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1.
Chemosphere ; 353: 141504, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403120

RESUMO

The selective removal of pollutants from water bodies is regarded as a conciliation between the rapid expansion of industrial activities and need of clean water for sustainability. Fluoride is one such geogenic pollutant, and various materials have already been reported. Developing an efficient field employable material is however a challenge. Herein, we report the synthesis and competencies of strategically designed magnetic La-doped Al2O3 core-shell nanoparticle loaded polymeric nanohybrid as a benchmark fluoride sorbent. A facile synthesis strategy involved fabrication of Fe3O4 magnetic core followed by growth of La doped Al2O3 shell using sol-gel method. Doping of La2O3 into Al2O3 structure was optimised (6%), resulting in Fe3O4-Al0.94 La0.06O1.5 core-shell particles which provided exceptional fluoride affinity. The obtained magnetic Fe3O4-Al0.94La0.06O1.5 core-shell nanoparticles were then loaded (22%) into alginate to form cross-linked hydrogel beads (Fe3O4-Al0.94 La0.06 O1.5-Ca-ALG). These prepared hydrogel beads were characterised and utilized for selective recovery of fluoride under different ambient conditions. Driving forces for enhanced fluoride uptake by La doped Al2O3 were investigated and explained with the help of both experimental observation and theoretical simulation. Density functional theory calculations indicated significant expansion in the cell volume of Al2O3 due to La doping which favoured the fluoride sorption. The calculated defect formation energy for the incorporation of F into Al2O3 was found to decrease in the presence of La. XPS analysis suggested direct interaction of fluoride with Al, forming Al-F bond and breaking Al-O bond. Different vital parameters for uptake were optimised. Also, kinetics, isotherm and diffusion models were evaluated. Developed hydrogel beads attained record sorption capacity of 132.3 mgg-1 for fluoride. Overall, excellent stability, no leaching of constituents, effectiveness for selective fluoride recovery from groundwater, brand it a perfect epitome of sustainable water treatment application.


Assuntos
Fluoretos , Nanopartículas , Hidrogéis/química , Adsorção , Fenômenos Magnéticos , Cinética
2.
ACS Appl Mater Interfaces ; 6(21): 18619-25, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25318103

RESUMO

In the present work, we report on the investigation of low-temperature (300-5 K) thermoelectric properties of hot-pressed TiSe2, a charge-density-wave (CDW) material. We demonstrate that, with increasing hot-pressing temperature, the density of TiSe2 increases and becomes nonstoichiometric owing to the loss of selenium. X-ray diffraction, scanning electron microscopy, and transimission electron microscopy results show that the material consists of a layered microstructure with several defects. Increasing the hot-press temperature in nonstoichiometric TiSe2 leads to a reduction of the resistivity and enhancement of the Seebeck coefficient in concomitent with suppression of CDW. Samples hot-pressed at 850 °C exhibited a minimum thermal conductivity (κ) of 1.5 W/m·K at 300 K that, in turn, resulted in a figure-of-merit (ZT) value of 0.14. This value is higher by 6 orders of magnitude compared to 1.49 × 10(-7) obtained for cold-pressed samples annealed at 850 °C. The enhancement of ZT in hot-pressed samples is attributed to (i) a reduced thermal conductivity owing to enhanced phonon scattering and (ii) improved power factor (α(2)σ).

3.
J Phys Condens Matter ; 26(44): 445002, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25244149

RESUMO

In this paper we report the thermoelectric performance of Sr intercalated TiSe(2) above 300 K. Refined x-ray diffraction, high resolution transmission electron microscopy and scanning electron microscopy images show well oriented polycrystalline grains along a (0 0 l) direction and layered growth of the sample. Intercalation of Sr in TiSe(2) shows an improved Seebeck coefficient (α) value without altering the polarity of the majority charge carrier. A drastic reduction in the thermal conductivity (κ) from 3.8 W m K(-1) to 1.2 W m K(-1) (at 650 K) was observed which is ascribed to the: (i) scattering of the phonon by natural layer interfaces, grain boundaries and lattice defects and (ii) rattling of intercalated Sr atoms among weakly bound TiSe(2) layers. This led to the maximum ZT of ~0.08 at 650 K for Sr(x)TiSe(2) (x > 0.1) which is almost twice as high as the parent TiSe(2).

4.
Clin Schizophr Relat Psychoses ; 5(2): 75-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21693430

RESUMO

For patients who gain a troublesome amount of weight on antipsychotics, switching to a less obesogenic agent is an option. Aripiprazole appears to cause less weight gain than many other antipsychotics. We report on changes in weight, and other risk factors for heart disease, in thirty-three schizophrenia patients who agreed to switch from other antipsychotics to aripiprazole in an open, flexible-dose, eight-week trial. All patients were successfully switched. There were no significant changes in PANSS symptom scores or in CGI. Weight (Wt), waist circumference (WC), and low-density lipoprotein (LDL) decreased significantly in the group as a whole. In patients switched from olanzapine to aripiprazole, Wt, WC, LDL, fasting glucose, and triglycerides were significantly decreased as compared to baseline. Substantial decreases in several risk factors were also seen in patients switched from quetiapine, but these changes did not reach statistical significance.


