The sterile insect technique (SIT) is an environmentally safe and proven technology to suppress wild populations. To further advance its utility, a novel CRISPR-based technology termed precision ...guided SIT (pgSIT) is described. PgSIT mechanistically relies on a dominant genetic technology that enables simultaneous sexing and sterilization, facilitating the release of eggs into the environment ensuring only sterile adult males emerge. Importantly, for field applications, the release of eggs will eliminate burdens of manually sexing and sterilizing males, thereby reducing overall effort and increasing scalability. Here, to demonstrate efficacy, we systematically engineer multiple pgSIT systems in Drosophila which consistently give rise to 100% sterile males. Importantly, we demonstrate that pgSIT-generated sterile males are fit and competitive. Using mathematical models, we predict pgSIT will induce substantially greater population suppression than can be achieved by currently-available self-limiting suppression technologies. Taken together, pgSIT offers to potentially transform our ability to control insect agricultural pests and disease vectors.
The demand for hydrogen over the coming decade is expected to grow for both traditional uses (ammonia, methanol, refinery) and running fuel cells. At least in the near future, this thirst for ...hydrogen will be quenched primarily through the reforming of fossil fuels. However, reforming fossil fuels emits huge amounts of carbon dioxide. One approach to reduce carbon dioxide emissions, which is considered first in this review, is to apply reforming methods to alternative renewable materials. Such materials might be derived from plant crops, agricultural residues, woody biomass, etc. Clean biomass is a proven source of renewable energy that is already used for generating heat, electricity, and liquid transportation fuels. Clean biomass and biomass-derived precursors such as ethanol and sugars are appropriate precursors for producing hydrogen through different conversion strategies. Virtually no net greenhouse gas emissions result because a natural cycle is maintained, in which carbon is extracted from the atmosphere during plant growth and released during hydrogen production. The second option explored here is hydrogen production from water splitting by means of the photons in the visible spectrum. The sun provides silent and precious energy that is distributed fairly evenly all over the earth. However, its tremendous potential as a clean, safe and economical energy source cannot be exploited unless it is accumulated or converted into more useful forms of energy. Finally, this review discusses the use of semiconductors, more specifically CdS and CdS-based semiconductors, which are able to absorb photons in the visible region of the spectrum. The energy stored within a semiconductor as electronic energy (electrons and holes) can be used to split water molecules by simultaneous reactions into H2 and O2. This conversion of solar energy into a clean fuel (H2) is perhaps the greatest challenge for scientists in the 21st century.
Prunus spp. are affected by a large number of viruses, causing significant economic losses through either direct or indirect damage, which results in reduced yield and fruit quality. Among these ...viruses, members of the genus Ilarvirus (isometric labile ringspot viruses) occupy a significant position due to their distribution worldwide. Although symptoms caused by these types of viruses were reported early in the last century, their molecular characterization was not achieved until the 1990s, much later than for other agronomically relevant viruses. This was mainly due to the characteristic liability of virus particles in tissue extracts. In addition, ilarviruses, together with Alfalfa mosaic virus, are unique among plant viruses in that they require a few molecules of the coat protein in the inoculum in order to be infectious, a phenomenon known as genome activation. Another factor that has made the study of this group of viruses difficult is that infectious clones have been obtained only for the type member of the genus, Tobacco streak virus. Four ilarviruses, Prunus necrotic ringspot virus, Prune dwarf virus, Apple mosaic virus, and American plum line pattern virus, are pathogens of the main cultivated fruit trees. As stated in the 9th Report of the International Committee on Taxonomy of Viruses, virions of this genus are "unpromising subjects for the raising of good antisera." With the advent of molecular approaches for their detection and characterization, it has been possible to get a more precise view of their prevalence and genome organization. This review updates our knowledge on the incidence, genome organization and expression, genetic diversity, modes of transmission, and diagnosis, as well as control of this peculiar group of viruses affecting fruit trees.
We introduce selective area grown hybrid InAs/Al nanowires based on molecular beam epitaxy, allowing arbitrary semiconductor-superconductor networks containing loops and branches. Transport reveals a ...hard induced gap and unpoisoned 2e-periodic Coulomb blockade, with temperature dependent 1e features in agreement with theory. Coulomb peak spacing in parallel magnetic field displays overshoot, indicating an oscillating discrete near-zero subgap state consistent with device length. Finally, we investigate a loop network, finding strong spin-orbit coupling and a coherence length of several microns. These results demonstrate the potential of this platform for scalable topological networks among other applications.
Abstract
Motivation
Molecular profiling techniques have evolved to single-cell assays, where dense molecular profiles are screened simultaneously for each cell in a population. High-throughput ...single-cell experiments from a heterogeneous population of cells can be experimentally and computationally sorted as a sequence of samples pseudo-temporally ordered samples. The analysis of these datasets, comprising a large number of samples, has the potential to uncover the dynamics of the underlying regulatory programmes.
Results
We present a novel approach for modelling and inferring gene regulatory networks from high-throughput time series and pseudo-temporally sorted single-cell data. Our method is based on a first-order autoregressive moving-average model and it infers the gene regulatory network within a variational Bayesian framework. We validate our method with synthetic data and we apply it to single cell qPCR and RNA-Seq data for mouse embryonic cells and hematopoietic cells in zebra fish.
