Retaining Mechanical Properties of GMA-Welded Joints of 9%Ni Steel Using Experimentally Produced Matching Ferritic Filler Metal

Motivated by the loss of tensile strength in 9%Ni steel arc-welded joints performed using commercially available Ni-based austenitic filler metals, the viability of retaining tensile strength using an experimentally produced matching ferritic filler metal was confirmed. Compared to the austenitic Ni-based filler metal (685 MPa), higher tensile strength in gas metal arc (GMA) welded joints was achieved using a ferritic filler metal (749 MPa) due to its microstructure being similar to the base metal (645 MPa). The microstructure of hard martensite resulted in an impact energy of 71 J (−196 °C), which was two times higher than the specified minimum value of ≥34 J. The tensile and impact strength of the welded joint is affected not only by its microstructure, but also by the degree of its mechanical mismatch depending on the type of filler metal. Welds with a harder microstructure and less mechanical mismatch are important for achieving an adequate combination of tensile strength and notched impact strength. This is achievable with the cost-effective ferritic filler metal. A more desirable combination of mechanical properties is guaranteed by applying low preheating temperature (200 °C), which is a more practicable and economical solution compared to the high post-weld heat treatment (PWHT) temperature (580 °C) suggested by other research.     

Early Diagnosis of Colonic Anastomotic Leak With Peritoneal Endoscopy

Background and Objectives:

At present, we do not have a reliable method for the early diagnosis of colorectal anastomotic leakage (AL). We tested peritoneal flexible endoscopy through a port placed in the abdominal wall in the early postoperative course, as a new diagnostic method for detection of this complication and evaluated the suggested method for safety, feasibility, and accuracy.

Methods:

Ten swine were randomized into 2 groups: group A, colorectal anastomosis without leakage; and group B, colorectal anastomosis with leakage. A button gastrostomy feeding tube was inserted percutaneously into the peritoneal cavity. Colorectal anastomosis (with or without defect) was created 48 hours after the first operation. The swine were examined by peritoneal flexible endoscopy 8 and 24 hours after the colonic operation, by a consultant surgeon who was blinded to both the presence and the allocated location of the of the anastomotic defect.

Results:

None of the animals showed signs of illness 48 hours after the intraperitoneal gastrostomy tube placement. More than half of the anastomosis circumference was identified in 60 and 10% of the animals at endoscopy 8 and 24 hours, respectively, after the anastomosis was created. Excessive adhesion formation was observed in all animals, irrespective of AL. The sensitivity and specificity of endoscopy in detecting peritonitis 24 hours after AL were both 60%.

Conclusions:

Peritoneal endoscopy is a safe and simple procedure. Visualization of the peritoneal cavity in the early postoperative course was limited due to adhesion formation. Further studies are needed to clarify the accuracy of the procedure and to address additional methodological concerns.     

Some remarks to the kinetics of anionic polymerization of ethylene oxide in dimethyl sulfoxide

The kinetics of ethylene oxide (EO) polymerization in dimethyl sulfoxide with potassium tert-butoxide as initiator at 323, 333, and 343 K has been studied. The process follows the first order with respect to initiator in the concentration range 1,5–5,9 · 10^?3 mol · dm^?3 and the rates are the same as in the polymerization of EO with dimsylpotassium (potassium methylsulfinylmethanide). It is supposed that the tert-butoxide and dimsyl anions are equally effective as initiators and their ionization equilibrium does not affect the polymerization rate. The above conclusion agrees well with the very slow chain transfer to dimethyl sulfoxide in the anionic polymerization of EO.     

