Strain engineering in Ge/GeSn core/shell nanowires

Strain engineering in Sn-rich group IV semiconductors is a key enabling factor to exploit the direct band gap at mid-infrared wavelengths. Here, we investigate the effect of strain on the growth of GeSn alloys in a Ge/GeSn core/shell nanowire geometry. Incorporation of Sn content in the 10-20 at.% range is achieved with Ge core diameters ranging from 50nm to 100nm. While the smaller cores lead to the formation of a regular and homogeneous GeSn shell, larger cores lead to the formation of multi-faceted sidewalls and broadened segregation domains, inducing the nucleation of defects. This behavior is rationalized in terms of the different residual strain, as obtained by realistic finite element method simulations. The extended analysis of the strain relaxation as a function of core and shell sizes, in comparison with the conventional planar geometry, provides a deeper understanding of the role of strain in the epitaxy of metastable GeSn semiconductors

High-Intensity Ultrasonication as an Innovative Approach for the Softening of Wooden Breast Meat in Broilers

Considering the remarkable implications exerted by the occurrence of wooden breast (WB) abnormality on meat tenderness and marketability, the poultry processing industry demands the implementation of postmortem procedures that can improve the textural traits of chicken breasts affected by this defect. Within this scenario, this study aimed at exploring the effectiveness of high-intensity ultrasonication (HIU) in attenuating the toughness of WB fillets and evaluating its effects on the main technological properties and quality characteristics of chicken breast meat. Overall outcomes showed that HIU significantly reduced (P<0.01) the compression forces of both unaffected and WB raw meat without negatively affecting the main meat quality traits and technological properties, such as color and water holding capacity. The significant (P<0.05) increase in myofibrillar fragmentation index (MFI) observed in unaffected fillets might hint at an alteration of myofibril integrity following the mechanical action of ultrasonic waves. However, despite the effectiveness of HIUin improving the textural traits of raw WB meat, overall outcomes obtained through western blot and MFI analyses suggested that HIU did not remarkably alter the microstructure of myopathic muscles. The myodegenerative lesions typically occurring in WB muscles may have partially disguised the mechanical effects of ultrasonic waves on muscle cells’ structures, making the elucidation of the mechanisms that lead to the softening of WB meat particularly complex

Polyblend Nanofibers to Regenerate Gingival Tissue: A Preliminary In Vitro Study

Aim: The regeneration of small periodontal defects has been considered an important divide and challenging issue for dental practitioners. The aim of this preliminary in vitro study was to analyze the effects of polycaprolactone (PCL) nanofibers enriched with hyaluronic acid and vitamin E vs. nude nanofibers on gingival fibroblasts activity, an innovative graft for periodontal soft tissue regeneration purposes. Methods: Nanofibers were produced in PCL (NF) or PCL enriched with hyaluronic acid and vitamin E (NFE) by electrospinning technique. NF and NFE were stereologically and morphologically characterized by scanning electron microscope (SEM), and composition was analyzed by infrared spectroscopy. Human fibroblasts were obtained from one gingival tissue fragment (HGF) and then seeded on NF, NFE, and plastic (CT). Cell adhesion and morphology were evaluated using SEM at 24 h and cell viability after 24, 48, and 72 h by alamarBlue® assay. Gene expression for COL-I, LH2b, TIMP-1, PAX, and VNC was analyzed by real-time RT-PCR in samples run in triplicate and GAPDH was used as housekeeping gene. Slot blot analysis was performed and immunoreactive bands were revealed for MMP-1 and COL-I. YAP and p-YAP were analyzed by Western blot and membranes were reprobed by α-tubulin. Statistical analysis was performed. Results: IR spectrum revealed the presence of PCL in NF and PCL and vitamin E and hyaluronic acid in NFE. At 24 h, HGF adhered on NF and NFE conserving fibroblast like morphology. At 72 h from seeding, statistically significant differences were found in proliferation of HGF cultured on NF compared to NFE. Expression of genes (LH2b, TIMP-1, and MMP-1) and proteins (COL-I) related to collagen turnover revealed a reduction of COL-1 secretion in cells cultured on NF and NFE compared to CT; however, NFE stimulated cross-linked collagen deposition. Mechanosensor genes (PAX, VNC, and YAP) were upregulated in HGF on NF while they were decreased in cells grown on NFE. Conclusion: Preliminary data suggest that PCL-enriched nanofibers could represent a support to induce HGF proliferation, adhesion, collagen cross-linking, and to reduce collagen degradation, therefore favoring collagen deposition in gingival connective tissue

Rapporto tecnico sulle attività di campionamento della “Campagna Oceanografica CISAS_1” Augusta-Priolo 19-23 ottobre 2017

Le attività di campionamento ed acquisizione dati svolte durante la campagna CISAS_1 si inseriscono in seno al progetto “Centro internazionale di studi avanzati su ambiente ed impatti su ecosistema e salute umana (CISAS)” del CNR. Tra gli obiettivi principali del progetto, lo sviluppo di una complessa e decisa azione di ricerca scientifica volta ad una profonda comprensione dei fenomeni di inquinamento ambientale e dei loro risvolti sull’ecosistema e la salute umana. Le aree di indagine del progetto sono rappresentate dai Siti di Interesse Nazionale di Priolo, Milazzo-Pace del Mela e Crotone che, per specificità e modalità di impatto antropogenico sull’ambiente, l’ecosistema e la salute umana, coprono un ampio spettro di tipologie di interesse

