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H Kara

Publications and source records attributed to H Kara.

At least 19 recordsLinked to original sources
PubMed2005

The sorption behavior of a nickel-insolubilized humic acid system in a column arrangement.

The sorption characteristics of insolubilized humic acid (IHA) were investigated for Ni (II) in a column arrangement. The sodium form of the IHA (INaA) was used as a solid phase. Column operations were performed with five steps and all of them were monitored continuously by a flowthrough cell-adapted UV-Vis spectrophotometer. Thus, all solid-phase extraction (SPE) steps were visualized by breakthrough curves and analyses progress were evaluated. However, all calculations and evaluations were focused on the atomic absorption spectrophotometric (AAS) analyses of the solutions collected during the stripping steps. There was a high correlation (r(2), 0.972) between peak area and AAS data of stripping steps. The effect of concentration and pH of the loading solution onto sorption of Ni (II) by INaA was investigated. Sorption characteristics were evaluated by using Freundlich, Langmuir, and Dubinin-Radushkevich (D-R) adsorption isotherms, as well as by Scatchard plot analysis. Multilayer sorption was found to be agreeable for Ni (II). From the D-R isotherm the mean free energy of sorption (E) was calculated (6.65 kJ mol(-1)) and attributed to the multilayer sorption. Finally, the sorption characteristic of the INaA-Ni (II) system was compared with that of the INaA-Cu (II) system, and possible separation of two ions in a binary mixture system is discussed.

Adsorption↗
PubMed2005

Finite element modelling of dense and porous piezoceramic disc hydrophones.

The acoustic characteristics of dense and porous piezoceramic disc hydrophones have been studied by finite element modelling (FEM). The FEM results are validated initially by an analytical model for a simple disc of dense piezoceramic material and then it is extended to a porous piezoceramic disc replicating a foam-reticulated sample. Axisymmetric model was used for dense piezoceramic hydrophone due its regular geometric shape. 3-dimensional model was used for the porous piezoceramics, since the unit cell model is inadequate to fully represent transducers of finite lateral dimensions. The porous PZT discs have been synthesised by foam-reticulation technique. The electrical impedance and the receiving sensitivity of the hydrophones in water are evaluated in the frequency range 10-100 kHz. The model results are compared with the experimental data. The receiving sensitivity of piezocomposite hydrophones is found to be reasonably constant over the frequency range studied. The sharp resonance peaks observed for the dense piezoceramic hydrophone has broadened to a large extent for porous piezoceramic hydrophones, indicating higher losses. The flat frequency response suggests that the 3-3 piezocomposites are useful for wide-band hydrophone applications.

Journal Article↗
PubMed2005

Penetrating type intraosseous ganglion cyst of the lunate bone.

Intraosseous ganglion cysts of the carpal bones located in the lunate are one of the rarely seen pathologic conditions. Here we present a case of the penetrating type of intraosseous ganglion cyst located in the lunate as an uncommon cause of wrist pain. The patient was successfully treated by surgical intervention. Intraosseous ganglion cyst should be considered in the differential diagnosis of chronic dull wrist pain.

Adult↗
PubMed2004

Investigation of the properties of oil at the bleaching unit of an oil refinery.

Color removal from neutralized sunflower oil was studied with different kinds of commercial bleaching earths. The effect of changes in time (25 and 35 min), temperature (80-125 degrees C), and bleaching earth dosage (0.1-0.9% by weight) on color, chlorophyll and carotene concentrations, and oxidation degree were investigated. To obtain adsorption curves from coloring compounds adsorbed onto activated bleaching earths, the Langmuir and Freundlich equations was used, the constant parameters and correlation coefficient R were calculated for each type of bleaching earth, and color changes were explained by both adsorption isotherms. It was observed that an increase in bleaching earth dosage decreases color. Its effect on oxidation state, however, is complex and related to both primary and secondary oxidation products. In addition, an increase in temperature seems to decrease chlorophyll and carotene adsorptions. Generally, time beyond equilibrium is considered useless for the removal of unwanted components. This study also confirms this claim and reveals that the peroxide value does not indicate the oxidation state of the oil completely.

