Home About us Contact
|
Home About us Contact | ||
|
|
||
Preliminary Study (preliminary + study)
Selected AbstractsDISORDER WITH LAW: A PRELIMINARY STUDY OF VIOLENCE IN RESPONSE TO WATER RIGHTS VIOLATION IN COLONIAL NEW SOUTH WALESECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 2 2008EDWYNA HARRIS Scholars argue that violence will not occur in the presence of efficient property rights institutions. Empirical evidence from the Riverina district in New South Wales between 1855 and 1870 contradicts this claim. This paper provides a preliminary analysis of evidence to explain this apparent inconsistency. Violence was directed at upstream users who dammed rivers, preventing flow to downstream users. Evidence suggests violence was a form of social control referred to as self-help employed to enforce conventions of fairness. Dams were perceived as unfair because they reduced the distributive equity embodied in the common law of riparian rights that established water-use rules to allocate water between competing users. Violence in the form of dam destruction occurred primarily during drought years and was the preferred over common law remedies because of the lag time between seeking court intervention and obtaining a remedy. Coasean bargaining was not possible because of high transaction costs. The findings suggest that violence may occur in the presence of efficient property rights institutions if actors violate conventions of fairness. Violence may be more likely if property rights themselves embody these conventions. [source] Gross and Microscopic Findings in Patients Submitted to Nonablative Full-Face Resurfacing Using Intense Pulsed Light: A Preliminary StudyDERMATOLOGIC SURGERY, Issue 8 2002Enrique Hernández-Pérez MD background. Intense pulsed light (IPL) is a noncoherent, nonlaser, filtered flashlamp emitting a broadband visible light that has been shown to be effective in photoepilation, as well as in a number of vascular and pigmented lesions of the skin. Their efficacy has also been reported recently in the treatment of photodamaged facial skin. In the last condition, however, there are few studies showing the clinical and microscopic changes produced by IPL. objective. To assess the gross and microscopic changes that occur in photodamaged skin submitted to nonablative full-face resurfacing (NAFFR) using IPL. methods. Five women were submitted to five NAFFR sessions using IPL, one every 2 weeks. Skin biopsies and photographs were taken on all of the patients before the first procedure and after the last one, as well as weekly clinical assessment. Data concerning skin features (wrinkles, oiliness, thickness, dilated pores, and general appearance) were all assessed. Microscopic improvement of the aging features in the epidermis and dermis were all assessed. For the statistical analysis a t test for small samples was used. results. All the patients showed clinical and microscopic improvement in every one of the parameters assessed. The t test for small samples showed a statistically significant difference (P < 0.01) in epidermal thickness. conclusion. Facial photodamage was clinically and microscopically improved using IPL. Use of IPL as a rejuvenating method seems to be promising, with minimal side effects, a wide safety margin, and minimal downtime. [source] Adrenal Insufficiency in Critically Ill Emergency Department Patients: A Taiwan Preliminary StudyACADEMIC EMERGENCY MEDICINE, Issue 7 2001Shy-Shin Chang MD Objective: Unrecognized adrenal insufficiency can have serious consequences in critically ill emergency department (ED) patients. This prospective pilot study of adrenal function in patients with severe illness was undertaken to determine the prevalence of adrenal dysfunction and any relation to prior herbal drug use. Methods: In a high-volume urban tertiary care ED, adult patients with sepsis or acute myocardial infarction (AMI) were eligible for the study. Over a two-month period, a convenience sample was enrolled by the authors on arrival to the ED. Inclusion criteria were systemic inflammatory response syndrome (SIRS) criteria plus evidence of at least one organ dysfunction or cardiac marker plus electrocardiogram-proven AMI. Exclusion criteria included known corticosteroid use. Serum cortisol was measured on arrival and for those patients with a level of <15 ,g/dL (<414 nmol/L), an adrenocorticotropic hormone (ACTH) stimulation test was performed. Results: Of the 30 enrolled patients, 23 (77%) were suffering from severe sepsis and the other seven (23%) had an AMI. Thirteen of the 30 patients (43%; 95% CI = 25% to 65%) had serum cortisol levels of <15 ,g/dL, consistent with adrenal insufficiency, nine with severe sepsis and four with an AMI. Eight (62%; 95% CI = 32% to 86%) of the 13 patients with low cortisol levels reported using herbal medications, while only two (12%; 95% CI = 1% to 36%) of the 17 with normal cortisol levels reported taking herb drugs (p = 0.01). Only two (15%; 95% CI = 2% to 45%) of the patients with low cortisol levels failed their corticotropin stimulation test, suggestive of true adrenocortical insufficiency. Both reported using herbal preparations. Conclusions: These results indicate that adrenal dysfunction is common among a group of critically ill patients seen in this Taiwanese ED. Moreover, the use of herbal drugs was high in the patients with low serum cortisols. Further studies are required to both confirm these findings and clarify whether a number of herbal medications contain corticosteroids. [source] Taphonomic