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The direct random-phase approximation (dRPA) is used to calculate and compare atomization energies for the HEAT set and ten selected molecules of the G2-1 set using both plane waves and Gaussian-type orbitals. We describe detailed procedures to obtain highly accurate and well converged results for the projector augmented-wave method as implemented in the Vienna Ab initio Simulation Package as well as the explicitly correlated dRPA-F12 method as implemented in the TURBOMOLE package. The two approaches agree within chemical accuracy (1 kcal/mol) for the atomization energies of all considered molecules, both for the exact exchange as well as for the RPA. The root mean-square deviation is 0.41 kcal/mol for the exact exchange (evaluated using density functional theory orbitals) and 0.33 kcal/mol for exact exchange plus correlation from the RPA. [ABSTRACT FROM AUTHOR]

Canola (Brassica napus L.) production is threatened by blackleg disease caused by Leptosphaeria maculans. Disease outcome is determined by interactions among pathogens, plants, farming practices, and environmental factors. Although the gene-for-gene interactions between the pathogen and its plant host are relatively clear, how precisely the pathogen interacts with the environment and farming practices is still poorly understood, making disease forecasting challenging for commercial farmlands. In recent years, artificial intelligence (AI) has been successful in forecasting disease risks based on environmental factors. In this study, we evaluated two AI methods and a data augmentation method to forecast disease risk using a dataset collected from 116 farmlands in Alberta in 2021 and 2022. We first assessed a machine learning model (support vector machine or SVM) and a deep-learning model (convolutional neural network or CNN) to predict blackleg severity based on five weather variables, flea beetle damage, root maggot damage, and crop-rotation variables. Both SVM and CNN predicted the disease risk with an accuracy of over 66%. The data augmentation method did not improve model performance. Flea beetle feeding and maggot damage contribute little to the model's performance, and omitting these data did not appear to affect the results. In contrast, crop rotation contributes substantially to model performance. The five weather variables contribute roughly equally to the model's performance, and removing any of the individual weather variables did not impact prediction ability for both models. [ABSTRACT FROM AUTHOR]

With a He– H 3 + interaction potential obtained from advanced electronic structure calculations, we computed the vibration-rotation-tunneling (VRT) states of this complex for total angular momenta J from 0 to 9, both for the vibrational ground state and for the twofold degenerate v2 = 1 excited state of H 3 + . The potential has three equivalent global minima with depth De = 455.3 cm−1 for He in the plane of H 3 + , three equatorial saddle points that separate these minima with barriers of 159.5 cm−1, and two axial saddle points with energies of 243.1 cm−1 above the minima. The dissociation energies calculated for the complexes of He with ortho- H 3 + (o H 3 + ) and para- H 3 + (p H 3 + ) are D0 = 234.5 and 236.3 cm−1, respectively. Wave function plots of the VRT states show that they may be characterized as weakly hindered internal rotor states, delocalized over the three minima in the potential and with considerable amplitude at the barriers. Most of them are dominated by the jk = 10 and 11 rotational ground states of o H 3 + and p H 3 + , with the intermolecular stretching mode excited up to v = 4 inclusive. However, we also found excited internal rotor states: 33 in He–o H 3 + , and 22 and 21 in He–p H 3 + . The VRT levels and wave functions were used to calculate the frequencies and line strengths of all allowed v2 = 0 → 1 rovibrational transitions in the complex. Theoretical spectra generated with these results are compared with the experimental spectra in Paper II [Salomon et al., J. Chem. Phys. 156, 144308 (2022)] and are extremely helpful in assigning these spectra. This comparison shows that the theoretical energy levels and spectra agree very well with the measured ones, which confirms the high accuracy of our ab initio He– H 3 + interaction potential and of the ensuing calculations of the VRT states. [ABSTRACT FROM AUTHOR]

To determine medical school characteristics that may result in graduates entering the specialty of public health and general preventive medicine (PH&GPM), the authors conducted an analysis comparing the presence of affiliated preventive medicine residency programs and combined Master of Public Health degree programs with the likelihood of graduates entering the specialty of PH&GPM. Using data from the American Board of Preventive Medicine and publicly available information on medical schools and residencies, in spring 2022, the authors compared medical schools that produced PH&GPM physicians with the presence of a PH&GPM residency program, the presence of any preventive medicine residency (public health and general preventive medicine or occupational medicine or aerospace medicine), and the presence of a combined Doctor of Medicine‒Master of Public Health or Doctor of Osteopathic Medicine‒Master of Public Health program. Between 2017 and 2021, there were 385 physicians newly board certified in PH&GPM, 210 medical schools, and 75 preventive medicine residencies. The 385 physicians graduated from 110 of the 210 medical schools. Analyses showed statistically significant associations between medical schools that graduated PH&GPM physicians and the presence of PH&GPM residencies (OR=3.74; 95% CI=1.61, 8.69), all preventive medicine residencies (OR=2.75; 95% CI=1.37, 5.51), and combined degree programs (OR=4.37; 95% CI=2.45, 7.79). Because PH&GPM residency programs affiliated with medical schools are a significant factor associated with PH&GPM physicians obtaining board certification, such analyses may provide critical guidance in the utilization of resources intended to produce more physicians certified in this specialty. [ABSTRACT FROM AUTHOR]

