Duality and self-reflexive torsion-free abelian groups

AbstractWe characterize the torsion-free abelian groups G of finite rank such that Hom(−, G) defines a rank preserving duality on the category of End(G)-submodules of finite sums of copies of G. Our results provide a maximal extension of Warfield's duality result for torsion-free groups of finite rank. In order to obtain our extension, we study the torsion-free abelian groups G for which G ≅nat Hom(Hom(G, G), G)

Unique decompositions into ideals for Noetherian domains

AbstractA commutative ring R has the unique decompositions into ideals (UDI) property if, for any module L that decomposes into a finite direct sum of ideals, the decomposition of L into ideals is unique apart from the order of the ideals. We characterize the UDI Noetherian integral domains

Aminosäuren – Leitlinie Parenterale Ernährung, Kapitel 4

Protein catabolism should be reduced and protein synthesis promoted with parenteral nutrion (PN). Amino acid (AA) solutions should always be infused with PN. Standard AA solutions are generally used, whereas specially adapted AA solutions may be required in certain conditions such as severe disorders of AA utilisation or in inborn errors of AA metabolism. An AA intake of 0.8 g/kg/day is generally recommended for adult patients with a normal metabolism, which may be increased to 1.2–1.5 g/kg/day, or to 2.0 or 2.5 g/kg/day in exceptional cases. Sufficient non-nitrogen energy sources should be added in order to assure adequate utilisation of AA. A nitrogen calorie ratio of 1:130 to 1:170 (g N/kcal) or 1:21 to 1:27 (g AA/kcal) is recommended under normal metabolic conditions. In critically ill patients glutamine should be administered parenterally if indicated in the form of peptides, for example 0.3–0.4 g glutamine dipeptide/kg body weight/day (=0.2–0.26 g glutamine/kg body weight/day). No recommendation can be made for glutamine supplementation in PN for patients with acute pancreatitis or after bone marrow transplantation (BMT), and in newborns. The application of arginine is currently not warranted as a supplement in PN in adults. N-acetyl AA are only of limited use as alternative AA sources. There is currently no indication for use of AA solutions with an increased content of glycine, branched-chain AAs (BCAA) and ornithine-α-ketoglutarate (OKG) in all patients receiving PN. AA solutions with an increased proportion of BCAA are recommended in the treatment of hepatic encephalopathy (III–IV).Ein Proteinkatabolismus soll bei parenteraler Ernährung (PE) vermindert und anabole Stoffwechselprozesse gefördert werden. Standard-Aminosäure (AS)-Lösungen werden empfohlen, falls nicht in Sondersituationen z. B. bei schweren AS-Verwertungsstörungen oder bei angeborenen Stoffwechselstörungen spezifisch adaptierte AS-Lösungen eingesetzt werden müssen. Für erwachsene Patienten in ausgeglichenem Stoffwechselzustand wird eine AS-Zufuhr von 0,8 g/kg/Tag empfohlen, die auf 1,2–1,5 g/kg/Tag oder in Ausnahmefällen auch auf 2,0–2,5 g/kg/Tag gesteigert werden kann. Zur Gewährleistung einer angemessenen Utilisation von AS sollten ausreichend Nicht-Stickstoff-Energieträger zugegeben werden. Das angestrebte Verhältnis zwischen Stickstoff- und Energiezufuhr (Stickstoff-Kalorien-Verhältnis) sollte unter Normalbedingungen 1:100–1:130 (g N:kcal) bzw. 1:16–1:21 (g AS:kcal) betragen. Glutamin sollte parenteral bei kritisch Kranken, sofern indiziert, in Form von Peptiden verabreicht werden, wie z.B. 0,3–0,4 g Glutamin-Dipepetid/kg KG/Tag (entsprechend 0,2–0,26 g Glutamin/kg KG/Tag). Für Patienten mit akuter Pankreatitis, nach Knochenmarkstransplantation sowie für Neugeborene kann derzeit keine Empfehlung für eine Glutaminsupplementierung mit der PE ausgesprochen werden. Der Einsatz von Arginin als Supplement in der PE beim Erwachsenen ist derzeit nicht gerechtfertigt. Den N-azetylierten AS kommen als alternative Aminosäurenquellen zur Zeit nur eine begrenzte Bedeutung zu. Für eine generelle Verwendung von AS-Lösungen mit einem erhöhten Gehalt von Glyzin und verzweigtkettigten AS (VKAS) wie auch für Ornithin-α-Ketoglutarat (OKG) besteht keine gesicherte Indikation. Die Wirksamkeit von AS-Lösungen mit erhöhtem Anteil an VKAS in der Behandlung der hepatischen Enzephalopathie (III–IV) wird empfohlen

Studies on the flight medical aspects of the German Lufthansa non-stop route from Frankfurt to Rio de Janeiro, part 1

The problem of crew size for regularly scheduled flights between Frankfurt and Rio de Janeiro is discussed. Factors affecting crew performance are examined, comparisons are drawn to regulations of other countries and crew questionnaires and tests are presented

