Campylobacter and fluoroquinolones: a bias data set?

There is no universally accepted standard method for the isolation of Campylobacter spp. and it is considered that currently available isolation media are not yet optimal for the recovery of Campylobacter spp. from a range of sample types. Almost all methods incorporate antibiotics into the isolation media to inhibit growth of other bacteria within the sample. It is established that the incorporation of such antibiotics into isolation media will inhibit the growth of some Campylobacter spp. as well as other bacteria. The results of the use of such suboptimal isolation methods are that the isolates which 'survive' the isolation procedure will be those which: (i) are able to 'out compete' the rest of the bacteria in the sample, i.e. they are able to grow faster; (ii) are resistant to the antibiotics used in the isolation media; and (iii) are randomly selected by the laboratory technician as being a 'typical'Campylobacter spp. It is clear that such a procedure is intrinsically biased and will mean that species resistant to the antibiotics used in the media will be isolated. This introduces real doubt that the bacteria isolated are truly representative of those initially found on the sample. It is also becoming clear that Campylobacter spp. are rather difficult to isolate as pure cultures and many are in fact mixtures of more than one strain. Again this introduces great uncertainty as to the prevalence and distribution of respective species from the different sample types. This is especially true when considering isolation of Campylobacter spp. causing disease in man as there is no certainty that the selected isolate is that which was responsible for disease. The incorporation of antibiotics into the isolation media not only introduces the issue of species bias but perhaps more importantly exposes the Campylobacter spp. to a cocktail of antibiotics thereby providing the potential for them to 'switch on' antibiotic resistance mechanisms. It might be argued that this has always been the case for isolation of Campylobacter spp., however, we know that the antibiotic cocktails used in media over the last 10 years have changed and indeed there was a time when the filtration protocol which didn't use antibiotics was more widely used. As most reports in the literature do not state what methods were used to isolate Campylobacter spp. it is not possible to quantify any relationship between antibiotics used in the isolation media and susceptibility data. An approved method for Campylobacter susceptibility testing was not available until May 2002, all data generated prior to this date will have been generated using non-standard methods. As tremendous variability in the reproducibility data for Campylobacter spp. was observed during the development of the standard agar dilution susceptibility method, data generated with disk diffusion and broth microdilution methods must be considered with caution. It has been shown that, compared with the conventional agar dilution method, the E-test tends to give rise to lower minimal inhibitory concentrations (MICs) for sensitive strains and higher MICs for resistant strains. There are no recommended antibiotic breakpoint concentrations for Campylobacter spp. A breakpoint is used to separate sensitive from resistant strains of bacteria and is thus crucial to any discussion of antibiotic resistance. This discussion is further complicated by introduction of the terms microbiological and clinical breakpoints. While a microbiological breakpoint can be a useful parameter with regard to identifying resistance factors it cannot on its own be used to predict whether that bacteria will respond to treatment from an appropriate antibiotic. Predicting clinical response is a function of the clinical breakpoint which considers the pharmacokinetic profile of the antimicrobial compound, i.e. the concentration of the antimicrobial compound in the body and the MIC. The National Committee for Clinical Laboratory Standards (NCCLS) uses microbiological, pharmacokinetic and clinical data to establish breakpoints, without c and clinical data to establish breakpoints, without such considerations it is not possible to consider what is truly clinically sensitive and resistant. There are no reported studies that have systematically determined appropriate breakpoints for Campylobacter, there are data however, which relate MICs to clinical outcome. It is without dispute that microbiological resistance in Campylobacter spp. occurs as a result of mutation in the gyrA gene with single point mutations most frequently causing a four- to eightfold shift in the MIC. What is also clear is that if a high enough concentration of antimicrobial relative to MIC of the infecting organism can be achieved not only will the parent organism be killed but also the 'resistant' mutant. Considering the above and the concentrations of ciprofloxacin achieved in the gastro-intestinal tract it is not surprising that clinical cure can be demonstrated for organisms with an MIC of 32 microg ml(-1).     

