Observations on the distribution, ecology, and behaviour of bats on the Galapagos Islands

The distribution of bats on five Galapagos islands was assessed using ultrasonic detectors that can identify the feeding calls of different bat species. Red bats ( Lasiurus brachyotis ) were present on Santa Cruz and San Cristobal. Hoary bats ( L. cinereus ) were present on Santa Cruz, San Cristobal, Isabela, Floreana and Santiago. Species identifications were confirmed by recordings of bat calls, observations of flying bats, and the capture of 21 red bats and three hoary bats. There was no evidence of other species of bats on the Galapagos. Body size measurements were similar to those of South American red ( L. borealis ) and hoary ( L. c. villosissimus ) bats. Species status of L. brachyotis is not supported by morphological data. Both species were active in lowland and highland habitats, and foraging activity was high around street lights. Radio telemetry was used to locate day roosts and the nightly activity areas of four red bats in lowland areas of Santa Cruz. During the day, these bats roosted singly in the foliage of nine species of plant. Nightly activity areas were 10 to 20 ha in size. The activity areas of individuals overlapped, and included their known day roost sites. Both bat species were apparently more active in lowland habitats during the cool garua season, and less active in lowland habitats during the hot season. Female red bats were more abundant in lowland habitats during the cool season than were male red bats. Mesic, upland habitat may be critical to the survival of bats in the Galapagos.     

Influence of culinary treatment on the concentration and on the bioavailability of cadmium,chromium, copper,and lead in seafood

BackgroundSeafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed.MethodsBoiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed.ResultsThe analytes concentration in seafood without culinary treatment varied from 0.0030 μg g⁻¹ (shrimp) to 0.338 μg g⁻¹ (oyster) for Cd; 0.010 μg g⁻¹ (squid) to 0.036 μg g⁻¹ (oyster) for Cr; 0.088 μg g⁻¹ (scallop) to 8.63 μg g⁻¹ (oyster) for Cu, and < 0.005 μg g⁻¹ (shrimp, squid and oyster) to 0.020 μg g⁻¹ (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments.ConclusionCadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.     

Effect of cyclodextrins on the solubilization of lignoceric acid, ceramide, and cerebroside, and on the enzymatic reactions involving these compounds

alpha-Cyclodextrin at concentrations of 1-8 mM helps dissolve, in aqueous solution, fatty acids such as lignoceric, stearic, and palmitic, and complex lipids such as ceramide and cerebroside that contain these acids. Formation of an inclusion complex was indicated on examination of the solution by gel filtration. alpha-Cyclodextrin strikingly increased synthesis of ceramide from sphingosine and either free lignoceric or stearic acid by rat brain preparations. These results suggest the further use of alpha-cyclodextrin in lipid enzymology, especially in relation to sphingolipid metabolism.     

Update on the effects of vitamins A, C, and E and selenium on carcinogenesis

The effects of vitamins A, C, and E and of selenium on carcinogenesis are briefly summarized and updated. These vitamins and minerals were selected because they have been studied extensively in recent years with a variety of carcinogenesis models. The consumption of vitamin A and its precursors (carotenoids) has been negatively correlated with cancer at a number of sites, particularly the lung. Animal investigations on vitamin A involvement in carcinogenesis have generally been of three types: those assessing the effect of vitamin A deficiency, the effect of excess vitamin A, or the effect of supplementation with synthetic analogs of vitamin A. Vitamin A deficiency had no effect on salivary gland carcinogenesis, enhanced urinary bladder, lung, and liver carcinogenesis, and inhibited colon carcinogenesis. Excess of various forms of vitamin A enhanced or inhibited skin tumorigenesis, inhibited mammary carcinogenesis in rats (but not in mice), and carcinogenesis of the forestomach, liver, and urinary bladder (with one model, but not with another), or enhanced or did not influence lung carcinogenesis. Vitamin A analogs have enhanced or inhibited skin tumorigenesis, inhibited salivary gland, mammary, and urinary bladder carcinogenesis, enhanced tracheal and liver carcinogenesis, and either enhanced or inhibited pancreas carcinogenesis, depending upon the model employed. Although retinoids have been shown to inhibit carcinogenesis at many sites, numerous negative studies have been reported and some reports have indicated enhanced carcinogenesis. The most convincing evidence for the involvement of vitamin C in cancer prevention is the ability of ascorbic acid to prevent formation of nitrosamine and of other N-nitroso compounds. In addition vitamin C supplementation was shown to inhibit skin, nose, tracheal, lung, and kidney carcinogenesis, to either not influence or enhance skin, mammary gland, and colon carcinogenesis, and to enhance urinary bladder carcinogenesis, when given as sodium ascorbate, but not when given as ascorbic acid. Like vitamin C, vitamin E can inhibit nitrosation. Vitamin E was shown to inhibit skin, cheek pouch, and forestomach carcinogenesis, to enhance or inhibit colon carcinogenesis, and to have no effect on or to inhibit mammary gland carcinogenesis, depending upon the method of vitamin E administration or the level of dietary selenium or dietary fat. Selenium effects on carcinogenesis have been recently reviewed and the present discussion only updates this area by indicating that enhancement of carcinogenesis by dietary selenium supplements has been observed in the liver, pancreas, and skin.(ABSTRACT TRUNCATED AT 400 WORDS)     

