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BACKGROUND: Aortic root evaluation is conventionally based on two-dimensional measurements at a single phase of the cardiac cycle. This work presents an image analysis method for assessing dynamic three-dimensional changes in the aortic root of minimally calcified bicuspid aortic valves (BAVs) with and without moderate to severe aortic regurgitation. METHODS: The aortic root was segmented over the full cardiac cycle in three-dimensional transesophageal echocardiographic images acquired from 19 patients with minimally calcified BAVs and from 16 patients with physiologically normal tricuspid aortic valves (TAVs). The size and dynamics of the aortic root were assessed using the following image-derived measurements: absolute mean root volume and mean area at the level of the ventriculoaortic junction, sinuses of Valsalva, and sinotubular junction, as well as normalized root volume change and normalized area change of the ventriculoaortic junction, sinuses of Valsalva, and sinotubular junction over the cardiac cycle. RESULTS: Normalized volume change over the cardiac cycle was significantly greater in BAV roots with moderate to severe regurgitation than in normal TAV roots and in BAV roots with no or mild regurgitation. Aortic root dynamics were most significantly different at the mid-level of the sinuses of Valsalva in BAVs with moderate to severe regurgitation than in competent TAVs and BAVs. CONCLUSIONS: Echocardiographic reconstruction of the aortic root demonstrates significant differences in dynamics of BAV roots with moderate to severe regurgitation relative to physiologically normal TAVs and competent BAVs. This finding may have implications for risk of future dilatation, dissection, or rupture, which warrant further investigation.

Objectives This study explored whether the excess cardiovascular (CV) disease (CVD) risk in RA could be ameliorated by suppression of inflammation using a treat-to-target (T2T) approach. We compared the CV event (CVE) incidence among ERA patients managed by a T2T strategy with a CV risk factor-matched non-RA population and a historical RA cohort (HRA). Methods This was an observational study using the city-wide hospital data and the ERA registry. ERA patients received T2T management while HRA patients received routine care. Each ERA/HRA patient was matched to three non-RA controls according to age, gender and CV risk factors. Patients on antiplatelet/anticoagulant agents, with pre-existing CVD, chronic kidney disease or other autoimmune diseases were excluded. All subjects were followed for up to 5 years. The primary end point was the first occurrence of a CVE. Results The incidence of CVE in the ERA cohort (n = 261) and ERA controls were similar with a hazard ratio of 0.53 (95% CI 0.15, 1.79). In contrast, the incidence of CVE in the HRA cohort (n = 268) was significantly higher than that of the HRA controls with a hazard ratio of 1.9 (95% CI 1.16, 3.13). The incidence of CVE in the ERA cohort was significantly lower than that of the HRA cohort and the difference became insignificant after adjusting for inflammation, the use of methotrexate and traditional CV risk factors. Conclusion ERA patients managed by a T2T strategy did not develop excess CVE compared with CV risk factor-matched controls over 5 years.

Deep hypothermic perfusionless circulatory arrest was the first practical neuroprotective technique used for open-heart surgery. It was refined at the Novosibirsk Medical Research Center in Siberia and was actively used from the mid-1950s until 2001.This review describes the development of this technique and its contribution to our understanding of the dynamic changes in human physiology during induced hypothermia for circulatory arrest without extracorporeal perfusion. Deep hypothermic perfusionless circulatory arrest was an important stepping stone in the development of modern approaches in neuroprotection and monitoring during cardiac surgery.

A robust association between dispositional envy and happiness was primarily concluded among young adults. As social contexts can vary across developmental stages, the effect of dispositional envy may be enhanced or diminished in different age groups. Thus, the present research attempted to quantify the differential associations between dispositional envy and happiness among adolescents and young adults (N = 586). Moreover, we examined another important question of why the association differed across the two age groups. Using mediated moderation analysis, we found a stronger association between dispositional envy and happiness among young adults than adolescents. We also revealed that self-esteem was a valid mechanism to unpack the differential associations across two age groups.

