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1.
Phytopathology ; 114(7): 1542-1553, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38619562

ABSTRACT

Spot form net blotch, caused by Pyrenophora teres f. maculata, is a significant necrotrophic disease of barley that spread worldwide in the twentieth century. Genetic relationships were analyzed to determine the diversity, survival, and dispersal of a diverse collection of 346 isolates from Australia, Southern Africa, North America, Asia Minor, and Europe. The results, based on genome-wide DArTseq data, indicated that isolates from Turkey were the most differentiated with regional sub-structuring, together with individuals closely related to geographically distant genotypes. Elsewhere, population subdivision related to country of origin was evident, although low levels of admixturing was found that may represent rare genotypes or migration from unsampled populations. Canadian isolates were the next most diverged, and Australian and South African the most closely related. With the exception of Turkish isolates, multiple independent Cyp51A mutation events (which confer insensitivity to demethylation inhibitor fungicides) between countries and within regions was evident, with strong selection for a transposable element insertion at the 3' end of the promoter and counterselection elsewhere. Individuals from Western Australia shared genomic regions and Cyp51A haplotypes with South African isolates, suggesting a recent common origin. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Subject(s)
Ascomycota , Hordeum , Plant Diseases , Hordeum/microbiology , Plant Diseases/microbiology , Ascomycota/genetics , Ascomycota/isolation & purification , Genetic Variation , Genotype , Haplotypes , Australia , Mutation , Phylogeny
2.
Sci Adv ; 10(11): eadl1814, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38478618

ABSTRACT

Quantum optical technologies promise advances in sensing, computing, and communication. A key resource is squeezed light, where quantum noise is redistributed between optical quadratures. We introduce a monolithic, chip-scale platform that exploits the χ(2) nonlinearity of a thin-film lithium niobate (TFLN) resonator device to efficiently generate squeezed states of light. Our system integrates all essential components-except for the laser and two detectors-on a single chip with an area of one square centimeter, reducing the size, operational complexity, and power consumption associated with conventional setups. Using the balanced homodyne measurement subsystem that we implemented on the same chip, we measure a squeezing of 0.55 decibels and an anti-squeezing of 1.55 decibels. We use 20 milliwatts of input power to generate the parametric oscillator pump field by using second harmonic generation on the same chip. Our work represents a step toward compact and efficient quantum optical systems posed to leverage the rapid advances in integrated nonlinear and quantum photonics.

3.
Nature ; 627(8002): 95-100, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38448697

ABSTRACT

Optical frequency combs have revolutionized precision measurement, time-keeping and molecular spectroscopy1-7. A substantial effort has developed around 'microcombs': integrating comb-generating technologies into compact photonic platforms5,7-9. Current approaches for generating these microcombs involve either the electro-optic10 or Kerr mechanisms11. Despite rapid progress, maintaining high efficiency and wide bandwidth remains challenging. Here we introduce a previously unknown class of microcomb-an integrated device that combines electro-optics and parametric amplification to yield a frequency-modulated optical parametric oscillator (FM-OPO). In contrast to the other solutions, it does not form pulses but maintains operational simplicity and highly efficient pump power use with an output resembling a frequency-modulated laser12. We outline the working principles of our device and demonstrate it by fabricating the complete optical system in thin-film lithium niobate. We measure pump-to-comb internal conversion efficiency exceeding 93% (34% out-coupled) over a nearly flat-top spectral distribution spanning about 200 modes (over 1 THz). Compared with an electro-optic comb, the cavity dispersion rather than loss determines the FM-OPO bandwidth, enabling broadband combs with a smaller radio-frequency modulation power. The FM-OPO microcomb offers robust operational dynamics, high efficiency and broad bandwidth, promising compact precision tools for metrology, spectroscopy, telecommunications, sensing and computing.

4.
Nat Commun ; 14(1): 3355, 2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37291141

ABSTRACT

The quantum noise of light, attributed to the random arrival time of photons from a coherent light source, fundamentally limits optical phase sensors. An engineered source of squeezed states suppresses this noise and allows phase detection sensitivity beyond the quantum noise limit (QNL). We need ways to use quantum light within deployable quantum sensors. Here we present a photonic integrated circuit in thin-film lithium niobate that meets these requirements. We use the second-order nonlinearity to produce a squeezed state at the same frequency as the pump light and realize circuit control and sensing with electro-optics. Using 26.2 milliwatts of optical power, we measure (2.7 ± 0.2)% squeezing and apply it to increase the signal-to-noise ratio of phase measurement. We anticipate that photonic systems like this, which operate with low power and integrate all of the needed functionality on a single die, will open new opportunities for quantum optical sensing.


