Decoupling Inflation From the String Scale

When Inflation is embedded in a fundamental theory, such as string theory, it typically begins when the Universe is already substantially larger than the fundamental scale [such as the one defined by the string length scale]. This is naturally explained by postulating a pre-inflationary era, during which the size of the Universe grew from the fundamental scale to the initial inflationary scale. The problem then arises of maintaining the [presumed] initial spatial homogeneity throughout this era, so that, when it terminates, Inflation is able to begin in its potential-dominated state. Linde has proposed that a spacetime with compact negatively curved spatial sections can achieve this, by means of chaotic mixing. Such a compactification will however lead to a Casimir energy, which can lead to effects that defeat the purpose unless the coupling to gravity is suppressed. We estimate the value of this coupling required by the proposal, and use it to show that the pre-inflationary spacetime is stable, despite the violation of the Null Energy Condition entailed by the Casimir energy.Comment: 24 pages, 5 eps figures, references added, stylistic changes, version to appear in Classical and Quantum Gravit

Effects of leucine supplemented diet on intestinal absorption in tumor bearing pregnant rats

BACKGROUND: It is known that amino acid oxidation is increased in tumor-bearing rat muscles and that leucine is an important ketogenic amino acid that provides energy to the skeletal muscle. METHODS: To evaluate the effects of a leucine supplemented diet on the intestinal absorption alterations produced by Walker 256, growing pregnant rats were distributed into six groups. Three pregnant groups received a normal protein diet (18% protein): pregnant (N), tumor-bearing (WN), pair-fed rats (Np). Three other pregnant groups were fed a diet supplemented with 3% leucine (15% protein plus 3% leucine): leucine (L), tumor-bearing (WL) and pair-fed with leucine (Lp). Non pregnant rats (C), which received a normal protein diet, were used as a control group. After 20 days, the animals were submitted to intestinal perfusion to measure leucine, methionine and glucose absorption. RESULTS: Tumor-bearing pregnant rats showed impairment in food intake, body weight gain and muscle protein content, which were less accentuated in WL than in WN rats. These metabolic changes led to reduction in both fetal and tumor development. Leucine absorption slightly increased in WN group. In spite of having a significant decrease in leucine and methionine absorption compared to L, the WL group has shown a higher absorption rate of methionine than WN group, probably due to the ingestion of the leucine supplemented diet inducing this amino acid uptake. Glucose absorption was reduced in both tumor-bearing groups. CONCLUSIONS: Leucine supplementation during pregnancy in tumor-bearing rats promoted high leucine absorption, increasing the availability of the amino acid for neoplasic cells and, mainly, for fetus and host utilization. This may have contributed to the better preservation of body weight gain, food intake and muscle protein observed in the supplemented rats in relation to the non-supplemented ones

Remarks on the Concept of Critique in Habermasian Thought

The main purpose of this paper is to examine the concept of critique in Habermasian thought. Given that the concept of critique is a central theoretical category in the work of the Frankfurt School, it comes as a surprise that little in the way of a systematic account which sheds light on the multifaceted meanings of the concept of critique in Habermas’s oeuvre can be found in the literature. This paper aims to fill this gap by exploring the various meanings that Habermas attributes to the concept of critique in 10 key thematic areas of his writings: (1) the public sphere, (2) knowledge, (3) language, (4) morality, (5) ethics, (6) evolution, (7) legitimation, (8) democracy, (9) religion, and (10) modernity. On the basis of a detailed analysis of Habermas’s multifaceted concerns with the nature and function of critique, the study seeks to demonstrate that the concept of critique can be considered not only as a constitutive element but also as a normative cornerstone of Habermasian thought. The paper draws to a close by reflecting on some of the limitations of Habermas’s conception of critique, arguing that in order to be truly critical in the Habermasian sense we need to turn the subject of critique into an object of critique

Apparent protein and energy digestibility of common and alternative feed ingredients by Atlantic cod, Gadus morhua (Linnaeus, 1758)

