529 research outputs found

    Local softness, softness dipole and polarizabilities of functional groups: application to the side chains of the twenty amino acids

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    The values of molecular polarizabilities and softnesses of the twenty amino acids were computed ab initio (MP2). By using the iterative Hirshfeld scheme to partition the molecular electronic properties, we demonstrate that the values of the softness of the side chain of the twenty amino acid are clustered in groups reflecting their biochemical classification, namely: aliphatic, basic, acidic, sulfur containing, and aromatic amino acids . The present findings are in agreement with previous results using different approximations and partitioning schemes [P. Senet and F. Aparicio, J. Chem. Phys. 126,145105 (2007)]. In addition, we show that the polarizability of the side chain of an amino acid depends mainly on its number of electrons (reflecting its size) and consequently cannot be used to cluster the amino acids in different biochemical groups, in contrast to the local softness. Our results also demonstrate that the global softness is not simply proportional to the global polarizability in disagreement with the intuition that "a softer moiety is also more polarizable". Amino acids with the same softness may have a polarizability differing by a factor as large as 1.7. This discrepancy can be understood from first principles as we show that the molecular polarizability depends on a "softness dipole vector" and not simply on the global softness

    Blunt Abdominal Trauma in a European Trauma Setting : Need for Complex or Non-Complex Skills in Emergency Laparotomy

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    Background and Aims: Blunt abdominal trauma can lead to substantial organ injury and hemorrhage necessitating open abdominal surgery. Currently, the trend in surgeon training is shifting away from general surgery and the surgical treatment of blunt abdominal trauma patients is often done by sub-specialized surgeons. The aim of this study was to identify what emergency procedures are needed after blunt abdominal trauma and whether they can be performed with the skill set of a general surgeon. Materials and Methods: The records of blunt abdominal trauma patients requiring emergency laparotomy (n = 100) over the period 2006-2016 (Helsinki University Hospital Trauma Registry) were reviewed. The organ injuries and the complexity of the procedures were evaluated. Results: A total of 89 patients (no need for complex skills, NCS) were treated with the skill set of general surgeons while 11 patients required complex skills. Complex skills patients were more severely injured (New Injury Severity Score 56.4 vs 35.9, p <0.001) and had a lower systolic blood pressure (mean: 89 vs 112, p = 0.044) and higher mean shock index (heart rate/systolic blood pressure: 1.43 vs 0.95, p = 0.012) on admission compared with NCS patients. The top three NCS procedures were splenectomy (n = 33), bowel repair (n = 31), and urinary bladder repair (n = 16). In patients requiring a complex procedure (CS), the bleeding site was the liver (n = 7) or a major blood vessel (n = 4). Conclusion: The majority of patients requiring emergency laparotomy can be managed with the skills of a general surgeon. Non-responder blunt abdominal trauma patients with positive ultrasound are highly likely to require complex skills. The future training of surgeons should concentrate on NCS procedures while at the same time recognizing those injuries requiring complex skills.Peer reviewe

    Enhanced optical properties of Tm<sup>3+</sup> in f co-doped lead germanate glasses for fibre device applications

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    The effect on structure and property of adding fluoride into Tm3+ doped lead-germanate glass was established and verified experimentally. It was found that up to 10 mol% of fluoride could be introduced into our original lead-germanate composition while retaining the high thermal stability ideal for fibre fabrication. Much improved spectroscopic features, namely increased fluorescent lifetimes from 3H4 and 3F4 levels in Tm3+ with increasing fluorine content, were observed. At the same time it was found that the radiative properties of Tm3+ were left unchanged by fluoride addition, indicating that reduced multiphonon relaxation was responsible for the increased fluorescent lifetimes. This was well explained and foreseen by our established structure-property relation in terms of adding fluorine to the glass. In conclusion, fluoro-germanate glass shows advantages over germanate glass in optical properties and over fluoride glass in chemical and mechanical properties for practical fiber device applications. [Presentation slides

