1,174 research outputs found
Facility layout problem: Bibliometric and benchmarking analysis
Facility layout problem is related to the location of departments in a facility area, with the aim of determining the most effective configuration. Researches based on different approaches have been published in the last six decades and, to prove the effectiveness of the results obtained, several instances have been developed. This paper presents a general overview on the extant literature on facility layout problems in order to identify the main research trends and propose future research questions. Firstly, in order to give the reader an overview of the literature, a bibliometric analysis is presented. Then, a clusterization of the papers referred to the main instances reported in literature was carried out in order to create a database that can be a useful tool in the benchmarking procedure for researchers that would approach this kind of problems
Non-invasive assessment of pulmonary vascular resistance in pulmonary hypertension: Current knowledge and future direction
Pulmonary Hypertension (PHT) is relatively common, dangerous and under-recognised. Pulmonary hypertension is not a diagnosis in itself; it is caused by a number of differing diseases each with different treatments and prognoses. Therefore, timely and accurate recognition of the underlying cause for PHT is essential for appropriate management. This is especially true for patients with Pulmonary Arterial Hypertension (PAH) in the current era of disease-specific drug therapy.
Measurement of Pulmonary Vascular Resistance (PVR) helps separate pre-capillary from post-capillary PHT, and is measured with right heart catheterisation (RHC). Echocardiography has been used to derive a number of non-invasive surrogates for PVR, with varying accuracy. Ultimately, the goal of non-invasive assessment of PVR is to separate PHT due to left heart disease from PHT due to increased PVR, to help streamline investigation and subsequent treatment.
In this review, we summarise the physiology and pathophysiology of pulmonary blood flow, the various causes of pulmonary hypertension, and non-invasive surrogates for PVR
Solving YCS : final report 2014/049
Yellow canopy syndrome (YCS) is a sporadic condition presenting as golden-yellowing of the mid canopy in sugarcane during the peak growing period of December to March. The key driver of YCS is growth rate and symptoms usually exhibit after rainfall. YCS can be induced or mitigated by altering sink strength and sugarcane can recover from a YCS event. Abiotic or biotic stress has a serious effect on the photosystems and the physiological fitness of the crop. There is a strong correlation between YCS expression, leaf sucrose and sink strength, independent of crop age. YCS symptomatic leaves always have high leaf sucrose and ?-glucan content. Under experimental conditions the pyrethroid bifenthrin supresses insect stress, promotes increased sink growth and maintains low leaf sucrose and ?-glucan levels. Induced senescence causes YCS plants to have a lower number of attached leaves. Yield loss precedes YCS expression and there is no correlation between YCS severity and cane yield or CCS. Lamina starch staining is a useful tool to assist in YCS identification. There is no strong evidence of genetic predisposition for YCS susceptibility. Industry-wide incidence and severity of YCS is too difficult to accurately assess due to its episodic nature, no single causal agent and the link to climate change and severe weather events. The data does not support the cause of YCS being a pathogen, specific insect or mite, soil borne agent, poor root health, nutrient deficiency, or heavy metal toxicity. YCS is a physiological disorder visualised as the terminal expression of metabolic perturbances caused by growth disruption
In Reply: Rongeurs, neurosurgeons, and COVID-19: how do we protect health care personnel during neurosurgical operations in the midst of aerosol-generation from high-speed drills?
