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Ketamine has a number of clinical uses and properties that suggest a role for the drug in neuroanestheisa practice. “Dogma” and “myths” persist with regard to its effects on cerebral hemodynamics and intracranial pressure which have limited its use in Neuroanesthesia and care of the critically ill brain-injured patient. This review aims to educate the clinician on the possible role of ketamine in modern neuroanesthesia practice. A number of systemic reviews support the use of ketamine in patients with acute brain injury and raised intracranial pressure (ICP). Pre-clinical work suggests that ketamine may have mechanisms of action compatible with neuroprotection including modifying glutamate excitatory-driven mechanisms of brain injury. There is emerging clinical evidence to suggest that ketamine may inhibit spreading depolarizations (SDs), a cortical electrical phenomenon associated with brain injury. Ketamine is no longer contraindicated in the care of the brain-injured patient, and its properties of potent analgesia, dissociative anesthesia, and minimal effects on both the hemodynamic and respiratory system are being utilized in the pre-hospital and emergency room setting. Good grade data on meaningful clinical outcomes is presently lacking to support the use of ketamine as a drug with neuroprotection properties but is an area of ongoing interest.

STUDY DESIGN The enhanced perioperative care (EPOC) program is an institutional quality improvement initiative. We used a historically controlled study design to evaluate patients who underwent major spine surgery before and after the implementation of the EPOC program. OBJECTIVE To determine whether multidisciplinary EPOC program was associated with an improvement in clinical and financial outcomes for elective adult major spine surgery patients. SUMMARY OF BACKGROUND DATA The enhanced recovery after surgery (ERAS) programs successfully implemented in hip and knee replacement surgeries, and improved clinical outcomes and patient satisfaction. METHODS We compared 183 subjects in traditional care (TRDC) group to 267 intervention period (EPOC) in a single academic quaternary spine surgery referral center. One hundred eight subjects in no pathway (NOPW) care group was also examined to exclude if the observed changes between the EPOC and TRDC groups might be due to concurrent changes in practice or population over the same time period. Our primary outcome variables were hospital and intensive care unit lengths of stay and the secondary outcomes were postoperative complications, 30-day hospital readmission and cost. RESULTS In this highly complex patient population, we observed a reduction in mean hospital length of stay (HLOS) between TRDC versus EPOC groups (8.2 vs. 6.1 d, standard deviation [SD] = 6.3 vs. 3.6, P

This chapter discusses the common cerebrovascular disorders that present for surgical intervention, which include intracranial aneurysms, vascular malformations (arteriovenous malformation, dural arteriovenous fistula, cavernoma), occlusive cerebrovascular diseases (moyamoya, atherosclerotic vascular occlusion), and cranial vascular compression syndromes (trigeminal neuralgia, hemifacial spasm). It covers the critical goals of peri-operative management of cerebrovascular surgery, including maintenance of adequate cerebral perfusion, optimization of haemodynamic and ventilation parameters to avoid cerebral ischaemia and hyperaemia, creation of favourable surgical conditions, and facilitation of intra-operative neurophysiological monitoring and brain protection. Anaesthetic management of cerebrovascular surgery involves integrating the implications of intracranial as well as extracranial manifestations of the neurological pathology with the principles of anaesthetic neuropharmacology in the context of planned surgical procedure and neuromonitoring. Careful pre-operative evaluation, selection of suitable anaesthetic agents and monitors, and preparedness to deal with potential complications are the key to successful outcome of cerebrovascular surgery.

Migratory salmon move nutrients both in and out of fresh waters during the different parts of their life cycle. We used a mass-balance approach to quantify recent changes in phosphorus (P) fluxes in six coastal California, USA, watersheds that have recently experienced dramatic decreases in salmon populations. As adults, semelparous Chinook ( Oncorhynchus tshawytscha ) and coho ( Oncorhynchus kisutch ) salmon imported 8.3 and 10.4 times more P from the ocean, respectively, than they exported as smolts, while iteroparous steelhead (i.e., sea-run rainbow trout, Oncorhynchus mykiss ) imported only 1.6 times more than they exported as kelts and smolts. Semelparous species whose life histories led them to import more nutrients were also the species whose populations decreased the most dramatically in California in recent years. In addition, the relationship between import and export was nonlinear, with export being proportionally more important at lower levels of import. This pattern was driven by two density-dependent processes — smolts were larger and disproportionately more abundant at lower spawner abundances. In fact, in four of our six streams we found evidence that salmon can drive net export of P at low abundance, evidence for the reversal of the “conveyor belt” of nutrients.

