Intercalated Water Drives Anomalous Thermal Expansion in the Tetragonal Zircon Structured Bismuth Vanadate BiVO4 Photocatalyst.

The thermal transformation of the tetragonal-zircon (tz-) to tetragonal-scheelite (ts-)BiVO4 was studied by in situ synchrotron X-ray diffraction, thermogravimetric analysis, and Fourier-transformed infrared spectroscopy. Upon heating, the tetragonal zircon polymorph of BiVO4 (tz-BiVO4) transitioned to the ts-polymorph between 693-773 K. Above 773 K, single phase ts-BiVO4 was observed before transitioning to the monoclinic fergusonite (mf-) polymorph upon cooling. An anomaly in thermal expansion was observed between 400-500 K, associated with the loss of intercalated H2O/NH4 + from the coprecipitation procedure. Heating tz-BiVO4 resulted in contraction of the V-O bond distance and VO4 polyhedra volume, ascribed to rotation of the tetrahedra groups. Attempts to study this by neutron diffraction failed due to the large incoherent scatter from the hydrogenous species. Efforts to remove these species while maintaining the tz-BiVO4 structure were unsuccessful, suggesting they play a role in stabilizing the tz-polymorph. The local structure of both mf-BiVO4 and tz-BiVO4 were investigated by X-ray pair distribution function analysis, revealing local distortions.

Estimating the parameters of a dependent model and applying it to environmental data set.

In this paper, a new dependent model is introduced. The model is motivated using the structure of series-parallel systems consisting of two series-parallel systems with a random number of parallel sub-systems that have fixed components connected in series. The dependence properties of the proposed model are studied. Two estimation methods, namely the moment method, and the maximum likelihood method are applied to estimate the parameters of the distributions of the components based on observing the system's lifetime data. A Monte Carlo simulation study is used to evaluate the performance of the estimators. Two real data sets are used to illustrate the proposed method. The results are useful for researchers and practitioners interested in analyzing bivariate data related to extreme events.

Risk of gestational diabetes mellitus in patients undergoing assisted reproductive techniques.

OBJECTIVE: To compare the incidence of gestational diabetes mellitus (GDM) between pregnancies conceived spontaneously and pregnancies conceived following assisted reproductive technology (ART). STUDY DESIGN: This cross-sectional study evaluated the medical records of 215 women who conceived spontaneously and 145 women who conceived following ART from September 2011 to October 2012. Exclusion criteria were: polycystic ovary syndrome, maternal age ≥40 years, family history of diabetes in first-degree relatives, pre-pregnancy diabetes, glucose intolerance treated with hypoglycaemic agent (e.g. metformin), history of GDM, history of stillbirth, recurrent miscarriage, history of baby with birth weight ≥4kg (macrosomia), parity >3, Cushing syndrome, congenital adrenal hyperplasia and hypothyroidism. For better comparison of the incidence of GDM, the ART group was further subdivided into: (i) an in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) group (n=95); and (ii) an intrauterine insemination (IUI) group (n=50). The diagnosis of GDM was based on the criteria of the American Diabetes Association. RESULTS: The incidence of GDM was significantly higher in the IVF/ICSI and IUI groups (43% and 26%, respectively) compared with the spontaneous pregnancy group (10%). Age, pre-pregnancy body mass index (BMI) and weight gain in pregnancy were similar among women with GDM in all three groups. In addition, the incidence of pregnancy-induced hypertension was significantly higher in the IVF/ICSI group (21%) compared with the spontaneous pregnancy group (7%). Logistic regression analysis demonstrated four strong risk factors for GDM: age, BMI, mode of ART and progesterone use during pregnancy. CONCLUSION: This study indicated that the risk of GDM is two-fold higher in women with singleton pregnancies conceived following ART compared with women who conceived spontaneously. In addition, progesterone use during pregnancy was found to be an important risk factor for GDM. This subject requires further study.

Hyperhomocysteinemia after kidney transplantation.

OBJECTIVE: To determine the prevalence of hyperhomocysteinemia (plasma homocysteine[Hcy] concentration≥15 µmol/L) and evaluate its correlation with allograft function. MATERIALS AND METHODS: The study included 159 stable renal transplant recipients (104 men and 55 women). The prevalence and severity of hyperhomocysteinemia were compared in the transplant recipients vs 72 patients (48 men and 24 women) receiving hemodialysis therapy. RESULTS: The mean (SD; range) fasting total Hcy concentration was higher in the hemodialysis group compared with the renal transplantation group: 27.4 (18.3; 10-95) µmol/L vs 16.6 (9.5; 4.5-45.0) µmol/L (P=.00). Hyperhomocysteinemia occurred more frequently in patients receiving hemodialysis therapy (74% vs 49%). No significant correlation was observed between Hcy concentration and recipient sex, cyclosporine trough concentration and concentration at 2 days after dosing, dyslipidemia,cytomegalovirus infection, diabetes mellitus, or aspartate or alanine aminotransferase concentration. Multivariate regression analysis revealed that serum creatinine concentration (P=.02) was the major determinant of increased total Hcy concentration in renal transplant recipients. CONCLUSION: A high prevalence of moderate hyperhomocysteinemia was observed in renal transplant recipients. There was no correlation between graft function and Hcy concentration.