To the Editor:
We appreciated the manuscript by Chan et al,“Rongeurs, Neurosurgeons, and COVID-19: How Do We Protect Health Care Personnel During Neurosurgical Operations in the Midst of Aerosol-Generation From High-Speed Drills?” published April 2020 in Neurosurgery. We are grateful to the authors of the letter1 for their precise analysis and useful recommendations to fellow neurosurgeons and trainees to uphold the traditional craft of using hand drills and rongeurs in order to minimize aerosol generation from the neurosurgical-powered instruments during the COVID-19 pandemic. Nevertheless, we write in reply to present our surgical experience during the COVID-19 pandemic
A DECISION SUPPORT SYSTEM FOR SUSTAINABLE OPERATIONS MANAGEMENT IN SMALL POWER PLANTS
The importance of environmentally-friendly electricity production is recognized as one of the most important challenges of our future, covering a broad context of research topics and promoting future scenarios based on renewable energies and new technologies. In the short term, however, energy generation will still be largely relying on power plants fired with fossil fuels whose emissions of pollutants are regulated by the industrial emissions directive in the EU legislation. Such directive does not apply to small and medium combustion plants, which until now, have only been subject to national regulations. As part of its air quality package from December 2013, the EU Commission has proposed a new directive which forces such plants to provide periodic measurements of pollutants, keep records of their environmental impact and provide information to the competent authorities. This situation has renewed the attention towards the systems for continuous emission monitoring in SMC. Such systems are in fact very expensive, therefore they require an optimized design in order be affordable for a SMC. This research, in particular, refers to the context of micro-grids and isolated power generation plants based on a set of diesel engine generators (GenSet) and addresses the topic of the development decision support systems (DSS) for environmentally-friendly power genset management. The system is based on a Selective Catalytic Reduction (SCR) reactor coupled with continuous emission monitoring system (CEMS) to reduce the environmental impact and generate information to support the management processes. The paper also reports the preliminary experimental results obtained in the power plant located in the small island of Favignana in the Mediterranean sea. These results demonstrate how the system developed and the approach proposed reduces the emission of pollutants with a substantial benefit for the local community, in a context where more environmentally efficient production technologies can hardly be employed
Intramedullary craniovertebral junction metastasis leading to the diagnosis of underlying renal cell carcinoma
Background: Intramedullary spinal cord metastases represent 4–8.5% of the central nervous system metastases and affect only 0.1–0.4% of all patients. Those originating from renal cell carcinoma (RCC) are extremely rare. Of the eight patients described in the literature with metastatic RCC and intramedullary cord lesion, only five were found in the cervical spine. Here, the authors add a 6th case involving an RCC intramedullary metastasis at the C1–C2 level.
Case Description: A 78-year-old male patient presented with intermittent cervicalgia of 5 months duration accompanied by few weeks of a progressive severe right hemiparesis, up to hemiplegia. The magnetic resonance imaging (MRI) examination revealed an intramedullary expansive lesion measuring 10 mm×15 mm at the C1–C2 level; it readily enhanced with contrast. A total body computed tomography (CT) scan documented an 85 mm mass involving the right kidney, extending to the ipsilateral adrenal gland, and posteriorly infiltrating the ipsilateral psoas muscle. The subsequent CT-guided fine-needle biopsy confirmed the diagnosis of an RCC (Stage IV). The patient next underwent total surgical total removal of the C1–C2 intramedullary mass, following which he exhibited a slight motor improvement, with the right hemiparesis (2/5). He died after 14 months due to global RCC tumor progression.
Conclusion: The present case highlights that a patient without a prior known diagnosis of RCC may present with an intramedullary C1–C2 metastasis. In such cases, global staging is critical to determine whether primary lesion resection versus excision of metastases (e.g., in this case, the C1–C2 intramedullary tumor) are warrante
Incremental value of ePLAR – echocardiographic Pulmonary to Left Atrial Ratio – in the diagnosis of chronic thromboembolic pulmonary hypertension
In Reply: neurosurgery and coronavirus (COVID-19) epidemic: doing our part
To the Editor:
We appreciated the Letter, “Letter: Neurosurgery and Coronavirus (COVID-19) Epidemic: Doing Our Part” by Pesce et al, published in April 2020 in Neurosurgery.
We are grateful to the authors of the Letter for their clear analysis of some neurosurgical procedures in the COVID-19 era. Everyone in the neurosurgical community and in the whole medical community is doing their own part to face this terrible pandemic. Specifically, we would like to present our experience with patients needing a lumbar function or a neuroimaging. We already described our strategy for all emergency patients in an article published in Neurosurgery in April 2020 entitled “In Reply: Rongeurs, Neurosurgeons, and COVID-19: How Do We Protect Health Care Personnel During Neurosurgical Operations in the Midst of Aerosol-Generation From High-Speed Drills?
03-21-1988 Correspondence from Scalia to Rehnquist
Dear Chief,
I share Tony\u27s concerns. Could not our discussion of Rose v . Rose do the job well enough
- …