Pulse Pressure Ratio Research Articles

Hybrid Powder‐Based Additive Manufacturing of Laser‐Induced Graphene 3D Architectures with Tunable Porous Microstructures from Waste Sources of Black Liquor and White Pollution

AbstractMacroscopic 3D‐controllable graphene (3D‐CG) architectures not only retain the intrinsic properties of graphene sheets but also exhibit structural advantages for pollutant adsorption and energy storage. This paper proposes a novel hybrid powder‐based additive manufacturing method to fabricate 3D biomass‐derived laser‐induced graphene (3D B‐LIG) structures with customizable geometries and microporous features. This method utilizes two waste sources as feedstock precursors for sustainable graphene production: “black liquor” (sodium lignosulfonate, NaLS) and “white pollution” (polypropylene, PP). Employing a computer‐aided design process, this method allows for the synchronous creation of various freeform macrostructures, with either identical or variable sections. To optimize the formability and processing efficiency of 3D B‐LIG, systematic studies have been conducted. These studies establish the relationship between processing parameters and the resulting structures by controlling the laser parameters and the mixing ratio of NaLS and PP. By leveraging tunable microporous structures with a maximized specific surface area of 485.3 m2 g−1, 3D B‐LIG demonstrates exceptional performance in pollutant adsorption (with a maximum adsorption capacity of 283.3 mg g−1 for methylene blue) and energy storage (with a gravimetric specific capacitance value of 194.9 F g−1).

Health Care Resource Use and Total Mortality After Hospital Admission for Severe COVID-19 Infections During the Initial Pandemic Wave in France: Descriptive Study.

Little is known about post-hospital health care resource use (HRU) of patients admitted for severe COVID-19, specifically for the care of patients with postacute COVID-19 syndrome (PACS). A list of HRU domains and items potentially related to PACS was defined, and potential PACS-related HRU (PPRH) was compared between the pre- and post-COVID-19 periods, to identify new outpatient care likely related to PACS. A retrospective cohort study was conducted with the French National Health System claims data (SNDS). All patients hospitalized for COVID-19 between February 1, 2020, and June 30, 2020 were described and investigated for 6 months, using discharge date as index date. Patients who died during index stay or within 30 days after discharge were excluded. PPRH was assessed over the 5 months from day 31 after index date to end of follow-up, that is, for the post-COVID-19 period. For each patient, a pre-COVID-19 period was defined that covered the same calendar time in 2019, and pre-COVID-19 PPRH was assessed. Post- or pre- ratios (PP ratios) of the percentage of users were computed with their 95% CIs, and PP ratios>1.2 were considered as "major HRU change." The final study population included 68,822 patients (median age 64.8 years, 47% women, median follow-up duration 179.3 days). Altogether, 23% of the patients admitted due to severe COVID-19 died during the hospital stay or within the 6 months following discharge. A total of 8 HRU domains were selected to study PPRH: medical visits, technical procedures, dispensed medications, biological analyses, oxygen therapy, rehabilitation, rehospitalizations, and nurse visits. PPRs showed novel outpatient care in all domains and in most items, without specificity, with the highest ratios observed for the care of thoracic conditions. Patients hospitalized for severe COVID-19 during the initial pandemic wave had high morbi-mortality. The analysis of HRU domains and items most likely to be related to PACS showed that new care was commonly initiated after discharge but with no specificity, potentially suggesting that any impact of PACS was part of the overall high HRU of this population after hospital discharge. These purely descriptive results need to be completed with methods for controlling for confusion bias through subgroup analyses. ClinicalTrials.gov NCT05073328; https://clinicaltrials.gov/ct2/show/NCT05073328.