Small patches of habitat for indigenous species that remain in developed landscapes are predicted to lose species over time as extinction debts are paid off and to become transformed by spillover from intensive land uses. In December 2020 we searched for plants of three inland South Island-endemic species of Lepidium (Brassicaceae; L. kirkii, L. sisymbrioides, and L. solandri) at previously known locations in Central Otago, the Waitaki Valley, the Mackenzie Basin, and Kura Tāwhiti (Castle Hill, North Canterbury). We recorded whether Lepidium populations remained and identified the vascular plant flora of each location. Lepidium kirkii was found at six of 14 locations where formerly known and at one new location, but numbered over 50 individuals at only one of these locations. Lepidium sisymbrioides was found at five of six locations visited, but we found fewer than four individuals at three of these locations. L. solandri was found at five of 12 formerly known locations in Central Otago (but numbered over 50 individuals at only one), at five of five formerly known locations on public land in the Mackenzie Basin, and at the one known location at Kura Tāwhiti. Exotic vascular plant species outnumbered native species at all but one Lepidium location in Central Otago and at Kura Tāwhiti, but not in the Mackenzie Basin, where there had been the least habitat loss and land-use intensification. Our results are consistent with theoretical predictions of more local plant extinctions at Lepidium locations, and greater transformation of their habitats, in landscapes dominated by intensive land uses and non-indigenous vegetation. We conclude that intensive ex situ and in situ management is now needed to avoid global extinctions of L. kirkii and L. sisymbrioides, and local extinctions of L. solandri at remaining Central Otago locations and at Kura Tāwhiti. We do not know whether landscape-scale processes still provide for the persistence of L. solandri and other dryland species in the Mackenzie Basin or whether intensive land use has already crossed ecological thresholds. [ABSTRACT FROM AUTHOR]

The carbon chain ions HC 3 O + and HC 3 S + – longer variants of the famous 'X-ogen' line carrier HCO + – have been observed for the first time using two cryogenic 22-pole ion trap apparatus (FELion, Coltrap) and two different light sources: the Free Electron Laser for Infrared eXperiments (FELIX), which was operated between 460 and 2500 cm − 1 , and an optical parametric oscillator operating near 3200 cm − 1 ; signals from both experiments were detected by infrared predissociation action spectroscopy. The majority of vibrational fundamentals were observed for both ions and their wavenumbers compare very favourably with results from high-level anharmonic force field calculations performed here at the coupled-cluster singles and doubles level augmented by a perturbative treatment of triple excitations, CCSD(T). As the action scheme employed here probes the Ne-tagged weakly bound variants, Ne–HC 3 O + and Ne–HC 3 S + , corresponding calculations of these systems were also performed. Differences in the structures and molecular force fields between the bare ions and their Ne-tagged complexes are found to be very small. [ABSTRACT FROM AUTHOR]

New Zealand has a unique opportunity to reshape the future of 1.2 million hectares, or 5% of the country. Since 1990, land clearance and development in the South Island high country have removed large areas of native vegetation, destroying already tenuous endemic species populations, and rare and threatened ecosystems. Important ecosystems and ecological values have been subtly or dramatically degraded through tenure review, discretionary consents, and invasions of plant and animal pests. Natural heritage has been transferred from public to private ownership, and a pest management burden created for future generations. Here, we argue that high country land administration has followed the 'give-hope-defend' model of governance. For 25 years, successive governments gave decision-making power to officials in Land Information New Zealand and Department of Conservation. Governments then hoped officials would follow ambiguous statutory direction. All the while, governments ignored their governance responsibilities by assiduously defending officials' freedom from public accountability for decisions that the public found nonsensical. Indeed the Commissioner of Crown Lands, with whom the proverbial buck stops, is accountable to neither the Minister nor the public. We conclude that if the government wants enduring stewardship in the high country, revised legislation needs clarity of purpose and accountability to the public. [ABSTRACT FROM AUTHOR]

This paper will summarize the Newton-Leibniz controversy and how it relates to Green's [24] paper, Green's background and the influence of John Toplis, and the methods we used in exploring the Nottingham Subscription Library archives. Newton and Leibniz each claimed to have discovered calculus first, with Newton publicly accusing Leibniz of copying his ideas in 1711, although Leibniz managed to prevent criminal charges being brought against him (Sastry, [45]). The inclusion of Cavendish suggests very strongly that Green was able to understand I both i Newtonian fluxions and Leibnizian calculus, as well as the variational calculus of Lagrange. Green's use of European calculus in his 1828 essay signaled a bigger change in British mathematics away from Newton's fluxion methods, embracing European calculus to the ultimate benefit of the British mathematical and scientific communities. [Extracted from the article]

We report two experiments that used smartphone applications for presenting and recalling verbal stimuli over extended timescales. In Experiment 1, we used an iPhone application that we had developed, called RECAPP-XPR, to present 76 participants with a single list of eight words presented at a rate of one word every hour, followed by a test of free recall an hour later. The experiment was exceptionally easy to schedule, taking only between 5 and 10 min to set up using a web-based interface. RECAPP-XPR randomly samples the stimuli, presents the stimuli, and collects the free recall data. The stimuli disappear shortly after they have been presented, and RECAPP-XPR collects data on when each stimulus was viewed. In Experiment 2, the study was replicated using the widely used image-sharing application Snapchat. A total of 197 participants were tested by 38 student experimenters, who manually presented the stimuli as "snaps" of experimentally controlled stimuli using the same experimental rates that had been used in Experiment 1. Like all snaps, these stimuli disappeared from view after a very short interval. In both experiments, we observed significant recall advantages for the first and last list items (primacy and recency effects, respectively), and there were clear tendencies to make more transitions at output between near-neighboring items, with a forward-ordered bias, consistent with temporal contiguity effects. The respective advantages and disadvantages of RECAPP-XPR and Snapchat as experimental software packages are discussed, as is the relationship between single-study-list smartphone experiments and long-term recency studies of real-world events. [ABSTRACT FROM AUTHOR]

