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This paper reports on the experience of using the EDURange framework, a cloud-based resource for hosting on-demand interactive cybersecurity scenarios. Our framework is designed especially for the needs of teaching faculty. The scenarios we have implemented each are designed specifically to nurture the development of analysis skills in students as a complement to both theoretical security concepts and specific software tools.Our infrastructure has two features that make it unique compared to other cybersecurity educational frameworks. First, EDURange is scalable because it is hosted on a commercial, large-scale cloud environment. Second, EDURange supplies instructors with the ability to dynamically change the parameters and characteristics of exercises so they can be replayed and adapted to multiple classes. Our framework has been used successfully in classes and workshops for students and faculty. We present our experiences building the system, testing it, and using feedback from surveys to improve the system and boost user interest.

Civil engineers are increasingly adopting computer and communications systems to conduct business. Engineering relies on computer-aided design, simulation, project management software, electronic funds transfers, automated control processes, satellite communications, geographic information systems, electronic mail, and digital records. The transformation of engineering by information technology holds out much promise in revolutionizing the way engineers do business. However, the technological progress also introduces vulnerabilities that threaten engineering enterprises. Aside from the touted Y2K threats, competitors, criminals, and disgruntled employees threaten the computerized information systems. This paper examines the role of civil engineers in this contemporary information age by identifying trends in the use of computer and communications systems, examining vulnerabilities of these systems, and providing insights for protection. To be truly effective, information defense must begin at the root level in each engineering organization.

Training has become a growth industry during the 1980s and 1990s. A 1995 survey of U.S. industries with 100 or more employees reported that approximately $52 billion was spent annually on training employees, while total costs for all companies are estimated at $90 to $100 billion. As technology evolves, some experts in the architectural, engineering, and construction (AEC) industries predict that training costs will grow five-fold from current levels. Who is receiving all of this training, and why? How is training being conducted; and are there better ways to do it? Are there cost-effective ways to conduct training? These issues are critical if the AEC industry is to remain responsive and competitive in rapidly changing national and global markets. This paper surveys recent training trends, and insights are offered about how and why the AEC industry trains employees. Considering recent technological innovations, new ideas are presented for how training could be conducted to exploit technology and deliver ...

The presence of positive acute phase proteins within the circulation of rheumatoid arthritis patients suggests that elevated cytokine production associated with this chronic inflammatory disorder initiates the hepatic acute phase response. Cytokines produced at inflammatory lesions are believed to travel via the circulation to the liver where they induce acute phase protein production by hepatocytes. To test whether serum from rheumatoid arthritis patients contained sufficient levels of cytokines to promote an acute phase response in vitro, a bioassay was developed that employed the human hepatoma cell line Hep3B. These cells produced the acute phase protein serum amyloid A (SAA) in response to a combination of recombinant IL-1 beta and IL-6 or to monocyte conditioned medium. Serum (or plasma) from normal individuals or from rheumatoid arthritis patients did not induce SAA production by Hep3B cells. Moreover, these serum samples did not prevent SAA production induced by monocyte conditioned medium, indicating that they did not contain inhibitors of cytokine activity. Despite the inactivity of serum samples, synovial fluid samples obtained from rheumatoid arthritis patients were active in the hepatocyte bioassay and promoted SAA synthesis. One synovial fluid sample was analysed in detail to identify cytokines responsible for the SAA-inducing activity. Neutralizing antisera against IL-6 and IL-1 beta blocked this activity by > 90% whereas anti-IL1 alpha and anti-TNF-alpha sera were without effect. Absolute cytokine levels within the synovial fluid sample were determined by ELISA; IL-6, IL-beta and TNF-alpha, but not IL-1 alpha, were confirmed to be present. Moreover, the synovial fluid sample contained a large amount of the IL-1 receptor antagonist. These data indicate, therefore, that synovial fluid recovered from an inflamed joint contains all the necessary cytokines in balance with inhibitors to promote SAA production by Hep3B cells. The steady state levels of these factors within the plasma compartment, however, were insufficient to induce the acute phase response by cultured Hep3B cells, suggesting that this system does not mimic the relationship between the circulation and the liver that likely exists in rheumatoid arthritis patients.

