Structure of dense liquid water by neutron scattering to 6.5 GPa and 670 K.

We present a neutron diffraction study of liquid water to 6.5 GPa and 670 K. From the measured structure factors we determine radial and angular distributions. It is shown that with increasing density water approaches a local structure common to a simple liquid while distorting only a little the tetrahedral first-neighbor coordination imposed by hydrogen bonds that remain intact.

Nature of the polyamorphic transition in ice under pressure.

We present a neutron diffraction study of the transition between low-density and high-density amorphous ice (LDA and HDA, respectively) under pressure at approximately 0.3 GPa, at 130 K. All the intermediate diffraction patterns can be accurately decomposed into a linear combination of the patterns of pure LDA and HDA. This progressive transformation of one distinct phase to another, with phase coexistence at constant pressure and temperature, gives direct evidence of a classical first-order transition. In situ Raman measurements and visual observation of the reverse transition strongly support these conclusions, which have implications for models of water and the proposed second critical point in the undercooled region of liquid water.

[Geriatrics-quo vadis? The system of geriatric care]. / Geriatrie-quo vadis?Zur Struktur geriatrischer Versorgung.

The authors describe the current and perspective structure of geriatric care in hospital and rehabilitation units. First the specific needs of elderly patients with various medical problems (multiple morbidity) are described. Furthermore the article analyses optimised structures of geriatric care. These visions are not limited to care in hospital and rehabilitation units but include prevention and long term care for elderly people as well.

Impact of age on reference values for serum concentration of cystatin C in children.

Recently, cystatin C (cyst C) was proposed for the assessment of glomerular filtration rate, being more accurate than creatinine determination. Reference intervals for cyst C do not vary with age and sex, like creatinine values. Elevated values of cyst C were reported for pre- and full-term infants. Nevertheless, the age cut-off for stable cyst C values i.e., age independence, remains under discussion. Therefore, we conducted a prospective study in 98 healthy children, 51 being under 18 months of age. Cyst C was determined by the nephelometric method. The infants under the age of 18 months had a higher mean serum cyst C value (0.94 +/- 0.24 mg/l) than the older children (0.65 +/- 0.19 mg/l). There was a negative correlation between age and cyst C in the infant group under the age of 18 months (r(2)=0.631, P<0.01). Our results indicate that mean serum cyst C is higher in infants than older children; the age cut-off appears over the age of 1 year of life, presumably reflecting kidney maturation. Our study does not allow accurate assessment of the age cut-off at 18 months or 36 months.

Structure of high-density amorphous ice under pressure.

We report in situ neutron diffraction studies of high-density amorphous ice (HDA) at 100 K at pressures up to 2.2 GPa. We find that the compression is achieved by a strong contraction ( approximately 20%) of the second neighbor coordination shell, so that at 2.2 GPa it closely approaches the first coordination shell, which itself remains intact in both structure and size. The hydrogen bond orientations suggest an absence of hydrogen bonding between first and second shells and that HDA has increasingly interpenetrating hydrogen bond networks under pressure.

Analysis of allelic imbalance in patients with colorectal cancer according to stage and presence of synchronous liver metastases.

OBJECTIVE: To investigate the relationship between number and location of allelic imbalances (AI) and local tumor progression according to Astler-Coller classification. SUMMARY BACKGROUND DATA: Spontaneous errors in DNA replication (i.e., allelic imbalance or microsatellite instability) have been suggested to play an important role in carcinomatous transformation as reflecting alterations of gene function. METHODS: One hundred two consecutive patients with colorectal carcinoma undergoing surgical resection were included in this study. Patients were distributed according to the Astler-Coller classification as stages A (n = 7), B1 (n = 15), B2 (n = 24), C (n = 31), and D (n = 25). Fluorescent polymerase chain reaction was performed on frozen tumor, normal colon mucosa, and blood DNA at 35 microsatellite markers. Allelic imbalance frequency was compared with tumor staging. RESULTS: The percentage of AI was significantly higher in stage D than in A/B1 and B2. In addition, the percentage of AI was significantly higher in 10 synchronous colorectal liver metastases than in stage A/B1 and B2 tumors. However, the allelotyping revealed a subgroup of A/B1 tumors with a high AI frequency. Statistical analysis showed that the presence of AI at microsatellites D1S305, D2S138, D3S1282, D17S790, and D22S928 presented a significantly positive correlation with stages. CONCLUSION: The frequency of AI significantly correlates with tumor progression of colorectal cancer. Primary tumors with synchronous colorectal liver metastases showed a higher percentage of AI, suggesting that a frequency of AI greater than 35% with this selection of markers indicates a high risk of local progression and of development of metastases.

