509 research outputs found
Linear transformation distance for bichromatic matchings
Let be a set of points in general position, where is a
set of blue points and a set of red points. A \emph{-matching}
is a plane geometric perfect matching on such that each edge has one red
endpoint and one blue endpoint. Two -matchings are compatible if their
union is also plane.
The \emph{transformation graph of -matchings} contains one node for each
-matching and an edge joining two such nodes if and only if the
corresponding two -matchings are compatible. In SoCG 2013 it has been shown
by Aloupis, Barba, Langerman, and Souvaine that this transformation graph is
always connected, but its diameter remained an open question. In this paper we
provide an alternative proof for the connectivity of the transformation graph
and prove an upper bound of for its diameter, which is asymptotically
tight
The Spitzer Survey of the Small Magellanic Cloud: Discovery of Embedded Protostars in the HII Region NGC 346
We use Spitzer Space Telescope observations from the Spitzer Survey of the
Small Magellanic Cloud (S3MC) to study the young stellar content of N66, the
largest and brightest HII region in the SMC. In addition to large numbers of
normal stars, we detect a significant population of bright, red infrared
sources that we identify as likely to be young stellar objects (YSOs). We use
spectral energy distribution (SED) fits to classify objects as ordinary (main
sequence or red giant) stars, asymptotic giant branch stars, background
galaxies, and YSOs. This represents the first large-scale attempt at blind
source classification based on Spitzer SEDs in another galaxy. We firmly
identify at least 61 YSOs, with another 50 probable YSOs; only one embedded
protostar in the SMC was reported in the literature prior to the S3MC. We
present color selection criteria that can be used to identify a relatively
clean sample of YSOs with IRAC photometry. Our fitted SEDs indicate that the
infrared-bright YSOs in N66 have stellar masses ranging from 2 Msun to 17 Msun,
and that approximately half of the objects are Stage II protostars, with the
remaining YSOs roughly evenly divided between Stage I and Stage III sources. We
find evidence for primordial mass segregation in the HII region, with the most
massive YSOs being preferentially closer to the center than lower-mass objects.
Despite the low metallicity and dust content of the SMC, the observable
properties of the YSOs appear consistent with those in the Milky Way. Although
the YSOs are heavily concentrated within the optically bright central region of
N66, there is ongoing star formation throughout the complex and we place a
lower limit on the star formation rate of 3.2 x 10^-3 Msun/yr over the last ~1
Myr.Comment: 13 pages, 5 figures (3 in color), 2 tables. Accepted for publication
in Ap
Biomass pyrolysis in a Bubbling Fluidized Bed : Effect of biomass composition and reactor temperature
Flash pyrolysis of two types of woody biomass (Pine Wood, PW, and Green Wastes, GW) was carried out in a Bubbling Fluidized Bed of olivine particles between 700Ā°C and 850Ā°C. Experiments were conducted in a laboratory scale reactor (height of 2.5 m and internal diameter of 0.214 m) with continuous fuel feeding. Products distribution was determined through a global approach: incondensable gases yield were measured with an online microGC, condensable products yield, obtained by tar protocol, were quantified using GC-MS and Karl-Fischer titration and char yield was determined through high temperature combustion of the accumulated char at the end of each experiment.
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Crystallographic MAD Phasing Strategies Explored Using ELETTRA Sincrotrone Mn K-Edge Data to 2.1 Ć and Use of CHESS Establishes the Diffraction Resolution Limit as 0.92 Ć for the Protein Mn, Ca Concanavalin A
Multiwavelength anomalous dispersion (MAD) data have been collected from a single crystal of the protein concanavalin A so as to evaluate different combinations of wavelengths for crystallographic structure determination. Data were recorded to 2.1 Ć
resolution on a flash frozen crystal at three wavelengths about the Mn K-edge (1.8951 Ć
, 1.8940 Ć
, 1.800 Ć
) using synchrotron radiation at ELETTRA\u27s Sincrotrone Trieste \u27XRD\u27 beamline. This is one of the longest wavelength K-edge MAD studies undertaken to date. Anomalous and dispersive Patterson maps are seen to be of high quality and indicate a high occupancy for the manganese binding site. This is confirmed also in the MAD phase determination and electron density maps. Finally 0.92 Ć
data recorded at CHESS indicates the prospects available for combined phasing strategies based on MAD to medium/high resolution along with ultra high resolution data
Systematic review and network meta-analysis with individual participant data on cord management at preterm birth (iCOMP): study protocol
Introduction
Timing of cord clamping and other cord management strategies may improve outcomes at preterm birth. However, it is unclear whether benefits apply to all preterm subgroups. Previous and current trials compare various policies, including time-based or physiology-based deferred cord clamping, and cord milking. Individual participant data (IPD) enable exploration of different strategies within subgroups. Network meta-analysis (NMA) enables comparison and ranking of all available interventions using a combination of direct and indirect comparisons.
