The limit to wheat water-use efficiency in eastern Australia. I. Gradients in the radiation environment and atmospheric demand

In the wheatbelt of eastern Australia, rainfall shifts from winter dominated in the south (South Australia, Victoria) to summer dominated in the north (northern New South Wales, southern Queensland). The seasonality of rainfall, together with frost risk, drives the choice of cultivar and sowing date, resulting in a flowering time between October in the south and August in the north. In eastern Australia, crops are therefore exposed to contrasting climatic conditions during the critical period around flowering, which may affect yield potential, and the efficiency in the use of water (WUE) and radiation (RUE). In this work we analysed empirical and simulated data, to identify key climatic drivers of potential water- and radiation-use efficiency, derive a simple climatic index of environmental potentiality, and provide an example of how a simple climatic index could be used to quantify the spatial and temporal variability in resource-use efficiency and potential yield in eastern Australia. Around anthesis, from Horsham to Emerald, median vapour pressure deficit (VPD) increased from 0.92 to 1.28 kPa, average temperature increased from 12.9 to 15.2°C, and the fraction of diffuse radiation (FDR) decreased from 0.61 to 0.41. These spatial gradients in climatic drivers accounted for significant gradients in modelled efficiencies: median transpiration WUE (WUEB/T) increased southwards at a rate of 2.6% per degree latitude and median RUE increased southwards at a rate of 1.1% per degree latitude. Modelled and empirical data confirmed previously established relationships between WUEB/T and VPD, and between RUE and photosynthetically active radiation (PAR) and FDR. Our analysis also revealed a non-causal inverse relationship between VPD and radiation-use efficiency, and a previously unnoticed causal positive relationship between FDR and water-use efficiency. Grain yield (range 1-7 t/ha) measured in field experiments across South Australia, New South Wales, and Queensland (n = 55) was unrelated to the photothermal quotient (Pq = PAR/T) around anthesis, but was significantly associated (r2 = 0.41, P < 0.0001) with newly developed climatic index: a normalised photothermal quotient (NPq = Pq . FDR/VPD). This highlights the importance of diffuse radiation and vapour pressure deficit as sources of variation in yield in eastern Australia. Specific experiments designed to uncouple VPD and FDR and more mechanistic crop models might be required to further disentangle the relationships between efficiencies and climate drivers.

The effect of radiation on the electron pairing in a multiband system

The possible occurrence of a generalized (1-wave) nonequilibrium superconducting state in a multiband system under certain conditions is studied. In the model the radiation field causes interband mixing, and phonons of an appropriate mode (branch) are involved in the interband scattering of electrons of two conduction bands of the system. The strength of the generalized 1-wave pairing interaction between quasiparticles belonging to new radiation admixed states depends on the density (n o/V) of quanta in the system. The coupling constant has the form Xl= AiB(n o/V)/[C + B(no/V)], where A1, B, and C are parameters. For C > B(n0/V), the transition temperature T1* increases with (no/V) in the initial stages. It levels off with higher power. With further increase of power, the transition temperature is expected to drop sharply due to heating effects which cause pair breaking. Estimates show that p-wave (triplet state) pairing may be possible under radiation-induced nonequilibrium situations in appropriate systems. Estimates for lifetimes of various processes quasiparticle, phonon, pair relaxation, and photon-induced mixing) show that the coherence required for the mixing and pairing effects will be maintained for the temperature range and photon density considered.

Emotional intelligence development in student radiation therapists: A longitudinal pilot study

Emotional intelligence (EI) is defined as “the ability to recognise, understand and manage emotions in ourselves and others” [1]. Initially identified as a concept applied to leadership and management, EI is now recognised as an important skill in a number of areas, including healthcare [2]. Empathy (the ability to see the world through someone else’s eyes) is known to play an important role in the therapeutic relationship with patients [3]. As EI has been shown to improve empathy [4], it is clear that developing the EI of student health professionals should benefit patients in the long term. It is not surprising, then, that a number of studies have investigated the role of EI in medical, dental and nursing students, however there is little reported evidence relating to EI development in pre-registration radiation therapy (RT) students.