[Chronic experimental bacteremia in Yucatan micropigs]. / Bactériémie chronique expérimentale du microporc Yucatan.

The Yucatan micropig has been used to develop an experimental model of chronic bacteremia. This animal exhibits clinical and biological characteristics that are close to those in humans, and the pharmacokinetic behaviours of many classes of drugs in this model are similar to those in man. Six adult female were intravenously inoculated with a mean Escherichia coli inoculum of 5.1 x 10(9) bacteria. During five days of spontaneous evolution, the medical follow-up includes biological, clinical and bacteriological parameters. A systemic inflammatory syndrome, a sepsis, an organ insufficiency and positive blood cultures mimic the human disease. In all animals there is an adynamia, a lack of motor coordination, an anorexia, a tachypnea, a fever, a leuconeutropenia followed by an hyperleucocytosis, an anemia, a thrombopenia, an acute tubulonephritis and an elevated sedimentation rate. In some cases, there is an increase of the C reactive protein, in others, an increase of IL-6 and IL-8. At day five, all animals are alive, and five micropigs have positive blood cultures. This chronic, reproducible model is thus suitable for further antibacterial treatments evaluations.

Adoption of smart cards in the medical sector: the Canadian experience.

This research evaluates the factors influencing the adoption of smart cards in the medical sector (a smart card has a micro-processor containing information about the patient: identification, emergency data (allergies, blood type, etc.), vaccination, drugs used, and the general medical record). This research was conducted after a pilot study designed to evaluate the use of such smart cards. Two hundred and ninety-nine professionals, along with 7248 clients, used the smart card for a year. The targeted population included mostly elderly people, infants, and pregnant women (the most intensive users of health care services). Following this pilot study, two surveys were conducted, together with numerous interviews, to assess the factors influencing adoption of the technology. A general picture emerged. indicating that although the new card is well-perceived by individuals, tangible benefits must be available to motivate professionals and clients to adopt the technology. Results show that the fundamental dimension that needs to be assessed before massive diffusion is the relative advantage to the professional. The system must provide a direct benefit to its user. The relative advantage of the system for the professional is directly linked to the obligation for the client to use the card. The system is beneficial for the professional only if the information on the card is complete. Technical adequacy is a necessary but not sufficient condition for adoption.

Pressure-induced hydrogen bonding: structure of D2S phase I'

The full structure of the high-pressure cubic phase I' of hydrogen sulfide has been solved using neutron diffraction data. The molecules are partially rotationally disordered about the <111> axes, as in phase II at ambient pressure but with markedly greater nonuniformity of the toroidal D distribution. The changes in structure at the II-->I' transition signal the onset of significant pressure-induced hydrogen bonding.

Bringing Silicon Valley inside.

