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BACKGROUND: Thoracoabdominal aortic aneurysms (TAAAs) are a life‐threatening condition which remain difficult to treat. Endovascular and open surgical repair (OSR) provide treatment options for patients, however, due to the lack of clinical trials comparing these, the optimum treatment option is unknown. OBJECTIVES: To assess the effectiveness and safety of endovascular repair versus conventional OSR for the treatment of TAAAs. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 26 April 2021. We also searched references of relevant articles retrieved from the electronic search for additional citations. SELECTION CRITERIA: We considered all published and unpublished randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing endovascular repair to OSR for TAAAs for inclusion in the review. The main outcomes of interest were prevention of aneurysm rupture (participants without aneurysm rupture up to 5 years from intervention), aneurysm‐related mortality (30 days and 12 months), all‐cause mortality, spinal cord ischaemia (paraplegia, paraparesis), visceral arterial branch compromise causing mesenteric ischaemia or renal failure, and rate of reintervention. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts identified from the searches to identify those that met the inclusion criteria. We planned to undertake data collection, risk of bias assessment, and analysis in accordance with Cochrane recommendations. We planned to assess the certainty of the evidence using GRADE. MAIN RESULTS: No RCTs or CCTs met the inclusion criteria for this review. AUTHORS' CONCLUSIONS: Due to the lack of RCTs or CCTs, we were unable to determine the safety and effectiveness of endovascular compared to OSR in patients with TAAAs and are unable to provide any evidence on the optimal surgical intervention for this cohort of patients. High‐quality RCTs or CCTs addressing this objective are necessary, however conducting such studies will be logistically and ethically challenging for this life‐threatening disease.

BACKGROUND: Type B aortic dissection can lead to serious and life‐threatening complications such as aortic rupture, stroke, renal failure, and paraplegia, all of which require intervention. Traditionally, these complications have been treated with open surgery. Recently however, endovascular repair has been proposed as an alternative. OBJECTIVES: To assess the effectiveness and safety of thoracic aortic endovascular repair versus open surgical repair for treatment of complicated chronic Type B aortic dissection (CBAD). SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, and AMED databases, as well as the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers, to 2 August 2021. We searched references of relevant articles retrieved through the electronic search for additional citations. SELECTION CRITERIA: We considered all randomised controlled trials (RCTs) and controlled clinical trials (CCTs) assessing the effects of thoracic aortic endovascular repair (TEVAR) versus open surgical repair (OSR) for treatment of complicated chronic Type B aortic dissection (CBAD). Outcomes of interest were mortality (all‐cause, dissection‐related), neurological sequelae (stroke, spinal cord ischaemia/paresis‐paralysis, vertebral insufficiency), morphological outcomes (false lumen thrombosis, progression of dissection, aortic diameters), acute renal failure, ischaemic symptoms (visceral ischaemia, limb ischaemia), re‐intervention, and health‐related quality of life. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts identified by the searches to identify those that met the inclusion criteria. From title and abstract screening, we did not identify any trials (RCTs or CCTs) that required full‐text assessment. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions. We planned to assess the certainty of evidence using GRADE. MAIN RESULTS: We did not identify any trials (RCTs or CCTs) that met the inclusion criteria for this review. AUTHORS' CONCLUSIONS: Due to lack of RCTs or CCTs investigating the effectiveness and safety of TEVAR compared to OSR for patients with complicated CBAD, we are unable to provide any evidence to inform decision‐making on the optimal intervention for these patients. High‐quality RCTs or CCTs addressing this objective are necessary. However, conducting such studies will be challenging for this life‐threatening disease.

Advancement of subject-specific in-silico medicine requires new imaging protocols tailored to specific anatomical features, paired with new constitutive model development based on structure/function relationships. In this study we develop a new dual-VENC 4D Flow MRI protocol that provides unprecedented spatial and temporal resolution of in-vivo aortic deformation. All previous dual-VENC 4D Flow MRI studies in the literature focus on an isolated segment of the aorta, which fail to capture the full spectrum of aortic heterogeneity that exists along the vessel length. The imaging protocol developed provides high sensitivity to all blood flow velocities throughout the entire cardiac cycle, overcoming the challenge of accurately measuring the highly unsteady non-uniform flow field in the aorta. Cross sectional area change, volumetric flow rate, and compliance are observed to decrease with distance from the heart, while pulse wave velocity is observed to increase. A non-linear aortic lumen pressure-area relationship is observed throughout the aorta, such that a high vessel compliance occurs during diastole, and a low vessel compliance occurs during systole. This suggests that a single value of compliance may not accurately represent vessel behaviour during a cardiac cycle in-vivo. This high-resolution MRI data provides key information on the spatial variation in non-linear aortic compliance which can significantly advance the state-of-the-art of in-silico diagnostic techniques for the human aorta.