Emotional intelligence development in radiation therapy students: A longitudinal study

Purpose: Emotional intelligence (EI) is an increasingly important aspect of a health professional’s skill set. It is strongly associated with empathy, reflection and resilience; all key aspects of radiotherapy practice. Previous work in other disciplines has formed contradictory conclusions concerning development of EI over time. This study aimed to determine the extent to which EI can develop during a radiotherapy undergraduate course and identify factors affecting this. Methods and materials: This study used anonymous coded Likert-style surveys to gather longitudinal data from radiotherapy students relating to a range of self-perceived EI traits during their 3-year degree. Data were gathered at various points throughout the course from the whole cohort. Results: A total of 26 students provided data with 14 completing the full series of datasets. There was a 17·2% increase in self-reported EI score with a p-value<0·0001. Social awareness and relationship skills exhibited the greatest increase in scores compared with self-awareness. Variance of scores decreased over time; there was a reduced change in EI for mature students who tended to have higher initial scores. EI increase was most evident immediately after clinical placements. Conclusions: Radiotherapy students increase their EI scores during a 3-year course. Students reported higher levels of EI immediately after their clinical placement; radiotherapy curricula should seek to maximise on these learning opportunities.

Quality of life changes during conformal radiation therapy for prostate carcinoma

BACKGROUND: The objective of this study was to describe prospectively quality of life (QOL) before and after radiotherapy for patients with prostate carcinoma. METHODS: Forty-three patients with T1-T3 prostate carcinoma who underwent conformal external beam radiation therapy were randomized either to the complete European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaire (EORTC QLQ-C30) or the Medical Outcomes Study Group Short Form Health Survey (SF-36) at baseline, at 3 weeks and 6 weeks after initial treatment, and at 6 weeks and 5 months after the completion of radiotherapy. The measures were self-reported patient QOL, and values are given as the mean +/- standard error of the mean. Changes in QOL are described from baseline to the end of treatment in both questionnaire groups. RESULTS: Emotional role functioning, as measured with the SF-36 questionnaire, significantly improved from 68.2 +/- 9.9 at baseline to 93.3 +/- 5.2 at the end of therapy (P = 0.02). The EORTC QLQ-C30 questionnaire revealed consistent values of emotional functioning during treatment (72.7 +/- 5.9 at baseline) but showed a significant improvement 6 weeks after therapy (89.0 +/- 4.4; P = 0.01). Role functioning deteriorated from 80.1 +/- 6.5 at baseline to 62.5 +/- 8.8 at the end of radiotherapy (P = 0.02). Symptoms of fatigue were shown to increase significantly from 26.9 +/- 6.0 at baseline to 37.7 +/- 7.6 at the end of therapy (P = 0.02). No significant changes in the other dimensions were observed in either questionnaire. CONCLUSIONS: After radiotherapy for prostate carcinoma, patients experience a temporary deterioration of fatigue and role functioning, as measured with the EORTC QLQ-C-30. Despite physical deterioration, the authors observed an improvement in emotional functioning scores with both questionnaires. This may have been due to psychological adaptation and coping.

Circular dichroism and nuclear magnetic resonance studies on the complexation of valinomycin with calcium

Complexation of valinomycin (VM) with the divalent cation Ca2+ in a lipophilic solvent, acetonitrile (CH3-CN), has been studied by using circular dichroism and proton and carbon- 13 nuclear magnetic resonance (‘H NMR and I3C NMR). From analyses of the spectral data, it is concluded that VM forms a 2:l (peptideion-peptide) sandwich complex with Ca2+, at low concentration of VM. At moderate conocentrations of the salt, in addition to the sandwich complex, an equimolar (1:l) complex different from those observed for potassium and sodium is also observed. At very large concentrations of the calcium salt, the data suggested a complex with a conformation similar to that of the free VM in polar solvents. Possible conformations for the sandwich and the equimolar VM-calcium complexes are proposed.

Net radiation dynamics: performance of 20 daily net radiation models as related to model structure and intricacy in two climates.

