605 research outputs found
Recommended from our members
Le Dinamiche Temporali della Condivisone di Conoscenza in contesti di lavoro virtuale: uno studio empirico longitudinale
La gestione della conoscenza aziendale viene ormai unanimemente riconosciuta dagli studiosi di economia aziendale come unâimportante leva strategica e competitiva per lâimpresa. Tuttavia, nonostante lo sforzo di ricerca profuso sul tema in questi anni, sembra che in letteratura non si siano ancora formate opinioni condivise e stabili circa le modalitĂ piĂč efficaci di gestione, misurazione e valutazione delle conoscenze in azienda. Di contro, gli studi in materia sembrano essere spesso divisi da opinioni divergenti e talvolta opposte sul concetto stesso di conoscenza cui fare riferimento e sugli obiettivi analitici da assegnare alla ricerca scientifica sul tema. Si ritiene che le divergenze analitiche ed epistemologiche che fino ad oggi hanno caratterizzato la letteratura aziendale sul Knowledge Management costituiscano un limite piĂč che unâopportunitĂ al fine di favorire unâefficace comprensione e gestione della conoscenza aziendale da parte del mondo manageriale. A nostro parere, infatti, il top management e i principali livelli direzionali aziendali potrebbero beneficiare di una lettura integrata e organica dei diversi contributi offerti sul tema dalla letteratura accademica, con particolare riferimento alle tecniche di misurazione della conoscenza. Al fine di delineare i primi elementi di questa prospettiva integrata, in vista di una sistematizzazione unitaria dei diversi approcci al tema, in questo lavoro discuteremo i risultati di un caso empirico di Knowledge Management aziendale. Per fare questo, il presente lavoro Ăš stato articolato in due momenti, il primo di analisi teorica, il secondo di analisi empirica. Il primo momento consiste in unâanalisi dei principali approcci al tema del Knowledge Management emersi nella letteratura aziendale, al fine di metterne in luce limiti e opportunitĂ . Il secondo momento consiste nellâesposizione e discussione delle evidenze empiriche riscontrate sul campo. Nelle conclusioni verranno discusse alcune possibili implicazioni pratiche e teoriche dellâindagine empirica
Intramedullary craniovertebral junction metastasis leading to the diagnosis of underlying renal cell carcinoma
Background: Intramedullary spinal cord metastases represent 4â8.5% of the central nervous system metastases and affect only 0.1â0.4% 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 C1âC2 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 mmĂ15 mm at the C1âC2 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 C1âC2 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 C1âC2 metastasis. In such cases, global staging is critical to determine whether primary lesion resection versus excision of metastases (e.g., in this case, the C1âC2 intramedullary tumor) are warrante
Variazione degli stock di carbonio del suolo in seguito ai processi di abbandono dei coltivi: il caso studio dell\u2019isola di Pantelleria (TP)
The recent abandonment of marginal agricultural areas in the Mediterranean has caused an increase of the surface occupied by pre-forest and forest formations. In order to study the carbon accumulation processes on Pantelleria Island was selected a North-facing area. This area includes 5 stages of succession (sds) that compose a chronosequence (from 0 to 30 years) to understand soil C accumulation processes after abandonment. These are abandoned vineyards or caperbushes, not disturbed (grazing, fire) since agricultural abandonment, and they are situated in thermomediterranean belt and on the same parent material and consequently considered in the same ecological conditions. Samples at 1 cm, 10 cm and 40 cm depth, respectively, were taken for every sds in three different soil relief areas. Litter samples were taken too. Organic carbon content was determined for every sample. Carbon content increases from a sds to the next one. There is a duplication of C from sds0 (cultivated field) to sd1 (abandoned since few years) and from sds4 (abandoned since 16-30 years) to sds5 (abandoned since > 30 years). It seems that different types of vegetation play a key-role in soil C dynamics and there are 85 t C ha-1 in the top 40 cm of the soil after 30 years from the abandonment in the chronosequence and an annual C sequestration rate equal to 3.4 t ha-1. These results show that revegetation offers good opportunities to sequestrate CO2 from the atmosphere and, therefore, to mitigate the greenhouse effect as it is requested by international agreements
Visual Object Tracking in First Person Vision
The understanding of human-object interactions is fundamental in First Person Vision (FPV). Visual tracking algorithms which follow the objects manipulated by the camera wearer can provide useful information to effectively model such interactions. In the last years, the computer vision community has significantly improved the performance of tracking algorithms for a large variety of target objects and scenarios. Despite a few previous attempts to exploit trackers in the FPV domain, a methodical analysis of the performance of state-of-the-art trackers is still missing. This research gap raises the question of whether current solutions can be used âoff-the-shelfâ or more domain-specific investigations should be carried out. This paper aims to provide answers to such questions. We present the first systematic investigation of single object tracking in FPV. Our study extensively analyses the performance of 42 algorithms including generic object trackers and baseline FPV-specific trackers. The analysis is carried out by focusing on different aspects of the FPV setting, introducing new performance measures, and in relation to FPV-specific tasks. The study is made possible through the introduction of TREK-150, a novel benchmark dataset composed of 150 densely annotated video sequences. Our results show that object tracking in FPV poses new challenges to current visual trackers. We highlight the factors causing such behavior and point out possible research directions. Despite their difficulties, we prove that trackers bring benefits to FPV downstream tasks requiring short-term object tracking. We expect that generic object tracking will gain popularity in FPV as new and FPV-specific methodologies are investigated
Surveillance for Hepatocellular Carcinoma in Patients with Non-Alcoholic Fatty Liver Disease: Universal or Selective?