Morphological,cytochemical, and biochemical observations on the blood of the tuatara,Sphenodon punctatus

Abstract

Morphological features of the circulating blood cells of an adult female tuatara are described and illustrated. Mitosis in circulating erythrocytes and the occurrence of an intraerythrocytic haemogregarine parasite are noted. The packed cell volume (haematocrit) was 35%. There were about 310 000 erythrocytes and 7200 leucocytes per mm³ of blood. The lymphocyte was the predominant leucocyte, followed by the eosinophil, monocyte, neutrophil, and basophil. The eosinophils and neutrophils reacted positively to acid phosphatase and peroxidase; the neutrophils were also esterase positive, and all three granulocytes were PAS positive. Haemoglobin, plasma protein, glucose, sodium, potassium, cholesterol, and triglyceride levels were determined. The primitive nature of the tuatara is reflected in the morphological. mensural, and biochemical data presented.     

The Influence of Shoots, Roots, and Hormones on the Distribution of Leucine, Phosphate, and Benzyladenine

The problem studied was the control of the relative distributionof metabolites to the shoots and roots. The movement of radioactivityapplied as leucine, phosphate, or benzyladenine (BA) was followedin small regenerated bean plants in which the distribution ofradioactive sucrose had been previously studied. Removal ofeither the shoots or the roots greatly reduced the transportof radioactivity in their direction. Auxin and BA partiallyreplaced the growing regions, but their effects were in no wayspecific to the parts of the plant in which they are naturallyformed. Radioactivity from BA, in contrast to the other substanceswhich were studied, moved preferentially towards the shootsand not the roots. The results indicate that the relations betweengrowing shoot and roots involve a direct hormonal interaction.The sinks which develop in response to the hormones may havesome specificity in terms of the substances they require orproduce and whose transport they influence.     

Influence of age on the production of rat spermatozoa, on their concentration in the cauda epididymidis, and on FSH, LH and testosterone plasma levels

Testis samples were taken from young (3 months), middle-aged (12 months) and aged (24 months) male rats, processed, stained and examined via a light microscope. There were no prominent abnormal germinal epithelium and interstitial tissue. However, the aging process promoted a significant decrease in the mean amount of spermatids 19 per cross tubular section, and in the amount of Sertoli cells per cross tubular section in 24-month-old rats. The concentration of spermatozoa in the cauda epididymidis showed a gradual decrease from 3 to 12 and 24 months. After hCG injection all groups of animals exhibited an increase in plasma testosterone level, although the response was smaller in 12- and 24-month animals compared to the young mature (3 months) ones.     

