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Inbred cultivars and advanced breeding lines have been subjected to numerous recombination cycles, have strong allelic selection for desired traits, and share important attributes for adaptation and agronomic performance. Genetic variation in elite gene pools captured using molecular markers is immediately useful for cultivar development. The primary goal of this study was to implement a genome‐wide association study for 17 agronomic traits using elite inbred lines. A panel consisting of 237 elite hard red spring wheat (Triticum aestivum L.) lines from different wheat breeding institutions in North America were evaluated in 11 locations over 2 yr. A total of 19,192 polymorphic single‐nucleotide polymorphism (SNP) markers from the Illumina 90K SNP array and markers linked to major genes controlling plant height, photoperiod sensitivity, and vernalization were used to assay the population. Linkage disequilibrium was observed to decay within a map distance of ∼3 cM in the A and B genomes and 7 cM in the D genome. A total of 226 marker‐trait associations were identified. Potentially novel associations were detected for grain yield on chromosome 2B and kernels per spike on 1B and 7D, whereas others colocalized with well‐known adaptation loci for photoperiod response, vernalization, and plant height. The frequency of positive alleles for specific marker‐trait associations differed among the programs, suggesting targets for introgression by the respective breeding programs.

Nanofluids are well known for their enhanced thermal properties. In spite of their excellent properties, there are certain hindrances to their applications on large scale. The issue of nanoparticle agglomeration in the base fluid with the consequent stability related issues is one of the main obstacles to the usage of nanofluids. Stability is crucial because the longer the nanofluids remain stable, the better their capacity to retain their thermal properties. Hence there is a need to evolve long-term stable nanofluids. Since there are a lot of factors, which are affecting the stability of the nanofluids, there is a need to optimize the process parameters. In this regard, central composite rotatable design (CCRD) was applied in this study to optimize the independent parameters of stability of ferric oxide nanofluids. For this, the performance of nanofluids was assessed by measuring the nephelometric turbidity units (NTU), based on the independent variables such as percentage of intensity of the nanoparticle, pH of the base fluid, and percentage volume concentration of the surfactant. All the parameters that are affecting individually and mutually were validated statistically using analysis of variance (ANOVA). A regression equation to evaluate the NTU was developed. The obtained results showed that the values predicted by the model and that obtained from the experiments were in good agreement with each other. It is observed that more than 99.65% of the variation could be predicted by the model developed for NTU. The response surface methodology (RSM) has revealed that the ideal process parameters for greater stability of nanofluids are 0.01% particle volume intensity, pH 3.2, and 0.6% surfactant intensity. [ABSTRACT FROM AUTHOR]

Grain sorghum is a versatile crop, which can thrive under limited water and other inputs. However, crop loss from weed infestation continues to be a major constraint in grain sorghum production. Particularly, post‐emergence grass weed control is a great challenge in grain sorghum due to the lack of herbicide options. Unlike in other major crops, such as maize or soybean, herbicide‐resistant sorghum technology that can facilitate weed control throughout crop growing season is not available to growers yet. The development of herbicide‐resistant sorghum can have potential to improve weed management, including post‐emergence grass weed control. One of the major concerns in the development of such technology in sorghum is escape of resistance traits into weedy relatives of sorghum (e.g. shattercane and johnsongrass). This review focuses on sources of herbicide resistance in sorghum, the status of the development of herbicide‐resistant sorghum technologies, overview of breeding methods, and limitations in the development of such sorghum technology as well as economic benefits for sorghum growers. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Refractive index studies are carried out on two highly polar liquid crystals: 1.N-(p-n-methoxy benzylidene)-p-amino benzonitrile, PmBAB, 2.N-(p-n-ethoxy benzylidene)-p-amino benzonitrile, PeBAB. The experimental investigations are carried out in the visible region at four different wavelengths, namely, 633, 589, 546 and 436 nm. The two compounds exhibit only the nematic liquid crystalline phase in between the isotropic and crystalline solid. The dispersive powerωis estimated for two consecutive wavelengths for the case of ,neandnofor different wavelengths and found to be constant with temperature. Further the temperature gradients ofneandnoare estimated, and the crossover temperature is obtained using dno/dTfor all the wavelengths. [ABSTRACT FROM PUBLISHER]

