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Experimental determination of both steady-state and dynamic performance of a journal bearing requires the use of a high precision spindle with a vanishingly small range of run-out. This was achieved by first eliminating the mechanical run-out of the spindle by grinding the journal specimen while rotating in place. Once the mechanical run-out was removed, the electrical run-out sensed by the displacement proximity-probe-transducers was also removed. Using this procedure the mechanical and electrical run-outs of a research spindle were reduced to less than 0.2 micron (10 [micro]in.), which is better than the resolution of the data acquisition system, 1 micron (50 [micro]in.).

Methods for inspecting coating mechanical properties and adhesion on final products, considering quantitative criteria are of high importance. In this paper, relevant characteristic examples for determining the adhesion of a MoN and a TiC PVD coating deposited on steel substrate are introduced. The mechanical properties of the coatings and their steel substrates were determined via nano-indentations and a FEM supported evaluation of the obtained results. The coatings' adhesion and fatigue were quantified by inclined and perpendicular impact tests respectively, coupled with appropriate finite elements method (FEM) calculations. The inclined impact tests were conducted under lubricated conditions for avoiding abrasion caused by sliding friction on the coated surfaces. In this way, the coating fatigue failure during this test was mainly affected by the impact load, the film adhesion and the material's properties. Based on these results, the coating adhesion was estimated considering the impact loads and the determined material properties. [ABSTRACT FROM AUTHOR]

The novel angular-compliant composite bearing design, in which a hydrodynamic sleeve is put inside a ball bearing, will result in improved dynamic and thermal characteristics. However, the primary application of this type of bearing still needs to be determined. In addition, this new design concept still faces numerous challenges which can only be dealt with through further evaluations and testing. These include its applicability in real life situations, potential performance problems arising from its design, problems due to the proposed axial lubrication scheme and its lubrication requirements.

Squeeze film dampers (SFD) have been used for many years to control the vibrations of the shafts in high-speed rotating machinery. Dual squeeze film dampers are essentially a combination of two SFDs separated by a sleeve. Normal operation utilizes only one oil film, as in a conventional damper, and the sleeve is fixed in place. However, under high load conditions, the sleeve is released and both oil films become operational. An experimental facility was designed and built to study both single and dual SFD behavior within mechanically controlled orbits. The first part of this paper presents a description of this test rig and provides a dynamic model of a single SFD. In this portion of the paper, we present results obtained while the inner sleeve is released and both oil films are operational. Here the inner sleeve is not supported by any mechanical device; the anti-rotational effect is provided by the opposed actions of the inner oil film and of the outer oil film. The modeling covers the inner and the outer oil films, the elastic fixtures, the unbalanced shaft, and the sleeve. Numerical results are compared with the experimental data. [ABSTRACT FROM AUTHOR]

Describes a dual clearance squeeze film damper (SFD) test rig and a dynamic model of a single SFD. Purpose of dual SFD; Bearing characteristics and lubricant properties; Dynamics of the shaft.

Cutaneous squamous scell carcinoma (cSCC) is a frequent non-melanoma skin cancer that originates from keratinocytes with increased prevalence. cSCC can be either in situ, as in Bowen's disease, or extended. Advanced age, accumulated sun exposure, light pigmentation, and prior skin cancer diagnosis are all significant risk factors for cSCC. Although most cSCCs can be treated surgically, some recur and metastasize, resulting in death. The role of immune status is not yet determined in the prognosis of these patients. Objective . Immunosuppressed patients are more likely to develop cSCC, which is often characterized by more aggressive, multifocal lesions. This study aimed to determine the risks of mortality in patients with cSCC and immunosuppression versus non immunosuppression and to compare variations in overall survival based on different clinical features. Method . We evaluated clinical cases of patients at "Sfantul Apostol Andrei" Emergency Hospital of Galati, Romania, from 1 March 2018 to 1 April 2024. Subjects in the trial had to be at least 18 years old and have a pathologically confirmed diagnosis of cutaneous head and neck squamous cell carcinoma (cHNSCC). We divided the patients into two different categories based on whether they had immunosuppression. Results. In this cohort of 68 subjects with cSCC, patients with immunosuppression had significantly lower overall survival, as well as lower three- and five-year survival rates compared with those without immunosuppression, even after adjustment for age, sex, stage, and previous surgical treatment. The median survival time for immunosuppressed individuals ranged from 11 to 21 months, varying based on their particular characteristics, and most critically, on the presence of other malignancies, while that of immunocompetent patients ranged from 18 to 51 months. In addition, immune-deficient patients with early-stage disease had a 21-month median survival rate that changed to11 months for advanced-stage cases. In a similar manner, immunocompetent patients with early-stage cancer had a significantly better median survival than those withadvancedstages,43 versus 18months. Our results indicate that immunosuppression is a distinct risk factors associated with a less favorable outcome in patients with cHNSCC.