    Occipital condyle fracture-A rare but severe injury in cranial fracture patients

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    We clarified occurrence, severity, and associated injuries of occipital condyle fractures (OCFs) in a cranial fracture population. Retrospective data of cranial fracture patients were analyzed. The outcome variable was presence of OCF in cranial fracture patients. Predictor variables were type of associated injury, Glasgow Coma Scale (GCS) value under 6, and death during hospital care. In addition, occurrence of OCF was assessed according to cranial fracture subtypes. Explanatory variables were age, sex, injury mechanism, involvement of alcohol, and high-energy injury. Treatment and outcome of OCFs were analyzed. Of 637 cranial fracture patients, 19 (3.0%) sustained an OCF, eight of whom had no other cranial fractures. In the multivariate adjusted model, increased risk for OCF was detected in patients with cervical injuries (OR 18.66, 95% CI 5.52, 63.12; p < 0.001) and facial fractures (OR 5.99, 95% CI 1.01, 35.45; p = 0.049). Patients with fractures not extending to the skull base were less likely to have OCF (OR 0.01, 95% CI 0.001, 0.25; p = 0.004), and fractures localized solely to the base of the skull offered a protective effect for OCF (OR 0.19, 95% CI 0.06, 0.58; p = 0.003). All OCFs were treated non-operatively with a cervical collar without complications. OCF patients typically sustain other severe injuries, particularly cervical injuries and facial fractures. Careful screening for associated injuries is therefore crucial when examining a patient with OCF. The classification scheme of Mueller et al. seems to be useful in guiding the treatment of OCFs, at least type 1 and 2 fractures. (C) 2021 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.Peer reviewe

    Empathy, engagement, entrainment: the interaction dynamics of aesthetic experience

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    A recent version of the view that aesthetic experience is based in empathy as inner imitation explains aesthetic experience as the automatic simulation of actions, emotions, and bodily sensations depicted in an artwork by motor neurons in the brain. Criticizing the simulation theory for committing to an erroneous concept of empathy and failing to distinguish regular from aesthetic experiences of art, I advance an alternative, dynamic approach and claim that aesthetic experience is enacted and skillful, based in the recognition of others’ experiences as distinct from one’s own. In combining insights from mainly psychology, phenomenology, and cognitive science, the dynamic approach aims to explain the emergence of aesthetic experience in terms of the reciprocal interaction between viewer and artwork. I argue that aesthetic experience emerges by participatory sense-making and revolves around movement as a means for creating meaning. While entrainment merely plays a preparatory part in this, aesthetic engagement constitutes the phenomenological side of coupling to an artwork and provides the context for exploration, and eventually for moving, seeing, and feeling with art. I submit that aesthetic experience emerges from bodily and emotional engagement with works of art via the complementary processes of the perception–action and motion–emotion loops. The former involves the embodied visual exploration of an artwork in physical space, and progressively structures and organizes visual experience by way of perceptual feedback from body movements made in response to the artwork. The latter concerns the movement qualities and shapes of implicit and explicit bodily responses to an artwork that cue emotion and thereby modulate over-all affect and attitude. The two processes cause the viewer to bodily and emotionally move with and be moved by individual works of art, and consequently to recognize another psychological orientation than her own, which explains how art can cause feelings of insight or awe and disclose aspects of life that are unfamiliar or novel to the viewer

    Increased Collagen-Linked Pentosidine Levels and Advanced Glycosylation End Products in Early Diabetic Nephropathy

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    RATIONALE: Advanced glycosylation end products (AGEs) may play an important role in the development of diabetic vascular sequelae. An AGE cross-link, pentosidine, is a sensitive and specific marker for tissue levels of AGEs. OBJECTIVES: To evaluate the role of AGEs in the development of diabetic nephropathy and retinopathy, we studied pentosidine levels and the clinical characteristics of 48 subjects with insulin-dependent diabetes mellitus. Diabetic nephropathy was classified as normal, microalbuminuria, or gross proteinuria, and retinopathy was graded as none, background, or proliferative. NEWLY OBSERVED FINDINGS: Significant elevation of pentosidine (P = 0.025) was found in subjects with microalbuminuria or gross proteinuria (73.03 +/- 9.47 vs 76.46 +/- 6.37 pmol/mg col) when compared with normal (56.96 +/- 3.26 pmol/mg col). Multivariate analysis to correct for age, duration of diabetes, and gender did not modify the results. Elevated pentosidine levels were also found in those with proliferative when compared with those with background retinopathy (75.86 +/- 5.66 vs 60.42 +/- 5.98 pmol/mg col) (P \u3c 0.05). CONCLUSIONS: Microalbuminuria is associated with elevated levels of pentosidine similar to those found in overt diabetic nephropathy suggesting that elevated AGE levels are already present during the earliest detectable phase of diabetic nephropathy

    11HDL-induced cardioprotection is independent of the HDL receptor, scavenger receptor B1

