Slipped Capital Femoral Epiphysis. A Report of 4 Cases Occurring in One Family

We describe slipped capital femoral epiphysis in 4 members of a black, obese family, who were all first-degree relatives. The aetiology of slipped capital femoral epiphysis is unknown, although it is thought to be multifactorial. Genetic predisposition and environmental factors have been associated with the condition. A familial incidence with at least two cases in the same family has been reported. In epidemiological studies, this incidence ranges from 3% to 35%. Our cases were investigated in an attempt to find a possible aetiological genetic factor. A genetic predisposition with an autosomal dominant pattern of transmission is suggested, although environmental variables must be considered as provocative factors

Verifying Strong Eventual Consistency in Distributed Systems

Data replication is used in distributed systems to maintain up-to-date copies of shared data across multiple computers in a network. However, despite decades of research, algorithms for achieving consistency in replicated systems are still poorly understood. Indeed, many published algorithms have later been shown to be incorrect, even some that were accompanied by supposed mechanised proofs of correctness. In this work, we focus on the correctness of Conflict-free Replicated Data Types (CRDTs), a class of algorithm that provides strong eventual consistency guarantees for replicated data. We develop a modular and reusable framework in the Isabelle/HOL interactive proof assistant for verifying the correctness of CRDT algorithms. We avoid correctness issues that have dogged previous mechanised proofs in this area by including a network model in our formalisation, and proving that our theorems hold in all possible network behaviours. Our axiomatic network model is a standard abstraction that accurately reflects the behaviour of real-world computer networks. Moreover, we identify an abstract convergence theorem, a property of order relations, which provides a formal definition of strong eventual consistency. We then obtain the first machine-checked correctness theorems for three concrete CRDTs: the Replicated Growable Array, the Observed-Remove Set, and an Increment-Decrement Counter. We find that our framework is highly reusable, developing proofs of correctness for the latter two CRDTs in a few hours and with relatively little CRDT-specific code

A Highly-Available Move Operation for Replicated Trees

Replicated tree data structures are a fundamental building block of distributed filesystems, such as Google Drive and Dropbox, and collaborative applications with a JSON or XML data model. These systems need to support a move operation that allows a subtree to be moved to a new location within the tree. However, such a move operation is difficult to implement correctly if different replicas can concurrently perform arbitrary move operations, and we demonstrate bugs in Google Drive and Dropbox that arise with concurrent moves. In this paper we present a CRDT algorithm that handles arbitrary concurrent modifications on trees, while ensuring that the tree structure remains valid (in particular, no cycles are introduced), and guaranteeing that all replicas converge towards the same consistent state. Our algorithm requires no synchronous coordination between replicas, making it highly available in the face of network partitions. We formally prove the correctness of our algorithm using the Isabelle/HOL proof assistant, and evaluate the performance of our formally verified implementation in a geo-replicated setting.The Boeing Company; EPSRC “REMS: Rigorous Engineering for Mainstream Systems” programme grant (EP/K008528); Leverhulme Trust Early Career Fellowship, Isaac Newton Trust; Nokia Bell Labs

Interleaving anomalies in collaborative text editors

Collaborative text editors allow two or more users to concurrently edit a shared document without merge conflicts. Such systems require an algorithm to provide convergence, ensuring all clients that have seen the same set of document edits are in the same state. Unfortunately convergence alone does not guarantee that a collaborative text editor is usable. Several published algorithms for collaborative text editing exhibit an undesirable anomaly in which concurrently inserted portions of text with a well-defined order may be randomly interleaved on a character-by-character basis, resulting in an unreadable jumble of letters. Although this anomaly appears to be known informally by some researchers in the field, we are not aware of any published work that fully explains or addresses it. We show that several algorithms suffer from this problem, explain its cause, and also identify a lesser variant of the anomaly that occurs in another algorithm. Moreover, we propose a specification of collaborative text editing that rules out the anomaly, and show how to prevent the lesser anomaly from occurring in one particular algorithm.The Boeing Company and EPSRC “REMS: Rigorous Engineering for Mainstream Systems” programme grant (EP/K008528)

