20,821 research outputs found
De Novo Occurrence of a Variant in ARL3 and Apparent Autosomal Dominant Transmission of Retinitis Pigmentosa.
BackgroundRetinitis pigmentosa is a phenotype with diverse genetic causes. Due to this genetic heterogeneity, genome-wide identification and analysis of protein-altering DNA variants by exome sequencing is a powerful tool for novel variant and disease gene discovery. In this study, exome sequencing analysis was used to search for potentially causal DNA variants in a two-generation pedigree with apparent dominant retinitis pigmentosa.MethodsVariant identification and analysis of three affected members (mother and two affected offspring) was performed via exome sequencing. Parental samples of the index case were used to establish inheritance. Follow-up testing of 94 additional retinitis pigmentosa pedigrees was performed via retrospective analysis or Sanger sequencing.Results and conclusionsA total of 136 high quality coding variants in 123 genes were identified which are consistent with autosomal dominant disease. Of these, one of the strongest genetic and functional candidates is a c.269A>G (p.Tyr90Cys) variant in ARL3. Follow-up testing established that this variant occurred de novo in the index case. No additional putative causal variants in ARL3 were identified in the follow-up cohort, suggesting that if ARL3 variants can cause adRP it is an extremely rare phenomenon
Direct Band Gap Gallium Antimony Phosphide (GaSb\u3csub\u3ex\u3c/sub\u3eP\u3csub\u3e1-x\u3c/sub\u3e) Alloys
Here, we report direct band gap transition for Gallium Phosphide (GaP) when alloyed with just 1–2 at% antimony (Sb) utilizing both density functional theory based computations and experiments. First principles density functional theory calculations of GaSbxP1−x alloys in a 216 atom supercell configuration indicate that an indirect to direct band gap transition occurs at x = 0.0092 or higher Sb incorporation into GaSbxP1−x. Furthermore, these calculations indicate band edge straddling of the hydrogen evolution and oxygen evolution reactions for compositions ranging from x = 0.0092 Sb up to at least x = 0.065 Sb making it a candidate for use in a Schottky type photoelectrochemical water splitting device. GaSbxP1−x nanowires were synthesized by reactive transport utilizing a microwave plasma discharge with average compositions ranging from x = 0.06 to x = 0.12 Sb and direct band gaps between 2.21 eV and 1.33 eV. Photoelectrochemical experiments show that the material is photoactive with p-type conductivity. This study brings attention to a relatively uninvestigated, tunable band gap semiconductor system with tremendous potential in many fields
Assessing the Gene Content of the Megagenome: Sugar Pine (Pinus lambertiana).
Sugar pine (Pinus lambertiana Douglas) is within the subgenus Strobus with an estimated genome size of 31 Gbp. Transcriptomic resources are of particular interest in conifers due to the challenges presented in their megagenomes for gene identification. In this study, we present the first comprehensive survey of the P. lambertiana transcriptome through deep sequencing of a variety of tissue types to generate more than 2.5 billion short reads. Third generation, long reads generated through PacBio Iso-Seq have been included for the first time in conifers to combat the challenges associated with de novo transcriptome assembly. A technology comparison is provided here to contribute to the otherwise scarce comparisons of second and third generation transcriptome sequencing approaches in plant species. In addition, the transcriptome reference was essential for gene model identification and quality assessment in the parallel project responsible for sequencing and assembly of the entire genome. In this study, the transcriptomic data were also used to address questions surrounding lineage-specific Dicer-like proteins in conifers. These proteins play a role in the control of transposable element proliferation and the related genome expansion in conifers
The nature of domain walls in ultrathin ferromagnets revealed by scanning nanomagnetometry
The recent observation of current-induced domain wall (DW) motion with large
velocity in ultrathin magnetic wires has opened new opportunities for
spintronic devices. However, there is still no consensus on the underlying
mechanisms of DW motion. Key to this debate is the DW structure, which can be
of Bloch or N\'eel type, and dramatically affects the efficiency of the
different proposed mechanisms. To date, most experiments aiming to address this
question have relied on deducing the DW structure and chirality from its motion
under additional in-plane applied fields, which is indirect and involves strong
assumptions on its dynamics. Here we introduce a general method enabling
direct, in situ, determination of the DW structure in ultrathin ferromagnets.
It relies on local measurements of the stray field distribution above the DW
using a scanning nanomagnetometer based on the Nitrogen-Vacancy defect in
diamond. We first apply the method to a Ta/Co40Fe40B20(1 nm)/MgO magnetic wire
and find clear signature of pure Bloch DWs. In contrast, we observe left-handed
N\'eel DWs in a Pt/Co(0.6 nm)/AlOx wire, providing direct evidence for the
presence of a sizable Dzyaloshinskii-Moriya interaction (DMI) at the Pt/Co
interface. This method offers a new path for exploring interfacial DMI in
ultrathin ferromagnets and elucidating the physics of DW motion under current.Comment: Main text and Supplementary Information, 33 pages and 12 figure
Proper motions of the HH1 jet
We describe a new method for determining proper motions of extended objects,
and a pipeline developed for the application of this method. We then apply this
method to an analysis of four epochs of [S~II] HST images of the HH~1 jet
(covering a period of ~yr).