Effects of nicotine abstinence and menstrual phase on task performance

Both menstrual phase and nicotine have been shown to affect task performance. Though conflicting results have been reported, at least one well-controlled study has demonstrated that women at midluteal phase show superior performance on speech articulation and speeded motor coordination tests, but poorer performance on perceptual-spatial tests, than during menses. Smokers have demonstrated superior performance on numerous tasks following nicotine than following placebo. To explore the separate and combined influence of these factors, we studied 13 regularly-menstruating smokers using a two (smoking vs. 12 hours' abstinence) by two (menstrual vs. midluteal phase) factorial design. During each session, subjects completed a test battery including two speeded motor coordination tasks, a computerized reaction time test, and the Stroop (1935) color/word test. Subjects completed the Stroop color and color-word tasks significantly faster after ad lib smoking than after overnight abstinence. No other significant differences emerged. Our findings replicate, in an all-female sample, previous reports that speed of cognitive processing is reduced by nicotine abstinence (or enhanced by nicotine administration). Our failure to observe menstrual cycle effects raises the possibility that the anti-estrogenic effects of smoking may attenuate phase differences in performance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31479/1/0000401.pd

Amino acids – Guidelines on Parenteral Nutrition, Chapter 4

Protein catabolism should be reduced and protein synthesis promoted with parenteral nutrion (PN). Amino acid (AA) solutions should always be infused with PN. Standard AA solutions are generally used, whereas specially adapted AA solutions may be required in certain conditions such as severe disorders of AA utilisation or in inborn errors of AA metabolism. An AA intake of 0.8 g/kg/day is generally recommended for adult patients with a normal metabolism, which may be increased to 1.2–1.5 g/kg/day, or to 2.0 or 2.5 g/kg/day in exceptional cases. Sufficient non-nitrogen energy sources should be added in order to assure adequate utilisation of AA. A nitrogen calorie ratio of 1:130 to 1:170 (g N/kcal) or 1:21 to 1:27 (g AA/kcal) is recommended under normal metabolic conditions. In critically ill patients glutamine should be administered parenterally if indicated in the form of peptides, for example 0.3–0.4 g glutamine dipeptide/kg body weight/day (=0.2–0.26 g glutamine/kg body weight/day). No recommendation can be made for glutamine supplementation in PN for patients with acute pancreatitis or after bone marrow transplantation (BMT), and in newborns. The application of arginine is currently not warranted as a supplement in PN in adults. N-acetyl AA are only of limited use as alternative AA sources. There is currently no indication for use of AA solutions with an increased content of glycine, branched-chain AAs (BCAA) and ornithine-α-ketoglutarate (OKG) in all patients receiving PN. AA solutions with an increased proportion of BCAA are recommended in the treatment of hepatic encephalopathy (III–IV)

Glutamine and glutathione at ICU admission in relation to outcome

Glutamine depletion is demonstrated to be an independent predictor of hospital mortality in ICU (intensive care unit) patients. Today glutamine supplementation is recommended to ICU patients on parenteral nutrition. In addition to glutamine, glutathione may be a limiting factor in ICU patients with MOF (multiple organ failure). To study the prevalence of glutamine and glutathione depletion an observational study was performed. The results were analysed in relation to mortality and the conventional predictors of mortality outcome, APACHE II (Acute Physiology and Chronic Health Evaluation II) and SOFA (Sequential Organ Failure Assessment). Consecutive patients admitted to the ICU at Karolinska University Hospital Huddinge were studied. Patient admission scoring of APACHE II and SOFA were registered as well as mortality up to 6 months. Plasma glutamine concentration and whole blood glutathione status at admittance were analysed. The admission plasma glutamine concentrations were totally independent of the conventional risk scoring at admittance, and a subnormal concentration was an independent predictor of mortality. In addition, glutathione redox status was also an independent mortality predictor, but here a normal ratio was the risk factor. In both cases the mortality risk was mainly confined to the post-ICU period. A low plasma concentration of glutamine at ICU admission is an independent risk factor for post-ICU mortality. The possible benefit of extending glutamine supplementation post-ICU should be evaluated prospectively

Pragmatic approach to nutrition in the ICU: Expert opinion regarding which calorie protein target

BACKGROUND & AIMS:Since the publications of the ESPEN guidelines on enteral and parenteral nutrition in ICU, numerous studies have added information to assist the nutritional management of critically ill patients regarding the recognition of the right population to feed, the energy-protein targeting, the route and the timing to start. METHODS: We reviewed and discussed the literature related to nutrition in the ICU from 2006 until October 2013. RESULTS: To identify safe, minimal and maximal amounts for the different nutrients and at the different stages of the acute illness is necessary. These amounts might be specific for different phases in the time course of the patient's illness. The best approach is to target the energy goal defined by indirect calorimetry. High protein intake (1.5 g/kg/d) is recommended during the early phase of the ICU stay, regardless of the simultaneous calorie intake. This recommendation can reduce catabolism. Later on, high protein intake remains recommended, likely combined with a sufficient amount of energy to avoid proteolysis. CONCLUSIONS: Pragmatic recommendations are proposed to practically optimize nutritional therapy based on recent publications. However, on some issues, there is insufficient evidence to make expert recommendations