ICT Self-efficacy scale: the correlations with the age of first access to the internet, the age at first ownership of a personal computer (PC), and a smartphone.

BACKGROUND: Because of the wide use of information and communication technologies (ICT) in healthcare, medical students' knowledge and skills of modern ICT have been considered essential for their successful learning and future careers. According to Bandura's self-efficacy, enhancing ICT self-efficacy, which might be affected by technology experience, could be a pathway to improving ICT literacy and competence, which should be one focus of medical educationalists. However, there is a lack of suitable measurements of medical students' self-efficacy and a clear understanding of its relationship with technology experience. MATERIALS AND METHODS: We conducted a literature review and direct consultation with an expert panel to identify potential items for the ICT self-efficacy scale. Based on the data collected in a survey of 486 first-year medical students in China, the exploratory factor analysis (EFA) was employed to confirm the structure of the final version. Furthermore, we used linear regressions to quantify the association between ICT self-efficacy and technology experience measured by the age of first access to the Internet, the age at first ownership of a personal computer (PC) or a laptop, and that of a smartphone. RESULTS: The EFA results derived 15 items of four factors, with 67.02% of the total variance explained: Privacy and Safety, Differencing, Communication, and Learning and Application. The Cronbach's alphas for the four subscales and the overall scale ranged from 0.78 to 0.89. Regression results demonstrated a significant association of ICT self-efficacy with age at first ownership of a personal computer (PC) and the mediation role of the general self-efficacy in the ICT self-efficacy's association with the age at first ownership of a personal smartphone. CONCLUSION: The ICT scale developed is a reliable and valid task-specific measure to assess ICT Self-Efficacy for medical students. In addition, enhancing students' technology experience might improve their ICT self-efficacy.

Evidence of Construct Validity of Computer-Based Tests for Clinical Reasoning: Instrument Validation Study.

BACKGROUND: Clinical reasoning (CR) is a fundamental skill for all medical students. In our medical education system, however, there are shortcomings in the conventional methods of teaching CR. New technology is needed to enhance our CR teaching, especially as we are facing an influx of new health trainees. China Medical University (CMU), in response to this need, has developed a computer-based CR training system (CMU-CBCRT). OBJECTIVE: We aimed to find evidence of construct validity of the CMU-CBCRT. METHODS: We recruited 385 students from fifth year undergraduates to postgraduate year (PGY) 3 to complete the test on CMU-CBCRT. The known-groups technique was used to evaluate the construct validity of the CBCRT by comparing the test scores among 4 training levels (fifth year MD, PGY-1, PGY-2, and PGY-3). RESULTS: We found that test scores increased with years of training. Significant differences were found in the test scores on information collection, diagnosis, and treatment and total scores among different training years of participants. However, significant results were not found for treatment errors. CONCLUSIONS: We provided evidence of construct validity of the CMU-CBCRT, which could determine the CR skills of medical students at varying early stage in their careers.

The associations between coping strategies, psychological health, and career indecision among medical students: a cross-sectional study in China.

BACKGROUND: Medical students experience difficulties in the process of making decisions about their careers, which is referred to as career indecision. This study aimed to examine the difficulties in the career decision-making processes of medical students and to explore the association of coping strategies and psychological health with career indecision. The findings may provide a reference for designing interventions to advance satisfying career decisions for medical students. METHODS: A cross-sectional survey of 359 medical students was conducted in 5 Chinese medical schools. Students completed an anonymous self-administered questionnaire measuring their career indecision, coping strategies, and psychological health. Independent t-test, F-test, bivariate Pearson's correlation analysis, and linear regression analysis were applied to test the relation between career indecision and the associated factors. Data were analyzed using SPSS V.22 for Windows. A p-value < 0.05 was considered to be statistically significant. RESULTS: Difficulties regarding lack of readiness frequently occurred in medical students when making career decisions, with the highest score of 2.48 ± 0.58. Among all the associated factors in this study, career indecision was positively associated with psychological distress problem (ß = 0.20, p < 0.05). This study also proved that being at a higher level of career indecision is negatively associated with using problem-focused coping strategies (ß = - 0.14, p < 0.05). For the maladaptive coping strategies, applying dysfunctional coping strategies showed a significantly positive association with career indecision among medical students (ß = 0.25, p < 0.05). CONCLUSIONS: Medical students experienced difficulties regarding lack of readiness frequently when making career decisions. Both coping strategies and psychological health were associated with career indecision among medical students. To prevent career indecision, it is necessary to promote earlier career awareness to medical students. Specifically, psychological health should be addressed in career intervention programs for medical students. Additionally, when helping medical students to cope with career indecision, cognitive techniques that reduce the use of maladaptive coping strategies and enhance the use of adaptive coping strategies should be adopted.