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    Purpose: High-density lipoproteins (HDL) are atheroprotective. New evidence shows that HDL has widespread actions, including protection against cardiac ischemia reperfusion injury (IRI). This cardioprotective role has been attributed to several constituents of the HDL particle, including apolipoprotein A1 (apoA1) the major protein constituent and sphingosine-1-phosphate (S1P). However, the exact mechanisms of HDL-induced cardioprotection are still unknown and are under intensive investigation. A particular unresolved question remains the specific role of the HDL receptor, Scavenger Receptor BI (SR-BI), in the heart. The latter mediates many of the intracellular effects of HDL. The aim of this study was to evaluate the specific role of SR-BI in the protective impact of HDL on the heart. Methods and Results: The effects of HDL on the heart was evaluated in vitro using rat cultured neonatal cardiomyocytes and ex vivo in mice using the isolated heart Langendorff model of IRI (global no flow ischemia 35min, reperfusion 60min). In this model, HDL (400μg/mL) was injected during the first 7min of reperfusion and infarct size was assessed by triphenyltetrazolium chloride (TTC) staining. The specific role of SR-BI was investigated in vitro using specific siRNA facilitated knockdown and ex vivo using SR-BI knockout (SR-BI KO) mice. We confirmed that SR-BI is expressed in the cardiomyocytes and that HDL binds specifically to these cells. Treatment of cardiomyocytes with HDL induced the activation of several prosurvival signalling proteins, including Akt, STAT3 and ERK1/2 and protected the cells against oxidative stress induced by doxorubicin. Although specific binding of HDL was significantly reduced in SR-BI knockdown cardiomyocytes, activation of the prosurvival pathways was not affected. Similarly, SR-BI knockdown did not reduce the in vitro protective influence of HDL against oxidative stress induced by doxorubicin. Ex vivo, IRI induced an infarct size of 17.3±0.6% in isolated hearts of wildtype mice. HDL treatment during the first phase of reperfusion significantly reduced the infarct size by approximately 35% (p<0.05). This protective effect induced by HDL is maintained in SR-BI KO mice (40% of infarct size reduction (p<0.05) compared to non-treated SR-BI-KO mice). Conclusion: This is the first time that the specific role of SR-BI in the impact of HDL on the heart is investigated. Our results do not support a role for the HDL receptor SR-BI in the protective influence of HDL. Further investigations will be required to elucidate the exact mechanisms of HDL-induced cardioprotectio

    1.9µm operation of a Tm:Lead germanate glass waveguide laser

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    We report what we believe to be the first planar-technology waveguide laser in the 2-µm region. Laser operation of the 3H4 to 3H6 transition of Tm3+ ions in a lead germanate glass host has been observed in an ion-implanted planar waveguide

    Cervical spine injuries in facial fracture patients - injury mechanism and fracture type matter

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    Evidence supports the notion that craniofacial fractures are significant predictors of cervical spine injuries (CSIs), but some debate remains on the injury mechanism of co-existing CSIs in craniofacial fractures and the relationship between CSI and specific facial fractures. In this retrospective study, we aim to assess the incidence rates of specific facial fracture types as well as other important variables and their relationship with CSIs. The primary outcome variable, CSI, and several predictor variables, including facial fracture type, were evaluated with logistic regression analyses. Of 2919 patients, the total CSI incidence rate was 3.0%. Rates of CSI in patients with isolated mandibular fractures (OR 0.26 CI 0.10, 0.63; p = 0.006) were lower than those previously reported, whereas isolated nasal fractures were strongly associated with CSI (OR 2.67 CI 1.36, 5.22; p = 0.004). Patients with concomitant cranial injuries were twice as likely to have CSI (OR 2.00, CI 1.22, 3.27; p = 0.006). Even though there is a strong occurrence rate of CSIs in patients with cranial injuries, clinicians should be aware that patients presenting with isolated facial fractures are at significant risk for sustaining CSIs also. (C) 2021 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.Peer reviewe

    Tangled Nature: A model of emergent structure and temporal mode among co-evolving agents

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    Understanding systems level behaviour of many interacting agents is challenging in various ways, here we'll focus on the how the interaction between components can lead to hierarchical structures with different types of dynamics, or causations, at different levels. We use the Tangled Nature model to discuss the co-evolutionary aspects connecting the microscopic level of the individual to the macroscopic systems level. At the microscopic level the individual agent may undergo evolutionary changes due to mutations of strategies. The micro-dynamics always run at a constant rate. Nevertheless, the system's level dynamics exhibit a completely different type of intermittent abrupt dynamics where major upheavals keep throwing the system between meta-stable configurations. These dramatic transitions are described by a log-Poisson time statistics. The long time effect is a collectively adapted of the ecological network. We discuss the ecological and macroevolutionary consequences of the adaptive dynamics and briefly describe work using the Tangled Nature framework to analyse problems in economics, sociology, innovation and sustainabilityComment: Invited contribution to Focus on Complexity in European Journal of Physics. 25 page, 1 figur
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