Assuntos
Antipsicóticos/farmacologia , Substituição de Medicamentos , Sobrepeso/prevenção & controle , Piperazinas/farmacologia , Quinolonas/farmacologia , Esquizofrenia/tratamento farmacológico , Redução de Peso/efeitos dos fármacos , Aripiprazol , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Masculino , Síndrome Metabólica/prevenção & controle , Pessoa de Meia-Idade
5.
Asian J Psychiatr ; 2(3): 106-11, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23051050

RESUMO

This study evaluated changes in the metabolic syndrome (MetS) parameters among patients with schizoaffective disorder-bipolar type who had previously participated in a randomized, placebo-controlled study of topiramate (Chengappa et al., 2007). Topiramate (or placebo) was added to pre-existing mood-stabilizer and/or antipsychotic treatment. Nearly 41% of the 46 participants with fully available data met criteria for MetS at the pre-study baseline, and six (13%) additional subjects met criteria for MetS during the 16-week study. Several subjects (mostly topiramate treated) showed the hypothesized and expected loss in body weight and this correlated with improved glycosylated hemoglobin or systolic and diastolic blood pressure measurements or improvements in lipid levels, whereas a few patients had inconsistent results. Limitations of the study include the lack of targeted treatments for specific components of the metabolic syndrome, and no controls for exercise, diet or concomitant medications. Nevertheless, screening, monitoring and targeted treatment for the metabolic syndrome in psychiatric patients is increasingly becoming the standard of practice. Moreover and especially pertinent to the readership of this journal is that as the prevalence of overweight and MetS have increased worldwide, the World Health Organization has proposed lower cut-off thresholds for obesity in Asia. Furthermore, lower thresholds for waist circumference have also been recommended for Asians.

6.
Bipolar Disord ; 9(6): 609-17, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17845276

RESUMO

OBJECTIVES: This pilot study evaluated the efficacy and safety of adjunctive topiramate compared with placebo in the treatment of patients with a diagnosis of schizoaffective disorder, bipolar type (SAD-BT). METHODS: A sample of 48 adult patients with a Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) diagnosis of SAD-BT (supported by the Structured Clinical Interview for DSM-IV Axis I Disorder, Patient Edition) were randomly assigned in a 2:1 ratio (favoring topiramate) to 8 weeks of double-blind treatment with topiramate (100-400 mg/day) or placebo. Patients who had achieved a > or =20% decrease from baseline in their Positive and Negative Syndrome Scale (PANSS) total scores were given the opportunity to continue for an additional 8 weeks of double-blind treatment. The dosage of the study medicine was continued unchanged from the earlier 8-week study period. At the end of the study period, the study medicine was tapered and discontinued over a 2-week period. Primary efficacy was assessed at 8 weeks using the mean change between treatment groups of the PANSS total scores in the intent-to-treat population of randomized patients. Several secondary measures were also assessed. Safety analyses included monitoring of adverse events, vital signs, electrocardiogram (ECG) and laboratory values. RESULTS: Even though both treatments reduced scores on various psychopathology rating scales, adjunctive topiramate treatment (nearly 275 mg/day) did not show increased efficacy relative to placebo on the primary outcome measure (PANSS scale) or any of the secondary outcome measures. Topiramate-treated patients lost significantly more body weight than placebo-treated patients, which led to a significant reduction in body mass index (BMI). Relative to adjunctive placebo, topiramate-treated patients experienced higher rates of paresthesia, sedation, word-finding difficulty, sleepiness, and forgetfulness, but these differences were not statistically significant. There were no clinically significant abnormalities in either the ECG or laboratory results. There were no serious adverse events in the study. Further, there was no worsening of the PANSS total scores (to > or =10% from baseline), and no significant differences between the treatments on worsening of total Montgomery-Asberg Depression Rating Scale (MADRS) scores [1/13 (7.7%) for placebo; 1/25 (4.0%) for topiramate]. CONCLUSIONS: This pilot study did not support clinical efficacy for adjunctive topiramate treatment in patients with SAD-BT. There were no major safety or tolerability issues in this study. Confirming the results of other studies, topiramate-treated patients did experience greater body weight loss and reduction in BMI.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Frutose/análogos & derivados , Transtornos Psicóticos/tratamento farmacológico , Adulto , Transtorno Bipolar/fisiopatologia , Índice de Massa Corporal , Manual Diagnóstico e Estatístico de Transtornos Mentais , Método Duplo-Cego , Eletrocardiografia , Feminino , Frutose/administração & dosagem , Frutose/efeitos adversos , Humanos , Masculino , Projetos Piloto , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/fisiopatologia , Topiramato , Resultado do Tratamento
7.
Neuropsychiatr Dis Treat ; 2(2): 241-3, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19412470

RESUMO

A series of cases are reported in which patients on aripiprazole have developed akathisia, although the literature states that the rate is negligible.