The high accuracy extrapolated ab initio thermochemistry (HEAT) protocol is applied to compute the total atomization energy (TAE) and the heat of formation of benzene. Large-scale coupled-cluster calculations with more than 1500 basis functions and 42 correlated electrons as well as zero-point energies based on full cubic and (semi)diagonal quartic force fields obtained with the coupled-cluster singles and doubles with perturbative treatment of the triples method and atomic natural orbital (ANO) triple- and quadruple-zeta basis sets are presented. The performance of modifications to the HEAT scheme and the scaling properties of its contributions with respect to the system size are investigated. A purely quantum-chemical TAE and associated conservative error bar of 5463.0 ± 3.1 kJ mol-1 are obtained, while the corresponding 95% confidence interval, based on a statistical analysis of HEAT results for other and related molecules, is ± 1.8 kJ mol-1. The heat of formation of benzene is determined to be 101.5 ± 2.0 kJ mol-1 and 83.9 ± 2.1 kJ mol-1 at 0 K and 298.15 K, respectively. [ABSTRACT FROM AUTHOR]

Results of large-scale coupled-cluster calculations of selected C2H2Si and CNHSi structural isomers are reported. Equilibrium molecular structures of a total of 12 molecules in their singlet electronic states have been calculated systematically employing the coupled-cluster singles and doubles model augmented by a perturbative correction for triple excitations (CCSD(T)) in combination with Dunning’s hierarchy of correlation consistent basis sets. In addition, anharmonic force fields were calculated to yield fundamental vibrational frequencies and rotation-vibration interaction constants αiA,B,C. The latter were used to determine empirical equilibrium structures reemp of two molecules — silacyclopropenylidene, c-C2H2Si, and silapropadienylidene, H2CCSi — for which sufficient isotopic data are available from literature. Very good agreement with theoretical equilibrium structures from CCSD(T) calculations employing core-valence basis sets of quadruple and quintuple-zeta quality — i.e., cc-pwCVQZ (337 basis functions), cc-pCV5Z, and cc-pwCV5Z (581 basis functions) is found — to within 0.001 Å for bond lengths and 0.1° for bond angles. Theoretical ground state rotational constants of HSiCN and HSiNC compare very favorably with experimental microwave data from literature, to within 0.15% (HSiCN) and 0.1% (HSiNC) for the B0 and C0 rotational constants. In the case of c-C2H2Si and H2CCSi this agreement is even better than 0.1%. For the latter two molecules effects of higher-level electron-correlation and relativity to the equilibrium geometry as well as the electronic contributions to the rotational constants are investigated. For eight molecules not yet studied at high spectral resolution in the gas-phase theoretical molecular parameters are provided to support future laboratory investigations. Theoretical vibrational fundamentals compare well with data of eight species studied previously with infrared matrix isolation spectroscopy. [ABSTRACT FROM AUTHOR]

Benchmark calculations of 19F nuclear magnetic shielding constants are presented for a set of 28 molecules. Near-quantitative accuracy (ca. 2 ppm deviation from experiment) is achieved if (1) electron correlation is adequately treated by employing the coupled-cluster singles and doubles (CCSD) model augmented by a perturbative correction for triple excitations [CCSD(T)], (2) large (uncontracted) basis sets are used, (3) gauge-including atomic orbitals are used to ensure gauge-origin independence, (4) calculations are performed at accurate equilibrium geometries [obtained from CCSD(T)/cc-pVTZ calculations correlating all electrons], and (5) vibrational averaging and temperature corrections via second-order vibrational perturbation theory (VPT2) are included. For the CCSD(T)/13s9p4d3f calculations corrected for vibrational effects, mean and standard deviation from experiment are -1.9 and 1.6 ppm, respectively. Less elaborate theoretical treatments result in larger errors. Consideration of relative shifts can reduce the mean deviation (through an appropriately chosen reference compound), but does not change the standard deviation. Density-functional theory calculations of absolute and relative 19F nuclear magnetic shielding constants are found to be, at best, as accurate as the corresponding Hartree–Fock self-consistent-field calculations and are not improved by consideration of vibrational effects. Molecular systems containing fluorine-oxygen, fluorine-nitrogen, and fluorine-fluorine bonds are found to be more challenging than the other investigated molecules for the considered theoretical methods. [ABSTRACT FROM AUTHOR]

Effects of increased basis-set size as well as a correlated treatment of the diagonal Born-Oppenheimer approximation are studied within the context of the high-accuracy extrapolated ab initio thermochemistry (HEAT) theoretical model chemistry. It is found that the addition of these ostensible improvements does little to increase the overall accuracy of HEAT for the determination of molecular atomization energies. Fortuitous cancellation of high-level effects is shown to give the overall HEAT strategy an accuracy that is, in fact, higher than most of its individual components. In addition, the issue of core-valence electron correlation separation is explored; it is found that approximate additive treatments of the two effects have limitations that are significant in the realm of <1 kJ mol-1 theoretical thermochemistry. [ABSTRACT FROM AUTHOR]

AbstractPotato is a vital crop worldwide and its production is threatened by diseases caused by viruses, bacteria, fungi and other forms of microorganisms. Early detection and identification of these pathogens are essential to control their spread and minimize yield losses. Improvements in detection and identification have come as molecular detection techniques have been developed, such as Enzyme-Linked Immunosorbent Assay (ELISA), Polymerase Chain Reaction (PCR), Quantitative real-time PCR (qPCR), RNase H-dependent PCR (rhPCR) and Loop-Mediated Isothermal Amplification (LAMP). In this review, the mechanisms of these molecular techniques are discussed. These techniques have revolutionized the diagnosis and management of potato diseases. They offer high sensitivity, specificity and rapid detection, making them invaluable tools for disease surveillance and diagnosis. However, further development and optimization of these techniques, and novel techniques such as artificial intelligence, will undoubtedly contribute to more effective disease diagnosis, management and the protection of potato crops. [ABSTRACT FROM AUTHOR]

