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91.

The present study describes a new regeneration system based on somatic embryogenesis from mature endosperm Passiflora cincinnata Mast. cultures. Moreover, the morpho-agronomic and phenological traits, as well as enzymatic activity of regenerated triploid emblings are compared to those of diploids. Mature endosperms were cultured on Murashige and Skoog medium supplemented with various concentrations (4.5–45.2 µM) of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.5 μM 6-benzylaminopurine (BA). No plant growth regulators were included in the control group. Embryogenic calli were observed only in treatments supplemented with 13.6 and 18.1 µM 2,4-D?+?4.5 µM BA, with the highest number of somatic embryos per explant and regenerated plants (emblings) obtained with 18.1 µM 2,4-D. Most emblings (70%) were triploid (2n?=?3x?=?27), with a DNA amount (4.38 pg) similar to that of endosperm and 1.5 times greater than in diploid P. cincinnata seedlings (2n?=?2x?=?18), that contained 2.98 pg of DNA. While the number of organs and/or structures was akin to that in diploids, triploid emblings generally exhibited larger and longer vegetative and floral structures. The flower lifespan was also slightly altered by triploidy, nectar concentration was 27% higher, and the activity of plant defense enzymes β-1,3-glucanase and polyphenol oxidase was 29.8% and 22.1% higher. This study describes a new regeneration system for the production of phenotypic variants of this ornamental passion fruit species, opening new perspectives for future studies on genetic passion fruit breeding.

  相似文献   
92.
In species in which adults of the two sexes show long-term association, males often engage in acts of assistance (“services”) aimed at females and/or their young in various behavioural contexts that are not reciprocated. We conducted a quantitative review of the primate literature on sex differences in involvement in protection against predation. We found that males were more likely to be at the front of group progressions, especially in contexts of increased risk, were more vigilant, sometimes to the point of becoming sentinels, were more active in mobbing, and were far more likely to counter-attack felids and monkey-eating raptors than females did. Our evaluation showed that these services may be an expression of male parental care or aimed at bonded partners, but we also encountered many cases in which non-sires, unrelated to either females or immatures, provide them. We hence investigate explanations invoking group augmentation or costly signalling. Currently, available data on male anti-predation services in nonhuman primates do not allow us to distinguish among them, although costly signalling better explains data on birds and humans. We develop predictions that will allow more detailed tests of the various hypotheses for this understudied phenomenon.  相似文献   
93.
Mycopathologia - Paracoccidioidomycosis (PCM) is a systemic mycosis caused by a group of cryptic species embedded in the Paracoccidioides brasiliensis complex and Paracoccidioides lutzii. Four...  相似文献   
94.
Molecular and Cellular Biochemistry - The nicotinamide adenine dinucleotide (NAD+) is an essential redox cofactor, involved in various physiological and molecular processes, including energy...  相似文献   
95.
Organisms Diversity & Evolution - The South African coast is known to harbor four different species of intertidal oribatid mites and their distribution strongly correlates with marine...  相似文献   
96.
Model-based online optimization has not been widely applied to bioprocesses due to the challenges of modeling complex biological behaviors, low-quality industrial measurements, and lack of visualization techniques for ongoing processes. This study proposes an innovative hybrid modeling framework which takes advantages of both physics-based and data-driven modeling for bioprocess online monitoring, prediction, and optimization. The framework initially generates high-quality data by correcting raw process measurements via a physics-based noise filter (a generally available simple kinetic model with high fitting but low predictive performance); then constructs a predictive data-driven model to identify optimal control actions and predict discrete future bioprocess behaviors. Continuous future process trajectories are subsequently visualized by re-fitting the simple kinetic model (soft sensor) using the data-driven model predicted discrete future data points, enabling the accurate monitoring of ongoing processes at any operating time. This framework was tested to maximize fed-batch microalgal lutein production by combining with different online optimization schemes and compared against the conventional open-loop optimization technique. The optimal results using the proposed framework were found to be comparable to the theoretically best production, demonstrating its high predictive and flexible capabilities as well as its potential for industrial application.  相似文献   
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98.
Variability in floral, fruit, and seed characteristics, and oil content of 15 accession of Jatropha curcas during early development were assessed during two flowering periods in south Florida subtropical climate. The two flowering periods had leaf flushing in March. Field evaluation using 18 quantitative traits showed significant variation among accessions. The number of female flowers and female : male flower ratio ranged from 1 to 15 and 1 : 8.8 to 1 : 67.8, respectively. Fruit set by natural pollination was 89 and 66% during the first (1st) and second (2nd) flowering periods, respectively. A higher number of female‐type inflorescences were observed during summer. There were significant differences in seed traits, except for number of seeds per fruit. Accession TREC 31 had the highest individual seed dry weight and 100‐seed weight (0.83 g and 79.7 g, respectively). The oil content varied from 19.30% to 35.62%. Seed dry weight had positive correlation with seed fresh weight, seed length, seed thickness, seed width, and 100‐seed weight, but negative correlation with oil content. Based on the cluster analysis using 15 morphological traits, jatropha accessions were grouped into five main clusters and accessions from different geographic regions grouped together in a cluster. Principal component analyses (PCA) revealed morphological variation. The first three components explained 73.5% of the total variation and seed dry weight, 100‐seed weight, total flowers per inflorescence, male flowers per inflorescence and fruit set can be used to distinguish accessions. The PCA also indicated that flowering traits were more influenced by seed origin while seed traits were affected by flowering spans. Although evaluations were performed in plants during the juvenile phase, accessions TREC 31 and TREC 55 had superior averages for almost all characters evaluated. These results provide a preliminary assessment of the high variability in jatropha accessions evaluated and their potential for use in breeding and genetic improvement programs.  相似文献   
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100.

