Strong Negative Linear Correlation Research Articles

Two-Body Abrasive Wear Behavior and Its Correlation With Mechanical Properties of Aged AA6063 Alloy

Abstract This study aims to correlate the abrasive wear performance with mechanical properties, considering AA6063 Al–Mg–Si alloy as the model material. The selected alloy specimens are subjected to artificial ageing at 150 °C for an ageing duration ranging from 1 to 672 h, covering severely under-aged (SUA) to peak-aged (PA) to severely over-aged (SOA) states. Apart from the hardness and tensile properties, two-body abrasive wear properties are also evaluated for differently aged alloys in terms of wear-rate, coefficient of friction, and roughness of the abraded surfaces. Furthermore, the generated wear debris, surface, and subsurface of the abraded specimens are critically examined to reveal the micro-mechanisms of abrasion. The lowest amount of wear-rate is observed for a PA alloy with maximum hardness, while the OA alloy exhibits a slightly lower wear-rate than the UA alloy at a similar level of hardness. Statistical analyses of wear-rate and various mechanical properties of all heat-treated alloys establish a strong negative linear correlation between the wear-rate and hardness, yield strength, tensile strength, and strength coefficient, whereas a positive linear correlation with the strain hardening exponent. Relationships between wear-rate and different roughness parameters are also discussed. Under the investigated wear condition, the aged alloys endure significant plastic deformation; micro-plowing, micro-cutting, and delamination are found to be the predominant mechanisms during abrasion.

Mineralogical and Geochemistry Study of Darnah Formation in Wadi Al Kharsha, Northeast Libya

This paper has been carried out to determine the mineralogical and geochemical characteristics of Eocene Darnah limestone which outcrops at Wadi Al Kharsha as an example of the Darnah Formation. The most conspicuous phenomenon is the upward increase of the dolomitization process, whereas, the dolomite content ranges from 4.34 to 15.48 % with an average value of 8.99%. The lime (CaO) represents the major predominant with a high content (48.08%), it can be blend with other carbonates to improve its quality to meet the specifications of raw material for cement manufacture. The relationship between calcium (CaO) and magnesium (MgO) exhibits a significantly strong negative linear correlation coefficient (R2 = 0.967), which emphasizes the dolomitization process, while the relationship between SiO2 and Al2O3 is a positive linear significant relationship with a strong correlation coefficient (R2 = 0.98), whereas, the SiO2 increases with increasing of Al2O3. The calculated mineralogical composition revealed that halite, gypsum, and hematite are considered to be minor constituents, almost less than 1.0%. Keywords: Limestone; Darnah Formation; Mineralogy; Geochemistry; Dolomitization; Characterizations; Cement

The relationship between glycosylated hemoglobin, time-in-range and glycemic variability in type 1 diabetes patients under flash glucose monitoring

ObjectivesFlash glucose monitoring in patients with type 1 diabetes provides new glucometric data that allow for the assessment of glycemic control beyond HbA1c. The objective of the study was to evaluate the relationship between HbA1c, time-in-range (TIR) and glycemic variability in a cohort of paediatric and adult patients with type 1 diabetes and treatment with flash glucose monitoring. Material and methodsThis was a cross-sectional study in 195 patients with type 1 diabetes (42.6% females, 70 paediatric, 26.2% continuous subcutaneous insulin infusion, 28.7% coefficient of variation [CV]≤36%) in intensive treatment and flash glucose monitoring. Clinical, analytical and glucometric data were evaluated. ResultsThe relationship between the TIR and HbA1c showed a strong negative linear correlation (R=−0.746; R2=0.557; P<.001), modified in those patients with CV≤36% (R=−0.852; R2=0.836) compared to CV>36% (R=−0.703; R2=0.551). A similar correlation was found when evaluating the TIR and the Glucose Management Indicator (R=−0.846; R2=0.715; P<.001); in patients with CV≤36% (R=−0.980; R2=0.960) versus CV>36% (R=−0.837; R2=0.701); P<.001. Both correlations remained stable in the paediatric population (R=−0.724; R2=0.525; P<.001) and adults (R=−0.706; R2=0.498; P<.001) and by type of treatment: multiple doses of insulin (R=−0.747; R2=0.558; P<.001) and continuous subcutaneous insulin infusion (R=−0.711; R2=0.506; P<.001). In a multiple regression analysis evaluating HbA1c as dependent variable, the only parameters that maintained statistical significance were the TIR (β=−0,031; P<.001), CV (β=0.843; P<.05) and TIR-CV interaction (β=−0.017; P<.01). ConclusionsThe glycemic variability defined by the CV modifies the relationship between the TIR and HbA1c/Glucose Management Indicator and should be taken into account when individualising TIR targets, regardless of age or the type of treatment used.