Objectives
(1) To evaluate the effectiveness of cord management strategies for preterm infants on neonatal mortality and morbidity overall and for different participant characteristics using IPD meta-analysis. (2) To evaluate and rank the effect of different cord management strategies for preterm births on mortality and other key outcomes using NMA.
Methods and analysis
Systematic searches of Medline, Embase, clinical trial registries, and other sources for all ongoing and completed randomised controlled trials comparing cord management strategies at preterm birth (before 37 weeksā gestation) have been completed up to 13 February 2019, but will be updated regularly to include additional trials. IPD will be sought for all trials; aggregate summary data will be included where IPD are unavailable. First, deferred clamping and cord milking will be compared with immediate clamping in pairwise IPD meta-analyses. The primary outcome will be death prior to hospital discharge. Effect differences will be explored for prespecified participant subgroups. Second, all identified cord management strategies will be compared and ranked in an IPD NMA for the primary outcome and the key secondary outcomes. Treatment effect differences by participant characteristics will be identified. Inconsistency and heterogeneity will be explored.
Ethics and dissemination
Ethics approval for this project has been granted by the University of Sydney Human Research Ethics Committee (2018/886). Results will be relevant to clinicians, guideline developers and policy-makers, and will be disseminated via publications, presentations and media releases
Smart E-Skin Cancer Care in Europe During and After the COVID-19 Pandemic: A Multidisciplinary Expert Consensus
Introduction: Melanoma is the deadliest of all the skin cancers and its incidence is increasing every year in Europe. Patients with melanoma often present late to the specialist and treatment is delayed for many reasons (delay in patient consultation, misdiagnosis by general practitioners, and/or limited access to dermatologists). BeyondĀ this, there are significant inequalities in skin cancer between population groups within the same country and between countries across Europe. The emergence of the COVID-19 pandemic only aggravated these health deficiencies.
Objectives: The aim was to create an expert opinion about the challenges in skin cancer management in Europe during the post COVID-19 acute pandemic and to identify and discuss the implementation of new technologies (including e-health and artificial intelligence defined as "Smart Skin Cancer Care") to overcome them.
Methods: For this purpose, an ad-hoc questionnaire with items addressing topics of skin cancer care was developed, answered independently and discussed by a multidisciplinary European panel of experts comprising dermatologists, dermato-oncologists, patient advocacy representatives, digital health technology experts, and health technology assessment experts.
Results: After all panel of experts discussions, a multidisciplinary expert opinion was created.
Conclusions: As a conclusion, the access to dermatologists is difficult and will be aggravated in the near future. This fact, together with important differences in Skin Cancer Care in Europe, suggest the need of a new approach to skin health, prevention and disease management paradigm (focused on integration of new technologies) to minimize the impact of skin cancer and to ensure optimal quality and equity
Combining alkali metals and zinc to harness heterometallic cooperativity in cyclic ester ring-opening polymerisation
Heterometallic cooperativity is an emerging strategy to elevate polymerisation catalyst performance. Here, we report the first heterotrimetallic Na/Zn(2) and K/Zn(2) complexes supported by a ProPhenol ligand, which deliver ābest of bothā in cyclic ester ring-opening polymerisation, combining the outstanding activity (Na/K) and good control (Zn(2)) of homometallic analogues. Detailed NMR studies and density-functional theory calculations suggest that the Na/Zn(2) and K/Zn(2) complexes retain their heterometallic structures in the solution-state. To the best of our knowledge, the K/Zn(2) analogue is the most active heterometallic catalyst reported for rac-lactide polymerisation (k(obs) = 1.7 Ć 10(ā2) s(ā1)), giving activities five times faster than the Na/Zn(2) complex. These versatile catalysts also display outstanding performance in Īµ-caprolatone and Ī“-valerolactone ring-opening polymerisation. These studies provide underpinning methodologies for future heterometallic polymerisation catalyst design, both in cyclic ester polymerisation and other ring-opening (co)polymerisation reactions
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Multinationality, R&D and productivity: evidence from the top R&D investors worldwide
This paper investigates the effects of multinationality on firm productivity, and contributes to the literature in two respects. First, we argue that multinationality affects productivity both directly and indirectly, through higher incentives to invest in R&D. Second, we maintain that the multinational depth and breadth have different direct effects on productivity and R&D. Using data from the top R&D investors in the world, we propose an econometric model with an R&D and a productivity equation that both depend on multinationality. We find: i) multinational depth has a positive effect on productivity, while the effect of multinational breadth is negative; ii) multinationality (along both dimensions) has a positive effect on R&D intensity, translating into an indirect positive effect on productivity; iii) the positive indirect effect is however not large enough to compensate the negative direct effect of multinational breadth
The capacity of schizophrenia and bipolar disorder individuals to make autonomous decisions about pharmacological treatments for their illness in real life: A scoping review
Abstract
Background and aim
Having decision making capacity is central to the exercise of autonomy in mental health care. The objective of this scoping review is to summarize the evidence on the capacity of people with schizophrenia or bipolar disorder to make decisions about their treatment in real life to support medical practice.