Surveys of pulse crops across the Canadian prairies were undertaken between 2014 and 2017 to assess the distribution and severity of root rot of field pea and lentil, to identify the most important causal agents, and to compare the efficiency of culturing techniques with multiplex PCR. Root rot was present in every pea and lentil field surveyed in all three provinces. When assessed based on province and soil zone, moderate to severe symptoms (severity > 3 on a 1-7 scale) occurred in 25-99% of pea fields, but only 8-34% of lentil fields. Root rot severity on both crops was higher in growing seasons with high precipitation and was lower in drier years, but only lentil showed any difference associated with soil zone, with lower severity in the brown soil zone. This study demonstrated that Aphanomyces euteiches occurs across the Prairie region, where it caused moderate to severe injury on many field pea crops. Fusarium avenaceum was the most common pathogen identified in both culturing and PCR analyses, but other Fusarium spp., together with Pythium spp. and Rhizoctonia solani, were also components of the complex. Use of PCR for pathogen identification routinely resulted in identification of many pathogens from an infected root, whereas culturing and isolation resulted in only one or two pathogens per root. PCR was extremely important for assessing the impact of A. euteiches, which was almost never identified using culturing approaches. This observation explains why A. euteiches was not initially recognized as an important pathogen of pulses in the region. [ABSTRACT FROM AUTHOR]

Goss’s bacterial wilt and leaf blight, caused by Clavibacter nebraskensis (syn. C. michiganensis subsp. nebraskensis), is a serious disease of corn. It is not new to North America, but in 2006, the number of outbreaks increased and the pathogen was reported in areas of the USA and Canada where it had not previously been found. The disease is increasing in distribution and severity and new areas such as the northern Prairies may be at higher risk as corn production acreage rises. Therefore, Goss’s wilt monitoring and subsequent management should be priorities in areas where the disease has appeared relatively recently, such as the Canadian Prairie provinces. This update summarizes the current status of Goss’s bacterial wilt and leaf blight in Canada including its geographic distribution as determined through recent monitoring activities and new detection methods. It also discusses current knowledge regarding pathogen biology, disease development, epidemiology and management. [ABSTRACT FROM AUTHOR]

This paper examines the notion of self-belief in young athletes and its role in maintaining good performance. We draw on the concept of self-efficacy (Bandura, 1990, 1997) and suggest that revisions to Bandura's original model to improve its explanatory power, particularly in a sporting context. We believe that the addition of two interpersonal components (see Lent & Lopez, 2002) can guide the communication skills of coaches and members of their support team, such as physiotherapists. A fictitious case illustration is used as a vehicle to show how the above concepts can be used in a clinical situation where a young athlete was displaying performance anxiety which, in part, resulted from the poor communication skills of the athlete's support team (coach and physiotherapist). We make recommendations about how the communication can be improved. [ABSTRACT FROM AUTHOR]

Enthalpies of formation of the cyanonitrene radical, NCN, were calculated according to the HEAT ( H igh-accuracy E xtrapolated A b initio T hermochemistry) protocol. The obtained, recommended values are 451.7 ± 1.0 kJ mol −1 and 452.2 ± 1.0 kJ mol −1 at 0 K and 298.15 K, respectively (gas phase, 1 bar). The calculated values are in agreement with the most recent Active Thermochemical Tables analysis and some of the previous experimental and computational results. The uncertainties associated with the HEAT values are, however, considerably smaller. [ABSTRACT FROM AUTHOR]

Semi-experimental equilibrium and high-level quantum-chemical structures are reported for three hydrocarbons containing the vinyl (H 2 C = CH–) group: vinyl acetylene, vinyl diacetylene and vinyl cyanide. Semi-experimental equilibrium structures have been obtained through a combination of new experimental results from Fourier transform microwave spectroscopy combined with force field calculations performed at the coupled-cluster singles and doubles model augmented by a perturbative correction for triple excitations, CCSD(T), level of theory. Comparison against equilibrium structures obtained by high-level CCSD(T) computations employing large correlation-consistent basis sets with up to 1090 basis functions yields excellent agreement. From this combined study, we find the carbon atom backbone in the vinyl group is largely unaffected when bound to different substituents, such as –H, –CCH, –C 4 H, –CN. [ABSTRACT FROM AUTHOR]

Optimised auxiliary basis sets for lanthanide atoms (Ce to Lu) for four basis sets of the Karlsruhe error-balanced segmented contracted def2 - series (SVP, TZVP, TZVPP and QZVPP) are reported. These auxiliary basis sets enable the use of the resolution-of-the-identity (RI) approximation in post Hartree-Fock methods - as for example, second-order perturbation theory (MP2) and coupled cluster (CC) theory. The auxiliary basis sets are tested on an enlarged set of about a hundred molecules where the test criterion is the size of the RI error in MP2 calculations. Our tests also show that the same auxiliary basis sets can be used together with different effective core potentials. With these auxiliary basis set calculations of MP2 and CC quality can now be performed efficiently on medium-sized molecules containing lanthanides. [ABSTRACT FROM AUTHOR]