Background Transient adenosine-induced asystole is a reliable method for producing a short period of relative hypotension during surgical and endovascular procedures. Although the technique has been described in the endovascular treatment of brain arteriovenous malformations, aortic aneurysms, and posterior circulation cerebral aneurysms, little description of its use in anterior circulation aneurysms is available. Objective To assess the benefits of adenosine-induced transient asystole in complex anterior circulation aneurysms, to describe our experience in selected cases, and to provide the first experience of the use of adenosine in anterior circulation aneurysms. Methods The adenosine-induced cardiac arrest protocol allows us to titrate the duration of cardiac arrest on the basis of individual patient responses. The operative setup is the same as with all aneurysm clippings, with the addition of the placement of transcutaneous pacemakers as a precaution for prolonged bradycardia or asystole. Escalating doses of adenosine are given to determine the approximate dose that results in 30 seconds of asystole. When requested by the surgeon, the dose of adenosine is administered for definitive dissection and clipping. We present 6 cases in which this technique was used. Results The use of transient adenosine-induced asystole provided excellent circumferential visualization of the aneurysm neck and safe clip application. All patients did well neurologically and suffered no evidence of perioperative cerebral ischemia or delayed complication from the use of adenosine itself. Conclusion Transient adenosine-induced asystole is a safe and effective technique in select circumstances that may aid in safe and effective aneurysm clipping. Along with the traditional techniques of brain relaxation, skull base approaches, and temporary clipping, adenosine-induced asystole facilitates circumferential visualization of the aneurysm neck and is another technique available to cerebrovascular surgeons.

PURPOSE OF REVIEW To present current knowledge about the metabolic management of patients undergoing solid organ transplantation, and potential organ donors. RECENT FINDINGS Appropriate management of electrolytes and glucose improves outcome after transplantation, although conflicting evidence exists. Patients with cirrhosis-induced hyponatremia can be successfully transplanted but are at increased risk of postoperative complications. A new class of drugs, the vaptans, that antagonizes arginine vasopressin may be an effective treatment for hyponatremia in transplant candidates. Recent literature has documented the implications, predictors and potential therapies for perioperative hyperkalemia in the transplant population. The debate over appropriate targets for serum glucose in perioperative and critically ill patients has been lively. The documented risk of hypoglycemia associated with 'intensive insulin therapy' has led to the adoption of more conservative glycemic targets. Studies of glycemic control in transplant recipients are limited. SUMMARY In patients undergoing solid organ transplants, sodium management should aim to minimize an acute change in sodium concentration. Vaptans may be of future use in optimizing patients with cirrhosis prior to transplantation. Pending further studies, a perioperative 'middle ground' target glucose of between 140 and 180 mg/dl seems reasonable at this time.

Soil properties and stable carbon isotope ratios contained in the soil organic matter (SOM) were used to investigate the change in vegetative history of land cleared anciently for maize (Zea mays L.) agriculture in the Petexbatun region of Guatemala. Maize and other C4 plants associated with land clearance leave a carbon isotopic signature in the SOM different from the C3 plants of native forest vegetation. Soil profiles were collected from various landscape features around the Classic Maya site of Aguateca: control locations (areas likely not used in ancient agriculture), defensible locations (areas near defensive walls), rejolladas (natural karst depressions), upland locations (well-drained soils atop the Aguateca escarpment), and bajos (seasonal and perennial wetlands). The chemical and physical properties of the profiles were examined and the soils were taxonomically classified to the great group level. The changes in d13C with soil depth were determined and compared statistically. The 13C enrichment of the SOM in bajo and rejollada profiles were similar and were significantly (p < 0.05) greater than the control, defensible, and upland soils. This isotopic signature of sustained C4 vegetation was likely associated with forest clearance and ancient Maya agriculture. Both the bajo and rejollada landscape features appear to have been valuable agricultural resources for ancient Maya. © 2009 Wiley Periodicals, Inc.