Inguinal hernia and occurrence on the other side: a prospective analysis in Iran.

BACKGROUND: Indirect inguinal hernia (IH) is the most common type of hernia. Routine contralateral inguinal exploration, without clinical evidence of a hernia is still controversial especially in children. The purpose of our study was to determine incidence of contralateral IH. METHODS: This is a prospective study of 301 patients during a one-year period. History of groin mass, positive findings, demonstrable hernia, or communicating hydrocele were our criteria for diagnosis. RESULTS: Our study includes 301 infants and children, 270 (89.7%) males and 31 (10.3%) females with mean age of two years and 40.9% under six months. In the follow-up period, we found 33 new IH in our patients. 23 (12%) of 196 patients less than two years old underwent contralateral herniorrhaphy in the follow-up period (P = 0.02). Six patients of 30 premature children underwent contralateral herniorrhaphy (P = 0.03). CONCLUSION: The incidence of contralateral hernia is approximately 10% and in our study it is approximately 1.7%. There is a significant difference between the occurrence of contralateral hernia in preterm compared with term infants (P = 0.03). We think that the incidence is still too low to recommend routine contralateral exploration.

Frequency of and barriers to utilization of mental health services in an Iranian population.

This study in 2005 compared the need for mental health services, actual use of services and barriers to use by 3 groups in Shiraz city in the Islamic Republic of Iran: a sample of the general population, parents of children with mental illness and primary-school teachers. Among the general population, 76.0% reported that they had wanted help in the previous 6 months and, of these, 50.0% actually sought it. The rates for parents of children with mental problems were 81.3% and 55.4% and for teachers were 60.0% and 35.0% respectively. The most common barriers to service use were logistic, especially the cost of and inconvenient access to services. Barriers related to perceptions of mental health services were also important, such as lack of trust and perceptions of friends/family.

Frequency of and barriers to utilization of mental health services in an Iranian population

This study in 2005 compared the need for mental health services, actual use of services and barriers to use by 3 groups in Shiraz city in the Islamic Republic of Iran: a sample of the general population, parents of children with mental illness and primary-school teachers. Among the general population, 76.0% reported that they had wanted help in the previous 6 months and, of these, 50.0% actually sought it. The rates for parents of children with mental problems were 81.3% and 55.4% and for teachers were 60.0% and 35.0% respectively. The most common barriers to service use were logistic, especially the cost of and inconvenient access to services. Barriers related to perceptions of mental health services were also important, such as lack of trust and perceptions of friends/family

Prevalence of subjective poor health symptoms associated with exposure to electromagnetic fields among university students.

The number of people complaining about different symptoms that may be associated with exposure to electromagnetic fields (EMF) has increased rapidly during past years. Students use both mobile phones and video display terminals frequently. The purpose of this study was to investigate the association of mobile phone use and EMF health hazards. Basic demographic data and self-reported symptoms were sought using a questionnaire administered to all apparently healthy students at Rafsanjan University of Medical Sciences (RUMS) and Vali-e-Asr University (VAU). Questions about some major confounding factors such as age, gender, amount of video display terminal work were also included. Exact Fischer Test was used for data analysis. Among self-reported symptoms, headache (53.5%), fatigue (35.6%), difficulties in concentration (32.5%), vertigo/dizziness (30.4%), attention disorders (28.8%), nervousness (28.1%), palpitation (14.7%), low back pain (14.3%), myalgia (12.4%), and tinnitus (9.9%) were the main self-reported symptoms. No significant differences in the prevalence of these symptoms were found between CRT users and those who did not use CRTs. A significant association was found between cordless phone use and difficulties in concentration (P < .05) or attention disorders (P < .05). However, after correction of the gender role, these differences were not significant. No association was found between mobile phone use and the above-mentioned symptoms. No significantly higher prevalence of self-reported symptoms was found in individuals who had used mobile phones, video display terminals or cordless phones more frequently than others. Mass-media's lack of interest in the possible hazards of exposure to EMF in developing countries can explain the difference observed between the results of this study and those of other researchers in some developed countries who have shown an association between EMF exposure and the prevalence of self-reported subjective symptoms. This finding can confirm the results obtained in provocative studies which indicated the role of psychological factors in electromagnetic hypersensitivity. More research is needed to clarify whether daily environmental EMF may cause health problems.