Objectives: Repair for ischemic mitral regurgitation with undersized annuloplasty is characterized by high recurrence rates. We sought to determine the value of pre-repair 3-dimensional echocardiography over 2-dimensional echocardiography in predicting recurrence at 6 months.Methods: Intraoperative transesophageal 2-dimensional echocardiography and 3-dimensional echocardiography were performed in 50 patients undergoing undersized annuloplasty for ischemic mitral regurgitation. Two-dimensional echocardiography annular diameter and tethering parameters were measured in the apical 2-and 4-chamber views. A customized protocol was used to assess 3-dimensional annular geometry and regional leaflet tethering. Recurrence (grade >= 2) was assessed with 2-dimensional transthoracic echocardiography at 6 months.Results: Preoperative 2- and 3-dimensional annular geometry were similar in all patients with ischemic mitral regurgitation. Preoperative 2- and 3-dimensional leaflet tethering were significantly higher in patients with recurrence (n = 13) when compared with patients without recurrence (n = 37). Multivariate logistic regression revealed preoperative 2-dimensional echocardiography posterior tethering angle as an independent predictor of recurrence with an optimal cutoff value of 32.0 degrees (area under the curve, 0.81; 95% confidence interval, 0.68-0.95; P = .002) and preoperative 3-dimensional echocardiography P3 tethering angle as an independent predictor of recurrence with an optimal cutoff value of 29.9 degrees (area under the curve, 0.92; 95% confidence interval, 0.84-1.00; P Conclusions: Preoperative 3-dimensional echocardiography P3 tethering angle is a stronger predictor of ischemic mitral regurgitation recurrence after annuloplasty than preoperative 2-dimensional echocardiography posterior tethering angle, which is highly influenced by viewing plane. In patients with a preoperative P3 tethering angle of 29.9 degrees or larger (especially when combined with basal aneurysm/dyskinesis), chordal-sparing valve replacement should be strongly considered.

To determine the severity, duration, and contributing factors for metabolic acidosis after deep hypothermic circulatory arrest (DHCA).Retrospective observational study.University hospital.Eighty-seven consecutive patients undergoing elective thoracic aortic surgery with DHCA.Regression analysis was used to test for relationships between the severity of metabolic acidosis and clinical and laboratory variables.Minimum pH averaged 7.27±0.06, with 76 (87%) having a pH7.35; 55 (63%), a pH7.30; and 7 (8%), a pH7.20. The mean duration of metabolic acidosis was 7.9±5.0 hours (range: 0.0 - 26.8), and time to minimum pH after DHCA was 4.3±2.0 hours (1.0 - 10.0 hours). Hyperchloremia contributed to metabolic acidosis in 89% of patients. The severity of metabolic acidosis correlated with maximum lactate (p0.0001) and hospital length of stay (LOS) (r = 0.22, p0.05), but not with DHCA time, DHCA temperature, duration of vasoactive infusions, or ICU LOS. Patient BMI was the sole preoperative predictor of the severity of postoperative metabolic acidosis.This retrospective analysis involved short-term clinical outcomes related to pH severity and duration, which indirectly may have included the impact of sodium bicarbonate administration.Metabolic acidosis was common and severe after DHCA and was attributed to both lactic and hyperchloremic acidosis. DHCA duration and temperature had little impact on the severity of metabolic acidosis. The severity of metabolic acidosis was best predicted by the BMI and had minimal effects on short-term outcomes. Preventing hyperchloremic acidosis has the potential to decrease the severity of metabolic acidosis after DHCA.

Summary The anti-inflammatory actions of interleukin-10 (IL10) are thought to be mediated primarily by the STAT3 transcription factor, but pro-inflammatory cytokines such as interleukin-6 (IL6) also act through STAT3. We now report that IL10, but not IL6 signaling, induces formation of a complex between STAT3 and the inositol polyphosphate-5-phosphatase SHIP1 in macrophages. Both SHIP1 and STAT3 translocate to the nucleus in macrophages. Remarkably, sesquiterpenes of the Pelorol family, which we previously described as allosteric activators of SHIP1 phosphatase activity, could induce SHIP1/STAT3 complex formation in cells and mimic the anti-inflammatory action of IL10 in a mouse model of colitis. Using crystallography and docking studies we identified a drug-binding pocket in SHIP1. Our studies reveal new mechanisms of action for both STAT3 and SHIP1 and provide a rationale for use of allosteric SHIP1-activating compounds, which mimic the beneficial anti-inflammatory actions of IL10. Video Abstract, Graphical Abstract, Highlights • Loss of normal interleukin-10 (IL10) function results in inflammatory diseases • IL10 or SHIP1 agonists induce formation of SHIP1/STAT3 complexes • SHIP1 Y190 phosphorylation is required for SHIP1/STAT3 complex formation • SHIP1 agonists mimic IL10 anti-inflammatory action in a mouse model of colitis, Molecular Biology; Molecular Interaction; Immunity

