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Sheath blight caused by soil borne necrotrophic fungus Rhizoctonia solani [teleomorph-Thanatephorus cucumeris (Frank) Donk.] is a major disease of rice. The disease is increasing over the year in India and cause up to 69% yield loss under favourable conditions. A total of 67 accessions of Oryza nivara were screened to identify resistance against sheath blight during 2015. Out of these, 16 accessions were found moderately resistant (MR) which were further evaluated during the year 2016 and 2017. After three years of screening, 12 of them were found to have a consistent moderate resistant reaction whereas four of the O. nivara accessions namely, IRGC81941, IRGC102463C, CR100097 and CR100110A have shown moderately susceptible to susceptible reaction against sheath blight. A correlation study revealed that different disease variables measured were significantly (P < 0.05) correlated. All the genotypes and genotype × environment interaction had a significant (P < 0.001) effect on all the disease variables. Cluster analysis showed that all the accessions were clustered into four groups which showed resistant, MR, moderately susceptible and susceptible reactions. Among all the O. nivara accessions IRGC81941A showed the maximum potential against sheath blight due to a least relative lesion height of 22.80%. None of the accession had complete resistance to the disease. The identified promising accessions such as IRGC81835, IRGC81941A, CR100008 and CR100111B can be utilized in a sheath blight resistance breeding program.
Junglerice [Echinochloa colona (L.) Link] is a problematic weed in the northern grain region of Australia. Two pot experiments (Experiment 1 and Experiment 2) were conducted in a screen house to evaluate the growth and reproductive behavior of two biotypes (A, collected from a cotton (Gossypium hirsutum L.)–fallow; B, collected from a fence near a water channel) of E. colona in response to water stress (100%, 75%, 50%, and 25% water holding capacity [WHC]). Averaged across both biotypes, the plant height, biomass, and seed production of E. colona were reduced at 25% WHC compared with 100% WHC. However, E. colona still produced a considerable amount of seeds at 25% WHC (at least 365 seeds plant−1). Biotype A produced more seeds in the second experiment, while biotype B produced more seeds in the first experiment. In Experiment 2, at 100% WHC, biotype A produced more seeds (17,618 seeds plant−1) than biotype B (4,378 seeds plant−1), and similar observations were noticed for root biomass. Growth and seed production of E. colona at all moisture levels and environmental conditions ensure survival in an unpredictable environment and contribute to the weedy nature of this species. Results indicate that biotype A is more invasive than biotype B under favorable environmental conditions (100% WHC). This study suggests an enhanced competitive ability of some biotypes of E. colona in response to a range of environmental and soil moisture conditions in Australia. Under favorable environmental conditions, biotype A could be more problematic, as it has higher seed production than biotype B. Therefore, it is important to implement sustainable weed control methods for such biotypes in the early stages of crop growth to prevent loss of stored moisture.
Glyphosate-resistant junglerice [Echinochloa colona (L.) Link] is a problematic weed in mungbean [Vigna radiata (L.) R. Wilczek] crops in Australia. Due to limited herbicide options in mungbean, there is an increased interest in developing integrated management strategies for the sustainable control of E. colona. Pot experiments were conducted in a screenhouse in 2017 and 2018 by growing E. colona plants (glyphosate-resistant [GR] and glyphosate-susceptible [GS] biotypes) alone (1 plant pot−1) and in competition with 4 and 8 mungbean plants pot−1. Both biotypes were developed from a single population using the clone method. The growth and seed production of both GR and GS biotypes were similar in response to mungbean competition. Averaged over biotypes, there was a reduction in the growth and seed production of E. colona as crop plants increased. Compared with the weed plants grown alone, crop interference reduced E. colona height by 17% to 19%, tiller numbers by 69% to 82%, total shoot biomass by 85% to 91%, and inflorescence numbers by 74% to 91%. When E. colona was grown with 8 mungbean plants pot−1, leaf weight ratio increased by 42% compared with plants grown alone. Compared with weed plants grown alone, mungbean interference (4 and 8 plants pot−1) reduced weed seed production by 85% to 95%. These reductions were similar for both biotypes (GR and GS), suggesting that there was no fitness penalty associated with resistance. The results of this study suggest that mungbean interference can reduce E. colona growth and seed production, but it should not be considered as a stand-alone strategy to manage E. colona and similar species in mungbean. These results also highlight the need for integrating crop competition with other management strategies to achieve complete and sustainable management of this weed.