An outcome-driven threshold for pulse pressure amplification

Pulse pressure amplification (PPA) is the brachial-to-aortic pulse pressure ratio and decreases with age and cardiovascular risk factors. This individual-participant meta-analysis of population studies aimed to define an outcome-driven threshold for PPA. Incidence rates and standardized multivariable-adjusted hazard ratios (HRs) of cardiovascular and coronary endpoints associated with PPA, as assessed by the SphygmoCor software, were evaluated in the International Database of Central Arterial Properties for Risk Stratification (n = 5608). Model refinement was assessed by the integrated discrimination (IDI) and net reclassification (NRI) improvement. Age ranged from 30 to 96 years (median 53.6). Over 4.1 years (median), 255 and 109 participants experienced a cardiovascular or coronary endpoint. In a randomly defined discovery subset of 3945 individuals, the rounded risk-carrying PPA thresholds converged at 1.3. The HRs for cardiovascular and coronary endpoints contrasting PPA < 1.3 vs ≥1.3 were 1.54 (95% confidence interval [CI]: 1.00–2.36) and 2.45 (CI: 1.20–5.01), respectively. Models were well calibrated, findings were replicated in the remaining 1663 individuals analyzed as test dataset, and NRI was significant for both endpoints. The HRs associating cardiovascular and coronary endpoints per PPA threshold in individuals <60 vs ≥60 years were 3.86 vs 1.19 and 6.21 vs 1.77, respectively. The proportion of high-risk women (PPA < 1.3) was higher at younger age (<60 vs ≥60 years: 67.7% vs 61.5%; P < 0.001). In conclusion, over and beyond common risk factors, a brachial-to-central PP ratio of <1.3 is a forerunner of cardiovascular coronary complications and is an underestimated risk factor in women aged 30–60 years. Our study supports pulse wave analysis for risk stratification.

Improving the electrical conductivity of multiwalled carbon nanotubes‐containing micromoldings via in situ construction of electrically conductive networks

AbstractMicroinjection molding (μIM) is characterized by high shearing and cooling rates, resulting in higher a degree of filler orientation which impairs the electrical conductivity (σ) of conductive filler‐containing polymer composites when compared with that of compression molding and conventional injection molding processes. In this study, polypropylene/polyamide 6/multiwalled carbon nanotubes (PP/PA6/CNT) composites were used as the model system to investigate how blending sequence, injection speed, and component mass ratios affected the morphology and σ of PP/PA6/CNT microparts. The results demonstrated that CNTs exhibited a higher affinity for the polar PA6 phase and they tended to be preferentially distributed in PA6 domains. The deformation and coalescence of CNT‐rich PA6 phase promoted the creation of an intact and continuous filler network structure along the flow direction under the influence of high shearing conditions in μIM. When the mass ratio of PP:PA6 was 70:30 and the concentration of CNT was 7 wt%, the micropart possessed the highest σ (1.2 × 10−6 S/m) when compared with their PP/CNT (4.4 × 10−9 S/m) and PA6/CNT (3.4 × 10−10 S/m) counterparts. Higher injection speeds resulted in higher degree of CNT orientation, which negatively affected the σ of subsequent moldings. This work established an approach for producing electrically conductive microparts that demonstrate promising applications in the fields of electronics, automotive, and microsystems among others.Highlights PP/PA6/CNT composites were used as model systems for microinjection molding. The electrical conductivity was improved by shear‐induced deformation of CNT‐rich phase. The properties of PP/PA6/CNT microparts were affected by process parameters.

Role of hemolysis on pulmonary arterial compliance and right ventricular systolic function after cardiopulmonary bypass

BackgroundCardiopulmonary bypass (CPB) is associated with intravascular hemolysis which depletes endogenous nitric oxide (NO). The impact of hemolysis on pulmonary arterial compliance (PAC) and right ventricular systolic function has not been explored yet. We hypothesized that decreased NO availability is associated with worse PAC and right ventricular systolic function after CPB. MethodsThis is a secondary analysis of an observational cohort study in patients undergoing cardiac surgery with CPB at Massachusetts General Hospital, USA (2014–2015). We assessed PAC (stroke volume/pulmonary artery pulse pressure ratio), and right ventricular function index (RVFI) (systolic pulmonary arterial pressure/cardiac output), as well as NO consumption at 15 min, 4 h and 12 h after CPB. Patients were stratified by CPB duration. Further, we assessed the association between changes in NO consumption with PAC and RVFI between 15min and 4 h after CPB. ResultsPAC was lowest at 15min after CPB and improved over time (n = 50). RVFI was highest -worse right ventricular function- at CPB end and gradually decreased. Changes in hemolysis, PAC and RVFI differed over time by CPB duration. PAC inversely correlated with total pulmonary resistance (TPR). TPR and PAC positively and negatively correlated with RVFI, respectively. NO consumption between 15min and 4 h after CPB correlated with changes in PAC (−0.28 ml/mmHg, 95%CI −0.49 to −0.01, p = 0.012) and RVFI (0.14 mmHg*L−1*min, 95%CI 0.10 to 0.18, p < 0.001) after multivariable adjustments. ConclusionPAC and RVFI are worse at CPB end and improve over time. Depletion of endogenous NO may contribute to explain changes in PAC and RVFI after CPB.