Vegetation,environmental characteristics and ideas on the maintenance of alvars on the Bruce Peninsula,Canada

Abstract. Despite international recognition that alvar habitats are important reservoirs of biodiversity, they remain little studied in North America. In this paper, the results are reported on an investigation of alvars in the central portion of their known distribution on this continent. 210 plots were distributed among seven sites and were quantitatively sampled for vascular plants, lichens, bryophytes and a suite of environmental variables. Detrended and Canonical Correspondence Analyses and other methods were used to investigate differences among alvars, within alvars and between alvars and adjacent forested habitats. The plant communities and environmental conditions were highly similar among sites in the study region, yet very different from surrounding habitats. There were abrupt changes in vegetation and environmental conditions from alvar to forest, without the presence of transition zones in the vegetation or environmental gradients as the forest was approached. The environmental factors associated with the change from alvar to forest and with variation within alvar habitat were examined. Some alvars in the study were found to contain stunted, slow-growing trees reaching ages of 524 yr. These same sites appear to have remained unburned for several centuries, while other sites likely burned 90 yr ago. The plant communities were very similar between the alvars that lacked a major, biomass-removing disturbance in centuries and alvars that had experienced catastrophic fire relatively recently. Maintenance of the plant communities and open nature of alvars appears site-specific rather than habitat specific.     

Studies on the effects of certain salts on germination,on growth of root,and on metabolism

Summary The effects of different concentrations of KCl, K₂SO₄, MgCl₂ and MgSO₄ on the growth in length of the first seminal root of wheat, and on the change in fresh and oven-dry weight of the seedling and its component parts have been studied. The effect of mannitol was also investigated for comparison and to study the osmotic action. The effect of salts on root growth was dependent on salt species; all effects were specific to ions and not due to osmotic activity of solution. The growth of wheat roots was suppressed by concentrations of salts much lower than those required to suppress germination. All solutions of KCl from 0.1 to 50 me/l checked the growth of the root; the retardation increased with increase of concentration. In K₂SO₄ there was a slight activation of root growth for one day in 0.1 and 0.5 me/l; then the growth was suppressed after that. In all other concentrations from 1 to 50 me/l the growth was retarded. In MgCl₂ or MgSO₄ there was some activation of root elongation in 0.05, 0.1 and 0.5 me/l; but higher concentrations retarded root growth.     

Biodiversity,dynamics, and impact of chakras on the Ecuadorian Amazon

Aims Deforestation and biodiversity loss are two alarming, closely related problems, and the main factors triggering changes in land use. Indigenous agricultural practices in the western Amazon Basin are known as chakras, and their structure and dynamics are seemingly optimal for forest management. However, the variability in tree species and the degree of forest recovery after abandonment is poorly documented in this agroforestry system (AFS). The goals of this study were: (i) to investigate whether the different AFSs (chakras) preserve similar levels of forest diversity, (ii) to determine the effect of transformation of mature forests (MF) to chakras, in particular, forest alpha and beta diversity levels, and (iii) to investigate whether native tree species recovery leads to the original forest structure following chakra abandonment.     

蓖麻碱的提取、纯化、改性及其杀虫活性研究

蓖麻饼中含有生物碱等毒性物质,主要杀虫活性物质为蓖麻毒蛋白和蓖麻碱,蓖麻碱是蓖麻中的主要毒素之一,具有一定的生物活性。本文研究了蓖麻碱的提取、纯化,以及将所得蓖麻碱再进一步进行改性,探讨改性方法。采用红外光谱方法对蓖麻碱改性前后变化进行对比;并对提取、纯化以及改性过程中的各个环节的物质进行杀虫实验,对实验结果进行观察。结果表明,蓖麻碱的主要杀虫活性基团为氰基。     

Experimental studies on the drought, waterlogging, and frost tolerance of

Ascarina lucida Hook.f. (Chloranthaceae) is a small tree species endemic to New Zealand. The distribution of A. lucida suggests an inability to survive severe frosts or droughts. Therefore, peaks in the abundance of A. lucida in pollen records have usually been interpreted as indicating periods of mild, moist climates. The environmental tolerance of A. lucida seedlings to climatic extremes was experimentally tested by exposing seedlings to frost, drought, and waterlogged soil conditions. This research confirms the sensitivity of A. lucida to climatic extremes. Ascarina lucida has a similar drought tolerance to Coprosma grandifolia, a species known to be drought intolerant; seedlings had considerable tolerance of waterlogged soils, but exhibited reduced root weights when severely waterlogged; and a frost of -2°C resulted in complete mortality for seedlings sourced from lowland and submontane populations. Peaks in the abundance of A. lucida can be attributed, at least in part, to periods of warm, wet climate. However, the early successional nature of this species also suggests that disturbance regime plays an important role in regulating its distribution and abundance.     

