Advanced composite materials are finding increasing application in aerospace, marine and many other industries due to their performance and structural efficiency. Maintenance inspection of these ...light-weight structures is a relatively new and difficult task for Non-Destructive Testing (NDT), which need robust methods to be applicable in industrial environments. In this paper, a new numerical–experimental procedure to detect size and depth of flat bottom holes in metallic and laminated composite structures by digital shearography (DISH) is proposed. The flaw detection capabilities of DISH have been evaluated by measuring the dynamic response of defects to applied stresses. Vibration dynamic loading is used to reveal flat bottom holes made with different sizes and placed at different depths in CFRP laminates. The shearographic methodology is based on the recognition of the (0 1) resonance mode per defect. A simplified model of thin circular plate, idealized above each flaw position, is used to calculate the natural frequency of vibrating defects. Then, the numerical difference between experimental resonance frequencies and those computationally obtained is minimized using an unconstrained optimization algorithm in order to calculate the defect depth. Considering the simplicity and rapidity of this technique, the laser shearography methodology is evaluated reliable as NDT method.
► We proposed a simple method to detect impact damage in composite structures. ► It uses a combination of shearography and optimization methods. ► Demonstrated a good accuracy in locating and sizing delaminations areas and depth.
A previous study reported the isolation of two mutants (LEI and LE2) of the plant pathogenic fungus Nectria haematococca (anamorph, Fusarium solani f. sp. cucurbitae) with macroconidia with reduced ...ability to adhere (Att-) to zucchini fruits and polystyrene. The adhesion-reduced phenotype in LEI and LE2 macroconidia is temperature sensitive and dependent on the concentration of nutrients. Classical genetic analysis of progeny derived from LE1 identified a mutation in a genetic locus, named Att1. The 90-kDa glycoprotein and macroconidial tip mucilage which were previously associated with the development of adhesion competence in Att+ macroconidia are specifically associated with macroconidia; neither is produced on microconidia, which are relatively nonadherent. However, macroconidia of both Att+ and Att- strains produce the 90-kDa glycoprotein and the macroconidial tip mucilage.
Synthesis of (−)-DAPD Sznaidman, Marcos L.; Du, Jinfa; Pesyan, Amir ...
Nucleosides, nucleotides & nucleic acids,
01/2004, Letnik:
23, Številka:
12
Journal Article
Recenzirano
A new synthesis of (−)-DAPD, suitable for large scale development, is described.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
44.
Structures and Reactions of P2N2: A Hybrid of Elemental N2 and P4? Kwon, Ohyun; Almond, Philip M; McKee, Michael L
The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory,
07/2002, Letnik:
106, Številka:
29
Journal Article
Recenzirano
A systematic study of all possible tetraatomic P2N2 structures has been made at the B3LYP/6-311+G(2df) and CASPT2(12e,12o)/ANO-L levels. A closed-shell butterfly C 2 v structure (A) is predicted to ...have the lowest energy on the tetraatomic P2N2 potential energy surface. The energies for dissociation of P2N2 to two P⋮N or to N2 and P2 have been examined. A closed-shell quasi-tetrahedral C 2 v structure of P2N2 (B) and a linear open-shell singlet P−N⋮N−P (E*) have been found to be kinetically stable to fragmentation or rearrangement at the CASPT2/ANO-L level. Several transition states have significant biradical character which reflects the orbital crossings that are found along reaction paths of least motion. The fragmentation reaction of P−N⋮N−P to 2P⋮N involves a trans-bent transition state that has a strong similarity to a known transition metal reaction.
As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether ...COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway.
This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation).
Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2%
4.9%; adjusted odds ratio aOR, 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1%
3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76).
Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks.
Increased efforts are required to prevent further losses to terrestrial biodiversity and the ecosystem services that it provides
. Ambitious targets have been proposed, such as reversing the ...declining trends in biodiversity
; however, just feeding the growing human population will make this a challenge
. Here we use an ensemble of land-use and biodiversity models to assess whether-and how-humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion, which is a major threat to biodiversity
. We show that immediate efforts, consistent with the broader sustainability agenda but of unprecedented ambition and coordination, could enable the provision of food for the growing human population while reversing the global terrestrial biodiversity trends caused by habitat conversion. If we decide to increase the extent of land under conservation management, restore degraded land and generalize landscape-level conservation planning, biodiversity trends from habitat conversion could become positive by the mid-twenty-first century on average across models (confidence interval, 2042-2061), but this was not the case for all models. Food prices could increase and, on average across models, almost half (confidence interval, 34-50%) of the future biodiversity losses could not be avoided. However, additionally tackling the drivers of land-use change could avoid conflict with affordable food provision and reduces the environmental effects of the food-provision system. Through further sustainable intensification and trade, reduced food waste and more plant-based human diets, more than two thirds of future biodiversity losses are avoided and the biodiversity trends from habitat conversion are reversed by 2050 for almost all of the models. Although limiting further loss will remain challenging in several biodiversity-rich regions, and other threats-such as climate change-must be addressed to truly reverse the declines in biodiversity, our results show that ambitious conservation efforts and food system transformation are central to an effective post-2020 biodiversity strategy.
Management of mechanical circulatory support in children with congenital heart disease (CHD) is challenging due to physiologic variations and anatomic limitations to device placement. In this study ...we examine the use of Berlin Heart EXCOR in CHD patients.
CHD patients were identified from the EXCOR Pediatric Study data set (2007 to 2010). Mortality and serious adverse events were compared between CHD and non-CHD cohorts, and predictors of poor outcomes in the CHD cohort were identified.
