Systolic array network processors represent an effective alternative to ASICs for the design of multi-gigabit packet switching and forwarding devices because of their flexibility, high aggregate ...throughput and deterministic worst-case performances. However such advantages come at the expense of some limitations, given both by the specific characteristics of the pipelined architecture and by the lack of support for portable high-level languages in the software development tools, forcing software engineers to deal with low level aspects of the underlying hardware platform. In this paper we present a set of techniques that have been implemented in the Network Virtual Machine (NetVM) compiler infrastructure for mapping general layer 2-3 packet processing applications on the Xelerated X11 systolic-array network processor. In particular we demonstrate that our compiler is able to effectively exploit the available hardware resources and to generate code that is comparable to hand-written one, hence ensuring excellent throughput performances.
Over the past 10 years, the grafting of polymers from the surface of cellulose nanocrystals (CNCs) has gained substantial interest in both academia and industry due to the rapidly growing number of ...potential applications of surface-modified CNCs, which range from building blocks in nanocomposites and responsive nanomaterials to antimicrobial agents. CNCs are rod-like nanoparticles that can be isolated from renewable biosources and which exhibit high crystallinity, tunable aspect ratio, high stiffness, and strength. Upon drying, the abundance of surface hydroxyl groups often leads to a degree of irreversible aggregation, as a result of strong hydrogen bonding. Moreover, their relatively hydrophilic character renders CNCs incompatible with hydrophobic media, e.g., nonpolar solvents and polyolefin matrices. By grafting macromolecules from their surface, CNCs can be imparted with surface characteristics and other physicochemical properties that are reminiscent of the grafted polymer. This has allowed the design of nanoscale building blocks whose readily tunable properties are useful for the formation of both colloidal dispersions and solid state materials. In this Perspective, we provide an overview of the morphology and surface chemistry of CNCs and detail various techniques to manipulate their surface chemistry via polymer grafting from approaches. Moreover, we explore the most common polymerization techniques that are used to graft polymers from the surface and reducing end groups of CNCs, including surface-initiated ring-opening polymerization (SI-ROP), surface-initiated free (SI-FRP), and controlled (SI-CRP) radical polymerization. Finally, we provide insights into some of the emerging applications and conclude with an outlook of future work that would benefit the field.
335 inguino-femoral hernias were repaired with polypropylene mesh from December 1991 through December 1995. Eleven patients underwent mesh reinforced Bassini, 167 modified Lichtenstein's technique ...and 108 Trabucco's repair. Forty-three patients were treated under regional anesthesia. Bilateral hernia was diagnosed in 33 patients and in 20 out of 33 the surgical procedure was entirely performed under regional anesthesia. Early complications referred were 32 scrotal hematomas which spontaneously healed. Two patients showed a recidive hernia and were retreated with and additional mesh; plug rejection (early experience) was referred in one patient who was reoperated on employing a mesh. The indications for the more suitable technique were directly deducted from Nyhus' hernia classification. The authors finally point out the: 1) importance of regional inguinal anesthesia; 2) correct cutting and application of the mesh in the inguinal canal; 3) internal inguinal ring repair; 4) bilateral hernia repair under regional anesthesia.
The authors examine 192 consecutive cases of upper gastrointestinal hemorrhage; the series included 133 males and 59 females with a mean age of 55.78 years (SD +/- 17.88) and range of 18-97. All ...patients underwent emergency esophagogastroduodenoscopy within 6-12 hours of hospitalisation. Adequate infusion and; when necessary, transfusion therapy associated with protection using anti H2 (ranitidine 200 mg/24 h) and octreotide (0.2 mg x 3/day sc), proportionately scaled over the following 72 hours, were used in all patients. Nasogastric aspiration (nasogastric probe or Sengstaken-Blakemore probe) were used for at most 48 h after endoscopy. Patients were then subdivided into 2 age groups: under (104 cases) and over (88 cases) 60 years. Statistical relations were studied (Chi-square test), assuming the reference value to be p = 5%, between age and diagnosis, sex, symptoms on presentation, hemotransfusion, Forrest's classification, the onset of renewed bleeding and lastly the evolution of each case. Hemorrhage was more frequent in males aged < 60 years and in females aged > 60 (p < 0.004), hemorrhagic shock, the presence of Forrest 1a and 1b and death were significant in elderly subjects (p < 0.004; p < 0.01; p < 0.01). The latter finding included patients with esophageal varices, group which was significantly correlated with mortality independent of age. The overlap of statistical results in hemorrhage not related to varices suggests, on the one hand, that appropriate early treatment has a greater influence on the prognosis rather than the type of pathology, and on the other that being aged over 60 does not correspond to an increased biological risk.
