1,092 research outputs found
Surface properties of chitin-glucan nanopapers from Agaricus bisporus
The structural component of fungal cell walls comprises of chitin covalently bonded to glucan; this constitutes a native composite material (chitin-glucan, CG) combining the strength of chitin and the toughness of glucan. It has a native nano-fibrous structure in contrast to nanocellulose, for which further nanofibrillation is required. Nanopapers can be manufactured from fungal chitin nanofibrils (FChNFs). FChNF nanopapers are potentially applicable in packaging films, composites, or membranes for water treatment due to their distinct surface properties inherited from the composition of chitin and glucan. Here, chitin-glucan nanofibrils were extracted from common mushroom (Agaricus bisporus) cell walls utilizing a mild isolation procedure to preserve the native quality of the chitin-glucan complex. These extracts were readily disintegrated into nanofibre dimensions by a low-energy mechanical blending, thus making the extract dispersion directly suitable for nanopaper preparation using a simple vacuum filtration process. Chitin-glucan nanopaper morphology, mechanical, chemical, and surface properties were studied and compared to chitin nanopapers of crustacean (Cancer pagurus) origin. It was found that fungal extract nanopapers had distinct physico-chemical surface properties, being more hydrophobic than crustacean chitin
The Rationale of Autologously Prepared Bone Marrow Aspirate Concentrate for use in Regenerative Medicine Applications
Autologously prepared bone marrow aspirate concentrates, have the potential to play an adjunctive role in various patient pathologies that have not been able to heal with conventional treatment modalities. The use of bone marrow aspirate (BMA) and concentrates in regenerative medicine treatment plans and clinical applications is based on the fact that bone marrow cells, including progenitor and nucleated cells, platelets, and other cytokines, support in tissue healing and tissue regenerative processes. The use of concentrated BMA cells focuses primarily on mesenchymal stem cells (MSCs), with the ability to self-renew and differentiate into multiple cell types. Concentrated bone marrow cells can be retrieved from harvested BMA and ensuing minimal manipulative cell processing techniques, executed at point of care (POC). The application of bone marrow biological therapies may offer solutions in musculoskeletal pathologies, spinal disorders, chronic wound care, and critical limb ischemia (CLI), to effectively change the local microenvironment to support in tissue healing and facilitate tissue regeneration. This chapter will address the cellular content of bone marrow tissue, harvesting and preparation techniques, and discuss the biological characteristics of individual marrow cells, their inter-connectivity, and deliberate on the effects of BMA concentration
Ultrasound Findings of Delayed‐Onset Muscle Soreness
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135570/1/jum201635112517.pd
Socio economic crisis and mortality. Epidemiological testimony of the financial collapse of Argentina
BACKGROUND: Natural disasters, war, and terrorist attacks, have been linked to cardiac mortality. We sought to investigate whether a major financial crisis may impact on the medical management and outcomes of acute coronary syndromes.
METHODS: We analyzed the Argentine cohort of the international multicenter Global Registry of Acute Coronary Events (GRACE). The primary objective was to estimate if there was an association between the financial crisis period (April 1999 to December 2002) and in- hospital cardiovascular mortality, with the post-crisis period (January 2003 to September 2004) as the referent. Each period was defined according to the evolution of the Gross Domestic Product. We investigated the demographic characteristics, diagnostic and therapeutic procedures, morbidity and mortality.
RESULTS: We analyzed data from 3220 patients, 2246 (69.8%) patients in the crisis period and 974 (30.2%) in the post-crisis frame. The distribution of demographic and clinical baseline characteristics were not significantly different between both periods. During the crisis period the incidence of in-hospital myocardial infarction was higher (6.9% Vs 2.9%; p value \u3c 0.0001), as well as congestive heart failure (16% Vs 11%; p value \u3c 0.0001). Time to intervention with angioplasty was longer during the crisis, especially among public sites (median 190 min Vs 27 min). The incidence proportion of mortality during hospitalization was 6.2% Vs 5.1% after crisis. The crude OR for mortality was 1.2 (95% C.I. 0.87, 1.7). The odds for mortality were higher among private institutions {1.9 (95% C.I. 0.9, 3.8)} than for public centers {1.2 (95% C.I. 0.83, 1.79)}. We did not observe a significant interaction between type of hospital and crisis.
