Absorption line series and autoionization resonance structure analysis in the ultraviolet spectrum of Sr I

Photoelectric spectrometer to measure absorption line series and autoionization resonance in ultraviolet spectrum of strontium vapo

Cost-effectiveness analysis of endoscopic third ventriculostomy

Journal ArticleOBJECTIVE: Endoscopic third ventriculostomy (ETV) is currently the principal alternative to cerebrospinal fluid shunt placement in the management of pediatric hydrocephalus. Cost-effectiveness analysis can help determine the optimal strategy for integrating these different approaches. METHODS: All patients (n = 28) who underwent ETV at British Columbia's Children's Hospital between 1989 and 1998 were matched for age, pathogenesis, and number of previous shunt procedures, with patients treated with cerebrospinal fluid shunts. To perform a cost-effectiveness analysis, hydrocephalus-related resource consumption and outcome (determined as the number of hydrocephalus treatment-free days during follow-up) were then retrospectively identified. Cost data were linked to resource use to provide a total cost for all resources used. Costs and outcomes were discounted annually at 5% by standard economic analysis methods. RESULTS: Twenty-four of 28 ETV patients had obstructive hydrocephalus. Over equivalent follow-up periods (median, 35 mo), the ETV success rate (defined by need for reoperation) was 54%.One hydrocephalus-related death and one hemiparesis occurred in the ETV group. No permanent procedure-related morbidity or mortality was seen in the shunt group. The cost/effect ratios for the two groups were similar. The additional incremental resource use by the shunt group included six readmissions and eight reoperations. ETV mean costs per patient were $10,570 ±$7628, versus $10,922 ±$8722 for the shunt group (Canadian dollars for the year 2000). Costs accrued more quickly for the shunt group as time passed. The additional incremental outcome benefit to the endoscopy group was 86 treatment-free days (3.07 d per patient [95% confidence interval, -7.56 to 13.70 d]). Neither of these differences was statistically significant. CONCLUSION: In this matched cohort, ETV was not significantly less costly or more effective over a median 35 months of follow-up, with a 54% initial ETV success rate, even before the additional morbidity and mortality encountered were taken into account. The time course for the accrued costs suggests that a larger cohort, longer follow-up, or higher success rates are needed to demonstrate the cost-effectiveness of this therapy

Predicting shunt failure on the basis of clinical symptoms and signs in children

Journal ArticleObject. In evaluating pediatric patients for shunt malfunction, predictive values for symptoms and signs are important in deciding which patients should undergo an imaging study, whereas determining clinical findings that correlate with a low probability of shunt failure could simplify management. Methods. Data obtained during the recently completed Pediatric Shunt Design Trial (PSDT) were analyzed. Predictive values were calculated for symptoms and signs of shunt failure. To refine predictive capability, a shunt score based on a cluster of signs and symptoms was derived and validated using multivariate methods. Four hundred thirty-one patient encounters after recent shunt insertions were analyzed. For encounters that took place within 5 months after shunt insertion (early encounters), predictive values for symptoms and signs included the following: nausea and vomiting (positive predictive value [PPV] 79%, likelihood ratio [LR] 10.4), irritability (PPV 78%, LR 9.8), decreased level of consciousness (LOC) (PPV 100%), erythema (PPV 100%), and bulging fontanelle (PPV 92%, LR 33.1). Between 9 months and 2 years after shunt insertion (late encounters), only loss of developmental milestones (PPV 83%, LR 36.7) and decreased LOC (PPV 100%) were strongly associated with shunt failure. However, the absence of a symptom or sign still left a 15 to 29% (early encounter group) or 9 to 13% (late encounter group) chance of shunt failure. Using the shunt score developed for early encounters, which sums from 1 to 3 points according to the specific symptoms or signs present, patients with scores of 0, 1, 2, and 3 or greater had shunt failure rates of 4%, 50%, 75%, and 100%, respectively. Using the shunt score derived from late encounters, patients with scores of 0, 1, and 2 or greater had shunt failure rates of 8%, 38%, and 100%, respectively. Conclusions. In children, certain symptoms and signs that occur during the first several months following shunt insertion are strongly associated with shunt failure; however, the individual absence of these symptoms and signs offers the clinician only a limited ability to rule out a shunt malfunction. Combining them in a weighted scoring system improves the ability to predict shunt failure based on clinical findings

Management of shunt infections: a multicenter pilot study

Journal ArticleObject. Approximately 10% of cerebrospinal fluid (CSF) shunt operations are associated with infection and require removal or externalization of the shunt, in-hospital treatment with antibiotic agents, and insertion of a new shunt. In a previous survey, the authors identified substantial variation in the duration of antibiotic therapy as well as the duration of hospital stay. The present multicenter pilot study was undertaken to evaluate current strategies in the treatment of shunt infection. Methods. Patients were enrolled in the study if they had a successful treatment of a CSF shunt infection proved by culture of a CSF specimen. Details of their care and the incidence of culture-proved reinfection were recorded. Seventy patients from 10 centers were followed up for 1 year after their CSF shunt infection. The initial management of the infection was shunt externalization in 17 patients, shunt removal and external ventricular drain insertion in 50, and antibiotic treatment alone in three. Reinfection occurred in 18 patients (26%). Twelve of the 18 reinfections were caused by the same organism and six were due to new organisms. The treatment time varied from 4 to 47 days, with a mean of 17.4 days for those who later experienced a reinfection compared with 16.2 days for those who did not. The most common organism (Staphylococcus epidermidis, 34 patients) was associated with a reinfection rate of 29% and a mean treatment time of 12.8 days for those who suffered reinfection and 12.5 days for those who did not. Conclusions. Reinfection after treatment of a CSF shunt infection is alarmingly common. According to the data available, the incidence of reinfection does not appear to be related to the duration of antibiotic therapy

