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PubMed2004

Development and large scale benchmark testing of the PROSPECTOR_3 threading algorithm.

This article describes the PROSPECTOR_3 threading algorithm, which combines various scoring functions designed to match structurally related target/template pairs. Each variant described was found to have a Z-score above which most identified templates have good structural (threading) alignments, Z(struct) (Z(good)). 'Easy' targets with accurate threading alignments are identified as single templates with Z > Z(good) or two templates, each with Z > Z(struct), having a good consensus structure in mutually aligned regions. 'Medium' targets have a pair of templates lacking a consensus structure, or a single template for which Z(struct) < Z < Z(good). PROSPECTOR_3 was applied to a comprehensive Protein Data Bank (PDB) benchmark composed of 1491 single domain proteins, 41-200 residues long and no more than 30% identical to any threading template. Of the proteins, 878 were found to be easy targets, with 761 having a root mean square deviation (RMSD) from native of less than 6.5 A. The average contact prediction accuracy was 46%, and on average 17.6 residue continuous fragments were predicted with RMSD values of 2.0 A. There were 606 medium targets identified, 87% (31%) of which had good structural (threading) alignments. On average, 9.1 residue, continuous fragments with RMSD of 2.5 A were predicted. Combining easy and medium sets, 63% (91%) of the targets had good threading (structural) alignments compared to native; the average target/template sequence identity was 22%. Only nine targets lacked matched templates. Moreover, PROSPECTOR_3 consistently outperforms PSIBLAST. Similar results were predicted for open reading frames (ORFS) < or =200 residues in the M. genitalium, E. coli and S. cerevisiae genomes. Thus, progress has been made in identification of weakly homologous/analogous proteins, with very high alignment coverage, both in a comprehensive PDB benchmark as well as in genomes.

Algorithms↗
PubMed1994

Dose-response assessment for developmental toxicity. II. Comparison of generic benchmark dose estimates with no observed adverse effect levels.

Developmental toxicity risk assessment currently relies on the estimation of reference doses (RfDDTS) of reference concentrations (RfCDTS) based on the use of no observed adverse effect levels (NOAELS) divided by uncertainty factors (UFs). The benchmark dose (BMD) has been proposed as an alternative basis for reference value calculations. A large database of 246 developmental toxicity experiments representing 1825 endpoints related to dead implants or malformed fetuses has been compiled for use in evaluating alternative approaches to developmental toxicity risk assessment. Using this database we have compared two approaches for BMD estimation with each other and with corresponding statistically derived NOAELS. Comparisons have been based on proportion of affected litters (litters with one or more affected offspring, a quantal response variable) and on the proportion of affected offspring within each litter (a continuous response variable). A quantal Weibull model was used to calculate generic BMDs for the quantal response variable (QBMDs) and a continuous power model was used to calculate generic BMDs for the continuous response variable (CBMDs) at three levels of additional risk (10, 5, and 1%). CBMD05s (continuous benchmark doses for 5% risk) and CNOAELs (statistically derived NOAELs based on the continuous response variable) were similar, with over 98% of the data subsets having CBMD05 and CNOAEL values that differed by less than an order of magnitude. In contrast, QNOAELs tended to be greater than corresponding QBMD10s. The observed conservatism of the QBMD values relative to the corresponding CBMD values was attributed to two factors, lower maximum likelihood estimates for the quantal model and wider confidence intervals around the maximum likelihood estimates, compared to the continuous model.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Estimation of a chromium inhalation reference concentration using the benchmark dose method: a case study.

The benchmark dose (BD) method has been proposed as an alternative to the NOAEL/UF method for setting reference levels. The BD is the 95% lower confidence limit on a dose corresponding to a 10% increase (or relative change) in an adverse effect. A case study exploring the suitability of the current Cr(III) and Cr(VI) inhalation toxicity data bases to the BD approach is presented. Because chromic acid mists, typical of many occupational Cr(VI) exposures, present a toxicological profile different from that of Cr(VI) particulates, representative of environmental exposures, Cr(VI) particulate data were evaluated separately from Cr(VI) acidic mist data. The current Cr(III) and Cr(VI) acidic mist data bases proved inadequate for BD analysis due to data and/or study quality limitations. Benchmark reference concentrations (RfCs) for particulate Cr(VI) ranging from 0.34 microgram/m3 (for lactate dehydrogenase (LDH) in bronchoalveolar lavage fluid (BALF)) to 1.4 micrograms/m3 (for increased lung weights) are derived from data taken from U. Glaser et al. (Arch. Toxicol. 57, 250-256, 1985) and U. Glaser et al. (Environmental Hygiene II, Springer-Verlag, Berlin/New York, 1990). A Cr(VI) particulate RfC of 0.34 microgram/m3 based upon LDH in BALF as the critical effect is proposed. This value may be viewed as conservative since it represents the 95% lower confidence limit on the dose associated with a 10% increase in response for a sensitive endpoint and has appropriate dosimetric adjustments and uncertainty factors incorporated.