Studies were conducted with Atlantic cod, Gadus morhua (L.), to determine the apparent digestibility coefficients (ADCs) of protein and energy and the digestible energy (DE) content in feed ingredients widely available in Canada. We also tested the assumption of \u201cindependency\u201d used in digestibility studies. The feed ingredients included two fish meals (herring, anchovy), three crustacean by-product meals (whole krill, crab, shrimp), two animal by-product meals (poultry by-product, hydrolyzed feather), six oilseed meals (soybean, soy protein concentrate, soy protein isolate, canola, canola protein concentrate, flaxseed), two pulse meals (white lupin, pea protein concentrate) and two cereal grain meals (corn gluten, wheat gluten). Protein ADCs were high for wheat gluten meal (99.9%), soy protein concentrate (98.6%), soy protein isolate (97.4%), whole krill meal (96.3%), herring meal (93.3%), soybean meal (92.3%), anchovy meal (92.2%), pea protein concentrate (89.8%), white lupin meal (89.7%), crab meal (89.4%), canola protein concentrate (88.8%) and corn gluten meal (86.3%); mid-range for poultry by-product meal (80.2%) and canola meal (76.0%); and low for shrimp meal (66.7%), hydrolyzed feather meal (62.4%) and flaxseed meal (50.2\u201355.0%). Energy ADC was high for whole krill meal (96.3%), wheat gluten meal (95.4%), soy protein concentrate (94.9%), herring meal (92.8%), soy protein isolate (92.1%), soybean meal (88.1%) and anchovy meal (86.4%); mid-range for canola protein concentrate (83.3%), corn gluten meal (82.7%), crab meal (82.4%), pea protein concentrate (76.7%) and white lupin meal (75.3%); and low for poultry by-product meal (71.0%), canola meal (60.6%), hydrolyzed feather meal (58.9%), shrimp meal (41.4%) and flaxseed meal (21.2\u201337.4%). From the protein ADC data, results clearly showed that the basal diet and test feed ingredients were digested independently of one another in nearly all cases, the only exceptions being for those diets containing test ingredients of very high (> 99%, wheat gluten) or very low (< 67%, hydrolyzed feather and flaxseed) protein ADCs. In the case of DE, the basal diet and test feed ingredients were digested independently in all test diets without exception.Peer reviewed: YesNRC publication: Ye

E\ufb00ects of dietary protein and lipid levels and DP DE-1 ratio on growth, feed utilization and hepatosomatic index of juvenile haddock, Melanogrammus aegle\ufb01nus L.

Juvenile haddock, Melanogrammus aeglefinus L. (initial weight, 13.5 \ub1 0.1 g) were fed practical diets containing digestible protein to digestible energy (DP DE\u207b\ub9) ratios of 25-30 g DP MJ DE\u207b\ub9 as-fed using three protein levels (450, 500 and 550 g kg\u207b\ub9) each at two lipid levels (110 and 160 g kg\u207b\ub9) for 63 days. The results showed mean weight gain and feed conversion ratio were highest for diets containing 28.5 and 30.2 g DP MJ DE\u207b\ub9. DP DE\u207b\ub9 ratio had no significant effect on protein efficiency ratio except at the lowest level (24.7 g DP MJ DE\u207b\ub9) indicating a protein sparing effect of higher lipid when dietary protein is below the requirement. Haddock appears to preferentially use protein as the prime source of DE. DP DE\u207b\ub9 ratio had little effect on apparent digestibility (AD) of protein while AD of lipid was significantly affected. Significant differences in AD of energy and organic matter were found to be inversely related to the carbohydrate level of the diet. DP DE\u207b\ub9 ratios of 28.5 g DP MJ DE\u207b\ub9 or lower resulted in significantly higher hepatosomatic indexes. The highest whole-body nitrogen gains and energy retention efficiencies were achieved at 28.5 and 30.2 g DP MJ DE\u207b\ub9, whereas only slight differences in nitrogen retention efficiencies were observed. The highest levels of energy retained in the form of protein were achieved at 28.5 and 30.2 g DP MJ DE\u207b\ub9. The diet that provided the best growth, feed utilization and digestibility with minimal HSI contained 546 g kg\u207b\ub9 protein (513 g kg\u207b\ub9 DP), 114 g kg\u207b\ub9 lipid, 164 g kg\u207b\ub9 carbohydrate, 17.0 MJ kg DE\u207b\ub9 and a DP DE\u207b\ub9 ratio of 30.2 g DP MJ DE\u207b\ub9.Peer reviewed: YesNRC publication: Ye

Chemical composition and nutritional properties of freshwater and marine microalgal biomass cultured in photobioreactors