The vertical ionisation energies of the molecules of the GW27 (27 molecules) and GW100 (100 molecules) test sets are computed in a polarised triple-zeta-valence basis set in the framework of coupled-cluster theory with single, double, and non-iterative triple substitutions. The molecular geometries were kept fixed to those of the two test sets. To demonstrate the usefulness of the coupled-cluster reference values, they are compared with quasi-particle energies obtained in the G0W0approximation for functionals commonly used in Kohn–Sham density-functional theory (DFT). Furthermore, an approximation is assessed, in which only exchange contributions are added to the DFT orbital energies. [ABSTRACT FROM PUBLISHER]

An up-to-date overview of the CFOUR program system is given. After providing a brief outline of the evolution of the program since its inception in 1989, a comprehensive presentation is given of its well-known capabilities for high-level coupled-cluster theory and its application to molecular properties. Subsequent to this generally well-known background information, much of the remaining content focuses on lesser-known capabilities of CFOUR, most of which have become available to the public only recently or will become available in the near future. Each of these new features is illustrated by a representative example, with additional discussion targeted to educating users as to classes of applications that are now enabled by these capabilities. Finally, some speculation about future directions is given, and the mode of distribution and support for CFOUR are outlined. [ABSTRACT FROM AUTHOR]

Thephotophysics of chromophores is strongly influenced by theirenvironment. Solvation, charge state, and adduct formation significantlyaffect ground and excited state energetics and dynamics. The presentstudy reports on fluorescence emission of rhodamine B cations (RhBH+) and derivatives in the gas phase. Substitution of the acidicproton of RhBH+by alkali metal cations, M+,ranging from lithium to cesium leads to significant and systematicblue shifts of the emission. The gas-phase structures and singlettransition energies of RhBH+and RhBM+, M =Li, Na, K, Rb, and Cs, were investigated using Hartree–Focktheory, density functional methods, second-order Møller–Plessetperturbation theory, and the second-order approximate coupled-clustermodel CC2. Comparison of experimental and theoretical results highlightsthe need for improved quantum chemical methods, while the hypsochromicshift observed upon substitution appears best explained by the Starkeffect due to the inhomogeneous electric field generated by the alkaliions. [ABSTRACT FROM AUTHOR]

We present gas-phase dispersed photoluminescencespectra of europium(III) 9-hydroxyphenalen-1-one (HPLN) complexesforming adducts with alkali metal ions ([Eu(PLN)3M]+with M = Li, Na, K, Rb, and Cs) confined in a quadrupoleion trap for study. The mass selected alkali metal cation adductsdisplay a split hypersensitive 5D0→ 7F2Eu3+emission band. One of the twoemission components shows a linear dependence on the radius of thealkali metal cation whereas the other component displays a quadraticdependence thereon. In addition, the relative intensities of bothcomponents invert in the same order. The experimental results areinterpreted with the support of density functional calculations andJudd–Ofelt theory, yielding also structural information onthe isolated [Eu(PLN)3M]+chromophores. [ABSTRACT FROM AUTHOR]

A systematic way to construct compact complementary auxiliary basis sets (ABSs) from and for atomic natural orbital basis sets for the use as resolution-of-the-identity sets in explicitly correlated F12 calculations is presented. The performance of these newly constructed ABSs has been benchmarked in explicitly correlated calculations of absolute energies, ionisation potentials and electron affinities. [ABSTRACT FROM PUBLISHER]

Hypoxia drives malignant progression in part by promoting accumulation of the oncogenic transcription factor hypoxia inducible factor--1α (HIF-1α) in tumor cells. Tumor aggressiveness also relates to elevation of the cancer stem cell--associated membrane protein CD24, which has been causally implicated in tumor formation and metastasis in experimental models. Here, we link these two elements by showing that hypoxia induces CD24 expression through a functional hypoxia responsive element in the CD24 promoter. HIF-1α overexpression induced CD24 mRNA and protein under normoxic conditions, with this effect traced to a recruitment of endogenous HIF-1α to the CD24 promoter. Short hairpin RNA--mediated attenuation of HIF-1α or CD24 expression reduced cancer cell survival in vitro and in vivo at the levels of primary and metastatic tumor growth. CD24 overexpression in HIF-1α--depleted cancer cells rescued this decrease, whereas HIF-1α overexpression in CD24-depleted cells did not. Analysis of clinical tumor specimens revealed a correlation between HIF-1α and CD24 levels and an association of their coexpression to decreased patient survival. Our results establish a mechanistic linkage between 2 critically important molecules in cancer, identifying CD24 as a critical HIF-1α transcriptional target and biologic effector, strengthening the rationale to target CD24 for cancer therapy. [ABSTRACT FROM AUTHOR]

Enthalpies of formation at both 0 and 298 K were calculatedaccordingto the HEAT (High-accuracy Extrapolated Ab initio Thermochemistry)protocol for the title molecules, all of which play important rolesin combustion chemistry. At the HEAT345-(Q) level of theory, recommendedenthalpies of formation at 0 K are 301.5 ± 1.3, 180.3 ±1.8, and 23.4 ± 1.5 kJ mol–1for vinyl, allyl,and vinoxy, respectively. At 298 K, the corresponding values are 297.3,168.6, and 16.1 kJ mol–1, with the same uncertainties.The calculated values for the three radicals are in excellent agreementwith the corresponding experimental values, but the uncertaintiesassociated with the HEAT values for vinoxy are considerably smallerthan those based on experimental studies. [ABSTRACT FROM AUTHOR]