Journal Article↗
PubMed2002

Magnesium infusion reduces perioperative pain.

BACKGROUND AND OBJECTIVE: Magnesium has antinociceptive effects in animal and human models of pain. These effects are primarily based on the regulation of calcium influx into the cell. The aim of this study was to determine whether perioperative infusion of magnesium would reduce postoperative pain and anxiety. METHODS: Twenty-four patients, undergoing elective hysterectomy, received a bolus of 30 mg kg(-1) magnesium sulphate or the same volume of isotonic sodium chloride solution intravenously before the start of surgery and 0.5 g h(-1) infusion for the next 20 h. Intraoperative and postoperative analgesia were achieved with fentanyl and morphine respectively. Patients were evaluated pre- and postoperatively for anxiety. RESULTS: Fentanyl consumption and total morphine requirements were significantly decreased in the magnesium group compared to the control group. Postoperative anxiety scores and sedation were similar between groups. CONCLUSIONS: Continuous magnesium infusion, including the pre-, intra-, and postoperative periods reduces analgesic requirements. These results demonstrate that magnesium can be an adjuvant for perioperative analgesic management.

Adult↗
PubMed2002

Monitoring of organochlorine pesticide residues in pikeperch, Stizostedion lucioperca L. in Beysehir Lake (Central Anatolia).

Fishes in Beysehir Lake were analysed to determine organochlorine pesticide residues. The more frequently detected compounds are DDT complex (DDT, DDD, DDE and isomers), total HCH complex (alpha-HCH, beta-HCH and gamma-HCH or lindane), aldrin, dieldrin, endrin and heptachlorine. Eighty five percent of the fish samples were found to be contaminated. While 75% of the total samples were contaminated by one or more HCH isomers, 63% of the organochlorinated pesticide is DDT and its metabolites. Aldrin, dieldrin and endrin are minor pesticides in samples. Heptachlorine was found in only one sample. Despite their presence high concentrations are sporadic, the mean values being less than FAO/WHO maximum recommended limits.

Animals↗
PubMed2001

2-[1-(Hydroxyimino)ethyl]-2,5,5-trimethylperhydropyrimidine-butane-2,3-dione monooxime (1/1).

The title compound, C(9)H(19)N(3)O.C(4)H(7)NO(2), displays strong intramolecular O-H...N [O...N 2.6743 (13) A] and N-H...N [N...N 2.6791 (15) A] hydrogen bonds, and strong intermolecular O-H...N [O...N 2.7949 (15) A] and N-H...O [N...O 3.0924 (16) A] hydrogen bonds. This creates chains of perhydropyrimidine molecules, linked by hydrogen bonds. Each chain is linked to a partner chain, through hydrogen bonds to two butane-2,3-dione monooxime molecules, in a structure reminiscent of a ladder.

Journal Article↗
PubMed2000

Cobalt(II) and Nickel(II) Transfer through Charged Polysulfonated Cation Exchange Membranes.

The transport of Co(II) and Ni(II) ions through charged polysulfonated ion exchange membranes under Donnan dialysis conditions has been studied as a function of pH gradient at 25 degrees C. In the Donnan dialysis process, the membrane is bounded by two electrolyte solutions, the one side (donor phase) initially containing metal salts and the other H(2)SO(4) with no external potential field applied. The transport of metal ions through membranes was correlated with the flux data as well as with estimated diffusion coefficients and was found to depend on the interaction between the fixed groups in the membrane and the metal ions. It was observed that the pH gradient influences the transport of metals and the flux of ions increases with H ion concentration in the receiver phase. Copyright 2000 Academic Press.

Journal Article↗
PubMed2000

Do discrepancies between microsatellite and allozyme variation reveal differential selection between sea and lagoon in the sea bass (Dicentrarchus labrax)?