Availability and implementation
The method presented in this article is available at https://github.com/mscastillo/GRNVBEM.
The main objective of this study was to list and compare the advantages and disadvantages of different methodologies to modify the surface of activated carbons (ACs) for their application as ...adsorbents to remove organic and inorganic pollutants from aqueous phase. These methodologies have been categorized into four broad groups: oxidation, sulfuration, ammonification, and coordinated ligand anchorage. Numerous investigations into the removal of metals from water have modified carbon surfaces to increase their content of acidic surface functional groups by using H2O2, O3 and HNO3. Because these treatments can reduce the AC surface area, researchers are seeking alternative methods to modify and/or create surface functional groups without the undesirable effect of pore blockage. The nitrogenation or sulfuration of the AC surface can increase its basicity favoring the adsorption of organic compounds. The introduction of nitrogen or sulfur complexes on the carbon surface increases the surface polarity and, therefore, the specific interaction with polar pollutants. Different coordinated ligands have also been used to modify ACs, showing that coordinated ligand anchorage on the AC surface modifies its textural and chemical properties, but research to date has largely focused on the use of these modified materials to remove heavy metals from water by complexes formation.
Background
Despite the socioeconomic importance of allergic rhinitis (AR), very few prospective studies have been performed under conditions of clinical practice and with a sufficiently long ...observation period outside the clinical trial scenario. We prospectively estimated the direct and indirect costs of AR in patients attending specialized clinics in Spain.
Methods
Patients were recruited at random from allergy outpatient clinics in 101 health centers throughout Spain over 12 months. We performed a multicenter, observational, prospective study under conditions of clinical practice. We analyzed direct costs from a funder perspective (healthcare costs) and from a societal perspective (healthcare and non–healthcare costs). Indirect costs (absenteeism and presenteeism productivity lost in the workplace) were also calculated. The cost of treating conjunctivitis was evaluated alongside that of AR.
Results
The total mean cost of AR per patient‐year (n = 498) was €2326.70 (direct, €553.80; indirect, €1772.90). Direct costs were significantly higher in women (€600.34 vs €484.46, P = 0.02). Total costs for intermittent AR were significantly lower than for persistent AR (€1484.98 vs €2655.86, P < 0.001). Total indirect costs reached €1772.90 (presenteeism, €1682.71; absenteeism, €90.19). The direct costs of AR in patients with intermittent asthma (€507.35) were lower than in patients with mild‐persistent asthma (€719.07) and moderate‐persistent asthma (€798.71) (P = 0.006).
Conclusions
The total cost of AR for society is considerable. Greater frequency of symptoms and more severe AR are associated with higher costs. Indirect costs are almost threefold direct costs, especially in presenteeism. A reduction in presenteeism would generate considerable savings for society.
Abstract Parkinson's disease (PD) is diagnosed when striatal dopamine (DA) loss exceeds a certain threshold and the cardinal motor features become apparent. The presymptomatic compensatory mechanisms ...underlying the lack of motor manifestations despite progressive striatal depletion are not well understood. Most animal models of PD involve the induction of a severe dopaminergic deficit in an acute manner, which departs from the typical, chronic evolution of PD in humans. We have used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administered to monkeys via a slow intoxication protocol to produce a more gradual development of nigral lesion. Twelve control and 38 MPTP-intoxicated monkeys were divided into four groups. The latter included monkeys who were always asymptomatic, monkeys who recovered after showing mild parkinsonian signs, and monkeys with stable, moderate and severe parkinsonism. We found a close correlation between cell loss in the substantia nigra pars compacta (SNc) and striatal dopaminergic depletion and the four motor states. There was an overall negative correlation between the degree of parkinsonism (Kurlan scale) and in vivo PET (18 F-DOPA Ki and11 C-DTBZ binding potential), as well as with TH-immunoreactive cell counts in SNc, striatal dopaminergic markers (TH, DAT and VMAT2) and striatal DA concentration. This intoxication protocol permits to establish a critical threshold of SNc cell loss and dopaminergic innervation distinguishing between the asymptomatic and symptomatic parkinsonian stages. Compensatory changes in nigrostriatal dopaminergic activity occurred in the recovered and parkinsonian monkeys when DA depletion was at least 88% of control, and accordingly may be considered too late to explain compensatory mechanisms in the early asymptomatic period. Our findings suggest the need for further exploration of the role of non-striatal mechanisms in PD prior to the development of motor features.
The nitrogen cycle has been expanded with the recent discovery of
Nitrospira
strains that can conduct complete ammonium oxidation (commamox). Their importance in the nitrogen cycle within engineered ...ecosystems has not yet been analyzed. In this research, the community structure of the
Bacteria
domain of six full-scale activated sludge systems and three autotrophic nitrogen removal systems in the Netherlands and China has been investigated through
tag
-454-pyrosequencing. The phylogenetic analyses conducted in the present study showed that just a few of the
Nitrospira
sequences found in the bioreactors were comammox. Multivariate redundancy analysis of nitrifying genera showed an outcompetition of
Nitrosomonas
and non-comammox
Nitrospira
. Operational data from the bioreactors suggested that comammox could be favored at low temperature, low nitrogen substrate, and high dissolved oxygen. The non-ubiquity and low relative abundance of comammox in full-scale bioreactors suggested that this phylotype is not very relevant in the nitrogen cycle in wastewater treatment plants.
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