Background: medical teams continue to face challenges with infections following hip replacement surgery, whether they occur shortly after the procedure or months or years later. Certain medical conditions like diabetes, rheumatoid arthritis, and obesity are risk factors that make patients more susceptible to infections. Traditional intervention methods such as DAIR, one-step, or two-step procedures are being enhanced and refined to ensure quicker and more effective treatment. Some cases present particularly difficult challenges, featuring persistent fistulas and unpredictable responses to treatment., Methods: in our article, we share two unique cases, detailing their histories, progressions, and treatment decisions. We explore the use of antibiotic-impregnated calcium biocomposite as a local adjuvant therapy and the application of negative pressure therapy to expedite healing. The system of NWPT has seen widespread uptake and is now implemented routinely for open wounds, such as open fractures, fasciotomies, ulcers, and infected wounds., Results: our findings demonstrate that surgical debridement and calcium sulfate bead insertion successfully treat bone and joint infections without causing any side effects or complications. As a particularity, in the first case, we encountered the exteriorization of Stimulan pearls after surgery, without other complications related to the biocomposite., Conclusions: we have found that NPWT is a beneficial tool in managing complex wounds in both acute and chronic stages, after the infection is cured, reducing the need for frequent dressing changes, shortening hospital stays, and enhancing patient comfort.

Background: Given the increasing rate of infections following hip arthroplasty, one of the current options is the application of a biocomposite at the site of the infection. One of the products used is Stimulan, a completely resorbable calcium sulfate, designed to treat acute and chronic infections. This biocomposite has a controlled purity, is easy to mix with liquid, powder, and antibiotics, and can be applied directly to the site of infection, or it can be injected. Methods: We analyzed data from 76 patients, who were admitted to the County Clinical Hospital of Emergency "St. Apostol Andrei" in Galati during January 2017-September 2023, with a diagnosis of infection associated with hip arthroplasty. Results: In 69.73% of cases (52 patients), we decided to keep the implant in place. In this subgroup, Stimulan was applied in 26 cases (57.78%). Of these, 100% were cured-compared to the subgroup in which Stimulan was not applied, where this percentage was lower. All patients underwent chemical and mechanical toileting, and for 24 patients (20.27%), it was necessary to ablate the implant with or without the application of Stimulan, then reimplantation of the prosthesis. Conclusions: The patients with Stimulan had a longer average length of hospitalization, almost half of them required intervention in two periods, and a quarter required the implantation of spacers. However, the cure rate was higher, only in three people could we not control the infection, and there was no death. This study confirms the effectiveness of the treatment when using a biocomposite in addition to the classical treatment for both acute and chronic cases.

Background: Ideas about Artificial intelligence appeared about half a century ago, but only now is it becoming an essential element of everyday life. The data provided are becoming a bigger pool and we need artificial intelligence that will help us with its superhuman powers. Its interaction with medicine is improving more and more, with medicine being a domain that continues to be perfected. Materials and Methods: The most important databases were used to perform this detailed search that addresses artificial intelligence in the medical and surgical fields. Discussion: Machine learning, deep learning, neural networks and computer vision are some of the mechanisms that are becoming a trend in healthcare worldwide. Developed countries such as Japan, France and Germany have already implemented artificial intelligence in their medical systems. The help it gives is in medical diagnosis, patient monitoring, personalized therapy and workflow optimization. Artificial intelligence will help surgeons to perfect their skills, to standardize techniques and to choose the best surgical techniques. Conclusions: The goal is to predict complications, reduce diagnostic times, diagnose complex pathologies, guide surgeons intraoperatively and reduce medical errors. We are at the beginning of this, and the potential is enormous, but we must not forget the impediments that may appear and slow down its implementation.

Acute peritonitis accounts for 1% of inpatient surgical emergencies and is the second leading cause of sepsis in patients in intensive care departments. Diagnosis through laboratory analysis in bacterial peritonitis focuses mainly on the biomarkers, procalcitonin and C-reactive protein. A 73-year-old male patient presented with meteorism, diarrhea, vomiting, fever, and hypotension. Laboratory investigations showed very high procalcitonin and C-reactive protein values, and abdominal radiography revealed paraumbilical hydroaerial levels, which suggested septic shock of intra-abdominal origin. Emergency laparotomy was performed, which revealed agglutinated intestinal loops in the right iliac fossa with false membranes, purulent fluid, overdistended jejunum and ileum with an occlusive appearance, acute gangrenous appendicitis with perforation, and suppurative omentitis. The intraoperative diagnosis was acute neglected peritonitis in the occlusive phase owing to acute gangrenous appendicitis with perforation and suppurative omentitis. Laboratory analysis in conjunction with imaging provides important information in the early diagnosis of infectious pathology in elderly patients, even if these methods do not accurately identify the cause. The combination of procalcitonin and C-reactive protein biomarker levels successfully contributed to the diagnosis in this case. Notably, the patient's white blood cell counts were inconsistent with the severity of the infection.