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Several 2-substituted (H, Ph, and S-Me) and 1-substituted (H, Ph, and Bn), 3-hydroxy-1,3-quinazolin(di)ones were utilized for the first time as radical trapping agents in asymmetric 1,2-oxytrifluoromethylation of styrenes catalyzed by chiral vanadyl methoxide complexes bearing 3,5-disubstituted-N-salicylidene-t-leucinate templates. The effects of catalysts and solvents on the asymmetric induction were systematically examined. The best and complementary scenarios involved the use of vanadyl complexes V(O)-1 and V(O)-2, which bear 3-(2,5-dimethyl)phenyl-5-bromophenyl and 3-t-butyl-5-bromophenyl groups in an i-propanol solvent at ambient temperature. The corresponding (R)-cross-coupling products by V(O)-1 were obtained in 45–71% (for 2-substituted series) and 59–93% yields (for 1-substituted series) for p-/m-methylstyrenes and m-halo/CF3/CO2Me-styrenes in 38–63% ees (the best in 2-H case) and 60–84% ees (the best in 1-benzyl cases), respectively. The corresponding (S)-cross-coupling products by V(O)-2 were obtained in 28–55% (for 2-substituted series) and 45–72% yields (for 1-substituted series) for the same substrate class in 50–91% ees (85–91% ees in 2-phenyl cases) and 64–75% ees (up to 74–75% ees for each 1-H, Ph, and Bn cases), respectively. Theoretical calculations were carried out to explain the origin and extent of enantiocontrols. They both may serve as potential inhibitors of acetohydroxyacid synthase and epidermal growth factor receptor (EGFR) kinases.

BackgroundThe proximal humerus fracture (PHF) is the third most common fragility fracture. Diabetes mellitus (DM) and chronic kidney disease (CKD) are both risks for fragility fractures; however, the interplay of DM and CKD makes treatment outcomes unpredictable. This study aimed to investigate and compare early and late outcomes following proximal humerus fracture fixation surgery in diabetic patients with different renal function conditions.MethodsDM patients receiving PHF fixation surgery during 1998-2013 were recruited from Taiwan's National Health Insurance Research Database. According to their renal function, patients were divided into three study groups: non-chronic kidney disease (CKD), non-dialysis CKD, and dialysis. Outcomes of interest were early and late perioperative outcomes. Early outcomes included in-hospital newly-onset morbidities. Late outcomes included infection, revision, readmission, and all-cause mortality.ResultsThis study included a total of 10,850 diabetic patients: 2152 had CKD (non-dialysis CKD group), 196 underwent permanent dialysis (dialysis group), and the remaining 8502 did not have CKD (non-CKD group). During a mean follow-up of 5.56 years, the dialysis group showed the highest risk of overall infection, all-cause revision, readmission, and mortality compared to the non-dialysis CKD group and non-CKD group. Furthermore, subgroup analysis showed that CKD patients had a higher risk of surgical infection following PHF surgery than non-CKD patients in cases with a traffic accident or fewer comorbidities (Charlson Comorbidity Index, CCI ConclusionCKD was associated with elevated risks for infection, revision, readmission, and mortality after PHF fixation surgery in diabetic patients. These findings should be taken into consideration when caring for diabetic patients.

Purpose: The purpose of this study is to investigate the influences of system and instructor factors on e-learning effectiveness under the interactions of computer self-efficacy. In this study, the factors of the e-learning system are functionality, interaction, and response. The factors of the e-learning instructor are attitude, technical skills, and instructional method. The moderating effects of learners' computer self-efficacy are examined. Design/methodology/approach: The study surveyed general employees in the financial services industry in Taiwan. A questionnaire was developed to measure participants' perceptions. Four hundred questionnaires were sent out, and 362 were returned. Of these, 314 were valid, leading to a return rate of 78.5 percent. Findings: The results of data analysis indicate that both system and instructor factors have significant positive influences on e-learning effectiveness. Learners' computer self-efficacy has a moderating effect on the relationship between system functionality and training effectiveness. The higher the computer self-efficacy, the stronger is the relationship between functionality and effectiveness, and vice versa. However, computer self-efficacy does not have a significant moderating effect on the relationship between other independent variables and training effectiveness. Originality/value: Since both system and instructor factors have positive influences on e-learning effectiveness, HRD managers need to pay more attention to issues in both areas. High computer self-efficacy can result in better training effectiveness; therefore, it is necessary to pay attention to enhancing employee computer skills and their confidence in using e-learning. (Contains 5 tables and 1 figure.)

