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41.
The poorly regulated aquarium trade in live corals poses yet another threat to fragile coral reef ecosystems. The Indonesian authorities routinely allocate some of the highest trade quotas in South Sulawesi to Heliofungia actiniformis despite a lack of data on the impacts of current collection practices on this species. Semi-structured interviews with fishermen and in situ surveys revealed a size-selective fishery towards small polyps. This resulted in a shift of size-frequency distributions, and reduced overall abundances at harvested sites. Total mortality rates calculated using a catch curve approach at harvested sites were significantly higher compared to those known from unharvested sites for polyps sized 0-11 cm. Recorded exploitation rates were 0.1 and 0.7 for polyps sized 0-4 cm and 4-11 cm respectively. The application of a utility per recruit approach, calculated with a Thompson and Bell model, revealed maximum potential economic yield to occur at a size of 5 cm, corresponding to an age of 5 years. This is 5 years before the attainment of reproductive maturity, and 15 years before the attainment of maximum biomass yield per recruit. A predictive model indicated the need for a 5 cm size limit to curb economic overfishing, and protect attached anthocauli stalks capable of maintaining the trade through continued asexual reproduction. In addition, a reduction of exploitation rates for polyps in the 4-11 cm size bracket to 0.5 is urgently needed. Calculations reveal that this would in fact be possible without lowering current profits. Achieving long term sustainability will in addition to a reduction of harvest quotas necessitate an effective protection of spawning stocks through stricter enforcement of existing marine protected areas.  相似文献   
42.
Four parents [P. acutifolius var.acutifolius (A19), P. a.var. latifolius `Serowi' (A9),P. a. var. latifolius(A10), and P. vulgaris `Red Cloud' kidney (V1)] were used to create six interspecific recurrent and congruity backcross pedigrees (V1 × A9, A9 × V1, V1 × A10, A10 × V1, V1 × A19, A19 × V1) for evaluation of Rhizobium, Bradyrhizobium nodulation affinities and root peroxidase banding patterns. Most primary hybrids nodulated with all Rhizobium, Bradyrhizobium strains, while recurrent generations nodulated with strains of the recurrent parent, suggesting a number of independent loci and random assortment for strain-specific nodulation. A proximity matrix of nodulation phenotypes produced a cluster with V1, two recurrent and two congruity backcross hybrids with V1 as the cytoplasmic parent; a separate cluster with all primary interspecific and balanced, congruity backcross hybrids. A9 and A10were clustered the farthest away from V1. Root peroxidase zymograms of primary hybrids were the summation of the parents and controlled by independent loci. Advanced hybrids exhibited new root peroxidases, matching those found for otherPhaseolus spp., including ancestralP. coccineus. A proximity matrix of root peroxidase phenotypes produced a cluster with only A9 3V1F1, a cluster containing only A19 3V1 F2, and a large cluster with all P. acutifoliusparents and hybrids with P. acutifolius as the cytoplasmic parent in balanced hybrids or the majority parent in unbalanced hybrids. Estimation of genetic distances showed primary, interspecific hybrids to be more closely related with the cytoplasmic parent. Recurrent and congruity backcross generations varied in genetic distances between each respective parent. This is the first report of congruity backcrossing creating hybrids with biochemical traits of nonparental species. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
43.
This study aimed to investigate the differences in oxidative stress index (OSI) and kisspeptin levels in clinically asymptomatic dogs with cystic endometrial hyperplasia (CEH) compared to healthy and pregnant dogs, and to determine the usability of the obtained results in the diagnosis of asymptomatic CEH. The study comprised three groups; a healthy (n = 8), a pregnant (n = 10) and a CEH (n = 10). All dogs in the three groups were included in the study at the 30 ± 3th day after estrus, and blood samples were collected for analysis of kisspeptin, total antioxidant status (TAS), total oxidant status (TOS), progesterone (P4), estradiol (E2) and some biochemical parameters (TSH; thyroid stimulating hormone, ALT; alanine aminotransferase, AST; aspartate aminotransferase, ALP; alkaline phosphatase, LDH; lactate dehydrogenase, CRE; creatine and BUN; blood urea nitrogen). In addition, OSI value was calculated. P4 and ALT and BUN levels were significantly lower and higher in CEH group than the pregnant group, respectively (p < .05). While kisspeptin and TAS levels were significantly lower in CEH group compared to the healthy and pregnant groups (p < .01), OSI level increased dramatically. In conclusion, it was confirmed that CEH clearly affected kisspeptin and OSI levels, and it is thought that these parameters may be an alternative diagnostic tool for the detection of CEH after further studies.  相似文献   
44.