Naturalistic stimuli such as watching a movie while in the scanner provide an ecologically valid paradigm that has the potential of extracting valuable information on how the brain processes complex stimuli in realistic visual and auditory contexts. Naturalistic viewing is also easier to conduct with challenging participant groups including patients and children. Given the high temporal resolution of MEG, in the present study, we demonstrate how a short movie clip can be used to map distinguishable activation and connectivity dynamics underlying the processing of specific classes of visual stimuli such as face and hand manipulations, as well as contrasting activation dynamics for auditory words and non-words. MEG data were collected from 22 healthy volunteers (6 females, 3 left handed, mean age – 27.7 ​± ​5.28 years) during the presentation of naturalistic audiovisual stimuli. The MEG data were split into trials with the onset of the stimuli belonging to classes of interest (words, non-words, faces, hand manipulations). Based on the components of the averaged sensor ERFs time-locked to the visual and auditory stimulus onset, four and three time-windows, respectively, were defined to explore brain activation dynamics. Pseudo-Z, defined as the ratio of the source-projected time-locked power to the projected noise power for each vertex, was computed and used as a proxy of time-locked brain activation. Statistical testing using the mean-centered Partial Least Squares analysis indicated periods where a given visual or auditory stimuli had higher activation. Based on peak pseudo-Z differences between the visual conditions, time-frequency resolved analyses were performed to assess beta band desynchronization in motor-related areas, and inter-trial phase synchronization between face processing areas. Our results provide the first evidence that activation and connectivity dynamics in canonical brain regions associated with the processing of particular classes of visual and auditory stimuli can be reliably mapped using MEG during presentation of naturalistic stimuli. Given the strength of MEG for brain mapping in temporal and frequency domains, the use of naturalistic stimuli may open new techniques in analyzing brain dynamics during ecologically valid sensation and perception.

To test whether health literacy is associated with sunlight exposure behavior, we interviewed 648 Chinese adults aged 65 years or older.Using the information-motivation-behavioral skills model and structural equation modeling, we tested whether health literacy was associated with the complex relationships among knowledge about vitamin D, attitudes toward sunlight exposure, doctor recommendations regarding sunlight exposure, and sunlight exposure behavior.Health literacy was directly associated with sunlight exposure (β=.20, p.01). Indirect relationships also existed between knowledge and sunlight exposure through health literacy (β=.46, p.001) and between attitudes and sunlight exposure through health literacy (β=-.12, p.05). The model had good fit (χ(2)/df=2.79; RMSEA=.053, p=.346; CFI=.95; TLI=.92).Health literacy should be considered when educating older adults about vitamin D supplements and sunlight exposure. Providing relevant knowledge or making doctor recommendations might not be effective. Training should focus on individuals with low health literacy who may be less likely to receive sunlight exposure.

Thermal comfort assessment is a prime measure in indoor environment design to evaluate occupant satisfaction. Fanger's thermal comfort model using heat balance theory conducted by chamber test has been widely adopted for thermal environment design criteria. However, rising numbers of thermal comfort field studies show that Fanger's model is not a good predictor of actual thermal sensation and many field measurements were statistically insignificant. This study proposes a Bayesian approach to update our current beliefs about thermal comfort and shows that the maximum likelihood of posterior estimates is close to the actual percentage dissatisfied (APD) obtained from large sample field surveys. For small sample sizes, the Bayesian estimation is close to Fanger's prediction and gives a solution for the discrepancy of Fanger's model. Congruence between Fanger's model prediction and contemporary field survey data is quantified. This quantitative assessment on the belief in newly yielded thermal comfort data can be a solution to the choice of thermal comfort criteria in future thermal environment designs.

Collaborator of ARF (CARF) has been shown to directly bind to and regulate p53, a central protein that controls tumor suppression via cellular senescence and apoptosis. However, the cellular functions of CARF and the mechanisms governing its effect on senescence, apoptosis, or proliferation are still unknown. Our previous studies have shown that (i) CARF is up-regulated during replicative and stress-induced senescence, and its exogenous overexpression caused senescence-like growth arrest of cells, and (ii) suppression of CARF induces aneuploidy, DNA damage, and mitotic catastrophe, resulting in apoptosis via the ATR/CHK1 pathway. In the present study, we dissected the cellular role of CARF by investigating the molecular pathways triggered by its overexpression in vitro and in vivo. We found that the dosage of CARF is a critical factor in determining the proliferation potential of cancer cells. Most surprisingly, although a moderate level of CARF overexpression induced senescence, a very high level of CARF resulted in increased cell proliferation. We demonstrate that the level of CARF is crucial for DNA damage and checkpoint response of cells through ATM/CHK1/CHK2, p53, and ERK pathways that in turn determine the proliferative fate of cancer cells toward growth arrest or proproliferative and malignant phenotypes. To the best of our knowledge, this is the first report that demonstrates the capability of a fundamental protein, CARF, in controlling cell proliferation in two opposite directions and hence may play a key role in tumor biology and cancer therapeutics.