Purpose: This study aims to explore the intercultural training needs for US business expatriates on assignment in Taiwan. The study assesses Taiwan culture-specific training needs of US expatriates from the perspectives of both US expatriates and their Taiwanese colleagues and compares the perceived importance of these intercultural training needs between these two groups. Design/methodology/approach: This study used the survey method to assess the opinions of US business expatriates as well as their Taiwanese colleagues. A questionnaire was developed for the study. A total of 26 items were identified as knowledge and skills needed for US business expatriates in Taiwan. The items all fall within six categories: knowledge of the nation, relationship building, interpersonal communication, business protocol, legal issues, and living in Taiwan. Findings: Data collected from 78 US respondents and 78 Taiwanese respondents were analyzed using matched pairs t-tests. Between-group differences for the overall 26 items and each category were examined. Results indicate that there was a significant difference between the US and Taiwanese respondents in the perceived importance of the overall items. Originality/value: Although there has been an abundance of literature on intercultural training, rarely has research been done on Taiwan cultural-specific training. A study in this area can help human resource practitioners in developing expatriate training programs. Research results can contribute to the knowledge base of expatriate training and development, as well as the development of theories in this area. (Contains 4 tables.)

BACKGROUND: Compound targeting histone deacetylase (HDAC) represents a new era in molecular cancer therapeutics. However, effective HDAC inhibitors for the treatment of solid tumors remain to be developed. METHODOLOGY/PRINCIPAL FINDINGS: Here, we propose a novel HDAC inhibitor, N-Hydroxy-4-(4-phenylbutyryl-amino) benzamide (HTPB), as a potential chemotherapeutic drug for solid tumors. The HDAC inhibition of HTPB was confirmed using HDAC activity assay. The antiproliferative and anti-migratory mechanisms of HTPB were investigated by cell proliferation, flow cytometry, DNA ladder, caspase activity, Rho activity, F-actin polymerization, and gelatin-zymography for matrix metalloproteinases (MMPs). Mice with tumor xenograft and experimental metastasis model were used to evaluate effects on tumor growth and metastasis. Our results indicated that HTPB was a pan-HDAC inhibitor in suppressing cell viability specifically of lung cancer cells but not of the normal lung cells. Upon HTPB treatment, cell cycle arrest was induced and subsequently led to mitochondria-mediated apoptosis. HTPB disrupted F-actin dynamics via downregulating RhoA activity. Moreover, HTPB inhibited activity of MMP2 and MMP9, reduced integrin-β1/focal adhesion complex formation and decreased pericellular poly-fibronectin assemblies. Finally, intraperitoneal injection or oral administration of HTPB efficiently inhibited A549 xenograft tumor growth in vivo without side effects. HTPB delayed lung metastasis of 4T1 mouse breast cancer cells. Acetylation of histone and non-histone proteins, induction of apoptotic-related proteins and de-phosphorylation of focal adhesion kinase were confirmed in treated mice. CONCLUSIONS/SIGNIFICANCE: These results suggested that intrinsic apoptotic pathway may involve in anti-tumor growth effects of HTPB in lung cancer cells. HTPB significantly suppresses tumor metastasis partly through inhibition of integrin-β1/FAK/MMP/RhoA/F-actin pathways. We have provided convincing preclinical evidence that HTPB is a potent HDAC targeted inhibitor and is thus a promising candidate for lung cancer chemotherapy.

