Infestation and natural parasitism of aphids in single and mixed pastures of black oats and ryegrass

Some species of aphids are major pests on cereal crops and grass pastures. Usually these pests are not adequately controlled in pasture lands that become sources of aphid infestations to cereal crops. The dynamics of aphids and the incidence of natural enemies are less known in pasture systems than in cereal fields. The objective of this work was to assess the aphid infestation and natural aphid parasitism in different pasture composition. Three hypotheses were tested: 1- the aphid species composition in pastures may vary according to the cereal species in the field; 2- the mixture of two plant species can modify the amount and diversity of aphids; 3- the plant species composition of pasture fields influences the parasitism of aphids. Empirical data were obtained from three Poaceae fields: black oats (Avena strigosa L.), ryegrass (Lolium multiflorum L.), and a mixed field of black oats and ryegrass. The most abundant aphid species was Rhopalosiphum padi followed by Sitobion avenae. Plant species composition increases the amount and the parasitism rates of aphids. The mixture of heavily infested black oats with a poorly infested ryegrass resulted in reduction of aphid infestation in comparison with heavily-infested single plant species field. This is possible because the conditions are favorable for the development of parasitoid populations. Aphidius colemani was the main parasitoid found in these areas.

Single mothers and incentives to work: The French experience

This paper analyzes the effect of the 1998 reform of the French single parents allowanceon the labor supply of single mothers with very young children. The reform aimed atencouraging participation by allowing eligible single parents to accumulate benefits andlabor earnings for a limited period of time. Using data from the French EmploymentSurvey, the analysis shows that single mothers affected by the reform had experienced asignificant increase in their employment rate four years after the reform wasimplemented. During the same period, the employment rate of married mothers withyoung children did not experience a significant change, suggesting that at least part ofthe increase was a consequence of the reform. These results provide some evidence thatbenefit schedules that provide financial incentives to work can have significant effectsin getting single moms back to work, even in the presence of very young children.

State of Iowa’s Single Audit Report for the year ended June 30, 2008

State of Iowa’s Single Audit Report for the year ended June 30, 2008

Substance P-like-immunoreactive sensory neurons in dorsal root ganglia of the chick embryo: ontogenesis and influence of peripheral targets.

The expression of substance P (SP) was studied in sensory neurons of developing chick lumbosacral dorsal root ganglia (DRG) by using a mixture of periodic acid, lysine and paraformaldehyde as fixative and a monoclonal antibody for SP-like immunostaining. The first SP-like-immunoreactive DRG cells appeared first at E5, then rapidly increased in number to reach a peak (88% of ganglion cells) at E8, and finally declined (59% at E12, 51% after hatching). The fall of the SP-like-positive DRG cells resulted from two concomitant events affecting a subset of small B-neurons: a loss of neuronal SP-like immunoreactivity and cell death. After one hindlimb resection at an early (E6) or late (E12) stage of development (that is before or after establishment of peripheral connections), the DRG were examined 6 days later. In both cases, a drastic neuronal death occurred in the ispilateral DRG. However, the resection at E6 did not change the percentage of SP-like-positive neurons, while the resection at E12 severely reduced the proportion of SP-like-immunoreactive DRG cells (25%). In conclusion, connections established between DRG and peripheral target tissues not only promote the survival of sensory neurons, but also control the maintenance of SP-like-expression. Factors issued from innervated targets such as NGF would support the survival of SP-expressing DRG cells and enhance their SP content while other factors present in skeletal muscle or skin would hinder SP expression and therefore lower SP levels in a subset of primary sensory neurons.

Oral Antibiotics for Fever in Low-Risk Neutropenic Patients With Cancer: A Double-Blind, Randomized, Multicenter Trial Comparing Single Daily Moxifloxacin With Twice Daily Ciprofloxacin Plus Amoxicillin/Clavulanic Acid Combination Therapy--EORTC Infectious Diseases Group Trial XV.