Changes to Blunt Force Trauma: A Preliminary Study,JOURNAL OF FORENSIC SCIENCES, Issue 3 2007Stephanie E. Calce B.Sc. Abstract: This study examines the effects of taphonomic processes on blunt force trauma (BFT) through an experimental study involving pig heads. Of particular concern is the possibility that taphonomic changes can create pseudo-trauma and/or conceal evidence of actual trauma. BFT was inflicted on 10 pig skulls using a hammer. The skulls were subsequently exposed to the environment for 12 months. Seven taphonomic changes were evaluated: the freeze,thaw cycle; rodent gnawing; carnivore scavenging; presence/weight of soil; presence/weight of rain and snow; movement/displacement of bones; and discoloration due to sun bleaching and grass staining. Taphonomic effects varied between cancellous, compact, fresh, and degreased bone. Freezing and thawing, exposure to rain and snow, movement of the skulls, and soil erosion altered and, in some cases disguised, pre-existing trauma. Rodent and carnivore activity did not obliterate evidence of BFT. Recommendations for evaluating BFT on remains affected by taphonomic processes are presented. As each taphonomic process outlined by this study has the potential to disguise antemortem injury, the authors propose that one must carefully examine large, circular openings in the skull that may represent the remnant evidence of BFT. [source] The Effect of a Constant Electrical Field on Osseointegration after Immediate Implantation in Dog Mandibles: A Preliminary StudyJOURNAL OF PROSTHODONTICS, Issue 5 2007Yadollah Soleymani Shayesteh DDS Purpose: The long time span between insertion of implants and functional rehabilitation often inconveniences patients. Accelerating bone growth around dental implants can shorten this time span. This in vivo study evaluated the effect of a constant electrical field on bone growth around dental implants. Materials and Methods: Four mongrel dogs were used in this study. Sixteen dental implants were placed immediately after extraction of the first premolar and molar teeth. A constant electrical field (CEF) generator was placed in the mucoperiostal pouch created from the subperiostral dissection under the inferior border of the dog's mandible and connected to the experiment side fixtures. CEF provided 3 V of electrical potential during osseointegration. Histologic sections were stained with hematoxylin,eosin and observed under light microscopy. The sections were analyzed histomorphometrically to calculate the amount of newly formed bone. Statistical analysis was performed with SPSS 11.0 computer software (,= 0.05). Results: At the end of the first stage of the osseointegration (90 days) CEF group sections showed enhanced growth of the trabeculae compared with the control group. Statistical analysis revealed significant differences between experimental and control groups. Bone contact ratio was statistically significant in the experimental group (p= 0.001). An increase in the local bone formation and bone contact ratio was observed with direct electrical stimulation of the implant and the bone area around the implant. Conclusion: Minimal direct electrical current, which can produce an electrical field around the implant, can increase the amount of bone formation and decrease the time of osseointegration. [source] The Use of Radial Extracorporeal Shockwave Therapy in the Treatment of Urethral Urolithiasis in the Horse: A Preliminary StudyJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2008D. Verwilghen Background: Radial extracorporeal shockwave therapy (ESWT) is widely used in equine practice for the treatment of orthopedic problems. However, its original use as a lithotripsy device in human and canine urology led us to postulate that it could be used as an alternative to the surgical treatment of urethral calculi in horses. Hypothesis: Radial ESWT can easily and safely fragment calculi in the distal urethra of the horse. Animals: Two postmortem cases and 1 live case of obstructive urinary disease admitted at the Veterinary Teaching Hospital of Liege. Methods: A radial shockwave device was directly applied to the urethra in an attempt to fragment calculi. An ex vivo trial was performed on the same retrieved calculi to investigate pressure settings in order to obtain complete fragmentation of the calculus. Results: In all cases, radial ESWT was able to fragment the calculus partially, enabling retrieval of the remaining fragments via the urethra. Much higher pressure settings than those used for in vivo partial fragmentation were necessary to obtain complete destruction of the calculi ex vivo. Conclusions and Clinical Importance: This brief report suggests the use of radial ESWT as a safe and useful alternative to more invasive surgical management of urethral calculi in horses. [source] A Demonstration of a Presurgical Behavioral Medicine Evaluation for Categorizing Patients for Implantable Therapies: A Preliminary StudyNEUROMODULATION, Issue 4 2008Kimberly Gardner Schocket PhD ABSTRACT Objectives., The aim of the current study was to evaluate the potential efficacy of a presurgical behavioral medicine evaluation screening algorithm with patients undergoing evaluation for implantable pain management devices. Methods., Sixty patients were evaluated for prognostic recommendations regarding outcomes from surgery for spinal cord stimulators and intrathecal pumps. Diagnostic interviews, review of medical charts, and psychosocial and functional measures were used in the