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1.
J Phys Chem A ; 128(16): 3220-3229, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38607425

RESUMO

We introduce projected-momentum covariance mapping, an extension of recoil-frame covariance mapping for 2D ion imaging studies. By considering the two-dimensional projection of the ion momenta as recorded by the detector, one opens the door to a complex suite of analysis tools adapted from three-dimensional momentum imaging studies. This includes the use of different frames of reference to unravel the dynamics of fragmentation and the application of fragment momentum constraints to isolate specific fragmentation channels. The technique is demonstrated on data from a two-dimensional ion imaging study of the Coulomb explosion of the cis and trans isomers of 1,2-dichloroethene, following strong-field ionization by an intense near-infrared femtosecond laser pulse. Classical simulations are used to guide the interpretation of projected-momentum covariance maps. The results offer a detailed insight into the distinct Coulomb explosion dynamics for this pair of isomers and lay the groundwork for future time-resolved studies of photoisomerization dynamics in this molecular system.

2.
J Phys Chem A ; 125(24): 5385-5396, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34121392

RESUMO

We present a composite procedure based on explicitly correlated CCSD(T)-F12 calculations for accurate energetic predictions for carbon chain molecules HCnH encompassing both the even (HC2kH) and odd series (HC2k-1H), with the shorter members playing a key role in the evolution of cosmic carbon compounds in both circumstellar envelopes and interstellar medium. This approach considers the contributions of core-valence correlation, scalar relativistic effect, spin-orbit coupling, and zero-point vibrational energy in an additive manner. The computed ionization energies demonstrate outstanding agreement (±0.07 eV) up to a chain size of k = 6 and the literature heats of formation for k ≤ 2 are reproduced with "chemical accuracy" of 1 kcal mol-1. Among the various corrections included, the importance of core-valence correlation effect has been highlighted in the thermochemical calculations for carbon chain growth. The thermochemical trend toward infinite length is also highlighted by extrapolation of ionization energy and triplet-singlet splitting at the CCSD(T) level for k up to 15. The correlation between the end-group effect and the even-odd parity effect observed for HCnH chains has been established with the aid of intrinsic bond orbital localization.

3.
J Phys Chem A ; 125(23): 4957-4966, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34076442

RESUMO

The ionization energies of VCH2 and VCH3, the various 0 K bond dissociation energies (D0s) in their neutrals and cations, and their respective heats of formation at 0 and 298 K are computed by the single-reference, wave function-based CCSDTQ/CBS procedure. The core of the composite method is the approximation to the complete basis set (CBS) limit at the coupled cluster (CC) level which includes up to full quadruple excitations. The zero-point vibrational energy, core-valence correlation, spin-orbit coupling, and scalar relativistic effects have their contributions incorporated in an additive manner. For the species in the current study, this protocol requires geometry optimizations and harmonic frequency calculations practically no higher than the CCSD(T)/aug-cc-pwCVTZ and CCSD(T)/aug-cc-pVTZ levels, respectively. The present calculations successfully predict D0(V+-CH3) = 2.126 eV and D0(V+-CH2) = 3.298 eV in remarkable agreement with the data recently measured by a spin-orbit state selected V+ + CH4 collision experiment (Phys. Chem. Chem. Phys. 2021, 23, 273-286). The good accord encourages the use of CCSDTQ/CBS protocol in thermochemical predictions of various feasible product channels identified in methane activation by transition metal species.

4.
Adm Policy Ment Health ; 47(1): 107-114, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31617138

RESUMO

To investigate the effectiveness of the Clubhouse Model of Psychosocial Rehabilitation on psychosocial functions and recovery of native Chinese individuals with schizophrenia in a community sample. A randomized controlled design was used. A total of 56 participants were recruited from a community sample for a study lasting 6 months, but five participants dropped out. Twenty-eight participants attended the Clubhouse program, and twenty-three participants served as controls. Standardized assessments were performed on three areas at the baseline and the 6-month follow-up: 1. symptom reduction; 2. social function, self-determination, and quality of life; and 3. rehospitalization rate. Compared to the controls, the Clubhouse participants showed reductions in psychiatric symptoms and better social function, self-determination, and quality of life (p < .05), but with no difference in the rehospitalization rate between Clubhouse members and the controls. The Clubhouse Model demonstrates its effectiveness and shows its viability as a service delivery model in psychosocial rehabilitation for individuals with schizophrenia in mainland China.


Assuntos
Reabilitação Psiquiátrica/organização & administração , Esquizofrenia/reabilitação , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Autonomia Pessoal , Qualidade de Vida , Índice de Gravidade de Doença , Ajustamento Social , Fatores Socioeconômicos
5.
J Phys Chem A ; 123(34): 7454-7462, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31414807

RESUMO

The ionization energy (IE) of VCH, the 0 K V-CH/VC-H bond dissociation energies (D0s), and the heats of formation at 0 K (ΔHf0°) and 298 K (ΔHf298°) for VCH/VCH+ are predicted by the wave function-based CCSDTQ/CBS approach. This composite-coupled cluster method includes full quadruple excitations in conjunction with the approximation to the complete basis set (CBS) limit. The contributions of zero-point vibrational energy, core-valence (CV) correlation, spin-orbit coupling, and scalar relativistic corrections are taken into account. The present calculations show that adiabatic IE(VCH) = 6.785 eV and demonstrate excellent agreement with an IE value of 6.774 7 ± 0.000 1 eV measured with two-color laser-pulsed field ionization-photoelectron spectroscopy. The CCSDT and MRCI+Q methods which include CV correlations give the best predictions of harmonic frequencies: ω2 (ω2+) (bending) = 534 (650) and 564 (641) cm-1 and the V-CH stretching ω3 (ω3+) = 835 (827) and 856 (857) cm-1 compared with the experimental values. In this work, we offer a streamlined CCSDTQ/CBS approach which shows an error limit (≤20 meV) matching with previous benchmarking efforts for reliable IE and D0 predictions for VCH/VCH+. The CCSDTQ/CBS D0(V+-CH) - D0(V-CH) = -0.012 eV and D0(VC+-H) - D0(VC-H) = 0.345 eV are in good accord with the experimentally derived values of -0.028 4 ± 0.000 1 and 0.355 9 ± 0.000 1 eV, respectively. The present study has demonstrated that the CCSDTQ/CBS protocol can be readily extended to investigate triatomic molecules containing 3d-metals.

6.
J Phys Chem A ; 120(16): 2521-36, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-27091706

RESUMO

We investigate the unimolecular dissociation of the vinoxy radical (CH2CHO) prepared with high internal energy imparted from the photodissociation of chloroacetaldehyde (CH2ClCHO) at 157 nm. Using a velocity map imaging apparatus, we measured the speed distribution of the recoiling chlorine atoms, Cl((2)P3/2) and Cl((2)P1/2), and derived from this the resulting distribution of kinetic energy, P(ET), imparted to the Cl + vinoxy fragments upon dissociation. Using conservation of energy, the distribution of kinetic energy was used to determine the total internal energy distribution in the radical. The P(ET) derived for the C-Cl bond fission presented in this work suggests the vinoxy radicals are mostly formed in the à state. We also took ion images at m/z = 42 and m/z = 15 to characterize the branching between the unimolecular dissociation channels of the vinoxy radical to H + ketene and methyl + CO products. Our results show a marked change in the branching ratio between the two channels from the previous study on the photodissociation of chloroacetaldehyde at 193 nm by Miller et al. (J. Chem. Phys., 2004, 121, 1830) in that the production of ketene is now favored over the production of methyl. To help analyze the data, we developed a model for the branching between the two channels that takes into account how the change in rotational energy en route to the products affects the vibrational energy available to surmount the barriers to the channels. The model predicts the portion of the C-Cl bond fission P(ET) that produces dissociative vinoxy radicals, then predicts the branching ratio between the H + ketene and CH3 + CO product channels at each ET. The model uses Rice-Ramsperger-Kassel-Marcus rate constants at the correct sums and densities of vibrational states while accounting for angular momentum conservation. We find that the predicted portion of the P(ET) that produces H + ketene products best fits the experimental portion (that we derive by taking advantage of conservation of momentum) if we use a barrier height for the H + ketene channel that is 4.0 ± 0.5 kcal/mol higher than the isomerization barrier en route to CH3 + CO products. Using the G4 computed isomerization barrier of 40.6 kcal/mol, this gives an experimentally determined barrier to the H + ketene channel of 44.6 kcal/mol. From these calculations, we also predict the branching ratio between the H + ketene and methyl + CO channels to be ∼2.1:1.

7.
J Phys Chem A ; 118(2): 404-16, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24392709

RESUMO

We report a study of the unimolecular dissociation of BrCH2CH2O radicals produced from the photodissociation of BrCH2CH2ONO at 351/355 nm. Using both a crossed laser-molecular beam scattering apparatus with electron bombardment detection and a velocity map imaging apparatus with tunable VUV photoionization detection, we investigate the initial photodissociation channels of the BrCH2CH2ONO precursor and the subsequent dissociation of the vibrationally excited BrCH2CH2O radicals. The only photodissociation channel of the precursor we detected upon photodissociation at 351 nm was O-NO bond fission. C-Br photofission and HBr photoelimination do not compete significantly with O-NO photofission at this excitation wavelength. The measured O-NO photofission recoil kinetic energy distribution peaks near 14 kcal/mol and extends from 5 to 24 kcal/mol. There is also a small signal from lower kinetic energy NO product (it would be 6% of the total if it were also from O-NO photofission). We use the O-NO photofission P(ET) peaking near 14 kcal/mol to help characterize the internal energy distribution in the nascent ground electronic state BrCH2CH2O radicals. At 351 nm, some but not all of the BrCH2CH2O radicals are formed with enough internal energy to unimolecularly dissociate to CH2Br + H2CO. Although the signal at m/e = 93 (CH2Br(+)) obtained with electron bombardment detection includes signal both from the CH2Br product and from dissociative ionization of the energetically stable BrCH2CH2O radicals, we were able to isolate the signal from CH2Br product alone using tunable VUV photoionization detection at 8.78 eV. We also sought to investigate the source of vinoxy radicals detected in spectroscopic experiments by Miller and co-workers ( J. Phys. Chem. A 2012 , 116 , 12032 ) from the photodissociation of BrCH2CH2ONO at 351 nm. Using velocity map imaging and photodissociating the precursor at 355 nm, we detected a tiny signal at m/e = 43 and a larger signal at m/e = 15 that we tentatively assign to vinoxy. An underlying signal in the time-of-flight spectra at m/e = 29 and m/e = 42, the two strongest peaks in the literature electron bombardment mass spectrum of vinoxy, is also apparent. Comparison of those signal strengths with the signal at HBr(+), however, shows that the vinoxy product does not have HBr as a cofragment, so the prior suggestion by Miller and co-workers that the vinoxy might result from a roaming mechanism is contraindicated.

8.
J Phys Chem A ; 117(39): 9531-47, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23496411

RESUMO

These experiments photolytically generate two key intermediates in the decomposition mechanisms of energetic materials with nitro substituents, 2-nitropropene, and 2-nitro-2-propyl radicals. These intermediates are produced at high internal energies and access a number of competing unimolecular dissociation channels investigated herein. We use a combination of crossed laser-molecular beam scattering and velocity map imaging to study the photodissociation of 2-bromo-2-nitropropane at 193 nm and the subsequent unimolecular dissociation of the intermediates above. Our results demonstrate that 2-bromo-2-nitropropane has four primary photodissociation pathways: C-Br bond fission yielding the 2-nitro-2-propyl radical, HBr elimination yielding 2-nitropropene, C-N bond fission yielding the 2-bromo-2-propyl radical, and HONO elimination yielding 2-bromopropene. The photofragments are formed with significant internal energy and undergo many secondary dissociation events, including the exothermic dissociation of 2-nitro-2-propyl radicals to NO + acetone. Calculations at the G4//B3LYP/6-311++g(3df,2p) level show that the presence of a radical at a nitroalkyl center changes the mechanism for and substantially lowers the barrier to NO loss. This mechanism involves an intermediate with a three-center ring rather than the intermediate formed during the traditional nitro-nitrite isomerization. The observed dissociation pathways of the 2-nitro-2-propyl radical and 2-nitropropene help elucidate the decomposition mechanism of larger energetic materials with geminal dinitro groups.

9.
J Chem Phys ; 138(9): 094301, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23485288

RESUMO

We have conducted a two-color visible-ultraviolet (VIS-UV) resonance-enhanced laser photoionization efficiency and pulsed field ionization-photoelectron (PFI-PE) study of gaseous cobalt carbide (CoC) near its ionization onset in the total energy range of 61,200-64,510 cm(-1). The cold gaseous CoC sample was prepared by a laser ablation supersonically cooled beam source. By exciting CoC molecules thus generated to single N' rotational levels of the intermediate CoC∗((2)Σ(+); v') state using a VIS dye laser prior to UV laser photoionization, we have obtained N(+) rotationally resolved PFI-PE spectra for the CoC(+)(X(1)Σ(+); v(+) = 0 and 1) ion vibrational bands free from interference by impurity species except Co atoms produced in the ablation source. The rotationally selected and resolved PFI-PE spectra have made possible unambiguous rotational assignments, yielding accurate values for the adiabatic ionization energy of CoC(X(2)Σ(+)), IE(CoC) = 62,384.3 ± 0.6 cm(-1) (7.73467 ± 0.00007 eV), the vibrational frequency ωe (+) = 985.6 ± 0.6 cm(-1), the anharmonicity constant ωe (+)χe (+) = 6.3 ± 0.6 cm(-1), the rotational constants (Be (+) = 0.7196 ± 0.0005 cm(-1), αe (+) = 0.0056 ± 0.0008 cm(-1)), and the equilibrium bond length re (+) = 1.534 Å for CoC(+)(X(1)Σ(+)). The observation of the N(+) = 0 level in the PFI-PE measurement indicates that the CoC(+) ground state is of (1)Σ(+) symmetry. Large ΔN(+) = N(+) - N' changes up to 6 are observed for the photoionization transitions CoC(+)(X(1)Σ(+); v(+) = 0-2; N(+)) ← CoC∗((2)Σ(+); v'; N' = 6, 7, 8, and 9). The highly precise energetic and spectroscopic data obtained in the present study have served as a benchmark for testing theoretical predictions based on state-of-the-art ab initio quantum calculations at the CCSDTQ∕CBS level of theory as presented in the companion article.


Assuntos
Compostos Inorgânicos de Carbono/química , Cobalto/química , Cor , Lasers , Cátions/química , Processos Fotoquímicos
10.
J Chem Phys ; 138(9): 094302, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23485289

RESUMO

The ionization energy (IE) of CoC and the 0 K bond dissociation energies (D0) and the heats of formation at 0 K (ΔH°f0) and 298 K (ΔH°f298) for CoC and CoC(+) are predicted by the wavefunction based coupled-cluster theory with single, double, triple and quadruple excitations (CCSDTQ) and complete basis set (CBS) approach. The CCSDTQ∕CBS calculations presented here involve the approximation to the CBS limit at the coupled cluster level up to full quadruple excitations along with the zero-point vibrational energy, high-order correlation, core-valence (CV) electronic, spin-orbit coupling, and scalar relativistic effect corrections. The present calculations provide the correct symmetry, (1)Σ(+), for the ground state of CoC(+). The CCSDTQ∕CBS IE(CoC) = 7.740 eV is found in good agreement with the experimental IE value of 7.73467 ± 0.00007 eV, determined in a two-color laser photoion and pulsed field ionization-photoelectron study. This work together with the previous experimental and theoretical investigations support the conclusion that the CCSDTQ∕CBS method is capable of providing reliable IE predictions for 3d-transition metal carbides, such as FeC, CoC, and NiC. Among the single-reference based coupled-cluster methods and multi-reference configuration interaction (MRCI) approach, the CCSDTQ and MRCI methods give the best predictions to the harmonic frequencies ωe (ωe (+)) = 956 (992) and 976 (1004) cm(-1) and the bond lengths re (re (+)) = 1.560 (1.528) and 1.550 (1.522) Å, respectively, for CoC (CoC(+)) in comparison with the experimental values. The CCSDTQ∕CBS calculations give the prediction of D0(Co(+)-C) - D0(Co-C) = 0.175 eV, which is also consistent with the experimental determination of 0.14630 ± 0.00014 eV. The theoretical results show that the CV and valence-valence electronic correlations beyond CCSD(T) wavefunction and the relativistic effect make significant contributions to the calculated thermochemical properties of CoC∕CoC(+). For the experimental D0 and ΔH(o) f0 values of CoC∕CoC(+), which are not known experimentally, we recommend the following CCSDTQ∕CBS predictions: ΔH(o) f0(CoC) = 775.7 kJ∕mol and ΔH(o) f0(CoC(+)) = 1522.5 kJ∕mol, ΔH(o) f298(CoC) = 779.2 kJ∕mol and ΔH(o) 298(CoC(+)) = 1526.0 kJ∕mol.


Assuntos
Compostos Inorgânicos de Carbono/química , Cobalto/química , Temperatura Alta , Teoria Quântica , Cátions/química
11.
Brain Inj ; 27(9): 1016-25, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23662639

RESUMO

BACKGROUND: People with traumatic brain injury (TBI) often experience cognitive deficits in attention, memory, executive functioning and problem-solving. The purpose of the present research study was to examine the effectiveness of an artificial intelligent virtual reality (VR)-based vocational problem-solving skill training programme designed to enhance employment opportunities for people with TBI. METHOD: This was a prospective randomized controlled trial (RCT) comparing the effectiveness of the above programme with that of the conventional psycho-educational approach. Forty participants with mild (n = 20) or moderate (n = 20) brain injury were randomly assigned to each training programme. Comparisons of problem-solving skills were performed with the Wisconsin Card Sorting Test, the Tower of London Test and the Vocational Cognitive Rating Scale. RESULTS: Improvement in selective memory processes and perception of memory function were found. Across-group comparison showed that the VR group performed more favourably than the therapist-led one in terms of objective and subjective outcome measures and better vocational outcomes. CONCLUSIONS: These results support the potential use of a VR-based approach in memory training in people with MCI. Further VR applications, limitations and future research are described.


Assuntos
Lesões Encefálicas/reabilitação , Transtornos Cognitivos/reabilitação , Emprego , Reabilitação Vocacional , Terapia de Exposição à Realidade Virtual , Adolescente , Adulto , Lesões Encefálicas/epidemiologia , Lesões Encefálicas/psicologia , China/epidemiologia , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/psicologia , Função Executiva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resolução de Problemas , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Resultado do Tratamento
12.
Int J Psychiatry Clin Pract ; 16(4): 284-92, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22217497

RESUMO

OBJECTIVE: A large-scale quantitative study was conducted by stratified representative samples from Chicago (prototype of the United States; N = 293), Beijing (prototype of urbanized China; N = 302), and Hong Kong (prototype of East-meets-West culture; N = 284) to explore factors that might lead to their stigmatizing attitudes towards hiring individuals with (mental illness, alcohol abuse, drug abuse, and HIV/AIDS) and without (bone cancer) behavioral-driven health conditions. METHODS: Consented employers completed the Employer Survey pertaining to their attitudes towards specific health conditions, previous hiring experiences, resources, assets of applicants, and hiring concerns. RESULTS: The findings suggested that employers in Hong Kong and Beijing were more willing to hire individuals with alcohol abuse, whereas employers in Chicago were more willing to hire those with HIV/AIDS or bone cancer. Logistic regression suggested that the type of health conditions, assets of applicants, and perceived level of dangerousness of applicants were significant predictors that contributed to employers' hiring preference. CONCLUSION: Employers express different hiring preference towards individuals with or without behavioral-driven health conditions. Their hiring preference towards specific type of health conditions is discussed.


Assuntos
Atitude Frente a Saúde , Emprego/psicologia , Transtornos Mentais/psicologia , Seleção de Pessoal/estatística & dados numéricos , Estereotipagem , Neoplasias Ósseas/psicologia , Chicago , China , Cultura , Emprego/estatística & dados numéricos , Feminino , Infecções por HIV/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação Pessoal , Análise de Regressão
13.
J Chem Phys ; 134(14): 144304, 2011 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-21495752

RESUMO

Vacuum ultraviolet (VUV) laser pulsed field ionization-photoelectron (PFI-PE) spectroscopy has been applied to the study of the sulfur monoxide radical (SO) prepared by using a supersonically cooled radical beam source based on the 193 nm excimer laser photodissociation of SO(2). The vibronic VUV-PFI-PE bands for the photoionization transitions SO(+)(X(2)Π(1∕2); v(+) = 0) ← SO(X(3)Σ(-); v = 0); and SO(+)((2)Π(3∕2); v(+) = 0) ← SO(X(3)Σ(-); v = 0) have been recorded. On the basis of the semiempirical simulation of rotational branch contours observed in these PFI-PE bands, we have obtained highly precise ionization energies (IEs) of 83,034.2 ± 1.7 cm(-1) (10.2949 ± 0.0002 eV) and 83,400.4 ± 1.7 cm(-1) (10.3403 ± 0.0002 eV) for the formation of SO(+)(X(2)Π(1∕2); v(+) = 0) and SO(+)((2)Π(3∕2); v(+) = 0), respectively. The present VUV-PFI-PE measurement has enabled the direct determination of the spin-orbit coupling constant (A(0)) for SO(+)(X(2)Π(1∕2,3∕2)) to be 365.36 ± 0.12 cm(-1). We have also performed high-level ab initio quantum chemical calculations at the coupled-cluster level up to full quadruple excitations and complete basis set (CBS) extrapolation. The zero-point vibrational energy correction, the core-valence electronic correction, the spin-orbit coupling, and the high-level correction are included in the calculation. The IE[SO(+)(X(2)Π(1∕2,3∕2))] and A(0) predictions thus obtained are found to be in remarkable agreement with the experimental determinations.

14.
J Chem Phys ; 135(22): 224304, 2011 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-22168691

RESUMO

By employing the vacuum ultraviolet (VUV) laser velocity-map imaging (VMI) photoelectron scheme to discriminate energetic photoelectrons, we have measured the VUV-VMI-threshold photoelectrons (VUV-VMI-TPE) spectra of propargyl radical [C(3)H(3)(X̃(2)B(1))] near its ionization threshold at photoelectron energy bandwidths of 3 and 7 cm(-1) (full-width at half-maximum, FWHM). The simulation of the VUV-VMI-TPE spectra thus obtained, along with the Stark shift correction, has allowed the determination of a precise value 70 156 ± 4 cm(-1) (8.6982 ± 0.0005 eV) for the ionization energy (IE) of C(3)H(3). In the present VMI-TPE experiment, the Stark shift correction is determined by comparing the VUV-VMI-TPE and VUV laser pulsed field ionization-photoelectron (VUV-PFI-PE) spectra for the origin band of the photoelectron spectrum of the X̃(+)-X̃ transition of chlorobenzene. The fact that the FWHMs for this origin band observed using the VUV-VMI-TPE and VUV-PFI-PE methods are nearly the same indicates that the energy resolutions achieved in the VUV-VMI-TPE and VUV-PFI-PE measurements are comparable. The IE(C(3)H(3)) value obtained based on the VUV-VMI-TPE measurement is consistent with the value determined by the VUV laser PIE spectrum of supersonically cooled C(3)H(3)(X̃(2)B(1)) radicals, which is also reported in this article.

15.
Front Psychiatry ; 12: 691765, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630174

RESUMO

Background: This study examines changes over time in post-traumatic stress disorder (PTSD) among children who survived the 2008 Wenchuan earthquake and the relevant predictive variables. Methods: A total of 203 children and adolescents were investigated 24 months after the earthquake, and 151 children and adolescents completed the 1-year follow-up study. Participants completed the Children's Revised Impact of Event Scale (CRIES-13), the Center for Epidemiologic Studies Depression Scale (CES-D) and the Connor-Davidson Resilience Scale (CD-RISC). Hierarchical linear regression analysis was used to evaluate the predictors of changes in PTSD severity. Results: Eighty percent of the children still had some PTSD symptoms 2 years after the Wenchuan earthquake, and 66.25% of the children had symptoms that lasted 3 years. In the model predicting PTSD symptom severity, the loss of family members and child burial explained a significant 21.9% of the variance, and depression explained a significant 16.7% of the variance. In the model predicting changes in PTSD severity, the change scores for resilience and depression explained a significant 18.7% of the variance, and cognitive behavioral therapy (CBT) explained a significant 33.6% of the variance. Conclusions: PTSD symptoms in children and adolescents can persist for many years after trauma. In addition to using psychological interventions to improve PTSD symptoms, improvements in depression and resilience should also be considered.

16.
Front Psychiatry ; 12: 671217, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867500

RESUMO

Background: Community psychiatric rehabilitation has proven effective in supporting individuals and their families in recovering from mental illness. The delivery of evidence-based community rehabilitation services, however, requires health care workers to possess a set of specially trained knowledge and skills. Most developing countries, including China, do not have specially trained mental health personnel. The purpose of this study was to test the feasibility and efficacy of a community psychiatric rehabilitation program delivered by laypeople. Method: We conducted a randomized controlled study. Patients at two sites in Chengdu, China, were randomly assigned to either the laypeople-delivered (LPD) community psychiatric rehabilitation group (N = 49) or the drop-in center control group (N = 45). The outcomes were changes in symptoms, social functioning, and family functioning over 6 months, as measured by the Positive and Negative Syndrome Scale (PANSS), the Personal and Social Performance Scale (PSP), the Family Burden Scale of Disease (FBS), and the Family APGAR index. Results: The number of sessions received over the 12-week period of treatment ranged from 20 to 100%, with a mean completion rate of 77.32% for all 12 sessions. Statistically significant interactions between group and time were found for the total PANSS [F (2, 94) = 12.51, p < 0.001] and both the Negative PANSS [F (2, 94) = 5.89, p < 0.01] and Positive PANSS [F (2, 94) = 6.65, p < 0.01] as well as the PSP [F (2, 94) = 3.34, p < 0.05], FBS [F (2, 94) = 5.10, p < 0.01], and Family APGAR index [F (2, 94) = 4.58, p < 0.01]. The results showed that the experimental group outperformed their counterparts in symptom management, personal social functioning, family care burden, and coherence. Conclusion: These results support the feasibility and efficacy of having laypeople deliver psychiatric rehabilitation services. A discussion and limitations of the study have been included.

17.
Polymers (Basel) ; 13(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771229

RESUMO

A new mechanochemical method was developed to convert polymer wastes, polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC), to fuel gases (H2, CH4, and CO) under ball-milling with KMnO4 at room temperature. By using various solid-state characterizations (XPS, SEM, EDS, FTIR, and NMR), and density functional theory calculations, it was found that the activation followed the hydrogen atom transfer (HAT) mechanism. Two metal oxidant molecules were found to abstract two separate hydrogen atoms from the α-CH and ß-CH units of substrates, [-ßCH2-αCH(R)-]n, where R = H in PE, R = γCH3 in PP, and R = Cl in PVC, resulting in a di-radical, [-ßCH•-αC•(R)-]. Subsequently, the two unpaired electrons of the di-radical were recombined into an alkene intermediate, [-ßCH = αC(R)-], which underwent further oxidation to produce H2, CH4, and CO gases.

