Potential energy surfaces for singlet and triplet states of the LiH2+ system and quasi-classical trajectory cross sections for H + LiH+ and H+ + LiH.

A new set of six accurate ab initio potential energy surfaces (PESs) is presented for the first three singlet and triplet states of LiH2+ (1,21A', 11A'', 1,23A', and 13A'' states, where four of them are investigated for the first time), which have allowed new detailed studies gaining a global view on this interesting system. These states are relevant for the study of the most important reactions of lithium chemistry in the early universe. More than 45 000 energy points were calculated using the multi-reference configuration interaction level of theory using explicitly correlated methods (ic-MRCI-F12), and the results obtained for each individual electronic state were fitted to an analytical function. Using quasiclassical trajectories and considering the initial diatomic fragment in the ground rovibrational state, we have determined the integral cross sections for the H + LiH+(X2Σ+, C2Π) and H+ + LiH(X1Σ+, B1Π) reactions. In these calculations all available reaction channels were considered: the chemically most important H or H+ transfer/abstraction as well as atom exchange and collision induced dissociation for up to 1.0 eV of collision energy.

An experimental comparison of multiple-choice and short-answer questions on a high-stakes test for medical students.

Recent advances in automated scoring technology have made it practical to replace multiple-choice questions (MCQs) with short-answer questions (SAQs) in large-scale, high-stakes assessments. However, most previous research comparing these formats has used small examinee samples testing under low-stakes conditions. Additionally, previous studies have not reported on the time required to respond to the two item types. This study compares the difficulty, discrimination, and time requirements for the two formats when examinees responded as part of a large-scale, high-stakes assessment. Seventy-one MCQs were converted to SAQs. These matched items were randomly assigned to examinees completing a high-stakes assessment of internal medicine. No examinee saw the same item in both formats. Items administered in the SAQ format were generally more difficult than items in the MCQ format. The discrimination index for SAQs was modestly higher than that for MCQs and response times were substantially higher for SAQs. These results support the interchangeability of MCQs and SAQs. When it is important that the examinee generate the response rather than selecting it, SAQs may be preferred. The results relating to difficulty and discrimination reported in this paper are consistent with those of previous studies. The results on the relative time requirements for the two formats suggest that with a fixed testing time fewer SAQs can be administered, this limitation more than makes up for the higher discrimination that has been reported for SAQs. We additionally examine the extent to which increased difficulty may directly impact the discrimination of SAQs.

Exploring the Validity Based on Internal Structure of the Oldenburg Burnout Inventory - Medical Student (OLBI-MS).

CONSTRUCT: The study gathers validity evidence for the use of the Oldenburg Burnout Inventory - Medical Student (OLBI-MS), a 16-item scale used to measure medical student burnout. The 16 items on the OLBI-MS are split to form two subscales, disengagement and exhaustion. BACKGROUND: Medical student burnout has been empirically linked to several detrimental professional and personal consequences. In recognition of the high prevalence of medical student burnout, one recommendation has been to regularly measure burnout using standardized measures that have strong validity evidence for their intended use. The OLBI-MS, a frequently used measure of medical student burnout, was adapted from the Oldenburg Burnout Inventory (OLBI). The OLBI has been studied in many occupational settings and been found to have a two-factor solution in majority of these populations, but there is limited validity evidence available that supports the use of the OLBI-MS subscales in a medical student population. APPROACH: Two years of Association of American Medical College Year 2 Questionnaire data (n = 24,008) were used in the study for a series of exploratory and confirmatory factor analyses. The data from the first year (n = 11,586) was randomly split into a confirmatory and exploratory sample, with the data from the second year (n = 12,422) used as a secondary confirmatory sample. Because the questionnaire is administered to medical students during their second year of undergraduate medical education, we consider this a study as providing validity evidence specifically for the measure's use with that population. FINDINGS: The two-factor structure of the OLBI-MS was not empirically supported in the second year medical-student population. Several of the items had low inter-item correlations and/or moderate correlations with unexpected items. Three modified versions of the OLBI-MS were tested using subsets of the original items. Two of the modified versions were adequate statistical explanations of the relationships in the data. However, it is unclear if these revised scales appropriately measure all aspects of the construct of burnout and additional validity evidence is needed prior to their use. CONCLUSIONS: The use of the OLBI-MS is not recommended for measuring second-year medical student burnout. It is unclear if the OLBI-MS is appropriate for medical students at all, or if different measures are necessary at different stages in a medical student's professional development. Additional research is needed to either improve the OLBI-MS or use it as a foundation for a new measure.Supplemental data for this article is available online at at www.tandfonline.com/htlm .