Stereotactic body radiotherapy (SBRT) is widely used for the treatment of stage-I non-small cell lung cancer (NSCLC). Patient-specific motion correlated with 4DCT could be essential for hypofractionated SBRT. All patients undergoing SBRT do not require motion management during the dose delivery. The objective of this study was to evaluate which patient may benefit from Gated SBRT.
Materials and methods
Treatment planning of 20 patients of stage-I NSCLC was analysed. Conventional and 4DCT scans were taken. Internal target volume as well as planning target volume (ITV and PTV) were determined in the CT data sets. PTVall phases created using 4DCT data sets and PTV15mm created using conventional CT data were compared. Also, ITVall phases were compared with ITV created from maximum intensity projections (ITVMIP). Suitability of patients for motion management-based treatment delivery was also evaluated.
The average ITVMIP to ITVall phases ratio is 1·06 indicating good agreement between them. Based on the ratio of intensity projections, 9 out of 17 patients were found suitable for our existing gated treatment.
4D CT is the main requirement in SBRT to identify the patients who can benefit from motion management during the dose delivery.
Perinatal exposure to sucrose or high-fructose corn syrup-55 (HFCS-55) in rats has previously been associated with altered hepatic fat content and composition post-weaning, although the effects on hepatic metabolism are unknown. The current study aimed to determine the sex-specific effects of maternal consumption of sucrose or HFCS-55 on the expression of hepatic lipogenic genes in the offspring. Liver samples were collected from offspring of albino Wistar rats provided with ad libitum access to either water (control), 10% sucrose or 10% HFCS-55 solution during pregnancy and lactation at 3 weeks (control n=16, sucrose n=22, HFCS-55 n=16) and 12 weeks (control n=16, sucrose n=10, HFCS-55 n=16) of age. Hepatic expression of the transcription factors such as carbohydrate response element-binding protein, sterol regulatory element-binding protein-1c and downstream genes was determined by quantitative real-time PCR. Sucrose-exposed offspring had higher hepatic SREBP-1c messenger RNA expression compared with control and HFCS-55 groups at both 3 weeks (P=0.01) and 12 weeks (P=0.03) of age. There were no differences in the expression of other hepatic lipogenic genes between groups at either 3 or 12 weeks. Thus, perinatal exposure to sucrose may be more detrimental to offspring hepatic metabolism compared with HFCS-55, independent of sex, and it will be important to evaluate the longer-term effects of perinatal sucrose exposure in future studies.
A nonparaxial investigation for propagation characteristics of q-Gaussian laser beam in rippled density plasma is studied by considering the relativistic nonlinearity. The field distribution in the medium is expressed in terms of q parameter and beam width parameter f. Nonlinear parabolic partial differential equation governing the evolution of complex envelope in slowly varying approximation is solved in a modulated density profile. Analytical theory of self-focusing including higher order terms in the expansion of dielectric function up to fourth order is developed and the variation of beam width parameter f with the distance of propagation for different parameters is studied. One may note that increased value of density ripple, laser intensity and depth of modulation, increases self-focusing whereas a lower value of q shows strong self-focusing. A comparative study between paraxial and nonparaxial study has also conducted. This study is useful for research in high energy density physics.
We have explored the thermodynamics of compressed magnetized plasmas in laboratory experiments and we call these studies ‘magnetothermodynamics’. The experiments are carried out in the Swarthmore Spheromak eXperiment device. In this device, a magnetized plasma source is located at one end and at the other end, a closed conducting can is installed. We generate parcels of magnetized plasma and observe their compression against the end wall of the conducting cylinder. The plasma parameters such as plasma density, temperature and magnetic field are measured during compression using HeNe laser interferometry, ion Doppler spectroscopy and a linear
probe array, respectively. To identify the instances of ion heating during compression, a PV diagram is constructed using measured density, temperature and a proxy for the volume of the magnetized plasma. Different equations of state are analysed to evaluate the adiabatic nature of the compressed plasma. A three-dimensional resistive magnetohydrodynamic code (NIMROD) is employed to simulate the twisted Taylor states and shows stagnation against the end wall of the closed conducting can. The simulation results are consistent to what we observe in our experiments.