Non-infectious uveitis burden on quality of life and work impairment assessed through different psychometric questionnaires

Background: The purpose of this study was to evaluate the association between a novel psychometric 12-item questionnaire (U-qest) and other validated questionnaires to assess quality of life and work impairment in patients with non-infectious uveitis. Methods: Data were collected at baseline and 3 months postbaseline using U-qest and two other validated questionnaires: The National Eye Institute 25-Item Visual Function Questionnaire (VFQ-25) and the 12-Item Short-Form Health Survey (SF-12). Results: A total of 136 patients (52.2% female) aged 47.9 ± 14.8 years (mean ± SD) were enrolled in 14 uveitis referral centres. U-qest correlated moderately with VFQ-25 and SF-12 at baseline and at 3 months. Both U-qest and VFQ-25 scores improved as disease improved; however, U-qest also detected improvement in patients for whom VFQ-25 scores did not improve. Disease activity was shown to significantly affect activity impairment. Patients and physicians expressed positive perceptions regarding the use and benefit of this instrument. U-qest showed very good reliability in terms of internal consistency (Cronbach’s alpha = 0.91). Conclusions: U-qest can be considered a useful tool to assess the burden of uveitis on quality of life

Hydrogel-in-hydrogel live bioprinting for guidance and control of organoids and organotypic cultures

Three-dimensional hydrogel-based organ-like cultures can be applied to study development, regeneration, and disease in vitro. However, the control of engineered hydrogel composition, mechanical properties and geometrical constraints tends to be restricted to the initial time of fabrication. Modulation of hydrogel characteristics over time and according to culture evolution is often not possible. Here, we overcome these limitations by developing a hydrogel-in-hydrogel live bioprinting approach that enables the dynamic fabrication of instructive hydrogel elements within pre-existing hydrogel-based organ-like cultures. This can be achieved by crosslinking photosensitive hydrogels via two-photon absorption at any time during culture. We show that instructive hydrogels guide neural axon directionality in growing organotypic spinal cords, and that hydrogel geometry and mechanical properties control differential cell migration in developing cancer organoids. Finally, we show that hydrogel constraints promote cell polarity in liver organoids, guide small intestinal organoid morphogenesis and control lung tip bifurcation according to the hydrogel composition and shape

SN 2021hpr and its two siblings in the Cepheid calibrator galaxy NGC 3147: A hierarchical BayeSN analysis of a Type Ia supernova trio, and a Hubble constant constraint

To improve Type Ia supernova (SN Ia) standardisability, the consistency of distance estimates to siblings -- SNe in the same host galaxy -- should be investigated. We present Young Supernova Experiment Pan-STARRS-1 $grizy$ photometry of SN 2021hpr, the third spectroscopically confirmed SN Ia in the high-stellar-mass Cepheid-calibrator galaxy NGC 3147. We analyse NGC 3147's trio of SN Ia siblings: SNe 1997bq, 2008fv and 2021hpr, using a new version of the BayeSN model of SN Ia spectral-energy distributions, retrained simultaneously using optical-NIR $BgVrizYJH$ (0.35--1.8 $\mu$m) data. The distance estimates to each sibling are consistent, with a sample standard deviation $\lesssim$0.01 mag, much smaller than the total intrinsic scatter in the training sample: $\sigma_0\approx0.09$ mag. Fitting normal SN Ia siblings in three additional galaxies, we estimate a $\approx$90% probability that the siblings' intrinsic scatter is smaller than $\sigma_0$. We build a new hierarchical model that fits light curves of siblings in a single galaxy simultaneously; this yields more precise estimates of the common distance and the dust parameters. Fitting the trio for a common dust law shape yields $R_V=2.69\pm0.52$. Our work motivates future hierarchical modelling of more siblings, to tightly constrain their intrinsic scatter, and better understand SN-host correlations. Finally, we estimate the Hubble constant, using a Cepheid distance to NGC 3147, the siblings trio, and 109 Hubble flow ($0.01 < z_{\rm{CMB}} < 0.08$) SNe Ia; marginalising over the siblings' and population's intrinsic scatters, and the peculiar velocity dispersion, yields $H_0=77.9\pm6.5 \text{ km s}^{-1}\text{Mpc}^{-1}$.Comment: Submitted to MNRAS; 30 pages, 22 figure

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Twofold origin of strain-induced bending in core-shell nanowires:The GaP/InGaP case

\u3cp\u3eNanowires have emerged as a promising platform for the development of novel and high-quality heterostructures at large lattice misfit, inaccessible in a thin film configuration. However, despite core-shell nanowires allowing a very efficient elastic release of the misfit strain, the growth of highly uniform arrays of nanowire heterostructures still represents a challenge, for example due to a strain-induced bending morphology. Here we investigate the bending of wurtzite GaP/In \u3csub\u3ex\u3c/sub\u3e Ga\u3csub\u3e1-x\u3c/sub\u3eP core-shell nanowires using transmission electron microscopy and energy dispersive x-ray spectroscopy, both in terms of geometric and compositional asymmetry with respect to the longitudinal axis. We compare the experimental data with finite element method simulations in three dimensions, showing that both asymmetries are responsible for the actual bending. Such findings are valid for all lattice-mismatched core-shell nanowire heterostructures based on ternary alloys. Our work provides a quantitative understanding of the bending effect in general while also suggesting a strategy to minimise it.\u3c/p\u3