We compared daily net radiation (Rn) estimates from 19 methods with the ASCE-EWRI Rn estimates in two climates: Clay Center, Nebraska (sub-humid) and Davis, California (semi-arid) for the calendar year. The performances of all 20 methods, including the ASCE-EWRI Rn method, were then evaluated against Rn data measured over a non-stressed maize canopy during two growing seasons in 2005 and 2006 at Clay Center. Methods differ in terms of inputs, structure, and equation intricacy. Most methods differ in estimating the cloudiness factor, emissivity (e), and calculating net longwave radiation (Rnl). All methods use albedo (a) of 0.23 for a reference grass/alfalfa surface. When comparing the performance of all 20 Rn methods with measured Rn, we hypothesized that the a values for grass/alfalfa and non-stressed maize canopy were similar enough to only cause minor differences in Rn and grass- and alfalfa-reference evapotranspiration (ETo and ETr) estimates. The measured seasonal average a for the maize canopy was 0.19 in both years. Using a = 0.19 instead of a = 0.23 resulted in 6% overestimation of Rn. Using a = 0.19 instead of a = 0.23 for ETo and ETr estimations, the 6% difference in Rn translated to only 4% and 3% differences in ETo and ETr, respectively, supporting the validity of our hypothesis. Most methods had good correlations with the ASCE-EWRI Rn (r2 > 0.95). The root mean square difference (RMSD) was less than 2 MJ m-2 d-1 between 12 methods and the ASCE-EWRI Rn at Clay Center and between 14 methods and the ASCE-EWRI Rn at Davis. The performance of some methods showed variations between the two climates. In general, r2 values were higher for the semi-arid climate than for the sub-humid climate. Methods that use dynamic e as a function of mean air temperature performed better in both climates than those that calculate e using actual vapor pressure. The ASCE-EWRI-estimated Rn values had one of the best agreements with the measured Rn (r2 = 0.93, RMSD = 1.44 MJ m-2 d-1), and estimates were within 7% of the measured Rn. The Rn estimates from six methods, including the ASCE-EWRI, were not significantly different from measured Rn. Most methods underestimated measured Rn by 6% to 23%. Some of the differences between measured and estimated Rn were attributed to the poor estimation of Rnl. We conducted sensitivity analyses to evaluate the effect of Rnl on Rn, ETo, and ETr. The Rnl effect on Rn was linear and strong, but its effect on ETo and ETr was subsidiary. Results suggest that the Rn data measured over green vegetation (e.g., irrigated maize canopy) can be an alternative Rn data source for ET estimations when measured Rn data over the reference surface are not available. In the absence of measured Rn, another alternative would be using one of the Rn models that we analyzed when all the input variables are not available to solve the ASCE-EWRI Rn equation. Our results can be used to provide practical information on which method to select based on data availability for reliable estimates of daily Rn in climates similar to Clay Center and Davis.

Transcriptional regulation by the orphan nuclear receptor ERRgamma

The nuclear receptor (NR) superfamily is comprised of receptors for small lipopfilic ligands such as steroid hormones, thyroid hormone, retinoids, and vitamin D. NRs are ligand-inducible transcription factors capable of both activating and repressing their target gene expression. They control a wide range of biological functions connected to growth, development, and homeostasis. In addition to the ligand-regulated receptors, the family includes a large group of receptors whose physiological ligands are unknown. These receptors are referred to as orphan NRs. Estrogen-related receptor gamma (ERRgamma) belongs to the ERR subfamily of orphan NRs together with the related ERRalpha and ERRbeta. ERRs share amino acid sequence homology with the classical estrogen receptors (ERs) but they are unable to bind natural estrogenic ligands. ERRgamma is expressed in several embryonic and adult tissues but its biological role is still largely unknown. ERRgamma activates reporter gene expression in transfected cells independently of added hormones implying that ERRgamma harbors constitutive activity. However, the intrinsic activity of ERRgamma can be inhibited by synthetic compounds such as the selective estrogen receptor modulator 4-hydroxytamoxifen (4-OHT). Ligands of NRs can act as agonists that activate transcription, as antagonists that prevent activation of transcription, or as inverse agonists that antagonize the constitutive transcriptional activity of receptor. Most of the synthetic ERRgamma ligands act as inverse agonists but recently, a synthetic ERRgamma agonist GSK4716 was identified. This demonstrates that it is possible to design and identify agonists for ERRgamma. Prior to this thesis work, the structural and functional characteristics of ERRgamma were largely unknown. The aim of this study was to define the functional requirements for ERRgamma-mediated transcriptional regulation and to examine the cross-talk between ERRgamma and other NRs. Due to the fact that natural physiological ligands of ERRgamma are unknown, another aim of this study was to seek new natural compounds that may affect transcriptional activity of ERRgamma. Plant-derived phytoestrogens have previously been shown to act as ligands for ERs and ERRalpha, and therefore the effects of these compounds were also studied on ERRgamma-mediated transcriptional regulation. This work demonstrated that ERRgamma-mediated transcriptional regulation was dependent on DNA-binding, dimerization and activation function-2. Heterodimerization with ERRalpha inhibited the transcriptional activity of ERRgamma. In addition to 4-OHT, another anti-estrogen, 4-hydroxytoremifene (4-OHtor), was identified as an inverse agonist of ERRgamma. Interestingly, ERRgamma activated transcription in the presence of 4-OHT and 4-OHtor on activator protein-1 binding sites. ERRgamma was found to interact with another orphan NR Nurr1 by repressing the ability of Nurr1 to activate transcription of the osteopontin gene. Transcriptional activity of ERRgamma was shown to be stimulated by the phytoestrogen equol. Structural model analysis and mutational experiments indicated that equol was able to bind to the ligand binding domain of ERRgamma. The growth inhibitory effect of ERRgamma on prostate cancer cells was found to be enhanced by equol. In summary, this study demonstrates that despite the absence of an endogenous physiological ligand, the activity of ERRgamma can be modulated in other ways such as dimerization with related receptors or by cross-talk with other transcription factors as well as by binding some synthetic or natural compounds.