Common cottonwood-based agroforestry system is widely adopted in Indian Indo-Gangetic plains. The stem cuttings of common cottonwood are raised in a nursery 10 to 12 months in rows spaced 0.5 mx0.5 m, before re-planting in the field. The longer duration of 10 to 12 months and wider spacing of stem cuttings in the nursery makes the entire transplants highly vulnerable to weed competition, especially during early establishment stages. The efficacy of preemergence herbicides and plastic and straw mulches for weed management in common cottonwood nursery was investigated at two sites in years 2014 and 2015. The major weed flora in the experimental field consisted of three grass weeds (crowfootgrass, feather lovegrass, and southern crabgrass), and four broadleaf weeds (scarlet pimpernel, garden spurge, niruri, and lesser swinecress). The integrated use of pendimethalin or alachlor applied PRE with paddy straw mulch significantly reduced density and biomass of both grass and broadleaf weeds compared to herbicide or straw mulch used alone, and provided similar level of weed control to hand weeding at both locations. Spreading of plastic mulch in the whole field after punching holes for common cottonwood stem cuttings, or in row spaces recorded similar weed control to hand-weeding. The integrated use of herbicides with straw mulch, and or plastic mulch alone significantly improved plant height, stem diameter, below- and above-ground biomass of common cottonwood plants compared to unweeded check. The study concluded that integrated use of herbicides plus paddy straw mulch or plastic mulch alone could be adopted for weed management in common cottonwood nursery plantations.
In this experiment, a comparative study of ion and X-ray emission from both a SiO2 aerogel foam and a quartz target is performed. The experiment is performed using Nd:glass laser system operated at laser energy up to 15 J with a pulse duration of 500 ps with focusable intensity of 1013–1014 W/cm2 on target. X-ray fluxes in different spectral ranges (soft and hard) are measured by using X-ray diodes covered with Al filters of thickness 5 µm (0.9–1.56 keV) and 20 µm (3.4–16 keV). A 2.5 times enhancement in soft X-ray flux (0.9–1.56 keV) and a decrease of 1.8 times in hard X rays (3.4–16 keV) for 50 mg/cc SiO2 aerogel foam is observed compared with the solid quartz. A decrease in the flux of the K-shell line emission spectrum of soft X rays is noticed in the case of the foam targets. The high-resolution K-shell spectra (He-like) of Si ions in both the cases are analyzed for the determination of plasma parameters by comparing with FLYCHK simulations. The estimated plasma temperature and density are Tc = 180 eV, ne = 7 × 1020 cm−3 and Tc = 190 eV, ne = 4 × 1020 cm−3 for quartz and SiO2 aerogel foam, respectively. To measure the evolution of the plasma moving away from the targets, four identical ion collectors are placed at different angles (22.5, 30, 45, and 67.5°) from target normal. The angular distribution of the thermal ions are scaled as cosnθ with respect to target normal, where n = 3.8 and 4.8 for the foam and quartz, respectively. The experimental plasma volume measured from the ion collectors and shadowgraphy images are verified by a two-dimensional Eulerian radiative–hydrodynamic simulation (POLLUX code).
