Randomized clinical trial of remote ischaemic preconditioning versus no preconditioning in the prevention of perioperative myocardial infarction during open surgery for ruptured abdominal aortic aneurysm.

BACKGROUND: Remote ischaemic preconditioning (RIPC) has been suggested as a means of protecting vital organs from reperfusion injury during major vascular surgery. This study was designed to determine whether RIPC could reduce the incidence of perioperative myocardial infarction (MI) during open surgery for ruptured abdominal aortic aneurysm (AAA). Secondary aims were to see if RIPC could reduce 30-day mortality, multiple organ failure, acute intestinal ischaemia, acute kidney injury and ischaemic stroke. METHODS: This randomized, non-blinded clinical trial was undertaken at three vascular surgery centres in Denmark. Patients who had open surgery for ruptured AAA were randomized to intervention with RIPC or control in a 1 : 1 ratio. Postoperative complications and deaths were registered, and ECG and blood samples were obtained daily during the hospital stay. RESULTS: Of 200 patients randomized, 142 (72 RIPC, 70 controls) were included. There was no difference in rates of perioperative MI between the RIPC and control groups (36 versus 43 per cent respectively), or in rates of organ failure. However, in the per-protocol analysis 30-day mortality was significantly reduced in the RIPC group (odds ratio 0·46, 95 per cent c.i. 0·22 to 0·99; P = 0·048). CONCLUSION: RIPC did not reduce the incidence of perioperative MI in patients undergoing open surgery for ruptured AAA. Registration number: NCT00883363 ( http://www.clinicaltrials.gov).

Replication of optical microlens array using photoresist coated molds.

A cost reduced method of producing injection molding tools is reported and demonstrated for the fabrication of optical microlens arrays. A standard computer-numerical-control (CNC) milling machine was used to make a rough mold in steel. Surface treatment of the steel mold by spray coating with photoresist is used to smooth the mold surface providing good optical quality. The tool and process are demonstrated for the fabrication of an ø50 mm beam homogenizer for a color mixing LED light engine. The acceptance angle of the microlens array is optimized, in order to maximize the optical efficiency from the light engine. Polymer injection molded microlens arrays were produced from both the rough and coated molds and have been characterized for lenslet parameters, surface quality, light scattering, and acceptance angle. The surface roughness (Ra) is improved approximately by a factor of two after the coating process and the light scattering is reduced so that the molded microlens array can be used for the color mixing application. The measured accepted angle of the microlens array is 40° which is in agreement with simulations.

Effects of diet energy concentration and an exogenous carbohydrase on growth performance of weanling pigs fed diets containing canola meal produced from high protein or conventional canola seeds.

The objectives were to determine effects of diet NE and an exogenous carbohydrase on growth performance and physiological parameters of weanling pigs fed a corn-soybean meal (SBM) diet or diets containing high protein canola meal (CM-HP) or conventional canola meal (CM-CV). A total of 492 pigs (initial BW: 9.15 ± 0.06 kg) were used in a randomized complete block design with 12 dietary treatments and 9 pens per treatment. A control diet based on corn and SBM and 4 diets containing 20% or 30% CM-HP or 20% or 30% CM-CV were formulated to a similar NE by adjusting inclusion of choice white grease. Four additional diets also contained 20% or 30% CM-HP or 20% or 30% CM-CV, but no additional choice white grease, and NE in these diets, therefore, was less than in the control diet. The control diet and the diets containing 30% CM-HP or CM-CV without increased choice white grease were also formulated with inclusion of an exogenous carbohydrase. Pigs were fed experimental diets for 22 d and 1 pig per pen was sacrificed at the conclusion of the experiment. Results indicated that compared with the control diet, there was no impact of canola meal on final BW, ADG, ADFI, or G:F, but pigs fed CM-CV had greater ( < 0.05) final BW, ADG, and ADFI than pigs fed CM-HP, and pigs fed diets with reduced NE had greater ( < 0.05) ADG and ADFI than pigs fed diets with constant NE. Only minor effects of CM-HP or CM-CV on intestinal weight, gut fill, digesta pH, cecal VFA concentrations, and serum concentrations of urea N, total N, or albumin were observed, but the weight of the thyroid gland increased ( < 0.05) as the concentration of dietary canola meal increased. Serum concentrations of IgG were reduced if canola meal was included in the diets without the carbohydrase, but that was not the case if the carbohydrase was included in the diet (interaction, ( < 0.05). In conclusion, up to 30% CM-HP or CM-CV in diets fed to weanling pigs from 2 wk postweaning did not impact growth performance compared with pigs fed a corn-SBM diet, and NE in diets containing canola meal does not have to be similar to that of corn-SBM diets. However, inclusion of CM-CV containing 4.43 µmol/g glucosinolates in the diets resulted in improved growth performance compared with inclusion of CM-HP containing 12.60 µmol/g glucosinolates.

