Biomedical subjects

E Räsänen

Publications and source records attributed to E Räsänen.

At least 19 recordsLinked to original sources

PubMed2006

Half-integer filling-factor states in quantum dots.

The emergence of half-integer filling-factor states, such as upsilon=5/2 and 7/2, is found in quantum dots by using numerical many-electron methods. These states have interesting similarities and differences with their counterstates found in the two-dimensional electron gas. The upsilon=1/2 states in quantum dots are shown to have high overlaps with the composite fermion states. The lower overlap of the Pfaffian state indicates that electrons might not be paired in quantum dot geometry. The predicted upsilon=5/2 state has a high spin polarization, which may have an impact on the spin transport through quantum dot devices.

Journal Article↗

PubMed2004

Determination of tackiness of chitosan film-coated pellets exploiting minimum fluidization velocity.

The tackiness of aqueous chitosan film coatings and effects of anti-sticking agents on sticking tendency, were evaluated. A novel rapid method exploiting minimum fluidization velocity to determine tackiness was introduced and tested. The pressure difference over the miniaturized fluidized-bed was precisely recorded as a function of velocity of fluidization air. High molecular weight chitosan plasticized with glycerol was used as a film-forming agent. Magnesium stearate, titanium dioxide, colloidal silicon dioxide and glyceryl-1-monostearate (GMS) were studied as anti-sticking agents. Film coatings were performed in a miniaturized top-spray coater. The incorporation of anti-sticking agents led to a clear decrease in tackiness of the chitosan films, and magnesium stearate and GMS were shown the most effective. Film-coated pellets containing magnesium stearate and GMS as an anti-sticking agent were very easily fluidized (showing very low values of minimum fluidization velocity) and were thus classified as the best flowing and the least sticking samples. Both these additives were found anti-sticking agents of choice for aqueous chitosan film coatings. Determination of the experimental minimum fluidization velocity in a fluidized bed, is a useful and sensitive method of measuring the tackiness tendency of film-coated pellets.

Adhesiveness↗

PubMed2002

Poor sleep and psychiatric symptoms at school: an epidemiological study.

The objective of this study was to evaluate associations between sleep problems and psychiatric symptoms at school. A random sample consisting of 5813 eight- to nine-year-old children was selected from ordinary schools. Both parents' and children's reports of sleep problems were taken into account. The psychiatric symptoms were addressed according to the teachers' reports (the Rutter Scale B). Children with severe sleep problems were more likely to have a psychiatric disturbance according to the Rutter B Scale (OR 2.45, 95% CI 1.85-3.25). Logistic regression models showed that severe sleep problems were highly associated with emotional problems (OR 2.74, 95% CI 1.84-4.13), school attendance problems (OR 2.53, 95% OR 1.45-4.41), behavioural problems (OR 2.44, 95% CI 1.59-3.75) and hyperactivity (OR 2.02, 95% CI 1.30-3.13). Over 95% of severe sleep problems were reported only by the children themselves. In conclusion, children with severe sleep problems have substantially more teacher-reported psychiatric symptoms than those with no or mild sleep complaints. In diagnosing sleep disorders, it is important to include children as informants because relevant information may be overlooked when only parents are questioned.

Child↗

PubMed2001

Process analysis of fluidized bed granulation.

This study assesses the fluidized bed granulation process for the optimization of a model formulation using in-line near-infrared (NIR) spectroscopy for moisture determination. The granulation process was analyzed using an automated granulator and optimization of the verapamil hydrochloride formulation was performed using a mixture design. The NIR setup with a fixed wavelength detector was applied for moisture measurement. Information from other process measurements, temperature difference between process inlet air and granules (T(diff)), and water content of process air (AH), was also analyzed. The application of in-line NIR provided information related to the amount of water throughout the whole granulation process. This information combined with trend charts of T(diff) and AH enabled the analysis of the different process phases. By this means, we can obtain in-line documentation from all the steps of the processing. The choice of the excipient affected the nature of the solid-water interactions; this resulted in varying process times. NIR moisture measurement combined with temperature and humidity measurements provides a tool for the control of water during fluid bed granulation.