BACKGROUND: Lung cancer is the leading cause of cancer mortality worldwide, yet the therapeutic strategy for advanced non-small cell lung cancer (NSCLC) is limitedly effective. In addition, validated histone deacetylase (HDAC) inhibitors for the treatment of solid tumors remain to be developed. Here, we propose a novel HDAC inhibitor, OSU-HDAC-44, as a chemotherapeutic drug for NSCLC. METHODOLOGY/PRINCIPAL FINDINGS: The cytotoxicity effect of OSU-HDAC-44 was examined in three human NSCLC cell lines including A549 (p53 wild-type), H1299 (p53 null), and CL1-1 (p53 mutant). The antiproliferative mechanisms of OSU-HDAC-44 were investigated by flow cytometric cell cycle analysis, apoptosis assays and genome-wide chromatin-immunoprecipitation-on-chip (ChIP-on-chip) analysis. Mice with established A549 tumor xenograft were treated with OSU-HDAC-44 or vehicle control and were used to evaluate effects on tumor growth, cytokinesis inhibition and apoptosis. OSU-HDAC-44 was a pan-HDAC inhibitor and exhibits 3-4 times more effectiveness than suberoylanilide hydroxamic acid (SAHA) in suppressing cell viability in various NSCLC cell lines. Upon OSU-HDAC-44 treatment, cytokinesis was inhibited and subsequently led to mitochondria-mediated apoptosis. The cytokinesis inhibition resulted from OSU-HDAC-44-mediated degradation of mitosis and cytokinesis regulators Auroroa B and survivin. The deregulation of F-actin dynamics induced by OSU-HDAC-44 was associated with reduction in RhoA activity resulting from srGAP1 induction. ChIP-on-chip analysis revealed that OSU-HDAC-44 induced chromatin loosening and facilitated transcription of genes involved in crucial signaling pathways such as apoptosis, axon guidance and protein ubiquitination. Finally, OSU-HDAC-44 efficiently inhibited A549 xenograft tumor growth and induced acetylation of histone and non-histone proteins and apoptosis in vivo. CONCLUSIONS/SIGNIFICANCE: OSU-HDAC-44 significantly suppresses tumor growth via induction of cytokinesis defect and intrinsic apoptosis in preclinical models of NSCLC. Our data provide compelling evidence that OSU-HDAC-44 is a potent HDAC targeted inhibitor and can be tested for NSCLC chemotherapy.

A diverse array of oxometallic species is examined as catalysts for a test direct condensation of benzoic acid and 2-phenylethanol and 1:1 stoichiometry. A new catalytic protocol is documented using an oxometallic type TiO(acac)2 as an efficient and chemoselective catalyst for the direct esterification between an equimolar amount of carboxylic acids and alcohols of varying steric and electronic demands in refluxed xylene.

Pulsed radiolysis experiments were performed on a series of bipolar OLED materials to determine their transient absorption and lifetime profiles of the independently in situ generated radical cations and anions in solutions. The findings for charge transporting behaviors within an OLED device which showed the relationship with transient absorption half-lives ([[tau].sub.1/2]) of the radical ions could be applied for molecular design of ideal bipolar optoelectronic materials.

The artificial, directed assembly process in chiral oxidovanadium(V) complex has allowed for the highly efficient [K.sup.+]- and [Ag.sup.+]-specific transport from aqueous phase containing other three alkali metal cations into organic solvents. The unique square pyramidal geometry for encapsulated [Ag.sup.+] is unprecedented and the acetonitrile ligand is present in a [C.sub.4]-symmetric environment created by the four flanking tert-butyl groups on the chiral oxidovanadium(V) templates.

The preparation of [C.sub.4]-symmetric penta-nuclear vanadyl(V) cluster bearing one central vanadate and four identical vanadyl 3,5-di-t-butyl N-salicyclene-L-t-leucimates as chiral peripheral units is reported.

A diverse array of oxometallic species were examined as catalysts in nucleophilic acyl substitution (NAS) reactions of methyl (or ethyl) esters with protic nucleophiles. The new NAS protocol is also amenable to amines and thiols in 74-91% yields, albeit with higher loading (2.4 equiv) of protic nucleophiles.

The acylations of protic neucleophiles including alcohols, amines, and thiols are important and commonly used transformations in organic synthesis. The resultant esters, amides, and thioesters constitute three major classes of carboxylic acid derivatives, serving as important functional components and/or intermediates in synthetic chemistry and biological systems.

Appending of two hole-transporting diarylamino segments onto both para positions of the cis-stilbene template in sky-blue fluorescent organic light emitting diode (OLED) materials which could be furnished with high EL brightness and working efficiencies is reported.