Fabrication of -SO3H-functionalized polyphosphazene-reinforced proton conductive matrix-mixed membranes.

Proton exchange membranes (PEMs) have emerged as very promising membranes for automotive applications because of their notable proton conductivity at low temperatures. These membranes find extensive utilization in fuel cells. Several polymeric materials have been used, but their application is constrained by their expense and intricate synthetic processes. Affordable and efficient synthetic methods for polymeric materials are necessary for the widespread commercial use of PEM technology. The polymeric combination of hexachlorocyclotriphosphazene (HCCP) and 4,4-diamino-2,2-biphenyldisulfonic acid facilitated the synthesis of PP-(PhSO3H)2, a polyphosphazene with built-in -SO3H moieties. Characterization revealed that it was a porous organic polymer with high stability. PP-(PhSO3H)2 exhibited a proton conductivity of up to 8.24 × 10-2 S cm-1 (SD = ±0.031) at 353 K under 98% relative humidity (RH), which was more than two orders of magnitude higher than that of its -SO3H-free analogue, PP-(Ph)2 (2.32 × 10-4 S cm-1) (SD = ±0.019) under identical conditions. Therefore, for application in a PEM fuel cell, PP-(PhSO3H)2-based matrix-mixed membranes (PP-(PhSO3H)2-MMMs) were fabricated by mixing them with polyacrylonitrile (PAN) in various ratios. The proton conductivity could reach up to 6.11 × 10-2 S cm-1 (SD = ±0.0048) at 353 K and 98%RH, when the weight ratio of PP-(PhSO3H)2 : PAN was 3 : 1, the value of which was comparable with those of commercially available electrolytes used in PEM fuel cells. PP-(PhSO3H)2-MMM (3 : 1) had an extended lifetime of reusability. Using phosphazene and bisulfonated multiple-amine modules as precursors, we demonstrated that a porous organic polymer with a highly effective proton-conductive matrix-mixed membrane for PEM fuel cells could be produced readily by an intuitive polymeric reaction.

Purpurin intercalated layered double hydroxide nanocomposites for improved CO2 visible photocatalytic reduction: Dye-intercalation stabilization and sensitization

Purpurin(pp) can be used as a photosensitive molecule in photocatalytic systems due to its excellent absorption of visible light, but its application is limited due to its poor stability under light. Layered double hydroxides (LDHs) can act as molecular containers due to their interlayer anion exchangeability, introducing target anions into the interlayer of LDHs and improving the instability of anions by utilizing the 2D confinement environment between LDHs layers. A series of co-intercalation materials with different ratios of pp and dodecyl sulfonate (SDS) were prepared through the hydrothermal method in this work, denoted as SDS-pp(x%)/LDHs. Compared with pp, the absorbance retention rate of SDS-pp(x%)/LDHs increased from 12.5% to 90% after 5 h of light exposure. Then its potential application in visible photocatalytic reduction of CO2 was explored. When the intercalation ratio of pp is 3%, the performance is optimal. Compared with ZnAl LDHs, the yield of CO produced by SDS-pp(3%)/LDHs was increased by 12 times and a small amount of 8-electron reduction product CH4 appeared. Through mechanism exploration, the matching energy level relationship between pp and LDHs promotes electron transfer from pp to LDHs. In addition, the catalyst exhibits good cyclic photocatalytic reduction performance for CO2 due to its stable intercalation structure.