Excipients↗

PubMed2001

Intra-familial child homicide in Finland 1970-1994: incidence, causes of death and demographic characteristics.

The purpose of this study was to investigate all child homicides for the 25-year period, 1970-1994 in Finland and to analyse the specific characteristics of the filicide cases. A total of 292 child homicides occurred during this period. In 201 (69%) cases the offender was a parent or a stepparent of the child. Altogether, 173 (59%) of the victims were boys and 119 (41%) were girls. For the closer examination of the filicide cases we excluded the neonaticide and homicide-suicide cases. Consequently, we report on 70 filicide victims. Of these victims, 42 (60%) were boys and 28 (40%) were girls. Twenty six (37%) of the children were killed before the age of 1 year and 53 (79%) before the age of 5 years. The offender was the mother in 43 (61%) cases and the father or the stepfather in 26 (37%) cases. The victims of the mothers were younger than those of the fathers. The most frequent causes of death were head injuries, drowning and suffocation. The most common means of assault were battering, drowning and strangulation. One in two of the fatally battered children had a documented history of previous abuse.

Adolescent↗

PubMed2001

Novel identification of pseudopolymorphic changes of theophylline during wet granulation using near infrared spectroscopy.

The purpose of this study was to demonstrate the efficiency of near infrared (NIR) spectroscopy in studying the pseudopolymorphic changes and the state of water during the wet granulation process. Anhydrous theophylline was granulated in a planetary mixer using water as granulation liquid. NIR spectra and differential scanning calorimetric (DSC) and wide-angle X-ray scattering (WAXS) patterns of theophylline granules, anhydrous theophylline, and theophylline monohydrate were measured. At a low level of granulation liquid (0.3 mol of water per mole of anhydrous theophylline), water absorption maxima in the NIR region occurred first at around 1475 and 1970 nm. These absorption maxima were identical to those of theophylline monohydrate. At higher levels of granulation liquid (1.3-2.7 mol of water per mole of anhydrous theophylline), the increasing absorption maxima occurred at 1410 and 1905 nm due to OH vibrations of free water molecules. X-ray diffraction patterns confirmed the transformation of anhydrous theophylline to theophylline monohydrate during wet granulation. NIR spectroscopy was able to detect different states of water molecules during the wet granulation process faster and in a more flexible manner than conventional methods.

Calorimetry, Differential Scanning↗

PubMed2001

Somatically expressed psychological distress and alexithymia in adolescence--reflecting unbearable emotions?

The characteristics of five 11- to 15-year-old patients with somatic symptoms and alexithymia in conjunction with psychological distress are reported. The findings are compared with the existing literature. Preceding somatic disorders and difficulties at school and in peer relationships were found. Family violence was evident in two cases. We postulate that the developmental tasks of adolescence were complicated by the threat of disability, disease, and death. The parents were incapable of expressing their feelings either in general or because of their recent traumatic experiences. Our findings suggest that unbearable emotions often precede the combination of preadolescent and adolescent alexithymia and somatization in clinically relevant cases.

Adolescent↗

PubMed2001

Characterization of wet massing behavior of silicified microcrystalline cellulose and alpha-lactose monohydrate using near-infrared spectroscopy.

The purpose of this study was to investigate the energetic state of water in silicified microcrystalline cellulose (SMCC) and alpha-lactose monohydrate wet masses using near-infrared (NIR) spectroscopy. The applicability of NIR spectroscopy to studying pharmaceutical wet masses at a wide moisture range was evaluated in comparison with mixer torque rheometry (MTR). With increasing moisture content changes in the physical properties of the samples resulted in an apparent increase in log (1/R) throughout the whole spectrum. The upward displacement of baseline and the relative height of water bands were greatest with materials that had a poor liquid-retention capacity. In the case of SMCC and 1:1 mixture of SMCC and alpha-lactose monohydrate, the height of the baseline-corrected water bands increased linearly at low moisture contents, thereafter achieving a plateau stage. According to the MTR results, the plateau stage of the band heights indicated a capillary state of liquid saturation. The second derivative spectrum was capable of distinguishing monohydrate, absorbed, and adsorbed water, which overlapped in the absorbance spectrum. When water was absorbed to the internal structure of the material (SMCC), the water bands were first seen at higher wavelengths, then followed by a shift to lower wavelengths. When water was only adsorbed onto the surface of the particles (glass ballotini), the water bands were seen directly in the region of bulk water.

