Extreme points of the set of density matrices with positive partial transpose

We present a necessary and sufficient condition for a finite dimensional density matrix to be an extreme point of the convex set of density matrices with positive partial transpose with respect to a subsystem. We also give an algorithm for finding such extreme points and illustrate this by some examples.Comment: 4 pages, 2 figure

Maternal smoking during pregnancy and scholastic achievement in childhood: evidence from the LIFECOURSE cohort study.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesResearch on the impact of maternal smoking during pregnancy (MSDP) on scholastic achievement in the offspring has shown conflicting findings. The objective of this study was to assess the impact of MSDP on scholastic achievement in a birth cohort of children in 4th, 7th and 10th grades.We analysed data from the LIFECOURSE study, a cohort study of risk and protective factors in all children born in Reykjavik, Iceland, in the year 2000 (N = 1151, girls = 49.3%). Retrospective registry data for 2014-2015 were merged with prospective survey data that were collected in April 2016. Data on MSDP were assessed during regular antenatal visits at the end of the first trimester. Standardized academic achievement scores were obtained from official school transcripts. Data were analysed using OLS regressions that were entered in three hierarchical blocks.Children of mothers who smoked tobacco during the first trimester consistently revealed between 5% and 7% lower scores on standardized academic achievement in 4th, 7th and 10th grade (∼6-8 points on a normally distributed 120 point scale) than those of mothers who had not smoked tobacco during this period (P < 0.05). These findings held after controlling for several factors associated with the time of birth (e.g. birth weight, maternal age at birth, birth order, parental cohabitation and household income), as well as the year of scholastic assessment (parental cohabitation, household income and parental education).Maternal smoking during pregnancy was negatively related to scholastic achievement in the offspring during 4th, 7th and 10th grade.European Research Counci

Final Report of the Nuclear Propulsion for Merchant Ships I (NuProShip I) project

This report contains the results of two years of research (2023 and 2024) performed under the context of Nuclear Propulsion for Merchant Ships (NuProShip) I, funded by the Research Council of Norway. The successor project, NuProShip II, is well underway as of January 2025. Starting from the nuclear reactor core and working ourselves outwards to the reactor systems, waste handling, ship systems, ship design, crew and more, we have performed a number or research tasks as presented in this report. Since we started at the nuclear reactor core, based on the idea that we need the right nuclear technology before anything else, the report is dominated by the large amount of work done to select the best possible reactor technologies. We have selected reactors among all the known reactor concepts by yearend 2022, some 80+ of them, as detailed in Chapter 2. First, we applied a set of 11 exclusion criteria that were very clearcut, after which we had about 8 possible reactor concepts left. These 8 reactor concepts were subsequently subjected to another 26 criteria for further selection. The end result is three reactor concepts; 1) molten-salt reactor using TRISO fuel designed by Kairos Power (USA), 2) a helium gas-cooled reactor using TRISO fuels designed by Ultra Safe Nuclear Corporation (USA), and 3) a lead-cooled reactor designed by Blykalla (Sweden). By selecting these reactor concepts and studying their intrinsic properties, we realized that one single reactor technology cannot address the entire shipping industry. In NuProShip II, we will continue working on this. Preliminary results, however, indicate that the MSR will work best with large ships that need steam turbines. The helium gas-cooled reactor will work best with ships that need electric propulsion system. The lead-cooled reactor will work best in situations where the load is more stable situations such as baseload operation. Once these overall findings were clear, the two other work packages – discussed in Chapters 3 and 4 – could start working in earnest. In Chapter 3 we find a lot of insights from a ship design and class society perspective. This is a complex area, and to gain a complete overview of it is difficult, which will go on well into NuProShip II as well. This is evident for the HAZID overview for which many issues are still not solved. However, we have started to get a very good overview of the class requirements and international regulations. Most of the results presented here must nonetheless be viewed as preliminary. The challenge is to go from the high, conceptual level down to a concrete ship, such as the Cadiz Knutsen owned by Knutsen OAS. This ship has served as a mental reminder of what we are working on, and the ship is also used as a practical working case. The same can be said about the work presented in Chapter 4. Researching what skills the crew needs, what qualifications they must have and therefore develop an education and training system is also complex work. The fact is that none of the reactor technologies we have identified have ever been used at sea. The closest is the lead-bismuth cooled reactor used unsuccessfully in the Russian navy. One finding that seems to be very clear is that some remote monitoring/operations of ships must be implemented. Naval ships are today largely self-contained, and for that reason they have a reactor crew that is too large for commercial chips of any sort due to both the availability of crew but ultimately also costs. Therefore, remote monitoring/operations is seen as key enabler. Obviously, all the topics discussed in Chapter 3 are also extended well into NuProShip II. The report does not contain much information about costs. The reason is that it is basically too early for making any trustworthy estimates. However, this will be adressed in NuProShip II.publishedVersio