PURPOSE This double-blind, multicenter trial compared the efficacy and safety of a single daily oral dose of moxifloxacin with oral combination therapy in low-risk febrile neutropenic patients with cancer. PATIENTS AND METHODS Inclusion criteria were cancer, febrile neutropenia, low risk of complications as predicted by a Multinational Association for Supportive Care in Cancer (MASCC) score > 20, ability to swallow, and ≤ one single intravenous dose of empiric antibiotic therapy before study drug treatment initiation. Early discharge was encouraged when a set of predefined criteria was met. Patients received either moxifloxacin (400 mg once daily) monotherapy or oral ciprofloxacin (750 mg twice daily) plus amoxicillin/clavulanic acid (1,000 mg twice daily). The trial was designed to show equivalence of the two drug regimens in terms of therapy success, defined as defervescence and improvement in clinical status during study drug treatment (< 10% difference). Results Among the 333 patients evaluated in an intention-to-treat analysis, therapy success was observed in 80% of the patients administered moxifloxacin and in 82% of the patients administered combination therapy (95% CI for the difference, -10% to 8%, consistent with equivalence). Minor differences in tolerability, safety, and reasons for failure were observed. More than 50% of the patients in the two arms were discharged on protocol therapy, with 5% readmissions among those in either arm. Survival was similar (99%) in both arms. CONCLUSION Monotherapy with once daily oral moxifloxacin is efficacious and safe in low-risk febrile neutropenic patients identified with the help of the MASCC scoring system, discharged early, and observed as outpatients.

Propofol anesthesia impairs the maturation and survival of adult-born hippocampal neurons.

BACKGROUND: Adult neurogenesis occurs in the hippocampus of most mammals, including humans, and plays an important role in hippocampal-dependent learning. This process is highly regulated by neuronal activity and might therefore be vulnerable to anesthesia. In this article, the authors investigated this possibility by evaluating the impact of propofol anesthesia on mouse hippocampal neurons generated during adulthood, at two functionally distinct maturational stages of their development. METHODS: Adult-born hippocampal neurons were identified using the cell proliferation marker bromodeoxyuridine or a retroviral vector expressing the green fluorescent protein in dividing cells and their progenies. Eleven or 17 days after the labeling procedure, animals (n = 3-5 animals per group) underwent a 6-h-long propofol anesthesia. Twenty-one days after labeling, the authors analyzed the survival, differentiation, and morphologic maturation of adult-born neurons using confocal microscopy. RESULTS: Propofol impaired the survival and maturation of adult-born neurons in an age-dependent manner. Anesthesia induced a significant decrease in the survival of neurons that were 17 days old at the time of anesthesia, but not of neurons that were 11 days old. Similarly, propofol anesthesia significantly reduced the dendritic maturation of neurons generated 17 days before anesthesia, without interfering with the maturation of neurons generated 11 days before anesthesia. CONCLUSIONS: These results reveal that propofol impairs the survival and maturation of adult-born hippocampal neurons in a developmental stage-dependent manner in mice.

A single-base substitution within an intronic repetitive element causes dominant retinitis pigmentosa with reduced penetrance.

We report the study of a large American family displaying autosomal dominant retinitis pigmentosa with reduced penetrance, a form of hereditary retinal degeneration. Although the inheritance pattern and previous linkage mapping pointed to the involvement of the PRPF31 gene, extensive screening of all its exons and their boundaries failed in the past to reveal any mutation. In this work, we sequenced the entire PRPF31 genomic region by both the classical Sanger method and ultrahigh throughput (UHT) sequencing. Among the many variants identified, a single-base substitution (c.1374+654C>G) located deep within intron 13 and inside a repetitive DNA element was common to all patients and obligate asymptomatic carriers. This change created a new splice donor site leading to the synthesis of two mutant PRPF31 isoforms, degraded by nonsense-mediated mRNA decay. As a consequence, amounts of PRPF31 mRNA derived from the mutant allele were very reduced, with no evidence of mutant proteins being synthesized. Our results indicate that c.1374+654C>G causes retinitis pigmentosa via haploinsufficiency, similar to the vast majority of PRPF31 mutations described so far. We discuss the potential of UHT sequencing technologies in mutation screening and the continued identification of pathogenic splicing mutations buried deep within intronic regions.