Methods
Systematic search of observational studies on the assessment of capacity of patients with schizophrenia, psychosis, or bipolar disorder to make healthcare and treatmentārelated decisions, conducted in any clinical setting published up to January 31, 2020 was performed. Free text searches and medical subject headings in English were combined in PubMed, Scopus, CINAHL, and PsycInfo. Publications were selected as per inclusion and exclusion criteria. The NewcastleāOttawa Scale for observational studies was used to assess the quality of publications.
Results
Thirty publications were reviewed. According to the NewcastleāOttawa Scale criteria, the publications reviewed were good quality. Findings showed that more than 70% of schizophrenia and schizoaffective disorder outpatients understood treatment options at the point of making decisions about their illness and healthcare. Patients treated voluntarily had considerably better scores for decisional capacity than those treated involuntarily. The burden of psychiatric symptoms could compromise decisional capacity temporarily. Decisionāmaking capacity improved over time from admission to discharge from hospital, and with treatment among psychiatry inpatients. Schizophrenia and bipolar disorder patients could be as competent as nonpsychiatric individuals in making decisions about their treatments in everyday life.
Conclusions
This scoping review provides a body of evidence for healthcare professionals in need of assessing the capacity of schizophrenia and bipolar disorder patients for autonomously decide about their treatments. Decisional capacity judgements should consider variations in capacity over time and be based on the type of decision to be made, the severity of symptoms, and the specific phase of the mental disorder.Ferrer funded the development of the study and the writing of the
manuscript with an unrestricted grant
Long term incidence of dementia, predictors of mortality and pathological diagnosis in older stroke survivors
Greater understanding of the risk factors and mechanisms of incident dementia in stroke survivors is needed for prevention and management. There is limited information on the long-term consequences and forms of incident dementia in older stroke survivors. We recruited 355 patients aged >75 years from hospital-based stroke registers into a longitudinal study 3 months after stroke. At baseline none of the patients had dementia. Patients were genotyped for apolipoprotein E and assessed annually for cognition and development of incident dementia over up to 8 years of follow-up. The effect of baseline vascular risk factors upon incidence of dementia and mortality were estimated by Cox proportional regression analyses adjusted for age and gender. Standard neuropathological examination was performed to diagnose the first 50 cases that came to autopsy. We found that the median survival from the date of the index stroke was 6.72 years (95% confidence intervals: 6.38ā7.05). During the follow-up of a mean time of 3.79 years, 23.9% of subjects were known to have developed dementia and 76.1% remained alive without dementia or died without dementia. The incidence of delayed dementia was calculated to be 6.32 cases per 100 person years whereas that for death or dementia was 8.62. Univariate and multivariate regression analyses showed that the most robust predictors of dementia included low (1.5 standard deviations below age-matched control group) baseline Cambridge Cognitive Examination executive function and memory scores, Geriatric Depression Scale score and three or more cardiovascular risk factors. Autopsy findings suggested that remarkably ā„75% of the demented stroke survivors met the current criteria for vascular dementia. Demented subjects tended to exhibit marginally greater neurofibrillary pathology including tauopathy and Lewy bodies and microinfarcts than non-demented survivors. Despite initial improvements in cognition following stroke in older stroke survivors, risk of progression to delayed dementia after stroke is substantial, but is related to the presence of vascular risk factors. Careful monitoring and treatment of modifiable vascular risk factors may be of benefit in preventing post-stroke dementia in the general population
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