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Squeeze film dampers (SFDs) provide vibration attenuation and structural isolation to aircraft gas turbine engines which must be able to tolerate larger imbalances while operating above one or more critical speeds. Rotor-bearing-SFD systems are regarded in theory as highly nonlinear, showing jump phenomena and even chaotic behavior for sufficiently large levels of rotor imbalance. Yet, few experimental results of practical value have verified the analytical predictions. A test rig for measurement of the dynamic forced response of a three-disk rotor (45 kg) supported on two cylindrical SFDs is described. The major objective is to provide a reliable data base to validate and enhance SFD design practice and to allow a direct comparison with analytical models. The open-ends SFD are supported by four-bar centering structures, each with a stiffness of 3.5 MN/m. Measured synchronous responses to 9000 rpm due to various imbalances show the rotor-SFD system to be well damped with amplification factors between 1.6 and 2.1 while traversing cylindrical and conical modes critical speeds. The rotor amplitudes of motion are found to be proportional to the imbalances for the first mode of vibration, and the damping coefficients extracted compare reasonably well to predictions based on the full-film, open-ends SFD. Tight lip (elastomeric) seals contribute greatly to the overall damping of the test rig. Measured dynamic pressures at the squeeze film lands are well above ambient values with no indication of lubricant dynamic cavitation as simple theoretical models dictate. The measurements show absence of nonlinear behavior of the rotor-SFD apparatus for the range of imbalances tested.

Presents a study which validated and enhanced squeeze film dampers' (SFD) design practice in aircraft gas turbine engines, while comparing analytical models. Indepth look at rotor-bearing-SFD systems; Function of squeeze film dampers; Methodology used to conduct the study; Results of the study.

Background: Postpartum hemorrhage (PPH) contributes significantly to maternal morbidity and mortality. The use of cell salvage has been implemented in operating rooms across the world, but only a limited number of institutions have protocols for use of cell salvage during vaginal hemorrhage at the time of vaginal delivery. Observations suggest that blood salvaged from vaginal delivery is comparable to blood salvaged during cesarean delivery. Using pre-validated protocols of cell salvage, we sought to assess the feasibility and potential benefit of implementing cell salvage in our Labor and Delivery unit in all patients at high risk of hemorrhage., Methods: This was a prospective pilot study conducted from April 2022 to December 2022 on the Labor and Delivery floor at Mount Sinai Hospital in New York City. A total of 50 participants were identified for cell salvage after vaginal delivery during the study period. The mean age of participants was 34.4 years (SD 5.5). We utilized a cell salvage technique at the time of vaginal delivery in patients at high risk of PPH. We employed simple descriptive statistics and examined sums and percentages (and means and standard deviations, where appropriate). A simple equation was used to determine the average cell salvaged volume in each delivery and describe potential values. The HEMAsavR™ device (Ecomed Solutions, Mundelein, IL, USA) was used as a standby system to be used at the time of the vaginal delivery., Results: Fifty participants were identified for the cell salvage protocol as described. Despite a diversity of clinical risk factors, the sample consisted of predominately non-Hispanic White patients. The mean quantitative blood loss of cell salvaged samples was 157.2 mL (SD 153.0). We identified that, on average, >33% of vaginally shed blood could be used for cell salvage and improve patient blood management., Conclusion: The implementation of cell salvage in our Labor and Delivery unit was feasible and easy to perform. We identified that a significant volume of blood would be available for cell salvage. Further studies should be done to evaluate the benefit of cell salvage to improve postpartum recovery., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Program for the Protection of Human Subjects at Icahn School of Medicine at Mount Sinai issued approval 21-00903. The study team was granted a waiver of informed consent and HIPAA authorization, and enrolled subjects provided verbal assent prior to and after seeing an informational graphic approved by the IRB. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Cabrera et al.)

The sexually abused adolescent girl is attempting to cope with a disturbing past, threatening present, and disrupted future. She may also be feeling cut off or different from her friends at a time when, developmentally, peer contact is vital. This paper describes a group therapy experience offered to six 13 and 14 year old abuse victims in order to help them feel better about themselves, improve their social skills and reconnect with others their own age. The group focused on the girl's present, everyday functioning and the effects the family disturbances and abuse have had on them. The male and female co-therapists attempted to create an atmosphere of trust and mutual aid; discussions centered on the relationships among group members and the connections the girls make with their important others, including family, friends, and social agencies. As the sessions progressed, four main themes of concern emerged; the girls shared feelings of violation, loss, anger and, finally, hope for their future. The paper illustrates these themes, delineates some of the girls' group experiences, and changes they underwent, and points out some organizational issues for the therapists in running this type of group.

The patient in end-stage renal failure, whose life depends on an artificial kidney machine, must make major emotional and physical adjustments. The author describes how in-hospital group treatment can help these patients cope with their new life situation.

A patient with bronchogenic carcinoma had an electrocardiogram that was initially thought to be consistent with myocardial infarction and possible left ventricular aneurysm. A heart scan with radioactive 201thallium showed an area of sharply diminished uptake ("cold spot"); however, subsequent thoracotomy showed that this was caused by local pericardial and myocardial infiltration by tumor. This suggests a role for radioactive 201thallium in the detection of cardiac metastatic tumors.