Relationship of particle density and organic content in sieve fractions of road-deposited sediments from varying traffic sites based on a novel data set

Pollutants (e.g. heavy metals) are to a large extent bound to particles in runoff from traffic areas. Sedimentation is the prevailing process of treatment in most cases. The effectiveness of treatment depends largely on the characteristics of the particles, especially their size and density. Road-deposited sediments (RDS) are the main source of solids in runoff. The sizes and density vary over a wide range, as the particles are composed of mineral and organic components of different origin (e.g. tire and road wear, plant debris, erosion from surrounding areas, atmospheric deposition). While many previous studies have dealt with particle-size distributions, there are still relatively few studies on density. The aim of this study was to investigate the relationship between particle size, organic content and density in RDS on a large data set from different sites and the influence of site-specific conditions on the composition. In addition, it should be checked whether the loss on ignition (LOI) is suitable as a surrogate parameter for density. Density was obtained by gas pycnometry, LOI by ignition in a muffle furnace at 550 °C. In total, 85 RDS samples were collected at 11 sites over a 5 year period and sieved into ten sieve fractions <2000 μm. Each sieve fraction was analyzed for LOI and density (n = 848). This novel data set covers a wide range of boundary conditions in terms of traffic intensity and surrounding vegetation. The results show that there is a strong negative linear correlation of density and LOI independent of particle size <2000 μm (R2 = 0.867). LOI is an applicable surrogate parameter for density in RDS. Site-specifically traffic and vegetation proved significant sources of organic content and density in the multicomponent mixtures in form of tire wear and plant debris.

A single-center retrospective comparison of Duplex ultrasonography versus audible Doppler regarding anterolateral thigh perforator flap harvest and operative times.

We reported on the superiority of preoperative Duplex mapping ("Duplex") over audible Dopplers ("Doppler") in anterolateral thigh perforator (ALT) free flaps for upper extremity reconstruction. To corroborate our findings on a larger cohort, we conducted this present study focusing on surgical efficiency and patient safety. 150 consecutive ALT free flaps were divided into 65 cases of preoperative Duplex versus 85 Doppler controls. We first compared patient demographics, operative details, and defect and flap characteristics. We then assessed group differences in the number and course of perforators pursued intraoperatively, flap harvest and operative times, and donor-site complications. Additionally, the impact of the training level of the primary microsurgeon was evaluated. Cases and controls were comparable regarding age (p= .48), sex (p= .81), ASA class (p= .48), and BMI (p= .90). Duplex was associated with an increased likelihood of raising flaps on one single dominant perforator of purely septal course and significant reductions of flap harvest (68 ± 10min, p< .0001) and operative times (74 ± 16 min, p< .0001), regardless of the experience of the primary microsurgeon. There were strong negative linear correlations between preoperative Duplex and both the flap harvest and operative times (p< .0001). Additionally, while there was no effect on the emergency take-back rate (OR=1.3, p= .60), revisions were significantly less likely among duplexed patients (OR=0.15, p= .04). Preoperative Duplex is associated with a significant reduction in ALT free flap harvest and overall operative times, as well as donor-site revisions as opposed to Doppler planning, regardless of the training level of the primary microsurgeon.

