An influence of temperature jump and Navier's slip-on hybrid nano fluid flow over a permeable stretching/shrinking sheet with heat transfer and inclined MHD.

This research article, explores the influence of an inclined magnetic field on the fluid flow over a permeable stretching/shrinking surface with heat transfer. The study use water as a conventional base fluid, with graphene oxide (GO) and Aluminum oxide (Al2O3) nanoparticles submerged to create a nanofluid, the system of governing nonlinear partial differential equations converted into ordinary differential equations via suitable similarity conversions. This allow for the unique solution for stretching sheet/shrinking sheets to be obtained, along with the corresponding temperature solution in terms of the hypergeometric function, several parameters are included in the investigation and their contribution is graphically explained to examine physical characteristics such as radiation, inclined magnetic field, solution domain, volume fraction parameter, and temperature jump. Increasing the volume fraction and thermal radiation increases the thermal boundary layer, increasing the magnetic field parameter and inverse Darcy number increases the temperature and decays the velocity profile. The present work has many useful applications in engineering, biological and physical sciences, as well as in cleaning engine lubricants and thrust-bearing technologies.

The contact angle of nanofluids as thermophysical property.

Droplet volume and temperature affect contact angle significantly. Phase change heat transfer processes of nanofluids - suspensions containing nanometre-sized particles - can only be modelled properly by understanding these effects. The approach proposed here considers the limiting contact angle of a droplet asymptotically approaching zero-volume as a thermophysical property to characterise nanofluids positioned on a certain substrate under a certain atmosphere. Graphene oxide, alumina, and gold nanoparticles are suspended in deionised water. Within the framework of a round robin test carried out by nine independent European institutes the contact angle of these suspensions on a stainless steel solid substrate is measured with high accuracy. No dependence of nanofluids contact angle of sessile droplets on the measurement device is found. However, the measurements reveal clear differences of the contact angle of nanofluids compared to the pure base fluid. Physically founded correlations of the contact angle in dependency of droplet temperature and volume are obtained from the data. Extrapolating these functions to zero droplet volume delivers the searched limiting contact angle depending only on the temperature. It is for the first time, that this specific parameter, is understood as a characteristic material property of nanofluid droplets placed on a certain substrate under a certain atmosphere. Together with the surface tension it provides the foundation of proper modelling phase change heat transfer processes of nanofluids.

Convective heat transfer on an inlet guide vane.

The flow and temperature fields around an inlet guide vane are determined numerically by a CFD method. Outer surface temperatures, heat transfer coefficient distributions, and static pressure distributions are presented. Three different thermal boundary conditions on the vane are analysed. The computed results are compared with experimental data. The governing equations are solved by a finite-volume method with the low Reynolds number version of the k-omega turbulence model by Wilcox implemented. It is found that the calculated results agree best with measurements if a conjugate heat transfer approach is applied and thus this wall condition is recommended for future investigations of film cooling of guide vanes and turbine blades.

Numerical investigation of combined impingement and convection heat transfer.

This paper concerns development of a prediction method for combined turbulent impingement and convection heat transfer. Firstly, a prediction of a single round unconfined impinging air jet without crossflow is investigated to assess the performance of linear and non-linear two-equation turbulence models. The results show that realizable and/or non-linear two-equation models may successfully be used for impinging jet heat transfer predictions but there are significant differences between the formulations. Among the models tested, a non-linear k-omega showed superior performance. Secondly, the influence of crossflow is considered and a plane confined air jet is investigated. For this case the models based on a frequency-equation (omega) show quite different and more reasonable predictions compared to the dissipation-equation (epsilon) based models.

Temporomandibular disorders: Part II. A comparison of psychologic profiles in Australian and Finnish patients.

Recent recommendations regard musculoskeletal disorders of the masticatory system as dual-axis disorders, but little comparative data of psychologic factors across different pain populations are available. In this study, presenting psychologic profiles were assessed in 40 Australian and 42 Finnish patients diagnosed with temporomandibular disorders. Findings were compared with those of a group of Australian patients reporting acute dental pain and with reference to response to conservative management. The psychologic testing instrument incorporated cognitive, motivational/affective, and illness behavior variables, and it was based on validated general pain questionnaires (Coping Strategies Questionnaire and Illness Behavior Questionnaire). This instrument was found internally reliable in the majority of its subscales in the group studies and provided comparable data to other pain populations. Significant differences in the presenting psychologic profiles were found according to nationality, type of pain suffered, and treatment outcome. Affective disturbance, hypochondriasis, lack of cognitive control, and feeling ill with symptoms were identified in discriminant function analysis as potential predictors of treatment outcome, and they correctly classified 79% of the Australian and 87% of the Finnish patients with temporomandibular disorders. It was concluded that psychologic profiles differed in the two nationalities and were related to treatment outcome. The concept of multiaxial assessment was supported.

Temporomandibular disorders. Part I: A comparison of symptom profiles in Australian and Finnish patients.