CONCLUSION: Our findings suggest that the financial crisis may have had a negative impact on cardiovascular mortality during hospitalization, and higher incidence of medical complications
Structural Characterization, Magnetic and Luminescent Properties of Praseodymium(III)‐4,4,4‐Trifluoro‐1‐(2‐Naphthyl)Butane‐1,3‐Dionato(1‐)Complexes
Four new Pr(III) mononuclear complexes of formula [Pr(ntfa)3(MeOH)2] (1), [Pr(ntfa)3(bipy)2] (2), [Pr(ntfa)3(4,4′-Mt2bipy)] (3) and [Pr(ntfa)3(5,5′-Me2bipy)] (4), where ntfa = 4,4,4-trifuoro-1-(naphthalen-2-yl)butane-1,3-dionato(1-), 5,5′-Me2bipy = 5,5′-dimethyl-2,2′-dipyridine, 4,4′-Mt2bipy = 4,4′-dimethoxy-2,2′-dipyridine, have been synthesized and structurally characterized. The complexes display the coordination numbers 8 for 1, 3 and 4, and 10 for 2. Magnetic measurements of complexes 1-4 were consistent with a magnetically uncoupled Pr3+ ion in the 3H4 ground state. The solid state luminescence studies showed that the ancillary chelating bipyridyl ligands in the 2-4 complexes greatly enhance the luminescence emission in the visible and NIR regions through efficient energy transfer from the ligands to the central Pr3+ ion; behaving as "antenna" ligands
Generating hypotheses about care needs of high utilizers: lessons from patient interviews.
Informed by a largely secondary and quantitative literature, efforts to improve care and outcomes for complex patients with high levels of emergency and hospital-based health care utilization have offered mixed results. This qualitative study identifies psychosocial factors and life experiences described by these patients that may be important to their care needs. Semi-structured interviews were conducted with 19 patients of the Camden Coalition of Healthcare Providers\u27 Care Management Team. Investigators coded transcripts using a priori and inductively-derived codes, then identified 3 key themes: (1) Early-life instability and traumas, including parental loss, unstable or violent relationships, and transiency, informed many participants\u27 health and health care experiences; (2) Many high utilizers described a history of difficult interactions with health care providers during adulthood; (3) Over half of the participants described the importance to their well-being of positive and caring relationships with primary health care providers and the outreach team. Additionally, the transient and vulnerable nature of this complex population posed challenges to follow-up, both for research and care delivery. These themes illuminate potentially important hypotheses to be explored in more generalizable samples using robust and longitudinal methods. Future work should explore the prevalence and impact of adverse childhood experiences among high utilizers, and the different types of relationships they have with providers. Investigators should test new modes of care delivery that attend to patients\u27 trauma histories. This qualitative study was well suited to provide insight into the life stories of these complex, vulnerable patients, informing research questions for further investigation
Magnetic and Luminescence Properties of 8-Coordinated Pyridyl Adducts of Samarium(III) Complexes Containing 4,4,4-Trifluoro-1-(naphthalen-2-yl)-1,3-butanedionate
A novel series of polypyridyl adducts, [Sm(ntfa)3(NN)] (2-4), with ntfa = 4,4,4-trifluoro-1-(naphthalen-2-yl)-1,3-butanedionate, NN = 2,2′-bipyridine (bipy), 4,4′-dimethyl-2,2′-bipyridine (4,4′-Me2bipy), and 5,5′-dimethyl-2,2′-bipyridine (5,5′-Me2bipy) were synthesized from the precursor complex [Sm(ntfa)3(MeOH)2] (1) and the corresponding pyridyl ligands. Single X-ray crystallography showed that the complexes displayed 8-coordinated geometry. The solid pyridyl adducts 2-4 exhibited emission of luminescence in the NIR and visible regions with close quantum yields (QY = 0.20-0.25%). The magnetic data of 1-4 showed larger values than those expected for magnetically noncoupled Sm(III) complexes in the 6H5/2 ground state, with no saturation on the applied high magnetic field static at a temperature of 2 K