Proximate, amino acid and elemental composition, total phenolic content (TPC), and in vitro protein digestibility (IVPD) of microalgal biomass were determined. Microalgae contained low to moderate ash (5\u201317 %), moderate to high carbohydrate (18\u201346 %), crude protein (18\u201346 %), high crude lipid (12\u201348 %), and energy (19\u201327 MJ kg 121). Characteristic of microalgae, non-essential amino acids (AAs), aspartic and glutamic acids, were predominant (20\u201330 % of protein; 8\u201312 % of dry weight). Microalgae had favorable essential AA profiles with high essential amino acid (EAA) indices (0.9\u20131.2). Expressed as g EAA 100 g protein 121, Porphyridium aerugineum was rich in leucine (11.9), lysine (8.0), arginine (8.6), and tryptophan (3.3); Nannochloropsis granulata (A) in leucine (11.0), lysine (8.5), and tryptophan (2.8); Tetraselmis chuii and Botryococcus braunii in arginine (9.4 and 20.5, respectively); and Phaeodactylum tricornutum in lysine (6.4) and tryptophan (2.6). Mineral compositions (%) were calcium (0.1\u20133.0), magnesium (0.3\u20130.7), phosphorous (0.7\u20131.5), potassium (0.7\u20132.4), sodium (0.8\u20132.7), and sulfur (0.4\u20131.4), and trace element compositions (mg kg 121) were copper (18\u2013102), iron (1,395\u201311,101), manganese (45\u2013454), selenium (0\u20130.5), and zinc (28\u201364). Microalgae contained low TPC (6\u201313 mg gallic acid equivalents (GAE) g 121 DW), except T. chuii (20 mg GAE g 121 DW). IVPD was high (>90 %) for B. braunii (A), P. aerugineum, and lipid-extracted N. granulata (B); mid-range (80\u201389 %) for P. tricornutum, N. granulata (A), B. braunii (B), Neochloris oleoabundans, T. chuii, and whole N. granulata (B); and lower (<80 %) for Acutodesmus dimorphus. Microalgal species P. tricornutum, B. braunii, N. granulata, and T. chuii had high protein (40\u201352 %), IVPD (82\u201397 %), and digestible protein (35\u201350 %), comparable to plant proteins used in animal feeds and aquaculture.Peer reviewed: YesNRC publication: Ye

E\ufb00ects of dietary protein and lipid levels and DP DE-1 ratio on growth, feed utilization and hepatosomatic index of juvenile haddock, Melanogrammus aegle\ufb01nus L.

Juvenile haddock, Melanogrammus aeglefinus L. (initial weight, 13.5 \ub1 0.1 g) were fed practical diets containing digestible protein to digestible energy (DP DE\u207b\ub9) ratios of 25-30 g DP MJ DE\u207b\ub9 as-fed using three protein levels (450, 500 and 550 g kg\u207b\ub9) each at two lipid levels (110 and 160 g kg\u207b\ub9) for 63 days. The results showed mean weight gain and feed conversion ratio were highest for diets containing 28.5 and 30.2 g DP MJ DE\u207b\ub9. DP DE\u207b\ub9 ratio had no significant effect on protein efficiency ratio except at the lowest level (24.7 g DP MJ DE\u207b\ub9) indicating a protein sparing effect of higher lipid when dietary protein is below the requirement. Haddock appears to preferentially use protein as the prime source of DE. DP DE\u207b\ub9 ratio had little effect on apparent digestibility (AD) of protein while AD of lipid was significantly affected. Significant differences in AD of energy and organic matter were found to be inversely related to the carbohydrate level of the diet. DP DE\u207b\ub9 ratios of 28.5 g DP MJ DE\u207b\ub9 or lower resulted in significantly higher hepatosomatic indexes. The highest whole-body nitrogen gains and energy retention efficiencies were achieved at 28.5 and 30.2 g DP MJ DE\u207b\ub9, whereas only slight differences in nitrogen retention efficiencies were observed. The highest levels of energy retained in the form of protein were achieved at 28.5 and 30.2 g DP MJ DE\u207b\ub9. The diet that provided the best growth, feed utilization and digestibility with minimal HSI contained 546 g kg\u207b\ub9 protein (513 g kg\u207b\ub9 DP), 114 g kg\u207b\ub9 lipid, 164 g kg\u207b\ub9 carbohydrate, 17.0 MJ kg DE\u207b\ub9 and a DP DE\u207b\ub9 ratio of 30.2 g DP MJ DE\u207b\ub9.Peer reviewed: YesNRC publication: Ye