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Aims To develop and validate a non-invasive method for measuring myocardial iron in order to allow diagnosis and treatment before overt cardiomyopathy and failure develops.Methods and Results We have developed a new magnetic resonance T2-star (T2*) technique for the measurement of tissue iron, with validation to chemical estimation of iron in patients undergoing liver biopsy. To assess the clinical value of this technique, we subsequently correlated myocardial iron measured by this T2* technique with ventricular function in 106 patients with thalassaemia major. There was a significant, curvilinear, inverse correlation between iron concentration by biopsy and liver T2* (r=0(.)93, P

Detailed measurements of the distribution of heat transfer and pressure, as well as Schlieren photographs, have been obtained in a series of experimental studies designed to provide measurements with which to evaluate the capabilities of the current numerical simulation techniques to predict the detailed characteristics of regions of shock/shock and shock/boundary layer interactions in laminar hypersonic flows. These experimental studies were conducted for a range of Mach numbers and Reynolds numbers to obtain fully laminar flows at conditions through the interaction regions that could be predicted with both DSMC and Navier-Stokes numerical schemes. In the first part of this paper, we present the model configuration, test condition and surface and flowfield measurements obtained in regions of shock/shock interaction over a highly instrumented cylindrical leading edge. In part two, only the model configurations, test conditions, and sample surface measurements are presented on two models—an axisymmetric cone/cone and a hollow cylinder flare configuration. The measurements that have been made on these configurations are being retained until the results of predictions with the DSMC and Navier-Stokes codes have been completed.

Clinical complications of transfusional iron overload are still common in patients with thalassaemia major (TM) and it is not clear how best to monitor body iron stores during long-term follow-up to anticipate tissue damage. In this study, we have reviewed a group of 32 patients who underwent liver biopsy between 1984 and 1986. We developed a method of assessing the trend in serum ferritin (TSF) during long-term monitoring and compared this with mean serum ferritin (MSF) and initial liver iron (LI) concentration to determine whether, individually or in combination, they were accurate in predicting clinical outcome. LI levels were low (7 mg/g), medium (7-15 mg/g) and high (15 mg/g dry weight) in 15, 7 and 10 patients respectively. MSF was low (1500 microg/l), medium (1500-2500 microg/l) and high (2500 microg/l) in 10, 14 and 8 patients. TSF was low, medium and high risk in 9, 9 and 11 out of 29 evaluable patients. During a median follow-up of 13.6 years (range 2.3-14.8 years) after biopsy, nine patients died and an additional three patients developed heart failure. Hypothyroidism developed in five, hypoparathyroidism in four, and diabetes mellitus in seven patients. Cirrhosis developed in four of 10 evaluable patients. The clinical end-point of death or cardiac failure was significantly associated with increasing iron load using all three means of assessment. Although numbers were insufficient for statistical analysis, MSF or TSF were more closely associated with complications of iron overload than LI. There was no clear additional value in combining LI with MSF or TSF. The data show that quantitation of liver iron from a single liver biopsy has little value in long-term monitoring of iron stores. Most complications can be avoided if ferritin levels can be brought down to1500 microg/l.

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily. Recent studies found that ligand-activated PPARgamma regulated differentiation and clonal growth of several types of cancer cells, including prostate cancer, suggesting that PPARgamma could be a tumor suppressor. Troglitazone was a widely used antidiabetic drug that activates PPARgamma. Recently, we reported that this agent had antiprostate cancer effects in vitro and in vivo. In this study, we administered troglitazone for over 1.5 years to an individual with occult recurrent prostate cancer. Using the prostate-specific antigen (PSA) levels as a surrogate marker of the disease, the oral administration of troglitazone (600-800 mg/day) reduced the increase velocity of PSA levels, suggesting clinical efficacy of troglitazone in prostate cancer. PSA promoter/ enhancer reporter assays showed that the PPARgamma ligands troglitazone (10(-5) M), pioglitazone (10(-5) M), or 15-deoxy-delta12,14-prostaglandin J2 (10(-5) M) down-regulated androgen-stimulated reporter gene activity in LNCaP cells, a prostate cancer cell line. The PSA promoter contains androgen receptor response elements (AREs). Reporter gene studies showed that troglitazone inhibited androgen activation of the AREs in the PSA regulatory region. Consistent with inhibition of gene expression, 2 days of incubation of LNCaP with troglitazone dramatically suppressed PSA protein expression without suppressing AR expression, suggesting that troglitazone inhibited ARE activation by a mechanism other than down-regulation of expression of the AR. Taken together, ligands of PPARgamma may be a useful therapeutic approach for the treatment of prostate cancer and may be acting, in part, by inhibiting transactivation of androgen-responsive genes.