I make no apology for returning to the theme of the world map – the vital, crucial object that encompasses all our geographical endeavours (Wright, 2003). For, despite all the wonders of computers,...

Market economies are notoriously difficult to identify in the archeological record. This is particularly true in the subtropical Maya lowlands of Mexico, Guatemala, and Belize because most utilitarian items and consumables were made of highly perishable materials. We explore the hypothesis that ancient marketplaces can be identified through analysis of chemical residues in soils from open and easily accessible spaces in and about ancient Maya cities. We compared soil chemical signatures from a credible ancient marketplace location in the specialized trade center of Chunchucmil, Yucatan, Mexico to those from a modern marketplace at Antigua, Guatemala. We found extraordinarily high concentrations of phosphorus and zinc in the soil of Chunchucmil's proposed marketplace and the same high concentrations correlate well with food preparation and vegetable sales areas at the modern marketplace. These methods hold promise in resolving the vexing question of how large ancient Maya urban populations were sustained.

The ancient Maya subsisted in an environment limited by shallow soils and unpredictable weather patterns until their collapse ∼A.D. 800–900. Ancient subsistence can be a difficult subject, with little physical evidence of agricultural artifacts and structures. This study characterized soil profiles and utilized changes in stable carbon isotope ratios of soil organic matter (SOM) to locate and interpret areas of ancient C4 plant growth and maize (Zea mays) cultivation among the Maya. The investigation indicated some of the challenges the Maya faced, including shallow and sloped soils in some areas. The C4 plant signature was found in seasonal wetland soils on the opposite side of the Laguneta Aguateca from the ruins of Aguateca, but not in the perennial wetlands on the immediate side. No C4 plant signature was detected in the shoulder and backslope soils. Based on these findings, the ancient Maya of Aguateca probably adapted to their environment by farming rich toeslope soils. It is possible that maize was also grown in the seasonal wetlands adjacent to the site. If the steep backslope soils around Aguateca were used in ancient agriculture, the evidence has probably eroded away. © 2007 Wiley Periodicals, Inc.

Excessive blood sampling, with its inherent risks, is of growing concern among clinicians. We performed this study to measure the changes in hematocrit (Hct) during a laboratory investigation where multiple blood samples are collected. The performance of a simple mathematical model, used in clinical practice to predict Hct changes, is evaluated. Eight healthy male volunteers participated in this study. The equation Hctf = Hcti*(EBV-BL)/EBV is used to predict changes in Hct. Where Hctf and Hcti are, respectively, the final and initial Hct, EBV is the estimated blood volume and BL is the blood loss. Thirty-five pharmacokinetic samples per subject were collected totalling 314 mL of BL. The Hct decreased from 44.2% ± 2.2% to 39.9% ± 2.5% (P = 0.001). On average, model predictions tended to have a discrete tendency to underestimate the Hct changes (-0.5% points of bias). While the predictions of the Hct were very accurate in 50% of the subjects, the discrepancy of the Hct predictions was clinically significant in the other 50% of the subjects. Consistent with the model prediction, this study demonstrated a significant reduction in the Hct values in healthy subjects undergoing incremental phlebotomy. On average, the model successfully predicted the decrease in Hct. However, the inter- and intra-individual variabilities in the Hct changes are clinically significant. In clinical settings, which are not well controlled environments, the variability is likely to be greater and the clinical use of the model cannot replace the need to monitor the Hct. Les echantillons sanguins excessifs, et leurs risques inherents, preoccupent de plus en plus les cliniciens. Nous avons mesure les modifications de l’hematocrite (Hct) au cours d’une investigation en laboratoire ou de multiples echantillons sanguins sont preleves. La performance d’un modele mathematique simple, qui predit les changements de l’Hct en clinique, est evaluee. Huit hommes volontaires en sante ont participe a l’etude. L’equation Hctf = Hct*(VSE-PS)/VSE sert a predire les changements de l’Hct ou Hct et Hct sont respectivement l’Hct final et initial, VSE est le volume sanguin estime et PS est la perte sanguine. Trente-cinq echantillons pharmacocinetiques par sujet ont ete preleves pour un total de 314 mL de PS. L’Hct a diminue de 44,2 % ± 2,2 % a 39,9 % ± 2,5 % (P = 0,001). Les predictions du modele presentaient en moyenne une tendance discrete a sous-estimer les modifications de l’Hct (-0,5 % de biais). Les predictions de l’Hct ont ete tres exactes chez 50 % des sujets, mais la divergence dans les predictions etait cliniquement significative chez les autres 50 %. L’etude a demontre, conformement au modele de prediction, une reduction significative des valeurs de l’Hct chez des sujets sains qui subissent une phlebotomie incrementielle. En moyenne, le modele a pu predire la baisse de l’Hct. Cependant, les variations interindividuelles et intra-individuelles de modification de l’Hct sont cliniquement significatives. En clinique, ce qui n’est pas un environnement bien contrale, la variabilite risque d’etre plus grande et l’usage clinique du modele ne peut remplacer la necessite du moniteur d’Hct.