The ζ toxin induces a set of protective responses and dormancy

The ζε module consists of a labile antitoxin protein, ε, which in dimer form (ε(2)) interferes with the action of the long-living monomeric ζ phosphotransferase toxin through protein complex formation. Toxin ζ, which inhibits cell wall biosynthesis and may be bactericide in nature, at or near physiological concentrations induces reversible cessation of Bacillus subtilis proliferation (protective dormancy) by targeting essential metabolic functions followed by propidium iodide (PI) staining in a fraction (20-30%) of the population and selects a subpopulation of cells that exhibit non-inheritable tolerance (1-5×10(-5)). Early after induction ζ toxin alters the expression of ～78 genes, with the up-regulation of relA among them. RelA contributes to enforce toxin-induced dormancy. At later times, free active ζ decreases synthesis of macromolecules and releases intracellular K(+). We propose that ζ toxin induces reversible protective dormancy and permeation to PI, and expression of ε(2) antitoxin reverses these effects. At later times, toxin expression is followed by death of a small fraction (～10%) of PI stained cells that exited earlier or did not enter into the dormant state. Recovery from stress leads to de novo synthesis of ε(2) antitoxin, which blocks ATP binding by ζ toxin, thereby inhibiting its phosphotransferase activity.     

Do fever and anapyrexia exist? Analysis of set point-based definitions

Fever and anapyrexia are the most studied thermoregulatory responses. They are defined as a body temperature (T(b)) increase and decrease, respectively, occurring because of a shift in the set point (SP) and characterized by active defense of the new T(b). Although models of T(b) control with a single SP (whether obvious or hidden) have been criticized, the SP-based definitions have remained unchallenged. In this article, the SP-based definitions of fever and anapyrexia were subjected to two tests. In test 1, they were compared with experimental data on changes in thresholds for activation of different thermoeffectors. Changes in thresholds were found compatible with an SP increase in some (but not all) cases of fever. In all cases of what is called anapyrexia, its mechanism (dissociation of thresholds of different effectors) was found incompatible with a decrease in a single SP. In test 2, experimental data on the dependence of T(b) on ambient temperature (T(a)) were analyzed. It was found that the febrile level of T(b) is defended in some (but not all) cases. However, strong dependence on T(a) was found in all cases of anapyrexia, which agrees with threshold dissociation but not with a decrease of the SP. It is concluded that fever (as defined) has only limited experimental support, whereas anapyrexia (as defined) does not exist. Two solutions are offered. A palliative is to accept that SP-based terms (anapyrexia, cryexia, regulated hypothermia, and such) are inadequate and should be abandoned. A radical solution is to transform all definitions based on comparing T(b) with the SP into definitions based on balancing active and passive processes of T(b) control.     

How do pollinator visitation rate and seed set relate to species’ floral traits and community context?

Differences among plant species in visitation rate and seed set within a community may be explained both by the species’ floral traits and the community context. Additionally, the importance of species’ floral traits vs. community context on visitation rate and seed set may vary among communities. In communities where the pollinator-to-flower ratio is low, floral traits may be more important than community context, as pollinators may have the opportunity to be choosier when visiting plant species. In this study we investigated whether species’ floral traits (flower shape, size and number, and flowering duration) and community context (conspecific and heterospecific flower density, and pollinator abundance) could explain among-species variation in visitation rate and seed set. For this, we used data on 47 plant species from two Norwegian plant communities differing in pollinator-to-flower ratio. Differences among species in visitation rate and seed set within a community could be explained by similar variables as those explaining visitation rate and seed set within species. As expected, we found floral traits to be more important than community context in the community with a lower pollinator-to-flower ratio; whereas in the community with a higher pollinator-to-flower ratio, community context played a bigger role. Our study gives significant insights into the relative importance of floral traits on species’ visitation rate and seed set, and contributes to our understanding of the role of the community context on the fitness of plant species.     

Bateman’s principle and plant reproduction: The role of pollen limitation in fruit and seed set