Impaired left atrial strain in the presence of interatrial block in patients with type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases, and is a risk factor for atrial cardiomyopathy. Interatrial block (IAB), as a predictor of AF, is correlated with the extent of LA fibrosis in the process of atrial cardiomyopathy. We have not encountered any study evaluating LA and LV functions with 3D-STE in the presence of IAB in the T2DM patients. The purpose of the present study was to compare the LA and LV myocardial functions in patients with T2DM with and without IAB by 3D-STE. A total of 175 consecutive patients with T2DM who were examined at outpatient clinics were enrolled in the study (85 patients with IAB and 90 patients without IAB). Surface 12-lead standard electrocardiograms (ECGs) were recorded. Clinical characteristics and laboratory values of the patients were obtained. Conventional 2D echocardiographic and 3D-STE analyses were performed. The mean age of the patients was 59 ± 8.7 years, and 112 (64%) of the patients were female. The LAS-r and LAS-active were significantly decreased in the IAB (+) group than in the IAB (-) group. Statistically significant strong negative linear correlations were observed between P-wave duration and 3D-LA strain values. Our results indicate that there is an impairment in LA myocardial dynamics in the presence of IAB in T2DM patients. According to these findings, we can say that it will be useful to evaluate the LA functions at the preclinical stage in the presence of IAB in patients with T2DM, when considering ischemic cardiovascular and cerebral events.

ICAM-1 orchestrates the abscopal effect of tumor radiotherapy

Compelling evidence indicates that radiotherapy (RT) has a systemic inhibitory effect on nonirradiated lesions (abscopal effect) in addition to the ablation of irradiated tumors. However, this effect occurs only in rare circumstances in clinical practice, and mechanisms underlying the abscopal effect of RT are neither fully understood nor therapeutically utilized. Here we identified that intercellular adhesion molecule-1 (ICAM-1), an inducible glycoprotein of the immunoglobulin superfamily, is up-regulated in nonirradiated tumors responsive to RT. ICAM-1 expression in preclinical animal models can be noninvasively detected by optical imaging and positron emission tomography (PET) using near-infrared fluorescence dye- and 64Cu-labeled imaging probes that we synthesized, respectively. Importantly, the expression levels of ICAM-1 determined by quantitative PET imaging showed a strong negative linear correlation with the growth of nonirradiated tumors. Moreover, genetic or pharmacologic up-regulation of ICAM-1 expression by either an intratumoral injection of engineered recombinant adenovirus or systemic administration of a Toll-like receptor 7 agonist-capsulated nanodrug could induce markedly increased abscopal responses to local RT in animal models. Mechanistic investigation revealed that ICAM-1 expression can enhance both the activation and tumor infiltration of CD8+ T cells to improve the responses of the nonirradiated tumors to RT. Together, our findings suggest that noninvasive PET imaging of ICAM-1 expression could be a powerful means to predict the responses of nonirradiated tumors to RT, which could facilitate the exploration of new combination RT strategies for effective ablation of primary and disseminated lesions.

Relación entre hemoglobina glucosilada, tiempo en rango y variabilidad glucémica en una cohorte de pacientes pediátricos y adultos con diabetes tipo 1 con monitorización flash de glucosa

ObjectivesFlash glucose monitoring in patients with type 1 diabetes provides new glucometric data that allow for the assessment of glycemic control beyond HbA1c. The objective of the study was to evaluate the relationship between HbA1c, time-in-range (TIR) and glycemic variability in a cohort of pediatric and adult patients with type 1 diabetes and treatment with flash glucose monitoring. Material and methodsThis was a cross-sectional study in 195 patients with type 1 diabetes (42.6% females, 70 pediatric, 26.2% continuous subcutaneous insulin infusion, 28.7% coefficient of variation [CV]≤36%) in intensive treatment and flash glucose monitoring. Clinical, analytical and glucometric data were evaluated. ResultsThe relationship between the TIR and HbA1c showed a strong negative linear correlation (R=−0.746; R2=0.557; P<.001), modified in those patients with CV≤36% (R=−0.852; R2=0.836) compared to CV>36% (R=−0.703; R2=0.551). A similar correlation was found when evaluating the TIR and the Glucose Management Indicator (R=−0.846; R2=0.715; P<.001); in patients with CV≤36% (R=−0.980; R2=0.960) versus CV>36% (R=−0.837; R2=0.701); P<.001. Both correlations remained stable in the pediatric population (R=−0.724; R2=0.525; P<.001) and adults (R=−0.706; R2=0.498; P<.001) and by type of treatment: multiple doses of insulin (R=−0.747; R2=0.558; P<.001) and continuous subcutaneous insulin infusion (R=−0.711; R2=0.506; P<.001). In a multiple regression analysis evaluating HbA1c as dependent variable, the only parameters that maintained statistical significance were the TIR (β=−0,031; P<.001), CV (β=0,843; P<.05) and TIR-CV interaction (β=−0,017; P<.01). ConclusionsThe glycemic variability defined by the CV modifies the relationship between the TIR and HbA1c/Glucose Management Indicator and should be taken into account when individualizing TIR targets, regardless of age or the type of treatment used.