Administration, Inhalation↗
PubMed1999

The use of benchmark dose methodology with acute inhalation lethality data.

Benchmark dose methodology has been proposed as a refinement to the no observed adverse effect level (NOAEL) methods currently used for health risk assessments. We compared log-normal probit and quantal Weibull benchmark concentration (BMC) estimates using 1, 5, and 10% response incidences with inhalation toxicity NOAELs and LOAELs from 120 acute lethality data sets. These studies yielded relatively steep dose-response slopes, which in turn influenced the suitability of selecting response incidences. The mean magnitude of difference between the 95% lower confidence limits (LCLs) for 1, 5, or 10% BMCs and corresponding NOAELs was less than twofold using the probit model and less than fourfold using the Weibull model. BMC estimates at the 10% response exceeded the observed LOAEL in some cases. Maximum likelihood estimates for doses with 1, 5, or 10% responses frequently exceeded LOAELs. The probit model repeatedly gave a better fit for the data compared with the Weibull model, resulting in improved goodness of fit tests and reduced 95% confidence intervals. The 95% LCL appears to be necessary at the 1, 5, or 10% response levels in order to safely estimate a concentration below that resulting in a LOAEL.

Aerosols↗
PubMed2006

Benchmark dose of working hours in relation to subjective fatigue symptoms in Japanese male workers.

PURPOSE: We used a multiple logistic regression model to calculate benchmark doses (BMDs) and their 95% lower confidence bound (BMDL) of working hours for subjective fatigue symptoms. METHODS: A self-administered questionnaire survey was conducted in 3069 male daytime workers between the ages of 18 and 60 years who worked in a Japanese steel company. Dependent variables were positive findings for eight properties by using the Cumulative Fatigue Symptoms Index (CFSI): decreased vitality, general fatigue, physical disorders, irritability, decreased willingness to work, anxiety, depressive feelings, and chronic tiredness. Independent variables were daily working hours, age, lifestyle factors, working conditions (type of work and number of holidays), marital status, and living arrangements. Using significant parameters for working hours and those for other covariates, BMD/BMDL of working hours was calculated for the corresponding property of the CFSI. Additionally, benchmark response (BMR) was set at 5% or 10%. RESULTS: The BMD/BMDL of working hours per day with a BMR of 5% were 11.8/10.8 (irritability), 11.4/10.2 (anxiety), and 11.2/10.6 (chronic tiredness), and those with a BMR of 10% were 14.2/12.6 (irritability), 14.2/12.1 (anxiety), and 13.1/12.2 (chronic tiredness). CONCLUSIONS: These results strongly suggest that special attention should be given to workers whose working hours exceed these BMD/BMDL values.

Adolescent↗
PubMed2005

A procedure for benchmarking laboratory exposures with 1 A GeV iron ions.

A new version of the HZETRN code capable of simulating HZE ions with either laboratory or space boundary conditions is under development. The computational model consists of combinations of physical perturbation expansions based on the scales of atomic interaction, multiple scattering, and nuclear reactive processes with use of asymptotic/Neumann expansions with non-perturbative corrections. The code contains energy loss with straggling, nuclear attenuation, nuclear fragmentation with energy dispersion and downshifts, and off-axis dispersion with multiple scattering under preparation. The present benchmark is for a broad directed beam for 1 A GeV iron ion beams with 2 A MeV width and four targets of polyethylene, polymethyl metachrylate, aluminum, and lead of varying thickness from 5 to 30 g/cm2. The benchmark quantities will be dose, track averaged LET, dose averaged LET, fraction of iron ion remaining, and fragment energy spectra after 23 g/cm2 of polymethyl metachrylate.