Normalized performance and load data for the deepwind demonstrator in controlled conditions.

Performance and load normalized coefficients, deriving from an experimental campaign of measurements conducted at the large scale wind tunnel of the Politecnico di Milano (Italy), are presented with the aim of providing useful benchmark data for the validation of numerical codes. Rough data, derived from real scale measurements on a three-bladed Troposkien vertical-axis wind turbine, are manipulated in a convenient form to be easily compared with the typical outputs provided by simulation codes. The here proposed data complement and support the measurements already presented in "Wind Tunnel Testing of the DeepWind Demonstrator in Design and Tilted Operating Conditions" (Battisti et al., 2016) [1].

Male Sex Associated with Increased Long-term Cardiovascular Mortality after Peripheral Vascular Surgery for Atherosclerosis Despite Optimal Medical Treatment.

BACKGROUND: The cardiovascular burden and consequences of peripheral atherosclerosis appear to differ between men and women. Data regarding long-term outcomes, including the impact of medical prophylactic treatment, are insufficient. This study examined long-term outcomes according to sex following primary vascular surgery, adjusted for multiple variables as well as recommended medical prophylaxis. METHODS: All Danish patients who underwent peripheral vascular surgery from January 2000 to December 2007 were stratified into five procedural groups: (a) aorto-iliac bypass or thromboendarterectomy, (b) femoro-femoral crossover, (c) thromboendarterectomy of the femoral arteries, (d) infrainguinal bypass, or (e) axillo- uni-, and bifemoral bypass. Data were analyzed according to sex for differences in myocardial infarction, stroke, and death, individually and combined, after surgery. RESULTS: A total of 11,234 patients were included: 6,289 males and 4,945 females. The overall adjusted hazard ratio for male patients compared with female patients for death was 1.11 (95% CI 1.06-1.17), for MI was 1.16 (95% CI 1.04-1.29), for stroke was 0.99 (95% CI 0.89-1.11), and for any major adverse cardiovascular event was 1.10 (95% CI 1.05-1.16). CONCLUSIONS: These findings show that, despite indication, severity, and concomitant medical treatment of peripheral artery disease, men have a higher risk of mortality and adverse cardiovascular events following surgery for peripheral arterial disease.

Systolic myocardial velocity alterations in the growth-restricted fetus with cerebroplacental redistribution.