The Employee Benefit Research Institute (EBRI) and the Investment Company Institute (ICI) have been collaborating for the past three years to collect data on participants in 401(k) plans. This effort, known as the EBRI/ICI Participant-Directed Retirement Plan Data Collection Project, has obtained data for 401(k) plan participants from certain of EBRI and ICI members serving as plan record keepers and administrators. The report includes 1998 information on 7.9 million active participants in 30,102 plans holding nearly $372 billion in assets. The data include demographic information, annual contributions, plan balances, asset allocation, and loans, and are broadly representative of the universe of 401(k) plans. The database also includes three years of longitudinal information on approximately 3.3 million participants. Key findings include: For all 401(k) participants in the 1998 EBRI/ICI database, almost three-quarters of plan balances are invested directly or indirectly in equity securities. Specifically, 49.8 percent of total plan balances are invested in equity funds, 17.7 percent in company stock, 11.4 percent in guaranteed investment contracts (GICs), 8.4 percent in balanced funds, 6.1 percent in bond funds, 4.7 percent in money funds, and 0.3 percent in other stable value funds. Participant asset allocation varies considerably with age. Younger participants tend to favor equity funds, while older participants are more disposed to invest in GICs and bond funds. On average, participants in their 20s have 62.1 percent of their account balances invested in equity funds, in contrast to 39.8 percent for those in their 60s. Participants in their 20s invest 4.7 percent of their assets in GICs, while those in their 60s invest 20.6 percent. Bond funds, which represent 4.7 percent of the assets of participants in their 20s, amount to 9.0 percent of the assets of participants in their 60s. Investment options offered by 401(k) plans appear to influence asset allocation. For example, the addition of company stock substantially reduces the allocation to equity funds and the addition of GICs lowers allocations to bond and money funds. The average account balance (net of plan loans) for all participants was $47,004 at year-end 1998, which is 26 percent higher than the average account balance at year-end 1996. The median account balance was $13,038 at year-end 1998. The balances, however, represent only amounts with current employers and do not include amounts remaining in the plans of prior employers. The average balances of older workers with long tenure indicate that a mature 401(k) plan program will produce substantial account balances. For example, individuals in their 60s with at least 30 years of tenure have average account balances in excess of $185,000. The ratio of account balance to 1998 salary varies with salary, increasing slightly as earnings rise from $20,001 to $80,000, and falling a bit for salaries greater than $80,000. The increase in ratio likely reflects a greater propensity of higher-income participants to save, whereas the decline after $80,000 results from contribution and nondiscrimination rule constraints.

Management of prostate cancer that has spread beyond the capsule is a difficult problem. Innovative and nontoxic approaches to the disease are urgently required. Recently, a commercially available herbal mixture called PC-SPES showed potent antitumor activities on a variety of malignant cells in vitro.PC-SPES was evaluated for its ability to inhibit clonal growth, and to induce cell cycle arrest of three human prostate cancer cell lines (LNCaP, PC-3, and DU 145). Western blot analysis examined the effect of PC-SPES on levels of p21(waf1), p27(kip1), Bcl-2, and E-cadherin in the three cell lines; and telomerase activity was examined by telomeric repeat amplification protocol (TRAP) assay. Furthermore, the effect of oral PC-SPES (250 mg/kg/day) on growth of PC-3 and DU 145 tumors present in male BNX nu/nu triple immunodeficient mice was studied. LNCaP cells were not analyzed in mice because they grow only with difficulty in these immunodeficient mice.PC-SPES markedly inhibited clonal growth of LNCaP, PC-3, and DU 145 prostate cancer cells, with a 50% inhibition (ED50) at approximately 2 microl/ml. Pulse-exposure studies showed that a 5-day pulse-exposure to PC-SPES (2 microl/ml) in liquid culture achieved a 50% inhibition of PC-3 clonal growth in soft agar, suggesting that the growth inhibition mediated by the extracts remained after removal of PC-SPES. Cell cycle analysis using the prostate cancer cell lines found that PC-SPES induced a significant increase in the number of cells in G0-G1 and G2/M, with a concomitant decrease in the number of cells in S phase. PC-SPES (2 microl/ml, 4 days) increased slightly the levels of p21(waf1) in the three cell lines, decreased by 40% the levels of Bcl-2 in PC-3, and the levels of p27(kip1) and E-cadherin and telomerase were unchanged in each of the lines. In vivo treatment with oral PC-SPES of male BNX mice having DU 145 tumors produced significant inhibition of their growth (P0.001), with no objective side effects including blood chemistries, weights, or autopsy analysis. The PC-SPES showed no statistical effect on the in vivo growth of PC-3 cells.PC-SPES inhibits clonal proliferation of human prostate cancer cells both in vitro and in vivo, using a murine model.