Enhancement of dielectric properties of Baobab Oil and Mongongo Oil using cost-effective additive for power transformer insulating fluids

Abstract This work aims to determine the applicability of Natural Esters (NE) like Baobab Oil (BAO) and Mongongo Oil (MGO) in power transformers. The dielectric property of Kerosene (KER) is utilized to decrease the viscosity of natural esters to promote better oil circulation in transformer tanks. Kerosene, being non-volatile and a good lubricant, protects alkali metals from oxidation/corrosion and its miscible property is useful as an oil thinner. The blending compositions used here are 1% KER:99% NE, 5% KER:95% NE and 10% KER:90% NE and the blends are subjected to dielectric testing using IEC (International Electrotechnical Commission) and ASTM (American Society for Testing and Materials) standards. Favourable temperature effects are observed with an improvement of 16% in breakdown strength and 61.9% reduction in kinematic viscosity for BAO while an improvement of 24% in breakdown strength and 56.4% reduction in kinematic viscosity are observed for MGO at 10% KER addition without affecting the dielectric performance of NE. In fact, temperature has a strong positive linear correlation with breakdown voltage and an equally strong negative linear correlation with viscosity for natural esters. Based on the results, kerosene is a promising vapour drying additive, and it is therefore recommended as a cost-effective additive to reduce oil viscosity and to minimize the amount of water saturation.

Investigating Math Self-Efficacy and Math Anxiety Regarding Gender, A-Level Math Entry Grade and Mathematics Achievement

Although mathematics is perceived as an indispensable pre-cursor to success in modern society, many students still grapple with a genuine fear of mathematics and feel anxious when engaging in mathematical tasks. One of the affective factors that can affect math anxiety is learners’ belief in their own ability which is termed self-efficacy. In this study we aimed to investigate how math anxiety and math self-efficacy varied across gender, A-level math entry grade and recent mathematics score and how math anxiety and math self-efficacy related in the context of students in Mayuge District, Uganda. We collected data from 60 advanced level (A-level) mathematics students from two secondary schools in Mayuge District. Their study of mathematics was not compulsory but rather by choice. The participants filled a Mathematics Self-Efficacy and Anxiety Questionnaire (MSEAQ). Data were analyzed using descriptive statistics, independent sample t tests, one-way ANOVA, Pearson’s Linear Correlation Coefficient (PLCC) and linear regression. Descriptive statistics indicated a high level of math self-efficacy and a low level of math anxiety among the students. Independent sample t tests revealed no gender differences in math self-efficacy and math anxiety and ANOVA suggested no differences in math self-efficacy and math anxiety for the A-level math entry grades and recent mathematics scores. PLCC revealed a strong significant negative linear correlation between math self-efficacy and math anxiety with r = -0.782. Meanwhile, regression analysis suggested that math self-efficacy explained 60% of math anxiety among A-level students in Mayuge District. A recommendation was made. Keywords : Entry Grade, Gender, Math Achievement, Math Anxiety, Math Self-Efficacy DOI: 10.7176/JEP/11-26-05 Publication date: September 30 th 2020

Association between Natural Killer Cell Cytotoxicity and the Progression of Non-Small Cell Lung Cancer