Hemodynamic and Management Perspectives in Heart Failure Patients

Introduction Prevalence of heart failure (HF) is increasing, and right ventricular (RV) dysfunction is an independent predictor of mortality. Accurate echocardiographic evaluation of RV function is challenging and novel parameters which can aid in prediction RV function are required. Pulmonary artery Pulsatility index (PAPi) is one such parameter. Patients and Methods We conducted a prospective study in 33 patients admitted with symptoms of HF and severe LV dysfunction (EF &lt; 35) who underwent right heart catheterization and followed them for 6 months. Primary objective was to determine the association of PAPi with hospitalizations and mortality in short-term follow-up in HF patients. Clinical, demographic, echocardiographic, and catheterization data were recorded. PAPi was calculated as a ratio of pulmonary artery pulse pressure and right atrial pressure. Results The mean age of population was 47 years (±12). Males were 20(61%) and females were 13(39%). Median PAPi in the study population was 2.42 (IQR-1.83). The study population were stratified into 3 groups based on 10th, 50th, and 90th percentile PAPi and on comparisons between groups PAPi was significantly associated with hospitalization at 1 and 6 months in univariate ( P = .03 and P = .03 respectively) and in multivariate analysis ( P = .04). PAPi was not found to be associated with mortality at 1 month or 6 months. However, the absolute mortality was low in the study population (n = 4). Conclusion PAPi has been found to be a strong and an independent predictor of hospitalization at 1 month and 6 months. Comments Advanced HF is seen in 1 out of 5 patients with HF. It is characterized by refractory symptoms, multiple hospitalizations, fluid retention, elevated natriuretic peptides, and decreased cardiac output often requiring inotropes. The survival rate is poor. The presence of right ventricular dysfunction is an independent predictor of mortality in these patients. Hemodynamic assessment is of importance in these patients to guide regarding further management, ie, use of inotropes, left ventricular assist devices, etc. The PAPi is a marker derived from the formula (PASP-PADP/RAP). 1 The outcome worsens as the PAPi decreases. However, the stroke volume, pulmonary artery capacitance (PAC), and right atrial pressure all have an impact on PAPi. Patients with high PAC will have better PAPi compared to those with low PAC with the stroke volume being constant. 2 Different subsets of HF population have varying PAPI thresholds, with isolated RV infarction having the lowest (0.9) and severe HF having the highest (3.2). 2 Future research should examine the impact of exercise, inotropes, and vasodilators.

Search for single production of vector-like top partner T → H+b and [formula omitted] at the LHC Run-III

While experimental data has not ruled out the possibility of additional Higgs bosons or gauge sectors, several alternative models have been proposed to go beyond the standard model and tackle the question of hierarchy. These models predict the existence of heavy vector-like partner quarks that exhibit vector-axial (V-A) coupling, typically on the TeV scale. In this work, we use simplified interactions to establish the fundamental components of the model and explore potential scenarios beyond the standard model. We focus on the unusual decays of the partner heavy quark, called T, into H±b, which may compete with W±b decays and create a new discovery channel at the Large Hadron Collider (LHC). Using Monte Carlo (MC) simulations, we analyze the signal-to-noise ratio of pp→qg→T+bb¯j→H+bb¯j→W+bb¯j→1ℓ+4b+1j+E̸T, and evaluate the sensitivity of the LHC to the masses of T and H± in the two-Higgs-doublet model (2HDM) plus the vector-like quark (VLQ) model with a branching ratio of 100% for T→H±b. We take into account current and predicted luminosities, as well as theoretical and experimental bounds. This paper presents a new strategy for identifying VLQs at the LHC, which goes beyond the usual search strategies that rely on decays of T into Standard Model bosons.

Factors associated with arterial stiffness assessed by pulse pressure amplification in healthy children and adolescents: a cross-sectional study

BackgroundIncreasing evidence suggests that reducing pulse pressure amplification (PPA) plays an important role in pathogenesis and progression of cardiovascular disease. This is a cross-sectional, observational, and analytical study in which we evaluated the associated factors with a greater chance of reducing PPA in 136 healthy children and adolescents aged 8 to 19 years old stratified by gender and age group.MethodsArterial stiffness and vascular and hemodynamic parameters were non-invasively measured using Mobil-O-Graph® (IEM, Stolberg, Germany), a cuff-based oscillometric device. PPA was expressed as the peripheral-to-central pulse pressure ratio (PPp / PPc). Participants with PPA < 1.49 were considered as part of the arterial stiffness group.ResultsIn a univariate model, the increase in total vascular resistance, the reflection coefficient and the augmentation pressure were more likely to have arterial stiffness in all groups. The factors most likely to have arterial stiffness (as assessed by the reduction of the PPA) in the multivariate model were increasing age, the reflection coefficient and cardiac index in the total sample, male group and child and adolescent groups. In addition to age in the female group, cardiac output, stroke volume, and AIx@75 were the factors most likely to present arterial stiffness.ConclusionsThe results show for the first time in children and adolescents that the factors most likely to reduce PPA are related to the reflection wave, which determines aortic pressures and, therefore, left ventricular afterload.