This paper, the second of two parts, presents a novel subject-specific in-silico framework in which we uncover the relationship between the spatially varying constituents of the aorta and the non-linear compliance of the vessel during the cardiac cycle uncovered in Part I. In Part II a novel microstructurally motivated constitutive model is developed, and simulations reveal that internal vessel contractility, due to pre-stretched elastin and actively generated smooth muscle stress, must be incorporated, along with collagen strain stiffening, in order to accurately predict the non-linear pressure-area relationship observed in-vivo. Modelling of elastin and smooth muscle contractility allows for the identification of the reference vessel configuration at zero-lumen pressure, in addition to accurately predicting high- and low-compliance regimes under a physiological range of pressures. This modelling approach is also shown to capture the key features of elastin and SMC knockout experiments. The volume fractions of the constituent components of the aortic material model were computed so that the in-silico pressure-area curves accurately predict the corresponding MRI data at each location. Simulations reveal that collagen and smooth muscle volume fractions increase distally, while elastin volume fraction decreases distally, consistent with reported histological data. Furthermore, the strain at which collagen transitions from low to high stiffness is lower in the abdominal aorta, again supporting the histological finding that collagen waviness is lower in this distally. The analyses presented in this paper provides new insights into the heterogeneous structure-function relationship that underlies aortic biomechanics. This novel subject-specific MRI/FEA methodology provides a foundation for personalised in-silico clinical analysis and tailored aortic device development.

Although the residues of official segregation are widespread, affirmative action continues to meet resistance in both official and everyday life, even in such recent Supreme Court decisions as Grutter v Bollinger (539 U.S. 306). This is due in part to a governing ontology that draws the line between individual and collective. But there are other possibilities for conceiving the social, and I offer one here in a theory of affirmative action that is developed through close examination of sharing and promising as elemental qualities of equitable communal life. The nature and value of these actions are demonstrated in narrative formulations of fairness as exemplified in triage and the situation at the end of slavery; of the difference between equality and equity and how justice depends on their conjunction; and finally of theorizing how these may come together in the permutable, opaque, yet resilient interdependence of person and community that represents most deeply the Greek idea of two in one, that is, of one two, not two ones. In these respects the paper is successful insofar as it discloses the kinds of reasoning that underlie both resistance and commitment to affirmative action.

This study was conducted to assess the mechanical characteristics of dilated polytetraflouroethylene (PTFE) for use in transluminally placed endovascular grafts (TPEGs). Ten-centimeter lengths of 3- and 4-mm thinwalled PTFE were dilated to 8, 10, 12, and 15 mm diameters (3 mm) and 10-, 14-, 16-, and 20-mm diameters (4 mm), respectively (n = 6 for each size). The dilated PTFE segments were evaluated for leakage, further dilation, structural changes (with electron microscopy), and changes in wall thickness occurring after 24 hours of perfusion at pressures of 300-350 mmHg. Both 3- and 4-mm thinwalled PTFE could be dilated to five times their initial diameter before rupture occurred. Three-millimeter grafts dilated to 12- and 4-mm grafts dilated to 14 mm remained resistant to leakage at perfusion pressures up to 350 mmHg. When 3-mm grafts were dilated to 15 mm, the PTFE leaked saline at a rate of 20.3 +/- 9.3 cc per hour at 300 mmHg. pressure. Four-millimeter grafts dilated to 16- and 20-mm diameters leaked saline at 8.4 +/- 7.8 and 52.8 +/- 22 cc per minute, respectively, at the same pressure. No grafts were found to increase in diameter after 24 hours of pressure perfusion. Electron microscopy revealed that PTFE node size was significantly smaller in dilated grafts than in undilated grafts, but there was no significant change in internodal distance. This data suggests that thinwalled PTFE can be dilated to large diameters and retain sufficient strength to resist supraphysiologic pressures. Long-term studies are needed to determine the late structural integrity of dilated PTFE.

