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1.
Mater Sci Semicond Process ; 38: 278-289, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26085801

ABSTRACT

As an obvious candidate for a p-type dopant in ZnO, nitrogen remains elusive in this role. Nitrogen containing precursors are a potential means to incorporate nitrogen during MOCVD growth. One class of nitrogen-containing precursors are zinc acetate amines, yet, they have received little attention. The synthesis and single crystal X-ray structure of [Zn(acetate)2(en)], and the synthesis of [Zn(acetate)2(en)2], [Zn(acetate)2(benzylamine)2], [Zn(acetate)2(butylamine)2], [Zn(acetate)2(NH3)2], and [Zn(acetate)2(tris)2], where en = ethylenediamine and tris = (tris[hydroxymethyl]aminomethane) are reported. The compounds were characterized by thermogravimetric analysis and pyrolyzed in air and inert gas to yield ZnO. These compounds are useful single source precursors to ZnO bulk powders by alkali precipitation and ZnO thin films by spray pyrolysis. The amine bound to the zinc influences the ZnO crystal size and shape and acts as a nitrogen donor for preparing nitrogen-doped ZnO during alkali precipitation. Thin films of ZnO prepared by spray pyrolysis using the precursors had a (100) preferred orientation and measured n-type to intrinsic conductivity.

2.
Toxicol Appl Pharmacol ; 275(3): 257-64, 2014 Mar 15.
Article in English | MEDLINE | ID: mdl-24518925

ABSTRACT

BACKGROUND: Erionite has similar chemical and physical properties to amphibole asbestos, which induces autoantibodies in mice. Current exposures are occurring in North Dakota due to the use of erionite-contaminated gravel. While erionite is known to cause mesothelioma and other diseases associated with asbestos, there is little known about its effects on the immune system. OBJECTIVES: We performed this study to determine whether erionite evokes autoimmune reactions in mice. METHODS: Bone marrow derived macrophages (BMDM) were used to measure toxicity induced by erionite. Cytokine production by BMDM and splenocytes of C57BL/6 mice was examined by bead arrays and ELISA following exposure to erionite, amphiboles and chrysotile. Wild type C57BL/6 mice were exposed to saline, erionite, amphibole asbestos (Libby 6-Mix) or chrysotile through intratracheal instillations at equal mass (60µg/mouse). Seven months after exposure, sera were examined for anti-nuclear antibodies (ANA) and IL-17. Immunohistochemistry was used to detect immune complex deposition in the kidneys. RESULTS: Erionite and tremolite caused increased cytokine production belonging to the TH17 profile including IL-17, IL-6, TGF-ß, and TNF-α. The frequency of ANA was increased in mice treated with erionite or amphibole compared to saline-treated mice. IL-17 and TNF-α were elevated in the sera of mice treated with erionite. The frequency of immune complex deposition in the kidneys increased from 33% in saline-treated mice to 90% with erionite. CONCLUSIONS: These data demonstrate that both erionite and amphibole asbestos induce autoimmune responses in mice, suggesting a potential for adverse effects in exposed communities.


Subject(s)
Antibodies, Antinuclear/blood , Autoimmunity/drug effects , Interleukin-17/blood , Zeolites/toxicity , Animals , Antigen-Antibody Complex/metabolism , Asbestos, Amphibole/toxicity , Asbestos, Serpentine/toxicity , Biomarkers/blood , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Female , Inhalation Exposure , Kidney/drug effects , Kidney/immunology , Kidney/metabolism , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Mice , Mice, Inbred C57BL , Spleen/drug effects , Spleen/immunology , Spleen/metabolism , Th1 Cells/drug effects , Th1 Cells/immunology , Th1 Cells/metabolism , Th17 Cells/drug effects , Th17 Cells/immunology , Th17 Cells/metabolism , Th2 Cells/drug effects , Th2 Cells/immunology , Th2 Cells/metabolism , Time Factors , Tumor Necrosis Factor-alpha/blood , Up-Regulation
3.
J Affect Disord ; 331: 442-451, 2023 06 15.
Article in English | MEDLINE | ID: mdl-36963515

