30 research outputs found
The impact of exceptional loadcases on a heavy lift crane (PTC-140/200 DS)
The PTC-140/200 DS is the newest generation super heavy lift crane designed by Mammoet. This modular crane can be build in several different configurations and has a capacity of 3200 tonnes maximum. The PTC-140/200 DS is designed to meet both European and American safety standards. Both standards prescribe multiple safety factors to account for the various loads on the crane. However, the loads that occur during exceptional/accidental events, are hard to predict and are thus usually not accounted for by standards. The goal of this report is to provide more insight in the impact of exceptional loadcase on the structural integrity and overall stability of the PTC-140/200 DS. The following exceptional loadcases are investigated; 1. Sudden release of load 2. Breakage of a mainboom luffing wire rope 3. Breakage of a jib luffing wire rope 4. Breakage of a hoisting wire rope 5. Activation of the slewing emergency stop Each loadcase is investigated by means of a finite element model (FEM) that also accounts for the dynamic effects. The FEM model has been verified by the results of a second analytical calculation. The first loadcase investigates the impact of the sudden release of load. The sudden `removal' of load causes an impulse load that gives the boom enough energy to rebound. It has been found that the worst-case configuration does not tip over, because the boomstops stop the boom at 88.88_ (initial angle: 85_). Moreover, the stresses found in the structure are all below yield stress. It is however recommended to further investigate the uplifting forces after load release since the reaction forces at the front of the crane become negative in the first seconds. In the second loadcase, the impact of the breakage of a mainboom luffing wire rope is investigated. Half a second after breakage, the back left bogies start to come of the rail, which results in an increase of the hoist radius. This is aggravated by the swinging of the load and together, this leads to exceedance of the moment equilibrium between counterweight and load. Within six seconds after breakage, all rear bogies are lifted from the rail and ultimately, the crane tips forward. The third loadcase describes the breakage of a jib luffing wire rope. The jib luffing wire ropes transfer forces from the jib through the struts to the under carrier. Due to breakage, the struts are eccentrically loaded. The torsion in the masthead reducer section is 1.5 times the design limit and the upper and lower strut exceed this with a factor of 2.7 and 4.3 respectively. So the breakage of a jib luffing wire results in the plastic deformation of the struts and the masthead reducer section. Whether this leads to a total collapse of the struts, has to follow from an analysis of a detailed model that includes plastic material behavior. The fourth loadcase, breakage of a hoist wire rope, shows similarities with the breakage of a jib luffing wire, because both result in an eccentric loading of the construction. In this loadcase, the eccentric load directly applies to the masthead which gives a higher torsion in the masthead reducer section (two times higher than allowed). The torsion in the struts are below design limits. In the last loadcase, a slewing emergency stop is simulated by applying the brake deceleration to the constraint model. The brake capacity of the crane is sufficient to stop the crane within the specified maximum stopping time. However, it was also found that the back of the crane will come much earlier to a standstill than the front, which could lead to high bending stresses in the components that connect the front- and back base frames. This investigation showed that a sudden release of load and an emergency stop have no consequences for the structural integrity and stability of the PTC-140/200 DS. Breakage of a wire rope however does compromise the structural integrity of the crane. The breakage of a mainboom luffing wire even results in the fall over of the whole crane. Since the breakage of wire ropes have significant impact on the crane, it is recommended to pay special attention to the inspection procedure of the wire ropes. Further more, it is recommended to consider alternative jib/mainboom luffing systems that limit the eccentric loading in case of breakage.Mechanical, Maritime and Materials EngineeringMarine and Transport TechnologyTransport Engineering and Logistics2013.TEL.776
Comments on "Effects of uterine manipulation on surgical outcomes in laparoscopic management of endometrial cancer: a prospective randomized clinical trial"
Liver enzyme elevation induced by hyperemesis gravidarum: aetiology, diagnosis and treatment
Liver enzyme elevation induced by hyperemesis gravidarum: aetiology, diagnosis and treatment. Conchillo JM, Pijnenborg JM, Peeters P, Stockbrugger RW, Fevery J, Koek GH. Department of Internal Medicine, University Hospital Maastricht, PO Box 5800, 6202 AZ Maastricht, The Netherlands. Three primigravidae were admitted during the first trimester of pregnancy with nausea, vomiting, ketonuria and liver enzyme elevation of varying severity. A 29-year-old woman had elevated aminotransferase values, at levels described in the literature (ASAT 112 U/l, ALAT 214 U/l). The second patient, a woman aged 26 years, had undergone in vitro fertilisation and showed higher liver enzyme elevation, including the total bilirubin level (ASAT 250 U/l, ALAT 474 U/l, total bilirubin 59.8 micromol/l). A 30-year-old woman had extremely high aminotransferase values (ASAT 705 U/l, ALAT 1674 U/l) and she is the first reported patient with ALAT values exceeding 1,000 U/l in connection with hyperemesis gravidarum. Gallstone disease, viral and drug-induced hepatitis were excluded in all of these patients. Treatment was symptomatic and the abnormal liver tests returned to normal promptly when the vomiting resolved, independent of the severity of liver enzyme elevation. The pregnancies proceeded normally and all three patients delivered healthy babies