Assessing the validity of test scores using response process data from an eye-tracking study: a new approach.

Understanding the response process used by test takers when responding to multiple-choice questions (MCQs) is particularly important in evaluating the validity of score interpretations. Previous authors have recommended eye-tracking technology as a useful approach for collecting data on the processes test taker's use to respond to test questions. This study proposes a new method for evaluating alternative score interpretations by using eye-tracking data and machine learning. We collect eye-tracking data from 26 students responding to clinical MCQs. Analysis is performed by providing 119 eye-tracking features as input for a machine-learning model aiming to classify correct and incorrect responses. The predictive power of various combinations of features within the model is evaluated to understand how different feature interactions contribute to the predictions. The emerging eye-movement patterns indicate that incorrect responses are associated with working from the options to the stem. By contrast, correct responses are associated with working from the stem to the options, spending more time on reading the problem carefully, and a more decisive selection of a response option. The results suggest that the behaviours associated with correct responses are aligned with the real-world model used for score interpretation, while those associated with incorrect responses are not. To the best of our knowledge, this is the first study to perform data-driven, machine-learning experiments with eye-tracking data for the purpose of evaluating score interpretation validity.

Investigation of answer changes on the USMLE® Step 2 Clinical Knowledge examination.

BACKGROUND: Examinees often believe that changing answers will lower their scores; however, empirical studies suggest that allowing examinees to change responses may improve their performance in classroom assessments. To date, no studies have been able to examine answer changes during large scale professional credentialing or licensing examinations. METHODS: In this study, we expand the research on answer changes by analyzing responses from 27,830 examinees who completed the Step 2 Clinical Knowledge (CK) examination between August of 2015 and August of 2016. RESULTS: The results showed that although 68% of examinees changed at least one item, the overall average number of changes was small. Among the examinees who changed answers, approximately 45% increased their scores and approximately 28% decreased their scores. On average, examinees spent shortest time on the item changes from wrong to right and they were more likely to change their scores from wrong to right than right to wrong. CONCLUSIONS: Consistent with previous studies, these findings support the beneficial effects of answer changes in high-stakes medical examinations and suggest that examinees who are overly cautious about changing answers may put themselves at a disadvantage.

Vibrational energy relaxation dynamics of diatomic molecules inside superfluid helium nanodroplets. The case of the I2 molecule.

The vibrational energy relaxation (VER) of a homonuclear diatomic molecule (X2) in a 4He superfluid nanodroplet (HeND; T = 0.37 K) was studied adapting appropriately a hybrid theoretical quantum approach recently proposed by us. In the first application the interesting case of the I2(X) molecule was examined and, as far as we know, this corresponds to the first theoretical investigation on the VER of molecules embedded in HeND. Vibrational relaxation of I2 takes place according to a cascade mechanism [sequential transitions between two consecutive vibrational levels (ν → ν - 1; ν - 1 → ν - 2; …; 2 → 1; 1 → 0), where an arbitrary relaxation, e.g., ν - 1 → ν - 2, can only occur once the previous relaxation has taken place, and so on]. The global relaxation from the initial excited state ν down to the ground state (ν = 0) happens on the nanosecond scale. Data on the VER of molecules in HeND are very scarce and a vibrational lifetime not far from the I2 one for ν = 1 has been estimated experimentally for Na3(24E') on HeND (a qualitatively similar 0 → 1 vibrational energy gap occurs in both species), but metastability has not been reported in the second case. The cascade mechanism was understood once the values of the coupling matrix elements were examined, and the time evolution of the populations of two consecutive vibrational levels was adequately described using a non-linear two-state Hamiltonian model for I2 in the HeND. According to the calculations, superfluid liquid helium is very efficient in releasing the excess of energy arising from the I2 vibrational de-excitation, as it should be. However, the number of He atoms evaporated is small compared to what is expected. We hope that this first theoretical work on the molecular VER dynamics in HeND will encourage researchers to investigate this important process about which we still know very little.

