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The presence of minor bodies in exoplanetary systems is in most cases inferred through infra-red excesses, with the exception of exocomets. Even if over 35 years have passed since the first detection of exocomets around beta Pic, only ~ 25 systems are known to show evidence of evaporating bodies, and most of them have only been observed in spectroscopy. With the appearance of new high-precision photometric missions designed to search for exoplanets, such as CHEOPS, a new opportunity to detect exocomets is available. Combining data from CHEOPS and TESS we investigate the lightcurve of 5 Vul, an A-type star with detected variability in spectroscopy, to search for non periodic transits that could indicate the presence of dusty cometary tails in the system. While we did not find any evidence of minor bodies, the high precision of the data, along with the combination with previous spectroscopic results and models, allows for an estimation of the sizes and spatial distribution of the exocomets., Comment: Accepted for publication in MNRAS

Debris disks are the signposts of collisionally eroding planetesimal circumstellar belts, whose study can put important constraints on the structure of extrasolar planetary systems. The best constraints on the morphology of disks are often obtained from spatially resolved observations in scattered light. Here, we investigate the young (~16 Myr) bright gas-rich debris disk around HD121617. We use new scattered-light observations with VLT/SPHERE to characterize the morphology and the dust properties of this disk. From these properties we can then derive constraints on the physical and dynamical environment of this system, for which significant amounts of gas have been detected. The disk morphology is constrained by linear-polarimetric observations in the J band. Based on our modeling results and archival photometry, we also model the SED to put constraints on the total dust mass and the dust size distribution. We explore different scenarios that could explain these new constraints. We present the first resolved image in scattered light of the debris disk HD121617. We fit the morphology of the disk, finding a semi-major axis of 78.3$\pm$0.2 au, an inclination of 43.1$\pm$0.2{\deg} and a position angle of the major axis with respect to north, of 239.8$\pm$0.3{\deg}, compatible with the previous continuum and CO detection with ALMA. Our analysis shows that the disk has a very sharp inner edge, possibly sculpted by a yet-undetected planet or gas drag. While less sharp, its outer edge is steeper than expected for unperturbed disks, which could also be due to a planet or gas drag, but future observations probing the system farther from the main belt would help explore this further. The SED analysis leads to a dust mass of 0.21$\pm$0.02 M$_{\oplus}$ and a minimum grain size of 0.87$\pm$0.12 $\mu$m, smaller than the blowout size by radiation pressure, which is not unexpected for very bright col..., Comment: 12 pages, 7 figures. Accepted in A&A (06/02/2023)

Among iron oxide phases, magnetite Fe3O4 is often the preferred one for nanotechnological and biomedical applications because of its high saturation magnetization and low toxicity. Although there are several synthetic routes that attempt to reach magnetite nanoparticles NPs , they are usually referred as IONPs iron oxide NPs due to the great difficulty in obtaining the monophasic and stoichiometric Fe3O4 phase. Added to this problem is the common increase of size shape polydispersity when larger NPs D gt; 20 nm are synthesized. An unequivocal correlation between a nanomaterial and its properties can only be achieved by the production of highly homogeneous systems, which, in turn, is only possible by the continuous improvement of synthesis methods. There is no doubt that solving the compositional heterogeneity of IONPs while keeping them monodisperse remains a challenge for synthetic chemistry. Herein, we present a methodical optimization of the iron oleate decomposition method to obtain Fe3O4 single nanocrystals without any trace of secondary phases and with no need of postsynthetic treatment. The average dimension of the NPs, ranging from 20 to 40 nm, has been tailored by adjusting the total volume and the boiling point of the reaction mixture. Mössbauer spectroscopy and DC magnetometry have revealed that the NPs present a perfectly stoichiometric Fe3O4 phase. The high saturation magnetization 93 2 A m2 kg at RT and the extremely sharp Verwey transition at around 120 K shown by these NPs have no precedent. Moreover, the synthesis method has been refined to obtain NPs with octahedral morphology and suitable magnetic anisotropy, which significantly improves the magnetic hyperthemia performance. The heating power of properly PEGylated nano octahedrons has been investigated by AC magnetometry, confirming that the NPs present negligible dipolar interactions, which leads to an outstanding magnetothermal efficiency that does not change when the NPs are dispersed in environments with high viscosity and ionic strength. Additionally, the heat production of the NPs within physiological media has been directly measured by calorimetry under clinically safe conditions, reasserting the excellent adequacy of the system for hyperthermia therapies. To the best of our knowledge, this is the first time that such bulklike magnetite NPs with minimal size shape polydispersity, minor agglomeration, and exceptional heating power are chemically synthesized