The present study aims to assess the role of NK-cell in the prognosis of NSCLC. Samples and Methods: A total of sixty newly diagnosed patients with NSCLC were included in this study. Fifteen of them were female and (45) male and then patients were followed up for six months. The diagnosis is revised by the supervisor Oncologist. ELISA technique was used to investigate the two immunological variables (NK & INF-γ). The results show, the mean of NK cell significantly increased from as small as (8.016) among NSCLC cases with an early stage to as high as (14.293) among cases with advanced stages (P =0.001), while in INF-γ test,the quantity of INF-γ was decreased gradually in a mean of (0.13) among metastatic stages of pulmonary cancer compared with an early stage where mean about (0.229); P=0.001. Furthermore, the linear correlation coefficients show there isa strong positive correlation between NK cell very strong positive relationship between the level of NK cell (NKG2A/CD94) and staging (r= 0.608). Meanwhile, strong negative linear correlation coefficients that mean the level of INF-γ decrease with a bad prognosis of NSCLC patients (r= - 0.486). Moreover, by using Kaplan-Mier test the mortality rate of NSCLC patients increased (45% & 59%) with high levels of NK cells concentration respectively during a maximum of six months follow up periods. Meanwhile,the cumulative proportion of deaths in NSCLC patients at six months increased with the lowest tercile of INF-γ (60%). A high expressionof NKG2A/CD94 of CD56bright CD16- in peripheral blood of NSCLC patients correlates with bad prognosis which may be used as the prognostic marker while a high level of INF-γ refers to the good prognosis.Low cytotoxicity of NK correlated with a low level of INF-γ and both of them decreased in concentration after three and six months of follow up post- treatments.

Cyclic behavior and constitutive model of high strength low alloy steel plate

Cyclic loading tests with different protocols were conducted for a high strength low alloy steel. Based on the test results, the low cycle fatigue and extremely low cycle fatigue performance of the high strength steel was discussed and an appropriate constitutive model was established. The experimental results implied that the low and extremely cycle fatigue failure showed different fracture features. For low cycle fatigue, there was a strong negative linear correlation between the fatigue life and the strain amplitude in the log–log scale. However, they did not conform the linear relation when transiting to the low cycle fatigue. The steel represented obvious cyclic softening and good energy dissipation capacity. With the increase of strain amplitude, the softening degree decreased and equivalent damping ratio increased. The cyclic stress–strain curve could be descried by the Ramberg-Osgood model, and the strength coefficient and strain hardening exponent of this steel were larger than those of steel with lower strength. A combined hardening model was calibrated to describe the cyclic plasticity of the steel, and it was verified by the simulation results.

Effect of berberine on in vitro metabolism of sulfonylureas: A herb-drug interactions study.

Berberine and sulfonylureas (glyburide and gliclazide) were co-incubated with rat liver microsomes in the presence of a NADPH-regenerating system. The metabolites of berberine and sulfonylureas were analysed using liquid chromatography with high-resolution mass spectrometry in the positive ion mode. The role of individual isozymes in the metabolism of berberine, glyburide and gliclazide was investigated by using specific inhibitors. In vitro metabolism of berberine led to the formation of demethyleneberberine (B1a) and its isomer B1b through demethylenation. Berberrubine (B2a) and its isomer B2b were formed through demethylation. The isozymes CYP3A and CYP2D were found to be involved in the metabolism of berberine. In vitro metabolism of glyburide and gliclazide led to the formation of hydroxylated metabolites. The isozymes CYP3A and CYP2C were found to be involved in the metabolism of glyburide. Gliclazide was metabolised by CYP2C. In vitro co-incubation of glyburide or gliclazide with berberine showed that each drug's metabolism was compromised as they share a common isozyme. A strong negative linear correlation of glyburide or gliclazide metabolite levels and the concentration of berberine confirmed the effect of berberine on the metabolism of sulfonylureas. The metabolism of sulfonylureas and berberine was affected when these compounds were co-incubated with each other. This may be attributable to competitive binding of the herb and drug to the catalytic sites of the same isozymes.

Volume control of the lower limb with graduated compression during different muscle pump activation conditions and the relation to limb circumference variation

