MARKETING FINANCIAL PRODUCTS WITHIN THE ACTIVITY OF INVESTMENT BANKS

A production system which produces a large number of items in many steps can be modelled as a continuous flow problem. The resulting hyperbolic partial differential equation (PDE) typically is nonlinear and nonlocal, modeling a factory whose cycle time depends nonlinearly on the work in progress. One of the few ways to influence the output of such a factory is by adjusting the start rate in a time dependent manner.We study two prototypical control problems for this case: i) demand tracking where we determine the start rate that generates an output rate which optimally tracks a given time dependent demand rate and ii) backlog tracking which optimally tracks the cumulative demand. The method is based on the formal adjoint method for constrained optimization, incorporating the hyperbolic PDE as a constraint of a nonlinear optimization problem. We show numerical results on optimal start rate profiles for steps in the demand rate and for periodically varying demand rates and discuss the influence of the nonlinearity of the cycle time on the limits of the reactivity of the production system. Differences between perishable and non-perishable demand (demand vs. backlog tracking) are highlighted

Alignment of standards and assessments as an accountability criterion

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Eleutherodactylus colostichos, a new frog species from the Pramo de los Conejos, in the Venezuelan Andes (Anura: Leptodactylidae)

http://deepblue.lib.umich.edu/bitstream/2027.42/57136/1/OP700.pd

Genetic and morphological studies of Trichosirocalus species introduced to North America, Australia and New Zealand for the biological control of thistles

Trichosirocalus horridus sensu lato has been used as a biological control agent of several invasive thistles (Carduus spp., Cirsium spp. and Onopordum spp.) since 1974. It has been recognized as a single species until 2002, when it was split into three species based on morphological characters: T. horridus, Trichosirocalus briesei and Trichosirocalus mortadelo, each purported to have different host plants. Because of this taxonomic change, uncertainty exists as to which species were released in various countries; furthermore, there appears to be some exceptions to the purported host plants of some of these species. To resolve these questions, we conducted an integrative taxonomic study of the T. horridus species complex using molecular genetic and morphological analyses of specimens from three continents. Both mitochondrial cytochrome c oxidase subunit I and nuclear elongation factor 1α markers clearly indicate that there are only two distinct species, T. horridus and T. briesei. Molecular evidence, morphological analysis and host plant associations support the synonymy of T. horridus (Panzer, 1801) and T. mortadelo Alonso-Zarazaga & Sánchez-Ruiz, 2002. We determine that T. horridus has been established in Canada, USA, New Zealand and Australia and that T. briesei is established in Australia. The former species was collected from Carduus, Cirsium and Onopordum spp. in the field, whereas the latter appears to be specific to Onopordum

Functionalized Enzyme-Responsive Biomaterials to Model Tissue Stiffening in vitro

The mechanical properties of the cellular microenvironment play a crucial role in modulating cell function, and many pathophysiological processes are accompanied by variations in extracellular matrix (ECM) stiffness. Lysyl oxidase (LOx) is one of the enzymes involved in several ECM-stiffening processes. Here, we engineered poly(ethylene glycol) (PEG)-based hydrogels with controlled mechanical properties in the range typical of soft tissues. These hydrogels were functionalized featuring free primary amines, which allows an additional chemical LOx-responsive behavior with increase in crosslinks and hydrogel elastic modulus, mimicking biological ECM-stiffening mechanisms. Hydrogels with elastic moduli in the range of 0.5–4 kPa were obtained after a first photopolymerization step. The increase in elastic modulus of the functionalized and enzyme-responsive hydrogels was also characterized after the second-step enzymatic reaction, recording an increase in hydrogel stiffness up to 0.5 kPa after incubation with LOx. Finally, hydrogel precursors containing HepG2 (bioinks) were used to form three-dimensional (3D) in vitro models to mimic hepatic tissue and test PEG-based hydrogel biocompatibility. Hepatic functional markers were measured up to 7 days of culture, suggesting further use of such 3D models to study cell mechanobiology and response to dynamic variation of hydrogels stiffness. The results show that the functionalized hydrogels presented in this work match the mechanical properties of soft tissues, allow dynamic variations of hydrogel stiffness, and can be used to mimic changes in the microenvironment properties of soft tissues typical of inflammation and pathological changes at early stages (e.g., fibrosis, cancer)

