A Forward Reachability Algorithm for Bounded Timed-Arc Petri Nets

Timed-arc Petri nets (TAPN) are a well-known time extension of the Petri net model and several translations to networks of timed automata have been proposed for this model. We present a direct, DBM-based algorithm for forward reachability analysis of bounded TAPNs extended with transport arcs, inhibitor arcs and age invariants. We also give a complete proof of its correctness, including reduction techniques based on symmetries and extrapolation. Finally, we augment the algorithm with a novel state-space reduction technique introducing a monotonic ordering on markings and prove its soundness even in the presence of monotonicity-breaking features like age invariants and inhibitor arcs. We implement the algorithm within the model-checker TAPAAL and the experimental results document an encouraging performance compared to verification approaches that translate TAPN models to UPPAAL timed automata.Comment: In Proceedings SSV 2012, arXiv:1211.587

Interobserver agreement for the spine instability neoplastic score varies according to the experience of the evaluator

OBJECTIVES: To evaluate the interobserver agreement for the Neoplastic Spine Instability Score (SINS) among spine surgeons with or without experience in vertebral metastasis treatment and physicians in other specialties. METHODS: Case descriptions were produced based on the medical records of 40 patients with vertebral metastases. The descriptions were then published online. Physicians were invited to evaluate the descriptions by answering questions according to the Neoplastic Spine Instability Score (SINS). The agreement among physicians was calculated using the kappa coefficient. RESULTS: Seventeen physicians agreed to participate: three highly experienced spine surgeons, seven less-experienced spine surgeons, three surgeons of other specialties, and four general practitioners (n = 17). The agreement for the final SINS score among all participants was fair, and it varied according to the SINS component. The agreement was substantial for the spine location only. The agreement was higher among experienced surgeons. The agreement was nearly perfect for spinal location among the spine surgeons who were highly experienced in vertebral metastases. CONCLUSIONS: This study demonstrates that the experience of the evaluator has an impact on SINS scale classification. The interobserver agreement was only fair among physicians who were not spine surgeons and among spine surgeons who were not experienced in the treatment of vertebral metastases, which may limit the use of the SINS scale for the screening of unstable lesions by less-experienced evaluators

Granulocyte Colony-Stimulating Factor Combined with Methylprednisolone Improves Functional Outcomes in Rats with Experimental Acute Spinal Cord Injury

OBJECTIVES: To evaluate the effects of combined treatment with granulocyte colony-stimulating factor (G-CSF) and methylprednisolone in rats subjected to experimental spinal cord injury. METHODS: Forty Wistar rats received a moderate spinal cord injury and were divided into four groups: control (no treatment); G-CSF (G-CSF at the time of injury and daily over the next five days); methylprednisolone (methylprednisolone for 24 h); and G-CSF/Methylprednisolone (methylprednisolone for 24 h and G-CSF at the time of injury and daily over the next five days). Functional evaluation was performed using the Basso, Beattie and Bresnahan score on days 2, 7, 14, 21, 28, 35 and 42 following injury. Motor-evoked potentials were evaluated. Histological examination of the spinal cord lesion was performed immediately after euthanasia on day 42. RESULTS: Eight animals were excluded (2 from each group) due to infection, a normal Basso, Beattie and Bresnahan score at their first evaluation, or autophagy, and 32 were evaluated. The combination of methylprednisolone and G-CSF promoted greater functional improvement than methylprednisolone or G-CSF alone (

Fractures of the cervical spine

OBJECTIVES: The aim of this study was to review the literature on cervical spine fractures. METHODS: The literature on the diagnosis, classification, and treatment of lower and upper cervical fractures and dislocations was reviewed. RESULTS: Fractures of the cervical spine may be present in polytraumatized patients and should be suspected in patients complaining of neck pain. These fractures are more common in men approximately 30 years of age and are most often caused by automobile accidents. The cervical spine is divided into the upper cervical spine (occiput-C2) and the lower cervical spine (C3-C7), according to anatomical differences. Fractures in the upper cervical spine include fractures of the occipital condyle and the atlas, atlanto-axial dislocations, fractures of the odontoid process, and hangman's fractures in the C2 segment. These fractures are characterized based on specific classifications. In the lower cervical spine, fractures follow the same pattern as in other segments of the spine; currently, the most widely used classification is the SLIC (Subaxial Injury Classification), which predicts the prognosis of an injury based on morphology, the integrity of the disc-ligamentous complex, and the patient's neurological status. It is important to correctly classify the fracture to ensure appropriate treatment. Nerve or spinal cord injuries, pseudarthrosis or malunion, and postoperative infection are the main complications of cervical spine fractures. CONCLUSIONS: Fractures of the cervical spine are potentially serious and devastating if not properly treated. Achieving the correct diagnosis and classification of a lesion is the first step toward identifying the most appropriate treatment, which can be either surgical or conservative