Background The saddle shape of the normal mitral annulus has been quantitatively described by several groups. There is strong evidence that this shape is important to valve function. A more complete understanding of regional annular geometry in diseased valves may provide a more educated approach to annuloplasty ring selection and design. We hypothesized that mitral annular shape is markedly distorted in patients with diseased valves. Methods Real-time 3-dimensional echocardiography was performed in 20 patients with normal mitral valves, 10 with ischemic mitral regurgitation, and 20 with myxomatous mitral regurgitation (MMR). Thirty-six annular points were defined to generate a 3-dimensional model of the annulus. Regional annular parameters were measured from these renderings. Left ventricular inner diameter was obtained from 2-dimensional echocardiographic images. Results Annular geometry was significantly different among the three groups. The annuli were larger in the MMR and in the ischemic mitral regurgitation groups. The annular enlargement was greater and more pervasive in the MMR group. Both diseases were associated with annular flattening, although though the regional distribution of that flattening was different between groups. Left ventricular inner diameter was increased in both groups. However, relative to the Left ventricular inner diameter, the annulus was disproportionately dilated in the MMR group. Conclusions Patients with MMR and ischemic mitral regurgitation have enlarged and flattened annuli. In the case of MMR, annular distortions may be the driving factor leading to valve incompetence. These data suggest that the goal of annuloplasty should be the restoration of normal annular saddle shape and that the use of flexible, partial, and flat rings may be ill advised.

High-rise housing, a trend in densely populated cities around the world, increases the energy use for water supply and corresponding greenhouse gas emissions. This paper presents an energy efficiency evaluation measure for water supply system designs and a mathematical model for optimizing pumping energy through the arrangement of water tanks in a building. To demonstrate that the model is useful for establishing optimal design solutions that integrate energy consumption into urban water planning processes which cater to various building demands and usage patterns, measurement data of 22 high-rise residential buildings in Hong Kong are employed. The results show the energy efficiency of many existing high-rise water supply systems is about 0.25 and can be improved to 0.26–0.37 via water storage tank relocations. The corresponding annual electricity that can be saved is 160–410 TJ, a 0.1–0.3% of the total annual electricity consumption in Hong Kong.

Background The effect of aortic valve replacement on three-dimensional mitral annular geometry has not been well described. Emerging transcatheter approaches for aortic valve replacement employ fundamentally different mechanical techniques for achieving fixation and seal of the prosthetic valve than standard surgical aortic valve replacement. This study compares the immediate impact of transcatheter aortic valve replacement (TAVR) and standard surgical aortic valve replacement (AVR) on mitral annular anatomy. Methods Real-time three-dimensional echocardiography was performed in patients undergoing TAVR using the Edwards Sapien valve (n = 10 [Edwards Lifesciences, Irvine, CA]) or AVR (n = 10) for severe aortic stenosis. Mitral annular geometric indexes were measured using Tomtec EchoView (Tomtec Imaging Systems, Munich, Germany) to assess regional and global annular geometry. Results Mixed between-within analysis of variance showed no differences between TAVR and AVR groups in any of the mitral annular geometric indices preoperatively. However, postoperative analysis did demonstrate an effect of AVR on geometry. Patients undergoing open AVR had significant decrease in annular height, septolateral diameter, mitral valve transverse diameter, and mitral annular area after valve replacement (p ≤ 0.006). Similar changes were not noted in the TAVR group. Conclusions Mitral annular geometry is better preserved by TAVR than by AVR. Thus, TAVR may be a more physiologic approach to aortic replacement.

This study investigates the relationship between Indoor Environmental Quality (IEQ) and learning performance in air-conditioned university teaching rooms via subjective assessment and objective measurement. Together with the data of air temperature, relative humidity, air speed, mean radiant temperature, CO 2 concentration, equivalent sound pressure level, horizontal illumination level, occupant activity and clothing insulation level measured in four classrooms and four large lecture halls, self-reported learning performance (in calculating, reading, understanding and typing) and perceived IEQ are evaluated. The results show strong associations of the overall IEQ votes with the environmental parameters. While thermal comfort, indoor air quality and visual environment are of comparable importance, aural environment is the major determining factor. The study also reveals that all IEQ complaints have similar impact on learning performance and there is a good correlation between learning performance and the number of complaints. To aid design needs, empirical expressions that approximate the impact of unsatisfactory IEQ on learning performance loss are proposed.