Bateman’s principle states that male fitness is usually limited by the number of matings achieved, while female fitness is usually limited by the resources available for reproduction. When applied to flowering plants this principle leads to the expectation that pollen limitation of fruit and seed set will be uncommon. However, if male searching for mates (including pollen dissemination via external agents) is not sufficiently successful, then the reproductive success of both sexes (or both sex functions in hermaphroditic plants) will be limited by number of matings rather than by resources, and Bateman’s principle cannot be expected to apply. Limitation of female success due to inadequate pollen receipt appears to be a common phenomenon in plants. Using published data on 258 species in which fecundity was reported for natural pollination and hand pollination with outcross pollen, I found significant pollen limitation at some times or in some sites in 159 of the 258 species (62%). When experiments were performed multiple times within a growing season, or in multiple sites or years, the statistical significance of pollen limitation commonly varied among times, sites or years, indicating that the pollination environment is not constant. There is some indication that, across species, supplemental pollen leads to increased fruit set more often than increased seed set within fruits, pointing to the importance of gamete packaging strategies in plant reproduction. Species that are highly self-incompatible obtain a greater benefit relative to natural pollination from artificial application of excess outcross pollen than do self-compatible species. This suggests that inadequate pollen receipt is a primary cause of low fecundity rates in perennial plants, which are often self-incompatible. Because flowering plants often allocate considerable resources to pollinator attraction, both export and receipt of pollen could be limited primarily by resource investment in floral advertisement and rewards. But whatever investment is made is attraction, pollinator behavioral stochasticity usually produces wide variation among flowers in reproductive success through both male and female functions. In such circumstances the optimal deployment of resources among megaspores, microspores, and pollinator attraction may often require more flowers or more ovules per flower than will usually be fertilized, in order to benefit from chance fluctuations that bring in large number of pollen grains. Maximizing seed set for the entire plant in a stochastic pollination environment might thus entail a packaging strategy for flower number or ovule number per flower that makes pollen limitation of fruit or seed set likely. Pollen availability may limit female success in individual flowers, entire plants (in a season or over a lifetime), or populations. The appropriate level must be distinguished depending on the nature of the question being addressed.     

Are seed set and speciation rates always low among species that resprout after fire, and why?

A general dichotomy in response to catching alight during fire is for perennial plants to die (nonsprouters, N) or to regrow via dormant buds (resprouters, R). Contrasting effects on other life-history traits, especially those relating to sexual reproduction, can be expected. We hypothesized that fecundity should be lower in R. Our meta-analysis of 33 case studies of co-occurring generic pairs of N and R showed that viable seed and fruit set relative to inflorescence, flower and ovule production were lower for R than N in 30 cases. Three mechanisms have been invoked to explain these trends: resource competition between vegetative and reproductive growth, an outbreeding (R)/inbreeding (N) dichotomy, and higher genetic load among R due to their accumulation of deleterious somatic mutations over many fire cycles. Though poorly researched, we conclude that the high genetic load of R in association with strong self-incompatibility (xenogamy) can best explain the dichotomy in lifeform-fecundity as well as the exceptions. Over the long-term, we suggest that marked xenogamy-longevity in association with frequent axillary branching (induced by recurrent fire, herbivory and drought) via copious stored buds within R might favour expression among their genets and ramets of beneficial somatic mutations present in their meristematic tissues. These conditions would favour ecotypic differentiation and speciation among R that has contributed, along with N, to the exceptional species richness of several fire-prone mediterranean regions.     

Pollination and seed set of an obligatory outcrossing plant in an urban–peri-urban gradient

Urban land use strongly affects pollinators and plant pollination due to fragmentation and isolation of natural plant populations. On the other hand, urban land use can potentially be beneficial to pollinators through the presence of urban gardens and parks which are usually designed to ensure abundant flowering. However, little is known about the effects of urban land use on bees and the pollination services they provide. In an urban–peri-urban gradient around Leuven, Belgium we studied flower visitation rates to, and seed set of Trifolium repens (white clover) in public lawns. T. repens is an obligatory outcrossing plant and is therefore sensitive to reductions in pollinator services. We related our results to both local and regional variables using Boosted Regression Trees. The two variables that best explained the variability in visitation rates and seed set were the amount of green areas (gardens, parks, grasslands) in the surroundings and the abundance of T. repens in the lawns. Surprisingly, an increasing amount of green areas in the surroundings had a negative effect on both flower visitation rates to, and seed set of T. repens. Flower visitation rates by bumblebees responded positively to urban land use resulting in higher visitation rates and increased seed set in the more urban sites. This may point either to increased abundance of bumblebees in more urban sites or to a concentration effect of bumblebees in our urban study sites due to a lack of alternative forage resources. Responses will likely differ for other bee and plant species, but this shows that at least for T. repens, pollination is not compromised by urban land use.     

Expanding the set of rhodococcal Baeyer–Villiger monooxygenases by high-throughput cloning, expression and substrate screening

To expand the available set of Baeyer-Villiger monooxygenases (BVMOs), we have created expression constructs for producing 22 Type I BVMOs that are present in the genome of Rhodococcus jostii RHA1. Each BVMO has been probed with a large panel of potential substrates. Except for testing their substrate acceptance, also the enantioselectivity of some selected BVMOs was studied. The results provide insight into the biocatalytic potential of this collection of BVMOs and expand the biocatalytic repertoire known for BVMOs. This study also sheds light on the catalytic capacity of this large set of BVMOs that is present in this specific actinomycete. Furthermore, a comparative sequence analysis revealed a new BVMO-typifying sequence motif. This motif represents a useful tool for effective future genome mining efforts.     