Survey and analysis of the current state of residency training in medical-school-affiliated hospitals in China.

BACKGROUND: Since the global standards for postgraduate medical education (PGME) were published in January 2003, they have gained worldwide attention. The current state of residency training programs in medical-school-affiliated hospitals throughout China was assessed in this study. METHODS: Based on the internationally recognized global standards for PGME, residents undergoing residency training at that time and the relevant residency training instructors and management personnel from 15 medical-school-affiliated hospitals throughout China were recruited and surveyed regarding the current state of residency training programs. A total of 938 questionnaire surveys were distributed between June 30, 2006 and July 30, 2006; of 892 surveys collected, 841 were valid. RESULTS: For six items, the total proportions of "basically meets standards" and "completely meets standards" were <70% for the basic standards. These items were identified in the fields of "training settings and educational resources", "evaluation of training process", and "trainees". In all fields other than "continuous updates", the average scores of the western regions were significantly lower than those of the eastern regions for both the basic and target standards. Specifically, the average scores for the basic standards on as many as 25 of the 38 items in the nine fields were significantly lower in the western regions. There were significant differences in the basic standards scores on 13 of the 38 items among trainees, instructors, and managers. CONCLUSIONS: The residency training programs have achieved satisfactory outcomes in the hospitals affiliated with various medical schools in China. However, overall, the programs remain inadequate in certain areas. For the governments, organizations, and institutions responsible for PGME, such global standards for PGME are a very useful self-assessment tool and can help identify problems, promote reform, and ultimately standardize PGME.

Enhanced dipole moments in trimetallic nitride template endohedral metallofullerenes with the pentalene motif.

Although not found to date in empty-cage fullerenes, the fused pentagon motifs (pentalenes) are allowed in endohedral metallofullerenes (EMFs). We have found that members of the trimetallic nitride template (TNT) EMF Y3N@C2n (n = 39-44) family that contain pentalene motifs exhibit significant dipole moments. This finding is predicted to be significant for other EMFs with a metal atom orientated toward the pentalene motif. Chromatographic retention data and computational results for Y3N@C2-C78, Y3N@Cs-C82, and Y3N@Cs-C84 are examples that pentalene groups lead to a significant induced dipole moment (∼1D). A special case is the Y3N@C2-C78 that contains two pentalenes in a relatively small cage. The (13)C NMR spectrum for Y3N@C2-C78 exhibits strongly deshielded signals for the fullerene cage (155-170 ppm) supporting the presence of the pentalene motif. In addition, a lengthening of the covalent M-N bond in the internal M3N cluster is found for all reported TNT EMFs that contain one or two pentalene motifs.

Electronic properties and 13C NMR structural study of Y3N@C88.

In this paper, we report the synthesis, purification, (13)C NMR, and other characterization studies of Y(3)N@C(88). The (13)C NMR, UV-vis, and chromatographic data suggest an Y(3)N@C(88) having an IPR-allowed cage with D(2)(35)-C(88) symmetry. In earlier density functional theory (DFT) computational and X-ray crystallographic studies, it was reported that lanthanide (A(3)N)(6+) clusters are stabilized in D(2)(35)-C(88) symmetry cages and have reduced HOMO-LUMO gaps relative to other trimetallic nitride endohedral metallofullerene cage systems, for example, A(3)N@C(80). In this paper, we report that the nonlanthanide (Y(3)N)(6+) cluster in the D(2)(35)-C(88) cage exhibits a HOMO-LUMO gap consistent with other lanthanide A(3)N@C(88) molecules based on electrochemical measurements and DFT computational studies. These results suggest that the reduced HOMO-LUMO gap of A(3)N@C(88) systems is a property dominated by the D(2)(35)-C(88) carbon cage and not f-orbital lanthanide electronic metal cluster (A(3)N)(6+) orbital participation.