Fenómeno de Raynaud com isquémia acral – um caso de crioglobulinémia essencial

info:eu-repo/semantics/publishedVersio

Kaposi’s sarcoma, case report

O Sarcoma de Kaposi (SK) é um distúrbio angioproliferativo descrito como doença benigna de pessoas idosas. Divide- se em 4 tipos: O Clássico, epidémico, endêmico e iatrogénico. Os autores descrevem o caso de um homem caucasiano de 50 anos, português, que iniciou a sintomatologia 6 anos antes do internamento com lesões urticariformes na perna direita e perda ponderal de 10 kg em 6 meses. Por agravamento das lesões e aparecimento de púrpura nos membros inferiores recorreu ao hospital. O exame objetivo era normal à exceção de púrpuras dispersas com relevo, descamativas e violáceas na região plantar e restante membros inferiores, membros superiores e tronco. As serologias para o HIV 1 e 2 foram negativas a serologia viral para o Herpes virus humano 8 IGG foi positivo, PCR H8 positivo, a biópsia das lesões com histologia foi compatível com Sarcoma de Kaposi. Iniciou o 1º ciclo de Doxorrubicina lipossómica peguilhada e manteve seguimento em Hospital dia de Oncologia.info:eu-repo/semantics/publishedVersio

Scaling in a post-growth era: Learning from Social Agricultural Cooperatives

This is the final version. Available from SAGE Publications via the DOI in this record. It has become normative in organization and management studies literature to consider scaling as a synonym for organizational growth. Scaling is typically understood as scaling-up. This article demonstrates that, in the context of post-growth organizations, scaling involves a more complex set of dynamics. Directing scholarly attention to scaling in the context of Italian Social Agricultural Cooperatives (i.e. organizations that hold a different rationale and modus operandi from the capitalist enterprise), this research contributes to the literature on scaling the impact of post-growth organizations by identifying nine different scaling routes: organizational growth (vertical and horizontal); organizational downscaling; impact on policies; multiplication; impact on organizational culture; impact on societal culture; aggregation; and diffusion. This article demonstrates that post-growth scaling: (1) requires the synergistic interaction of different strategies; (2) focuses on impacting societal culture; (3) does not necessarily require organizational growth; and (4) is a relational process, embedded in socio-ecological systems. The typology presented in this article empowers post-growth organizations to become more aware of different available scaling routes, unlocking their transformative potential and supporting the transition towards a post-growth future, in which the goal of economics is the pursuit of human and ecological flourishing

Upturn in secondary forest clearing buffers primary forest loss in the Brazilian Amazon

Brazil contains two-thirds of remaining Amazonian rainforests and is responsible for the most Amazon forest loss. Primary forest loss in the Brazilian Amazon has declined considerably since 2004 but secondary forest loss has never been quantified. We use a recently developed high-resolution land use/land cover dataset to track secondary forests in the Brazilian Amazon over 14 yr, providing the first estimates of secondary forest loss for the region. We find that secondary forest loss increased by (187 ± 48)% from 2008 to 2014. Moreover, the proportion of total forest loss accounted for by secondary forests rose from (37 ± 3)% in 2000 to (72 ± 5)% in 2014. The recent acceleration in secondary forests loss occurred across the entire region and was not driven simply by increasing secondary forest area but probably a conscious preferential shift towards clearance of a little-protected forest ecosystem (secondary forests). Our results suggest that secondary forests loss has eased deforestation pressure on primary forests. However, this has been at the expense of a lost carbon sequestration opportunity of 2.59–2.66 Pg C over our study period

Influence of P53 on the radiotherapy response of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and it has a poor prognosis and few therapeutic options. Radiotherapy is one of the most effective forms of cancer treatment, and P53 protein is one of the key molecules determining how a cell responds to radiotherapy. The aim of this study was to determine the therapeutic efficacy of iodine-131 in three human HCC cell lines