Among iron oxide phases, magnetite (Fe3O4) is often the preferred one for nanotechnological and biomedical applications because of its high saturation magnetization and low toxicity. Although there are several synthetic routes that attempt to reach magnetite nanoparticles (NPs), they are usually referred as “IONPs” (iron oxide NPs) due to the great difficulty in obtaining the monophasic and stoichiometric Fe3O4 phase. Added to this problem is the common increase of size/shape polydispersity when larger NPs (D > 20 nm) are synthesized. An unequivocal correlation between a nanomaterial and its properties can only be achieved by the production of highly homogeneous systems, which, in turn, is only possible by the continuous improvement of synthesis methods. There is no doubt that solving the compositional heterogeneity of IONPs while keeping them monodisperse remains a challenge for synthetic chemistry. Herein, we present a methodical optimization of the iron oleate decomposition method to obtain Fe3O4 single nanocrystals without any trace of secondary phases and with no need of postsynthetic treatment. The average dimension of the NPs, ranging from 20 to 40 nm, has been tailored by adjusting the total volume and the boiling point of the reaction mixture. Mössbauer spectroscopy and DC magnetometry have revealed that the NPs present a perfectly stoichiometric Fe3O4 phase. The high saturation magnetization (93 (2) A·m2/kg at RT) and the extremely sharp Verwey transition (at around 120 K) shown by these NPs have no precedent. Moreover, the synthesis method has been refined to obtain NPs with octahedral morphology and suitable magnetic anisotropy, which significantly improves the magnetic hyperthemia performance. The heating power of properly PEGylated nano-octahedrons has been investigated by AC magnetometry, confirming that the NPs present negligible dipolar interactions, which leads to an outstanding magnetothermal efficiency that does not change when the NPs are dispersed in environments with high viscosity and ionic strength. Additionally, the heat production of the NPs within physiological media has been directly measured by calorimetry under clinically safe conditions, reasserting the excellent adequacy of the system for hyperthermia therapies. To the best of our knowledge, this is the first time that such bulklike magnetite NPs (with minimal size/shape polydispersity, minor agglomeration, and exceptional heating power) are chemically synthesized.

The currently existing magnetic hyperthermia treatments usually need to employ very large doses of magnetic nanoparticles MNPs and or excessively high excitation conditions H f gt; 1010 A m s to reach the therapeutic temperature range that triggers cancer cell death. To make this anticancer therapy truly minimally invasive, it is crucial the development of improved chemical routes that give rise to monodisperse MNPs with high saturation magnetization and negligible dipolar interactions. Herein, we present an innovative chemical route to synthesize Zn doped magnetite NPs based on the thermolysis of two kinds of organometallic precursors i a mixture of two monometallic oleates FeOl ZnOl , and ii a bimetallic ironzinc oleate Fe3 amp; 8722;yZnyOl . These approaches have allowed tailoring the size 10 amp; 8722;50 nm , morphology spherical, cubic, and cuboctahedral , and zinc content ZnxFe3 amp; 8722;xO4, 0.05 lt; x lt; 0.25 of MNPs with high saturation magnetization amp; 8805;90 Am2 kg at RT . The oxidation state and the local symmetry of Zn2 and Fe2 3 cations have been investigated by means of X ray absorption near edge structure XANES spectroscopy, while the Fe center distribution and vacancies within the ferrite lattice have been examined in detail through Mo amp; 776;ssbauer spectroscopy, which has led to an accurate determination of the stoichiometry in each sample. To achieve good biocompatibility and colloidal stability in physiological conditions, the ZnxFe3 amp; 8722;xO4 NPs have been coated with high molecular weight poly ethylene glycol PEG . The magnetothermal efficiency of ZnxFe3 amp; 8722;xO4 PEG samples has been systematically analyzed in terms of composition, size, and morphology, making use of the latest generation AC magnetometer that is able to reach 90 mT. The heating capacity of Zn0.06Fe2.94O4 cuboctahedrons of 25 nm reaches a maximum value of 3652 W g at 40 kA m and 605 kHz , but most importantly, they reach a highly satisfactory value 600 W g under strict safety excitation conditions at 36 kA m and 125 kHz . Additionally, the excellent heating power of the system is kept identical both immobilized in agar and in the cellular environment, proving the great potential and reliability of this platform for magnetic hyperthermia therapies