Subject(s)
Oxides , Photons , Records , Signal-To-Noise Ratio
5.
Theor Appl Genet ; 136(1): 15, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36662256

ABSTRACT

KEY MESSAGE: Rhynchosporium commune is a globally devastating pathogen of barley. Wild and landrace barley are underutilized, however, contain an abundance of loci that can be used as potential sources of resistance. Rhynchosporium commune, the causal agent of the disease scald or leaf blotch of barley, is a hemibiotrophic fungal pathogen of global importance, responsible for yield losses ranging from 30 to 40% on susceptible varieties. To date, over 150 resistance loci have been characterized in barley. However, due to the suspected location of the R. commune host jump in Europe, European germplasm has been the primary source used to screen for R. commune resistance leaving wild (Hordeum spontaneum) and landrace (H. vulgare) barley populations from the center of origin largely underutilized. A diverse population consisting of 94 wild and 188 barley landraces from Turkey were genotyped using PCR-GBS amplicon sequencing and screened with six Turkish R. commune isolates. The isolates were collected from distinct geographic regions of Turkey with two from the Aegean region, two from central Turkey and two from the Fertile Crescent region. The data set was utilized for association mapping analysis with a total of 21 loci identified, of which 12 were novel, indicating that these diverse primary barley gene pools contain an abundance of novel R. commune resistances that could be utilized for resistance breeding.


Subject(s)
Ascomycota , Hordeum , Hordeum/genetics , Hordeum/microbiology , Turkey , Plant Breeding , Plant Diseases/genetics , Plant Diseases/microbiology , Disease Resistance/genetics
6.
J Plant Physiol ; 279: 153839, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36370615

ABSTRACT

Pyrenophora teres f. maculata (Ptm) is a fungal pathogen that causes the spot form of net blotch on barley and leads to economic losses in many of the world's barley-growing regions. Isolates of Ptm exhibit varying levels of aggressiveness that result in quantifiable changes in the severity of the disease. Previous research on plant-pathogen interactions has shown that such divergence is reflected in the proteome and secretome of the pathogen, with certain classes of proteins more prominent in aggressive isolates. Here we have made a detailed comparative analysis of the secretomes of two Ptm isolates, GPS79 and E35 (highly and mildly aggressive, respectively) using a proteomics-based approach. The secretomes were obtained in vitro using media amended with barley leaf sections. Secreted proteins therein were harvested, digested with trypsin, and fractionated offline by HPLC prior to LC-MS in a high-resolution instrument to obtain deep coverage of the proteome. The subsequent analysis used a label-free quantitative proteomics approach with relative quantification of proteins based on precursor ion intensities. A total of 1175 proteins were identified, 931 from Ptm and 244 from barley. Further analysis revealed 160 differentially abundant proteins with at least a two-fold abundance difference between the isolates, with the most enriched in the aggressive GPS79 secretome. These proteins were mainly cell-wall (carbohydrate) degrading enzymes and peptidases, with some oxidoreductases and other pathogenesis-related proteins also identified, suggesting that aggressiveness is associated with an improved ability of GPS79 to overcome cell wall barriers and neutralize host defense responses.


Subject(s)
Ascomycota , Hordeum , Peptide Hydrolases , Proteome , Cell Wall
7.
Opt Express ; 30(13): 23177-23186, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-36225003

ABSTRACT

Integrated photonics operating at visible-near-infrared (VNIR) wavelengths offer scalable platforms for advancing optical systems for addressing atomic clocks, sensors, and quantum computers. The complexity of free-space control optics causes limited addressability of atoms and ions, and this remains an impediment on scalability and cost. Networks of Mach-Zehnder interferometers can overcome challenges in addressing atoms by providing high-bandwidth electro-optic control of multiple output beams. Here, we demonstrate a VNIR Mach-Zehnder interferometer on lithium niobate on sapphire with a CMOS voltage-level compatible full-swing voltage of 4.2 V and an electro-optic bandwidth of 2.7 GHz occupying only 0.35 mm2. Our waveguides exhibit 1.6 dB/cm propagation loss and our microring resonators have intrinsic quality factors of 4.4 × 105. This specialized platform for VNIR integrated photonics can open new avenues for addressing large arrays of qubits with high precision and negligible cross-talk.

8.
G3 (Bethesda) ; 11(11)2021 10 19.
Article in English | MEDLINE | ID: mdl-34849783

ABSTRACT

Unimproved landraces and wild relatives of crops are sources of genetic diversity that were lost post domestication in modern breeding programs. To tap into this rich resource, genome-wide association studies in large plant genomes have enabled the rapid genetic characterization of desired traits from natural landrace and wild populations. Wild barley (Hordeum spontaneum), the progenitor of domesticated barley (Hordeum vulgare), is dispersed across Asia and North Africa, and has co-evolved with the ascomycetous fungal pathogens Pyrenophora teres f. teres and P. teres f. maculata, the causal agents of the diseases net form of net blotch and spot form of net blotch, respectively. Thus, these wild and local adapted barley landraces from the region of origin of both the host and pathogen represent a diverse gene pool to identify new sources of resistance, due to millions of years of co-evolution. The barley-P. teres pathosystem is governed by complex genetic interactions with dominant, recessive, and incomplete resistances and susceptibilities, with many isolate-specific interactions. Here, we provide the first genome-wide association study of wild and landrace barley from the Fertile Crescent for resistance to both forms of P. teres. A total of 14 loci, four against P. teres f. maculata and 10 against P. teres f. teres, were identified in both wild and landrace populations, showing that both are genetic reservoirs for novel sources of resistance. We also highlight the importance of using multiple algorithms to both identify and validate additional loci.