The aim of this study was to investigate the prognostic value of the preoperative total lymphocyte count in peripheral blood as a predictor of postoperative complications and mortality in cardiac surgery.A retrospective, observational study.The Novosibirsk State Research Institute of Circulation Pathology (single institution).All adults undergoing primary cardiopulmonary bypass in 2009.None.The cohort size was 1,368 patients operated upon with cardiopulmonary bypass. Patient characteristics, hospital mortality, postoperative complications, ventilation time, intensive care unit, and hospital stay were analyzed. A preoperative total lymphocyte count1,500 cells/μL was associated with significantly higher mortality by univariate (p0.0001) and multivariate (p0.044) analyses. A low preoperative total lymphocyte count was associated with more frequent inotropic support (p0.001); postoperative heart arrhythmia (p0.001); dialysis-dependent acute renal failure (p0.001); and a prolonged ventilation time (p = 0.001), intensive care unit stay (p0.001), and hospital stay (p = 0.007).A low preoperative total lymphocyte count in peripheral blood is a useful prognostic criterion for the evaluation of a complicated postoperative period in cardiac patients operated under cardiopulmonary bypass.

Background A comprehensive three-dimensional echocardiography based approach is applied to preoperative mitral valve (MV) analysis in patients with ischemic mitral regurgitation (IMR). This method is used to characterize the heterogeneous nature of the pathologic anatomy associated with IMR. Methods Intraoperative real-time three-dimensional transesophageal echocardiograms of 18 patients with IMR (10 with anterior, 8 with inferior infarcts) and 17 patients with normal MV were analyzed. A customized image analysis protocol was used to assess global and regional determinants of annular size and shape, leaflet tethering and curvature, relative papillary muscle anatomy, and anatomic regurgitant orifice area. Results Both mitral annular area and MV tenting volume were increased in the IMR group as compared with patients with normal MV (mitral annular area=1,065 ± 59 mm 2 versus 779 ± 44 mm 2 , p = 0.001; and MV tenting volume=3,413 ± 403 mm 3 versus 1,696 ± 200 mm 3 , p = 0.001, respectively). Within the IMR group, patients with anterior infarct had larger annuli (1,168 ± 99 mm 2 ) and greater tenting volumes (4,260 ± 779 mm 3 versus 2,735 ± 245 mm 3 , p = 0.06) than the inferior infarct subgroup. Papillary-annular distance was increased in the IMR group relative to normal; these distances were largest in patients with anterior infarcts. Whereas patients with normal MV had very consistent anatomic determinants, annular shape and leaflet tenting distribution in the IMR group were exceedingly variable. Mean anatomic regurgitant orifice area was 25.8 ± 3.0 mm 2 , and the number of discrete regurgitant orifices varied from 1 to 4. Conclusions Application of custom analysis techniques to three-dimensional echocardiography images allows a quantitative and systematic analysis of the MV, and demonstrates the extreme variability in pathologic anatomy that occurs in patients with severe IMR.

Study objective We assessed whether the ordering of imaging studies in patients with suspected venous thromboembolism was consistent with the results of D-dimer testing. Methods We performed a retrospective chart review of consecutive cases in which a D-dimer assay was performed at an urban academic emergency department during a 13-month period. Measurements included D-dimer result and results of imaging for venous thromboembolism. The primary outcome measure was the percentage of patients in each D-dimer category (positive or negative result with a cutoff value of 500 ng fibrinogen equivalent units/dL) who underwent subsequent imaging within 48 hours. We also report the results of the imaging studies obtained. Results A total of 553 D-dimer tests were ordered, with 266 (48.1%) negative and 287 (51.9%) positive results. Of patients with a negative D-dimer result, 37 (14%; 95% confidence interval [CI] 10% to 19%) underwent at least 1 imaging study. Of patients with a positive D-dimer result, 137 (48%; 95% CI 42% to 54%) did not undergo imaging. Conclusion Evaluation for venous thromboembolism occasionally proceeded despite a negative D-dimer result, whereas frequently no further evaluation occurred despite a positive result. These findings suggest that actual clinical practice differs from what is recommended by published algorithms that guide evaluation of patients with suspected venous thromboembolism.

The influence of the alkali resistant surfactant Dowfax 2A1 on single ion track etching in 30 μm polycarbonate foils is studied at low etch rate (5 M NaOH at 41.5 ± 2 °C) using electro conductivity measurements. At surfactant concentrations above 10−4 vol.% break-through times are predictable (Δt/t