initial evaluation. Results., Patients were classified into one of four prognostic groups, from low to increasing risks: Green, Yellow I, Yellow II, and Red. The Green group showed the most positive biopsychosocial profile, while the Red groups showed the worst profiles. Conclusions., This preliminary study suggests that the presurgical behavioral medicine evaluation algorithm may be an effective method for categorizing patients into prognostic groups. Psychological and adverse clinical features appear to have the most power in the classification of such patients. [source] Preliminary Study of the Efficacy of Radiofrequency Lesions of Stellate Ganglion in Chronic Pain PatientsPAIN MEDICINE, Issue 1 2010Shinobu Yamaguchi MD No abstract is available for this article. [source] A Preliminary Study of Solid Embryonic Cerebellar Graft Survival in Adult B6CBA Lurcher Mutant and Wild Type MiceTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 12 2009Jan Cendelín Abstract Lurcher mutant mice represent a model of olivocerebellar degeneration. They suffer from complete loss of Purkinje cells and a reduction of granule cells and inferior olive neurons. Their wild type littermates serve as healthy controls. The aim of the work was to compare solid embryonic cerebellar graft survival within a period of 9 weeks after their transplantation in adult Lurcher mutant and wild type mice of the B6CBA strain. The solid grafts were injected through a hole in the occipital bone. Host mice were sacrificed 3, 6, or 9 weeks after the transplantation and their cerebella and brain-stems were examined histologically to assess graft presence and structure. We did not find significant differences in graft survival rates between Lurcher mutant and wild type mice. The frequency of graft presence did not differ between mice examined 3, 6, and 9 weeks after the transplantation, neither in Lurchers nor in wild type mice. The grafts were of various sizes. In some cases, only small residua of the grafts were found. Nerve fiber sprouting and cell migration from the graft to the host tissue were observed more often in wild type mice than in Lurchers when examined 6 weeks after surgery. In the period 3,9 weeks after transplantation, massive dying out of the grafts was not observed despite regressive processes in some of the grafts. The degenerative changes in the Lurcher mutant cerebellum do not have strong impact on the fate of the solid cerebellar graft. Anat Rec, 292:1986,1992, 2009. © 2009 Wiley-Liss, Inc. [source] Distribution of Cryptosporidium Species and Subtypes in Water Samples in Portugal: A Preliminary StudyTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2006MARGARIDA ALVES [source] A Preliminary Study on Fluid Inclusions and Mineralization of Xitieshan Sedimentary-Exhalative (SEDEX) Lead-Zinc DepositACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2008WANG Lijuan Abstract The Xitieshan lead-zinc deposit is located at the northern margin of the Qaidam Basin, Qinghai Province, China, and had developed a complete marine sedimentary-exhalative system. Our preliminary study of ore-forming fluids shows that fluid inclusions in quartz from altered stockwork rocks that represent the pipe facies have a wide range of temperature and salinity. The intense fluid activities are characteristics of the pipe facies of the exhalative system. Fluid inclusions in carbonates near the unstratified ore bodies hosted in the thick-bedded marble which represents vent-proximal facies are large in size and have moderate to high temperatures. They represent unerupted sub-seafloor fluid activity. Fluids in altered stockwork rocks and carbonates have similar H2O-NaCl-CO2 system, both belonging to the sedimentary-exhalative system. The fluids migrate from the pipe facies to the unstratified ore bodies. Boiling of the fluids causes the separation of CO2 vapor and liquid H2O. When the fluids migrate into the unconsolidated thick-bedded marble, the escape of CO2, decreasing temperature and pressure as well as some involvement of seawater into the fluids result in the unmixing of fluids with high and low salinity and deposition of ore-forming materials. The two unmixed fluids were trapped in unconsolidated carbonates and the ore-forming materials were deposited in the unconsolidated carbonates to form the sedimentary-exhalative type unstratified ore bodies. The ore-forming temperature of unstratified ore bodies is up to high temperature indicating that there is a huge ore-forming potential in its deep. [source] A Preliminary Study of the Gas Hydrate Stability Zone in the South China SeaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2002JIN Chunshuang Abstract, Based on the analysis of sea-bottom temperature and geothermal gradient, and by means of the phase boundary curve of gas hydrate and the sea-bottom temperature versus water depth curve in the South China Sea, this paper studies the temperature and pressure conditions for gas hydrate to keep stable. In a marine environment, methane hydrate keeps stable at water depths greater than 550 m in the South China Sea. Further, the thickness of the gas hydrate stability zone in the South China Sea was calculated by using the phase boundary curve and temperature-depth equations. The result shows that gas hydrate have a better perspective in the southeast of the Dongsha Islands, the northeast of the Xisha Islands and the north of the Nansha Islands for thicker stability zones. [source] Sinus Lift Using a Nanocrystalline Hydroxyapatite Silica Gel in