In the present study the genetic structure of Dicentrarchus labrax (14 samples from the Mediterranean) was analysed at six microsatellite loci, in order to test the hypothesis that some enzymatic loci undergo selection between marine and lagoon habitat. Eight of the 14 samples were analysed at both microsatellite and allozyme markers. The analysis of the genetic variation among the Mediterranean samples showed that (i) &Fcirc;ST values obtained with the six microsatellite loci were much smaller than those obtained with the 28 allozymes and (ii) microsatellite loci seemed to reflect more the geographical proximity than an ecological one. Thirteen enzymatic loci exhibited moderate to high values compared with microsatellites. This was interpreted as evidence that these allozymes are non-neutral. However, only six loci seemed to be implicated in differentiation between marine and lagoon samples, the causes of selection being unknown for the others. A possible scenario of population dynamics of the sea bass between marine and lagoon habitat is suggested.

Adaptation, Physiological↗
PubMed2000

(Benzoylacetonato)chloro(1,10-phenanthroline)copper(II)

The crystal structure of the title compound, chloro(1, 10-phenanthroline-N,N')(1-phenyl-1,3-butanedionato-O,O')copper(II), [CuCl(C(10)H(9)O(2))(C(12)H(8)N(2))], has been determined. The Cu(II) ion displays a distorted square-pyramidal coordination, being linked to the two O atoms of the benzoylacetonate ligand and the two N atoms of the 1,10-phenanthroline ligand in the basal plane, and the Cl atom in the apical site. TheCu-N, Cu-O and Cu-Cl bond lengths are 2.043 (2)/2.025 (2), 1.914 (2)/1.941 (2) and 2.485 (1) A, respectively.

Journal Article↗
PubMed1998

Hypnotizability, pain threshold, and dissociative experiences.

BACKGROUND: There may be an association between pain threshold, hypnotizability, and dissociative experiences. The purpose of the present study was to examine this association. METHODS: Forty-one healthy subjects were included in the study. Pain thresholds were determined using a manual algometer. The Dissociative Experiences Scale was administered to all subjects. Hypnotizability of the subjects was assessed by the eye roll sign of the Hypnotic Induction Profile. There were 14, 15, and 12 subjects in the Grade 1, 2, and 3 groups, respectively. RESULTS: Highly hypnotizable subjects had lower pain thresholds and were more likely to report dissociative experiences than the less hypnotizable subjects. CONCLUSIONS: There is an association between pain threshold, hypnotizability, and dissociative experiences. It may be suggested that dissociative and somatic symptoms may be integrally linked and related to hypnotic suggestibility.

Adult↗
PubMed1998

Low cholesterol level in patients with panic disorder: the association with major depression.

BACKGROUND: The purpose of this study was to examine whether an association exists between low cholesterol level and major depression in patients with panic disorder. METHODS: The subjects of the study were 16 patients panic disorder only, 16 panic disorder patients had also current major depressive episode, and 16 normal control subjects. An automated enzymatic colorimetric method was used for cholesterol determination. RESULTS: Panic disorder patients had higher serum cholesterol than panic disorder patients with major depression and normal controls. CONCLUSION: There is an association between low cholesterol level and the presence of major depression in patients with panic disorder. LIMITATION: Future studies with large sample are needed to confirm this finding. CLINICAL RELEVANCE: A low serum cholesterol level might serve as biological marker of major depression in patients panic disorder.

Adult↗
PubMed1997

Acupuncture and hypnotic suggestions in the treatment of non-organic male sexual dysfunction.