Bovine calf scours reported to be caused by multiple aetiologies resulting in heavy mortality in unweaned calves and huge economic loss to the dairy farmers. Among these, cryptosporidiosis is an emerging waterborne zoonoses and one of the important causes of neonatal calf diarrhoea. Poor immune response coupled with primary cryptosporidial infections predispose neonatal calves to multiple secondary infections resulting in their deaths. In the present study, faecal samples from 100 diarrhoeic calves randomly picked up out of 17 outbreaks of bovine calf diarrhoea in periurban Ludhiana, Punjab in Northern India were subjected to conventional (microscopy, modified Zeihl–Neelsen (mZN) staining) and immunological and molecular techniques (faecal antigen capture ELISA and PCR) for detection of primary Cryptosporidium parvum infection as well as other frequently reported concurrent pathogens, viz. rotavirus and coronavirus, Salmonella spp., Escherichia coli, Clostridium perfringens and Eimeria spp. The faecal antigen capture ELISA and PCR revealed 35% prevalence of C. parvum in contrast to 25% by mZN staining with a relatively higher prevalence (66·7%) in younger (8–14-day-old) calves. The detection rate of the other enteropathogens associated with C. parvum was 45·71% for C. perfringens followed by Salmonella spp (40·0%), rotavirus (36·0%), coronavirus (16·0%), E. coli (12·0%) and Eimeria spp (4·0%) The sensitivity for detection of C. parvum by ELISA and mZN staining in comparison to PCR was 97·14% and 72·72%, respectively. An important finding of the study was that C. parvum alone was found in only 10% of the diarrhoeic faecal samples, whereas, majority of the samples (90%) showed mixed infections ranging from a combination of two to five agents. This is the first documentary proof of C. parvum and associated pathogens responsible for severe periurban outbreaks of bovine calf diarrhoea culminating in heavy mortality from Northern India.
The interaction of laser radiation with low density aerogels is of crucial importance in areas such as the creation of coherent radiation sources in the X-ray range, simulation of astrophysical as well as nuclear fusion phenomena in laboratory and fundamental studies of the properties of soft condensed matter under dynamic pressure in the Mbar range. In the present paper, the experimental results on the X-ray emission of laser induced plasma in TEOS based, MTMS based aerogels and solid quartz targets, are reported. The aerogels were produced by the sol-gel processing of tetraethoxysilane (TEOS) and methyltrimethoxysilane (MTMS) followed by supercritical drying. Silica alcogels were produced using 0.001 M oxalic acid (C2H4O4), 0.5 M ammonium hydroxide (NH4OH) catalysts. Different densities of aerogels varying from 0.02 to 0.06 g/cm3 have been obtained using different molar ratios of TEOS, MTMS, ethanol and catalysts. The laser, with intensity up to 2 x 1014 W/m2, interaction with TEOS and MTMS based aerogels have been conducted using 30J/500 ps Nd : glass laser system. The resulting soft (0.8 – 1.56 Kev) and hard (>4 Kev) X-ray emissions have been measured using semiconductor photodiodes. It has been observed that the soft X-ray yield increases by a factor of two for the silica aerogel targets compared to the X-ray emission from the solid quartz target, whereas the hard X-ray yield reduces. The enhanced soft X-ray yield in silica aerogel targets is attributed to the large volume heating.
A s-polarized short-pulse laser impinged obliquely on an overdense plasma slab is shown to produce very significant second harmonic in the direction of specular reflection and transmission. The laser induces a non-linear current on electrons, which is curl free. However, with sharp plasma boundary, it gives rise to electromagnetic radiation at the second harmonic. Our formalism includes multiple reflections of the incident and second-harmonic waves from both the front and rear surfaces. The present work includes finiteness of the slab. The normalized second-harmonic amplitude acquires a sharp peak at some specific angle of incidence for a particular set of parameters dependent on thickness of the slab and plasma density.
In the present research work, the authors have investigated the self-focusing and defocusing of Hermite-cosh-Gaussian laser (HChG) beam in an inhomogeneous rippled density plasmas. By taking the relativistic non-linearity into account, an equation for envelope is set up and solved using Wentzel–Kramers–Brillouin and the paraxial ray approximation. An ordinary non-linear differential equation governing the beam width parameter as a function of propagation distance is set up for different mode structures of the beam. Further, a numerical study of this differential equation is carried for suitable set of plasma and laser parameters. The beam undergoes periodic self-focusing/defocusing due to relativistic non-linearity. We also report the comparison between self-focusing/defocusing of HChG beam in the absence and presence of density ripple. Presence of ripple does not only leads to substantial increase in self-focusing length, but also results in oscillatory character with decreasing f. In a relativistic case, strong oscillatory self-focusing and defocusing is observed. Further, self-focusing is enhanced with increased value of decentered parameter.