To the Editor. —Of the first 15 persons referred to our center for a therapeutic recombinant gp120 vaccine trial, two were in fact not infected with the human immunodeficiency virus (HIV). Undocumented patient reports of a positive test for HIV infection must be confirmed prior to therapeutic interventions, especially if patients lack clinical manifestations of HIV disease. Report of Cases.—Case 1. —A 35-year-old heterosexual man contracted genital herpes simplex following vaginal intercourse with a prostitute. Three weeks later, he was tested for HIV at an anonymous testing center and told he was positive. Despondent, he did not return for results of a repeat test. Over 3 years, he sold most of his possessions, avoided dating, abstained from intercourse, ceased seeking to advance his career, and significantly increased his use of ethanol. The patient had a CD4 cell count of 0.87×10 9 /L (869/μL) on two occasions. He declined

The total protein and trace element content in various tissues from 1, 2, 4, 8, 16, 32, 64, and 128 day-old rats were determined. Protein content in heart, skin and hair continued to increase as a function of age whereas liver, kidney and lung protein content showed no change after the weaning period. The protein content in all tissues tested decreased sharply to minimum values at 2 to 4 days of age before increasing to constant levels.

Zinc deficiency is associated with poor growth and development. It has been postulated that a deficiency of the various zinc metalloenzymes results from the lack of dietary zinc. From present study, an examination of some aspects of this postulate, we conclude the following about zinc deficiency in pigs: (1) Of the tissues studied, it results in diminished zinc content only in liver, kidney, and pancreas. (2) It is associated with tissue ab normalities of various trace elements other than zinc. (3) Histochemical enzyme assays are satisfactory for qualitative but not quantitative determination of zinc me talloenzymes. (4) Deficiency of various tissue zinc metalloenzymes is difficult to demonstrate, even in severezinc deficiency. (5) It is associated with decreased activity of hepatic leucine aminopeptidase and ornithine transcarbamylase, and decreased serum cholesterol concentrations. Our findings are consistent with the postulate that alterations in a number of trace elements may occur in the entity called zinc deficiency.

Advances in knowledge of the trace elements zinc, manganese, and copper are reviewed (151 references), particularly as related to human metabolism and disorders. The literature reviewed, with few exceptions, is that published by December 1973.

The content of zinc, magnesium, calcium, bilirubin, and bile acids was determined in the hepatic bile of zinc-deficient and control swine. Zinc deficiency was produced by dietary zinc restriction while pair fed zinc supplemented animals served as controls for observations of hepatobiliary functions. Pigs weighing 5 kg were placed in two groups and fed the respective diets for 6 weeks; hair and skin abnormalities as well as decreased weight gain were present in the zinc-deficient group by this time. Hepatic bile and pancreatic juice were obtained from each animal after careful isolation and cannulation of the pancreatic and bile ducts. Animals were studied for a 3-hr period while under constant secretin stimulation and chloralose anesthesia. During this period, there was a progressive decrease in the biliary concentrations of bilirubin, bile acids, and magnesium in the bile of both groups, while zinc and calcium levels were not altered. The zinc concentrations in pancreatic juice were reduced in th...

Serum selenium as well as serum zinc, copper, magnesium, calcium and manganese were investigated in a control group of adult males and in 11 groups of patients in various disease states. Not only the change of each trace element but also the possible association between elements was studied in the various groups. All patients were fasting when sampled and studied only after the acute phase of the disease was corrected. Trace metal determinations were performed by atomic absorption spectrophometry (Mg, Ca, Cu, Zn) and by neutron activation analysis (Se, Mn). All patients showed low serum zinc when compared to controls. Cirrhotic patients had a low serum selenium level as well as low calcium, magnesium and zinc. Emphysemia and cancer patients had an elevated serum copper concentration while copper and manganese levels were elevated in congestive heart failure, infection and pschoses. To our knowledge this is the first time low serum selenium values have been demonstrated to be associated with the low serum zinc, calcium and magnesium levels found in cirrhotic patients.

The uncontrolled transmission of hog cholera in a large animal isolation facility, designed to control the movement of aerosols within and between individual wings of a multiunit building, indicated the need for a critical study of aerosol behavior under existing conditions of operation. Studies with aerosols of Escherichia coli B T3 bacteriophage (T3 coliphage) conclusively demonstrated the impossibility of obtaining the desired control by means of a “static” air balance relationship between adjacent areas within the facility. Modifications needed to provide the desired control of the air-handling system are outlined and discussed.