The authors examine eight cases of acute pseudo-obstruction of the colon and point out that these may be inserted in the wider context of intestinal pseudo-obstructions. These comments raise ...questions concerning Ogilvie's syndrome since the dilatations observed do not only affect the colon, according to the classic definition, but also the ileo-jejunal tract, in spite of the fact that the main target continues to be the colon. The term Ogilvie's syndrome is still significant in the clinical identification of colic dilatation, in particular the right colon in which possible complications are more severe. The authors identify colonoscopy as the best instrumental test owing to the possibilities its offers, including therapeutic, and also underline that there does not appear to be a real risk of iatrogenic lesions if an appropriate technique is used.
The authors report three cases of acute epiploitis diagnosed intraoperatively and discuss the etiopathogenetic hypotheses. They suggest a relationship between acute epiploitis and mesenteric ...lymphadenitis, as well as their common origin.
Acute intestinal ischemia is a pathology which is relatively often encountered in elderly patients where the concomitance of other diseases make its prognosis more severe, especially since diagnosis ...is usually late. Laboratory tests and imaging techniques are not of great value to diagnosis since they do not provide pathognomonic data, but together with a careful anamnesis they contribute a series of findings which, taken as a whole, lead to the diagnosis of intestinal ischemia. The sole therapy is surgery--when still possible and the best results are obtained when surgery is performed at an early stage. The authors report a series of 12 cases of acute intestinal ischemia and underline the difficulty of diagnosing this subtle pathology and the advantages of aggressive surgical techniques.
Critical illness is associated with cognitive impairment, but mental health and functional disabilities in survivors of intensive care are inadequately characterised. We aimed to assess associations ...of age and duration of delirium with mental health and functional disabilities in this group.
In this prospective, multicentre cohort study, we enrolled patients with respiratory failure or shock who were undergoing treatment in medical or surgical ICUs in Nashville, TN, USA. We obtained data for baseline demographics and in-hospital variables, and assessed survivors at 3 months and 12 months with measures of depression (Beck Depression Inventory II), post-traumatic stress disorder (PTSD, Post-Traumatic Stress Disorder Checklist-Event Specific Version), and functional disability (activities of daily living scales, Pfeffer Functional Activities Questionnaire, and Katz Activities of Daily Living Scale). We used linear and proportional odds logistic regression to assess the independent associations between age and duration of delirium with mental health and functional disabilities. This study is registered with ClinicalTrials.gov, number NCT00392795.
We enrolled 821 patients with a median age of 61 years (IQR 51-71), assessing 448 patients at 3 months and 382 patients at 12 months after discharge. At 3 months, 149 (37%) of 406 patients with available data reported at least mild depression, as did 116 (33%) of 347 patients at 12 months; this depression was mainly due to somatic rather than cognitive-affective symptoms. Depressive symptoms were common even among individuals without a history of depression (as reported by a proxy), occurring in 76 (30%) of 255 patients with data at 3 months and 62 (29%) of 217 individuals at 12 months. Only 7% of patients (27 of 415 at 3 months and 24 of 361 at 12 months) had symptoms consistent with post-traumatic distress disorder. Disabilities in basic activities of daily living (ADL) were present in 139 (32%) of 428 patients at 3 months and 102 (27%) of 374 at 12 months, as were disabilities in instrumental ADL in 108 (26%) of 422 individuals at 3 months and 87 (23%) of 372 at 12 months. Mental health and functional difficulties were prevalent in patients of all ages. Although old age was frequently associated with mental health problems and functional disabilities, we observed no consistent association between the presence of delirium and these outcomes.
Poor mental health and functional disability is common in patients treated in intensive-care units. Depression is five times more common than is post-traumatic distress disorder after critical illness and is driven by somatic symptoms, suggesting approaches targeting physical rather than cognitive causes could benefit patients leaving critical care.
National Institutes of Health AG027472 and the Geriatric Research, Education and Clinical Center (GRECC), Department of Veterans Affairs Medical Center, Tennessee Valley Healthcare System.
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