Total laparoscopic aortic surgery versus minimal access techniques: review of more than 600 patients

In the following paper we describe our experience with a large number of patients in which either a laparoscopic assisted procedure or a total laparoscopic operation was performed. From 1996 until 2005 a total number of 638 aortic patients were operated on using a total laparoscopic or a laparoscopic assisted approach. A total laparoscopic operation was accomplished in 236 cases. A laparoscopic assisted aortic operation was performed in 402 patients. In aneurysm patients a tube graft was more frequently implanted. Thirty-day mortality was significantly higher in patients with a total laparoscopic abdominal aortic aneurysm repair (3.0%) compared to a laparoscopic assisted procedure (1.8%). There was no significant difference in mortality in patients with occlusive disease and a total laparoscopic aortofemoral bypass versus a laparoscopically assisted operation. The same tendency could be observed when analyzing the incidence of major perioperative complications. Again we found no significant difference in patients with occlusive disease yet more severe complications directly related to the operation in patients with a total laparoscopic aneurysm repair. There was a significantly increased complication rate in total laparoscopic aortoiliac repair with a bifurcated prosthesis compared to a tube graft repair: a tendency we could not observe in aneurysm patients with a laparoscopic assisted operation. Our data also show that there is a lot of room for technical improvements such as stapling devices or special grafts to reduce total operating times as well as the period of aortic crossclamping. The routine use of a minilaparotomy can hardly be a solution considering the technical drawbacks such as impaired vision and long term complications like ventral hernias. Compared to open surgery the midterm results of laparoscopic aortic procedures are promising. The time has come to prove that good results can be obtained in more than a few specialized centers.     

Age-dependent effect of secretagogues during colonic maturation

Intestinal secretory response is altered during colonic development. The aim of this report was to study the developmental changes of the Ca(2+)- and cAMP-induced regulatory pathways with special attention to the direct and indirect effect of secretagogues on the colonic epithelium. We investigated the effect of bethanechol, 5-hydroxytryptamine (5-HT), and histamine on Cl(-) secretion and stimulation of intracellular Ca(2+) ([Ca(2+)](i)) and cAMP in the distal colon of suckling, weanling and adult rats. In the presence of tetrodotoxin, immature colon of suckling and weanling rats displayed higher potency (EC(50)) of 5-HT to stimulate Cl(-) secretion, whereas the potency of histamine was not changed during development. The potency of bethanechol was reduced during weaning and partially restored in adulthood. 5-HT increased cAMP level similarly in both neonatal and adult colonic crypts, but the adults had higher basal level of cAMP than suckling rats. Also the effect of bethanechol on [Ca(2+)](i) was independent of colonic maturation. The results suggest that colonic Cl(-) secretion displays developmental changes of regulation depending on the non-neural secretagogue-signalling pathway and that these developmental changes seem to be localized somewhere outside colonocytes.     

The outcome of 131I treatment in Graves' patients pretreated or not with methimazole

Despite extensive use of iodine-131 ((131)I) treatment for Graves' hyperthyroidism, the optimal regimen of pretreatment with antithyroid drugs is still a matter of discussion. Our aim was to evaluate the success of (131)I treatment in patients with Graves' disease without and with pretreatment with methimazole (MMI). In a prospective randomized study 156 patients with Graves' disease were treated with fixed activity of 550 MBq (131)I. First group of 59 patients received only (131)I. The second group of 50 patients received MMI which was stopped seven days before (131)I. The third group of 47 patients received MMI until (131)I application. Patients were followed clinically and biochemically 1, 3, 6 and 12 months after (131)I treatment. Absorbed dose of (131)I and thyroid volume were measured in each patient. Our result showed that (131)I treatment success after twelve months was equally effective in the first and second group (96.6% and 96%, respectively), while in the third group, success was significantly lower (63.8%). Accordingly, the absorbed dose of (131)I was significantly higher in the first and in second group (144±104 Gy and 164±107 Gy, respectively), and lower in the third group (105±58 Gy). Thyroid volume gradually decreased without any significant difference between the three groups. In conclusion, our study provides evidence that application of (131)I is equally effective in the nonpretreated with MMI group and in the group discontinuing MMI one week before (131)I treatment, and it is more effective in these two groups as compared to the group in which pretreatment with MMI was administered till the day of (131)I application.     