Fracture characteristics of chem-tempered lenses

Fracture characteristics of chem-tempered lense

Agricultural Education Program Planning Handbook for Missouri Schools

The Program Planning Handbook for Missouri Schools is available in a PDF format as an introduction and 13 separate chapters.The Agricultural Education Program Planning Handbook for Missouri Schools was developed and written to provide guidance and assistance to agricultural educators in planning, conducting and evaluating programs of agriculture in Missouri's public schools. Since the last edition (1997) of the Handbook, several changes have taken place in how programs of agricultural education are planned, delivered, and evaluated. Therefore, the Joint Staff in Agricultural Education recommend that the Handbook be revised and re-distributed to Missouri's teachers of agriculture

Design and operating criteria for rural water systems

Rural homesites in the United States require the availability of high quality water. One means of meeting this need is with the rural water district, a system composed of tank storage and a pipe network serving a number of homes. The tanks are filled by pumping during periods of minimal water use and serve as the immediate water source for homes. Optimum design requires consideration of not only immediate needs and economic factors but also the possibility of expansion at some future date. Accurate prediction of monthly usage rates is sometimes necessary to set contractural needs. Daily water use per person must be known to appropriately choose the size of the storage tank. Peak use rates are important for proper selection of pipe sizes. The temporal distribution of demand is important in determining available pump operation periods for filling of storage with a minimum of interference and has a bearing on pump and pipe selection. This paper presents the results of a study (Goodwin, 1975) describing design criteria for projects serving dairies and domiciles. Homes are divided into two different economic groups and design recommendations are made for each group

Fastener starter tool

A fastener starter tool includes a number of spring retention fingers for retaining a small part, or combination of parts. The tool has an inner housing, which holds the spring retention fingers, a hand grip, and an outer housing configured to slide over the inner housing and the spring retention fingers toward and away from the hand grip, exposing and opening, or respectively, covering and closing, the spring retention fingers. By sliding the outer housing toward (away from) the hand grip, a part can be released from (retained by) the tool. The tool may include replaceable inserts, for retaining parts, such as screws, and configured to limit the torque applied to the part, to prevent cross threading. The inner housing has means to transfer torque from the hand grip to the insert. The tool may include replaceable bits, the inner housing having means for transferring torque to the replaceable bit

Analysis of Neighbourhoods in Multi-layered Dynamic Social Networks

Social networks existing among employees, customers or users of various IT systems have become one of the research areas of growing importance. A social network consists of nodes - social entities and edges linking pairs of nodes. In regular, one-layered social networks, two nodes - i.e. people are connected with a single edge whereas in the multi-layered social networks, there may be many links of different types for a pair of nodes. Nowadays data about people and their interactions, which exists in all social media, provides information about many different types of relationships within one network. Analysing this data one can obtain knowledge not only about the structure and characteristics of the network but also gain understanding about semantic of human relations. Are they direct or not? Do people tend to sustain single or multiple relations with a given person? What types of communication is the most important for them? Answers to these and more questions enable us to draw conclusions about semantic of human interactions. Unfortunately, most of the methods used for social network analysis (SNA) may be applied only to one-layered social networks. Thus, some new structural measures for multi-layered social networks are proposed in the paper, in particular: cross-layer clustering coefficient, cross-layer degree centrality and various versions of multi-layered degree centralities. Authors also investigated the dynamics of multi-layered neighbourhood for five different layers within the social network. The evaluation of the presented concepts on the real-world dataset is presented. The measures proposed in the paper may directly be used to various methods for collective classification, in which nodes are assigned to labels according to their structural input features.Comment: 16 pages, International Journal of Computational Intelligence System

Activation of epiplexus macrophages in hydrocephalus caused by subarachnoid hemorrhage and thrombin

AimsWe have found that hydrocephalus development in spontaneously hypertensive rats was associated with activation of epiplexus cells. The current study examined whether epiplexus cell activation occurs in a rat subarachnoid hemorrhage (SAH), whether activation would be greater in a subset of rats that developed hydrocephalus and the potential role of thrombin in epiplexus cell activation.MethodsThere were two parts in this study. First, an endovascular perforation was performed in rats to induce SAH. Second, rats received an intraventricular infusion of either thrombin or saline. Magnetic resonance imaging was used to measure the ventricular volumes. Immunofluorescence and immunohistochemistry were used to study epiplexus cell activation.ResultsIba‐1, OX‐6, and CD68 were expressed in the epiplexus cells of the choroid plexus in sham‐operated rats. SAH increased Iba‐1 and CD68 immunoreactivity in epiplexus cells in addition to an increase in Iba‐1‐positive cell soma size. Those effects were greater in rats that developed hydrocephalus. Intraventricular thrombin mimicked the effects of SAH on epiplexus cell activation and hydrocephalus.ConclusionThis study supports the concept that epiplexus cell activation is associated with hydrocephalus development. Epiplexus cell activation may be in response to thrombin production after hemorrhage, and it may be a therapeutic target.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151813/1/cns13203_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151813/2/cns13203.pd