Composition of organic C fractions in soils of different texture affected by sugarcane monoculture     

Anna Kusumawati  Benito Heru Purwanto  Makruf Nurudin 《Soil Science and Plant Nutrition》2020,66(1):206-213

ABSTRACT

Sugarcane is a strategic commodity in Indonesia. It is usually raised in a monoculture system. There is a lack of information about the effects of extended sugarcane monoculture on the soil carbon fraction. The aim of this study was to determine the relative changes in the soil organic C fractions in response to the duration of sugarcane monoculture on Entisols, Inceptisols, and Vertisols. The measured variables were the percentages of sand, silt, and clay, organic matter (OM), total nitrogen (TN), pH (H₂O), cation exchange capacity (CEC), NH₄ ⁺, NO₃ ^-, labile carbon fraction (soil carbon mineralization (C-Min), soil microbial carbon (C-Mic), and carbon particulate organic matter (C-POM)), and stable carbon fraction (humic and fulvic acids). Soil type with sugarcane monoculture period had significant influences on the percentages of clay, sand, silt, CEC, and pH (H₂O). Soil type and sugarcane monoculture period had no apparent significant effect on C-Min or C-POM but did significantly influence C-Mic. The humic and fulvic acid levels in all three soil types were affected by the duration of sugarcane monoculture. To establish the impact of long-term sugarcane monoculture on the physicochemical properties of soils with various textures, it is more appropriate to measure the soil stable carbon fractions such as humic and fulvic acid rather than the soil labile carbon fractions such as C-Min, C-POM, or C-Mic.  相似文献   

Improved milk production performance of smallholder farms in West Java (Indonesia)     

Pria Sembada  Guillaume Duteurtre  Bagus Priyo Purwanto  Suryahadi 《Tropical animal health and production》2016,48(4):793-799

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Effects of gossypol from cottonseed cake on the blood profile in sheep     

Antônio Carlos Lopes Câmara  André Menezes do Vale  Cláudio Roberto Scabelo Mattoso  Marília Martins Melo  Benito Soto-Blanco 《Tropical animal health and production》2016,48(5):1037-1042

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Glutathione content of in vivo and in vitro matured canine oocytes collected from different reproductive stages   总被引：3，自引：0，他引：3  

Kim MK  Hossein MS  Oh HJ  Fibrianto HY  Jang G  Kim HJ  Hong SG  Park JE  Kang SK  Lee BC 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(6):627-632

Glutathione (GSH) concentrations of oocytes are considered as an important marker of the cytoplasmic maturation. The present study was designed to compare GSH concentrations of in vivo and in vitro matured canine oocytes. In vivo matured oocytes were collected 72 hr after ovulation by flushing fallopian tubes after laparotomy. Ovaries were collected from bitches with different reproductive stages, and collected oocytes were divided into 2 groups according to the size viz. < 120 microm and > 120 microm in diameter and cultured for 72 hr in Tissue Culture Medium-199 supplemented with 10% FBS, 2.2 mg/ml sodium bicarbonate, 2.0 microg/ml estrogen, 0.5 microg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin-streptomycin solution in the presence or absence of 50 microM beta-mercaptoethanol. GSH concentrations were determined by the dithionitrobenzoic acid-glutathione disulfide (DTNB-GSSG) reductase recycling assay. GSH concentrations of immature canine oocytes were 2.9 and 3.8, 3.5 and 6.8, and 3.1 and 6.5 pM/oocyte for < 120 microm and > 120 microm in diameter oocyte groups at anestrous, follicular and luteal stage, respectively (P<0.05). In vivo matured oocytes had significantly higher GSH concentrations compared with in vitro matured oocytes. The GSH content was 19.2 pM/oocyte for in vivo matured oocytes, while 4.1 to 8.1 and 5.7 to 13.2 pM/oocyte for in vitro matured oocytes cultured in the absence or presence of beta-mercaptoethanol, respectively (P<0.05). Presence of beta-mercaptoethanol increased GSH synthesis in canine oocytes cultured in vitro, and oocytes collected from follicular and luteal stage was superior to anestrus oocytes.  相似文献   

Occurrence of the temperature-sensitive hemagglutinin among avian Escherichia coli     

Delicato ER  de Brito BG  Konopatzki AP  Gaziri LC  Vidotto MC 《Avian diseases》2002,46(3):713-716

In this study, we determined the occurrence of the tsh gene among 305 Escherichia coli isolates from chickens by means of the polymerase chain reaction and agglutination of chicken erythrocytes; 200 of those isolates were obtained from chickens with colisepticemia, 52 isolates were from lesions of cellulitis, and 53 were from feces of normal chickens. The tsh gene was found in 79 (39.5%) isolates from colisepticemia, in 10 (19%) cellulitis-derived E. coli isolates, and in two (3.8%) fecal isolates. Among the tsh+ strains, 68 (86%) isolates from colisepticemia and nine (90%) from cellulitis agglutinated chicken erythrocytes in the presence of mannose, after growing the strains on colonization factor antigen agar plates at 26 C, which confirms a correlation between mannose-resistant hemagglutination and expression of hemagglutinin Tsh. These results show, for the first time, the presence of the gene tsh in cellulitis-derived E. coli isolates; the high frequency of this gene among avian pathogenic E. coli isolates in Brazil indicates that its putative role as a virulence factor should be studied more thoroughly.  相似文献   

Virulence factors of avian pathogenic Escherichia coli isolated from broilers from the south of Brazil     

da Rocha AC  da Silva AB  de Brito AB  Moraes HL  Pontes AP  Cé MC  do Nascimento VP  Salle CT 《Avian diseases》2002,46(3):749-753

Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis.  相似文献   

Comparative study of the mechanical properties of polyester resin with and without reinforcement with fiber-glass and furcraea cabuya fibers     

Alejandro Brenes-Acosta  Benito A. Stradi-Granados 《Fibers and Polymers》2014,15(10):2186-2192

A commercially available polyester resin was reinforced with cabuya fibers. The experimental variables were the fiber loading and the length of the fiber. Tensile strength, flexural strength, and the Izod impact resistance were measured for the samples and compared to the polyester resin performance without reinforcement. Mechanical properties of the cabuya fiber reinforced material were also compared with the same resin but reinforced with glass fibers. An increase in fiber load decreases the tensile strength for the cabuya reinforced composite, where a value of 52.6 MPa corresponded to the tensile stress of the resin without reinforcement and a value of 34.5 MPa for the best reinforcement achieved with cabuya. An increase in both fiber load and length increases the Young’s modulus of the cabuya reinforced material, and a maximum value of 2885 MPa was obtained. The Young’s modulus and impact resistance values for the cabuya composite (2885 MPa and 100.87 J/m, respectively) reached higher values than those obtained for non-reinforced polyester material (2639 MPa and 5.82 J/m, respectively), and lower than the glass fiber composite (5526 MPa and 207.46 J/m, respectively); while the tensile and flexural strength obtained for the cabuya composite (34.5 MPa and 32.6 MPa, respectively) were lower than the unreinforced (52.6 MPa and 62.9 MPa, respectively) and glass fiber reinforced polyester (87.3 MPa and 155 MPa, respectively).  相似文献   

Island differences in population size structure and catch per unit effort and their conservation implications for Komodo dragons     

Tim S. Jessop  Thomas Madsen  M. Jeri Imansyah  Heru Rudiharto  John A. Phillips 《Biological conservation》2007,135(2):247-255

Species inhabiting archipelagos are often characterised by high levels of interpopulation divergence (e.g. size related traits). This divergence may, in turn, influence their life-history. To facilitate better management and conservation of the Komodo dragon (Varanus komodoensis), an island endemic, we identified demographic differences between two island populations in Komodo National Park, Indonesia. Comparison of data collected from dragon populations inhabiting Rinca Island and the much smaller Gili Motang Island indicated that between 1994 and 2004, the Komodo dragon population on Gili Motang significantly decreased its: (1) mean body mass, (2) body condition and (3) relative abundance. These results suggest that the numerically small Gili Motang population was oscillating downwards; in contrast, the Rinca Island population had been relatively stable. More importantly these results emphasize the necessity for managers of this priority conservation species to understand further the inherent functional differences among dragon populations to develop island specific management units. Current management practices (e.g. monitoring) instigated by Komodo National Park management ignore small island dragon populations and thus run the risk of being unable to detect adverse effects for populations that are potentially most prone to decline.  相似文献   

Heavy metal, total arsenic, and inorganic arsenic contents of algae food products     

Almela C  Algora S  Benito V  Clemente MJ  Devesa V  Súñer MA  Vélez D  Montoro R 《Journal of agricultural and food chemistry》2002,50(4):918-923

The total arsenic, inorganic arsenic, lead, cadmium, and mercury contents of 18 algae food products currently on sale in Spain were determined. The suitability of the analytical methodologies for this type of matrix was confirmed by evaluating their analytical characteristics. The concentration ranges found for each contaminant, expressed in milligrams per kilogram of dry weight, were as follows: total arsenic, 2.3-141; inorganic arsenic, 0.15-88; lead, < 0.05-1.33; cadmium, 0.03-1.9; and mercury, 0.004-0.04. There is currently no legislation in Spain regarding contaminants in algae food products, but some of the samples analyzed revealed Cd and inorganic As levels higher than those permitted by legislation in other countries. Given the high concentrations of inorganic As found in Hizikia fusiforme, a daily consumption of 1.7 g of the product would reach the Provisional Tolerable Weekly Intake recommended by the WHO for an average body weight of 68 kg. A more comprehensive study of the contents and toxicological implications of the inorganic As present in the algae food products currently sold in Spain may be necessary, which might then be the basis for the introduction of specific sales restrictions.  相似文献   

Simultaneous and sensitive detection of three foodborne pathogens by multiplex PCR, capillary gel electrophoresis, and laser-induced fluorescence     

Alarcón B  García-Cañas V  Cifuentes A  González R  Aznar R 《Journal of agricultural and food chemistry》2004,52(23):7180-7186

The simultaneous detection of Staphylococcus aureus, Listeria monocytogenes, and Salmonella spp. has been approached by a new multiplex PCR-based procedure followed by capillary gel electrophoresis with laser-induced fluorescence detection (multiplex-PCR-CGE-LIF). As compared to slab gel electrophoresis, the use of CGE-LIF improved from 10- to 1000-fold the sensitivity of the multiplex PCR analysis, allowing the detection of 2.6 x 10(3) cfu mL(-1) of S. aureus, 570 cfu mL(-1) of L. monocytogenes, and 790 cfu mL(-1) of Salmonella in artificially inoculated food, without enrichment. Following 6 h of enrichment, as low as 260, 79, and 57 cfu mL(-1) of S. aureus, L. monocytogenes, and Salmonella, respectively, were detected. The CGE-LIF method is shown to be reproducible, providing relative standard deviation (RSD) values lower than 0.8% for analysis time and lower than 5.8% for peak areas. The multiplex-PCR-CGE-LIF proved a powerful analytical tool to detect various food pathogens simultaneously in a fast, reproducible, and sensitive way.  相似文献