With the continued increase in medical expenditures and the growing awareness that resources are not limitless, there is increasing pressure to curb health care costs and to establish priorities. As potential solutions are proposed and implemented, there is understandable concern that policy choices may adversely affect both the access to and the quality of care. Economic analyses are one tool used to optimize resource allocation decisions. The primary goal of these analyses is to maximize value and efficiency, not necessarily to decrease spending. The current focus on cost cutting is often associated with a more truncated, nonsocietal perspective (e.g., that of the payer or provider). To be most useful, these analyses must be methodologically rigorous. Standard guidelines, such as those established by Eisenberg, are helpful. As shown in the reports applicable to head and neck malignancies that have been discussed here, many articles published in the clinical literature must be interpreted cautiously, because fundamental methodological concerns (e.g., using costs rather than charges, discounting to a common base year) were frequently not addressed. Economic investigations are one aspect of the broader fields of outcomes and health services research. It is easy to underestimate how greatly economic studies depend on the availability of high quality noneconomic data. In that context, current initiatives in evidence-based medicine (EBM), using the best available evidence (considering for example, the type of trial, the quality of the research, and the credentials of the researcher) to help clinicians practice in situations where doubt may exist in the diagnosis, treatment, or prognosis of patients, will likely grow in importance. Evidence-based clinical practice guidelines and systematic literature reviews are manifestations of this trend. Historically, disease control measures and survival have been the primary and points in clinical cancer studies. Economic analyses and studies evaluating other end points (e.g., function, quality of life) will likely play a larger role in the future in evaluating the diagnosis, treatment, and follow-up of head, neck and other malignancies.

Low livestock productivity in many developing countries is commonly considered to reflect, among other factors, the inadequate supply of services to control disease. Veterinary services have traditionally been provided by the state, but public finance constraints have limited the availability and effectiveness of public services. The author explains how economic theory can be used to identify alternative delivery systems (beyond the state) for providing animal health care and proposes new roles for the state and private sector in service delivery. The author highlights a number of barriers that currently limit the potential contribution of the private sector to service delivery, and describes a variety of approaches that have been used by the state to create an enabling environment for the private sector.

Troglitazone, a thiazolidinedione derivative, is a widely used antidiabetic drug that binds and activates peroxisome proliferator-activated receptor gamma (PPARgamma) and enhances insulin sensitivity. It induces differentiation of adipocytes, which highly express PPARgamma. We report that human prostate cancer cells expressed PPARgamma at prominent levels and normal prostate tissues had very low expression. Dose-response clonogenic assays of the PC-3 prostate cancer cell line with troglitazone showed an antiproliferative effect (ED50, 3 x 10(-7) M) and other PPARgamma ligands (BRL49653: ED50, 8 x 10(-8) M; 15-deoxy-delta12,14-prostaglandin J2: ED50, 2 x 10(-6) M; ciglitizone: ED50, not reached; indomethacin: ED50, not reached) showed similar effects. Combinations of troglitazone and a ligand specific for either retinoid X receptor or retinoic acid receptor did not show a synergistic effect. Pulse-exposure to troglitazone (10(-5) M) for different durations showed that 4 days of pulse-exposure to the agent irreversibly inhibited 50% clonal growth of PC-3 cells. Interestingly, PC-3 cells cultured with troglitazone (10(-5) M) showed dramatic morphological changes both by light and electron microscopy, suggesting that the cells became less malignant. Nevertheless, troglitazone did not affect either the cell cycle or several markers of differentiation. LNCaP cells constitutively produced prostate-specific antigen, and levels were markedly enhanced by all-trans-retinoic acid. Troglitazone (10(-5) M, 4 days) decreased by 50% the levels of prostate-specific antigen produced by these cells. In vivo treatment of PC-3 tumors growing in male BNX triple immunodeficient mice with oral troglitazone (500 mg/kg/day) produced significant inhibition of tumor growth (P = 0.01). The only objective side effect of troglitazone in mice was the elevation of serum transaminases. Short-term culture of four surgically obtained human prostate cancer tumors with troglitazone (10(-5) M, 4 days) produced marked and selective necrosis of the cancer cells (about 60%) but not the adjacent normal prostate cells. Taken together, these results suggest that troglitazone may be a useful therapeutic agent for the treatment of prostate cancer, especially in the setting of low disease burden.