Backgound Stroke has emerged as an important complication of thoracic endovascular aortic repair (TEVAR). Identifying risk factors for stroke is important to define the risks of this procedure. Methods All neurologic complications were analyzed in a prospective database of patients in thoracic aortic stent graft trials from 1999 to 2006. Serial neurological examination was performed. Stroke was defined as any new onset focal neurologic deficit. Results The TEVAR was performed on 171 patients; 52 had lesions requiring coverage of the proximal descending thoracic aorta (extent A), 50 requiring coverage of the distal descending aorta (extent B), and 69 requiring coverage of the entire descending thoracic aorta (extent C). The incidence of stroke was 5.8%. Eighty-nine percent (8 of 9) of strokes occurred within 24 hours of operation. Stroke was associated with a 33% in-hospital mortality rate. Risk factors identified for stroke included prior stroke (odds ratio [OR] 9.4, confidence interval [CI] 2.3 to 38.1, p = 0.002) and extent A or C coverage (OR 5.5, CI 1.7–12.5, p = 0.001). The stroke rate in patients with both prior stroke and extent A or C coverage was 27.7%. Severe atheromatous disease involving the aortic arch by computed tomographic scan was strongly associated with perioperative stroke (OR = 14.8, CI 1.7 to 675.6, p = 0.0016). Transesophageal echocardiography demonstrated mobile atheroma in two patients with stroke. Conclusions Stroke after TEVAR was associated with a high mortality. The TEVAR of the proximal descending aorta (extent A or C) in patients with a history of stroke had the highest perioperative stroke rate. These risk factors, together with high grade aortic atheroma of the aortic arch, predicted a high probability for cerebral embolization and can be used to identify patients at high risk for stroke as a consequence of TEVAR.

A two-point maximum entropy regularization method (TPMEM) was investigated for signal enhancement of magnetoencephalography (MEG) data, as a potential replacement for current low-pass (LP) filtering techniques. TPMEM was found to have superior noise reduction and signal recovery capabilities over the LP filter, and MEG data processed with TPMEM yields less error in reconstructed dipole position and orientation.

Magnetoencephalography (MEG) was recorded while 5-7 year-old children were performing a visual-spatial memory recognition task. Full-term children showed greater gamma-band (30-50 Hz) amplitude in the right temporal region during the task, than children who were born extremely preterm. These results may represent altered brain processing in extremely preterm children who escape major impairment.

Room temperature measurements were made of electrical conductivity (σ), Hall coefficient (RH) and Seebeck coefficient (α) on filamentary samples of p-type CuInSe2 and CuIn1−xGaxSe2 with x⩽0.3, cut from vertically grown Bridgman ingots. Analysis of the results was done on a two-carrier basis, due to the higher ratio of electron to hole mobility (b) in these materials compared to elemental semiconductors. This treatment yielded a preferred b-value of 5 and to lower calculated hole concentrations than (RHe)−1 and higher hole mobilities than RHσ, based on a one-carrier interpretation. This effect was particularly marked in p-type samples with a hole concentration below 1017 cm−3, where even a few percent of minority electrons can play an important role.

Ingots containing single crystals of the quaternary alloys CuGaxIn1−xSe2 were grown by a vertical Bridgman method for compositions with x=0.2 and x=0.3. With stoichiometric Cu:(Ga+In):Se starting proportions in the ratio 1:1:2, respectively, all the ingots were p-type. X-ray powder diffraction and the observation, in ingot pieces, of cleavage in the unique {101} planes confirmed the crystal structure to be single-phase chalcopyrite. The lattice a-spacing decreased with increase of gallium content, as expected. Photovoltaic cells fabricated from wafers cut from the ingots showed the shift in quantum efficiency edge towards shorter wavelengths with an increase of x from 0 to 0.3. A Mott–Schottky plot for a cell made with CuGa0.2In0.8Se2 material yielded an apparent hole concentration of the order of 1016 cm−3. The quaternary ingots were found, in general, to be more brittle than ternary material grown by the same Bridgman procedures.

Repair of descending thoracic and thoracoabdominal aortic aneurysms (TAAAs) is associated with a substantial risk of perioperative spinal cord ischemia that may or may not lead to permanent postoperative paralysis. Several techniques that aim to increase the ischemia tolerance time of the spinal cord during the period of aortic cross-clamping have been described in the literature.1 Hypothermia, left heart bypass, various shunts, myriad drugs, and cerebrospinal fluid (CSF) drainage have all been used alone or in combination to potentially improve neurologic outcome after surgery. CSF drainage and distal aortic perfusion have been shown to lower the incidence of neurologic complications after repair of type I and type II TAAAs. 2 Distal aortic perfusion increases distal aortic pressure, and CSF drainage decreases CSF pressure. These techniques potentially lead to an augmentation of spinal cord perfusion pressure during the period of aortic cross-clamping. However, CSF drainage can be associated with potentially serious complications, including fracture of the catheter during removal, catheter-associated meningitis, and/or temporary abducens nerve palsy, among others. 3 Also, epidural hematoma at the catheter insertion site can complicate the clinical assessment of postoperative spinal ischemic injury. 4 Intracranial subdural hematomas, with excessive CSF drainage, have also been reported and are associated with significant morbidity and mortality. 5 Subsequently, some authors have challenged the efficacy of CSF drainage and question the acceptable risk: benefit ratio of the technique. 6,7