ABSTRACT

BACKGROUND: Caring Contacts can effectively reduce suicide ideation, attempts, and death. In published clinical trials, Caring Contacts were sent by someone who knew the recipient. At scale, Caring Contacts programs rarely introduce the recipient and sender. It is not known whether receiving Caring Contacts from someone unknown is as effective as messages from someone the recipient has met. METHODS: Pragmatic randomized controlled trial comparing Caring Contacts with (CC+) versus without an introductory phone call (CC). Recruitment occurred January-July 2021, with outcomes assessed at 6 months. Participants were primary care patients or healthcare providers/staff reporting adverse mental health outcomes on a qualifying survey. Participants were sent 11 standardized caring text messages over 6 months; when participants replied, they received personalized unscripted responses. CC+ calls were semi-structured. The primary outcome was loneliness (NIH Toolkit). RESULTS: Participants included 331 patients (mean [SD] age: 45.5 [16.4], 78.9 % female) and 335 healthcare providers/staff (mean [SD] age: 40.9 [11.8], 86.6 % female). There were no significant differences in loneliness at 6 months by treatment arm in either stratum. In patients, mean (SD) loneliness was 61.9 (10.7) in CC, and 60.8 (10.3) in CC+, adjusted mean difference of -1.0 (95 % CI: -3.0, 1.0); p-value = 0.31. In providers/staff, mean (SD) loneliness was 61.2 (11) in CC, and 61.3 (11.1) in CC+, adjusted mean difference of 0.2 (95 % CI: -1.8, 2.2); p-value = 0.83. LIMITATIONS: Study population was 93 % white which may limit generalizability. CONCLUSIONS: Including an initial phone call added operational complexity without significantly improving the effectiveness of a Caring Contacts program.


Subject(s)
Mental Disorders , Text Messaging , Humans , Female , Middle Aged , Adult , Male , Loneliness , Suicidal Ideation , Health Personnel
4.
Contemp Clin Trials ; 131: 107268, 2023 08.
Article in English | MEDLINE | ID: mdl-37321352

ABSTRACT

BACKGROUND: Suicide is a leading cause of death in adolescents and adults in the US. Follow-up support delivered when patients return home after an emergency department (ED) or primary care encounter can significantly reduce suicidal ideation and attempts. Two follow-up models to augment usual care including the Safety Planning Intervention have high efficacy: Instrumental Support Calls (ISC) and Caring Contacts (CC) two-way text messages, but they have never been compared to assess which works best. This protocol for the Suicide Prevention Among Recipients of Care (SPARC) Trial aims to determine which model is most effective for adolescents and adults with suicide risk. METHODS: The SPARC Trial is a pragmatic randomized controlled trial comparing the effectiveness of ISC versus CC. The sample includes 720 adolescents (12-17 years) and 790 adults (18+ years) who screen positive for suicide risk during an ED or primary care encounter. All participants receive usual care and are randomized 1:1 to ISC or CC. The state suicide hotline delivers both follow-up interventions. The trial is single-masked, with participants unaware of the alternative treatment, and is stratified by adolescents/adults. The primary outcome is suicidal ideation and behavior, measured using the Columbia Suicide Severity Rating Scale (C-SSRS) screener at 6 months. Secondary outcomes include C-SSRS at 12 months, and loneliness, return to crisis care for suicidality, and utilization of outpatient mental health services at 6 and 12 months. DISCUSSION: Directly comparing ISC and CC will determine which follow-up intervention is most effective for suicide prevention in adolescents and adults.


Subject(s)
Suicide , Text Messaging , Adolescent , Adult , Humans , Emergency Service, Hospital , Primary Health Care , Suicidal Ideation , Suicide/psychology , Suicide Prevention , Pragmatic Clinical Trials as Topic
5.
Catalysts ; 12(10)2022 Oct.
Article in English | MEDLINE | ID: mdl-36405766

ABSTRACT

Zinc oxide is an environmentally friendly and readily synthesized semiconductor with many industrial applications. ZnO powders were prepared by alkali precipitation using different [Zn(acetate)2(amine)x] compounds to alter the particle size and aspect ratio. Slow precipitations from 95 °C solutions produced micron-scale particles with morphologies of hexagonal plates, rods, and needles, depending on the precursor used. Powders prepared at 65 °C with rapid precipitation yielded particles with minimal morphology differences, but particle size was dependent on the precursor used. The smallest particles were produced using precursors that yielded crystals with low aspect ratios during high-temperature synthesis. Particles produced during rapid synthesis had sizes ranging from 21-45 nm. The materials were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, BET, and diffuse reflectance. The materials prepared using precursors with less-volatile amines were found to retain more organic material than ZnO produced using precursors with more volatile amines. The amount of organic material associated with the nanoparticles influenced the photocatalytic activity of the ZnO, with powders containing less organic material producing faster rate constants for the decolorizing of malachite green solutions under ultraviolet illumination, independent of particle size. [Zn(acetate)2(hydrazine)2] produced ZnO with the fastest rate constant and was recycled five times for dye degradation studies that revealed minimal to no reduction in catalytic efficiency.

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