We report vibrationally resolved photoelectron spectra of internally cold HOCO- and DOCO- anions at wavelengths near and well above the detachment threshold. These spectra are dominated by a strong Franck-Condon progression of three low-energy modes of the cis isomer, the first gas-phase measurement of these vibrations. Using highly resolved, near-threshold spectra we are able to reassign the electron affinities (EAs) of cis- and trans-HOCO to 1.51 ± 0.01 and 1.37 ± 0.01 eV, respectively. Using these EAs, well depths with respect to OH + CO are determined to be 1.07 ± 0.02 eV for trans-HOCO and 0.99 ± 0.02 eV for cis-HOCO. High-level ab initio calculations show excellent agreement with all experimental results. These values will be of direct use in thermochemical calculations and will help to aid in the identification of the HOCO radical in complex reactions. [ABSTRACT FROM AUTHOR]

Rho GDP-Dissociation Inhibitors (RhoGDIs) are important regulators of the Rho family of small GTPases. The expression of RhoGDIs is altered in a variety of cancers and they have been shown to mediate several processes during tumorigenesis and cancer progression. Using examples of RhoGDI-mediated signaling and expression patterns in endothelial cells as well as pancreatic, breast, and bladder cancer, the multitude of potential cancer therapeutic targets presented by a better understanding of their function is illustrated. Several novel therapeutic strategies are proposed for intervening in RhoGDI signaling, and potential complications arising from their implementation are discussed. [Copyright &y& Elsevier]

The discovery of biofilm formation in bacteria and yeasts has led to a better understanding of microbial ecology and to new insights into the mechanisms of virulence and persistence of pathogenic microorganisms. However, it is generally assumed that filamentous fungi, some of which have a significant impact on our health or our economy, do not form biofilms. In contrast to this assumption, here we discuss recent findings supporting the hypothesis that surface-associated filamentous fungi can form biofilms. Based on these findings and on previous models for bacterial and yeast systems, we propose preliminary criteria and a model for biofilm formation by filamentous fungi. [Copyright &y& Elsevier]

Abstract: The 4-nitrophenyl ether is an efficient directing group in the asymmetric aminohydroxylation reaction of homoallylic ether derivatives. Either regioisomeric product can be obtained with useful levels of enantioselectivity allowing for the short enantioselective synthesis of GABOB and homoserine derivatives. A model based on substrate-catalyst interactions is presented to explain the regio- and enantioselectivity of the aminohydroxylation reactions. [Copyright &y& Elsevier]

Abstract: High-level quantum-chemical calculations are reported at the MP2 and CCSD(T) levels of theory for the equilibrium structure and the harmonic and anharmonic force fields of diacetylene, Hh name="tbnd" />Ch name="tbnd" />Clculations were performed employing Dunning’s hierarchy of correlation-consistent basis sets cc-pVXZ, cc-pCVXZ, and cc-pwCVXZ, as well as the ANO2 basis set of Almlöf and Taylor. An empirical equilibrium structure based on experimental rotational constants for 13 isotopic species of diacetylene and computed zero-point vibrational corrections is determined and in good agreement with the best theoretical structure (CCSD(T)/cc-pCV5Z: , , ). In addition, the computed fundamental vibrational frequencies are compared with the available experimental data and found in satisfactory agreement. [Copyright &y& Elsevier]

Abstract: The greatest risk for morbidity and mortality caused by bladder cancer is due to metastasis. For this reason, we have developed a paradigm for discovering the molecular mechanisms underlying bladder cancer progression to an invasive and metastatic phenotype. Results of microarray gene expression analysis of a cell culture model were parsed by identifying overlapping genes that correlate with increasing stage and grade of human tumors. One gene identified by this method, RhoGDI2, was tested in various in vitro and in vivo model systems and confirmed to be a metastasis suppressor gene. Using a similar strategy of gene identification by concordance of microarray gene expression results from cells expressing RhoGDI2 and human bladder cancers, two molecular effectors of RhoGDI2 signaling were identified. These targets, endothelin-1 and Neuromedin U are excellent potential targets for therapeutic intervention in the metastatic cascade. [Copyright &y& Elsevier]

A variety of approaches are presented for the computation of atomic and molecular correlation energies based on the Bethe–Salpeter equation in the framework of the adiabatic-connection fluctuation–dissipation theorem. The performance of the approaches is assessed by computing the total energies of the atoms H—Ne and the atomization energies of the high-accuracy extrapolated ab initio thermochemistry set of small molecules as well as by determining the bond lengths and harmonic vibrational frequencies of the metal monoxides MO with M=Ca—Zn. [ABSTRACT FROM AUTHOR]

Background: Signals from a cell's environment are sensed by receptors, which activate pathways that, in turn, transmit the signals to the nucleus, informing decisions on growth, angiogenesis, and other cell functions. Transcription of vascular endothelial growth factor (VEGF), a potent angiogenic factor, can be induced by cell-cell contact. In the current work, we sought to determine if this induction is dependent on transformation of cells to a malignant phenotype and subsequently to determine which signaling molecules mediate activation of VEGF transcription.Methods: Normal and transformed prostate epithelial cell lines were examined at various cell densities to simulate the effect of increased cell contact on expression of VEGF messenger RNA. Transformed cells were also cotransfected with a VEGF promoter-reporter construct and with constructs that express dominant negative or activated versions of signal transduction proteins hypothesized to be involved in the cell-cell contact process, and reporter activity was assessed at various cell densities. All P values are two-sided.Results: Direct cell-cell contact, but not extracellular matrix components, resulted in transcriptional activation of a VEGF promoter-reporter construct in malignant (P<.0001) but not in nonmalignant (P =.37) prostate cells. This process was mediated via a mitogen-activated protein kinase (MAPK); it required the activity of focal adhesion kinase (FAK), Rap1, and Raf and was Ras independent. In addition, transcriptional activation of a Ras-sensitive Elk-1 chimeric reporter by cell-cell contact suggests that Rap1 is a key factor in regulating the specificity of convergent MAPK-signaling pathways arising from different upstream extracellular stimuli.Conclusions: Cell contact induction of VEGF transcription via FAK and Rap1 provides a novel Ras-independent, but transformation-dependent, mechanism for stimulus-specific regulation of tumor VEGF expression via MAPK. [ABSTRACT FROM AUTHOR]