Shellfish, Gender, and Status on the Northwest Coast: Reconciling Archeological, Ethnographic, and Ethnohistorical Records of the Tlingit

Archeological, ethnographic, and ethnohistorical data provide ambiguous evidence of the dietary and economic importance of shellfish in Northwest Coast cultures. In the case of the Tlingit, I find that understanding shellfish from an emic perspective is critical to reconciling these equivocal data on economic importance. The Tlingit associated shellfish with poverty, laziness, and ritual impurity, and those who sought to be "ideal" persons avoided shellfish. An individual's rank and gender determined the degree to which such dietary guidelines were actually followed. The social and symbolic meaning of shellfish in Tlingit culture is partly explained by ecological factors, including the danger of paralytic shellfish poisoning. The analysis also reveals a number of biases inherent in the ethnographic and archeological data.     

Effect of the arginine analog,canavanine, on the synthesis and secretion of procollagen

Canavanine was shown to competitively inhibit the activation of arginine when tested with tRNA and synthetases prepared from whole chick embryos. The canavanine has no effect when tested with other amino acids. The K_m for arginine was 2.5 μm and the K_i for canavanine was 35 μm. When fibroblasts from embryonic chick tendons were incubated with [³H]arginine and increasing concentrations of canavanine, there was a progressive decrease in the incorporation of [³H]arginine so that at 3 mm the incorporation into nondialyzable protein was only 14% of the control. A much smaller decrease in the incorporation of other radioactive amino acids was observed. Amino acid analysis of proteins isolated from cells incubated with canavanine showed conclusively that the analog was incorporated. When the cells were incubated with [¹⁴C]proline or [³H]glycine and 3 mm canavanine, the labeled procollagen containing the canavanine was secreted more slowly than normal and accumulated intracellularly. The retained procollagen chains were normally hydroxylated, disulfide linked, and triple helical. However, slab gel electrophoresis in sodium dodecyl sulfate demonstrated that they migrated with a lower mobility than control procollagen chains. We postulate that incorporation of canavanine inhibits normal proteolytic processing of signal sequences resulting in delayed secretion of the procollagen.     

Effect of UVB radiation on the survival, feeding, and egg production of the brackish-water copepod, Sinocalanus tenellus, with notes on photoreactivation

We examined the effects of UVB radiation on hatching success of eggs, survival of various naupliar and copepodite stages, and feeding and egg production of adult females of the brackish-water copepod, Sinocalanus tenellus, by exposure to varying doses of UVB irradiance in the laboratory. Artificial UVB radiation resulted in an increased mortality of eggs, nauplii and copepodites with increasing UVB doses. UVB induced damage was stage-specific with eggs being most susceptible (LD₅₀= 4.1 kJ m^–2 ) and adult females being least susceptible (LD₅₀= 16.7 kJ m^–2). Effects on feeding and egg production of adult females were significantly evident at UVB doses higher than 11.0 kJ m^–2 and 7.0 kJ m^–2, respectively. We also examined the photorepair response of eggs and various developmental stages in simultaneous irradiation of UVB and enhanced PAR. With enhanced PAR there was a considerable recovery against UVB damage, being higher for younger animals than older ones. In nature, however, solar UVB radiation may rarely cause appreciable damage to S. tenellus population due to optically high attenuation properties of their habitat waters.     

Coagulase-Negative,Novobiocin-Resistant Staphylococci on the Skin of Animals and Man,on Meat and in Milk

The occurrence of coagulase-negative, novobiocin-resistant staphylococci, i.e. Staphylococcus cohnii, Staphylococcus saprophyticus, Staphylococcus sciuri and Staphylococcus xylosus, on the skin of animals and man has been studied. On cultures from cats, cows, dogs, guinea pigs, mice, rabbits and sheep studied, such organisms were predominant among the coagulase-negative staphylococci. From the skin of the hands of 21 of 38 persons whose professions brought them into contact with animals, e.g. inséminât ors, slaughterhouse workers and veterinarians, coagulase-negative, novobiocin-resistant staphylococci were isolated. This finding contrasted with that regarding 50 persons lacking such contacts, of whom only 1 harboured such bacteria. S. saprophyticus was isolated only from those slaughterers presenting with wounds on their hands. Coagulase-negative, novobiocin-resistant staphylococci were also isolated from every second specimen collected from the surface of meat at a slaughterhouse. No difference in the culture results could be demonstrated from specimens collected before and after cutting-up of the carcasses. Of 26 strains of coagulase-negative, DNase-negative staphylococci isolated from milk with pathological CMT, all but 5 were novobiocin-resistant. Fifteen were classified as S. xylosus, 4 as S. sciuri and 1 as S. cohnii. Of another 15 DNase-positive strains, 3 were resistant to novobiocin. Finally, clinical infections with coagulase-negative, novobiocin-resistant staphylococci in man, e.g. urinary tract infections caused by S. saprophyticus, are considered in relation to possible contagious reservoirs and modes of spread.     