Intrauterine growth restriction (IUGR) has adverse effects on metabolic health and early life, whereas physical activity is protective against later development of metabolic disease. Relationships between birth weight and physical activity in humans, and effects of IUGR on voluntary activity in rodents, are mixed and few studies have measured physical activity in a free-ranging environment. We hypothesized that induced restriction of placental growth and function (PR) in sheep would decrease spontaneous ambulatory activity (SAA) in free-ranging adolescent and young adult progeny from multi-fetal pregnancies. To test this hypothesis, we used Global Positioning System watches to continuously record SAA between 1800 and 1200 h the following day, twice during a 16-day recording period, in progeny of control (CON, n=5 males, 9 females) and PR pregnancies (n=9 males, 10 females) as adolescents (30 weeks) and as young adults (43 weeks). PR reduced size at birth overall, but not in survivors included in SAA studies. In adolescents, SAA did not differ between treatments and females were more active than males overall and during the day (each P<0.001). In adults, daytime SAA was greater in PR than CON females (P=0.020), with a similar trend in males (P=0.053) and was greater in females than males (P=0.016). Adult SAA was negatively correlated with birth weight in females only. Contrary to our hypothesis, restricted placental function and small size at birth did not reduce progeny SAA. The mechanisms for increased daytime SAA in adult female PR and low birth weight sheep require further investigation.
Presbyopia is a ubiquitous age-related disability of the eye, affecting an estimated 1.04 billion people worldwide, reducing their ability to focus on nearby objects. The various solutions to this inevitable vision deterioration are not compromise-free, with a growing need for approaches beyond conventional spectacles. The research motivation for this work is the unique solution offered by liquid crystal (LC) contact lenses to create compromise-free vision across the whole field of view. The distinctive property of LC lenses is that they are switchable, with the application of a voltage activating the lens. The change in focal power is facilitated via a voltage-dependent change in refractive index of the LC. We have successfully demonstrated several versions of electrically switchable LC contact lenses with variable additional optical power of up to +3.00 D, ideal for the correction of presbyopia.
This paper offers a review of the optical and electro-optical performance recently demonstrated for the different modes of operation realized in nematic systems, including planar (homogeneous) and vertically aligned (homeotropic) aligned devices. The change in optical power obtained depends on the choice of geometry and LC material. A material with higher birefringence allows a thinner LC-lens layer to achieve a particular focal power. In the homeotropic geometry, the refractive index of the LC layer is a minimum in the ‘off’ state (ordinary refractive index, no) and the mode is polarization-independent, offering a significant advantage over planar lens designs. The construction is also simplified as only one alignment layer needs to be rubbed. Depending on the geometry used, continuously variable changes in focal power of up to +3.00D have been achieved. The response time of the lenses can be better than half a second, achieved with small applied voltages of ~7Vrms.
A further important stage in the optimization of the contact lenses is the inclusion of graphene as the electrodes. Conventional ITO electrodes are too brittle for these flexible optical systems. The paper also reviews the successful incorporation of graphene into the lenses, with excellent optical and electro-optical results. The device demonstrates the huge potential of graphene in an unconventional liquid crystal device geometry that includes curvature over a relatively large area.
Rigid ryegrass, an important annual weed species in cropping regions of
southern Australia, has evolved resistance to 11 major groups of herbicides.
Dose–response studies were conducted to determine response of three
clethodim-resistant populations and one clethodim-susceptible population of
rigid ryegrass to three different frost treatments (−2 C).