Different topologies in three manganese-μ-azido 1D compounds: magnetic behavior and DFT-quantum Monte Carlo calculations
The syntheses and structural characterization of three new monodimensional azido-bridged manganese(II) complexes with empirical formulae [Mn(N3)2(aminopyz)2]n (1), [Mn(N3)2(4-azpy)2]n (2) and [Mn(N3)2(4-Bzpy)2]n (3) (pyz = pyrazine (1,4-diazine)), 4-azpy = 4-azidopyridine and 4-Bzpy = 4-benzoylpyridine) are reported. 1 is a monodimensional compound with double EO azido bridges, 2 is an alternating monodimensional compound with double end-on and double end-to-end azido bridges in the sequence di-EO-di-EE and 3 is a monodimensional compound with double end-on and double end-to-end azido bridges in the sequence di-EO-di-EO-diEO-di-EO-di-EE. The magnetic properties of 1-3 are reported. Periodic DFT calculations were performed to estimate the J values and quantum Monte Carlo simulations were carried out using the calculated J values to check their accuracy in comparison with the experimental magnetic measurements. From this theoretical analysis, two appealing features of the di-EO Mn(II) compounds can be extracted: first, the exchange coupling becomes more ferromagnetic when the Mn-N-Mn bridging angle becomes larger and the spin density of the bridging nitrogen atoms has an opposite sign to that of the Mn(II) centers
Structure, DFT Calculations, and Magnetic Characterization of Coordination Polymers of Bridged Dicyanamido-Metal(II) Complexes
Three coordination polymers of metal(II)-dicyanamido (dca) complexes with 4-methoxypyridine-N-oxide (4-MOP-NO); namely, catena-[Co(µ1,5-dca)2(4-MOP-NO)2] (1), catena-[Mn(µ1,5-dca)2(4-MOP-NO)2] (2), catena-[Cd(µ1,5-dca)2(4-MOP-NO)2] (3), and the mononuclear [Cu(κ1dca)2(4-MOP-NO)2] (4), were synthesized in this research. The complexes were analyzed by single crystal X-ray diffraction as well as spectroscopic methods (UV/vis, IR). The polymeric 1-D chains in complexes 1-3 were achieved by the doubly µ1,5-bridging dca ligands and the O-donor atoms of two axial 4-MOP-NO molecules in trans configuration around the distorted M(II) octahedral. On the other hand, the two "trans-axial" pyridine-N-oxide molecules in complexes 2 and 3 display opposite orientation (s-trans). The DFT (density functional theory) computational studies on the complexes 1-3 were consistent with the experimentally observed crystal structures. Compounds 1 and 2 display weak antiferromagnetic coupling between metal ions (J = −10.8 for 1 and −0.35 for 2)
Magnetic and Luminescence Properties of 8-Coordinate Holmium(III) Complexes Containing 4,4,4-Trifluoro-1-Phenyl and 1-(Naphthalen-2-yl)-1,3-Butanedionates.
A new series of mononuclear Ho3+ complexes derived from the β-diketonate anions: 4,4,4-trifluoro-1-phenyl-1,3-butanedioneate (btfa−) and 4,4,4-trifuoro-1-(naphthalen-2-yl)-1,3-butanedionate (ntfa−) have been synthesized, [Ho(btfa)3(H2O)2] (1a), [Ho(ntfa)3(MeOH)2] (1b), (1), [Ho(btfa)3(phen)] (2), [Ho(btfa)3(bipy)] (3), [Ho(btfa)3(di-tbubipy)] (4), [Ho(ntfa)3(Me2bipy)] (5), and [Ho(ntfa)3(bipy)] (6), where phen is 1,10-phenantroline, bipy is 2,2′-bipyridyl, di-tbubipy is 4,4′-di-tert-butyl-2,2′-bipyridyl, and Me2bipy is 4,4′-dimethyl-2,2′-bipyridyl. These compounds have been characterized by elemental microanalysis and infrared spectroscopy as well as single-crystal X-ray difraction for 2-6. The central Ho3+ ions in these compounds display coordination number 8. The luminescence-emission properties of the pyridyl adducts 2-6 display a strong characteristic band in the visible region at 661 nm and a series of bands in the NIR region (excitation wavelengths (λex) of 367 nm for 2-4 and 380 nm for 5 and 6). The magnetic properties of the complexes revealed magnetically uncoupled Ho3+ compounds with no field-induced, single-molecule magnet (SMMs)
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