IL-12 is a complex cytokine in both its structure and its range of biologic activities. Fusions of this heterodimeric molecule with an intact antitumor Ab were made to test the feasibility and efficacy of targeting IL-12 to tumors to elicit a local immune response. Fusion proteins composed of the human p35 and p40 subunits had IL-12 bioactivities that were nearly as potent on human immune cells as the rIL-12 standard, but were inactive on mouse cells. Hybrid IL-12 fusion proteins composed of mouse p35 and human p40, fused to Ab, were capable of inducing IFN-gamma, but were much less active on mouse spleen cells than a mouse IL-12 standard. Despite this relatively low activity, the hybrid fusion protein was as effective in a SCID mouse model as a fully active Ab-IL-2 fusion protein in eliminating established pulmonary metastases of CT26 colon carcinoma. Specific targeting of a human IL-12 fusion protein to metastatic prostate carcinoma xenografts was also shown to be effective in SCID mice transplanted with human lymphocyte-activated killer cells. These results demonstrate the importance of directing this potent cytokine to the tumor microenvironment and suggest an important alternative to systemic IL-12 administration or gene therapy for increasing its therapeutic index.

Management of prostate cancer that either is detectable by prostate specific antigen (PSA) measurements after curative intent or has spread outside of its capsule is a serious problem. Innovative, nontoxic approaches to the disease are required. One approach might be therapy with retinoids. Retinoid activities are mediated by two distinct families of transcription factors: the retinoic acid receptors (RARs) and retinoid X receptors (RXRs), which can induce transcriptional activation through specific DNA sites or by inhibiting the transcription factor AP-1 that usually mediates cellular proliferative signals. The RARs require heterodimerization with RXRs. RXRs can form either heterodimers or homodimers; and the latter can bind to DNA response elements that are distinct from those bound by the RAR/RXR heterodimers.A series of novel synthetic retinoids that selectively interact with RXR/RXR homodimers or RAR/RXR heterodimers, or that selectively inhibit AP-1 activity without activating transcription were evaluated for their ability to inhibit clonal growth of three human prostate cancer cell lines (PC-3, DU-145, and LNCaP).Several notable findings were: 1) RXR-selective retinoids, such as SR11246, were able to inhibit the clonal growth of prostate cancer cells. In contrast, SR11246 had little effect on clonal growth of myeloid leukemic cells. 2) RAR-selective retinoids also inhibited clonal growth of prostate cancer cells. 3) The retinoid (SR11238) with potent anti-AP-1 activity had no effect on the clonal growth of prostate cancer cells.This study shows that both RXR- and RAR-selective retinoids are worthy of further study and may be candidates for future clinical trials in prostate cancer.

Management of prostate cancer that has spread outside of the prostate capsule is a difficult problem. Innovative, non-toxic approaches to the disease are required. New, relatively non-toxic vitamin D3 analogs have recently been synthesized. We report that several of these compounds have marked antiproliferative effects on prostate cells.The clonal antiproliferative activity of five novel analogs of 1,25 dihydroxyvitamin D3 [1,25(OH)2D3, (cmpd C)] as well as 1,25(OH)2D3 itself was tested on three human prostate cancer cell lines (PC-3, LNCaP, and DU-145). The analogs were 20-epi-22oxa-24a,26a,27a-tri-homo-1 alpha,25(OH)2D3 (code name: KH 1060); 24a26a27a-tri-homo-22,24-diene-1 alpha,25(OH)2D3 (code name: EB 1089); 1,25(OH)2-16ene-D3 (code name: HM); 1,25(OH)2-16ene-23yne-D3 (code name: V); 1,25(OH)2-20-epi-D3 (code name: MC 1288)].With the parent compound [1,25(OH)2D3], the effective dose that inhibited 50% clonogenic growth of PC-3 and LNCaP was 10(-8)M and 7 x 10(-9)M, respectively. For these prostate cancer cell lines, KH 1060 was the most potent analog by an order of 25- to 35-fold as compared to cmpd C. The second and third most potent analogs were HM and MC 1288. DU-145 was resistant to all the vitamin D3 analogs. The major side-effect of 1,25(OH)2D3 is the production of hypercalcemia. The relative inhibitory index (RII) was determined by comparing the antiproliferative activity of the analog to its ability to produce hypercalcemia in mice injected intraperitoneally every other day. The KH 1060 had the best RTI: 50- to 70-fold greater than 1,25(OH)2D3 for PC-3 and LNCaP, respectively.A trial of one or more of these innovative compounds should be considered for treatment of minimal residual disease of prostate cancer.