Changes in land use can significantly affect soil properties. This study was conducted in the Taleghan watershed of Tehran Province, Iran, to determine the effects of land use changes on soil organic matter (SOM) and soil physical properties including soil aggregate stability, saturated hydraulic conductivity, infiltration rate, available water content, total porosity and bulk density (BD). In the present study, two sites contained adjacent land uses of natural pasture and dryland farming were selected. Soil samples were taken from depths of 0–15 and 15–30 cm for each land use. The results indicated that the conversion of natural pasture to dryland farming led to a significant decrease in SOM at 0–30 cm in the first and second sites (24.7 and 44.2%, respectively). In addition, a significant increase in BD was observed at a depth of 0–30 cm in dryland farm soils (1.39 g cm–3) compared to pastureland (1.20 g cm–3) at the first site. An increase in BD was also observed at the same depth of dryland farm soils (1.46 g cm–3) and pastureland soils (1.42 g cm–3) at the second site. In addition, total porosity, mean‐weight diameter of aggregates, saturated hydraulic conductivity, available water content and estimated final infiltration rate showed significant differences between land uses. The results showed that the conversion of natural pasture to dryland farming alters soil properties that negatively affect soil productivity and erodibility. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
45.
PCR assay has been shown to be a promising option for the diagnosis of brucellosis. However, few studies have been performed with field samples in order to evaluate the assay as a diagnostic tool. In this study, routine use of a species-specific PCR assay previously developed for the identification of Brucella cultures was assessed for the detection of Brucella DNA directly from the stomach contents of aborted sheep fetuses. The assay is based on the insertion sequence IS711 in the Brucella chromosome. In the study, during 3 successive lambing seasons (1998-1999, 1999-2000 and 2000-2001) 126 aborted fetus samples each from different flocks and locations were examined. Brucella strains were isolated from 39 (31%) of the samples and all of the strains were identified as Brucella melitensis by biochemical characteristics, agglutination with monospecific A and M sera and PCR. Thirty-seven of 39 B. melitensis isolates were biotyped as biotype 3, and 2 isolates as biotype 1. From 38 of 39 culture positive fetal stomach contents B. melitensis-specific DNA was detected by PCR. PCR was found negative in all of the culture negative samples. Compared with culture, sensitivity and specificity of PCR were determined as 97.4 and 100%, respectively. The results indicate that this PCR procedure has a potential for use in routine diagnosis of sheep brucellosis.  相似文献   
46.
ABSTRACT Marginal chlorosis has affected strawberry production in France for about 15 years. A phloem-restricted uncultured bacterium, "Candidatus Phlomobacter fragariae," is associated with the disease. A large-scale survey for marginal chlorosis in French strawberry production fields and nurseries by polymerase chain reaction amplification of "Ca. P. fragariae" 16S rDNA revealed that symptoms of marginal chlorosis were not always induced by "Ca. P. fragariae" and that the stolbur phytoplasma could induce identical symptoms. "Ca. P. fragariae" was found to be predominant in strawberry production fields, whereas the stolbur phytoplasma was predominantly detected in nurseries. Two transmission periods of the disease, one in spring and the other from late summer to early fall, were evident. Cixius wagneri planthoppers captured on infected strawberry plants were demonstrated to be efficient vectors of "Ca. P. fragariae." The involvement in natural disease spread of the whitefly Trialeurodes vaporariorum, previously shown to acquire and multiply "Ca. P. fragariae" under greenhouse conditions, remains uncertain.  相似文献   
47.