Background Dexmedetomidine, a highly selective alpha2-adrenoceptor agonist used for short-term sedation of mechanically ventilated patients, has minimal effect on ventilation. Methods This study compared the respiratory effect of dexmedetomidine to that of remifentanil. The authors measured and compared respiratory responses of six healthy male volunteers during (1) a stepwise target-controlled infusion of remifentanil, (2) a stepwise target-controlled infusion of dexmedetomidine, and (3) a pseudonatural sleep session. Results Compared with baseline, remifentanil infusions resulted in respiratory depression as evidenced by a decrease in respiratory rate and minute ventilation, respiratory acidosis, and apnea episodes resulting in desaturations. Remifentanil disturbed the natural pattern of breathing and flattened the distribution of ventilatory timing (inspiratory time/ventilatory cycle time). The respiratory effects of dexmedetomidine markedly contrasted with those of remifentanil. When compared with baseline, during dexmedetomidine infusions, the respiratory rate significantly increased, and the overall apnea/hypopnea index significantly decreased. The distribution of inspiratory time/ventilatory cycle time showed an increased peak. In addition, dexmedetomidine seemed to mimic some aspect of natural sleep. While the subjects were breathing a 5% CO2 mixture, hypercapnic arousal phenomena (documented by the Bispectral Index, the electroencephalogram, and sudden increase in the minute ventilation) were observed during dexmedetomidine infusions. Similar phenomena during natural sleep have been reported in the literature. Conclusions In comparison with remifentanil, dexmedetomidine infusions (1) did not result in clinically significant respiratory depression, (2) decreased rather than increased the apnea/hypopnea index, and (3) exhibited some similarity with natural sleep.

Background Dexmedetomidine is a highly selective alpha2-adrenoceptor agonist used for short-term sedation of mechanically ventilated patients. The analgesic profile of dexmedetomidine has not been fully characterized in humans. Methods This study was designed to compare the analgesic responses of six healthy male volunteers during stepwise target-controlled infusions of remifentanil and dexmedetomidine. A computer-controlled thermode was used to deliver painful heat stimuli to the volar side of the forearms of the subjects. Six sequential 5-s stimuli (ranging from 41 degrees to 50 degrees C) were delivered in random order. The recorded visual analog scale was used to fit an Emax model. Results Compared to baseline, remifentanil infusions resulted in a right shift of the sigmoid curve (increased T50, the temperature producing a visual analog scale score of 50% of the maximal effect, from 46.1 degrees C at baseline to 48.4 degrees and 49.1 degrees C during remifentanil infusions) without a change of the steepness of the curve (identical Hill coefficients gamma during baseline and remifentanil). Compared to baseline, dexmedetomidine infusions resulted in both a right shift of the sigmoid curve (increased T50 to 47.2 degrees C) and a decrease in the steepness of the curve (decreased gamma from 3.24 during baseline and remifentanil infusions to 2.45 during dexmedetomidine infusions). There was no difference in the pain responses between baseline and after recovery from remifentanil infusions (identical T50 and gamma). Conclusion As expected, dexmedetomidine is not as effective an analgesic as the opioid remifentanil. The difference in the quality of the analgesia with remifentanil may be a reflection of a different mechanism of action or a consequence of the sedative effect of dexmedetomidine.