Objective To examine the effects of sucrose on pain and biochemical markers of adenosine triphosphate (ATP) degradation and oxidative stress in preterm neonates experiencing a clinically required heel lance. Study design Preterm neonates that met study criteria (n = 131) were randomized into 3 groups: (1) control; (2) heel lance treated with placebo and non-nutritive sucking; and (3) heel lance treated with sucrose and non-nutritive sucking. Plasma markers of ATP degradation (hypoxanthine, xanthine, and uric acid) and oxidative stress (allantoin) were measured before and after the heel lance. Pain was measured with the Premature Infant Pain Profile. Data were analyzed by the use of repeated-measures ANOVA and Spearman rho. Results We found significant increases in plasma hypoxanthine and uric acid over time in neonates who received sucrose. We also found a significant negative correlation between pain scores and plasma allantoin concentration in a subgroup of neonates who received sucrose. Conclusion A single dose of oral sucrose, given before heel lance, significantly increased ATP use and oxidative stress in premature neonates. Because neonates are given multiple doses of sucrose per day, randomized trials are needed to examine the effects of repeated sucrose administration on ATP degradation, oxidative stress, and cell injury.

Objectives: The extent and mechanism of cross-infection with Pseudomonas aeruginosa (PA) in specialist cystic fibrosis (CF) units remain controversial. Prevention of droplet spread by segregation and use of single patient rooms is advised by most authorities. Despite these measures, many centres continue to report outbreaks of clonal “epidemic” strains. We conducted an aerobiological study to examine airborne dispersal of PA in a large CF centre in the UK. Methods: Microbiological air sampling was conducted in outpatient and inpatient areas inhabited by patients known to harbour the Liverpool Epidemic Strain (LES) of PA. A volumetric air sampler was placed at least 1m from patients, working at a rate of 100 L/min with a sampling time of 10min. Any colonies growing on Pseudomonas selective agar were identified by phenotypic and molecular methods and the number of colony-forming units (CFUs) counted. Conclusion: Out of 177 samples obtained from 8 separate patient environments, 33 (19%) grew PA. Contamination was greater in patient rooms than corridor areas; 23% (29/125) vs 10% (4/51) respectively. Rooms inhabited by 3 of 8 patients yielded positive growth. Corridor air was positive in the vicinity of 1 patient’s closed room. Samples from this patient’s room demonstrated much higher counts than those from other rooms (mean 61CFU/m3 vs 0−3CFU/m3). These data confirm that PA can contaminate air >1m from patients and suggest that certain patients may act as “super-shedders”. Ventilation strategies and infection control precautions in CF centres should take into account the possibility of true airborne transmission of PA.

A longitudinal electromyographic study of the swallowing activity of the anterior temporal and masseter muscles was performed on 21 subjects with complete dentures. In six patients, the lip activity was recorded. At the pretreatment stage, when the patients had a residual anterior dentition, the peak mean voltages of the elevators showed low values (range 18 to 30 microV), and after denture placement, the anterior temporal muscles showed a further decrease. After denture relining, slight increases in temporal activity were noted at the 1-year stage. During the second year, when no corrections of the dentures were made, the temporal activity decreased below the pretreatment level. The masseter activity showed no significant changes during the 2-year observation period. The mandibular lip showed significantly stronger swallowing activity than the maxillary lip. The mean durations of the swallows were markedly longer than values reported for subjects with a complete natural dentition.