Aluminum↗
PubMed2006

BIOREL: the benchmark resource to estimate the relevance of the gene networks.

The progress of high-throughput methodologies in functional genomics has lead to the development of statistical procedures to infer gene networks from various types of high-throughput data. However, due to the lack of common standards, the biological significance of the results of the different studies is hard to compare. To overcome this problem we propose a benchmark procedure and have developed a web resource (BIOREL), which is useful for estimating the biological relevance of any genetic network by integrating different sources of biological information. The associations of each gene from the network are classified as biologically relevant or not. The proportion of genes in the network classified as "relevant" is used as the overall network relevance score. Employing synthetic data we demonstrated that such a score ranks the networks fairly in respect to the relevance level. Using BIOREL as the benchmark resource we compared the quality of experimental and theoretically predicted protein interaction data.

Computational Biology↗
PubMed2005

Comparing outcomes of voice therapy: a benchmarking study using the therapy outcome measure.

The quality cycle requires clinicians to assess the outcomes of interventions. Benchmarking is an approach that has been advocated to compare current performance across different services to identify commonalities and significant differences. This article gives the results of a study of outcomes in speech and language therapy (SLT) using the therapy outcome measure (TOM) for patients with voice disorder (dysphonia) comparing outcomes of seven separate speech and language therapy services. The study aimed to identify the similarities and differences in outcomes of care provided by different services. Two hundred and forty patients with dysphonia (age range 3-87.5 years, average 51.9 years) were treated. The results indicated that although there was no significant difference in the profile of the severity of symptomology of patients referred to speech and language therapy in different geographical areas, there was a significant difference in the treatment outcomes across the services and in the stated reason for discharge from treatment. Nevertheless, most patients with dysphonia had a good outcome and this was associated with completion of the course of treatment. There were significant differences in the number of treatment contacts provided by the different services and in the duration (between admission and discharge) of treatment across the services. Benchmarking can provide useful information through use of routinely collected clinical data.

Adolescent↗
PubMed1997

Event status of the Starr-Edwards aortic valve to 20 years: a benchmark for comparison.

BACKGROUND: Considerable effort and expense has been invested in the evolutionary development of cardiac valvular prostheses with the goal of reducing or minimizing specific events related to these prostheses. It is important to measure any improvement achieved with such development by comparison against a historic standard. The Starr-Edwards caged-ball prosthesis model 1260 has been used for 30 years as the predominant or sole model of its kind for aortic valve replacement. This historic opportunity provides a benchmark for subsequent improvement and comparison of current prostheses. METHODS: Between 1969 and 1991, 1,100 patients (median age, 57 years; 838 men and 194 women) underwent aortic valve replacement with or without coronary artery bypass grafting (aortic valve replacement, 964; aortic valve replacement plus coronary artery bypass grafting, 136) with the 1260 Starr-Edwards caged-ball prosthesis. RESULTS: Operative mortality was 6.2% (68 patients). Univariate patient characteristics predictive of early mortality were female sex (p = 0.003), age (> 56 years; p = 0.002), recent operative interval (1985 to 1991 versus 1969 to 1976 or 1977 to 1984; p = 0.002), presence of atrial fibrillation (p = 0.001), and small valve size (7A to 8A = 19 to 21 mm; p < 0.001). Follow-up extended to 11,293 patient-years (mean, 24.8 years) and was 96.9% complete. Survival at 5, 10, 15, and 20 years for all patients including operative mortality was 76.6%, 59.6%, 44.9%, and 31.2%, respectively. Operative variables predictive of poor late survival were advanced New York Heart Association class (III or IV); (p = 0.0001), older age (> 56 years; p = 0.0001), and lower (< 0.56) ejection fraction (p = 0.0001). Freedom from thromboemboli and anticoagulant-related bleeding at 5 years was 90.8% and 98.7%, respectively. Univariate model for greater risk of late thromboemboli identified female sex (p = 0.04), older age (> 56 years; p = 0.0002), and New York Heart Association class III or IV (p = 0.0058), as risk factors. Multivariate analysis for thromboemboli demonstrated older age (p = 0.0007) and New York Heart Association class III or IV (p = 0.0041) as significant. Alternatively, univariate analysis for late bleeding found only the most recent operative interval (p = 0.009) as significant, and the rarity of events prevented a multivariate query. There were no valve failures. CONCLUSIONS: The late results of survival and freedom from late anticoagulant-related bleeding or thromboemboli are excellent, especially in larger (9A and above) sizes, and with the long implant record comparable with more recent prostheses, the Starr-Edwards valve provides an excellent, safe, and durable alternative in the aortic position and provides a benchmark against which to compare other prostheses.