Crystallization↗

PubMed2000

The persistence of psychiatric deviance from the age of 8 to the age of 15 years.

BACKGROUND: Earlier research has shown that psychiatric problems in children tend to persist over years. This investigation assessed the persistence of psychiatric deviance among children over a 7-year period from the age of 8 to the age of 15 years. We also explored the relationship between problems leading to special attention at the well-baby clinics before school age and future psychiatric deviance. METHODS: The study material consisted of three questionnaires filled out by the parents, teachers and children themselves (N = 1268) at three time points, together with data concerning the children gathered from the records of well-baby clinics. RESULTS: At the age of 15 years, girls scored higher than boys on the parental scale and on the Beck's Depression Inventory (BDI), while boys scored higher than girls on the teachers' scale. Parental ratings had a high correlation over 3 years and a moderate correlation over 7 years. Teachers' and children's ratings correlated moderately over 3 years, but did not correlate significantly over 7 years. The probability of being deviant at the age of 15 years was elevated if the child scored high on the parents' or teachers' scale at the age of 8 or 12 years, or on the Children's Depression Inventory (CDI) at the age of 12 years. Problems noted by health professionals (problems in growth, somatic diseases, emotional/behavioural problems of the child, psychosocial problems of the family) before school age were related to future deviance on the parental scale. Emotional/behavioural problems before school age elevated the probability of scoring high on the teachers' scale at the age of 15, and problems in psychomotor development elevated the probability of scoring high on the BDI. CONCLUSIONS: Psychiatric deviance is persistent over several years in children. Primary health care professionals can identify children who are at risk for future psychiatric problems.

Adolescent↗

PubMed2000

Children involved in bullying at elementary school age: their psychiatric symptoms and deviance in adolescence. An epidemiological sample.

OBJECTIVE: This study investigated psychiatric symptoms and deviance at the age of 15 years among children involved in bullying at the age of 8 years or at the age of 12 years. Furthermore, the relationships between involvement in bullying at the age of 8 years, concurrent psychiatric deviance, and later psychiatric deviance were studied. METHOD: Questionnaires filled in by the parents, teachers and children themselves were used to reveal psychiatric symptoms and deviance. RESULTS: Children involved in bullying, in particular those who were bully-victims at early elementary school age and those who were victims in their early teens, had more psychiatric symptoms at the age of 15 years. The probability of being deviant at the age of 15 years was higher among children involved in bullying at the age of 8 or 12 years than among non-involved children. When concurrent psychiatric deviance was taken into account, involvement in bullying increased the probability of teacher-defined deviance at the age of 15 years. CONCLUSION: Bullying experiences are connected not only to concurrent psychiatric symptoms but also to future psychiatric symptoms. Furthermore, the probability of being deviant in adolescence is increased if the child has been involved in bullying at elementary school age.

Adolescent↗

PubMed2000

In-line moisture measurement during granulation with a four-wavelength near infrared sensor: an evaluation of particle size and binder effects.

Factors affecting in-line near infrared (NIR) moisture measurement with a four-wavelength sensor were evaluated (choice of binder used in granulation liquid and the increase in particle size). An entire NIR spectrum is not necessary for the measurement of water, and often the use of only a few NIR wavelengths around the water band enables reliable and high-speed detection of moisture. Glass ballotini and microcrystalline cellulose (MCC) were used as model test materials. The binders studied were poly[1-(2-oxo-1-pyrrolidinyl)ethylene] (PVP) and gelatin. Full off-line NIR spectra of test materials at different levels of binder solutions were measured. The major spectral features for both the binders were bands around 1700 nm (first overtones CH related stretches) and 2200 nm (combination bands). Gelatin also had an NH band around 1500 nm (first overtones of NH stretches) and combination bands at about 2050 nm. Particle size effects were observed as an increase in spectra baseline. All these factors should be considered when choosing NIR wavelengths used for detection of water with a fixed wavelength set-up. A robust calibration model enables the development of in-process control of wet granulation processes.