How to narrow down chromosomal breakpoints in small and large derivative chromosomes – a new probe set

Here a new fluorescence in situ hybridization (FISH-) based probe set is presented and its possible applications are highlighted in 34 exemplary clinical cases. The so-called pericentric-ladder-FISH (PCL-FISH) probe set enables a characterization of chromosomal breakpoints especially in small supernumerary marker chromosomes (sSMC), but can also be applied successfully in large inborn or acquired derivative chromosomes. PCL-FISH was established as 24 different chromosome-specific probe sets and can be used in two- up multicolor-FISH approaches. PCL-FISH enables the determination of a chromosomal breakpoint with a resolution between 1 and ～10 megabasepairs and is based on locus-specific bacterial artificial chromosome (BAC) probes. Results obtained on 29 sSMC cases and five larger derivative chromosomes are presented and discussed. To confirm the reliability of PCL-FISH, eight of the 29 sSMC cases were studied by array-comparative genomic hybridization (aCGH); the used sSMC-specific DNA was obtained by glass-needle based microdissection and DOP-PCR-amplification. Overall, PCL-FISH leads to a better resolution than most FISH-banding approaches and is a good tool to narrow down chromosomal breakpoints.     

Predicting the structure and vibrational frequencies of ethylene using harmonic and anharmonic approaches at the Kohn–Sham complete basis set limit

In this work, regular convergence patterns of the structural, harmonic, and VPT2-calculated anharmonic vibrational parameters of ethylene towards the Kohn–Sham complete basis set (KS CBS) limit are demonstrated for the first time. The performance of the VPT2 scheme implemented using density functional theory (DFT-BLYP and DFT-B3LYP) in combination with two Pople basis sets (6-311++G** and 6-311++G(3df,2pd)), the polarization-consistent basis sets pc-n, aug-pc-n, and pcseg-n (n?=?0, 1, 2, 3, 4), and the correlation-consistent basis sets cc-pVXZ and aug-cc-pVXZ (X?=?D, T, Q, 5, 6) was tested.The BLYP-calculated harmonic frequencies were found to be markedly closer than the B3LYP-calculated harmonic frequencies to the experimentally derived values, while the calculated anharmonic frequencies consistently underestimated the observed wavenumbers. The different basis set families gave very similar estimated values for the CBS parameters. The anharmonic frequencies calculated with B3LYP/aug-pc-3 were consistently significantly higher than those obtained with the pc-3 basis set; applying the aug-pcseg-n basis set family alleviated this problem. Utilization of B3LYP/aug-pcseg-n basis sets instead of B3LYP/aug-cc-pVXZ, which is computationally less expensive, is suggested for medium-sized molecules. Harmonic BLYP/pc-2 calculations produced fairly accurate ethylene frequencies.

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Graphical Abstract In this study, the performance of the VPT2 scheme implemented using density functional theory (DFT-BLYP and DFT-B3LYP) in combination with the polarization-consistent basis sets pc-n, aug-pc-n, and pcseg-n (n?=?0, 1, 2, 3, 4), and the correlation-consistent basis sets cc-pVXZ and aug-cc-pVXZ (X?=?D, T, Q, 5, and 6) was tested. For the first time, we demonstrated regular convergence patterns of the structural, harmonic, and VPT2-calculated anharmonic vibrational parameters of ethylene towards the Kohn–Sham complete basis set (KS CBS) limit

     

gβ- and gγ-turns in proteins revisited: A new set of amino acid turn-type dependent positional preferences and potentials

The number of beta-turns in a representative set of 426 protein three-dimensional crystal structures selected from the recent Protein Data Bank has nearly doubled and the number of gamma-turns in a representative set of 320 proteins has increased over seven times since the previous analysis. Beta-turns (7153) and gamma-turns (911) extracted from these proteins were used to derive a revised set of type-dependent amino acid positional preferences and potentials. Compared with previous results, the preference for proline, methionine and tryptophan has increased and the preference for glutamine, valine, glutamic acid and alanine has decreased for beta-turns. Certain new amino acid preferences were observed for both turn types and individual amino acids showed turn-type dependent positional preferences. The rationale for new amino acid preferences are discussed in the light of hydrogen bonds and other interactions involving the turns. Where main-chain hydrogen bonds of the type NH(i + 3) --> CO(i) were not observed for some beta-turns, other main-chain hydrogen bonds or solvent interactions were observed that possibly stabilize such beta-turns. A number of unexpected isolated beta-turns with proline at i + 2 position were also observed. The NH(i + 2) --> CO(i) hydrogen bond was observed for almost all gamma-turns. Nearly 20% classic gamma-turns and 43% inverse gamma-turns are isolated turns.     