Nuclear magnetic resonance spectra of oriented bicyclic systems containing heteroatom(s):the spectrum of 2-thiocoumarin

From the proton nmr studies of 2-thiocoumarin and coumarin, it is concluded that the relative interproton distances in the two oxygen heteroatom bicyclic systems are similar. The values for the phenyl ring protons do not deviate significantly from the regular hexagonal geometry, unlike bicyclic systems with nitrogens as the heteroatoms, such as diazanaphthalenes. Larger values of the indirect spin-spin couplings within the protons of the ring containing the oxygen heteroatom, compared to the values between the ortho protons in the phenyl rings in coumarin and 2-thiocoumarin, correspond to the olefinic nature of these protons. This is in contrast to results for the nitrogen heterocycles where both the rings are aromatic.

Orphan nuclear receptor subfamily NR4A their interplay with other nuclear receptors and functions in osteoblasts

Nurr1, NGFI-B and Nor1 (NR4A2, NR4A1 and NR4A3, respectively) belong to the NR4A subfamily of nuclear receptors. The NR4A receptors are orphan nuclear receptors which means that activating or repressing ligands for these receptors have not been found. NR4A expression is rapidly induced in response to various stimuli including growth factors and the parathyroid hormone (PTH). The studies concerning the NR4A receptors in the central nervous system have demonstrated that they have a major role in the development and function of the dopaminergic neurons of the midbrain and in regulating hypothalamus-pituitary-adrenal-axis. However, the peripheral functions of the NR4A family are largely unknown. Cultured mouse primary osteoblasts, a preosteoblastic cell line and several osteoblastic cell lines were used to investigate the role of NR4A receptors in osteoblasts. NR4A receptors were shown to directly bind to and activate the promoter of the osteopontin gene (OPN) in osteoblastic cells, thus regulating its expression. OPN is a major bone matrix protein expressed throughout the differentiation of preosteoblastic cells into osteoblasts. The activation of the OPN promoter was shown to be dependent on the activation function-1 located in the N-terminal part of Nurr1 and to occur in both monomeric and RXR heterodimeric forms of NR4A receptors. Furthermore, PTH was shown to upregulate OPN expression through the NR4A family. It was also demonstrated that the fibroblast growth factor-8b (FGF-8b) induces the expression of NR4A receptors in osteoblasts as immediate early genes. This induction involved phosphatidylinositol-3 kinase, protein kinase C, and mitogen activated protein kinase, which are all major pathways of FGF signalling. Nurr1 and NGFI-B were shown to induce the proliferation of preosteoblastic cells and to reduce their apoptosis. FGF-8b was shown to stimulate the proliferation of osteoblastic cells through the NR4A receptors. These results suggest that NR4A receptors have a role both in the differentiation of osteoblasts and in the proliferation and apoptosis of preosteoblast. The NR4A receptors were found to bind to the same response element on OPN as the members of the NR3B family of orphan receptors do. Mutual repression was observed between the NR4A receptors and the NR3B receptors. This repression was shown to be dependent on the DNA-binding domains of both receptor families, but to result neither from the competition of DNA binding nor from the competition for coactivators. As the repression was dependent on the relative expression levels of the NR4As and NR3Bs, it seems likely that the ratio of the receptors mediates their activity on their response elements. Rapid induction of the NR4As in response to various stimuli and differential expression of the NR3Bs can effectively control the gene activation by the NR4A receptors. NR4A receptors can bind DNA as monomers, and Nurr1 and NGFI-B can form permissive heterodimers with the retinoid X receptor (RXR). Permissive heterodimers can be activated with RXR agonists, unlike non-permissive heterodimers, which are formed by RXR and retinoic acid receptor or thyroid hormone receptor (RAR and TR, respectively). Non-permissive heterodimers can only be activated by the agonists of the heterodimerizing partner. The mechanisms behind differential response to RXR agonists have remained unresolved. As there are no activating or repressing ligands for the NR4A receptors, it would be important to find out, how they are regulated. Permissiviness of Nurr1/RXR heterodimers was linked to the N-terminal part of Nurr1 ligand-binding domain. This region has previously been shown to mediate the interaction between NRs and corepressors. Non-permissive RAR and TR, permissive Nurr1 and NGFI-B, and RXR were overexpressed with corepressors silencing mediator for retinoic acid and thyroid hormone receptors (SMRT), and with nuclear receptor corepressor in several cell lines. Nurr1 and NGFI-B were found to be repressed by SMRT. The interaction of RXR heterodimers with corepressors was weak in permissive heterodimers and much stronger in non-permissive heterodimers. Non-permissive heterodimers also released corepressors only in response to the agonist of the heterodimeric partner of RXR. In the permissive Nurr1/RXR heterodimer, however, SMRT was released following the treatment with RXR agonists. Corepressor release in response to ligands was found to differentiate permissive heterodimers from non-permissive ones. Corepressors were thus connected to the regulation of NR4A functions. In summary, the studies presented here linked the NR4A family of orphan nuclear receptors to the regulation of osteoblasts. Nurr1 and NGFI-B were found to control the proliferation and apoptosis of preosteoblasts. The studies also demonstrated that cross-talk with the NR3B receptors controls the activity of these orphan receptors. The results clarified the mechanism of permissiviness of RXR-heterodimers. New information was obtained on the regulation and functions of NR4A receptors, for which the ligands are unknown.