8.
Bipolar Disord ; 6(4): 314-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15225149

RESUMO

OBJECTIVES: To evaluate the point prevalence of the metabolic syndrome in patients with schizoaffective disorder--bipolar type. METHODS: Consenting patients who were participants in an ongoing clinical trial of adjunctive topiramate treatment for schizoaffective disorder, bipolar type were evaluated at baseline for the point prevalence of the metabolic syndrome. The criteria for the metabolic syndrome included: (a) waist circumference > 102 cm (40 inches) in males, or > 88 cm (35 inches) in females; (b) fasting serum triglyceride levels > or = 150 mg/dL; (c) fasting high density lipoproteins (HDL) cholesterol <40 mg/dL in men or <50 mg/dL in women; (d) blood pressure > or = 130/85 mmHg; and (e) fasting glucose > or = 110 mg/dL. Subjects who had at least three of these five criteria were defined as meeting criteria for the metabolic syndrome. RESULTS: Thirty-six subjects (males = 15, females = 21) were evaluated, and three were excluded for missing data. Among those 33 subjects with complete data, 14 subjects (42.4%, males = 7, females = 7, African Americans = 6, Caucasians = 8) met criteria for the metabolic syndrome. Not unexpectedly, those with the metabolic syndrome were significantly more likely to be obese, and have significantly higher mean systolic and diastolic blood pressure, mean fasting triglyceride levels and larger mean waist circumferences, and significantly lower HDL cholesterol levels; and a trend toward higher fasting blood glucose levels. Furthermore, the fasting mean total cholesterol in those with the metabolic syndrome was 217 mg/dL (+/-46). CONCLUSIONS: This preliminary report suggests that the point prevalence of the metabolic syndrome in patients with schizoaffective disorder appears to be higher than that reported in the general population of the USA. Targeted weight reduction and life style change strategies (increased exercise, smoking cessation, stress reduction) may provide useful interventions to decrease the morbidity and mortality that accompanies the presence of the metabolic syndrome in patients with psychiatric illnesses.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/epidemiologia , Frutose/análogos & derivados , Frutose/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/epidemiologia , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/epidemiologia , Adulto , Índice de Massa Corporal , HDL-Colesterol/sangue , Comorbidade , Demografia , Método Duplo-Cego , Feminino , Humanos , Hipercolesterolemia/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Tempo , Topiramato , Triglicerídeos/sangue
9.
Am J Geriatr Psychiatry ; 11(2): 205-13, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12611750

RESUMO

OBJECTIVE: The authors sought to identify patterns and associations of prescription and over-the-counter sedative-hypnotic use in an older, rural, blue-collar, community-based cohort in southwestern Pennsylvania over 10 years. METHODS: A group of 1,627 individuals age 65 and over were recruited and assessed during 1987-1989 and re-assessed during approximately biennial waves. Data included sleep medications, demographics, depressive symptoms, sleep complaints, and cognitive functioning (Mini-Mental State Exam [MMSE]). RESULTS: At Waves 1 through 5, the mean age of the cohort increased from 73.4 to 80.5 years. Use of prescription sedative-hypnotics (primarily benzodiazepines) increased from 1.8% to 3.1%, and over-the-counter sedative-hypnotic use (primarily diphenhydramine) increased from 0.4% to 7.6%. At Wave 5 (1996-1998), 8.17% of the sample reported using diphenhydramine as a sleep aid. After adjusting for age and sex, diphenhydramine use was associated with higher education and more depressive symptoms, the latter becoming nonsignificant after controlling for initial insomnia. MMSE became significantly associated with diphenhydramine use when 143 subjects with dementia were excluded from the analysis. CONCLUSION: As the cohort aged, prescription sedative-hypnotic use remained relatively stable, whereas over-the-counter sedative use, principally diphenhydramine, increased substantially. The association of this drug with cognitive impairment in persons without dementia highlights its potential for causing adverse reactions in older adults.


Assuntos
Transtornos Cognitivos/epidemiologia , Difenidramina/uso terapêutico , Uso de Medicamentos/estatística & dados numéricos , Hipnóticos e Sedativos/uso terapêutico , Sistema de Registros , Serviços de Saúde Rural , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/epidemiologia , Área Programática de Saúde , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/diagnóstico , Estudos de Coortes , Coleta de Dados , Depressão/tratamento farmacológico , Depressão/etiologia , Difenidramina/administração & dosagem , Difenidramina/efeitos adversos , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Masculino , Programas de Rastreamento , Testes Neuropsicológicos , Pennsylvania/epidemiologia , Vigilância da População , Distúrbios do Início e da Manutenção do Sono/epidemiologia
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