Anticoagulants↗
PubMed2000

Benchmark dose calculations of methylmercury-associated neurobehavioural deficits.

Prenatal methylmercury exposure is associated with neuropsychological deficits in Faroese children at age 7 years. Lower confidence bounds of benchmark doses (BMDLs) have now been calculated. With the cord-blood mercury concentration as the dose parameter, a logarithmic dose-response model tended to show a better fit than a linear dose model for the attention, language and verbal memory tests. The lowest BMDLs averaged approximately 5 microgram/l cord blood, which corresponds to a maternal hair concentration of approximately 1 microgram/g. However, most BMDLs for hair mercury concentrations were higher. Thus, the results of the benchmark calculations depend on the assumed dose-response model.

Biomarkers↗
PubMedDate not supplied

Benchmarking the MCNP code for Monte Carlo modelling of an in vivo neutron activation analysis system.

The Monte Carlo computer code MCNP (version 4A) has been used to develop a personal computer-based model of the Swansea in vivo neutron activation analysis (IVNAA) system. The model included specification of the neutron source (252Cf), collimators, reflectors and shielding. The MCNP model was 'benchmarked' against fast neutron and thermal neutron fluence data obtained experimentally from the IVNAA system. The Swansea system allows two irradiation geometries using 'short' and 'long' collimators, which provide alternative dose rates for IVNAA. The data presented here relate to the short collimator, although results of similar accuracy were obtained using the long collimator. The fast neutron fluence was measured in air at a series of depths inside the collimator. The measurements agreed with the MCNP simulation within the statistical uncertainty (5-10%) of the calculations. The thermal neutron fluence was measured and calculated inside the cuboidal water phantom. The depth of maximum thermal fluence was 3.2 cm (measured) and 3.0 cm (calculated). The width of the 50% thermal fluence level across the phantom at its mid-depth was found to be the same by both MCNP and experiment. This benchmarking exercise has given us a high degree of confidence in MCNP as a tool for the design of IVNAA systems.

Body Composition↗
PubMed1994

Benchmarking in health care: turning challenges into success.

BACKGROUND: Since 1990, more than 120 partner hospitals have participated in 15 projects using a collaborative benchmarking approach developed by SunHealth Alliance. EXAMPLE: Medical records project. Twenty hospitals focused on activities that could reduce accounts receivable days in medical records for Medicare inpatients. Thirty-five key practices, as identified by correspondence and site visits for four benchmark hospitals, were reviewed with all 20 hospitals. EXAMPLE: Pneumonia project. Four hospitals focused on reducing the length of stay and mortality rates for pneumonia (DRG [diagnosis-related group] 89) patients. Each hospital formed internal task forces, who reviewed comparative data, analyzed their hospitals' internal care processes, determined opportunities for improvement, and chose best practices for implementation-including standardizing the sputum-collection process and developing a clinical path. Meeting the challenge. Hospitals should strive for innovation, seek new goals of excellence, and share their successes with other hospitals.

Data Collection↗
PubMed1996

Benchmarking patient satisfaction at academic health centers.

BACKGROUND: In 1991 the University HealthSystem Consortium (UHC), an alliance of 70 academic health centers, began its patient satisfaction benchmarking project. The survey, adapted from the Picker Institute survey, was pilot tested in 1992 and has been in use since 1993. Each year the project's steering committee refines the survey on the basis of member needs and survey item performance. KEY FINDINGS: Findings have shown that the survey can document the effects of specific quality improvement efforts, that patients from different medical services report different levels of satisfaction with their care, and that physician and nursing care have had the greatest impact on overall satisfaction. USING THE RESULTS: Each participating organization receives concise narrative reports of the survey results, with priorities for improvement efforts clearly highlighted. A five-to six-page Executive Summary provides the organization's executive team with a quick overview of the results, as well as a summary of the areas where quality improvements are most needed. A longer Managers' Report provides a more detailed analysis of the findings for quality managers and department heads. Sections for each major area of care can be copied and distributed as "stand alone" reports to the appropriate decision makers. For example, the section on nursing care can be distributed to the chief nursing officer and nurse managers. For each key aspect of the patient's experience, best practices for maintaining patient satisfaction are identified from across the hospitals and compiled into a catalogue. LESSONS LEARNED: The UHC patient satisfaction benchmarking program has created ongoing communication among the participating hospitals, whose staff members have been willing to share problems encountered and possible solutions.