Introduction The exact incidence of Helicobacter pylori (HP) in childhood is unknown. There is a causal link between HP and development of peptic ulcers, gastric adenocarcinoma and lymphoma. However there is little evidence and guidance on the clinical management of HP in children. The North American Society for Paediatric Gastroenterology and Nutrition report there is no compelling evidence to treat children colonised with HP without histological evidence of gastritis. This reflects the current pathophysiological understanding of cancer development, where inflammation secondary to infection is believed to be the driver of dysplasia and cancer. In our tertiary referral centre current practice stains all paediatric gastric biopsies with Haematoxylin and Eosin stain (H+E) as well as Warthin Starry (WS) stain, specifically for HP-like organisms. The aim of this study was to investigate the incidence of HP infection in children undergoing endoscopy. We also examined the routine use of special staining on all gastric biopsies for HP and whether other histological features on H+E examination could act as reliable markers of infection allowing selective special staining. Methods We reviewed all gastric biopsies submitted between January 8 and September 11, in patients born after 1989. All reports were loaded onto a database and searched for key words with “helico”, “HLO” and “ H Pylori ”. Each report was then examined for evidence of HP, acute inflammation and lymphoid aggregates. Results 1102 cases were examined and 23/1102 were positive for HP, 2% of all cases. There was acute inflammation in 17/23 cases. In the six with no acute inflammation, two were suspected of having HP (one previously treated) and one had only a single biopsy from the body, not the antrum. 146/1102 (13%) cases had acute inflammation. Acute inflammation as a marker for HP has a sensitivity of 74%, specificity of 88%, PPV of 11% and NPV of 99%. Lymphoid aggregates and acute inflammation as markers of infection further increased HP detection. Conclusion This study shows our current practice involves special staining of all biopsies for low prevalence disease (2%). However H+E examination alone has low sensitivity for picking up HP in cases of low density infection. Acute inflammation as a marker for HP infection could aid selection of cases for special staining. The NPV of 99% suggests that very few cases would be missed. Selective staining of cases for HP would also save around £3000/year (excluding pathologist time). The disadvantage that a small number of children colonised with HP, without gastritis may be missed is of unclear significance. Further research is required in order to develop an integrated clinical and pathological approach into the investigation, diagnosis and treatment of HP in children. Competing interests None declared.

In this paper we describe the hypervelocity facilities and instrumentation for the aerothermal and aero-optical studies of hypersonic interceptors. We first review the major fluid dynamic phenomena that control the flowfield environment around an interceptor. The key role of duplicating flowfield velocity for the simulation of both fluid dynamic and real-gas effects is discussed. The design and operating characteristics of the Large Energy National Shock tunnel (LENS) facility is then described, and the test conditions that will be obtained for endointerceptor studies are discussed. The surface and flowfield instrumentation that will be used to determine the aerothermal characteristics of the flowfield over the hypersonic vehicle is described. Finally we discuss the aero-optic instrumentation which is used to evaluate the optical degradation through the shock layer surrounding the vehicle.

A longitudinal electromyographic study of the anterior temporal and masseter activity during habitual chewing of apple was performed on 21 subjects provided with immediate complete dentures. At the pretreatment stage, when the patients having an anterior residual dentition were chewing, the peak mean voltages showed low values (range, 48 to 58 microV). After denture placement, there was a further decrease of the temporal activity that persisted to the 6-month stage. After the dentures were relined, a significant increase in chewing force of the temporal muscles was noted at the 1-year stage. During the second year, when no corrections of the dentures were made, the temporal activity decreased below the pretreatment level. The masseter muscle chewing activity generally showed no significant changes during the 2-year observation period. The mean durations of the chewing strokes and chewing cycles were longer than values reported in dentate samples and generally displayed no significant changes during the 2-year period.

The creation of an overseas mental health crisis intervention team is described. The authors discuss the unique aspects of an overseas low intensity conflict environment and the importance of immediate mental health responses to disaster situations in such theaters. Key elements in the formation of the team are the use of local resources, command endorsement, and an emphasis on education of commanders and team members. Examples are cited of other military response team deployments. The authors present their experience in Panama as a model for other providers in similar environments.

In the preceding article, the authors described the formation of an overseas mental health crisis intervention team. In this paper, the application of the United States Southern Command Crisis Intervention Team in the aftermath of a recent tragedy in Panama is described. A chronology of the disaster, involving two helicopter crashes which left 11 dead, is presented. The intervention that followed is described in detail. The emphasis is on four main areas: education, identification, process, and follow-up. The authors present their experience in an effort to provide an intervention strategy for other isolated mental health providers.