Dynamics of the O + H2+ → OH+ + H, OH + H+ proton and hydrogen atom transfer reactions on the two lowest potential energy surfaces.

The dynamics of the title reaction was studied using mainly the quasiclassical trajectory (QCT) method on the ground 12A'' (OH+ channel) and first excited 12A' (OH channel) potential energy surfaces (PESs) employing ab initio analytical representations of the PESs developed by us. Both PESs correspond to exoergic reactions, are barrierless and present a deep minimum along the minimum energy path (MEP). Some extra calculations (cross sections) were also performed with the time dependent quantum real wave packet method at the centrifugal sudden level (RWP-CS method). A broad set of properties as a function of collision energy (Ecol ≤ 0.5 eV) was considered using the QCT method: cross sections, average fractions of energy, product rovibrational distributions, two- and three-vector properties, and the microscopic mechanisms analyzing their influence on the dynamics. The proton transfer channel dominates the reactivity of the system and significant differences between the two reaction channels are found for the vibrational distributions and microscopic mechanisms. The results were interpreted according to the properties of the ground and excited PESs. Moreover, the QCT and RWP-CS cross sections are in rather good agreement for both reaction channels. We hope that this study will encourage the experimentalists to investigate the dynamics of this interesting but scarcely studied system, whose two lowest PESs include the ground and first excited electronic states of the H2O+ cation.

Testing and evaluation: the present and future of the assessment of medical professionals.

The aim of this review is to highlight recent and potential future enhancements to the United States Licensing Examination (USMLE) program. The USMLE program is co-owned by the National Board of Medical Examiners (NBME) and the Federation of State Medical Boards. The USMLE includes four examinations: Step 1, Step 2 Clinical Knowledge, Step 2 Clinical Skills, and Step 3; every graduate of Liaison Committee on Medical Education-accredited allopathic medical schools and all international medical graduates must pass this examination series to practice medicine in the United States. From 2006 to 2009, the program underwent an indepth review resulting in five accepted recommendations. These recommendations have been the primary driver for many of the recent enhancements, such as an increased emphasis on foundational science and changes in the clinical skills examination, including more advanced communication skills assessment. These recommendations will continue to inform future changes such as access to references (e.g., a map of metabolic pathways) or decision-making tools for use during the examination. The NBME also provides assessment services globally to medical schools, students, residency programs, and residents. In 2015, >550,000 assessments were provided through the subject examination program, NBME self-assessment services, and customized assessment services.

Born-Oppenheimer and Renner-Teller coupled-channel quantum reaction dynamics of O((3)P) + H2(+)(X(2)Σg(+)) collisions.