Background Hematopoietic stem cell transplantation (HSCT) is challenging because of economic, educational, and organizational reasons. Argentina is a middle-income country. HSML is a public pediatric hospital with an HSCT unit halted its services in July 2014. Among the reasons for suspending the services were healthcare providers(HCP) burn out, miscommunication, and tasks breakdown. The HSCT service resumed in December 2014. Objectives The primary objective was to describe and share the experiences in resuming the HSCT service by using a multicomponent strategic plan and interventions. The secondary objective was to review the outcomes. Methods Our strategic plan consisted of four main components: (1) Use of quality improvement tools for quality assessment and management (Six Sigma quality improvement processes, root-cause analysis, process maps, and brain storming); (2) participate in international collaborative networks (St. Jude Global Alliance and PRINCIPAL networks, the BFM-Forum-SCT, Sick-Kids Hospital, Canada); (3) participate in national and international training programs; and (4) improve healthcare delivery and organization processes, including infection care and prevention (develop and standardize all HSCT care delivery procedures). Results and Outcomes Healthcare facilities and services auditing and accreditation: An infection prevention and control program was started. This program managed: air and ventilation system improvement (air-conditioning, HEPA filters, positive pressure) and the creation of 47 standardized operating procedures. The HSCT wards were audited 3 times, and received accreditation (2018) by a national accreditation agency in Argentina. Human resources: 7 new doctors and 4 nurses were hired, the nurse:patient ratio was 1:2. 4 doctors attended a course for SPSS software®management; 6 doctors attended different American Society of Hematology H-Clinical Research Institute meetings. Personnel felt a reduction in the level of burn-out after the implementation of a plan designed by all stakeholders. Family information: 28 families received training for management of immunosuppressed patients. Scientific production: 4 clinical trials were accepted in indexed journals, 23 abstracts were presented in scientific meetings, and 27 educational national and international meetings were attended by personnel. Data management: Creation of a patient database (n = 310 patients), and registration of infection episodes for monthly assessment and monitoring patterns of infections (n = 776 events). Outcomes: During 2015–2019, 73 children were transplanted: autologous 11 (15%), match sibling donor (MSD) 35 (48%) and match unrelated donors (MUD) 27 (37%) Median age was 6 years of age (IQR 2–9), 53% were male, and 60% were acute leukemias. At a mean median time of 12 months (IQR 5–18), the overall survival by Kaplan–Meier for MSD and MUD was similar (62.3 ± 10.7% and 54.2 ± 15.0%, log-rank P = 0.54). The cumulative incidence of treatment-related mortality (log-rank P = 0.31), cumulative incidence of relapse (LR P = 0.99) were comparable as well. Infection rates were 40.5% and 69.6% in MSD vs. MUD (OR 3.36; 95% CI 1.14–9.98; P = 0.038). Conclusion The strategic plan implemented allowed us to offer optimal care to children in a public hospital without further financial cost and more satisfied HCPs. Results are comparable to published literature. Implementation of quality improvement interventions leads to the success of our program. Education and collaboration with national and international networks assisted improvement of the standard of care.