Background

Anemia is common and is associated with impaired clinical outcomes in diabetic chronic kidney disease (CKD). It may be explained by reduced erythropoietin (EPO) synthesis, but recent data suggest that EPO-resistance and diminished iron availability due to inflammation contribute significantly. In this cohort study, we evaluated the impact of hepcidin-25—the key hormone of iron-metabolism—on clinical outcomes in diabetic patients with CKD along with endogenous EPO levels.

Methods

249 diabetic patients with CKD of any stage, excluding end-stage renal disease (ESRD), were enrolled (2003–2005), if they were not on EPO-stimulating agent and iron therapy. Hepcidin-25 levels were measured by radioimmunoassay. The association of hepcidin-25 at baseline with clinical variables was investigated using linear regression models. All-cause mortality and a composite endpoint of CKD progression (ESRD or doubling of serum creatinine) were analyzed by Cox proportional hazards models.

Results

Patients (age 67 yrs, 53% male, GFR 51 ml/min, hemoglobin 131 g/L, EPO 13.5 U/L, hepcidin-25 62.0 ng/ml) were followed for a median time of 4.2 yrs. Forty-nine patients died (19.7%) and forty (16.1%) patients reached the composite endpoint. Elevated hepcidin levels were independently associated with higher ferritin-levels, lower EPO-levels and impaired kidney function (all p<0.05). Hepcidin was related to mortality, along with its interaction with EPO, older age, greater proteinuria and elevated CRP (all p<0.05). Hepcidin was also predictive for progression of CKD, aside from baseline GFR, proteinuria, low albumin- and hemoglobin-levels and a history of CVD (all p<0.05).

Conclusions

We found hepcidin-25 to be associated with EPO and impaired kidney function in diabetic CKD. Elevated hepcidin-25 and EPO-levels were independent predictors of mortality, while hepcidin-25 was also predictive for progression of CKD. Both hepcidin-25 and EPO may represent important prognostic factors of clinical outcome and have the potential to further define “high risk” populations in CKD.  相似文献   
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