Severely Resorbed Maxillae: Histological Preliminary StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2009Luigi Canullo DDS ABSTRACT Purpose: The aim of this preliminary study was to evaluate histologically a nanocrystalline hydroxyapatite silica gel in maxillary sinus floor grafting in severely resorbed maxillae. Materials and Methods: A total of 16 consecutive patients scheduled for sinus lift were recruited during this study. Patients were randomly divided in two groups, eight patients each. In both groups, preoperative residual bone level ranged between 1 and 3 mm (mean value of 2.03 mm). No membrane was used to occlude the buccal window. Second surgery was carried out after a healing period of 3 months in Group 1 and 6 months in Group 2. Using a trephine bur, one bone specimen was harvested from each augmented sinus and underwent histological and histomorphometric analysis. Results: Histological analysis showed significant new bone formation and remodeling of the grafted material. In the cores obtained at 6 months, regenerated bone, residual NanoBone, and bone marrow occupied respectively 48 ± 4.63%, 28 ± 5.33%, and 24 ± 7.23% of the grafted volume. In the specimens taken 3 months after grafting, mean new bone was 8 ± 3.34%, mean NanoBone was 45 ± 5.10%, and mean bone marrow was 47 ± 6.81% of the bioptical volume. Conclusions: Within the limits of this preliminary prospective study, it was concluded that grafting of maxillary sinus using nanostructured hydroxyapatite silica gel as only bone filler is a reliable procedure also in critical anatomic conditions and after early healing period. [source] Use of a 3D dynamometric horseshoe to assess the effects of an all-weather waxed track and a crushed sand track at high speed trot: Preliminary studyEQUINE VETERINARY JOURNAL, Issue 3 2009D. Robin Summary Reasons for performing study: Track surface quality is considered a risk factor of musculoskeletal injuries. Ground reaction force (GRF) measurement is a relevant approach to study the interaction between the hoof and the ground. Force plates are not adapted to compare different surfaces at high speed. A 3D dynamometric horseshoe (DHS), using 4 triaxial piezoelectric sensors, has been developed and validated. Objectives: To use the DHS to compare the effects of 2 track surfaces, an all-weather waxed track and a crushed sand track, on the GRF in trotter horses under training conditions. Methods: The right forelimb of 3 French Trotters was equipped with the DHS. Two tracks were tested in a straight line: a crushed sand track (S) and an all-weather waxed track (W). For each session, trials were repeated 3 times in a Latin square design. The speed of the runs was set at 10 m/s and recorded synchronously. For each trial, data acquisition was performed at 600 Hz and 10 consecutive strides were analysed. Statistical differences were tested using a general linear model procedure. Results: The amplitude of the maximal longitudinal braking force (Fx) was significantly lower on W compared to S. This event happened about 6% later in the stance phase on W. The magnitude of the GRF at impact decreased on W. The average speed and the mean stance phase duration were not statistically different on both surfaces. The stride length was about 6 cm longer on S. Conclusion and potential relevance: This study demonstrates the ability and sensitivity of the DHS to discriminate track surfaces by measuring the GRF at high speed. These preliminary results show that the loading rate, the amplitude of horizontal braking and shock at impact are attenuated on W, which suggests a reduction of stresses in the distal limb. [source] Quantification of surface EMG signals to monitor the effect of a Botox treatment in six healthy ponies and two horses with stringhalt: Preliminary studyEQUINE VETERINARY JOURNAL, Issue 3 2009I. D. Wijnberg Summary Reasons for performing the study: Therapeutic options for stringhalt in horses are limited, whereas medical experiences with botulinum toxin type A (Botox) have been positive. To evaluate its effectiveness in horses, surface electromyography (sEMG) signals before and after injection need to be quantified. Hypothesis: Treatment of healthy ponies and cases with Botox should reduce muscle activity in injected muscles and reduce spastic movements without adverse side effects. Methods: Unilaterally, the extensor digitorum longus, extensor digitorum lateralis and lateral vastus muscles of 6 healthy mature Shetland ponies and 2 talented Dutch Warmblood dressage horses with stringhalt were injected (maximum of 400 iu per pony and 700 iu per case; 100 iu in 5 ml NaCl divided into 5 injections) with Botox under needle EMG guidance. Surface EMG data were evaluated using customised software, and in the individuals gait was analysed using Proreflex. Statistical analysis was performed using mixed models and independent sample t test (P<0.05). Results: Surface EMG signals were quantified using customised software. The area under the curve (integrated EMG) in time was used as variable. It became significantly reduced in injected muscles after injection of Botox in normal ponies (P<0.05). This effect was present from Day 1 until Day 84 after injection. In the 2 cases, after injection of 3 muscles, the integrated EMG in time became significantly reduced in all 3 muscles. Kinematic measurements confirmed reduction of frequency and amplitude of hyperflexing or hyperabducting strides of the affected hindlimbs. The duration of effect was also seen in the cases until