The dietary approach to stop hypertension (DASH) diet combines the antihypertensive effect of a low sodium and high potassium diet. In particular, the potassium component of the diet acts as a switch in the distal convoluted tubule to reduce sodium reabsorption, similar to a diuretic but without the side effects. Previous trials to understand the mechanism of the DASH diet were based on animal models and did not characterize changes in human ion channel protein abundance. More recently, protein cargo of urinary extracellular vesicles (uEVs) has been shown to mirror tissue content and physiological changes within the kidney. We designed an inpatient open label nutritional study transitioning hypertensive volunteers from an American style diet to DASH diet to examine physiological changes in adults with stage 1 hypertension otherwise untreated (Sacks FM, Svetkey LP, Vollmer WM, Appel LJ, Bray GA, Harsha D, Obarzanek E, Conlin PR, Miller ER 3rd, Simons-Morton DG, Karanja N, Lin PH; DASH-Sodium Collaborative Research Group. N Engl J Med 344: 3–10, 2001). Urine samples from this study were used for proteomic characterization of a large range of pure uEVs (small to large) to reveal kidney epithelium changes in response to the DASH diet. These samples were collected from nine volunteers at three time points, and mass spectrometry identified 1,800 proteins from all 27 samples. We demonstrated an increase in total SLC12A3 [sodium-chloride cotransporter (NCC)] abundance and a decrease in aquaporin-2 (AQP2) in uEVs with this mass spectrometry analysis, immunoblotting revealed a significant increase in the proportion of activated (phosphorylated) NCC to total NCC and a decrease in AQP2 from day 5 to day11. This data demonstrates that the human kidney's response to nutritional interventions may be captured noninvasively by uEV protein abundance changes. Future studies need to confirm these findings in a larger cohort and focus on which factor drove the changes in NCC and AQP2, to which degree NCC and AQP2 contributed to the antihypertensive effect and address if some uEVs function also as a waste pathway for functionally inactive proteins rather than mirroring protein changes. NEW & NOTEWORTHY: Numerous studies link DASH diet to lower blood pressure, but its mechanism is unclear. Urinary extracellular vesicles (uEVs) offer noninvasive insights, potentially replacing tissue sampling. Transitioning to DASH diet alters kidney transporters in our stage 1 hypertension cohort: AQP2 decreases, NCC increases in uEVs. This aligns with increased urine volume, reduced sodium reabsorption, and blood pressure decline. Our data highlight uEV protein changes as diet markers, suggesting some uEVs may function as waste pathways. We analyzed larger EVs alongside small EVs, and NCC in immunoblots across its molecular weight range. [ABSTRACT FROM AUTHOR]

Studies the changes in the vegetation communities of three valley mires in Suffolk, England. Tabulation and ordination of floristic records for 1959 and 1991; Factors that accounted for the changes; Significant alteration to mires subjected to hydrological disturbances; Minimal change where ground water influx was reduced; Transformation of derelict mires with undisturbed hydrology.

Abstract: We discuss the equilibrium structure of the hydrogen trioxy radical (HO3). The CCSD(T) geometry at the approximate basis set limit, in conjunction with the geometry obtained using the CCSDT method and a moderate basis set, suggests an equilibrium HO–OO bond length of approximately 1.59Å. [Copyright &y& Elsevier]

• Highly accurate microwave frequencies obtained for HC 5 N. • Improved spectroscopic parameters to facilitate radio astronomical observations. • First determination of 14N spin-rotation parameter and improved quadrupole value. • Some improvement achieved for HC 7 N. • Quantum chemical calculations on hyperfine parameters of HCN to HC 7 N. Very accurate transition frequencies of HC 5 N were determined between 5.3 and 21.4 GHz with a Fourier transform microwave spectrometer. The molecules were generated by passing a mixture of HC 3 N and C 2 H 2 highly diluted in neon through a discharge valve followed by supersonic expansion into the Fabry-Perot cavity of the spectrometer. The accuracies of the data permitted us to improve the experimental 14 N nuclear quadrupole coupling parameter considerably and the first experimental determination of the 14 N nuclear spin-rotation parameter. The transition frequencies are also well suited to determine in astronomical observations the local speed of rest velocities in molecular clouds with high fidelity. The same setup was used to study HC 7 N, albeit with modest improvement of the experimental 14 N nuclear quadrupole coupling parameter. Quantum chemical calculations were carried out to determine 14 N nuclear quadrupole and spin-rotation coupling parameters of HC 5 N, HC 7 N, and related molecules. These calculations included evaluation of vibrational and relativistic corrections to the non-relativistic equilibrium quadrupole coupling parameters; their considerations improved the agreement between calculated and experimental values substantially. [ABSTRACT FROM AUTHOR]

The article discusses medical education provided by the F. Edward Hébert School of Medicine at the Uniformed Services University of the Health Sciences, focusing on pediatrics medicine. It states that student-run Pediatric Interest Group helps to facilitate exposure to the unique field of military pediatrics, and mentions that pediatricians in the Military Health System must attend to stresses associated with frequent relocations. It notes efforts to increase interest in pediatrics.