Can local application of Tranexamic acid reduce post-coronary bypass surgery blood loss? A randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Diffuse microvascular bleeding remains a common problem after cardiac procedures.</p> <p>Systemic use of antifibrinolytic reduces the postoperative blood loss.</p> <p>The purpose of this study was to examine the effectiveness of local application of tranexamic acid to reduce blood loss after coronary artery bypass grafting (CABG).</p> <p>Methods</p> <p>Thirty eight patients scheduled for primary isolated coronary artery bypass grafting were included in this double blind, prospective, randomized, placebo controlled study.</p> <p>Tranexamic acid (TA) group (19 patients) received 1 gram of TA diluted in 100 ml normal saline. Placebo group (19 patients) received 100 ml of normal saline only. The solution was purred in the pericardial and mediastinal cavities.</p> <p>Results</p> <p>Both groups were comparable in their baseline demographic and surgical characteristics. During the first 24 hours post-operatively, cumulative blood loss was significantly less in TA group (median of 626 ml) compared to Placebo group (median of 1040 ml) (P = 0.04). There was no significant difference in the post-op Packed RBCs transfusion between both groups (median of one unit in each) (P = 0.82). Significant less platelets transfusion required in TA group (median zero unit) than in placebo group (median 2 units) (P = 0.03). Apart from re-exploration for excessive surgical bleeding in one patient in TA group, no difference was found in morbidity or mortality between both groups.</p> <p>Conclusion</p> <p>Topical application of tranexamic acid in patients undergoing primary coronary artery bypass grafting led to a significant reduction in postoperative blood loss without adding extra risk to the patient.</p

The estimation of oxidative stress markers and apoptosis in right atrium auricles cardiomyocytes of patients undergoing surgical heart revascularisation with the use of warm blood cardioplegia.

Oxidative stress markers and apoptosis were estimated during elective surgical heart revascularization. Eight patients with good ejection fraction underwent coronary artery bypass grafting (CABG) with the use of warm blood cardioplegia. Two right atrium auricle biopsy specimens were collected before and after the operation. Specimens underwent immunocytochemical analysis of mitochondrial manganese superoxide dismutase (MnSOD) expression and apoptosis estimation by the TUNEL method. Ultrastructure analysis under electron microscope was made. Satisfactory results of the operation were obtained. After CABG the MnSOD expression increase in sections of auricles was observed through the increase of stain intensity and the percentage of cells with positive stain (from 30 to 80%). The apoptotic cells percentage remained at approximately the same level. Under the electron microscope insignificant pathological changes were observed. On this basis one may assume that in the case of cardiosurgical procedures with short aorta cross-clamping time and low operation risk level the application of cardioplegia sufficiently prevents reactive oxygen forms (ROF) cytotoxic activity although it does not inhibit the expression of oxidative stress (OS) markers. In our opinion the method of examining right atrium sections is safe and provides results comparable with other publications. It may also be a voice in the discussion on new methods of heart protection during cardiac surgery procedures

Strategies to prevent intraoperative lung injury during cardiopulmonary bypass

During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB), hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved