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1.
Struct Dyn ; 6(6): 064303, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31832487

ABSTRACT

Most chemical and biochemical reactions in nature and in industrial processes are driven by thermal effects that bring the reactants above the energy barrier for reaction. In aqueous solutions, this process can also be triggered by the laser driven temperature jump (T-jump) method, in which the water vibrational (stretch, bend, or combination) modes are excited by a short laser pulse, leading to a temperature increase in the irradiated volume within a few picoseconds. The combination of the laser T-jump with X-ray spectroscopic probes would add element-specificity as well as sensitivity to the structure, the oxidation state, and the spin state of the intermediates of reactions. Here, we present preliminary results of a near infrared pump/X-ray absorption spectroscopy probe to study the ligand exchange of an octahedral aqueous Cobalt complex, which is known to pass through intermediate steps yielding tetrahedral chlorinated as final species. The structural changes of the chemical reaction are monitored with great sensitivity, even in the presence of a mild local increase in temperature. This work opens perspectives for the study of non-light-driven reactions using time-resolved X-ray spectroscopic methods.

2.
Phys Chem Chem Phys ; 19(43): 29271-29277, 2017 Nov 08.
Article in English | MEDLINE | ID: mdl-29067360

ABSTRACT

The potential of valence to core Al X-ray emission spectroscopy to determine aluminum distribution in ferrierite zeolites was investigated. The recorded emission spectra of four samples prepared with different structure directing agents exhibit slight variations in the position of the main emission peak and the intensity of its low energy shoulder. Theoretical calculations indicate that an increased intensity of the Kßx shoulder in the Al emission spectra can be linked to a predominant occupation of the T3 site by a single aluminum atom. This study thus suggests that valence to core X-ray emission spectroscopy can be applied to help determine the occupation of aluminum at crystallographic T-sites in zeolites.

3.
J Chem Phys ; 144(13): 134309, 2016 Apr 07.
Article in English | MEDLINE | ID: mdl-27059572

ABSTRACT

We present a theoretical and experimental study of resonant inelastic x-ray scattering on a large group of chlorinated hydrocarbons: CH3Cl, CH2Cl2, CHCl3, CCl4, CH3CH2Cl, ClCH2CH2Cl, CH3CHCl2, CH3CCl3, C2H2Cl2-iso, C2H2Cl2-cis, C2H2Cl2-trans, and C6H5Cl. Differences in structural and dynamical properties of the molecules generated by diverse chemical environments are observed in the measured Cl(K(α)) spectral maps as well as in the Cl(K) total fluorescence yield spectra. The energy position, relative intensity, and the width of the Franck-Condon distribution of low-lying σ* and π* resonances are extracted by a fitting procedure taking into account the experimental broadening. The theoretical values obtained with the transition potential and Δ Kohn-Sham methods are in good agreement with the experimental parameters indicating subtle differences due to variations in the molecular structure.

6.
South Med J ; 108(2): 79-81, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25688891

ABSTRACT

OBJECTIVES: The relation between elevated body mass index (BMI)/overweight-obesity and compliance with health care remains unclear; some studies have demonstrated a relation whereas others have not. To add to the confusion, a number of studies have examined specialized populations (eg, patients with diabetes mellitus) and/or only one parameter of compliance (eg, taking medication). In the present study, we examined primary care outpatients for relations between BMI and multiple parameters of healthcare adherence/compliance. METHODS: Using a cross-sectional approach and a self-report survey methodology, we examined 250 primary care outpatients using three measures of healthcare compliance: conscientiousness in following through with medical treatment; a 5-item questionnaire examining compliance with general healthcare behaviors such as regular dental checkups and arrival to doctors' appointments on time; and the Medical Outcomes Study General Adherence Items, a general measure of compliance with physician directives. RESULTS: With the exceptions of regular dental checkups, on-time arrival for doctors' appointments, and timely completion of laboratory work, the remaining variables demonstrated statistical significance at minimally the P & 0.05 level. CONCLUSIONS: Patients with higher BMIs self-report less willingness to adhere to general healthcare requests/recommendations than patients with lower BMIs.


Subject(s)
General Practice , Obesity/epidemiology , Outpatients/statistics & numerical data , Patient Compliance/statistics & numerical data , Self Report , Adolescent , Adult , Aged , Aged, 80 and over , Body Height , Body Mass Index , Body Weight , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Overweight/epidemiology , Surveys and Questionnaires , United States/epidemiology
7.
Int J Soc Psychiatry ; 61(8): 725-8, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25599687

ABSTRACT

BACKGROUND: The relationship between childhood bullying and healthcare adherence in adulthood has been rarely studied, but one published study suggests that being bullied in childhood is related to lower healthcare adherence among adolescents. This previous study examined few adherence variables and was limited to youths. AIMS: In this study, we assessed five variables for childhood bullying as related to seven measures of healthcare adherence among a cohort of adult primary care outpatients. METHOD: Using a cross-sectional, self-report survey methodology in a sample of 263 consecutive internal medicine outpatients, we examined five aspects of bullying and seven aspects of adherence with general healthcare. RESULTS: Being a victim of bullying, type of bullying (emotional, physical), number of years bullied and number of bullies each evidenced no statistical relationships with healthcare adherence. However, being a bully demonstrated several statistical relationships with healthcare adherence, indicating less adherence to instructions provided by healthcare professionals. CONCLUSIONS: Despite all of the deleterious psychological and physical effects of being bullied in childhood, there was no evidence that non-adherence with healthcare in adulthood is one of them. In contrast, bullies evidenced several areas of reduced healthcare adherence.


Subject(s)
Adult Survivors of Child Abuse/psychology , Bullying , Patient Acceptance of Health Care/psychology , Adolescent , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Self Report , United States , Young Adult
8.
Int J Psychiatry Clin Pract ; 19(2): 132-6, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25410155

ABSTRACT

OBJECTIVES: The extant literature on borderline personality disorder (BPD) and compliance with mental health treatment contains conflicting findings. However, among those individuals with this type of personality dysfunction, reduced compliance with mental health treatment appears to be the predominant theme. To our knowledge, the relationship between BPD and compliance with general health care has not been studied. In addition, there is no prior study in this area examining a primary care population. METHODS: Using a cross-sectional survey methodology among a sample of internal medicine outpatients (N = 261), we assessed borderline personality symptoms with two self-report measures and general health care compliance or adherence with four self-report measures. RESULTS: With the exception of on-time arrival for doctor appointments, the remaining compliance variables demonstrated statistically significant relationships at the p < 0.01-0.001 levels, with borderline personality symptoms predicting reduced compliance (i.e., conscientiousness with medical treatment, regular dental check-ups, timely completion of laboratory work, following doctor's exercise and nutrition instructions, remembering to take medications, and Medical Outcomes Study General Adherence Score). CONCLUSIONS: Compared with participants without borderline personality symptoms, those participants with such symptoms in this study evidenced lower general health care compliance.


Subject(s)
Borderline Personality Disorder/psychology , Outpatients/psychology , Patient Compliance/psychology , Primary Health Care , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Humans , Internal Medicine , Male , Middle Aged , Young Adult
11.
J Chem Phys ; 140(16): 164304, 2014 Apr 28.
Article in English | MEDLINE | ID: mdl-24784267

ABSTRACT

A theoretical analysis of dissociation dynamics of chlorine K-σ(*) core-excited molecules is performed. The potential energy surfaces of HCl, Cl2, CH3Cl, CH2Cl2, CHCl3, CCl4, CFCl3, CF2Cl2, and CF3Cl are calculated along the normal vibrational modes of the ground electronic state yielding the widths of the corresponding Franck-Condon distributions. An insight into the potential energy surface of 1st σ(*) resonances shows that the initial dissociation dynamics of chloro(fluoro)methanes mainly involves the distancing of the carbon and the core-excited chlorine atom and is practically independent of other atoms in the molecule, which is in agreement with the recent experimental findings. The carbon atom pulls out the remaining three atoms shortly after piercing the three-atom plane resulting in a high vibrationally excited state of the fragment if the reconnection time is smaller than the lifetime of the L shell.

12.
Article in English | MEDLINE | ID: mdl-25834767

ABSTRACT

OBJECTIVE: Beyond the examination of medication compliance among individuals with substance abuse or human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), few studies have examined relationships between childhood trauma and health care compliance in adulthood-the focus of the present study. METHOD: Using a cross-sectional approach and a self-report survey methodology, we examined 5 types of childhood trauma (ie, witnessing violence, physical neglect, emotional abuse, physical abuse, sexual abuse) in relationship to 4 measures of general health care compliance (ie, self-rated general conscientiousness with medical treatment; 5 items pertaining to general health care compliance such as scheduling regular dental checkups, timely arrival for doctor's appointments, and timely completion of laboratory work; 2 medication compliance items; and the Medical Outcomes Study general adherence score) among a sample of adult primary care outpatients (N = 272). Data were collected in March 2014. RESULTS: According to findings, some health care adherence variables demonstrated relationships with the summed childhood trauma score, whereas others did not. It could be interpreted that the more subjective health care compliance variables (eg, self-rated conscientiousness with regard to medical treatment) demonstrated no relationship with a summed childhood trauma score, whereas the more objective health care compliance variables (eg, frequency of regular dental checkups, ability to remember to take all medications, Medical Outcomes Study general adherence score) did demonstrate statistically significant relationships with a summed childhood trauma score (most at P < .01). CONCLUSIONS: Patients with histories of childhood trauma demonstrate some deficits with health care compliance in comparison to those without childhood trauma. One interpretation is that the mistreated appear to believe that they are fairly compliant with health care treatment, but objective variables appear to suggest otherwise.

13.
J Chem Phys ; 139(13): 134302, 2013 Oct 07.
Article in English | MEDLINE | ID: mdl-24116563

ABSTRACT

The dissociation process following the Cl K-shell excitation to σ* resonances is studied by high resolution spectroscopy of resonant elastic and inelastic x-ray scattering on CH3Cl, CH2Cl2, CHCl3, and CCl4 molecules. Calculations employing the transition potential and Delta-Kohn-Sham DFT approach are in good agreement with the measured total fluorescence yield and show the presence of a second quasidegenerate group of states with σ* character above the lowest σ* unoccupied molecular orbital for molecules with more than one Cl atom. A bandwidth narrowing and a nonlinear dispersion behavior is extracted from the Kα spectral maps for both σ* resonances. The fitted data indicate that the widths of the Franck-Condon distributions for the first and second σ* resonances are comparable for all the molecules under study. In addition, an asymmetric broadening of the emission peaks is observed for resonant elastic x-ray scattering with zero detuning on both σ* resonances. This is attributed to the fast dissociation, transferring about 0.15 of the scattering probability into higher vibrational modes.

14.
Rev Sci Instrum ; 83(3): 033113, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22462912

ABSTRACT

A complete in-vacuum curved-crystal x-ray emission spectrometer in Johansson geometry has been constructed for a 2-6 keV energy range with sub natural line-width energy resolution. The spectrometer is designed to measure x-ray emission induced by photon and charged particle impact on solid and gaseous targets. It works with a relatively large x-ray source placed inside the Rowland circle and employs position sensitive detection of diffracted x-rays. Its compact modular design enables fast and easy installation at a synchrotron or particle accelerator beamline. The paper presents main characteristics of the spectrometer and illustrates its capabilities by showing few selected experimental examples.

15.
Ann Plast Surg ; 61(3): 337-44, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18724139

ABSTRACT

Platelet-rich plasma (PRP) is a common therapy for acceleration of maxillofacial and spinal fusion bone-graft healing. This study analyzes the therapeutic role of PRP during long-bone fracture healing evaluated Lewis rats. Following creation of unilateral open femur fractures, either 500 microL thrombin-activated PRP (PRP treated group) or 500 microL saline (control group) were applied once to the fracture site. Fracture healing was analyzed after 1 and 4 weeks. Following 4 weeks of fracture healing, radiographic analysis demonstrated higher callus to cortex width ratio (P < 0.05) in the PRP group (PRP: 1.65 +/- 0.06; control: 1.48 +/- 0.05). Three-point load bearing showed increased bone strength following PRP treatment (PRP: 60.85 +/- 6.06 Newton, control: 47.66 +/- 5.49 Newton). Fracture histology showed enhanced bone formation in the PRP group. Immunohistochemistry and Western-blotting demonstrated healing-associated changes in transforming growth factor (TGF)-beta1 and bone morphogenetic protein (BMP)-2. Our results suggest that PRP accelerates bone fracture healing of rat femurs via modulation of TGF-beta1 and BMP-2 growth factor expression.


Subject(s)
Femoral Fractures/physiopathology , Femoral Fractures/therapy , Fracture Healing/physiology , Platelet-Rich Plasma/metabolism , Analysis of Variance , Animals , Blood Transfusion , Bone Morphogenetic Protein 2 , Bone Morphogenetic Proteins/metabolism , Bony Callus/diagnostic imaging , Bony Callus/pathology , Femoral Fractures/diagnostic imaging , Femoral Fractures/pathology , Male , Radiography , Rats , Rats, Inbred Lew , Transforming Growth Factor beta/metabolism , Transforming Growth Factor beta1/metabolism , Weight-Bearing
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