The first attempt of using doubly ortholinked quinoxaline/triarylamine 1:1 hybrid as a bifuctional, dipolar electrolumonecent clip is unraveled for bluish green and orange organic light emitting diodes applications. The 1:1 hybrid is potentially bipolar and may act as a central fluorescent of the C5- and C8-appendages.

A gallamide-containing pseudoenantiomeric helicene pair bearing a (10R,11R)-dimethoxymethyldibenzosuberane core can self-assemble by intermolecular amide H-bonding and π-π stacking into bundled helical fibers with helical tunnels of complementary helicity in CH2Cl2. The helicenes undergo excellent complementary photoswitchings of ternary logic at 280, 318, and 343 nm through (-)-gel-sol-(+)-gel interconversion. [ABSTRACT FROM AUTHOR]

Purpose – This study aims to focus on intercultural training for Taiwanese expatriates and assess the gap between intercultural training needs perceived by Taiwanese expatriates and the training provided by their companies.Design/methodology/approach – This study surveyed both Taiwanese expatriates and HR managers of their companies. It developed a questionnaire based on the research of Black and Mendenhall to assess contents and methods of intercultural training. There were 16 questions for assessing intercultural training and they were divided into two categories: symbolic learning and participatory learning.Findings – It is found that the needs of intercultural training perceived by expatriates are generally higher than the training provided by their companies. In the categories of symbolic and participatory learning, findings are consistent with the overall items. Results indicate that the perceived intercultural training needs of both categories are significantly higher than the training provided by their companies. Items of participatory learning are rated higher than those of symbolic learning by both groups.Originality/value – Coping with the increasing competition in the international arena, Taiwanese business people are in need of being able to work effectively with people from a diversity of countries and cultures. It is necessary to study issues related to intercultural training for business expatriates. Findings in this area can be helpful for human resource practitioners in developing training programs for their business expatriates. [ABSTRACT FROM AUTHOR]

Chiral oxidovanadium(V) methoxides prepared from 3,5-disubstituted-N-salicylidene-l-tert-butylglycines and vanadyl sulfate in air-saturated MeOH serve as highly enantioselective catalysts for asymmetric aerobic oxidations and kinetic resolution of alkyl, aryl, and heteroaryl α-hydroxy-ketones with differed α-substituents at ambient temperature in toluene or TBME (tert-butyl methyl ether). The best scenarios involve the use of complexes which bear the tridendate templates derived from 3,5-diphenyl- or 3-o-biphenyl-5-nitro-salicyaldehyde. The kinetic resolution selectivities of the aerobic oxidation process are in the range of 12 to >1000 based on the selectivity factors (krel). [ABSTRACT FROM AUTHOR]

A series of chiral vanadyl(V) methoxides bearing 3-t-butyl-5-substituted N-salicylene-L-valinate and L-t-leucinate as chiral auxiliaries has been prepared. In all cases except the 3,5-di-t-butyl analogue, they exist as monomers both in solution and in the single crystal state. In the case of the 3,5-di-t-butyl analogue, the architectural nature of the vanadyl(V) complex highly depends on the base used during the complex formation event. A pentanuclear C4-symmetric complex was formed when potassium salts were employed instead of the corresponding sodium salts. A central vanadate(V) unit serves to grip four identical chiral monomeric vanadyl(V) units together, by which a potassium ion sits on top of the four flanking units through carbonyl coordinations and serves to hold the whole cluster by cooperation with the central vanadate(V) unit. In comparison with the corresponding monomeric vanadyl(V) methoxide complex, the cluster complex was utilized to facilitate the asymmetric aerobic oxidations of various racemic α-hydroxyesters, -amides, and -thioesters with excellent selectivity factors (krel 40 to >500). [ABSTRACT FROM AUTHOR]