Construction of antifouling zwitterionic coatings on polypropylene microporous membranes via N-hydroxyphthalimide(NHPI) catalysis

Developing polyolefin microporous membranes with good antifouling ability and high separation efficiency is an important and urgent work. Herein, polypropylene microporous membranes (PP (mm)) containing zwitterionic polymer was prepared by grafting poly (sulfobetaine methacrylate) (PSBMA) onto the membrane via N-hydroxyphthalimide(NHPI) catalysis and activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP) for the first time. The structure, morphology, hydrophilicity and antifouling ability of PP (mm)-g-PSBMA was systematically studied. Water contact angle of the modified membrane could be sharply reduced at a proper grafting degree (GD), and it exhibited extraordinary hydrophilicity. The PP (mm)-g-PSBMA membrane also showed excellent protein antifouling ability and higher water flux compared to that of pristine PP membrane. Flux recovery ratio (FRR) of PP (mm)-g-PSBMA was increased to 93.1 % and relative flux reduction ratio (RFR) was decreased to 25.3%. This work presents a controllable and high efficiency strategy to polyolefin separation membrane for high value products.

Proportional pulmonary pulse pressure: A new index to assess response to veno-arterial extracorporeal membrane oxygenation.

Based on theoretical physiology, the ratio of pulmonary artery pulse pressure to mean pulmonary pressure (PP-MPAP), termed proportional pulmonary pulse pressure, provides a measure of coupling between the right ventricle and the pulmonary circulation. This study tested the hypothesis that lower PP-MPAP ratio was associated with left ventricular (LV) distension in patients with cardiogenic shock who underwent extracorporeal life support (ECLS). This is a retrospective observational single-centre study of 22 patients with cardiogenic shock who underwent ECLS as the primary support modality without and with LV distension and Impella unloading. The relationship between post-support PP-MPAP and 12-hour lactate clearance was also assessed. Of the 22 patients: 10 patients underwent additional Impella unloading due to LV distension (Group 1) and 12 patients on ECLS only without LV distension (Group 2). As predicted by the theoretical model, PP-MPAP on ECLS dropped in Group 1 (pre-Impella) from 0.473 ± 0.067 to 0.372 ± 0.087, p < 0.001; but increased in Group 2 patients without LV distension (0.518 ± 0.070 to 0.549 ± 0.072, p = 0.002). Impella support in Group 1 increased PP-MPAP (0.372 ± 0.087 to 0.615 ± 0.094, p < 0.001). On multiple regression analysis, post-support PP-MPAP was significantly associated with 12-hour lactate clearance. Changes in PP-MPAP is associated hemodynamic response to ECLS and 12-hour lactate clearance. This simple parameter may guide therapeutic optimization in cardiogenic shock and ECLS.

Characterization of Biodegradable Composites from Polypropylene, Polypropylene Grafted Maleic Anhydride, and Durian Seed Starch

The characterization of biodegradable composite from durian seed starch that is mixed polypropylene, and polypropylene grafted maleic anhydride has been done. The stages of this preparation were, the first had prepared durian seed starch, the second had the process of grafting maleic anhydride into polypropylene and the third had made of composite with the composition of PP:PP-g-MA: DSS (7:0.5:0.2); (7:0.5:0.3); (7:0.5:0.4); (7:0.5:0.5); (7:0.5:0.6) (w/w). The biodegradable composites obtained were characterized by tensile strength, surface morphology analysis by SEM, differential thermal analysis (DTA), analysis in nature with the ability to decompose biodegradable test, and functional groups analysis by FTIR spectroscopy. The results showed that the biodegradable composites have the best properties in the ratio of PP:PP-g-MA: DSS was (7:0.5:0.5) (w/w) with the test results of tensile stress is 12.556 N/m2, and the elongation is 8.600%, the images on a few flat surfaces and improved homogeneity, temperature change, and strong group interactions as well as having good biodegradable properties.