We present Born-Oppenheimer (BO) and Renner-Teller (RT) time dependent quantum dynamics studies of the reactions O((3)P) + H2(+)(X(2)Σg(+)) → OH(+)(X(3)Σ(-)) + H((2)S) and OH(X(2)Π) + H(+). We consider the OH2(+) X[combining tilde](2)A'' and Ã(2)A' electronic states that correlate with a linear (2)Π species. The electronic angular momenta operators L[combining circumflex] and L[combining circumflex](2) are considered in nonadiabatic coupled-channel calculations, where the associated RT effects are due to diagonal V(RT) potentials that add up to the PESs and to off-diagonal C(RT) couplings between the potential energy surfaces (PESs). Initial-state-resolved reaction probabilities PI, integral cross sections σI, and rate constants kI are obtained using recent ab initio PESs and couplings and the real wavepacket formalism. Because the PESs are strongly attractive, PI have no threshold energy and are large, σI decrease with collision energy, and kI depend little on the temperature. The X[combining tilde](2)A'' PES is up to three times more reactive than the Ã(2)A' PES and H2(+) rotational effects (j0 = 0, 1) are negligible. The diagonal V(RT) potentials are strongly repulsive at the collinearity and nearly halve all low-energy observables with respect to the BO ones. The off-diagonal C(RT) couplings are important at low partial waves, where they mix the X[combining tilde](2)A'' and Ã(2)A' states up to ∼20%. However, V(RT) effects predominate over the C(RT) ones that change at most by ∼19% the BO values of σI and kI. The reaction O((3)P) + H2(+)(X(2)Σg(+)) → OH(+)(X(3)Σ(-)) + H((2)S) is probably one of the most reactive atom + diatom collisions because its RT rate constant at room temperature is equal to 2.26 × 10(-10) cm(3) s(-1). Within the BO approximation, the present results agree rather well with recent quasiclassical and centrifugal-sudden data using the same PESs.

Complexity in graduate medical education: a collaborative education agenda for internal medicine and geriatric medicine.

Internal medicine residents today face significant challenges in caring for an increasingly complex patient population within ever-changing education and health care environments. As a result, medical educators, health care system leaders, payers, and patients are demanding change and accountability in graduate medical education (GME). A 2012 Society of General Internal Medicine (SGIM) retreat identified medical education as an area for collaboration between internal medicine and geriatric medicine. The authors first determined a short-term research agenda for resident education by mapping selected internal medicine reporting milestones to geriatrics competencies, and listing available sample learner assessment tools. Next, the authors proposed a strategy for long-term collaboration in three priority areas in clinical medicine that are challenging for residents today: (1) team-based care, (2) transitions and readmissions, and (3) multi-morbidity. The short-term agenda focuses on learner assessment, while the long-term agenda allows for program evaluation and improvement. This model of collaboration in medical education combines the resources and expertise of internal medicine and geriatric medicine educators with the goal of increasing innovation and improving outcomes in GME targeting the needs of our residents and their patients.

Potential energy surfaces and quasiclassical trajectory study of the O + H2(+)→ OH(+) + H, OH + H(+) proton and hydrogen atom transfer reactions and isotopic variants (D2(+), HD(+)).

The rate constants (k; T: 200-900 K) and cross-sections (σ; Ecol: 0.010-0.50 eV) of the O + H2(+)→ OH(+) + H (1), OH + H(+) (2) reactions, which occur on the ground (1(2)A'') and first excited (1(2)A') potential energy surfaces (PESs), respectively, were investigated for the first time, considering also the rate constants for D2(+) and HD(+). Ab initio multireference configuration interaction calculations were performed on both barrierless PESs (where the minimum energy path involves the insertion of the O atom into the middle of the H2(+) bond), and suitable analytical expressions were developed for the first time and used in quasiclassical trajectory (QCT) calculations. k(1) ≈ 3k(2) independent of the isotopic variant, k(H2(+)) > k(HD(+)) > k(D2(+)) for , and the intermolecular and intramolecular isotopic effects are essentially independent of T. Comparison with the Langevin-Gioumousis-Stevenson (LGS) simple capture model shows that these results are similar to the QCT ones, especially for ; and the isotopic effects are coincident with the QCT ones for both reactions. For O + H2(+), σ(1) ≈ 3σ(2) at Ecol≤ 0.10 eV, and σ(1) = 1.5σ(2) at 0.40 and 0.50 eV. The larger value of σ(1(2)A'') with respect to σ(1(2)A') arises from the larger value of bmax(1(2)A'') with respect to bmax(1(2)A'), and this results from the more attractive character of the former PES. Besides, the reaction probabilities are quite large [0.78-0.98 (1(2)A'') and 0.78-0.93 (1(2)A')], and the decreasing trend of both cross-sections as Ecol increases arises from the barrierless character of both PESs. We expect that these results (in particular, the competition between proton transfer and hydrogen atom transfer) will encourage experimentalists to carry out investigations on this interesting reaction.