Certain familiar theoretic claims of both popular and academic postmodernism are examined for their implications as to the necessary and desirable limits of social life. Taken to the end, these claims promote errancy as a means of freeing conduct from the constraints of foundation. But this kind of freedom, one which treats all limitation as pernicious, generates social action that is mechanical, scattered, and without substance—it is a pyrrhic emancipation which trades content for self-sufficiency and thus constitutes an empty life of unhappy social dispersion. And yet an opportunity does remain to address the way a limit can also be inspiring if we think through how interpretation, a limit which is itself limited, invites nevertheless what Derrida glossed as “joyous affirmation.” Interpretation, though imperfect, offers powers that are genuine and enjoyable because these powers supply life with content and thus with the vitalizing collective and individual possibility of conduct which is affirmative (and disaffirmative). Perhaps it could even be said that interpretation emancipates us from the emptiness of pure freedom.

Gatifloxacin, until recently one of the most commonly prescribed antibiotics, has been shown to produce hypoglycemia.To further examine the effects of Gatifloxicin (G) on blood glucose (BS), we conducted a retrospective chart review on 264 inpatients, examining for both hypoglycemia and hyperglycemia, comparing G with another quinolone, Ciproflaxin (C), and nonquinolone, Ceftriaxone (R).We found that of 292 patient encounters, 28 hypoglycemia and 48 hyperglycemic events occurred. Patients given G were 5 times as likely to become hypoglycemic as C (P0.01) and 9 times as likely as those given R (P0.02). Patients given G were 5.6 times more likely to develop hypoglycemia (P0.001) than the combined group, R+C. Conversely, patients treated with G were 3.8 times as likely to become hyperglycemic as those give C (P0.01) and 9.8 times as those given R (P0.01). With C and R combined, those given G were 5.2 times as likely to develop hyperglycemia (P0.01). Looking at patient encounters where G was given, we found that having preexisting diabetes mellitus (DM) was positively associated with hypoglycemia (21/144, P0.001). Steroid use (P0.05) and being in the ICU (P0.01) were also positively associated with hyperglycemia (38/144, P0.01).In summary, G was clearly associated with both hypoglycemia and hyperglycemia compared with C and R. The risk of hyperglycemia increased in the presence of DM, steroid use, and "sick enough" to be in the intensive care unit.

explains in his Preface, he, as a former student of Schutz's, took on the task of completing this book. The assumption shared by Luckmann and Schutz's widow was that this work would be of considerable use to students of Schutz and indispensable to specialists in his thought. After fifteen years, the first part of the Structuren der Lebenswelt now appears (translated from the German, but apparently published before the German edition), containing the first four chapters of the complete book. The second volume, provisionally heralded to appear within a year, will contain the last two chapters, and will also reproduce Schutz's original plans, working papers and manuscripts. Given its relatively limited aim, that is a more systematic presentation of Schutz's ideas than was available in I959, the book might now be thought unnecessary for all but the specialists. In the intervening years, the scattered articles have been collected together into three volumes, and these will be by no means superseded in content by the new book, since Luckmann states he has found nothing in the manuscripts concerning the methodological implications for the social sciences which go beyond already published and quite well-known articles such as 'Commonsense and Scientific Interpretation of Human Action', and therefore is omitting the chapter on these questions from the plan of this new book. For the general student, then, whose reading of Schutz must be limited by constraints of time, The Structures of the Life-World may prove irrelevant. As for the specialists, Luckmann has provided them with their infinite task. Thesis-writers will now try to solve the problem which Luckmann himself claims not to be able to solve, namely which ideas are Schutz's and which Luckmann's, a problem in many ways irrelevant to the growth of human knowledge, but one which will inevitably be asked in conditions where ideas are treated as a form of private property. A short review does not allow detailed analysis of such a complex work. Those sections of this volume which are worth a trip are the section on relevance in Ghapter 3, which is a much clearer presentation than that in the larger relevance manuscript published by Richard M. Zaner under the title Re0!ections on the Problem of Relevance, though the problems treated are not identical, and Chapter 4, entitled 'Knowledge and Society', which is where Luckmann himself has most had to expand on Schutz's notes. ;Norman Stockman King's CMollege, Aberdeen