A series of chiral vanadyl carboxylates derived from N-salicylidene-ʟ-α-amino acids and vanadyl sulfate has been developed. These configurationally well defined complexes were examined for the kinetic resolution of double- and mono-activated 2° alcohols. The best chiral templates involve the combination of ʟ-tert-leucine and 3,5-di-t-butyl-, 3,5-diphenyl-, or 3,4-dibromo-salicylaldehyde. The resulting vanadyl(V)-methoxide complexes after recrystallization from air-saturated methanol serve as highly enantioselective catalysts for asymmetric aerobic oxidation of α-hydroxyl-esters and amides with a diverse array of α-, O-, and N-substituents at ambient temperature in toluene. The asymmetric inductions of the oxidation process are in the range of 10 to >100 in terms of selectivity factors (krel) in most instances. The previously undescribed aerobic oxidation protocol is also applicable to the kinetic resolution of C-13 taxol side chain with high selectivity factor (krel = 35). X-ray crystallographic analysis of an adduct between a given vanadyl complex and N-benzyl-mandelamide allows for probing the stereochemical origin of the nearly exclusive asymmetric control in the oxidation process. [ABSTRACT FROM AUTHOR]

Examines the synthesis of C2-symmetric (10R,11R)-diethyl substituted dibenzosuberane-based helicenes. Conversion into chirochromic optical switch; Desulfurization of the episulfides; Photoisomerization of the diastereomerically pure (10R,11R,P)-helicene.

A diverse array of oxometallic species were examined as catalysts for a test direct condensation of benzoic acid and 2-phenylethanol in 1:1 stoichiometry. Besides group IVB MOCl2-χH2O and TiOX2-χH2O, group VB VOCI2-χTHF and group IVB TiO(acac)2 were found to be the most efficient and water-tolerant catalysts for the test reaction. The new neutral catalytic protocol with the optimal TiO(acac)2 tolerates many stereo/electronic structural variations in both (di)-acid (1°–3° alky and aryl) and (di)alcohol (1°, 2° alkyl, and aryl) components with high chemoselectivity. [ABSTRACT FROM AUTHOR]

The article discusses the study which examines the directed assembly process in chiral oxidavanadium(V) methoxides into Carbon (C)4-symmetric metal(I) vanadate-centered quadruplexes. The study explores the artificial C4-symmetric oligonuclear assemblies in a synergistic mode. It shows that directed assembly in chiral oxidovanadium(V) complex allows highly efficient Phosphorus (K)+- and Gold (Ag)+-specific transport.

Presents the study on the development of a novel type nucleophile-tolerant triarylcarbeium chlorides based on the dibenzosuberane scaffold. Allylation reaction with minimal intervention of silyl catalysis; Effects of silyl promoters and templates on the trityl chloride-catalyzed allylations of benzaldehyde with allytri-n-butyltin.

A series of bipolar OLED materials were subjected to pulsed radiolysis experiments to determine their transient absorption and lifetime profiles of the independently in situ generated radical cations and anions in solutions. Moreover, their emission behaviors from the charge recombination of their radical ions were also determined by the pulse radiolysis method. It was found the absorption bands in doubly ortho- linked quinoxaline/diphenylfluorene hybrids la-e are red-shifted progressively with increasing electron- donating nature at the C5 and C8 positions of the quinoxaline template. The incipient radical anions in la-e are mainly localized on the quinoxaline heterocyclic moiety, whereas the incipient radical cations are mainly distributed onto the attached electron-donating groups at the C5 and C8 positions of the quinoxaline template. For other doubly ortho-linked cis-stilbene derivatives 3d, 3f, and 4f, the radical anions are mainly localized on the cis-stilbene central moiety and the radical cation is mainly distributed onto both para substituents of the cis-stilbene templates. It was also shown that there is a correlation between their optoelectronic emission efficiencies and the radiolysis induced emission intensities. In addition, the charge transporting behaviors within an OLED device were found to show the relationship with transient absorption half-lives (τ½) of the radical ions. Charge recombination mechanisms in both the OLED and pulsed radiolysis experiments were proposed to rationalize these observations, allowing us to establish some guidelines for an ultimate molecular design of ideal bipolar optoelectronic materials with a judicious choice of local charge appendages in the optoelectronic templates. [ABSTRACT FROM AUTHOR]

The article examines the feasibility of the direct asymmetric aerobic oxidation of a-hydroxyphosphonates at ambient temperature by chiral vanadyl complexes. The researchers applied a newly developed strategy unto the aerobic oxidation of a test dibenzyl phenylhydroxymethylphosphonate with varying C3- and C5-substituents in the N-salicylidene template of catalysts. A-hydroxyphosphonates have inhibitoary activities towards HIV protease and tyrosine specific kinase.