Spatial and temporal relation rule acquisition of eutrophication in Da’ning River based on rough set theory

Since the mechanisms of eutrophication are complicated and many other factors affect these mechanisms, methods such as quantitative statistics and numerical simulation, have their limitations in analyzing the spatiotemporal relations of eutrophication. The rough set theory (RST) was used to describe the spatiotemporal relations of eutrophication in Da’ning River without any of other prior knowledge. Rules of relations in time and space affecting eutrophication in the Da’ning River backwater area were extracted by taking representation of relations in time and space among eutrophication at a long river section of Da’ning River backwater area, by taking nine sets of encrypted monitoring data in 2003 as example, and by making season, area and eutrophication level as the decision attributes, respectively, to represent specific features of the eutrophication phenomenon in the Da’ning River backwater area from the points of view of time, space, and level by analysis of spatiotemporal relationship rules. This study result shows that the temporal and spatial differences between eutrophication phenomena in the long river section of the Da’ning River backwater area are significant. Eutrophication for each section is less serious in autumn, more in spring and most in summer. Eutrophication degree gradually decreases from estuary to upstream, which is in conformity with reality. The RST of eutrophication in Da’ning River may inform environmental decision-makers and assist them in making more cost-effective decisions.     

Do local conspecific density and floral display size influence fruit set via pollinator visitation in Orchis militaris?

Plant density varies naturally, from isolated plants to clumped individuals, and this can influence pollinator foraging behaviour and plant reproductive success. In addition, the effect of conspecific density on reproduction may depend on the pollination system, and deceptive species differ from rewarding ones in this regard, a high density being often associated with low fruit set in deceptive plants. In our study, we aimed to determine how local conspecific density and floral display size (i.e. number of flowers per plant) affect fruit set in a deceptive orchid (Orchis militaris) through changes in pollinator visitation. We measured fruit set in a natural population and recorded pollinator abundance and foraging behaviour within plots of different O. militaris densities. Detailed data were recorded for the most abundant potential pollinators of O. militaris, i.e. solitary bees. Floral display size was negatively correlated to fruit set in medium‐density plots, but uncorrelated in low‐ and high‐density plots. Plot density had no effect on solitary bee abundance and visitation, which may be due to low pollinator abundance within the study site. The proportion of visited flowers per inflorescence was negatively influenced by floral display size, which is in line with previous studies. In addition, solitary bees spent decreasing time in successive flowers within an inflorescence, and the time spent per flower was negatively affected by ambient temperature. Our results suggest that pollinator behaviour during visitation is poorly linked to pollen deposition and reproductive success in O. militaris.     

Spectral power of θ and α-EEG bands in preschool children with different levels of visual set plasticity

The spectral powers (SPs) of the θ and α EEG rhythms were studied at different stages of visual set in children from five to seven years of age. Children with a plastic set had a greater α band SP than those with a rigid set. At the set formation stage, children with a rigid set displayed an increase in the SP of the θ band, which is a manifestation of an “immature” activation reaction. Children with a plastic set exhibited an increase in the α band SP in the occipital lobes of both hemispheres. The dynamics of the SP of the EEG rhythms differed in children younger and older than six years. At the set formation stage, children from five to six years of age exhibited the above-mentioned “immature” activation reaction, while those from six to seven years of age showed an increase in the α band SP in the occipital lobes. At the set actualization stage, an increase in the α band SP was observed in the right caudal areas, while the set extinction stage was marked by a bilateral depression of the α band in the frontal lobes. The importance of the involvement of specific cortical areas in visual perception and the formation of a plastic set is discussed.     

set1／set2毒力基因分型在F2a菌痢暴发流行病学调查中的意义

目的将set1/set2 毒力基因分型用于F2a 志贺氏菌痢暴发中的同源性分析,评价其在菌痢流行病学调查中的意义。方法在现场流行病学调查的基础上,用聚合酶链分析(PCR) 方法检测43 株F2a 志贺氏菌的set1/set2 毒力基因,进行基因分型和同源性鉴定。结果43 株F2a 菌株分为3 种基因型,即1 株set1( - )/set2( ) ;3 株set1( )/set2( - ) ;39 株set1( )/set2( ) 。结论set1/set2 基因分型对F2a 菌痢暴发流行中的同源性鉴定具有重要意义。     