Fabrication of Biodegraded Composite from Polypropylene, Polypropylene Grafted Maleic Anhydride, and Chempedak Seed (Artocarpus integer) Starch

Fabrication of biodegraded composite from polypropylene, polypropylene grafted maleic anhydride, and chempedak seed (Artocarpus integer) starch has been conducted. The stages were prepared starch of Cempedak seed, grafting process of maleic anhydride on polypropylene, and fabrication of composite with a composition ratio of PP: PP-g-MA: starch of chempedak seed (9.5:0.5:0.1)g, (9.5:0.5:0.2)g, (9.5:0.5:0.3)g, (9.5:0.5:0.4)g, (9.5:0.5:0.5) g, and PP: starch of chempedak seed (10:2)g. The composites obtained were characterized using tensile strength and elongation testing, surface morphology analysis by SEM, analysis in nature with the ability to decompose by biodegradable test, and functional groups analysis by FTIR spectroscopy. The results showed that the biodegradable composites have the best properties in the ratio of PP: PP-g-MA: starch of chempedak seed (9.5:0.5:0.1)g with the test results of tensile strength was 28.743 N/m2, and also the SEM results show that flat surface and improved homogeneity, and strong group interactions as well as having good biodegradable properties.

Glass/polypropylene hybrid knitted fabrics for toughening of thermoset composites

This paper investigates tensile, flexural, impact and compression after impact (CAI) performance of weft knitted fabric reinforced thermoset composites containing glass/polypropylene (PP) hybrid yarns. Glass and PP yarns were combined at three different PP ratios and converted to supreme hybrid knitted structures using a circular knitting machine. Using PP yarns helped to decrease glass fibre breakages during the knitting process. It was observed that the addition of PP yarns decreased overall density of composites up to 22%. Fabric tensile test indicated that using PP yarns enhanced ductility of the knitted fabrics. Flexural strength of composites was decreased by addition of PP yarns for both wale and course direction at 3 and 4-point bending tests. However, hybrid composites had higher specific flexural strength when they all had same glass fibre volume fraction for 3-point bending strength. Similar results were achieved for tensile properties whilst hybrid composites had higher values after normalising the same fibre volume fractions. Impact and CAI test results exhibited that the addition of PP yarns enhanced impact and damage tolerance of composites as well as reducing impact induced areas.

Bacterial Metabolic Response to Change in Phytoplankton Communities and Resultant Effects on Carbon Cycles in the Amundsen Sea Polynya, Antarctica

We investigated changes in heterotrophic bacterial metabolic activities and associated carbon cycles in response to a change in dominant phytoplankton communities during two contrasting environmental conditions in austral summer in the Amundsen Sea polynya (ASP), Antarctica: the closed polynya condition in 2014 (ANA04) and the open polynya condition in 2016 (ANA06). In ANA04, Phaeocystis antarctica predominated phytoplankton biomass, comprising 78% of total phytoplankton carbon biomass, whereas diatoms and Dictyocha speculum accounted for 45% and 48% of total phytoplankton carbon biomass, respectively, in ANA06. Bacterial production (BP) showed a significant positive correlation with only chlorophyll-a (Chl-a, rho = 0.66, p &amp;lt; 0.001) in P. antarctica-dominated ANA04, whereas there were significant positive relationships of BP with various organic carbon pools, such as chromophoric dissolved organic matter (CDOM, rho = 0.84, p &amp;lt; 0.001), Chl-a (rho = 0.59, p &amp;lt; 0.001), and dissolved organic carbon (DOC, rho = 0.51, p = 0.001), in ANA06 when diatoms and D. speculum co-dominated. These results indicate that BP depended more on DOC directly released from P. antarctica in ANA04, but was supported by DOC derived from various food web processes in the diatom-dominated system in ANA06. The BP to primary production (BP : PP) ratio was three-fold higher in P. antarctica-dominated ANA04 (BP: PP = 0.09), than in diatom- and D. speculum-co-dominated ANA06 (BP : PP = 0.03). These results suggested that the microbial loop is more significant in Phaeocystis-dominated conditions than in diatom-dominated conditions. In addition, the decreases in BP : PP ratio and bacterial respiration with increasing diatom proportion in the surface mixed layer indicated that the change from P. antarctica to diatom predominance enhanced biological carbon pump function by increasing particulate organic carbon export efficiency. Consequently, our results suggest that bacterial metabolic response to shifts in phytoplankton communities could ultimately affect larger-scale ecological and biogeochemical processes in the water column of the ASP.