In 1998, Silicon Valley companies produced 41 IPOs, which by January 1999 had a combined market capitalization of $27 billion--that works out to $54,000 in new wealth creation per worker in a single year. Multiply the number of employees in your company by $54,000. Did your business create that much new wealth last year? Half that amount? It's not a group of geniuses generating such riches. It's a business model. In Silicon Valley, ideas, capital, and talent circulate freely, gathering into whatever combinations are most likely to generate innovation and wealth. Unlike most traditional companies, which spend their energy in resource allocation--a system designed to avoid failure--the Valley operates through resource attraction--a system that nurtures innovation. In a traditional company, people with innovative ideas must go hat in hand to the guardians of the old ideas for funding and for staff. But in Silicon Valley, a slew of venture capitalists vie to attract the best new ideas, infusing relatively small amounts of capital into a portfolio of ventures. And talent is free to go to the companies offering the most exhilarating work and the greatest potential rewards. It should actually be easier for large, traditional companies to set up similar markets for capital, ideas, and talent internally. After all, big companies often already have extensive capital, marketing, and distribution resources, and a first crack at the talent in their own ranks. And some of them are doing it. The choice is yours--you can do your best to make sure you never put a dollar of capital at risk, or you can tap into the kind of wealth that's being created every day in Silicon Valley.

Glucose-charged dialysate for children on hemodialysis: acute dialytic changes.

Glucose has been omitted from hemodialysates in the recent past. Currently, there is a tendency to include glucose in dialysates at physiological concentrations between 100 and 200 mg/dl (5.56-11.12 mmol/l). In adult patients, this induces, over the dialysis session, a significant uptake of glucose, with some benefits, i.e., avoidance of caloric loss, but also with some metabolic risks, i.e. decreased dialytic potassium removal secondary to an insulin-dependent intracellular potassium shift. We have performed a crossover study in five stable children (mean age 11.7 years) with normal fasting glucose on chronic bicarbonate hemodialysis. The dialysis prescription of 3-h sessions was changed only in terms of the glucose dialysate concentration, being either glucose free or containing 9.17 mmol/l (165 mg/dl) glucose; dialysates were potassium free. Twenty sessions were analyzed for each group by whole dialysate collection (glucose, potassium, phosphate) and serum concentration analysis during and post dialysis (glucose, potassium, phosphate, insulin). Glucose-free dialysis was associated with a patient net glucose loss of 113 +/- 12 mmol/session (nearly 20 g). Conversely, with the glucose-charged dialysate a small uptake of glucose was noted [13.8 +/- 2.1 mmol/session (nearly 2 g)]. At the end of the session, serum glucose was lower with the glucose-free dialysate (4.64 +/- 0.52 mmol/l) than the glucose-charged dialysate (6.11 +/- 0.92 mmol/l). Conversely, serum insulin was higher with the glucose-charged dialysate (38 +/- 17 mU/l) than the glucose-free dialysate (19 +/- 9 mU/l). There were no significant differences either for dialytic removal of potassium (70 vs. 73 mmol/session) or phosphate (20 vs. 22 mmol/session), with and without glucose dialysates. Our study, contrary to previously published data in adults, demonstrated that in children the use of a physiological concentration of glucose in the dialysate (165 mg/dl) avoids dialytic glucose loss without a significant decrease in dialytic potassium removal.

Impact of increased intraperitoneal fill volume on tolerance and dialysis effectiveness in children.