around 12 weeks after injection. Conclusions and potential relevance: After EMG guided injections of Botox, sEMG signals recorded from injected muscle were reduced, which proves this to be a useful tool in statistically evaluating a treatment effect. The positive results of this pilot study encourage further research with a larger group of clinical cases. [source] Preliminary study of mucosal IgA in the equine small intestine: specific IgA in cases of acute grass sickness and controlsEQUINE VETERINARY JOURNAL, Issue 5 2007F. G. NUNN Summary Reasons for performing study: There is much evidence to suggest that group III Clostridium botulinum (types C and D) are involved in the aetiology of equine grass sickness (EGS). Antibodies have been detected previously in the blood and high levels associated with resistance to disease. Specific mucosal antibodies in the gastrointestinal (GI) tract are likely to be important in protection, and this study was performed to ascertain if such antibodies could be detected and if their levels were related to disease state. Objectives: To develop a method for quantifying IgA antibodies to C. botulinum types C and D in the GI tract of horses and to relate antibody levels to disease status. Methods: Samples of tissue (n = 25: 6 duodenum, 7 jejunum and 12 ileum) were taken from acute grass sickness (AGS) cases and from control horses (n = 12; 4 samples from each site) at post mortem. They were extracted with the detergent saponin in the presence of protease inhibitors and assayed for total IgA, for specific IgA against botulinum neurotoxins types C and D (BoNT/C or BoNT/D), and against surface antigens of a BoNT/C negative strain of C. botulinum type C (SA) and of Clostridium tetani (TetSA), as a control. Specific IgA was expressed as percentage total IgA. Results: Compared to controls, significantly higher levels of specific IgA against BoNT/C were detected in the jejunum (P = 0.04) and ileum (P = 0.02) of AGS cases. Similarly, higher specific levels against BoNT/D were demonstrated in duodenum (P = 0.01) and jejunum (P = 0.02). Significantly higher levels of IgA against SA were demonstrated only in duodenal samples (P = 0.01). Conclusions: Levels of IgA antibody to BoNTs in control horses were at near undetectable levels, suggesting no recent exposure to toxins. In AGS cases, significantly higher levels of specific IgA were detected predominantly in jejunum and ileum. Potential relevance: If specific IgA is protective then any successful vaccine for EGS should induce a mucosal response. [source] Preliminary study of the crack healing and strength recovery of Al2O3 -matrix compositesFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 2 2004L. JUN ABSTRACT This study focused on the crack-healing behaviour of three commercial Al2O3,ceramic-matrix composites: TiCP/Al2O3, ZrO2/Al2O3 and SiCW/Al2O3. Vickers indentation was used to introduce surface flaws with different loads of 49, 98 and 196 N. Then the cracked specimens were annealed in air for 1 h at 1000, 1200 and 1400 °C. The annealing treatment was also conducted at 1200 °C in vacuum for 1 h. Results showed that the annealing treatments increased the indentation strength, but the extent of the increase was different. When annealed in air, the main crack-healing mechanism of TiCP/Al2O3 and SiCW/Al2O3 composites was chemical reaction. When annealed in vacuum, stress relaxation caused much less strength recovery. The main crack-healing mechanism of ZrO2/Al2O3 was the existence of low melting eutectic and the rearrangement of grains caused by ZrO2(m), ZrO2(t) transformation in the crack-opening process zone. The effects of annealing temperature, atmosphere and indentation load on the degree of strength recovery were all related to the crack-healing mechanisms. [source] Preliminary study of ciprofloxacin in active Crohn's diseaseINFLAMMATORY BOWEL DISEASES, Issue 1 2002Dr. George L. Arnold Abstract Based on limited reports of the successful use of antibiotics in the treatment of Crohn's disease (CD) and on the possibility that intestinal bacteria may be one of the etiologic factors playing a role in the pathogenesis of this condition, we undertook a study to evaluate the use of a broad-spectrum antibiotic in CD. Our team studied the efficacy of adding the antibiotic ciprofloxacin to the treatment of moderately active, but resistant cases of CD. Forty-seven adults with moderately active CD were randomly assigned treatment with ciprofloxacin 500 mg twice daily versus placebo twice daily for 6 months. The primary endpoint was the change in scores on the Crohn's Disease Activity Index (CDAI) from baseline to month 6. Although 47 patients were randomized, at 1 month of follow-up 28 patients received ciprofloxacin and 19 received placebo. The mean entry CDAI scores were not significantly different: 187 for the ciprofloxacin group versus 230 for the placebo group (p = 0.638). Mean CDAI scores at the completion of study were 112 for the ciprofloxacin group (n = 25) and 205 for the placebo group (n = 12), (p < 0.001). Disease remission is defined as a decrease in the CDAI score to less than 150 points. Our preliminary study suggests that ciprofloxacin may be an effective agent when added to the treatment of moderately active, resistant CD. [source] Study on the action of the active earth pressure by variational limit equilibrium methodINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 10 2010Li Xinggao Abstract Within the framework of limiting equilibrium approach, the problem