Health status and fatigue of postpartum anemic women:A prospective cohort study
Objective The incidence of postpartum anemia is high. Current therapy consists of iron supplementation or blood transfusions, based on the assumption that these treatments improve health status (HS) and reduce fatigue. The aim of this study was to compare HS and fatigue in postpartum women with and without anemia. Study design This prospective cohort study was performed in The Netherlands between April 2008 and August 2010 and involved 112 anemic (hemoglobin [Hb] < 10.5 g/dL) and 108 non-anemic (Hb ≥ 10.5 g/dL) women. The anemic women received oral iron supplementation. Within 48 h and 5 weeks after delivery, HS was measured using the 36 item Short-Form Health Survey (SF-36) and fatigue was measured using the Checklist Individual Strength (CIS). ANOVA for repeated measures was used to compare HS and fatigue scores among groups and across time. Results After adjustment for confounding variables, there were no differences in any of the HS and fatigue scores. HS and fatigue seem to be more influenced by a complicated delivery than by anemia. HS and fatigue scores significantly improved over time in all women. Conclusion HS and fatigue were not different among women with and without postpartum anemia.Keywords: Health status, Fatigue, Anemia, Iron deficiency, Postpartu
A randomized controlled trial examining the addition of folic acid to iron supplementation in the treatment of postpartum anemia
Objective To evaluate the efficacy of adding folic acid to oral iron supplementation in postpartum women with anemia. Methods A randomized controlled trial was conducted in the Netherlands between April 8, 2008, and August 31, 2010. A total of 112 postpartum women with anemia (hemoglobin < 10.5 g/dL) were randomly allocated to receive 600 mg/day ferrous fumarate plus 1 mg/day folic acid (FFFA group) or 600/day ferrous fumarate alone (FF group) for 4 weeks. Primary outcome measures were hemoglobin and health status. Secondary outcome measures were fatigue, compliance, and adverse reactions. Results No between-group differences were observed in hemoglobin and health status after treatment, and no differences were found in fatigue scores. Approximately 75% of all women reported having at least one symptom resulting from ferrous fumarate use. Constipation caused by ferrous fumarate was significantly associated with non-compliance (P = 0.014). Conclusion The addition of folic acid to iron supplementation is not beneficial in women with postpartum anemia, as it has no effect on hematologic or health status parameters
An added value for the hemoglobin content in reticulocytes (CHr) and the mean corpuscular volume (MCV) in the diagnosis of iron deficiency in postpartum anemic women
Item does not contain fulltextINTRODUCTION: To evaluate the use of reticulocyte hemoglobin content (CHr) and mean corpuscular volume (MCV) to identify truly iron-deficient women with postpartum anemia (PPA), in order to reduce unnecessary iron supplementation. METHODS: Three hundred women with more than 500 mL of blood loss or clinical signs of anemia were divided in a control (Hb >/= 10.5 g/dL, N = 150) and postpartum anemia group (PPA, Hb < 10.5 g/dL; N = 150). PPA women were given ferrous fumarate for a period of 4 weeks. Efficacy of the treatment was evaluated by comparing Hb, CHr, and MCV at baseline (T(0)) and after 4 weeks (T(4)). Using standard iron deficiency cut off values for MCV (80 fL) and CHr (28 pg) at T(0), we divided the PPA group of both parameters into two subgroups, one suggestive for iron deficiency and one suggestive for noniron deficiency. RESULTS: Irrespective of the parameter or the subdivision, delta Hb concentrations (T(4) -T(0)) showed a similar increase in all PPA subgroups investigated. Both parameters in the PPA subgroups below their respective cut off value showed a significant improvement toward normalization, while the MCV and CHr in the PPA subgroups above their respective cut off value did not show any significant increase. CONCLUSION: Our data suggest that the etiology of the anemia in postpartum anemic women is not always iron deficiency. Using a combination of Hb, MCV and CHr, we increased the stringency to identify truly iron-deficient postpartum anemic women, thereby reducing unnecessary iron supplementation in those women with sufficient iron stores
Letter-to-the-Editor “Laparoscopic treatment of early-stage endometrial cancer with and without uterine manipulator: Our experience and review of literature” by Tinelli R et al. (Surgical Oncology 25 (2016) 98–103)
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Vulvar mucinous adenocarcinoma with neuroendocrine differentiation: A case report and review of the literature