Subject(s)
Hordeum , Ascomycota , Genome-Wide Association Study , Hordeum/genetics , Plant Breeding , Plant Diseases/genetics
10.
Lab Chip ; 19(22): 3815-3824, 2019 11 21.
Article in English | MEDLINE | ID: mdl-31638132

ABSTRACT

Droplet-based microfluidic systems require a precise control of droplet physical properties; hence, measuring the morphological properties of droplets is critical to obtain high sensitivity analysis. The ability to perform such measurements in real-time is another demand which has not been addressed yet. In this study, we used coplanar electrodes configured in the differential measurement mode for impedimetric measurement of size and velocity. To obtain the size of the droplets, detailed 3D finite element simulations of the system were performed. The interaction of the non-uniform electric field and the droplet was investigated. Electrode geometry optimization steps were described and design guideline rules were laid out. User-friendly software was developed for real-time observation of droplet length and velocity together with in situ statistical analysis results. A comparison between impedimetric and optical measurement tools is given. Finally, to illustrate the benefit of having real-time analysis, iDM was used to synthesize particles with a predefined monodispersity limit and to study the response times of syringe pump and pressure pump driven droplet generation devices. This analysis allows one to evaluate the 'warm-up' time for a droplet generator system, after which droplets reach the desired steady-state size required by the application of interest.

11.
Gels ; 4(3)2018 Aug 14.
Article in English | MEDLINE | ID: mdl-30674845

ABSTRACT

Hydrogels are an interesting class of materials used in extrusion-based 3D printing, e.g., for drug delivery or tissue engineering. However, new hydrogel formulations for 3D printing as well as a detailed understanding of crucial formulation properties for 3D printing are needed. In this contribution, hydrogels based on poly(ethylene glycol) diacrylate (PEG-DA) and the charged monomers 3-sulfopropyl acrylate and [2-(acryloyloxy)ethyl]trimethylammonium chloride are formulated for 3D printing, together with Poloxamer 407 (P407). Chemical curing of formulations with PEG-DA and up to 5% (w/w) of the charged monomers was possible without difficulty. Through careful examination of the rheological properties of the non-cured formulations, it was found that flow properties of formulations with a high P407 concentration of 22.5% (w/w) possessed yield stresses well above 100 Pa together with pronounced shear thinning behavior. Thus, those formulations could be processed by 3D printing, as demonstrated by the generation of pyramidal objects. Modelling of the flow profile during 3D printing suggests that a plug-like laminar flow is prevalent inside the printer capillary. Under such circumstances, fast recovery of a high vicosity after material deposition might not be necessary to guarantee shape fidelity because the majority of the 3D printed volume does not face any relevant shear stress during printing.

12.
Polymers (Basel) ; 8(6)2016 May 31.
Article in English | MEDLINE | ID: mdl-30979307

ABSTRACT

Composite reinforcing bars (rebars) that are used in concrete members with high performance (strength and durability) properties could have beneficial effects on the behavior of these members. This is especially vital when a building is constructed in an aggressive environment, for instance a corrosive environment. Although tension capacity/weight (or volume) ratios in composite rebars (carbon fiber reinforced polymer (CFRP), glass fiber reinforced polymer (GFRP), etc.) are very high when compared to steel rebars, major weaknesses in concrete members reinforced with these composite rebars may be the potential consequences of relatively poor bonding capacity. This may even be more crucial when the member is subjected to cyclic loading. Although monotonic bond tests are available in the literature, only limited experimental studies exist on bond characteristics under cyclic loading conditions. In order to fill this gap and propose preliminary design recommendations, 10 specimens of 10-mm-diameter ribbed CFRP rebars embedded in specially designed high strength concrete (f'c = 70 MPa) blocks were subjected to monotonic and cyclic pullout tests. The experimental results showed that cyclically loaded CFRP rebars had less bond strength than those companion specimens loaded monotonically.