Alimentary triglyceridemia was induced in 20 normal male volunteers by ingestion of 100 g of peanut butter (triglyceride 50%) with 2 slices of bread and 2 cups of water or unsweetened coffee. By comparison of the postprandial triglyceride fatty acid pattern with that of the ingested fat and the fasting serum, the alimentary lipemia has been partitioned into its endogenous and exogenous triglyceride components. The mean increase in serum triglyceride at 4 hr after a fat meal was 130 mg/100 ml, 93 % of which was derived from the absorbed fat. The mean endogenous contribution rose slightly at the 4-hr point. However, subjects whose alimentary lipemia was more than double the fasting value invariably showed an increase in endogenous contribution, whereas those whose post-prandial value was less than twice fasting exhibited a decrease in endogenous lipemia. The increases of both endogenous and exogenous components seen with the greater lipemia elevations suggest saturation of a clearing mechanism. Add...

Summary Duodenal aspiration in seven normal subjects after secretin stimulation showed a mean secretion of 142 μg of zinc in 60 min with a range of 118 to 210,μg. Patients with chronic pancreatitis responded to secretin with lower total volumes, bicarbonate concentration and zinc content. Zinc concentration was also depressed. Cirrhotic patients excreted significantly less zinc than normal subjects although total volume of secretion was larger and the total bicarbonate excretion was within normal limits.

SummaryTypical pancreatic changes were induced by ethionine, which were not altered by addition of cortisone. The high incidence of gastric ulceration and hemorrhage found with ethionine alone was doubled in rats receiving cortisone also.

The distribution of 65 Zn among the serum proteins of 18 cirrhotic patients and 10 normal individuals was studied. Total zinc was measured in each serum. Zinc was bound to albumin, transferrin and α 2 -macroglobulin in all subjects. It was bound to IgG in all cirrhotics and five of ten normals. Utilizing the percentage distribution of 65 Zn and total serum zinc, the amount bound in each fraction was calculated. Albumin-bound zinc correlated well with total serum zinc (r = 0.97). Total serum zinc was lower in cirrhotics than in normals (p α 2 -macroglobulin. The total amount bound to these proteins (Tf- α 2 M) was of remarkably constant and equivalent size in normals and cirrhotics. Transferrin concentration was significantly lower (p α 2 -macroglobulin was higher in cirrhotics although the difference was not significant (p α 2 -macroglobulin. However, the total amount bound to Tf- α 2 M remains remarkably constant even when total serum zinc falls as low as 12 μg./ml. The constancy of the amount of zinc bound to Tf- α 2 M implies metabolic control of this fraction. When serum zinc falls to very low levels, it may account for nearly one-half of the total serum zinc. It is suggested that transferrin and α 2 -macroglobulin may have an important role in internal zinc exchange.

A procedure was developed for evaluating high-efficiency filters mounted in exhaust ducts at the National Animal Disease Laboratory. An aerosol of the test organism, Escherichia coli B T 3 bacteriophage, was generated in a chamber attached to a ceiling exhaust register in concentrations of at least 1000 viable organisms per ft 3 of air. Samples were collected from both the pre- and postfilter areas, and the number of organisms per ft 3 of air was determined. The efficiency of the filter was calculated from these figures. A total of 269 high-efficiency filters were tested. Of these, 249 had efficiencies of 98% or greater. The remaining 20, with efficiencies of less than 98%, were repaired and retested. No filter was accepted with an efficiency of less than 98%.

The knowledge of the relationship between protein metabolism and pancreatic function is as yet incomplete. Many excellent experimental, pathological and clinical investigations indicate that such a relationship exists.

NTEREST in the concentration of ammonia in the blood and its relation to neuropsychiatric disturbances has largely centered about liver disease. The identification of ammonia as the presumptive cause of the meat intoxication syndrome of Eck fistula dogs [I] has been followed by the repeated demonstration of abnormal blood ammonia levels in cirrhotic patients. Recent investigations indicating the presence of abnormal ammonia concentrations in nonhepatic diseases [2,3], as well as the importance of non-hepatic sources of ammonia [4], warrant a further consideration of the relation of ammonia to cerebral function. It was the purpose of this investigation to study the venous blood ammonia level in patients with Laennec’s cirrhosis and its various complications, including hepatic coma, and in patients with various nonhepatic disease entities with and without coma.