A Comparison of Remote vs In-Person Proctored In-Training Examination Administration for Internal Medicine.

PURPOSE: In response to COVID-19, the American College of Physicians provided residents the option to complete the 2020 Internal Medicine In-Training Examination (IM-ITE) via in-person and remote proctoring. This study evaluated the extent to which scores obtained from both testing modalities were comparable. METHOD: Data were analyzed from residents from all U.S.-based Accreditation Council for Graduate Medical Education-accredited IM residency programs and participating Canadian and international programs who completed the IM-ITE in 2020. The final sample contained 27,115 IM residents: 9,205 postgraduate year (PGY) 1, 9,332 PGY-2, and 8,578 PGY-3. Testing modality, gender, PGY, time spent on assessment, and native language were used to predict percent-correct scores in a multilevel regression model. This model included all main effects and all 2-way interactions between testing modality and each resident-level demographic variable, allowing those effects to be controlled for. RESULTS: Of 27,115 residents studied, 11,354 (42%) tested remotely and 15,761 (58%) in person. Across the parameters of interest (main effect of testing modality and 2-way interactions), the only statistically significant effects were the interaction effects between testing mode (interaction effect: -0.61; 95% confidence interval [CI], -1.01 to -0.21) and PGY (interaction effect: -0.54; 95% CI, -0.95 to -0.13) ( P = .002). Differences between in-person and remote predicted scores were slightly larger for PGY-1 than for PGY-2 and PGY-3 residents, but the magnitude of these differences across residency training was well under one percentage point. Because these statistically significant effects were deemed educationally nonsignificant, the study concluded that performance did not substantively differ across in-person and remote examinees. CONCLUSIONS: Residents taking the 2020 IM-ITE performed similarly across in-person and remote proctoring. This study provides evidence of score comparability across the 2 testing modalities and supports continued use of remote proctoring for the IM-ITE.

SHARP (SHort Answer, Rationale Provision): A New Item Format to Assess Clinical Reasoning.

PROBLEM: Many non-workplace-based assessments do not provide good evidence of a learner's problem representation or ability to provide a rationale for a clinical decision they have made. Exceptions include assessment formats that require resource-intensive administration and scoring. This article reports on research efforts toward building a scalable non-workplace-based assessment format that was specifically developed to capture evidence of a learner's ability to provide a justification for a clinical decision that they had made. APPROACH: The authors developed a 2-step item format called SHARP (SHort Answer, Rationale Provision), referring to the 2 tasks that comprise the item. In collaboration with physician-educators, the authors integrated short-answer questions into a patient medical record-based item starting in October 2021 and arrived at an innovative item format in December 2021. In this format, a test-taker interprets patient medical record data to make a clinical decision, types in their response, and pinpoints medical record details that justify their answers. In January 2022, a total of 177 fourth-year medical students, representing 20 U.S. medical schools, completed 35 SHARP items in a proof-of-concept study. OUTCOMES: Primary outcomes were item timing, difficulty, reliability, and scoring ease. There was substantial variability in item difficulty, with the average item answered correctly by 44% of students (range, 4%-76%). The estimated reliability (Cronbach α) of the set of SHARP items was 0.76 (95% CI, 0.70-0.80). Item scoring is fully automated, minimizing resource requirements. NEXT STEPS: A larger study is planned to gather additional validity evidence about the item format. This study will allow comparisons between performance on SHARP items and other examinations, the examination of group differences in performance, and possible use cases for formative assessment purposes. Cognitive interviews are also planned to better understand the thought processes of medical students as they work through the SHARP items.