of active earth pressure on rigid retaining wall is formulated in terms of the calculus of variations by means of Lagrange multipliers. It is transcribed as the functional of extreme-value problem by two undetermined function arguments, and is further transformed into determining the minimax solution of restrained functions incorporating the geometrical relations of the problem. The function of (fmincon) in the optimization toolbox of MATLAB 6.1 can be used to find the minimax solution. Computation results show there exist two kinds of modes of failure sliding along plane surface and rotating around log-spiral cylinder surface when the soil behind the walls reaches the critical active state. The magnitude of active earth pressure in the case of translational mode is less than that in the case of rotational mode. The location of action point of earth pressure in the case of translational mode is at or below height of the wall, and in the case of rotational mode, is above height of the wall. Preliminary study indicates a pair of numbers by two theoretical modes can be regarded as an interval estimation of active pressure. Copyright © 2009 John Wiley & Sons, Ltd. [source] Preliminary study of chemical bile duct embolization to treat hepatolithiasis in rabbitsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2006Fu Yu Li Abstract Background:, The high recurrence rate of hepatolithiasis is still a problem to be solved. The purpose of the present study was therefore to carry out a preliminary study of the practical value of chemical bile duct embolization (CBDE) to treat hepatolithiasis in rabbits. Methods:, Chemical bile duct embolization was performed with phenol or absolute ethanol along with N -butyl-cyanoacrylate. The feasibility and effectiveness of CBDE for chemical hepatectomy was assessed by investigating histological changes, biochemistry for hydroxyproline and in situ hybridization for collagen I. Results:, Histologically, the mucosal epithelia of the embolized bile ducts were entirely replaced by collagen fibers, thus effectively eradicating chronic proliferative cholangitis. Also of note, the diseased biliary duct lumens were completely filled with N -butyl-cyanoacrylate, thus effectively preventing calculus formation. The hepatocytes also disappeared completely in the periphery of the embolized lobe, demonstrating that the desired effects of chemical hepatectomy were achieved through CBDE. In a further comparison of embolizing agents, the phenol-cyanoacrylate embolized livers and bile ducts had a higher level of hydroxyproline and collagen I than those embolized with ethanol plus cyanoacrylate. Conclusion:, Chemical bile duct embolization is a promising approach to prevent the recurrence of hepatolithiasis and to achieve the effect of chemical hepatectomy. [source] Preliminary study on the monitoring of glutathione S-tranferase activity toward styrene oxide by electromigration methodsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 12 2005ková Abstract A new method has been developed for the monitoring of glutathione S-tranferase (GST) detoxification activity toward styrene oxide (SO). The enzymatic reaction was carried out directly in a thermostatted autosampler vial and the formation of conjugates between glutathione (GSH) and SO was monitored by sequential MEKC runs. The determinations were performed in a 50-,m fused silica capillary using 50 mM SDS in 20 mM phosphate 20 mM tetraborate buffer (pH 8.3) as a background electrolyte; separation voltage 28 kV (positive polarity), temperature of capillary 25°C, and detection at 200 nm. The method is rapid, amenable to automation, and requires only small amounts of samples, which is especially important in the case of GST isoenzyme analyses. [source] Preliminary study on the use of near-infrared reflectance spectroscopy to assess nitrogen content of undried wheat plantsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2007Alejandro Morón Abstract Near-infrared reflectance (NIR) spectroscopy combined with chemometrics was used to assess nitrogen (N) and dry matter content (DM) and chlorophyll in whole-wheat plant (Triticum aestivum L). Whole-wheat plant samples (n = 245) were analysed by reference method and by visible and NIR spectroscopy, in fresh (n = 182) and dry (n = 63) presentations, respectively. Calibration equations were developed using partial least squares (PLS) and validated using full cross-validation (leave-one-out method). Coefficient of determination in calibration (R2CAL) and the standard error of cross-validation (SECV) for N content in fresh sample presentation, after second derivative, were 0.89 (SECV: 0.64%), 0.86 (SECV: 0.66%) and 0.82 (SECV: 0.74%) using the visible + NIR, NIR and visible wavelength regions, respectively. Dry sample presentation gave better R2CAL and SECV for N compared with fresh presentation (R2CAL > 0.90, SECV < 0.20%) using visible + NIR. The results demonstrated that NIR is a suitable method to assess N concentration in wheat plant using fresh samples (unground and undried). Copyright © 2006 Society of Chemical Industry [source] Preliminary study of laser welding for aortic dissection in a porcine model using a diode laser with indocyanine greenLASERS IN SURGERY AND MEDICINE, Issue 5 2003Masanori Fujita MD Abstract Background and Objectives The objective of this study was to determine whether a dissected aorta could be welded by a diode laser with a solder using an in vitro porcine aortic dissection model. Study Design/Materials and Methods