OBJECTIVES: Intrauterine growth restriction (IUGR) is associated with cerebroplacental redistribution (CPR), fetal stress and poor outcome, all of which may be related to dysfunction of the fetal myocardium. The aim of this study was to specifically assess myocardial function in IUGR fetuses with CPR in comparison with normal fetuses using color Doppler myocardial imaging (CDMI). METHODS: CDMI was used to evaluate and compare myocardial velocities in the left and right ventricles in normal fetuses and in IUGR fetuses with CPR. Peak systolic tissue velocities (S') were acquired from both ventricular free walls in 20 IUGR fetuses (gestational age at scan ranged from 26 + 1 to 34 + 6 weeks, with serial measurements obtained in nine) and 42 normal fetuses (35 at week 28, with the remaining seven undergoing serial scans every 4 weeks, ranging from 18 + 6 to 39 + 1 weeks). Umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV) flows were also recorded. RESULTS: Left and right S' increased with gestational age in normal pregnancy. Fetuses with IUGR and CPR had lower left ventricular S' than normal fetuses (mean, 2.41 (95% CI, 1.96-2.86) cm/s vs. 3.30 (95% CI, 3.05-3.55) cm/s; P = 0.0006). This reduction in S' correlated with the grade of UA flow abnormality (P = 0.0002). Fetuses with reversed diastolic UA flow had significantly lower left S' (mean, 2.0 (95% CI, 1.4-2.6) cm/s; P = 0.001) than normal fetuses. There was no correlation between left S' and MCA pulsatility index (P = 0.37) in the IUGR-CPR group, but there was a reduction in S' approaching statistical significance in fetuses with reversed DV flow in comparison to those without it (P = 0.09). Right S' was similar in the two study groups and did not correlate with worsening UA flow class. All fetuses with a left S' below 1.6 cm/s and reversed UA flow died in the perinatal period. CONCLUSIONS: CDMI facilitates acquisition of fetal myocardial ventricular S'. The combination of IUGR and CPR is associated with a reduced left ventricular S', especially in those with reversed UA flow. In this subgroup a left S' below 1.6 cm/s seemed to predict mortality in the perinatal period.

Sediment redox tracers in Strait of Georgia sediments--can they inform us of the loadings of organic carbon from municipal wastewater?

Organic carbon composition and redox element (Mn, Cd, U, Re, Mo, SigmaS, AVS) distributions are examined in seven 210Pb-dated box cores collected from the Strait of Georgia, British Columbia to evaluate the potential for redox elements to reveal impacts of anthropogenic loadings of labile organic carbon to sediments. In particular, the cores have been collected widely including regions far from local anthropogenic inputs and from locations within the zone of influence of two municipal outfalls where sediments are exposed to enhanced organic loadings from outfalls. We find a wide natural range in organic carbon forcing within the basin sediments generally reflected as Mn enrichments near the surface in cores exhibiting slow organic oxidation and sulphide, Cd, Mo, U and Re enrichments in cores exhibiting higher organic oxidation rates. Concentration profiles for redox elements or organic carbon are misleading by themselves, as they are influenced strongly by sediment porosity and sedimentation rate, and the organic matter remaining in sediment cores is predominantly recalcitrant. Fluxes of redox elements together with rates of organic metabolism estimated from sedimentation rates provide a better picture of the organic forcing. One core, GVRD-3, collected within the zone of influence of the Iona municipal outfall (0.5 km away), exhibits the highest organic carbon oxidation rates, enhanced Ag fluxes in the sediment surface mixed layer and altered delta15N composition, all of which implicate outfall particulates. Cd is also elevated in the GVRD-3 surface sediments, but evidence points to contamination and not redox forcing supporting this observation. Uranium also shows enrichment at sites near the outfalls, possibly in response to enhanced microbial metabolism. Predominantly these cores exhibit a wide natural range of organic carbon fluxes and organic carbon oxidation rates, supported by fluxes of marine and terrigenous organic carbon, within which it is difficult to identify any significant impact from municipal outfall organic carbon.

Glacial/interglacial changes in subarctic north pacific stratification.

Since the first evidence of low algal productivity during ice ages in the Antarctic Zone of the Southern Ocean was discovered, there has been debate as to whether it was associated with increased polar ocean stratification or with sea-ice cover, shortening the productive season. The sediment concentration of biogenic barium at Ocean Drilling Program site 882 indicates low algal productivity during ice ages in the Subarctic North Pacific as well. Site 882 is located southeast of the summer sea-ice extent even during glacial maxima, ruling out sea-ice-driven light limitation and supporting stratification as the explanation, with implications for the glacial cycles of atmospheric carbon dioxide concentration.

