat and a melting temperature that is suited for use in the walls of buildings.

The authors propose a methodology to schematize correctly the capacitive effects in the transmission of heat in the multilayered walls of buildings. An analytical study is presented related to a steady periodic regime allowing consideration of three external loads acting singularly or simultaneously: air temperature, apparent sky temperature and incident solar irradiation. Such a study is applied in the case of four traditional types of wall (A – brick wall, B – hollow wall, C – polarized brick wall, D – prefabricated wall). The expression of the oscillating heat flux, which penetrates the internal environment, and the conductive heat flux which penetrates the wall in contact with the external air, was obtained by means of the electrical analogy and the resolution of the equivalent circuit. It is demonstrated that the nondimensional periodic global transmittance, the ratio between the heat flux which is transferred to the indoor environment and the external heat flux, with the plant turned on, is the most suitable nondimensional parameter for the dynamic analysis of the walls. This parameter allows for the evaluation of all the typical dynamic quantities for the complete description of the thermal behavior of the walls.