Synthesis and electrochemical studies of Bingel-Hirsch derivatives of M(3)N@I(h)-C(80) (M=Sc, Lu).

Bingel-Hirsch derivatives of the trimetallic nitride template endohedral metallofullerenes (TNT-EMFs) Sc(3)N@I(h)-C(80) and Lu(3)N@I(h)-C(80) were prepared by reacting these compounds with 2-bromodiethyl malonate, 2-bromo-1,3-dipyrrolidin-1-ylpropane-1,3-dionate bromide, and 9-bromo fluorene. The mono-adducts were isolated and their (1)H NMR spectra showed that the addition occurred with high regioselectivity at the [6,6] bonds of the I(h)-C(80) fullerene cage. Electrochemical analysis showed that the reductive electrochemistry behavior of these derivatives is irreversible at a scan rate of 100 mV s(-1), which is comparable to the behavior of the pristine fullerene species. The first reduction potential of each derivative is either cathodically or anodically shifted by a different value, depending on the attached addend. Bis-adducts containing EtOOC-C-COOEt and HC-COOEt addends were isolated by HPLC and in the case of Sc(3)N@I(h)-C(80) the first reduction potential exhibits a larger shift towards negative potentials when compared to the mono-adduct. This observation is important for designing acceptor materials for the construction of bulk heterojunction (BHJ) organic solar cells, since the polyfunctionalization not only increases the solubility of the fullerene species but also offers a promising approach for bringing the LUMO energy levels closer for the donor and the acceptor materials.

89Y and 13C NMR cluster and carbon cage studies of an yttrium metallofullerene family, Y3N@C(2n) (n = 40-43).

The members of a new family of yttrium trimetallic nitride-templated (TNT) endohedral metallofullerenes (EMFs), Y(3)N@C(2n) (n = 40-43), have been synthesized and purified. On the basis of experimental and computational (13)C NMR studies, we propose cage structures for Y(3)N@I(h)-C(80) (IPR allowed), Y(3)N@D(5h)-C(80) (IPR allowed), Y(3)N@C(s)-C(82) (non-IPR), Y(3)N@C(s)-C(84) (non-IPR), and Y(3)N@D(3)-C(86) (IPR allowed). A significant result is the limited number of isomers found for each carbon cage. For example, there are 24 isolated pentagon rule (IPR) and 51 568 non-IPR structures possible for the C(84) cage, but only one major isomer of Y(3)N@C(s)-C(84) was found. The current study confirms the unique role of the trimetallic nitride (M(3)N)(6+) cluster template in the Kratschmer-Huffman electric-arc process for fullerene cage size and high symmetry isomer selectivity. This study reports the first (89)Y NMR results for Y(3)N@I(h)-C(80,) Y(3)N@C(s)(51365)-C(84), and Y(3)N@D(3)(19)-C(86), which reveal a progression from isotropic to restricted (Y(3)N)(6+) cluster motional processes. Even more surprising is the sensitivity of the (89)Y NMR chemical shift parameter to subtle changes in the electronic environment at each yttrium nuclide in the (Y(3)N)(6+) cluster (more than 200 ppm for these EMFs). This (89)Y NMR study suggests that (89)Y NMR will evolve as a powerful tool for cluster motional studies of EMFs.

Isolation and structural characterization of two very large, and largely empty, endohedral fullerenes: Tm@C(3v)-C(94) and Ca@C(3v)-C(94).

The structures of two newly synthesized endohedral fullerenes, Tm@C(3v)-C(94) and Ca@C(3v)-C(94), have been determined by single crystal X-ray diffraction on samples cocrystallized with Ni(II)(octaethylporphyrin). Both compounds exhibit the same cage geometry and conform to the isolated pentagon rule (IPR). The metal ions within these rather large cages are localized near one end and along the C(3) axis. While the calcium ion is situated over a C-C bond at a 6:6 ring junction, the thulium ion is positioned above a six-membered ring of the fullerene.