Calibration↗

PubMed2000

Sleep problems of school-aged children: a complementary view.

The aim of this population-based multicentre study was to evaluate the prevalence rates of sleep problems among 8-9-y-old children. The sample consisted of 5813 Finnish children, making up 10% of the age cohort. Both parents and children provided information. Disturbed sleep was reported by 21.7% of parents. Most of the problems were mild; only 0.3% were serious. Dyssomnias were frequent: 11.1% had difficulties with sleep onset, 7.1% with night waking and 2.3% with waking too early. Multiple sleep problems were present in 9.1% of the children. 17.8% of children reported disturbed sleep, 12.7% had problems many nights and 5.1% every night. In 32.0% of cases, either the parent or the child reported disturbed sleep; 7.4% of these reports came from both the parent and the child, 14.1% from the parent only and 10.3% from the child only. The correspondence between informants was poor (kappa = 0.224). Sleeping problems were associated with somatic and psychiatric problems. It is concluded that by restricting questioning to parents only, one-third of all potential cases of sleep problems may go unnoticed. In order to increase the sensitivity of screening children's sleep problems, both parents and children should provide information in epidemiological settings as well as in clinical work.

Chi-Square Distribution↗

PubMed1999

Design and subjects of a Finnish epidemiological study on psychiatric disorders in childhood.

In an epidemiological multi-centre study, parents filled in the Rutter Parent Questionnaire (RA2) and teachers filled in the Rutter Teacher Questionnaire (RB2) for almost 6000 children. The children filled in the Children's Depression Inventory (CDI). The subjects well represented the entire population of 8-9-year-old children in Finland. The material and design of the study as well as the basic demographic characteristics are presented.

Catchment Area, Health↗

PubMed1999

Behavioural and emotional symptoms in 8-9-year-old children.

We present epidemiological data from a multi-centre study on psychiatric symptoms among 6017 8-9-year-old children representing a total annual birth cohort (N = 60007) in Finland. The results are based on three questionnaires: the Rutter Parent Scale (RA2), the Rutter Teacher Scale (RB2), the Children's Depression Inventory (CDI). The proportion of children that scored above the cutoff points, indicating probable psychiatric disturbance, were 11.2% for the RA2, 13.9% for the RB2 and 6.9% for the CDI. Twenty-four percent of the subjects scored above the cutoff point on at least one of the questionnaires. Low family social status and disrupted family relations correlated strongly with high rates of symptoms in the children.

Child↗

PubMed1999

Psychiatric disorders in 8-9-year-old children based on a diagnostic interview with the parents.

Using three questionnaires, the Rutter Parent Questionnaire (RA2), The Rutter Teacher Questionnaire (RB2) and the Children's Depression Inventory (CDI), we screened 8-9-year-old children representing a total annual birth cohort (N = 60007) in Finland. In a second stage we interviewed the parents of 119 screen negative, and 316 screen positive children by using a structured parent interview. At the population level the overall prevalence rate for psychiatric disturbance was 21.8%, higher among boys (29.8%) than among girls (12.8%). Nine percent of the children were in urgent need of treatment and, in addition, 25% were in need of assessment. The prevalence of different levels of disturbance was: reactive 9.5%; neurotic 18.4%; borderline 3.1%; and other severe disorders 2.3%. The prevalence of different diagnostic groups were: anxiety disorder 5.2%; depressive disorder 6.2%; specific fears 2.4%; defiant and conduct disorder 4.7%; and attention-deficit hyperactivity-disorder 7.1%. The prevalence for the most common single first Axis-I DSM-III-R diagnoses were: attention-deficit hyperactivity-disorder 7%; dysthymia 4.6%; adjustment disorder with mixed disturbance of emotion and conduct 3.4%; oppositional defiant disorder 2.7%; specific fear 1.7%; anxiety disorder 1.5%; enuresis nocturnal 1.5%; and depression 1.4%. Only 3.1% of the children had visited health professionals for psychiatric problems during the previous three months. Only a minority of the children with psychiatric disturbances had ever consulted health professionals for their problems. Of all the children, 7.5% had a severe psychiatric disturbance that had lasted for more than 3 years.