BackgroundThe literature supports the use of graduated compression stockings (GCS) for leg edema. Nevertheless, there is a paucity of data on the GCS effect on limb edema related to sitting, standing, and walking. Data of different limb shapes and their impact on GCS-exerted pressure are lacking. This investigation provides evidence-based information on the effect of GCS on edema reduction and the impact of limb circumference gradients on GCS pressure. MethodsThirty healthy individuals (15 men and 15 women; mean age, 32 ± 5 years) were included. All the participants underwent lower limb volume (Kuhnke formula) measurement, before and after sitting for 30 minutes, wearing below-ankle noncompressive socks. The same assessment was repeated 7 days later, in the same participants, but with wearing of below-knee 16 to 20 mm Hg GCS. At 7-day intervals, 1 week with below-ankle noncompressive socks and 1 week with below-knee 16 to 20 mm Hg GCS, all the participants repeated the same protocol including standing and walking. Ten participants underwent bioimpedance assessment (Biody Xpert II; eBIODY, La Ciotat, France) before and after sitting, standing, and walking. In the same group, B and B1 interface pressure values were measured. ResultsData collection was completed in all 60 limbs. Sitting or walking without GCS led to no significant volume changes, whereas volume was decreased by the use of GCS (−4.8% [P < .00001] and −4.4% [P < .00001], respectively). Standing up without GCS led to an increase in volume (2.7%; P < .0001), whereas limb volume was decreased (4.6%; P < .0001) by use of GCS. Bioimpedance showed extracellular water reduction only while walking with GCS (from 40.55% ± 1.66% to 40.45% ± 1.71%; P < .017). Mean interface pressure was 19 ± 5 mm Hg (B) and 16 ± 5 mm Hg (B1). The interface pressure variation from B to B1 was not homogeneous among participants (mean percentage variation of −13% ± 25%, ranging from −54% to 16%). A negative linear trend between pressure variation and circumference percentage increase was found; the subanalysis excluding the two outliers showed a strong negative linear correlation (Pearson coefficient r = −0.96). ConclusionsGCS led to a significant limb volume reduction irrespective of limb position and muscle pump function. However, extracellular fluid is mobilized only during muscle contraction while walking with GCS. Interestingly, different lower limb circumference variations influence the interface pressure gradient, indicating the importance of proper fitting of both B and B1 during prescription. These data provide a foundation to future investigations dealing with GCS effect on fluid mobilization and with limb geometry impact on compression performance.

Decreased carbon accumulation feedback driven by climate-induced drying of two southern boreal bogs over recent centuries.

Northern boreal peatlands are important ecosystems in modulating global biogeochemical cycles, yet their biological communities and related carbon dynamics are highly sensitive to changes in climate. Despite this, the strength and recent direction of these feedbacks are still unclear. The response of boreal peatlands to climate warming has received relatively little attention compared with other northern peatland types, despite forming a large northern hemisphere-wide ecosystem. Here, we studied the response of two ombrotrophic boreal peatlands to climate variability over the last c. 200years for which local meteorological data are available. We used remains from plants and testate amoebae to study historical changes in peatland biological communities. These data were supplemented by peat property (bulk density, carbon and nitrogen content), 14 C, 210 Pb and 137 Cs analyses and were used to infer changes in peatland hydrology and carbon dynamics. In total, six peat cores, three per study site, were studied that represent different microhabitats: low hummock (LH), high lawn and low lawn. The data show a consistent drying trend over recent centuries, represented mainly as a change from wet habitat Sphagnum spp. to dry habitat S. fuscum. Summer temperature and precipitation appeared to be important drivers shaping peatland community and surface moisture conditions. Data from the driest microhabitat studied, LH, revealed a clear and strong negative linear correlation (R2 =.5031; p<.001) between carbon accumulation rate and peat surface moisture conditions: under dry conditions, less carbon was accumulated. This suggests that at the dry end of the moisture gradient, availability of water regulates carbon accumulation. It can be further linked to the decreased abundance of mixotrophic testate amoebae under drier conditions (R2 =.4207; p<.001). Our study implies that if effective precipitation decreases in the future, the carbon uptake capacity of boreal bogs may be threatened.

P1820New parameters for the evaluation of mechanic and elastic properties of the aortic root in Marfan Syndrome