M2@C79N (M = Y, Tb): isolation and characterization of stable endohedral metallofullerenes exhibiting M-M bonding interactions inside aza[80]fullerene cages.

Y2@C79N and Tb2@C79N have been prepared by conducting the Kratschmer-Huffman electric-arc process under 20 Torr of N2 and 280 Torr of He with metal oxide-doped graphite rods. These new heterofullerenes were separated from the resulting mixture of empty cage fullerenes and endohedral fullerenes by chemical separation and a two-stage chromatographic process. Crystallographic data for Tb2@C79N x Ni(OEP) x 2 C6H6 demonstrate the presence of an 80-atom cage with idealized I(h) symmetry and two, widely separated Tb atoms inside with a Tb-Tb separation of 3.9020(10) A for the major terbium sites. The EPR spectrum of the odd-electron Y2@C79N indicates that the spin density largely resides on the two equivalent yttrium ions. Computational studies on Y2@C79N suggest that the nitrogen atom resides at a 665 ring junction in the equator on the fullerene cage and that the unpaired electron is localized in a bonding orbital between the two yttrium ions of this stable radical. Thus, the Tb-Tb bond length of the single-electron bond is an exceedingly long metal-metal bond.

Preparation and structural characterization of the Ih and the D5h isomers of the endohedral fullerenes Tm3N@C80: icosahedral C80 cage encapsulation of a trimetallic nitride magnetic cluster with three uncoupled Tm3+ ions.

We report an efficient method for the preparation and purification of the Ih and the D5h isomers of Tm3N@C80. Following preparation in a Kratschmer-Huffman electric-arc generator, the Tm3N@C80 isomers were obtained by a chemical separation process followed by a one-stage isomer selective chromatographic high-performance liquid chromatography (HPLC) separation (pyrenyl, 5PYE column). The HPLC chromatographic retention behavior on a pentabromobenzyl (5PBB) column suggests a charge transfer of approximately 6 electrons; [M3N] 6+@C80(6-) and the chromatographic retention mechanisms of the Ih and the D5h isomers of Tm3N@C80 on both 5PBB and 5PYE columns are discussed. Single-crystal X-ray diffraction data demonstrate that the Tm3N cluster has a planar structure but represents a tight fit for trapping the Tm3N cluster inside the I h - and the D 5h -C 80 cages. Specifically, the Tm atoms punch out the cage carbon atoms adjacent to them. The "punched out" effect can be demonstrated by cage radii and pyramidal angles at cage carbon atoms near the Tm atoms. The magnetic susceptibility (chiT) for Tm3N@ Ih -C80 was found to exhibit Curie-Weiss behavior with C = 23.4 emu.K/mol, which is consistent with the calculated value for three uncoupled Tm3+ ions by considering the spin and orbital contributions with no quenching of the orbital angular momentum ( L = 5, S = 1, and J = 6; Ccalcd = 23.3 emu.K/mol). The electrochemical measurements demonstrate that both the Ih and the D5h isomers of Tm3N@C80 have a large electrochemical gap.

New egg-shaped fullerenes: non-isolated pentagon structures of Tm3N@C(s)(51 365)-C84 and Gd3N@C(s)(51 365)-C84.

Although there are 51 568 non-IPR and 24 IPR structures for C84, the egg-shaped endohedral fullerenes Tm3N@C(s)(51 365)-C84 and Gd3N@C(s)(51 365)-C84 utilize the same non-IPR cage structure as found initially for Tb3N@C(s)(51 365)-C84.

HIV/AIDS Knowledge, Attitudes, and Behaviors of Construction Workers in China.