The known relationship between peritoneal fill volume (IVP) and dialysis efficiency favors the use of an optimal IVP to enhance peritoneal dialysis (PD). Therefore, we have studied the effects of an increased IVP in consecutive stages [800, 1400, and 2000 mL/m2 of body surface area (BSA), respectively] in 8 children on chronic PD (mean age: 9 years 6 months; range: 2-16 years). Each prescribed IVP was maintained for 60 minutes of dwell time, allowing a short peritoneal equilibration test. Tolerance was assessed clinically and by intraperitoneal pressure (IPP) measurements at the end of each dwell test. Determination of dialysate-to-plasma ratios, and calculation of mass transfer area coefficients (K0A) using the Henderson method for urea, creatinine, and phosphate, were used to assess the impact of an increased IVP on dialytic efficiency. Increasing IVP from 800 to 1400 and thereafter to 2000 mL/m2 induced an IPP increment, respectively, from 8.4 +/- 1.4 cm (of water) to 12.1 +/- 1.4 cm and thereafter to 18.3 +/- 1.4 cm, with a positive strong linear correlation (r = 0.92; P = 0.001; IPP = 1.46 +/- 8.17(-3) IVP). In the same manner increasing IVP induced K0A increments for urea of 10.6 +/- 1.2 mL/min per m2 to 15.3 +/- 1.6 mL/min per m2 and 17.1 +/- 1.9 mL/min per m2; for creatinine of 7.9 +/- 0.09 mL/min per m2 to 11.2 +/- 0.18 mL/min per m2, and 12.3 +/- 0.21 mL/min per m2; and for phosphate of 5.2 +/- 0.08 mL/min per m2 to 6.7 +/- 0.09 mL/min per m2 and 6.6 +/- 0.07 mL/min per m2, respectively. When K0A values were normalized to the values achieved at the IVP of 1400 mL/m2, the K0A gain obtained increasing IVP from 1400 to 2000 mL/m2 was only significant for urea, peaked for creatinine, and even slowly decreased for phosphate. Moreover, a fill volume over 1400 mL/m2, which appears to be the optimal volume in terms of dialysis efficiency, was only barely tolerated with clinical signs of discomfort and an increased IPP. Therefore, in our opinion, the maximal IVP in children over the age of 2 years should be nearly 1400 mL/m2, both in terms of abdominal tolerance and in terms of urea, creatinine, and phosphate peritoneal membrane purification capacities.

Early assessment of transplanted liver function: lignocaine clearance test (MEGX).

The purpose of this study was to assess the value of lignocaine biotransformation into monoethylglycinexylidide (MEGX) and conventional liver function tests in the early post-operative period as an indicator of graft function and as a diagnostic tool for complications after hepatic transplantation. Monoethylglycinexylidide formation, plasma bilirubin, aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), factor V index (FVI) and prothrombin time index (PTI) were measured in 71 patients undergoing 80 liver transplantations respectively at 12 (T1), 24 (T2), 48 (T3) and 72 h (T4) after liver graft revascularization. Patients were divided into two group according to the post-operative outcome. Patients with favourable outcome (n = 59) had significantly higher monoethylglycinexylidide synthesis, higher factor V index and prothrombin time index plasma concentrations, lower bilirubin, ASAT and ALAT plasma concentration (P < 0.0001 at T2 and T3) than those with complicated time course (n = 21). Monoethylglycinexylidide synthesis was the best discriminant of a favourable outcome, whereas bilirubin and ALAT concentrations were associated with complications (bilirubin for primary non function [PNF], ALAT for acute rejection). Thus, the combination of parameters at T2 was a very efficient predictor of primary non function, acute rejection and an uncomplicated time course.

Strategy as revolution.

How often does the strategic-planning process start with senior executives asking what the rest of the organization can teach them about the future? Not often enough, argues Gary Hamel. In many companies, strategy making is an elitist procedure and ¿strategy¿ consists of nothing more than following the industry's rules. But more and more companies, intent on overturning the industrial order, are rewriting those rules. What can industry incumbents do? Either surrender the future to revolutionary challengers or revolutionize the way their companies create strategy. What is needed is not a tweak to the traditional strategic-planning process, Hamel says, but a new philosophical foundation: strategy is revolution. Hamel offers ten principles to help a company think about the challenge of creating truly revolutionary strategies. Perhaps the most fundamental principle is that so-called strategic planning doesn't produce true strategic innovation. The traditional planning process is little more than a rote procedure in which deeply held assumptions and industry conventions are reinforced rather than challenged. Such a process harnesses only a tiny proportion of an organization's creative potential. If there is to be any hope of industry revolution, senior managers must give up their monopoly on the creation of strategy. They must embrace a truly democratic process that can give voice to the revolutionaries that exist in every company. If senior managers are unwilling to do this, employees must become strategy activists. The opportunities for industry revolution are mostly unexplored. One thing is certain: if you don't let the revolutionaries challenge you from within, they will eventually challenge you from without--in the marketplace.