We determine the proper motions of the knots along the jet, and make a
reconstruction of the past ejection velocity time-variability (assuming
ballistic knot motions). This reconstruction shows an "acceleration" of the
ejection velocities of the jet knots, with higher velocities at more recent
times. This acceleration will result in an eventual merging of the knots in
~yr and at a distance of from the outflow source, close to
the present-day position of HH~1.Comment: 12 pages, 8 figure
Fisheries wastewater as a sustainable media for the production of algae-based products
Colombian intensive fish production is concentrated mainly in the departments of the Andean Region, Amazon, and Orinoquía. These systems were characterized for being exploited mainly by family farming nuclei, which are dedicated exclusively to breeding and others with mixed systems. Currently, the sustainable development of this economic line depends on two factors: global warming and the consumption of resources (energy, fresh water, and protein). The rapid growth of this socio-economic line has led to the development of 3 critical restrictions: the demand for food for fish production, the high volume of fresh water needed and the high concentration of wastewater which must be disposed of safely. Sewage from closed fish farming systems has high levels of nitrogen and inorganic phosphorus dissolved in the systems. The primary responsibility for these high contents is the feed which contributes to the sustained increase in the concentration of organic waste and toxic compounds in aquatic systems. To make use of this wastewater, the use of these as a culture medium for microalgal production has been studied in order to generate metabolites of industrial interest from a low-cost culture medium. In this work, the necessary culture conditions for the biomass production of Scenedesmus obliquus, Chlorella vulgaris, Spirulina maxima, and Oscillatoria sp. in fish farming wastewater to produce pigments and total biomass are evaluated. The wastewater was obtained from an intensive fish farming company in El Zulia (Norte de Santander, Colombia). The medium was UV-sterilized (4 Lamps of 15W, 5 minutes). In order to optimize the production of biomass and pigments, the wastewater was adjusted with the addition of nitrogen, phosphorus, and carbon (K2HPO4 + NaNO3 + NaHCO3) According to the results, the residual water enriched with K2HPO4, NaNO3 and NaHCO3 presented the best culture conditions for obtaining carotenoids (in C. vulgaris and S. obliquus with values of 2.6 and 1.7% p/p respectively) and Phycobiliproteins in Spirulina maxima and Oscillatoria sp (10.9 and 11% p/p respectively). These results allow concluding that the residual water of fish systems is outlined as a suitable culture medium that can be used to produce metabolites of interest. Also, this culture medium must be enriched in order to increase the productivity of the system
Three body systems with strangeness and exotic systems
We report on four 's and three 's, in the 1500 - 1800 MeV
region, as two meson - one baryon S-wave resonances found by solving
the Faddeev equations in the coupled channel approach, which can be associated
to the existing = -1, low lying baryon resonances. On the
other hand we also report on a new, hidden strangeness state, mostly made
of , with mass around 1920 MeV, which we think could be
responsible for the peak seen in the around this
energy. Finally we address a very novel topic in which we show how few body
systems of several mesons can be produced, with their spins aligned up
to J=6, and how these states found theoretically can be associated to several
known mesons with spins J=2,3,4,5,6.Comment: Talk at the 21st European Conference on Few Body Problems in Physics,
Salamanca, Sep. 201
The 2500 yr long paleoseismological record of the Hazar Lake, East Anatolian fault, Turkey
Understanding the Irregularity of Seismic Cycles: A Case Study in Turke
Glucose-lactate metabolic cooperation in cancer: insights from a spatial mathematical model and implications for targeted therapy
A recent study has hypothesised a glucose–lactate metabolic symbiosis between adjacent hypoxic and oxygenated regions of a developing tumour, and proposed a treatment strategy to target this symbiosis. However, in vivo experimental support remains inconclusive. Here we develop a minimal spatial mathematical model of glucose–lactate metabolism to examine, in principle, whether metabolic symbiosis is plausible in human tumours, and to assess the potential impact of inhibiting it. We find that symbiosis is a robust feature of our model system—although on the length scale at which oxygen supply is diffusion-limited, its occurrence requires very high cellular metabolic activity—and that necrosis in the tumour core is reduced in the presence of symbiosis. Upon simulating therapeutic inhibition of lactate uptake, we predict that targeted treatment increases the extent of tissue oxygenation without increasing core necrosis. The oxygenation effect is correlated strongly with the extent of wild-type hypoxia and only weakly with wild-type symbiotic behaviour, and therefore may be promising for radiosensitisation of hypoxic, lactate-consuming tumours even if they do not exhibit a spatially well-defined symbiosis. Finally, we conduct in vitro experiments on the U87 glioblastoma cell line to facilitate preliminary speculation as to where highly malignant tumours might fall in our parameter space, and find that these experiments suggest a weakly symbiotic regime for U87 cells, thus raising the new question of what relationship might exist between symbiosis and tumour malignancy
Enhancement of metabolite production in high-altitude microalgal strains by optimized C/N/P ratio
This study evaluated the role of C/N/P in the increase in the synthesis of carbohydrates, proteins, and lipids in two high-mountain strains of algae (Chlorella sp. UFPS019 and Desmodesmus sp. UFPS021). Three carbon sources (sodium acetate, sodium carbonate, and sodium bicarbonate), and the sources of nitrogen (NaNO3) and phosphate (KH2PO4 and K2HPO4) were analyzed using a surface response (3 factors, 2 levels). In Chlorella sp. UFPS019, the optimal conditions to enhance the synthesis of carbohydrates were high sodium carbonate content (3.53 g/L), high KH2PO4 and K2HPO4 content (0.06 and 0.14 g/L, respectively), and medium-high NaNO3 (0.1875 g/L). In the case of lipids, a high concentration of sodium acetate (1.19 g/L) coupled with high KH2PO4 and K2HPO4 content (0.056 and 0.131 g/L, respectively) and a low concentration of NaNO3 (0.075 g/L) drastically induced the synthesis of lipids. In the case of Desmodesmus sp. UFPS021, the protein content was increased using high sodium acetate (2 g/L), high KH2PO4 and K2HPO4 content (0.056 and 0.131 g/L, respectively), and high NaNO3 concentration (0.25 g/L). These results demonstrate that the correct adjustment of the C/N/P ratio can enhance the capacity of high-mountain strains of algae to produce high concentrations of carbohydrates, proteins, and lipids
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