Abstract Background Elastic properties of the thoracic aorta in patients with Marfan Syndrome (MS) have already been evaluated with classic echocardiographic parameters. In the latest years the use of Speckle-Tracking (STE) ecocardiography has been widely extended. Our aim is to describe and provide new parameters of aortic deformation measured by STE in patients with MS. Methods 95 unoperated adult patients with MS and 32 healthy controls were prospectively enrolled. We measured classic parameters of the aortic root using 2D echocardiography. We calculated the posterior aortic wall systolic excursion at the sinuses of Valsalva and ascending aorta using M Mode in TDI colour; with ST 2D ecocardiography we measured the aortic strain at the sinuses of Valsalva (SV) and the anterior and posterior aortic wall displacement at the SV. Aortic distensibility was calculated using the formula: 1000 * (Ds − Dd)/Dd * 1/(Ps − Pd) in mmHg–1 (Ds: systolic and Dd: diastolic diameters, Ps systolic and Pd diastolic blood pressure). Aortic stiffness index was calculated as Ln((Ps/Pd)/(Ds-Dd)/Dd)). Results As shown in the table bellow, patients with MS had lower aortic strain, aortic anterior and posterior wall displacement and impaired aortic distensibility and stiffness index compared to healthy controls. We found a strong negative linear correlation between aortic root diameter at the SV and aortic root strain (r=−0.56, figure 1). Results of statistical analysis MS (n=95) Controls (n=32) p Age (years) 32.84±12.35 32.41±7.98 0.85 Aortic root diameter at the sinuses of Valsalva (mm) 38.82±5.35 30.92±3.65 &lt;0.001 Aortic root strain (%) 4.66±2.45 9.19±2.49 &lt;0.001 Anterior aortic wall displacement STE (mm) 10.39±3.64 13.10±2.26 &lt;0.001 Posterior aortic wall displacement STE (mm) 9.02±2.87 11.04±1.82 &lt;0.001 Aortic distensibility 0.98±0.46 1.37±0.72 0.01 Aortic stiffness index 3.74±0.43 3.47±0.51 0.01 MS = Marfan Syndrome; STE = Speckle Tracking Ecocardiography. Figure 1. Dispersion plot Conclusions Our results suggest that aortic deformation and displacement obtained by STE echocardiography is impaired in MS, showing a reduced distensibility and an increased stiffness of the aortic wall, with a strong negative correlation between aortic root dilation and aortic strain. All these parameters may be useful as additional tools for the diagnosis and follow-up of Marfan patients, and could be useful to to improve the echocardiographic evaluation of the aortic root.

Effects of 130 Years of Selected Cropping Management Systems on Soil Health Properties for Sanborn Field

Core Ideas Soil health characterization was useful for discriminating among long‐term cropping systems. Positive associations were found among most soil health properties. Most soil health properties evaluated had negative correlations with bulk density. Incorporation of crop rotations into cropping systems has been suggested as an effective practice to improve soil health for sustainable agriculture. This study was conducted on selected cropping systems with little fertilizer input to evaluate long‐term cropping system effects on soil health properties in Sanborn Field. Soil samples were collected on two dates during 2 yr from each plot. Soil physical, chemical, and biological characteristics were analyzed in the laboratory for these samples to assess soil health using a cumulative normal distribution method. Soil samples collected from Tucker Prairie were used as a proxy for the original state of Sanborn Field soils to compare with soil from the selected cropping systems. The results from the characterization indicated that continuous timothy (Phleum pretense L.) and warm‐season grass treatments were classified with very high soil health scores, followed by middle scores for rotations and continuous wheat (Triticum aestivum L.) and by the lowest score for continuous corn (Zea mays L.). In addition, results showed strong positive linear associations between the following properties: soil organic carbon, total nitrogen, potentially mineralizable nitrogen, active carbon, microbial biomass, and water‐stable aggregates (r = 0.60 to 0.96). In contrast, these properties had strong negative linear correlations with bulk density (r = −0.59 to −0.71). An integrated soil health index requires a combination of soil physical, chemical, and biological properties to adequately assess the soil health status of selected cropping systems and to make potential recommendations for future sustainable management.

Aptamer-based SERS biosensor for whole cell analytical detection of E. coli O157:H7