An unusual type of primary myocardial disease with metabolic changes peculiar to this series has been described. Severe myocardial degeneration and cardiac failure initiated a series of events, including metabolic acidosis, marked elevations of serum enzyme activity and accumulation of plasma lactic acid, that appear to have contributed significantly to the severity of the disease. The possibility that the metabolic derangements and hepatic disease represent primary effects of an agent that also produces myocardial failure must be seriously considered.

Vallee has emphasized the occurrence of increased urinary zinc, decreascd serum zinc, and low hepatic zinc content in postalcoholic cir­ rhosis. He has suggested that high concen­ trations of blood alcohol inhibit the zinc-containing metalloenzyme, alcohol de­ hydrogenasc, and account, in a manner un­ determined, for the increased zincuria. 4 The increase in urine zinc content and decrease in serum zinc concentration might result however, from a primary abnormality in renal function. The nephrotic syndrome is associated with a severe increase in urinary zinc excretion 5 and demonstrates that excess amounts of zinc may bc excreted in the urine secondary to renal disease. The most prominent changes in renal function observed in cirrhotic patients are the abnormalities in sodium and water excretion. The retention of salt and water and associated loss of potassium is thought to result from the effect of aldosterone on the renal tubules. 6

The clinical association of decreased serum and hepatic zinc in patients with cirrhosis of the liver presumably arising from excess ethanol ingestion prompted a study of the activities of zinc and alcohol in experimental animals. The purpose of this study was to determine the effect of zinc deficiency upon lipid peroxidation in the liver. The effect of ethanol and zinc deficiency on lipid peroxidation was also evaluated. Rats were used in the experimental design, one group received a control diet, and one was maintained on a zinc-deficient diet. One-half of each group also received 3.85 g ethanol per kilogram body weight daily. Lipid peroxidation in vivo was determined by estimation of diene conjugation of microsomal lipids. The in vitro lipid peroxidation potential was measured by the generation of malonic dialdehyde by enzymatic as well as nonenzymatic reactions. Analysis of this data indicated that increased hepatic microsomal lipid peroxidation was associated with zinc deficiency whether using in vivo or in vitro indices of measurement. Review of the data from individual animals indicated that the lowest levels of serum zinc were associated with increased hepatic content of phospholipids. The degree of lipid peroxidation in the zinc deficient animals was not increased by ingestion of alcohol.

The serum levels and urinary excretion of magnesium and copper were studied in 66 patients with either acute myocardial ischemia or myocardial infarction. Serum for magnesium and copper determinations was obtained daily for three days. The initial serum magnesium levels were normal in patients with ischemia but were low in some patients with myocardial infarction. Patients developing ventricular arrhythmias with myocardial infarction showed the lowest levels of serum magnesium. Copper in the serum appeared elevated in patients developing acute congestive heart failure but the elevation was not statistically significant. These data indicate that a decrease in serum magnesium as evaluated may be associated with ventricular arrhythmias in patients with myocardial infarction; thus continued observations of magnesium levels in the myocardial infarction patient is warranted.

Excerpt Carcinoma of the colon is a common disease. What is not appreciated is that it is one of the most common malignant growths found in young adults. Although there is ample literature dealing ...

The procedures and equipment needed to measure filtration efficiency by means of fluorescent aerosols are described. The filtration efficiency of individual lots of spun-glass air filtration medium or of entire air filtration systems employing such media was determined. Data relating to the comparative evaluation of spun-glass filter media by means of the fluorometric method described, as well as by conventional biological procedures, are presented.

SummaryAn evaluation. of thiamine activity, magnesium levels, and plasma lactate levels in chronic alcoholics demonstrated the expected common occurrence of deficiencies in each, but failed to show a correlation of these parameters in the individual alcoholic patients.

Liver samples obtained from 43 consecutive autopsies were analyzed for their content of zinc, hydroxyproline and nitrogen. Mean liver zinc was 2.36 and 1.27µg/mg nitrogen for histologically normal and cirrhotic samples, respectively. Hepatic zinc did not correlate with hepatic hydroxyproline. It is concluded that there is an absolute reduction in zinc content of cirrhotic liver and that this reduction bears no relationship to the amount of collagen present. If low levels of zinc in liver can be equated with zinc deficiency, patients with Laennec's cirrhosis are deficient in zinc.

A finger-mounted pipetting device which can be fabricated in the laboratory is described.