The increase in maintenance of software and the increased amounts of reuse are having major positive impacts on the quality of software, but are also introducing some rather subtle negative impacts on the quality. Instead of talking about existing problems (faults), developers now discuss “potential problems,” that is, aspects of the program that do not affect the quality initially, but could have deleterious consequences when the software goes through some maintenance or reuse. One type of potential problem is that of common coupling, which unlike other types of coupling can be clandestine. That is, the number of instances of common coupling between a module M and the other modules can be changed without any explicit change to M. This paper presents results from a study of clandestine common coupling in 391 versions of Linux. Specifically, the common coupling between each of 5332 kernel modules and the rest of the product as a whole was measured. In more than half of the new versions, a change in common coupling was observed, even though none of the modules themselves was changed. In most cases where this clandestine common coupling was observed, the number of instances of common coupling increased. These results provide yet another reason for discouraging the use of common coupling in software products.

We present a case of tongue necrosis due to intraoperative pressure injury. A laryngeal mask airway with adhesive electrodes was inserted into the oropharynx, over an endotracheal tube, to facilitate glossopharyngeal nerve monitoring during craniotomy for a cerebellopontine angle tumor. The case, mechanisms of injury, and modifications to our current practice are discussed.

Communication skills, including reading, writing, speaking, and teaming, are among the most sought after by employers of recent Computer Science/Software Engineering (CS/SE) graduates. We have been conducting a project that has developed a general framework for program-level integration of communication into CS/SE education. Our framework has been developed through workshops and field evaluation of training materials (and other resources) by faculty from a wide variety of institutions under the guidance of experts in writing and communication across the curriculum. This paper discusses the current state of communication teaching in the CS/SE domain, and presents our framework and experiences for program-wide implementation of communication skills.

BRIEF SUMMARY: We describe the use of adenosine-induced cardiac arrest to facilitate intracranial aneurysm clip ligation.Cerebral aneurysms are highly variable which may result in difficult surgical exposure for clip ligation in select cases. Secure clip placement is often not feasible without temporarily decompressing the aneurysm. This can be accomplished with temporary clip ligation of proximal vessels, or with deep hypothermic circulatory arrest on cardiopulmonary bypass, although these methods have their own inherent risks. Here we describe an alternate method of decompressing the aneurysm via adenosine-induced transient asystole.We examined the records of 27 patients who underwent craniotomy for cerebral aneurysm clipping in which adenosine was used to induce transient asystole to facilitate clip ligation. Duration of adenosine-induced bradycardia (heart rate40) and hypotension (SBP60) recorded on the electronic anesthesia record and outcome data including incidence of successful clipping, intraoperative and postoperative complications, and mortality were recorded.Satisfactory aneurysm decompression was achieved in all cases, and all aneurysms were clipped successfully. The median dose of intravenous adenosine resulting in bradycardia greater than 30 seconds was 30 mg. The median dose of adenosine resulting in hypotension greater than 30 seconds was 15 mg, and greater than 60 seconds was 30 mg. One case of prolonged hypotension after rapid redosing of adenosine required brief closed chest compressions before circulation was spontaneously restored. No other adverse events were observed.Adenosine cardiac arrest is a relatively novel method for decompression of intracranial aneurysms to facilitate clip application. With appropriate safety precautions, it is a reasonable alternative method when temporary clipping of proximal vessels is not desirable or not possible.