Full dimensional potential energy surface for the ground state of H4(+) system based on triatomic-in-molecules formalism.

In this work, we present a global potential energy surface for the ground electronic state of the H4(+) based on ab initio calculations. The final fit is based on triatomics-in-molecules (TRIM) approximation and it includes extra four-body terms for the better description of some discrepancies found on the TRIM model. The TRIM method itself allows a very accurate description of the asymptotic regions. The global fit uses more than 19,000 multireference configuration interaction ab initio points. The global potential energy surface has an overall root mean square error of 0.013 eV for energies up to 2 eV above the global minimum. This work presents an analysis of the stationary points, reactant and product channels, and crossing between the two lowest TRIM adiabatic states. It is as well included a brief description of the two first excited states of the TRIM matrix, concluding that TRIM method is a very good approximation not only for the ground state but also for at least two of the excited states of H4(+) system.

A Clear Cell Sarcoma Case: A Diagnostic and Treatment Challenge, with a Promising Response to Trabectedin.

Introduction: Clear cell sarcoma (CCS) is a rare and aggressive soft tissue sarcoma. CCS is characterized by the translocation t(12;22) (q13;q12), involving the fusion of EWSR1 and ATF1 genes, and less frequently the fusion gene EWSR1-CREB1. Usually, CCSs are considered poorly responsive to conventional chemotherapy. However, trabectedin has shown activity against translocation-related sarcomas. Furthermore, preclinical results suggest that trabectedin is a promising antitumor agent for CCS, potentially inducing melanocytic differentiation. Case Presentation: We report the case of a challenging anatomopathological diagnosis in a patient with an aggressive metastatic CCS. Following the diagnosis of CCS, the patient experienced a clinical and radiological tumor response to trabectedin after four lines of treatment. Conclusion: This is a novel report of CCS treated with trabectedin that resulted in a partial response and suggests the need for further research on trabectedin as a therapeutic option for CCS.

Casein phosphopeptides drastically increase the secretion of extracellular proteins in Aspergillus awamori. Proteomics studies reveal changes in the secretory pathway.

BACKGROUND: The secretion of heterologous animal proteins in filamentous fungi is usually limited by bottlenecks in the vesicle-mediated secretory pathway. RESULTS: Using the secretion of bovine chymosin in Aspergillus awamori as a model, we found a drastic increase (40 to 80-fold) in cells grown with casein or casein phosphopeptides (CPPs). CPPs are rich in phosphoserine, but phosphoserine itself did not increase the secretion of chymosin. The stimulatory effect is reduced about 50% using partially dephosphorylated casein and is not exerted by casamino acids. The phosphopeptides effect was not exerted at transcriptional level, but instead, it was clearly observed on the secretion of chymosin by immunodetection analysis. Proteomics studies revealed very interesting metabolic changes in response to phosphopeptides supplementation. The oxidative metabolism was reduced, since enzymes involved in fermentative processes were overrepresented. An oxygen-binding hemoglobin-like protein was overrepresented in the proteome following phosphopeptides addition. Most interestingly, the intracellular pre-protein enzymes, including pre-prochymosin, were depleted (most of them are underrepresented in the intracellular proteome after the addition of CPPs), whereas the extracellular mature form of several of these secretable proteins and cell-wall biosynthetic enzymes was greatly overrepresented in the secretome of phosphopeptides-supplemented cells. Another important 'moonlighting' protein (glyceraldehyde-3-phosphate dehydrogenase), which has been described to have vesicle fusogenic and cytoskeleton formation modulating activities, was clearly overrepresented in phosphopeptides-supplemented cells. CONCLUSIONS: In summary, CPPs cause the reprogramming of cellular metabolism, which leads to massive secretion of extracellular proteins.