Chlorine-35 Nuclear Quadrupole Resonance Studies in 2,3- and 3,5-Dichloroanisoles

The temperature variation of the 3’Cl n.q.r. frequencies in 3,5- and 2,3- dichloroanisoles has been reported here. Both compounds show two lines each, and these have been assigned to the two chlorines in the same molecule with the help of the additive model for the substituent effect. The temperature dependence has been analysed in terms of Bayer-Kushida-Brown model.The torsional frequencies and their temperature dependence have been calculated numerically under a two-mode approximation. 0.n comparing the results in 3,5-dichloroanisole with those in 3,5-dichlorophenol it can be seen that they show similar behaviour owing to the absence of hydrogen bonding in both.

Nuclear Magnetic-Resonance Spectra Of Oriented Biologically Important Molecules - The Structure Of And The Internal-Rotation In N,N-Dimethyluracil

From the proton NMR spectra of Nfl-dimethyluracil oriented in two different nematic solvents, the internal rotation of the methyl groups about the N-C bonds is studied. It has been observed that the preferred conformation of the methyl group having one carbonyl in the vicinity is the one where a C-H bond is in the ring plane pointing toward the carbonyl group. The results are not sensitive to the mode of rotation of the other methyl group. These data are interpreted in terms of the bond polarizations.

1H and 13C nuclear magnetic resonance studies on X-537A (lasalocid-A)-calcium complexes: observation of a sandwich complex

Studies on the conformational and binding characteristics of the ionophoric antibiotic X-537A (lasalocid-A)�calcium ion complexes have been carried out in deuteriated acetonitrile (CD3 CN) using proton and carbon-13 nuclear magnetic resonance (1 H and 13C n.m.r.) spectroscopy. Detailed analysis of the salt-induced chemical shifts at various X-537A to calcium concentration ratios indicated that X-537A forms charged complexes with calcium with 2 : 1 and 1 : 1 stoicheiometries. The conformational model for the complex based on the n.m.r. data showed that the calcium ion is preferentially bound to one end of the molecule, which is binding to three oxygen atoms, the other end (the salicylic acid part) being relatively free. In the 2 : 1 (sandwich) complex, the calcium ion is sandwiched between two X-537A molecules with three oxygen atoms binding to it from each molecule.