Porcine aortic strips were dissected into two flaps and the dissected faces were immersed in a solution of indocyanine green. The two flaps were pressed at 0.2 kg/cm2 with contact between the two immersed faces. The pressed flaps were irradiated with a diode laser (810 nm) at intensities of 170,425 W/cm2 for 8 seconds. The welded flaps were studied by light microscopy and the adhesive strengths were measured. Results The irradiated flaps were successfully welded. The breaking stress, the maximum stress recorded in a stress-strain curve, increased with increase in irradiation intensity up to 396 W/cm2 (2.7,×,102 mmHg) and decreased when the intensity reached 425 W/cm2. In the specimen irradiated at 396 W/cm2, the welded faces showed continuous fusion of elastin layers, while some voids were seen between the welded faces in the specimen irradiated at 425 W/cm2. Conclusions The dissected porcine aortas were successfully welded using a laser with solder. The results suggest that the welded aorta can bear physiological blood pressure. Lasers Surg. Med. 32:341,345, 2003. © 2003 Wiley-Liss, Inc. [source] Preliminary study on DNA damage in non breast-fed infantsPEDIATRICS INTERNATIONAL, Issue 2 2002en DÜndaröz Abstract Background: There are many advantages of human milk for infants, including protection against cancer development and the advantages have been emphasized in several studies. In this study, infants fed by human milk has been compared with those fed by cow's milk concerning DNA damage. Methods: The level of genetic damage in the peripheral blood lymphocytes of infants who were fed mainly by cow's milk and breast milk has been studied by sister chromatid exchange (SCE) analysis, which is a sensitive measurement of chromosomal damage. Each group consisted of 30 infants, whose ages ranged from 9 to 12 months. Results: A significant increase (P < 0.0001) was found in the frequencies of SCE of infants not breast-fed (n = 30, mean SCE/cell ± SD: 8.66 ± 1.15) compared to those who were breast-fed (n = 30, mean SCE/cell ± SD: 4.93 ± 0.82). Conclusion: To our knowledge, there has been no published study investigating SCE ratio regarding DNA damage in infants not breast-fed. Molecular mechanism of DNA damage caused by the absence of human milk protection is a subject of future investigations. [source] Preliminary study of the analysis of oligogalacturonic acids by electrospray ionization mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 12 2001Liang Zhu During systematic studies of the behavior of oligogalacturonic acids (OGAs) under different conditions using electrospray ionization mass spectrometry (ESI-MS), cation adduction, fragmentation and non-covalent binding were found to be the three major problems that compromised the analysis of OGAs by ESI-MS. By adjusting solution components, capillary temperature and capillary voltage in the ESI source, an optimized condition was found that gave a clean and clear spectrum of trigalacturonic acid. A direct injection ESI-MS technique based on the use of aqueous acetonitrile and acetic acid and triethylamine (TEA) as modifiers has been applied to analyze a mixture including mono-, di- and trigalacturonic acids, which will facilitate further applications of ESI-MS in the analysis of mixtures of OGAs. Copyright © 2001 John Wiley & Sons, Ltd. [source] Preliminary study of stress in undergraduate nursing students in SingaporeASIA-PACIFIC PSYCHIATRY, Issue 2 2009Chi Ching Lim BScN Abstract Introduction: Stress experienced by nursing students may adversely affect academic achievement, personal wellbeing and long-term professional capabilities. The current study is the first to report levels and sources of stress among Singaporean students undertaking a pre-registration baccalaureate nursing degree. Methods: An exploratory survey was conducted with students from all three year levels (n=112, 65% response rate) using the Stress in Nursing Students (SINS) scale. Use of this tool also enabled a regional comparison of results with published data from a nursing cohort in Hong Kong. Perceptions of support were measured using the Social Support Rating Scale (SSRS). It was hypothesized that students with higher levels of social support would report less stress. Results: In comparison to other year levels, Year 3 students reported higher levels of overall, clinical, and financial stress. There were statistical differences between Year 3 and Year 1 students in relation to clinical and financial stressors, but not with Year 2, nor were relationships found across year of study and confidence and education subscales. Level of stress was lower compared to Hong Kong nursing students. There were statistically significant differences on stress associated with clinical (P<0.01) and confidence (P<0.001) domains between datasets, but no differences on subscale scores for education and financial stressors. Social support was not statistically associated with stress. Discussion: Student stress increased throughout the program and was not mediated by social support. Awareness of types and progression of stress can inform professional development activities to bolster coping, and minimize adverse psychological, academic and professional consequences. [source] Preliminary study of D-dimer as a possible marker of acute bowel ischaemiaBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 3 2001Dr S. Acosta Background: Occlusion of the superior mesenteric artery (SMA) demands prompt recognition and diagnosis. No accurate diagnostic method is