The spinal nerve root origins of the cutaneous nerves innervating the canine pelvic limb were determined in 12 barbiturate-anesthetized, healthy dogs by stimulating the dorsal roots L1-S3 and recording the evoked-action potentials from each cutaneous nerve. The dogs were then euthanatized, identification of each dorsal root and cutaneous nerve was verified by dissection, and the type of lumbosacral plexus (prefixed, median fixed, or postfixed) was determined. With one exception, the dorsal cutaneous branches and lateral cutaneous branches of L1-L3 originated only from their corresponding spinal nerve roots. The genitofemoral nerve received afferent fibers predominantly from L3-L4 nerve roots. The lateral cutaneous femoral nerve originated from L3-L5 nerve roots, and the saphenous nerve from L4-L6 nerve roots. The proximal caudal cutaneous sural nerve originated from L6-S1. The lateral cutaneous sural nerve originated from L5-S1; the deep and superficial fibular nerves arose primarily from L6-L7. The distal caudal cutaneous sural nerve originated predominantly from L7-S1, and the medial cutaneous tarsal nerve originated from L6-S1. The medial plantar nerve originated predominantly from L6-S1 roots, whereas the lateral plantar nerve originated from L6-S2 roots. The middle clunial nerve received afferent fibers primarily from S1-S2; the caudal clunial nerve received fibers from S1-S3. The caudal cutaneous femoral nerve originated predominantly from L7-S2. The dorsal nerve of the penis originated predominantly from S1-S2, and the superficial perineal nerve originated from S1-S3. One dog had a prefixed plexus, 8 dogs had median-fixed plexuses, and 1 dog had a postfixed plexus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
48.
The aim of this research is to study the feasibility of removing nitrates from water by means of anion exchange. In the purposed work an attempt was made to utilize strong basic anion resin to remove nitrate in the presence of competitive anion. Amberjet Cl- 4200 ion exchange resin was used in a batch scale. The fixation rate of nitrate without the presences of any competitive anion was almost constant (94.60-96.43) when the nitrate concentrations are in the range of 100-150 mg L(-1). The fixation rate of nitrate in the presences of two competitive anions (sulphate and chloride) was reduced to 82% when the concentration of nitrate was 100 mg L(-1).  相似文献   
49.
Mycorrhiza can improve plant growth and increase nutrient uptake. This study was conducted as factorial experiment based on complete random design (CRD) to study effects of mycorrhiza inoculation under limited iron (Fe) condition on antioxidant activity, phenol content and photosynthesis trait of cucumber (Cucumis sativus cv. N3). Treatments were Johnson modified nutrient solution (MNS) with 25% Fe (MNS1) = 0.57 mg/L Fe, 50% (MNS2) = 1.14 mg/L Fe and 100% (MNS3) = 2.3 mg/L Fe and mycorrhiza inoculation (M+) and non-mycorrhiza inoculation (M?) with 3 replications under hydroponic conditions. The results showed that plant growth and shoot phenol content decreased in the MNS1 treatment; whereas phenol content of the root exudates and antioxidant activity significantly increased in this treatment. All photosynthesis attribute increased in the MNS3 treatment. Mycorrhiza inoculation increased plant growth, phenol content, antioxidant activity and photosynthesis trait of cucumber. Also, mycorrhiza inoculation enhanced SPAD value in the MNS2 treatment and photosynthesis rate, transpiration and mesophyll conductance in all the modified nutrient solutions. Moreover, mycorrhiza symbiosis was stimulated by the internal carbon dioxide (CO2) content of the stomata in the MNS2 and MNS3 treatments. Furthermore, Mycorrhiza inoculation improved phenol content of the shoots and roots in all the nutrient solutions, whereas antioxidant activity was affected by mycorrhiza inoculation only in the MNS2 treatment.  相似文献   
50.
  1. that the north Adriatic, the Tunisian continental shelf, the waters around Malta and the Italian Ionian Sea represent important areas for the conservation of rookeries in Greece, Libya and Turkey, respectively;
  2. that waters off the Italian peninsula and the islands of Lampedusa and Malta are mainly inhabited by individuals of Mediterranean origin, with a major contribution from the nearest and largest colonies, while Atlantic turtles are restricted to the western areas;
  3. that specific migratory routes exist from rookeries to foraging grounds;
  4. a poor bi‐parental genetic structuring, which suggests a high male‐mediated gene flow in the Mediterranean;
  5. mixing of small turtles in waters distant from natal rookeries, and recovery of structuring for large‐sized individuals; and
  6. that uncommon mtDNA haplotypes are more powerful markers than microsatellite alleles in assessing an individual's origin, owing to their higher geographic specificity.
Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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