Objective Neurophysiological intraoperative monitoring of the glossopharyngeal nerve has been performed only with needle electrodes inserted into the pharyngeal muscles or soft palate. We describe a noninvasive method of monitoring this cranial nerve. Methods A 30-year-old man who presented with headache, as well as speech and swallowing difficulty, underwent surgical resection of a right vagus nerve schwannoma. Neurophysiological intraoperative monitoring of multiple lower cranial nerves, including the glossopharyngeal and vagus nerves, was performed. Results The glossopharyngeal nerve was monitored with an adhesive surface electrode mounted on the cuff of a laryngeal mask airway, and the vagus nerve was monitored with a similar electrode mounted on the endotracheal tube. Successful monitoring allowed separation of the glossopharyngeal nerve from the tumor, and there was no postoperative swallowing deficit. Conclusion Monitoring of the glossopharyngeal nerve with surface electrodes is possible and reliable, but it must be combined with vagus nerve monitoring.

The ethical conduct of research is a cornerstone of modern scientific research. Computer science and the discipline's technological artifacts touch nearly every aspect of modern life, and computer scientists must conduct and report their research in an ethical manner. This workshop will identify four theories that offer guidance for ethical decision making, ad use these theories as a basis for evaluating and discussing a set of ethical dilemmas that researchers in computer science might face.

Code reuse has been a fundamental principle of software engineering for decades, with modules and libraries of both general purpose and highly specialized code serving as the discipline's equivalent of bricks and steel. Research and practice have resulted in extensive general-purpose libraries incorporated into production level compilers, as well as a wide variety of special-purpose libraries and programming toolkits. While reusable code has helped make software more reliable and simplified some details of implementation, developing software systems that meet customer expectations on time and within budget remains problematic.

Excessive blood sampling, with its inherent risks, is of growing concern among clinicians. We performed this study to measure the changes in hematocrit (Hct) during a laboratory investigation where multiple blood samples are collected. The performance of a simple mathematical model, used in clinical practice to predict Hct changes, is evaluated.Eight healthy male volunteers participated in this study. The equation Hct(f) = Hct(i)*(EBV-BL)/EBV is used to predict changes in Hct. Where Hct(f) and Hct(i) are, respectively, the final and initial Hct, EBV is the estimated blood volume and BL is the blood loss.Thirty-five pharmacokinetic samples per subject were collected totalling 314 mL of BL. The Hct decreased from 44.2% +/- 2.2% to 39.9% +/- 2.5% (P = 0.001). On average, model predictions tended to have a discrete tendency to underestimate the Hct changes (-0.5% points of bias). While the predictions of the Hct were very accurate in 50% of the subjects, the discrepancy of the Hct predictions was clinically significant in the other 50% of the subjects.Consistent with the model prediction, this study demonstrated a significant reduction in the Hct values in healthy subjects undergoing incremental phlebotomy. On average, the model successfully predicted the decrease in Hct. However, the inter- and intra-individual variabilities in the Hct changes are clinically significant. In clinical settings, which are not well controlled environments, the variability is likely to be greater and the clinical use of the model cannot replace the need to monitor the Hct.

Pulse oximeters may delay displaying the correct oxygen saturation during the onset of hypoxia. We investigated the desaturation response times of pulse oximeter sensors (forehead, ear and finger) during vasoconstriction due to mild hypothermia and vasodilation caused by glyceryl trinitrate. Ten healthy male volunteers were given three hypoxic challenges of 3 min duration under differing experimental conditions. Mild hypothermia increased the mean response time of finger oximeters from 130 to 215 s. Glyceryl trinitrate partly offset this effect by reducing the response time from 215 to 187 s. In contrast, the response times of the forehead and ear oximeters were unaffected by mild hypothermia, but the difference between head and finger oximeters was highly significant (p < 0.0001). The results suggest that the head oximeters provide a better monitoring site for pulse oximeters during mild hypothermia.