CORRELATION OF BLOOD PRESSURE CHANGES WITH THE FUNCTIONAL CAPACITY IN HEART FAILURE PATIENTS WITH PRESERVED AND MID-RANGE EJECTION FRACTION

Objective: 6-minute walk test (6-MWT) reflects the daily activity of heart failure (HF) patients who develop progressive limitation of functional capacity (FC). Our aim was to assess different blood pressure (BP) parameters and their changes after 6-MWT in patients with HF with mid-range ejection fraction (EF) (HFmEF) and HF with preserved EF (HFpEF) and correlate them with the FC assessed by 6-minute walk distance (6-MWD). Design and method: Patients presented with clinical manifestations of HF were admitted to Cardiology Department and medically stabilized. 40 HFmEF patients and 50 HFpEF patients underwent 6-MWT according to the American Thoracic Society guidelines 2002. Different BP parameters before and after 6-MWT were recorded including systolic blood pressure, diastolic blood pressure (DBP), mean BP, pulse pressure (PP), and proportionate pulse pressure (PPP) defined as the ratio of PP and SBP. Limited FC was defined as 6-MWD &lt; 300 M. Abnormal BP response to exercise (ABPRE) was defined as a decrease, no increase or an increase of the SBP after exercise by &lt; 20 MMHG. Results: The mean 6-MWD was 325.3 ± 56.84 meters (M), 316.1 ± 61.33 M, 332.66 ± 52.44 M in all patients, HFmEF patients, and HFpEF patients respectively. 6-MWD and limited FC showed no significant difference between the 2 groups. Limited FC affected 42.5 % and 33 % of HFmEF and HFpEF patients respectively. ABPRE affected 28 (31.1 %) of patients and was significantly higher in HFmEF than HFpEF patients. Independent predictors of limited FC were lower EF, PP and PPP and higher DBP in HFmEF patients and lower EF in HFpEF patients. Cut-off points for prediction of limited included PP &lt; 32.5 MMHG and PPP &lt; 30.22 % in HFmEF patients, PP &lt; 37.5 MMHG and PPP &lt; 32.67 % in HFpEF patients, and EF &lt; 42.5 % in all patients (figure 1). Conclusions: The 6-MWT is well tolerated by HF patients and easy to perform in clinical practice. Simple bed-side measurement of BP parameters correlated with the FC and predicted limited FC in HFmEF and HFpEF patients.