Child↗

PubMed1999

Psychiatric disorders, performance level at school and special education at early elementary school age.

We assessed the relationship between psychological deviance and performance level at school among 8-year-old children. The use of special education among children with psychiatric disorders was also studied. In Stage 1, 5813 children were studied using the Rutter Parent Questionnaire (RA2), the Rutter Teacher Questionnaire (RB2) and the Children's Depression Inventory (CDI). In Stage 2, a subsample (n = 424) of these children were interviewed, using the Isle of Wight Interview. In Stage 1, more children defined as low achievers (LAs) came from low SES families than did average (NAs) and high achievers (HAs). They also had more psychiatric symptoms, and they scored above the cutoff (13 points on the RA2, nine points on the RB2 and 17 points on the CDI) more commonly than other children. In Stage 2, two thirds of children who received special education had some psychiatric disorder. The probability of a child with psychiatric disorder obtaining some extra tutoring or special education was 3.1-fold when compared with children without psychiatric disorders. Depressive children and children with attention deficit disorders most commonly had extra tutoring (4.8-fold) when compared with children without psychiatric disorders. The probability of getting special education was highest for attention deficit disorders (6.2-fold), thereafter for anxiety (3.1-fold), and for oppositional/conduct disorders (2.8-fold).

Achievement↗

PubMed1999

Behavioural/emotional symptoms among 8-9-year-old children with somatic symptoms or illnesses as reported by their teacher.

The aim of this study was to assess children's behavioural/emotional symptoms at school and to compare these symptoms of somatically healthy children with those of children with somatic illnesses or symptoms. The Rutter Teacher Questionnaire (RB2) was used for measuring psychiatric symptoms in 5813 children aged 8-9 years. The parents reported the somatic symptoms and illnesses of their children during the previous 12 months. One hundred and sixty one children had a marked or serious chronic illness, 292 had a mild chronic illness, and 92 had one or several symptoms. The findings suggest that boys with a marked or serious chronic somatic illness are prone to manifest psychiatric symptoms in their interactions with peers and teachers at school and that boys with a mild chronic illness have less psychiatric symptoms than healthy boys.

Child↗

PubMed1999

Smoking and drinking habits in adolescence--links with psychiatric disturbance at the age of 8 years.

Smoking and drinking habits were studied among 1098 14-15-year-old adolescents using a mailed questionnaire. The subjects were drawn from a representative population of 5813 randomly selected 8-year-old children previously studied in the National Epidemiological Child Psychiatry Study in Finland in 1989. The questionnaire included items on the adolescents' smoking habits and alcohol consumption. Regular smoking was more common among boys (and girls) who, in childhood, had been rated by their parents (Rutter Parent Questionnaire) (RA2) as disturbed, 14.6% (30.3%), than among the nondisturbed, 6.6% (8.4%). Similarly, more of the previously disturbed (according to the RA2) adolescent boys drank alcohol regularly, 19.7%, as compared to the nondisturbed boys, 9.3%. Among girls, regular alcohol consumption was more common among those who previously had behavioural or mixed type problems (according to the RA2), 70.7%, as compared to those who previously had emotional or no problems, 12.2%. More of the previously depressed girls smoked regularly, 45.1%, than those who had not been depressed, 7.9%. Behavioural and emotional problems in childhood seemed to predispose to smoking and drinking in adolescence. The parents were more sensitive than the teachers in recognising the long-lasting problems of their children.

Adolescent↗