We have examined the effects of acupuncture and hypnotic suggestions, and compared them with placebo in the treatment of male sexual dysfunction with no detectable organic cause. The study comprised 15 men (mean age 36.7 +/- 10.43 years) who received acupuncture treatment, 16 men (mean age 38.4 +/- 10.75 years) who underwent hypnosis (mean age 35.3 +/- 11.52 years) and 29 men (mean age 36.2 +/- 11.38 years) who served as controls. They were interviewed periodically; the patients' reports were verified by interviewing their partners. Men who received placebo had a 43-47% improvement in sexual function, while the rates of improvement in the treated groups were higher, but not significantly so. The success rates of acupuncture and hypnotic suggestions were 60% and 75% respectively. Although the improvement was not statistically significant, treatment with acupuncture could be used as an adjuvant therapy in non-organic male sexual dysfunction. The only treatment superior to placebo seemed to be hypnosis. A more effective treatment may be obtained by combining these therapeutic modalities, but this needs further study.

Acupuncture Therapy↗
PubMed1997

Sleep disturbances and suicidal behavior in patients with major depression.

BACKGROUND: The purpose of this study was to examine the association between sleep disturbances and suicidal behavior in patients with major depression (N = 113). METHOD: The sleep symptomatology of each patient was ascertained from the Schedule for Affective Disorders and Schizophrenia (SADS) questions concerning sleep in the section on major depression. The patients were retrospectively classified as having hypersomnia (N = 20), insomnia (N = 69), and no sleep disturbance (N = 24). The SADS suicide subscale was used to rate the severity of active suicidality. RESULTS: The patients with hypersomnia and insomnia had significantly (p < .05) higher scores on the SADS suicide subscale than those without sleep disturbance. We also found that the patients with insomnia and hypersomnia were significantly (p < .001) more likely to become suicidal than the others. CONCLUSION: These data demonstrate that both insomnia and hypersomnia are associated with suicidal behavior in patients with major depression.

Adult↗
PubMed1996

Efficacy of testosterone, trazodone and hypnotic suggestion in the treatment of non-organic male sexual dysfunction.

OBJECTIVE: To examine the effects of hypnotic suggestions or the administration of testosterone or trazodone to impotent men with no detectable organic cause for the impotence. PATIENTS AND METHODS: The study comprised 79 men in whom clinical and laboratory examinations revealed no organic cause for their impotence: 20 men (mean age 38.7 +/- 11.47 years) received testosterone, 21 men (mean age 39.5 +/- 10.73 years) received trazodone, 20 men (mean age 34.2 +/- 11.69 years) underwent hypnosis and 18 men (mean age 39.1 +/- 11.46 years) served as controls. They were assessed by interview 4, 6 and 8 weeks after starting treatment: the patient's reports were verified by interviewing their partners. RESULTS: Men who received a placebo had a 39% improvement in sexual function, while the rates of improvement in the treated groups were higher, but not significantly so. The success rates of testosterone and trazodone treatment and hypnotic suggestions were 60%, 67% and 80%, respectively. CONCLUSION: Although the improvement was not statistically significant, treatment with testosterone and trazodone could be used as an adjuvant therapy in nonorganic male sexual dysfunction. The only treatment superior to placebo seemed to be hypnosis. A more effective treatment may be obtained by combining these therapeutic modalities, but this needs further study.

Adult↗
PubMed1996

The efficacy of fluoxetine in the treatment of premature ejaculation: a double-blind placebo controlled study.

PURPOSE: The efficacy of the selective serotonin re-uptake inhibitor fluoxetine in the treatment of premature ejaculation was examined. MATERIALS AND METHODS: The study comprised 17 patients with premature ejaculation who presented to the urology clinic of our medical school. In this double-blind study the patients were randomized into treatment groups receiving 20 mg. fluoxetine daily for 1 week and 40 mg. daily afterward (group 1) or 1 capsule placebo daily for 1 week and 2 capsules daily afterward (group 2). The groups were evaluated according to the latent period of intravaginal ejaculation. RESULTS: The latent period of intravaginal ejaculation in group 1 was significantly longer than that in group 2. Nausea, headache and insomnia were reported side effects. CONCLUSIONS: Fluoxetine may be regarded as a safe and effective alternative in the treatment of premature ejaculation.

Adolescent↗