A program of experimental research and analysis was conducted to examine the heat transfer and pressure distributions in regions of shock/shock interaction over smooth and transpiration-cooled hemispherical noseshapes. The objective of this investigation was to determine whether the large heat transfer generated in regions of shock/shock interaction can be reduced by transpiration cooling. The experimental program was conducted at Mach numbers of 12 to 16 in the Calspan 48-Inch Shock Tunnel. Type 3 and type 4 interaction regions were generated for a range of freestream unit Reynolds numbers to provide shear layer Reynolds numbers from 10 exp 4 to 10 exp 6 to enable laminar and turbulent interaction regions to be studied. Shock/shock interactions were investigated on a smooth hemispherical nosetip and a similar transpiration-cooled nosetip, with the latter configuration being examined for a range of surface blowing rates up to one-third of the freestream mass flux. While the heat transfer measurements on the smooth hemisphere without shock/shock interaction were in good agreement with Fay-Riddell predictions, those on the transpiration-cooled nosetip indicated that its intrinsic roughness caused heating-enhancement factors of over 1.5. In the shock/shock interaction studies on the smooth nosetip, detailed heat transfer and pressure measurements were obtained to map the variation of the distributions with shock-impingement position for a range of type 3 and type 4 interactions. Such sets of measurements were obtained for a range of unit Reynolds numbers and Mach numbers to obtain both laminar and turbulent interactions. The measurements indicated that shear layer transition has a significant influence on the heating rates for the type 4 interaction as well as the anticipated large effects on type 3 interaction heating. In the absence of blowing, the peak heating in the type 3 and type 4 interaction regions, over the transpiration-cooled model, did not appear to be influenced by the model's rough surface characteristics. The studies of the effects of the transpiration cooling on type 3 and type 4 shock/shock interaction regions demonstrated that large surface blowing rates had significant effect on the structure of the flowfield, enlarging the shock layer and moving the region of peak-heating interaction around the body.

A lack of user acceptance of authentication systems costs organisations money and sometimes deters users from doing their jobs. Despite recent research on the usability of authentication systems, there is little empirical or theoretical understanding of user preferences in authentication systems. This research, based on a comparison of user preferences and performance between alphanumeric passwords and the graphical password, PassFaces™, identifies two user preference factors for authentication systems. There were no significant user performance differences between the two systems. A rank-ordered list of user preferences for usability and security in authentication systems offers organisations potential criteria for evaluating authentication systems.

A theoretical study was conducted to determine the effects of adverse pressure gradient and compressibility in modeling turbulent compressible flows. The kinetic energy/dissipation and Reynolds stress model predictions are presented and compared with experimental data. The effects of compressibility, which include the mass averaged fluctuation term, the pressure dilatation term, and the dilatation dissipation, are important in modeling the turbulent compressible flows. The normal stresses and longitudinal strain rates also have an effect in the prediction of turbulent energy productions on the curved surfaces. A new compressible formulation of the pressure strain term, which includes the dilatation effects, in the Reynolds stress equation is presented.

The preparation of tricarbonyl(2-trimethylstannylcycloheptadiene)iron and tricarbonyl(2-trimethylsilylcycloheptadiene)iron is described. Hydride abstraction from these complexes, using triphenylmethyl hexafluorophosphate, leads to tricarbonyl(3-trimethyl-stannyl- and -silyl-cycloheptadienyl)iron complexes. Reaction of the trimethylstannyl-substituted dienyl complex with enolate nucleophiles gives the expected addition products, together with almost equal amounts of diene-Fe(CO)3 complexes resulting from a nucleophile addition/protiodestannylation reaction. The trimethylsilylcycloheptadienyl complex is better behaved, giving good yields of nucleophile addition products. Cyanide anion adds to this complex to give exclusively the C(1) addition product, in contrast to tricarbonylcycloheptadienyliron cation, which gives mixtures of C(1) and C(2) addition products. Treatment of tricarbonyl(5-methyl-3-trimethylsilylcyclohepta-1,3-diene)iron with triphenylmethyl hexafluorophosphate resulted in loss of a methyl group to give tricarbonyl(3-trimethylsilylcycloheptadienyl)iron hexafluorophosphate, a highly unusual reaction.

Meldrum's acid or 2,2-dimethyl-1,3-dioxane-4,6-dione undergoes a Knoevenagel condensation with formaldehyde to form an active Michael acceptor for a second molecule of Meldrum's acid. The structure of the resulting product is determined by correlation of the products of possible reactions of Meldrum's acid and formaldehyde with the NMR spectrum of the product.

The utilization of the Biginelli reaction, a one-pot condensation of an aldehyde, a β-keto ester, and urea, is described. This reaction involves a number of individual steps, each of which is accessible to first-year organic students. The product, a 3,4-dihydropyrimidinone, is a member of a medicinally useful class of compounds. The reaction is simple to perform and the product precipitates from solution in an extremely pure form.

The use of alumina-supported active MnO2 to oxidize benzoin to benzil is described. The advantages of this reagent include ease of handling and separation from the product and lower toxicity than previously reported supported oxidizing agents. The product is purified by elution through a simple chromatography column consisting of a silica gel-packed Pasteur pipet. Students' yields are comparable to yields from other reported oxidation methods.