Clethodim-resistant and -susceptible plants were exposed to frost in a frost
chamber from 4:00 P.M. to 8:00 A.M. for three nights before or after
clethodim application and were compared with plants not exposed to frost. A
reduction in the level of clethodim efficacy was observed in resistant
populations when plants were exposed to frost for three nights before or
after clethodim application. In the highly resistant populations, the
survival percentage and LD50 were higher when plants were exposed
to frost before clethodim application compared with frost after clethodim
application. However, frost treatment did not influence clethodim efficacy
of the susceptible population. Sequencing of the acetyl coenzyme A
carboxylase (ACCase) gene of the three resistant populations identified
three known mutations at positions 1781, 2041, and 2078. However, most
individuals in the highly resistant populations did not contain any known
mutation in ACCase, suggesting the resistance mechanism was a nontarget
site. The effect of frost on clethodim efficacy in resistant plants may be
an outcome of the interaction between frost and the clethodim resistance
Rigid ryegrass is the most-troublesome, herbicide-resistant weed in cropping systems of southern Australia. Field experiments were undertaken at Roseworthy, South Australia, in 2013 and 2014, to identify effective herbicide options for the control of clethodim-resistant rigid ryegrass in Clearfield canola. PPI trifluralin + triallate followed by (fb) POST imazamox + imazapyr + clethodim + butroxydim had the lowest plant density of rigid ryegrass in 2014 and provided superior control compared with the standard grower practice of PPI trifluralin + triallate fb POST imazamox + imazapyr + clethodim in 1 of 2 yr. Propyzamide either alone or as a split application (PPI fb POST) or in combination with clethodim provided similar rigid ryegrass control to that of the standard grower practice (38 to 553 plants m−2). Rigid ryegrass treated with PPI dimethenamid-P, pethoxamid, pethoxamid + triallate, and PPI trifluralin fb carbetamide POST produced significantly more seeds than the standard grower practice, which would lead to reinfestation of subsequent crops. Canola yield responded positively to effective herbicide treatments, especially in 2014, when rigid ryegrass density was greater. PPI dimethenamid-P and pethoxamid alone or in combination with triallate and propyzamide were ineffective in reducing rigid ryegrass density and seed production to levels acceptable for continuous cropping systems.
Bacterial blight (BB) of rice caused by Xanthomonas oryzae pv. oryzae (Xoo) is a major biotic constraint of rice production in all the major irrigated/lowland rice growing regions of Asia, including Punjab and its adjoining states in India. None of the individual BB resistant Xa/xa genes is effective against Punjab pathotypes. In the present study, we have screened 1176 accessions, comprising 1007 accessions of A genome species Oryza glaberrima, O. barthii, O. nivara, O. rufipogon, O. longistaminata, O. meridionalis, O. glumaepatula and 169 accessions from ten other wild species having CC, FF, EE, BBCC and CCDD genomes against two most recently evolved Xoo pathotypes viz. PbXo-10 and PbXo-8 in Punjab state of India, for two constitutive years 2014 and 2015. Based on 2 years of data, four accessions of O. glaberrima (IRGC102206, IRGC1022445, IRGC102512 and IRGC102520) and two of the O. longistaminata accessions (IRGC92624 and IRGC101754) were identified with immune reaction against PbXo-8. For PbXo-10, O. longistaminata showed large number of accessions with complete to partial resistance followed by O. rufipogon (8), O. nivara (2), O. punctata (2) and O. officinalis (1). Two of the O. longistaminata accessions IRGC92624 and IRGC92644 from Mali were found to have resistance against both the Xoo pathotypes indicating presence of BB resistance gene other than Xa21. These can be transferred to elite cultivars of O. sativa for better management of BB.
Addition of antibiotics to artificial diets of insects is a key component in the rearing of insects in the laboratory. In the present study an antimicrobial agent, streptomycin sulphate was tested for its influence on survival and fitness of Spodoptera litura (Fabricus) (Lepidoptera: Noctuidae) as well as its gut microbial diversity. The antibiotic did not adversely affect the survival of S. litura. Faster growth of larvae was recorded on diet amended with different concentrations of streptomycin sulphate (0.03, 0.07 and 0.15%) as compared to diet without streptomycin sulphate. The overall activity of various digestives enzymes increased on S+ diet while the activity of detoxifying enzymes significantly decreased. In addition, alteration in microbial diversity was found in the gut of S. litura larvae fed on diet supplemented with antibiotic (S+) and without antibiotic (S−).