Purpose: To determine whether MRI in combination with an intravascular contrast agent is sensitive to pharmacologically induced vasodilation and vasoconstriction in the rat kidney.Materials and Methods: R(2) imaging was performed in 25 Sprague Dawley rats at 3 Tesla in the presence of ferumoxytol, an ultrasmall superparamagnetic iron oxide (USPIO) agent with a long plasma half-life. R(2) changes were measured following manipulation of blood volume by intravenous administration of adenosine, a short-acting vasodilator, or N(G)-nitro-L-arginine methyl ester (L-NAME), a long-acting nitric oxide synthase inhibitor with known vasoconstrictive effects. As a control, R(2) responses to adenosine and L-NAME were also examined in the absence of ferumoxytol.Results: In the presence of ferumoxytol, adenosine induced a significant increase in R(2), while L-NAME produced a reduction, although the latter was not statistically significant. Control experiments revealed small R(2) changes in the absence of ferumoxytol. An incidental finding was that the cross-sectional area of the kidney also varied dynamically with adenosine and L-NAME.Conclusion: Our results suggest that ferumoxytol-enhanced R(2) imaging is sensitive to adenosine-induced vasodilation. The responses to L-NAME, however, were not statistically significant. The variations in kidney size and the R(2) changes in the absence of ferumoxytol may reflect alterations in the volume of the renal tubules. [ABSTRACT FROM AUTHOR]

Objective: Cartilage morphology displays sensitivity to change in osteoarthritis (OA) with quantitative MRI (qMRI). However, (sub)regional cartilage thickness change at 3.0 Tesla (T) has not been directly compared with radiographic progression of joint space narrowing in OA participants and non-arthritic controls.Methods: A total of 145 women were imaged at 7 clinical centres: 86 were non-obese and asymptomatic without radiographic OA and 55 were obese with symptomatic and radiographic OA (27 Kellgren-Lawrence grade (KLG)2 and 28 KLG3). Lyon-Schuss (LS) and fixed flexion (FF) radiographs were obtained at baseline, 12 and 24 months, and coronal spoiled gradient echo MRI sequences at 3.0 T at baseline, 6, 12 and 24 months. (Sub)regional, femorotibial cartilage thickness and minimum joint space width (mJSW) in the medial femorotibial compartment were measured and the standardised response means (SRMs) determined.Results: At 6 months, qMRI demonstrated a -3.7% "annualised" change in cartilage thickness (SRM -0.33) in the central medial femorotibial compartment (cMFTC) of KLG3 subjects, but no change in KLG2 subjects. The SRM for mJSW in 12-month LS/FF radiographs of KLG3 participants was -0.68/-0.13 and at 24 months was -0.62/-0.20. The SRM for cMFTC changes measured with qMRI was -0.32 (12 months; -2.0%) and -0.48 (24 months; -2.2%), respectively.Conclusions: qMRI and LS radiography detected significant change in KLG3 participants at high risk of progression, but not in KLG2 participants, and only small changes in controls. At 12 and 24 months, LS displayed greater, and FF less, sensitivity to change in KLG3 participants than qMRI. [ABSTRACT FROM AUTHOR]