Dexmedetomidine, a highly selective alpha2-adrenoceptor agonist used for short-term sedation of mechanically ventilated patients, has minimal effect on ventilation.This study compared the respiratory effect of dexmedetomidine to that of remifentanil. The authors measured and compared respiratory responses of six healthy male volunteers during (1) a stepwise target-controlled infusion of remifentanil, (2) a stepwise target-controlled infusion of dexmedetomidine, and (3) a pseudonatural sleep session.Compared with baseline, remifentanil infusions resulted in respiratory depression as evidenced by a decrease in respiratory rate and minute ventilation, respiratory acidosis, and apnea episodes resulting in desaturations. Remifentanil disturbed the natural pattern of breathing and flattened the distribution of ventilatory timing (inspiratory time/ventilatory cycle time). The respiratory effects of dexmedetomidine markedly contrasted with those of remifentanil. When compared with baseline, during dexmedetomidine infusions, the respiratory rate significantly increased, and the overall apnea/hypopnea index significantly decreased. The distribution of inspiratory time/ventilatory cycle time showed an increased peak. In addition, dexmedetomidine seemed to mimic some aspect of natural sleep. While the subjects were breathing a 5% CO2 mixture, hypercapnic arousal phenomena (documented by the Bispectral Index, the electroencephalogram, and sudden increase in the minute ventilation) were observed during dexmedetomidine infusions. Similar phenomena during natural sleep have been reported in the literature.In comparison with remifentanil, dexmedetomidine infusions (1) did not result in clinically significant respiratory depression, (2) decreased rather than increased the apnea/hypopnea index, and (3) exhibited some similarity with natural sleep.

NC State University (NCSU) is embarked on an ambitious vision to change the paradigm for higher education and research by ‘virtualising’ its award-winning Centennial Campus (creating so called vCentennial). Centennial Campus is a small city made up of NCSU research, teaching and outreach facilities, entrepreneurs, academic entities, private firms, and government agencies. NCSU wants the ability to replicate services and functionality of this physical environment and its virtual avatars ‘anywhere, anytime’ in the world using a cloud of clouds computing platform. The initial operating system for this platform is NCSU’s open source Virtual Computing Laboratory (VCL) technology. This paper provides an overview of the vision and discusses several vCentennial pilot projects.

On both sides of the Atlantic, there is serious concern that children do not know where places are. Many surveys show the extent of this ignorance. The media blame the teachers. Sometimes the cause of this ignorance is alleged to be the lack of geography coursework. Sometimes, more ominously, geography teachers themselves are blamed. Sometimes it is the “wrong sort of geography” that is blamed; it is claimed that pupils learn about shops and houses and do not learn about the world.

The subject of project peer review of structural design was a major topic of discussion at both the 1983 Santa Barbara Engineering Foundation conference, Building Structural Failures—Their Cause and Prevention, and the 1987 follow‐up conference in Palm Coast, Florida, Structural Failures II. The deliberations of the Palm Coast conference regarding project peer review, which are the subject of this paper, resulted in the very significant recommendation that peer review of projects over a certain threshold level be made mandatory through incorporation into code provisions or by requirements of regulating authorities, and that the cost of such reviews should be borne by the owner. Several questions remain regarding the criteria and procedures of such a review, such as the threshold limits for projects that should be subject to review, the scope of the review, the liability of the reviewer, and the timing of the review. A joint committee of the ASCE and the American Consulting Engineers Council (ACEC) is work...

A flow-through system using plexiglass "microbasins" was used to study methyl mercury release from unpolluted, mercury polluted, and mercury enriched lake and river sediments. Production of methyl mercury ranged up to 3.3 μg∙m−2∙d−1, increasing with increasing mercury content as if following saturation kinetics. It leveled off when mercury content was 15–20 μg Hg/g. An equilibrium between methylating and demethylating mechanisms is suggested. Release at 4 °C was 50–70% of that at 20 °C, which suggests that in polluted Canadian lakes, production in winter may be half the total for the year. Increased methyl mercury release was observed when tryptic soy broth (TSB) was added to sediments at 0.06 or 0.25 g/dm3, and very marked increases when TSB was added to the water flow at 35 mg/L, suggesting an effect at the sediment–water interface.Key words: mercury, methyl mercury, methylation, microbasin, microorganism, sediments, biomethylation