BACKGROUND: There are limited cases in literature of patients with mucinous adenocarcinoma of the vulva with neuroendocrine differentiation have. With this new case, we aim to provide an overview of the existing literature and present a tool with relevant markers for the pathologist in the differential diagnosis. CASE DESCRIPTION: A 92-year-old multiparous, Caucasian woman presented with a 8cm spherical tumor of the left major labium. Since the initial punch biopsy was not conclusive, a local resection was performed. Histopathological examination showed mucus production, large pools of mucin with trabeculae and cribriform glandular structures with strongly atypical columnar epithelium. Additional immunohistochemical analysis demonstrated expression of: CEA, CK7, EMA, and the neuroendocrine markers synaptophysin and chromogranin supporting the diagnosis. CONCLUSION: In this report, we present a new case of a mucinous adenocarcinoma of the vulva with neuroendocrine differentiation based immunohistochemical analysis. Due to the indolent tumor behavior, partial vulvectomy is the therapy of choice
Self-stigma and cognitive insight in individuals at ultra-high risk for psychosis
Background: Impaired cognitive insight and increased self-stigma have been consistently reported in individuals diagnosed with schizophrenia spectrum disorders, but little is known about its presence in individuals at ultra-high risk of developing a psychosis, although self-stigma is associated with transition.to psychosis. The current study examined whether self-stigma is already present in individuals at ultra-high risk of psychosis, and whether this is associated with impaired cognitive insight. Methods: 184 participants were recruited divided over three groups, namely individuals diagnosed with a schizophrenia spectrum disorder (SSD; n = 92, 34% females), individuals at ultra-high risk for psychosis (UHR; n = 43, 59% females) and general population controls (GPC; n = 49, 27% females). All participants completed assessments on demographic information (gender, age, education), and cognitive insight. In addition, participants with SSD and individuals at UHR completed a questionnaire on self-stigma. Results: The level of self-stigma did not differ between individuals at UHR and individuals diagnosed with SSD. Cognitive insight also did not differ significantly between the three groups, but the subscale self-reflection differed between the three groups [F(2,184) = 4.20, p = 0.02], with the UHR and SSD groups showing more self-reflection. Pearson’s correlation analyses showed that in individuals at UHR total cognitive insight and its self-reflection subscale were significantly associated with the alienation subscale of self-stigma, and in individuals with SSD self-certainty subscale of cognitive insight was significantly associated with stereotype endorsement. Conclusion: Findings show that self-stigma was already present in the UHR phase, to a similar degree as in individuals with a diagnosis of a SSD, and is thus not dependent of previous experience of having a label of SSD. Cognitive insight in individuals at UHR of psychosis appears to be intact, but individuals at UHR showed more self-reflectiveness, and individuals at risk with high cognitive insight also experience high levels of self-stigma. Overall findings from our study suggest that pre-emptive interventions targeting self-stigma, while considering cognitive insight, are needed early on in manifestation of psychotic illness, preferably already in the UHR phase.</p
Chemotherapy-induced peripheral neuropathy and its impact on health-related quality of life among ovarian cancer survivors:Results from the population-based PROFILES registry
Objective This study assessed the prevalence and risk factors of chemotherapy-induced peripheral neuropathy, and its impact on health-related quality of life among ovarian cancer survivors, 2–12 years after diagnosis. Methods Women (n = 348) diagnosed with ovarian cancer between 2000 and 2010, as registered by the Dutch population-based Eindhoven Cancer Registry, were eligible for participation. A questionnaire, including the EORTC QLQ-C30 and EORTC QLQ-OV28 measures, containing 3 items about neuropathy, was returned by 191 women (55%). Recurrence and chemotherapy data were obtained from medical records. Results Of all 191 women, the 129 women who received chemotherapy more often reported having tingling hands/feet and feeling numbness in fingers/toes, specifically 51% reported “a little” to “very much” of these symptoms vs. about 27% who did not receive chemotherapy. Women reporting more neuropathy symptoms reported lower levels of functioning and overall quality of life. They also reported more symptoms of fatigue, nausea/vomiting, pain, dyspnea, insomnia, appetite loss, and financial problems. Moreover, women reporting more neuropathy symptoms had experienced the disease and treatment more often as being a burden and were more worried about their health, had more gastrointestinal and hormonal symptoms, hair loss and more other chemotherapy side effects. Linear regression analyses showed that more cycles of chemotherapy, more recurrences and a shorter period since last treatment were associated with a higher neuropathy score. Conclusion Neuropathy symptoms were experienced by 51% of women with ovarian cancer who received chemotherapy even up to 12 years after the end of treatment, and this seriously affected their HRQoL. Keywords: Cancer, Oncology, Ovarian cancer, Chemotherapy, Neuropathy, Neurotoxicity Health-related quality of life Chemotherapy-induced peripheral neuropath