Objective: To identify subregional differences in femorotibial cartilage morphology between healthy controls and women with different grades of radiographic knee osteoarthritis (OA).Design: 158 women aged > or =40 years were studied. Weight-bearing extended anterior-posterior (AP) and Lyon schuss radiographs were obtained and the Kellgren Lawrence grade (KLG) determined. 97 women had a body mass index (BMI)< or =28, no symptoms, and were AP KLG0. 61 women had a BMI> or =30, symptoms in the target knee, and mild (KLG2=31) to moderate (KLG3=30) medial femorotibial radiographic OA in the AP views. Coronal spoiled gradient echo water excitation sequences were acquired at 3.0 Tesla. Total plate and regional measures of cartilage morphology of the weight-bearing femorotibial joint were quantified.Results: KLG2 participants displayed, on average, thicker cartilage than healthy controls in the medial femorotibial compartment (particularly anterior subregion of the medial tibia (MT) and peripheral [external, internal] subregions of the medial femur), and in the lateral femur. KLG3 participants displayed significantly thinner cartilage than KLG0 participants in the medial weight-bearing femur (central subregion), in the external subregion of the MT, and in the internal subregion of the lateral tibia. These differences were generally unaffected when possible effects of demographic covariates were considered.Conclusions: The results indicate that in femorotibial OA regional cartilage thickening and thinning may occur, dependent on the (radiographic) disease status of the joint. These changes appear to display a heterogeneous spatial pattern, where certain subregions are more strongly affected than others. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Cerebral palsy (CP) is caused by either hypoxia-ischemia (H-I) or long-standing causative factors such as inflammation or genetics. Multiple pathophysiological events over time are thought to contribute eventually to cerebral palsy. Our objective was to examine whether the immediate response of the fetus to an acute H-I event determined the motor deficits associated with cerebral palsy. METHODS: Serial diffusion-weighted imaging were performed on 79% gestation New Zealand white rabbits using a 3-Tesla magnetic resonance scanner during 40 minutes of uterine ischemia, 20 minutes of reperfusion, and at 4, 24, and 72 hours. Individual fetuses were tracked to near term, and the delivered kits were divided into hypertonic H-I (n = 18), nonhypertonic H-I (n = 9), stillbirth H-I (n = 4), and control groups (n = 16). RESULTS: The hypertonia group had significantly less of a nadir in apparent diffusion coefficient (ADC) during H-I (71.6 +/- 23.8% vs 84.5 +/- 9.3% baseline) and slower and incomplete recovery of ADC during reperfusion compared with the nonhypertonic group. All fetuses in the hypertonic and stillbirth groups had an ADC nadir of less than 0.83mum(2)/msec (70.3% decrease from baseline), whereas 94% of control animals had an ADC nadir greater than this value. The difference between outcome groups was the largest at 4 hours reperfusion and persisted for 24 hours. INTERPRETATION: Serial fetal brain scans indicate that the immediate response of a fetus to H-I is crucial to the development of hypertonia. If the fetal brain can be scanned at the time of insult, ADC changes can predict which fetuses will have an unfavorable outcome. Ann Neurol 2007;61:307-314. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) is used to examine the distribution of glycosaminoglycan in cartilage. This study sought to characterize dGEMRIC in the evaluation of knee osteoarthritis (OA) according to various radiographically determined disease parameters, and to examine the relationship between alignment of the knee joint and the lateral:medial dGEMRIC ratio. METHODS: Thirty-one patients with knee OA underwent MRI with a dGEMRIC protocol at 1.5T. Semiflexed knee radiographs and full-limb radiographs were also obtained for assessment of alignment. RESULTS: Compartments of the knee joint without joint space narrowing had a higher dGEMRIC index than those with any level of narrowing (mean 408 msec versus 365 msec; P = 0.001). In knees with 1 unnarrowed (spared) and 1 narrowed (diseased) compartment, the dGEMRIC index was greater in the spared versus the diseased compartment (mean 395 msec versus 369 msec; P = 0.001). In spared compartments, there was a trend toward a lower dGEMRIC index with increasing Kellgren/Lawrence (K/L) radiographic severity grade; the spared compartments of knees with a K/L grade 2 had a higher dGEMRIC index than those of knees with a K/L grade 4 (mean 425 msec versus 371 msec; P < 0.05). There was a range of dGEMRIC values in the spared compartments within a given K/L grade, demonstrating biochemical differentiation of disease in radiographically comparable compartments. Almost all compartments with narrowing had dGEMRIC indices of <400 msec. Valgus-aligned knees tended to have lower dGEMRIC values laterally, and varus-aligned knees tended to have lower dGEMRIC values medially; as a continuous variable, alignment correlated with the lateral:medial dGEMRIC ratio (Pearson's R = 0.43, P = 0.02). CONCLUSION: The biochemical information provided by dGEMRIC scans may augment radiography by improving the differentiation of disease status within a given radiographic grade, especially in early OA. [ABSTRACT FROM AUTHOR]

We report a 3-year-old girl born with fair complexion which became darker. The color change was insidious in onset at the age of 5 months, asymptomatic and progressive involving the entire body surface. Histopathology revealed increased pigmentation of the epidermal basal layer. Universal acquired melanosis is a rare form of hypermelanosis which was synonymously referred to as "Carbon baby". This is a rare presentation with only one earlier case report. [ABSTRACT FROM AUTHOR]

Leprosy remains an important problem globally. Timely detection of new cases and prompt treatment with MDT continue to be the main intervention strategies. We review the various issues related to classification, treatment, drug resistance and the possible steps to eliminate the disease in the near future. The need for newer anti leprosy agents has been felt and various agents like fluroquinolones, macrolides and minocycline have all been tried in various combinations and duration. Uniform MDT in all leprosy patients might be a logical one too. Drug resistance can be identified by PCR based DNA sequence analysis which saves much time. Drugs like thalidomide analogues, pentoxifylline, selective cytokine inhibitory drugs have proved effective in controlling type-2 reaction in leprosy patients. New drugs for leprosy reactions are still needed. Far from being eliminated as a public health problem, leprosy still causes a considerable long term morbidity in both developing and developed world. New treatment and the optimal length of MDT requires further research. We need genome based technology to address the unresolved issues of transmission of M. leprae.