Variability in the assessment methods of patients seeking treatment for musculoskeletal disorders of the masticatory system confounds comparative assessment of different studies. In this study, presenting symptom profiles were assessed in 40 Australian and 42 Finnish patients with temporomandibular disorders. The symptom parameters of these patients were compared with those of 40 Australians reporting acute dental pain and were assessed with reference to response to conservative management. A self-administered anamnestic questionnaire was used in a standard, systematic, and comparative way to assess demographic data, general health status, and symptom parameters according to type, frequency, severity, duration, location, impact on the patients' lives, urgency for need of treatment, and possible initiating factors. It was found that the two nationalities studied had similar presentations of cardinal symptom profiles. Statistically significant differences in major presenting symptoms were found between patients with temporomandibular disorders and those with acute dental pain, but not between patients who responded rapidly as opposed to slowly to conservative therapy. It was concluded that the presenting symptom profiles were similar for the two nationalities and were not related to treatment outcome.

Assessment of patients suffering from chronic orofacial pain of nonspecific origin.

The diagnosis and assessment of patients suffering from chronic, persistent orofacial pain of nonspecific origin can be difficult because of the interactions between psychological and somatic signs. Patients with chronic pain are treated differently from those with acute pain and often fail to respond to the usual acute pain model. This article discusses the practical assessment and drug treatment of chronic orofacial pain of nonspecific origin.

Experiences from a facial pain unit.

During the academic year 1988/1989, 282 patients with chronic orofacial pain were referred to the facial pain unit of the University of Helsinki; 143 of these patients were suffering mainly of orofacial dysesthesia and 139 patients of masticatory dysfunction. Thirty-six of the patients with orofacial dysesthesia were referred for a psychiatric consultation. The result revealed a strong mental disturbance component associated with this kind of pain disorder. The patients with orofacial dysesthesia were treated mostly with amitriptyline, clonazepam, and distigmin; the patients with masticatory dysfunction were treated with splints and/or occlusal rehabilitation.

Ultrasound measurement of the ovarian volume.

The ovaries of 377 women between the age of 40 and 70 years were measured by ultrasound. About one third of the patients were postmenopausal. Mean value, standard deviation and S.E.M. of the ovarian volume were calculated and related to age, parity and menstrual cycle. Ovarian size decreased with age in all women but bore no relation to parity and day of menstrual cycle in the menstruating group of women over 40 years of age. A diagram of the ovarian volume related to age is presented. In postmenopausal women the volume was related to estrogen treatment, age, parity and years since menopause. In the group of women receiving orally administered estrogens for at least a year the p-values for all parameters were greater than 0.005. Furthermore, the ovarian volume of women under hormonal treatment did not decrease with age. On the other hand the most important factor for ovarian size in subjects not receiving estrogen treatment was age (p = 0.0056). The results presented here will serve as a prerequisite for sonar examination of the ovaries in women at high risk for development of ovarian carcinoma.

Diagnostic ultrasound in threatened abortion and suspected ectopic pregnancy.

200 women threatened with abortion during the first 16 weeks of pregnancy were examined with diagnostic ultrasound to determine whether there were signs of intrauterine life. Of the 90 who showed positive signs, 8 aborted spontaneously later, the other 82 continued their pregnancy. The ultrasound investigation revealed no signs of intrauterine life in 110 patients. Of these, spontaneous abortion or later evacuation because of missed abortion 101 (histopathological examination showed degenerated villi in 98), not pregnant 4, mola hydatidosa 3, extrauterine pregnancies 2. An ultrasound examination was performed to ascertain whether 136 women with suspected ectopic pregnancy had intrauterine pregnancies. 61 of them had an intrauterine gestational sac, confirmed at clinical follow-up. One of the 61 was operated on with laparoscopy because of pain; no abnormalities were found. In 36 of the other 75, laparoscopy was performed. Ectopic pregnancy 21, ovarian or parovarian cyst 11, adhesions 2, salpingitis 1, and normal 1. Diagnostic ultrasound is excellent for accurate prognosis in threatened abortion. Unnecessary operations avoided; hospitalization in suspected ectopic pregnancies reduced.

Neonatal and prospective follow-up study of infants delivered by vacuum extraction (VE).

Forty infants delivered by vacuum extraction have been studied in the neonatal period--neurological examination, neonatal CSF-examinations, skull X-ray examination, transillumination and sonoencephalography --and at 14 months of age--developmental and behavioural evaluation, neurological examination, skull X-ray examination, sonoencephalography and electroencephalography. Two infants died in the neonatal period but in both cases a life-threatening situation of the fetus required immediate delivery. CSF cytological signs of haemorrhage were observed in 42% of the 26 infants who had a successful lumbar tap, compared to 10% found in normal deliveries. The result of the neonatal neurological study did not differ from that in a control group. The result of the skull X-ray examination and sonoencephalography were also within normal limits. In the follow-up study behavioural problems were found in 25%, but otherwise very few abnormalities were found. The deviatiosn found do not for the present indicate any later signs of brain lesions. It is concluded that this prospective study has shown that VE-delivery in fullterm babies seem to imply no risk fo serious cerebral sequelae. Further follow-up studies at a later age in order to evaluate the incidence of so-called minimal brain damage in VE-delivered children are required.