The objective of the study was to describe HIV/AIDS knowledge, attitudes, risk behaviors, and sources of information among construction workers in China. A cross-sectional survey of 458 construction workers was conducted among 4 construction sites in Shenyang city in 2006. All 458 participants were individually interviewed in a private setting by a trained team of medical researchers using a structured questionnaire, which included questions on general personal information and the knowledge, attitudes, practice questions and the favorable mode of health education. A total of 428 valid questionnaires were collected. Data entry and statistical analyses were performed using the SPSS 13.0. Our results indicated that the majority of construction workers in China are sexually active youths and adults with limited education and poor knowledge of HIV/AIDS. The proportions of correct answers to questions about HIV/AIDS ranged from 4.9% to 70.7%. The score was significantly different by education level (χ(2)=47.51, p<0.01), and marrital status (χ(2)=16.48, p<0.01). More than 60% of the construction workers had a negative attitude toward HIV/AIDS-infected individuals. The source of workers' knowledge toward HIV/AIDS mainly came from TV (35.8%), newspaper (14.3%), family and friend (13.1%) and others (28.2%). Chinese migrant workers in general lack knowledge about HIV/AIDS. Our study suggests prevention programs should be encouraged and these may have the potential role to limit the emergence of China's HIV/AIDS epidemic.

Manganese(III)-catalyzed free radical reactions on trimetallic nitride endohedral metallofullerenes.

The first reactions of trimetallic nitride templated endohedral metallofullerenes (TNT EMFs) with carbon radicals generated from diethyl malonate catalyzed by manganese(III) acetate are reported. Two methano monoadducts, Sc3N@C80-A and Sc3N@C80-B, were isolated and characterized. Sc3N@C80-A contains two ester moieties, whereas Sc3N@C80-B contains only one ester group and a hydrogen atom on the central carbon of the addend. NMR spectroscopy of the two monoadducts suggests that the addition occurs regioselectively at a 6,6-ring juncture on the surface of the icosahedrally (Ih) symmetric Sc3N@C80, forming the first 6,6-ring-bridged methano Ih Sc3N@C80 derivatives. The measured 1J(C,H) = 147 Hz for the methano carbon with its hydrogen in monoadduct Sc3N@C80-B nearly perfectly matches the data for pi-homoaromatic systems, indicating an open [6,6]-methano structure. Geometry optimization also found that the "closed" [6,6]-methano structures were energetically unstable and always led to the open forms. Thus, an "open" [6,6]-methanofulleride structure is proposed, which was induced by the norcaradiene rearrangement, resulting in the cleavage of the cyclopropane ring and the formation of energetically stable open cage fullerene derivatives. These are the first examples of thermodynamically stable adducts of the "open" type at the 6,6-ring juncture of Ih Sc3N@C80, differing greatly from the "closed" 5,6-ring juncture adducts reported previously. In addition, bis-, tri-, and up to octaadducts of Sc3N@C80 were detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry; this synthetic method was also applied to Lu3N@C80, producing adducts with up to 10 substituents on the carbon cage. These are the highest levels of substitution of TNT metallofullerenes reported so far.

Isolation and structural characterization of a family of endohedral fullerenes including the large, chiral cage fullerenes Tb(3)N@C(88) and Tb(3)N@C(86) as well as the I(h) and D(5)(h) isomers of Tb(3)N@C(80).

The recent finding that isomer 2 of Tb(3)N@C(84) uses one of the 51,568 possible nonisolated pentagon rule (non-IPR) structures for the C(84) cage rather than one of the 24 cage isomers that do obey the IPR suggests that further experimental work on the structure of larger endohedrals is needed to observe the utility of the IPR rule in this uncharted territory. The structures of the newly synthesized endohedral fullerenes--Tb(3)N@C(88), Tb(3)N@C(86), and the Ih and D(5)(h) isomers of Tb(3)N@C(80)--have been determined by single-crystal X-ray diffraction on samples cocrystallized with NiII(octaethylporphyrin). In contrast to the situation for isomer 2 of Tb(3)N@C(84), the structures of Tb(3)N@C(88) and Tb(3)N@C(86) do conform to the IPR. Both Tb(3)N@C(88) and Tb(3)N@C(86) have chiral structures with D(2) symmetry for Tb(3)N@C(880 and D(3) symmetry for Tb(3)N@C(86). Within this group of endohedrals, the size of the carbon cage affects the Tb-N and Tb-C distances, the orientations of the carbon cage with respect to the porphyrin plane, the locations of the metal ions and their orientations relative to the porphyrin plane, and the degree of pyramidalization of the Tb(3)N unit.