Academic Medical Centers↗
PubMed1996

Improving health care, Part 3: Clinical benchmarking for best patient care.

BACKGROUND: Benchmarking, which shows that a much better way of doing something may be possible, stimulates local interest in changing and in making changes previously thought not possible. A PLANNING WORKSHEET: The Worksheet has five basic steps: Identify measures, determine resources needed to find the "best of the best," design a data collection method and gather data, measure the best against own performance to determine gap, and identify the best practices producing best-in-class results. CASE EXAMPLE--BOWEL SURGERY: The Accelerating Clinical Improvement Bowel Surgery Team at Dartmouth-Hitchcock Medical Center (Lebanon, NH) was formed in November 1994 to improve the care of patients with diagnosis-related group (DRG) 148 or 149. Consulting two large, administrative databases and the medical literature, the team found that a substantial gap existed between the bowel surgery delivery process and the best results, as far as they were known, among comparable organizations. After flowcharting the delivery process, the team identified the high-leverage steps: same-day services, general surgery clinic, and routine care. The team then planned three successive PDCA (plan-do-check-act) cycles: utilization of same-day services for all elective surgery patients, establishment of a standardized preoperative bowel preparation, and utilization of pre- and postoperative routine care orders. These improvement cycles resulted in a reduction in length of stay from 9.66 to 8.29 days. Implementation of a critical pathway resulted in a further reduction to 5.04 days. CONCLUSION: Benchmarking can play an integral role in clinical improvement work and can stimulate wise clinical changes and promote measured improvements in quality and value.

Academic Medical Centers↗
PubMed2006

Location of spectroscopic probes in self-aggregating assemblies. I. The case for 5-doxylstearic acid methyl ester serving as a benchmark spectroscopic probe to study micelles.

A strategy to locate spectroscopic probes in micelles is presented which involves establishing a "benchmark" probe, i.e., one whose position is well-known and against which other probe positions may be established. Theoretically calculated values of the fraction of the micelle polar shell occupied by water, H(shell), are compared with experimental values measured with the spin probe 5-doxylstearic acid methyl ester (5DSE) for a series of sodium n-alkyl sulfate micelles as functions of both the aggregation numbers and the alkyl chain length. The theoretical values involve one adjustable parameter that may be taken to be the volume in the polar shell inaccessible to water, V(dry). Under the hypothesis that the thickness of the polar shell (5 Angstroms) remains constant as either the aggregation number or the chain length is varied, we find excellent agreement between the theoretical predictions and the experimental results, using the same value of V(dry) for chain lengths 8-12 and for aggregation numbers varying from approximately 38 to 130. We argue that these are compelling reasons that 5DSE follows the zero-order model (ZOM) of probe location. The ZOM applies to any probe that rapidly diffuses within the confines of the micelle polar shell and nowhere else. Thus, 5DSE can serve as a benchmark in the sodium alkyl sulfate micelles. As a further check, results are also presented for ammonium dodecyl sulfate micelles, where 5DSE is also found to follow the ZOM, i.e, no further adjustable parameters are needed to pass from the sodium alkyl sulfate micelles to ammonium dodecyl sulfate micelles. In contrast, results are also presented for a similar spin probe 16-doxylstearic acid methyl ester (16DSE) that is found not to adhere to the ZOM in any of the micelles. A simple first-order correction to the ZOM in which 16DSE is displaced slightly from the polar shell is shown to account for the results well. The necessary displacements, which range from about 0.7 Angstroms outside the polar shell to 1.3 Angstroms inside, are not correlated with either chain lengths or aggregation numbers; however, they correlate rather well with H(shell). Calibrations of 6-, 7-, 10-, and 12DSE spin probes are presented in the Appendix, making them available to measure microviscosities and effective water concentrations.

Alkanesulfonates↗
PubMed2004

Risk assessment on renal dysfunction caused by co-exposure to arsenic and cadmium using benchmark dose calculation in a Chinese population.