18.
J Phys Chem Lett ; 12(24): 5789-5795, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34137607

RESUMO

Hydrogen- or proton-migration-induced isomerization has recently been of concern for its critical role in the dissociation of organic molecules of astrophysical or biological relevance. Herein we present a combined experimental and theoretical study of the two-body C-C bond breakdown dissociation of ethane dication. For the asymmetric fragmentation channel CH2+ + CH4+, the kinetic energy release measurements and ab initio quantum chemical calculations demonstrate that the reaction pathway involving hydrogen-migration-induced isomerization of [CH3-CH3]2+ to [CH2-CH4]2+ can be accessed via the lowest triplet state rather than the ground singlet state of ethane dication. Interestingly, it is found that a considerable proportion of the yield of symmetric fragmentation CH3+ + CH3+, which is usually considered from a direct Coulomb explosion and seemingly independent of isomerization, could come from the dissociation of ethane dication in the ground singlet state with the involvement of [CH3-CH3]2+ isomerization to intermediate [H2C(H2)CH2]2+ of the diborane-like double-bridged structure.

19.
J Nerv Ment Dis ; 198(2): 137-43, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20145489

RESUMO

We examine the degree of social support and quality of life (QOL) among 60 Latinos with mental illness from a Community Mental Health Center of a large metropolitan Midwestern city. Additionally, we assess the relationship of both the quality and quantity of social support, and control for demographic factors as they all relate to QOL. Latinos had an average network of 3 contacts. Despite their small network, participants were satisfied with the quality of support they received. Their QOL was mixed, comparable to reports from non-Latinos with mental illness, and from the general population. Having better quality of social support being male and younger were associated with a higher QOL. Community treatment programs for Latinos with mental illness could benefit from focusing on nurturing existing networks, fostering social skills, and providing additional forms of support for those Latinos in need.


Assuntos
Serviços Comunitários de Saúde Mental/provisão & distribuição , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , Transtornos Mentais/etnologia , Transtornos Mentais/terapia , Qualidade de Vida/psicologia , Apoio Social , Aculturação , Adulto , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Prevalência , Índice de Gravidade de Doença , Estados Unidos/epidemiologia
20.
Obes Surg ; 19(4): 422-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18516655

RESUMO

BACKGROUND: This study examined differences in gastric bypass surgical outcomes by comparing two groups of female patients: those with a history of sexual abuse (SA) and those without a history of sexual abuse (NSA). METHODS: Participants who agreed to participate in the study were assessed at either 6-18 months or 19-40 months postsurgery. Outcome measures included body mass index (BMI), level of depression as measured through the Beck Depression Inventory, level of self-esteem as measured through the Rosenberg Self-esteem Scale, and BISS as measured through the Body Image State Scale. Two-by-two analyses of variance (ANOVAs) were conducted for each of the four outcome variables. RESULTS: ANOVA results revealed that BMI was the only variable to be found statistically significant among the four dependent measures. At 6-18 months postsurgery, the SA group had significantly higher BMI than the NSA group. Compared BMI during the two postsurgery time periods, the SA group had a significantly lower BMI at 19-40 months than the SA group at 6-18 months postsurgery. CONCLUSION: The results suggest that females with a history of sexual abuse did not differ from their counterparts with regard to depression, self-esteem, and body dissatisfaction at baseline, as well as years after surgery. Given the improvement in BMI from the sexual abuse group at 6-18 months postsurgery to 19-40 month postsurgery, patients may not be as concerned with maintaining excess weight as a defense against potential future abuse as originally proposed.


Assuntos
Derivação Gástrica , Obesidade Mórbida/epidemiologia , Delitos Sexuais/estatística & dados numéricos , Adulto , Imagem Corporal , Índice de Massa Corporal , Estudos Transversais , Feminino , Derivação Gástrica/psicologia , Humanos , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Autoimagem , Delitos Sexuais/psicologia
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