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1.
No consensus exists concerning the mechanisms, distribution,or adaptive significance of consciousness. Agreement on anyone of these issues would aid in resolving others. Given a reliablebehavioral or neuroanatomical test for consciousness, we couldmap its distribution and describe its evolution. Conversely,if we knew its distribution, we could assess its adaptive valueand look for similarly distributed neuroanatomies to help usget at its mechanisms. Morgan's Canonthe rule that we should avoid attributinghumanlike mental states to other animals whenever possibleimpedesthe use of the comparative method in unraveling this knot. Ifinterpreted in this context as a parsimony criterion, Morgan'sCanon is logically equivalent to epiphenomenalism. It is parsimoniousif and only if conscious mental events play no causal role inhuman behavior and human consciousness has no adaptive significance.Rejecting this conclusion entails rejecting the parsimony interpretationof Morgan's Canon. 相似文献
2.
I M Elayan D C Cartmill C B Eckersell J Wilkin W W Winder 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1991,198(1):569-571
Malonyl-CoA, the inhibitor of carnitine palmitoyl transferase I, has been examined in this study in the muscle and liver of diabetic rats. Male Sprague-Dawley rats were rendered diabetic with streptozotocin (6 mg/100 g body wt). The gastrocnemius/plantaris muscles and liver samples were frozen at liquid nitrogen temperature. Muscle malonyl-CoA was 1.8 +/- 0.2 pmol/mg in control rats and 1.5 +/- 0.2 pmol/mg in the diabetic rats. This difference was not statistically significant. Liver malonyl-CoA of control rats was 8.6 +/- 0.8 pmol/mg, in comparison to 4.3 +/- 0.6 pmol/mg in diabetic rats. In the liver, high concentrations of malonyl-CoA inhibit fatty acid oxidation and ketogenesis. Failure of malonyl-CoA to decline in muscle in the diabetic may be responsible in part for the diversion of fatty acids to the liver, thereby enhancing hepatic fatty acid oxidation and ketogenesis. 相似文献
3.
M Cartmill 《American journal of physical anthropology》1979,50(4):497-509
Friction of volar skin on wood is not proportional to load in human beings and prosimians, but to load raised to a fractional power. This meets theoretical expectations for the frictional characteristics of convex elastic surfaces. Although this enables small clawless primates to cling to steeper slopes and larger vertical supports than would otherwise be possible, the magnitude of the effect is not great enough to overcome the disadvantages of clawlessness in climbing vertical or steeply-sloping tree trunks and branches. In human subjects, friction appears to be more nearly proportional to load than in small prosimians used as experimental subjects. It is suggested that this is due to the fact that the small animals have discrete, elevated volar pads. Pad coalescence in large primates may be an adaptation for increasing the power to which load must be raised to become proportional to friction; increasing this exponent yields more friction per unit of adduction force on supports that are small relative to the animals' dimensions and weights. 相似文献
4.
Marijn Rutgers Daniël BF Saris Wouter JA Dhert Laura B Creemers 《Arthritis research & therapy》2010,12(3):R114
Introduction
Intraarticular administration of autologous conditioned serum (ACS) recently demonstrated some clinical effectiveness in treatment of osteoarthritis (OA). The current study aims to evaluate the in vitro effects of ACS on cartilage proteoglycan (PG) metabolism, its composition and the effects on synovial fluid (SF) cytokine levels following intraarticular ACS administration. 相似文献5.
The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region. 相似文献
6.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected. 相似文献
7.
Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m3 was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biological control. However, at the marginal value product of water, the inclusion of the costs of damage to infrastructure, or the adverse effects of water hyacinth on biodiversity, would justify the use of biological control, even at the low transpiration rate. 相似文献
8.
9.
R Gon?alves LA Szmuchrowski LS Prado BP Couto JCQ Machado VO Damasceno JA Lamounier 《Biology of sport / Institute of Sport》2015,32(3):255-260
The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. 相似文献
10.
Our objective was to determine the feasibility of prompt reinsemination of dairy cows when diagnosed not pregnant 27-29 days after first-service timed AI (TAI). We assumed that a first-wave dominant follicle was present at that time that would ovulate in response to GnRH once precocious luteal regression was induced after administration of PGF(2alpha). Cows that had not been detected in estrus and reinseminated by Days 27-29 after a first-service TAI were diagnosed not pregnant by ultrasonography. Nonpregnant cows from three herds were assigned randomly to receive either no further treatment until reinsemination (controls; n=189); 25mg i.m. of PGF(2alpha) and then reinsemination according to detected estrus (81 of 108) or at 72-80h after PGF(2alpha) treatment (PGF) in the absence of estrus (27 of 108); or 25mg i.m. of PGF(2alpha) followed by 100 microg i.m. of GnRH 48h later (PGF+GnRH) and then reinsemination after detection of estrus (9 of 160) or at 16-20h after GnRH (151 of 160). Blood samples were collected at the time of the not-pregnant diagnosis and again 48h later. Concentrations of progesterone before treatment with PGF(2alpha) were elevated (<1ng/ml) in 61% of the cows when PGF(2alpha) was administered and 81% of the cows given PGF(2alpha) had low (<1ng/ml) concentrations of progesterone 48h after PGF(2alpha). Treated cows were re-inseminated earlier (P<0.01; 31+/-1days) after first-service TAI than controls (55+/-1days). Conception rates after treatment were not different among treatments: PGF (22%), PGF+GnRH (23%), and control (23%). Average intervals from calving to conception were 22-23 days less (P<0.001) in treated cows than in controls. We concluded that treating nonpregnant cows with PGF(2alpha) on Days 27-29 after insemination produced acceptable conception rates when inseminations were made after detected estrus or when TAI was used after GnRH treatment. Further, both treatments reduced days between first-service TAI and second inseminations, and days from calving to conception. 相似文献