Objective : To evaluate multiplane transesophageal echocardiography (TEE) for detection of patent foramen ovale (PFO) and to compare multiplane TEE with visual inspection (VI) for PFO detection. Design : A prospective observational study. Setting : University hospital (single institution). Participants : Patients presenting for cardiac surgery requiring TEE. Interventions : Multiplane TEE including 2 atrial views with color-flow Doppler (CFD) and contrast echocardiography (CE) with a provocative respiratory maneuver (PRM) and comparison of multiplane TEE and VI with respect to PFO detection. Measurements and Main Results : The cohort size was 187. PFO prevalence was 27.3%. CFD with serial decrease of the Nyquist limit detected 51% of all PFO: 41.2% in the bicaval view alone, 27.5% in the 4-chamber view alone, and 9.8% in both views. CE detected 78.4% of all PFO: 72.5% with PRM, 45.1% with no PRM, and 27.4% with/without PRM. PFO detection by multiplane TEE and visual inspection were correlated in 41 subjects. TEE diagnosed 11 PFO (26.8% prevalence, 3 missed by VI). VI diagnosed 12 PFO (29.3% prevalence, 4 missed by TEE). Conclusions : Multiplane TEE is a gold standard for detection of PFO. Despite advances in TEE technology, 2-dimensional imaging does not detect all PFO. To maximize PFO detection, multiple TEE modalities are required in multiple views, despite a low Nyquist limit for CFD or a PRM for CE. Even though multiplane TEE is equivalent to VI for PFO detection, the discrepancy rate may be an important consideration in the individual case.

Emissions of air pollutants from aircraft in large urban areas are a health concern to nearby residents. This study examined hourly concentrations of CO, NOx ,S O 2, and respirable suspended particles (RSP) taken in the vicinity of Hong Kong InternationalAirport (HKIA) and Los Angel es InternationalAirport (LAX). The LAX data cover the period August 1997 through March 1998 and the HKIA all of 2000 and 2001. The average concentration as a function of wind speed and direction was estimated by nonparametric regression. The error variance of the nonparametric regression results was also estimated. The results show that SO2 can be used to identify wind speeds and directions associated with emissions from aircraft. Using this assumption and the nonparametric regression plots for the other pollutants one can identify the impact of aircraft on local air quality. At LAX, CO and NOx are dominated by emissions from ground vehicles going in and out of the airport. However, near HKIA, aircraft are an important contributor to CO and RSP. At both sites, nonparametric regression identified other, smaller sources as well. r 2004 Elsevier Ltd. All rights reserved.

Stroke occurs in 2% to 5% and cognitive dysfunction occurs acutely in 60% to 80% of patients early after cardiac surgery. Both may have long-term consequences. Research into mechanisms behind these sequelae has been focused intraoperatively, although there is little reason to believe that injury is limited to this period. Aging prominently increases the incidence of these sequelae. Anemia with cardiac surgery is acute and severe, should cause an increase in cerebral blood flow (CBF), and may impact stroke and cognitive function in this setting. To better understand changes in perioperative CBF physiology we have measured changes in CBF and the influence of anemia and aging on these changes.Cerebral blood flow was measured using the noninvasive continuous arterial spin labeling perfusion magnetic resonance imaging method. Cerebral blood flow, mean arterial pressure, hemoglobin, hemoglobin oxygen saturation, and cardiopulmonary bypass time were recorded in 12 subjects before and 6 +/- 2 days after cardiac surgery.Cerebral blood flow increased from 44.6 +/- 15.6 mL100 g(-1)min(-1) to 64.4 +/- 20.1 mL100 g(-1)min(-1) after cardiac surgery, or 49.1% +/- 26.7%, (p0.0001). The absolute change in CBF (DeltaCBF) was predicted by the following regression model: DeltaCBF = -55 + 0.64(Age) + 0.53(CBF(Pre)) -3.3(DeltaHgb); R(2) = 0.81; p = 0.003, where CBF(Pre) is the baseline preoperative CBF and DeltaHgb is the change in hemoglobin from preoperative to postoperative periods.Cerebral blood flow increases after cardiac surgery, and anemia appears to be an important cause. Age appears also to be an important covariate, with advancing age further increasing the magnitude of this hyperemia. The interrelationship of aging and anemia, in determining perioperative changes in CBF, and potentially cerebral oxygenation, may have important implications for the understanding of perioperative stroke and cognitive dysfunction after cardiac surgery.