Dioxovanadium(V) and μ-oxo bis[oxovanadium(V)] complexes containing thiosemicarbazone based ONS donor set and their antiamoebic activity

Neutral dioxovanadium (V) complexes [VO₂(HL)] (H₂L = I: 1, H₂L = II: 2 and H₂L = III: 3; H₂L are the thiosemicarbazones H₂pydx-tsc (I), H₂pydx-chtsc (II) and H₂pydx-clbtsc (III); pydx = pyridoxal, tsc = thiosemicarbazide, chtsc = N₄-cyclohexylthiosemicarbazide, clbtsc = N₄-(2-chloro)benzylthiosemicarbazide) have been isolated and characterised on the basis of elemental and electrochemical analyses, spectroscopic (IR, UV-Vis, ¹H and ⁵¹V NMR) data, thermogravimetric studies and reactivity patterns. These complexes are stable in solution at ambient temperature but heating of the methanolic solutions yields the μ-oxo binuclear complexes [(VOL)₂μ-O] (H₂L = I: 4, H₂L = II: 5, H₂L = III: 6). Treatments of dioxo species with H₂O₂ yield oxoperoxo species, the formations of which have been established spectrophotometrically. Similarly, the formations of oxohydroxo species, an intermediate proposed during the catalytic action of haloperoxidases, have also been established in solution by treating 1, 2 and 3 with a methanolic solution of HCl. The antiamoebic activities were carried out to ascertain the effectiveness of dioxovanadium(V) and μ-oxobis(oxovanadium(V)) complexes in comparison to their corresponding thiosemicarbazones. These complexes possess noteworthy potencies against HM1:1MSS strain of Entamoeba histolytica. Complexes 2, 3, 5 and 6 showed less IC₅₀ values than metronidazole, indicating that these metal thiosemicarbazones may be the lead molecules to inhibit the growth of E. histolytica. Within the series, complex 5 showed the most promising amoebicidal activity (IC₅₀ = 0.5 μM versus IC₅₀ = 1.8 of metronidazole).     

Interaction-induced electric (hyper)polarizability in the dihydrogen–neon pair: basis set and electron correlation effects

We investigated the interaction (hyper)polarizability of neon–dihydrogen pairs by performing high-level ab initio calculations with atom/molecule-specific, purpose-oriented Gaussian basis sets. We obtained interaction-induced electric properties at the SCF, MP2, and CCSD levels of theory. At the CCSD level, for the T-shaped configuration, around the respective potential minimum of 6.437 a₀, the interaction-induced mean first hyperpolarizability varies for 5?<? R/a₀?<?10 as

$$ \left[{\overline{\beta}}_{\mathrm{int}}(R)\hbox{-} {\overline{\beta}}_{\mathrm{int}}\left({R}_{\mathrm{e}}\right)\right]/{e}^3{a_0}^3{E_{\mathrm{h}}}^{-2}=-0.91\left(R\hbox{-} {R}_{\mathrm{e}}\right)+0.50{\left(R\hbox{-} {R}_{\mathrm{e}}\right)}^2\hbox{--} 0.13{\left(R\hbox{-} {R}_{\mathrm{e}}\right)}^3+0.01{\left(R\hbox{-} {R}_{\mathrm{e}}\right)}^4. $$

Again, at the CCSD level, but for the L-shaped configuration around the respective potential minimum of 6.572 a₀, this property varies for 5?<? R/a₀?<?10 as

$$ \left[{\overline{\beta}}_{\mathrm{int}}(R)\hbox{-} {\overline{\beta}}_{\mathrm{int}}\left({R}_{\mathrm{e}}\right)\right]/{e}^3{a_0}^3{E_{\mathrm{h}}}^{-2}=-1.33\left(R\hbox{-} {R}_{\mathrm{e}}\right)+0.75{\left(R\hbox{-} {R}_{\mathrm{e}}\right)}^2-0.20{\left(R\hbox{-} {R}_{\mathrm{e}}\right)}^3+0.02{\left(R\hbox{-} {R}_{\mathrm{e}}\right)}^4. $$

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Graphical Abstract Interaction-induced mean dipole polarizability (\( \overline{a} \)) for the T-shaped configuration of H₂–Ne calculated at the SCF, MP2, and CCSD levels of theory