Waveform inversion of crosshole georadar data: influence of source wavelet variability and the suitability of a single wavelet assumption

Waveform-based tomographic imaging of crosshole georadar data is a powerful method to investigate the shallow subsurface because of its ability to provide images of electrical properties in near-surface environments with unprecedented spatial resolution. A critical issue with waveform inversion is the a priori unknown source signal. Indeed, the estimation of the source pulse is notoriously difficult but essential for the effective application of this method. Here, we explore the viability and robustness of a recently proposed deconvolution-based procedure to estimate the source pulse during waveform inversion of crosshole georadar data, where changes in wavelet shape with location as a result of varying near-field conditions and differences in antenna coupling may be significant. Specifically, we examine whether a single, average estimated source current function can adequately represent the pulses radiated at all transmitter locations during a crosshole georadar survey, or whether a separate source wavelet estimation should be performed for each transmitter gather. Tests with synthetic and field data indicate that remarkably good tomographic reconstructions can be obtained using a single estimated source pulse when moderate to strong variability exists in the true source signal with antenna location. Only in the case of very strong variability in the true source pulse are tomographic reconstructions clearly improved by estimating a different source wavelet for each transmitter location.

Differential vulnerability of neurochemically identified subpopulations of retinal neurons in a monkey model of glaucoma.

The vulnerability of subpopulations of retinal neurons delineated by their content of cytoskeletal or calcium-binding proteins was evaluated in the retinas of cynomolgus monkeys in which glaucoma was produced with an argon laser. We quantitatively compared the number of neurons containing either neurofilament (NF) protein, parvalbumin, calbindin or calretinin immunoreactivity in central and peripheral portions of the nasal and temporal quadrants of the retina from glaucomatous and fellow non-glaucomatous eyes. There was no significant difference between the proportion of amacrine, horizontal and bipolar cells labeled with antibodies to the calcium-binding proteins comparing the two eyes. NF triplet immunoreactivity was present in a subpopulation of retinal ganglion cells, many of which, but not all, likely correspond to large ganglion cells that subserve the magnocellular visual pathway. Loss of NF protein-containing retinal ganglion cells was widespread throughout the central (59-77% loss) and peripheral (96-97%) nasal and temporal quadrants and was associated with the loss of NF-immunoreactive optic nerve fibers in the glaucomatous eyes. Comparison of counts of NF-immunoreactive neurons with total cell loss evaluated by Nissl staining indicated that NF protein-immunoreactive cells represent a large proportion of the cells that degenerate in the glaucomatous eyes, particularly in the peripheral regions of the retina. Such data may be useful in determining the cellular basis for sensitivity to this pathologic process and may also be helpful in the design of diagnostic tests that may be sensitive to the loss of the subset of NF-immunoreactive ganglion cells.

Fuel metabolism during exercise in euglycaemia and hyperglycaemia in patients with type 1 diabetes mellitus--a prospective single-blinded randomised crossover trial.