Retrospective on the origin,intent, and impact of the Gutshops and some directions for the future

The eighth in a series of workshops on fish feeding ecology (“Gutshops”) was held in 2015, continuing a tradition started in 1976 that expanded in scope and participation. Topics in early Gutshops focused on methodology and analysis, and evolved to include niche overlap, competition, nutrition, and community trophic interactions. Major accomplishments were enhanced communications, standardization, design and evolution of indices (IRI, GII, PSIRI, etc.), statistical improvements, graphics, and chemical studies such as stable isotope and fatty acid analyses. Future directions, some of which were presented at the 2015 meeting, include internal tags (detecting feeding through movements, acidity, temperature, etc.), additional stable isotope and fatty acid analyses, genetic identification of prey and physiological indicators (enzyme analysis and digestion processes).     

Histochemical studies on the morphology of the golgi apparatus and on the distribution of hexokinase,L-gulonolactone oxidase,xylulose reductases,and ascorbic acid in the locus coeruleus of the rabbit

Summary Detailed histochemical studies have been conducted on the distribution of thiamine pyrophosphatase (TPPase), hexokinase and glucokinase (HK), L-gulonolactone oxidase (GO), D-xylulose reductase (DX), L-xylulose reductase (LX) and ascorbic acid (AC) in every component of the locus coeruleus (LC) of the healthy adult male rabbit.The LC consisted of medium-sized neurons and small neurons. Both types of neurons were classified into the same five categories on the basis of the morphology of the Golgi apparatus (GA). Many intermediate forms were observed between these different categories. The present results concerning TPPase may indicate that each type of neuron goes through cyclic activity.The GA of the small neurons showed little variation in its reactivity and volume in each category and no disintegration or budding-off. These neurons were mildly positive for the HK test, and negative for the GO, DX, LX and AC tests in contrast to the medium-sized neurons. These results may suggest that the small neurons are metabolically inactive, and that they have a different function from the medium-sized neurons.The morphology of the GA of the medium-sized neurons was basically similar to that described for motor neurons. It was considerably different from the morphology of the GA reported in the dorsal vagal nucleus (X) and hypothalamic neurosecretory nuclei (HMN) of the rabbit. These results suggest that the medium-sized neurons of the LC may be motor neurons, and that they may not have a neurosecretory function.The medium-sized neurons showed strong activity whereas the surrounding glial cells and neuropil exhibited mild activity in the HK test. These findings may suggest that these neurons get their energy source directly from the circulating blood.The medium-sized neurons were mildly to moderately positive for the DX and LX tests, and some of them were strongly positive for the GO test. Positive granules showed the tendency to accumulate in a proximal part of the main cell process and the part of perikaryon adjacent to it for the AC test. On the basis of these results, it is suggested that there is a strong possibility that at least some of the medium-sized neurons of the LC have the ability to synthesize vitamin C. This ability may be intimately related to the ontogenetical development of catecholamine.     

Effects of aging and dietary restriction on ubiquitination, sumoylation, and the proteasome in the spleen

In the present study, we demonstrate for the first time that aging increases the levels of ubiquitinated protein in the spleen, and that dietary restriction (DR) significantly reduces these age-related increases in ubiquitinated protein. Sumoylated protein, proteasome subunits, and a protein essential for proteasome biogenesis (POMP1) were also increased with age in the spleen but were not significantly affected by DR. Chymotrypsin-like proteasome activity was elevated in the aged spleen, and was not significantly altered by DR. Together, these data demonstrate for the first time the multiple effects of aging and DR on ubiquitination, sumoylation, and the proteasome in the spleen.