Infectious outbreaks caused by foodborne pathogens such as E. coli O157:H7 are still imposing a heavy burden for global food safety, causing acute illnesses and significant industrial impact worldwide. Despite the growth of biosensors as a research field, continuous innovation on detection strategies, novel materials and enhanced limits of detection, most of the platforms developed at the laboratory scale never will get to meet the market.The use of aptamers as capture biomolecules has been proposed as a promising alternative to overcome the harsh environmental conditions of industrial manufacturing processes, and to enhance the performance under real, complex, conditions. In this work, we present the feasibility of using aptameric DNA sequences, covalently conjugated to 4-aminothiophenol-gold nanoparticle complexes for the sensitive and highly specific detection of E. coli O157:H7 via surface enhanced Raman spectroscopy (SERS) analysis. Low concentrations of E. coli O157:H7 were detected and quantified within 20 min in both pure culture (∼101 CFU mL−1) and ground beef samples (∼102 CFU mL−1). The SERS intensity response showed a strong negative linear correlation (r2 = 0.995) with increasing concentrations of E. coli O157:H7 (ranging from 102 to 106 CFU mL−1). High specificity was achieved at genus (L. monocytogenes, S. aureus S. typhimurium) species (E. coli B1201) and serotype (E. coli O55:H7) level, demonstrating with 95% of confidence that the interferent microorganisms tested generated a Raman signal response not significantly different from the background (p = 0.786).This work evaluates the incorporation of aptameric DNA sequences as bio capture molecules exclusively. The successful performance presented using non-modified citrate reduced GNPs, is promising for potential low-cost, high-throughput applications. The findings might be applied simultaneously to the detection of a wide variety of foodborne pathogens in a multiplexed fashion employing unique Raman probes and strain-specific aptamer sequences.

Temperature-dependence of the bending elastic constant of DNA and extension of the two-state model. Tests and new insights

Review and analyses of the experimental data indicate that in nearly all cases bending elastic constants of the effective springs between bp of DNA actually undergo a net increase with increasing T from 278 to 315 K. The exceptions to this rule are bending elastic constants obtained from equilibrium topoisomer distributions of a 2686 bp pUC19 DNA by assuming a fixed T-independent value of the torsion elastic constant. When the same data are analyzed using measured T-dependent values of the torsion elastic constant, which decline with increasing T, a modest increase in bending elastic constant with increasing T is obtained. After revising the torsion elastic constants of the previously formulated two-state cooperative transition model to account for additional data, that model is fitted to the bending elastic constants reckoned from the aforementioned topoisomer distributions to determine the best-fit values for each state. The rather good fit implies a strong negative linear correlation between the inverse bending and inverse torsion elastic constants as T is varied. Predictions of the resulting two-state model, wherein each state has fixed bending and torsion elastic constants, agree surprisingly well with single-molecule relative extension and torque data. The same model also yields good agreement with numerous other experimental data. With increasing T the equilibrium is shifted from the (longer, torsionally stiffer, flexurally softer) b-state toward the (shorter, torsionally softer, flexurally stiffer) a-state. This transition is suggested to be the origin of the so-called broad pre-melting transition exhibited by many, but not all, DNAs.

Impact of fruit-tree shade intensity on the growth, yield, and quality of intercropped wheat.

Agroforestry is a common traditional practice in China-especially in the southern Xinjiang of Northwest China. However, the productivity of many agroforestry systems has been lower than expected in recent years, highlighting the need for an actionably deep mechanistic understanding of the competition between crops and trees. Here, three different fruit tree/wheat (jujube/wheat, apricot /wheat, and walnut /wheat) intercropping agroforestry systems were chosen to investigate influence of different fruit tree shade intensity on the growth, yield and quality of intercropping wheat. Compared to the monoculture wheat system, the mean daily shade intensity of the jujube-, apricot-, and walnut-based intercropping systems were, respectively, 23.2%, 57.5%, and 80.7% shade. The photosynthetic rate of wheat in the jujube-, apricot-, and walnut-based intercropping systems decreased by, respectively, 11.3%, 31.9%, and 36.2% compared to monoculture wheat, and the mean number of fertile florets per spike decreased by 26.4%, 37.4%, and 49.5%. Moreover, the apricot- and walnut-based intercropping systems deleteriously affected grain yield (constituent components spike number, grains per spike, and thousand grain weight) and decreased the total N, P, and K content of intercropping wheat. Tree shading intensity strongly enhanced the grain protein content, wet gluten content, dough development time, and dough stability time of wheat, but significantly decreased the softening degree. Strong negative linear correlations were observed between tree shade intensity and the number of fertile florets, grain yield related traits (including spike number, grains per spike, and thousand grain weight), nutrient content (N, P and K), and softening degree of wheat. In contrast, Daily shade intensity was positively linearly correlated with grain protein content, wet gluten content, dough development time, and dough stability time. We conclude that jujube-based intercropping systems can be practical in the region, as they do not decrease the yield and quality of intercropping wheat.