Tb3N@C84: an improbable, egg-shaped endohedral fullerene that violates the isolated pentagon rule.

The structure of isomer 2 of Tb3N@C84 has been determined through single-crystal X-ray diffraction on Tb3N@C84.NiII(OEP).2(C6H6). The carbon cage has a distinct egg shape due to the presence of a single pair of fused pentagons at one apex of the molecule. Thus, although 24 IPR structures are available to the C84 cage, Nature utilizes one of the 51 568 isomeric structures that do not conform to the IPR for this unusual molecule. The Tb3N portion of isomer 2 of Tb3N@C84 is strictly planar. One Tb atom is nestled within the fold of the fused pentagons, while the other Tb atoms are disordered over four pairs of sites.

Preparation and structure of CeSc2N@C80: an icosahedral carbon cage enclosing an acentric CeSc2N unit with buried f electron spin.

Herein, we report the preparation, purification, and characterization of a mixed trimetallic nitride endohedral metallofullerene, CeSc(2)N@C(80). Single-crystal X-ray diffraction shows that CeSc(2)N@C(80) consists of a four-atom asymmetric top (CeSc(2)N) inside a C(80) (I(h)()) carbon cage. Unlike the situation in most endohedrals of the M(3)N@C(2)(n)() type, the nitride ion is not located at the center of the carbon cage but is offset by 0.36 A in order to accommodate the large Ce(III) ion. The cage carbon atoms near the endohedral Ce and Sc atoms exhibit significantly larger pyramidal angles than the other carbon atoms on the C(80) cage. Surprisingly, at ambient temperature, the (13)C NMR spectrum exhibits isotropic motional averaging yielding only two signals (3 to 1 intensity ratio) for the icosahedral C(80) cage carbons. At the same temperature, the (45)Sc NMR exhibits a relatively narrow, symmetric signal (2700 Hz) with a small temperature-dependent Curie shift. A rotation energy barrier (E(a) = 79 meV) was derived from the (45)Sc NMR line-width analysis. Finally, the XPS spectrum for CeSc(2)N@C(80) confirms a +3 oxidation state for cerium, Ce(3+)(4f(1)5d(0)). This oxidation state and the Curie shift are consistent with a weakly paramagnetic system with a single buried f electron spin.

Structure and enhanced reactivity rates of the D5h Sc3N@C80 and Lu3N@C80 metallofullerene isomers: the importance of the pyracylene motif.

In this paper we report enhanced reactivity of the D(5h) isomers in comparison with the more common I(h) isomers of Sc(3)N@C(80) and Lu(3)N@C(80) toward Diels-Alder and 1,3-dipolar tritylazomethine ylide cycloaddition reactions. Also, the structure of the D(5h) isomer of Sc(3)N@C(80) has been determined through single-crystal X-ray diffraction on D(5h)-Sc(3)N@C(80).Ni(OEP).2benzene (OEP = octaethylporphyrin). The Sc(3)N portion of D(5h)-Sc(3)N@C(80) is strictly planar, but the plane of these four atoms is tipped out of the noncrystallographic, horizontal mirror plane of the fullerene by 30 degrees . The combination of short bond length and high degree of pyramidization for the central carbon atoms of the pyracylene sites situated along a belt that is perpendicular to the C(5) axis suggests that these are the sites of greatest reactivity in the D(5h) isomer of Sc(3)N@C(80). Consistent with the observation of higher reactivity observed for the D(5h) isomers, cyclic voltammetry and molecular orbital (MO) calculations demonstrate that the D(5h) isomers have slightly smaller energy gaps than those of the I(h) isomers. The first mono- and bis-adducts of D(5h) Sc(3)N@C(80) have been synthesized via 1,3-dipolar cycloaddition of tritylazomethine ylide. The NMR spectrum for the monoadduct 2b is consistent with reaction at the 6,6-ring juncture in the pyracylene unit of the D(5h) Sc(3)N@C(80) cage and is the thermodynamically stable isomer. On the other hand, monoadduct 2a undergoes thermal conversion to other isomeric monoadducts, and three possible structures are proposed.