available. The aim of this study was to determine whether the fibrinolytic marker D-dimer is a useful early marker of acute bowel ischaemia. Methods: Fourteen patients suspected of having acute bowel ischaemia were analysed for an increase in plasma D-dimer level. Results: Six patients had embolic or thrombotic occlusion of the SMA and all had significantly higher D-dimer levels than those without thromboembolic occlusion (P < 0·05). Four patients with strangulation of the small bowel due to adhesions and one with a ruptured aortic aneurysm also had raised D-dimer values. Conclusion: In patients with suspected thromboembolic occlusive disease of the SMA, a raised level of D-dimer indicated the presence of acute bowel ischaemia, whatever the cause. A more extensive prospective study is needed to evaluate a potential survival benefit using the test as a marker of the need for urgent laparotomy. © 2001 British Journal of Surgery Society Ltd [source] Fitness to drive in glaucoma patients- Preliminary study resultsACTA OPHTHALMOLOGICA, Issue 2009AM STEVENS Purpose To develop a useful binocular 30° visual field criterion to predict safe driving behaviour in glaucoma patients by comparing perimetric data with an actual driving test on the road. Methods The sample will consist of 200 driving glaucoma patients, recruited in 2 university based glaucoma clinics (Ghent and Leuven, Belgium). Inclusion criteria are glaucomatous optic disc damage and/or glaucomatous field defects. Exclusion criteria are concomitant ocular disease, cataract > LOCS 2, systemic disease or medication affecting the visual field. Data collection will include demographic and medical data, driving habits, and Mini Mental Status. A complete ophthalmic examination wil be done including Goldmann, SAP and Esterman visual field testing. In addition, UFOV test, stereopsis and contrast sensitivity testing will be performed. All subjects will perform an on the road driving test with a driving expert of the Belgian Institute for Traffic Safety. Subjects can pass, fail, or pass the test with limitations. An attempt will be made to develop an algorithm of visual field abnormalities that predict as accurately as possible the outcome of the practical driving test. Results Preliminary results of the first 50 included patients will be presented. [source] Monitoring Lung Resistivity Changes in Congestive Heart Failure Patients Using the Bioimpedance TechniqueCONGESTIVE HEART FAILURE, Issue 6 2005Sharon Zlochiver MSc The feasibility of a novel, dedicated system for monitoring lung resistivity in congestive heart failure patients, implementing a hybrid approach of the bioimpedance technique, was assessed in this preliminary study. Thirty-three healthy volunteers and 34 congestive heart failure patients were measured with the PulmoTrace system (Cardiolnspect, Tel Aviv University, Tel Aviv, Israel) during tidal respiration, and the ability to monitor the respective lung resistivity values was assessed. Mean left and right lung resistivity values of 1205±163 and 1200±165 ,·cm for the control group and 888±193 and 943±187 ,·cm for the congestive heart failure group were found, indicating a significant (p<2·10,7) difference between the two groups. The results of long-term monitoring of two patients during medical treatment are also shown. This hybrid approach system is believed to improve diagnostic capabilities and help physicians to better adjust medication dosage on a frequent basis. [source] Variable-field relaxometry of iron-containing human tissues: a preliminary studyCONTRAST MEDIA & MOLECULAR IMAGING, Issue 4 2009Aline Hocq Abstract Excess iron is found in brain nuclei from neurodegenerative patients (with Parkinson's, Alzheimer's and Huntington's diseases) and also in the liver and spleen of cirrhosis, hemochromatosis and thalassaemia patients. Ferritin, the iron-storing protein of mammals, is known to darken T2 -weighted MR images. Understanding NMR tissue behavior may make it possible to detect those diseases, to follow their evolution and finally to establish a protocol for non-invasive measurement of an organ's iron content using MRI methods. In this preliminary work, the MR relaxation properties of embalmed iron-containing tissues were studied as well as their potential correlation with the iron content of these tissues. Relaxometric measurements (T1 and T2) of embalmed samples of brain nuclei (caudate nucleus, dentate nucleus, globus pallidus, putamen, red nucleus and substantia nigra), liver and spleen from six donors were made at different magnetic fields (0.00023,14 T). The influence of the inter-echo time on transverse relaxation was also studied. Moreover, iron content of tissues was determined by inductively coupled plasma atomic emission spectroscopy. In brain nuclei, 1/T2 increases quadratically with the field and depends on the inter-echo time in CPMG sequences at high fields, both features compatible with an outer sphere relaxation theory. In liver and spleen, 1/T2 increases linearly with the field and depends on the inter-echo time at all fields. In our study, a correlation between 1/T2 and iron concentration is observed. Explaining the relaxation mechanism for these tissues is likely to require a combination of several models. The value of 1/T2 at high field could be used to evaluate iron accumulation in vivo. In the future, confirmation of those features is expected to be achieved from measurements of fresh (not embalmed) human tissues. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||