The duration, severity, and cause of hypotension after intravenous amiodarone has not been well characterized in anesthetized cardiac surgical patients. Because amiodarone is tolerated in patients with advanced cardiac disease, we hypothesized that left ventricular systolic performance is preserved despite hypotension during amiodarone loading.In a prospective double-blind trial, 30 patients undergoing coronary artery bypass graft (CABG) surgery were randomly assigned to receive intravenous amiodarone (n = 15) or placebo (n = 15). Cardiac output (CO), mixed venous oxygen saturation (SVO), arterial blood pressure (systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP]), pulmonary artery pressure, and central venous pressure (CVP) were recorded. Transesophageal echocardiographic left ventricular end-diastolic area (EDA), end-systolic area (ESA), fractional area change (FAC), and end-systolic wall stress (ESWS) were measured every 5 minutes.Mean arterial pressure, SBP, and DBP decreased over time after drug administration in both groups (p0.05). At 6 minutes, amiodarone decreased the MAP by 14 mm Hg (p = 0.004) and placebo decreased the MAP by 4 mm Hg. The change in MAP, SBP, and DBP between groups was statistically different for the first 15 minutes after drug administration. Hypotension requiring intervention occurred in 3 of 15 after amiodarone and 0 of 15 after placebo (p = 0.22). The mean heart rate was 11.5 beats per minute less after amiodarone (p0.02), but pulmonary artery pressure, CVP, SVO, and FAC were not different between groups.Intravenous amiodarone decreased heart rate and caused a significant, but transient decrease in arterial pressure in the first 15 minutes after administration. Left ventricular performance was maintained suggesting that selective arterial vasodilation was the primary cause of drug-induced hypotension.

OBJECTIVES To review the clinical and social benefits of a pain management programme in Hong Kong. DESIGN Prospective cohort study. SETTING Tertiary out-patient clinic, Hong Kong. PARTICIPANTS Patients with chronic non-cancer pain and prolonged (mean, 46 months) psychosocial disability who joined the Comprehensive Outpatient Pain Engagement programme between 2002 and 2012. INTERVENTION A structured 6-week out-patient pain rehabilitation course designed to improve function and reduce disability, regardless of the cause or severity of pain. MAIN OUTCOME MEASURES Social outcomes included return-to-work rate, hospital admissions, and out-patient visits. Physical outcomes included tolerance to sitting and standing. Psychological constructs such as mood, catastrophisation, self-efficacy, quality of life, and perceived performances were used. Each measure was taken before and 1 year after the programme. RESULTS There was significant increase in return-to-work rate 1 year after commencement of the programme (35% after vs 17% before the programme; odds ratio=3.01), reduction in medical utilisation, and improvement in all physical and psychological measures. Pain intensity, psychological distress, and history of work-related injuries were not related to the likelihood of return to work. Shorter duration of pain and higher physical functioning score in 36-Item Short-Form Health Survey were prognostic indicators. CONCLUSIONS Patients with chronic pain who joined the Comprehensive Outpatient Pain Engagement programme showed significant functional improvement despite the long history of pain.

This study has demonstrated a simple fabrication process of a thin film ceramic relative humidity sensing chip at low temperature, 500°C. This process window to optimize sensitivity and hysteresis performance of the sensor has been studied using negative sputtering substrate bias and annealing duration. This proposed optimizing method yields an adjustable rutile/anatase phase ratio of titanium oxide. It shows improvement to the hysteresis of sensors and obtains good sensitivity, which is greater than four-orders of magnitude change in dc current over 11–97% relative humidity.

Background . Electrophysiologic studies during rewarming after deep hypothermic circulatory arrest probe the state of the brain during this critical period and may provide insight into the neurological effects of circulatory arrest and the neurologic outcome. Methods . Electroencephalogram (EEG) and evoked potentials were monitored during rewarming in 109 patients undergoing aortic surgery with hypothermic circulatory arrest. Results . The sequence of neurophysiologic events during rewarming did not mirror the events during cooling. The evoked potentials recovered first followed by EEG burst-suppression and then continuous EEG. The time to recovery of the evoked potentials N20-P22 complex was significantly correlated with the time of circulatory arrest even in patients without postoperative neurologic deficits (r = 0.37, ( p = 0.002). The nasopharyngeal temperatures at which continuous EEG activity and the N20-P22 complex returned were strongly correlated (r = 0.44, p = 0.0002; r=0.41, p = 0.00003) with postoperative neurologic impairment. Specifically, the relative risk for postoperative neurologic impairment increased by a factor of 1.56 (95% CI 1.1 to 2.2) for every degree increase in temperature at which the EEG first became continuous. Conclusions . No trend toward shortened recovery times or improved neurologic outcome was noted with lower temperatures at circulatory arrest, indicating that the process of cooling to electrocerebral silence produced a relatively uniform degree of cerebral protection, independent of the actual nasopharyngeal temperature.