Current substance use in patients with gastric cancer in Southern Iran.

BACKGROUND: Psychiatric disorders may affect patients suffering from cancer and substance use disorders. OBJECTIVE: This study was undertaken to evaluate the prevalence of tobacco and opioid use in patients with gastric cancer in Shiraz, Fars Province and Southern Iran. MATERIALS AND METHODS: In a hospital survey of 177 gastric cancer patients aged 24 years and more, a semistructured-interview was performed based on SDM-IV criteria during the year 2003. RESULTS: The mean age of the patients was 58.13 (SD = 14.03) years. Among the subjects, 50.9% (90) were tobacco dependent (61.5% men and 29.4% women, P < 0.001), while 10 (5.7%) were opioid-dependent (7.3% men and 1.9% women, P = 0.16). Tobacco and opioid-dependency were not significantly related to age groups, economical or occupational status. Mean ages of tobacco and opioid-dependants were not significantly different from nondependants. CONCLUSIONS: Tobacco and opioid dependency were common problems among gastric cancer patients. This report provides useful information for health planning. Men were at greater risk than women. Treatment programs should focus on all age-groups, all occupations and all income-levels.

Naltrexone for alcohol-dependent patients.

BACKGROUND: Clinical trials have shown that naltrexone 50 mg/day reduces alcohol consumption and relapse rates in alcohol dependents. AIM: To investigate the efficacy of 50mg/day dose of naltrexone in the maintenance of alcohol-dependent subjects over a 36-week treatment period. METHODS: Subjects were randomised into two equal groups, consisting of 116 male alcohol-dependent patients who met the DSM-IV criteria for alcohol dependence and were seeking treatment. The participants received naltrexone or placebo at a dose of 50 mg/day and were treated in an outpatient clinic, offering a weekly 0.5-hour individual counselling session. Days retained in treatment were measured. RESULTS: Forty-one participants (35.3%) completed the 36-week study. Completion rates by group were 44.8% for the 50 mg naltrexone group and 25.9% for the placebo group (chi2=4.56, DF=1, 2-sided significance=0.033). CONCLUSION: The results support the efficacy and safety of naltrexone for outpatient treatment of alcohol-dependent individuals in Iran.

Controlled, randomized trial in maintenance treatment of intravenous buprenorphine dependence with naltrexone, methadone or buprenorphine: a novel study.

AIMS: To test the effect of a 50-mg day-1 dose of naltrexone in the maintenance treatment of intravenous-buprenorphine dependence in comparison with a 50-mg day-1 dose of methadone and also a 5-mg day-1 dose of buprenorphine over a 24-week treatment period. PARTICIPANTS: Two hundred and four intravenous-buprenorphine-dependent patients who met the DSM-IV criteria for opioid dependence were randomized to three equal groups and were treated in a clinic in Iran where they were also offered a weekly 0.5-h counselling session, in 2002. FINDINGS: The mean age was 31.2 years (range 17-53). The majority [63.2%] was between 20 and 34 years of age. The educational level of most of them [55.4%] was between 6 and 12 years of study. Completion rates by groups were 83.8% for the 50-mg dose methadone group, 58.8% for the 5-mg dose buprenorphine group and 20.6% for the 50-mg dose naltrexone group (P = 0.000). Retention in the 50-mg methadone group was significantly better than in the 5-mg dose buprenorphine group (P = 0.001) and the 50-mg dose naltrexone group (P = 0.000). Retention in the 5-mg buprenorphine group was significantly better than in the 50-mg naltrexone dose group (P = 0.000). CONCLUSIONS: Evaluation of the Iranian experience on this subject may be useful for other countries.

Controlled trial of maintenance treatment of intravenous buprenorphine dependence.

BACKGROUND: Buprenorphine dependence is a relatively novel addiction. AIMS: To compare the treatment outcome in three groups over 12-weeks of treatment. METHODS: Two hundred and four intravenous (i.v.)-buprenorphine-dependent patients were randomised into three groups. Subjects received 50 mg oral methadone tablet, or 5 mg sublingual buprenorphine tablet, or 50 mg oral naltrexone, and a weekly 30-minute clinical counselling session. RESULTS: The majority (80%) had a history of opium or heroin dependency before they were introduced to i.v. buprenorphine. The main source of buprenorphine for misusers was street sale (91%). The mean duration of buprenorphine dependence was 1.9 years and the mean dose per day was 3.9 ampoules (1 ampoule contains 0.3 mg of buprenorphine in 1 ml). Overall 59% of the patients completed the 12-week study. Retention in the 50 mg methadone group was significantly better than the 5 mg dose buprenorphine group (p=0.001) and the 50 mg dose naltrexone group (p=0.000). Retention in the 5 mg buprenorphine group was significantly better than the 50 mg naltrexone dose group (p=0.000). CONCLUSIONS: These results support the efficacy and safety of oral methadone and sublingual buprenorphine tablets for injection buprenorphine-dependent patients.