TEVAR and periscope graft technique to treatment of huge aneurysm of aortic isthmus: Case report

Introduction: Thoracic endovascular aortic repair (TEVAR) has revolutionized the treatment of thoracic aortic aneurysms. Innovative techniques as chimney and periscope grafts can improve the outcomes of procedure. Herein, we report a case in emergency of huge Thoracic aortic aneurism. Presentation of case: An 86-year-old male with hypertension, diabetes mellitus, was referred to our hospital for chest pain. CT-angiography showed a huge aneurysm of aortic isthmus with signs of rupture. The patient was considered unfit for open surgery and an endovascular approach was chosen. This patient underwent endovascular repair with TEVAR, using the periscope graft technique to preserve patency in left subclavian artery (LSA). Discussion: Symptomatic ischemia from LSA coverage has been reported to occur in only a modest 6–10% of patients and is often sacrificed with impunity given coverage rates between 10 and 50%. In this case reported the lack of revascularization of LSA increased the risk of neurological manifestations or stroke. Periscope technique is feasible and safe to maintain perfusion to the subclavian artery, with a 93% primary patency at 2 years. Conclusions: Our experience using TEVAR with periscope graft technique as solution to address thoracic aneurysm of aortic isthmus was feasible and safe

Staged acute mesenteric and peripheral ischemia treatment in COVID-19 patient: Case report

Introduction: COVID-19 is an infectious disease that has been associated not only with respiratory complications. The COVID-19 disease includes, also damage to other organ systems as well as coagulopathy. The present report describes a case of COVID-19 presenting with acute mesenteric ischemia (AMI) and subsequent acute limb ischemia (ALI). Presentation of case: An 84-years old hospitalized female patient presenting diabetes and recent COVID-19 reported acute onset of abdominal pain and typical findings of AMI. The CT-angiography confirmed the AMI secondary to a superior mesenteric artery (SMA) occlusion. The patient was managed through an endovascular approach using a SMA mechanical thrombectomy and stenting with a good result. Discussion: Treatment of this life-threatening condition includes surgical resection of the necrotic bowel, restoration of blood flow to the ischemic intestine and supportive measure - gastrointestinal decompression, fluid resuscitation, hemodynamic support. Endovascular management of AMI is preferred over the standard surgical approach due to a reduced mortality and morbidity rates. Imaging findings of intestinal necrosis, however, represent an indication for AMI surgical treatment with explorative laparotomy. Different endovascular solutions have been employed to address AMI including mechanical thrombectomy, local thrombolysis, and PTA-stenting. Conclusion: COVID-19 clinical presentation can be atypical, including gastrointestinal symptoms. If a first embolic event occurs, an aggressive anticoagulation treatment could be inefficient to reduce the risk of subsequent embolization events. The limited life expectancy of such revascularization procedures should orientate towards less invasive treatments

Prediction of age at menopause from assessment of ovarian reserve may be improved by using body mass index and smoking status.

OBJECTIVE: Menopause is the consequence of exhaustion of the ovarian follicular pool. AMH, an indirect hormonal marker of ovarian reserve, has been recently proposed as a predictor for age at menopause. Since BMI and smoking status are relevant independent factors associated with age at menopause we evaluated whether a model including all three of these variables could improve AMH-based prediction of age at menopause. METHODS: In the present cohort study, participants were 375 eumenorrheic women aged 19-44 years and a sample of 2,635 Italian menopausal women. AMH values were obtained from the eumenorrheic women. RESULTS: Regression analysis of the AMH data showed that a quadratic function of age provided a good description of these data plotted on a logarithmic scale, with a distribution of residual deviates that was not normal but showed significant left-skewness. Under the hypothesis that menopause can be predicted by AMH dropping below a critical threshold, a model predicting menopausal age was constructed from the AMH regression model and applied to the data on menopause. With the AMH threshold dependent on the covariates BMI and smoking status, the effects of these covariates were shown to be highly significant. CONCLUSIONS: In the present study we confirmed the good level of conformity between the distributions of observed and AMH-predicted ages at menopause, and showed that using BMI and smoking status as additional variables improves AMH-based prediction of age at menopause