Arsenic and cadmium are important inorganic toxicants in the environment. Humans certainly have the potential to be exposed to the mixtures of arsenic and cadmium, but the toxicological interactions of these inorganic mixtures are poorly defined. A general population co-exposed to arsenic and cadmium, was selected in China. The total number of participants was 245, made up of 122 in the arsenic-cadmium polluted area, 123 in the non polluted area. Urinary arsenic (UAs) and cadmium (UCd) were determined by atomic absorption spectrometry as exposure biomarkers and beta2-microglobulin (Ubeta2MG), albumin (UALB), N-acetyl-beta2-glucosaminidase (UNAG) in urine were determined as effect biomarkers. The benchmark dose (BMD) and the lower confidence limit on the benchmark dose (LBMD) were calculated to estimate the critical concentration of UAs and UCd. UAs and UCd concentrations in the polluted area were significantly higher than those in the non polluted area (P < 0.01). The levels of Ubeta2MG, UALB and UNAG in the polluted area were significantly higher than those in the non polluted area (P < 0.01). The BMD/LBMD of UAs and UCd for a 10% level of risk above the background level were estimated as 121.91/102.11 microg/g creatinine and 1.05/0.88 microg/g creatinine. It was suggested that the lower confidence limit of population critical concentration of UAs and UCd for renal dysfunction for 10% excess risk level above the background, which is obtained from LBMD, may need to be kept below 102 and 0.88 microg/g creatinine in order to prevent renal damage in general population co-exposed to arsenic and cadmium. It is indicated that combined effect of arsenic and cadmium were additive effect and/or synergistic effect, and cadmium may potentiate arsenic nephrotoxicity during the long-term and co-exposure to arsenic and cadmium in humans.

Acetylglucosaminidase↗
PubMed2004

Ligand intramolecular motions in ligand-protein interaction: ALPHA, a novel dynamic descriptor and a QSAR study with extended steroid benchmark dataset.

The role of intramolecular motions in ligand-macromolecule interactions has been explored by developing and validating ALPHA, a novel QSAR (quantitative structure-activity relationship) descriptor. It is based on the spectral exponents (alpha), which measure the degree of 1/f alpha noise of coordinate fluctuations in molecular dynamics (MD) simulations. ALPHA is the first truly 'dynamic' QSAR descriptor, i.e., it can be derived directly from an MD trajectory. The performance of ALPHA was tested in detail employing the CBG (corticosteroid binding globulin) affinity of 31 benchmark steroids, supplemented with 11 steroids as an external test set. The only fair (42-50%) correlations of ALPHA with static 3D and electronic descriptors mean that ALPHA forms an independent molecular property. Furthermore, inclusion of ALPHA in the SOMFA/ESP model improves the correlation coefficient from 0.86 to 0.91, and /delta/ave from 0.46 to 0.36 for the benchmark dataset. The predictive ability of ALPHA can be interpreted as indirect evidence of the dynamic contribution to ligand-macromolecule interactions. The physical background of ALPHA is discussed and the importance of molecular motions for biological activity is anticipated.

Ligands↗
PubMed2004

Excitation energies for a benchmark set of molecules obtained within time-dependent current-density functional theory using the Vignale-Kohn functional.

In this article we explain how the existing linear response theory of time-dependent density-functional theory can be extended to obtain excitation energies in the framework of time-dependent current-density-functional theory. We use the Vignale-Kohn current-functional [G. Vignale and W. Kohn, Phys. Rev. Lett. 77, 2037 (1996)] which has proven to be successful for describing ultranonlocal exchange-correlation effects in the case of the axial polarizability of molecular chains [M. van Faassen, P. L. de Boeij, R. van Leeuwen, J. A. Berger, and J. G. Snijders, Phys. Rev. Lett. 88, 186401 (2002); J. Chem. Phys. 118, 1044 (2003)]. We study a variety of singlet excitations for a benchmark set of molecules. The pi(*)<--pi transitions obtained with the Vignale-Kohn functional are in good agreement with experiment and other theoretical results and they are in general an improvement upon the adiabatic local density approximation. In case of the pi(*)<--n transitions the Vignale-Kohn functional fails, giving results that strongly overestimate the experimental and other theoretical results. The benchmark set also contains some other types of excitations for which no clear failures or improvements are observed.

Journal Article↗