Gas compression in lungs decreases peak expiratory flow depending on resistance of peak flowmeter.

It has recently been shown (O. F. Pedersen T. R. Rasmussen, O. Omland, T. Sigsgaard, P. H. Quanjer. and M. R. Miller. Eur. Respir. J. 9: 828-833, 1996) that the added resistance of a mini-Wright peak flowmeter decreases peak expiratory flow (PEF) by approximately 8% compared with PEF measured by a pneumotachograph. To explore the reason for this, 10 healthy men (mean age 43 yr, range 33-58 yr) were examined in a body plethysmograph with facilities to measure mouth flow vs. expired volume as well as the change in thoracic gas volume (Vb) and alveolar pressure (PA). The subjects performed forced vital capacity maneuvers through orifices of different sizes and also a mini-Wright peak flowmeter. PEF with the meter and other added resistances were achieved when flow reached the perimeter of the flow-Vb curves. The mini-Wright PEF meter decreased PEF from 11.4 +/- 1.5 to 10.3 +/- 1.4 (SD) l/s (P < 0.001), PA increased from 6.7 +/- 1.9 to 9.3 +/- 2.7 kPa (P < 0.001), an increase equal to the pressure drop across the meter, and caused Vb at PEF to decrease by 0.24 +/- 0.09 liter (P < 0.001). We conclude that PEF obtained with an added resistance like a mini-Wright PEF meter is a wave-speed-determined maximal flow, but the added resistance causes gas compression because of increased PA at PEF. Therefore, Vb at PEF and, accordingly, PEF decrease.

[Calcium blood changes in septic conditions. A review]. / Calciumaendringer i blodet ved septiske tilstande. En oversigt.

Hypocalcemia has been reported in critically ill patients over the last 10-15 years, however, measurements of Ca2+ in blood have not yet became routine in the treatment of severely ill patients. In order to stress the importance of calcium in such patients, a review of calcium changes in septic conditions is presented. In vitro studies show that the intracellular calcium metabolism is disturbed in these patients, and that the changes in extracellular calcium are probably secondary to the intracellular changes. Parathyroid hormone secretion is inappropriate in septic patients. The reason for this is unknown. Administration of calcium parenterally does not seem to affect the prognosis, however calcium seems to be beneficial in patients with hypotension. Since the level of Ca2+ in blood may have prognostic significance in septic patients, measurements of Ca2+ in blood should be used routinely in these patients, in order to point out "risk" patients as early as possible.

On the natural enrichment of cadmium and molybdenum in the sediments of Ucluelet Inlet, British Columbia.

Cadmium concentrations in Ucluelet Inlet sediments are usually high compared with most marine environments, ranging up to 8 micrograms g-1. The distribution of the element is closely correlated with Mo, organic carbon and total nitrogen in depth profiles at three stations. Paradoxically, organic carbon concentrations are high in inlet sediments, reaching up to 9 wt.%, although the sedimentation rate determined from 210Pb measurements is low at all three sites (less than 0.03 to 0.28 cm year-1). C:N ratio data indicate a mixed marine-terrigenous provenance for the organic material and a relatively recent increase in the terrigenous proportion which probably represents wood debris associated with logging and log booming activity in the area. The complete absence of Mn enrichments in surface sediments, coupled with qualitative observations that H2S is present at very shallow depths, strongly suggest that the deposits are anoxic very near the sediment-water interface. The Cd and Mo enrichments are not due to anthropogenic inputs but are instead ascribed to diffusion of the dissolved metals from overlying seawater into the slowly-accumulating, organic-rich, anoxic sediments and their fixation in the solid phase as CdS and as a coprecipitate with FeS, respectively.