Influence of wire extension and type on splint rigidity – evaluation by a dynamic and a static measuring method

Abstract – Objectives: To evaluate the influence of wire dimension and wire length on the splint rigidity of wire‐composite splints in vitro. Materials and Methods: A custom‐made artificial model was used. The central incisors simulated ‘injured’ teeth with increased mobility, and the lateral incisors and canines served as ‘uninjured’ teeth with physiological mobility. To assess horizontal and vertical tooth mobility before and after splinting, the Periotest and Zwick methods were applied. Teeth 13–23 were splinted using wire‐composite splint 1 (WCS1; Dentaflex 0.45 mm) and wire‐composite splint 2 (WCS2; Strengtheners 0.8 × 1.8 mm). Splint length was varied by successively shortening the wire. The influence of wire dimension was tested using t‐test and Wilcoxon–Mann–Whitney test with the Bonferroni‐Holm procedure (α = 0.05). To test the influence of wire length, anova and Kruskal–Wallis tests as well as Tukey range and Wilcoxon test with Bonferroni‐Holm procedure were applied (α = 0.05). Results: Wire dimension significantly influenced splint rigidity (P < 0.05). The wire length significantly influenced the splint rigidity of WCS1 in the horizontal dimension and WCS2 in the horizontal and vertical dimensions (P < 0.05). Splint rigidity was significantly reduced when splinting only ‘injured’ teeth compared with splints including ‘uninjured’ adjacent teeth (P < 0.05). No differences were found between splints including one or two ‘uninjured’ teeth on each side (P > 0.05). Conclusion: WCS1 is flexible compared with the more rigid WCS2. The wire length influences the rigidity. To ensure adequate fixation and reduce the risk of enamel damage during splint removal, the splint should include only one ‘uninjured’ tooth bilaterally.     

Sonographic assessment of normal kidney dimensions in the first year of life—a study of 992 healthy infants

The omission of standards for renal length in infants younger than 1 year may result in a statistically significant increase in the frequency of “spurious” nephromegaly. Nonetheless, there are only a few reports specifically dealing with normal kidney dimensions in infants. Based on sonographic assessments performed on a sample of 992 healthy infants, between January 2002 and December 2004, this paper sets up standards for normal kidney dimensions in children aged 0–3 months, 3–6 months, 6–9 months, and 9–12 months and establishes correlations between kidney dimensions (length, width, and volume) and body length and weight. Linear as well as non-linear nomograms, with percentiles for all the kidney variables examined, based on body length, are provided. Also, statistically significant differences in mean values (P = 0.000) for all the observed neonatal kidney parameters, depending on gestational age at birth, are demonstrated. Principal advantages of our nomograms are that they are based on a large number of examined healthy infants and that kidney dimensions are related to body length. In addition, subjects are divided into four sub-annual age groups demonstrating gender-related differences in renal growth dynamics. Our linear nomograms are easier to use for routine clinical practice, but the percentile-based non-linear nomograms we present cover a much wider range of variations in normal infant kidney dimensions.     

Supplementation with Guanidinoacetic Acid in Women with Chronic Fatigue Syndrome

A variety of dietary interventions has been used in the management of chronic fatigue syndrome (CFS), yet no therapeutic modality has demonstrated conclusive positive results in terms of effectiveness. The main aim of this study was to evaluate the effects of orally administered guanidinoacetic acid (GAA) on multidimensional fatigue inventory (MFI), musculoskeletal soreness, health-related quality of life, exercise performance, screening laboratory studies, and the occurrence of adverse events in women with CFS. Twenty-one women (age 39.3 ± 8.8 years, weight 62.8 ± 8.5 kg, height 169.5 ± 5.8 cm) who fulfilled the 1994 Centers for Disease Control and Prevention criteria for CFS were randomized in a double-blind, cross-over design, from 1 September 2014 through 31 May 2015, to receive either GAA (2.4 grams per day) or placebo (cellulose) by oral administration for three months, with a two-month wash-out period. No effects of intervention were found for the primary efficacy outcome (MFI score for general fatigue), and musculoskeletal pain at rest and during activity. After three months of intervention, participants receiving GAA significantly increased muscular creatine levels compared with the placebo group (36.3% vs. 2.4%; p < 0.01). Furthermore, changes from baseline in muscular strength and aerobic power were significantly greater in the GAA group compared with placebo (p < 0.05). Results from this study indicated that supplemental GAA can positively affect creatine metabolism and work capacity in women with CFS, yet GAA had no effect on main clinical outcomes, such as general fatigue and musculoskeletal soreness.