13.
J AAPOS ; 19(3): 257-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26059673

ABSTRACT

PURPOSE: To evaluate the effectiveness of liquid crystal glasses (LCG) in the treatment of children with monocular amblyopia. METHODS: A total of 14 amblyopic eyes of 14 children with monocular amblyopia were enrolled in the study. LCG with appropriate refractive correction were ordered for each patient. Each patient was examined with the new LCG before treatment and monthly thereafter. The parents were informed about the use, care, and charging of the glasses. Best-corrected visual acuity was measured as Snellen decimal notation and converted to logarithm of the minimum angle of resolution (logMAR) for statistical analyses. RESULTS: The mean age of the study population was 7.4 ± 1.4 years. Ten patients (71%) had anisometropic amblyopia; 2 (14%), strabismic amblyopia; and 2 (14%), mixed amblyopia. The mean follow-up period was 4.0 ± 1.2 months (range, 3-7 months). The mean duration of using LCG was 8.2 ± 2.5 hours daily (range, 4-12 hours). All of 14 patients used the LCG as suggested. The mean logMAR best-corrected visual acuity of the amblyopic eyes was 0.6 ± 0.3 at baseline, improving to 0.3 ± 0.2 at final follow-up (P < 0.001). No side effects were observed. CONCLUSIONS: The current study demonstrated that LCG wear improved visual acuity in children with monocular amblyopia. Additional studies are needed to determine whether this effect is due to the LCG on/off feature or to refractive correction alone.


Subject(s)
Amblyopia/therapy , Eyeglasses , Liquid Crystals , Amblyopia/etiology , Amblyopia/physiopathology , Anisometropia/complications , Child , Child, Preschool , Female , Humans , Male , Strabismus/complications , Visual Acuity/physiology
14.
Int J Ophthalmol ; 7(1): 118-21, 2014.
Article in English | MEDLINE | ID: mdl-24634876

ABSTRACT

AIM: To investigate ophthalmologic findings in children with thalassemia major (TM) and compare the findings with healthy controls. METHODS: In a cross-sectional study, 43 children with thalassemia major from pediatric hematology outpatient clinics from two university hospitals and age/sex matched 47 healthy children were included in the study. After a complete ophthalmic examination, tear function tests including the Schirmer test, fluorescein tear break-up time (BUT), ultrasound pachymetry, and axial length measurement were performed. Obtained data was recorded for statistical analysis and the values of right eyes were compared between groups. RESULTS: The mean best corrected visual acuity was 1.34±0.75 in TM and 1.08±0.28 in controls. It was found lower than 0.1 logMAR unit in 10 (23.2%) children with TM and 2 (4.2%) in controls, and the difference was statistically significant (P<0.05). The mean central corneal thickness was 540±26.95 in children with TM and 536.98±20.45µm in controls (P>0.05). The mean axial length was 22.53±0.50 in TM and 22.57±0.43mm in the control group. The mean Schirmer test score was 19.94±6.91 in TM and 24.22±3.95mm in the control group (P<0.01). The mean BUT score was 9.62±1.28 in TM and 9.73±0.6s in the control group (P>0.05). CONCLUSION: In TM, while corneal thickness, axial length, and BUT are close to controls, the Schirmer scores are less than normal. The study revealed that TM may be affected by the tear function and visual acuity.

15.
Mol Vis ; 19: 1852-8, 2013.
Article in English | MEDLINE | ID: mdl-24019741

ABSTRACT

PURPOSE: Genetic factors are shown to have a role in the development of primary open angle glaucoma (POAG). The aim of this study was to determine the effects of genetic polymorphisms of transient receptor potential melastatin (TRPM) channel genes on the risk of POAG in a Turkish population. METHODS: Genomic DNA was extracted from the leukocytes of the peripheral blood, and 26 single nucleotide polymorphisms in the TRPM channel genes were analyzed in 179 patients with POAG and in 182 healthy controls of similar age by using the BioMark HD dynamic array system. RESULTS: There were marked changes in the genotype (TT, 26.8%; CT, 66.7%; CC, 6.5%) and allele (T, 60.1%; C, 39.9%) frequencies for the TRPM5 gene rs34551253 (Ala456Thr, in exon 9) polymorphism in patients when compared to the controls (TT, 11.3%; CT, 74.6%; CC, 14.1%, p = 0.0009; T, 48.6%; A, 51.4%, p = 0.0063). However, no associations with the other 25 polymorphisms studied were found. CONCLUSIONS: This is the first study to examine the involvement of TRPM channel gene variations in the risk of incident POAG. This study demonstrated that the TRPM5 gene rs34551253 (Ala456Thr) polymorphism may be associated with increased risk of developing POAG in the Turkish population.


Subject(s)
Genetic Association Studies , Genetic Predisposition to Disease , Glaucoma, Open-Angle/genetics , Polymorphism, Single Nucleotide/genetics , TRPM Cation Channels/genetics , Adult , Aged , Aged, 80 and over , Alleles , Case-Control Studies , Female , Gene Frequency/genetics , Humans , Male , Middle Aged
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