Cigarette smoking among Iranian medical students, resident physicians and attending physicians.

OBJECTIVE: This research assessed the prevalence of cigarette smoking among Iranian medical students, resident physicians and attending physicians. METHODS: Subjects (532 males and females) were selected randomly from Shiraz university of medical sciences and were administered by a questionnaire. FINDINGS: Of the participants 16.79% of males and 0.69% of females were smokers. Of the medical students, 18.48% of students, 12.5% of pre-externship students, 7.19% of externship students and 16.95% of internship students were smokers. Of resident physicians 11.11% were smokers. Among attending physicians 7.57% were smokers. The most common causes of current cigarette smoking were need (avoid withdrawal symptoms), pleasurable purposes and release of tension, respectively. Foreign filter tipped cigarette was the most common type of cigarette used. The mean of cigarette per day was 6.29 cigarettes and the mean age of starting cigarette was 19.71 years.

Prevalence of cigarette smoking in Iran.

The current research assessed the prevalence of cigarette smoking in Shiraz, Iran by randomly selecting 1,335 subjects (782 men and 553 women) from the city for a face-to-face interview and completion of a questionnaire. Of the participants, 205 (26%) of the men and 20 (3.6%) of the women reported being current smokers. The mean ages of smokers and nonsmokers were 41.8 and 37.0 yr., respectively (range between 16 and 90 years for smokers and nonsmokers). The mean age of starting to smoke cigarettes was 21.3 yr. (range of 10 to 60). The most common reasons for current cigarette smoking were Need to avoid withdrawal symptoms, Release of tension, and Pleasurable purposes. Foreign filter-tipped cigarettes were the most common type consumed. The mean number of cigarettes per day was 13.4 (SD = 10.3). Reports for onset of cigarette smoking included Modeling, Release of tension, and Pleasurable purposes. Cigarette smoking was reported by more males than females. The most common reason for onset of cigarette smoking was different from that for current smoking. Frequencies of smokers within age groups were varied.

Substance use among Iranian psychiatric inpatients.

This study evaluated substance use among a sample of 205 psychiatric inpatients (70 women and 135 men) chosen randomly. The subjects (who had schizophrenia or mood disorders) were evaluated on a confidential questionnaire by interview. Their mean age was 35 yr. (SD= 10.4, range 16 to 69). Of these participants, 76% of the 135 men and 34% of the 70 women admitted use of substances: cigarettes (74% of men, 31.4% of women), opiates (31.9% of men, 4.3% of women), alcohol (23.7% of men, 4.3% of women), hashish (8.9% of men, no women), marijuana (3.7% of men, no women), and cocaine or LSD by none. Only 27% of the women and 63% of the men reported still using substances regularly; some reported using more than one substance. Of the current users, 61.8% of the schizophrenics, 20% of unipolar depressed, and 37.5% of bipolar patients reported current use. The reasons for substance use in order of frequencies of mention were release of tension, seeking pleasure, and need (to avoid withdrawal symptoms) by men and habit, seeking pleasure, and need by women.

Fungal infections of the central nervous system.

The diagnosis and treatment of central nervous system fungal infections typically pose problems for the clinician. With an increased incidence of fungal infections in immunocompromised patients, neuroradiologic imaging has become essential in determining complications and outcomes. This article provides a summary of the more common organisms encountered in fungal infections of the central nervous system and the imaging features primarily seen with CT and MR imaging.

Sinusitis and carotid artery stroke.

The relationship between sinusitis and ischemic stroke is unexplored. The anatomic proximity between the paranasal sinuses and the internal carotid artery suggests that inflammation of the sinuses could easily extend to the intracranial vasculature. We report 4 patients with acute ischemic stroke and extensive disease of the paranasal sinuses. All patients had large vessel stroke involving the internal carotid artery territory. All patients had extensive disease of the sphenoid and other sinuses. The sinus disease was demonstrated by magnetic resonance imaging. These case report observations suggest a relationship between inflammation of the paranasal sinuses, particularly sphenoid sinusitis, and ischemic stroke.