VASCULAR BIOMARKERS IN RELATION TO INDICES OF AORTIC STIFFNESS AND RENAL FUNCTION IN PRIMARY HYPERTENSION

Objective: Degradation of the glycocalyx (GC), the innermost layer protecting the vascular endothelium, and up-regulation of adhesion molecules is associated with subclinical atherosclerosis and endothelial dysfunction, while aortic stiffness is related to early structural vascular changes and decline in renal function. However, few studies have investigated vascular biomarkers in relation to central and peripheral hemodynamics, and renal function in hypertension. Design and method: 107 patients (58 ± 13 years) with hypertension (mean 149/87 mmHg; 31% on antihypertensive treatment) and a wide range of renal function (eGFR 130 to 21 ml/min x 1.73 m2, mean 74 ml/min), were investigated. Indices of aortic stiffness were central systolic blood pressure (cSBP), central pulse pressure (cPP), carotid/brachial pulse pressure ratio (cPP/brPP), augmentation index (AIx), carotid-femoral pulse wave velocity (PWV), and aortic-brachial PWV ratio, assessed by applanation tonometry (SphygmoCor, AtCor Medical). Endothelial function was studied by forearm post-ischemic flow mediated vasodilatation. The GC glycoproteins hyaluronan (HA) and syndecan-1 (Syn-1), and adhesion molecules (ICAM-1, VCAM-1, and E-selectin), were analysed with ELISA. Results: Median[range] HA, Syn-1, ICAM-1, VCAM-1, and E-selectin were 15 [11–20], 38[27–54], 302[264–345], 347[304–408], and 32[26–41] ng/mL, respectively. HA was related to cPP (r = 0.31; P = 0.002), cPP/brPP (r = 0.21; P = 0.002), AIx (r = 0.21; P = 0.034), PWV (r = 0.31; P = 0.003), and aortic-brachial PWV ratio (r = 0.27; P = 0.011). Syn-1 was inversely related to cSBP (r = –0.17; P = 0.043). E-selectin tended to be inversely related to cSBP (p = 0.10) and to cPP (p = 0.071). HA and VCAM-1 were inversely related to eGFR (r = –0.45 and r = –0.43; both P &lt; 0.001). All vascular biomarkers were unrelated to flow-mediated vasodilation. Conclusions: Vascular biomarkers were associated with indices of aortic stiffness, and impaired renal function, but was unrelated to peripheral endothelial function. HA showed association with increased stiffness, compared to Syn-1 that was unrelated to stiffness, and both HA and VCAM-1 were inversely related to renal function, where elevation of HA and VCAM-1 may reflect endothelial dysfunction of the kidneys. Thus, our results suggest that functional vascular biomarkers may relate to early structural and functional vascular changes in uncomplicated hypertension with impaired renal function.

Elastic Reverse Time Migration for Weakly Illuminated Structure

One of the most effective techniques to obtain PP and PS images is elastic reverse time migration which employs multi-component seismic data. The two types of complementary images play an important role in reducing blind spots in seismic exploration. However, the migration image of deep structures is always blurred due to the shielding effect of overburden rock on seismic waves. To overcome this issue, we develop an elastic reverse time migration approach for insufficient illumination. This approach contains two crucial elements. The first is that we derive an elastic wave equation to extract the wavefields associated with the exploration target using the staining algorithm. Secondly, we develop an inner product imaging condition with a filter to mute migrated artifacts. The filter, consisting of two vectors, determines which part of the wavefield is contributed to imaging. Synthetic examples exhibit that the proposed elastic reverse time migration method can improve the signal-to-noise ratio of PP and PS images of weakly illuminated structures.

Proportional Pulmonary Artery Pulse Pressure Identifies Hemodynamic Response to Impella: Conceptualization and Clinical Validation

<h3>Purpose</h3> <b>1.</b> To describe the physiologic determinants of proportional pulmonary artery pulse pressure (= ratio of pulmonary pulse pressure to mean pulmonary pressure, PP-MPAP) <b>2.</b> clinical application of PP-MPAP in patients with cardiogenic shock (CS) who underwent left-sided Impella support. <h3>Methods</h3> <b>1.</b> Using established physiologic concepts and prior data, the change in PP-MPAP a was modelled over a range of hemodynamic parameters (Matlab, Mathworks). <b>2.</b> 16 patients with CS who underwent Impella support were included. Hemodynamic responder was defined as increase in cardiac power output index (CPOi)>20%. Clinical endpoint was lactate clearance 12 hours after Impella support. <h3>Results</h3> <b>1.</b> The relationship between stroke volume at different heart rates and PAWP was modelled [FIGURE]. <b>2.</b> 16 patients were included (age: 50±7 years; 13/16 males; 9/16 acute MI; 7/16 cardiomyopathy; LVEF: 17±4%). Impella reduced PAWP in all patients, but only 6/16 patients were responders. As predicted by the model, PP-MPAP increased in responders but dropped in non-responders. The increase in PP-MPAP correlated with increase in CPOi. The 10 non-responders were escalated to Ecpella (3(2-5)hours post-Impella), which increased PP-MPAP [TABLE]. 12-hour lactate clearance was greater in responders despite escalation to Ecpella in non-responders. Post-support PP-MPAP and the change in PP-MPAP were significantly associated with 12-hour lactate clearance. <h3>Conclusion</h3> PP-MPAP has a predictable relationship with stroke volume, and can identify hemodynamic responders to Impella, who had higher 12-hour lactate clearance.