Aims/hypothesis We assessed systemic and local muscle fuel metabolism during aerobic exercise in patients with type I diabetes at euglycaemia and hyperglycaemia with identical insulin levels.Methods This was a single-blinded randomised crossover study at a university diabetes unit in Switzerland. We studied seven physically active men with type I diabetes (mean +/- SEM age 33.5 +/- 2.4 years, diabetes duration 20.1 +/- 3.6 years, HbA(1c) 6.7 +/- 0.2% and peak oxygen uptake [VO2peak] 50.3 +/- 4.5 ml min(-1) kg(-1)). Men were studied twice while cycling for 120 min at 55 to 60% of VO2peak, with a blood glucose level randomly set either at 5 or 11 mmol/l and identical insulinaemia. The participants were blinded to the glycaemic level; allocation concealment was by opaque, sealed envelopes. Magnetic resonance spectroscopy was used to quantify intramyocellular glycogen and lipids before and after exercise. Indirect calorimetry and measurement of stable isotopes and counter-regulatory hormones complemented the assessment of local and systemic fuel metabolism.Results The contribution of lipid oxidation to overall energy metabolism was higher in euglycaemia than in hyperglycaemia (49.4 +/- 4.8 vs 30.6 +/- 4.2%; p<0.05). Carbohydrate oxidation accounted for 48.2 +/- 4.7 and 66.6 +/- 4.2% of total energy expenditure in euglycaemia and hyperglycaemia, respectively (p<0.05). The level of intramyocellular glycogen before exercise was higher in hyperglycaemia than in euglycaemia (3.4 +/- 0.3 vs 2.7 +/- 0.2 arbitrary units [AU]; p<0.05). Absolute glycogen consumption tended to be higher in hyperglycaemia than in euglycaemia (1.3 +/- 0.3 vs 0.9 +/- 0.1 AU). Cortisol and growth hormone increased more strongly in euglycaemia than in hyperglycaemia (levels at the end of exercise 634 52 vs 501 +/- 32 nmol/l and 15.5 +/- 4.5 vs 7.4 +/- 2.0 ng/ml, respectively; p<0.05).Conclusions/interpretation Substrate oxidation in type I diabetic patients performing aerobic exercise in euglycaemia is similar to that in healthy individuals revealing a shift towards lipid oxidation during exercise. In hyperglycaemia fuel metabolism in these patients is dominated by carbohydrate oxidation. Intramyocellular glycogen was not spared in hyperglycaemia.

Genetic manipulation of adult-born hippocampal neurons rescues memory in a mouse model of Alzheimer's disease.

In adult mammals, neural progenitors located in the dentate gyrus retain their ability to generate neurons and glia throughout lifetime. In rodents, increased production of new granule neurons is associated with improved memory capacities, while decreased hippocampal neurogenesis results in impaired memory performance in several memory tasks. In mouse models of Alzheimer's disease, neurogenesis is impaired and the granule neurons that are generated fail to integrate existing networks. Thus, enhancing neurogenesis should improve functional plasticity in the hippocampus and restore cognitive deficits in these mice. Here, we performed a screen of transcription factors that could potentially enhance adult hippocampal neurogenesis. We identified Neurod1 as a robust neuronal determinant with the capability to direct hippocampal progenitors towards an exclusive granule neuron fate. Importantly, Neurod1 also accelerated neuronal maturation and functional integration of new neurons during the period of their maturation when they contribute to memory processes. When tested in an APPxPS1 mouse model of Alzheimer's disease, directed expression of Neurod1 in cycling hippocampal progenitors conspicuously reduced dendritic spine density deficits on new hippocampal neurons, to the same level as that observed in healthy age-matched control animals. Remarkably, this population of highly connected new neurons was sufficient to restore spatial memory in these diseased mice. Collectively our findings demonstrate that endogenous neural stem cells of the diseased brain can be manipulated to become new neurons that could allow cognitive improvement.

Nanopore detection of single molecule RNAP-DNA transcription complex.

In the past decade, a number of single-molecule methods have been developed with the aim of investigating single protein and nucleic acid interactions. For the first time we use solid-state nanopore sensing to detect a single E. coli RNAP-DNA transcription complex and single E. coli RNAP enzyme. On the basis of their specific conductance translocation signature, we can discriminate and identify between those two types of molecular translocations and translocations of bare DNA. This opens up a new perspectives for investigating transcription processes at the single-molecule level.