Serum sodium disorders in patients with traumatic brain injury

Sodium disorders are the most common and most poorly understood electrolyte disorders in neurological patients. The aim of this study was to determine the incidence of sodium disorders and its association with different traumatic brain injuries. This prospective study was conducted in 80 patients diagnosed with moderate and severe traumatic brain injuries. All patients underwent cerebral computed tomography. Incidence of sodium disorders, presence of injuries in the first computed tomography after traumatic brain injury, and level of consciousness were analyzed. Patients that presented other potential causes of sodium disorders and systemic trauma were excluded from the study. The incidence of sodium disturbances was 45%: 20 patients presented hypernatremia and 16 hyponatremia. Refers to all patients with sodium disturbances 53% were detected in the first sample. We recorded at least one measurement <125 mEq/L in 50% of the patients with hyponatremia. A greater incidence of sodium disorders was found in patients with subdural, intracerebral hematoma and with diffuse axonal injury. The incidence of sodium disorders among the patients with diffuse lesions was greater than in the group of patients with brain contusion (P = 0.022). The incidence of sodium disorders is higher in patients with diffuse traumatic brain injuries. No association was found between focal lesions and proportion of sodium disorders

Effect of recreational beach tennis on ambulatory blood pressure and physical fitness in hypertensive individuals (BAH study) : rationale and study protocol

Background: Different physical activities are widely recommended as non-pharmacological therapies to reduce blood pressure. However, the effectiveness of exercise programs is associated with its continuity and regularity, and the long-term adherence to traditional exercise interventions is often low. Recreational sports emerge as an alternative, being more captivating and able to retain individuals for longer periods. Besides, sport interventions have demonstrated improvements in physical fitness components that are associated with a lower incidence of hypertension. However, no studies have investigated the effects of recreational sports on 24 h ambulatory blood pressure. The aim of the present study is to evaluate the effect of beach tennis training on ambulatory blood pressure and physical fitness in individuals with hypertension. Methods: This study will be a randomized, single-blinded, two-arm, parallel, and superiority trial. Forty-two participants aged 35–65 years with previous diagnosis of hypertension will be randomized to 12 weeks of beach tennis training group (two sessions per week lasting 45–60 min) or a non-exercising control group. Ambulatory (primary outcome) and office blood pressures, cardiorespiratory fitness, muscle strength/power and quality of life will be assessed at baseline and after the intervention period. Discussion: Our conceptual hypothesis is that beach tennis training will reduce ambulatory blood pressure and improve fitness parameters in middle-aged individuals with hypertension. The results of this trial are expected to provide evidences of efficacy of recreational beach tennis practice on blood pressure management and to support sport recommendations for clinical scenario in higher risk populations

En bloc vertebrectomy for the treatment of spinal lesions. Five years of experience in a single institution: a case series

OBJECTIVES: The objective of this study is to describe the experience of a Brazilian public university hospital regarding the treatment of metastatic or benign spine lesions with en bloc vertebrectomy of the thoracic and lumbar spines. METHODS: This study was a retrospective case series and included all medical records of patients with benign aggressive, primary malignant, or metastatic spine lesions who underwent en bloc vertebrectomy from 2010 to 2015. RESULTS: A total of 17 patients were included in the analysis. Most of them (71%) were indicated for surgery based on an oncologic resection for localized disease cure. Overall, 10 of the 17 patients (59%) underwent vertebrectomy via an isolated posterior approach using the technique described by Roy-Camille et al. and Tomita et al., while 7 patients (41%) underwent double approach surgeries. Of the 17 patients who underwent the en bloc resection, 8 are still alive and in the outpatient follow-up (47%), and almost all patients with metastatic lesions (8/9) died. The average survival time following the surgical procedure was 23.8 months. Considering the cases of metastatic lesions and the cases of localized disease (malignant or benign aggressive disease) separately, we observed an average survival time of 15 months and 47.6 months respectively. CONCLUSION: This study demonstrates and reinforces the reproducibility of the en bloc vertebrectomy technique described by Tomita et al