Our primary objective was to describe the incidence of proven or probable invasive fungal infections (IFIs), a devastating complication of hematopoietic stem cell transplant (HSCT), in HCST in a middle-income country. Secondary objectives were to describe factors associated with IFIs and outcomes. In this single center retrospective study, pediatric patients who underwent a first allogeneic or autologous HSCT from 1998 to 2016 were included. Of the 251 HSCT recipients: 143 transplants were allogeneic and 108 were autologous. Overall, 23 (9%) experienced an IFI, mostly due to yeasts (83%). IFIs were more common in allogeneic HSCT (18/143, 13%) than in autologous HSCT (5/108, 5%; P = .045). Of the 23 patients with IFIs, 14 (61%) died, but only 1 directly from IFI (pulmonary aspergillosis). Overall survival at 3 years was 0.42 ± 0.11 in patients with IFIs and 0.60 ± 0.37 in those without IFIs (P = .049). In Argentina, IFIs during HSCT are common. Recipients of allogeneic HSCT are at higher risk, and IFI is associated with reduced overall survival. Future work should focus on interventions to reduce and improve IFI outcomes in children undergoing transplants in low- and middle-income countries.

A partir de pesquisa realizada com dez adolescentes do sexo feminino das camadas médias de Ribeirão Preto-SP, este trabalho analisa a constituição da identidade de gênero dessas adolescentes, suas relações com a família e com o grupo de pares e os vínculos afetivos com parceiros com os quais se fica e com namorados. A análise dos dados sugere que apesar da mudança nos padrões culturais e da nova posição assumida pelas mulheres, a constituição da identidade de gênero das adolescentes é marcada por ambigüidades em torno dos papéis femininos, o que contribui para que elas incorporem essas mesmas ambigüidades em sua conduta. On the basis of a survey of middle-class adolescent girls from Ribeirão Preto, the present study analyzes the constitution of gender identity of these girls, their relations with family and with peer group and the affective ties with occasional or steady boy friends. Analysis of the data suggests that, despite the change in cultural patterns and of the new positions of women, the constitution of gender identity of girls is marked by ambiguities about female roles, a fact that causes these girls to incorporate these same ambiguities into their behavior.

A partir de pesquisa realizada com dez adolescentes do sexo feminino das camadas médias de Ribeirão Preto-SP, este trabalho analisa a constituição da identidade de gênero dessas adolescentes, suas relações com a família e com o grupo de pares e os vínculos afetivos com parceiros com os quais se fica e com namorados. A análise dos dados sugere que apesar da mudança nos padrões culturais e da nova posição assumida pelas mulheres, a constituição da identidade de gênero das adolescentes é marcada por ambigüidades em torno dos papéis femininos, o que contribui para que elas incorporem essas mesmas ambigüidades em sua conduta. On the basis of a survey of middle-class adolescent girls from Ribeirão Preto, the present study analyzes the constitution of gender identity of these girls, their relations with family and with peer group and the affective ties with occasional or steady boy friends. Analysis of the data suggests that, despite the change in cultural patterns and of the new positions of women, the constitution of gender identity of girls is marked by ambiguities about female roles, a fact that causes these girls to incorporate these same ambiguities into their behavior.

We present optical spectroscopy observations of 145 high-mass pre-main sequence candidates from the catalogue of Vioque et al. (2020). From these, we provide evidence for the Herbig nature of 128 sources. This increases the number of known objects of the class by $\sim50\%$. We determine the stellar parameters of these sources using the spectra and Gaia EDR3 data. The new sources are well distributed in mass and age, with 23 sources between $4$-$8$ M$_{\odot}$ and 32 sources above $8$ M$_{\odot}$. Accretion rates are inferred from H$\alpha$ and H$\beta$ luminosities for 104 of the new Herbigs. These accretion rates, combined with previous similar estimates, allow us to analyze the accretion properties of Herbig stars using the largest sample ever considered. We provide further support to the existence of a break in accretion properties at $\sim3$-$4$ M$_{\odot}$, which was already reported for the previously known Herbig stars. We re-estimate the potential break in accretion properties to be at $3.87^{+0.38}_{-0.96}$ M$_{\odot}$. As observed for the previously known Herbig stars, the sample of new Herbig stars independently suggests intense inner-disk photoevaporation for sources with masses above $\sim7$ M$_{\odot}$. These observations provide robust observational support to the accuracy of the Vioque et al. (2020) catalogue of Herbig candidates., Comment: Published in The Astrophysical Journal. Received 1 January 2022 / Accepted 2 March 2022 (14 pages, 8 figures). Tables B1, B2, and B3 are available at the CDS in their entirety in machine-readable form