Food-borne pathogens are a serious challenge in food handling, processing, and packaging systems. The growth of microbial biofilms on food handling surfaces further complicates the management of the microbial contamination of food. Microorganisms within biofilms are difficult to eradicate with chemical disinfectants, with an increased likelihood of survival and the subsequent contamination of food. Therefore, a biofilm approach is needed in food safety and hygiene studies. Since many factors, such as strain, cell density, surface type and texture, environmental stress, and so forth, can affect biofilm formation and disinfectant efficacy, we evaluated the responses of biofilms formed by three food-borne bacterial pathogens on eight hard surfaces to seven chemical disinfectants. The three bacteria showed different capacities to colonize the surfaces. Similarly, chemical disinfectants also varied in efficacy, on surfaces and with pathogen species. One-, two-, and three-way interactions of strain, surface, and disinfectant were observed. The results generated demonstrate that the fine-tuning of sanitization strategies along the food production, processing, and packaging chain can be achieved in specific scenarios by accounting for two- and three-way interactions among bacteria, surface, and disinfectant. [ABSTRACT FROM AUTHOR]

Fungi and bacteria cause disease issues in cultivated plants world-wide. In most cases, the fungi and bacteria colonize plant tissues as biofilms, which can be very challenging to destroy or eradicate. In this experiment, we employed a novel (biofilm) approach to crop disease management by evaluating the efficacies of six fungicides, and four silver-based compounds, versus biofilms formed by fungi and bacteria, respectively. The aim was to identify combinations of fungicides and metallic cations that showed potential to improve the control of white mold (WM), caused by the ascomycete fungus Sclerotinia sclerotiorum, and to evaluate novel high valency silver compounds as seed coatings to prevent biofilm formation of four bacterial blight pathogens on dry bean seeds. Our results confirmed that mature fungal biofilms were recalcitrant to inactivation by fungicides. When metallic cations were added to the fungicides, their efficacies were improved. Some improvements were statistically significant, with one combination (fluazinam + Cu2+) showing a synergistic effect. Additionally, coatings with silver compounds could reduce bacterial blight biofilms on dry bean seeds and oxysilver nitrate was the most potent inhibitor of bacterial blight. [ABSTRACT FROM AUTHOR]

Guided by theoretical predictions, the hyperfine structures of the rotational spectra of mono- and bideuterated-water containing 17O have been experimentally investigated. To reach sub-Doppler resolution, required to resolve the hyperfine structure due to deuterium quadrupole coupling as well as to spin-rotation (SR) and dipolar spin-spin couplings, the Lamb-dip technique has been employed. The experimental investigation and in particular, the spectral analysis have been supported by high-level quantum-chemical computations employing coupled-cluster techniques and, for the first time, a complete experimental determination of the hyperfine parameters involved was possible. The experimentally determined 17O spin-rotation constants of D2 17O and HD17O were used to derive the paramagnetic part of the corresponding nuclear magnetic shielding constants. Together with the computed diamagnetic contributions as well as the vibrational and temperature corrections, the latter constants have been employed to confirm the oxygen nuclear magnetic shielding scale, recently established on the basis of spin-rotation data for H2 17O [ABSTRACT FROM AUTHOR]

The rotationally resolved infrared (IR) spectrum of the He– H 3 + complex has been measured in a cryogenic ion trap experiment at a nominal temperature of 4 K. Predissociation of the stored complex has been invoked by excitation of the degenerate ν2 mode of the H 3 + sub-unit using a pulsed optical parametric oscillator system. An assignment of the experimental spectrum became possible through one-to-one correlations with bands of the spectrum theoretically predicted in Paper I [Harding et al., J. Chem. Phys. 156, 144307 (2022)]. 19 bands have been assigned and analyzed, and the energy term diagram of the lower states of this floppy molecular complex has been derived from combination differences (CDs) in the experimental spectrum. Ground state combination differences (GSCDs) reveal a large part of the energy term diagram for the He– H 3 + complex in its vibrational ground state, v = 0. Experimental and theoretical term energies agree within experimental accuracy for the rotational fine structure associated with the total angular momentum quantum number J and the parity e/f as well as for the coarse spacing of the lowest K states of the complex. This favorable comparison shows that the potential energy surface (PES) calculated in Paper I is accurate. The barriers between the three equivalent global minima in this PES are relatively low and the He– H 3 + complex is extremely floppy, with nearly unhindered internal rotation of the H 3 + sub-unit. The resulting Coriolis interactions couple the internal and end-over-end rotation of the complex and contribute significantly to the energy terms. They are observed both in experiment and theory and are, e.g., the origin of different rotational constants for states of e and f parity. Also in this respect, experiment and theory agree very well. Despite the assignment and analysis of many bands of the extremely rich IR spectrum of He– H 3 + , higher levels of excitation, including the complex stretching mode, need further attention. [ABSTRACT FROM AUTHOR]

The hyperfine structure in the rotational spectrum of water containing 17O has been investigated experimentally and by means of quantum-chemical calculations. The Lamb-dip technique has been used to resolve the hyperfine structure due to spin-rotation as well as spin-spin interactions and allowed the determination of the corresponding hyperfine parameters with high accuracy. The experimental investigation and, in particular, the analysis of the spectra have been supported by quantum-chemical computations at the coupled-cluster level. The experimental 17O isotropic spin-rotation constant of H217O has been used in a further step for the determination of the paramagnetic part of the corresponding nuclear magnetic shielding constant, whereas the diamagnetic contribution as well as vibrational and temperature corrections have been obtained from quantum-chemical calculations. This joint procedure leads to a value of 325.3(3) ppm for the oxygen shielding in H217O at 300 K, in good agreement with pure theoretical predictions, and in this way provides the basis for a new absolute oxygen shielding scale. [ABSTRACT FROM AUTHOR]