Hepatocellular carcinoma (HCC), the most frequent primary liver cancer, is the sixth most common cancer, the fourth leading cause of cancer-related deaths worldwide, and accounts globally for about 800,000 deaths/year. Early detection of HCC is of pivotal importance as it is associated with improved survival and the ability to apply curative treatments. Chronic liver diseases, and in particular cirrhosis, are the main risk factors for HCC, but the etiology of liver disease is rapidly changing due to improvements in the prevention and treatment of HBV (Hepatitis B virus) and HCV (Hepatitis C virus) infections and to the rising incidence of the metabolic syndrome, of which non-alcoholic fatty liver (NAFLD) is a manifestation. NAFLD is now a recognized and rapidly increasing cause of cirrhosis and HCC. Indeed, the most recent guidelines for NAFLD management recommend screening for HCC in patients with established cirrhosis. Screening in NAFLD patients without cirrhosis is not recommended; however, the prevalence of HCC in this group of NAFLD patients has been reported to be as high as 38%, a proportion significantly higher than the one observed in the general population and in non-cirrhotic subjects with other causes of liver disease. Unfortunately, solid data regarding the risk stratification of patients with non-cirrhotic NAFLD who might best benefit from HCC surveillance are scarce, and specific recommendations in this field are urgently needed due to the increasing NAFLD epidemic, at least in Western countries. To further complicate matters, liver ultrasonography, which represents the current standard for HCC surveillance, has a decreased diagnostic accuracy in patients with NAFLD, and therefore disease-specific surveillance tools will be required for the early identification of HCC in this population. In this review, we summarize the most recent evidence on the epidemiology and risk factors for HCC in patients with NAFLD, with and without cirrhosis, and the evidence supporting surveillance for early HCC detection in these patients, reviewing the potential limitations of currently recommended surveillance strategies, and assessing data on the accuracy of potential new screening tools. At this stage it is difficult to propose general recommendations, and best clinical judgement should be exercised, based on the profile of risk factors specific to each patient
Forecasting Human-Object Interaction: Joint Prediction of Motor Attention and Actions in First Person Video
We address the challenging task of anticipating human-object interaction in
first person videos. Most existing methods ignore how the camera wearer
interacts with the objects, or simply consider body motion as a separate
modality. In contrast, we observe that the international hand movement reveals
critical information about the future activity. Motivated by this, we adopt
intentional hand movement as a future representation and propose a novel deep
network that jointly models and predicts the egocentric hand motion,
interaction hotspots and future action. Specifically, we consider the future
hand motion as the motor attention, and model this attention using latent
variables in our deep model. The predicted motor attention is further used to
characterise the discriminative spatial-temporal visual features for predicting
actions and interaction hotspots. We present extensive experiments
demonstrating the benefit of the proposed joint model. Importantly, our model
produces new state-of-the-art results for action anticipation on both EGTEA
Gaze+ and the EPIC-Kitchens datasets. Our project page is available at
https://aptx4869lm.github.io/ForecastingHOI
Recommended from our members
Exploring the topology of the plausible: Fs/QCA counterfactual analysis and the plausible fit of unobserved organizational configurations
The main aim of this contribution is to expand the dominant rationale of organizational design research by including solutions and possibilities not observed in reality. We believe that the
counterfactual approach to configurations responds to an open call in organization theory and strategy to move the modelling of fit towards a more robust and theory-based specification. With this new approach we propose to rediscover the roots of organization design as a distinct normative discipline that âshould stand approximately in relation to the basic social sciences as engineering stands with respect to physical sciences or medicine to the biologicalâ. At a more general level, our view implies an expansion of the dominant meaning of the concept of ârelevanceâ in management research. While we agree with Gulati (2007: 780) that we as scholars should probe âmore deeply into the problems and other issues that managers care aboutâ, we also believe that relevance does not necessarily mean that researchers have to use an ex-post rationality by studying only empirically frequent phenomena. In contrast, we think that any management esearcher should bring with her or himself a fragment of the spirit