Accompaniment to Organic Chemistry by the same authors. Fifty animations that can be viewed in a ball-and-stick, space-filling, HOMO, or LUMO mode. The animations can be put on a slow-motion setting to permit better visualization and are accompanied by an energy diagram, making it easy to identify transition states and intermediates. Electron flow is apparent in the HOMO and LUMO modes, allowing the student to link curved arrows and orbital interactions.

Some texts have begun to integrate the biologically oriented topics into the text, but Thomas N. Sorrell's Organic Chemistry has taken this approach to new heights.

A solid acid-catalyzed version of the Pechmann reaction for the synthesis of coumarins is described. The Pechmann reaction is a multiple-transformation process which is not a part of the normal organic chemistry curriculum. However, each transformation (hydroxyalkylation, transesterification, dehydration) is one that can be understood by students, and by applying the known mechanisms in sequence, the correct product can be predicted.

The general framework that Jones uses is that of Lewis acids reacting with Lewis bases, with an emphasis on the interaction of filled and empty orbitals. Again and again, as you work your way through the text, there are examples of reactions being explained by the overlap of orbitals.

The Chem TV: Organic Chemistry series is a two-CD-ROM set, with the material divided loosely along the lines of material typically covered in the two semesters of introductory organic chemistry. Each CD-ROM contains sections on Structure, Reactions, and Special Topics; Organic Chemistry II also has treatment of Biochemical Structures and a selection of Self-Tests.

The large number of biology majors and prehealth students enrolled in Organic Chemistry makes it desirable to have laboratories that involve biologically interesting molecules. Although many laboratory manuals contain sections on carbohydrate chemistry, the experiments are typically limited to esterification or hydrolysis reactions. A recent publication (Toshima, K.; Ishizuka, T.; Matsuo, G.; Nakata, M. Synlett. 1995, 306. ) on the glycosidation of glycals offered a different possibility.

In Dickinson's chemistry curriculum, "Synthesis and Reactivity" replaces the traditional organic chemistry sequence and begins in the second semester of the freshman year. A key aspect of our seque...

The effect of cisapride, a new gastrointestinal prokinetic agent, on the transit of a standard meal through the stomach, small intestine and colon was studied in 10 normal subjects. Cisapride had no significant effect on gastric emptying but decreased mouth to caecum transit time (p less than 0.01). Stool weight and frequency were not significantly increased but the time for the first appearance of stool markers and the arrival of 20% and 50% of stool markers was decreased after cisapride (p less than 0.05).

Reactions en position 3 de l'hexahydro-1,3a,4,5,6,6a iodo-3 methyl-2 tosyl-1 cyclopenta [b] pyrrole catalysees par Pd(0) (carbonylation, insertion d'olefines, transmetallation)

Gastric emptying half-time and mouth to caecum transit time of a solid meal were measured in eight normal volunteers, once during a period of psychological stress and again during a period of relative calm. No consistent or significant effect on gastric emptying was observed, but mouth to caecum transit times were faster in all subjects and this difference was highly significant (p

Changes occur in the structure of drawn polyethylene when it is annealed at temperatures close to that of the drawing process. Measurements have been made of the oxygen barrier properties and of the thermal expansion coefficient in the draw direction on samples over a wide draw ratio range both before and after annealing at various temperatures. The results are augmented by density, creep modulus, and shrinkage observations. All samples show a drop in the barrier properties and an increase in the thermal expansion after annealing. However, whereas high-draw-ratio samples show relatively small effects, the changes observed at low draw ratios are very large, with some barrier properties even lower than those of the isotropic feedstock. The effects are larger at the higher annealing temperatures. The diffusion and expansion measurements are greatly influenced by the amorphous regions in the polymer; these results are interpreted as a relaxation of internal stresses giving rise to greater accessibility of the intercrystalline regions. Further experimental work is required to exploit these techniques.

Measurements of permeability and diffusivity have been undertaken for the gases helium and oxygen in a range of highly oriented polyethylene films. The solubilities deduced for both gases are proportional to the amorphous volume fraction, showing that the noncrystalline regions are the transport medium in all instances. The changes in diffusion coefficient are more complex. A large reduction in diffusion coefficient is observed with increasing draw ratio, and this is particularly marked in the case of the larger oxygen molecule, where significant differences are also observed for different grades of polymer and different drawing conditions. These changes in diffusion coefficient are discussed in the light of previous studies of diffusion in polymers and present knowledge of the changes in structure produced by drawing.