COP2ING With a New Normal: Navigating the Return to Society for Older Adults With Dementia and Their Caregivers.

COVID-19 has stressed the healthcare system in ways our society has not seen before. Less visibly, elderly patients and their caregivers have been stressed as well, both by the virus and by the public health measures required to slow its spread. After months of isolating, patients with dementia and their caregivers are worried about reentering a society with different rules and expectations. Although an extremely complex topic, the re-entry of individuals with cognitive impairment back into society is critical for both the wellbeing of the person as well as the caregiver. Successful re-entry into society will vary based on a person's interests and baseline cognition, however, the ability to participate in activities and events that previously provided joy and stimulation is the first step. This paper, written by practicing geriatricians and palliative clinicians, offers some concrete counseling strategies and tips for caregivers to help navigate re-entry into society with their loved ones.

A Natural-Language-Processing-Based Procedure for Generating Distractors for Multiple-Choice Questions.

One of the most challenging aspects of writing multiple-choice test questions is identifying plausible incorrect response options-i.e., distractors. To help with this task, a procedure is introduced that can mine existing item banks for potential distractors by considering the similarities between a new item's stem and answer and the stems and response options for items in the bank. This approach uses natural language processing to measure similarity and requires a substantial pool of items for constructing the generating model. The procedure is demonstrated with data from the United States Medical Licensing Examination (USMLE®). For about half the items in the study, at least one of the top three system-produced candidates matched a human-produced distractor exactly; and for about one quarter of the items, two of the top three candidates matched human-produced distractors. A study was conducted in which a sample of system-produced candidates were shown to 10 experienced item writers. Overall, participants thought about 81% of the candidates were on topic and 56% would help human item writers with the task of writing distractors.

Patient transfer forms enhance key information between nursing homes and emergency department.

The purpose of this study was to determine whether the use of a transfer form increases the availability of essential information needed for patient care and to examine its effect on case resolution time and disposition status. A retrospective review was performed that included patients 65 years old or greater arriving from nursing homes to an academic Emergency Department from January to June 2009. Eighty randomly selected charts were reviewed. Sixteen items were deemed essential based on an expert-based rubric published in 2006. Each case was scored accordingly. Results indicate that the transfer form group had available, on average, 71% of the essential items as compared to 28% for cases without a transfer form (p < 0.001). There was no difference in the case resolution time (p = 0.94) or in disposition status (p = 0.12). In conclusion, essential information for providing emergency department patient care was significantly increased with the use of a transfer form.

Potential energy surface and reactive collisions for the Au+H(2) system.

A global potential energy surface is obtained for the ground state of the endoergic Au((2)S)+H(2)(X (1)Sigma(g) (+))-->AuH((1)Sigma(+))+H((2)S) reaction. The global potential is obtained by fitting highly correlated ab initio calculations on the system, using relativistic pseudopotential for the gold atom. Several electronic states are calculated correlating with Au((2)S)+H(2), Au((2)D)+H(2), and H(2), Au((2)P)+H(2) asymptotes. These states show several conical intersections and curve crossings along the minimum energy reaction path which are analyzed in detail. One of them gives rise to an insertion well in which there are important contributions from the Au((2)D) and Au((2)P) states of gold, which is interesting because it is analog to the deep chemisorption well appearing in larger gold clusters. Quantum wave packet and quasiclassical trajectory dynamical calculations performed for the reaction at zero total angular momentum are in good agreement, provided that a Gaussian binning method is used to account for the zero-point energy of products. Finally, integral and differential cross sections are calculated for the reaction with quasiclassical trajectories. Two different reaction mechanisms are found, one direct and the second indirect, in which the Au atom inserts in between the two hydrogen atoms because of the existence of the insertion well discussed above.