of the great Greek philosopher Anaximander (c. 610âc. 546 BC), who foresaw the concept of the infinite universe without the support of any empirical observation and against the predominant
wisdom of the time. Not by chance, Karl Popper (1998) onsidered Anaximanderâs intuitions among the most vivid demonstrations of the power of human thought and logic
hepatocellular carcinoma is the most frequent final diagnosis of focal liver lesions identified in a cross sectional evaluation of patients with chronic liver disease in saudi arabia
Background.Hepatocellular carcinoma (HCC) is a frequent diagnosis in patients with chronic liver disease (CLD) and a newly identified liver lesion, although benign diseases may also be responsible for this finding.Objective.To evaluate the characteristics of focal liver lesions in a population of patients with CLD not under surveillance for HCC in the Middle East.Methods.We performed a cross-sectional study evaluating 77 patients with CLD and a focal liver lesion identified during ultrasonography. Patients' characteristics were analyzed on the basis of the final diagnosis (HCC versus benign lesions).Results.The most frequent diagnosis was HCC (64.9%). These patients were older (median age 64 versus 55 years,P=0.003) and cirrhotics (80.0% versus 51.9%,P=0.018), with multinodular lesions (58.0% versus 29.6%,P=0.031) and portal vein thrombosis (24.0% versus 0%,P=0.001) compared to patients with benign lesions. Prevalence of elevated alpha-fetoprotein (>10âng/mL) was similar in both groups (80.0% versus 88.9%,P=0.198). Cirrhosis (odds ratio: 3.283) and multinodularity (odds ratio: 2.898) were independently associated with HCC.Conclusions.HCC is the most common diagnosis in Middle-Eastern patients with CLD and a liver lesion identified outside HCC surveillance programs, especially in cirrhotic patients. In these patients, elevated alpha-fetoprotein does not differentiate HCC from benign lesions
Mediterranean Diet and NAFLD: What We Know and Questions That Still Need to Be Answered
open8Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and is expected to become the leading cause of end-stage liver disease worldwide over the next few decades. In fact, NAFLD encompasses different clinical scenarios, from the simple accumulation of fat (steatosis) to steatohepatitis (NASH), NASH-cirrhosis, and cirrhosis complications. In this context, it is fundamental to pursue strategies aimed at both preventing the disease and reducing the progression of liver fibrosis once liver damage is already initiated. As of today, no pharmacological treatment has been approved for NAFLD/NASH, and the only recommended treatment of proven efficacy are life-style modifications, including diet and physical exercise pointing at weight loss of 5%-7%. Different dietetic approaches have been proposed in this setting, and in this review, we will discuss the evidence regarding the efficacy of the Mediterranean Diet as a treatment for NAFLD. In particular, we will report the effects on liver-related outcomes.openPlaz Torres, Maria Corina; Aghemo, Alessio; Lleo, Ana; Bodini, Giorgia; Furnari, Manuele; Marabotto, Elisa; Miele, Luca; Giannini, Edoardo GPlaz Torres, Maria Corina; Aghemo, Alessio; Lleo, Ana; Bodini, Giorgia; Furnari, Manuele; Marabotto, Elisa; Miele, Luca; Giannini, Edoardo
Optimal management of constipation associated with irritable bowel syndrome
Irritable bowel syndrome (IBS) is a common chronic functional disorder of the gastrointestinal tract, meanly characterized by recurrent abdominal pain or discomfort and altered bowel habit. It is a complex disorder involving biological, environmental, and psychosocial factors. The diagnosis is achieved according to the Rome III criteria provided that organic causes have been excluded. Although IBS does not constitute a life-threatening condition, it has a remarkable prevalence and profoundly reduces the quality of life with burdening socioeconomic costs. One of the principal concerns about IBS is the lack of effective therapeutic options. Up to 40% of patients are not satisfied with any available medications, especially those suffering from chronic constipation. A correct management of IBS with constipation should evolve through a global approach focused on the patient, starting with careful history taking in order to assess the presence of organic diseases that might trigger the disorder. Therefore, the second step is to examine lifestyle, dietary habits, and psychological status. On these bases, a step-up management of disease is recommended: from fiber and bulking agents, to osmotic laxative drugs, to new molecules like lubiprostone and linaclotide. Although new promising tools for relief of bowel-movement-related symptoms are being discovered, a dedicated doctor-patient relationship still seems to be the key for success
- âŠ