CHD was present in 29% (n = 59, 18 with 1-ventricle physiology) of all EXCOR patients (N = 204). Successful bridge (transplant or wean) was less likely in CHD patients compared with non-CHD patients (48% vs 80%; p < 0.01). Among CHD patients, no neonates, 25% of infants (30 days to 1 year) and 65% of children (>1 year) were successfully bridged. Pre-implant congenital heart surgery (CHS) and extracorporeal membrane oxygenation (ECMO) on the same admission occurred in 60% of children ≤1 year of age (83% of neonates, 50% of infants), with 8% survival. Regardless of age, patients who did not have CHS and ECMO had 61% survival. Smaller pump, pre-implant bilirubin >1.2 mg/dl and renal dysfunction were independently associated with mortality.
End-organ function at implant reliably predicts adverse outcomes and should be considered when making implant decisions. EXCOR use in neonates and infants with CHD should be approached cautiously. If patients have undergone pre-implant CHS and ECMO, EXCOR support may not provide any survival benefit. EXCOR support in non-infants with CHD is challenging but can be consistently successful with appropriate patient selection.
Recent data suggest that the Berlin Heart EXCOR Pediatric ventricular assist device is superior to extracorporeal membrane oxygenation for bridge to heart transplantation. Published data are limited ...to 1 in 4 children who received the device as part of the US clinical trial. We analyzed outcomes for all US children who received the EXCOR to characterize device outcomes in an unselected cohort and to identify risk factors for mortality to facilitate patient selection.
This multicenter, prospective cohort study involved all children implanted with the Berlin Heart EXCOR Pediatric ventricular assist device at 47 centers from May 2007 through December 2010. Multiphase nonproportional hazards modeling was used to identify risk factors for early (<2 months) and late mortality. Of 204 children supported with the EXCOR, the median duration of support was 40 days (range, 1-435 days). Survival at 12 months was 75%, including 64% who reached transplantation, 6% who recovered, and 5% who were alive on the device. Multivariable analysis identified lower weight, biventricular assist device support, and elevated bilirubin as risk factors for early mortality and bilirubin extremes and renal dysfunction as risk factors for late mortality. Neurological dysfunction occurred in 29% and was the leading cause of death.
Use of the Berlin Heart EXCOR has risen dramatically over the past decade. The EXCOR has emerged as a new treatment standard in the United States for pediatric bridge to transplantation. Three-quarters of children survived to transplantation or recovery; an important fraction experienced neurological dysfunction. Smaller patient size, renal dysfunction, hepatic dysfunction, and biventricular assist device use were associated with mortality, whereas extracorporeal membrane oxygenation before implantation and congenital heart disease were not.
Human rhinovirus (RV) infections are the principle cause of common colds and precipitate asthma and COPD exacerbations. There is currently no RV vaccine, largely due to the existence of ∼150 strains. ...We aimed to define highly conserved areas of the RV proteome and test their usefulness as candidate antigens for a broadly cross-reactive vaccine, using a mouse infection model. Regions of the VP0 (VP4+VP2) capsid protein were identified as having high homology across RVs. Immunization with a recombinant VP0 combined with a Th1 promoting adjuvant induced systemic, antigen specific, cross-serotype, cellular and humoral immune responses. Similar cross-reactive responses were observed in the lungs of immunized mice after infection with heterologous RV strains. Immunization enhanced the generation of heterosubtypic neutralizing antibodies and lung memory T cells, and caused more rapid virus clearance. Conserved domains of the RV capsid therefore induce cross-reactive immune responses and represent candidates for a subunit RV vaccine.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this paper, we are presenting a revised chronology of the best developed, longest (100 m) LPS in Hungary dating back 1.1 Ma: borehole Udvari-2A. It is based on a non-tuned age-depth model, built ...on the position of the Matuyama-Brunhes Boundary, Jaramillo and Olduvai Subchrons. Furthermore, on the assignment of formerly recorded uninterpreted geomagnetic reversals in both chrons. Other chronometric tools (AMS 14C dating, biostratigraphy, tephrostratigraphy) yielding absolute ages and/or ensuring validation of these were also used. Records of a Middle Pleistocene gastropod index fossil Neostyriaca corynodes (400 -140 ka) facilitated verification of ages between MIS 10 and MIS 6. Multiple age control points at 15, 25, 27, 45, 120, 191, 362, 430, 670, 780, 900, 990, 1070 ka were established for the last ca. 1.1 Ma. The resulting chronology is the best resolved independent one so far among Danubian Basin LPSs. In light of our data, the S3-S4 units were fused as S3 in all Serbian, and some Romanian sites and re-correlated with MIS 9. The results also point to a misassignment of the S5 units at these sites to MIS 13–15 leading to erroneous conclusions regarding paleoclimatic conditions and cyclicity. In our new stratigraphic scheme, these S5 paleosols were taken to represent the S4 paleosol and recorrelated with MIS 11. Finally, an ideal stratigraphic column dating back 1.1 Ma for SW Hungary was constructed and correlated with the Chinese loess/paleosol sequence of Xifeng and the benthic oxygen isotope record down to MIS 31.
•A new independent chronology for the past ca. 1 Ma of the best developed loess/paleosol sequence in Hungary is presented.•Age-depth model based on multiple magneto-, bio-, tephrostratigraphical and 14C data with high fidelity is built.•Former pan-Eurasian stratigraphic marker horizon of MIS 13-15 is refuted.•Some stratigraphic units assigned to MIS 11, 13-15 in this scheme are reassigned to MIS 9, MIS 11 in regional correlation.•A new ideal stratigraphic column for SW Hungary is constructed reaching down to MIS 31.